加入收藏  设为首页
 
Home | 中文  
   Home   |   About Journal   |   Editorial Board   |   Instruction   |   Rewarded   |   Indexed-in   |   Impect Factor   |   Subscriptions   |   Contacts Us
News

ScholarOne Manuscripts Log In

User ID:

Password:

Forgot your password?

Enter your e-mail address to receive an
e-mail with your account information.

  Journal Online
    Current Issue
    Advanced Search
    Archive
    Read Articles
    Download Articles
    Email Alert
    
Links  
22 CAST
22 CNCOS
22 CNKI
22 WanfangDATA
22 CHEMSOC
22 sinospectroscopy
22 CPS
Quick Search  
  Adv Search
2016 Vol. 36, No. 05
Published: 2016-05-01

 
       光谱学与光谱分析
1277 Progress of Detection Technology of Ultra-Broadband THz Time-Domain Spectroscopy
DONG Jia-meng1, 2, PENG Xiao-yu2*, MA Xiao-hui1*, LIU Yi1, 2, WEI Dong-shan2, CUI Hong-liang2, DU Chun-lei2
DOI: 10.3964/j.issn.1000-0593(2016)05-1277-07
Terahertz Time-Domain Spectroscopy (THz-TDS) is one of the effective coherent detection techniques. It has been widely applied in materials, chemistry, biology, security and other fields due to its capabilities such as high signal-to-noise ratio (SNR), broadband detection, working at room temperature, time resolved measurement and others. Limited by the spectrum bandwidth of THz radiation and detection techniques, the measuring range of the traditional THz-TDS system is generally less than several THz, thus the spectral information of high frequencies cannot be obtained. In order to expand its application, there is an urgent need for the development of ultra-broadband (≥10 THz) THz-TDS detection techniques. This paper reviews the development and applications of main detection techniques in ultra-broadband THz-TDS. The advantages and disadvantages of these techniques are also analyzed.
2016 Vol. 36 (05): 1277-1283 [Abstract] ( 349 ) PDF (2970 KB)  ( 384 )
1284 Atmospheric Correction for HJ-1 CCD Data Coupling with Aerosol Models of Beijing-Tianjin-Hebei Region
XIE Dong-hai1, 3, CHEN Tian-hai2*, WU Yu2, YU Jie1, 3, GUO Hong2, ZHONG Ruo-fei1, 3
DOI: 10.3964/j.issn.1000-0593(2016)05-1284-07
Current atmospheric correction of HJ-1 CCD does not take the aerosol models of Chinese specific regions into consideration. This paper proposes a method of atmospheric correction coupling local aerosol models. Choosing Beijing-Tianjin-Hebei region as the study area, aerosol model parameters of the method on the foundation of AERONET inversion are analyzed and four types of aerosol model parameters of Beijing-Tianjin- Hebei regions are clustered to build the lookup table for the inversion of aerosol optical thickness. Lack of SWIR (2.12 μm) in the bands of HJ-1 CCD , the blue(0.43~0.52 μm) and red(0.63~0.69 μm) cannot be calculated like the MODIS. So the ratio of blue and red is used as the basis of error equation for aerosol optical depth retrieval, with no need of ground target reflectance. HJ-1 CCD data after atmospheric correction are compared with MODIS surface product data (MOD09) and ASD measurements. The results show that the reflectance obtained by the atmospheric correction is close to the ASD measurement results, and there is a strong correlation with MOD09, the average correlation coefficient in the red band reached more than 0.8, the one of blue band affected by molecule mostly is up to 0.75.
2016 Vol. 36 (05): 1284-1290 [Abstract] ( 320 ) PDF (6687 KB)  ( 183 )
1291 A Methane Gas Sensor Based on Mid-Infrared Quantum Cascaded Laser and Multipass Gas Cell
LI Chun-guang1, DANG Jing-min1, LI Jian1, 3, FU Li1, CHEN Chen2*, WANG Yi-ding1*
DOI: 10.3964/j.issn.1000-0593(2016)05-1291-05
According to the principle of mid-infrared absorption spectrum, the fundamental absorption characteristics at the wavelength of 7.5 μm of methane (CH4) molecule was used to design a mid-infrared quantum cascaded laser (QCL) and multi-pass gas cell (MPC)-based methane gas sensor. This sensor uses a thermoelectrically cooled, pulse mode QCL whose central wavelength is 7.5 μm. The QCL wavelength was scanned over CH4 absorption line (1 332.8 cm-1)through adjusting the injection current under the condition of room temperature. Meanwhile, a compact MPC (40 cm long and 800 mL sampling volume) was utilized to achieve an effective optical path length of 16 meters. Additionally, a reference gas cell was occupied and joined a spatial filtering optical structure to meet the requirement of MPC in incidence beam, effectively improved the beam quality, reduced the noise which is caused by the fluctuation of QCL and improved the detection sensitivity of this instrument under the guidance of differential optical absorption spectroscopy method. It indicated that the stability of this instrument is good by means of multiple measurements to the methane gas with different concentration, a detection limit of 1 μmol·mol-1 will be obtained when the signal-to-noise ratio equals 1.
2016 Vol. 36 (05): 1291-1295 [Abstract] ( 342 ) PDF (2685 KB)  ( 242 )
1296 A New Method for Measurement of Laser-Induced Damage Threshold
GE Jin-man1,2, SU Jun-hong1,2*, CHEN Lei1, Lü Ning2
DOI: 10.3964/j.issn.1000-0593(2016)05-1296-04
With the development of the laser towards high-power and high energy, laser-induced damage threshold of optics becomes one of the important parameters to evaluate the laser damage resistance of optics. Therefore, accurately measuring of the laser-induced damage threshold optics become the focal point studied. And the key to accurately measuring of the laser-induced damage threshold is whether the laser-induced damage can be accurately identified when it occurs. In order to solve low accuracy, long testing time, narrow scope of applications and complex operation of the common damage identification methods, a new testing method to diagnose the laser-induced damage of optics, called plasma diagnosis, is proposed in this paper. Based on this new method, the testing platform was set up, and the spectrum obtained by fiber spectrometer was analyzed under laser radiation by different laser energies. Take whether the spectral lines of the feature element contained in the measured optics occur as standard. The laser-induced damage threshold of K9 glass has been tested, and the test result was compared to that measured by the plasma flash method and the microscope method. The results show that, the plasma diagnosis method proposed in this paper has high-accurate judgment, high- testing speed, simple testing equipment, and easy to realization, which can greatly improve the testing efficiency of the laser-induced damage threshold of optics.
2016 Vol. 36 (05): 1296-1299 [Abstract] ( 343 ) PDF (1521 KB)  ( 550 )
1300 Research on the Distribution of Broad-Band Correlated Photon Spectra and the Measurement of Time-Correlation
GAO Dong-yang1, 2, LI Jian-jun1, XIAO Mao-peng1, ZHENG Xiao-bing1, 2*
DOI: 10.3964/j.issn.1000-0593(2016)05-1300-08
The correlated photon technique makes it possible to achieve a radiation calibration processing without chain transferring. The study of the spectral radiation character and time correlation of the photon is of great significance for broad-band radiometric calibration. To absolutely calibrate quantum efficiency of photoelectric detector, it is necessary to extend calibration band from single band to more bands. According to the phase-matching condition of the spontaneous parametric down-conversion, non-collinear angle formula of correlated photon in the crystal is derived. The distribution of the photon spectrum is simulated. Meanwhile, the phase-matching angle of the crystal is optimized. The photon generated by the spontaneous parameters down-conversion has a broad spectral distribution and the correlated photon wavelength is corresponding to its emission angle. Based on the result of the simulation, the experimental measurement system of the spectral distribution and time-correlation of the correlated photon is established. The spectral distribution, the time-correlation and the polarization properties of the four pair photon were measured by using this system. The experimental results show that, (1) the spectral distribution of the measurements is 633~808 nm, where the maximum spectral distribution measurement bias is 1.51 mm. The experiment result is highly consistent with theoretical ones; (2) the correlation time of four pairs correlated photon is measured, during which “three coincidence-peaks” is observed and the minimum correlation time was 0.32 ns; (3) single photon count rate along with coincidence count rate of correlated photon vary with the polarization direction of the pump as sine function. The experimental result is shown that the correlated photon pairs are ranging from the visible to near infrared band distribution, and that the spectrum has time-correlation and polarization characteristic. The research result is firstly reported at home and abroad, and the results are promising for the application of the photoelectric detector in the multi-band radiometric calibration.
2016 Vol. 36 (05): 1300-1307 [Abstract] ( 276 ) PDF (3471 KB)  ( 202 )
1308 Multi-Pass Absorption Spectroscopy for CO Detection Using a Quantum Cascaded Laser
LI Chun-guang1, DANG Jing-min1, CHEN Chen2*, WANG Yi-ding1*
DOI: 10.3964/j.issn.1000-0593(2016)05-1308-05
According to the fundamental absorption properties of Carbon Monoxide(CO) near 4.7 μm, a novel CO sensor was designed using a Quantum Cascaded Laser (QCL) whose central wavelength is 4.75 μm and Multi-pass Gas Cell (MGC). This sensor uses a QCL with the thermoelectrically cooled function and can work under pulse mode and room temperature, the exiting optical wavelength was located in a strong absorption line (2 103 cm-1)which is in the base band of CO through adjusting the injection current and temperature. Meanwhile, a novel MGC (40 cm long and 800 mL sampling volume) with 16 meters effective optical path length and mercury cadmium telluride mid-infrared detectors was used, thus effectively improved the sensitivity of this system. Additionally, a reference gas cell and a spatial filtering optical structure were occupied, resulting in effective improvement of the beam quality and reduction of the noise caused by the instability of QCL, the sensitivity of this system was improved furtherly. It indicated that the system works stably by means of multiple measurements to the carbon monoxide gas with different concentration, a detection limit of 5 μmol·mol-1 can be obtained when the signal-to-noise ratio equals 1.
2016 Vol. 36 (05): 1308-1312 [Abstract] ( 343 ) PDF (2515 KB)  ( 179 )
1313 A Study of Lasing Spectrum of Dye-Doped Chiral Nematic Liquid Crystal Cell under Electric Field
WU Ri-na1, WU Xiao-jiao1, WU Jie1, PENG Zeng-hui2, YAO Li-shuang2 , DAI Qin1*
DOI: 10.3964/j.issn.1000-0593(2016)05-1313-04
The lasing spectrum of dye-doped chiral nematic liquid crystal under electric filed was investigated. Two kinds of electrodes were designed to apply transverse electric field to positive liquid crystal cell and longitudinal electric field to negative liquid crystal cell. A 532 nm Nd∶YAG pulsed solid-state laser was used to pump the cell. When transverse electric field is applied to positive liquid crystal device, multi-wavelength laser output is obtained in the range of 630~660 nm. When longitudinal electric field is applied to negative liquid crystal cell, 18.5 nm tunable output lasing is obtained. The output characteristic of cell was analyzed from the texture of device and the photonic band gap. In the positive liquid crystal cell, the competition of electric moment with twisting moment causes the flow of LC molecule, and the flow of LC molecule leads to a floating photonic band gap. For this reason, not only at the edge of photonic band gap but in the photonic band gap can produce lasing. For negative liquid crystal cell, the pitch shrinks with the increase of electric field. The photonic band gap shows blue-shift with the decrease of pitch. and Lasing wavelength is blue shifted from 681.0 to 662.5 nm and the lasing at the edge of photonic band gap. Negative liquid crystal cell has better stability under electric field effect.
2016 Vol. 36 (05): 1313-1316 [Abstract] ( 299 ) PDF (2225 KB)  ( 159 )
1317 Quantum State-Resolved Energy Redistribution of CO2 from Collisions with Highly Vibrationally Excited NaH
Abai Alghazi1, 2, LIU Jing1, DAI Kang1, SHEN Yi-fan1*
DOI: 10.3964/j.issn.1000-0593(2016)05-1317-06
Degenerate stimulated hyper-Raman pumping is used to excite high vibrational states of NaH. The full state-resolved distribution of scattered CO2(0000, J) molecules from collisions with excited NaH(ν″=14, J=21) was reported. The nascent number densities of NaH were determined from absorption measurements at times t=1 μs as the laser to prepare NaH(ν″, J″). Absorption signals were converted to NaH(ν″, J″) population using absorption coefficients and the transient Doppler-broadened linewidths. The nascent CO2(0000, J) population were obtained from transient overtone laser induced fluorescence line intensity measured at short times relative to the time between collisions. The scattered CO2(0000, J=2~80) molecules had a biexponential rotational distribution. Fitting the data with a two-component exponential model yielded CO2 product distributions with Trot=(650±80) and (1 531±150) K. The cooler distribution accounted for 79% of the scattered population and resulted from elastic or weakly inelastic collisions that induced very little rotational excitation in CO2. The hotter distribution involved large changes in CO2 rotational energy and accounted for 21% of collision. Nascent translational energy profiles for scattered CO2 (0000, J=60~80) were measured using high resolution transient overtone fluorescence. The relative translational energy of the scattered molecules increased as a function of final CO2 rotational state with 〈ΔErel〉=582 cm-1 for J=60, and 2 973 cm-1 for J=80. Energy transfer rates were determined for the full J-state distribution by monitoring the change of the nascent population. The total rate constant for appearance of scattered CO2(0000) was kapp=(7.2±1.8)×10-10 cm3·mol-1·s-1. The depletion for the low-J CO2 states was involved in the collisional energy transfer of the initial distribution. For J=2~38, the average rate constant for depletion of scattered CO2(0000) is 〈kdep〉=(6.9±1.7)×10-10 cm3· mol-1·s-1.
2016 Vol. 36 (05): 1317-1322 [Abstract] ( 301 ) PDF (2285 KB)  ( 164 )
1323 Characterization of Plasma Induced by Laser Effect on Coal Sample
ZHANG Gui-yin1, JI Hui1, LI Song-tao1, ZHENG Hai-ming2
DOI: 10.3964/j.issn.1000-0593(2016)05-1323-05
With the output of an OPG/OPA pumped by the third harmonic output 355 nm of a pulsed Nd·YAG laser as radiation source, the emission spectrum of laser induced coal sample plasma is created. The emission spectral line shows the character of Lorenz profile. So Stark broadening is the main widening way of this plasma system. The spatial distribution of the plasma temperature and electron density is measured from the intensity and Stark broadening of the spectral lines. It is found that in the direction from vertical to plasma luminous flame, both plasma temperature and electron density are symmetrically relative to the center. While in the direction of parallel to plasma luminous flame, they are asymmetrically relative to the center. Plasma temperature and electron density is maximized in the centre of the flame, and the emission intensity of the plasma in the centre is also strong. So we ought to collect the emission spectrum in the plasma centre when using the technique of spectroscopy for the diagnosis of plasma characteristics. It is also found that there is a dip in the centre of some spectral lines. This indicates that there exists strong self-absorption in the plasma. The appearance of self-absorption varies with laser wavelength. It is most obvious when the wavelength is near to the center of the profile, because the transition probability is the largest at the center of the profile. Both emission intensity and self-absorption increase with laser energy. These experimental results can be interpreted as the increase of the particle density with laser energy. Thus we ought to select spectral lines with no self-absorption when measuring the parameters of the plasma with the technique of laser spectroscopy. This can ensure higher detection accuracy.
2016 Vol. 36 (05): 1323-1327 [Abstract] ( 282 ) PDF (1576 KB)  ( 180 )
1328 The Optics and Magnetic Properties of Cr Doped ZnO Thin Films
CHEN Xiang1, YANG Wen-yu1, ZHANG Hui-qin1, ZOU Ming-zhong1, ZHUANG Bin1, LIN Ying-bin1,2, HUANG Zhi-gao1,2*
DOI: 10.3964/j.issn.1000-0593(2016)05-1328-06
The precursor solution is sent to the ultrasonic nozzle directly through a needle tube to prepare Zn1-xCrxO (x=0, 0.01, 0.03 and 0.05)films on quartz substratesby ultrasonic spray method. The structures, optical and magnetic properties of the films were measured by X-ray diffracmeter(XRD), scanning electron microscope(SEM), fluorescence spectrometer, ultraviolet-visible light detector, vibrating sample magnetometer (VSM) and so on. The experimental results indicate that, the undopedZnO thin films exhibit the hexagonal wurtzite crystalline structure with a preferential orientation of (002); the Cr doping restrains the preferred orientation of C axis; the average grain sizes of the samples increase withCr doping, and thesize attains the maximum(31.4 nm) when x=3%. The SEMimages show that the Zn1-xCrxO (x=0, 0.01, 0.03 and 0.05) films are grain-like particles. And it exhibits a long strip shape when x=5%. Moreover, the doping of Cr makes the photoluminescence (PL) spectra of Zn1-xCrxO films change evidently. The undoped sample shows an ultraviolet emission peak at 378 nm as well as a defect related green peak at around 550 nm. However, for the doping samples, there is only a wide range of emission peak from 350 to 550 nm. By gaussian fitting,it is found that VZn, Zni and V-Zn defects exist in the Cr doping films, and VZn is largest when x=3%. The band gap increases with the doping of Cr, and reaches the maximum when x=3%. The doping of Cr hasthe band gap of the samples increase, and the band gapreachs themaximum(3.37 eV) when x=3%. Magnetic measured results show that threedoping samples Zn1-xCrxO(x=1%, 3% and 5%) are ferromagnetic at room temperature, and the magnetization of Zn1-xCrxO (x=3%) is the largest, which is corresponding to the most VZn defect. The experimental results also prove the the oretical prediction that the substitutive Cr in the oxidation state of +3 and the neutral Zn vacancy in the ZnO∶Cr sample are the most favorable defect complex to maintain a high stability of ferromagnetic order.
2016 Vol. 36 (05): 1328-1333 [Abstract] ( 343 ) PDF (2918 KB)  ( 174 )
1334 Calibration Transfer of Near Infrared Spectrometric Models for Crude Protein of Protein Feed Materials
DING Ke, ZHANG Yue-jing, SHEN Guang-hui, YU Xian-long, YANG Zeng-ling, LIU Xian*
DOI: 10.3964/j.issn.1000-0593(2016)05-1334-06
The near infrared spectrometric quantitative model of protein feed and its sharing in different instruments can greatly improve the utilization efficiency of the model and meet the needs of rapid development of feed industry. Considering the issue of applicability of near infrared spectrometric models for crude protein of protein feed materials, calibration transfer was explored among three types of instruments using spectral subtraction correction, direct standardization and piecewise directs standardization methods for the first time. Four kinds of protein feed raw materials were involved in the present study, corn protein powder, rapeseed meal, fish meal and distillers dried grains with soluble. The experimental instruments included MATRIX-I Fourier transform near infrared instrument (master instrument), Spectrum 400 Fourier transform near infrared instrument (slave 1 instrument), and SupNIR-2750 grating near infrared instrument (slave 2 instrument). Results showed that the spectral data difference for all the samples between the master and slave 2 instrument was relatively small, and the difference between the master and slave 1 instrument, and slave 1 and slave 2 instrument were relatively large. All the root mean square error of prediction and bias values after calibration transfer were lower than the values before calibration transfer, except that no improvement was found for the prediction of corn protein powder of slave 2 instrument corrected by piecewise direct standardization method. The relative prediction deviation (RPD) of corn protein powder, rapeseed meal and distillers dried grains with soluble transferred by all three methods were higher than 3, which indicated good predictions, while the RPD of fish meal were all higher than 2.5, which indicated relative good predictions. All three techniques used in the study were effective in the correction of the difference between different instruments for protein feed materials. This study is of important practical significance for the application of near infrared spectrometric models for crude protein of protein feed materials.
2016 Vol. 36 (05): 1334-1339 [Abstract] ( 292 ) PDF (2537 KB)  ( 235 )
1340 Optimizing Savitzky-Golay Parameters and Its Smoothing Pretreatment for FTIR Gas Spectra
ZHAO An-xin1, 2, TANG Xiao-jun2, ZHANG Zhong-hua2, 3, LIU Jun-hua2
DOI: 10.3964/j.issn.1000-0593(2016)05-1340-05
In the smoothing pretreatment for the quantitative analysis of hydrocarbon mixed gases by Fourier transform infrared analysis (FTIR), the Savitzky- Golay filter is usually used as one of the smoothing preprocessing methods in the Fourier transform infrared spectrum data smoothing pretreatment. However, the parameters of the Savitzky-Golay filter such as the polynomial order and frame size are not easy to decide. There is no one unified choice basis. Users usually adopt multiple sets in the special data set to try, and then select a set of relatively optimal data as the optimizing parameters of the Savitzky-Golay filter. The optimal selection method of the Savitzky-Golay filter parameters was explored, and the concrete calculation equations were deduced according to the relation among the normalized cut-off frequency, the normalized beginning frequency of the stopband, the normalized first side lobe peak frequency of the stopband, the normalized first side lobe peak amplitude with the polynomial order and frame size of the Savitzky-Golay filter parameters. Then when the polynomial order and frame size are set as 8 and 11 respectively according the above conclusion and the characteristics of the actual spectral data, the Savitzky - Golay filter smoothing effect is optimum. Through the acquisition the concentration of 0.1%, 0.2%, 0.5%, 1%, 2%, 5% for the actual CH4 spectra, the relative maximum and minimum error of the raw spectra converted absorbance were 17.230 5% and 0.243 0% respectively, and the relative maximum and minimum error of the smooth spectra converted absorbance were 0.088 0% and 0.088 0% respectively in the second absorption peak. The relative error of converted absorbance was basically stable through the Savitzky-Golay filter after the spectral data preprocessing and it was relatively low, so, it laid a foundation for the late spectral data accurate qualitative and quantitative analysis.
2016 Vol. 36 (05): 1340-1344 [Abstract] ( 456 ) PDF (3447 KB)  ( 236 )
1345 Application of Wavelet Transform and Successive Projections Algorithm in the Non-Destructive Measurement of Total Acid Content of Pitaya
LUO Xia1, 2, 3, HONG Tian-sheng2, 3, 4*, LUO Kuo2, 3, 4, DAI Fen1, 2, 3, WU Wei- bin2, 3, 4, MEI Hui-lan2, 3, 4, LIN Lin4
DOI: 10.3964/j.issn.1000-0593(2016)05-1345-07
The objective of present study was to find out an accurate, rapid and nondestructive method to detect total acid content (TA) of pitaya with visible/near-infrared spectrometry, wavelet transform (WT) and successive projections algorithm (SPA), which will provide scientific basis for non- destructive measurement of pitaya. Maya2000 fiber-optic spectrumeter was used to collect spectral data of pitaya on the wavelength in the range of 380~1 099 nm; and then with the methods of WT denosing pretreatment, SPA and partial least squares regression (PLSR) quantitative forecasting model of TA of pitaya was established. The result showed that the precision of WT-SPA-PLSR model, which combine the WT with SPA, was better than that of PLSR model based on the whole wave variables. The relation coefficient of the PLSR model (Rp) that predicted TA based on the original spectrum of all samples as the input variables was 0.851 394 and RMSEP was 0.086 848. The original spectrum variable of the all samples were processed by using wavelet function dbN(N=2, 3, …, 10) for wavelet decomposition and de-noising. The optimal results of noise reduction were decomposed in level 2 using wavelet function db4 (db4-2). The Rp of WT-PLSR model was 0.915 635 and RMSEP was 0.066 752. The prediction of model using wavelet transform de-noising was improved significantly. After the original spectrum processed by db10-3 and SPA, 12 preferred variables were selected from 570 spectrum variables, such as 530, 545, 604, 626, 648, 676, 685, 695, 730, 897, 972, 1 016 nm spectrum variables. The WT-SPA-PLSR model based on these 12 variables as input variables was established. Rp of the WT-SPA-PLSR prediction model was 0.882 83 and RMSEP was 0.077 39. SPA algorithm was suitable for the selection of spectrum variables which could effectively obtain the spectrum variables which were strong correlation with TA and increase the accuracy and stability of the prediction model. The results indicated that the nondestructive detection for TA of pitaya based on the diffuse reflectance visible/near-infrared spectrometry, WT and SPA was feasible.
2016 Vol. 36 (05): 1345-1351 [Abstract] ( 351 ) PDF (2061 KB)  ( 205 )
1352 Study on the Nondestructive Detection Methods for Dynamica Change of Lipid Content in Chlorella sp.
WEI Xuan1, 2,JIANG Lu-lu3,ZHAO Yan-ru2,SHAO Yong-ni2,QIU Zheng- jun2,HE Yong2*
DOI: 10.3964/j.issn.1000-0593(2016)05-1352-06
Microalgae based biodiesel production requires a large amount of lipid accumulation in the cells, and the accumulation is greatly influenced by the environment. Therefore, it is necessary to find fast and non-destructive methods for lipid change detection. In this paper, Chlorella sp. was adopted as the objective, which was cultured under different light condition consisted of red and blue lights with different proportion. We applied the visible near-infrared spectroscopy (Vis/NIRs) technique to detect the dynamic change of lipid during the microalgae growth processes and utilized hyperspectral imaging technology for visualization of lipid distribution in the suspension. The transmittance and reflectance spectra of microalgae were acquired with Vis/NIRs and hyper-spectroscopy, respectively. In the comparison of the transmittance and reflectance spectra, they showed some different characteristics. Meanwhile it also varied in terms of the number and the area of feature wavelengths obtained by successive projections algorithm (SPA) based on the different spectra. But the established multiple linear regression (MLR) model for lipid content prediction had similar results with rpre of 0.940, RMSEP of 0.003 56 and rpre of 0.932, RMSEP of 0.004 23, respectively. Based on the predictive model, we obtained the spectra and analyzed the lipid dynamic change in microalgae in one life cycle. In the life cycle, the lipid content in Chlorella sp. was relatively stable from the beginning of inoculation to exponential phase, the increase and accumulation of lipid phenomenon occurred in the late exponential phase. Combined with the MLR model and the hypersepctral images, we studied the visualization result of microalgae suspension in the steady phase. The stimulated images showed that the microalgae with higher lipid content appeared gathering. This study compared the difference and the feasibility of the Vis/NIRs and hyperspectral imaging technique in lipid content detection applied in microalgae growing microalgae. The results are meaningful for the fast and non-destructive detection of the growth information of microalgae. It has boththeoretical and practical significance for developing microalgal culture and harvest strategy in practice.
2016 Vol. 36 (05): 1352-1357 [Abstract] ( 311 ) PDF (3093 KB)  ( 173 )
1358 Study on the Discrimination of FTIR Spectroscopy of Gentiana Rigescens with Different Harvest Time
SHEN Yun-xia1, 2, ZHAO Yan-li1, ZHANG Ji1, JIN Hang1, WANG Yuan-zhong1*
DOI: 10.3964/j.issn.1000-0593(2016)05-1358-05
The harvest time of traditional Chinese medicine (TCM) is a very essential part for the production and quality of TCM which is the prerequisite for safe and effective clinical use of TCM. It is of great importance to carry out the research of timely harvest time of TCM. With Fourier transform infrared spectroscopy (FTIR) to study harvest time of Seventy-two Gentiana Rigescens samples. First derivative, second derivative, standard normal variate, multiplicative scatter correction and Savitaky-Golay(15,3) smoothing of all original spectra were pretreated with TQ8.0 software. Samples were divided into calibration set and prediction set at the ratio of 3∶1. Principal component analysis (PCA) and partial least square discriminant analysis (PLS-DA) model were established. The result indicated that after removing noise spectrum, the spectra range was from 1 800 to 600 cm-1, the method SNV combined with SD and SG present the best result of spectra pretreatment. The contribution rates of first three principal components were 92.47% with PCA. Small differences were found for the samples harvested in May, September and October. Same spectrum range was chosen and PLS-DA was applied to establish the model. The R2 and RMSEE were 0.967 8, 0.086 0, respectively, and the prediction accuracy is 100%. The methods of PCA and PLS-DA have good ability to classify and identify different harvest time of Gentiana Rigescens. It provided a basis for the identification of different harvest time of TCM.
2016 Vol. 36 (05): 1358-1362 [Abstract] ( 283 ) PDF (2170 KB)  ( 136 )
1363 Identification of Planting Area and Varieties of Rapeseeds by Infrared Spectroscopy Combing with Stepwise Discriminatory Analysis
LIU Fei1, YANG Chun-yan1, XIE Jian-xin2
DOI: 10.3964/j.issn.1000-0593(2016)05-1363-06
The planting area and varieties of rapeseeds were studied based on Fourier transform infrared spectroscopy (FTIR) combining with stepwise discriminatory analysis. The FTIR of 188 rapeseed skin samples of 17 varieties from 5 planting areas was obtained and processed by OMINC 8.0 software. In order to distinguish their planting area and variety, 5 spectra in the range of 1 800~950 cm-1 for each variety from each producing area were selected as training samples arbitrarily with Fisher linear discriminatory criterion which was used to build model by means of stepwise discriminatory analysis by SPSS20.0 software. All the five discriminatory models based on Wilks’Lambda, Unexplained variance, Mahalanobis distance, Smallest F value and Rao’s v can distinguish variety and planting area well, and the best one for identifying variety was on the base of Wilks’Lambda, which yielded correct rate of 97.9%, and the best one for distinguishing planting area was on the base of Unexplained variance with a correct rate of 98.4%. The results showed that discriminatory analysis based on the infrared spectrum of rapeseed skin is an efficient method for identification of rapeseed variety and planting area.
2016 Vol. 36 (05): 1363-1368 [Abstract] ( 294 ) PDF (1570 KB)  ( 165 )
1369 Study on the Discrimination of Gentiana Rigescens with Different Processing Methods by Using FTIR Spectroscopy
SHEN Yun-xia1, 2, ZHAO Yan-li2, ZHANG Ji2, WANG Yuan-zhong2*, ZHANG Qing-zhi1*
DOI: 10.3964/j.issn.1000-0593(2016)05-1369-05
The Processing of traditional Chinese medicine (TCM) is the key to clinical application of TCM, and processing has functions such as enhancing the efficacy, attenuating the toxicity andmoderating medicine property. In order to the realizing safe, reasonable and effective use of medicine in clinical, research on identification of TCM processed products is of great significance. The Gentiana rigescens samples which processed with five different methods were discriminated by Fourier transform infrared spectroscopy (FTIR). Baseline correction and normalization were used to pretreat all original spectra and the noise was cut off. The spectra range was from 3 400 to 600 cm-1. The effect of multiple scattering correction and standard normal variable on the model were observed and compared. Samples were divided into calibration set and prediction set at the ratio of 3∶1. The principal component analysis (PCA) was applied to reduce data dimensionality and discriminant analysis model was established. The result indicated that the main absorption peaks of samples were 3 378, 2 922, 1 732, 1 610, 1 417, 1 366, 1 316, 1 271, 1 068, 1 048 cm- 1 which 1 738, 1 643, 1 613, 1 420, 1 051 cm-1 as to gentiopicrin; 1 068, 1 048, 935 cm-1 as to carbohydrate. The accumulation contribution rate of first three principal components is 94.05%. Most of the information reflected the original data. There were differences among different samples. The result of discriminant analysis showed that the recognition rate of G. rigescens samples could achieve to 100% based on baseline correction and normalization treatment combined with MSC with the precondition of principal component scores being 10. In conclusion, FTIR is a feasible, rapid and non-destructive method to discriminate G. rigescens samples wtih different processing methods. It also provided reference for discrimination of processed products of medicine materials.
2016 Vol. 36 (05): 1369-1373 [Abstract] ( 289 ) PDF (1335 KB)  ( 164 )
1374 Research on Pyrolysis Process of Kevlar Fibers with Thermogravimetric Analysis coupled and Fourier Transform Infrared Spectroscopy
YANG Ming, ZHU Xiao-ling, LIANG Guo-zheng*
DOI: 10.3964/j.issn.1000-0593(2016)05-1374-04
Modern industrial application and technologies require materials with superior mechanical and thermal properties. Kevlar fibers have been known as fibrous materials with good properties of high strength and high decomposition temperature which have become a hot research field in recent years. The properties of fibrous materials depend on their structures and compositions. Thermal decomposition processing of the materials is of great significance for their structures and thermal properties. As a new technique, thermogravimetric (TG) analysis coupled with Fourier transform infrared spectroscopy(FTIR), are able to analyze materials not only qualitatively but also quantitatively. This method has obvious advantages in researching the thermal decomposition of many materials. However, the thermal decomposition processing of Kevlar fibers is rarely reported in the literature, therefore, we firstly studied the pyrolysis behavior of Kevlar fibers with thermogravimetric analysis coupled with Fourier transform infrared spectroscopy at the temperature of 30~800 ℃. We not only obtained the processing of the Kevlar fibers’ thermal decomposition with great details but also the products of every stage. Experimental results exhibited that the decomposition of Kevlar fibers has experienced three stages: 100~240, 240~420 and 420~800 ℃. The weight loss of Kevlar fibers was quite slow before 500 ℃. The third stage was the main stage of the decomposition, and the amount of residue finally reached to a mass percent of 56.21%. FTIR analysis illustrated that free water released from Kevlar fibers at the first stage, followed by the dehydration and depolymerization which made polymer chains short. Finally the fiber fragments further reacted and produced the gases of small molecular mass, and the main products were water, ammonia, carbon monoxide and carbon dioxide. Generation rate of water was increased; the emission of ammonia was at the same rate; carbon monoxide was only produced at the temperature of 515~630 ℃, then turned into carbon dioxide. The release of carbon dioxide was on rise because of the conversion process of carbon monoxide, and then dropped to a certain value.
2016 Vol. 36 (05): 1374-1377 [Abstract] ( 317 ) PDF (1636 KB)  ( 139 )
1378 Soil Moisture Monitoring Based on Angle Dryness Index
GAO Zhong-ling1,2, WANG Jian-hua1, ZHENG Xiao-po1, SUN Yue-jun1, QIN Qi-ming1,3*
DOI: 10.3964/j.issn.1000-0593(2016)05-1378-04
Soil moisture content (SMC) is one of the most important indicators influencing the exchange of energy and water among vegetation, soil, and the atmosphere. Accurate detection of soil moisture content is beneficial to improving the precision of crop yield evaluating and field management measures. In this paper, a novel method ADI (Angle Dryness Index) based on NIR-RED spectral feature space used for calculating SMC was proposed, which improved the accuracy of calculating SMC with red and near infrared band reflectance. It was found that an intermediate parameter θ in NIR-RED feature space was significantly related to SMC, and independent of vegetation coverage according to the linear decomposition of mixed pixel and the empirical correlation between SMC and red/NIR band reflectance which were achieved by previous researches. Then, ADI was proposed with the feature discovered in the paper. The mathematical expression on SMC is nonlinear, and the newton iterative method is applied to ADI for calculation SMC. Then, the newly proposed method was validated with two kinds of remote sensing imagery data (Thematic Mapper (TM) and moderate resolution imaging spectrometer (MODIS)) and the synchronous observed data in the field. Validation results revealed that the ADI- derived SMC was highly accordant with the in-situ results with high correlation (R2=0.74 with TM and R2=0.64 with MODIS data). We also calculated MPDI (Modified Perpendicular Drought Index) developed by Ghulam, which is also proposed with the red and near infrared reflectance. The result showed that the accuracy of MPDI was lower than that of ADI. The most likely reason was that ADI was insensitive to fv, but the calculation errors of fv would reduce the accuracy of SMC estimation. MODIS had a low spatial resolution, thus there may be more than two end members in a mixed pixel. In this case, the linear decomposition of mixed pixel was not applicable and the errors would finally be enlarged. ADI achieved good results in monitoring SMC in vegetated area because it was less influenced by vegetation coverage than other similar approaches. ADI only requires the satellite image data including the red and near infrared band which are available from most of the optical sensors. Therefore, it is an effective and promising method for monitoring SMC in vegetated area, and would be widely used in agriculture, meteorology, and hydrology.
2016 Vol. 36 (05): 1378-1381 [Abstract] ( 301 ) PDF (1517 KB)  ( 249 )
1382 Experimental Study and DFT Calculation of FTIR, FT-Raman and THz-TDS Spectra of Ⅰ and Ⅲ Polymorphs of Chlorpropamide
FANG Hong-xia, ZHANG Qi, ZHANG Hui-li, HONG Zhi, DU Yong*
DOI: 10.3964/j.issn.1000-0593(2016)05-1382-07
The absorption spectra of Ⅰ and Ⅲ polymorphs of chlorpropamide were measured with terahertz time-domain spectroscopy (THz-TDS) technique, FT-IR and FT-Raman at room temperature. The results showed that there were distinct differences of Ⅰ and Ⅲ polymorphs of chlorpropamide in those spectra. The IR spectra of two polymorphs of chlorpropamide had showed differences both in the frequencies of the vibrational bands and in the relative band intensities. The obvious differences in Raman spectra of polymorphs of chlorpropamide were that the characteristic peaks of Ⅲ- form were more than Ⅰ-form in 100~1 800 cm-1 region. Absorption peaks observing in the terahertz spectra ofⅠ-form were at 0.90, 1.09 and 1.29 THz and Ⅲ-form were at 0.92, 1.11, 1.23 and 1.63 THz. The maximum difference between Ⅰ-form and Ⅲ-form was that the strong peak appeared at 1.63 THz of Ⅲ-form. The characteristic absorption bands of two polymorphs of chlorpropamide were assigned based on the simulation results of DFT calculation. The simulation result is in accordance with the experiment. From simulation results, it is found that the vibration modes of Ⅰ-form and Ⅲ-form were similar in IR and Raman spectra, but there were more differences in terahertz spectra. The study can provide experimental and theoretical references for the application of FT-IR , FT-Raman and THz-TDS spectra techniques to detect pharmaceutical polymorphs.
2016 Vol. 36 (05): 1382-1388 [Abstract] ( 427 ) PDF (2254 KB)  ( 220 )
1389 Effects of Enhanced Ultraviolet B Irradiation on Photosynthetic and Antioxidant System of Sorghum Seedlings
SHI Xin-xin1, 2, 3, LI Zuo-tong1, 2*, YANG Ke-jun1, 2, ZHAO Chang-jiang1, 2, 3*, YANG Rong -bin4, YU Gao-bo1, HUANG Shou-guang1, XU Jing-yu1, 2, HE Lin1, 2, ZHAO Ying1, XU Yan-mei1, MA Li-feng1, FAN Bo-wen1
DOI: 10.3964/j.issn.1000-0593(2016)05-1389-07
The UV-B radiation on the surface of our planet has been enhanced due to gradual thinning of ozone layer. The change of solar spectrum UV-B radiation will cause damage to all kinds of terrestrial plants at certain degree. In this paper, taking breeding sorghum (Sorghum bicolor (L.Moench))variety Longza No.5 as sample, 40 μW·cm-2 UV-B radiation treatment was conducted on sorghum seedlings at two-leaf and one-heart stage and different time courses; then after a 2 d recovering, photosynthetic parameters were measured with a photosynthetic apparatus; the activities of antioxidant enzymes were detected as well. Our results revealed that, as the dosages of UV-B increasing, leaf browning injury was aggravated, plants dwarfing and significantly were reduced fresh weight and dry weight were observed; anthocyanin content was significantly increased; chlorophyll and carotenoid content significantly were reduced and net photosynthetic rate and chlorophyll fluorescence parameters were decreased. Meanwhile, with the increase in UV-B dosages, stomatal conductance, intercellular CO2 concentration and transpiration rate showed “down - up - down” trend; the activities of SOD and GR presented “down - up” changes; activities of POD and CAT demonstrated “down - up - down”, and APX, GPX showed an “up - down - up” pattern. It is worth to note that, under the four-dose treatment, a sharp decline in net photosynthesis in sorghum seedlings was observed at 6 h UV-B treatment (equals to 2.4 J·m-2), and an obvious turning point was also found for other photosynthetic parameters and activities of antioxidant enzymes at the same time point. In summary, the results indicated that the enhanced UV-B radiation directly accounted for the damages in photosynthesis system including photosynthetic pigment content, net photosynthetic rate and chlorophyll fluorescence parameters of sorghum; the antioxidant system showed different responses to UV-B radiation below or above 6 h treatment: ASA-GSH cycle was more sensitive to low-dose UV-B radiation, while high-dose UV-B radiation not only undermined the photosynthesis system, but also triggered plant enzymatic and non-enzymatic antioxidant systems, resulting in leaf browning and necrosis,biomass accumulation reduction, plant dwarfing and even death.
2016 Vol. 36 (05): 1389-1395 [Abstract] ( 380 ) PDF (1735 KB)  ( 294 )
1396 Rapid Detection of Ammonia Nitrogen in Water with Dual-Wavelength Spectroscopy
WU Hui-ling1, HU Zhan-bo1*, CHAI Xin-sheng2, WANG Cui1, YANG Ou-meng1
DOI: 10.3964/j.issn.1000-0593(2016)05-1396-04
Ammonia nitrogen is an important indicator to measure the quality of surface water. In the process of detecting ammonia nitrogen content with Nessler’s reagent spectrophotometry method (HJ535—2009), water sample pretreatment (flocculation method), residual turbidity and instrument baseline drifting will bring uncertainty to the process. Accordingly, a spectroscopic method based on dual-wavelength (420 and 650 nm) measurement is proposed, so as to subtract the absorbance of residual turbidity and instrument baseline-drifting to eliminate such interference. We first figure out k, the turbidity correction coefficient of the water sample at the wavelength 420 nm, then divide the product of absorbance of 650 and k by the absorbance of 420, and finally obtain the net absorption of ammonia nitrogen chromogenic reaction. Thus we can make accurate quantitative detection of ammonia nitrogen content and evaluate the precision and accuracy of dual-wavelength spectrometry. The results shows that, with single-wavelength method, the relative deviation can be up to 8.67% caused by the filtration process of flocculation and sedimentation, while the dual-wavelength method would not be affected by the deviation, since dual-wavelength method includes no filtration process. The accuracy standard deviation of dual-wavelength method could be as low as 1.58%, and the recovery is between 98.5% and 103%, which shows that the method is more accurate and reliable. Compared with the current Nessler’s reagent spectrophotometric method, the present method not only omits the process of water sample pretreatment, but also avoids the interference of residual turbidity, which could significantly improve the efficiency of the experiment. Therefore, it is more suitable for rapid determination of ammonia nitrogen in large quantities of surface water samples.
2016 Vol. 36 (05): 1396-1399 [Abstract] ( 359 ) PDF (1338 KB)  ( 241 )
1400 Research on the Training Samples Selection for Spectral Reflectance Reconstruction Based on Principal Component Analysis
LI Chan,WAN Xiao-xia*,LIU Qiang*, LIANG Jin-xing, LI Jun-feng
DOI: 10.3964/j.issn.1000-0593(2016)05-1400-06
The composition of training samples set is an important influence factor of spectral reflectance reconstruction process. Representative color samples selection for learning-based spectral reflectance reconstruction is discussed in this paper. A method based on Principal Component Analysis (PCA) is proposed to perform sample selection. First of all, a part of samples are selected according to the minimum Euclidean distance criteria in terms of camera response value from a large number of samples, which aim to ensure the similarity between training samples and target samples. Then the PCA data processing method is applied to these samples after removing the duplicate samples. The samples with larger principal component loadings are regarded as the representative color samples. Different thresholds for each principal component are used to make decision whether the loading of sample is large enough. In order to validate the proposed method, the selected samples are used as training samples to recover the spectral reflectance of color patches. A real multi-channel imaging system by loading broadband color filters in front of lens is used in the experiment to acquire the multi-channel image dataset. In this paper the pseudo-inverse method is employed to reconstruct spectral reflectance of target color patches. It is shown that the proposed method is superior to the previous methods in spectral reconstruction accuracy and can meet the requirements of high precision color reproduction.
2016 Vol. 36 (05): 1400-1405 [Abstract] ( 327 ) PDF (3830 KB)  ( 203 )
1406 Monitor of Cyanobacteria Bloom in Lake Taihu from 2001 to 2013 Based on MODIS Temporal Spectral Data
LI Yao1, 2, ZHANG Li-fu1*, HUANG Chang-ping1, WANG Jin-nian1, CEN Yi1
DOI: 10.3964/j.issn.1000-0593(2016)05-1406-06
Algal bloom highly impacts the ecological balance of inland lakes. Remote sensing provides real-time and large-scale observations, which plays an increasingly significant role in the monitoring of algal bloom. Various Vegetation Indices (VIs) derived from satellite images have been used to monitor algae. With threshold segmentation of VI, the area of algal bloom can be extracted from images. However, the result of threshold segmentation only reflects the condition of algae when images were generated. Compared to separated VI data obtained at a particular moment of time, temporal spectral VI data contains phonological information of algae, which may be used to evaluate algal bloom more accurately and comprehensively. This study chose MODIS NDVI data of the Lake Taihu from 2001 to 2013, and constructed temporal spectral data for each year. Then, we determined the feature temporal spectra of severe cyanobacteria bloom, moderate cyanobacteria bloom, slight cyanobacteria bloom and aquatic plants, and separated these four kinds of objects using SVM (Support Vector Machine) algorithm, getting the spatial distribution and area of them. In order to compare the results of our method with traditional threshold segmentation method, we chose 8 separated NDVI images from the temporal spectral data of 2007. With the threshold 0.2 and 0.4, cyanobacteria bloom was classified into three degrees: severe cyanobacteria bloom, moderate cyanobacteria bloom, and slight cyanobacteria bloom. By comparison, it showed that our method reflected cyanobacteria bloom more comprehensively, and could distinguish cyanobacteria and aquatic plants using the phonological information provided by NDVI temporal spectra. This study provides important information for monitoring the algal bloom trends and degrees of inland lakes, and temporal spectral method may be used in the forecast of algal bloom in the future.
2016 Vol. 36 (05): 1406-1411 [Abstract] ( 374 ) PDF (2488 KB)  ( 189 )
1412 Synthesis of LaPO4∶Ce, Tb Fluorescent Nanopowders and Their Applications in Nondestructive Development of Latent Fingerprints
WANG Meng
DOI: 10.3964/j.issn.1000-0593(2016)05-1412-06
LaPO4∶Ce, Tb fluorescent nanopowders with high quality were synthesized via a hydrothermal method. The size, phase, and fluorescent property of as-prepared fluorescent nanopowders were then characterized by transmission electron microscopy (TEM), powder X-ray diffraction (XRD) measurements, and fluorescence spectroscopy (FS). The fluorescent nanopowders were well-dispersed and rod-like in shape, with an average diameter of about 20 nm and an average length of about 700 nm. The fluorescent nanopowders were of pure monoclinic LaPO4 structure. They could emit strong green fluorescence under the 254 nm ultraviolet excitation. The LaPO4∶Ce, Tb fluorescent nanopowders were finally used as novel fluorescent labels for the nondestructive development of latent fingerprints on various smooth substrates, and the developing contrast, sensitivity, selectivity, as well as the background interference were also discussed in detail. The experimental results showed that the latent fingerprints labeled by LaPO4∶Ce, Tb fluorescent nanopowders could give strong green emissions under 254 nm ultraviolet lights, and thus well-defined friction ridges with sharp edges and some detailed features could be clearly observed, with high contrast, high sensitivity, high selectivity, and low background interference. It was shown that our development procedure was facile, effective and well applicable with outstanding performance. More importantly, the extraction and detection of DNA in fingerprint residues could also be achieved after fingerprint development, which was almost impossible to achieve by using the traditional used developing powders including metal powder, metallic powder, and fluorescent powder. Therefore, our work provides beneficial references for the full utilization of both fingerprints and DNA evidences.
2016 Vol. 36 (05): 1412-1417 [Abstract] ( 289 ) PDF (4019 KB)  ( 160 )
1418 Research on Remote Sensing Inversion of Suaeda Salsa’s Biomass Based on TSAVI for OLI Band Simulation
LI Wei1,2, MU Meng1, CHEN Guan-bin1, LIU Wei-nan1, LIU Yuan1,2, LIU Chang-fa1,2
DOI: 10.3964/j.issn.1000-0593(2016)05-1418-05
Suaeda salsa(S.salsa) is a typical vegetation of coastal wetland in the north of Liaodong Bay. The S. salsa biomass assessment plays an important role in understanding the ecosystem productivity of coastal wetland and the formation of ecosystem structure and function. Usually the S.salsa coverage is inhomogeneous. The low S.salsa coverage can be found at a natural condition, the soil background has a strong influence on S.salsa spectral data. The Transformed Soil Adjusted Vegetation Index (TSAVI) used as independent variable was derived by the Landsat 8 OLI simulation data. The S.salsa biomass inversion models were built based on the regression analysis of TSAVI and ground measured biomass in this study. The correlation between TSAVI (600~687, 820~880 nm) and biomass was significant, the correlation coefficient was about 0.9, up to 0.92. The results of linear and quadratic models were better than those of logarithmic, exponential and power models, the determination coefficient r2 of linear and quadratic models were 0.83. Combined with F value and operation efficiency, the linear model was the best option for mature S.salsa biomass inversion. The linear model was applied to invert the S.salsa biomass by using the Landsat 8 OLI data in the study area and it was further validated using in-situ data. The correlation coefficient between the in-situ value and retrieved value was 0.962, the relative error was 0.106. For higher S.salsa coverage, the relative error was lower. The relative error of the low-cover S.salsa biomass inversion was around 0.18. The results showed that the established model has good accuracy for different coverage. In addition, with the introduction of ±5% error of soil line parameters a and b, the average relative errors were relatively stable, and the correlation coefficients were reduced, but all the correlative coefficients were above 0.9. The results showed that the established model is stable.
2016 Vol. 36 (05): 1418-1422 [Abstract] ( 271 ) PDF (2143 KB)  ( 144 )
1423 Identification of Strawberry Ripeness Based on Multispectral Indexes Extracted from Hyperspectral Images
JIANG Hao, ZHANG Chu, LIU Fei, ZHU Hong-yan, HE Yong*
DOI: 10.3964/j.issn.1000-0593(2016)05-1423-05
In order to establish new multispectral indexes for automatic identification of strawberry ripeness, hyperspectral imaging technology was applied in this paper. Eight indexes: Ind1=R730+R640-2×R680, Ind2=R680/(R640+R730), Ind3=R675/R800, IAD=log10(R720/R670), I1=R650/R550, I2=R650/R450, I3=R650/(R450+R550), I4=2×R650-(R550+R450) were calculated by extracting average spectral of strawberry samples and their identification effects of strawberry samples in three ripening stages(mature, nearly mature and immature) were judged with Fisher linear discriminant(FLD). The result showed that the identification effects of linear discriminant analysis model based on index I4 was the best among 8 indexes and the identification accuracy of modeling and prediction set was 90% and 91. 67% respectively. Three wavelengths (535, 675, 980 nm) related to strawberry ripeness were extracted based on average spectral of strawberry samples and 4 new indexes were established based on these three wavelengths: i1=2×R675- (R980+R535), i2=R675/(R980+R535), i3= (R675-R535)/(R675+R535), i4=[R675- (R535+R980)]/[R675+(R535+R980)]. The identification effects was judged with FLD and the results showed that the effects of linear discriminant analysis models based on i1, i2, i4 were better than index I4 and the identification accuracy of modeling and prediction set was 95.83%,95.83%,95.83% and 95%,95%,96.67% respectively. In conclusion, new established indexes i1, i2, i4 could be used in automatic identification of strawberry ripeness.
2016 Vol. 36 (05): 1423-1427 [Abstract] ( 354 ) PDF (3313 KB)  ( 244 )
1428 Inversion of Soil Organic Matter Content Using Hyperspectral Data Based on Continuous Wavelet Transformation
YU Lei1, 2, HONG Yong-sheng1, 2, ZHOU Yong1, 2*, ZHU Qiang1, 2
DOI: 10.3964/j.issn.1000-0593(2016)05-1428-06
Soil organic matter content (SOMC) is an important parameter that reflect soil fertility available for crop production, and monitoring of the SOMC dynamically has shown great importance to promote the development of precision agriculture. In recent years, many researchers have tried to use proximal soil sensing, especially using the proximal hyperspectral techniques to acquire different kinds of spectral data under the field and laboratory conditions, and various new algorithms are also introduced to build inversion models to predict SOMC from spectra for different regions and different kinds of soils. In this paper, the hyperspectral reflectance of different soil samples was measured using the ASD FieldSpec3 spectrum analyzer. At the same time, the SOMC of each soil sample was analyzed using potassium dichromate external heating method in the laboratory. The correlation analyses between raw soil spectral reflectance (R) and SOMC were done, and it could select sensitive wavebands reflectance when the determination coefficients (R2) exceeded 0.15. A continuous wavelet transform (CWT) was also performed on R and the continuum removal curves (CR) to generate a wavelet power scalogram in different scales, the correlation analyses were done between wavelet power coefficients and SOMC, and it could select the sensitive wavelet coefficients when the R2 exceeded 0.3. Then, after extracting wavebands reflectance from R and wavelet power coefficients from R-CWT, CR-CWT, the estimation models for SOMC had been successfully built by partial least squares regression (PLSR), BP neural network (BPNN), support vector machine regression (SVMR), respectively. The results showed that, compared to the R2 between SOMC and R, the R2 between SOMC and R- CWT, CR-CWT wavelet coefficients were increased by about 0.15 and 0.2. The CR-CWT-SVMR model was the best, its R2, RMSE and RPD value of validation set were 0.83, 4.02, 2.48, which could estimate SOMC comprehensively and stably. For the CR-CWT-PLSR model, although there was a slight gap in the prediction accuracy with that CR-CWT-BPNN and CR-CWT-SVMR models, it also had its own unique advantages: the model was simple and thus the computation speed was reduced significantly. In the future, the results can provide good potential for field proximal sensing researching.
2016 Vol. 36 (05): 1428-1433 [Abstract] ( 308 ) PDF (1958 KB)  ( 265 )
1434 Experimental Study on Soil Moisture Remote Sensing Based on Polarization Spectrum
YE Song1,DENG Dong-feng1,SUN Xiao-bing2,WANG Jie-jun1,WANG Xin-qiang1*
DOI: 10.3964/j.issn.1000-0593(2016)05-1434-06
As a novel remote sensing technique, polarimetric detecting technology is a useful supplement to traditional hyperspectral remote sensing technology, which provides more information for remote sensing. By taking advantage of the polarization characteristics of the surface reflecting light of soil with different moisture, the polarization spectral method is applied to measure soil moisture. The spectropolarimeter was used to measure the polarized reflectance spectrum of different soil moisture. The correlation between soil moisture and polarization spectrum was analyzed. The polarization characteristics of soil surface reflecting light in different viewing angles were surveyed by experiments. The experimental results show that: in the higher soil moisture conditions, the polarization spectrum and soil moisture have a certain connection, especially in the 500~700 nm band and soil moisture is directly proportional to the degree of polarization; but in low soil moisture conditions, the correlation of polarization spectrum and soil moisture is not obvious; in addition, the polarization spectrum are influenced by viewing angles, for example, when the incident angle of source light is fixed at 50°, while the viewing angle of instrument is between 20° and 60°, the degree of polarization increases with the viewing angle. When the viewing angle becomes wider,, the degree of polarization changed more significantly with the soil moisture.
2016 Vol. 36 (05): 1434-1439 [Abstract] ( 295 ) PDF (2575 KB)  ( 159 )
1440 Study on Photocatalytic Performance of LaPO4 Nanorods with Different Crystal Phases
WANG Kai1, 2, YAO Wen-qing1*, TENG Fei2*, ZHU Yong-fa1
DOI: 10.3964/j.issn.1000-0593(2016)05-1440-05
Rare earth phosphate has a wide application in optical materials, laser materials and many fields with great development prospects. In this paper, LaPO4 nanorods with different crystalline phases are prepared with hydrothermal method, its photocatalytic performance are discussed, as well as the structure and UV diffuse reflectance spectroscopy. The research indicates that the hydrothermal temperature plays a key role in the crystal phase, while it is hexagonal at 120 ℃, monoclinic at 180 ℃ and the mixed phase at 160 ℃. The UV absorption has no obvious change of each crystalline phase, and they all show nanorods. The photocatalytic activity of LaPO4 for the degradation of MB is studied; it is found that the monoclinic LaPO4 has the best photocatalytic activity. Furthermore, monoclinic LaPO4 could decrease the fluorescence quantum efficiency and increase the separation efficiency of electrons and holes, which improve the photocatalytic activity. Besides, the main active species are confirmed to be hydroxyl radicals with capture experiments during the photocatalytic process.
2016 Vol. 36 (05): 1440-1444 [Abstract] ( 319 ) PDF (3357 KB)  ( 503 )
1445 Automatic Assessment of Facial Nerve Function Based on Infrared Thermal Imaging
LIU Xu-long1, 2, FU Bin-rui1, 2, XU Li-wen1, LU Ning2, YU Chang-yong2, BAI Lu-yi2
DOI: 10.3964/j.issn.1000-0593(2016)05-1445-06
Facial paralysis which is mainly caused by facial nerve dysfunction is a common clinical entity. It seriously devastates a patient’s daily life and interpersonal relationships. A method of automatic assessment of facial nerve function is of critical importance for the diagnosis and treatment of facial paralysis. The contralateral asymmetry of facial temperature distribution is one of the newly symptoms of facial paralysis patients which can be captured by infrared thermography. This paper presents a novel framework for objective measurement of facial paralysis based on the automatic analysis of infrared thermal image. Facial infrared thermal image is automatically divided into eight regional areas based on facial temperature distribution specificity and edge detection, the facial temperature distribution features are extracted automatically, including the asymmetry degree of facial temperature distribution, effective thermal area ratio and temperature difference. The automatic classifier is used to assess facial nerve function based on radial basis function neural network (RBFNN). This method comprehensively utilizes the correlation and specificity of the facial temperature distribution,extracts efficiently the facial temperature contralateral asymmetry of facial paralysis in the infrared thermal imaging. In our experiments, 390 infrared thermal images were collected from subjects with unilateral facial paralysis. The results show: the average classification accuracy rate of our proposed method was 94.10%. It has achieved a better classification rate which is above 9.31% than K nearest neighbor (kNN) classifier and 4.87% above Support vector machine (SVM). This experiment results is superior to traditional House-Brackmann facial neural function assessment method. The classification accuracy of facial nerve function with the method is full compliance with the clinical application standard. A complete set of automated techniques for the computerized assessment of thermal images has been developed to assess thermal dysfunction caused by facial paralysis, and the clinical diagnosis and treatment of facial paralysis also will benefit by this method.
2016 Vol. 36 (05): 1445-1450 [Abstract] ( 342 ) PDF (2522 KB)  ( 555 )
1451 Automatic Method for Selecting Characteristic Lines Based on Genetic Algorithm to Quantify Laser-Induced Breakdown Spectroscopy
KONG Hai-yang1, 2, 3, SUN Lan-xiang1, 3*, HU Jing-tao1, 3, ZHANG Peng1, 2, 3
DOI: 10.3964/j.issn.1000-0593(2016)05-1451-07
Selecting proper characteristic lines from enormous spectral intensities is crucially important to implement quantitative analysis of Laser-Induced Breakdown Spectroscopy using internal standard method. Manual selecting of characteristic lines by researchers is time consuming and energy consuming, which cannot guarantee the best result. An automatic method to select analytical and reference lines for internal standard method from the original spectra based on Genetic Algorithm was proposed in this paper. This method was utilized to select analytical and reference lines for internal standard methods from LIBS of Mn, Ni, Cr, Si and Fe of low alloy steels. The optimal characteristic lines optimized by this method were the analytical line 403.306 8 nm of Mn and the corresponding reference line 368.745 7 nm of Fe, the analytical line 288.157 7 nm of Si and the corresponding reference line 427.176 1 nm of Fe, the analytical line 286.510 0 nm of Cr and the corresponding reference line 272.753 9 nm of Fe and the analytical line 352.453 6 nm of Ni and the corresponding reference line 358.698 5 nm of Fe, respectively. Then these elements were quantified by the internal standard method using these selected lines. The results showed that this proposed method for selecting characteristic lines can automatically select the optimal analytical and reference lines and could guarantee the best quantitative result obtained by internal standard method.
2016 Vol. 36 (05): 1451-1457 [Abstract] ( 388 ) PDF (2298 KB)  ( 213 )
1458 Review on Analytical Methods of Doping Elements in Synthetic Crystals
QIAN Rong, Siqin Bilige, DONG Jiang-li, ZHUO Shang-jun, GU Sui, SHENG Cheng, WANG Qun
DOI: 10.3964/j.issn.1000-0593(2016)05-1458-06
During the synthesis of crystal material, specific dopant can enhance the qualities and performance of crystals, while the types, concentrations and distributions of doping elements also have significant influence on the structures and properties of artificial crystals. Hence, it is very important to determine the concentrations of doping elements for further improving the crystal material formulas, crystal growth process, andits quality control. Currently, the analysis techniques for doping elements’ characterization include atomic spectrometry, X-ray fluorescence spectrometry, inorganic mass spectrometry, electron probe microanalysis, etc. The principles, advantages and disadvantages of these techniques are discussed in this paper. Considering the specialties and scope of application, it is necessary to choose the suitable methods to improve the efficiency and accuracy. Meanwhile, the developing trends of analysis methods for doping elements are also prospected.
2016 Vol. 36 (05): 1458-1463 [Abstract] ( 300 ) PDF (830 KB)  ( 182 )
1464 Study on the Detection of Trace Sulphur in Diesel with Inductively Coupled Plasma Optical Emission Spectroscopy
NIE Xi-du1, XIE Hua-lin2*
DOI: 10.3964/j.issn.1000-0593(2016)05-1464-04
The method to detect trace sulphur content in diesel with inductively coupled plasma optical emission spectrometry (ICP-OES) was established. Kerosene sample was directly diluted, and then trace sulphur content in the solution was analyzed directly with ICP-OES. High concentrations of organic solvents with high saturation vapor pressure can cause the increasing of the loading of plasma, which would interfere the determination. In order to keep the working stability of equipment, operating parameters, such as RF power, loading gas velocity, were being optimized. First, the axially-viewed technology was adopted to increase the sensitivity of determination. Second, the analysis spectral lines of sulfur are located in ultraviolet area; therefore the Ar was adopted as protective air, and increase Ar clean time to keep the pure of sight source. Third, the condensation and deposition of high concentrations of carbon could be avoided effectively by introducing O2 to plasma. Some detailed processes were used to further keep the stability of determinate signals such as: using element Y as internal standard to correct matrix effectives and compensate the errors caused by the spectral line shift, some automatic software were used to correct signal background. The results showed that the detection limits was 0.2 μg·L-1, the relative standard deviation (RSD) was in range of 1.6%~2.1%, and the recovery of the methods was in range of 97.4%~101.8%. The method has the following advantages: simple sample pretreatment, fast analyzing speed, low detection limitation, high precision and accuracy, as well as wide linear dynamic range. It can be used for rapid analysis of trace sulfur in diesel.
2016 Vol. 36 (05): 1464-1467 [Abstract] ( 326 ) PDF (1004 KB)  ( 200 )
1468 Study on the Inorganic Components Elements in Rare and Endangered Plant Alsophila Spinulosa
JIANG Bo1, TANG Li-Juan2, HUANG Jian-hua3*
DOI: 10.3964/j.issn.1000-0593(2016)05-1468-05
A method for simultaneously analysis of inorganic elements in rare and endangered plant spinulose tree fern was established. Alsophila Spinulosa samples were pretreated by using the hermetic microwave digestion. Six elements Na, Mg, Al, P, K and Ca were determined by using the inductively coupled plasma optical emission spectrometry (ICP-OES) and ten elements V, Cr, Mn, Fe, Ni, Cu, Zn, Cd, Hg and Pb were determined by using inductively coupled plasma mass spectrometry (ICP-MS). The working conditions were optimized as well. In order to keep the stability of the experiment, low concentration of HCl was added into the sample during testing. Multicomponent Spectral Fitting (MSF) and dynamic reaction cell (DRC) were used to correct the spectral interference and mass interference. Under optimized conditions, the standard linear relationships were satisfactory and the detection limit ranged from 1.87 ng·L-1~12.31 μg·L-1. Finally, the standard reference material NIST SRM 1 547 (peach leaves) was used to verify the proposed method. The obtained results were consistent with the reference method with the sameaccuracy and precision. Two Alsophila Spinulosa samples analysis results showed that Alsophila Spinulosa have higher concentrations of Na, Mg, K, Ca, Al, and P, and concentration of K is the highest. These results indicated that Alsophila Spinulosa have strong capability in K-enrichment. Alsophila Spinulosa have low concentrations of V, Cr, Mn, Fe, Cu, and Zn. Concentrations of Ni, Cd, Hg, and Pb are at very low trace levels, which indicated that the wild living environment is very healthy. This method has features of fast analyzing, high accuracy and convenience in operation, which can provide scientific basis for Alsophila Spinulosa inorganic elements contents measure.
2016 Vol. 36 (05): 1468-1472 [Abstract] ( 278 ) PDF (1157 KB)  ( 173 )
1473 Mapping Applications in Laser-Induced Breakdown Spectroscopy
CHEN Qi-meng, DU Min, HAO Zhong-qi, ZOU Xiao-heng, LI Jia-ming, YI Rong-xing, LI Xiang-you*, LU Yong-feng, ZENG Xiao-yan
DOI: 10.3964/j.issn.1000-0593(2016)05-1473-05
LIBS mapping was used to analyze and detect the elemental distribution of iron ore surface with self-developed software and 532 nm Nd∶YAG laser. Firstly, in order to illustrate the relationship between element content and spectral intensity, the calibration curve was established by scanning the surface of standard sample. Then, a self-made sample was homogeneously divided into three parts that was pressed by three different standard iron ore powders. For the purpose of validating the mapping technology, a two-dimensional concentration distribution profile was generated after scanning the sample surface which was compared with surface morphology phase of the sample. Finally, with the resolution of 100 microns, the surface scanning analysis of the natural iron ore within the scope of 14 mm×11 mm was implemented. With this basis, the distribution profile of the elements Ca, Al, Ti and Mn were obtained, and the analysis results were compared with the surface morphology phase of the natural iron ore. The results showed that LIBS mapping technology could be used to achieve the qualitative analysis of component gradient distribution of the heterogeneous sample surface.
2016 Vol. 36 (05): 1473-1477 [Abstract] ( 365 ) PDF (4734 KB)  ( 556 )
1478 The Study of Organic Nitrogen Uptake by Soil Microorganisms Using Gas Chromatography-Mass Spectrometry and Double Isotope Labeling Technique
YANG Li-jie1, 2, ZHANG Li-li1*, CHEN Wei1, 2, GONG Ping1, WU Zhi-jie1, XUE Yan1, 2, FANG Na-na1, WANG Ling-li1
DOI: 10.3964/j.issn.1000-0593(2016)05-1478-05
The direct absorption and utilization of low-molecular weight organic nitrogen (N) by soil microbial is a new subject in the research of microbial N nutrition. The study used gas chromatography-mass spectrometry to trace dual-labeled (13C, 15N) glycine from the soil solution and microorganisms. The results showed that glycine added to the soil was quickly taken up by soil microorganisms, with the half-life of glycine being 2.9 h. Withthe incubation of 4 h, the maximum amount of dual-labeled glycine in the microbial biomass was measured (equivalent to 10% of glycine added), indicating that added glycine was absorbed as intact molecular by soil microorganisms. The single labeled-Keto acid was detected in soil solution and in the microorganisms (decomposed production by double labeled glycine), but the content is extremely low, suggesting that added glycine mainly served as carbon (C) source for soil microbial life activities. This study demonstrated that compound specific stable dual labeled isotope analysis combined with chloroform fumigation technique was an effective method for detecting the low-molecular organic N utilized by soil microorganisms.
2016 Vol. 36 (05): 1478-1482 [Abstract] ( 295 ) PDF (1556 KB)  ( 186 )
1483 Adsorption Behavior of Pb(Ⅱ) Ion Imprinted Magnetic Composite Adsorbent in Aqueous Solution by FAAS
Lü Xiao-hua1, 2, ZHAO Meng-qi1, LI Jian-jun1, Ismayil Nurulla1*
DOI: 10.3964/j.issn.1000-0593(2016)05-1483-05
Pb(Ⅱ) Ion Imprinted Magnetic Composite Adsorbent (Pb(Ⅱ)-MICA) was prepared for the quick separation of Pb(Ⅱ) from aqueous solutions by bulk polymenrization with chitosan as the functional monomer, the magnetic iron oxide nano-particles as carrier and epichlorohydrin as the cross-link agent. The Pb(Ⅱ)-MICA and MNICA were characterized by FTIR. The Effects of the adsorption process including pH, contact time, initial concentration and temperature were investigated by FAAS. It was found that with the increasing of PH value, the adsorption capacity of Pb(Ⅱ)-MICA for Pb(Ⅱ) reached the peak in the range of pH 5.0~6.0. The maximum adsorption capacity was 32.48 mg·g-1 when the adsorption time was up to 120 min. The relative selectivity coefficient of Pb(Ⅱ) and other metal ion on Pb(Ⅱ) -MICA were 28.11, 91.14, 76.54, 33.06 times compared with MNICA. The results show that the Pb(Ⅱ)-MICA displayed strong affinity for Pb(Ⅱ) in the solution and exhibited selectivity for Pb(Ⅱ) ion in the presence of Cu2+,Cd2+,Ni2+ and Zn2+. The Langmuir adsorption isotherm models were fit to the adsorption equilibrium data well (r2=1, the saturation adsorption capacities were 33.87 mg·g-1). The adsorption dynamics and thermodynamics of Pb(Ⅱ) -MICA for Pb(Ⅱ) were investigated, the results indicated a Langmuir mono-layer mode process of Pb(Ⅱ) on the Pb(Ⅱ)-MICA was dominated by chemical action. An exothermic and spontaneous adsorption process of Pb(Ⅱ) on the Pb(Ⅱ)-MICA was driven by enthalpy.
2016 Vol. 36 (05): 1483-1487 [Abstract] ( 331 ) PDF (2233 KB)  ( 136 )
1488 Orthogonal Experiment for Optimization of the Sample Pretreatment Conditions for the Serum Cholesterol and Markers Determination by GC-MS
ZHANG Yu1, WANG Dong-fang1, CAO Bing1, LUO Shi-heng2, LIU Ya-qiong1, HUANG Ning-hua1, YAN Lai-lai1, WANG Jing-yu1*
DOI: 10.3964/j.issn.1000-0593(2016)05-1488-06
The objective is to use orthogonal experiment to optimize the pretreatment on the determination of serum cholesterol and its markers by GC-MS. And then the method is evaluated in a methodological perspective. The methodis to Use L16(211) orthogonal experiment design to observe the influence of three key steps,althogether seven factors of pretreatment, which are saponification (KOH ethanol solution concentration, temperature and time), extraction (dose) and derivatization (temperature , time and dose). As for the results,the conditions of optimal pretreatment are as follows:the ethanol solution is 1 mol·L-1 KOH, the saponification temperature is 70 ℃;the saponification time is 60 min;the Solvent quantity is 2 mL;the derivatization temperature is 70 ℃;the derivatization time is 60 min,and the derivatization agent is 100 μL. Through the optimization by orthogonal design and methodological evaluation, the determination of serum cholesterol and its markers by GC-MS is excellent in terms of accuracy and precision, and methodological evaluation indexes are better than those reported in other papers.
2016 Vol. 36 (05): 1488-1493 [Abstract] ( 299 ) PDF (933 KB)  ( 175 )
1494 Development of a Laser On-Line Cement Raw Material Analysis Equipment
LI Yu-fang1, 2, ZHANG Lei1, 2*, GONG Yao1, 2, ZHAO Shu-xia1, 2, ZHAO Yang1, 2, YIN Wang-bao1, 2, MA Wei-guang1, 2, DONG Lei1, 2, ZHANG Xiang-jie3, LI Yi4, JIA Suo-tang1, 2
DOI: 10.3964/j.issn.1000-0593(2016)05-1494-06
In engineering construction, cement quality directly affects the safety of construction projects. So it is necessary that we use qualified cement in the engineering structure. It is of great signification that a method detects cement raw material rapidly to adjust the mixture ratio of raw ores to ensure the cement quality. Traditional detection method needs sampling, sample preparation and test, etc. With many procedures, the test results are seriously lagged behind the production process. This paper introduces a set of online analysis equipment to determinate elemental composition of cement powder timely based on laser induced breakdown spectroscopy. This equipment is composed of a LIBS detection system and a pneumatic system. The equipment can achieve the real-time measurement for it needn’t sample preparation. Thus, it can guide cement raw material proportioning in time. In this paper, we have quantitatively analyzed the main components of Al2O3, CaO, Fe2O3, MgO and SiO2 in the cement raw materials using the full spectrum normalization method as well as the support vector machine. The corresponding maximum absolute errors were 0.34%, 0.35%, 0.07%, 0.14%, and 0.55%, respectively. Results showed that the measurement results of the newly developed LIBS equipment are in accord with those of the conventional chemical method. Furthermore, the measurement precision is in line with X-Ray fluorescence spectrometry. It is confirmed that the LIBS technique could be a prospect method for determination of elemental composition in the cement production industries.
2016 Vol. 36 (05): 1494-1499 [Abstract] ( 358 ) PDF (4092 KB)  ( 167 )
1500 Nondestructive Analysis of Jingdezhen and Longquan Celadon Wares Excavated from Nanhai No.1 Shipwreck
LI Ji-li1, HE Bin2, LIU Wei-dong1, 3, YAN Xin1, LIU Song1, LI Qing-hui1*
DOI: 10.3964/j.issn.1000-0593(2016)05-1500-08
The provenance study of ancient ceramics, as an important part in archaeological field, is the researching focus for researchers in scientific and technological archaeology. At present, the provenance study of ancient ceramics mainly depends on chemical analysis technologies while non-destructive physical structural analysis of ceramic glaze is relatively lacking. Therefore, it is difficult to have a comprehensive understanding of ancient ceramics. Optical coherence tomography (OCT) is an emerging non-destructive imaging technology with a high sensitivity. In this paper, the OCT combined with X-ray fluorescence spectroscopy (XRF) is employed firstly to analyze celadon wares of Jingdezhen and Longquan found in Nanhai No.1 shipwreck which is dated to early Southern Song dynasty non-destructively. First, the glaze cross-section structures and decoration characteristics of the celadon wares of the two kilns, Jingdezhen and Longquan,are studied by OCT.The type,thickness of glaze, the glaze inclusions including bubbles, crystals, residual grains, and the cracks on the glaze surface are analyzed based on the OCT images obtained. The characteristics of glaze cross-section structures for the celadon wares of two kilns are compared, and the decoration technologies of the celadon wares are also determined. Next, the chemical compositions of glaze and body of the celadon wares of the two kilns,Jingdezhen and Longquan, are obtained by XRF and compared. Then, the relationship between the differences of glaze cross-section structures and chemical compositions of glaze are discussed. The results show that the celadon wares from Jingdezhen and Longquan are different in glaze cross-section structures, and are the chemical compositions of the glaze and body. Meanwhile the differences of glaze chemical composition are relevant to the differences of glaze cross-section structures. This paper shows that the combination of OCT and XRF is validate as an effective method to identify the porcelains from different kilns.
2016 Vol. 36 (05): 1500-1507 [Abstract] ( 446 ) PDF (4601 KB)  ( 193 )
1508 The Characteristics and Significance of Deep Fault Gouge from the Weilasituo Zinc-Copper Polymetallic Deposit in Inner Mongolia
LUO Song-ying1, CAO Jian-jin1, 2*, YI Ze-bang1, JIANG Tao1, WANG Zheng-yang1
DOI: 10.3964/j.issn.1000-0593(2016)05-1508-06
The six groups of fault gouge samples were collected in different middle-sections from the underground mine of the Weilasituo zinc-copper polymetallic deposit, Inner Mongolia. The samples were analyzed with X-ray diffraction (XRD) and near infrared spectrum (NIR)to explore the mineral composition features of the fault gouges and their relationship with mineralization. The results are as follows: (1) The fault gouge samples contain the clay minerals which were formed in the low temperature alteration (such as montmorillonite, kaolinite, dickite, chlorite etc.), the alteration minerals in the medium temperature or high temperature hydrothermal environment (such as graphite, black mica, pyrophyllite, barite, serpentine, tremolite, actinolite etc.), and also the mineral compositions which were closely related to mineralization (such as copper-zinc oxide, copper-vanadium-chloride, azurite, bornite etc.). (2) The mineral compositions of the fault gouge from different depth are different. Shallow earth’s surface is mainly consisted of the low metamorphic minerals, and deep underground is mainly consisted of the high metamorphic minerals. (3) The mineral composition, mineral genesis and law of development of evolution of fault gouges suggest that, they were formed in the ore and metallogenic tectonic hydrothermal activity period, and had experienced the supergene oxidation later. (4) Through the analysis of the mineral compositions and alteration mineral assemblage characteristics of the fault gouges we can speculate that, the ore deposit was formed in medium-high temperature hydrothermal environment which had experienced the process of silicide, kaolinite, chloritization, hotaru petrochemical and sericitization alteration. Therefore, the analysis of the mineral compositions and mineral assemblage characteristics of the fault gouges,not only have certain practical significance for prospecting, but also can provide important reference information to study the genesis of the deposit.
2016 Vol. 36 (05): 1508-1513 [Abstract] ( 330 ) PDF (1734 KB)  ( 174 )
1514 Study on Technological Characteristic of the Proto-Porcelain on Western Zhou Dynasty Excavated from Zhouyuan Site in Shaanxi Province
ZHOU Yi-chen1, LING Xue1*, WEI Nü1, ZHONG Jian-rong2
DOI: 10.3964/j.issn.1000-0593(2016)05-1514-07
In southern region, the proto- porcelain have been found in large number and its excavation sites are relatively concentrated, thus its processing technique and origin have been studied thoroughly. However, as to proto-porcelain in northern region, the unearthed sites are scattered in distribution and its quantity is less. So there is limited analysis as to the technology. Since shaanxi zhouyuan relics unearthed a large number of proto-porcelain, it is necessary to give detailed analysis to them. In order to explore the technological characteristic of proto-porcelain of Western Zhou Dynasty which was excavated from Zhouyuan site in Shaanxi province, in this article three-dimensional video microscopy system was used to observe the microstructure and energy dispersive X-ray Fluorescence Spectrometer was used to test the chemical composition of the proto-porcelain body and glaze. The results of microscopic observation indicated that the proto-porcelain body quality was rough and had many unmelting particles and pores; the glaze layer was uneven and distributes many bubbles. The results of chemical composition in the body showed that the content of Al2O3 was between 11.8%~17.21%, SiO2 is 75%~80.5%, K2O is 3%~7.85%. However the content in the glaze of CaO is between 11.08%~23.94%, P2O5 is 1%~3.18%, MnO is 0.24%~1%; the content of MnO, P2O5, K2O in the glaze had improved greatly more than those in the body. The above results showed that the raw materials of proto-porcelain body may use the chinastone which contains more potassium; and the plant ash should be added in the calcareous glaze; the manufacturing characteristic of the proto-porcelain found in Zhouyuan site was still at the primary stage in Chinese porcelain’s history.
2016 Vol. 36 (05): 1514-1520 [Abstract] ( 270 ) PDF (2485 KB)  ( 157 )
1521 A New Redshift Measuring Method for Low-Quality Galaxy Spectra Based on Multi Resolution Fusion Distance
PAN Jing-chang1, LUO A-li1, 2, WEI Peng2, JIANG Bin1, LI Yin-bi2, ZHENG Qiang3
DOI: 10.3964/j.issn.1000-0593(2016)05-1521-05
The redshift measurement of galaxy spectrum is a key issue in large astronomical spectral survey. Its goal is to extract the redshift from spectrum, which is caused the Doppler Effect. With the development of the extragalactic sky survey project, the distance (redshift) of the observed targets is becoming further. As a result, the magnitude of the observed objects becomes darker and the spectral quality becomes poorer. Therefore, how to effectively and accurately measure the redshift from these low quality spectra is becoming an important problem in the extragalactic survey. Considering the spectral features and the data character, a new definition of multi-resolution fusion distance for low quality spectra is proposed. In this paper, we put forward a redshift measuring method for low quality galaxy spectra. This method combines the spectral features with different resolutions. The template spectrum and the spectrum to measure are reduced to the resolution and then a distance is computed by combining the offset of the above two spectra in different wavelengths.Then, a fusion distance is weighted averaged from the distances with different resolutions. In this paper, the effect of signal-to-noise ratio (SNR) on the measuring accuracy of the proposed method is discussed. The measuring accuracy is larger than 90% when the SNR is larger than 5. A large number of experiments show that the method proposedin this paper is very efficient in measuring the redshift of the low-quality galaxy spectra and the measuring error has nothing to do with the redshift value. The proposed method can be applied in redshift measurement of galaxies for the large-scale survey data.
2016 Vol. 36 (05): 1521-1525 [Abstract] ( 315 ) PDF (3241 KB)  ( 540 )
1526 Processing FBG Sensing Signals with Exponent Modified Gaussian Curve Fitting Peak Detection Method
CHEN Yong1, YANG Xue1, LIU Huan-lin2*, YANG Kai1, ZHANG Yu-lan1
DOI: 10.3964/j.issn.1000-0593(2016)05-1526-06
The system based on Fiber Bragg Grating (FBG) sensor is used in various fields, because of its advantages of high detection accuracy, good repeatability and adaptability. While the FBG sensor is a wavelength modulation type sensor, so the outside parameter detection is the center wavelength of FBG detection. At the same time, the FBG center wavelength corresponding to the peak value of the FBG reflection spectrum. Therefore, the core of demodulation system is the demodulation of FBG reflection spectrum during peak-seeking, and the high-precision peak detecting algorithm is the key technology of the system demodulation. The current peak detecting algorithms has a precondition for peak detection on FBG reflective spectrum, that the FBG reflective spectrum was a standard Gaussian model. But FBG reflective spectrum is not a standard Gaussian spectrum owing to the practical manufacture process and the individual environment; actually, it is an asymmetrical Gaussian spectrum. The experiment would achieve a lower accuracy because of this asymmetric property during peak-seeking. Based on the defect of the existing algorithm, an Exponent Modified Gaussian (EMG) Curve Fitting peak detecting algorithm is proposed in this paper. In the proposed algorithm, the coarse location was first determined by three times judgments and it can remove the false peak and peak invalid at the same time. Based on this, as the center of the coarse localization point to reconstruct the spectrum, and using the integral to judge the peak bias; then according to different peak bias, it revised the peak by the prepared exponential modified function. Simulation results show that at normal temperature or under variable temperature conditions, by comparing with direct peak searching algorithm, Gaussian fitting algorithm and the algorithm proposed by literature, the error of EMG peak detection algorithm is the minimum and high peak detecting precision. The algorithm proposed in this paper considers the FBG reflection spectrum characteristic of asymmetric effect. From its spectrum character, the EMG algorithm solves the problem of the limits of traditional peak detecting algorithm, meanwhile also guarantees a high-precision peak search results.
2016 Vol. 36 (05): 1526-1531 [Abstract] ( 369 ) PDF (3924 KB)  ( 375 )
1532 Study on the Determination System of Tissue Optical Properties Based on Diffuse Reflectance Spectrum
LI Chen-xi1, 2, SUN Zhe2, HAN Lei2, ZHAO Hui-juan1, 2*, XU Ke-xin1, 2
DOI: 10.3964/j.issn.1000-0593(2016)05-1532-05
The determination of tissue optical properties is the fundamental research field in biomedical optics. The ability to separately quantify absorption and scattering coefficients of tissue based on diffuse reflectance spectrum not only helps to gain physiological and structural properties of tissue but also provide insight into the mechanisms of tissue, which leads to the improvement in non-invasive detecting, image diagnosis and photodynamic therapy. In the paper, a flexible and rapid method is developed to extract the absorption and reduced scattering coefficients of turbid medium such as human tissue with diffuse reflectance spectrum. The diffuse reflectance spectrum is measured by the system which includes a white light source, a spectrometer, and a fiber optic probe for delivery and collection of light. The collection efficiency and system transfer function are researched based on the fiber probe geometry. This paper outlines a method based on empirical forward model and non-linear modeling inverse model to extract the optical properties from diffuse reflectance spectrum. The approach includes four steps: (1) generating diffuse reflectance spectra for training inverse model; (2) training the inverse model; (3) measuring and processing the diffuse reflectance spectra of samples; (4) predicting the optical properties of samples. Since the forward and inverse models could be regarded as non-linearity, the Artificial Neural Networks (ANN) is employed to develop the forward and inverse models. The principal component analysis (PCA) is also employed in the inverse model to decompress the data dimension and suppress the spectral noise. With a single fiber optic probe and spectroscopy system, the diffuse reflectance spectrum is measured and preprocessed. The accuracy and robustness of this method are evaluated by measuring the phantoms with a wide range of optical properties. The results indicate that the absorption and scattering coefficients could be extracted accurately by measuring the diffuse reflectance spectrum of single source-detector distance. The mean RMS percentage error is 4.58% and 7.92%, respectively. As to the application of extracting concentration of different chromosphere, it is better to include the absorption peak of every chromosphere within the measuring wavelength range. This method is valid for a wide range of optical properties with the advantage of rapid measurement and simple system setup, which is important for the clinical application.
2016 Vol. 36 (05): 1532-1536 [Abstract] ( 390 ) PDF (1344 KB)  ( 547 )
1537 Study on the Design of Prism Hyperspectral Imaging System Based on Off-Axis Two-Mirror Littrow Configuration
YANG Jin1, 2, CUI Ji-cheng1, Bayanheshig1, QI Xiang-dong1, TANG Yu-guo1*, YAO Xue-feng1
DOI: 10.3964/j.issn.1000-0593(2016)05-1537-06
In order to meet the requirements of high spectral resolution and high image quality on the hyperspectral imaging system, and to meet the new demands of miniaturization, light weight, and high optical efficiency in practical applications, a prism known as hyperspectral imaging system based on Littrow configuration is designed. The use of off-axis two-mirror Littrow configuration is to reduce the size of the optical system and provide a collimated beam for the plane prisms. To avoid the optical path interference, the macro programming optimization is applied. The application of two correct lens and aspheric mirrors can correct the spectral smile and the keystone of the hyperspectral imaging system. It is indicated that the distortion is less than 2.1 μm and the spectral bend is less than 1.3 μm, both are controlled within 18% pixel. The analytical results indicate that the MTF in the visible-near infrared(VNIR) spectral region from 400 to 1 080 nm is above 0.9 while spectrum resolution is about 1.6~5.0 nm, the spectral transmittance more than 51.5%. The results show that the system has high transmittance and image quality within the whole spectral range.
2016 Vol. 36 (05): 1537-1542 [Abstract] ( 292 ) PDF (3470 KB)  ( 187 )
1543 Study on Coaxial Linear Dispersion Triplet Prisms of Wide Spectral Imaging Spectrometer
LIU Bing1, 2, LIU Ying1, ZHANG Xiao-long3, LI Can1, WANG Jian1, LI Chun1*, SUN Qiang1
DOI: 10.3964/j.issn.1000-0593(2016)05-1543-06
To overcome the difficulties of complex structure and serious nonlinear dispersion in prismatic imaging spectrometer the coaxial linear dispersion prismatic imaging spectrometer is investigated in this paper. A mathematical model of symmetric triple prisms’ beam splitting system is constructed with prism’s dispersion equation, and the prisms assemble of direct view is obtained. Then the factors affecting dispersion linearity are analyzed. The refractive index and dispersion rate of prism material impact dispersion linearity most while the influence of incident angle is very small. The way to improve dispersion linearity is given and the refractive index condition meeting the requirement of dispersion linearity of prisms is obtained. It provides important basis to select the initial structure for coaxial linear dispersion triplet prisms of imaging spectrometer. On condition that the working band of 400~1 000 nm, center wavelength deviation angle 0°, the maximum dispersion angle 0.6°, object numerical aperture 0.15 and spectral resolution 5 nm, we succeed in designing coaxial linear dispersion triplet prisms. Digital simulation with ZEMAX is performed, and the results are in accordance with theoretical analysis.
2016 Vol. 36 (05): 1543-1548 [Abstract] ( 341 ) PDF (2234 KB)  ( 183 )
1549 The Research of Spectral Polarization Imaging Detection System Based Dual-AOTFs
ZHANG Rui1, 2, 3, CHEN You-hua1, 2, 3*, LI Shi-wei1, 2, 3, WANG Zhi-bin1, 2, 3*, WEN Ting-dun2, 3, WANG Yao-li1, 2, 3, LI Ke-wu1, 2, 3
DOI: 10.3964/j.issn.1000-0593(2016)05-1549-05
Acousto-optic tunable filter (AOTF) has the advantages of small size, good stability, wide range of wavelength scanning, quick modulation speed and so on. So AOTF is widely used in spectral imaging. But the detection of spectral polarization imaging is seldom found by using AOTF individually., Anew method of spectral polarization imaging based on dual-AOTFs is proposed. This method shows that the incident light is firstly divided into two beams by splitting mirror, and then two beams of light are through two AOTFs respectively, and the polarization direction of +1 diffraction order formed by AOTF is at a 45° against the other. The intensity of 0°, 45°, 90°and 135° can be obtained by ±1 diffraction orders of dual-AOTFs. Finally, the Stokes parameters are obtained by ±1 diffraction orders imaging of dual-AOTFs. They are S0 (the sum of light intensity between 0° and 90°), S1(the difference of light intensity between 0° and 90°) and S2 (the difference of light intensity between 45° and 135°). The target degree of linear polarization (DoLP) and angle of linear polarization (AoLP) is realized by corresponding theoretical formula. Furthermore, the polarization imaging of different wavelengths is realized with frequency sweep of dual-AOTFs so as to ultimately detect the spectral polarization imaging. The experiment has been verified through polarization imaging of three different lights, such as λ=500 nm, λ=550 nm and λ=600 nm.
2016 Vol. 36 (05): 1549-1553 [Abstract] ( 315 ) PDF (2536 KB)  ( 185 )
1554 Analysis and Design of Interference Imaging System in Fourier Transform Imaging Spectrometer Based on Multi-Micro-Mirror
Lü Jin-guang1, LIANG Jing-qiu1, LIANG Zhong-zhu1*, TIAN Chao1, 2, QIN Yu-xin1
DOI: 10.3964/j.issn.1000-0593(2016)05-1554-06
To realize the static state and high throughput of Fourier transform imaging spectrometer (FTIS), a temporal spatial mixed modulated FTIS based on multi-micro-mirror was put forward in this paper, whose interference system was based on Michelson interferometer with a multi-micro-mirror to replace the plane mirror. The remarkable characteristics of this FTIS were no movable parts and slit existing in this system, and the interferogram and image of object could be gained at the same time. The fore-optics system imaged the object on the plane mirror and multi-micro-mirror of the interference system, due to the structure feature of multi-micro-mirror, the optical path difference (OPD) of two imaging beam could be modulated. Through the reimaging system, the image of object with different interference order could be obtained. By means of the analysis to the spectrum signal-to-noise ratio (SNR) of interference system, the relationship between spectrum SNR and image SNR was definite, and the characteristic parameters of multi-micro-mirror were determined. To ensure the constancy of OPD corresponding to each step plane, by means of the analysis to the imaging process of fore-optics system, the optical path structure of telecentric in image space was determined. According to the calculation of the relationship between field of view and OPD, the design indexes of fore-optics system were determined and the optical design was completed. To ensure no extra OPD was introduced by reimaging system, through the analysis of the imaging feature by reimaging system, the optical path structure of double telecentric was determined. According to the calculation of the relationship between incidence aperture angle and step number, the optical system that satisfied the system requirement was designed. By means of the theory analysis and optical design to each unit system, this research can provide a novel development strategy for static and high throughput FTIS.
2016 Vol. 36 (05): 1554-1559 [Abstract] ( 336 ) PDF (1763 KB)  ( 221 )
1560 All-Fiber Mach-Zehnder Interferometer Based on Lateral-Offset and Peanut Shape Structure
SUN Ming-ming, WANG Jian-feng, JIN Yong-xing*, DONG Xin-yong
DOI: 10.3964/j.issn.1000-0593(2016)05-1560-05
A new in-fiber Mach-Zehnder interferometer (MZI) based on lateral-offset and peanut shape structure is proposed and demonstrated for the measure of curvature and liquid level. The sensor consists of lateral-offset structure and peanut shape structure. A section of single mode fiber (SMF) is spliced between them. A part of core mode in the single mode fiber is excited to cladding modes by lateral-offset. The cladding modes are re-coupled to the core mode by peanut-shape structure and get interference with the core mode. A high-quality interference spectrum with a fringe visibility of about 12 dB is observed. The effective refractive indices of cladding mode would change with the external environment parameters, which further bring about a shift of the interference fringes. The liquid level or curvature can be measured by record the shift of the valley, because the shift of the valley shows a linear dependence with the variation of the liquid level or curvature theoretically. In the water level experiment, the water level changes from 1.00 to 5.00 cm and the wavelength valley shows a red shift. The sensitivity of the MZI with a length of 6.10 cm is -0.68 nm·cm-1. In the curvature experiment, the curvature changes from 0.3 to 1.2 and the wavelength valley shows a blue shift. The sensitivity of the MZI with a length of 2.10 cm is 22.47 nm·m. The lateral-offset structure and peanut shape structure are spliced to fabricate the MZI. The sensitivity of the MZI is high, especially in the curvature measurement, it is higher than that of other fiber curvature sensors. Moreover the MZI presented in this paper has advantages of low cost and easy fabrication, which can be a potential application in the liquid level and curvature measurement.
2016 Vol. 36 (05): 1560-1564 [Abstract] ( 281 ) PDF (3033 KB)  ( 195 )
1565 Bidirectional Reflectance Distribution Function of Space-Borne Quartz Volume Diffuser
ZHAO Min-jie, SI Fu-qi*, LU Yi-huai, WANG Shi-mei, JIANG Yu,ZHOU Hai-jin, LIU Wen-qing
DOI: 10.3964/j.issn.1000-0593(2016)05-1565-06
Quartz Volume Diffuser(QVD) is used in the observing system of Space-Borne differential optical absorption spectrometer. The precision of observed solar spectrum directly influences the accuracy of the gas retrievals. Therefore the QVD is required for well Lambert feature to ensure the accuracy of full field solar spectrum, and it can provide uniformity source in the observing view of the instrument. Using bidirectional reflectance distribution function(BRDF) measurement instrument, adopting the powder pressboard of F4(polytetrafluoroethylene(PTFE)), QVD’s BRDF is measured by choosing the relative measurement method. Four kinds of QVD’s BRDF is obtained in the range of 180~880 nm, the observing view of -70°~+70°. Two kinds of QVD which has a well Lambert feature are selected by analyzing the QVD’s BRDF. The diffuse sunlight measured by QVD and F4 is compared, which show that QVD has well scattering properties with regard to solar spectrum and can be selected as the measuring diffuser. That supports for next Ultraviolet irradiation measurement, atomic oxygen erosion measurement and comparison measurement.
2016 Vol. 36 (05): 1565-1570 [Abstract] ( 279 ) PDF (2785 KB)  ( 147 )
1571 Spectrum Quantitative Analysis Based on Bootstrap-SVM Model with Small Sample Set
MA Xiao, ZHAO Zhong*, XIONG Shan-hai
DOI: 10.3964/j.issn.1000-0593(2016)05-1571-05
A new spectrum quantitative analysis method based on Bootstrap-SVM model with small sample set is proposed in this paper. To build the spectrum quantitative analysis model for bitumen penetration index, altogether 29 bitumen samples were collected from 6 companies. Based on the collected 29 bitumen samples, spectrum quantitative analysis model with proposed method for predicting bitumen penetration index has been built. To verify the feasibility and effectiveness of the proposed method, the comparative experiments of predicting the bitumen sample penetration index with the proposed method, partial least squares (PLS) and support vector machine (SVM) have also been done. Comparative experiment results have verified that the minimum prediction root mean squared error (RMSE) is achieved by using the proposed Bootstrap-SVM model with the small sample set. The proposed method provides a new way to solve the problem of building the spectrum quantitative analysis model with small sample set.
2016 Vol. 36 (05): 1571-1575 [Abstract] ( 240 ) PDF (877 KB)  ( 136 )
1576 A Comparison of Heterogeneous Reaction Kinetics of Oleic Acid Thin Film and Oleic Acid Coated Flyash with Ozone Using Vacuum FTIR
HE Xiang, LENG Chun-bo, ZHANG Yun-hong*
DOI: 10.3964/j.issn.1000-0593(2016)05-1576-05
Aerosol aging is the one of the research hotspots in the field of physical chemistry of atmospheric particulates at present. This study evaluates the impact of flyash in heterogenous reaction through the comparision of ozone oxidation reaction kinetics between the oleic acid (OA) thin film and oleic acid coated flyash which are observed by in situ vacuum FTIR for the first time. Except for the fingerprint region, the main bands of infrared spectrum of the fresh OA thin film and the fresh OA coated flyash are similar. When the two samples are exposed in the 20 ppm ozone concentration, room temperature and dry (RH~0%) conditions respectively, the =CH absorption peak (3 050 cm-1) decreases while The —OH stretch band (3 430 cm-1) increases. Moreover, The carboxylic C=O stretch band at 1 710 cm-1 decreases whereas a new ester group stretch band at 1 740 cm-1 appears and increases with increasing ozone exposure time. The OA component of the two samples can be gradually consumed and converted to some products containing hydroxyl and ester groups during the reactions through the changing trends of the infrared spectrum. The pseudo-first-order rate constant Kapp and the overall uptake coefficient γ, are obtained through changes in the absorbance of C=O stretching bands at 1 740 cm-1. The ozonolysis reaction rate constant of OA coated flyash is nearly double to the OA thin film. Since the surface area-to-volume ratio of OA coated flyash is larger than the OA thin film and the ozone concentrations are the same for the both reactions, the γ values for ozone uptake on OA thin film and OA coated flyash are (2.70±0.11)×10-4 and (3.70±0.13)×10-4. Rapid reaction rate of the flyash sample is due to the larger catalytic surface area and more valid catalytic effect compared to the OA thin film. This demonstrates that the flyash often easily leads to the secondary organic aerosols (SOAs) when the flyash unites with unsaturated organic acids and exposes to the ozone oxidation environment.
2016 Vol. 36 (05): 1576-1580 [Abstract] ( 264 ) PDF (2655 KB)  ( 133 )
1581 Study on the Water Transfer of Magnesium Acetate Aerosols Led by the Rapid and Slow Change of Relative Humidity
WANG Na, PANG Shu-feng*, ZHANG Yun-hong
DOI: 10.3964/j.issn.1000-0593(2016)05-1581-04
A combination of vacuum FTIR spectrometer (Vertex 80v, Bruker, German) and novel relative humidity (RH) adjusting equipment,which provides the pressure by pure water vapor, is used to study the hygroscopicity of magnesium acetate (Mg(CH3COO)2) aerosols. The RH can change not only rapidly but also slowly by the RH adjusting equipment.Because the RH is decided by the pure vapor, the real-time RH can be gained by calculating the integrated intensity of a feature band of vapor in an IR spectrum. Such the synchronism between FTIR spectrum and RH canbe ensured.The high-quality spectra of aerosols are obtained and the water peak and feature peaks of Mg(CH3COO)2 are analyzed during the slow and rapid RH changing process.The result shows that the areas of acetate ions and water decreases continuously at constant high RHs. After a slow cycle of RH (1.05×104 minutes), the water area decreases from 1.5 to 1.1, which means that the water content decreases after a cycle of RH. This phenomenon is reported at first up to date. The detailed analysis suggests that the hydrolysis of Mg(CH3COO)2 at high RH produces acetic acid, which was put out from the aerosols owing to the decrease of the pressure around the aerosols droplets. Furthermore, the dynamic hygroscopicity of Mg(CH3COO)2 aerosols is studied by changing RH as a pulse mode. It reveals that there is only water transfer hysteresis and no water loss after a pulse (10 seconds) when the RH is above 70%. Compared to slow process, it can be concluded that the hydrolysis reaction rate is slower than that of a pulse RH. The water transfer limited on rapid process should rise from some species on the surface of aerosols.
2016 Vol. 36 (05): 1581-1584 [Abstract] ( 257 ) PDF (2065 KB)  ( 163 )
1585 Interaction Study of Ferrocene Derivatives and Heme by UV-Vis Spectroscopy
HAN Guo-cheng, FENG Xiao-zhen, LIANG Jin-tao, XIAO Wen-xiang, CHEN Zhen-cheng*
DOI: 10.3964/j.issn.1000-0593(2016)05-1585-07
The interaction between ferrocene derivatives, such as Fc(COOH)2(λmax=286 nm), Fc(OBt)2(λmax=305 nm), Fc(Cys)(λmax=289 nm) and heme(λmax=386 nm) were studied by UV-Vis spectroscopy, respectively. The results show that, when the concentration of heme is fixed, the absorbance of heme increases with the increase of Fc(COOH)2 and Fc(Cys) concentration, the absorbance of heme almost keep the same when Fc(OBt)2 concentration increases; when the concentration of ferrocene derivatives are fixed, the absorbance of Fc(COOH)2 and Fc(Cys) also increases with the increase of heme concentration, the absorbance of Fc(OBt)2 almost keep the same when heme concentration increase. It is demonstrated that the hydrogen bonding interactions happen between Fc(COOH)2, Fc(Cys) and heme, none of Fc(OBt)2, the formation of hydrogen bonding lead to the growth of molecular chain, the bigger molecule can absorb more energy and increase the absorbance. Meanwhile, the stability of molecule is affected by the formation of hydrogen bonding, when the reaction time increases from 0.5 h to 18 h and 48 h, the absorbance at λmax=384 nm change from 2.64 to 2.53 and 2.51 with fixed concentration of Fc(COOH)2, the absorbance at λmax=384 nm change from 1.76 to 1.72 and 1.68 with fixed concentration of heme, the absorbance at λmax=397 nm change from 2.74 to 2.63 and 2.55 with fixed concentration of Fc(Cys), and the absorbance at λmax=397 nm change from 1.82 to 1.58 and 1.49 with fixed concentration of heme, respectively.
2016 Vol. 36 (05): 1585-1591 [Abstract] ( 380 ) PDF (3437 KB)  ( 199 )
1592 Application of Empirical Mode Decomposition and Independent Component Analysis for the Interpretation of Rock-Mineral Spectrum
WU Fang1, JIANG Xi-ping1*, YU Han-wen2, XIU Lian-cun3
DOI: 10.3964/j.issn.1000-0593(2016)05-1592-06
Rock-mineral spectrum is a mixture of varied mineral spectra, through which we can obtain information about its components quickly and conveniently without any damage to the sample. Empirical mode decomposition (EMD) cannot directly decompose source signals from information of the mixture, and independent component analysis (ICA) requires the number of mixed signals to be no less than the number of source signals. Combining these two methods, mixed signals can be decomposed using EMD method to obtain intrinsic mode function (IMF), while certain IMFs together with mixed signals can be used as input data matrix of ICA to obtain the source signals. This method overcomes the shortcomings of IMF and ICA. Studies have shown that, the higher content of source signals contained in the mixed signal, the better estimation can be obtained through EMD and ICA. The number of IMFs that participate in ICA decomposition determines the number of approximation of source signals. The accuracy of source signal estimation increases with the correlation coefficient between IMF and mixed signals. By applying this method to quantitative analysis of rock-mineral spectrum, information of the component minerals in rock-mineral can be obtained, which improves the efficiency of component analysis in detecting rock-minerals outside.
2016 Vol. 36 (05): 1592-1597 [Abstract] ( 261 ) PDF (944 KB)  ( 139 )
1598 Study on the Multi-Spectral True Temperature Pyrometer for Explosion Transient of Thermo-Baric Explosives
ZHANG Fu-cai1, SUN Xiao-gang1*, XING Jian2
DOI: 10.3964/j.issn.1000-0593(2016)05-1598-06
The high temperature and destructive power, made it difficult to test the explosion temperature of thermo-baric explosive. To effectively assess heat damage effect of thermo-baric explosive, multi-spectral high temperature measurement system is applied to transient high temperature test of thermo-baric explosive. The emissivity and the true temperature of explosion flame are calculated by using the secondary measurement method. In the data acquisition system, the test instrument achieves data collection and transmission 500 meters away in combination with optical fiber sensing technology and under the precondition to guarantee the participants safety. The measurement results show that the designed measurement system has the advantages of simple operation, high safety and better application prospect.
2016 Vol. 36 (05): 1598-1603 [Abstract] ( 261 ) PDF (1708 KB)  ( 159 )
1604 Native Defect Luminescence of Zinc Oxide Films and Its Potential Application as White Light Sources
LIU Shi1, CHEN Yong-jian1, CUI Hai-ning1*, SUN Sheng-nan1, WANG Zi-han1, WANG Hai-shui2
DOI: 10.3964/j.issn.1000-0593(2016)05-1604-11
ZnO light-emitting diodes (LEDs) have an enormous potential in lighting applications. The major issue to be resolved is the generating and control of light emissions. This issue arises from the variation and combination in LED wavelength. We found that defect luminescence of ZnO has a varied wide range of wavelength, which suits to an application of LED for white-light generation. We have shown both experimentally and theoretically that defect emission can be used in ZnO systems. This type of defect has the advantage of not requiring extensive and costly factory systems comparing with traditional doped materials and others. We not only propose potential application of native defect luminescence of Zinc Oxide film for white LEDs-flat light sources, but also have some methods to control defect origins, a certain center position and broad range of the emission band of ZnO film in the initial stage. According to different preparing method and certain experiment conditions, variant white such as whitish and bluish-white etc., primary and important colors- blue bands (455, 458 nm), green bands (517, 548 nm), red bands (613, 569 nm) are obtained respectively. This proved that it is a better road to one white light LED with one kind of material -ZnO.
2016 Vol. 36 (05): 1604-1614 [Abstract] ( 404 ) PDF (3468 KB)  ( 148 )
1615 Hyperspectral Models and Forcasting of Physico-Chemical Properties for Salinized Soils in Northwest China
XIAO Zhen-zhen1, LI Yi1,2*, FENG Hao2,3
DOI: 10.3964/j.issn.1000-0593(2016)05-1615-08
Hyperspectral remote sensing data have special advantages, i.e., they have high spectral resolution and strong band continuity, and a great number of spectral information could be widely used in soil properties monitoring research. Using hyperspectral remote sensing technique to analyze saline soil properties makes great significance for the crop growth in the irrigation district and agricultural sustainable development. 221 soil samples were collected from Manasi River Basin to measure soil electrical conductivity (EC), soil organic matter (SOM) and 3 kinds of cation concentrations including Na+, Ca2+ and Mg2+, which were used to obtain sodium adsorption ration value (SAR). The soil hyperspectral curves were also measured. EC, SOM and SAR models were established based on the six spectral-related indices, including raw reflectance (R), standard normal variable (SNV), normalized difference vegetation index (NDVI), logarithm of the reciprocal (LR), the first derivative reflectance (FDR) and continuum-removal reflectance (CR) by the stepwise linear regression method. The results showed that, compared to the other five models, the model of log (EC)~R had the highest accuracy with r value of 0.782 and RMSE value of 0.256. The model of SOM vs. NDVI had the highest accuracy with r value of 0.670 and RMSE value of 5.352. The model of SAR vs. FDR had the highest accuracy with r value of 0.647 and RMSE value of 1.932. As to the model accuracy of the studied soil physico-chemical properties, the log(Ec) model was the most effective one, followed by the SOM model, the SAR model was the most inaccurate. The sensitive wavelengths for EC, SOM and SAR distributed in 395~1 801 nm, 352~1 144 nm and 394~1 011 nm, respectively. Since soil physico-chemical properties were highly spatially variable, there were large differences for the model establishment and validation of the soil properties. This research could be a reference of hyperspectral remote sensing monitoring of salinized soils.
2016 Vol. 36 (05): 1615-1622 [Abstract] ( 268 ) PDF (1507 KB)  ( 189 )
1623 Color Enhancement by Diffusion of Beryllium in Dark Blue Sapphire
Kyungjin Kim1, Yongkil Ahn2
DOI: 10.3964/j.issn.1000-0593(2016)05-1623-06
Diffusion of beryllium was performed on dark blue sapphire from China and Australia. The samples were heated with beryllium as a dopant in a furnace at 1 600 ℃ for 42 h in air. After beryllium diffusion, samples were analyzed by UV-Vis, FTIR, and WD-XRF spectroscopy. After heat-treatment with Be as a catalyst, the irons of the ferrous state were changed to the ferric state. Therefore, reaction of Fe2+/Ti4+ IVCT was decreased. The absorption peaks at 3 309 cm-1 attributed to OH radical were disappeared completely due to carry out heat treatment. Consequently, the intensity of absorption band was decreased in the visible region. Especially, decreased absorption band in the vicinity of 570 nm was responsible for the lighter blue color. Therefore, we confirmed that the dark blue sapphires from China and Australia were changed to vivid blue.
2016 Vol. 36 (05): 1623-1628 [Abstract] ( 284 ) PDF (2613 KB)  ( 161 )
1629 Role of Interfacial Viscosity and pH in L-Phenylalanine, L-Tryptophan Molecular Rotors
N. Meenakshisundaram1, Kamatchi Sankaranarayanan2*
DOI: 10.3964/j.issn.1000-0593(2016)05-1629-05
Protein folding involves the aminoacid sequence to come forth and form an energy minimized structure. Recently molecular crowding leading to increase in viscosity is said to be one of the major concerns affecting protein folding. Many external fluorescent probes are used to detect such increases in viscosity. Since most of the protein sequences contain L-Phe and L-Trp, in this study we have used these aminoacids as probes to detect changes in viscosity. This study will help to advance the knowledge on molecular crowding effects in protein folding.
2016 Vol. 36 (05): 1629-1633 [Abstract] ( 262 ) PDF (2178 KB)  ( 160 )
1634 Novel and Validated Spectrophotometric Matrix Matching Method for Simple and Rapid Determination of Chromium in Oily Media
Feyzullah TOKAY*, Sema BADAT
DOI: 10.3964/j.issn.1000-0593(2016)05-1634-05
N,N’-bis(4-methoxysalicylidene) ethylenediamine is proposed as analytical reagent for the direct determination of chromium in original matrix of liquid oils. The method is based on the complexation of N,N’-bis(4-methoxysalicylidene) ethylenediamine and chromium in n-hexane∶acetone (1∶4) medium and spectrophotometric determination at 355 nm against reagent blank. Complexation of MSE and chromium is completed in 20 seconds at molar ratio 1∶1. The molar absorptivity and the formation constant of the complex are determined as 9 740 L·mol-1·cm-1 and 3.6(±0.1)×105, respectively. Beer’s law is obeyed in range 0.02~1.50 mg·L-1 chromium concentration. Limits of detection and quantification of the suggested method were 7.5 and 25.1 μg·kg-1, respectively. The accuracy and precision of the method was checked by finding mean recovery and relative standard deviation by oil-based chromium standard analysis as 96.4%±1.4% and 1.5%, respectively. The practical applicability of elaborate method was tested using oil-based chromium standard spiked and unspiked corn, sunflower, soybean, olive and canola oils.
2016 Vol. 36 (05): 1634-1638 [Abstract] ( 268 ) PDF (866 KB)  ( 165 )