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
2008 Vol. 28, No. 05
Published: 2008-05-29

 
       光谱学与光谱分析
961 THz Absorption Spectra of Several Carbohydrate Derivatives
YANG Li-min1,ZHAO Kui1,SUN Hong-qi2,ZHAO Guo-zhong2,YANG Guang-bin3,TIAN Wen4,WENG Shi-fu4, ZHANG Liang-liang2,WANG Yu-gang1,LU Xiang-yang1,XIE Da-tao1,XU Yi-zhuang4,ZHANG Cun-lin2, WU Jin-guang4,CHEN Jia-er1
DOI: 10.3964/j.issn.1000-0593.2008.05.045
Intermolecular hydrogen bond vibrations may be observed in the THz range. Carbohydrates are important bio-molecules, and are the typical systems for the study of hydrogen bonds. Carbohydrate derivatives have critical biological functions, and there are extensive hydrogen bond networks in molecular system, therefore, they would have various bands in the THz region. The THz absorption spectra of several carbohydrate derivatives were measured using a THz apparatus at room temperature. The THz bands are as follows: 1.17, 1.35, 1.93 and 2.23 THz for isopropyl-β-D-thioglucopyranoside; 1.93 THz for isopropyl-β-D- thiogalactopyranoside; 1.87 THz for methyl-(tetra-O-acetyl-β-D-galactopyranoside); 1.23, 1.70, 1.84 and 2.23 THz for O-(2,3,4,6-tetra-O-acetyl-β-glucopyranosyl)-N-hydroxysuccinimide. The results indicate that different samples have various bands that originated from collective modes of the whole molecules and especially isomers can be distinguished, showing that THz method is sensitive to the molecular structures and spatial configurations and is a helpful complement of IR spectroscopy.
2008 Vol. 28 (05): 961-965 [Abstract] ( 2395 ) PDF (1348 KB)  ( 534 )
966 Application of Terahertz Time Domain Spectroscopy to Explosive and Illegal Drug
LIU Gui-feng1,2,ZHAO Hong-wei1,GE Min1,2,WANG Wen-feng1*
DOI: 10.3964/j.issn.1000-0593.2008.05.046
Terahertz waves(THz, T-ray) lie between far-infrared and microwave in electromagnetic spectrum with frequency from 0.1 to 10 THz. Many explosives and illicit drugs show characteristic spectral features in the terahertz. Compared with conventional methods of detecting a variety of threats, such as weapons, explosives and illegal drugs, THz radiation is low frequency and non-ionizing, and does not give rise to safety concerns. Moreover, THz can penetrate many barrier materials, such as clothing and common packaging materials. THz technique has a great potential and advantage in antiterrorism and security inspection of explosives and illegal drugs due to the ability of high-sensitivity, nondestructive and stand-off inspection of many substances. The present paper summarizes the latest progress in the application of terahertz time domain spectroscopy (THz-TDS) to explosives and illegal drugs. Studies on RDX are discussed in details and many factors affecting experiments are also introduced.
2008 Vol. 28 (05): 966-969 [Abstract] ( 1903 ) PDF (775 KB)  ( 493 )
970 The Spectra Properties of 2-(2’-hydroxyphenyl)benzothiazole in Different Solvents
ZHENG Jia-jin1,2,ZHANG Gui-lan1*,WU Feng1,MA Li-na1,CHEN Wen-ju1
DOI: 10.3964/j.issn.1000-0593.2008.05.037
2-(2’-hydroxyphenyl)benzothiazole (HBT) is a typical compound with excited-state intramolecular proton transfer (ESIPT) effect. The mechanism of the influence of the solvent polarity on the ESIPT effect of HBT was investigated by means of absorption and fluorescence spectra in different polar solvents. The absorption spectra of HBT molecule in all solvents have the similar configuration and are mainly situated in the UV region from 260 to 370 nm. The absorption peaks are located at 287 and 335 nm and have the decline trend with the increase in the solvent polarity. In addition, there is a very weak absorption band at 400 nm and it is attributable to the absorption from the keto form of HBT. Under UV excitation at 335 nm, the fluorescence spectra in all the solvents were obtained. All the fluorescence spectra exhibit dual fluorescence peaks, which are located at 385 and 512 nm respectively. The former is attributed to the emission from the HBT enol forms, named the normal fluorescence, and the latter the emission from the keto tautomer emission, named ESIPT fluorescence. The fluorescence spectra of HBT show that the intensity of the normal fluorescence is obviously increased and the intensity of the ESIPT fluorescence is decreased with enhancing the polarity of the solvents. This indicates that the strong polar solvents are not favorable to the ESIPT of HBT. Because the solvated enols in the polar solvent prevent the ESIPT from happening, the ESIPT efficiency of HBT in cyclohexane is the largest and that of HBT in ethanol is the smallest. The three fluorescence bands of HBT in different polarity solvents were observed with 400 nm excitation. One fluorescence band at ca. 510 nm is referred to as the ESIPT fluorescence. This confirms that the weak absorption at 400 nm results from the keto tautomer and the enol and keto forms can coexist under the normal condition, but the enol form is the absolutely predominant. In addition, the other two unknown fluorescent emission bands appear at 436 and 456 nm respectively. Their possible origin is the emission from the deprotonated anion of HBT keto tautomer.
2008 Vol. 28 (05): 970-973 [Abstract] ( 206 ) PDF (775 KB)  ( 490 )
974 Radiative Transport and Collisional Transfer of Excitation Energy in Cs(6P) Atoms Mixed with N2
MENG Fan-xin1,2,QIN Chen1,DAI Kang1,SHEN Yi-fan1
DOI: 10.3964/j.issn.1000-0593.2008.05.053
Applying the CW laser absorption and fluorescence method, the cross sections for the fine structure mixing and quenching of the Cs(6P) state, induced by collision with N2 molecules, were measured. Cesium atoms were optically excited to the 6P3/2 state. The excited atom density and spatial distribution were mapped by monitoring the absorption of a counterpropagating single mode laser beam, tuned to the 6PJ→8S1/2 transitions, which could be translated parallel to the pump beam. The transmission factors, which describe the average probability that photons emitted within the fluorescence detection region can pass through the optically thick vapor without being absorbed, were calculated for 6PJ→6S1/2 transitions. The N2 caused line broadening and therefore increased the effective pumping rate and radiative rates. The effective radiative rates were calculated for the 6PJ6S transitions. The fluorescence intensity I895 of the sensitized 6P1/2→6S1/2 emission was measured as a function of N2 density in the range 2×101617cm-3 at a constant temperature T=337 K, which produced cesium density N0=1.25×1012cm-3. The transparency of the cell was obtained by the absorption of light beam passing the cell. The transparency is not a simple function of N2 density. It was found that the quantity N/I895 (I895 being corrected for the cell transparency) exhibited a parabolic dependence on N, confirming that the quenching of the 6PJ states is due to collision with N2 molecules instead of Cs ground state atoms. The coefficients of the second-order polynomial fitted through the measured data yielded the cross sections σ3/2→1/2=(0.42±0.17)×10-16 cm2 and σD=(1.31±0.52)×10-16 cm2 for the 6PJ fine-structure mixing and quenching, respectively, due to collision with N2 molecules. The quenching rate coefficient is about 3 times larger than the rate coefficient for the fine-structure mixing. Our values for these cross sections are in agreement, within combined error bars, with the values we have recently obtained under different experimental conditions.
2008 Vol. 28 (05): 974-977 [Abstract] ( 2294 ) PDF (617 KB)  ( 510 )
978 Study On Illuminant Spectrum Qualifications for Collecting Tongue Condition
SONG Xian-jie1,XU Chen-jie1,LIU Xiao-gu2,ZHANG Zhi-feng2
DOI: 10.3964/j.issn.1000-0593.2008.05.054
The traditional light sources in the diagnostic method of tongue collection such as daylight or even candles are easily affected by weather and environment. It isn’t favorable for doctors to obtain the accurate information of the tongue condition. The authors’ introduce the electric light sources to compensate or replace daylight to obtain stable and real tongue image and scientific results. Lighted by lamps with different radiation spectrum power distribution property, various color rendition and color temperature, the same object will indicate different colors. In this study, spectrum analysis is carried out on four fluorescent lamps and the research is based on iamge identification techniques of tongue color. Applying the methods of spectrum analysis, choose the best one in four illuminants with their specific spectrum by testing instruments and comparing with the results using several spectrum parameters and chromatic coordinates tolerance ellipses. Result showed PHILIPS YPZ220/18-3U.RR.D(with the correlative color temperature 6 500 K) lamp which has the most similar spectrum property with daylight can be used as standard lamp. The research provides the theoretic and experimental basis for choosing electric light sources to replace daylight.
2008 Vol. 28 (05): 978-982 [Abstract] ( 2120 ) PDF (1344 KB)  ( 524 )
983 A Method of Recognizing Biology Surface Spectrum Using Cascade-Connection Artificial Neural Nets
SHI Wei-jie1,YAO Yong1,ZHANG Tie-qiang2,MENG Xian-jiang3
DOI: 10.3964/j.issn.1000-0593.2008.05.002
A method of recognizing the visible spectrum of micro-areas on the biological surface with cascade-connection artificial neural nets is presented in the present paper. The visible spectra of spots on apples’ pericarp, ranging from 500 to 730 nm, were obtained with a fiber-probe spectrometer, and a new spectrum recognition system consisting of three-level cascade-connection neural nets was set up. The experiments show that the spectra of rotten, scar and bumped spot on an apple’s pericarp can be recognized by the spectrum recognition system, and the recognition accuracy is higher than 85% even when noise level is 15%. The new recognition system overcomes the disadvantages of poor accuracy and poor anti-noise with the traditional system based on single cascade neural nets. Finally, a new method of expression of recognition results was proved. The method is based on the conception of degree of membership in fuzzing mathematics, and through it the recognition results can be expressed exactly and objectively.
2008 Vol. 28 (05): 983-987 [Abstract] ( 2344 ) PDF (1023 KB)  ( 450 )
988 Spectral Properties of Two-Dimensional Photonic Crystal Quantum Well Structures
WANG Dong-dong,WANG Yong-sheng*,XU Zheng,DENG Li-er,ZHANG Chun-xiu,HAN Xiao
DOI: 10.3964/j.issn.1000-0593.2008.05.030
In the present paper, the spectral properties of two-dimensional (2D) photonic crystal quantum well structures were studied numerically. The structures consist of a 2D photonic crystal (PC) with square lattice of parallel dielectric circular columns in air and some middle layers of columns are removed. Similar to the electrons in semiconductor quantum wells, the photonic bandgap (PBG) in PC can act as a potential barrier to photons, which gives rise to quantized photonic states in the PBG region. Photonic band structures were calculated using plane wave expansion method and transmission spectra were obtained using transfer matrix method. The results show that discrete transmission peaks appear in PBG region. More transmission peaks arise with the increase of the well layer and the strength decreases with the increase in the potential layer width. The relationships between the frequency of transmission peaks and the width of well layer were also discussed.
2008 Vol. 28 (05): 988-990 [Abstract] ( 797 ) PDF (1811 KB)  ( 484 )
991 Effect of Spectra on Growth of Chlorella and Isochrysis
MAO An-jun1,WANG Jing1*,LIN Xue-zheng2, MENG Ji-wu1
DOI: 10.3964/j.issn.1000-0593.2008.05.032
Focusing on the speed and efficiency, the effects of different spectra on the growth of chlorella vulgaris and isochrysis galbana Parke 8701 were investigated by using monochromatic LED (light-emitting diode) and fluorescent lamp as light sources. It was concluded that continuous spectra accelerate the top-growth-rate, blue light has the best efficiency, and the combination of them can obtain a good balance of speed and efficiency. For the purpose of measuring spectra as a parameter of irradiation quantitatively, spectra-absorbability-coefficient defined as the quanta-absorbability- efficiency of spectra for algae was calculated by means of absorption spectra of algae and emission spectra of light sources. Compared with the experimental results the coefficients of different light sources have a positive correlation to their efficiency for growth, so the coefficient can be used to elementarily quantify the relation between the spectra and the efficiency for growth.
2008 Vol. 28 (05): 991-994 [Abstract] ( 1357 ) PDF (1338 KB)  ( 542 )
995 Model Building and Optimization of Ultrathin Silver Films by Spectroscopic Ellipsometry
CAO Chun-bin1,CAI Qi2,SONG Xue-ping2,SUN Zhao-qi2
DOI: 10.3964/j.issn.1000-0593.2008.05.043
Ultrathin silver films (4.0, 6.2, 12.5, 26.2, 30.0 and 40.6 nm) were prepared by direct current sputtering deposition. The thicknesses and optical constants of the films were studied by spectroscopic ellipsometry. The Drude model combined with Lorentz Oscillator model was used in the optimization of the ellipsometric data. The results show that surface plasma resonance absorption (SPR) peaks appear in the spectra of extinction coefficient k for samples 1, 2, 3 and 4. The peak shifts to shorter wavelength with the reduction in film thickness. The wavelengths of the SPR for different films were calculated by the SPR theory and also compared with the experimental data.
2008 Vol. 28 (05): 995-998 [Abstract] ( 1246 ) PDF (1084 KB)  ( 507 )
999 Spectroscopic Properties of Er3+-Doped Germanium Bismuthate Glass
ZHANG Yong,REN Guo-zhong,YANG Qi-bin,XU Chang-fu,LIU Yun-xin,SHANG Zhen-gang
DOI: 10.3964/j.issn.1000-0593.2008.05.051
Er3+-Doped Germanium Bismuthate Glass was fabricated and characterized. The absorption spectrum and up-conversion spectrum of glass were studied. The Judd-Oflet intensity parameters Ωt (t=2, 4, 6), determined based on Judd-Ofelt theory, were found to be Ω2 =3.35×10-20cm2,Ω4=1.34×10-20cm2,Ω6=0.67×10-20cm2 . Frequency up-conversion of Er3+-doped germanium bismuthate glass has been investigated. The up-conversion mechanisms are discussed under 808 nm and 980 nm excitation. Stimulated emission cross-section of 4I13/24I15/2 transition was calculated by McCumber theory. Compared to other host glasses, the emission property of Er3+-doped germanium bismuthate glasses has advantage over those of silicate, phosphate and germinate glasses. Er3+ -doped germanium bismuth glasses are promising upconversion optical and optic-communication materials.
2008 Vol. 28 (05): 999-1002 [Abstract] ( 451 ) PDF (841 KB)  ( 543 )
1003 Experimental Study on Glucose Solution by Laser-Induced Breakdown Spectroscopy
ZHANG Wen-yan,LIN Zhao-xiang*,SONG Shu-yan,CHEN Ya-guang,LIU Xiang-ming
DOI: 10.3964/j.issn.1000-0593.2008.05.052
The glucose solution was broken down by focusing the 1.064 μm beam of a Nd∶YAG laser, and the plasma was produced. The spectral signals were detected by an experimental setup including spectrograph and ICCD. The spectral line at 247.86 nm was identified as the characteristic of glucose by contrasting the spectra of glucose solution and pure water. Comparing the spectral intensities of three kinds of glucose solution with different concentrations (3%, 6% and 9%),the experimental result showed that the bigger the concentration,the stronger the spectral intensity,and the characteristic spectral intensities with the three concentrations present the trend of logarithm increase. At the same concentration, the time evolution curve of the characteristic spectra was obtained by changing the delay time of ICCD. It is concluded that the intensity of the characteristic spectra first increases and then decreases with the delay time. With the glucose solution concentration altering,the decay time of the characteristic spectra is nearly fixed,meaning that the decay time is independent of the concentration. The decay time of the characteristic spectra is about 300 ns. Furthermore,it was found that the characteristic spectral intensities of glucose solution with different concentrations reach the maximum at the same delay time.
2008 Vol. 28 (05): 1003-1006 [Abstract] ( 210 ) PDF (878 KB)  ( 573 )
1007 Observation and Simulation of Bi-Directional Spectral Reflectance on Different Type of Soils
CHENG Jie-liang,SHI Zhou*,LI Hong-yi
DOI: 10.3964/j.issn.1000-0593.2008.05.031
Knowledge of radiative transfer over bare soils is a prerequisite to addressing vegetation canopies and predicting soil properties by remote sensing. In the present study, the change in the spectral reflectance for three soils (i. e. red soil, paddy soil and coastal saline soil) with different view zenith and azimuth angles in the visible band (620 nm) and Landsat TM4 near infrared wavebands (760-900 nm) was measured in laboratory. The results showed that soil reflectance increased with increasing off-nadir view angle for all azimuth directions and soil bidirectional reflectance was azimuthally symmetric. The reflectance was highest in backscattering direction and lowest in forward-scattering direction. The bidirectional reflectance was simulated well using the Hapke model derived from the radiative transfer theory. The root mean square errors (RMSE) were 0.003, 0.002 and 0.004 and the correlation coefficients were 0.995, 0.998 and 0.998 in simulating bidirectional reflectance in visible wavebands for red soil, paddy soil and coastal saline soil, respectively; RMSE were 0.004, 0.006 and 0.005 and the correlation coefficients were 0.997, 0.996 and 0.998 in simulating bidirectional reflectance in NIR wavebands for these soils, respectively. It is stated clearly that Hapke model could be used to simulate the whole spectra curve, then to retrieve the soil surface characteristics.
2008 Vol. 28 (05): 1007-1011 [Abstract] ( 1397 ) PDF (909 KB)  ( 543 )
1012 The Effect of Temperature on the 4f5d Emission of Pr3+ in the Pr3+-Doped SrAl12O19
QI Shi-qun,HUANG Shi-hua,YOU Fang-tian,WANG Da-wei,GAO Chang-cheng
DOI: 10.3964/j.issn.1000-0593.2008.05.033
The emission spectra of SrAl12O19∶Pr3+ at temperature from 308 to 483 K were investigated under vacuum ultraviolet excitation. Both the dipole-forbidden 4f2→4f2 transition and the dipole-allowed 4f5d→4f2 transitions were observed. The intensity of the 4f5d→4f2 emission relative to that of the 4f2→4f2 emission increased with increasing temperature. A thermal equilibrium model was applied to the system consisting of the 1S0 state and the lowest 4f5d states of Pr3+, and the temperature dependence of emission spectra of Pr3+ in the Pr3+-doped SrAl12O19 was well explained.
2008 Vol. 28 (05): 1012-1015 [Abstract] ( 400 ) PDF (935 KB)  ( 508 )
1016 The Study of Ultra-Fine Diamond Powder Used in Magnetic Head Polishing Slurry
JIN Hong-yun,HOU Shu-en,PAN Yong,XIAO Hong-yan
DOI: 10.3964/j.issn.1000-0593.2008.05.044
In the present paper, atomic absorption spectrometry(AAS), inductively-coupled plasma mass spectrometry (ICP-MS), transmission electron microscopy (TEM), X-ray diffraction (XRD) and laser Raman spectroscopy (RM) were employed to study the commercial ultra-fine diamond powders prepared by the static pressure-catalyst method and used in magnetic head polishing slurry. The results of AAS and ICP-MS indicated that there were silicon oxide, Fe, Ni, Al and some other metal elements in the ultra-fine powders. XRD patterns showed the peaks of SiO2 at 2θ=35.6°, 39.4° and 59.7°and diamond sharp peaks in agreement with the results above. Diamond sharp peaks implied perfect crystal and high-hardness beneficial to high-efficiency in polishing. The broader Raman band of graphite at 1 592 cm-1 observed by Raman analysis proved graphite existing in the diamond powders. In the TEM images, the size of ultra-fine powders was estimated between 0.1 and 0.5 μm distributed in a wide scope, however, sharp edges of the powder particles was useful to polish. The ultra-fine diamond powders have many advantages,for example, high-hardness, well abrasion performance, high-polishing efficiency and being useful in magnetic head polishing slurry. But, the impurities influence the polishing efficiency, shortening its service life and the wide distribution reduces the polishing precision. Consequently, before use the powders must be purified and classified. The purity demands is 99.9% and trace silicon oxide under 0.01% should be reached. The classification demands that the particle distribution should be in a narrower scope, with the mean size of 100 nm and the percentage of particles lager than 200 nm not over 2%.
2008 Vol. 28 (05): 1016-1019 [Abstract] ( 1796 ) PDF (689 KB)  ( 480 )
1020 The Influence of Boric Acid Content on Luminescent Properties of SrAl2O4
WANG Guang-hui1,LIANG Xiao-ping1*,GU Yu-fen2
DOI: 10.3964/j.issn.1000-0593.2008.05.029
Long persistence phosphor powder of Eu2+, Dy3+ co-doped SrAl2O4 were prepared by combustion method. The influence of boric acid with different contents on the luminescent properties of Eu2+, Dy3+ co-doped alkaline earth aluminates were studied. To analyze the role of B2O3, phase identification was carried out by X-ray powder diffraction, emission spectra were recorded using a luminescence spectrometer, and luminescence photos were taken in a dark room after being excited by UV. The results indicated that the λem of the sample with content of 0.8 is 518 nm, which is the typical emission of Eu2+ 4f5d→4f and is a wide emission spectrum. There are two peaks in the emission spectra of the sample with content of 2, one is at 518 nm, and the other is at 487 nm, both of which are weak. The whole spectral line is a declining line. With the increase in boric acid content, the luminescence property and appearance character of Eu2+, Dy3+ co-doped strontium aluminates long persistence phosphor were different. In some range, with the increase in boric acid content, luminescence property and luminescence intensity were increased, and the sintering temperature was lowed.
2008 Vol. 28 (05): 1020-1022 [Abstract] ( 207 ) PDF (695 KB)  ( 522 )
1023 PEG Assisted Hydrothermal Synthesis of LaPO4∶Eu3+ Nanoparticles
ZHANG Wen-wen1,MENG Jian-xin2*,CAO Li-wei1,LIU Ying-liang2
DOI: 10.3964/j.issn.1000-0593.2008.05.034
The present reports a hydrothermal process to synthesize the precursor of Eu3+-doped LaPO4 nanoparticles with PEG2000 used as additive. SEM shows that the nanoparticles are similar to spheres. The Eu3+-doped LaPO4 phosphor was characterized by powder X-ray diffractometer. According to our measurements with XRD, the products belong to monoclinic monazite type, and the samples were well crystallized after sintering at 700 ℃ for 2 h. The effects of synthesis condition, sintering temperature and time on the luminescence of the samples were investigated. The luminescence data indicated that the optimum condition for synthesizing the precursor was at 180 ℃ for 14 h, and the optimum condition for heat-treatment of the precursor was at 850 ℃ for 1 hour. The effects of different contents of Eu3+ on the luminescence of LaPO4∶Eu3+ nanoparticles were also investigated, and the results showed that the luminescence intensity was enhanced with the slight increase in the Eu3+ content, and the optimum Eu3+-doping concentration was 4%(mole fraction).
2008 Vol. 28 (05): 1023-1025 [Abstract] ( 1440 ) PDF (944 KB)  ( 531 )
1026 Chemiluminescence Determination of 6-Mercaptopurine in the Luminol-Potassium Ferricyanide System
WANG Tao1, XUE Bing-chun1, LIU Er-bao1,2*
DOI: 10.3964/j.issn.1000-0593.2008.05.001
A novel chemiluminescence (CL) method to determine 6-mercaptopurine (6-MP) is described, based on the catalytic effect of 6-MP on the CL reaction of luminol with K3Fe(C-N)6 in a flow system. Under optimal experimental conditions, the calibration graph is linear in the range of 1.02×10-7 to 1.02×10-9 mol·L-1 6-MP. The linear regression equation was Y=36.315c+140.72, where Y is the relative emission intensity and c is the concentration of 6-MP expressed in 10-8 mol·L-1 and the correlation coefficient is 0.998 2 with the detection limits of 6.33×10-10 mol·L-1(S/N=3). CL peak-height precision is 3.54% of RSD(n=12) for a level of 2.0×10-9 mol·L-1. This method satisfactorily provides a fast, simple, sensible and favorable technique for the determination of 6-MP in synthesized samples in implementation. Moreover, the possible mechanism of CL enhancement was briefly discussed. Obviously, the reaction was related to the formation of free radicals. Thus, the CL emission could preliminarily be attributed to the process of energy transfer due to O2. radical and ·OH radical resulting from the oxidation product of 6-MP by K3Fe(CN)6, which acts as an active intermediate that reacts with luminol, leading to the formation of excited luminol molecule, which gives out an emission when it returns to its ground state.
2008 Vol. 28 (05): 1026-1029 [Abstract] ( 1358 ) PDF (786 KB)  ( 493 )
1030 Synthesis, Characterization and Antimicrobial Activity of Konjac Glucomannan Derivative with Quaternary Ammonium Salts
LEI Wan-xue1,2,XU Xia3,LIN Fang1,YANG Qin-huan1,LI Zhen-jun1,ZHANG Ting-you1*
DOI: 10.3964/j.issn.1000-0593.2008.05.015
Methacryloxylethyl tetradecyl dimethyl ammonium bromide was grafted onto konjac glucomannan using ceric ammonium nitrate as an initiator, and the konjac glucomannan derivative with quaternary ammonium salts was obtained. The konjac glucomannan derivative was investigated by hydrogen nuclear magnetic resonance spectroscopy (1H NMR), Fourier transform infrared spectroscopy (FTIR), differential scanning calorimeter (DSC), and Zeta sizer nano series. The antimicrobial properties of the konjac glucomannan derivative against selected microorganisms were tested by the quantitative suspension method. The results revealed that (1) methacryloxylethyl tetradecyl dimethyl ammonium bromide can be grafted onto the surface of the konjac glucomannan, and the percentage grafting increases with increasing the amount of methacryloxylethyl tetradecyl dimethyl ammonium bromide. (2) The Zeta potential showed that the isoelectric point of the konjac glucomannan and the modified konjac glucomannan is pH 4.5 and pH 9.9, respectively. The shift of the isoelectric point is due to the quaternary ammonium groups. (3) The obtained konjac glucomannan derivative has significant inhibition effect on the growth of microorganisms, and the bactericidal rates in 15 min for E.coil (8099), S. aureus (ATCC 6538) and C. albicans (ATCC10231) were 99.99%, 99.99% and 98.13%, respectively.
2008 Vol. 28 (05): 1030-1034 [Abstract] ( 165 ) PDF (1105 KB)  ( 538 )
1035 Infrared Study on Adsorption of O3 at SnO2 Surface
ZENG Yu-feng1,3,LIU Zi-li1,2*,QIN Zu-zeng1,LIU Hong-wei4
DOI: 10.3964/j.issn.1000-0593.2008.05.003
SnO2 was prepared by precipitation method and mental oxides modified SnO2 catalysts were prepared by coprecipitation method. High concentration molasses fermentation wastewater degradation by SnO2 catalyzed ozonation was used as a probe reaction and IR spectra were used to study the adsorption of O3 at SnO2 and different metal oxides modification SnO2 surface. The results showed, that in the infrared absorption spectra of adsorption of O3 prepared by pure O2 at SnO2 catalyst surface, two obvious bidentate absorption double peaks were found at 1 027 and 1 055 cm-1, and 2 099 and 2 122 cm-1, respectively. However, there was competitive adsorption between O3 prepared by air, and CO and CO2. Then the O3 adsorption decreased, leading to the decrease in the degradation of molasses fermentation wastewater by SnO2 catalytic ozonation, and after 60 min reaction, the degradation rate by pure oxygen as oxygen source was 79.2%. It was 33.1% more by air as oxygen source. Similar strength adsorption peaks in the infrared spectra were found at 2 236, 2213 cm-1 and 1 628, 1 599 cm-1 with Fe2O3, NiO, CuO, ZnO, MgO, SrO and BaO modified SnO2. But the adsorption of CO2 and CO was different on modifier-SnO2, There was a wide absorption peak at 1 580-1 070 cm-1 in the infrared spectra of transition metal modified SnO2, and two new peaks at 1 298 and 1 274 cm-1 were found between 1 580 and 1 070 cm-1 in the infrared spectra of alkaline-earth metals modified SnO2 catalysts. These changes leaded to a different catalytic ozonation activity of modifier-SnO2, the results of molasses fermentation wastewater degradation by ozone combined with alkaline-earth metal modified SnO2 was obviously better than ozone combined with transition metal modified SnO2. And among them, the ozonation catalytic activity of BaO-SnO2 was the best.
2008 Vol. 28 (05): 1035-1038 [Abstract] ( 2752 ) PDF (1010 KB)  ( 529 )
1039 The Structure and Properties of Metal-Free 1,8,15,22-Tetrakis (3-Pentyloxy) Phthalocyanine Complex and Study of Its IR spectra
ZHOU Hong1,XIE An-jian2
DOI: 10.3964/j.issn.1000-0593.2008.05.042
Density functional theory calculations were carried out to study the molecular structure, molecular orbital, atomic charge, and infrared spectra of metal-free 1,8,15,22-tetrakis(3-pentyloxy) phthalocyanine using B3LYP method with the 6-31G(d) basis set. The optimized molecular geometry is in good agreement with the result from X-ray deterimination, and the differences between the bond lengths from calculation and X-ray crystallography structure for the framework of phthalocyanine are less than 0.002 nm. It was also found that there is a good consistency between the calculated and experimental IR data. The calculated structure and IR spectra were fairly compared with the X-ray crystallography structure and experimental IR spectra to verify the reliability of employed B3LYP method and 6-31G(d) basis set. It is worth noting that the 3-pentyloxy groups at the alpha position have significant influence on the structure and properties of metal-free pthalocyanine, for example, both the energies of HOMO and LUMO increase, however, the gap between HOMO and LUMO decreases, which results in the decrease of the 1,8,15,22-tetrakis(3- pentyloxy)phthalocyanine stability. The important peaks in the IR spectra were also assigned and analyzed in detail according to the calculations.
2008 Vol. 28 (05): 1039-1044 [Abstract] ( 1722 ) PDF (1150 KB)  ( 458 )
1045 Determination of Main Fiber Compositions of Alfalfa Hay by Near Infrared Reflectance Spectroscopy
NIE Zhi-dong1,HAN Jian-guo1*,YU Zhu1,ZHONG Yong2,LIU Fu-yuan2
DOI: 10.3964/j.issn.1000-0593.2008.05.041
Sixty alfalfa samples, with different growth stage, cultivars, and preparing method (drying by oven, shade and sun), were selected to study the potential of determination of cellulose, hemicellulose and lignin content in the present research. The result showed that the correlation coefficient of cross-validation (RCV), determination coefficient of external validation(r2) and the ratio of standard deviation to root mean square error of prediction(RPD) of cellulose and lignin were 0.97, 0.97 and 4.44, and 0.94, 0.94 and 4.08, respectively. This indicated the feasibility of determining cellulose and lignin content of alfalfa using near infrared reflectance spectroscopy. Hemicellulose was not predicted accurately by NIRS in this study, due to the lowest accuracy (RCV=0.39, r2=0.29, RPD=1.09). The exact determination of cellulose and lignin using near infrared reflectance spectroscopy will be useful to quality control in alfalfa production and quickly analyzing the fiber composition of alfalfa samples in breeding research.
2008 Vol. 28 (05): 1045-1048 [Abstract] ( 1840 ) PDF (648 KB)  ( 551 )
1049 The Study of Infrared Absorption Spectrum of Diamond during Growth by FTIR
ZHANG Xian-hui1,2,FENG Ke-cheng1,SUN Yue1,WANG Xing-quan1,SUN Xiu-ping1,YANG Si-ze2
DOI: 10.3964/j.issn.1000-0593.2008.05.040
The diamond thin films were deposited on silicon substrates under invariable conditions of process pressure, substrate temperature negative direct-current (dc) bias of substrate and microwave power while the rations of methane (CH4) to hydrogen (H2) changing from 3% to 5% and 9% using electron-cyclotron-resonance microwave plasma-assisted chemical vapor deposition technique(ECRCVD). In situ Fourier transform infrared spectroscopy (FTIR)have been used to study the plasma species absorbed on the substrate surfaces as well as the species above the substrates surfaces both before and during the nucleation and film growth. It is demonstrated that these techniques canprovide useful information on the early stages of diamond growth. When correlated with film properties measured by Raman spectroscopy and scanning electron microscopy, the results from FTIR indicate that the absorption of the graphitic and diamond phases are related to the ratio of CH4 to H2 and can be identified at the early stages of film growth.
2008 Vol. 28 (05): 1049-1051 [Abstract] ( 1155 ) PDF (972 KB)  ( 531 )
1052 A Method of Eliminating the Water Vapor Interference Simultaneously in Open Path FTIR Measurement by Instrumental Line Shape Correction
XU Liang,LIU Jian-guo,GAO Min-guang,LU Yi-huai,LIU Wen-qing,WEI Xiu-li,ZHANG Tian-shu,CHEN Hua,LIU Zhi-ming
DOI: 10.3964/j.issn.1000-0593.2008.05.035
Water vapor absorption, which exists in mid-infrared region, is an interferential element for infrared spectra analysis. A new method, which can be used to eliminate the water vapor interference in FTIR measurement, is presented. To calculate the high resolution absorbance of water vapor, a fast line by line method which computed with the HITRAN database (eg. line strength, self broadening, air broadening, etc) and meteorological parameters (eg. temperature, pressure, and relative humidity) was used. After convolving with Instrumental line shape (eg. divergence angle, resolution, etc), the absorbance of water vapor was then transferred from high resolution to low resolution, which matched the instrumental parameters. After the acquirement of water vapor absorbance spectrum, it will be subtracted from the measured spectrum to calculate the spectrum with the water vapor was eliminated. In the present work, analysis of measured data from open path FTIR is described. Only the absorbing character and noise was left in the spectrum after eliminating the water vapor interference. Consequently, this method has an ideal effect on water vapor elimination when there is no dryer can be used, especially in the case of open path FTIR measurement.
2008 Vol. 28 (05): 1052-1056 [Abstract] ( 1569 ) PDF (1170 KB)  ( 463 )
1057 Applied Study on Clustering of Variables around Latent Components Method in Wavelength Region Selection with Near-Infrared Spectroscopy
BAO Feng-wei1,PENG Qian-rong2*,LIU Jing-yan3,CAI Yuan-qing2,MAO Han-bing2, TANG Ke2,Lü Yan-wen2
DOI: 10.3964/j.issn.1000-0593.2008.05.004
The present paper introduced the principle of clustering of variables around latent components method ,and used this method in selecting spectrum range of the NIR quantitative analysis models. Taking tobacco samples as experiment materials, we dealed with 107 sample spectra, divided the spectra into 5 clusters, and explained the information reflected by each of these 5 clusters in terms of chemistry. On this basis, we chose the corresponding wavelength range to set up the quantitative models of the total sugar, reducing sugar and nicotine by PLS method. Compared with the model based on the full NIR spectral range, Rtraining of the models based on the chosen spectral range rose from 0.977 1,0.917 2 and 0.987 4 to 0.995 5,0.975 1 and 0.994 4;Rtest rose from 0.977 8,0.941 2 and 0.993 2 to 0.992 7,0.967 9 and 0.994 0;RMSECV dropped from 1.09,1.43,0.14 to 1.05,1.05 and 0.13, RMSEP dropped from 0.92,1.17 and 0.16 to 0.39,0.63 and 0.11 and the D value dropped from 1.274%,1.972% and 0.829% to 0.711%,0.843% and 0.768% for the total sugar,reducing sugar and nicotine, respectively. These data indicated that this method can improve the forecasting precision and stability of the model, so offers certain guidance on practical application.
2008 Vol. 28 (05): 1057-1061 [Abstract] ( 485 ) PDF (702 KB)  ( 495 )
1062 Application of Vis/NIR Diffuse Reflectance Spectroscopy to the Detection and Identification of Transgenic Tomato Leaf
XIE Li-juan,YING Yi-bin*,YING Tie-jin,TIAN Hai-qing,NIU Xiao-ying,FU Xia-ping
DOI: 10.3964/j.issn.1000-0593.2008.05.047
The feasibility of Vis/NIR spectroscopy technique for rapid and non-invasive detection of transgenic tomato leaves from conventional ones was investigated by means of spectral diffuse reflectance mode. A total of 68 samples (38 transgenic ones and 30 non-transgenic ones) were used for classification. The calibration and validation results were analyzed via discriminant analysis (DA) and partial least squares (PLS) discriminant method using TQ 6.2.1 quantitative software. Models based on the different spectral pre-processing methods (multiplicative signal correction (MSC), first and second derivative) were compared. It was found that the classification accuracy using DA was higher than that using PLS and the best results were gained by using spectra after MSC with InGaAs detector and the classification accuracy was 89.7% (accuracy of 86.8% for transgenic samples and 93.3% for non-transgenic ones). The results show that Vis-NIR diffuse reflectance spectroscopy technique is a feasible and fast method for non-invasive detection of transgenic and non-transgenic tomato leaves.
2008 Vol. 28 (05): 1062-1066 [Abstract] ( 1285 ) PDF (848 KB)  ( 512 )
1067 FTIR Spectroscopic Characterization of Chromium-Induced Changes in Root Cell Wall of Plants
ZHANG Xiao-bin,LIU Peng*,LI Dan-ting,XU Gen-di,JIANG Min-jiao
DOI: 10.3964/j.issn.1000-0593.2008.05.025
Due to its wide industrial use, chromium is considered a serious environmental pollutant. Contamination of soil and water by chromium (Cr) is of recent concern. Chromium mainly accumulates in root in plants, and the change in compounds of the root cell wall have a close relation with the Cr accumulation. Compared with the other identification methods, the identification of the Chinese traditional and herbal drugs using Fourier transform infrared spectrometer with OMNI collector is simple and convenient, fast and accurate. In the present paper, the spectra of cell wall of Cr-treated root and control of Eichhornia crassipes and Alternanthera philoxeroides were determined. Absorption peaks were identified to the corresponding functional groups and half-quantitative analysis was also used. The results showed that a significant shift of —OH absorption peaks can be seen when comparing the FTIR spectra of control and Cr-treated plants, and the absorbency of —OH and COO- groups went up in E. crassipes root cell wall while droped in A. philoxeroides root cell wall. It is suggested that —OH and COO- groups were referred in binding Cr6+ in aqueous solutions, and this may be included in the mechanism of Cr accumulation in E. crassipes roots. Therefore, FTIR spectrometry could be widely used to monitor changes in chemical composition of plant parts under stresses and environmental restoration.
2008 Vol. 28 (05): 1067-1070 [Abstract] ( 543 ) PDF (721 KB)  ( 406 )
1071 Application of Infrared Spectroscopy Technique to Protein Content Fast Measurement in Milk Powder Based on Support Vector Machines
WU Di,CAO Fang,FENG Shui-juan,HE Yong*
DOI: 10.3964/j.issn.1000-0593.2008.05.038
In the present study, the JASCO Model FTIR-4 000 fourier transform infrared spectrometer (Japan) was used, with a valid range of 7 800-350 cm-1. Seven brands of milk powder were bought in a local supermarket. Milk powder was compressed into a uniform tablet with a diameter of 5 mm and a thickness of 2 mm, and then scanned by the spectrometer. Each sample was scanned 40 times and the data were averaged. About 60 samples were measured for each brand, and data for 409 samples were obtained. NIRS analysis was based on the range of 4 000 to 6 666 cm-1, while MIRS analysis was between 400 and 4 000 cm-1. The protein content was determined by kjeldahl method and the factor 6.38 was used to convert the nitrogen values to protein. The protein content value is the weight of protein per 100 g of milk powder. The NIR data of the milk powder exhibited slight differences. Univariate analysis was not really appropriate for analyzing the data sets. From NIRS region, it could be observed that the trend of different curves is similar. The one around 4 312 cm-1 embodies the vibration of protein. From MIRS region, it could be determined that there are many differences between transmission value curves. Two troughs around 1 545 and 1 656 cm-1 stand for the vibration of amide Ⅰ and Ⅱ bands of protein. The smoothing way of Savitzky-Golay with 3 segments and zero polynomials and multiplicative scatter correction (MSC) were applied for denoising. First 8 important principle components (PCs), which were obtained from principle component analysis (PCA), were the optimal input feature subset. Least-squares support vector machines was applied to build the protein prediction model based on infrared spectral transmission value. The prediction result was better than that of traditional PLS regression model as the determination coefficient for prediction (R2p) is 0.951 7 and root mean square error for prediction (RMSEP) is 0.520 201. These indicate that LS-SVM is a powerful tool for spectral analysis. Moreover, the study compared the prediction results based on near infrared spectral data and mid-infrared spectral data. The results showed that the performance of the model with mid-infrared spectral data was better than the one with near infrared spectra data. It was concluded that infrared spectroscopy technique can do the quantification of protein content in milk powder fast and non-destructively and the process was simple and easy to operate. The results of this study can be used for the design of a simple and non-destructive spectra sensor for the quantitative of protein content in milk powder.
2008 Vol. 28 (05): 1071-1075 [Abstract] ( 811 ) PDF (1046 KB)  ( 614 )
1076 Using Fourier Transform to Analyse Differential Optical Absorption Spectrum
LIU Qian-lin1,WANG Li-shi2*,HUANG Xin-jian2
DOI: 10.3964/j.issn.1000-0593.2008.05.027
According to the theory of differential optical absorption spectral technique, the differential optical absorption spectral monitoring equipment was designed. Aiming at two kinds of main pollutants, SO2 and NO2, in the atmosphere, this technique was used to monitor them. The present article puts forward the signal analysis method of Fourier transformation to process the above-mentioned two kinds of absorption spectra. The two approaches contain the removeal of noise and the fitting of the slow variety. On the frequency chart after the spectrum was transformed, the low frequency corresponded to the slow variety part and the high frequency corresponded to the noise part of the original spectrum, so through intercepting a certain frequency segment and using inverse Fourier transformation the slow variety part of the low frequency and the noise part of the high frequency of the absorption spectrum could be subtracted. After farther processing we can get a higher resolution differential absorption spectrum of the gas. According to the strength of the spectrum, we can calculate the concentration of the gas. After analysis and comparison with the conventional method, it is considered a new processing method of differential optical absorption spectral technique, and the method can fit the slow variety much better.
2008 Vol. 28 (05): 1076-1079 [Abstract] ( 540 ) PDF (1075 KB)  ( 577 )
1080 Development of Aperture Probe Near-Field Raman Spectroscopy and Microscopy
JIANG Yang,REN Bin,TIAN Zhong-qun*
DOI: 10.3964/j.issn.1000-0593.2008.05.039
The appearance of near-field Raman spectroscopy that is based on aperture probe scanning near-field optical microscopy makes the resolution of Raman spectroscopy beyond the optical diffraction limitation. It provided a powerful tool to probe chemical information of sample on subwavelength scale. The present article illustrates the influence of probe character on near-field Raman spectroscopy. Furthermore, the development over ten years in chemical resolution imaging on nanoscale, special properties of liquid-liquid interface, exploring SERS mechanism and observing hotspots beneath subwavelength scale etc. were introduced in detail.
2008 Vol. 28 (05): 1080-1090 [Abstract] ( 1306 ) PDF (2324 KB)  ( 452 )
1091 Study on Raman Linear Model of Human Breast Tissue
YU Ge1,Lü Ai-jun1,WANG Bin2,TAN En-zhong1,GAO De-wen1
DOI: 10.3964/j.issn.1000-0593.2008.05.050
A linear regression model for Raman spectra of human breast tissue was developed with 10 basis spectra which were derived from the spectra of fat, cell cytoplasm, collagen, β-carotene, DNA and cholesterol etc. This model was tested statistically with more than 2 000 spectra collected from both normal and tumor breast tissue samples. The confidence of F-test for the model significance was 1 to all the spectra and the average of multiple determination coefficients measuring the fit goodness was 0.95. The normalized fit coefficients reflected, to a certain extent, the relative quantities of the Raman-active components in tissue represented by the basis spectra. In comparison with normal breast tissue, the coefficients of the cell cytoplasm and DNA basis spectra increased apparently for the tumor one, and the coefficient of fat basis spectrum changed reversely, which was easily understood with the known pathological changes in the tissue. Mapping spectra were also fitted with this model. This work is helpful to understanding the biochemical/morphological changes in the breast tumor tissues and to developing the Raman diagnostic method for breast tumor.
2008 Vol. 28 (05): 1091-1094 [Abstract] ( 1207 ) PDF (1238 KB)  ( 509 )
1095 Near Infrared Raman Spectra Analysis of Rhizoma Dioscoreae
LIN Wen-shuo,CHEN Rong*,LI Yong-zeng,FENG Shang-yuan,HUANG Zu-fang,XIE Bing-xian
DOI: 10.3964/j.issn.1000-0593.2008.05.026
A novel and compact near-infrared (NIR) Raman system was developed using 785 nm diode laser, volume-phase technology holographic system, and NIR intensified charge-coupled device (CCD). The Raman spectra and first derivative spectra of rhizoma dioscoreae were obtained. The Raman spectra of rhizoma dioscoreae showed three strong characteristic peaks at 477, 863 and 936 cm-1, respectively. The major ingredients are protein, amino acid, starch, polysaccharides and so on, matching the known basic biochemical composition of rhizoma dioscoreae. In the first derivative spectra of rhizoma dioscoreae, the distinguishing characteristic peaks appeared at 467,484,870 and 943 cm-1. Contrasted with rhizoma dioscoreae Raman spectra in the ranges of 600 to 800 cm-1 and 1 000 to 1 400 cm-1, the changes in rhizoma dioscoreae Raman first derivative spectra are represented more clearly than the rhizoma dioscoreae Raman spectra. So the rhizoma dioscoreae Raman first derivative spectra can be an accurate supplementary analysis method to the rhizoma dioscoreae Raman spectra.
2008 Vol. 28 (05): 1095-1097 [Abstract] ( 1163 ) PDF (468 KB)  ( 539 )
1098 Wavebands Selection for Rice Information Extraction Based on Spectral Bands Inter-Correlation
WANG Fu-min,HUANG Jing-feng,XU Jun-feng*,WANG Xiu-zhen
DOI: 10.3964/j.issn.1000-0593.2008.05.049
The hyperspectral remote sensing data usually involve hundreds or even thousands of narrow bands, which may be crucial for providing additional information with significant improvements over broad bands in quantifying biophysical and biochemical variables of agricultural crop. However, the huge data generated by hyperspectral systems, and the problems this presents for storage and analysis, have far prevented the routine use of such data. The objective of the present research was to identify the spectral bands in the visible and near-infrared range that were suitable for the study of rice. The hyperspectral reflectance of canopy in different development stages was measured in experimental field using a 1 nm-wide spectroradiometer but was aggregated to 10 nm-wide bandwidths to match the first spaceborne hyperspectral sensor, Hyperion. The correlation coefficients(r) between all the combinations of spectral bands were computed, and then they were converted to R2, which constituted R2 matrices. The matrices were plotted against wavebands. The criterion of band selection is that the lower the R2 value, the less the redundancy between two wavebands while the higher R2 indicates that there is redundant information between two wavebands. According to the criterion, the wavebands corresponding to the first 100 minimum R2 values were selected from all canopy spectra collected on different dates. And then these bands were analyzed. The results indicate that the visible and infrared (NIR and SWIR) themselves contain redundant information. The wavebands containing abundant information of rice are located in specific bands in the longer wavelength portion of the visible region, with secondary clusters in red edge region, in strongly reflective near-infrared region with relatively higher reflectance, in one particular section of short wave near-infrared (SWIR) (1 530 nm) and in the second maximum reflectance region of SWIR (2 215 nm). Compared with the selected bands with other vegetation, rice seems to have three spectral regions of 400-410 nm, 630-650 nm and 1 520-1 540 nm, which exclusively depict the characteristics of rice. Moreover, this research identified 17 spectral bands in the visible and near-infrared region, which were 405, 565, 585, 605, 620, 640, 660, 680, 695, 705, 720, 740, 865, 910, 1 085, 1 530 and 2 215 nm. These bands contain the majority of the rice information content. A reduction in band number without significant information loss is important because it makes it possible to achieve fine spatial resolution without sacrificing the ability to characterize rice status.
2008 Vol. 28 (05): 1098-1101 [Abstract] ( 770 ) PDF (522 KB)  ( 557 )
1102 Identification Methods of Crop and Weeds Based on Vis/NIR Spectroscopy and RBF-NN Model
ZHU Deng-sheng1,PAN Jia-zhi2,HE Yong2*
DOI: 10.3964/j.issn.1000-0593.2008.05.023
The automated recognition of crop and weed by using Vis/NIR spectral in field is one of hottest research branches of agriculture engineering. If the recognition is efficient and effective, then the variate operations of herbicide or fertilizer spraying in field could be realized. Many researches have pointed out that the reflectance rate of green plant leaves could be used to identify the varieties. As the colors and surface textures of crop and weed were change in different living phases,these changes may exert great influence on the reflectance spectral of plant leaves. Vis/NIR spectra of three weeds and one crop in two different terms were recorded by spectral meter ASD FieldSpec Pro FR. Its wave band is from 325 to 1 075 nm. The scan time was 270 ms. The scanning times of per sample was set to 30 times. Firstly, 23 days after the planting of soybean, some soybean leaves and weeds leave were picked from the field, and brought to lab to record spectral. The lighting condition was controlled by an artificial halogen bulb. Secondly, on the 45th day, the same experiment was done. The three weeds were goosegrass, alligator alternanthera and emarginate amaranth. The crop was soybean seedling. Totally 378 samples were drawn for two terms. As one original reflectance spectrum contains 651 float numbers, the total data volume was huge. Using wavelet transform to compress data volume and extract characteristic spectral data was tried. The result was 114 float numbers per sample. Among them, 250 samples from two terms were used as input data to build artificial neural network model, and those left were used to check the validation. Radial basis function neural network model is widely used in pattern recognition problems. It is a nonlinear and self adaptive parallel. By assigning a 1 by 4 vector to each spectral samples, the source data could be used to build an RBF-NN model. All the samples were assigned these standard output data. Then, the left 128 samples were used to check the performance of the model. The result is that only 3 samples from the second term of goose grass were wrongly classified as alligator alternanthera, which showed that RBF neural network have strong ability to differentiate spectra of species of plant, and that there was no massive difference of NIR spectra of one plant in different life periods. This demonstrated that the NIR spectra could be used to identify crop from weed with no need to care about the living stages of these plants.
2008 Vol. 28 (05): 1102-1106 [Abstract] ( 1959 ) PDF (1020 KB)  ( 477 )
1107 Effect of Acidity on the Interaction of Oflxacin and Bovine Serum Albumin
TANG Zhen-qiang1,HE Gan-wu2,YI Ping-gui1*
DOI: 10.3964/j.issn.1000-0593.2008.05.048
Bovine serum albumin (BSA) exists as N(pH -7.0), B(pH -9.0), and E (pH<3.5)= isomeric forms in the solution of different pH. Acid effect on the structure of bovine serum albumin and the interaction of different structure of BSA with Oflxacin were studied by UV-Vis and fluorescence spectroscopy. Based on the fluorescence quenching of bovine serum albumin and Frster energy transfer mechanism, the quenching constants, energy transfer efficiencies and the binding distances were determined at four different pHs. The results showed that Oflxacin has the ability to quench bovine serum albumin fluorescence with the optimal condition of fluorescence quenching constants of 1.928 1×105 L·mo·l-1, binding distance of r=2.55 nm and quenching efficiency of 8.63×104 L·mo·l-1 at pH 4.9. Non-radiative energy transfer and static quenching were the cause of fluorescence quenching. The influence on the binding of Oflxacin and bovine serum albumin under neutral, subacidity and alkalescent conditions was not obviously observed, and the electrostatic interaction was not the main force. The effect of Oflx on the conformation of BSA was also investigated using synchronous fluorescence spectrometry.
2008 Vol. 28 (05): 1107-1110 [Abstract] ( 565 ) PDF (1008 KB)  ( 489 )
1111 Study of Inversion and Classification of Particle Size Distribution under Dependent Model Algorithm
SUN Xiao-gang,TANG Hong,YUAN Gui-bin
DOI: 10.3964/j.issn.1000-0593.2008.05.024
For the total light scattering particle sizing technique, an inversion and classification method was proposed with the dependent model algorithm. The measured particle system was inversed simultaneously by different particle distribution functions whose mathematic model was known in advance, and then classified according to the inversion errors. The simulation experiments illustrated that it is feasible to use the inversion errors to determine the particle size distribution. The particle size distribution function was obtained accurately at only three wavelengths in the visible light range with the genetic algorithm, and the inversion results were steady and reliable, which decreased the number of multi wavelengths to the greatest extent and increased the selectivity of light source. The single peak distribution inversion error was less than 5% and the bimodal distribution inversion error was less than 10% when 5% stochastic noise was put in the transmission extinction measurement values at two wavelengths. The running time of this method was less than 2 s. The method has advantages of simplicity, rapidity, and suitability for on-line particle size measurement.
2008 Vol. 28 (05): 1111-1114 [Abstract] ( 1982 ) PDF (698 KB)  ( 503 )
1115 Spectral Changes of C-Phycocyanin with Different Molar Ratios of SPDP
YAN Shi-gan1,3,CHEN Xiu-lan1,ZHANG Xi-ying1,ZHOU Bai-cheng1,2,ZHANG Yu-zhong1*
DOI: 10.3964/j.issn.1000-0593.2008.05.005
Pure C-phycocyanin was prepared from Spirulina platensis using one-step anion-exchange chromatography. The C-PC obtained was with an absorption maximum at 620 nm and a fluorescence emission maximum at 640 nm when excited by 580 nm. SPDP is an excellent heterobifunctional crosslinker for thiolating amines. Different molar ratios of SPDP have remarkable influence on the absorption and fluorescence spectra of C-phycocyanin. The absorption maximum and fluorescence emission maximum both decreased and blue-shifted from 640 nm to 630 nm as the molar ratios of SPDP increased. It was found that the molar ratios of SPDP to C-phycocyanin was not more than 100 was appropriate to being conjugated with other biomolecules from the absorption and fluorescence spectra of C-phycocyanin.
2008 Vol. 28 (05): 1115-1117 [Abstract] ( 2784 ) PDF (574 KB)  ( 550 )
1118 Synthesis of a Novel Calix[4]arene Derivative with 2-Methylquinoline and Study of It’s Spectrum Character with Zn(Ⅱ) and Cu(Ⅱ)
LIU Shi-zhu,TANG You-wen*
DOI: 10.3964/j.issn.1000-0593.2008.05.012
A novel calix[4]arene derivative(25,27-two2-methylquinoline t-butylcalix[4]arene, MQBC) with the lower rim modified fluorescence groups was synthesized. IR spectra, elemental analysis, HNMR spectra and MS were used to determine its structure. Meanwhile, the spectra characters of MQBC and the fluorescent behaviors of the complex with zinc(Ⅱ) and copper(Ⅱ) were investigated, and the results showed that the lower rim oxygen atoms in calix[4]arenes may act as electrons donor to metal ions. Calix[4]arene was chosen as a basic skeleton of a photoresponsive ion carrier because its quinolin derivatives are known to emit fluorescence and absorb UV in the solution, and the information of the complex with metal ions will be known by spectra experiment. The UV absorbance became weak at the band of 226 nm but was enhanced at the band of 315 nm when it bound zinc ions, The complex constant(K) and binding ratio(x) were determined to be 2 064 L·mol-1 and 1, respectively, by UV spectra experiment. It is expected that MQBC will be applied to the detection of trace zinc ions. The fluorecence spectra experiment found that MQBC is has feeble fluorecence attributed to the intramolecular photoinduced electron transfer(PET) between oxygen atoms and methylquinoline groups. When MQBC was combined with zinc(Ⅱ) and copper(Ⅱ), it caused the inhibiting photoinduced electron transfer process between oxygen atoms and methylquinoline groups leading to the enhancement of fluorescence. In addition, the photoinduced electron mechanism was discussed and the influence of the concentration of zinc(Ⅱ) and copper(Ⅱ) on the fluorescence intensities was studied.
2008 Vol. 28 (05): 1118-1121 [Abstract] ( 1390 ) PDF (1039 KB)  ( 438 )
1122 Preparation of TiO2 Pillared Montmorillonite Photocatalyst and Its Photocatalytic Activity to Degradation Reaction of Acidic Fuchsine by Sunlight
YANG Wu,CHENG Li-yan,XUE Zai-lan,GUO Hao,GAO Jin-zhang
DOI: 10.3964/j.issn.1000-0593.2008.05.013
TiO2 pillared montmorillonite composite photocatalyst was synthesized by acid-catalyzed sol method and characterized by IR, UV-Vis, TG/DTA, XRD, SEM etc. Spectral analyses have demonstrated that TiO2 pillared montmorillonite(Ti-MMT) has wider interlayer distance than Na substituted montmorillonite(Na-MMT) and higher optical absorption efficiency than nanoscale anatase TiO2. The photocatalytic degradation reaction of acidic fuchsine by sunlight was employed to evaluate the catalytic activity of the composite catalyst. It was found that, besides easy reclaimation, the photocatalytic activity of the catalyst was much higher than that of the pure nanosized anatase TiO2. When the addition amount of Ti-MMT is 0.2 g·(100 mL)-1 and pH of acidic fuchsine solution is 3, the dye could be degraded thoroughly in 40 min and the degradation reaction obeys Langmuir- Hinshelwood equation.
2008 Vol. 28 (05): 1122-1125 [Abstract] ( 1373 ) PDF (1533 KB)  ( 505 )
1126 A Novel Analyzing Method for the Signal Denoising of DNA Sequencing
ZHENG Hua1,2,WANG Li-qiang1,SHI Yan1,WANG Jie1,LU Zu-kang1
DOI: 10.3964/j.issn.1000-0593.2008.05.016
Fluorescence signals in DNA sequencing are often contaminated by noise, which has negative influence on the accuracy and detection limit of analysis. Wavelet analysis has excellent time and frequency domain resolution for signal denoising compared to other conventional filtering methods. Before the signal denoising process, a key problem is how to choose a suitable wavelet base, decomposition level and denoising threshold, which have great influence on the quality of signal denoising. In order to construct the same noise model as that in experiment and evaluate the denoising algorithm precisely, a novel method is presented: the real noise signal acquired from the experimental system was added to an ideal signal to simulate a noisy DNA sequencing signal, thus the denoising efficiency could be evaluated accurately. The denoising results indicate that using sym 7 wavelet base, decomposition level at 5 and using fixed form soft threshold can effectively reduce the noise. After being processed, the SNR was improved more than 5 times. When the same algorithm was applied to the experimental DNA sequencing data, the results were more credible than those obtained through other algorithms based on the random noise model.
2008 Vol. 28 (05): 1126-1129 [Abstract] ( 1193 ) PDF (891 KB)  ( 525 )
1130 Three Dimensional Fluorescence Excitation-Emission Matrix Spectrum of Dissolved Organic Substance in Marine Microalgaes Growth Process
REN Bao-wei1,2,ZHAO Wei-hong1*,WANG Jiang-tao3,WANG Lu4
DOI: 10.3964/j.issn.1000-0593.2008.05.017
海洋微藻;溶解有机物;三维荧光光谱;类蛋白荧光;类腐殖质荧光
2008 Vol. 28 (05): 1130-1134 [Abstract] ( 238 ) PDF (1726 KB)  ( 545 )
1135 Study on the Interaction of Luteolin with Human Serum Albumin by Fluorescence Quenching Method
ZHANG Zhi-heng1,LI Cai-rui2,MA Jing-jun1,WU Qiu-hua1,WANG Chun1,WU Qian1,WANG Zhi1*
DOI: 10.3964/j.issn.1000-0593.2008.05.014
The interaction between luteolin and human serum albumin (HSA) was studied by using fluorescence quenching spectra, synchronous fluorescence spectra and ultra-violet spectra. The results showed that luteolin had a strong ability to quench the fluorescence of HAS. The Stern-Volmer curve of the fluorescence quenching of HSA by luteolin indicated that the mechanism behind the quenching between luteolin and HSA was a static quenching. According to the Fōrster theory of non-radiation energy transfer, the binding distances (r) and the binding constants (KA) were calculated. The thermodynamic parameters showed that the interaction between luteolin and HSA was driven mainly by hydrophobic force. Synchronous spectra were used to investigate the conformational changes of HSA.
2008 Vol. 28 (05): 1135-1139 [Abstract] ( 2280 ) PDF (1112 KB)  ( 607 )
1140 Preparation and Structural Characterization of mixed LB Films of TMB·TCNQ and Stearic Acid
WANG Yi-bing,WU Wei-hong,LU Fei,WANG Hai-shui*,XI Shi-quan
DOI: 10.3964/j.issn.1000-0593.2008.05.036
Mixed LB films of the CT complex of TMB·TCNQ and stearic acid (SA) were prepared. The structures, molecular orientation and morphology of the mixed LB films were characterized by IR, UV-Vis-NIR, XRD and AFM. Our results show that TMB·TCNQ could be deposited on solid substrates by mixing with SA. The complex is mixed-stack, and the degree of charge transfer is 0.35. The chromophore planes of both TCNQ and TMB are perpendicular to the substrate surface and the hydrocarbon chain of SA is inclined at an angle with respect to the substrate surface. There are two kinds of diffraction bands in the XRD spectra, and they probably arise from SA and TMB·TCNQ, respectively. The morphology of mono- and multilayer mixed LB films with molar ratio 1∶1 consists of many nanorods and particles, and the amount of nanorods and particles increase with increasing the number of monolayers.
2008 Vol. 28 (05): 1140-1144 [Abstract] ( 176 ) PDF (1088 KB)  ( 509 )
1145 Immunoresonance Scautering Spectral Assay for the Determination of Antithrombin-Ⅲ
JIANG Bo1,2,JIANG Zhi-liang1*
DOI: 10.3964/j.issn.1000-0593.2008.05.055
A new sensitive, selective and simple immune resonance scattering spectral assay was proposed for the determination of trace amounts of Antithrombin-Ⅲ(AT-Ⅲ). It was based on the immune reaction of AT-Ⅲ with the goat-anti-human AT-Ⅲ antibody and the resonance scattering effect of the immunocomplex particles in pH 7.2 Tris-HCl buffer solution and in the presence of polyethelene glycol (PEG)6000. The results showed that the resonance scattering signal of AT-Ⅲ and goat-anti-human AT-Ⅲ antibody was very weak. However, AT-Ⅲ was combined with goat-anti-human AT-Ⅲ antibody specifically, and aggregated to form immunocomplex particles, which enhanced the resonance scattering intensity greatly and produced three resonance scattering peaks at 368 nm, 491 nm and 536 nm respectively. The strongest resonance scattering peak was at 491 nm. In the present paper, the influences of pH, goat-anti-human AT-Ⅲ antibody and PEG-6000 concentration, incubation temperature, reactive time, and foreign substances were investigated. The result showed that the resonance scattering intensity at 491 nm (IRS) is linear to the AT-Ⅲ concentration in the range of 62.5 to 850 ng · mL-1, under the optimum conditions of 0.30 mL goat-anti-human AT-Ⅲ antibody, 30 mg·mL-1 polyethelene glycol-6000, being incubated at 37 ℃ for 15 min, the voltage at 400 V, and the excitation and emission slit width both at 5.0 nm. Its regress equation is ΔIRS=0.062 5c+1.36,and a relative coefficient of 0.996, with a detection limit of 29.4 ng·mL-1. The results of co-existing substance tolerance test showed that 1.40×105 ng·mL-1 glycine, 9.0×103 ng·mL-1 L-glutamic acid, 5.0×105 ng·mL-1 glucose, 5.0×104 ng · mL-1 urea, 1.5×104 ng·mL-1 IgG, 3.0×104 ng·mL-1 human serum albumin, and 1.5×104 ng·mL-1 bovine serum albumin did not interfere with the resonance scattering determination of 2.50×102 ng·mL-1 AT-Ⅲ, when the relative error was within ±10%. Four polyethelene glycols, i.e. polyethelene glycol-4000, polyethelene glycol-6000, polyethelene glycol-10000 and polyethelene glycol-20000, on the immune resonance scattering spectral system were examined in details. The results show that polyethelene glycol-6000 has low blank and high ΔIRS value, and was chosen for use. The new resonance scattering spectral method features high sensitivity, good selectivity, simplicity and rapidity, and was applied to the quantitative analysis of AT-Ⅲ in plasma and serum samples with satisfactory results. Its recovery is in the range of 90.2%-108.9%.
2008 Vol. 28 (05): 1145-1148 [Abstract] ( 168 ) PDF (610 KB)  ( 438 )
1149 Study and Application of Determination of Protein with Meso-Tetra-(3,5-Dibromo-4-Hydroxyphenyl) Porphyrin Fading Spectrophotometry
YAN Mei,CHEN Xin,ZHANG Li-na,MA Hong-min,SUN Shu-ting,WEI Qin*
DOI: 10.3964/j.issn.1000-0593.2008.05.019
In the present paper, the binding characteristics and spectral behavior of interaction of meso-tetra-(3,5-dibromo-4-hydroxyphenyl) porphyrin [T(DBHP)P] as a new-style probe with protein were studied by the techniques of spectrophotometry. The experiment showed that Tween-80 microemulsion was efficiently used to enhance the sensibility and stability of the system at pH 4.17(Britton-Robinson buffer solution). Under optimum conditions, the characteristics of absorption spectral of meso-tetra-(3,5-dibromo-4-hydroxyphenyl) porphyrin-protein were investigated, the maximum absorption was located at 425 nm, and the reducing value of absorbance A was in proportion to the concentration of proteins in the range 0.50-6.00 μg·mL-1 for bovine serum albumin, 0.05-0.60 μg·mL-1 for ovalbumin, and the limits of detection were 0.106 μg·mL-1 for bovine serum albumin and 0.039 μg·mL-1 for ovalbumin. The experiments indicated that the proposed method featwed high sensitivity and good selectivity and stability, and was simple and relatively free from interference of coexistent substances. It has been applied to the determination of protein in milk samples with satisfactory. The recovery for the investigated protein from milk was 99.56%-100.2% and the relative standard deviations were less than 2.2%. The sensitive method for the quantitative determination of proteins was proposed and may be applicable to the determination of ultra amounts of protein in food analysis. The effect of ionic strength on the system was investigated, and the result indicated that the binding force between meso-tetra-(3,5-dibromo-4-hydroxyphenyl) porphyrin and protein was judged as electrostatic force. The influence of protein denaturation was also studied, under higher temperature the structure of protein was destroyed, and thermodynamic movement of the molecular of protein was intensified as the heating time extended.
2008 Vol. 28 (05): 1149-1152 [Abstract] ( 2659 ) PDF (614 KB)  ( 498 )
1153 Comparison of 51 Element Contents in Normal Human Lung Tissue over Twenty Years
ZENG Jing1,2,OUYANG Li1,2,WANG Xiao-yan1,2,LIU Ya-qiong2,XIE Qing2,CHU Hong-da3,WU Quan3,FAN Ti-qiang3,WANG Jing-yu1,2*
DOI: 10.3964/j.issn.1000-0593.2008.05.006
Changes in content and distribution of elements in human tissues may reflect changes in environmental backgrounds, and are closely related to human health. To investigate the change in element background in normal lung tissue in different stage, we used ICP-MS, ICP-AES and GFAAS to determine 51 element contents in normal human lung samples of 1982-83 year (n=7) and compare with those of 2004-05 year (n=16). Samples were from healthy male adults who died suddenly, and were treated with microwave digestion and wet digestion method. The results show that the contents of 23 elements (Na, Mg, P, K, As, Mo, Ag, Ba, Bi, Y, La, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu) are significantly higher, and 6 elements (Zn, Ga, Ge, Se, Au and Zr) are significantly lower in the 2004-05 samples than those in the 1982-83 samples. This difference would be related to the changes in environmental backgrounds and people’s living habit during twenty years. The distinctive decrease in contents of the 2004-05 samples for most measured rare earth elements (REEs) may be due to more rational usage of REEs in present, while were the soil and corps were largely abused in 1980s in China. The significant increase in contents of some useful micro-elements (Zn and Se ) in the present samples maybe because of the increased intake of these elements as people own more health consciousness. Besides, the increased contents of heavy metal Pb, Cd, Cr and Ni in the present samples may be related to the deterioration of air quality as industrialization course. More than half of measured elements have been significantly changed over twenty years, indicating that some normal value ranges of element contents should be adjusted according to the difference.
2008 Vol. 28 (05): 1153-1156 [Abstract] ( 797 ) PDF (400 KB)  ( 448 )
1157 Simultaneous Determination of Trace Elements in Mistletoe by ICP-AES
LI Ti1,NI Yong-nian2,GUO Lan1,LI Li1
DOI: 10.3964/j.issn.1000-0593.2008.05.022
A method for the simultaneous determination of elements Cu,Mg,Zn,Mn,Ni,Se,K,Na,Ca and Fe in mistletoe after HNO3-H2O2 digestion by ICP-AES was studied. The recoveries obtained by standard addition method were between 90.8% and 112.8%, while the RSD (n=5) was in the range of 0.47%-4.59%. The results showed that there were rich K, Ca, Mg and Na in the mistletoe, and offered scientific data for the ulterior study on mistletoe.
2008 Vol. 28 (05): 1157-1159 [Abstract] ( 1878 ) PDF (486 KB)  ( 494 )
1160 Estimation of Soil Organic Matter and Soil Total Nitrogen Based on NIR Spectroscopy and BP Neural Network
ZHENG Li-hua,LI Min-zan*,PAN Luan,SUN Jian-ying,TANG Ning
DOI: 10.3964/j.issn.1000-0593.2008.05.020
Estimation models of soil organic matter (SOM) and soil total nitrogen (TN) were established based on NIR spectroscopy and BP neural network. A total of 150 soil samples were collected from the tested farm, and the NIR spectra of all soil samples were measured. First, data pretreatment was performed for each sample with the method of locally weighted scatter plot smooth filtering. Then the box plot analysis for the measured SOM data and TN data were conducted separately and the information about the shape, location, and distribution of the target data was obtained. The variance between the SOM data was very small, and most of them were concentrated on the median. This was also observed from TN data. Thus clustering analysis was carried out for the target parameters of the soil samples so that the original dataset with 150 spectra was clustered to 50 groups. For each group, the average of spectral data was calculated at every wavelength to obtain a new spectrum. The new spectrum was calculated with natural logarithm and normalized, which was taken as a new sample. Principal component analysis (PCA) was executed for 50 new samples and the principal components with over 99.98% of cumulative proportion of correlation matrix were extracted to establish BP neural network. According to the analysis result of SOM content, the calibration accuracy of the model was 0.999, and the validation accuracy reached to 0.854. According to the analysis result of the soil TN content, the calibration accuracy of the model was close to 1, and the validation accuracy reached 0.808. The result shows that the smooth filter can weaken the noise in the data, expose the data features, provide a reasonable starting approach for parametric fitting; and improve the prediction accuracy; It is feasible and practical to estimate soil parameters by using BP neural network with the prediction accuracy of 0.854 (SOM) and 0.808 (TN); Compared to the other prediction modeling method, the BP neural network model has higher robustness and better fault tolerance, and the model accuracy would not be affected by the several outline samples when the number of samples is large enough.
2008 Vol. 28 (05): 1160-1164 [Abstract] ( 2732 ) PDF (1164 KB)  ( 510 )
1165 Determination of Trace Elements in Traditional Chinese Medicine from Changbai Mountain by ICP-MS
YAO Yan-hong1,XU Gui-hua2,ZHANG Jing-dong1,LI Cheng-fan1,LI Dong-hao1
DOI: 10.3964/j.issn.1000-0593.2008.05.010
The effects of different digestives for the fritillaria and atractylodes were compared. Many trace elements in the planted and wild fritillaria and atractylodes were determined by ICP-MS. The results show that the RSD and recovery are better if the planted and wild fritillaria and atractylodes were digested with HNO3-H2O2. Among the many elements determined from the fritillaria and atractylodes, Cu, Zn, Fe, Mg and Mn are the dominant chemicals. The content of Fe was higher in the wild fritillaria and atractylodes than that in the planted fritillaria and atractylodes, while the contents of heavy metal Pb and Cd were lower in the wild fritillaria and atractylodes than those in the planted fritillaria and atractylodes. The wild fritillaria and atractylodes contain Co,which was not determined in the planted fritillaria and atractylodes. The experimental results showed that the detection limits were lower than 0.086 ng·g-1 with low RSD(n=7, 4.85%)for most metal chemicals determined, and the standard recoveries (n=7) ranged from 96.8 to 103.4%.
2008 Vol. 28 (05): 1165-1167 [Abstract] ( 2320 ) PDF (371 KB)  ( 562 )
1168 Determination of Mineral Elements in Different Part of Astragalus Membranaceus(Fisch.) by FAAS
WANG Wei-ling1,LIANG Zong-suo1,2*,TAN Yong2,DUAN Qi-mei1
DOI: 10.3964/j.issn.1000-0593.2008.05.007
Having digested the root and shoot of Astragalus membranaceus (Fisch.) with the mixture of nitric acid and perchloride acid (4∶1) under the condition of the bolling point and the normal pressure, the contents of the five mineral elements necessary to humanity, potassium, copper, zinc, iron and manganese in root and shoot of Astragalus membranaceus (Fisch.) were determined by flame atomic absorption spectroscopy (FAAS), and the results were analyzed in statistics. The correlative coefficient of the standard curve in this method is 0.997 3-0.999 9, the recovery of standard addition was 92.88%-109.25% and the relative standard deviation (RSD, n= 5) was 0.393 5%-3.175 2%. The method is simple and the results were accurate and reliable. The contents of K, Fe, Zn, Mn, Cu in the root and shoot of Astragalus membranaceus (Fisch.) were compared. The results showed that the sequence of the content of metal elements is as follows in all samples: K>Fe>Zn>Mn>Cu. However, the distribution of elements in shoot and root is not uniform, and the content of Fe, Zn and Cu in root is richer than in shoot. There are abundant Fe, Zn and Cu in root, for example, the content of Fe in root is 1.54 times that in shoot. In addition, there are also abundant mineral elements in the shoot, especially in K and Mn, for example, the content of K in shoot is 1.63 times that in root. The contents of K, Fe, Zn, Mn and Cu in shoot are in agreement with the medical effects of Astragalus membranaceus (Fisch.). The results should provide useful data for investigating the distribution of mineral element in Astragalus membranaceu body and the correlation between the mineral element content and the effect of medicine in Astragalus membranaceus (Fisch.).
2008 Vol. 28 (05): 1168-1171 [Abstract] ( 1826 ) PDF (542 KB)  ( 564 )
1172 Determination of Trace Elements of Gentiana Macrophlla and Gentiana Straminea by Microwave Digestion-FAAS
ZHOU Yu-shan1,ZHANG Xi-ling1,WANG Rong-bin1,XIA Qi2,AN Xia2
DOI: 10.3964/j.issn.1000-0593.2008.05.021
An acid-assisted microwave digestion procedure is optimized for the determination of trace elements in traditional Chinese medicine by the use of flame atomic absorption spectrometric (FAAS) techniques. Microwave-assisted digestion has the advantages of reduced time for sample dissolution, fewer possibilities for technical errors caused by spilling of hot digestion solutions, use of less chemicals, and lower losses of volatile metals. In addition, modern microwave ovens are safer and simpler and provide more controlled and reproducible conditions than hot plate or block digesters. Flame atomic absorption spectrometry(FAAS) is more commonly applied techniques in the determination of trace elements. The accurate measurement of trace elements concentrations in samples of traditional Chinese medicine is an important goal in research for medical effects of traditional Chinese medicine. The purpose of this study was to determine the contents of the trace elements in Gentiana macrophlla and Gentiana straminea. In order to identify the accuracy of the procedure, the operating conditions was selected before the determination of trace elements. In order to gauge the effectiveness of digestion, the selection of digestion conditions of the technique was undertaken. The results showed HNO3-H2O2 (5∶1) as a microwave digestion agent with suitable temperature and time was optimum choice in the digestion procedure. Analysis limits were also selected according to the low detection limits and the good precision. They were Fe(248.3 nm), Mn(279.5 nm), Ni(232.0 nm), Cu(324.8 nm), Zn(2.139 nm), Ca(422.7 nm), Mg(285.2 nm) and Cr(357.9 nm), respectively. The working curves were obtained by using multi-elemental standard solutions and line relation was good. Under the selected conditions, the contents of trace elements Fe, Mn, Ni, Cu, Zn, Ca, Mg and Cr in Gentiana macrophlla and Gentiana straminea were directly determined using working curve methods. The relative standard deviations (RSD) and recovery of the method have been undertaken to obtain reliable results for trace element determinations. The recovery rates obtained by standard addition method were between 88.1%-114.5%, and the relative standard deviations (RSD) were lower than 3.12% after optimization of the operating conditions. These figures showed that the method gave good recoveries and accuracy. The analytical results indicated that there were comparatively rich elements in Gentiana macrophlla and Gentiana straminea, such as Ca, Mg, Fe, Mn and Zn, especially the concentration of Ca and Mg. However, concentrations of Ni and Cr in Gentiana macrophlla and Gentiana straminea were very low, especially the concentration of Ni. The worse value obtained for Ni was probably due to its inhomogeneous distribution and very low concentration in Gentiana macrophlla and Gentiana straminea. In addition, a comparison of the contents of trace elements between Gentiana macrophlla and Gentiana straminea indicated that Gentiana macrophlla was rich in the trace elements such as Fe, Mn, Ni and Mg, and Gentiana straminea was rich in the trace elements such as Zn, Cu, Ca and Cr. The result will provide scientific datas for discussing the relationship between the contents of these elements in Gentiana macrophlla and Gentiana straminea and the medical effects. Furthermore,our study provides new scientific foundation for further study and general application of Gentiana macrophlla and Gentiana straminea.
2008 Vol. 28 (05): 1172-1175 [Abstract] ( 616 ) PDF (453 KB)  ( 545 )
1176 Recent Development of Speciation Analysis for Trace Arsenic
ZHU Zhi-liang,QIN Qin
DOI: 10.3964/j.issn.1000-0593.2008.05.018
The present paper summarizes recent development in the measurements of trace arsenic element, including six aspects such as spectrophotometry, atomic adsorption spectrometry, hydride generation atomic fluorescence spectrometry, inductively coupled plasma-atomic emission spectroscopy, X-ray fluorescence spectrometry,united detection of chromatography-atomic characteristic and so on. The basic characteristics and application fields of each method are introduced. The advantages and disadvantages of different methods are discussed. It is pointed out that great progress has been made for the measurements of trace arsenic element in the past decades, but studies on speciation analysis of trace arsenic are still limited. For various speciation of trace arsenic in nature, how to find and develop various efficient,selective separation and analysis technologies is one of the most important problems to be considered. More attention should be paid to the united application of different modern analysis technologies for trace arsenic.
2008 Vol. 28 (05): 1176-1180 [Abstract] ( 1639 ) PDF (691 KB)  ( 442 )
1181 Study on the Cultural Relic Material Site and Period by EDXRF
ZHOU Shao-hua1*,FU Lue1,LEUNG Bao-liu2
DOI: 10.3964/j.issn.1000-0593.2008.05.028
With the development of the element analysis technology, the energy-dispersive X-ray fluorescence (EDXRF) technique is now well established as a powerful tool for qualitative and quantitative elements analyses when studying on the cultural relic materials. Being characteristic of quick and non-destructive analysis, involving high-precision, a wide concentration range, easy sample preparation, good reproducibility and synchronously analyzing the elements from Na(Z11) to U(Z92), this technique is appropriate for analyzing precious ancient ceramics. In the present study, the major, minor and trace elements compositions of 6 samples from Guan kiln in the southern song dynasty, 6 samples from Longquan kiln in the Southern Song dynasty and 2 modern imitations were analyzed by EDXRF. The results prove further that the raw materials in Hangzhou and Longquan are different and stable, and show that EDXRF is a successful and feasible method for identifying the provenance and dynasty an ancient ceramic originated from.
2008 Vol. 28 (05): 1181-1185 [Abstract] ( 2408 ) PDF (11939 KB)  ( 485 )
1186 A Study on Image Processing of Digital Radiography and Measure of Material Micro-Density Directly
XIA Ping1,XU Guang-ming2,YIN Song1, LIU Sheng-quan1*,XU Lian-yuan1,3
DOI: 10.3964/j.issn.1000-0593.2008.05.011
Due to the high influents of the device itself and the surrounding environment, the background brightness of the digital radiography image is uniform and the image shows big noise. Therefore, in order to identify digital radiography images precisely, a further image processing is necessary. In this study, adaptive filtering, histogram equalization techniques and difference image methods were used for image processing and the results show that these techniques were useful to denoise, to intensify brightness and to rectify the background. In order to verify the feasibility of these techniques, poplar wood samples of heterogeneous material were used as experimental materials and Micro-density was measured directly by applying the linear relationship between grey scale of DR image and penetrate material density and contrasted with the result of microdensitometer. The results show these techniques were feasible and even gave a more precise measurement on wood micro-density compared to microdensitometer.
2008 Vol. 28 (05): 1186-1190 [Abstract] ( 653 ) PDF (1728 KB)  ( 524 )
1191 Research on the Fourth Generation of Saposhnikovia Divaricata by XRF
GUAN Ying1,YANG La-hu2,DING Xi-feng1,GUO Xi-hua1,ZHU Yan-ying1,SHI Jin-shan3
DOI: 10.3964/j.issn.1000-0593.2008.05.008
To cultivate oriented new varieties, Saposhnikovia divaricata seeds were carried by Shenzhou “3” satellite and filtered when they were being brought back. In the present paper, X-ray fluorescence(XRF) was used to mensurate and analyze the contents of elements of the two samples from the ground group and the 4th generation of space Saposhnikovia divaricata (space group)that have advantages in branches and leaves and yields. The contents of the main mineral elements in the two samples are the same basically. But the contents of the elements Zn, Fe, Mn and Cu from the outer group are higher than the ground group. Especially the contents of Zn, Fe, Mn and Cu concerning the curative effect in the space group increase 4.39, 1.23, 0.84 and 0.9 times as compared to the ground group. In the space group the contents and proportions of the mineral elements are improved and optimized. XRF method can be used for overall element analysis of and research on Chinese herbal medicines. Space flight breeding is an effective method for the selection of new Saposhnikovia divaricata breed.
2008 Vol. 28 (05): 1191-1193 [Abstract] ( 1947 ) PDF (396 KB)  ( 570 )
1194 Mapping Metal Elements of Shuangbai Dinosaur Fossil by Synchrotron X-Ray Fluorescence Microprobe
WANG Yi-lin1,YANG Qun1,Ablett J M2
DOI: 10.3964/j.issn.1000-0593.2008.05.009
The metal elements mapping of Shuangbai dinosaur fossil, was obtained by synchrotron x-ray fluorescence(SXRF). Eight elements, Ca, Mn, Fe, Cu, Zn, As, Y and Sr were determined. Elements As and Y were detected for the first time in the dinosaur fossil. The data indicated that metal elements are asymmetrical on fossil section. This is different from common minerals. Mapping metals showed that metal element As is few. The dinosaur most likely belongs to natural death, This is different from Zigong dinosaurs which were found dead from poisoning. This method has been used to find that metals Fe and Mn are accrete, and the same is ture for Sr and Y. This study indicated that colloid granule Fe and Mn, as well as Sr and Y had opposite electric charges in lithification process of fossils. By this analysis, compound forms can be ascertained. Synchrotron light source x-ray fluorescence is a complementary method that shows mapping of metal elements at the dinosaur fossil, and is rapid, exact and intuitionist. This study shows that dinosaur fossil mineral imaging has a potential in reconstructing the paleoenvironment and ancient geology.
2008 Vol. 28 (05): 1194-1198 [Abstract] ( 1441 ) PDF (964 KB)  ( 520 )