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2008 Vol. 28, No. 07
Published: 2008-07-29

 
       光谱学与光谱分析
1441 Effect of Red and Blue Spectrum on Photosynthesis Physiological Characteristics of Two Ecotypes of Leymus Chinensis
ZHOU Chan1,YANG Yun fei2*,WANG Kun3
DOI: 10.3964/j.issn.1000-0593.2008.07.020

Photosynthesis physiological characteristics of two ecotypes of Leymus chinensis were studied under different red and blue light excitation by LED red and blue lamp house. Photosynthesis did not carry on under red and blue light of 50 μmol·m-2·s-1. When red and blue light intensity was increased, photosynthesis rate, stoma limit value and transpiration rate of the two ecotypes of Leymus chinensis were all increased. But photosynthesis rate stopped increasing under red and blue light of 1 150 μmol·m-2·s-1 for grey green ecotype Leymus chinensis and of 907 μmol·m-2·s-1 for yellow green ecotype Leymus chinensis, which is known as light saturation. And the effect of blue light on photosynthesis became weaker than red light under higher light intensity. Increasing light intensity can promote plant photosynthesis rate in the range of low light intensity. But when light intensity reaches light saturation, photosynthesis rate does not increases but decreases. Because though light quantum numbers is increasing, the numbers of coloring mater does not change and is saturated. On the other hand, when the light intensity is of light saturation, the stoma limit value was increased and the transpiration rate was decreased in order to reduce water waste. When light intensity reaches the value that plant can bear, the plant will automatically close stoma in order to decrease transpiration and to save water. Plant balances every physiological index and makes sure that physiology damage is the least and production is the greatest. Although grey green ecotype Leymus chinensis has lower stoma limit and higher water waste, it also has higher photosynthesis rate than yellow green ecotype Leymus chinensis. And the photosynthesis capability and physiology adaptation of greygreen ecotype Leymus chinensis is greater than that of yellowgreen ecotype Leymus chinensis.

2008 Vol. 28 (07): 1441-1444 [Abstract] ( 1065 ) PDF (999 KB)  ( 1421 )
1445 Endmember Extraction Used for Hyperspectral Imagery Loss Compression
ZHANG Li-yan, CHEN De-rong, TAO Peng
DOI: 10.3964/j.issn.1000-0593.2008.07.001
One of the problems limiting the utility of hyperspectral imagery is how to compress the large number of data effectively. The current methods cannot resolve the problem of the contradiction between large compression rate and spectral information veracious reservation, even the best loss compression method can not bring the satisfying result. The paper presented a loss compression method based on the endmember extraction technology, so as to resolve the contradiction between large compression ratio and spectrum preserved accurately. The endmembers were obtained with vertex component analysis (VCA) and the fractions of them were estimated based on the proportion of cosine angle similitude between endmembers and observed spectrum. The endmembers spectrum and fraction were compressed with the lossless compression method and JPEG2000 loss compression method was used for all of the hyperspectral single-band images to increase compression ratio. The experiment on the AVIRIS data shows that compression ratio was increased greatly and the spectra were resumed effectively. When the compression ratio is 50∶1,the spectrum angle loss is about 2% for most pixels.
2008 Vol. 28 (07): 1445-1448 [Abstract] ( 1010 ) PDF (1399 KB)  ( 1205 )
1449 Study on Absorption Spectra and Optical Limiting Properties of Soluble Polymer/Multi-Walled Carbon Nanotube Composites
QIU Xue-qiong1,2,WU Hui-xia3,TONG Rui1,2,QIAN Shi-xiong1*,LIN Yang-hui3,CAI Rui-fang3
DOI: 10.3964/j.issn.1000-0593.2008.07.048
Three kinds of soluble polymer grafted multi-walled carbon nanotubes (MWNTs), including poly(N-vinylcarbazole)-MWNTs (MWNTs-PVK), polystyrene-MWNTs (MWNTs-PSt) and poly(methyl methacrylate)-MWNTs (MWNTs-PMMA) were synthesized. The TEM images of these samples show that polymers are coated outside the carbon nanotubes. The UV-Vis absorption spectra of the samples in CHCl3 were taken on a HP8452 spectrophotometer at room temperature. Compared with that of MWNTs suspension, there is a characteristic absorption peak in the ultraviolet region, which can be attributed to the polymers linked covalently with MWNTs. Their nonlinear optical properties and optical limiting (OL) performances were investigated by Z-scan method with 527 nm nanosecond laser pulses. These MWNTs dissolved in chloroform possess similar optical limiting properties, which are better than that of raw MWNT suspension and C60 in toluene solution. Nonlinear refraction, nonlinear absorption and nonlinear scattering mechanism were taken into consideration for explaining the observed results. The analysis of the experimental results shows that nonlinear absorption is the dominant mechanism behind the OL performance of these samples.
2008 Vol. 28 (07): 1449-1453 [Abstract] ( 973 ) PDF (1568 KB)  ( 1200 )
1454 Laser-Induced Isotopic Discrimination Effect in Laser Resonance Ionization Process of Lead Atom
WANG Xin-shun,LI Ying,DAI Lin, ZHENG Rong-er*
DOI: 10.3964/j.issn.1000-0593.2008.07.045
Isotope ratio measurements have been increasingly used in geochemistry, geochronology, cosmos chemistry and environmental science. Precise and accurate isotope ratio measurements are an important task in many applications such as the determination of isotope variations in geological and cosmic samples. Due to its high sensitivity, high ionization efficiency and high element selectivity, laser resonance ionization spectroscopy has nowadays become one of the key techniques, including isotope ratio measurements and trace amount analyses. Because of the isotope shifts and hyperfine structure, there is laser-induced isotopic discrimination effect in the process of laser resonance ionization. The different isotope ionization efficiency can affect precise and accurate measurement of isotope ratios. In the present paper, the dependences of the laser-induced isotopic discrimination effect on some of the laser parameters were studied by theoretical methods. Based on the numerical simulation of the population rate equations, laser-induced isotopic discrimination effect of lead isotopes was studied, by calculating laser resonance ionization transition “6s26p2 3P0—6s26p7s 3P01→ionization”. The population rate equations was approximated considering some factors which affect the probability of laser resonance transition such as spectral lines width of laser and atom, isotope shifts and hyperfine structure. According to the approximated population rate equations, “1+1” laser resonant ionization process was employed to calculate the ionization probability of lead isotopes by means of computer simulation. The dependences of laser-induced isotopic discrimination effect on the laser parameters, such as laser central wavelength, bandwidth and intensity were investigated. The calculated results show that the laser-induced isotopic discrimination effect of lead isotopes could be almost eliminated by operating at optimized wavelength and could be lessened by using wide band laser. Saturated ionization of lead isotopes was achieved by using a high intensity laser, consequently the laser-induced isotopic discrimination effect of lead isotopes could be eliminated.
2008 Vol. 28 (07): 1454-1458 [Abstract] ( 1702 ) PDF (1984 KB)  ( 779 )
1459 Selective Distribution and Physiological Function of Heterogeneous Carotenoids in Purple Photosynthetic Bacterium Rhodopseudomonas palustris
FENG Juan, LI Xue-feng, LIU Yuan
DOI: 10.3964/j.issn.1000-0593.2008.07.057
Purple photosynthetic bacterium Rhodopseudomonas (Rps.) palustris is unique in the heterogeneous carotenoid compositions in peripheral light-harvesting complex (LH2) and core complex (LH1-RC). It is of great significance to investigate selective distribution and the physiological function of various carotenoids occurring in the pigment-protein complexes mentioned above. In the present paper, high performance liquid chromatogram (HPLC) was applied to analyze the carotenoid composition in LH2 and LH1-RC complexes isolated from Rps. palustris growing in medium light intensity. Comparison of the HPLC elution profiles showed that carotenoids having 11 or 12 conjugated double bonds, including lycopene (n=11), anhydrorhodivibrin (n=12) and rhodopin (n=12), were the predominant components in LH2, whereas spirilloxanthin with n=13 was preferentially bound to core complex. The average yields of carotenoid-to-BChl energy transfer in LH2 and LH1-RC were determined by comparing their steady-state absorption spectra and NIR fluorescence excitation spectroscopy, which were normalized at the BChl Qx transition. It was found that energy transfer yield decreased from 30.9%(v=0), 25.4%(v=1) and 30.4%(v=2) in LH2 complex to 10.7%(v=0), 7.8%(v=1) and 11.4%(v=2) in LH1-RC complex, respectively. Additionally, triplet excited state carotenoids were investigated by means of sub-microsecond time-resolved absorption spectroscopy, where TnT1 transient absorption maximum was observed at 571 nm for LH1-RC and 560 nm for LH2 complex at room temperature following the photo-excitation of carotenoid at 532 nm. The dynamic curves of these two spectral components, which were assignable to carotenoids with n=13 and n=12, could be well fitted to a single exponential decay function with the apparent time constants of 1.6 and 2.2 μs, respectively. The aforementioned data suggested that heterogeneous carotenoids were selectively distributed in LH2 and core complex, where short-conjugated carotenoids in LH2 complex serve as efficient accessory light-harvesting pigments, whereas long-conjugated carotenoids preferentially bound to LH1-RC mainly perform photo-protection function.
2008 Vol. 28 (07): 1459-1463 [Abstract] ( 2571 ) PDF (1705 KB)  ( 1168 )
1464 Radiation Trapping Effect and Measurement of the Cs(6P3/2) Level Effective Radiation Rate in the Vapor Mixed with He
SHEN Xiao-yan1,DAI Kang2,SHEN Yi-fan2*
DOI: 10.3964/j.issn.1000-0593.2008.07.046
The effective radiation rate for Cs(6P3/2) resonance level in the presence of helium was determined. A cell filled with Cs metal and He at pressure PHe (0-500 Pa) was established at T=300 K. The cell was heated in the temperature range between 330 and 370 K, which produced Cs number densities approximately in the range between 1012 and 1013 cm-3. Cs atoms were excited to the 6P3/2 state using a single-mode diode laser(pump laser). The transmission of the medium at the center of the Doppler envelope of the strong h. f. component of the CsD2 line due to hyperfine pumping alone amounts to ≈5%. The assumption that has been made is that the lower-state hyperfine levels are populated in a statistical ratio. The excited-atom density and spatial distribution were mapped by monitoring the absorption of a counterpropagating single-mode diode laser beam (probe laser) tuned to the 6P3/2→8S1/2 transition which could be translated parallel to the pump beam. In the presence of radiation trapping, the spontaneous radiation rate is multiplied by the transmission factor T6P3/2→6S1/2, which describes the average probability that photons emitted within the fluorescence detection region can pass through the optically thick vapor without being absorbed. The T6P3/2→6S1/2 is related to the frequency dependent absorption cross section and the density and spatial distribution of atoms at the level of the transition. Position dependent 6P3/2 state densities were combined with the collisional broadening rate of 6P3/2←6S1/2 line due to the perturbation of both helium and cesium to yield T6P3/2→6S1/2. The effective radiation rates of the Cs D2 line as a function of the He pressure PHe were obtained. The helium caused line broadening and therefore increased the effective radiation rate. The fluorescence intensity I852 of the T6P3/2→6S1/2 emission was measured simultaneously. The measured fluorescence ratios determined the ratios of the effective radiation rates at different He density. These ratios are in agreement with theoretical evaluation.
2008 Vol. 28 (07): 1464-1467 [Abstract] ( 565 ) PDF (1158 KB)  ( 735 )
1468 Estimation of Tissue’s Blood Oxygen Parameters from Visible Absorption Spectrum of Tissues by Artificial Neural Network
DAI Li-juan1,WANG Hui-nan1,QIAN Zhi-yu1,YU Guo-qiang2
DOI: 10.3964/j.issn.1000-0593.2008.07.003
Total hemoglobin concentration (THC) and hemoglobin oxygen saturation (SO2) are essential parameters to doctors who wonder patients’ hematogenous conditions and oxygen supplies and consumptions. Instruments presently used for measuring these parameters have big size of detecting probes that limit their applications to inner bodies. An optical probe involving two fibers with source-detector separations of one hundred micrometers was developed in the present study for purpose of minimally invasive inner detecting, which uses steady-state, broadband (300-1 000 nm) light source. The source light is delivered to targets through one fiber and the reflected light from the targets is collected and transferred to a spectrometer through the other fiber. Reflectance spectrum is obtained from the spectrometer. The method of reading THC and SO2 from the reflectance spectrum was developed using liquid-tissue phantoms containing intralipid and blood. Firstly, reflex spectrum of intralipid was recorded before mixtures of intralipid and blood with different THC were made as tissue phantoms. Then the fiber optical spectrometer was used to obtain reflex spectra as the phantoms’ SO2 changed; simultaneously their corresponding THC and SO2 were recorded as the scale values by an oximeter. Differences of reflex spectra in 520-590 nm between intralipid and tissue models were proved reliably. Secondly, after data collections of absorption spectra and scale values were finished, two artificial neural networks (ANN) were build to model the relationship between scale values and absorption spectra. After being trained, the ANNs could output THC and SO2 correctly when an absorption spectrum was input. The ANNs produced errors of less than 4 μmol·L-1 for THC and 5% for SO2. In vivo and minimally invasive measurements of THC and SO2 of brain tissues in different depth were finished on 30 rats by this specific system with the ANNs. The probe was inserted stereotactically to a depth of 6 mm with measurements obtained every 0.2 mm. SO2 of gray mater and white mater of rats was respectively obtained as 0.60-0.70 and 0.45-0.55. The highest THC, 110 μmol·L-1 was measured around rat cortex. THC of brain tissue in other depth is 70-90 μmol·L-1. These values agree well with reported data. This simple, inexpensive method deserves further study to establish its efficacy for THC and SO2 measurements of inner body.
2008 Vol. 28 (07): 1468-1472 [Abstract] ( 953 ) PDF (1555 KB)  ( 1297 )
1473 Frequency Up-Conversion Properties of Er3+/Yb3+ Co-Doped Zinc Oxide Powders
WU Qun,YANG Li-wen,LIU Yun-xin,XU Chang-fu,SHANG Zhen-gang,ZHANG Yong,YANG Qi-bin
DOI: 10.3964/j.issn.1000-0593.2008.07.036
Er3+/Yb3+ co-doped ZnO powders were prepared by the high temperature sintering method with starting composition of (mol%)95ZnF2-4.8Yb2O3-0.2Er2O3. Microstructure analysis by X-ray diffraction (XRD) showed that the sample consists of two phases, i.e. ZnO and YbF3, which verified that the ZnF2 was oxidized during the high temperature sintering. Composition analysis by scanning electron microscope (SEM) and spectroscopic measurements showed that the Er3+ and Yb3+ ions were successfully used in doping the lattice of ZnO, but most of Yb3+ ions were in the YbF3 phase. These results indicated that the up-conversion luminescence was emitted from ZnO, not from YbF3. Under the excitation of 980 nm diode laser, four strong up-conversion emissions peaks centered at 658, 538, 522 and 409 nm, corresponding to the transitions 4F9/24I15/2, 4S3/24I15/2, 2H11/24I15/2 and 2H9/24I15/2, respectively, were observed. Especially, a strong red up-conversion emission was observed, which is different from that the green up-converted luminescence is dominated in glass and ceramics. Three important cross energy transfer (CRET) processes between Er3+ ions played an important role for this. Under 488 nm Ar+ laser excitation, intense violet (409 nm), weak blue (466, 450 nm) and ultraviolet (379 nm) up-conversion luminescence originating from the transitions 2H9/24I15/2, 2P3/24I11/2, 4F3/2/4F5/24I15/2, 4G11/24I15/2, respectively, were obtained. The dependence of up-conversion intensities on excitation power indicated that two-photon absorption processes were responsible for the violet luminescence under 488 nm excitation, and the violet up-converted luminescence was achieved through the forward and back energy transfer between Er3+ and Yb3+ ions. Our results show that ZnO as a host material has the potential applications in the up-conversion red phosphors and ultraviolet laser materials.
2008 Vol. 28 (07): 1473-1478 [Abstract] ( 3594 ) PDF (1953 KB)  ( 1355 )
1479 A Novel Yellow Organic Light-Emitting Device
MA Chen1,2,WANG Hua1,2,HAO Yu-ying3,GAO Zhi-xiang3,4,ZHOU He-feng1,2,XU Bing-she1,2*
DOI: 10.3964/j.issn.1000-0593.2008.07.041
The fabrication of a novel organic yellow-light-emitting device using Rhodamine B as dopant with double quantum-well (DQW) structure was introduced in the present article. The structure and thickness of this device is ITO/CuPc(6 nm)/NPB(20 nm)/Alq3(3 nm)/Alq3:Rhodamine B(3 nm) /Alq3(3 nm)/Alq3:Rhodamine B(3 nm)/Alq3(30 nm)/Liq(5 nm)/Al(30 nm). With the detailed investigation of electroluminescence of the novel organic yellow-light-emitting device, the authors found that the doping concentration of Rhodamine B(RhB) had a very big influence on luminance and efficiency of the organic yellow-light-emitting device. When doping concentration of Rhodamine B (RhB) was 1.5 wt%, the organic yellow-light-emitting device was obtained with the maximum current efficiency of 1.526 cd·A-1 and the maximum luminance of 1 309 cd·m-2. It can be seen from the EL spectra of the devices that there existed energy transferring from Alq3 to RhB in the organic light-emitting layers. When the doping concentration of RhB increased, λ max of EL spectra redshifted obviously. The phenomenon was attributed to the Stokes effect of quantum wells and self-polarization of RhB dye molecules.
2008 Vol. 28 (07): 1479-1482 [Abstract] ( 398 ) PDF (1335 KB)  ( 1205 )
1483 Synthesis and Spectral Properties of Eu2+-Doped Sr(S1-xSex) Phosphors for LEDs
ZHANG Xin-min1,2, WU Hao2, SU Qiang2
DOI: 10.3964/j.issn.1000-0593.2008.07.039
Eu2+-activated Sr(S1-xSex) phosphors were synthesized by solid-state reaction at high temperature. XRD patterns indicated that the phosphors are of single phase; the relationship between lattice constant and compositional ratio x is linear, in which the Vegard′s law holds. The excitation spectra are consistent with diffuse reflectance spectra, indicating that the energy absorbed by phosphor can be transferred to Eu2+ efficiently. The excitation spectra of these phosphors show broadband, extending from UV to visible light; and they can be matched with the emission wavelength of GaN chip well. The emission spectra exhibit characteristic 4f65d1→4f7 transition of Eu2+ ion. With increasing x the emission band shifted to shorter wavelength, which can be explained by the change in crystal field. The decay curve of fluorescence can be well fitted by double exponential equation, and the lifetime of Eu2+ is of the order of microsecond. The lifetimes are reasonable for the allowed 4f65d1→4f7 transition. The electroluminescence spectra of red LED manufactured with phosphors Sr(S1-xSex):Eu2+ were measured and the parameters of them were also measured. In a word, Sr(S1-xSex):Eu2+ are good phosphors for LED application.
2008 Vol. 28 (07): 1483-1487 [Abstract] ( 1014 ) PDF (1662 KB)  ( 1250 )
1488 Density Functional Theory Studies on Structure and Spectrum of Cu3Ti Cluster
WEI Yong-hui1,2,CHENG Jian-bo3,ZHAO Bing2*,Lombardi John R4
DOI: 10.3964/j.issn.1000-0593.2008.07.043
Bulk intermetallic Ti—Cu compounds have been found to possess special properties, including increased hardness, as well as displaying enhanced sound absorption and e shape memory. Since only one Raman progression is observed, there is not sufficient information to determine the structure of TiCu3. The different structures and vibrational frequencies of the Cu3Ti cluster were studied by means of the density functional theory with SVWN5,B3LYP and BPW91 methods at basis sets of lanl2dz, 6-31g, 6-311g, 6-311g(d), 6-311+g(2df) and 6-311+g(3d2f). The calculated results show that the ground state of the Cu3Ti cluster is a e-type structure with the C2v point group symmetry, and the bond lengths and vibrational frequencies of Cu3T are considerably dependent on the variation of basis sets. We observed only a single Raman progression in approximately 300 cm-1. This progression is most likely the totally symmetric stretch. The computed and observed Raman spectra were also compared with each other.
2008 Vol. 28 (07): 1488-1491 [Abstract] ( 2290 ) PDF (1114 KB)  ( 1295 )
1492 Tracking the Process Reconstructing Original Signal with Sampled Data by Spectroscopy
SONG Yi-zhong1,2,DONG Xiang-jun3,ZHAO Zhi-min1
DOI: 10.3964/j.issn.1000-0593.2008.07.004
With spectroscopy, the principle and process of sampling and reconstructing a continuous-time signal are discussed. A symmetrical frequency-finite spectrum function F(ω) is constructed with three modified rise-cosine pulses. Its corresponding time-domain signal f(t) is worked out theoretically. f(t) is sampled with a comb function δT(t). By modifying the value of T, Shannon sampling signal is obtained. With Fast Fourier Transform(FFT), the frequency spectrum Fd(ω) of the sampling signal is figured out. The calculated Fd(ω) is compared with the constructed F(ω). The processes to reconstruct f(t) with the sampling signal and its digital frequency spectrum Fd(ω) are discussed. As the result, there is little difference between the calculated Fd(ω) and the constructed F(ω). The original signal can accurately be reconstructed with the sampling data in time domain, so can with the frequency spectrum Fd(ω) by FFT. As soon as signal storage is concerned, we can store the sampling data or its digital frequency spectrum.
2008 Vol. 28 (07): 1492-1495 [Abstract] ( 1014 ) PDF (2044 KB)  ( 1476 )
1496 Nondestructive Detection of Grey Mold of Eggplant Based on Ground Multi-Spectral Imaging Sensor
WU Di1,ZHU Deng-sheng2,HE Yong1,ZHANG Chuan-qing3,FENG Lei1*
DOI: 10.3964/j.issn.1000-0593.2008.07.051
Botrytis cinerea Pers. is a worldwide fungus. It is a severe threat to eggplant. Chemistry methods can do an accurate identification, however they are time-consuming, require execution by professionals and are high cost. The present paper presents the development of a ground based multi-spectral imaging sensor for the grey mold detection. Three channels (green, red, near-infrared) of crop images were acquired. Two algorithm systems were developed. The objective of the image processing is to obtain a binary image, which could point out the location of symptoms as accurately as possible. Two image processing methods were developed. It could be seen that method 1 can diagnose the symptoms accurately even if the symptoms are small while method 2 can only diagnose the symptoms with a certain extent area and the detection of symptoms is not very accurate. However, the images processed by method 1 showed some error diagnoses while the method 2 did not. It was concluded that both methods have some advantages and disadvantages. In the agriculture practice, the diagnosis environment will be more complex than in the greenhouse. Some things such as dry soil and perished leaf fragment will disturb the symptom detection by naked eyes when the grower stands away from the leaf. Two image process methods can diagnose the symptoms clearly although the position based on method 2 was a little deviated. It was concluded that the symptoms were well detected using multi-spectra imaging technique even there were some disturbances. Thus, multi-spectral imaging technique is available for the symptoms detection of grey mold on eggplant leaves.
2008 Vol. 28 (07): 1496-1500 [Abstract] ( 616 ) PDF (1693 KB)  ( 715 )
1501 FTIR Spectra Analysis of the Reactive Activity of Lignin When Modified by Laccase
QIU Wei-hua, CHEN Hong-zhang*
DOI: 10.3964/j.issn.1000-0593.2008.07.038
In company with the development of nonaqueous enzymology, the enzymatic modification of lignin has gained increasing interests, especially in the synthesis of high molecular material. In the present article, the enzymatic modification of spruce alkali lignin in cetyltrimethylammonium bromide (CTAB) reversed micelles (100 mmol·L-11, pH 6.0, W/O=40), alcohol lignin in ethanol solution (50%), lignin sulphonate in sodium phosphate buffer (pH 5.8, 20 mmol·L-1) and steam-explosion wheat straw alkali lignin in alkaline solution (pH 10.0, 20 mmol·L-1 NaOH) by mycelia sterilia YY-5 laccase was studied. Laccase was isolated from Mycelia Sterilia YY-5 (CGMCC-1462) which was an entophytic fungus of Rhus Chinensis Mill. FTIR spectrum was used to assay the structure of lignins and gel permeation chromatography (GPC) was used to determine the molecular weight and molecular weight polydispersity of lignins. Bands of lignin in FTIR spectra of all lignins changed obviously after treated with YY-5 laccase, which indicated that some bond breakage or rearrangement occurred to lignin. The shift of non-conjugated C=O and conjugated carbonyl groups (α-carbonyl groups) stretching vibration, the decrease of phenol hydroxyl stretching vibration and the increase of C—O—C stretching vibration of ester bond proved that phenolic hydroxyl, carbonyl group and side chain substituent all might participate in the laccase modification reactions of lignin. Meanwhile, the results of GPC indicated that the molecular of lignins all have certain increase and molecular polydispersity decreased. From the point of the molecular mass polydispersity, the modification effect of YY-5 laccase on steam-exploded wheat straw alkali lignin and spruce alkali lignin was more significantly than other two lignins. The molecular mass polydispersity for steam-exploded wheat straw alkali lignin and spruce alkali lignin was 1.211 and 1.375 respectively, which might contribute to the alkali-stable enzyme for YY-5 laccase. Correspondingly, alkali solution was chosen as the optimum medium for YY-5 laccase to modify lignins.
2008 Vol. 28 (07): 1501-1505 [Abstract] ( 1486 ) PDF (1369 KB)  ( 775 )
1506 Vibration Spectra and Genetic Type of Cassiterites
LIU Yan1,SHEN Zhang-wu2,DENG Jun1,JIANG Shao-qing1
DOI: 10.3964/j.issn.1000-0593.2008.07.050
Trace elements determination of cassiterites from Furong ore field indicates that there is a certain amount of Fe, Mn and Ti elements in cassiterite. The mean of unit-cell parameters for cassiterite is 7.165(nm3) by the method of XRD analysis and the unit-cell parameter which also indicates that the genetic type of the ore field belongs to cassiterite-sulfide type, is bigger than that of other genetic type. Four IR active vibration frequencies in cassiterite samples also suggest that the IR spectra of cassiterites from Furong ore field belongs to deformed spectra suggesting that the genetic type of cassiterite from Furong ore field is mainly of cassiteriate-sulfur type. The Raman frequency of A1g peak has typomorphic significance to study its genetic type. A1g is a characteristic peak of cassiterite and AO2 oxide of the same structure style. Impure elements of cassiterite remarkably affect its Raman frequency which will move to low frequency if the contents of Nb and Ta reach a certain amount. In Furong ore field, A1g frequency of casstiterite is about 632 cm-1 which is bigger than other cassiterites of various genetic types and the implication and character of Raman spectra are consistent with the cell parameters and IR analysis of these samples. Combined with the study of chemical composition and crystal structure, the IR spectra and Raman spectra can mean a lot for the analysis of genetic type of the cassiterite.
2008 Vol. 28 (07): 1506-1509 [Abstract] ( 2371 ) PDF (1423 KB)  ( 619 )
1510 Study on the Influence of Temperature on Near Infrared Spectra
JIANG Huan-yu,XIE Li-juan,PENG Yong-shi,YING Yi-bin*
DOI: 10.3964/j.issn.1000-0593.2008.07.002
Near-infrared (NIR) spectroscopy technique is one of qualitative and quantitative analysis techniques that were developed quickly in recent years. However, the characteristic of NIR spectral region determines its low absorbance, low sign-to-noise and peak overlapping, which results in the phenomenon that th NIR spectrum is affected by sample source, sample varieties, sample state, location and sample temperature and uncertainty of spectrum. In this paper, the influence of temperature on NIR spectra was studied and calibration and validation models of chlorophyll at different temperatures were built. The results show that temperature does have effect on the model precision. High precision could be achieved at 10 and 20 ℃ and the former was the best though using more principal components. Calibration and validation precisions of models were poor when it was 25 ℃. At the same time, spectra obtained at different temperatures were classified using discriminate analysis. It was found that the spectra were misclassified exception ones obtained at 20 ℃ which meant that there were not clear differences between the spectra exception the ones at 20 ℃. The primary research work about the condition and application of detecting leaves was studied which helps to provide theory foundation for proposing temperature modification model in the future.
2008 Vol. 28 (07): 1510-1513 [Abstract] ( 2639 ) PDF (1346 KB)  ( 1279 )
1514 Synthesis of Pyridine-Containing Diacylhydrazones and Study on Their Spectral Properties
LI Dong-feng1,LU Zi-kai1, LI Min2
DOI: 10.3964/j.issn.1000-0593.2008.07.021
Organic electroluminscent (OEL) technology has revealed the great potential application in flat panel display, and has attracted much interest all over the world. In order to create more efficient and high performance device, new materials with high electron transporting capability were demanded. Schiff base complexes can be employed as emitting materials to fabricate electroluminescent device. Several pyridine diacylhydrazones compounds were synthesized. The structure of compounds was confirmed by IR, fluorescence spectrum and elementary analysis. The fluorescence spectra showed that these compounds have good fluorescence. The fluorescence emission wavelengths are between 420 and 440 nm, the fluorescence intensity is related to the substituent of the compounds. The substituent of —OH, furan and piperonal donate electrons that lead to the red shift of fluorescence.
2008 Vol. 28 (07): 1514-1517 [Abstract] ( 2490 ) PDF (1318 KB)  ( 1503 )
1518 Study on Spectrum of Solvent Extraction of Chromium(Ⅵ) by Primary Amine
LIN Xiao1,2,CAO Hong-bin1*,ZHANG Yi1
DOI: 10.3964/j.issn.1000-0593.2008.07.022
The Cr(Ⅵ) solvent extraction in near neutral aqueous solution by primary amine was experimentally studied by the inductively couple plasma-atomic emission spectrometry (ICP-AES), laser Raman spectroscopy,Fourier transform infrared spectroscopy (FTIR) and 1H nuclear magnetic resonance spectroscopy (1H NMR). The ICP-AES analysis of the aqueous phase before and after solvent extraction showed that primary amine could extract Cr(Ⅵ) from nearly neutral solution. Laser Raman spectroscopy of loaded organic phase showed that a new peak appeared at 890 cm-1 after Cr(Ⅵ) was extracted by primary amine. FTIR showed the process that primary amine extracted Cr(Ⅵ) from nearly neutral aqueous solutions was different from anion exchange mechanism, and the Cr(Ⅵ) extracted into the organic phase resulted in the appearance of the peak at 885 cm-1 of FTIR which justified that the peak at 890 cm-1 of Raman was caused by Cr(Ⅵ). The 1H NMR spectroscopy showed that the value of chemical shift of protons of —NH2 decreased after extraction, and it is believed that primary amine was associated with Cr(Ⅵ) through hydrogen bonding. On the basis of the spectroscopic analysis results above, the the mechanism of Cr(Ⅵ) extraction by primary amine from nearly neutral aqueous solutions was believed to be solvation with molecular association between primary amine and Cr(Ⅵ) through hydrogen bonding.
2008 Vol. 28 (07): 1518-1521 [Abstract] ( 361 ) PDF (1340 KB)  ( 1173 )
1522 DSC and Temperature-Dependent Infrared Spectroscopic Study of Hydrogen-Bonded Liquid Crystal Complexes
WEI Qiang,CAO Hui,ZHANG Li-pei,YUAN Xiao-tao,YANG Huai*,WANG Yan-bin
DOI: 10.3964/j.issn.1000-0593.2008.07.019
The hydrogen-bonded liquid crystalline complexes based on 4’,4-bipyridine and 4-(trans-4-propylcyclohexyl)benzoic acid and trans-4-(trans-4-propylcyclohexyl)cyclohexyl carboxylic acid assigned as PCBA-BPy and PCCA-BPy were prepared and measured by polarized optical microscopy (POM), differential scanning calorimeter (DSC) and temperature-dependent FTIR. It was found that PCBA-BPy and PCCA-BPy exhibited both smectic and nematic phase while all of their predecessors showed no smectic phase. The temperature-dependent FTIR studies revealed that the hydrogen bonding in complex PCBA-BPy was very different from that in PCCA-BPy. The wave number of C=O band had an obvious change at the crystal 1-crystal 2 transition but almost didn’t change at smectic-nematic and nematic-isotropic transition; while in PCCA-BPy, it showed no sudden changes but shift to 1 709 cm-1 gradually with the increase in temperature. The results from temperature-dependent FTIR studies also revealed that when the temperature was higher than the clearing point of the complexes, both of the complexes decomposed partially.
2008 Vol. 28 (07): 1522-1525 [Abstract] ( 1993 ) PDF (1503 KB)  ( 785 )
1526 FTIR Spectroscopic Studies of Inner Stress on Boron Carbon Nitride Thin Films
WANG Yu-xin1,ZHENG Ya-ru1,SONG Zhe1,FENG Ke-cheng2,ZHAO Yong-nian3
DOI: 10.3964/j.issn.1000-0593.2008.07.027
Boron carbon nitride thin films were deposited by radio frequency (RF) magnetron sputtering technique using a 50 mm-diameter composite target consisting of h-BN and graphite in an Ar-N2 gas mixture. The composite target was composed of two semi disks:one of h-BN and the other one of graphite. The distance between the target and the substrate was kept at 50 mm. The chamber base pressure was below 5×10-4 Pa. During the deposition, the mixture of Ar (80%) and N2 (20%) was injected into the vacuum chamber and the total pressure was 1.3 Pa. The films were grown on silicon substrates at different deposition parameters, including sputtering power of 80-130 W, deposition temperature of 300-500 ℃ and deposition time of 1-4 h. The chemical bonding state of the samples was characterized by Fourier transform infrared absorption spectroscopy (FTIR). The results suggested that all of the films deposited at these deposition parameters are atomic-level hybrids composed of B, C and N atoms. Besides BN and carbons bonds, the boron carbide and carbon nitride bonds were formed in the BCN thin films. And the deposition parameters have important influences on the growth and inner stress of BCN thin films. That is the higher the sputtering power, the larger the inner stress; the higher or lower the deposition temperature, the larger the inner stress; the longer the deposition time, the larger the inner stress. So changing deposition parameters properly is a feasible method to relax the inner stress between the films and substrate. In the conditions of changing one parameter each time, the optimum deposition parameters to prepare BCN thin films with lower inner stress were obtained: sputtering power of 80 W, deposition temperature of 400 ℃ and deposition time of 2 h.
2008 Vol. 28 (07): 1526-1529 [Abstract] ( 938 ) PDF (1164 KB)  ( 1176 )
1530 Online Soft Sensing Method for Freezing Point of Diesel Fuel Based on NIR Spectrometry
WU De-hui1,2
DOI: 10.3964/j.issn.1000-0593.2008.07.016
To solve the problems of real-time online measurement for the freezing point of diesel fuel products, a soft sensing method by near-infrared (NIR) spectrometry was proposed. Firstly, the information of diesel fuel samples in the spectral region of 750-1 550 nm was extracted by spectrum analyzer, and the polynomial convolution algorithm was also applied in spectrogram smoothness, baseline correction and standardization. Principal component analysis (PCA) was then used to extract the features of NIR spectrum data sets, which not only reduced the number of input dimension, but increased their sensitivity to output. Finally the soft sensing model for freezing point was built using SVR algorithm. One hundred fifty diesel fuel samples were used as experimental materials, 100 of which were used as training (calibrating) samples and the others as testing samples. Four hundred and one dimensional original NIR absorption spectrum data sets, through PCA, were reduced to 6 dimensions. To investigate the measuring effect, the freezing points of the testing samples were estimated by four different soft sensing models, BP, SVR, PCA+BP and PCA+SVR. Experimental results show that (1)the soft sensing models using PCA to extract features are generally better than those used directly in spectrum wavelength domain; (2)SVR based model outperforms its main competitors-BP model in the limited training data, the error of which is only half of the latter; (3)The MSE between the estimated values by the presented method and the standard chemical values of freezing point by condensing method are less than 4.2. The research suggests that the proposed method can be used in fast measurement of the freezing point of diesel fuel products by NIRS.
2008 Vol. 28 (07): 1530-1534 [Abstract] ( 871 ) PDF (1635 KB)  ( 1438 )
1535 Micro-FTIR Study on Structure of Macerals from Jurassic Coals in Northwestern China
CHANG Hai-zhou1,2,ZENG Fan-gui1*,LI Wen-ying1, LI Jun1,2,JIA Jian-bo1,XIE Ke-chang1
DOI: 10.3964/j.issn.1000-0593.2008.07.015
Jurassic coal in Northwest China is rich in resources and it is a necessary premise to reveal the chemical structure characteristics of the coal macerals in this region before the coal is put into reasonable and efficient use. Micro-FTIR technique was used to investigate the chemical composition and structures of vitrinite semifusinite and fusinite from Jurassic coal in Northwestern China. The results show that vitrinite and semifusinite have more aliphatic hydrogen, but fusinite has more aromatic hydrogen and C=O structure. The aliphatic hydrogen in semifusinite is higher than that in fusinite and it is this structure characteristic of semifusinite that led to the richer inertinite but higher reactivity of the Northwestern China coal. Not only vitrinite but also semifusinite and fusinite with weaker reducibility have less aliphatic hydrogen and more C=O structures than those with stronger reducibility. The different intensity of oxidation in the process of coalification is one of the causes that led to different type of reducibility.
2008 Vol. 28 (07): 1535-1538 [Abstract] ( 236 ) PDF (1549 KB)  ( 665 )
1539 Application of Near-Infrared Spectroscopy in Golf Turfgrass Management
LI Shu-ying, HAN Jian-guo*
DOI: 10.3964/j.issn.1000-0593.2008.07.037
The management of golf course is different from other turfs. Its particularity lies in its higher and more precise requirement during maintenance compare with other turfs. In case something happened to turf of golf course, more effective and higher speed detecting and resolution are required. Only the data about turf growth and environment were mastered precisely in time, the friendly environmental and scientific management goal could be completed effectively and economically. The near infrared spectroscopy is a new kind of effective, convenient and non-destructive analytical method in the turfgrass management of golf course in recent years. Many factors of turf-soil system in golf course could be determined by near infrared spectroscopy at the same time. In this paper, the existing literature that use of near infrared spectroscopy to study turfgrass and soil nutrient content, soil hygroscopic moisture, feasible fertilizer application time and rate, to fix the time and volume of irrigation, turfgrass visual quality evaluation, turfgrass disease prediction and prevention were reviewed. Most researchers considered the nutrition condition of turf impacted the visual and playing quality of golf course directly and then indirectly influenced most of assistant cultivation such as fertilization, mowing and irrigation and so on. The using of NIRS can detect the nutrient content of turfgrass effectively and estimate the nutrient is excessive or deficient quickly. And then the feasible time and rate of fertilizers can be decided. Comparing with the common judgment ways based on the season fertilization and visual estimation, the using of NIRS can reduce the application of fertilizers on the base of keeping the same turf quality simultaneously. NIRS can analysis many items of soil such as moisture, elements concentration, textures on the spot by the thousands. This method can get lots of cover-all data non-destructively. What’s more, NIRS can analysis soil betimes quickly. NIRS is cheap and simply to operate. Many spectral data of many chemical constituents can be determined only through scanning once. Except for detecting the nutrient concentration of turf or soil, NIRS can analysis the textures and pH of soil and so on. NIRS can analysis the moisture content of soil on the spot quickly and be helpful to decide the right time and mass of irrigation. NIRS can also be used of appraising visual quality of turf including turf color, density, uniformity and cover and so on. And then the quantitative indexes of visual quality of turf can be drawn. NIRS can help analysis the condition of the plant diseases and insect pests and adopt some prevention and cure measure effectively. As a consequence, the negative reaction on environment is avoided because of spraying bactericide and pesticide blindly. The using of near infrared spectroscopy could be helpful of obtaining the data about the turgrass and environment in golf course and contributed to improve turfgrass management and decision-making effectively. Nowadays some problems baffled the far and wide use of near infrared spectroscopy in golf course. Its widely use needs to accumulate the basic chemical analytical data about the golf course. In addition, another problem need to solve is how to ascertain the ground biomass of turfgrass. It is required for NIRS use widely to invent more portable and ’on-the-go’ golf course using near infrared spectroscopy apparatus. Together with the more and deeper research on NIRS, new NIRS apparatuses will come up and the application software of NIRS will be upgraded. NIRS will play a more important role in turf management of golf course.
2008 Vol. 28 (07): 1539-1543 [Abstract] ( 2716 ) PDF (938 KB)  ( 1322 )
1544 Recent Progress in NIR Spectroscopy Technology and Its Application to the Field of Forestry
GONG Yu-mei1,ZHANG Wei2
DOI: 10.3964/j.issn.1000-0593.2008.07.040
Near-Infrared Spectroscopy (NIRS) is the most rapidly developing and the most noticeable spectrographic technique in the 80’s (the last century). Its developing history and utilization in foreign countries were introduced. The authors mainly summarized the applications of NIRS to the field of forestry. The applications of near-infrared reflectance spectroscopy (NIRS) in fruit quality, timber and seed quality analysis are more active in forestry due to its rapid, timely, less expensive, non-destructive, straightforward analytic characteristics. In the last two decades, non-destructive methods using near-infrared spectroscopy (NIRS) to evaluate parameters for estimating maturity were applied to different fruits species to check the ripening status of fruits on trees or to grade fruits in the packing house, to assess fruit quality, such as sugar and acid contents, soluble solids, firmness of fruit, offers great advantages to growers in deciding when to harvest. The near infrared spectrophotometry (NIRS) can also be used the nondestructive quantitative assessment of the solid wood density, the moisture condition and the lignin content in bulky wood. The previous results indicated that the utility of NIRS was a selection tool in breeding programs, for example, three kids of persimmon fruits, astringent, non-astringent and half-astringent, were clearly classified by using Near-infrared (NIR) methods, and based on the combination of near infrared technology and multivariate analysis, the genetic, physiological and technical qualities of both temperate and tropical tree species on single seed basis can be characterized. It has already been shown that NIRS can predict the chemical composition of litters. NIRS is also capable of correlating the initial spectral characteristics of the litters with their short-and medium-term decomposability. The stage of decay of decomposing leaves can be predicted by using the near infrared reflectance spectroscopy. The method is rich in information and quick to conduct. However, the applications of NIRS to the field of forestry in our country are only on the beginning, and are mainly focused on wood characteristics and fruit quality testing. In fact, there are still some further applications of NIRS in forestry in future, such as analyzing trace elements in fruit, biosecurity inspection. In this paper, the authors analyzed the NIRS applications status in home and abroad, and discussed the applied prospects to promote its applications to the field of forestry research and practical programs in our country.
2008 Vol. 28 (07): 1544-1548 [Abstract] ( 630 ) PDF (940 KB)  ( 806 )
1549 Applications of Near-Infrared Spectroscopy to Analysis of Traditional Chinese Herbal Medicine
LI Yan-zhou,MIN Shun-geng,LIU Xia*
DOI: 10.3964/j.issn.1000-0593.2008.07.047
Analysis of traditional Chinese herbal medicine is of great importance to its quality control. Conventional analysis methods can not meet the requirement of rapid and on-line analysis because of complex process more experiences or needed. In recent years, near-infrared spectroscopy technique has been used for rapid determination of active components, on-line quality control, identification of counterfeit and discrimination of geographical origins of herbal medicines and so on, due to its advantages of simple pretreatment, high efficiency, convenience to use solid diffuse reflection spectroscopy and fiber. In the present paper, the principles and methods of near-infrared spectroscopy technique are introduced concisely. Especially, the applications of this technique in quantitative analysis and qualitative analysis of traditional Chinese herbal medicine are reviewed.
2008 Vol. 28 (07): 1549-1553 [Abstract] ( 3429 ) PDF (1081 KB)  ( 3033 )
1554 The Rapid Analysis of Fatty Acids in Vegetable Oils by Near Infrared Spectrum
YU Yan-bo1,ZANG Peng1,FU Yuan-hua1,ZHANG Lu-da2,YAN Yan-lu3,CHEN Bin1*
DOI: 10.3964/j.issn.1000-0593.2008.07.042
In this research, The functional components of vegetable oils were analyzed by near infrared(NIR) spectral technology. The optimum conditions of mathematics model of four components(C16:0,C18:0,C18:1,C18:2)were studied, including the sample set selection, chemical value analysis, the detection methods and condition. Chemical value was analyzed by HPLC. 52 samples were selected, 41 for modeling set and 11 for testing set. All samples were placed in 5mm thick sample pools and swept by near infrared(NIR) with discrimination factor 8 cm-1 without any other disposal. Using PLS methods sated model. Data were processed by first derivative method and centering method. 5 000-9 000 cm-1 spectral region was analyzed. Correlating index (r), RMSECV and RMSEP were chose as evaluation index. The result demonstrated that the correlation between the reference value of the modeling sample set and the near infrared predictive value were r(C16:0)=0.891, r(C18:0)=0.837, r(C18:1)=0.982, r(C18:2)=0.971, respectively. And the correlation between the reference value of the testing sample set and the near infrared predictive value were 0.921, 0.891, 0.946 and 0.949, respectively. It proved that the near infrared predictive value was linear with chemical value and the mathematical model established for components of vegetable oils was feasible. For validation, 8 unknown samples were selected to be analysis by infrared(NIR). The result demonstrated that error between predict value and chemical value was less than 10%. That was to say infrared (NIR) had a good veracity in analysis components of vegetable oil. Because infrared(NIR) spectral technology is convenient, rapid than HPLC in oil components analysis, moreover, infrared(NIR) can analyze many components at the same time. It must have great application prospect in vegetable oil components analysis.
2008 Vol. 28 (07): 1554-1558 [Abstract] ( 1983 ) PDF (1634 KB)  ( 782 )
1559 FTIR, FT-Raman and Surface Enhanced Raman Study of Shikimic Acid
YU Dan-ni,ZHOU Guang-ming*,LI Si,YANG Da-cheng
DOI: 10.3964/j.issn.1000-0593.2008.07.044
The authors reported the FT-infrared, and FT-Raman spectra of shikimic acid in solid state and in saturated liquid state in the present article. The vibrational peaks of each group in the molecular structure of shikimic acid were obtained and assigned, and furthermore, the Raman and IR vibrational shifts of the corresponding groups in the molecular structure of shikimic acid were analyzed and speculated especially. As shikimic acid mixed with silver nanoparticle the SERS-active substrate, and was adsorbed on the surface of the silver nanoparticle, we also obtained the surface enhanced Raman scattering (SERS) spectra of shikimic acid at different concentrations from 1.0×10-1 to 1.0×10-5 mol·L-1, further more the adsorption state and the adsorption characteristics of shikimic acid, adsorbed on the surface of the silver nanoparticle, were studied and speculated with the SERS method and the surface selective rule together. Strong Raman signals were detected in the experiments and each group’s vibrations in the molecular structure of shikimic acid were resolved with the combination of FT-infrared and FT-Raman spectroscopy. From the experiment data, the ideal optimized concentrations range is lower than 1×10-3 mol·L, among which we could obtain better SERS spectra. Still, the experimental results suggested that the groups in the molecule structure of shikimic acid, such as COO-, OH-, CH2 and so on, can interact and be absorbed tightly with the surface of silver nanoparticle, and this interaction and absorption were mainly through the SERS charge transfer process mechanism of hydroxyl and carboxyl, and SERS electromagnetic process mechanism of methylene and hypomethyl together with the surface of silver nanopartical. The vibrations of alkene’s C=C bond on the ring of cyclohexene in the molecule structure of shikimic showed no obvious enhancement in SERS spectra, which indicated that alkene’s C=C bond on the ring of cyclohexene in the molecule structure of shikimic acid had no effective interaction and adsorption on the surface of silver nanoparticle according to the surface selective rule.
2008 Vol. 28 (07): 1559-1563 [Abstract] ( 2030 ) PDF (1467 KB)  ( 615 )
1564 Raman Spectroscopic Study of Binary PbO-TeO2 Glasses
HUANG Li,YOU Jing-lin*,CHEN Hui,JIANG Guo-chang
DOI: 10.3964/j.issn.1000-0593.2008.07.023
Raman spectra of lead tellurite glasses and their melts were measured. Results show that four coordinate tellurite units convert into three coordinate units with increasing the concentration of PbO, and the number of non-bridging oxygen bonds (NBO) increases accordingly in this system. Three spectral peaks in the high frequency range were assigned to stretching vibration of bridging oxygen in four coordinate tellurite units (Qb), stretching vibration of non-bridging oxygen in four coordinate tellurite units (Qnb) and in three coordinate tellurite units (Tnb). The relative density of four coordinate structure units decreases and the three coordinate tellurite units considerably exist in tellurite glasses when the concentration of PbO>50%. Besides, the Raman frequencies of the three species’ peaks become blue-shifted because of the temperature induced crystallization at high temperature, and the peak intensities increase and the peaks sharpen. The peaks merge together and become much broader while the glass is heated above the melting point because of multiple microstructure units coexisting.
2008 Vol. 28 (07): 1564-1568 [Abstract] ( 1302 ) PDF (1795 KB)  ( 612 )
1569 Study of Cubic Boron Nitride Crystal UV Absorption Spectroscopy
LIU Hai-bo1,JIA Gang1,CHEN Gang2,MENG Qing-ju1,ZHANG Tie-chen3
DOI: 10.3964/j.issn.1000-0593.2008.07.005
UV absorption spectroscopy of artificial cubic boron nitride (cBN) single crystal flake, synthesized under high-temperature and high-pressure, was studied in the present paper. UV WINLAB spectrometer was used in the experiments, and MOLECULAR SPECTROSCOPY software was used for data analysis. The UV-cBN limit of 198 nm was showed in this test by a special fixture quartz sample. We calculated the energy gap by virtue of the formula:λ0=1.24/Eg (μm). The energy gap is 6.26 eV. There are many viewpoints about the gap of cBN. By using the first-principles theory to calculate energy band structure and density of electronic states of cBN, an indirect transition due to electronics in valence band jumping into conduction band by absorbing photon can be confirmed. That leads to UV absorption. The method of calculation was based on the quantum mechanics of CASTEP in the commercial software package of Cerius2 in the Co. Accerlrys in the United States. The theory of CASTEP is based on local density approximation or gradient corrected LDA.The crystal parameter of cBN was input to the quantum mechanics of CASTEP in order to construct the crystal parameter model of cBN. We calculated the energy gap of cBN by the method of gradient corrected LDA. The method underestimates the value of nonconductor by about 1 to 2 eV. We gaot some opinions as follows:cBN is indirect band semiconductor. The energy gap is 4.76 eV, less than our experiment. The reason may be defect that we ignored in calculating process. It was reported that the results by first principles method of calculation of the band generally was less than the experimental results. This paper shows good UV characteristics of cBN because of the good agreement of experimental results with the cBN band width. That is a kind of development prospect of UV photo-electronic devices and high-temperature semiconductor devices.
2008 Vol. 28 (07): 1569-1572 [Abstract] ( 1407 ) PDF (1120 KB)  ( 731 )
1573 Properties of Synthesized CdS Nanoparticles by Reverse Micelle Method
LI Heng-da1,WANG Qing-wei1*,ZHAI Hong-ju1,LI Wen-lian1, 2
DOI: 10.3964/j.issn.1000-0593.2008.07.017
Micelle system with reverse phase (water/CTAB/n-hexyl alcohol/n-heptane) is a weenie liquid-globelet of surface active agent molecule which can be stably and uniformly dispersed in continuous oil medium. The micelle system with reverse phase can work as a “micro-reactor” to synthesize CdS nano-particle with excellent performance. In the present article considering the effects of W value (W=[water]/[surface agent]) of the micelle system with reverse phase, we observed that the ratio of [Cd2+] and [S2-] ions to the original concentrations of the Cd2+ and S2- ions can affect the luminescent properties of CdS nano-particle. Using regurgitant treatment process the surface of CdS nano-particle can be modified, and as a result the defect emission was reduced and even disappeared, but exciton emissions markedly increased. On the other hand, a red-shift of the exciton emission peak with the increase in the particle size was observed, indicating considerable quantum confinement effect. A maximum quantum efficiency of 11% for the synthesized CdS nano-material was achieved.
2008 Vol. 28 (07): 1573-1577 [Abstract] ( 882 ) PDF (1606 KB)  ( 707 )
1578 Detection of Antioxidative Capacity of Bamboo Leaf Extract by Scavenging Organic Free Radical DPPH
GUO Xue-feng,YUE Yong-de*,TANG Feng,WANG Jin,YAO Xi
DOI: 10.3964/j.issn.1000-0593.2008.07.032
By studying on absorption spectrum of DPPH solution and DPPH reaction system, the conclusion was drawn as follows, the wavelength for the determination of DPPH reaction system by spectrophotometric method was chosen to be 518.4 nm, DPPH reaction system was 4.00 mL of 257.7 mg·L-1 DPPH+1 mL of antioxidant solution with the reaction time of DPPH reaction system of 40 min. The relation between DPPH radical scavenging rate and the concentration of TBHQ and BHT was studied, and IC50 (the value of antioxidant concentration for scavenging half of DPPH radical) was used as the index to evaluate scavenging capacity. The determining IC50 values were as follows: TBHQ(21.14 mg·L-1),BHT(42.09 mg·L-1) and M40(108.40 mg·L-1). Bamboo leaf extract could be used as natural antioxidant.
2008 Vol. 28 (07): 1578-1582 [Abstract] ( 1591 ) PDF (1932 KB)  ( 639 )
1583 Study on Spectral and Immune Identification of Artificial Antigen of Bisphenol A
ZHENG Jie,ZHANG Kun,ZHAO Su-qing*
DOI: 10.3964/j.issn.1000-0593.2008.07.052
Bisphenol A(BPA) is able to mimic the effects of endogenous hormones and it influences the central nervous system in human being. In recent years, BPA has largely arisen because it is released into our environment from many kinds of the poly-carbonate plastics and epoxy resins of food cans. Because trace residual amount of BPA might be harmful to human being, many instrument analysis methods have been developed for the determination of BPA. But these instrument analysis methods require complicated pre-treatment steps and do not suit rapid processing of multiple samples. Gold-labeled immunochromatography assay method can provide in situ monitoring of trace BPA in ground-water and drinking water. In order to build the simple and fast gold-labeled immunochromatography assay method, it is necessary to synthesize and identify artificial antigen of BPA firstly. The modified BPA was conjugated with the carrier of bovine serum albumin (BSA) by EDC·HCl, after dialyzed, the synthesized artificial antigen of BPA was lyophilized, and then stored at -20 ℃. Three methods such as UV and IR spectra scanning and immunoassay were used to determine whether artificial antigen of BPA had been synthesized. The results showed that UV spectrum of artificial antigen of BPA has one absorbance band at 278 nanometers (nm) which is the characteristic absorbance band of the carrier of bovine serum albumin, and another absorbance band at 226 nm which is the characteristic absorbance band of BPA. The IR spectrum absorbance bands of bovine serum albumin and BPA appeared on the IR spectrum graph of artificial antigen of BPA, moreover, shrinked vibration bands at 1 000-1 300 cm-1 showed that a C—N bond was produced and suggested that the modified BPA and BSA had been linked. The antibody of anti- BPA was raised in sera of immunized Balb/c mice by indirect competitive ELISA. So the above results showed that the artificial antigen of BPA was synthesized successfully. The artificial antigen of BPA can be used to develop monoclonal antibody of anti-BPA and also to prepare gold-labeled immunochromatography assay method for in situ monitoring of BPA in the future.
2008 Vol. 28 (07): 1583-1586 [Abstract] ( 1556 ) PDF (1254 KB)  ( 716 )
1587 Research on the Interaction of Cr(Ⅲ) Complex of Genistein with DNA
YU Yan-ying1,LI Hua1,HU Xin1,CAO Shu-wen2*
DOI: 10.3964/j.issn.1000-0593.2008.07.054
The interaction of the Cr(Ⅲ) complex of genistein (GEN-Cr) with calf thymus DNA (ctDNA) in Tris (pH 7.2) buffer was investigated using UV spectra, DNA melting, fluorescence spectra and viscosity. From the absorption titration experiment, no obvious red shift was found, but the notable hypochromicities were observed. When cDNA/cGEN-Cr=3, the ππ* transitions of the complex at 272 nm showed a decrease in intensity of 29.1%, which indicated that there was remarkable intercalation between complex and DNA base pairs, involving a strong π-stacking interacting between them. The binding constant for the complex was K=1.9×105 mol·L-1. From the melting curves of ctDNA in the absence and presence of the complex, the melting temperature of ctDNA was found to increase by 5.5 ℃ from 74 to 79.5 ℃, owing to the increased stability of the helix in the presence of the complex that was intercalated into the double helix. The complex could emit weak luminescence in Tris buffer. The emission intensity of the complex at 340 nm increased steadily with the addition of ctDNA. The result suggested that the complex got into a hydrophobic environment inside the DNA and avoided the effect of solvent water molecules. The strong interaction of the complex and ctDNA also resulted in greatly enhanced intensity of the resonance light scattering spectra. The emission intensity of DNA-EB system at 600 nm decreased remarkably with increasing the complex concentration, which indicated that the complex could be intercalated into DNA and replace EB from the DNA-EB system. According to the classical Stern-Volmer equation, the quenching plots at 25 and 37 ℃ both appeared approximately linear. These results showed that there was one predominant quenching style in this process. Viscosity experiments were carried out by an Ubbelodhe viscometer at 20.0(±0.1)℃. The relative viscosity of ctDNA increased steadily with the increas in the complex. The result clearly showed that the complex could be intercalated between DNA base pairs, causing an extension of the helix, and thus increased the viscosity of DNA. The results above indicated that there is a relatively strong interaction between the GEN-Cr complex and ctDNA, and the complex could bind ctDNA mainly by intercalation. The research suggested that the GEN-Cr complex may be a promising candidate for anticancer, which deserves further research.
2008 Vol. 28 (07): 1587-1591 [Abstract] ( 454 ) PDF (1640 KB)  ( 684 )
1592 Synthesis and Spectral Properties of Novel C60 Derivative/Ag Nanocomposites
ZHA Qing-qing,WEI Xian-wen*
DOI: 10.3964/j.issn.1000-0593.2008.07.053
The studies on the synthesis and properties of fullerene derivatives had been an active topic in the fullerene chemistry. So synthesis of novel fullerene derivatives and their assembly with functional nanoparticles are very meaningful. In this paper a new bipyridine-substituted [60]fullerene derivative N-methyl-2-[4′-(4″-methyl-2′,2″-bipyridinyl)]-3,4- [60]fulleropyrrolidine (C60BPY) was synthesized by a 1,3-dipolar cycloaddition reaction with C60, 4-methyl-2,2′-bipyridine-4′-carbaldehyde and Sarcosine. Well-fined C60BPY/Ag nanoparticles and nanostructure film were prepared by reduction method using NaBH4 as reagent and self-assembly approach with silver colloid, respectively. Transmission electronic microscope images showed that the diameters of two hybrid structures were about 30-45 nm and 40-55 nm, respectively. The nanoparticles were regular in shape with an uniform size distribution. The results indicated that C60BPY molecule could effectively control the growth and aggregation of silver particles, and make them stable and dispersible well during the process of forming C60BPY/Ag nanocomposites. The UV-Visible absorption spectra showed the surface plasma resonance peaks of silver nanoparticles at 430 and 490 nm in the two nanocomposites, respectively. A red shift of the plasma peak with increasing the size of the nanoparticles was also observed. The fluorescence emission peaks of C60BPY at 720 and 805 nm were significantly quenched by the formation of the C60BPY/Ag nanocomposites. Then the mechanism of quenching was discussed. These nanocomposites may have potential applications in optoelectrionic devices, sensors and catalysis.
2008 Vol. 28 (07): 1592-1595 [Abstract] ( 272 ) PDF (1586 KB)  ( 571 )
1596 Studied on the Determination of Protein by Probe of Zinc 5-Aminosalicylate
CUI Feng-ling,QIN Li-xia,HAO Er-jun,WANG Jun-li,WANG Li,ZHANG Qiang-zhai
DOI: 10.3964/j.issn.1000-0593.2008.07.033
Zinc 5- aminosalylicylate(5-ASZ), a new creative medicine, can react with serum albumin to form a complex. Based on this, a new method for the determination of proteins by synchronous fluorescence spectra under simulated physiological conditions was established using 5 - ASZ as a fluorescence probe. The spectral characterization and intensity of synchronous fluorescence were related to the value of Δλ, reaction medium and reaction temperature, and so on. On basis of these, eperimental results show that, under the optimum conditions, the synchronous fluorescence intensity of the system is in proportion to the concentration of protein in the range of 1.66-496.8 μg·mL-1 for human serum albumin (HSA). The detection limit was 0.88 μg·mL-1 (n=11) for HSA. On basis of these it had been applied to the determination of proteins in human serum, urine and spit samples with satisfactory results,the recovery was within the range of 98.0%-103.8%. Results suggested that the method possessed easy of implementation, rapidity, high sensitivity, broad linear range, and better RSD and recovery, and so on, and the method was employed directly to determine the total proteins in samples, which results were satisfactory.
2008 Vol. 28 (07): 1596-1599 [Abstract] ( 1204 ) PDF (1147 KB)  ( 1229 )
1600 Study on the Mechanism of Energy Transfer between Fluorescein Sodium and Tetrabromofluorescein Sodium in Micelles of Cationic Surface Active Agent
LIU Bao-sheng,ZHANG Yan-qing,WANG Yun-ke, Lǖ Yun-kai
DOI: 10.3964/j.issn.1000-0593.2008.07.030
In the present paper, the fluorescence reaction of cationic surface-active agents (CSAA) with Tetrabromofluorescein sodium (TBF) in aqueous solution was investigated. It was found that the fluorescence quenching of TBF appears when it reacts with the cation monomer of a CSAA and a new stronger fluorescence is obtained when the ion-associates react with the micellate of CSAA. The authors investigated the condition of energy transfer between acidic fluorescent dyes in micelles of cetyl trimethyl ammonium bromide or hexadecyl pyridinium bromide. It was indicated that in the micelles formed by cationic surface active agent with dyes embedded (cationic surface active agent and dyes are charge opposite), the effective energy transfer between anionic dyes could occur. When the concentration of cationic surface active agent reached certain value, the energy transfer could occur. With the value of two thirds of critical micelle concentration, the efficiency of energy transfer reached the maximum; when the concentration of cationic surface active agent increased, the efficiency of energy transfer would be decreased. The authors also deduced the model of energy transfer between dyes in micelles and laws of it.
2008 Vol. 28 (07): 1600-1602 [Abstract] ( 213 ) PDF (1346 KB)  ( 631 )
1603 Study of Applying Fluorescence Spectrum Imaging to Quantitative Assay of Proteins in Bio-Chip
CHAO Ke-fu1,2,ZHANG You-lin1,KONG Xiang-gui1*,LI Bing1,ZENG Qing-hui1,SONG Kai1,2,SUN Ya-juan1
DOI: 10.3964/j.issn.1000-0593.2008.07.049
In the present work, the amount and the activity of the goat anti-human IgG, to bind the human IgG labelled with fluorescein isothiocyanate (FITC), immobilized on silicon surfaces modified with APTES and APTES-Glu, respectively, were studied using the fluorescence spectrum imaging(FSI), the results of which were compared with that of ellipsometry. It is shown that the amount of the human IgG labeled with FITC on APTES-Glu measured using FSI is 2.8 times higher than that on APTES, which is nearly coincident with the 2.2 times obtained using ellipsometry, showing that the activity of the goat anti-human IgG on APTES-Glu is higher than that on APTES. It is reasoned that the FSI is used in the fluorescence immunoassay the for measurement of quasi-quantification or quantification.
2008 Vol. 28 (07): 1603-1607 [Abstract] ( 1801 ) PDF (1555 KB)  ( 685 )
1608 Phosphorescent Effect of Ir(ppy)3 on the Luminescent Characteristic of Rubrene
XU Hong-hua1,2,XU Zheng1,ZHANG Fu-jun1,ZHAO Su-ling1,YUAN Guang-cai1,CHEN Yue-ning2
DOI: 10.3964/j.issn.1000-0593.2008.07.055
Many organic matters including heavy metal ions can validly utilize the singlet and triplet for luminescence owiog to the spin-orbit coupling. As a result, the internal quantum efficiency can easily achieve a value higher than traditional organic light emitting diodes in theory. There is a strong luminescence of PVK in PVK:PBD:Rubrene system. PL spectra excited by 345 nm of PVK:PBD:Rubrene thin film has a 410 nm PVK luminescent peak and a 560 nm Rubrene peak. EL still has a PVK luminescent peak, which should be kept from happening. Excitons can not adequately transferred from the matrix solution to Rubrene. The doping with Ir(ppy)3 improves the PVK:PBD:Rubrene system performance. PL spectra excited by 345 nm of PVK:PBD:Ir(ppy)3:Rubrene with low concentration of Rubrene has a 510 nm Ir(ppy)3 peak and a new 548 nm one. However, the Ir(ppy)3 peak is smaller and the Rubrene one is bigger in EL spectra. Notably a strong and single luminescence of Rubrene is obtained in EL and PL spectra excited by 345 nm of PVK:PBD:Ir(ppy)3:Rubrene with high concentration of Rubrene. Meanwhile, the Ir(ppy)3 luminescent peak disappears. The mechanism originates from the phosphorescent effect of Ir(ppy)3. The singlet excitons can basically be transferred from PVK:PBD or Ir(ppy)3 to Rubrene. But most excitons from Ir(ppy)3 can directly tunnel to the fluorescent material and come into being singlet states that can return to ground states and cause luminescence. Rubrene can accept proportional excitons with low concentration. While the concentration of Rubrene is higher, excitons can be entirely accepted by Rubrene. The effect also restricts the luminescent intensity of Ir(ppy)3 and boosts up that of Rubrene. Furthermore, the energy transfer in PVK:PBD:Ir(ppy)3:Rubrene system is primary the Forester energy transfer. Excitation spectra of Rubrene and emission spectra of Ir(ppy)3 have a large overlap revealing that there is a strong energy transfer and further confirmed the phosphorescent effect of Ir(ppy)3. The doping system with phosphorescence material and small molecules can enhance the brightness and internal quantum efficiency.
2008 Vol. 28 (07): 1608-1611 [Abstract] ( 201 ) PDF (1497 KB)  ( 604 )
1612 Investigation of Interaction between Levofloxacin and Bovine Serum Albumin by Fluorescence Analysis Based on Liquid Drop
CHEN Ze-zhong, FENG Feng*,YANG Wen-juan,LIANG Wen-juan,LI Ren-jun,WANG Cheng
DOI: 10.3964/j.issn.1000-0593.2008.07.031
The interaction between pharmaceutical and protein is an important pharmacokinetic characteristic. Most kinds of drugs must reach the receptor to perform the pharmacological function by plasma. Albumins can serve as a depot protein and a transport protein for numerous endogenous and exogenous compounds. It is of great significance to investigate the binding interaction between albumin and drugs, since it can not only help understand the transportation and distribution of drugs but also elucidate the mechanism. Under the physiological condition of body, the interaction between levofloxacin (LVFX) and bovine serum albumin (BAS) was investigated by fluorescence spectra and ultraviolet absorbance (UV) spectra based on liquid drop. The experimental results showed that LVFX quenches the fluorescence of BAS by forming a LVFX-BSA complex. According to Lineweaver-Burk equation, the apparent binding constants (KLB) between LVFX and BSA were 1.694 9×105 L·mol-1 (291 K) and 2.881 0×105 L·mol-1 (310 K), and the binding sites (n) were 0.884 9 (291 K) and 0.808 9 (310 K). Thermodynamic parameters could be evaluated from the thermodynamic second law, with ΔΗ (enthalpy) being 20.94 kJ·mol-1 and ΔS (entropy) being 172.1 J·mol-1. According to the relation between thermodynamic parameters and the interaction force, LVFX depended principally on the hydrophobic interaction to bind with BSA. The results showed that the quenching belonged to static fluorescence quenching with non-radiation energy transfer happening within single molecule. The binding locality was an area 2.68 nm away from tryptonphan residue-212 in BAS according to Frster’s non-radiation energy transfer mechanism. The conformational changes of BSA were evaluated by measuring the synchronous fluorescence intensity of protein amino acid residues, both before and after the addition of LVFX. A slightly stronger blue-shift of tryptophan fluorescence upon the addition of drug was observed, and the emission maximum of tyrosine kept its position. It was suggested that the environments of tryptophan residues in pure albumin solution are relatively polar. Binding of LVFX changes the environments to apolar ones. The shift in polarity is brought about by confirmation changes due to the interaction between albumin and ligand molecule.
2008 Vol. 28 (07): 1612-1616 [Abstract] ( 217 ) PDF (1323 KB)  ( 599 )
1617 Synthesis of New Blue Pyrazoline Fluorescent Compounds and Study of Infrared Spectroscopy
XIAN Yuan-fang1,LI Dong-feng2,WANG Yu-ming1
DOI: 10.3964/j.issn.1000-0593.2008.07.034
According to Schellhammer theory of the relation between chemical structure and fluorescent quality, and referring to the synthesized benzothiazolyl pyrazoline compounds, the authors designed 1-benzimidazolyl or 1-benzothiazolyl, 3-phenylic derivatives, which posses fluorescent property. The authors introduced 5-phenyl as auxochrome group which can make fluorescence spectrum bathochromic. If there were —NH2 in the benzene ring, the fluorescence would be increased. Two kinds of benzimidazolyl and benzothiazolyl compounds with —NH2 were synthesized which were not reported. The determination of fluorescence proved that its fluorescence strength is better. The fluorescence emission wavelength is in the region of green-blue light, and there are two kinds of blue light fluorescence compounds. All these compounds were characterized by elemental analysis and infrared spectroscopy. The characteristic peaks of the absorption spectra of these compounds were found by IR spectral analysis. The compound structure was determined.
2008 Vol. 28 (07): 1617-1620 [Abstract] ( 1917 ) PDF (1136 KB)  ( 714 )
1621 Development of a Fluorescence Polarization Immunoassay for Sulfamerazine
WANG Zhan-hui,ZHANG Su-xia,SHEN Jian-zhong*
DOI: 10.3964/j.issn.1000-0593.2008.07.035
A fluorescence polarization immunoassay (FPIA) based on a monoclonal antibody for the determination of sulfamera (SMR) was developed. The fluorescein-labeled SMR and sulfamethazine (SMZ) were synthesized and purified by thin layer chromatography (TLC). The optimized SMR FPIA had a dynamic range from 5.4 to 218.8 ng·mL-1 with IC50 value of 23.4 ng·mL-1 and a detection limit of 2.3 ng·mL-1. The specificity of the FPIA for SMR was investigated using other 16 sulfonamides and the cross-reactivity for SMR, SMZ and sulfadiazine (SDZ) was 100%, 25% and 8.6%, respectively.
2008 Vol. 28 (07): 1621-1625 [Abstract] ( 2114 ) PDF (1483 KB)  ( 706 )
1626 Study on the Chinese Medicinal Qingkailing Injections Intermediate by Support Vector Machines and Ultraviolet Spectrometry
ZHU Xiang-rong1,LI Na2,SHI Xin-yuan2,QIAO Yan-jiang2,ZHANG Zhuo-yong1*
DOI: 10.3964/j.issn.1000-0593.2008.07.056
The first derivative and wavelet compression methods were used to eliminate the slope-background and reduce variables for the measured ultraviolet (UV) spectra of Chinese medicinal Qingkailing injections intermediate. Then,support vector machine (SVM) was used for building the classification model to discriminate qualified and unqualified samples. The effects of spectral preprocessing and model parameters were investigated. Under optimized conditions,correct classifications of 100%,95.4%,97.3%,and 100% were obtained for the four batches of the intermediate of Qingkailing injection samples,respectively. A percentage of 97.3% of the intermediate samples were correctly classified for all the four batches of mixture samples. Results showed that SVM technique can be a useful means for quality control of Chinese medicinal injections owing to its good accuracy and better generalization.
2008 Vol. 28 (07): 1626-1629 [Abstract] ( 1834 ) PDF (1350 KB)  ( 664 )
1630 Determination of Polyphenols in Tea by a New Method Spectrophotometry
ZHANG Shu-fang
DOI: 10.3964/j.issn.1000-0593.2008.07.018
The authors developed a method for the determination of tea polyphenols. Phenanthroline is a sensitive regent for the determination of Fe2+, it can react with Fe2+ to form an orange complex in acidic solution. A new spectrophotometric method was proposed for the determination of tea polyphenols in tea samples based on that tea polyphenols could react with Fe3+ to produce Fe2+,and the orange complex would be formed by the reaction of Fe2+ with Phenanthroline in acidic solution. In the presence of positive iron surfactant CTMAB, the sensitivity of chromogenic reaction was improved.The work focused on the optimizing of experiment conditions such as wavelength of determination, buffer solution, surfactant, and the react time etc. At the maximum absorption wavelength of 510 nm, the apparent molar absorptivity was 0.88×105 L·mol-1·cm-1,Beer’s law was obeyed in the range of 4.00 to 32.00 μg·mL-1 Polyphenols. The detection limit was 2.0 μg·mL-1. This method was applied to the determination of polyphenols in tea samples with satisfactory results. The method has three merits, namely high level of accuracy and sensitivity, simplicity, and simple equipment.
2008 Vol. 28 (07): 1630-1632 [Abstract] ( 1436 ) PDF (913 KB)  ( 1797 )
1633 Determination of Total Flavones from Euonymus Alatus Sieb by Microwave-Assisted Extraction and Absorption Spectroscopy
ZHANG Fan1,ZHOU Feng1,WANG Gui-hua1,YANG Yi1*,GUO Zhen-ku2
DOI: 10.3964/j.issn.1000-0593.2008.07.006
Determination of total flavones from euonymus alatus sieb by microwave-assisted extraction and absorption spectroscopy was reported. The effects of solvent concentration, ratio of solution to solid, microwave power and radiation time were evaluated by single factor and orthogonal experiments. The extraction conditions of flavones from euonymus alatus sieb by microwave-assisted method were optimized as 40:1 of the weight ratio of 60% (V/V) ethanol to twigs and microwave power of 255 W for 5 min. Under the optimized conditions the relative standard deviation is 1.71% (n=5) and the recovery is 97%-101%. Compared with Soxhlet extraction and ultrasound-assisted extraction, microwave-assisted extraction was simple and accurate with good reproducibility. It is suitable for the determination of flavone in many kinds of traditional Chinese medicines.
2008 Vol. 28 (07): 1633-1636 [Abstract] ( 1424 ) PDF (1185 KB)  ( 602 )
1637 Resonance Scattering Spectra of Apolipoprotein Immunocomplex Particles and Its Analytical Application
SUN Shuang-jiao1, 3,LIANG Ai-hui2,JIANG Zhi-liang1*,CHEN Bin1
DOI: 10.3964/j.issn.1000-0593.2008.07.011
In pH 6.8 Na2HPO4-NaH2PO4 buffer solution and in presence of polyethylene glycol(PEG), apolipoprotein AI (ApoAI) and apolipoprotein B (ApoB) would combine with their corresponding antibody and produced immune complex particles in size of about 180 nm and 140 nm respectively, which exhibit stronger resonance scattering (RS) effect at 340 nm and 470 nm. The influence of pH, antisera volume, PEG concentration, incubation time and co-exists substances was considered. Under the optimal conditions, the RS intensity is proportional to the concentrations of ApoAI and ApoB when their concentration is in the range of 8.4-430.0 ng·mL-1 and 14.8-590.0 ng·mL-1, respectively. The detection limits (DL) are 6.2 ng·mL-1 for ApoAI and 7.0 ng·mL-1 for ApoB. The method was successfully applied to determination of ApoAI and ApoB in human serum samples, with satisfactory results.
2008 Vol. 28 (07): 1637-1640 [Abstract] ( 1266 ) PDF (1198 KB)  ( 681 )
1641 Application of Atomic Emission Spectroscopy Analysis in the Atmospheric Pressure Plasma Polishing Process Study
WANG Bo,ZHANG Ju-fan*,DONG Shen
DOI: 10.3964/j.issn.1000-0593.2008.07.013
The atmospheric pressure plasma polishing (APPP) is a novel precision machining technology. It performs the atom scale material removal based on low temperature plasma chemical reactions. As the machining process is chemical in nature, it avoids the surface/subsurface defects usually formed in conventional mechanical machining processes. APPP firstly introduces a capacitance coupled radio frequency (RF) plasma torch to generate reactive plasma and excite chemical reactions further. The removal process is a complicated integrating action which tends to be affected by many factors, such as the gas ratio, the RF power and so on. Therefore, to improve the machining quality, all the aspects should be considered and studied, to establish the foundation for further model building and theoretical analysis. The atomic emission spectroscopy analysis was used to study the process characteristics. A commercial micro spectrometer was used to collect the spectrograms under different parameters, by comparing which the influence of the RF power and gas ratio was initially studied. The analysis results indicate that an increase in RF power results in a higher removal rate within a certain range. The gas ratio doesn’t show obvious influence on the removal rate and surface roughness in initial experiments, but the element compositions detected by X-ray photoelectron spectroscopy technology on the machined surfaces under different ratios really indicate distinct difference. Then the theoretical analysis revealed the corresponding electron transition orbits of the excited reactive fluorine atoms, which is necessary for further mechanism research and apparatus improvement. Then the initial process optimization was made based on the analysis results, by which the Ra 0.6 nm surface roughness and 32 mm3·min-1 removal rate were achieved on silicon wafers.
2008 Vol. 28 (07): 1641-1644 [Abstract] ( 1752 ) PDF (1383 KB)  ( 737 )
1645 Determination of Inorganic Elements in Five Kinds of Mongolia Medicines by High Pressure Sealed Microwave Digestion-ICP-AES
Sagara,Zhaorigetu,DONG Guo-liang,ZHANG Jing-xia
DOI: 10.3964/j.issn.1000-0593.2008.07.010
Five kinds of Mongolia medicines, Eridun-Urile, Deduhonghuaqiweiwan, Tonglage-5, Uzhumu-7 and Geiwang-9 are digested with HNO3-HClO4 system by high pressure system-sealed Microwave Digestion. The 17 inorganic elements content of magnesium, aluminum, calcium, chromium, manganese, ferrum, cobalt, nickel, copper, zincum, arsenic, selenium, strontium, molybdenum, silver, cadmium, plumbum in the solution are determined by ICP-AES. The results are proved to be reliable by adding standard recovery experiment. The recovery is 97.48%-103.01% for Mg, 102.71%-105.60% for Al, 102.00%-105.53% for Ca, 98.78%-100.34% for Cr, 101.93%-104.65% for Mn, 100.34%-104.51% for Fe, 103.13%-105.46% for Co, 100.07%-103.22% for Ni, 97.25%-99.06% for Cu, 98.57%-100.10% for Zn, 102.35%-105.37% for As, 100.24%-104.59% for Se, 99.19%-102.70% for Sr, 103.35%-105.78% for Mo, 99.65%-101.32% for Ag, 102.73%-105.32% for Cd, and 104.76%-106.35% for Pb by this method. The relative standard deviation is less than 3.3% for all the elements. And the method has high accuracy and good precision. The determination results indicate that the content of element in Five Kinds of Mongolia Medicines is 0-15 μg·g-1 for Cd, Ag, As, Pb, Co, Ni, Cu; 15-100 μg·g-1 for Mo, Se, Zn, Cr; 100-3 000 μg·g-1 for Mn, Sr, Fe, Mg, Al; 3 000-8 000 μg·g-1 for Ca. Among of the five kinds of mongolia medicines, the content of elements has great differences. The order is Ca>Mg>Al>Fe>Mn>Sr>Se>Zn>Mo>Cu>Pb>As>Cr>Ni>Co>Cd>Ag for Eridun-Urile; Ca>Al>Fe>Mg>Mn>Sr>Se>Mo>Zn>Ni>Cr>Cu>Pb>As>Co>Cd>Ag for Deduhonghuaqiweiwan; Ca>Fe>Mg>Al>Mn>Sr>Se>Zn>Mo>Cr>Ni>Cu>Pb>As>Co>Cd>Ag for Tonglage-5, Ca>Al>Mg>Fe>Sr>Mn>Se>Zn>Co>Mo>Cr>Cu>Pb>As>Ag>Ni>Cd for Uzhumu-7 and Mg>Ca>Al>Fe>Se>Mn>Zn>Sr>Mo>Cu>Cr>Pb>As>Ag>Co=Cd=Ni for Geiwang-9. The content of common elements Ca, Mg, Fe, Mn, Zn, Cu are higher. These results provide theoretical basis for developing quality control, improving the potency of Mongolia medicines and developing new Mongolia medicines.
2008 Vol. 28 (07): 1645-1649 [Abstract] ( 613 ) PDF (998 KB)  ( 626 )
1650 Determination of Rhenium in Raffinate and Residue from Synthesis of Methyltrioxorhenium by ICP-AES
LIU Ning1,ZHANG Shi-tao2,LI Jun1,YUE Shuang3,ZANG Shu-liang3*
DOI: 10.3964/j.issn.1000-0593.2008.07.009
Methyltrioxorhenium is a novel and efficient organometallic catalyst. It has exhibited amazingly high activities in a variety of organic reactions, and can form compounds with Lewis base. Thus, the improvement of its synthesis rate has become a pop topic all over the world. The content of rhenium in raffinate and residue from the synthesis of methyltrioxorhenium is an important standard for the evaluation of synthesis rate and a foundation for the optimization of synthesis condition. UV spectrophotometry is the standard technique for the determination of rhenium. However, this method presents several disadvantanges such as low sensitivity, high interferences, and hard handling. Inductive coupled plasma-atomic emission spectrometry has many advantages such as high precision, rapid analysis speed and good stability, and can determine multi-elements simultaneously. It is widely used in determination in every walk of life. An ICP-AES method for determination of the content of rhenium in raffinate and residue from the synthesis of methyltrioxorhenium was used. The working parameters were optimized. The detection limit was 0.01 mg·L-1. RSD was in the range of 0.48%-1.12% and recoveries in the range from 97.2%-104% were obtained. The spectrum interference can be neglected. Compared with spectrophotometer, the proposed method was proved to be simple, rapid and accurate, and the result was satisfactory.
2008 Vol. 28 (07): 1650-1652 [Abstract] ( 2049 ) PDF (959 KB)  ( 616 )
1653 Studies on Contents of Arsenic, Selenium, Mercury and Bismuth in Tea Samples Collected from Different Regions by Atomic Fluorescence Spectrometry
WANG Xiao-ping,MA Yi-jin,XU Yuan-chun
DOI: 10.3964/j.issn.1000-0593.2008.07.014
After microwave or wet decomposition, the contents of arsenic, selenium, mercury and bismuth in twenty-one Chinese tea samples and five Japanese tea samples were determined by atomic fluorescence spectrometry, and plant standard reference materials were used to verify the accuracy and the precision of the analytical method. Moreover, the contents of these four elements were also determined in different parts of tea sapling sampled from the suburbs of Suzhou, a place famous for its Chinese tea biluochun. It was shown that microwave decomposition is indispensable for getting good results of mercury contents in tea samples by AFS. Compared with those in Japanese tea samples, the contents of arsenic, selenium, mercury and bismuth in Chinese tea samples are significantly high, but the Chinese tea sample produced in Hunan province has the lowest bismuth content. Arsenic, selenium and mercury are mainly present in the bark, the root and the old leaves of tea sapling, nevertheless, the bismuth contents in the root and the bark-deprived trunk are so low that they can not be determined accurately. From this study, a preliminary conclusion can be drawn that tea is not a selenium-accumulating plant and the great majority of selenium in Chinese tea samples originates from the dry and wet deposition of atmospheric aerosols.
2008 Vol. 28 (07): 1653-1657 [Abstract] ( 2443 ) PDF (949 KB)  ( 646 )
1658 Study on Lead Absorption in Pumpkin by Atomic Absorption Spectrophotometry
LI Zhen-xia, SUN Yong-dong, CHEN Bi-hua, LI Xin-zheng
DOI: 10.3964/j.issn.1000-0593.2008.07.024
A study was carried out on the characteristic of lead absorption in pumpkin via atomic absorption spectrophotometer. The results showed that lead absorption amount in pumpkin increased with time, but the absorption rate decreased with time; And the lead absorption amount reached the peak in pH 7. Lead and cadmium have similar characteristic of absorption in pumpkin.
2008 Vol. 28 (07): 1658-1660 [Abstract] ( 2964 ) PDF (1154 KB)  ( 1422 )
1661 Mineralogical Effect Correction for Pressed Iron Ore Samples in Wavelength Dispersive X-Ray Fluorescence Analysis
SHAN Hua-zhen,ZHUO Shang-jun*,SHENG Cheng,SHEN Ru-xiang
DOI: 10.3964/j.issn.1000-0593.2008.07.007
The possibility of correcting mineralogical effect for pressed powder pellets of iron ore samples was studied in wavelength dispersive X-ray fluorescence analysis of major and minor elements with 10 Chinese iron ore CRMs. Two methods were applied to reduce the influence of mineralogical effect. The first one is to check 2θ angles for every sample before measurement to correct peak shift; another method is replacing peak intensity with peak area of the analytical line to correct the shape distortion of the spectrum. The K factors of the two methods for each element were compared to those from regular measurements. The results show that the calibration for most of the elements was improved, although to different degrees. The improvement in the calibration for sulfur is evident. The calibration for other elements can meet the general requirements except for total iron.
2008 Vol. 28 (07): 1661-1664 [Abstract] ( 2022 ) PDF (995 KB)  ( 739 )
1665 Spectroscopic Characterization and Properties of Mg2B2O5w/AZ91D Magnesium Composites
JIN Pei-peng1,2,DING Yu-tian1,XU Guang-ji1, LIU Yan2
DOI: 10.3964/j.issn.1000-0593.2008.07.012
Magnesium borate whisker (Mg2B2O5w) reinforced Mg matrix composite was fabricated by vacuum-gas pressure infiltration process. The Mg2B2O5 w preforms forming process was determined. The Mg2B2O5 whiskers were fabricated into a preform by wet forming method without any binder. The Vacuum-Gas Pressure Infiltration process and parameters are also developed. The micrographs revealed reasonably uniform distribution and random orientation of the whiskers in the as-cast Mg2B2O5w/AZ91D composite and the composites were without pores defect. The phases were analyzed by XRD patterns for the as-received whiskers, the whiskers sintered at 1 000 ℃ for 3 h and the as-cast composite, respectively. Then, the microstructure evolution of the composite was investigated when the composite was heat-treated. Meanwhile, the relationships between microstructure and micro- hardness of the alloy heat-treated were also studied. The heat-treatment condition were solution at 415 ℃ for 8 and 24 h, respectively, aging treatment at 200 ℃ for 8, 12, 16, 20 and 24 h, respectively and solution at 415 ℃ for 8 or 24 h and subsequent aging treated for 8, 12, 16, 20, 24 h, respectively. The phases were analyzed by XRD patterns for the composites after different heat treated process. The results of XRD patterns were shown to be in good agreement with the microstructures evolution of the composites. The results showed that the micro-hardness of the solution treated composites is decreased due to resolution of eutectic phase, whereas the micro -hardness of the aged composites was increased gradually and the peak hardness is reached to 201 HV in the composite aged for 16 hours. Solution treatment at 415 ℃ for 24 h, the β-Mg17Al12 phase is dissolved in the α-Mg phase to form oversaturated solid-solution in the composite and then the diffusive β phase precipitates after subsequent aging treatment at 200 ℃ for 8 h; hence the micro-hardness of the composite was increased 30%. However, as the aging time increased to 24 h, the hardness of the composite was reduced to 183 HV because the β-Mg17Al12 phase precipitate changed from continuous fine platelets to discontinuous coarse platelets. It was concluded that the process of solution at 415 ℃ for 24 h and subsequent aging treatment at 200 ℃ for 8 h was the best process for the composite.
2008 Vol. 28 (07): 1665-1669 [Abstract] ( 571 ) PDF (2785 KB)  ( 668 )
1670 Design of Flat Field Holographic Concave Grating for Near-Infrared Spectrophotometer
XIANG Xian-yi,WEN Zhi-yu
DOI: 10.3964/j.issn.1000-0593.2008.07.028
Near-infrared spectrum analysis can be used to determine the nature or test quantitatively some chemical compositions by detecting molecular double frequency and multiple frequency absorption. It has been used in agriculture,biology, petrifaction, foodstuff, medicament, spinning and other fields. Near-infrared spectrophotometer is the main apparatus for near-infrared spectrum analysis, and the grating is the most important part of the apparatus. Based on holographic concave grating theory and optic design software CODE V, a flat field holographic concave grating for near-infrared spectrophotometer was designed from primary structure, which relied on global optimization of the software. The contradiction between wide spectrum bound and limited spectrum extension was resolved, aberrations were reduced successfully, spectrum information was utilized fully, and the optic structure of spectrometer was highly efficient. Using CODE V software, complex high-order aberration equations need not be solved, the result can be evaluated quickly, flat field and resolving power can be kept in balance, and the work efficiency is also enhanced. A paradigm of flat field holographic concave grating is given, it works between 900 nm to 1 700 nm, the diameter of the concave grating is 25 mm, and F/# is 1.5. The design result was analyzed and evaluated. It was showed that if the slit source, whose width is 50 μm, is used to reconstruction, the theoretic resolution capacity is better than 6.3 nm.
2008 Vol. 28 (07): 1670-1673 [Abstract] ( 264 ) PDF (2353 KB)  ( 660 )
1674 Numerical Simulation and Experimental Demonstration of Error Compensation between Recording Structure and Use Structure of Flat-Field Holographic Concave Gratings
ZHOU Qian,ZENG Li-jiang,LI Li-feng
DOI: 10.3964/j.issn.1000-0593.2008.07.008
A flat-field holographic concave grating can be the only optical element in a spectrometer. If the mutually compensating roles of the concave grating and the spectrometer are taken into account, the difficulty of fabricating concave grating can be reduced. When the holographic method is used to make concave gratings, it is very difficult to fix precisely the spatial distances between the two recording points and the vertex of concave gratings. In like manner, it is also difficult to fix precisely the location of the entrance slit or the CCD in using concave gratings in spectrometers. In other words, during the fabrication stage and the end-use stage of concave gratings, there are inevitable errors between the practical system structure parameters and the theoretical ones. The authors name them fabrication structure errors and end-use structure errors, respectively. Numerical simulation indicates that these two classes of errors will seriously deteriorate the spectral image quality. At present, there are few references describing the elimination of the fabrication and end-use errors of concave gratings. In this paper, a concave grating used in a compact chromatograph is analyzed as an example. By performing numerical simulations that take both fabrication structure parameters and end-use structure parameters into consideration, we found that in a large neighborhood around the design point, the two sets of parameters can mutually compensate. This means that even both sets are away from the optimized design points, as long as proper compensations are made, the spectral image quality of the spectrometer can be as good as designed. In other words, on the one hand, for a specific concave grating that has been made with some fabrication structure errors, we can move the CCD to find an appropriate location where the spectral image quality is as good as designed; On the other hand, for a decided end-use system which has some end-use structure errors, we can adjust the fabrication structure to make concave gratings that will generate good spectral images in this end-use system. The experiment results show that this method is an effective way to adjust the optical system for grating fabrication. The authors also give experimental results that agree with simulation results. Such compensation can reduce both the alignment difficulty and the required precision of fabrication structure parameters of concave gratings. It could also give theoretical guidance to the design and assembly of spectrometers.
2008 Vol. 28 (07): 1674-1678 [Abstract] ( 243 ) PDF (1429 KB)  ( 682 )
1679 Study of In-Situ Measurement System for Porous Alumina Film Based on AFM and Reflectometric Interference Spectroscopy
LIU Chao,ZHANG Dong-xian*,ZHANG Hai-jun
DOI: 10.3964/j.issn.1000-0593.2008.07.025
An in-situ measurement system for porous alumina (PA) film based on atomic force microscope (AFM) in liquid and reflectometric interference spectroscopy (RIFS) was developed. The present article briefly discusses the principle and structure of the system, and introduces its unique characteristic. The system consists of probe unit, XY scanner, Z-piezo feedback system, computer and software, fiber optic spectrometer, anodization control circuitry etc. When a white light beam illuminates the surface of the film, the reflective light beams at the front and back side of the layer are coherent, and lead to periodical amplifications and extinction in the reflective spectrum with the information of the optical thickness of the film. A fiber optic spectrometer was applied in the system which input the refractive spectrum into the computer by which the optical thickness of the film was calculated. Meanwhile according to the surface topography of PA films by AFM in liquid, the effective refractive index was calculated based on Maxwell-Garnett theory and coherent potential approximation (CPA). So the thickness of PA films could be gained at last. To checkout the feasibility and stability of the system, the real-time scanning and thickness measurement experiments were done during anodization of Al sheets in oxalic acid aqueous solution. In the experiment, the authors used 25 mm diameter aluminum (Al) sheets with 99.999% purity and 0.4 mm thickness as the anode, and graphite rod as the cathode. The pretreatment-cleaned Al sheets were anodized in an aqueous solution of 0.5 mol·L-1 oxalic acid at the constant temperature (20±0.2) ℃ with 20 mA·cm-2 anodization electronic current density. Real-time AFM images of PA film were successfully obtained during anodization. The pore-ratios of Al sheet were 7.81% and 13.83% at oxidizing time 150 min and 180 min respectively. Correspondingly, the effective indexes were calculated to be 1.62 and 1.60, respectively. Combining the reflective spectrum gained by the fiber optic spectrometer, the wave number differences between the two adjacent extrema were 57.69 mm-1 and 50.00 mm-1. Based on reflectometric interference spectroscopy, the thickness of PA films was found to be 5.35 and 6.25 μm with oxidizing time 150 min and 180 min respectively. The system has characteristics of convenient manipulation, non-destructive and high-resolution in-situ measurement. And the surface morphology, pore-ratio and effective refractive index can also be gained at the same time.
2008 Vol. 28 (07): 1679-1683 [Abstract] ( 1851 ) PDF (1485 KB)  ( 686 )
1684 Experiments of Micro-Distance Measurement for GMLM with Spectrum Analysis Method
ZHANG Jie,HUANG Shang-lian,ZHANG Zhi-hai,SUN Ji-yong,SHI Ling-na,ZHU Yong
DOI: 10.3964/j.issn.1000-0593.2008.07.026
Projection display devices are undergoing a period of multi-development, and with the maturation of MEMS technology, which leads to MEMS-based light modulators for display applications, have become one of the research focuses. The structure of MEMS-based grating moving light modulator (GMLM) is composed of the reflection plate, address electrode and four cantilevers, and movable grating plate, which is supported by four crab-cantilevers placed around, and is actuated like a piston by electrostatic force. The piston-type motion of grating can be used to modulate the phase of incident light. The micro-distance between the upper surface of movable grating and underlying reflector is a key parameter and is important to GMLM performance. Traditional measurement method such as step-machine would destroy the device; while a high accuracy and non-contact measurement machine called KYKO White Light Interferometer is expensive. In the present paper, the GMLM optical principle using scalar diffraction theory was in details analyzed. A novel non-contact wavelength scanning spectrum analysis method was put forward to measure the distance between the upper surface of movable grating and underlying reflector. The U-4100 spectrophotometer was adopted to gain spectrum information; while the spectrum analysis method using peak wavelength position was introduced to calculate the micro distance. The measurement result is consistent to theoretical result. The micro-distance is 1.131 3 μm using such non-contact wavelength scanning spectrum analysis method, while it is 1.240 0 μm with WYKO White Light Interferometer. The relative error was lower than 1%, compared with the results measured by WYKO White Light Interferometer, and the method has good repetition ability and is cheap with RMB50 Yuan each time. Furthermore, measuring pull-in voltage, resonance frequency and micro distance in MEMS-based diffraction and interference devices was proposed completely based on such non-contact wavelength scanning spectrum analysis method.
2008 Vol. 28 (07): 1684-1688 [Abstract] ( 1943 ) PDF (1852 KB)  ( 556 )
1689 Influence of Polarization Maintaining Fibers and Polarizer on the Lightwave Spectrum
ZHANG Chun-xi,LI Yan*,XU Hong-jie,FENG Li-shuang,LIANG Sheng
DOI: 10.3964/j.issn.1000-0593.2008.07.029
The parameters of polarization maintaining fibers and polarizer, and the splicing angles between them have important influence on the spectral characteristics of lightwave propagating in them. The transmission model of lightwave was established using Jones matrix. For the first time, the effect of degree of polarization, fiber lengths, splicing angles between fibers and between fiber and component on the output spectrum was discussed. It was indicated that the shape of output spectrum of the unpolarized lightwave will not change when the splicing angles between fibers and between fiber and component were not zero, while there were periodical functions added to the output spectrum of polarized of partially polarized lightwave. The result that when the angles were constants, the longer the fibers were, the smaller the periods of periodical functions, and that when the fiber lengths were constants, in a certain range the bigger the angles, the larger the amplitudes of periodical functions, was achieved. The conclusions were verified by experiments and they could supply theoretical guidance for the systems using polarization maintaining fibers and polarizer.
2008 Vol. 28 (07): 1689-1694 [Abstract] ( 2514 ) PDF (1608 KB)  ( 566 )