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2006 Vol. 26, No. 02
Published: 2006-02-26

 
       光谱学与光谱分析
193 Application of Two-Photon Excitation Fluorescence Imaging to Real-Time Investigation of Mouse Preimplantation Embryo
CHENG Bing, LIN Dan-ying, WANG Xiao-guang, CHEN Die-yan, MA Wan-yun*
The blue shift of a two-photon excitation absorption peak allows the application of a single wavelength to the simultaneous excitation of several fluorochromes with disparate emission characteristics. An output at 730nm of a mode-locked femtosecond Ti-sapphire laser was used to excite four different commonly used fluorochromes, namely Hoechst 33342, Fluo-4, PI and Indo-1, and characteristic fluorescence images were obtained using (455±15)nm, (540±15)nm, (580±16)nm and (500±15)nm filters respectively. An approach to exciting with a single wavelength, staining with two different fluorochromes, and collecting fluorescence in two separate channels was employed to study mouse preimplantation embryos by 3D and 4D real-time imaging. Combined with the merits of two-photon excitation fluorescence imaging, such as better penetration, less photon-damage, and higher signal-to-noise ratio, this approach was supposed to be a novel multi-parameter investigating tool for mouse preimplantation embryos development study.
2006 Vol. 26 (02): 193-197 [Abstract] ( 1778 ) PDF (789 KB)  ( 752 )
198 Laser Abduction Fluorescence Spectrum for Aerosol Particle Measurement
LIAN Yue1, LIU Wen-qing1, LU Jian-chun2, LIU Jian-guo1, ZHANG Tian-shu1
The present article describes a method to measure fluorescence characteristics of aerosol particles in air, and a technique used to measure the aerodynamic diameter of aerosol particles. Experiment system design details and measurement plans were given. Fluorescence intensity spectra were compared with particle aerodynamic diameter spectra. Aa analysis method of fluorescent percentage, which is useful to identify biological aerosol particles, was also discussed.
2006 Vol. 26 (02): 198-202 [Abstract] ( 1839 ) PDF (615 KB)  ( 716 )
203 Spectroscopic Ellipsometry Investigations of Amorphous Diamond Films Deposited with Filtered Arc
ZHU Jia-qi1, HAN Jie-cai1, TAO Yan-chun2, JIANG Chun-zhu1
In order to investigate thoroughly the optical properties of amorphous diamond (α-D) films deposited by the filtered vacuum arc technology, the optical constants of the films were measured by spectroscopic ellipsometry. Moreover, the dispersion relations of the optical constants, and the correlations among refractive index, extinction coefficient, optical gap and the substrate bias were also analyzed. It has been shown that the refractive index of α-D films is higher than that of diamond crystal, and the absorption edge corresponding to the interband transformation can be described with the parabolic line shape. With increasing the wavelength, the extinction coefficient gradually declines and approaches nearly to zero in the infrared band. In addition, the adjustable amplitudes of the optical constants owing to the changing bias also reduce strikingly with the extension of the wavelength. With raising the bias, the refractive index and the optical gap firstly augment, then minish, and there is a maximal value when the substrate bias is -80 V. However, the extinction coefficient firstly minishes, then augments, and there is a minimal value when the bias is -80 V.
2006 Vol. 26 (02): 203-207 [Abstract] ( 734 ) PDF (599 KB)  ( 736 )
208 The Surface States and the Electron-Hole Pair Recombination of TiO2 Nanopowders
LIU Bao-shun, HE Xin, ZHAO Xiu-jian*, ZHAO Qing-nan
The nanometer TiO2 was prepared by sol-gel method. The structure and composition of the nanometer TiO2 were analyzed in detail by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared spectrometry (FTIR). The UV-visible spectrum and fluorescence spectrum were studied too. The results show that the nanometer TiO2 contains better anatase crystallinity, and the average size of the nanometer TiO2 is about 10 nm. The surface states, Ti—OH and Ti—H2O, are formed on the surface of nanometer TiO2 in aqueous solution because of high absorption ability, whose energy levels are about 0.6 and 0.54 eV above the valence band, respectively. The surface state Ti—H2O is destroyed after heat treatment at 500 ℃ for two hours, but the Ti—OH still exists, and the crystalline lattice presents some oxygen vacancies whose energy level is about 3.13 eV above valence band. For the nanometer TiO2 aqueous solution, the surface recombination of electron-hole pairs via Ti—OH and Ti—H2O is the main recombination manner, but for the samples after heat treatment, direct recombination from conduction band to valence band is the main recombination manner, due to the destroying of surface states, with the companion of indirect recombination via oxygen vacancy and surface recombination via Ti—OH.
2006 Vol. 26 (02): 208-212 [Abstract] ( 546 ) PDF (545 KB)  ( 732 )
213 Highly Sensitive Tunable Diode Laser Absorption Spectroscopy of CO2 around 1.31 μm
SHAO Jie1, 2, GAO Xiao-ming1, 2, YANG Yong2, HUANG Wei2, PEI Shi-xin2, YUAN Yi-qian1, ZHOU Shi-kang2, ZHANG Wei-jun2
Fifteen new absorption lines were observed when studying CO2 absorption spectroscopy by wavelength modulation (WM) technique with a DFB laser. The line intensity we can detect is 2.251 63×10-27 cm-1·(moleculecm-2)-1 at 6.67×10 Pa pressure, corresponding to an absorbance of 3.88×10-8. The overtone spectra of CO2 around 1.31 μm have been measured with a tunable diode laser and the corresponding spectral parameters (positions, intensities, and self-broadening coefficients) are presented.
2006 Vol. 26 (02): 213-217 [Abstract] ( 1883 ) PDF (452 KB)  ( 722 )
218 Effect of Carbon Coating on Radiation Intensity of Laser-Induced Metal Plasmas
CHEN Jin-zhong, LI Hong-yan, WEI Yan-hong, GUO Qing-lin, HUI Su-fang
In order to reduce the reflectance of laser beam on sample surface and enhance the radiation intensities of laser-induced metal plasma, a means has been studied for carbon coating on the surface of steel sample. The experimental results showed that the line intensities of the laser plasma formed when a high-energy neodymium glass laser (~25 J) was used to generate the plasma in air at atmospheric pressure increased by a factor in the range of 10%-28% for the steel sample with the carbon coating. The excitation temperature of laser plasma was measured to explain the mechanism that the line intensities increase. In addition, it was found that the stronger intensity of atomic emission spectrum appeared at the radial location 1 mm in the laser plasma, not at the central place.
2006 Vol. 26 (02): 218-220 [Abstract] ( 743 ) PDF (383 KB)  ( 770 )
221 The Study of Remote Sensing CH4 Concentration Based on Tunable Diode Laser Absorption Spectroscopy
WANG Shi-mei, LIU Wen-qing, LIU Jian-guo, TU Xing-hua, YANG Li-shu
In the present paper, a review and analysis of the theory of direct absorption spectroscopy and modulation spectroscopy using tunable diode laser were provided, and a remote sensing system of CH4 was designed. A near infrared tunable diode laser operating at wavelength 1.65 μm at room temperature was used to perform the measurement of CH4, using the R(6) line of the 2ν3 band of methane. Signal to noise ratio and fundamental noise sources were also discussed. This work has laid the foundation for remote sensing of CH4 on-line.
2006 Vol. 26 (02): 221-224 [Abstract] ( 1750 ) PDF (527 KB)  ( 743 )
225 Study on Micro-Behaviours Shock Ignition for Epoxypropane Using Spectrum Techniques
HU Dong1, 2, WU Jing-he2, YAN Zheng-xin2, LIU Jin-chao2,YUAN Chang-yin1, 3, LI Ping2, CHENG Xin-lu2, SUN Zhu-mei1, 2
The micro-behaviours of shock ignition of epoxypropane were studied by OMA(optical multii channal system) and monochromator techniques. The radicals O, CH2O, C2, CH, CH3O, CO2 and H2O were observed by OMA spectrometer. The delay time and critical condition of shock ignition were determined using three monochromators and gauge. The emergence of intermediate product of O for epoxypropane after shock ignition is always the earliest.
2006 Vol. 26 (02): 225-227 [Abstract] ( 1736 ) PDF (331 KB)  ( 698 )
228 Electron Excitation Temperature of Hexagon Pattern in Argon Discharge at Atmospheric Pressure
LIU Shu-hua, MAO Zhi-guo, LI Shu-feng, RAN Jun-xia, DONG Li-fang*
The emission spectrum and the discharge current waveform of argon dielectric barrier discharge at atmospheric pressure were measured when the filaments self-organized in hexagon pattern by using a specially designed experimental setup. Electron excitation temperature of hexagon pattern was calculated using intensity ratio method. It was found that the electron excitation temperature is higher as the frequency of feeding voltage increases. And the temporal correlation among all micro-discharge channels also becomes higher as the frequency of feeding voltage increases. This work gives useful reference for studying pattern formation dynamics.
2006 Vol. 26 (02): 228-230 [Abstract] ( 1807 ) PDF (350 KB)  ( 748 )
231 Spectrum and Synthesis of Rare Earth Activated Nanoparticle
CHANG Jian-jun1, HUANG Shi-hua1,PENG Hong-shang1, MENG Chun-xia1, YOU Fang-tian1, Lü Shao-zhe2, SUN Ling-dong3
La2O3: Eu3+ nanoparticles were prepared by Gly assistant combustion synthesis with the sizes from 12-28 nm,and a characterization of XRD was done. Spectral properties of the nanoparticles were compared with the bulk. High resolution spectra were measured. Site selective excitation was employed to probe the local environments of Eu3+ ions in La2O3 nanoparticles. The luminescent centers on the surface and the center of the nanoparticles were excited respectively. The spectra were related to surface information. The luminescence from C3v site and the site with lower symmetry on the surface was distinguished.
2006 Vol. 26 (02): 231-234 [Abstract] ( 1296 ) PDF (455 KB)  ( 722 )
235 Spectral Analysis and Photoluminescence Properties of 1,5-Naphthalene Diamine Derivative
LI Jie1, ZHOU He-feng1, HAO Yu-ying2,WANG Hua1, LIU Xu-guang3, XU Bing-she1*
In the present paper, 1,5-bis[N-(1-naphthyl)-N-phenyl] naphthalene diamine(NPN) with high purity was synthesized by liquid-phase Ullmann reaction, and high quality film of NPN was formed on cleaned glass substrates by vacuum evaporation. Photoluminescence properties were studied by solvent effects on UV-Vis absorption spectra and fluorescence spectra. In addition the structure of energy band of NPN was studied by cyclic voltammetry, UV-Vis absorption spectra, and fluorescence spectra. The results indicate that the fluorescence emitting is attributed to the charge transfer transition from nitrogen to aromatic ring. The molecules of NPN in its film form “J-aggregate”. The HOMO energy and optical gap of NPN are -5.74 and 2.79 eV respectively. NPN film could emit intense blue fluorescence with a peak wavelength at 448.6 nm and a bandwidth of 72.6 nm under UV-Vis excitation at 365 nm.
2006 Vol. 26 (02): 235-239 [Abstract] ( 518 ) PDF (615 KB)  ( 727 )
240 The Emission of Organic-Inorganic Single Quantum Well with Organic Heterojunction
QIAN Lei, XU Zheng,TENG Feng, LIU De-ang, QUAN Shan-yu, WANG Yuan-min, WANG Yong-sheng, XU Xu-rong*
Organic-inorganic single quantum well with organic heterojunction ITO\SiO2(60 nm)\MEH-PPV(40 nm)\Alq3(40 nm)\SiO2(60 nm)\Al has been fabricated. With the detailed investigation of photoluminescence and electroluminescence of this novel device, the authors found that the permittivity confinement effect and the quantum size effect have obviously an effect on the optical and electrical properties of organic-inorganic quantum well with organic heterojunction. The electroluminescence of organic-inorganic quantum well with organic heterojunction included three different emissions under alternative-current voltages:410, 510 and 590 nm, which originated from radiative recombination of MEH-PPV, recombination of Alq3 excitons and MEH-PPV excitons respectively.
2006 Vol. 26 (02): 240-243 [Abstract] ( 557 ) PDF (440 KB)  ( 762 )
244 Temperature-Dependent Optical Activity and Birefringence Study of D-Alanine Single Crystal
LI Zong-sheng1,GONG Yan2 ,WANG Wen-qing2,DU Wei-min1*
The measurement of the anisotropy of optical acitivity and birefringence is one of the most important clues to studying physical properties of a biaxial crystal of D-alanine. In order to investigate a second-order phase transition predicted by A. Salam between two states of D-alanine, the behavior of birefringence and optical activity is useful for the phenomenological approach to the transition mechanism. The optical activity as a peculiar quantity can respond to the modulation of the crystal lattice and to the change in the bonding nature of constituent atoms. In the present paper, the authors use the PEM-90 photoelastic modulator to study the conformation change of D-alanine at the temperature ranging from 220 to 290 K. The temperature dependence of I2f/Idc showed that the conformation of D-alanine molecule in single crystal changed around 250 K. The obtained results provide an obvious evidence of optical rotation phase transition predicted by Salam.
2006 Vol. 26 (02): 244-247 [Abstract] ( 1760 ) PDF (408 KB)  ( 739 )
248 Study on the Theory and Experiments of Radiative Parameters of the Eu3+ Ion in Transparent Optical Resin
WANG Fu-xiang1, 2, PEI Song-hao1, 2, PENG Wei-xian1, 2*, WANG Dong-mei3, YANG Bai3, WANG Feng-min1, 2, LI Xin-guo1, 2
The optical properties of a transparent optical resin (HMA/ST) containing ternary rare earth complex are reported. Based on Judd-Ofelt(J-O) theory, the J-O parameters were calculated to be Ω2=10.139 4×10-20cm2, Ω4=3.810 9×10-20cm2, Ω6=9.050 7×10-20cm2 by using the emission spectrum of optical resin containing Eu(TTA)3phen-0.31 wt%. The J-O parameters were used to calculate the total radiative transition rate (456.6 s-1) and radiative lifetime (2 190.1 μs) of the excited state 5D0. The stimulated emission cross-sections σ and the fluorescence branch ratio β parameters for the transitions of 5D07FJ(where J′= 1, 2, 4 and 6) were also evaluated. By analyzing the calculated J-O parameters, it is concluded that the excited state of Eu3+ in optical resin has a long radiative lifetime and large emission cross-section, which shows that the optical resin containing rare earth complex can be used for stimulated emission amplification or as a laser material.
2006 Vol. 26 (02): 248-250 [Abstract] ( 1668 ) PDF (382 KB)  ( 766 )
251 Study on Thermal Decomposition of HMX Energetic Materials by In-situ FTIR Spectroscopy
LIU Xue-yong, WANG Xiao-chuan, HUANG Yi-gang, ZHENG Min-xia, WANG Lin, JIANG Yan, LUO Yi-wei
In-situ FTIR spectroscopy is a rising and dynamic technique. This technique, which combines the advantages of investigation in-situ and accurate structure analysis by FTIR spectsoscopy, can detect the chemical change of materials in different temperature with real time and obtain the relationship between micromechanism of materials and temperature. In the present paper, thermal decomposition of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) heated with 5 ℃·min-1 was investigated by in-situ FTIR spectroscopy. The results demonstrate that C—N bond cleavage and N—N bond cleavage of HMX occur at 205 ℃. With increasing temperature, the rupture rate of C—N bond is faster than that of N—N bond, which verifies that the cleavage of C—N bond is the dominant rupture form. The augment in tension of HMX cyclic confirms that intramolecular cyclization occurs in breakage of HMX. Eight kinds of gaseous products such as CO2,N2O,CO,NO,HCHO,HONO,NO2 and HCN were determined. According to the structure change in condensed state and gaseous products, the decomposition mechanism was deduced that HCHO, N2O, HONO and HCN were released due to the cleavage of C—N bond, and NO2 was released due to the cleavage of N—N bond.
2006 Vol. 26 (02): 251-254 [Abstract] ( 1763 ) PDF (428 KB)  ( 751 )
255 Study on the Spectral Properties of Gallium-Phthalocyanine-Chloride Doped Composite Gel Glass
QIN Jing, ZHAO Xu-cheng, LIN Ai-mei, ZHAN Hong-bing*
One of the focal topics in the field of phthalocyanine research is its materialization for practical use. The present paper reports the encapsulation of gallium phthalocyanine chloride (GaPcCl) into silica gel glass to make homogeneously doped composite by sol-gel technique. The spectral properties of the composite gel glass were carried out by IR, UV-Vis and fluorescence measurements. The results show that the introduction of GaPcCl doesn’t make noteworthy changes in the IR spectra of silica gel glass matrix. The absorption of GaPcCl dimers increases compared with DMF solution. The fluorescence intensity of GaPcCl is greatly enhanced in the composite gel glass.
2006 Vol. 26 (02): 255-258 [Abstract] ( 1814 ) PDF (463 KB)  ( 756 )
259 Study on Developing Calibration Models of Fat Acid Composition in Intact Rapeseed by Near Infrared Reflectance Spectroscopy
WU Jian-guo, SHI Chun-hai*, ZHANG Hai-zhen
Four hundred ninety seven rapeseed samples, which feature multi-year, multi-loci and highly variant characteristics, were collected as a raw set. The NIR spectra were pretreated by scatter correction and mathematics treatments, and calibration models of fat acid composition of intact rapeseed were developed by using the algorithm method of modified partial least square(MPLS). Meanwhile, three types of sample cups with different capacity were used to screen the suitable calibration model for rapeseed quality breeding. The results showed that the calibration model of 8-gram-sample was the best, and the calibration determination coefficient was in the range of 0.74-0.98. The calibration effects of 3-gram-sample, which were similar to those of 0.6-gram-sample, were good with high determination coefficient (RSQ1, 1-VR) and low error (SEC, SECV). Therefore, the calibration set with multi-year and multi-loci samples can improve the accuracy and repeatability of NIRS models. The fat acids NIRS models of intact rapeseed developed could be introduced into breeding lines’ selection, mutant screening and germplasm evaluation.
2006 Vol. 26 (02): 259-262 [Abstract] ( 1882 ) PDF (472 KB)  ( 720 )
263 Study on Dynamic Spectrum and Its Frequency Domain Extracting Method
LI Gang1,LI Xiao-xia1, 2,LIN Ling1,LIU Yu-liang1,WANG Yan1,3
For non-invasive blood components detection using near-infrared spectrum, eliminating the influence of the individual difference is very important. In the non-invasive component measurement, the individual discrepancy refers to the difference of personal feature in measured tissues except the pulsatile component of artery blood, including hairs, horny layer, subcutaneous tissue, muscle, skeleton etc. It is declared that the individual discrepancy is different from the personal feature; it is an important factor blocking the practice of the technology. In the present article, a new method of detecting blood components is presented, which is based on the principle of photoplethysmography and Fourier transform. With this method, the influence of individual difference caused by skin and other tissues can be mostly eliminated, and the absorbance of artery blood could be obtained. The concept of the frequency domain extracting method was presented. The experiment was done and the dynamic spectrum which only evaluates the pulsatile part of the entire optical signal was obtained. The advantage of dynamic spectrum with frequency domain extracting method is analyzed. The result shows that the method can be realized and has many advantages.
2006 Vol. 26 (02): 263-266 [Abstract] ( 1254 ) PDF (507 KB)  ( 796 )
267 Spectra Analysis of [MnHg(SCN)4(H2O)2]·2C4H9NO (MMTWD) Crystals
ZHU Ge1, LU Gui-wu1*, ZHANG Jun1,LAN Jian-hui1, LI Ying-feng1,WANG Xin-qiang2, XU Dong2, XIA Hai-rui2
The factor group symmetry analysis method was used to predict lattice vibrational modes of MMTWD single crystal, and it was found that there are no more than 297 and 148 theoretically observable Raman peaks and infrared reflection bands, respectively. The Raman and IR spectra were measured at room temperature. All the Raman and IR spectra peaks were assigned on the basis of the group theory and lattice dynamics theory. According to the Raman and IR spectra, the molecular structure of MMTWD crystal was discussed. From the results of the present theoretical and experimental works, the three-dimensional network structure of MMTWD crystal was identified. This structure provides the crystal with a large interaction force between molecules, which in turn induces high stability and macroscopic nonlinear optical properties.
2006 Vol. 26 (02): 267-270 [Abstract] ( 1814 ) PDF (441 KB)  ( 751 )
271 Prediction of IVDMD with Near Infrared Reflectance Spectroscopy (NIRS) in Maize Stalk
BAI Qi-lin1,4, CHEN Shao-jiang1*, DONG Xiao-ling2, MENG Qing-xiang2, YAN Yan-lu3, DAI Jing-rui1
The in vitro dry matter digestion (IVDMD) in maize stalk was analyzed with 161 samples selected from 600 samples of different eco-environments, hybrids and inbred lines, development stages, and various parts of the plants in two years. The technique of near infrared reflectance spectroscopy (NIRS) and partial least square regression (PLS) were used to establish the models by comparing several preprocessing procedures and wavelength ranges. The optimal models could be obtained in the range of 6 101.7-5 773.8 cm-1 and 4 601.3-4 246.5 cm-1 by the spectral data preprocessing of the Max-Min normalization. The model is suitable for measuring various sample IVDMD. The determination coefficients of the modes were 0.907 3 and 0.906 6 for cross and external validation, respectively. The root mean square error of prediction was 2.08%, and the coefficient of correlation(r) was 0.956 between NIRS predicted and actual IVDMD in these materials. The results showed that NIRS is a simple effective means for measuring IVDMD in maize stalk. The results are of great value of application in screening and evaluating quality constituents of silage maize.
2006 Vol. 26 (02): 271-274 [Abstract] ( 2214 ) PDF (476 KB)  ( 793 )
275 Study of Infrared Spectroscopic Analysis of Chinese Traditional Medicines Liuweidihuangwan
LIU Yang-qing1, ZHANG Xiao-wei1, WANG Shuang1, ZHAO Hui-hui, ZHAO Ping1
Seven types Luiweidihuangwan from six factories were chosen, randomly sampled, ground after being broken and dried, stirred with KB, and pressed into tablets. Infrared spectra of the tablets were obtained and compared. It is concluded that infrared spectra can be used to qualitatively analyse and distinguish patent medicines from different factories with different types and batches.
2006 Vol. 26 (02): 275-278 [Abstract] ( 701 ) PDF (478 KB)  ( 741 )
279 Investigation of Calculating the FRET Efficiency of Donor-Acceptor Pair
WANG Jin,WANG Jing*,SUN Yi-hong,MENG Ji-wu
The research on the method of calculating FRET efficiency is important to organic white LED research. In the present article, a new method of calculating the FRET efficiency of donor-acceptor pair by means of emission and excitation spectra was investigated. This method is easy to use to process data, needs only normal experiment equipments and doesn’t need the parameters such as fluorescence quantum yield. However it can only be used to calculate comparative result. With this method, the FRET efficiency of fluorescein sodium, α-naphthol, bromocresol purple and riboflavin with different concentrations was studied, and the results match the experimental results completely, so this method has proved to be reasonable.
2006 Vol. 26 (02): 279-281 [Abstract] ( 1257 ) PDF (359 KB)  ( 737 )
282 Synthesis and Spectral Study of Three Polyoxovanadium Clusters
SUN Rui-qing1, ZHANG Han-hui1, 2*, WU Xiao-yuan1, 2, HUANG Chang-cang1, CHEN Yi-ping1
Three polyoxovanadium clusters, [{Ni(phen)2}2V4O12]·H2O Ⅰ,[N(CH2CH2)3NH]Na(H2O)6{K4(H2O)4[V10O28]}(H2O)4 Ⅱ and [(CH3)4N]6[V15O36Cl] Ⅲ, have been synthesized under hydrothermal condition. The relationship between their properties and structures were studied by using FTIR, UV-Vis DRS and flurescence. The FTIR showed that the vibrational frequencies of the group are related to the structure of the materials. In UV-Vis DRS spectra of compound Ⅰ, there are four characteristic wide peaks at 200, 230, 260 and 350 nm corresponding to Ot→V, Oμ→Ni,Oμ→V charge transfer and phen’s π-π*, respectively. The fluorescence spectra of clusters have been studies. Finally, the quantum chemistry calculation was performed by Gaussian 98 program to explain the structure characteristic of compound Ⅰ.
2006 Vol. 26 (02): 282-286 [Abstract] ( 1961 ) PDF (548 KB)  ( 747 )
287 Spectral Study of Two Bi(Ⅲ) Contained Heteropolymate Compounds
WANG Yong-jing1,2, ZHANG Han-hui1, 2*, HUANG Chang-cang1, CHEN Yi-ping1, SUN Rui-qing1
Two Bi(Ⅲ) contained heteropolymate compounds Co5[Bi2Co2W20O70(H2O)6]·44H2O(Ⅰ)and Na3H2[Ce3(H2O)18Bi2W22O76]·23H2O(Ⅱ) have been synthesized under hydrothermal condition. The relationship between their properties and structures was studied by using FTIR, NIR FT-Raman, and UV-Vis DRS etc. The characteristic vibrational frequencies νas(MOd) and νs(M—Ob—M) is related to the structure of the materials.νas(M—Ob—M) is demonstrated to explain why the the oxidative ability becomes stronger when W atoms are substituted by Co atoms. In UV-Vis DRS spectra of compound Ⅰ and Ⅱ, there are two characteristic peaks at 254, 319 nm and 220, 310 nm coresponding Od→W and to Ob, c→W charge transfer,respectively. The wide and weak absorption band of compound Ⅰat 529 nm can be assigned as Co2+ d-d transfer. Finally, quantum chemistry calculation of compound Ⅰ was performed to explain the structure characteristic.
2006 Vol. 26 (02): 287-290 [Abstract] ( 1863 ) PDF (475 KB)  ( 713 )
291 Experiment Study of Alcohol-Water Mixtures Absorption and Fluorescence Spectra Induced by UV-Light
ZHU Tuo1, 2,CHEN Guo-qing1,YU Rui-peng1,LIU Ying2,NI Xiao-wu2*
By using equipment of UV-240 ultra-violet spectrophotometer and Sp-2558 multifunctional spectrometer system, the UV-light absorption spectra and the fluorescence spectra of propanol and isopropanol,as well as their comparison were studied. According to the results, propanol and isopropanol can be clearly distinguished with absorption spectra and fluorescence spectra. The reasons for difference spectra of the two liquids were also explained. Moreover, the fluorescence spectra of the four kinds of difference alcohol were compared and the results were discussed. The whole research outcomes will provide a new method for effective measurement of different alcohol, and also produce some valuable theoretical references to the calculation of quantum chemistry.
2006 Vol. 26 (02): 291-294 [Abstract] ( 759 ) PDF (445 KB)  ( 807 )
295 Applying Patial Least-Squares Discriminant Analysis on Autofluorescence Spectra to Identify Gastric Cancer
SHI Xiao-feng1, MA Jun1*, MAO Wei-zheng2, LI Ying1, ZHENG Rong-er1, MENG Ji-wu1
Measurement of fluorescence intensity was performed at excitation wavelength of 308 nm and emission wavelength in the range of 328-596 nm. The partial least-squares(PLS) method was used to analyze autofluorescence spectra of gastric cancer. The 42 normal samples and 42 cancer samples were taken from 42 gastric cancer patients. The normalized and centralized spectra of two kinds of samples showed similar but divergent patterns. PLS classification algorithm could differentiate cancer tissues from normal tissues with a sensitivity of 83.3%, a specificity of 95.2%, and a positive predictive value of 94.6%. We concluded therefore that the PLS method was a fast, effective choice for identification of gastric cancer.
2006 Vol. 26 (02): 295-298 [Abstract] ( 1681 ) PDF (537 KB)  ( 731 )
299 Study on Preparation of CuO/Cu2(OH)3Cl Powder and Its Spectrum Behavior for Photodegradation Decoloration of Dyes
DENG Fan-zheng, ZHU Ai-xia, YANG Rui
Ultrafine powder CuO/Cu2(OH)3Cl photocatalysts were prepared by CuCl2 and NaOH reaction and heating meuhod of microwave liquid phase. XRD and FTIR were used to investigate the properties of the CuO/Cu2(OH)3Cl powder, and photocatalytic degradation of dyes by the CuO/Cu2(OH)3Cl catalysts was investigated. The results show that the decoloration rate is related to the pH value of dyes solution, irradiation time, as well as the intensity of irradiation. After irradiation with sun light for 4 h, the decoloration rate was up to 90% when the concentration of dyes was 20 mg·L-1, the amount of catalyst was 40 mg and the acidity was pH 8 in 50 mL dye solution. Adding Fe3+, H2O2 and other catalyst can improve the decoloration rate greatly. So the decoloration of dyes was due to photocatalytic degradation by analyzing the IR spectrum and the ultraviolet spectrum, and the photocatalytic activity of CuO/Cu2(OH)3Cl powder is good in photocatalytic decoloration of dyes, such as amido black, indigo carmine and so on. The stability of photocatalytic nature of powder CuO/Cu2(OH)3Cl was studied, and CuO/Cu2(OH)3Cl powder can be recycled.
2006 Vol. 26 (02): 299-301 [Abstract] ( 1907 ) PDF (422 KB)  ( 754 )
302 Study on Crystalline and Properties of N’,N-Bis(n-butyl)-3,4,9,10-Perylene Tetracarboxylic Diimide
ZHANG Wen-guan, ZHAO Sheng-min
N’,N-Bis(n-butyl)-3,4,9,10-perylene tetracarboxylic diimide was synthesized , purified and crystallized, then IR, element analysis and X-ray diffraction were tested. The spectrum of UV-Vis absorption (maximum absorption peak at 524.80 nm), fluorescence emission (maximum emission intensity at 539.0 nm) and stokes displacement (15 nm) of the compound in DMF were analyzed. The UV-Vis absorption spectrum between 400 and 700 nm in a film can indicate that α-crystal has much stronger absorption peaks than β-crystal and that red shift of maximum absorption occurs (545 to 580 nm) when β-crystal is changed into α-crystal. It is obvious that CPS of α,β-crystal are respectively 2 508 at 26.0° and 1 891 at 25.2° in the X-ray diffraction pattern. The functional separate photoreceptors of α,β-crystal as charge generation material were made, and photoconductivity properties were tested after charging the sample and then using spectral light of 532 nm formed by a band path filter.
2006 Vol. 26 (02): 302-305 [Abstract] ( 1663 ) PDF (524 KB)  ( 694 )
306 Fluorescence Resonance Energy Transfer Quenching Method for Determination of Arsenic with Acridine Orange-Rhodamine B
LIU Bao-sheng, GAO Jing, LIU Zhi-chao, YU Li-na, YANG Da-cheng, YANG Geng-liang
A new method for the determination of trace arsenic was developed by using fluorescence resonance energy transfer from acridine orange(AO) to rhodamine B(RB). It was found that under the condition of λex/λem=470/580 nm, effective energy transfer could occur between AO and RB in the dodecyl benzene sodium sulfonate solution. The fluorescence intensity of RB was diminished by molybdoarsenide which was formed by the reaction of arsenic(Ⅴ) with molybdate in sulfuric acid medium. The detection limit of this method was 2.56 μg·L-1. This method was used for the determination of trace arsenic in tea. The range of determination for arsenic was 0.01-0.25 mg·L-1. The relative standard deviation for the determination of arsenic was 0.48%-0.64%. The recoveries for the addition of 0.01-0.03 mg·L-1 arsenic were 98%-103%. The method has been applied to the determination of arsenic with satisfactory results.
2006 Vol. 26 (02): 306-308 [Abstract] ( 1801 ) PDF (365 KB)  ( 810 )
309 Fluorescence Spectroscopy Study of Bovine Serum Albumin Quenched by Metal Ion
CHEN Xiao-bo,LI Song
The fluorescence spectrum of bovine serum albumin (BSA) influenced by copper ion, sodium ion and molybdenum ion is studied. The copper ion leads to obvious statistic quenching of BSA fluorescence. The dissociation constant of copper ion from BSA is about 2.38×10-4 mol·L-1. NaCl does not have quenching action on BSA fluorescence. It was illustrated that physiological saline, acting as the body fluid of organism, has very good protection action for life. The molybdenum ion has small statistic quenching effect on BSA fluorescence when its concentration is small. However, a new kind of avalanche quenching phenomenon occurs when the concentration of molybdenum ion is about 8.4×10-3 mol·L-1.
2006 Vol. 26 (02): 309-312 [Abstract] ( 1268 ) PDF (425 KB)  ( 747 )
313 Study on Properties and Resonance Rayleigh Scattering Spectra of Nanometer Selenium(0) Particles in Liquid Phase
BAI Yan1,LI Wei-jia1,WU Ya-qin1, 2,ZHENG Wen-jie1,YANG Fang1
In the HCl solution, selenium(Ⅳ) and excessive ascorbic acid(Vc) formed selenium(0), which homogeneously and steadily existed in liquid phase system. The Se(0) particles were aggregating spheres and their sizes were 26-243 nm from transmission electron microscope(TEM) and laser light scattering image. The nanometer Se(0) solution produced strongest resonance rayleigh scattering(RRS) at 470 nm. The intensity of RRS at 470 nm was linear with the concentration of Se(Ⅳ) in the range of 2.82×10-9-5.64×10-6 g·mL-1 (=0.997). Moreover, obvious Second-order scattering(SOS) and multiple frequence scattering(MFS) appeared at the same time.
2006 Vol. 26 (02): 313-316 [Abstract] ( 1288 ) PDF (513 KB)  ( 766 )
317 Resonance Light Scattering of Quercetin
ZENG Ming, LI Shu-wei*, DENG Jia-li, LI Xiao-yan, ZHAO Ke-qing
Resonance light scattering(RLS) and absorption spectra of Quercetin were studied in the present paper. In the solution with pH 3.30 to pH 6.50, the RLS singal was very strong and stable, but decreased sharply with a increase in pH when pH>6.50. In the B-R buffer solution at pH 4.00 , the RLS intensity at 497 nm was maximum and proportional to the concentration of quercetin. The linear range is 0.0-3.0×10-4 mol·L-1 with the detection limit of 3.1×10-7 mol·L-1. Quantum chemistry calculation showed that this enhancement of RLS occurred because the neutral molecules of quercetin assembled into supermolecular aggregates by 4-4’hydrogen-bond.This result completely accords with the spectral data from experiments.
2006 Vol. 26 (02): 317-320 [Abstract] ( 1224 ) PDF (498 KB)  ( 704 )
321 Study on the Mustard of Polysaccharides
HE Feng-ga,Hasenqimeng
The objective of this study is to isolate and purify the polysaccharides fractions from mustard and to determine the constituent characters. Hot water extracting and ethanol precipitating method were employed to isolate polysaccharides. After the removal of protein by Sevag method, the purified mustard polysaccharides were dried by frozen drier. The amount of total carbohydrates of mustard polysaccharides was measured with phenol-sulfuric acid method. IR spectrometry,UV-spectrophotometer, and automatic spectropolarimeter were used to determine the characteristic absorption and optical rotation of the polysaccharides,respectively. Size exclusion chromatography with laser light scattering technology was employed to measure the molecular masses. The monosaccharides contained in the mustard polysaccharides were analysed by HPLC. The amount of total carbohydrates in mustard polysaccharides is 98.96%. The molecular weight distribution was 1.42×104-2.55×106, and eighty percent was distributed in 2.1×105. The monosaccharide constituent of mustard polysaccharides were glucose,fructose,arabinose,galactose and xylose,and their molar proportions are 21.4∶12.89∶5.6∶4.1∶2.5, respectively.
2006 Vol. 26 (02): 321-323 [Abstract] ( 1367 ) PDF (419 KB)  ( 784 )
324 Studies on Quality Control Methods of Nuxvomica
HUANG Xi-ru, SUN Ze-dong, CAO Dong, WANG Shu-yue
Two quality control methods of nuxvomica were established for mutual. By selecting the appropriate measuring wavelength or wavelength range, the contents of strychnine and brucine in nuxvomica were determined without any preliminary separation by a new rapid spectrophotometry and a multi-wavelength linear regression spectrophotometry and with a computer program. The linear range of strychnine measured was 8.0-30.0 μg·mL-1 (r=0.999 9); The linear range of brucine measured was 7.0-31.2 μg·mL-1 (r=0.999 4). The average recoveries and relative standard deviations of strychnine and brucine were 98.18%-99.82%,0.56%-1.54% and 100.5%-100.6%,0.57%-0.62%, respectively. The methods are simple, rapid and reproducible, the interference of two components with each other may be eliminated and the methods are appropriate for quality control of nuxvomica.
2006 Vol. 26 (02): 324-326 [Abstract] ( 1214 ) PDF (363 KB)  ( 708 )
327 Study on Solid Phase Extraction and Spectrophotometric Determination of Cadmium with 2-[2-(5-Bromoquinolinylazo)]-5-Diethylaminophenol
WU Xian-hua1, HU Qiu-fen1, 2, YANG Guang-yu2, LIN Hong1, LI Hai-tao1
A new chromogenic reagent 2-[2-(5-bromoquinolinylazo)]-5-diethylaminophenol (5-Br-QADEAP) was synthesized, and its structure was verified by elemental analysis, infrared spectrum, and 1H nuclear magnetic resonance spectrum. The color reaction of 5-Br-QADEAP with cadmium was studied. In the presence of pH 8.0 buffer solution and Triton X-100 medium, 5-Br-QADEAP can react with cadmium(Ⅱ) to form a stable 2∶1 complex (5-Br-QADEAP: Cd(Ⅱ). The molar absorptivity is 1.60×105 L·mol-1·cm-1 at 595 nm. Beer’s law is obeyed in the range of 0-1.0 μg·mL-1. The cadmium ion in the samples can be enriched and separated by solid phase extraction with anion exchange resin cartridge. This method was applied to the determination of cadmium in water and food. The relative standard deviations are 2.5%-3.2%, and the recoveries are 96%-105%. The results are satisfactory.
2006 Vol. 26 (02): 327-330 [Abstract] ( 1842 ) PDF (522 KB)  ( 723 )
331 High Current Microsecond Pulsed Hollow Cathode Lamp Excited Ionic Fluorescence Spectrometry of Alkaline Earth Elements in Inductively Coupled Plasma with a Fassel-Torch
ZHANG Shao-yu, GONG Zhen-bin, HUANG Ben-li*
High current microsecond pulsed hollow cathode lamp (HCMP-HCL) excited ionic fluorescence spectrometry (IFS) of alkaline earth elements in inductively coupled plasma (ICP) with a Fassel-torch has been investigated. In wide condition ranges only IFS was observed, whilst atomic fluorescence spectrometry (AFS) was not detectable. More intense ionic fluorescence signal was observed at lower observation heights and at lower incident RF powers. Without introduction of any reduction organic gases into the ICP, the limit of detection (LOD, 3σ) of Ba was improved by 50-fold over that of a conventional pulsed (CP) HCL with the Baird sleeve-extended torch. For Ca and Sr, the LODs by HCMP-HCL-ICP-IFS and CP-HCL-ICP-AFS show no significant difference. Relative standard deviations were 0.6%-1.4%(0.1-0.2 μg·mL-1, n=10) for 5 ionic fluorescence lines. Preliminary studies showed that the intensity of ionic fluorescence could be depressed in the presence of K, Al and P.
2006 Vol. 26 (02): 331-335 [Abstract] ( 392 ) PDF (564 KB)  ( 702 )
336 Determination of Methylmercury in Biological and Sediment Samples by Capillary Gas Chromatography On-Line Coupled with Atomic Fluorescence Spectrometry
SHI Jian-bo,LIAO Chun-yang,WANG Ya-wei,JIANG Gui-bin*
A comprehensive method for the determination of methylmercury by capillary gas chromatography (GC) on-line coupled with atomic fluorescence spectrometry (AFS) was developed. The hyphenation system was carefully designed and the operation conditions such as injector temperature, carrier gas flow rate, make-up gas flow rate and argon flow rate were optimized in detail. The absolute detection limits (3σ) were 0.005 ng of Hg for both methylmercury (MMC) and ethylmercury (EMC). The relative standard deviations (RSD, n=5) for MMC and EMC at 10 ng·mL-1 of Hg levels were 2.5% and 1.3%, respectively. The method was evaluated by analyzing a certified reference material(DORM-2), and the MMC concentration determined was in good agreement with the certified value. In addition, the recoveries of MMC in two sediment samples were 70% and 77%, respectively. The proposed method was accurate, sensitive and suitable for the determination of MMC in biological and sediment samples.
2006 Vol. 26 (02): 336-339 [Abstract] ( 1734 ) PDF (484 KB)  ( 704 )
340 Study on Determination of Natrium, Vanadium and Aluminum Contents in Fuel Oil by ICP-AES
WEI Hai-jun1,GUAN De-lin1,SUN Pei-ting1,WANG Hong-zhi1,WANG Ze-en2,LUO Ze-ping2,LI Shao-hui2
The present paper considers synthetically all kinds of factors affecting excitation spectrum under traditional measurement conditions of fluorescence matter in liquor using plasma atomic emission spectra. The input power, carrier gas flow and assistant gas flow for BEC of Na, V, Al were optimized by testing. The input power, carrier gas flow and assistant gas flow for Na are 950 W, 0.6 L·min-1 and 1.0 L·min-1, respectively. The input power, carrier gas flow and assistant gas flow for V are 1 150 W, 0.5 and 1.1 L·min-1, respectively. The input power, carrier gas flow and assistant gas flow for Al are 1 150 W, 0.6 and 1.0 L·min-1, respectively. The result shows that the method is sensitive, accurate, linear in a wide range and highly precise. The precision is between 1.7%-2.2%, the linear ranges are between 0-100 mg·L-1 and recoveries are between 96%-105%.
2006 Vol. 26 (02): 340-343 [Abstract] ( 1774 ) PDF (369 KB)  ( 740 )
344 Determination of Metal Elements in Six Kinds of Desert Plants in Inner Mongolia by ICP-AES
LIU Ying, LI Jing-feng, GA Ri-di, MA Ning
In the present paper, the contents of metal elements from six kinds of desert plants, namely Haloxylon ammodendron, Caragana microphylla, Ammopiptanthus mongolicus, Salix bordensis, Elaeagnus angustifolia, and Salix psammophila in Inner Mongolian were determined by ICP-AES technique. The recovery ratio obtained by standard addition method ranged between 94.98% and 120.25%, and the RSD was lower than 3.4%. The results of determination showed that the major elements Ca, K, Mg, Na and Al, and trace elements essential to plant vital activities such as Fe, Mn, Cu and Zn exhibit different orders in content in the six kinds of desert plants, and the contents of four elements, Fe, Mn, Cu and Zn are lower than the average content of terrestrial plants. The above results provided reliable data and theory bases for improving environment in west China and choosing weather-resistant and sand-fixation tree species.
2006 Vol. 26 (02): 344-347 [Abstract] ( 1241 ) PDF (518 KB)  ( 730 )
348 Study on the Characteristics and Compositions of Fine Particles Left in the Solution after Decomposition of Plant Samples
WANG Xiao-ping1, GAO Wei-jian2,XIANG Su-liu2
After decomposition of plant standard reference materials bush twigs and leaves (GBW07602, GBW07603), poplar leaves(GBW07604) and tea(GBW07605) with either dry ashing method or wet digestion method, all kinds of fine particles left in the solution were collected and examined carefully by a scanning electron microscope(SEM), and their chemical composition were investigated by a SEM-affiliated energy-dispersive X-ray spectrometer at the same time. Moreover, the concentrations of some metal elements distributed among four different tea SRM-originated particle fractions extracted following the BCR sequential extraction procedure were determined by AAS and ICP-AES. It was found that decomposition methods have a great influence on the structure of fine particles. When dry ashing method is used, grey-colored, fluffy and porous partices can be produced, whereas fewer white-colored, compact particles can be produced when another method is used. As for chemical composition, all kinds of fine particles are almost the same, with silicon and aluminium as their main constituents, and calcium, iron, potassium, titanium and so on as their minor ones. The elemental distribution percentages in four different particle fractions in two kinds of plant-originated particles differ from element to element, which can result in severe negative errors when plant samples are decomposed and determined for elemental concentrations.
2006 Vol. 26 (02): 348-352 [Abstract] ( 790 ) PDF (840 KB)  ( 728 )
353 Study of Enhancement Effects in X-Ray Fluorescence Analysis for Multi-Layer Samples
HAN Xiao-yuan,ZHUO Shang-jun*,WANG Pei-ling
The enhancement effects in X-ray fluorescence analysis for multi-layer samples were studied. A computer program was developed based on the theoretical equations for X-ray fluorescence intensity calculation and used to calculate the intensities of primary fluorescence and secondary fluorescence, the ratios of intensities of secondary fluorescence to primary fluorescence, and the portions of intensities of secondary fluorescence in total fluorescence for Fe line in Zn/Fe and Fe/Zn film samples. It was found that the intensities of a characteristic line of an element in primary fluorescence and secondary fluorescence, the ratios of intensities of secondary fluorescence to primary fluorescence, and the portions of intensities of secondary fluorescence in total fluorescence were dependent not only on the thickness of the films but also on the position of the films in case of constant excitation conditions when multi-layer samples were tested by X-ray fluorescence analysis. When the thickness of Zn layer is the same as that of Fe layer, the calculated ratio of intensity of secondary fluorescence to total fluorescence of Fe varies with the thickness, and reaches up to 9% for Fe/Zn sample while up to 35% for Zn/Fe sample.
2006 Vol. 26 (02): 353-357 [Abstract] ( 1184 ) PDF (480 KB)  ( 727 )
358 Progress in Application of Surface Enhanced Raman Scattering Spectrum Technique
LUO Zhi-xun,FANG Yan*
Surface-enhanced Raman scattering spectrum is a very effective tool for detecting the interface character and interaction of molecules and expounding molecular configuration and adsorption behavior on the surface. It is becoming one of the best techniques to study interface effect, widely used in studying orientation and behavior of adsorption molecules on the surface and the feature of interface, as well as analysis of interphase tropism, configuration and conformation of biologic molecules. SERS technique is becoming a strong hand in surface science and electrochemistry, and widely used in trace analysis and even single molecule detecting (SM-SERS), medical chemistry, environmental sciences, biologic and medical systems, nano-materials and sensors. There is even conjunction application of SERS with other techniques. The present paper emphasized to summarize the headway of application research of SERS in the late years,along with the introduction of some work in our lab, especially, as a new field, on Fullerenes thin film and carbon nano-tube materials.
2006 Vol. 26 (02): 358-364 [Abstract] ( 1785 ) PDF (1073 KB)  ( 712 )
365 Application and Research Progress of Element Analysis of Urinary Calculi Using Modern Instruments
OUYANG Jian-ming
The analysis of elements of urinary stones can provide significant reference for the treatment and prevention of recurrence of urolithiasis. In the present paper, the application and research progress of element analysis of urinary stones by means of modern instruments were summarized. These techniques include X-ray photoelectron spectroscopy(XPS), proton induced X-ray emission(PIXE), energy dispersive X-ray analysis (EDX), electron microprobe analysis(EMPA), atomic emission spectroscopy(AES), atomic absorption spectroscopy(AAS), inductively coupled plasma spectroscopy(ICP), X-ray fluorescence(XRF), and ion selective electrode, etc.
2006 Vol. 26 (02): 365-371 [Abstract] ( 1240 ) PDF (863 KB)  ( 707 )
372 A Method for Auto-Extraction of Spectral Lines Based on Convolution Type of Wavelet Packet Transformation
LIU Zhong-tian1, WU Fu-chao1, LUO A-li2, ZHAO Yong-heng2
The important astrophysical information is hidden in spectral lines of astronomical spectra. The presen paper presents a method for auto-extraction of spectral lines based on convolution type of wavelet packet. This method consists of four main steps: First, the observed spectra are transformed by convolution type of wavelet packet with 4th scale. Then, the noise with coefficients of the 4th scale is eliminated by the local correlation algorithm and threshold in the wavelet packet domain. After that, middle and high frequency coefficients are selected to reconstruct the feature of the spectral lines. Finally, with the reconstructed feature of the spectral lines, spectral lines in observed spectra are searched. The results of our experiments, which include the spectral lines of stars, normal galaxies and active galaxies, show that the method can robustly and accurately extract the spectral lines. The method was applied to extract the SDSS spectral lines and compute the redshifts with those lines. By comparing the redshifts with those given by SDSS, the extraction has proven successful and practical.
2006 Vol. 26 (02): 372-376 [Abstract] ( 1267 ) PDF (567 KB)  ( 716 )
377 Automated Recognition of Quasars Based on Adaptive Radial Basis Function Neural Networks
ZHAO Mei-fang1, LUO A-li2, WU Fu-chao1, HU Zhan-yi1
Recognizing and certifying quasars through the research on spectra is an important method in the field of astronomy. This paper presents a novel adaptive method for the automated recognition of quasars based on the radial basis function neural networks (RBFN). The proposed method is composed of the following three parts: (1) The feature space is reduced by the PCA (the principal component analysis) on the normalized input spectra; (2) An adaptive RBFN is constructed and trained in this reduced space. At first, the K-means clustering is used for the initialization, then based on the sum of squares errors and a gradient descent optimization technique, the number of neurons in the hidden layer is adaptively increased to improve the recognition performance; (3) The quasar spectra recognition is effectively carried out by the above trained RBFN. The author’s proposed adaptive RBFN is shown to be able to not only overcome the difficulty of selecting the number of neurons in hidden layer of the traditional RBFN algorithm, but also increase the stability and accuracy of recognition of quasars. Besides, the proposed method is particularly useful for automatic voluminous spectra processing produced from a large-scale sky survey project, such as our LAMOST, due to its efficiency.
2006 Vol. 26 (02): 377-381 [Abstract] ( 1368 ) PDF (605 KB)  ( 771 )