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Substructure Prediction from infrared spectra by Using Support Vector Machines

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Chinese Chemical Letters 2005年第10期16卷 1354-1356页

作者： Jun Hong LIU Min Chun LU Fu Sheng NIE Xiao Yu FENG Meng Long LI College of Chemistry Sichuan University Chengdu 610064

The potential of support vector machines （SVMs） for the substructure elucidation of infrared spectra have been investigated. The trained SVMs can identify the 16 substructures with high accuracy.

关键词： infrared spectra substructures support vector machines.

Application of Embedded Zerotree Wavelet to the Compression of infrared spectra

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Chinese Chemical Letters 2003年第11期14卷 1193-1195页

作者： MengLongLI HuaYiQI FuShengNIE ZhiNingWEN BinKANG CollegeofChemistry.SichuanUniversity.Chenedu610064 CODI 27E.CentralAvenueSuite11PaoliPA19301USA

In this paper the embedded zerotree wavelet (EZW) method and Huffman coding are proposed to compress infrared (IR) spectra. We found that this technique is much better than others in terms of efficiently coding wavelet coefficients because the zerotree quantization is an effective way of exploiting the self-similarities of wavelet coefficients at various resolutions.

关键词： Embedded zerotree wavelet compress infrared spectra wavelet transform.

Alcohols＇ Classification by infrared spectra Segment Based on Support Vector Machines

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Chinese Chemical Letters 2006年第7期17卷 929-932页

作者： Wei XIE Fu Sheng NIE Meng Long LI Guang Ming LI Min Chun LU College of Chemistry Sichuan University Chengdu 610064

This paper studies various classifiers to identify primary, secondary or tertiary alcohols by using segmental spectra and their combinations to support vector machines （SVMs）. The results showed that the O-H in-plane bending absorption contributed most to identification their substitute. This conclusion disagrees with related known research results.

关键词： infrared spectra alcohols support vector machine information extraction.

Solvent effects on infrared spectra of 2-Methyl-4,5-dimethoxy-3-oxo-2H-pyridizine: Part 2. Binary Solvent Systems

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2002年第3期3卷 60-63页

作者：刘清桑文强徐小民 Department of Chemistry Zhejiang University Hangzhou China

This research on the solvent effects of 2 methyl 4,5 dimethoxy 3 oxo 2H pyridizine (MDOP) in binary solvent systems on the infrared spectra for MDOP in n hexane/CHCl 3 mixture solvents showed that there were three forms of carbonyl stretching vibration band [ υ (C=O)] of MPOP as the mole fraction of CHCl 3 in the binary solvents changes. In pure n hexane solvent, the υ (C=O) of MDOP appeared at a relatively high wavenumber. With CHCl 3 added, the υ (C=O) shifted to lower wavenumbers. Two new bands were observed over a certain range of mixture solvent compositions. The origin of the bands was discussed in the terms of two kinds of hydrogen bond together with their individual dependence on mixture composition. Comparisons were drawn for the solvent sensitivities of υ (C=O) for propanone.

关键词： infrared spectra 2 methyl 4 5 dimethoxy 3 oxo 2H pyridizine Binary solvent effects Carbonyl stretching vibration

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Syntheses and infrared spectra of Rare Earth Complexes with Diethyl Phosphate

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Journal of Rare Earths 1991年第2期9卷 95-99页

作者：李来明马爱增曾广赋李涵 Changchun Institute of Applied Chemistry Academia SinicaChangchun 130022China Department of Soil Chemistry Jilin University of AgricultureChangchun 130118China

The title complexes Ln(DEP),(Ln=La,Sm,Eu,Ho and Yb)were synthesized by reaction of triethyl phosphate with trivalent rare earth *** mechanism of thermo-decomposition of the complexes has been *** to their IR spectra,the residues of the thermo-decomposition of the complexes were identified as Ln(PO_3)_*** IR spectra were measured and principal IR bands were *** experimental results of the IR spectra of the complexes show that the title complexes have the same coordination form and mo- lecular configuration as rare earth,***,complex with dimethyl phosphate(Sm(DMP)_3).Each of the rare earth ion links three rare earth ions nearby through double“O-P-O”bridges to form a special network of rings-linking-rings,each of which consists of twenty-four *** Ln-O bond is principally ionic.

关键词： Rare earth complex Diethyl phosphate Mechanism of thermo-decomposition infrared spectra

The Splittings of p_± States in infrared spectra of Thermal Donors in Silicon

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Rare Metals 1992年第1期11卷 20-26页

作者：朱悟新王富咸 General Research Institute for Non-ferrous Metals Beijing China 100088

p -type CZ silicon crystals annealed at 450℃ have been investigated by low temperature infrared spectroscopy with high resolusion. It has been shown that the 2p± and 3p± bands of neutral thermal donors TD~° are all split into two bands, which have not been reported before. In addition, the concentrations ofindi- vidual TD_i and total TD have been derived from the heights of 2po bands, and the boron concentrations de- rived from that of 320 cm^(-1) band. The room temperature resistivities of samples have been evaluated and the comparison with practically measured resistivities have been made.

关键词： Czochralski silicon crystals Thermal donors infrared spectra Impurities and defects in silicon

Study on Membrane Microstructures and Characteristics of infrared spectra and Nitrogen Release of Solid-Liquid Reaction Coated Urea

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Agricultural Sciences in China 2004年第10期3卷 754-763页

作者： MAOXiao-yun FENGXin WANGDe-han SUNKe-jun LIAOZong-wen CollegeofResourcesandEnvironmentalSciences SouthChinaAgriculturalUniverisityGuangzhou510642P.R.China

The membrane microstructures and the mechanism of two coated ureas formed through solid- liquid reaction were observed by scanning electron microscope and infrared spectra, the relation of the structural characteristics with the nitrogen release feature was also discussed by combining with nitrogen dissolution in water. The results showed that the membranes were made of solid particles tightly connected to each other and were piled up layer by layer through liquid glue. Porosity and aperture of membrane were determined by compactness of piled layers and the particles in a single layer and also related to the characteristics of coating materials. Research of the infrared spectra of membrane, made of a solid powder and a liquid glue, proved that O-H on the solid surface was bonded with the double bond of the liquid glue, thus forming membrane and keeping it stable. It was found that the two coated ureas showed obvious differences in nitrogen releasing due to their membrane structures, the porosity and aperture of membrane were the critical factors for nitrogen releasing.

关键词： Coated urea Membrane Scanning eletron microscope infrared spectra Characte- ristics of nitrogen release

Isotopic Shifts of the infrared spectra of Cholic Acid and Sodium Cholate

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Chemical Research in Chinese Universities 1994年第1期10卷 59-62页

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关键词： Cholic acid Sodium cholate Deuteration infrared spectra Isotopic shift

Identification of Complex Ions of Nb(V)in FLINAK-O^(2-)System by infrared spectra

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Rare Metals 1993年第3期12卷 209-213页

作者：王新东段淑贞 ChristensenE. BjerrumN.J. University of Science and Technology Beijing Beijing 100083China The Technical University of Denmark 2800-LyngbyDenmark

The FT-IR spectra for K_2NbF_7-FLINAK-O^(2-) solution were measured and compared with the spectra of crystalline K_2NbF_7 and K_2NbOF_*** results show that the niobium fluoro-complex and/or oxyfluoro-complex ions are presented in these ***_7^(2-) complex ion is the predominant species in Nb(V)-FLINAK solution(not considering oxide impurity).The influence of O^(2-) on the oxyfluoro-complex ions shows that NbOF_6^(3-) as a stable monooxyfluoro-complex anion presented in FLINAK-O^(2-) systems and the number of NbOF_6^(3-) species are increased with increasing of O^(2-) when molar ratio of O^(2-)/Nb(V) is less than 1.

关键词： infrared spectra Niobium Fluoride melt Complex ion