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含能材料 2001年第1期9卷 8-9页

作者： HU Rong zu 1, YANG De suo 2. ZHANG Jiao qiang 3. (1. department of chemistry,Northwest University, Xi′an 710065,{2. 2. department of chemistry and Chemical engineering, baoji college of arts and science, baoji 721007,{2. 3. department of 西北大学陕西西安 710065 宝鸡文理学院陕西 721007 西北工业大学陕西西安 710072

Two relationships are established using the least squares method,between the kinetic parameters (the apparent activation energy and pre exponential constant),and the exothermic decomposition temperature and ther... 详细信息

关键词： critical temperature of thermal explosion decomposition temperature DSC energetic materials.

Gas-sensing properties of nanocomplex metal oxide

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Progress in Natural science:Materials International 2005年第7期15卷 669-672页

作者： CHEN Liangyuan, HE Zhusheng, YAN Tao, BAI Shouli, CHEN Aifan and LIU Chung Chiun ( Electronics Design Center, Case Western Reserve University, Cleveland, OH 44106, USA department of chemistry and Chemical {2., {3. University of arts and science, baoji 721007, china college of science, Beijing University of Chemical Technology, Beijing 10002., china) Electronics Design Center Case Western Reserve University Cleveland OH 44106 United States department of chemistry and Chemical {2. Baoji University of Arts and Science Baoji 721007 China college of science Beijing University of Chemical Technology Beijing 100029 China

The development of CuO/CeO2.nanocomposites as the sensing material of semiconductor gas sensors is reported. CuO/CeO2.nanocomplex oxide is prepared by modified sol-gel method that uses copper nitrate, cerium nitrate and ethylene glycol as precursors. The optimized synthesis parameters and processing condition have been established. The particle size and distribution, phase morphology, specific surface, electronic states of atoms and gas sensing properties have been systematically characterized by Transmission Electron Microscope (TEM), Brunauer Emmett Teller (BET), X-ray diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS) and gas sensitivity measurement. The results show that the sensor sensitivity depends on particle size, Cu/Ce cation ratio and calcination temperature. The effects of calcinations temperature and CuO loading on the gas sensitivity are also examined. The optimum calcination temperature and the CuO content for the highest sensitivity are 600 ℃and 12. , respectively. The combination of excellent thermal stability and tunable sensing properties through careful control of the processing parameters and selection of material composition gives rise to novel nanocomposites attractive to the sensitive and selective detection of a variety of toxic and combustible gases.

关键词： copper oxide cerium oxide nanocomposite CO gas sensitivity.

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微结构聚合物光纤中高双折射可调效应研究

物理学报 2008年第9期57卷 5729-5734页

作者：张亚妮宝鸡文理学院物理系宝鸡721007

通过在纤芯附近引入两个直径较大的空气孔诱导纤芯局部双折射,在包层减小x方向的孔间隔诱导包层双折射,设计实现了一种高双折射随波长可调效应的微结构光纤.采用全矢量平面波方法,以聚合物甲基丙烯酸甲酯为基材,对其偏振特性和基模模场... 详细信息

通过在纤芯附近引入两个直径较大的空气孔诱导纤芯局部双折射,在包层减小x方向的孔间隔诱导包层双折射,设计实现了一种高双折射随波长可调效应的微结构光纤.采用全矢量平面波方法,以聚合物甲基丙烯酸甲酯为基材,对其偏振特性和基模模场进行了研究.结果发现,该光纤基模双折射在光通信波段呈现两个最大值,且最大双折射大小和位置随光纤结构和波长的变化可以进行调节.通过调节光纤结构参数,模拟得到了该光纤具有高双折射和零偏振模色散的最佳设计参数.

关键词：导波与光纤光学双折射可调聚合物全矢量平面波法

Syntheses,characterization,crystal structure and magnetic properties of copper(Ⅱ) α,β-unsaturated carboxylate complexes with trimethyl phosphate

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Chinese science Bulletin 2001年第12期46卷 987-991页

作者： WANG Yaoyu, LIU Ping, SHI Qian, GAO Yici & SHI Qizhen1. department of chemistry, Northwest University, Xi’an 710069,{2. 2. department of chemistry, Wenzhou Teachers college, Wenzhou 3.2}003.{2. 3. department of chemistry, Lanzhou University, Lanzhou 73.000,{2. department of chemistry Northwest University Xi’an China department of chemistry Wenzhou Teachers College Wenzhou China department of chemistry Lanzhou University Lanzhou China

Two ternary complexes Cu2.4[OP(OCH3.3.2.(A represents CH2.CH-COO- and CH2.C(CH3.-COO-) have been synthesized, and elemental analyses, IR, ESR, electronic reflectance spectra and magnetic studies were carried out. The single crystal X-ray diffraction shows that Cu2.CH2.C(CH3.-COO]4[OP(OCH3.3.2.is triclinic, with space group P1, a = 1.0512.(13., b = 1.7559(5), c = 1.94479(3. nm, α =91.2.3.14)°,(β = 102.559(6)°,γ= 106.3.9(13.°, Z = 4 and R = 0.0668. Two copper(Ⅱ) atoms are bridged by four (a-methacrylate groups, and each copper(Ⅱ) atom is coordinated with a trimethyl phosphate molecule in the axial position, forming a distorted square pyramidal configuration. The symmetric center is between the two copper(Ⅱ) atoms, and the Cu-Cu bond distance is 0.2.098(6) nm. The Cu-Cu distance and magnetic studies suggest that there exist anti-ferromagnetic interactions between the two copper(Ⅱ) atoms.

关键词： copper(Ⅱ ) complex α β-unsaturated carboxylate trimethyl phosphate magnetic property crystal structure.

ON APPROXIMATION BY SPHERICAL ZONAL TRANSLATION NETWORKS BASED ON BOCHNER-RIESZ MEANS

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Journal of Systems science & Complexity 2005年第3期18卷 361-374页

作者： SHENGBaohuai LIHongtao departmentofMathematics ShaoxingCollegeofArtsandSciencesShaoxing312000China departmentofMathematics BaojiCollegeofArtsandSciencesBaoji721007China

A sequence of spherical zonal translation networks based on the Bochner-Riesz means of spherical harmonics and the Riesz means of Jacobi polynomials is introduced, and its degree of approximation is achieved. The results obtained in the present paper actually imply that the approximation of zonal translation networks is convergent if the action functions have certain smoothness.

关键词： spherical harmonics zonal translation networks approximation

Resolution of α-cyclohexyl-mandelic acid enantiomers by two-phase (O/W) recognition chiral extraction

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science china {2. 2007年第6期50卷 764-769页

作者： TANG KeWen1,2. ZHANG GuoLi2. HUANG KeLong2. LI Yuanjian3.& YI JianMin1,2.1 department of chemistry and Chemical {2., Hunan Institute of science and Technology, Yueyang 414000, china 2.college of chemistry and Chemical {2., Central South University, Changsha 410083. china 3.college of Pharmaceutical science, Central South University, Changsha 410078, china department of chemistry and Chemical {2. Hunan Institute of Science and Technology Yueyang China college of chemistry and Chemical {2. Central South University Changsha China college of Pharmaceutical science Central South University Changsha China

This paper presents a new chiral separation technology:two-phase(O/W)recognition chiral *** behavior of alpha-cyclohexyl-mandelic acid enantiomers was studied in the extraction system with D(L)-isobutyl tartrate in 1,2.dichloroethane organic phase and beta-CD derivatives in aqueous phase,and the influence of the kind and concentration of extractant and pH on extraction performance was *** experimental results indicate that two-phase(O/W)recognition chiral extraction is of strong chiral separation ***-^-CD,HE-beta-CD and Me-beta-CD have higher recognition ability for S-CHMA than that for R-CHMA,among which HP-beta-CD has the strongest ability;whereas,D-isobutyl tartrate has reversed recognition ability for *** the extraction system containing HP-beta-CD and D-isobutyl tartrate,e.e.% of S-CHMA in aqueous phase reached 2..6% by one stage extraction,and the distribution ratio for R-CHMA(k_R)and for S-CHMA(k_S)and separation factor(alpha)are 2.44,0.89 and 2.49,***,pH and concentration of extractant have great effects on chiral separation ***-phase(O/W)recognition chiral extraction has great significance for preparative separation of racemic compounds.

关键词： two-phase(W/0)recognition chiral extraction alpha-cyclohexyl-mandelic acid enantiomers

Quantum chemistry Study on Dissociation of Oxalyl Bromide

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Chinese Journal of Structural chemistry 2005年第11期 116-121+12页

作者： GENG Zhi-Yuana② WANG Dong-Meia, c WANG Yong-Chenga DAI Guo-Lianga LU Ling-Linga WANG Han-Qingb a (college of chemistry and Chemical {2., Northwest Normal University, Lanzhou 73.070,{3.) b (Lanzhou Institute of chemistry and Physics, The Chinese Academy of sciences, Lanzhou 73.000,{3.) c (department of chemistry, baoji college of arts & Sci.,{12.,{3.) college of chemistry and Chemical {2.， Northwest Normal University， Lanzhou 73.070，{3. college of chemistry and Chemical {2.， Northwest Normal University， Lanzhou 73.070，{3. department of chemistry， {2. {3. of arts & Sci.， baoji 721007，china Lanzhou Institute of chemistry and Physics，The Chinese Academy of sciences， Lanzhou 73.000，{2.

The multi-bond dissociation dynamics of oxalyl bromide ((BrCO)2. has been in- vestigated by DFT and CIS calculations. Upon the results, conclusion could be drawn that disso- ciation of C–Br bond of oxalyl bromide at the ground state (S0) is of barrierless. After the absorption of a photon, (BrCO)2.is excited to the first excited state and one of its C–Br bonds is broken to yield Br˙* and BrCOCO˙* free radicals. In addition, BrCOCO˙* with high energy is apt to release en- ergy, and ultimately, turns into BrCOCO˙of the ground state. The energy is adequate for BrCOCO˙to break down into Br˙and 2.O; at the same time the C–C and C–Br bonds of BrCOCO˙free radicals dissociate.

关键词： oxalyl bromide multi-bond dissociation BrCOCO˙free radical DFT

SYNTHESIS AND PROPERTIES OF NEW MESOGEN-JACKETED LIQUID CRYSTALLINE POLYMERS

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Chinese Journal of Polymer science 2000年第2期18卷 139-148页

作者： Qi-ding Mi Qi-feng Zhou department of Polymer science & {2., {3. of chemistry Peking University, Beijing 100871, china 北京大学北京

Some new mesogen-jacketed liquid crystalline polymers (MJLCP) with polymer backbones, spacers, and mesogenic units of different structures were synthesized by radical polymerization. The mesomorphic behavior of these polymers was examined using differential scanning calorimetry (DSC) and polarizing optical microscopy (POM). Their liquid crystallinity is influenced by the variation of polymer backbone, spacer, mesogenic unit and its terminal groups. The results show that 1) a more flexible polymer main-chain is more favorable to the formation of a liquid crystal phase, while 2. a flexible spacer will decrease the 'Jacket Effect' and the liquid crystallinity and 3. a subtle modification of the terminal groups on the mesogenic unit may also have a significant influence on properties of the polymers.

关键词： mesogen-jacketed liquid crystalline polymers polymer backbones spacers mesogenic units liquid crystallinity

A Series Piezoelectric Quartz Crystal Response Kinetics for *** Growth in the Presence of Cu(Ⅱ)

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Journal of Central South University 2000年第1期12卷 15-19页

作者： CHAI Li yuan 1,2.,WEI Wan zhi 2.YAO Shou zhuo 2.1. {3. of Metallurgical science and {2., Central South University of Technology, Changsha 410083. china 2. college of chemistry and Chemical {2., Hunan University, Changsha department of Metallurgical science and {2. Central South University of Technology Changsha China college of chemistry and Chemical {2. Hunan University Changsha China

The kinetics on the growth of *** in the presence of Cu(Ⅱ) was studied using of series piezoelectric quartz crystal (SPQC). Arsenic ion inhibits the growth of *** , which is consistent with the previous results by other measuring methods. This further demonstrates that the SPQC can monitor the chemical activity of *** growth. Cupric ion accelerates the growth of *** . The mechanism was discussed, i. e., copper promotes the protein enzyme of *** , rusticyanin, to form over the range of cupric ion concentration studied. The reaction order of cupric ion in accelerating the bacterial growth is 0.067. The growth of *** is dependent on temperature, the apparent reaction activation energy decreases from 2..56 kJ/mol to 18.3.0}kJ/mol because of the addition of 10 mg/L Cu(Ⅱ) to the bacterial growth solution of pH 2.0 at initial inoculum of 10%.

关键词： series piezoelectric quartz crystal T.ferrooxidans growth kinetics sigmoid curve cupric ion

Microwave-assisted reaction of peptide formation by amino acid with phosphate:Exploration of the most possible channels for the origin of life

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science china {2. 2006年第4期49卷 351-356页

作者： HU Rong1, TIAN Jinping2.& YIN Yingwu2.3.1. college of {3. & Environment Protection {2., Southwest University for Nationalities, Chengdu 610041, china 2. TH-UNIS Insight Co., Ltd., Beijing 100085, china 3. Key Laboratory of Bioorganic Phosphorus {3. & Chemical Biology, Ministry of Education, department of {3., Tsinghua University, Beijing 100084, china college of chemistry & Environment Protection {2. Southwest University for Nationalities Chengdu China TH-UNIS Insight Co. Ltd. Beijing China Key Laboratory of Bioorganic Phosphorus chemistry & Chemical Biology Ministry of Education Department of Chemistry Tsinghua University Beijing China

Microwave-assisted reaction of peptide formation by amino acids with phosphate was studied. The results showed that the products were a mixture of peptides containing dipeptide, oc- tapeptides and cyclic peptides, which could be obtained in a short time. Polyphosphate was also produced synchronously by the intermolecular condensation of phosphate. The polymerization de- gree reached 99% (pyrophosphate 64%, trimetaphosphate 3.%) after 2.h at 2.0℃ under microwave irradiation. The intermediates of the mixed anhydrides formed by the intermolecular condensation of phosphates and glycin were determined by ESI-MS. Peptides were also produced by the reaction of amino acids with trimetaphosphate in aqueous solution. The conversion degree of valine reached 46.5% even at room temperature. The cyclic process of peptide formation and phosphate polymeri- zation, regeneration and utilization in amino acids-phosphate system under microwave irradiation was detected and proved. Peptides could be continually formed only by inputting energy into this system. The above recycle may be the most possible process for primitive peptide formation in the origin of life.

关键词： microwave, phosphate, amino acid, peptide, origin of life.