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Chinese Chemical Letters 1999年第8期10卷 625-628页

作者： Hong Zhong WANG Dan YAO Ruo Xi LAN Jia Xi XU Sheng JIN (college of chemistry and molecular {3.,{4., Beijing 100871) Beijing Univ Coll Chem & Mol Engn Beijing 100871 Peoples R China

2,3.Dihydro-2-phenyl-4.(4.methoxyphenyl)-1, 5-benzothiazepine reacts with ethoxycarbonyl carbene to give an unexpected compound 2,3.disubstituted-4.-1,4.benzothiazine Ⅲ. It was found to be a new rearrangement reactio... 详细信息

关键词： Benzothiazepine ethoxycarbonyl carbene rearrangement reaction

Entropy product measure for multipartite pure states

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Science China(Physics,Mechanics & Astronomy) 2006年第5期49卷 606-615页

作者： CAO Wancang1,2, LIU Dan2, PAN Feng3.& LONG Guilu2,4.1. Department of Physics, Chifeng college, Chifeng 024.01, China 2. Key Laboratory for Quantum Information and Measurements, Department of Physics, Tsinghua university, Beijing 100084. China 3. Department of Physics, Liaoning Normal university, Dalian 116029, China 4. Key Laboratory for Atomic and {3. Nano-Sciences, Tsinghua university, Beijing 100084. China Correspondence should be addressed to Long Guilu Department of Physics Chifeng College Chifeng 024001 China Key Laboratory for Quantum Information Measurements Department of Physics Tsinghua University Beijing 100084 China Department of Physics Liaoning Normal University Dalian 116029 China Key Laboratory for Atomic molecular Nano-Sciences Tsinghua University Beijing 100084 China

An entanglement measure for multipartite pure states is formulated using the product of the von Neumann entropy of the reduced density matrices of the constituents. Based on this new measure, all possible ways of the maximal entanglement of the triqubit pure states are studied in detail and all types of the maximal entanglement have been compared with the result of ‘the average entropy’. The new measure can be used to calculate the degree of entanglement, and an improvement is given in the area near the zero entropy.

关键词： multipartite pure state von Neumann entropy entanglement measure

Alterations in DNA methylation and genome structure in two rice mutant lines induced by high pressure

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Science China(Life Sciences) 2006年第2期49卷 97-104页

作者： SHEN Sile1,3. WANG Zhenwei3. SHAN Xiaohui2, WANG Hua3. LI Ling3. LIN Xuyun2, LONG Likun2, WENG Kenan4. LIU Bao2 & ZOU Guangtian1 1. National Laboratory of Superhard Materials, Jilin {4., Changchun 13.012, China 2. Institute of Genetics and Cytology, Northeast Normal {4., Changchun 13.024. China 3. college of Life Science, Jilin {4., Changchun 13.012, China 4. Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 51064., China 1. National Laboratory of Superhard Materials Jilin University Changchun 130012 China 3. college of Life Science Jilin University Changchun 130012 China 2. Institute of Genetics and Cytology Northeast Normal University Changchun 130024 China 4. Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

By using high-pressure treatment, two mutant lines were obtained from agenetically stable japonica rice cultivar Bijing3.. Genomic DNA of the mutant lines, together withthe original line (Bijing3.), was either undigested or digested by Hpa ⅡIMspⅠ, and then subjectedto molecular analysis using two markers, ISSR and RAPD. Results indicated that changes in the PCRamplification profiles of both markers are apparent in the two mutant lines compared with theoriginal rice cultivar, suggesting that there had been both sequence changes and DNA methylationmodifications in the mutant lines. Southern blot analysis using diverse sequences, including twocellular genes (S2 and S3., a set of retrotransposons (Osr7, Osr3., Tos19 and more), and a MITEtransposon family (mPing and Pong), confirmed the results, and indicated that changes in DNAmethylation pattern, genomic structure, and possible activation of some transposons indeed occurredin the mutant lines. Moreover, these changes are stably maintained through selfed generations and indifferent organs. Thus, our results indicate that it is possible to obtain stable mutants in riceby high pressure treatments, and the molecular basis of the mutants may include both genetic andepigenetic changes. Therefore, high hydrostatic pressure seems a promising approach for plantmutagenesis.

关键词： DNA methylation, genomic changes, high pressure, mutagenesis, rice.

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 chemistry 2006年第4期49卷 351-356页

作者： HU Rong1, TIAN Jinping2 & YIN Yingwu2,3.1. college of chemistry & Environment Protection engineering, Southwest {3. for Nationalities, Chengdu 61004., China 2. TH-UNIS Insight Co., Ltd., Beijing 100085, China 3. Key Laboratory of Bioorganic Phosphorus chemistry & Chemical Biology, Ministry of Education, Department of chemistry, Tsinghua {3., Beijing 100084. China 1. college of chemistry & Environment Protection engineering Southwest University for Nationalities Chengdu 610041 China 2. TH-UNIS Insight Co. Ltd. Beijing 100085 China 3. Key Laboratory of Bioorganic Phosphorus chemistry & Chemical Biology Ministry of Education Department of Chemistry Tsinghua University Beijing 100084 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 200℃ 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 4..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.

Large second-order optical nonlinearities of s-triazine derivatives: View from micro molecules to macro crystals

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Science China chemistry 2005年第3期48卷 203-209页

作者： FANG Qi1, LEI Hong2, CUI Yuezhi3. HUANG Zhenli4. XUE Gang1 & YU Wentao1 1. State Key Laboratory of Crystal Materials, Shandong university, Jinan 250100, China 2. School of Information Science and engineering, Shandong university, Jinan 250100, China 3. Department of Chemical engineering, Light Industry college of Shandong, Jinan 250100, China 4. Key Laboratory of Biomedical Photonics, Ministry of Education, Huazhong university of Science and Technology, Wuhan 4.0}074. China 1. State Key Laboratory of Crystal Materials Shandong University 250100 Jinan China 2. School of Information Science and engineering Shandong University 250100 Jinan China 3. Department of Chemical engineering Light Industry College of Shandong 250100 Jinan China 4. Key Laboratory of Biomedical Photonics Ministry of Education Huazhong University of Science and Technology 430074 Wuhan China

Three s-triazine derivatives have been synthesized and their structures been de-termined. These are Compound I: 2,4.dimethyl-6-(p-N,N-dimethylaminostyryl)-s-triazine (abbre-viated to NMe-1), Compound II: 2,4.dimethyl-6-(p-N,N-diethylaminostyryl)-s-triazine (to NEt-1), and Compound III: 2-methyl-4.6-bis(p-N,N-dimethylaminostyryl)-s-triazine (NMe-2). NMe-1 and NEt-1 molecules belong to the D-π-A type with a one-dimensional charge-transfer character. NMe-1 crystallizes to centrosymmetric P1 space group, while NEt-1 to non-centrosymmetric polar Cc space group with all of the molecular charge-transfer axes taking the same orientation. Under the irradiation of 1064.nm fundamental laser, NEt-1 powder crystals radiate a 2-order harmonic light with an intensity 4..8 times that of urea. The Λ typed NMe-2 molecule, which has a two-dimensional charge-transfer character, crystallizes to polar P21 space group. Its powder crystals exhibit a 2-order harmonic intensity 4..2 times that of urea. The quantum chemical cal-culations and tensor analyses have been carried out to reveal the dependence of the macro 2-order nonlinear optical (NLO) efficiency on the micro 2-order NLO coefficients (β) and on the crystalline packing styles.

关键词： s-triazine derivatives, synthesis, structure, SHG intensities of crystals, βvalues of molecules.

Oxidative Methylation of Toluene with Methane over Basic Zeolite Catalysts Promoted with Alkali Metal Bromides and Alkali Metal Oxides

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Chinese Chemical Letters 2000年第9期11卷 827-830页

作者： Ling Ping ZHOU Wei LI Ke Yi TAO Xuan Wen LI He Xuan LI college of chemistry and molecular {3.,{4., Beijing 100871 Department of chemistry, Nankai university, Tianjin 3.0071 peking Univ Coll Chem & Mol Engn Beijing 100871 Peoples R China Nankai Univ Dept Chem Tianjin 300071 Peoples R China

The catalytic effects for the oxidative methylation of toluene with methane over the basic zeolite catalysts prepared by promoting KY, KX, KM, KZSM-5 or KP with alkali-metal bromides and alkali-metal oxides have been investigated comparatively. The alkali-metal bromides promoted substrates are more effective than the alkali-metal oxides promoted systems. Moreover, the NaBr promoted systems are more active than KBr promoted systems. The most effective catalytic system (8wt%NaBr)/KZSM-5 gave a toluene conversion as high as 76.3. and a total C-8 selectivity of 76.4. (styrene/ethylbenzene=9.76) resulting in a total C-8 yield of 58.3..

关键词： styrene methane oxidative methylation alkali-metal oxides alkali-metal bromides

SYNTHESIS AND PROPERTIES OF A NEW AZOBENZENE SIDE-CHAIN POLYMER CONTAINING A TEMPO RADICAL

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Chinese Journal of Polymer Science 2002年第4期20卷 285-290页

作者： Yong Zhang Ze-da Xu Xing-he Fan Xiao-fang Chen Xin-hua Wan Qi-feng Zhou Department of Polymer Science and engineering college of chemistry and {3. engineering peking university, Beijing 100871, China peking Univ Coll Chem & Mol Engn Dept Polymer Sci & Engn Beijing 100871 Peoples R China

To allow anisotropies of optical properties in a magnetic field, nitroxide radical is introduced into the ortho-position of the phenylene ring in the side chain. A new azobenzene side-chain polymer (TEMPO-PAZ) containing TEMPO radical was synthesized. The polymer has a good solubility in organic solvents. The ESR spectrum of the polymer indicated three absorption lines characteristic of TEMPO radical. The optical phase conjugated responses (I-4. of the polymer films were investigated by degenerate four-wave mixing (DFWM). The experimental results showed that optical phase conjugated response of the TEMPO-PAZ could be easily controlled by choosing the appropriate direction of magnetic field presumably due to the nitroxide radical in the TEMPO-PAZ molecular structure. For the polymer investigated here, the nitroxide radical was introduced to increase optical phase conjugated response intensity in a magnetic field, aiming originally at searching for a new photo-active organic magnetic multifunctional materials.

关键词： azobenzene nitroxide radical polymer photo-active organic magnetic materials optical phase conjugated responses

Quantitative detection of ING1 mRNA under different gene regulation based on molecular beacon

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Chinese Science Bulletin 2006年第17期51卷 2059-2064页

作者： LIU Bin1,2,3.4. WANG Kemin1,2,3.4. XIAO Zhiqiang5,6, WANG Wei1,3.4. TAN Weihong1,2,3.4. SUN Yi5,6, TANG Hongxing1,3.4.& YANG Xiaohai1,3.4.. State Key Laboratory of Chemo/Biosensing and Chemometrics, Hu- nan university, Changsha 4.0082, China 2. Life Science and Biotechnology Institute, Hunan university, Chang- sha 4.0082, China 3. chemistry and Chemical Engineer {3., Hunan university, Changsha 4.0082, China 4. Hunan engineering Research Center for Bio-Nanotechnology, Hunan university, Changsha 4.0082, China 5. Medical Experiment Research Center, Xiangya Hospital, Central South university, Changsha 4.0008, China 6. Key Laboratory of Cancer Proteomics of Chinese Ministry of Health, Changsha 4.0008, China State Key Laboratory of Chemo/Biosensing and Chemometrics Hunan University Changsha China Life Science and Biotechnology Institute Hunan University Changsha China chemistry and Chemical Engineer college Hunan University Changsha China Hunan engineering Research Center for Bio-Nanotechnology Hunan University Changsha China Medical Experiment Research Center Xiangya Hospital Central South University Changsha China Key Laboratory of Cancer Proteomics of Chinese Ministry of Health Changsha China

The effects of drug treatment, gene transfection, and p53.RNA interference (RNAi) on level of ING1 mRNA in tumor cells were quantitatively detected with the help of ING1 molecular beacon (MB)/cRNA standard curve based on MB detection technology. Results showed that the level of ING1 mRNA could be upregulated by 5-FU treatment or ING1 transfection in low expression cell line of MCF-7 and be inhibited by silencing p53.with RNAi technology in normal expression cell line of CNE2. The level of ING1 varied from 7.7×10?16 to 53.4. 10?16 mol/μg total RNA of tumor cells. The results not only provided evidence for the regulation effects of gene expression but also were applied to investigat- ing the interaction of multigenes on signal transduc- tion pathway.

关键词： ING1 RT-PCR 定量分析分子信号 mRNA

Adsorption of surfactants onto acrylic ester resins with different pore size distribution

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Science China chemistry 2006年第5期49卷 445-453页

作者： YANG Weiben1,2,3.LI Aimin1,3.CAI Jianguo1,3.MENG Guanhua1,3.& ZHANG Quanxing1,3.1. State Key Laboratory of Pollution Control and Resource Reuse,School of the Environment,Nanjing university,Nanjing 210093.China 2. Nanjing college of Chemical Technology,Nanjing 21004.,China 3. Jiangsu engineering & Technology Research Center for Organic Toxicant Control and Resource Reuse,Nanjing 21003.,China 1. State Key Laboratory of Pollution Control and Resource Reuse School of the Environment Nanjing University Nanjing 210093 China 2. Nanjing college of Chemical Technology Nanjing 210048 China 3. Jiangsu engineering & Technology Research Center for Organic Toxicant Control and Resource Reuse Nanjing 210038 China

In this study, a series of acrylic ester resins with different pore size distribution were prepared successfully by varying the type and the amount of pore-forming agents. In order to inves-tigate the adsorption behavior and mechanism of surfactants on acrylic ester resins, three kinds of surfactants were utilized as adsorbates that were sodium 6-dodecyl benzenesulfonate (6-NaDBS), sodium 1-dodecyl benzene sulfonate (1-NaDBS) and sodium 1-dodecyl sulfonate, respectively. It was observed that the surface area was available in a particular pore size and an appropriate pore size of resins appeared to be more important for the adsorption of surfactants. As compared to commercial acrylic ester resins XAD-7 and HP2MG, 50# and 3.# resins exhibited more excellent adsorption properties toward 1-NaDBS and 6-NaDBS. The experimental equilibrium data were fitted to the Langmuir, and double-Langmuir models. Two models provided very good fittings for all resins over the temperature range studied. The investigation indicated that electrostatic attraction and hydrogen bond between resins and surfactants were the main forces and had an obvious effect on adsorption proc-ess.

关键词： acrylic ester resin, surfactant, adsorption, pore size distribution, isotherm.

Syntheses, structures and magnetic properties of a family of one-dimensional M(Ⅱ)-lanthanide(Ⅲ) (M = Ni(Ⅱ) and Zn(Ⅱ)) coordination polymers

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Science China chemistry 2007年第3期50卷 308-317页

作者： ZHANG Wen, ZHAO Fei, LIU Tao & GAO Song Beijing National Laboratory for molecular Sciences, State Key Laboratory of Rare Earth Materials chemistry and Applications, college of chemistry and molecular engineering, peking university, Beijing 100871, China 1. Beijing National Laboratory for molecular Sciences State Key Laboratory of Rare Earth Materials Chemistry and Applications College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

A series of 1D nickel(II)/zinc(II)-lanthanide(III) coordination polymers, [M(μ-L)2Ln(NO3.3.n·solvents (HL = bis(2-pyridylcarbonyl)amine; M = Ni, Ln = Gd (1·NiGd), Tb (2·NiTb), Dy (3.NiDy), Ho (4.NiHo), Y (5·NiY); M = Zn, Ln = Gd (6·ZnGd), Tb (7·ZnTb), Dy (8·ZnDy), Ho (9·ZnHo); solvents = H2O or H2O-ethanol), was synthesized and characterized. All of the complexes are isostructural at 293.K and crystallize in the orthorhombic space group Fddd. Magnetic measurements were performed on 1―9, where weak ferromagnetic interaction is found in 1·NiGd, ferromagnetic interaction in 2·NiTb and 3.NiDy, and antiferromagnetic interaction in 4.NiHo. A remarkable dc magnetic field dependence of ac susceptibilities was found in this series of complexes.

关键词： nickel lanthanide 3.-4. coordination polymer magnetic property