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Spectral anomalies and spectral switches of partially coherent and polychromatic light diffracted at an aperture

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Science China(Physics,Mechanics & Astronomy) 2004年第1期47卷 24-35页

作者： Lü Baida1, 3 & PAN Liuzhan1, 2.1. Institute of Laser Physics and chemistry, Sichuan university, Chengdu 610064, China 2. Department of Physics, Luoyang Normal {2., Luoyang 47102., China 3. State Key Laboratory of Laser Technology, Huazhong university of Science and Technology, wuhan 430074, China Correspondence should be addressed to L Baida (email: badalu@***) Received July 10, 2.03 Institute of Laser Physics and chemistry Sichuan University Chengdu China State Key Laboratory of Laser Technology Huazhong University of Science and Technology Wuhan China Department of Physics Luoyang Normal College Luoyang China

Based on the propagation theory of partially coherent light in the space-frequency domain, the anomalous spectral behavior and spectral switches in the far field of partially coherent and polychromatic light diffracted at an aperture are studied. It is shown that, as compared with spatially fully coherent and polychromatic light whose spectral anomalies are induced only by aperture diffraction, the spectral anomalies and spectral switches of partially coherent and polychromatic light depend on the aperture diffraction, spatial correlationβ and bandwidth of the original spectrum. Detailed numerical calculations are made to illustrate the behavior of spectral switches of partially coherent and polychromatic light, and the results for spatially fully coherent and polychromatic light are treated as a special case ofβ=1 and included in our theory.

关键词： spectral anomaly spectral switch partially coherent and polychromatic light far field aperture diffraction

碱基在十二胺-N,N-二亚甲基膦酸改性氧化锆固定相上色谱行为的研究

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色谱 2005年第1期23卷 69-72页

作者：姚礼峰冯钰錡达世禄武汉大学化学与分子科学学院

研究了碱基在十二胺 N,N 二亚甲基膦酸(DDPA)改性氧化锆固定相(DPZ)上的色谱保留行为,考察了流动相中甲醇含量、流动相pH值、缓冲溶液中离子类型和离子强度对碱基保留的影响,对DDPA在氧化锆表面的吸附方式进行了研究。研究结果表明,DDP... 详细信息

研究了碱基在十二胺 N,N 二亚甲基膦酸(DDPA)改性氧化锆固定相(DPZ)上的色谱保留行为,考察了流动相中甲醇含量、流动相pH值、缓冲溶液中离子类型和离子强度对碱基保留的影响,对DDPA在氧化锆表面的吸附方式进行了研究。研究结果表明,DDPA仅以一个膦酸基与氧化锆结合,因而DPZ固定相表面上除了有长链的疏水烷基外,还有酸性的膦酸基和碱性的氨基。碱基分子中也存在氨基和酰胺基等极性基团,因此碱基在DPZ固定相上除了有疏水作用外,还具有电荷排斥作用、离子交换作用等多种保留机理。由于多种保留机理的存在,使得碱基在DPZ固定相上具有较好的分离选择性,在酸性条件下对碱基混合样品的分离取得了满意的结果。

关键词：氧化锆十二胺-N N-二亚甲基膦酸碱基

POLYMERIZATION OF ETHYLENE METHYL PHOSPHATE IN THE PRESENCE OF SODIUM POLY(ETHYLENE GLYCOL)ATE

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Chinese Journal of Polymer Science 1999年第3期17卷 259-264页

作者： Jie Wen Ren-xi Zhuo Lu Wang Laboratory of Biomedical Materials of the State te Education Commission of China, Department of chemistry, wuhan university, {2. 430072. China 武汉大学化学系生物医用高分子材料开放实验室湖北武汉 430072 武汉大学化学系生物医用高分子材料开放实验室湖北武汉

Poly(ethylene methyl phosphate)-poly(ethylene glycol)-poly(ethylene methyl phosphate) triblock copolymers carrying hydroxyl group at both chain ends were synthesized with sodium poly(ethylene glycol)ate as initiator. The effects of the factors such as solvent, amount of the initiator and reaction time were investigated. The copolymers were characterized by IR, H-1-NMR, H-1{P-31}-NMR, C-13-NMR, P-31{H-1}-NMR, and DSC. High molecular weight of the copolymer and high yield of the polymerization were achieved within 3 min at 2. degrees C. The polymerization process was studied by P-31{H-1}-NMR and transesterification was found during longer polymerization time.

关键词： ethylene methyl phosphate sodium poly(ethylene glycol)ate telechelic polymer block copolymer

Inclusion Property and molecular Modeling of Calix[4]arene Derivatives

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wuhan university Journal of Natural {2. 1999年第4期4卷 463-468页

作者： YU Xiao dong, LIN Lin, HAN Hui ming, WU Cai ying  college of chemistry and Environmental Science,{2., wuhan 430072. China wuhan university College of Chemistry and Environmental Science Wuhan China (GRID:grid.49470.3e) (ISNI:***)

The inclusion properties of two calix[4]arene derivatives 5,11,17,2. tetra tert butyl 2., 2. bis (isopropyl carbamoyl methoxy) 2.,2. diundecenyloxy calix[4]arene (C[4]A) and 2.,2. dibutoxy 5,11,17,2. tetra tert butyl 2.,2. diundecenyloxy calix[4]arene (C[4]B) were studied by gas chromatographic method. It was found that C[4]A could form inclusion complexes with benzene, toluene, methanol and ethanol while C[4]B could only form inclusion complex with methanol, which might be due to the different conformations of C[4]A and C[4]B. molecular modeling showed that CH/π and OH/π interactions played important roles in the forming of inclusion complexes.

关键词： calixarene gas chromatography molecular modeling inclusion interaction

Status of study on biological and toxicological effects of nanoscale materials

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Science China chemistry 2005年第5期48卷 385-394页

作者： WANG Bing1, FENG Weiyue1, ZHAO Yuliang1, XING Gengmei1, CHAI Zhifang1, WANG Haifang2.& JIA Guang3 1. Laboratory for Bio-Environmental Health sciences of Nanoscale Materials (Nanosafety Lab), Institute of High Energy Physics, Chi-nese Academy of sciences, Beijing 100049, China 2. {2. of chemistry and molecular Engineering, Peking university, Beijing 100871, China 3. Department of Occupational and Environmental Health sciences, School of Public Health, Peking university, Beijing 100083, China Laboratory for Bio-Environmental Health sciences of Nanoscale Materials (Nanosafety Lab) Institute of High Energy Physics Chinese Academy of Sciences Beijing China college of chemistry and {2. Engineering Peking University Beijing China Department of Occupational and Environmental Health sciences School of Public Health Peking University Beijing China

Because the physical and chemical properties of nanosized materials mostly differ from the existing microsized materials, their potential impacts on human health and the envi-ronment will be topics under the serious discussions in press and in a number of international scientific journals. We analyze and summarize the existing data of the experimental study on the biological activities and adverse effects of nanoscale materials/particles including single wall carbon nanotubes, multi wall carbon nanotubes, titanium oxide and iron powders. Though some biological behaviors of nanoscale materials observed cannot be understood on the basis of the current knowledge, as the existing data are mostly preliminary, it is too early to make some ex-clusive conclusions on biological activities (or the toxicity) of any of nanoscale materials. The experimental techniques, the current topics, and the future research directions for this new re-search field are also discussed.

关键词： nanomaterials, single wall carbon nanotubes, multi wall carbon nanotubes, titanium oxide and iron, biological activity and toxicological effect.

Synthesis of Cyclic Core Dendritic Polymer and Its Usage as a Vector for Transferring Foreign DNA into Human Cells

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Chinese Chemical Letters 1998年第7期9卷 635-638页

作者： Bo DU Rong Jia ZHOU Ren Xi ZHUO (Laboratory of Biomedical Polymer Materials of the State Education Commission of China, Department of chemistry )(Department of Genetic, college of Life {2.,wuhan university, wuhan 430072. Lab. Biomed. Poly. Mat. State E.C.C. Department of Chemistry Wuhan University Wuhan 430072 China Department of Genetic College of Life Sciences Wuhan University Wuhan 430072 China

Cyclic core dendritic polymer is a new type of synthetic polymer. We describe the first synthesis of a serial dendrimers with a core of 1,4,7,10-tetraazacyclododecane. The ability of generation 4 of dendrimers to function as an effective gene delivery vectors was also investigated. Results from fluorescent in situ hybridization (FISH) show that the dendrimer has good affinity to both DNA and human small intestine cancer metastatic (HICMA) cells. the LacZ gene was highly expressed in the cells.

关键词： dendrimer 1,4,7,10-tetraazacyclododecane Michael addition transfection DNA

Inositol 1,4,5-trisphosphate 3-kinases:functions and regulations

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Cell Research 2005年第2期15卷 83-91页

作者： Hui Jun XIA*, Guang YANGKey Laboratory of MOE for Plant Developmental Biology, college of Life sciences,{2., wuhan, hubei 430072.China KeyLaboratoryofMOEforPlantDevelopmentalBiology CollegeofLifeSciencesWuhanUniversityWuhanHubei430072China

Inositol 1,4,5-trisphosphate 3-kinase (IP3 3-kinase/IP3K) plays an important role in signal transduction in animal cellsby phosphorylating inositol 1,4,5-trisphosphate (IP3) to inositol 1,3,4,5-tetrakisphosphate (IP4). Both IP3 and IP4 arecritical second messengers which regulate calcium (Ca2.) homeostasis. Mammalian IP3Ks are involved in many biologicalprocesses, including brain development, memory, learning and so on. It is widely reported that Ca2. is a canonicalsecond messenger in higher plants. Therefore, plant IP3K should also play a crucial role in plant development. Recently,we reported the identification of plant IP3K gene (AtIpk2./AtIP3K) from Arabidopsis thaliana and its ***, we summarize the molecular cloning, biochemical properties and biological functions of IP3Ks from animal, yeastand plant. This review also discusses potential functions of IP3Ks in signaling crosstalk, inositol phosphate metabolism,gene transcriptional control and so on.

关键词： inositol 1 4 5-trisphosphate 3-kinase (IP3 3-kinase/IP3K) inositol polyphosphate kinase (Ipk) inositol phos-phate multikinase (Ipmk) calcium (Ca2.) signal transduction

Electronic Structure and Thermoelectric Properties of Ca_3Co_4O_9

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Journal of wuhan university of Technology(Materials Science) 2006年第1期21卷 13-15页

作者：闵新民 Department of Applied chemistry Wuhan University of TechnologyWuhan 430070China

The relation among electronic structure, chemical bond and thermoelectric property of Ca3 Co4 O9 was studied using density function and discrete variation method （DFT-DVM）. The gap between the highest valence band （HVB） and the lowest conduction band （LCB） shows a semiconducting property. Ca3 Co4 O9 consists of CoO2.and Ca2.CoO3 two layers. The HVB and LCB near Fermi level are only mainly from O（ 2.） 2. and Co （2. 3d in Ca2.CoO3 layer. Therefore, the semiconducting or thermoelectric property of Ca3 Co4 O9 should be mainly from Ca2.CoO3 layer, but it seems to have no direct relation to the CoO2.layer, which is consistent with that binary oxides hardly have a thermoelectric property, but trinary oxide compounds have quite a good thermoelectric property. The covalent and ionic bonds of Ca2.CoO3 layer are both weaker than those of CoO2.layer. Ca plays the role of connections between CoO2.and Ca2.CoO3 layers in Ca3 Co4 O9, decrease the ionic and covalent bond strength, and improve the thermoelectric property.

关键词： cobaltite electronic structure chemical bond thermoelectric property

高等植物线粒体与细胞核和叶绿体之间遗传物质的水平转移

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生物化学与生物物理进展 2003年第4期30卷 546-548页

作者：易平刘义朱英国武汉大学化学与分子科学学院武汉430072 武汉大学植物发育生物学教育部重点实验室武汉430072

在线粒体基因组中存在着来自细胞核和叶绿体的DNA ,这些外源DNA的存在增加了线粒体基因组的复杂性 .

关键词：高等植物线粒体细胞核叶绿体遗传物质水平转移