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Evolution of Nielsen-Olesen's String from Chern-Simons Field Theory

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Communications in Theoretical Physics 2007年第7期48卷 147-150页

作者： DUAN Yi-Shi Institute of Theoretical Physics,lanzhou university,lanzhou {3.,ChinaSHI Xu-Guang college of science,Beijing Forestry university,Beijing 100083.China Institute of Theoretical Physics Lanzhou University Lanzhou 730000 China college of science Beijing Forestry University Beijing 100083 China

We study the topology of Nielsen-Olesen's local field theory of single dual *** on the Chern-Simons field theory in three dimensons,we find many strings that can form world sheets in four *** stringshave important relation to the zero point of the complex scalar *** world sheets of strings can be expressed bythe topological invariant number,Hopf index,and Brower ***-Goto's action is obtained from the Nielsen'saction definitely by using φ-mapping theory.

关键词： φ-mapping theory dual string Nambu-Goto’s action Hopf index Brower degree

Mathematic Expression of Kinetic Compensation Effect and Relationship between the Exothermic Decomposition Temperature and Critical Temperature of Thermal Explosion of Eighty-six Energetic Materials

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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, China 2. Department of Chemistry and Chemical Engineering, Baoji college of Arts and science, Baoji 721007, China 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.

The characteristics of arc beam shaping in hybrid plasma and laser deposition manufacturing

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science China(Technological sciences) 2006年第2期49卷 238-247页

作者： ZHANG Hai’ou1, QIAN Yingping1,3. WANG Guilan1 & ZHENG Qiguang2 1. School of Material science and Technology, Huazhong university of science and Technology, Wuhan 43.074, China 2. Institute of Laser Technology and Engineering, Huazhong university of science and Technology, Wuhan 43.074, China 3. Mechanical Engineering college, Hubei university of Technology, Wuhan 43.068, China School of Material science and Technology Huazhong University of Science and Technology Wuhan China Mechanical Engineering college Hubei University of Technology Wuhan China Institute of Laser Technology and Engineering Huazhong University of Science and Technology Wuhan China

As a new direct metal prototyping technology,the hybrid plasma and laser deposition manufacturing (PLDM) is proposed in this paper. In order to figure out the characteristics of plasma arc beam and mould in the PLDM process of high temperature alloy, the high speed CCD camera is used to obtain the picture around the plasma arc. Afterwards the sketch of picture is clearly obtained. And the effect of laser parameter, such as average power, pulse width, pulse repetition frequency and the angle between laser beam and plasma arc beam on the plasma arc appearance, is studied experimentally. The results show that the modality of plasma arc beam is markedly influenced by laser beam. And the improvements of shape precision and surface state of the layer deposited by PLDM are confirmed.

关键词： plasma hybrid laser, direct deposition, plasma arc beam, molding character, high-temperature alloy.

Preparation and particle size characterization of Cu nanoparticles prepared by anodic arc plasma

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Rare Metals 2006年第2期25卷 172-176页

作者： WEI Zhiqiang XIA Tiandong FENG Wangjun DAI Jianfeng WANG Qing LI Weixue YAN Pengxun School of sciences Lanzhou University of Technology Lanzhou 730050 China college of Materials science and Engineering Lanzhou University of Technology Lanzhou 730050 China Institute of Plasma and Metal Materials Lanzhou University Lanzhou 730000 China

Copper nanoparticles were successfully prepared in large scale by means of anodic arc discharging plasma method in inert atmosphere. The particle size, specific surface area, crystal structure, and morphology of the samples were characterized by X-ray diffraction （XRD）, BET equation, transmission electron microscopy （TEM）, and the corresponding selected area electron diffraction （SAED）. The experimental results indicate that the crystal structure of the samples is fcc structure the same as that of the bulk materials. The specific surface area is 11 m^2/g, the particle size distribution is 3. to 90 nm, and the average particle size is about 67 nm obtained from TEM and confirmed from XRD and BET results. The nanoparticles with uniform size, high purity, narrow size distribution and spherical shape can be prepared by this convenient and effective method.

关键词： metal materials Cu nanoparticles anodic arc plasma particle size structure

Neuroglobin mutation associated with hypoxia adaptation in Tibet chicken

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Progress in Natural science:Materials International 2007年第12期17卷 1419-1424页

作者： Zhang Lifan1, Liu Chong2, Lian Linsheng3. Zhao Chunjiang1, Bao Haigang1 and Wu Changxin1(1. college of Animal science and Technology, China Agricultural university, Beijing 100094, China 2. college of Biological science, China Agricultural university, Beijing 100094, China 3. college of Animal science and Technology, Yunnan Agricultural university, Kunming 650201, China) college of Animal science and Technology China Agricultural University Beijing 100094 China college of Biological science China Agricultural University Beijing 100094 China college of Animal science and Technology Yunnan Agricultural University Kunming 650201 China

Globin protein family plays an important role in storing and transporting oxygen. As a newly reported globin, the revealed function of neuroglobin includes binding and storing oxygen as well as facilitating the utilization of oxygen in neuronal cells. In the present study, mutations in exons of chicken Ngb gene were identified with the method of sequencing and created restriction site PCR in Tibet chicken and other four lowland chicken breeds. The mutations of Lys-2224(E4)-Asn and Ser-2279(E4)-Gly were identified in exon 4 of the gene. The Lys-2224(E4)-Asn mutation existed only in Tibet chicken and the mutation frequencies increased with increasing altitude. Analysis of the haplotype and diplotype of the two mutations in Tibet chicken populations of different altitudes showed that the frequencies of TG haplotype and TTGG diplotype also increased with increasing altitude, while the reverse tendency was found on GGAA diplotype. Under the hypoxic simulation incubation, the main haplotype was TG in living embryos and GA in dead embryos. The results showed that the Lys-2224(E4)-Asn mutation may be a specific mutation associated with hypoxia adaptation in Tibet chicken.

关键词： Tibet chicken neuroglobin hypoxia adaptation Ngb gene mutation.

Statistical theory for hydrogen bonding fluid system of A_aD_d type (I): The geometrical phase transition

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science China Chemistry 2006年第6期49卷 499-506页

作者： WANG Haijun1,2, HONG Xiaozhong3. GU Fang1 & BA Xinwu1 1. college of Chemistry and Environment science, Hebei university, Baoding 071002, China 2. International Center for Materials Physics, Chinese Academy of sciences, Shenyang 110016, China 3. college of Physics science and Technology, Hebei university, Baoding 071002, China college of Chemistry and Environment science Hebei University Baoding China International Center for Materials Physics Chinese Academy of Sciences Shenyang China college of Physics science and Technology Hebei University Baoding China

The influence of hydrogen bonds on the physical and chemical properties of hydrogen bonding fluid system of AaDd type is investigated from two viewpoints by the principle of statistical mechanics. In detail, we proposed two new ways that can be used to obtain the equilibrium size distribution of the hydrogen bonding clusters, and derived the analytical expression of a relationship between the hydrogen bonding free energy and hydrogen bonding degree. For the nonlinear hydrogen bonding systems, it is shown that the sol-gel phase transition can take place under proper conditions, which is further proven to be a kind of geometrical phase transition rather than a thermodynamic one. Moreover, several problems associated with the geometrical phase transition and liquid-solid phase transition in nonlinear hydrogen bonding systems are discussed.

关键词： hydrogen bonding fluid, equilibrium free energy, geometrical phase transition.

Dusty cloud radiative forcing derived from satellite data for middle latitude regions of East Asia

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Progress in Natural science:Materials International 2006年第10期16卷 1084-1089页

作者： HUANG Jianping , WANG Yujie, WANG Tianhe and YI Yuhong ( college of Atmospheric sciences, lanzhou university,{3., China Gansu Provincial Meteorological Bureau, lanzhou 73.020, China) college of Atmospheric sciences Lanzhou University Lanzhou 730000 China Gansu Provincial Meteorological Bureau Lanzhou 730020 China

The dusty cloud radiative forcing over the middle latitude regions of East Asia was estimated by using the 2-year (July 2002-June 2004) data of collocated clouds and the Earth's radiant energy system (CERES) scanner and moderate resolution imaging spectroradiometer (MODIS) from Aqua Edition IB SSF (single scanner footprint). The dusty cloud is defined as the cloud in dust storm environment or dust contaminated clouds. For clouds growing in the presence of dust, the instantaneous short-wave (SW) forcing at the top of the atmosphere (TOA) is about - 275. 7 W/m for cloud over dust (COD) region. The clouds developing in no-dust cloud (CLD) regions yield the most negative short-wave (SW) forcing ( - 3.1.0 W/m2), which is about 12.8% stronger than those in COD regions. For long-wave (LW) radiative forcing, the no-dust cloud (CLD) is around 102.8 W/m2 , which is 20% less than the LW forcing from COD regions. The instantaneous TOA net radiative forcing for the CLD region is about - 208.2 W/m2, which is 42.1 % larger than the values of COD regions. The existence of dust aerosols under clouds significantly reduces the cooling effect of clouds.

关键词： dust storm cloud radiative forcing global warming dust aerosol-cloud-climate interaction.

Preliminary study on interaction between plant frictional root and rock-soil mass

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science China(Technological sciences) 2010年第7期53卷 1938-1942页

作者： YAN ZhiXin1’2, SONG Yun3. JIANG Ping1’2 & WANG HouYu4 1 Key Laboratory of Mechanics on Disaster and Environment in Western China (lanzhou university), Ministry of Education, lanzhou 73.000, China 2 School of Civil Engineering and Mechanics,{3., lanzhou 73.000, China 3.college of Civil Engineering and Mechanics, Central South university of Forestry and Technology, Changsha 410004, China 4 Air Force Engineering Design & Research Bureau, Beijing 100077, China Key Laboratory of Mechanics on Disaster and Environment in Western China (lanzhou university) Ministry of Education Lanzhou China School of Civil Engineering and Mechanics Lanzhou University Lanzhou China college of Civil Engineering and Mechanics Central South University of Forestry and Technology Changsha China Air Force Engineering Design & Research Bureau Beijing China

The interaction between lateral root system of woody plant and soil mass is similar to the one between shrub, herbage and soil mass, and has the effect of frictional reinforcement on slope soil. It plays an important role in reinforcing soil strength in shallow slope. Therefore, slope soil mass can be considered as a composite of soil and plant roots and the soil strength and stability of shallow slope soil mass are improved. However, current researches still remain on the level of qualitatively analyzing the relation between root and soil mass. In this paper, some exploratory researches on quantitative analysis of the interaction mechanism between root and soil mass are conducted. With the study of interaction between herbage root system (lateral root system of woody plants) and soil mass, the mechanical model of interaction between frictional root and soil mass is established. The accuracy of the model is verified by field experiments of Pinus Yunnanensis. The mechanical model provides a crucial theoretical guidance to quantitatively analyzing the interaction between plant root and soil mass; it also has certain values in application.

关键词： plant slope protection vegetation for slope protection mechanical model frictional root

Deposition features of Ni on self-assembled microtubule template from biolipid by electroless method

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science China Chemistry 2004年第3期47卷 228-234页

作者： FU Yubin1,2, ZHANG Lide1, ZHENG Jiyong2, FU Shangang3.& ZHU Mingwei3.1. Institute of Solid State Physics, Chinese Academy of sciences, Hefei 23.03., China 2. Luoyang Ship Material Research Institute, Luoyang 47103., China 3. college of life science, Henan Normal university, Xinxiang 453.02, China Institute of Solid State Physics Chinese Academy of Sciences Hefei China Luoyang Ship Material Research Institute Luoyang China college of life science Henan Normal University Xinxiang China

Diacetylenic glycero-phosphatidylcholine is a chiral molecule with amphiphilic property, and it can self-assembly into a lipid microtubular structure. The lipid microtubule is a stable structure formed by tightly wound helical ribbons, and the ribbon-wrapping patterns have a significant effect on their chemical deposition on the microtubules. The deposition of colloidal Pd catalyst occurs mainly on the helical edge of the wound helical ribbons to form helical deposition lines of colloidal Pd particles in the interior and exterior of the lipid microtubules, resulting in an uneven chemical deposition of Ni on the microtubules. Catalyzed by as-deposited colloidal Pd, metallized Ni microtubules are characterized by a helical form, which may be in relation to inner stress due to the thickness difference or the different deposition processes. The observation of microtom shows that metallized tubules have a hollow structure. Some metallized tubules have a kind of coaxial double layer structure observed in the direct experiment evidence, indicating that metallization can occur in the inner and outer surface of the lipid tubules. Both lipid microtubules and metallized microtubules can be used as vehicles for encapsulating biological active molecules to control their release and to develop micro-components in biological and mechanical systems. Keywords molecular self-assembly - lipid microtubules - helical pattern - site-specific deposition - electroless metallization

关键词： molecular self-assembly, lipid microtubules, helical pattern, site-specific deposition, electroless metallization.