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science China(Physics,Mechanics & Astronomy) 2006年第1期49卷 72-76页

作者： YANG Jianshe1,2. LI Wenjian1, JIN Xiaodong1, JING Xigang1, GUO Chuanling1, WEI Wei1 & GAO Qingxiang3.1. Institute of Modern Physics, Chinese Academy of sciences, lanzhou 73.000, China {2.,{3., China 3. life science school of lanzhou university, lanzhou 73.000, China Institute of Modern Physics Chinese Academy of Sciences Lanzhou China life science {2. of {3. west normal university Lanzhou China life science {2. of {3. university Lanzhou China

Human hepatoma and normal liver cells were irradiated with 12.6+ ion beams (LET = 96.05 keV/μm) and γ-rays at Heavy Ion Research Facility in lanzhou (HIRFL). The chromatid breaks and break types were detected using the premature chromosome con- densation technique. Our experimental results showed that chromatid breaks seem to have a good relation with 12.6+ absorbed dose and 12.6+ are more effective to induce chromatid breaks as compared to the γ-rays. For 12.6+ ion irradiation the major break was isochromatid break, while chromatid breaks were dominant for γ-ray irradiation. We also observed that the Relative Biology Effectiveness (RBE) of 12.6+ ion is about 2.5 times higher than that of γ-rays.

关键词： biological response, tumor cell, normal cell, heavy ion HIRFL.

A computer simulation of nucleation and growth of thin films

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science China(Physics,Mechanics & Astronomy) 2004年第4期47卷 442-451页

作者： ZHENG Xiaoping1,ZHANG Peifeng2.HE Deyan2.LIU Jun2. MA Jiantai3.1. Key Laboratory of Opto-Electronic Technology and Intelligent Control, Ministry of Education, {3. Jiaotong university,{2., China 2. {3. of Physical science and Technology, {3. university, {3. 73.000, China 3. {3. of Chemistry and Chemistry Engineering, {3. university, {3. 73.000, China Key Laboratory of Opto-Electronic Technology and Intelligent Control Ministry of Education Lanzhou Jiaotong University Lanzhou China school of Physical science and Technology Lanzhou University Lanzhou China school of Chemistry and Chemistry Engineering Lanzhou University Lanzhou China

A three-dimensional kinetic Monte Carlo technique has been developed for simulating the nucleation and growth of thin films. This model involves incident atom attachment, surface diffusion of the atoms on the growing surface and atom detachment from the growing surface. It takes some new effects into account, such as a significant improvement in calculation of activation energy for the atom diffusion, which renders the model more reasonable. In addition three optimum temperatures and the consistency of their dependence on deposition rate have been found out; the dependence of the surface roughness and relative density on the deposition rate has been discussed; and the approximation of freezing neighbour atoms and periodic boundary conditions has been applied.

关键词： Monte Carlo, thin film, nucleation, surface roughness, relative density.

Characteristics and origins of primary fluids and noble gases in mantle-derived minerals from the Yishu area,Shandong Province,China

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science China Earth sciences 2006年第1期49卷 77-87页

作者： MA Jinlong1,2. TAO Mingxin2.3.& YE Xianren2.1. Resources and Environmental {3., lanzhou {2., lanzhou 73.000, China 2. Key Laboratory of Gas Geochemistry, Institute of Geology and Geophysics, Chinese Academy of sciences, lanzhou 73.000, China 3. College of Resources science & Technology, Beijing normal {2., Beijing 100875, China Resources and Environmental school Lanzhou University Lanzhou China Key Laboratory of Gas Geochemistry Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou China College of Resources science & Technology Beijing Normal University Beijing China

Fluids and noble gases of mantle-derived materials are important tracers forthe mantle information. Compositions of primary fluids and noble gases in mantle-derived mineralsfrom the Yishu area, Shandong Province, China, were tested by the methods of heat-bursting andheat-melting respectively. The fluids are mainly composed of CO_2. CO and H_2. which account forabout 90% of the total, and are similar to the mantle-derived rocks from other areas of easternChina; ratios of ~3.e/~4He in almost all samples range from 0.82.Ra to 2.74 Ra, whereas^(40)Ar/^(3.)Ar from 2.9.5 to 758.8. Both ranges are much lower than those of the typical oceanmantle-derived samples (such as MORB) and primarily reflect the influences of the atmosphericcomponents and the radiogenic isotopes. Ratios of C/~3.e range from 2..6 x 10~9 to 1050 x 10~9,N_2.Ar from 92. to 56612. and N_2.~3.e from 2.5 x 10~9 to 2. x 10~9, similar to those in westernUnited States and New Zealand which belong to the tectonic plate collision regions. The ratios fallin the intersect of mantle-crust-atmosphere in the comprehensive tracer-charts, reflecting theinfluences of the atmosphere and the crusts with organic components. Our results suggest that thecomposition of the primary fluids and the isotopic ratios of the noble gases may either reflect theevolution process of mantle-derived rocks connected with the rise and eruption of magma, or theinfluence of the ancient subduction-plate on the continental mantle of this region.

关键词： noble gases, primary fluids, mantle-derived minerals, Yishu area.

Theory of truth degrees of propositions in the logic system Ln^＊

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science in China(Series F) 2006年第4期49卷 471-483页

作者： LI Jun1,2.& WANG Guojun1,3.1. Institute of Mathematics, Shaanxi normal university, Xi’an 710062. China 2. {2. of {3.s, lanzhou university of Technology, lanzhou 73.050, China 3. Research Center for {3., Xi’an Jiaotong university, Xi’an 710049, China Institute of Mathematics Shaanxi Normal University Xi’an China school of sciences Lanzhou University of Technology Lanzhou China Research Center for science Xi’an Jiaotong University Xi’an China

By means of infinite product of uniformly distributed probability spaces of cardinal n the concept of truth degrees of propositions in the n-valued generalized Lu- kasiewicz propositional logic system Ln^＊ is introduced in the present paper. It is proved that the set consisting of truth degrees of all formulas is dense in [0,1], and a general expres- sion of truth degrees of formulas as well as a deduction rule of truth degrees is then obtained. Moreover, similarity degrees among formulas are proposed and a pseudo-metric is defined therefrom on the set of formulas, and hence a possible framework suitable for developing approximate reasoning theory in n-valued generalized Lukasiewicz propositional logic is established.

关键词： truth degree similarity degree approximate reasoning.

Study on Green Residential Space Design

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IJLAI Transactions on Science and Engineering

IJLAI Transactions on science and Engineering 2024年第1期2卷 32-37页

作者： Yu Jiang Shenyang normal university No.2.3.Huanghe north Street Shenyang 110034China

With the ever-changing nature,green ecology has become an international trend of ***,the green ecological design of residential space has become the main melody of people’s *** always implement the concept of ecological and environmental protection in the design process,attach importance to the ecological effect of residential space,carry out reasonable budget and use of environmentally friendly decorative materials,reduce the waste of materials,save money and save resources at the same time,and protect the *** the same time,people began to put their hopes on the residential space design,which made the green residential space design began to *** the bold exploration and practice of designers,the design of green residential space will be endowed with more distinctive characteristics and unique *** from the concept of green design,this paper explores the method of green space design through typical analysis.

关键词： Green Residential space Haze

Influence of He-Ne laser irradiation on the excision repair of cyclobutyl pyrimidine dimers in the wheat DNA

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Chinese science Bulletin 2002年第10期47卷 818-821页

作者： HAN Rong, WANG Xunling & YUE Mingschool of life {2., {3.west university, Xi’an 710069, China school of life {2., Shanxi normal university, Linfen 041004, China school of life {2., lanzhou university, lanzhou 73.000, China school of life {2. Northwest University Xi’an China school of life {2. Shanxi Normal University Linfen China school of life {2. Lanzhou University Lanzhou China

Using agarose gel electrophoresis and T4-endo-deoxyribonuclease-V, which is a kind of restriction endonu-clease of cyclobutyl pyrimidine dimer (CPD), the impacts of He-Ne laser (5mW·mm-2. irradiation on DNA excision repair capacity in damaged wheat cells induced by enhanced ultraviolet-B (10.08kJ·m-2.d-1) radiation were studied. The results indicated that the content of endonuclease sensitive sites (ESS) was reduced by He-Ne laser irradiation, which formed in cells irradiated by enhanced ultraviolet-B. With the irradiation of He-Ne laser, the excision of CPDs and the reduction of single strand breaks (SSB) contents which were the endonuclease sensitive sites (ESS) digested by T4-endodeoxyribonuclease-Y had been stimulated in the wheat cells.

关键词： wheat ultraviolet-B He-Ne laser DNA excision repair.

On the Symmetry Classes of Functions

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Wuhan university Journal of Natural sciences 2005年第5期10卷 813-816页

作者： ZHU Ping~1,2. FAN Yun~3.1. school of Mathematics and Statistics, Wuhan university, Wuhan 43.072. Hubei, China 2. school of {3., Beijing university of Posts and Telecommunications, Beijing 100876, China 3. school of Mathematics and Statistics, Huazhong normal university, Wuhan 43.079, Hubei, China school of Mathematics and Statistics Wuhan University Wuhan Hubei China school of science Beijing University of Posts and Telecommunications Beijing China school of Mathematics and Statistics Huazhong Normal University Wuhan Hubei China

Let R be an integral domain of characteristic zero such that the corresponding group rings have block decompositions. We first prove that the submodule consisting of all the R-valued ξi-symmetric functions of several variables is a symmetry class, where ξi is any block character. Then we present a relationship among certain operators introduced for block character. Then we present a relationship among certain operators introduced for block characters. As a consequence, we obtain a decomposition of an arbitrary R-valued function of several variables. Finally, we describe the symmetry property of such summands and determine all the symmetry classes.

关键词： symmetry class strict symmetry class blockcharacter ξi-symmetric function block idempotent

cDNA cloning,sequence analysis,and recombinant expression of akitonin beta,a C-type lectin-like protein from Agkistrodon acutus

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Acta Pharmacologica Sinica 2004年第3期25卷 118-123页

作者： Xiang-dong ZHA1,2.Jing LIU1,Kang-sen XU3.1 school of life {2.,{3. of {2. and Technology,Hefei 2.002. school of life {2.,Anhui {3.,2.Hefei 2.003. National Institute for Control of Pharmaceuticals and Biological Products,Beijing 100050,China 3 school of life {2. University of Science and Technology Hefei 230026 National Institute for Control of Pharmaceuticals and Biological Products 北京 100050

AIM: To clone the cDNA of a new member of snake venom C-type lectin-like proteins, to study its structure- function relationships and to achieve its recombinant production. METHODS: PCR primers were designed based on the homology and cDNA was amplified by RT-PCR using total RNA from snake venom gland as the template. The PCR products were cloned into the plasmid pGEM-T and sequenced. The deduced protein sequence was analyzed with some bioinformatic programs. A recombinant expression plasmid was constructed using pBAD- TOPO as vector and transformed into *** TOP10 competent cells. RESULTS: A novel cDNA sequence encod- ing akitonin β was found and accepted by GenBank (accession number AF3.7100). Akitonin β consists of a typical carbohydrate recognition domain (CRD) of C-type lectins, and it is homologous with other snake venom C-type lectin-like proteins. It was predicted to be a platelet antagonist. Upon induction with arabinose rAkitonin β express- ing in E coli was achieved at a high level (superior to 150 mg/L). The recombinant fusion protein exhibited inhibitory activities on rat platelet aggregation in vitro. CONCLUSION: A new member of snake venom C-type lectin-like proteins was discovered and characterized, and an efficient recombinant expression system was estab- lished for its production.

关键词： snake venoms cDNA akitonin C-type lectin-like proteins recombinant proteins structure- activity relationship

Development and Application of High Performance X80 Line Pipe for the 2.(nd) west-East Gas Pipeline

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Journal of Iron and Steel Research International 2011年第S1期18卷 39-48页

作者： LI He-lin 1 , HUO Chun-yong 1 , JI Ling-kang 1, 2., LI Yang 1, 3.(1. CNPC Tubular Goods Research Institute, Xi’an 710065, China 2. . school of Material {3. and Engineering, Xi’an Jiaotong {2., Xi’an 710049, China 3. school of Material {3. and Engineering, {2. of {3. and Technology Beijing, Beijing 100083. China) CNPC Tubular Goods Res Inst Xian 710065 Peoples R China Xi An Jiao Tong Univ Sch Mat Sci & Engn Xian 710049 Peoples R China Univ Sci & Technol Beijing Sch Mat Sci & Engn Beijing 100083 Peoples R China

It is the development tendency of gas pipeline to improve strength of line pipe and transmission pressure, which is an important symbol of the progress of gas pipeline technology. The 2.d west-East Gas Pipeline (the 2.nd WEGP) is the largest-scale X80 high pressure gas pipeline project in the world. Through the joint development project by Pipeline Company, research institute, and steel company, a series of achievements of technology have been obtained, which makes it possible to apply pressure of 12.MPa and X80 LSAW and HSAW pipe for the 2.nd WEGP. Specifications of X80 steel and pipe have been issued based on API 5L. High performance X80 steel and pipe have been developed and meets the Specification. General design conception of applying HSAW pipe and LSAW pipe on gas transmission trunk line with large diameter and high pressure has been established. Failure control of the 2.nd WEGP has been carried out to avoid failure and reduce the lost which based on analysis of pipeline failure mode. In this paper, research and development of high performance X80 welded pipe, establishment of technical route of joint application of HSAW and LSAW steel pipe and key technology of failure control are emphatically discussed.

关键词： 2.nd WEGP acicular ferrite failure control arrest toughness strain-based design

Impacts of permafrost changes on alpine ecosystem in Qinghai-Tibet Plateau

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science China Earth sciences 2006年第11期49卷 1156-1169页

作者： WANG Genxu1,3., LI Yuanshou2., WU Qingbai2.& WANG Yibo3.1. Institute of Mountain Hazards and Environment, Chinese Academy of sciences, Chengdu 610041, China 2. Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of sciences, {2. 73.000, China 3. Resource and Environment {3., {2. university, {2. 73.000, China Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu China Resource and Environment school Lanzhou University Lanzhou China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China

Alpine cold ecosystem with permafrost environment is quite sensitive to climatic changes and the changes in permafrost can significantly affect the alpine ecosystem. The vegetation coverage, grassland biomass and soil nutrient and texture are selected to indicate the regime of alpine cold ecosystems in the Qinghai-Tibet Plateau. The interactions between alpine ecosystem and permafrost were investigated with the depth of active layer, permafrost thickness and mean annual ground temperature (MAGTs). Based on the statistics model of GPTR for MAGTs and annual air temperatures, an analysis method was developed to analyze the impacts of permafrost changes on the alpine ecosystems. Under the climate change and human engineering activities, the permafrost change and its impacts on alpine ecosystems in the permafrost region between the Kunlun Mountains and the Tanggula Range of Qinghai-Tibet Plateau are studied in this paper. The results showed that the per- mafrost changes have a different influence on different alpine ecosystems. With the increase in the thickness of active layer, the vegetation cover and biomass of the alpine cold meadow exhibit a significant conic reduction, the soil organic matter content of the alpine cold meadow ecosystem shows an exponential decrease, and the surface soil materials become coarse and gravelly. The alpine cold steppe ecosystem, however, seems to have a relatively weak relation to the permafrost environment. Those relationships resulted in the fact that the distribution area of alpine cold meadow decreased by 7.98% and alpine cold swamp decreased by 2..11% under the permafrost environment degradation during recent 15 years. In the future 50 years the alpine cold meadow ecosystems in different geomorphologic units may have different responses to the changes of the permafrost under different climate warming conditions, among them the alpine cold meadow and swamp ecosystem located in the low mountain and plateau area will have a relatively

关键词： permafrost environment, alpine cold ecosystem, statistics relationship, climate change, impacts, Qinghai-Tibet Plateau.