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Radiobiological response of human hepatoma and normal liver cells exposed to carbon ions generated by Heavy Ion Research Facility in lanzhou

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Science china({1.,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 730000,{3. 2. Life Science School of North West Normal university, lanzhou 73.070,{3. 3. Life Science School of lanzhou university, lanzhou 730000,{3. Institute of modern {1. Chinese Academy of Sciences Lanzhou China Life Science School of North West Normal university Lanzhou China Life Science School of lanzhou university Lanzhou China

Human hepatoma and normal liver cells were irradiated with 1.C6+ 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 1.C6+ absorbed dose and 1.C6+ are more effective to induce chromatid breaks as compared to the γ-rays. For 1.C6+ 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 1.C6+ ion is about 2.5 times higher than that of γ-rays.

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

X-ray spectra induced by ^(1.9)Xe^(q+) impacting the metal surface

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Science china({1.,Mechanics & Astronomy) 2008年第1期51卷 82-89页

作者： ZHANG XiaoAn 1.2 ,XIAO GuoQing 1.,YANG ZhiHu 1.,CHEN XiMeng 3.,ZHAO YongTao 1., LI FuLi 4 ,WANG Li 1.2 ,CUI Ying 3.,ZHANG HongQiang 3.&ZHAN WenLong 1.1.nstitute of modern physics,Chinese Academy of Sciences,lanzhou {3.,china 2Department of physics,Xianyang Normal university,Xianyang 71.000,china 3.epartment of modern physics,lanzhou university,lanzhou {3.,china 4Department of Applied physics,Xi’an Jiaotong university,Xi’an 71.049,china Institute of modern {1. Chinese Academy of Sciences Lanzhou China Department of physics Xianyang Normal University Xianyang China Department of modern {1. Lanzhou University Lanzhou China Department of Applied physics Xi’an Jiaotong University China

Using the slow highly charged ions 1.9 Xe q+ (q=25,26,27;initial kinetic T0≤4.65 keV/a.u.)to impact Au surface,the Au atomic Mαcharacteristic X-ray spectrum is *** result shows that as long as the charge state of projectile is high enough,the heavy atomic characteristic X-ray can be effectively excited even though the incident beam is very weak(nA magnitude),and the X-ray yield per ion is in the order of 1.-8and increases with the kinetic energy and potential energy of *** measuring the Au Mα-X-ray spectra,Au atomic N-level lifetime is estimated at about 1.3.×1.-1.s based on Heisenberg uncertainty relation.

关键词： slow highly charged ions characteristic X-ray level lifetime

X-ray spectra induced in highly charged 40Ar^q+ interacting with Au surface

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Science china({1.,Mechanics & Astronomy) 2006年第2期49卷 203-212页

作者： ZHANG Xiao’an1,2, XIAO Guoqing1, YANG Zhihu1, CHEN Ximeng3. ZHAO Yongtao1, LI Fuli4, ZHANG Yinping1, CUI Ying3. ZHANG Hongqiang3. XU Xu3. SHAO Jianxiong3.& ZHAN Wenlong11. Institute of modern physics, Chinese Academy of Sciences, lanzhou 730000,{3. 2. Department of physics, Xianyang Normal university, Xianyang 712000,{3. 3. Department of modern physics, lanzhou university, lanzhou 730000,{3. 4. Department of Applied physics, Xi’an Jiaotong university, Xi’an 710049,{3. Institute of modern {1. Chinese Academy of Sciences Lanzhou China Department of physics Xianyang Normal University Xianyang China Department of modern {1. Lanzhou University Lanzhou China Department of Applied physics Xi’an Jiaotong University Xi’an China

By use of optical spectrum technology, the spectra of X-ray induced by highly charged 40Arq+ ions interacting with Au surface have been studied. The results show that the argon Kα X-ray were emitted from the hollow atoms formed below the surface. There is a process of multi-electron exciting in neutralization of the Ar1.+ion, with electronic con-figuration 1.2 in its ground state below the solid surface. The yield of the projectile Kα X-ray is related to its initial electronic configuration, and the yield of the target X-ray is related to the projectile kinetic energy.

关键词： highly charged ion hollow multi-electron excitation X- ray.

Kinetic energy and charge state effects in the X-ray emission of Mo surface induced by Xe^(q+)(q=25,29) ions

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Science china({1.,Mechanics & Astronomy) 2008年第9期51卷 1240-1244页

作者： CUI Ying1,YANG ShengSheng2,YANG ZhiHu3.XU JinZhang1,ZHANG HongQiang1,XU Xu1,SHAO JianXiong1,LIU ZhaoYuan1,XIAO GuoQing3.ZHANG XiaoAn4,ZHAO YongTao3.ZHANG YanPing3.& CHEN XiMeng1 1 Department of modern physics,lanzhou {3.,lanzhou 730000,china 2 National Key Laboratory of Vacuum & Cryogenics Technology and physics,lanzhou 730000,china 3.Institute of modern physics,Chinese Academy of Sciences,lanzhou 730000,china 4 Normal College of Xianyang,Xianyang 713.00,china Department of modern {1. Lanzhou University Lanzhou China National Key Laboratory of Vacuum & Cryogenics Technology and physics Lanzhou China Institute of modern {1. Chinese Academy of Sciences Lanzhou China Normal College of Xianyang Xianyang China

L-shell X-ray spectra of Mo surface induced by Xe25+ and Xe29+ were measured. The X-ray intensity was obtained in the kinetic energy range of the incident ions from 3.0 to 600 keV. The relationship of X-ray intensity ... 详细信息

关键词： X-ray surface kinetic energy and charge state effect Xeq+

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 School,{1., lanzhou 730000, china 2. Key Laboratory of Gas Geochemistry, Institute of Geology and Geo{3., Chinese Academy of Sciences, lanzhou 730000, china 3. College of Resources Science & Technology, Beijing Normal university, Beijing 1.0875, 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 eastern{1.; ratios of ~3.e/~4He in almost all samples range from 0.82 Ra to 2.74 Ra, whereas^(40)Ar/^(3.)Ar from 299.5 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 27.6 x 1.~9 to 1.50 x 1.~9,N_2/Ar from 927 to 5661., and N_2/~3.e from 2.5 x 1.~9 to 27 x 1.~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.

X-ray spectra induced by slow highly charged Ar^(q+) ions in collision with Nb surface

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Science china({1.,Mechanics & Astronomy) 2008年第10期51卷 1463-1469页

作者： YANG ZhiHu1. CUI Ying2, CHEN XiMeng2, SONG ZhangYong1. SHAO JianXiong2, RUAN FangFang1. ZHANG HongQiang2, DU Juan2, LIU YuWen2, GAO ZhiMing2, ZHANG XiaoAn3. ZHU KeXin1. YU DeYang1.& CAI XiaoHong1.1.Institute of {1. physics, Chinese Academy of Sciences, lanzhou 730000,{3. 2 Department of {1. physics, lanzhou university, lanzhou 730000,{3. 3.Department of physics, Xianyang Normal College, Xianyang 71.000,{3. Institute of modern {1. Chinese Academy of Sciences Lanzhou China Department of modern {1. Lanzhou University Lanzhou China Department of physics Xianyang Normal College Xianyang China

The X-ray spectra of Nb surface induced by Arq+ (q =1.,1.) ions with the energy range from 1. to 20 keV/q were studied by the optical spectrum technology. The experimental results indicate that the multi-electron excitation occurred as a highly charged Ar1.+ ion was neutralized below the metal surface. The K shell electron of Ar1.+ was excited and then de-excited cascadly to emit K X-ray. The intensity of the X-ray emitted from K shell of the hollow Ar atom decreased with the increase of projectile kinetic energy. The intensity of the X-ray emitted from L shell of the target atom Nb increased with the increase of projectile kinetic energy. The X-ray yield of Ar1.+ is three magnitude orders larger than that of Ar1.+.

关键词： highly charged ion hollow atom multi-electron X-ray

Predictions of synthesizing element 1.9 and 1.0

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Science china({1.,Mechanics & Astronomy) 2011年第S1期54卷 61-66页

作者： GAN ZaiGuo1. ZHOU XiaoHong1. HUANG MingHui1. FENG ZhaoQing1.& LI JunQing1.2 1.nstitute of modern {1., Chinese Academy of Sciences, lanzhou 730000,{3. 2School of Nuclear Science and Technology, lanzhou university, lanzhou 730000,{3. Institute of modern {1. Chinese Academy of Sciences Lanzhou China School of Nuclear Science and Technology Lanzhou University Lanzhou China

The evaporation residue cross sections of synthesizing superheavy nuclei Z=1.9, 1.0 are calculated by different sets of master equations with different dynamical variables. Two methods basically predicted similar results that the Ca induced hot fusion can 48 produce element 1.9 easier than produce 1.0, and the evaporation residue cross sections for 1.9 are detectable by current advanced techniques, while the evaporation residue cross sections are below 0.1.pb for producing element 1.0.

关键词： super heavy nuclei evaporation residue cross section master equations

Robustness and breakup of the spiral wave in a two-dimensional lattice network of neurons

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Science china({1.,Mechanics & Astronomy) 2010年第4期53卷 672-679页

作者： MA Jun 1.2, TANG Jun 2 , ZHANG AiHua 3.& JIA Ya 2 1.Department of {1., lanzhou university of Technology, lanzhou 73.050,{3. 2 Department of {1., Central{3. Normal university, Wuhan 43.079,{3. 3.College of Electrical and Information Engineering, lanzhou university of Technology, lanzhou 73.050,{3. Department of physics Lanzhou University of Technology Lanzhou China Department of physics Central China Normal University Wuhan China College of Electrical and Information Engineering Lanzhou University of Technology Lanzhou China

The robustness and breakup of spiral wave in a two-dimensional lattice networks of neurons are investigated. The effect of small- world type connection is often simplified with local regular connection and the long-range connection with certain probability. The network effect on the development of spiral wave can be better described by local regular connection and changeable long-range connection probability than fixed long-range connection probability because the long-range probability could be changeable in realistic biological system. The effect from the changeable probability for long-range connection is simplified by multiplicative noise. At first, a stable rotating spiral wave is developed by using appropriate initial values, parameters and no-flux boundary conditions, and then the effect of networks is investigated. Extensive numerical studies show that spiral wave keeps its alive and robust when the intensity of multiplicative noise is below a certain threshold, otherwise, the breakup of spiral wave occurs. A statistical factor of synchronization in two-dimensional array is defined to study the phase transition of spiral wave by checking the membrane potentials of all neurons corresponding to the critical parameters(the intensity of noise or forcing current)in the curve for factor of synchronization. The Hindmarsh-Rose model is investigated, the Hodgkin-Huxley neuron model in the presence of the channel noise is also studied to check the model independence of our conclusions. And it is found that breakup of spiral wave is easier to be induced by the multiplicative noise in presence of channel noise.

关键词： spiral wave factor of synchronization breakup multiplicative noise robustness

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 61.041. china 2. Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, lanzhou 730000, china 3. Resource and Environment School,{3., lanzhou 730000, 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 28.1.% under the permafrost environment degradation during recent 1. 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.