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Stochastic particle Acceleration in Blazar Jets

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chinese Journal of Astronomy and astrophysics 2002年第1期2卷 1-7页

作者： Jian-Cheng Wang Yunnan Observatory Chinse academy of Sciences, Kunming 650011 National Astronomical Observatories, chinese academy of Sciences, {3. 100012.United laboratory of Optical Astronomy chinese academy of Sciences Extragalactic astronomy Recei Yunnan Observatory Chinese Academy of Sciences Kunming 650011 []National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 []United Laboratory of Optical Astronomy Chinese Academy of Sciences

The bulk kinetic energy of jets can be dissipated via generating tur- bulen plasma waves. We examine stochastic particle acceleration in blazar jets to explain the emissions of all blazars. We show that acceleration of electrons by plasma turbulence wavs with a spectrum W(k) ~ k^(-4/{2. produces a nonthermal population of relativistic electrons whose peak frequency of synchrotron emission can fit the observational trends in the spectral energy distribution of all blazars. The plasma nonlinear processes responsible for the formation of turbulent spectrum are investigated. Increases in the ioteraction time of turbulent waves can produce a fiatter spectrum leading to efficient particle acceleration.

关键词： acceleration of paxticles - blazars: theory - plasma: turbulence - radiation mechanism: nonthermal

DNA DAMAGES INDUCED BY MIXED particle FIELD IRRADIATION

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DNA DAMAGES INDUCED BY MIXED PARTICLE FIELD IRRADIATION

全国作物生物技术与诱变技术学术研讨会

作者： Guo Huijun~1, Liu Luxiang~(1*), Zhao Linshu~1, Li Jiacai~2. Zhao Shirong~1, Wang Jing~1(1. key Lab of Agricultural Nuclear Technology & Aerospace Breeding, Ministry of Agriculture/Institute of Crop Science, chinese {2. of Agricultural Sciences, {3. 100081 2. Institute of high energy physics, CAS, {3. 100093.

＜正＞ Cosmic rays is one of the most important components in aerospace, which could be used to induce mutation in plants. However, little is known about its damage effect to DNA sequence. In this study, mixed high-energy {2.s generated by accelerator were used to simulate secondary cosmic rays （CR）, and the damage effects of plasmid DNA were preliminarily analyzed. PUC18 plasmid DNA was prepared and irradiated by mixed high-energy {2.s generated by accelerator to simulate secondary cosmic rays （CR）, including pion meson, muon, positron, electron, photon and proton, with the dosages of 68Gy, 12.Gy, 190Gy, 2.8Gy and 518Gy. Irradiated DNA and the non-irradiated control

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非重子冷暗物质粒子的研究进展

物理 2002年第9期31卷 577-580页

作者：盛祥东何会林戴长江中国科学院高能物理研究所宇宙线与高能天体物理重点实验室北京100039

暗物质问题目前已受到物理学界的高度关注 ,因为这一课题的研究和进展 ,将直接影响到粒子物理、天体物理和宇宙学的发展方向 .当前世界上已有一些大的实验组正在开展这方面的研究工作 ,并已取得了一定的结果 ;文章重点介绍两个重要的探... 详细信息

暗物质问题目前已受到物理学界的高度关注 ,因为这一课题的研究和进展 ,将直接影响到粒子物理、天体物理和宇宙学的发展方向 .当前世界上已有一些大的实验组正在开展这方面的研究工作 ,并已取得了一定的结果 ;文章重点介绍两个重要的探测实验 ,即中意合作DAMA组 (DarkMatterGroup) 10 0kgNaI(Tl)探测器阵列实验和美国的CDMS(ColdDarkMatterSearch)实验组的低温探测器实验 .详细介绍了DAMA实验的物理分析方法及其实验结果 ,并同CDMS实验结果进行了相应的比较 .

关键词：非重子冷暗物质暗物质年调制效应弱作用重粒子天体物理学 DAMA实验

Size-dependent translocation pattern,chemical and biological transformation of ferric oxide nanoparticles in the central nervous system

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Size-dependent translocation pattern,chemical and biological...

Analysis of heavy-ion-induced DNA strand breaks in plasmid pUC18

中国毒理学会第三届中青年学者科技论坛暨2.11年全国前列腺药理毒理学研讨会

作者： Bing Wang,~+ Ming Li,~+ Yun Wang,~+ Meng Wang,~+ Hong Ouyang,~+ Jing Zhang,Dong L. Chen,Zhi F.Chai,~+ Wei Y.Feng,~(+*)and Yu L.Zhao~(+*) + laboratory for Bio-Medical Effects of Nanomaterials and Nanosafety and key laboratory of Nuclear Analytical Techniques,Institute of {3. energy physics,chinese academy of Sciences,beijing 100049,china beijing Synchrotron Radiation Facility,Institute of {3. energy physics,beijing 100049, china

The toxic effects or biomedical functions of nanoparticles largely depend on their translocation ***,because of a large number of variable parameters of nanoparticles,experimental measurements of each type of nanoparticles in vivo become a huge work and almost ***,establishing theoretical models for rapid analyses will be beneficial to both safety estimation and application of *** the present study,the size-dependent translocation mode and biological fate of intranasally instilled FeO nanoparticles(40 nm and 2.0 nm)in CNS were *** nanoparticle translocation in different parts of brain at 4h,12.,2.h,3.,7d,and 3.d were quantified using ICP-MS technique.A biexponential model(correlation coefficient r=0.98～0.99)was satisfactory to describe the particokinetic translocation behavior of FeO nanoparticles in *** found a size-dependent translocation pattern and a size-sensitive time-window(4-72.h)of the nanoparticles in the brain,which are most significant in toxic concerns of nanoparticles in the *** synchrotron-based techniques such as microbeam X ray fluorescence(SR-μXRF) and near-edge X-ray absorption spectroscopy(XANES)were then used to map the spatial microdistribution and to identify the chemical forms of the nanoparticles in brain,respectively. The SR-μXRF images showed the 40 nm-FeO particles more widely distributed in brain regions than the large FeO particle *** XANES results indicate that the presence of chemical speciation of the FeO nanoparticle(～15%)and protein-complex like apotransferrin-FeO(～16%)in brain,implying that self-coating of FeO nanoparticles occurred with transferrin in *** but not the least,all the findings suggest size-sensitive manners of nanoparticles in brain,the smaller one possesses evident detention properties in the CNS *** larger one.

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湖南农业大学学报（自然科学版） 2007年第S1期33卷 242-页

作者： GUO Hui-jun1,LIU Lu-xiang1,LI Jia-cai2.ZHAO Kui3.SUI Li3.ZHAO Lin-shu1,ZHAO Shi-rong1(1.The National {2. Facility for Crop Gene Resources and Genetic Improvement,institute of Crop Science,chinese academy of Agricultural Sciences,{3. 100081,china 2.Institute of high energy physics,chinese academy of Sciences,{3. 100093.china 3.Department of Nuclear physics,china Institute of Atomic energy,{3. 102.13.china)

Plasmid DNA was irradiated or implanted by mixed particle field(CR) or lithium-ion-beam to detect strand *** primary results showed that mixed particle field could induce single and double strand breaks with positive linear-dose-effects;most of sequence changes induced by CR were point ***-ion-beam could induce strand breaks also,but it was only at dose of 2.Gy.

关键词： DNA Analysis of heavy-ion-induced DNA strand breaks in plasmid pUC18 CR

Size effects in lithium ion batteries

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chinese physics B 2016年第1期25卷 51-57页

作者：姚胡蓉殷雅侠郭玉国 CAS key laboratory of Molecular Nanostructure and Nanotechnology Institute of ChemistryChinese Academy of SciencesBeijing 100190China University of chinese academy of Sciences Beijing 100049China Shandong Wina Green Power Co.Ltd. Shouguang 262705China

Size-related properties of novel lithium battery materials, arising from kinetics, thermodynamics, and newly discov- ered lithium storage mechanisms, are reviewed. Complementary experimental and computational investigations of the use of the size effects to modify electrodes and electrolytes for lithium ion batteries are enumerated and discussed together. Size differences in the materials in lithium ion batteries lead to a variety of exciting phenomena. Smaller-particle materials with highly connective interfaces and reduced diffusion paths exhibit higher rate performance than the corresponding bulk materials. The thermodynamics is also changed by the higher surface energy of smaller particles, affecting, for example, secondary surface reactions, lattice parameter, voltage, and the phase transformation mechanism. Newly discovered lithium storage mechanisms that result in superior storage capacity are also briefly highlighted.

关键词： lithium ion batteries size effects experiment calculation

小角x射线散射法研究甲基改性氧化硅凝胶的双分形结构

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物理学报 2003年第2期52卷 442-447页

作者：徐耀李志宏范文浩吴东孙予罕王俊董宝中中国科学院山西煤炭化学研究所煤转化国家重点实验室太原030001 中国科学院高能物理研究所同步辐射国家实验室北京100039

以正硅酸乙酯 [Si(OC2.H5) 4,TEOS]和甲基三乙氧基硅烷 [CH3.i(OC2.H5) 3.MTES]为前驱体 ,通过共水解法和两步法制备出两种不同的甲基改性氧化硅凝胶 ,在北京同步辐射光源 (BSRF)小角x射线散射 (SAXS)站测量了凝胶的散射强度 ,计算了凝... 详细信息

以正硅酸乙酯 [Si(OC2.H5) 4,TEOS]和甲基三乙氧基硅烷 [CH3.i(OC2.H5) 3.MTES]为前驱体 ,通过共水解法和两步法制备出两种不同的甲基改性氧化硅凝胶 ,在北京同步辐射光源 (BSRF)小角x射线散射 (SAXS)站测量了凝胶的散射强度 ,计算了凝胶的平均粒径、两相间比表面积等参数 ,在此基础上分析了凝胶的分形特征 ,发现存在两个尺度上的分形结构 ,分别对应于从SiO2.原生颗粒到一次团聚体和从一次团聚体到簇团两种尺度 .辅以透射电子显微镜 (TEM)观测 ,证实由两种方法获得的凝胶具有非常不同的微观结构 .实验证明 ,利用SAXS技术研究甲基改性凝胶的分形特征是获得凝胶微观结构的有力工具 .

关键词：甲基改性凝胶氧化硅小角x射线散射 SAXS 双分形结构散射强度

Magnetic characterization of noninteracting,randomly oriented,nanometer-scale ferrimagnetic particles

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Magnetic characterization of noninteracting,randomly oriente...

烧结程度对CaO固硫反应转化率及动力学参数的影响

中国科学院地质与地球物理研究所第十届(2.10年度)学术年会

作者： Changqian Cao,Lanxiang Tian,Qingsong Liu,Weifeng Liu,Guanjun Chen, and Yongxin Pan 1 Paleomagnetism and Geochronology laboratory,key laboratory of the Earth’s Deep Interior,Institute of Geology and Geo{3.,chinese academy of Sciences,beijing,china. 2.Also at France-china Bio-Mineralization and Nano-Structures laboratory,Institute of Geology and Geo{3.,chinese academy of Sciences,beijing,china. 3.Also at Graduate University of chinese academy of Sciences,beijing, china. 4 State key laboratory of Microbial Technology,School of Life Sciences,Shandong University,Jinan,china.

[1]Studying the magnetic properties of ultrafine nanometer-scale femmagnetic particles (<10 nm)is vital to our understanding of superparamagnetism and its applications to environmental magnetism,biogeomagnetism,iron b...

[1]Studying the magnetic properties of ultrafine nanometer-scale femmagnetic particles (particle magnetostatic interactions and unknown size *** resolve these problems,we synthesized magnetoferritins using the recombinant human H chain ferritin(HFn). These femmagnetic HFn were further purified through size exclusion chromatography to obtain monodispersed ferrimagnetic *** electron microscopy revealed that the purified ferrimagnetic HFn are monodispersed and each consists of an iron oxide core(magnetite or maghemite)with an average core diameter of {2.9±1.1 nm imbedded in an intact protein *** R value of the Wohlfarth-Cisowski test measured at 5 K is 0.5,indicating no magnetostatic *** saturation isothermal remanent magnetization acquired at 5 K decreased rapidly with increasing temperature with a median unblocking temperature of 8.2.*** preexponential frequency factor f determined by AC susceptibility is(9.2.7.9)×*** extrapolated M/M and B/B at 0 K are 0.5 and 1.12.respectively,suggesting that the ferrimagnetic HFn cores are dominated by uniaxial *** calculated effective magnetic anisotropy energy constant K=1.2.10 J/m,which is larger than previously reported values for bulk magnetite and/or maghemite or magnetoferritin and is attributed to the effect of surface *** data provide useful insights into superparamagnetism as well as biomineralization of ultrafine ferrimagnetic particles.

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燃料化学学报 2001年第3期29卷 273-276页

作者：武增华寇鹏杨海波陈昌和清华大学化学系清华大学热能系北京100084

The conversion and kinetic parameters of desulfurizors of CaO of different particle agglomeration degree are investigated with themogravimetric method (TG). The results showed that the CaO particle agglomeration degree increases when CaO calcined temperature or time increases. The dusulfurizors that have {2.er particle agglomeration degree have low conversion in the desulfurization reaction. The kinetic behavior of desulfurization can be explained by a grain model. The activity energies of suface reaction (E a) and of product layer diffusion (E p) were determined by using the grain model. The overall rates of desulfurization are controlled initially by surface chemical reaction, and then shift to product layer diffusion control. The activity energy of surface reaction (E a) enhances when the CaO particle agglomeration degree increases.

关键词：烧结固硫反应动力学煤燃烧氧化钙转化率固硫剂环境保护活化能