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Determination of Young's modulus by nanoindentation

Science china(Technological sciences) 2004年第4期47卷 398-408页

作者： MA Dejun1, Chung Wo Ong2. LIU Jianmin1 & HE Jiawen3 1. Surface Engineering Research institute, CMES, beijing 100072.{2. 2. Department of Applied physics and Materials Research Center, The Hong Kong Polytechnic University, Hong Kong,{2. 3. State key laboratory for Mechanical Behavior of Materials, Xian Jiaotong University, Xian 710049,{2. 1. Surface Engineering Research institute CMES 100072 Beijing China 2. Department of Applied physics and Materials Research Center The Hong Kong Polytechnic University Hong Kong China 3. State key laboratory for Mechanical Behavior of Materials Xi’an Jiaotong University 710049 Xi’an China

A methodology for determining Youngs modulus of materials by non-ideally sharp indentation has been developed. According to the principle of the same area-to-depth ratio, a non-ideally pyramidal indenter like a Berkovich one can be approximated by a non-ideally conical indenter with a spherical cap at the tip. By applying dimensional and finite element analysis to the non-ideally conical indentation, a set of approximate one-to-one relationships between the ratio of nominal hardness/reduced Youngs modulus and the ratio of elastic work/total work, which correspond to different tip bluntness, have been revealed. The nominal hardness is defined as the maximum indentation load divided by the cross-section area of the conical indenter specified at the maximum indentation depth. As a consequence, Youngs modulus can be determined from a nanoindentation test only using the maximum indentation load and depth, and the work done during loading and unloading processes. The new method for determining Youngs modulus is referred to as pure energy method. The validity of the method was examined by performing indentation tests on five materials. The experimental results and the standard reference values are in good agreement, indicating that the proposed pure energy method is a promising substitution for the most widely used analysis models at present.

关键词： Young's modulus, nanoindentation, nominal hardness, indentation work.

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Spectral Feature analysis of Semiconductor Thin Disk Laser

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光机电信息 2007年第12期24卷 19-25页

作者： (HE Chun-feng1, QIN Li2. LI Jun1, CHENG Li-wen1, LIANG Xue-mei1, NING Yong-qiang2. WANG Li-jun2.1. key Laboratary of Excited State Processes, Changchun institute of Optics, Fine Mechanics and {2., chinese academy of sciences,Changchun 130033, china Graduate School of the chinese academy of sciences, beijing 100049, china 2. key Laboratary of Excited State Processes, Changchun institute of Optics, Fine Mechanics and {2., chinese academy of sciences, Changchun 130033,{12..) key Laboratary of Excited State Processes Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of SciencesChangchun 130033 China Graduate School of the chinese academy of sciences Beijing 100049 China key Laboratary of Excited State Processes Changchun Institute of OpticsFine Mechanics and Physics Chinese Academy of Sciences Changchun 130033China

The semiconductor thin disk laser is a new type of semiconductor laser. This work gives the basic operation function of the semiconductor disk laser, and analyses the heat effect by the experimentally measured photoluminescence spectrum of the laser chip at different pump power and different temperatures. We can see that: with increasing pump power, the thermal effect of the gain material becomes seriously and causes the saturation of carrier lifetime, so the electron-hole pair created in the absorbtion layer has no enough time to rate to one of the wells, and the non-radiative recombination happens in the barrier. When the thermal effect becomes stronger, the chip will be not lasing. This phenomenon is from the smaller energy offset between barrier and quantum well. We optimize the original structure design and experimental technology. A non-absorbing AlGaAs layer which is transparent to the pumping and laser wavelength is added to confine the carriers in the quantum wells. At the same time a DBR with double reflecting band is induced to improve the absorbing efficiency of the pumping light. The single QW is replaced by the three narrow QWs. This three QWs structure can add the quantum state of QW, increase the recombination probability of carriers in the QWs and reduce the heat effect. The chemical etching equipment is also improved to control the surface unevenness to be within 50 nm.

关键词： thin disk laser heat effect PL spectrum, active region heat removal gain barrier spectral shift

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Proton induced X-ray emission (PIXE) analysis of sources of porcelain body of Ru Guan and Jun Guan porcelains

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Science china(physics,Mechanics & Astronomy) 2006年第4期49卷 411-420页

作者： LI Guoxia1, ZHAO Weijuan1, LI Rongwu2. SUN Hongwei1, GUO Min1, WANG Yanfang1, LIU Hui1, ZHAO Qingyun3, SUN Xinmin3, ZHAO Wenjun3 & CHENG Huansheng4 1. Faculty of Physical Engineering, Zhengzhou University, Zhengzhou 450052. china 2. Department of physics, {2. Normal University, {2. 100875, china 3. institute of Cultural Relic and Archaeology of Henan Province, Zhengzhou 450000, china 4. institute of Modern physics, Fudan University, Shanghai 2.0433, china Faculty of Physical Engineering Zhengzhou University Zhengzhou 450052 China Department of physics Beijing Normal University Beijing 100875 China institute of Cultural Relic Archaeology of Henan Province Zhengzhou 450000 China institute of Modern physics Fudan University Shanghai 200433 China

34 samples of Ru Guan porcelain body and 50 samples of Jun Guan porcelain body (both kinds being in different body colors) were selected with the purpose of finding out the source of raw materials and their classification relationship so as to search for ways of non-destructive discrimination. Proton induced X-ray emission (PIXE) has been applied to these samples to determine their chemical elements. The data of seven major chemical elements collected from these samples were further studied through fuzzy cluster analysis. Results indicate that the origin of raw materials of Jun Guan porcelain body samples is comparatively more concentrated in certain places, while that of Ru Guan porcelain body samples is scattered about. The places of origin of raw materials of the majority of Ru Guan and Jun Guan porcelain body samples have something in common, but some differences still exist. It might be an important way for non-destructive discrimination among Ru Guan and Jun Guan porcelains by combining PIXE with fuzzy cluster analysis.

关键词： Ru Guan and Jun Guan porcelain, source of porcelain body, PIXE, fuzzy cluster analysis, non-destructive discrimination.

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DNA DAMAGES INDUCED BY MIXED PARTICLE FIELD IRRADIATION

DNA DAMAGES INDUCED BY MIXED PARTICLE FIELD IRRADIATION

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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/{2. of Crop Science, chinese academy of Agricultural sciences, beijing 100081 2. {2. of high energy physics, CAS, beijing 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 particles 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 particles 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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Investigation of Defects Induced by Helium and Hydrogen Implantation in CLAM Steel by a Slow Positron Beam

Investigation of Defects Induced by Helium and Hydrogen Impl...

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9th International Conference on Computer Simulation of Radiation Effects in Solids

作者： J.Qiu~1 Y.Xin~1 X.Ju~(1*) L.P.Guo~2.B.Y.Wang~3 Y.R.Zhong~3 Q.Y.Huang~4 Y.C.Wu~4 1 Department of physics University of Science and Technology beijing beijing 100083 china 2.Accelerator laboratory School of physics Wuhan University Wuhan Hubei 430072.china 3 key laboratory of nuclear analysis techniques {12. of high energy physics chinese academy of sciences beijing 100049 china 4 {12. of Plasma physics chinese academy of sciences Hefei Anhui 2.0031 china

＜正＞The Reduced Activation Ferritic/Martensitic（RAFM） steel is considered as the primary candidate of structural material for both the ITER and the first fusion plant, and widely studied in the *** china Low Activ... 详细信息

关键词： CLAM Steel Ion Implantation Slow Positron Beam

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非重子冷暗物质粒子的研究进展

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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

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

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

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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 high energy physics,chinese academy of sciences,beijing 100049,china beijing Synchrotron Radiation Facility,institute of high 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,3d,7d,and 30d 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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A NOVEL STRUCTURE PHOTOTRANSISTOR CE-PTHPT

A NOVEL STRUCTURE PHOTOTRANSISTOR CE-PTHPT

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2.01 6～(th) International Conference on Solid-State and Integrated Circuit Technology

作者： Li Guohui Yang Ru Han Dejun Ji Chengzhou Du Shucheng Zhu EnjunZeng Yiping Zhou Junming The key laboratory of Beam Technology and Materials Modification of Ministry of Education {2. Normal University china institute of Low energy nuclear Physic {2. Normal University {2. china 100875institute of Semiconductors chinese {12. of sciences {2. china 100083institute of physics chinese {12. of sciences {2. china 100080yangru@***

＜正＞A phototransistor of CE-PTHPT（Punch-ThroughHeterojunction Phototransistor with Control Electrode）with novel emitter control electrode and wide band gapemitter has been *** devices were workingunder the depletion on the base *** base currentis nearly zero and the output noise current decreaseeventually so as to increase the optical gain *** are an i type layer between emitter and *** doped base *** isolated planardevice and decreased emitter area in this device.

关键词： phototransistor CE-PTHPT GaAlAs/GaAs polysilicon InGaAs/InP

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Study of some marine bivalves as the biomonitor candidates for environmental assessment of the Jiaozhou Bay by NAA and AAS

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nuclear Science and techniques 1998年第3期 25-28页

作者： Zhang Pei Qun, Qian Qin Fang, Hou Xiao Lin, Lu Xiang Li, Chai Zhi Fang ( institute of high {2. physics, the chinese academy of sciences, beijing 100080 ) Wang Wen Qi, Li Feng Lan and Dong Jin Hai ( institute of Oceanology, the Chine

１ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｅｄｉｓｔｒｉｃｔｏｆｔｈｅＪｉａｏｚｈｏｕＢａｙｉｎｔｈｅｅａｓｔｅｒｎＣｈｉｎａｉｓａｎｅｘａｍｐｌｅｏｆｈｉｇｈｌｙａｎｔｈｒｏｐｏｇｅｎｉｃｒｅｓｕｌｔｅｄｃｏｍｐｌｅｘｅｃｏ... 详细信息

１ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｅｄｉｓｔｒｉｃｔｏｆｔｈｅＪｉａｏｚｈｏｕＢａｙｉｎｔｈｅｅａｓｔｅｒｎＣｈｉｎａｉｓａｎｅｘａｍｐｌｅｏｆｈｉｇｈｌｙａｎｔｈｒｏｐｏｇｅｎｉｃｒｅｓｕｌｔｅｄｃｏｍｐｌｅｘｅｃｏｓｙｓｔｅｍｗｈｉｃｈｍｅｒｇｅｓ...

关键词： Biomonitor Marine bivalves Environmental assessment Neutron activation analysis Atomic absorption spectrometry

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

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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 key Facility for Crop Gene Resources and Genetic Improvement,institute of Crop Science,{2. academy of Agricultural sciences,beijing 100081,china 2.institute of high energy physics,{2. academy of sciences,beijing 100093,china 3.Department of nuclear physics,china institute of Atomic energy,beijing 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

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