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Dark output characteristic of γ-ray irradiated CMOS digital image sensors

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Rare Metals 2002年第1期21卷 79-84页

作者： MENG Xiangti and KANG A iguo institute of Nuclear Energy Technology, Tsinghua University, beijing 100084,{2. institute of Nuclear Energy Technology Tsinghua University 北京 100084

The quality of dark output images from the CMOS (complementarymetal oxide semiconductor) black and white (B & W) digital imagesensors captured before and after γ-ray irradiation was studied. Thecharacteristic parameters of the dark output images captured atdifferent radiation dose, e.g. average brightness and itsnon-uniformity of dark out- put images, were analyzed by our testsoftware. The primary explanation for the change of the parameterswith the radi- ation dose was given.

关键词： CMOS digital image sensor gamma radiation dark output characteristic Si

Study of safety performance of the ^(2.1)Am fire alarm source

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Nuclear Science and Techniques 2000年第1期11卷 34-40页

作者： FENG Gen-Sheng (china institute of Afomic Eachs, {2. 102.1s) 中国原子能科学院北京 102413

The safety performance of 2.1Am fire alarm sources made by using powder metallurgical technology has been preliminarily studied, so as to determine an allowable maximum energy limit value of the alpha particles outgoing from this kind of sources in light of radiation safety and the present technology. The yielded results show that 2.1Am leak has not been found when the peak energy of the alpha energy spectrum of this kind of sources is less than 4.96 MeV.

关键词：镅2.1 火警源辐射源火灾监测安全性能

Experimental investigation of supersonic radiation propagation in low-density plastic and copper-doped foams

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Science china(Physics,Mechanics & Astronomy) 2005年第5期48卷 549-558页

作者： JIANG Shaoen1, XU Yan2. DING Yongkun1, LAI Dongxian2. ZHENG Zhijian1, HUANG Yixiang1, LI Jinghong2. SUN Kexu1, HU Xin1, ZHANG Wenhai1, YI Rongqing1, CUI Yanli1 & CHEN Jiusen1 1. National Key Laboratory of Laser Fusion, Laser Fusion Research Center, Mianyang 62.900, china 2. institute of Applied Physics and Computation Mathematics, {2., 100088, china National Key Laboratory of Laser Fusion Laser Fusion Research Center Mianyang 621900 China institute of Applied Physics and Computation Mathematics Beijing 100088 China

Eight beams of 0.35 μm laser with pulse duration of 1 ns and total energy of 2.kJ enter into a hohlraum to create intense X-ray radiation of 140 eV on the Shenguang ΙΙ laser facility. Plastic foam (C6H12. and copper-doped foam (C6H12.u0.394) with a density of 50 mg/cm3 are heated by X-ray radiation emitted from the hohlraum. The breakout time of the radiation wave is measured by a tri-chromatic streaked X-ray spectrometer (TCS) that consists of a set of three imaging pinholes and an array of three transmission gratings coupled with an X-ray streak camera (XSC). At one shot, the simultaneous measurements of the delay of the drive source and the radiation transport at two energies (2.0 eV, 840 eV) through the foam have been made for the first time. The experimental results indicate that the time delays vary with photon energies. With a transmission grating spectrometer (TGS), the spectra transmitting foams were measured, and the lower limit of the optical depth was measured. The radiation at energy of 2.0 eV propagates through plastic foam at a faster velocity, compared with the radiation at energy of 840 eV; while the results of copper-doped foam are reverse. The optical depth in the plastic foam is less than 1, and in the doped foam it is more than 1.

关键词： supersonic radiation wave, plastic foam, copper-doped foam, optical depth.

Constraints of f(R) gravity in Palatini approach with observational Hubble data

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Science china(Physics,Mechanics & Astronomy) 2011年第8期54卷 1378-1383页

作者： ZHAI ZhongXu & LIU WenBiao Department of Physics, institute of Theoretical Physics, beijing Normal University, beijing 100875, china beijing Normal University Department of Physics Institute of Theoretical Physics Beijing China (GRID:grid.20513.35) (ISNI:***)

We use the newly released observational H(z) data (OHD), the Cosmic Microwave Background (CMB) shift parameter, and the Baryon Acoustic Oscillation (BAO) measurements data to constrain cosmological parameters of f(R) gravity in Palatini formalism in which the f(R) form is defined as f(R) = R β/Rn. Under the assumption of a spatially flat FRW universe, we get the best fitting results of the free parameters (Ωm0, n). In the calculation, we marginalize the likelihood function over H0 by integrating the probability density P ∝ e-χ2.2.to obtain the best fitting results and the confidence regions in the Ωm0-n plane. The constraints results of (Ωm0, n) = (0.33, 0.41) by OHD only and (Ωm0, n) = (0.2., 0.08) by the combination of OHD+CMB+BAO both indicate that the universe goes through three last phases, i.e., radiation dominated, matter-dominated, and late time accelerated expansion without introduction of dark energy.

关键词： f(R) gravity OHD CMB BAO accelerating expansion dark energy

Temporal-spatial variations of euphotic depth of typical lake regions in Lake Taihu and its ecological environmental significance

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Science china Earth Sciences 2006年第4期49卷 431-442页

作者： ZHANG Yunlin1, 2. QIN Boqiang1, HU Weiping1, WANG Sumin1, CHEN Yuwei1 & CHEN Weimin1 1. Nanjing institute of Geography & Limnology, Chinese Academy of Sciences, Nanjing 2.0008, china 2. Graduate School of the Chinese Academy of Sciences, {2. 100039, china Nanjing institute of Geography & Limnology Chinese Academy of Sciences Nanjing China Graduate School of the Chinese Academy of Sciences Beijing China

By using the data of underwater irradiance measured in the different lakeregions of Lake Taihu during 1998—2.04 and total suspended solids (TSS), wind speeds of the total13 stations in typical lake regions during 1993—2.03, this paper analyzes the factors ofinfluencing on PAR (pho-tosynthetically available radiation) attenuation, euphotic depth, andpresents the temporal and spatial variations of euphotic depth of typical lake regions in LakeTaihu, and the spectral distributions of euphotic depth at station 2. The results show that theconcentration of TSS is the most important factor impacting PAR attenuation, followed by chlorophylla; chromophoric dissolved organic matter (CDOM) has little impact on the PAR euphotic depth. During1993—2.03, the mean yearly PAR euphotic depths of the typical lake regions ranged from 1.04 to1.95 m with a mean value of 1.35±0.2. m. The PAR euphotic depth fell into 3 spatial zone types:Type Ⅰ, the lowest, including the lake center and the inflows of rivers; Type Ⅱ, intermediate,including Meiliang Bay, Wulihu Lake and Gonghu Bay; Type Ⅲ, the greatest, including the East LakeTaihu; corresponding mean depths were approximately 1.1, 1.4, 2.0 m, respectively. The seasonalvariations of euphotic depths were not quite the same in different lake regions. In the lake center,the mean values of PAR euphotic depth in summer and autumn were significantly greater than those inwinter and spring; in the Meiliang Bay, winter means were significantly greater than in the otherthree seasons; in the East Lake Taihu, winter means were significantly less than in the other threeseasons. However, no distinct seasonal change was recorded in the Wulihu Lake, Gonghu Bay and theinflows of rivers. The spectral distributions of euphotic depth present a minimal value at the bluelight wave band of 400 nm, and a peak at the green light wave band of around 580 nm. In 1998 and1999, based on the seasonal many-day continuous measurements, the PAR euphotic depths at station 2.

关键词： lake taihu euphotic depth diffuse attenuation coefficient total suspendedsolid ecological

Effects of enriched environment on morphine-induced reward in mice

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Effects of enriched environment on morphine-induced reward i...

类泛素化修饰Neddylation的功能和调控机制研究进展

中国神经科学学会第四次会员代表大会暨第七届全国学术会议

作者： Zhi-wei XU,Bing HOU,Yan GAO,Fu-chu HE~*,Cheng-gang ZHANG~* beijing institute of {2. medicine,beijing 100850,china

＜正＞Drug addiction and abuse have now been extremely serious problems in our *** has been reported that environmental conditions play a crucial role in susceptibility to drug addiction in *** important paradigm termed "enriched environment（EE）" has been employed to assess environment-induced behavior ***,few studies have examined if whether enriched environment affects subsequent responsivity to drugs of *** this study,we investigated if an the enriched environment during postnatal development alters t morphine-induced reward in *** C57BL/6 mice of 3 weeks were housed in a standard environment（SE） or enriched *** in the standard environment were housed in the regular animal facility cages receiving water and food ad *** enriched environment consisted of a large cage with running wheels,tunnels,rubber balls and *** two months,the behavioral sensitization test,conditioned place preference（CPP） test and immunohistochemical detection of FosB-like proteins were examined to evaluate the behavioral and molecular effects of *** assess behavioral sensitization effect of morphine,mice were firstly habituated to the activity cages for two *** habituation,the mice were given 7 days of repeated injections of morphine（10 mg/kg,ip）.Animals were left undisturbed for 5 days and then treated with the same way as that at day *** assess the CPP effect of morphine,the mice were exposed to the CPP apparatus to assess initial preference for 2.days in an unbiased *** Tthe following day,mice were given either morphine（5 mg/kg,ip） conditioning in a counterbalanced *** the final day,the mice were placed in the apparatus and the difference in time spent in the drug paired environment before ＆ and after conditioning was *** detect the expression of FosB-like proteins,the mice were perfused and the brains were then removed,fixed and mounted in the cryostat to produce coronal sections for imm

关键词： Enriched environment Morphine Behavior sensitization Conditioned place preference FosB-like protein Drug abuse

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生物化学与生物物理进展 2009年第9期36卷 1089-1094页

作者：何珊张令强贺福初北京工业大学生命科学与生物工程学院北京100124 军事医学科学院放射与辐射医学研究所蛋白质组学国家重点实验室北京100850

NEDD8(neural precursor cell-expressed developmentally downregulated 8)分子是一类结构上与泛素相似的分子,参与蛋白质翻译后修饰,这一过程被称为***的发生机制与泛素化相似,需要E1、E2.E3介导的一系列酶促反应.Neddylation修饰在Cullin-Roc类泛素连接酶的活性调控中具有至关重要的作用,与泛素化研究相比,在真核细胞内仅发现了很少的能被Neddylation修饰的底物,Neddylation的生理功能也有待深入研究.

关键词：蛋白质翻译后修饰 Neddylation NEDD8 Cullin

Absolute radiometric calibration of CBERS-02.IRMSS thermal band

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Science china(Technological Sciences) 2005年第S2期48卷 72-90页

作者： ZHANG Yong1,2.3, GU Xingfa1,3,4, YU Tao1,3, ZHANG Yuxiang5, CHEN Liangfu1,3, LI Xiaoying1,2.3, LI Xiaowen1,3 & HE Liming6 1. State Key Laboratory of Remote Sensing Science, Jointly Sponsored by the institute of Remote Sensing Applications of Chinese Academy of Sciences and beijing Normal University, beijing 100101, china 2. Graduate University of Chinese Academy of Sciences, beijing 100039, china 3. The Center for National Spaceborne Demonstration, beijing 100101, china 4. Institut National de la Recherche Agronomique, Climat Sol Environnement, 84914 Avignon, France 5. National Satellite Meteorological Center, beijing 100081, china 6. State Environmental Protection Administration, beijing 10002., china State Key Laboratory of Remote Sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Graduate University of Chinese Academy of Sciences The Center for National Spa

Based on the laboratory calibration before launch of CBERS-02.IRMSS thermal infrared channel, the onboard blackbody calibration, the radiometric cross- calibration against TERRA MODIS corresponding channel and the in-flight field calibration at Lake Qinghai: water surface radiometric calibration test site of china on Aug. 17, 2.04 are carried out in this research. When making onboard blackbody calibration of CBERS-02.IRMSS, it is necessary to understand inside structures and light path in IRMSS camera and receive and process calibration blackbody signals at normal and high temperatures. Onboard blackbody calibration results of each detector are very important to relative radiometric calibration of images processing and absolute radiometric calibration of each detector. In-flight field calibration mainly contains field experiments, obtaining synchronous images, spectrum marching and MODTRAN radiative transmi- ssion computation. Radiometric cross-calibration of CBERS-02.IRMSS thermal band against TERRA MODIS selected 6 times synchronous images of two sensors passing through Lake Qinghai and Lake Taihu from August to December, 2.04 to compute the cross calibration data. Combining the in-flight field calibration and radiometric cross calibration data, the absolute radiometric calibration coefficients are calculated by the linear regression method. This new calibration model can obviously control the radiometric calibration uncertainties aroused by the single point method used in the in-flight calibration of CBERS-02.IRMSS, this kind of sensors cannot receive the cosmic background radiation. In this research, the radiometric calibration coefficients obtained through the linear regression model are 8.53 (gain, unit: DN/W m?2.r?1μm?1) and 44.92.(offset, unit: DN).

关键词： CBERS-02 IRMSS thermal band in-flight field calibration onboard blackbody calibration cross calibration.

THERMAL SHOCK OF SEMI-INFINITE BODY WITH MULTI-PULSED INTENSE LASER radiation

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Acta Mechanica Solida Sinica 2010年第2期23卷 175-180页

作者： Haiming Huang 1 Fang Su Yue Sun(institute of Engineering Mechanics,beijing Jiaotong University,beijing 100044,china) institute of Engineering Mechanics Beijing Jiaotong University Beijing China

In order to investigate the thermal shock and the heat conduction property of a target under multi-pulsed laser radiation, analytic expressions of both temperature and thermal stress fields in the target are deduced on the basis of the non-Fourier conduction law and the thermo-elastic theory. Taking a stainless steel target as an example, we can solve the analytic expressions under appropriate boundary conditions by using the finite difference method and MATLAB software, and then reveal the evolution law of both surplus temperaturt, and thermal stress in the target. The results indicate that the temperature curves in the target irradiated by a multi-pulsed laser take on a delayed character in different sections away from the boundary, which is only affected by its relaxation time. The front of the stress wave is very steep in the non-Fourier numerical solutions, which presents an obvious thermal shock, so it is necessary to consider the non-Fourier effect of semi-infinite body under the high energy laser radiation.

关键词： multi-pulsed laser non-Fourier effect thermal shock