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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, China 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

Simulating　Experimental　Investigation　on　the　Safety　of　nuclear　Heating　Reactor　in　Loss－of－Coolant　Accidents

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Journal of Thermal Science 1996年第4期5卷 285-291页

作者： Zhanjie Xu(institute of nuclear energy technology, Tsinghua University, Beijing, 100084, China) institute of nuclear energy technology Tsinghua University Beijing China

The 5MW low temperature nuclear heating reactor (NHR-5) is a new and advanced type of nuclear reactor developed by institute of nuclear energy technology (INET) of Tsinghua University of China in 1989. Its main loop is a thermal-hydraulic system with natural circulation. This paper studies the safety of NHR under the condition of loss-of-coolant accidents (LOCAs) by means of simulant experiments. First, the background and necessity of the experiments are presented, then the experimental system, including the thermal-hydraulic system and the data collection system, and similarity criteria are introduced. UP to now, the discharge experiments with the residual heating power (20% rated heating power) have been carried out on the experimental system. The system parameters including circulation flow rate, system pressure, system temperature, void fraction, discharge mass and so on have been recorded and analyzed. Based on the results of the experiments, the conclusions are shown as folios: on the whole, the reactor is safe under the condition of LOCAs, but the thermal vacillations resulting from the vibration of the circulation flow rate are disadvantageous to the internal parts of the reactor core.

关键词： nuclear heating reactor natural circulation LOCA safety.

Two-dimensional numerical simulation of hydrodynamic behaviors of drop covered with vapor film

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Science China(Technological Sciences) 2005年第2期48卷 180-190页

作者： DUAN Riqiang, JIANG Shengyao, ZHANG Youjie, JIA Haijun & YANG Xingtuan institute of nuclear.and new energy technology, Tsinghua University Advanced Reactor Engineering and Safety, Key Laboratory of MOE of China, Beijing 102201, China 1. institute of nuclear.and new energy technology Tsinghua University 102201 Beijing China 2. Advanced Reactor Engineering and Safety Key Laboratory of MOE of China 102201 Beijing China

The breakup of drop covered with vapor film is numerically simulated. The moving particle semi-implicit method is used to solve the 2-dimensional unsteady Navier-Stokes equations for drop, vapor and ambient fluid. The results show that vapor film suppresses the drop breakup and hence the critical Weber number increases with the increasing thickness of vapor film. The breakup process can be divided into two stages. The drop deformation and breakup mainly occur in the later stage. Three breakup mechanisms are unveiled, which are almost the same as that of drop breakup without vapor film except for the stronger Rayleigh-Taylor instability for drop with vapor film. Our simulation results are comparable with the previous experiments.

关键词： drop breakup, vapor film, numerical simulation, particle method, moving particle semi-implicit method.

Carbon emission permit allocation and trading

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Journal of Environmental Sciences 1999年第4期11卷 468-473页

作者： CHEN Wen\|ying, WU Zong\|xin (institute of nuclear energy technology, Tsinghua University, Beijing 100084, China) 清华大学核能技术设计研究院北京

Nowadays our earth is faced with grim challenge of global climate change. All countries should go into action jointly to mitigate climate change. Carbon emission permit allocation and trading are two important issues to realize global cooperation. In this paper two kinds of comprehensive carbon emission permit allocation methods not only considering equity but also efficiency were advanced. After the carbon permit price was determined, the trading situations in various regions or countries in the world and the global benefits gained from emission trading were expounded. Moreover, the impact of carbon emission permit trading on Chinas economy was analyzed.

关键词： climate change carbon permit allocation carbon permit trading comprehensive allocation method

Characterization of microarc oxidation coatings on pure titanium

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Rare Metals 2003年第1期22卷 42-48页

作者： XUE Wenbin, WANG Chao, Li Yongliang, and CHEN RuyiKey Laboratory for Beam technology and Materials Modification, institute of Low energy nuclear Physics, Beijing Normal University, Beijing 100875, China 北京师范大学射线束技术与材料改性教育部重点实验室北京 100875

Key Laboratory for Beam technology and Materials Modification, institute ofLow energy nuclear Physics, Beijing Normal UniversityThe morphology, composition, and phase structure of the oxide coatings produced on the surface ofpure titanium by alternating-current microarc discharge in aluminate solution were investigated byX-ray diffraction and scanning electron microscopy. The profiles of the hardness H and the elasticmodulus E in the coatings were determined using a nanoindentation method. The concentrationdistributions of Ti, Al, and O in the coating show that this coating over 30 mu m thick contains twolayers: an outer layer and an inner layer. The oxide coating is mainly composed of TiO_2 rutile andAl_2TiO_5 compounds. During oxidation, the temperature in the microarc discharge channel was veryhigh to make the local coating molten. From the surface to the interior of the coating, H and Eincrease gradually, and then reach maximum values of 9.78 GPa and 176 GPa respectively at a distanceof 7 mu m from the coating/titanium interface. They are also rather high near the interface.

关键词： pure titanium ceramic coating microarc oxidation microstructure nanoindentation

Microscopic Analysis of Inelastic Proton Scattering off ^(28)Si

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Chinese journal of nuclear physics 1995年第2期17卷 124-128页

作者： An Zhu(institute of nuclear Science and technology,Sichuan University,Chengdu 610064) Sichuan Univ Chengdu China

The elastic and inelastic scattering data of 22 MeV protons from 28Si havebeen *** measured differential cross sections were compared with microscop-ic DWBA calculations in which nuclear transition densities extracted from （e,e’） exper-iments were used directly.A density-dependent nucleon-nucleon effective interaction inthe low-energy region,Complex Effective Interaction with Gaussian form factor（CEG）,was applied in our *** problems associated were discussed.

关键词： Proton inelastic scattering Local momentum approximation Nucleonnucleon effective interaction

Free　radical　oxidation　of　spent　radioactive　organic　solvent

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Journal of Environmental Sciences 1997年第2期9卷 77-82页

作者： Ji Xiaoyuan, Zhao Bin institute of nuclear energy technology, Tsinghua University, Beijing 100084, China

The decomposition of radioactive Spent Organic Solvent (SOS) was conducted successfully in bench scale tests. The experiment results showed that TBP/OK can be decomposed under with in H 2O 2 Fe 2+ /TiO 2 H 2SO 4 systems under suitable H 2O 2 concentration, catalyst, temperature and pH. The free radical oxidation reaction mechanism using H 2O 2 under the action of the synergistic catalysis TiO 2/Fe 2+ was also discussed briefly.

关键词： spent organic solvent catalytic oxidation synergetic catalysis.

Kinetics of recovering germanium from lignite ash with chlorinating roasting methods

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Rare Metals 2008年第3期27卷 238-242页

作者： ZHU Guocai WANG Jingyan CHENG Zhuo ZHAO Yuna institute of nuclear.and new energy technology Tsinghua University Beijing 102201 China

A process of recovering Ge by chlorinating masting was put forward. GeCl4 was separated and recovered from lignite ash because of its low boiling point. Kinetic analysis indicates that the chlorinating roasting process fits with the unreacted-core shrinking model and the reaction rate equation corresponds to 1 - 2a/3 - （1 - a）2/3 = kt. The apparent activation energy Ea is calculated to be 22.36 kJ·mol^-1. The diffusion of product layer serves as the rate-controlling step in this process. When the roasting temperature is 250℃, the roasting time is 60 min, the con- centration of hydrochloric acid is 10 mol/L, and the ratio of liquid to solid is 10 （mHCl/ash = 10）, and 90% Ge in lignite ash can be recovered.

关键词： lignite ash germanium chlorinating roasting kinetics

RECOVERING RE FROM LEACHING LIQUOR OF RARE EARTH ORE BY EXTRACTION

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中国有色金属学会会刊：英文版 1995年第4期5卷 36-40页

作者： Chi Ru’an Xu Jingming He Peijiong Zhu Yongjun(institute of nuclear energy Technolegy,Tsinghua University,Beijing 100084) Tsinghua Univ Beijing China

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关键词： rare earth ore leaching solvent extraction