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Defects in Fast-Neutron Irradiated Nitrogen-Doped Czochralski Silicon after Annealing at High Temperature

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Journal of Rare Earths 2006年第z1期24卷 91-93页

作者： Liu Lili Li Yangxian Ma Qiaoyun Chen Guifeng Sun yong Yang shuai School of Material Science and Engineering Hebei University of TechnologyTianjin 300130China

Fast-neutron irradiated nitrogen-doped Czochralski silicon(NCZ-Si)was annealed at 1100℃for different time,then FTIR and optical microscope were used to study the behavior of *** is found that[Oi]increase at the early stage then decrease along with the increasing of anneal *** density induced-defects can be found in the cleavage *** comparing NCZ-Si with Czochralski silicon(CZ-Si),[Oi]in NCZ-Si decrease more after anneal 24 h.

关键词： nitrogen-doped Czochralski silicon(NCZ-Si) neutron irradiation oxygen precipitation FTIR

Preparation of sulphonate-containing core/shell latex particles via seeded emulsion copolymerization

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Chinese Chemical Letters 2010年第10期21卷 1259-1262页

作者： Ji shuai Wang Wei Deng Yun shen Chen Cheng You Kan Department of Chemical Engineering and Key Laboratory of Advanced Materials of Ministry of Education Tsinghua University Belting 100084 China

In this study, P（St-MAA） seed latex particles were first prepared via soap-free emulsion polymerization of styrene （St） and methacrylic acid （MAA）, then the seed particles were allowed to swell with St at room temperature, and the P（St-MAA）/P（St- NaSS） core/shell latex particles were then synthesized via seeded emulsion copolymerization of St and sodium styrene sulphonate （NaSS） using AIBN as initiator in the presence of N,N^-methylenebisacrylamide （BAA, water-soluble crosslinker）. Results showed that the polymerization could be carried out smoothly when the ratio of BAA to total monomers was less than 3 mol%, the narrow dispersed P（St-MAA） seed particles with the diameter of 150 nm and the P（St-MAA）/P（St-NaSS） core/shell latexes with the particle size of about 200 nm were synthesized. When the 25/75 mole ratio of NaSS/（St ＋ MAA） and 2 tool% of BAA were used in the seeded emulsion polymerization, the resulted P（St-MAA）/P（St-NaSS） latex product showed a low weight loss after water extraction, and the NaSS unit content in the whole particle and in the shell reached 11.7 mol% and 34.6 mol%, resoectivelv.

关键词： seeded emulsion polymerization Sulphonate-containing particles Sodium styrene sulphonate N,N^-Methylenebisacrylamide

Resistance spot welding of Ti_(40)Zr_(25)Ni_3Cu_(12)Be_(20) bulk metallic glass:experiments and finite element modeling

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Rare Metals 2017年第2期36卷 123-128页

作者： Gang Wang yong-Jiang Huang Deodat Makhanlall Jun shen School of Mechanical and Automotive Engineering Anhui Polytechnic University School of Materials Science and Engineering Harbin Institute of Technology

The use of resistance spot welding（RSW）technology for joining Ti40Zr25Ni3Cu12Be20 metallic glass was *** microstructure obtained from the welded BMG sample was *** without precipitates was prepared with welding current of 5.0 kA for 2cycles.A fully coupled thermal-electrical-mechanical finite element model（FEM） was developed to complement the experimental *** simulated results agree well with the *** effects of key process parameters such as welding current and welding time on the evolvement and microstructure of the weldment were determined and ***,the critical cooling rate for preserving the amorphous state in the weld fusion zone is determined to be approximately 1×10^3 K·s^-1.

关键词： Metallic glasses Simulations Resistance spot welding Cooling rate

Mental healthcare for psychiatric inpatients during the COVID-19 epidemic

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General Psychiatry 2020年第2期33卷 64-65页

作者： shen Li yong Zhang Department of Psychiatry College of Basic Medical SciencesTianjin Medical UniversityTianjinChina Department of Bipolar Disorder Tianjin Anding HospitalTianjinChina

During this 2019 coronavirus disease(COVID-19)pneumonia epidemic,some experts have expressed concern for the mental healthcare of different types of population ***,hospitalised patients with severe mental illness are seemingly *** patients are still a vulnerable group who need to obtain more attention and respect,particularly during the COVID-19 outbreak in *** this commentary,we briefly introduce the situation of hospitalized patients with severe mental illness and suggest some effective measures that should be rapidly undertaken to reverse current challenges.

关键词： epidemic patients China.

New Version of the CMA-GFS Dynamical Core Based on the Predictor–Corrector Time Integration Scheme

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Journal of Meteorological Research 2023年第3期37卷 273-285页

作者： Xueshun shen yong SU Hongliang ZHANG Jianglin HU CMA Earth System Modeling and Prediction Centre China Meteorological Administration(CMA)Beijing 100081 State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesChina Meteorological AdministrationBeijing 100081

The operational numerical weather prediction system established by the China Meteorological Administration(CMA),based on the Global/Regional Assimilation and Prediction System(GRAPES)model,adopts the classical semi-implicit semi-Lagrangian(SISL)time integration *** paper describes a major upgrade to the dynamical core of the CMA global forecast system(CMA-GFS),which was successfully incorporated into operation in *** the upgrade,the classical SISL is further developed into a predictor–corrector scheme,a three-dimensional(3D)reference profile instead of the original isothermal reference profile is applied when implementing the semi-implicit algorithm,and a hybrid terrain-following vertical coordinate system is also *** new version of the dynamical core greatly improves the model performance,the time integration reaches second-order accuracy,the time step can be extended by 50%,and the efficiency is greatly improved(by approximately 30%).Atmospheric circulation simulation is systematically improved,and deviations in temperature,wind,and humidity are *** new version of the dynamical core provides a solid foundation for further development of the entire operational system of the CMA.

关键词： Global/Regional Assimilation and Prediction System(GRAPES) China Meteorological Administration global forecast system(CMA-GFS) predictor-corrector three-dimensional(3D)reference profile

A method for computing unsupported roof distance in roadway advancement and its in-situ application

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International Journal of Mining Science and Technology 2016年第4期26卷 551-556页

作者： Chen yong Bai Jianbiao Yan shuai Hao shengpeng Dao Viet Doan State Key Laboratory of Coal Resource and Safe Mining Key Laboratory of Deep Coal Resource Mining Ministry of Education of China China University of Mining and Technology Xuzhou 22116 China Hanoi University of Mining and Geology Hanoi 10000 Viet Nam

A reasonable unsupported roof distance(URD) when advancing underground coal mine roadways can contribute greatly to safe and rapid roadway development.A mechanical model of the roof,using the relationship between the roof stress distribution and URD,obtained by the difference method,and roof stability according to the in-situ roof stress and rock mass strength was *** subsequently designed a proper range of URD,developed a testing method of URD with the function of mining protection,evaluated roof stability through analyzing the test data and then determined a reasonable *** the factors of the geological conditions,the immediate roof stability and the efficiency of the labor arrangement system,the URD of the advancing roadway of 9802 working face in Zhangshuanglou coal mine was determined to be 6 m using the proposed *** results show that,when a 2 m length of roadway was reinforced by temporary support and high pre-stressed bolt support after the roadway advancement of 6 m per cycle,the speed and the security of the roadway development can be achieved and the advance rate can reach more than 400 m per month.

关键词： Unsupported roof distance (URD)Roadway advancement Difference method Roof stress Drivage per cycle Unsupported roof distance test

High-Order Dispersion Coefficients for Alkali-metal Atoms

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Communications in Theoretical Physics 2013年第7期60卷 73-79页

作者： KANG shuai DING Chi-Kun CHEN Chang-yong WU Xue-Qing School of Physics and Mechanical & Electrical Engineering Zunyi Normal College Zunyi 563002 China Department of Physics and Information Engineering Hunan Institute of Humanities Science and Technology Loudi 417000 China School of Physics and Electronics Science Guizhou Normal University Guiyang 550001 China

High-order dispersion coefficients C9, C11, C12, and C13 for the ground-state alkali-metals were calculated by combining the 1-dependent model potential of alkali-metal atoms and linear variation method based on B-spl... 详细信息

关键词： dispersion coefficient alkali-metal atom B-spline polarizability

A convenient synthesis of 6-demethoxycapillarisin

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Chinese Chemical Letters 2007年第4期18卷 407-408页

作者： Yuan Feng Tong shuai Chen yong Hao Cheng Song Wu Institute of Materia Medica Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100050 China

A convenient and effective method for the synthesis of 6-demethoxycapillarisin was described. The highlight was involved in a simple access to the key intermediate 2-ethylthio-5,7-dimethoxy-4H-chromen-4-one from the i... 详细信息

关键词： Synthesis 6-Demethoxycapillarisin Chromone

STUDY AND APPLICATION OF STEADY FLOW AND UNSTEADY FLOW MATHEMATICAL MODEL FOR CHANNEL NETWORKS

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Journal of Hydrodynamics 2007年第5期19卷 572-578页

作者： ZHANG Ming-liang shen yong-ming State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024 China

Based on the Preissmann implicit scheme for the one-dimensional Saint-Venant equation, the mathematical model for one-dimensional fiver networks and canal networks was developed and the key issues on the model were expatiated particularly in this article. This model applies the method of three-steps solution for chaunel-junction-channel to simulate the river networks, and the Gauss elimination method was used to calculate the sparse matrix. This model was applied to simulate the tree-type irrigation canal networks, complex looped channel networks and the Lower Columbia Slough networks. The results of water level and discharge agree with the data from the Adlul and field data. The model is proved to be robust for simulating unsteady flows in river networks with various degrees of complex structure. The calculated results show that this model is useful for engineering applications in complicated river networks. Future research was recommended to focus on setting up ecological numerical model of water quality in river networks and canal networks.

关键词： Preissmann implicit scheme canal networks and river networks unsteady flow ecological numerical model