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Polarization of GRB prompt emission and its application to POLAR’s data

Research in Astronomy and Astrophysics 2021年第3期21卷 43-56页

作者： mi-xiang Lan Xue-Feng Wu Zi-Gao Dai Center for Theoretical Physics and College of Physics Jilin UniversityChangchun 130012China Purple Mountain Observatory Chinese Academy of SciencesNanjing 210008China School of Astronomy and Space Science Nanjing UniversityNanjing 210093China Key Laboratory of Modern Astronomy and Astrophysics(Nanjing University) Ministry of EducationNanjing 210093China

Synchrotron emission polarization is very sensitive to the magnetic field ***,polarization of synchrotron emission with a mixed(SM)magnetic field in the gamma-ray burst(GRB)afterglow phase has been ***,we apply these SM models to the GRB prompt phase and compare their polarization properties with that of synchrotron emission in purely ordered(SO)magnetic *** find that the polarization properties in an SM model are very similar to these in a corresponding SO model(e.g.,synchrotron emission in a mixed magnetic field with an aligned ordered part(SMA)and synchrotron emission with a purely ordered aligned magnetic field(SOA)),only with a lower polarization degree(PD).We also discuss the statistical properties of the *** find PDs of the simulated bursts are concentrated around 25%for both SOA and synchrotron emission in a purely ordered toroidal magnetic field(SOT),while they can range from 0%to 25%for SMA and synchrotron emission in a mixed magnetic field with a toroidal ordered part(SMT),depending onξ_B value,i.e.,the ratio of magnetic reduction of the ordered magnetic field over that of random magnetic *** statistics,if PDs of majority GRBs are non-zero,then it favors SO and SM ***,if there are some bright GRBs with prominently lower PDs than that of the majority GRBs,it favors SOT(SMT)models;if all the bright GRBs have comparable PDs with the majority ones,it favors SOA(SMA)***,we apply our results to POLAR’s data and find that~10%time-integrated PDs of the observed bursts favor SMA and SMT models,and theξ_B parameter of these bursts is constrained to be around 1.135.

关键词： gamma-ray burst:general magnetic fields polarization radiation mechanisms:nonthermal

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Ultra-Pure Ferritic Stainless Steels-Grade,Refining Operation,and Application

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Journal of Iron and Steel Research International 2007年第4期14卷 24-30页

作者： YOU xiang-mi JIANG Zhou-hua LI Hua-bing School of Materials and Metallurgy Northeastern University Shenyang 110004 Liaoning China

The grades of ultra-pure ferritic stainless steels, especially the grades used in automobile exhaust system, were reviewed. The dependence of properties on alloying elements, the refining facilities, and the mechanism of the reactions in steel melts were described in detail. Vacuum, strong stirring, and powder injection proved to be effective technologies in the melting of ultra-pure ferritic stainless steels. The application of the ferritic grades was also briefly introduced.

关键词： ultra-pure ferritic stainless steel interstitial element stabilizing element automobile exhaust system SS-VOD VOD-PB VCR

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High Nitrogen Austenitic Stainless Steels Manufactured by Nitrogen Gas Alloying and Adding Nitrided Ferroalloys

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Journal of Iron and Steel Research International 2007年第3期14卷 63-68页

作者： LI Hua-bing JIANG Zhou-hua SHEN ming-hui YOU xiang-mi School of Materials and Metalllargy Northeastern University Shenyang 110004 Liaoning China

A simple and feasible method for the production of high nitrogen austenitic stainless steels involves nitrogen gas alloying and adding nitrided ferroalloys under normal atmospheric conditions. Alloying by nitrogen gas bubbling in Fe-Cr-Mn-Mo series alloys was carried out in MoSi2 resistance furnace and air induction furnace under normal atmospheric conditions. The results showed that nitrogen alloying could be accelerated by increasing nitrogen gas flow rate, prolonging residence time of bubbles, increasing gas/molten steel interfaces, and decreasing the sulphur and oxygen contents in molten steel. Nitrogen content of 0.69% in 18Crl8Mn was obtained using air induction furnace by bubbling of nitrogen gas from porous plug. In addition, the nickel-free, high nitrogen austenitic stainless steels with sound and compact macrostructure had been produced in the laboratory using vacuum induction furnace and electroslag remelting furnace under nitrogen atmosphere by the addition of nitrided alloy with the maximum nitrogen content of 0.81%. Pores were observed in the ingots obtained by melting and casting in vacuum induction furnace with the addition of nitrided ferroalloys and under nitrogen atmosphere. After electroslag remelting of the cast ingots, they were all sound and were free of pores. The yield of nitrogen increased with the decrease of melting rate in the ESR process. Due to electroslag remelting under nitrogen atmosphere and the consequential addition of aluminum as deoxidizer to the slag, the loss of manganese decreased obviously. There existed mainly irregular Al2O3 inclusions and MnS inclusions in ESR ingots, and the size of most of the inclusions was less than 5 um. After homogenization of the hot rolled plate at 1 150℃ × 1 h followed by water quenching, the microstructure consisted of homogeneous austenite.

关键词： nitrogen gas alloying nitrided ferroalloy high nitrogen austenitic stainless steel vacuum induction melting electroslag remelting

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Protecting healthcare personnel from 2019-nCoV infection risks:lessons and suggestions

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Frontiers of Medicine 2020年第2期14卷 229-231页

作者： Zhiruo Zhang Shelan Liu mi xiang Shijian Li Dahai Zhao Chaolin Huang Saijuan Chen School of Public Health Shanghai Jiao Tong University School of MedicineShanghai 200025China Department of Infectious Diseases Zhejiang Provincial Centre for Disease Control and PreventionHangzhou 310000China Department of Public Health SUNY College at Old WestburyOld WestburyNY 11568USA School of International and Public Affairs Shanghai Jiao Tong UniversityShanghai 200025China Department of Infectious Diseases Jinyintan HospitalWuhan 430030China Key Laboratory of Medical Genomics Shanghai Institute of HematologyNational Research Center for Translational MedicineRuijin Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghai 200025China

The outbreak of a novel coronavirus disease(COVID-19,caused by the 2019-nCoV infection)in December 2019 is one of the most severe public health emergencies since the founding of People’s Republic of China in *** personnel(HCP)nationwide are facing heavy workloads and high risk of infection,especially those who care for patients in Hubei ***,as of February 20,2020,over two thousand COVID-19 cases are confirmed among HCP from 476 hospitals nationwide,with nearly 90%of them from Hubei *** on literature search and interviews with some HCP working at Wuhan,capital city of Hubei,we have summarized some of the effective measures taken to reduce infection among HCP,and also made suggestions for improving occupational safety during an infectious disease *** experience and lessons learned should be a valuable asset for international health community to contain the ongoing COVID-19 epidemic around the world.

关键词： healthcare personnel COVID-19 infectious diseases

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Electric Field Stress Simulation of Plasma Membrane Under Steep Pulsed Electric Field

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高电压技术 2009年第5期35卷 1088-1092页

作者： YAO Chen-guo LUO Xiao LI Cheng-xiang mi Yan State Key Laboratory of Power Transmission Equipment & System Security and New Technology Chongqing University Chongqing 400044 China

The basic characteristic of electric field is that the substance in the field is in operation by the *** external electric fields,there is strong distribution of electric fields on the inside and outside surfaces of cell *** virtue of the difference of the permittivity among membrane,cytoplasm and extracellular medium,there must he electric field stress on the surface of the *** goal of the study is to research the irreversible electrical breakdown (IRE) mechanism of the malignant tumor cells under steep pulsed electric field (SPEF)from the views of *** field stress of plasma membrane under steep pulsed electric field is calculated and simulated both on malignant tumor cells and on the normal *** calculation results show that,in addition to a compressive stress normal to the membrane plane,transverse traction stresses are generated in the lateral plane of the *** lateral stress will reduce the membrane tension significantly,leading to electroporation and *** the same electric field strength,the transverse traction stress on malignant cell membrane is greatly larger than the one on normal cell ***,compared with the normal cells,the malignant tumor cells are more sensitive under the steep pulsed electric ***,steep pulsed electric field can selectively destroy the malignant tumor cells,which proved the safety of treating malignant tumors by steep pulsed electric field.

关键词：电场压脉冲电场高压电横向牵引电压

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钢筋位置对混凝土断裂参数的影响

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水利学报 2012年第S1期43卷 46-51页

作者：米正祥胡少伟南京水利科学研究院材料结构研究所江苏南京210029

为了研究钢筋位置对混凝土起裂韧度与失稳韧度等断裂参数的影响,以及钢筋在混凝土裂缝扩展过程中的限裂作用,设计制作了4组在不同位置布置钢筋的三点弯曲试件,对其进行了断裂性能试验研究,并给出了利用叠加原理求解钢筋混凝土试件的起... 详细信息

为了研究钢筋位置对混凝土起裂韧度与失稳韧度等断裂参数的影响,以及钢筋在混凝土裂缝扩展过程中的限裂作用,设计制作了4组在不同位置布置钢筋的三点弯曲试件,对其进行了断裂性能试验研究,并给出了利用叠加原理求解钢筋混凝土试件的起裂韧度与失稳韧度的计算公式。研究结果表明:在加载过程中,钢筋混凝土试件的P-CMOD曲线将出现两个荷载峰值点,其裂缝扩展过程可以用双K断裂判据来描述;起裂韧度与钢筋位置无关,可以作为材料的断裂参数;而失稳韧度受钢筋位置的影响,且钢筋未贯穿裂缝时的失稳韧度远大于钢筋贯穿裂缝时的失稳韧度,这为实际工程中锚杆加固提供了有效的试验依据。

关键词：钢筋混凝土钢筋位置断裂韧度裂缝扩展过程

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Fast Electrical Detection of Carcinoembryonic Antigen Based on AlGaN/GaN High Electron Mobility Transistor Aptasensor

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Chinese Physics Letters 2017年第9期34卷 87-90页

作者： xiang-mi Zhan Quan Wang Kun Wang Wei Li Hong-Ling Xiao Chun Feng Li-Juan Jiang Cui-Mei Wang Xiao-Liang Wang Zhan-Guo Wang Key Lab of Semiconductor Materials Science Institute of Semiconductors Chinese Academy of Sciences Beijing 100083 School of microelectronics University of Chinese Academy of Sciences Beijing 100049 Beijing Key Laboratory of Low Dimensional Semiconductor Materials and Devices Beijing 100083

As one of the most important tumor-associated antigens of colorectal adenocarcinoma, the carcinoembryonic antigen （CEA） threatens human health seriously ali over the globe. Fast electrical and highly sensitive detection of the CEA with A1GaN/GaN high electron mobility transistor is demonstrated experimentally. To achieve a low detection limit, the Au-gated sensing area of the sensor is functionalized with a CEA aptamer instead of the corresponding antibody. The proposed aptasensor has successfully detected different concentrations （ranging from 50picogram/milliliter （pg/ml） to 50 nanogram/milliliter （ng/ml）） of CEA and achieved a detection limit as low as 50pg/ml at Vas = 0.5 V. The drain-source current shows a c/ear increase of 11.5μA under this bias.

关键词： CEA GaN Fast Electrical Detection of Carcinoembryonic Antigen Based on AlGaN/GaN High Electron Mobility Transistor Aptasensor

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雷击输电线路杆塔时的杆塔等效模型

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高电压技术 2011年第1期37卷 28-33页

作者：杜林糜翔杨勇杨庆重庆大学输配电装备及系统安全与新技术国家重点实验室重庆400030

为了对雷击杆塔时的波过程进行分析,研究了杆塔的等效模型。基于圆锥天线的相关理论,研究了杆塔单一支柱的等效波阻抗模型。结合实际杆塔结构,将杆塔视为4导体系统,在垂直单导体等效阻抗基础上乘以修正系数即得到实际杆塔等效阻抗。结... 详细信息

为了对雷击杆塔时的波过程进行分析,研究了杆塔的等效模型。基于圆锥天线的相关理论,研究了杆塔单一支柱的等效波阻抗模型。结合实际杆塔结构,将杆塔视为4导体系统,在垂直单导体等效阻抗基础上乘以修正系数即得到实际杆塔等效阻抗。结合波阻抗定义式,引入了4导体系统等效阻抗修正系数,其中包括电感及电容修正系数,电感修正系数由黎曼公式计算,电容修正系数由4导体系统与垂直单导体四周电场分布情况比较得到。按照得出的杆塔等效阻抗模型对500kV等级杆塔进行计算。

关键词：雷击波阻抗圆锥天线电感修正系数电容修正系数杆塔模型

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钙同位素地球化学研究新进展及其在碳酸岩-共生硅酸盐研究中的应用

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地质学报 2021年第12期95卷 3937-3960页

作者：向蜜龚迎莉刘涛田世洪东华理工大学核资源与环境国家重点实验室江西南昌330013 清华大学能源与动力工程系北京100084 中国地质科学院矿产资源研究所自然资源部成矿作用与资源评价重点实验室北京100037

作为"非传统稳定同位素"家族成员,钙同位素正受到国际地学界日益广泛的关注。钙是主要的造岩元素,也是生物必需的元素。钙在地球各圈层广泛分布,研究钙同位素的地球化学行为将有助于提高我们对各种生物过程和地质过程的认识。钙同位素... 详细信息

作为"非传统稳定同位素"家族成员,钙同位素正受到国际地学界日益广泛的关注。钙是主要的造岩元素,也是生物必需的元素。钙在地球各圈层广泛分布,研究钙同位素的地球化学行为将有助于提高我们对各种生物过程和地质过程的认识。钙同位素测定主要采用热电离质谱仪(TIMS)和多接收电感耦合等离子体质谱仪(MC-ICP-MS),分别表示为δ^(44/40)Ca和δ^(44/42)Ca。目前自然界可观测到的δ^(44/40)Ca变化范围为-2.0‰~6.75‰,约8.7‰。本文系统介绍了近年来钙同位素分析中样品溶解、化学分离、质谱测定以及高温地质过程中的钙同位素分馏及其地质应用等方面的研究成果,尤其对钙同位素在碳酸岩-共生硅酸盐岩研究中的意义、钙同位素组成以及取得的主要认识作了较为全面的介绍。阐述了放射成因^(40)Ca、部分熔融作用/分离结晶作用、地壳同化作用、古俯冲碳酸盐循环、热液蚀变作用、岩浆起源深度等对碳酸岩、硅酸盐岩的钙同位素组成造成的影响。最后,通过系统对比碳酸岩-共生硅酸盐岩的锂、镁、钙同位素研究成果,认为应该开展多元同位素体系的联合示踪。由于不同同位素体系存在相似性和差异性,而多元同位素体系相结合能有效地加强优势互补,将是同位素地球化学研究发展的一种必然趋势。

关键词：钙同位素分析方法同位素分馏联合示踪碳酸岩-共生硅酸盐岩

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Highly Sensitive Detection of Deoxyribonucleic Acid Hybridization Using Au-Gated AlInN/GaN High Electron Mobility Transistor-Based Sensors

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Chinese Physics Letters 2017年第4期34卷 75-78页

作者： xiang-mi Zhan Mei-Lan Ha Quan Wang Wei Li Hong-Ling Xiao[[ Chun Feng Li-Juan Jiang Cui-Mei Wang[[ Xiao-Liang Wang[[ Zhan-Guo Wang Key Lab of Semiconductor Materials Science Institute of Semiconductors Chinese Academy of Sciences Beijing 100083 School of microelectronics University of Chinese Academy of Sciences Beijing 100049 Beijing Key Laboratory of Low Dimensional Semiconductor Materials and Devices Beijing 100083 3 Department of Electro-mechanics Handan College Handan 05600

Gallium nitride- （GaN） based high electron mobility transistors （HEMTs） provide a good platform for biological detection. In this work, both Au-gated AlInN/GaN HEMT and AlGaN/GaN HEMT biosensors are fabricated for the detection of deoxyribonucleic acid （DNA） hybridization. The Au-gated AIInN/GaN HEMT biosensor exhibits higher sensitivity in comparison with the AlGaN/GaN HEMT biosensor. For the former, the drain-source current （VDS = 0.5 V） shows a clear decrease of 69μA upon the introduction of 1μmolL^-1 （μM） complimentary DNA to the probe DNA at the sensor area, while for the latter it is only 38 μA. This current reduction is a notable indication of the hybridization. The high sensitivity can be attributed to the thinner barrier of the AlInN/GaN heterostructure, which makes the two-dimensional electron gas channel more susceptible to a slight change of the surface charge.

关键词： GaN In Highly Sensitive Detection of Deoxyribonucleic Acid Hybridization Using Au-Gated AlInN/GaN High Electron Mobility Transistor-Based Sensors

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