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频率对半导体器件热击穿影响的理论模型

物理学报 2017年第1期66卷 334-339页

作者：张存波闫涛杨志强任伟涛朱占平西北核技术研究所高功率微波技术重点实验室西安710024

针对半导体器件中的热击穿,通过分析已有的理论模型,把频率对器件热区热产生和热传导的影响引入理论模型.利用格林函数求解热传输方程,同时对余误差函数进行近似处理,求解得到热区温度以及器件烧毁功率与频率和脉冲宽度的表达式.通过数... 详细信息

针对半导体器件中的热击穿,通过分析已有的理论模型,把频率对器件热区热产生和热传导的影响引入理论模型.利用格林函数求解热传输方程,同时对余误差函数进行近似处理,求解得到热区温度以及器件烧毁功率与频率和脉冲宽度的表达式.通过数值分析,求解得到不同频率下器件烧毁功率随脉冲宽度的变化规律以及不同脉冲宽度下器件烧毁功率随频率的变化规律,同时给出了频率对器件烧毁功率影响的物理解释.

关键词：热击穿频率脉冲宽度理论分析

Roles of liver innate immune cells in nonalcoholic fatty liver disease

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World Journal of Gastroenterology 2010年第37期16卷 4652-4660页

作者： Yu-tao zhan wei An Department of Gastroenterology and Hepatology Beijing Tongren Hospital Capital Medical University Beijing 100730 China Department of Cell Biology Capital Medical UniversityBeijing 100069China

Nonalcoholic fatty liver disease (NAFLD) has become the most common liver disease in the United States and other developed countries and is expected to increase in the next few years. Emerging data suggest that some patients with NAFLD may progress to nonalcoholic steatohepatitis (NASH), cirrhosis and even hepatocellular carcinoma. NAFLD can also promote the development and progression of disease in other organ systems, such as the cardiovascular and endocrine (i.e. diabetes) systems. Thus, understanding the pathogenesis of NAFLD is of great clinical importance and is critical for the prevention and treatment of the disease. Although the "two-hit hypothesis" is generally accepted, the exact pathogenesis of NAFLD has not been clearly established. The liver is an important innate immune organ with large numbers of innate immune cells, including Kupffer cells (KCs), natural killer T (NKT) cells and natural killer (NK) cells. Recent data show that an imbalance in liver cytokines may be implicated in the development of fatty liver disease. For example, Th1 cytokine excess may be a common pathogenic mechanism for hepatic insulin resistance and NASH. Innate immune cells in the liver play important roles in the excessive production of hepatic Th1 cytokines in NAFLD. In addition, liver innate immune cells participate in the pathogenesis of NAFLD in other ways. For example, activated KCs can generate reactive oxygen species, which induce liver injury. This review will focus primarily on the possible effect and mechanism of KCs, NKT cells and NK cells in the development of NAFLD.

关键词： Innate immune cells Nonalcoholic fatty liver disease Kupffer cell Natural killer T cell Natural killer cell

Revolutionizing breast cancer detection:Advances in fluorescent probe technology

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Nano Research 2025年第1期18卷 653-674页

作者： Qian Gao Lin Tang Jun zhan Yiyuan Xue Feng Luo State Key Laboratory of Oral Diseases&National Center for Stomatology&National Clinical Research Center for Oral Diseases West China Hospital of StomatologySichuan UniversityChengdu 610041China Emergency Obstetrics and Gynecology West China Second University HospitalSichuan UniversityChengdu 610041China Department of Obstetrics and Gynecology West China Second University HospitalSichuan UniversityChengdu 610041China Department of Prosthodontics West China School of StomatologySichuan UniversityChengdu 610041China

With the increasing incidence of breast cancer globally,there is an urgent demand for enhanced diagnostic and therapeutic *** comprehensive review explores advancements in fluorescent probe technology for breast cancer imaging and early *** probes offer unparalleled sensitivity and specificity in detecting cancer biomarkers,enabling early diagnosis and delineation of tumor margins during *** categorize these probes into molecular,nano,ratiometric,the second near-infrared window(NIR-II),and multifunctional varieties,each with unique capabilities for targeting specific cancer *** review highlights recent innovations in probe design,emphasizing their applications in pathogenesis studies,drug development,precision medicine,and fluorescence-guided *** their promising clinical potential,challenges such as safety,biomarker targeting accuracy,system compatibility,and clinical translation *** these hurdles is crucial for the integration of fluorescent probes into standard cancer care,aiming to improve treatment outcomes and patient quality of life.

关键词： breast cancer fluorescent probes imaging early diagnosis biomarker

Glycosyltransferases and non-alcoholic fatty liver disease

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World Journal of Gastroenterology 2016年第8期22卷 2483-2493页

作者： Yu-tao zhan Hai-Ying Su wei An Department of Gastroenterology Beijing Tongren Hospital Capital Medical University Department of Obstetrics and Gynecology Shandong Jining First People’s Hospital Department of Cell Biology Municipal Laboratory for Liver Protection and Regulation of Regeneration Capital Medical University

Non-alcoholic fatty liver disease(NAFLD) is the most common form of chronic liver disease and its incidence is increasing worldwide. However, the underlying mechanisms leading to the development of NAFLD are still not fully understood. Glycosyltransferases(GTs) are a diverse class of enzymes involved in catalyzing the transfer of one or multiple sugar residues to a wide range of acceptor molecules. GTs mediate a wide range of functions from structure and storage to signaling, and play a key role in many fundamental biological processes. Therefore, it is anticipated that GTs have a role in the pathogenesis of NAFLD. In this article, we present an overview of the basic information on NAFLD, particularly GTs and glycosylation modification of certain molecules and their association with NAFLD pathogenesis. In addition, the effects and mechanisms of some GTs in the development of NAFLD are summarized.

关键词： Non-alcoholic fatty liver disease Pathogenesis Glycosyltransferases Glycosylation

Farmers using insurance and cooperatives to manage agricultural risks: A case study of the swine industry in China

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Journal of Integrative Agriculture 2019年第12期18卷 2910-2918页

作者： zhanG Yan-yuan JU Guang-wei zhan Jin-tao College of Economics and Management Nanjing Forestry UniversityNanjing 210037P.R.China Chinese Academy of Agricultural Sciences Beijing 100081P.R.China College of Economics and Management Nanjing Agricultural UniversityNanjing 210095P.R.China

Purchasing agricultural insurance and joining agricultural cooperatives are two prevalent instruments used by farmers in China for dealing with agricultural risks. Data from 443 swine farmers in Jiangsu and Henan provinces of China were collected. Factors affecting the farmers’ decision to purchase agricultural insurance and join agricultural cooperatives were assessed. The possibility of simultaneous use of both instruments and the potential correlation between these two decisions was considered as well. Results showed that the farmers’ decision to use agricultural insurance and cooperatives was positively correlated, indicating that farmers who purchased agricultural insurance which mainly used to mitigate production risks were more likely to join agricultural cooperatives which more used to share market risks, and vice versa. Farmers’ knowledge of swine insurance and trust in the local government positively impacted the purchase of agricultural insurance, while education, years involved in swine production and scale of swine production positively impacted farmers joining agricultural cooperatives.

关键词： agricultural insurance agricultural cooperatives simultaneous decisions Bivariate Probit China

低饱和磁化强度旋磁In-BiCaVIG单晶小球制备

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磁性材料及器件 2020年第6期51卷 53-57页

作者：魏占涛游斌姜帆陈运茂何志强西南应用磁学研究所四川绵阳621000

采用助熔剂法以Bi2O3、PbO为助溶剂结合加速坩埚转动技术生长了4πMs为400 G、250 G、200 G的三种石榴石型In-BiCaVIG单晶,不同配方的单晶材料均能生长出线度在10 mm以上且包杂极少的单晶颗粒。采用“V”型槽研磨技术对系列单晶小球进... 详细信息

采用助熔剂法以Bi2O3、PbO为助溶剂结合加速坩埚转动技术生长了4πMs为400 G、250 G、200 G的三种石榴石型In-BiCaVIG单晶,不同配方的单晶材料均能生长出线度在10 mm以上且包杂极少的单晶颗粒。采用“V”型槽研磨技术对系列单晶小球进行了磨抛加工处理,三种型号小球的球形度在1.0041~1.0048之间,略优于同尺寸的进口小球(球形度为1.0056)。对制备的三种小球进行了器件试用,结果表明,三种型号的单晶小球性能良好,能够满足相应滤波器的应用要求。XD4C型单晶小球的批量合格率接近84%,且批量性能一致性与进口小球相近;而XD2.5C和XD2C两种型号单晶小球的合格率则不到76%,还有待进一步提高。

关键词： In-BiCaVIG 旋磁铁氧体饱和磁化强度单晶小球

Oxide coating mechanism during fluidized bed reduction: solid-state reaction characteristics between iron ore particles and MgO

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International Journal of Minerals,Metallurgy and Materials 2016年第9期23卷 1019-1028页

作者： Lei Guo Jin-tao Gao Yi-wei Zhong Han Gao zhan-cheng Guo State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing

Experiments on the solid-state reaction between iron ore particles and MgO were performed to investigate the coating mechanism of MgO on the iron ore particles＇ surface during fluidized bed reduction. MgO powders and iron ore particles were mixed and compressed into briquettes and, subsequently, roasted at different temperatures and for different time periods. A Mg-containing layer was observed on the outer edge of the iron ore particles when the roasting temperature was greater than 1173 K. The concentration of Fe in the Mg-containing layer was evenly distributed and was approximately 10wt%, regardless of the temperature change. Boundary layers of Mg and Fe were observed outside of the iron ore particles. The change in concentration of Fe in the boundary layers was simulated using a gas–solid diffusion model, and the diffusion coefficients of Fe and Mg in these layers at different temperatures were calculated. The diffusion activation energies of Fe and Mg in the boundary layers in these experiments were evaluated to be approximately 176 and 172 k J/mol, respectively.

关键词： fluidized beds coating solid reaction ferric oxide magnesia diffusion coefficient

Removal of phosphorus-rich phase from high-phosphorous iron ore by melt separation at 1573 K in a super-gravity field

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International Journal of Minerals,Metallurgy and Materials 2016年第7期23卷 743-750页

作者： Jin-tao Gao Lei Guo Yi-wei Zhong Hong-ru Ren zhan-cheng Guo State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing

A new approach of removing the phosphorus-rich phase from high-phosphorous iron ore by melt separation at 1573 K in a super-gravity field was investigated. The iron？slag separation by super-gravity resulted in phosphorus being effectively removed from the iron-rich phase and concentrated as a phosphorus-rich phase at a temperature below the melting point of iron. The samples obtained by super-gravity exhibited obvious layered structures. All the iron grains concentrated at the bottom of the sample along the super-gravity direction, whereas the molten slag concentrated in the upper part of the sample along the opposite direction. Meanwhile, fine apatite crystals collided and grew into larger crystals and concentrated at the slag–iron interface. Consequently, in the case of centrifugation with a gravity coefficient of G = 900, the mass fractions of the slag phase and iron-rich phase were similar to their respective theoretical values. The mass fraction of MFe in the iron-rich phase was as high as 97.77wt% and that of P was decreased to 0.092wt%.

关键词： ironmaking super-gravity melt separation dephosphoration

Kinematics-based four-state trajectory tracking control of a spherical mobile robot driven by a 2-DOF pendulum

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Chinese Journal of Aeronautics 2019年第6期32卷 1530-1540页

作者： wei LI Qiang zhan Robotics Institute Beihang UniversityBeijing 100083China Ecole Centrale de Pékin Beihang UniversityBeijing 100083China

Spherical mobile robot has compact structure, remarkable stability, and flexible motion,which make it have many advantages over traditional mobile robots when applied in those unmanned environments, such as outer planets. However, spherical mobile robot is a special highly under-actuated nonholonomic system, which cannot be transformed to the classic chained form. At present, there has not been a kinematics-based trajectory tracking controller which could track both the position states and the attitude states of a spherical mobile robot. In this paper, the four-state(two position states and two attitude states) trajectory tracking control of a type of spherical mobile robot driven by a 2-DOF pendulum was studied. A controller based on the shunting model of neurodynamics and the kinematic model was deduced, and its stability was demonstrated with Lyapunov’s direct method. The control priorities of the four states were allocated according to the magnification of each state tracking error in order to firstly ensure the correct tracking of the position states. The outputs(motor speeds) of the controller were regulated according to the maximum speeds and the maximum accelerations of the actuation motors in order to solve the speed jump problem caused by initial state errors, and continuous and bounded outputs were obtained. The effectiveness including the anti-interference ability of the proposed trajectory tracking controller was verified through MATLAB simulations.

关键词： Kinematics Lyapunov methods Neurodynamics Nonholonomic systems Spherical mobile robot Trajectory tracking