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Effects of Strain Channel on Electron Irradiation Tolerance of InP-based HEMT Structures

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原子能科学技术 2023年第12期57卷 2288-2294页

作者： FANG Renfeng CAO Wenyu WEI Yanfeng WANG Yin chen Chuanliang YAN Jiasheng XING Yan liang Guijie ZHOU Shuxing Hubei Key Laboratory of Low Dimensional Optoelectronic Materials and Devices Hubei University of Arts and ScienceXiangyang 441053China Hubei Key Laboratory of High Power Semiconductor Technology Hubei TECH Semiconductor Co.LtdXiangyang 441021China Hubei Longzhong Laboratory Xiangyang 441000China

The introduction of strain In_(x)Ga_(1-x)As channel with high In content increases the confinement of the two-dimensional electron gas(2DEG)and further improves the high-frequency performance of InGaAs/InAlAs/InP *** effect of In_(x)Ga_(1-x)As channel with different In contents on electron irradiation tolerance of InP-based HEMT structures in terms of 2DEG mobility and density has been *** experiment results show that,after the same high electron irradiation dose,the 2DEG mobility and density in InP-based HEMT structures with strain In_(x)Ga_(1-x)As(x>0.53)channel decrease more dramatically than that without strain In_(0.53)Ga_(0.47)As ***,the degradation of 2DEG mobility and density becomes more severe as the increase of In content and strain in the In_(x)Ga_(1-x)As *** research results can provide some suggestions for the design of radiation-resistant InP-based HEMTs.

关键词： InP-based HEMT strain channel two-dimensional electron gas electron irradiation

In vivo retention of poloxamer-based in situhydrogels for vaginal application in mouse and rat models

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Acta Pharmaceutica Sinica B 2017年第4期7卷 502-509页

作者： Yu Liu Fujin Yang Linglin feng Long Yang Lingyun chen Gang Wei Weiyue Lu Key Laboratory of Smart Drug Delivery Ministry of EducationFudan UniversityShanghai 201203China Department of Pharmaceutics School of PharmacyFudan UniversityShanghai 201203China Yunnan University of Traditional Chinese Medicine Kunming 650500China Shanghai Institute of Planned Parenthood Research National Population and Family Planning Key Laboratory of Contraceptives Drugs and DevicesShanghai 200032China

The purpose of this study is to evaluate the in vivo retention capabilities of poloxamer-based in situ hydrogels for vaginal application with nonoxinol-9 as the model drug. Two in situ hydrogel formulations, which contained 18% poloxamer 407 plus 1% poloxamer 188 (GEL1, relative hydrophobic) or 6% poloxamer 188 (GEL2, relative hydrophilic), were compared with respect to the rheological properties, in vitro hydrogel erosion and drug release. The vaginal retention capabilities of these hydrogel formulations were further determined in two small animal models, including drug quantitation of vaginal rinsing fluid in mice and isotope tracing with 99mTc in rats. The two formulations exhibited similar phase transition temperatures ranging from 27 to 32 °C. Increasing the content of poloxamer 188 resulted in higher rheological moduli under body temperature, but slightly accelerated hydrogel erosion and drug release. When compared in vivo, GEL1 was eliminated significantly slower in rat vagina than GEL2, while the vaginal retention of these two hydrogel formulations behaved similarly in mice. In conclusion, increases in the hydrophilic content of formulations led to faster hydrogel erosion, drug release and intravaginal elimination. Rats appear to be a better animal model than mice to evaluate the in situ hydrogel for vaginal application.

关键词： Vaginal administration Poloxamer Thermosensitive hydrogel Retention Nonoxinol-9

A new isotropic negative thermal expansion material of CaSnF_(6)with facile and low-cost synthesis

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Nano Research 2023年第4期16卷 5964-5972页

作者： Qilong Gao Sen Zhang Yixin Jiao Yongqiang Qiao Andrea Sanson Qiang Sun Xinwei Shi Erjun liang Jun chen Key Laboratory of Materials Physics of Ministry of Education and School of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450052China Department of Physics and Astronomy University of PadovaPadova I-35131Italy Beijing Advanced Innovation Center for Materials Genome Engineering Department of Physical ChemistryUniversity of Science and Technology BeijingBeijing 100083China

Double ReO_(3)-type fluorides have a great interest in the field of negative thermal expansion(NTE)and luminescent ***,their application is limited by the scarcity of quantity,expensive raw materials,and harsh preparation *** this work we have found a new NTE material,CaSnF_(6),by applying the concept of the average atomic *** importantly,different from the previous solid-phase sintering and direct fluorination methods,the nano CaSnF6 has been synthesized for the first time by solvothermal *** results of X-ray diffraction(XRD)and Raman spectroscopy show that a phase transition occurs from rhombohedral(R3)to cubic(Fm3m)structure at about 200 K,and a strong isotropic NTE(αv=−15.78×10^(−6)K^(−1))appears in the cubic *** dynamics calculations from first-principles illustrate that the NTE is due to the transverse vibration of fluorine atoms excited by low-frequency *** work not only broadens the NTE family of fluorides,but also provides a new facile and low-cost fabricati on method for the preparation of NTE fluorides.

关键词： negative thermal expansion double ReO_(3)-type fluorides Grüneisen parameters lattice dynamics

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基于叠加原理的隧道爆破近区振动规律研究

振动与冲击 2018年第2期37卷 182-188页

作者：谢烽韩亮刘殿书李晨中国矿业大学力学与建筑工程学院北京100083

为了改善隧道近区振动强度预测的准确性,以线性叠加理论的假设条件为基础,建立了符合现场实际的隧道近区振速计算模型。以北京兴延高速公道浇花峪右线隧道,里程为YK28+190到YK28+354范围内实测数据验证模型的可行性,并对隧道近区振动规... 详细信息

为了改善隧道近区振动强度预测的准确性,以线性叠加理论的假设条件为基础,建立了符合现场实际的隧道近区振速计算模型。以北京兴延高速公道浇花峪右线隧道,里程为YK28+190到YK28+354范围内实测数据验证模型的可行性,并对隧道近区振动规律进行研究。研究表明:(1)基于波形叠加的爆破振动预测模型适用于隧道近区振动预测;(2)随着单孔装药量的增加,平行于掌子面的隧道截面上能量密度增加,振速等值线的强度增大,轮廓形态出现变化,中心测线振速的增长幅度大于两边,在爆破近区这种现象尤为明显;隧道已开挖区垂直掌子面的测线方向上,随着离爆源的距离增加,振速的衰减速度逐渐变小。(3)随掏槽孔孔数目的增多,相同数值的等值线外移,且等值线逐渐平缓;平行于掌子面的隧道截面上,振速的增加幅度逐渐减小。

关键词：爆炸力学波形叠加隧道爆破近区振动预测

Gluconeogenesis during starvation and refeeding phase is affected by previous dietary carbohydrates levels and a glucose stimuli during early life in Siberian sturgeon(Acipenser baerii)

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Animal Nutrition 2017年第3期3卷 284-294页

作者： Xiaofang liang Jia Wang Guan Gong Min Xue Yingchao Dong Xiufeng Wu Xin Wang Chunshan chen Xufang liang Yuchang Qin National Aquafeed Safety Assessment Station Feed Research Institute Chinese Academy of Agricultural Sciences Key Laboratory of Feed Biotechnology of Ministry of Agriculture Feed Research Institute Chinese Academy of Agricultural Sciences Beijing Aquatic Wildlife Rescue and Conservation Center College of Fisheries Huazhong Agricultural University Institute of Animal Science Chinese Academy of Agricultural Sciences

Gluconeogenesis responses was assessed during a short starvation period and subsequent refeeding in Siberian sturgeon(Acipenser baerii) previously fed different dietary carbohydrates levels and experienced to a glucose stimuli during early life. The sturgeon larvae were previously fed either a high glucose diet(G) or a low glucose diet(F) from the first feeding to yolk absorption(8 to 12 d post-hatching [dph]). Each group of fish was sub-divided into 2 treatments at 13 dph and was fed either a high-carbohydrate diet(H) or a low carbohydrate diet(L) until 20 wk. In the current study, the fish in 4 groups(GL, FL, GH and FH) were experienced to starvation for 21 d following by re-feeding of their corresponding diets for 21 *** were sampled at postprandial 6 and 24 h before starvation(P6 h and P24 h), starvation 7,14 and 21 d(S7, S14 and S21) and 1, 7,14 and 21 d during refeeding(R1, R7, R14 and R21). Plasma samples during refeeding were taken at P6 h at each time point. Glycaemia levels, liver and muscle glycogen contents,activities and mRNA levels of hepatic gluconeogenic enzymes were examined. We found that both dietary carbohydrate levels and early glucose stimuli significantly affected the metabolic responses to starvation and refeeding in Siberian sturgeon(P < 0.05). During prolonged starvation, Siberian sturgeon firstly mobilized the liver glycogen and then improved gluconeogenesis when the dietary carbohydrates were abundant, whereas preserved the liver glycogen stores at a stable level and more effectively promoted gluconeogenesis when the dietary carbohydrates are absent to maintain glucose *** refeeding, as most teleostean, Siberian sturgeon failed controlling the activities and mRNA levels of phosphoenolpyruvate carboxykinase cytosolic forms(PEPCK-C), fructose-1,6-bisphosphatase(FBPase),but particularly controlled phosphoenolpyruvate carboxykinase mitochondrial forms(PEPCK-M) activities and mRNA expression of glucose-6-phosphatase(G6 Pase,

关键词： Early nutritional programming Fasting Refeeding Gluconeogenesis Acipenser baeri

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磁流变半主动悬架动力学特性的试验研究

汽车工程 2013年第1期35卷 72-77页

作者：冯占宗陈思忠梁义北京理工大学机械与车辆学院北京100081 一汽东机工减振器有限公司长春130025

通过台架试验为自制磁流变减振器建立可控阻尼力-励磁模型以便于计算机控制,并根据1/4车辆半主动悬架动力学模型确定天棚阻尼开关控制算法和LQR最优控制算法的相关参数;应用Labview模块化语言开发了数据采集与预处理、控制算法和计算机... 详细信息

通过台架试验为自制磁流变减振器建立可控阻尼力-励磁模型以便于计算机控制,并根据1/4车辆半主动悬架动力学模型确定天棚阻尼开关控制算法和LQR最优控制算法的相关参数;应用Labview模块化语言开发了数据采集与预处理、控制算法和计算机与PWM通信控制等模块,并在1/4车辆悬架试验台上进行半主动振动控制与无控制的对比试验。结果表明,自制的磁流变减振器结合所开发的控制算法能有效抑制车辆振动。

关键词：磁流变减振器半主动悬架动力学特性试验研究

A proof of concept for neutralizing antibody-guided vaccine design against SARS-CoV-2

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National Science Review 2021年第8期8卷 147-157页

作者： Li Zhang Lei Cao Xing-Su Gao Bin-Yang Zheng Yong-Qiang Deng Jing-Xin Li Rui feng Qian Bian Xi-Ling Guo Nan Wang Hong-Ying Qiu Lei Wang Zhen Cui Qing Ye Geng chen Kui-Kui Lu Yin chen Yu-Tao chen Hong-Xing Pan Jiaping Yu Wenrong Yao Bao-Li Zhu Jianping chen Yong Liu cheng-feng Qin Xiangxi Wang feng-Cai Zhu National Health Commission of the People’s Republic of China Key Laboratory of Enteric Pathogenic Microbiology (Jiangsu Provincial Center for Disease Control and Prevention) Center for Global Health School of Public HealthNanjing Medical University CAS Key Laboratory of Infection and Immunity National Laboratory of MacromoleculesInstitute of BiophysicsChinese Academy of Sciences Guangzhou Regenerative Medicine and Health Guangdong Laboratory Jiangsu Rec-biotechnology Co.Ltd State Key Laboratory of Pathogen and Biosecurity Beijing Institute of Microbiology and Epidemiology

Mutations and transient conformational movements of the receptor binding domain(RBD) that make neutralizing epitopes momentarily unavailable present immune escape routes for severe acute respiratory syndrome coronavirus 2(SARS-CoV-2). To mitigate viral escape, we developed a cocktail of neutralizing antibodies(NAbs) targeting epitopes located on different domains of spike(S) protein. Screening of a library of monoclonal antibodies generated from peripheral blood mononuclear cells of COVID-19 convalescent patients yielded potent NAbs, targeting the N-terminal domain(NTD) and RBD domain of S, effective at n M concentrations. Remarkably, a combination of RBD-targeting NAbs and NTD-binding NAbs, FC05, enhanced the neutralization potency in cell-based assays and an animal model. Results of competitive surface plasmon resonance assays and cryo-electron microscopy(cryo-EM) structures of antigen-binding fragments bound to S unveil determinants of immunogenicity. Combinations of immunogens, identified in the NTD and RBD of S, when immunized in rabbits and macaques, elicited potent protective immune responses against SARS-CoV-2. More importantly, two immunizations of this combination of NTD and RBD immunogens provided complete protection in macaques against a SARS-CoV-2 challenge, without observable antibody-dependent enhancement of infection. These results provide a proof of concept for neutralization-based immunogen design targeting SARS-CoV-2 NTD and RBD.

关键词： SARS-CoV-2 neutralizing antibodies vaccine development structure-based immunogen design

Research on bubble trajectory and flow structure in helical-axial multiphase pump

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Journal of Hydrodynamics 2023年第3期35卷 533-548页

作者： Hui Quan chen-xi Sun Kai Song Ya-nan Li Xiao-yi Liu Xue-ling Yang liang Wang College of Energy and Power Engineering Lanzhou University of TechnologyLanzhou 730050China College of Engineering Nihon UniversityKoriyamaFukushimaJapan Shenyang Shengtai Environmental Protection Technology Co.Ltd Shenyang 110122China

The oil-gas two-phase hybrid transportation technology is one of the innovative technology directions for the exploitation and transportation of marginal and deep ocean *** helical-axial multiphase pump is a key equipment for oil and gas *** this stage,most of the research on this kind of pump focuses on the improvement of the structure and conveying ***,because of insufficient understanding of the flow behavior and mechanism of bubbles,it is easy to cause the gas-liquid *** this paper,the numerical simulation and test are combined to explore the changes in the bubble trajectory and flow structure of the helical-axial multiphase *** results shown that when the speed is lower than 1200 r/min,the bubble reaches the maximum volume at 1/2 of the midline of the impeller blade and it contact with the pressure surface,broken to the suction *** the rotation speed is higher than 1450 r/min,the number of bubbles in the impeller increases and the size *** backflow occurs in the tip clearance and strength increases *** research results have important significance for the theoretical design and engineering application of the helical-axial multiphase pump.

关键词： Helical-axial multiphase pump gas-liquid two-phase flow visualization experiment bubble trajectory flow structure

Left armpit subcutaneous metastasis of gastric cancer: A case report

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World Journal of Clinical Cases 2019年第23期7卷 4137-4143页

作者： feng-Jun He Peng Zhang Mo-Jin Wang Yi chen Wen Zhuang Department of Gastrointestinal Surgery West China Hospital Sichuan University

BACKGROUND Gastric cancer is the third most lethal malignant tumor *** has always been a major cause of poor *** evidence shows that the most common sites for metastasis of gastric carcinoma are the liver(48%),peritoneum(32%),lung(15%),and bone(12%);however,subcutaneous metastasis is are and occurs in approximately 0.8%of *** report a rare case of armpit subcutaneous metastasis of gastric *** best surgical window was missed,as a result of lacking attention of the *** SUMMARY A 69-year-old man who had previously undergone radical gastrectomy and received eight cycles of oral chemotherapy for gastric cancer showed a rapidly growing mass in his the left armpit;within just 3 mo,the mass grew to a size of 6.9 cm×4.4 cm×5.7 *** Doppler ultrasonography and Positron emission tomography/computed tomography prompted the possibility of metastasis of the *** needle aspiration biopsy guided by color Doppler ultrasound showed the presence of cancer cells in the *** examination showed CDX-2(+),PCK(+),CK20(+),CK7(-),and TTF(-),which supported the metastasis of gastric *** the risk of resection,the patient did not undergo surgical *** The case indicates that unidentified subcutaneous masses in patients with a history of gastric cancer should be carefully evaluated.

关键词： Stomach neoplasms Neoplasm metastasis Subcutaneous Case report Cancer therapy Skin neoplasms