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Thermal and Mechanical Properties of Graphene-Titanium Composites Synthesized by Microwave Sintering

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Acta Metallurgica Sinica(English Letters) 2016年第8期29卷 707-713页

作者： Wen-Zhi Yang Wei-ming Huang Zhi-Feng Wang Fu-Jun Shang Wei Huang Bao-yu Zhang Ningbo Branch of China Academy of Ordnance Science College of Mechanical Engineering and Mechanics Ningbo University

The x wt%graphene-Ti composites（x = 0,0.2,0.3 and 0.4） were obtained using the powder metallurgy *** X-ray diffraction results demonstrated that the peak intensity of graphene increased monotonically with increasing graphene ***,the number of grain boundary and interface between graphene and matrix increased as graphene increased,which led to a sharp rise of thermal *** thermal conductivity and specific heat capacity of composites initially decreased drastically with addition of graphene,but then increased with increasing graphene content from 0.2 to 0.4 wt%.This phenomenon was connected with the graphene content and the characteristics of Ti matrix（pores,grain boundary and interface between graphene and matrix）.The variation of the compressive strength of composites was attributed to the interaction effects of the average grain size of the Ti matrix（d_m） and the volume fraction（V_f） and aspect ratio（A） of graphene.

关键词： Graphene Metal-matrix composites Thermal properties Compressive strength

Natural variation and evolutionary dynamics of transposable elements in Brassica oleracea based on next-generation sequencing data

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Horticulture Research 2020年第1期7卷 990-1001页

作者： Zhen Liu Miao Fan Er-Kui yue yu Li Ruo-Fu Tao Hai-ming Xu ming-Hua Duan Jian-Hong Xu Institute of Crop Science Zhejiang Key Laboratory of Crop GermplasmZhejiang University310058 HangzhouPeople’s Republic of China Zhejiang Zhengjingyuan Pharmacy Chain Co. Ltd.&Hangzhou Zhengcaiyuan Pharmaceutical Co.Ltd.310021 HangzhouPeople’s Republic of China

Brassica oleracea comprises various economically important vegetables and presents extremely diverse morphological *** provide a rich source of nutrition for human health and have been used as a model system for studying *** elements(TEs)account for nearly 40%of the *** genome and contribute greatly to genetic diversity and genome *** the proliferation of TEs has led to a large expansion of the *** genome,little is known about the population dynamics and evolutionary activity of TEs.A comprehensive mobilome profile of 45,737 TE loci was obtained from resequencing data from 121 diverse accessions across nine *** *** 70%(32,195)of the loci showed insertion polymorphisms between or within *** particular,up to 1221 loci were differentially fixed among *** analysis revealed that the distribution of the population frequency of TE loci was highly variable across different TE superfamilies and families,implying a diverse expansion history during host genome *** findings provide better insight into the evolutionary dynamics and genetic diversity of *** genomes and will potentially serve as a valuable resource for molecular markers and association studies between TE-based genomic variations and morphotype-specific phenotypic differentiation.

关键词： evolutionary dynamics elements

维普期刊数据库评论

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维普期刊数据库

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激光技术在天基成像中的应用进展

航天器工程 2024年第4期33卷 108-116页

作者：张靖鹏胡海鹰董磊郑珍珍陈起行夏明颜九妹喻珮珮中国科学院微小卫星创新研究院上海201304 上海微小卫星工程中心上海201304

针对高轨目标的精细特征识别、亚厘米级空间碎片的探测、全天时全天域成像的主动成像等需求,对目前3类采用激光技术的天基成像手段包括激光雷达三维成像技术、逆合成孔径激光雷达(ISAL)成像技术、激光主动照明成像技术的工作原理、成像... 详细信息

针对高轨目标的精细特征识别、亚厘米级空间碎片的探测、全天时全天域成像的主动成像等需求,对目前3类采用激光技术的天基成像手段包括激光雷达三维成像技术、逆合成孔径激光雷达(ISAL)成像技术、激光主动照明成像技术的工作原理、成像性能、优势、应用发展现状进行了对比和总结归纳。对于几类天基激光成像手段,其关键技术均包括了发展小型化高功率激光器,以增强成像的信噪比和成像距离,此外,对于三维激光成像和ISAL成像技术,需要发展大面阵探测器的技术,来提高其成像的视场。总结目前的各类成像手段,ISAL是目前对天基远距离目标逆光成像的唯一手段,具有极大的发展潜力,但在应用时需要考虑逆光条件下的目标跟踪捕获,未来天基应用可以考虑采用逆合成孔径微波雷达技术(ISAR)进行视场引导跟踪。

关键词：激光技术天基态势感知精细特征识别空间碎片

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Origin of low coercivity of high La-Ce-containing Nd-Fe-B sintered magnets

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Rare Metals 2021年第1期40卷 180-184页

作者： Zhi Li yu-Qing Li Wei-Qiang Liu Dan Wu Hao Chen Wei-Xing Xia ming yue College of Materials Science and Engineering Key Laboratory of Advanced Functional MaterialsMinistry of Education of ChinaBeijing University of TechnologyBeijing 100124China Key Laboratory of Magnetic Materials and Devices Ningbo Institute of Material Technology and EngineeringChinese Academy of SciencesNingbo 315201China

The origin of low coercivity of high La-Cecontaining Nd-Fe-B sintered magnets was analyzed based on characterization of the microstructure,magnetic domain structure,and magnetization reversal *** can be found that the coercivity of magnet decreases sharply and the ratio value of coercivity(H_(cj))to anisotropic field(H_(A))is below the theoretical value when the amount of La-Ce substitution for Nd is more than 40 wt%.The grain boundaries with poor magnetic isolation in the high La-Cecontaining Nd-Fe-B sintered magnets play an important role in reducing the coercivity of the *** addition,a larger proportion of the reversible portions can be found for the magnet with a large content of La-Ce,which will lead to the low performance of the magnet.

关键词： La-Ce-containing Nd-Fe-B sintered magnets Magnetic properties Magnetic domain Magnetization reversal

面向监视侦查的光电探测场景仿真系统总体设计

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激光与红外 2019年第9期49卷 1100-1107页

作者：于鲲丛明煜哈尔滨工业大学航天学院空间光学工程研究中心

现有仿真设计软件功能还难以满足空天地一体化光电探测系统总体设计的需求,迫切需要开发一套光电探测场景仿真设计软件。通过对光电探测场景组成要素、探测链路与任务模式的分析,规划了仿真系统结构、功能与关键技术,设计了面向对象的... 详细信息

现有仿真设计软件功能还难以满足空天地一体化光电探测系统总体设计的需求,迫切需要开发一套光电探测场景仿真设计软件。通过对光电探测场景组成要素、探测链路与任务模式的分析,规划了仿真系统结构、功能与关键技术,设计了面向对象的数据结构属性方法与仿真计算流程,在VS2010+QT5.4环境下开发了光电探测场景仿真系统的基础版本。给出了美国STSS天基红外监视系统中段目标探测任务仿真实例计算结果和笔者团队的光电探测仿真技术主要应用成果。

关键词：计算机仿真光电探测监视侦查总体设计成像仿真面向对象

Effect of Nb on the dynamic recrystallization behavior of high-grade pipeline steels

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International Journal of Minerals,Metallurgy and Materials 2010年第6期17卷 742-747页

作者： Tao Niu Yong-lin Kang Hong-wei Gu yu-qun Yin ming-liang Qiao Jin-xing Jiang School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing 10083 China Nanjing Iron and Steel Co. Ltd. Nanjing 210035 China

The dynamic recrystallization （DRX） behavior of high-grade X80/X100 pipeline steels with different Nb contents was investi- gated through single pass compression experiment using a Gleeble 1500 thermomechanical simulator. By the regression of stress-sWain data obtained in the experiment, the deformation activation energy of DRX was identified, and the critical strain was calculated with the Po- liak-Jonas （P-J） method. Based on the analysis, the occurrence condition and kinetics of DRX were determined. The results show that as the Nb content increases from 0.08wt% to 0.095wt%, the activation energy of recrystallization raises from 365 to 395 kJ/mol. The critical swain of DRX can be determined more accurately by the P-J method, and the ratios of critical swain to peak sWain of XS0 and X100 pipeline steels are 0.51 and 0.49, respectively, which are similar to the results achieved by other researchers and calculated with empirical formulae.

关键词： pipeline steels niobium dynamic recrystallization activation energy retardation kinetics

解毒化瘀颗粒调控ROS-NLRP3信号通路缓解肝衰竭大鼠肝脏炎症应激的实验研究

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时珍国医国药 2024年第5期35卷 1025-1029页

作者：吴智鹏张荣臻王明刚张钰琴王秀峰广西中医药大学研究生院广西南宁530200 广西中医药大学第一附属医院广西南宁530023 广西医科大学基础医学院细胞生物学与遗传学教研室广西南宁530021

目的分析解毒化瘀颗粒(JDHY)通过调控ROS-NLRP3信号通路改善肝衰竭大鼠肝脏炎症反应的相关分子机制。方法将36只雄性Wistar大鼠随机分为空白组(Control)、模型组(Model)、解毒化瘀颗粒组(JDHY),每组各12只。采用D-氨基半乳糖(D-GalN)联... 详细信息

目的分析解毒化瘀颗粒(JDHY)通过调控ROS-NLRP3信号通路改善肝衰竭大鼠肝脏炎症反应的相关分子机制。方法将36只雄性Wistar大鼠随机分为空白组(Control)、模型组(Model)、解毒化瘀颗粒组(JDHY),每组各12只。采用D-氨基半乳糖(D-GalN)联合脂多糖(LPS)一次性腹腔注射建立急性肝衰竭大鼠模型。JDHY组在造模前给予JDHY(57.55 g·kg^(-1)·d^(-1)),连续灌胃72h并延续至造模后24h。造模后24h处死各组大鼠,收集血清及组织样本,采用全自动生化分析仪测定血清ALT、AST和TBIL水平,ELISA测定血清IL-1β和IL-18,评估ROS生成,免疫组织化学分析肝组织NLRP3和GSDMD表达,蛋白质印迹分析肝组织NLRP3、GSDMD、GSDMD-N、ASC和Caspase-1表达。结果JDHY能有效改善肝衰竭大鼠肝功能(ALT、AST、TBIL)(P<0.05),减少ROS过度产生(P<0.05)和炎症因子(IL-1β、IL-18)释放。此外,与模型组比较,JDHY降低了肝衰竭大鼠肝组织中NLRP3、GSDMD、GSDMD-N、ASC和Caspase-1的表达(P<0.05)。结论JDHY能抑制ROS-NLRP3信号通路过度激活、减少促炎因子释放,缓解肝脏炎症应激水平从而拮抗肝衰竭。

关键词：解毒化瘀颗粒 ROS-NLRP3炎症小体信号通路肝衰竭

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1例人偏肺病毒感染中年女性的临床分析

中国实用医药 2024年第8期19卷 156-160页

作者：于明霞林蕊艳祝兆萌北京市通州区梨园社区卫生服务中心 101100 首都医科大学附属北京潞河医院呼吸与危重症医学科 101149

患者女性,48岁,2023年6月13日主因新型冠状病毒肺炎住院,核酸转阴后,于6月19日出院。6月22日再次出现发热,体温最高38.1℃,伴畏寒,肌肉酸痛,胸部CT提示双肺多发斑片状磨玻璃影、实变影,部分较前吸收,部分较前新发,于6月25日再次入本科... 详细信息

患者女性,48岁,2023年6月13日主因新型冠状病毒肺炎住院,核酸转阴后,于6月19日出院。6月22日再次出现发热,体温最高38.1℃,伴畏寒,肌肉酸痛,胸部CT提示双肺多发斑片状磨玻璃影、实变影,部分较前吸收,部分较前新发,于6月25日再次入本科住院治疗。体格检查可闻及湿啰音及散在哮鸣音。血气分析(不吸氧):酸碱度(pH)7.41,动脉血二氧化碳分压(PaCO_(2))36 mm Hg(1 mm Hg=0.133 kPa),动脉血氧分压(PaO_(2))57 mm Hg,氧合指数(P/F ratio)282 mm Hg;血常规:白细胞计数(WBC)5.85×10^(9)/L,中性粒细胞百分比(NEU%)68%,淋巴细胞百分数(LYM)26%,血红蛋白(Hb)116 g/L;考虑社区获得性肺炎(CAP)。完善检查,呼吸道病毒十三项提示偏肺病毒核酸阳性,支气管镜灌洗液微生物二代基因测序(NGS)提示偏肺病毒序列数24469条。综合分析诊断为肺炎-人偏肺病毒(hMPV)感染。停用抗生素,予以对症治疗及中药治疗。复查胸部CT提示两肺散在斑片影明显吸收。说明随着宏基因组学的应用普及,越来越多社区获得性肺炎病原体得以明确。hMPV支气管炎或肺炎患者,病程多为自限性,继发细菌感染几率较低,治疗往往并不需要抗生素,可采用支持性治疗,目前尚无有效的抗病毒药物。

关键词：人偏肺病毒胸部CT 社区获得性肺炎

Concise Aanlysis on Napoleon and his Forgotten Troop

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海外英语 2014年第5X期 188-189页

作者： JIA yu-kun Hainan University

When talking about Napoleon,people always focus on his military talent,his empire,his famous code or even his final defeat—Battle of *** people will remember his quest for Egypt and his mysterious‘troop’.This thesi... 详细信息

关键词： napoleon the forgotten troop military talent Egypt