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射流管伺服阀龙门式力矩马达AMESim仿真与实验研究

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液压气动与密封 2024年第5期44卷 14-19页

作者：赵小龙姜本九石笑雨张滨朱玉川西安航空动力控制科技有限公司技术中心陕西西安710077 南京航空航天大学机电学院江苏南京210016

射流管电液伺服阀是电液伺服控制系统的核心控制元件,广泛应用于航空航天、舰船等国防军事领域。力矩马达作为射流管电液伺服阀的核心元件,其工作性能直接影响到伺服阀的整体性能。聚焦研究龙门式力矩马达的工作性能,搭建了力矩马达AME... 详细信息

射流管电液伺服阀是电液伺服控制系统的核心控制元件,广泛应用于航空航天、舰船等国防军事领域。力矩马达作为射流管电液伺服阀的核心元件,其工作性能直接影响到伺服阀的整体性能。聚焦研究龙门式力矩马达的工作性能,搭建了力矩马达AMESim仿真模型,仿真研究了龙门式力矩马达的静动态特性,通过实验验证了仿真结果的正确性。研究结果表明,该龙门式力矩马达静态线性度为6.825%,对称度为2.449%,动态阶跃响应的上升时间为2.84 ms,幅频宽为122 Hz,相频宽为245 Hz。

关键词：龙门式力矩马达 AMESim仿真实验静动态特性

一种低寄生参数高功率密度GaN半桥模块研究

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电力电子技术 2024年第8期58卷 121-124页

作者：廖志凌桂久衡王华佳陈兆岭江苏大学电气信息工程学院江苏镇江212000 国网山东省电力公司电力科学研究院山东济南250000

针对高频环境下寄生参数引起氮化镓(GaN)金属氧化物半导体场效应晶体管(MOSFET)开关损耗大的问题,提出一种基于GaN开关器件的半桥电路集成方案。该方案的实现基于寄生参数较低的高功率密度GaN半桥模块(GS66516T),通过有限元分析提取寄... 详细信息

针对高频环境下寄生参数引起氮化镓(GaN)金属氧化物半导体场效应晶体管(MOSFET)开关损耗大的问题,提出一种基于GaN开关器件的半桥电路集成方案。该方案的实现基于寄生参数较低的高功率密度GaN半桥模块(GS66516T),通过有限元分析提取寄生参数联合电气模型参数仿真分析,从而实现驱动电路和功率环路的优化设计。最后,研制一台4kW两相交错并联降压变换器原理样机,并搭建双脉冲测试(DPT)平台用于分析测试实验中寄生参数对开关过程的影响。实验结果表明,该样机可实现功率密度536.19 W/in^(3),峰值效率97.65%,并具有较好的动态开关特性。

关键词：半桥模块寄生参数双脉冲测试

Structure, magnetic properties, and thermal stability of Sm(1-x)Tm_xCo_5compounds

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Rare Metals 2014年第2期33卷 176-179页

作者： Jian-Hua Zuo Ming Yue Qing-Mei Lu Dong-Tao Zhang Xue-Xu Gao jiu-Xing Zhang zhao-Hui Guo Wei Li College of Materials Science and Engineering Beijing University of Technology State Key Laboratory of Advanced Metals and Materials University of Science and Technology Beijing Division of Functional Materials Central Iron and Steel Research Institute

Structure, magnetic properties, and thermal stability of ternary Sm1-xTmxCo5 compounds were studied via X-ray diffraction（XRD）, thermal magnetic analysis（TMA）, and magnetic measurements. XRD results show that all the compounds have a main phase of hexagonal CaCu5-type crystal structure with small amount of impurity phases; increasing Tm content is associated with contraction of the hexagonal unit cell in the direction of the c axis and expansion of the a and b parameters. TMA results indicate that the Curie temperature（TC） of Sm1-xTmxCo5 compounds gets higher with the increase in Tm *** measurements show that both the magnetic anisotropy field（HA） and the magnetization at an applied field of 7 T（M7 T） decrease with the increase of Tm content. However, the thermal stability of both the HAand M7 Tof all the Tm doped compounds is remarkably improved compared with that of the pure SmCo5 compound, leading to the result that both the M7 Tand HAof Sm0.8Tm0.2Co5 .2are higher than those of SmCo5 compound at 473 K, which indicates the good potential of Tm doped compound in the practical applications at elevated temperature.

关键词： Sm1-xTmxCo5 compounds Crystal structure Intrinsic magnetic property Thermal stability

Exploring differentially expressed genes associated with fertility instability of S-type cytoplasmic male-sterility in maize by RNA-seq

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Journal of Integrative Agriculture 2017年第8期16卷 1689-1699页

作者： SU Ai-guo SONG Wei SHI Zi zhao Yan-xin XING Jin-feng ZHANG Ru-yang LI Chun-hui LUO Mei-jie WANG Ji-dong zhao jiu-ran Maize Research Center Beijing Academy of Agriculture and Forestry Sciences/Beijing Key Laboratory of Maize DNA Fingerprinting and Molecular BreedingBeijing 100097P.R.China

The germplasm resources for the S-type male sterility is rich in maize and it is resistant to Bipolaris maydis race T and CI, but the commercial application of S-type cytoplasmic male sterility （CMS-S） in maize hybrid industry is greatly compromised because of its common fertility instability. Currently, the existence of multiple minor effect loci in specific nuclear genetic backgrounds was considered as the molecular mechanism for this phenomenon. In the present study, we evaluated the fertility segregation of the different populations with the fertility instable material FIL-H in two environments of Beijing and Hainan, China. Our results indicated that the fertility instability of FIL-H was regulated by multiple genes, and the expression of these genes was sensitive to environmental factors. Using RNA sequencing （RNA-seq） technology, transcriptomes of the sterile plants and partially fertile plants resulted from the backcross of FIL-HxJing 724 in Hainan were analyzed and 2 108 genes with different expression were identified, including 1 951 up-regulated and 157 down-regulated genes. The cluster analysis indicated that these differentially expressed genes （DEGs） might play roles in many biological processes, such as the energy production and conversion, carbohydrate metabolism and signal transduction. In addition, the path- way of the starch and sucrose metabolism was emphatically investigated to reveal the DEGs during the process of starch biosynthesis between sterile and partially fertile plants, which were related to the key catalytic enzymes, such as ADP-G pyrophosphorylase, starch synthase and starch branching enzyme. The up-regulation of these genes in the partially fertile plant may promote the starch accumulation in its pollen. Our data provide the important theoretical basis for the further exploration of the molecular mechanism for the fertility instability in CMS-S maize.

关键词： CMS-S fertility instability RNA-seq DEGs

Association of three single nucleotide polymorphisms of ESR1 with breast cancer susceptibility:a meta-analysis

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The Journal of Biomedical Research 2017年第3期31卷 213-225页

作者： Xu Hu Linfei Jiang Chenhui Tang Yuehong Ju Li jiu Yongyue Wei Li Guo Yang zhao Department of Biotechnology School of Basic Medical SciencesNanjing Medical UniversityNanjingJiangsu 211166China School of International Pharmaceutical Business China Pharmaceutical UniversityNanjingJiangsu 211198China Department of Biostatistics School of Public HealthNanjing Medical UniversityNanjingJiangsu 211166China School of Geographic and Biologic Information Nanjing University of Posts and TelecommunicationsNanjingJiangsu 210046China

Expression of estrogen receptors is correlated with breast cancer risk,but inconsistent results have been *** clarify potential estrogen receptor（ESR）-related breast cancer risk,we analyzed genetic variants of ESR1 in association with breast cancer *** performed a meta-analysis to investigate the association between rs2234693,rs1801132,and rs2046210（single nucleotide polymorphisms of ESR1）,and breast cancer *** analysis included 44 case-control *** rs2234693,the CC genotype had a higher risk of breast cancer compared to the TT or CT *** rs2046210,the AA,GA,or GA ＋ GG genotype had a much higher risk compared to the GG *** significant association was found for the rs 1801132 polymorphism with breast cancer *** meta-analysis demonstrates association between the rs2234693 and rs2046210 polymorphisms of ESR1 and breast cancer *** correlation strength between rs2234693 and breast cancer susceptibility differs in subgroup assessment by ethnicity.

关键词： breast cancer estrogen receptor alpha meta-analysis single nucleotide polymorphism

Maize grain yield and water use efficiency in relation to climatic factors and plant population in northern China

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Journal of Integrative Agriculture 2021年第12期20卷 3156-3169页

作者： LIU Yue-e HOU Peng HUANG Gui-rong ZHONG Xiu-li LI Hao-ru zhao jiu-ran LI Shao-kun MEI Xu-rong Beijing Key Laboratory of Maize DNA Fingerprinting and Molecular Breeding/Maize Research Center Beijing Academy of Agriculture&Forestry SciencesBeijing 100097P.R.China Key Laboratory of Crop Physiology and Ecology Ministry of Agriculture and Rural Affairs/lnstitute of Crop SciencesChinese Academy of Agricultural SciencesBeijing 100081P.R.China Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural Sciences/Key Laboratory of Dryland Farming AgricultureMinistry of Agriculture and Rural AffairsBeijing 100081P.R.China

Water scarcity has become a limiting factor for increasing crop *** ways to improve water use efficiency(WUE)has become an urgent task for Chinese *** understand the response of different maize populations to changes in precipitation and the effects of changes in maize populations on WUE,this study conducted maize population experiments using maize hybrids with different plant types(compact and semi compact)and different planting densities at 25 locations across *** was found that,as precipitation increased across different locations,maize grain yield first increased and then decreased,while WUE decreased *** the relationship between WUE and the main climatic factors,this study found that WUE was significantly and negatively correlated with precipitation(R(daily mean precipitation)and R(accumulated precipitation))and was positively correlated with temperature(TM(daily mean maximum temperature),T_(M-m)(T_(m),daily mean minimum temperature)and GDD(growing degree days))and solar radiation(Ra(daily mean solar radiation)and Ra(accumulated solar radiation))over different growth *** differences in maize grain yield,WUE and precipitation were found at different planting *** population densities were ranked as follows according to maize grain yield and WUE based on the multi-site experiment data:60000 plants ha^(-1)(P_(2))>90000 plants ha^(-1)(P_(3))>30000 plants ha^(-1)(P_(1)).Further analysis showed that,as maize population increased,water consumption increased significantly while soil evaporation decreased *** differences were found between the WUE of ZD958(compact type)and that of LD981(semi-compact type),as well as among the WUE values at different planting *** addition,choosing the optimum hybrid and planting density increased WUE by 21.70 and 14.92%,respectively,which showed that the hybrid played a more significant role than the planting density in improving WU

关键词： maize climatic factor water utilization characteristics water use efficiency hybrids planting density

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内蒙古三河牛牛肉挥发性风味物质分析

中国牛业科学 2024年第1期50卷 39-49页

作者：程延彬陈军刘文芝赵曼崔久辉栾迪内蒙古呼伦贝尔农垦谢尔塔拉农牧场有限公司内蒙古呼伦贝尔021012 内蒙古呼伦贝尔市疾病预防控制中心内蒙古呼伦贝尔021008 内蒙古呼伦贝尔农垦集团有限公司内蒙古呼伦贝尔021008

旨探寻内蒙古三河牛牛肉风味特征物质,分析不同部位生牛肉中挥发性风味物质种类和含量,以期探索牛肉挥发性风味物质在牛肉中的作用机理。采集呼伦贝尔农垦集团三河牛牛肉16个部位共计48份样品,采用固相微萃取技术联合气相质谱分析仪(SPM... 详细信息

旨探寻内蒙古三河牛牛肉风味特征物质,分析不同部位生牛肉中挥发性风味物质种类和含量,以期探索牛肉挥发性风味物质在牛肉中的作用机理。采集呼伦贝尔农垦集团三河牛牛肉16个部位共计48份样品,采用固相微萃取技术联合气相质谱分析仪(SPME-GC-MS)对三河牛牛肉中挥发性风味物质进行分析研究,挥发性组分通过与NIST20谱库及正构烷烃标准物质进行比对进行定性分析,且正反匹配度均大于800(最大值为1000)的鉴定结果予以确认,通过峰面积归一化法计算各组分的相对含量。结果表明,16个部位中挥发性风味化合物检测出7大类共159种主要挥发性风味物质,其中醛类化合物32种,醇类化合物21种,酸类化合物16种,烃类化合物37种,酯类化合物33种,酮类化合物10种和杂环类化合物11种。三河牛肉质氨基酸含量高、风味口感都非常好,是生产肉制品的高端原料。

关键词：内蒙古三河牛牛肉风味

社区精神分裂症患者社会支持与生活质量的关联——焦虑抑郁症状为中介的探索性研究

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现代预防医学 2024年第17期51卷 3163-3168+3179页

作者：杨琴巫岚秦小荣胡萱怡熊朝新宇陈玥雷小莉易博何昌九成都市第四人民医院社区防治部四川大学华西公共卫生学院/华西第四医院

目的调查社区精神分裂症患者（简称精分患者）中社会支持、生活质量、焦虑抑郁症状之间的关联与特征以及探索焦虑抑郁症状在社会支持和生活质量之间的中介作用。方法采用多阶段分层整群随机抽样的方法选取出四川省成都市的几个区县共1... 详细信息

目的调查社区精神分裂症患者（简称精分患者）中社会支持、生活质量、焦虑抑郁症状之间的关联与特征以及探索焦虑抑郁症状在社会支持和生活质量之间的中介作用。方法采用多阶段分层整群随机抽样的方法选取出四川省成都市的几个区县共1 106例社区精分患者，采用问卷调查的方法进行调查，调查问卷包括社会支持量表(SSRS)、抑郁症筛查量表(PHQ-9)、广泛性焦虑自评量表(GAD-7)、生活质量(QOL)评价，先对精分患者的人口学资料和精神疾病相关信息进行统计描述，再对精分患者生活质量、社会支持总分及焦虑、抑郁得分的相关性分析，最后采用bootstrap法对焦虑抑郁症状在社会支持影响生活质量进行中介分析。结果本次调查获得有效问卷1 087份。社区精分患者生活质量躯体健康总分(72.01±20.99)分，心理健康总分(71.68±19.38)分，社会支持总分为(28.27±7.08)分，焦虑症状得分为(3.14±4.39)分，抑郁症状得分为(4.61±5.05)分。Pearson相关分析结果显示，社区精分患者社会支持总分与生活质量的躯体健康和心理健康两个维度得分均呈正相关(P<0.05)，与焦虑、抑郁得分呈现负相关(P<0.05)。焦虑和抑郁得分与生活质量的两个维度均呈现负相关关系(P<0.05)。中介效应模型显示，抑郁在社会支持总分影响躯体健康和心理健康中均起到完全中介的作用，中介效应占比分别为33.60%(P<0.01)和47.81%(P<0.01)。焦虑在社会支持总分对于生活质量的影响中的中介效应不显著。结论早期识别出患者的抑郁症状，建立广泛的社会支持，降低患者负面情绪，并采取措施积极地改善病情，促进患者生活质量的提高。

关键词：精神分裂症社会支持生活质量焦虑抑郁中介效应

Improving capacity building by implementing comprehensive eye care project,experiences from Kuandian County,China

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Chinese Medical Journal 2005年第22期118卷 1925-1928页

作者： LIN Yan YU Yong-jiu zhao Zhi-yan Advisory Center for Social Service China Rehabilitation Research Center China Disabled Person＇ s Federation Beijing 100068China Department of Ophthalmology First Hospital of Kuandian County Kuandian 118200 China

The global campaign “Vision 2020： The Right to Sight” was officially launched in Geneva byDr. Gro Harlem Brundtland, the Director General of World Health Organization （ WHO ） in February 1999. This represents the global initiative for the elimination of avoidable blindness by the year 2020.1 Seven months later, the International Agency for the Prevention of Blindness （IAPB） General Assembly was held in Beijing, China. During the IAPB General Assembly, the Chinese Ministry of Health, China Disabled Person＇ s Federation together with WHO launched the national campaign “Vision 2020： The Right to Sight” in China.

关键词： eye care Vision 2020 · prevention · blindness · capacity building