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Characterization of Nanocrystallizatin Surface Layer of 0.4C-1Cr Low Alloy Steel Prepared by Ultrasonic Particulate Peening

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材料热处理学报 2004年第05B期25卷 1257-1259页

作者： zhangjun-bao LIUYu-liang ZHAOXin-qi WUJie SONGHong-wei XIONGTian-ying baosteelTechnologyCenter BaoshanIron＆SteelCO.LTD.ShanghaiChina InstituteofMetalResearch ChineseAcademyofSciencesShenyangChina

A nanostructured surface layer was fabricated in a quenched and tempered 0.4C-lCr low alloy steel by ultrasonic particulate peening technique. The microstructure of the nanocrystalline surface layer was characterized by means of TEM and Mossbauer spectroscopy. Experimental results reveal that both cementite and ferrite nanocrystals with an average size of 5 nm were formed in the surface layer of the steel, phase transformation of austenite and dissolution of cementite maybe occur in the process of ultrasonic paniculate peening.

关键词：显微结构超声波喷丸处理表面毫微结晶 0.4C-1Cr低合金钢

卷边PEC柱(弱轴)-钢梁组合框架层间抗震机理试验研究

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河海大学学报（自然科学版） 2016年第4期44卷 309-316页

作者：冯进包张君方有珍王玉玺苏州科技大学江苏省结构重点实验室江苏苏州215011

为揭示新型卷边PEC柱(弱轴)-削弱截面钢梁组合框架结构的层间抗震机理,按1∶2缩尺比例设计制作1榀组合框架层间子结构试验试件并进行低周往复荷载试验。基于试验观察和数据整理,对试件结构的破坏过程与破坏模式、滞回特性、刚度退化、... 详细信息

为揭示新型卷边PEC柱(弱轴)-削弱截面钢梁组合框架结构的层间抗震机理,按1∶2缩尺比例设计制作1榀组合框架层间子结构试验试件并进行低周往复荷载试验。基于试验观察和数据整理,对试件结构的破坏过程与破坏模式、滞回特性、刚度退化、耗能能力与变形模式等抗震性能进行分析。结果显示:试件结构最终破坏模式为梁端削弱截面处充分屈服形成塑性铰的理想塑性破坏机构;试件中间层推拉方向位移延性系数μu分别为3.91和3.97,层间最大等效黏滞阻尼系数(ζeq)max=0.359;试件结构侧移分布规律呈理想的倒三角弯剪型变形模式;试件结构在承载力下降到极限承载力的85%时,对应试件层间相对侧移大于4.9%,而节点转角最小值为0.366 rad,均超过大震层间侧移限值下限的1/30,表明试件具有良好的抗倒塌性能。

关键词：新型PEC柱削弱截面梁组合框架层间子结构低周往复荷载试验抗震机理

部分外包混凝土组合柱-钢梁T形连接件连接框架层间抗震机理研究

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建筑结构学报 2015年第12期36卷 35-42页

作者：方有珍顾强孙国华包张君钮荣斌苏州科技学院江苏省结构工程重点实验室江苏苏州215011

为研究T形连接件连接的新型卷边部分外包混凝土组合柱-钢梁组合框架层间抗震机理,按1/2缩尺设计制作了1榀组合框架中间层子结构模型试件,并进行水平低周反复荷载试验。基于试验结果,分析了组合框架中间层子结构的滞回特性、承载力、抗... 详细信息

为研究T形连接件连接的新型卷边部分外包混凝土组合柱-钢梁组合框架层间抗震机理,按1/2缩尺设计制作了1榀组合框架中间层子结构模型试件,并进行水平低周反复荷载试验。基于试验结果,分析了组合框架中间层子结构的滞回特性、承载力、抗侧刚度退化、耗能能力和破坏模式等。结果表明:T形连接件连接实现了"小震利用摩擦耗能,中大震通过梁端屈服耗能"的设计目标;预拉对穿螺栓连接有效实现了节点域混凝土斜压带传力模式,且T形连接件的设置使梁端出现塑性铰位置外移,更好满足了"强节点弱构件"的抗震要求;试件抗侧刚度沿高度分布均匀,试件整体水平位移表现为理想的倒三角弯剪型变形模式;试件的破坏模式为中间层T形连接件端部外排螺栓附近梁截面形成塑性铰的塑性破坏机构,对应层间侧移角和节点连接转角均达到0.05 rad,超过了罕遇地震作用下层间侧移角限值1/30的要求,且试件承载力仍呈缓慢增大趋势,即结构具有良好的抗倒塌性能。

关键词：组合框架层间子结构部分外包混凝土组合柱 T形连接件拟静力试验抗震机理

卷边PEC柱-钢梁(BRS)端板连接组合框架中间层抗倒塌机理数值模拟

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防灾减灾工程学报 2016年第2期36卷 239-246页

作者：包张君方有珍沈晓明王玉玺王辰宇苏州科技学院江苏省结构重点实验室江苏苏州215011 苏州市吴中建筑工程施工图审查中心江苏苏州215128

为研究卷边PEC柱-钢梁组合框架中间层抗倒塌机理,以采用端板预拉对穿螺栓连接的新型卷边钢板组合截面PEC柱(弱轴)-钢梁(BRS)组合框架中间层子结构试验试件作为研究对象,利用有限元软件ABAQUS对其进行水平低周往复荷载下倒塌机理的数值... 详细信息

为研究卷边PEC柱-钢梁组合框架中间层抗倒塌机理,以采用端板预拉对穿螺栓连接的新型卷边钢板组合截面PEC柱(弱轴)-钢梁(BRS)组合框架中间层子结构试验试件作为研究对象,利用有限元软件ABAQUS对其进行水平低周往复荷载下倒塌机理的数值模拟。基于计算数据,对比分析试件承载力、抗侧刚度、连接性能、耗能能力、剪力分配、变形模式、节点传力机理和破坏机构等抗震性能。结果显示:试件具有较大的承载能力和初始抗侧刚度;卷边PEC框架柱平均分担层间水平剪力,层间变形表现为剪切型变形模式;预拉对穿螺栓实现了部分自复位功效,而梁截面削弱满足了连接的转动能力和结构耗散地震能的需求;试件最终破坏模式为梁端削弱截面处出现塑性铰而使结构形成塑性机构,相应连接转角和试件中间层层间剪切角均超过中震层间侧移限值1/50,表明该结构体系具有良好抗震延性和抗倒塌性能。

关键词：卷边PEC柱组合框架中间层子结构抗震机理水平低周反复荷载数值模拟

INVERSE METHOD TO DETERMINE SOIL HYDRAULIC PROPERTIES FROM TRANSIENT OUTFLOW EXPERIMENTS

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Journal of Hydrodynamics 2004年第6期16卷 675-680页

作者： zhangjun XUShao-hui LIUJian-li ZHANGJia-bao InstituteofSoilScience ChineseAcademyofSciencesNanjing210008China

Transient outflow experiments coupling with an inverse method are promisingto derive soil hydraulic information. The water retention curves obtained from one-step andmulti-step outflow experiments were compared with those from the pressure cell method. We found thatin one-step experiments the increment of pressure would reduce the non-uniqueness of inversetechnique and that in multi-step experiment the combination of cumulative outflow with pressure headin the objective function would improve the final estimation and also reduce the non-uniqueness ofinverse problem.

关键词： inverse method hydraulic properties one-step outflow experiment multi-stepoutflow experiment

Genetic characterization of melon accessions in the U.S. National Plant Germplasm System and construction of a melon core collection

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Molecular Horticulture 2021年第1期1卷 72-84页

作者： Xin Wang Kaori Ando Shan Wu Umesh K.Reddy Prabin Tamang Kan bao Sue A.Hammar Rebecca Grumet James D.McCreight zhangjun Fei Boyce Thompson Institute Cornell UniversityIthacaNY 14853USA U.S.Department of Agriculture-Agricultural Research Service Crop Improvement and Protection Research UnitSalinasCA 93905USA Nunhems USA IncAcampoCA 95220USA Gus R.Douglass Institute and Department of Biology West Virginia State UniversityInstituteWV 25112USA U.S.Department of Agriculture-Agricultural Research Service Natural Products Utilization Research UnitThad Cochran Research CenterP.O.Box 1848OxfordMS 38677USA Department of Horticulture Michigan State UniversityEast LansingMI 48824USA U.S.Department of Agriculture-Agricultural Research Service Robert W.Holley Center for Agriculture and HealthIthacaNY 14853USA.

Melon(*** L.)is an economically important vegetable crop cultivated *** melon collection in the *** Plant Germplasm System(NPGS)is a valuable resource to conserve natural genetic diversity and provide novel traits for melon *** we use the genotyping-by-sequencing(GBS)technology to characterize 2083 melon accessions in the NPGS collected from major melon production areas as well as regions where primitive melons *** structure and genetic diversity analyses suggested that *** *** was firstly introduced from the centers of origin,Indian and Pakistan,to Central and West Asia,and then brought to Europe and *** *** from East Asia was likely derived from *** *** in India and Pakistan and displayed a distinct genetic background compared to the rest of *** accessions from other geographic *** developed a core collection of 383 accessions capturing more than 98%of genetic variation in the germplasm,providing a publicly accessible collection for future research and genomics-assisted breeding of ***-five morphological characters investigated in the core collection indicated high variability of these characters across accessions in the ***-wide association studies using the core collection panel identified potentially associated genome regions related to fruit quality and other horticultural *** study provides insights into melon origin and domestication,and the constructed core collection and identified genome loci potentially associated with important traits provide valuable resources for future melon research and breeding.

关键词： Melon C.melo Germplasm Genetic characterization Core collection Genome-wide association study

The USDA cucumber (Cucumis sativus L.) collection: genetic diversity, population structure, genome-wide association studies, and core collection development

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Horticulture Research 2018年第1期5卷 236-248页

作者： Xin Wang Kan bao Umesh K.Reddy Yang Bai Sue A.Hammar Chen Jiao Todd C.Wehner Axel O.Ramírez-Madera Yiqun Weng Rebecca Grumet zhangjun Fei Boyce Thompson Institute Cornell UniversityIthacaNY14853USA Gus R.Douglass Institute and Department of Biology West Virginia State UniversityInstituteVirginiaWV25112USA Department of Horticulture Michigan State UniversityEast LansingMI48824USA Horticultural Science Department North Carolina State UniversityRaleighNC27695USA Horticulture Department University of WisconsinMadisonWI53706USA USDA-ARS Vegetable Crops Research Unit MadisonWI53706USA USDA-ARS Robert W.Holley Center for Agriculture and Health IthacaNY14853USA

Germplasm collections are a crucial resource to conserve natural genetic diversity and provide a source of novel traits essential for sustained crop *** collection,preservation and utilization of these materials depends upon knowledge of the genetic variation present within the *** we use the high-throughput genotyping-by-sequencing(GBS)technology to characterize the United States National Plant Germplasm System(NPGS)collection of cucumber(Cucumis sativus L.).The GBS data,derived from 1234 cucumber accessions,provided more than 23 K high-quality single-nucleotide polymorphisms(SNPs)that are well distributed at high density in the genome(~1 SNP/10.6 kb).The SNP markers were used to characterize genetic diversity,population structure,phylogenetic relationships,linkage disequilibrium,and population differentiation of the NPGS cucumber *** results,providing detailed genetic analysis of the *** collection,complement NPGS descriptive information regarding geographic origin and phenotypic *** also identified genome regions significantly associated with 13 horticulturally important traits through genome-wide association studies(GWAS).Finally,we developed a molecularly informed,publicly accessible core collection of 395 accessions that represents at least 96%of the genetic variation present in the ***,the information obtained from the GBS data enabled deep insight into the diversity present and genetic relationships among accessions within the collection,and will provide a valuable resource for genetic analyses,gene discovery,crop improvement,and germplasm preservation.

关键词： sustained collection structure

瘢痕子宫再次妊娠产妇行椎管内分娩镇痛的效果

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临床麻醉学杂志 2019年第6期35卷 537-539页

作者：张俊洪啸天鲍静影安徽省马鞍山市妇幼保健院麻醉科

目的观察瘢痕子宫再次妊娠产妇行椎管内分娩镇痛的安全性和有效性。方法选择2017年5月至2018年4月我院收治的瘢痕子宫再次妊娠同意阴道试产单胎足月头位产妇101例,随机选取分娩镇痛产妇70例为观察组,其中硬膜外分娩镇痛(E组)36例,腰-硬... 详细信息

目的观察瘢痕子宫再次妊娠产妇行椎管内分娩镇痛的安全性和有效性。方法选择2017年5月至2018年4月我院收治的瘢痕子宫再次妊娠同意阴道试产单胎足月头位产妇101例,随机选取分娩镇痛产妇70例为观察组,其中硬膜外分娩镇痛(E组)36例,腰-硬联合分娩镇痛(C组)34例,同期未镇痛产妇31例为对照组(N组)。记录产妇各产程时间、出血量、新生儿1、5 min Apgar评分、阴道分娩、产钳助产、子宫破裂情况,记录镇痛前、给药后5、10、20 min产妇NRS评分和Bromage评分。结果与N组比较,E组和C组第二产程时间明显延长(P<0.05);E组出血量高于N组及C组,但差异无统计学意义。三组第一、第三产程时间、新生儿1、5 min Apgar评分、阴道分娩、产钳助产、子宫破裂发生率差异无统计学意义;镇痛后E组和C组NRS评分均呈下降趋势。与E组比较,C组NRS评分明显降低(P<0.05)。结论瘢痕子宫再次妊娠产妇采用椎管内分娩镇痛安全可行,不降低阴道分娩率,不增加出血量以及产钳助产、子宫破裂发生率。腰-硬联合分娩镇痛较硬膜外分娩镇痛的镇痛效果好。

关键词：瘢痕子宫再次妊娠阴道分娩硬膜外阻滞腰-硬联合阻滞分娩镇痛

健康服务机器人室内导航视觉传感器研究与开发

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计算机测量与控制 2019年第6期27卷 271-275页

作者：孙宝杨世恩彭章君西南科技大学计算机科学与技术学院

针对健康服务机器人室内导航的应用需求,设计出一种基于STM32F429的嵌入式导航视觉传感器,内嵌500万像素CMOS图像传感器和拥有高性能无线SOC的ESP8266,此次开发的视觉传感器,不是一般的CMOS图像传感器,而是综合了图像感知、图像处理、... 详细信息

针对健康服务机器人室内导航的应用需求,设计出一种基于STM32F429的嵌入式导航视觉传感器,内嵌500万像素CMOS图像传感器和拥有高性能无线SOC的ESP8266,此次开发的视觉传感器,不是一般的CMOS图像传感器,而是综合了图像感知、图像处理、无线通信及节电唤醒等等功能于一体的智能化微型装置,即眼睛加大脑;测试,该导航视觉传感器能够以每秒3次的速度向服务机器人发送位置,完全满足室内移动机器人的移动需求。

关键词：健康服务机器人视觉传感器导航与定位无线通信技术