检索结果-南通市图书馆

Journal of Materials Science & Technology 2010年第1期26卷 93-96页

作者： yangping Li and Zhengtang Liu School of Materials Science and Engineering, Northwestern Polytechnical University, Xi an 710072, China School of Materials Science and Engineering Northwestern Polytechnical University Xi'an 710072 China

Radio-frequency （RF） magnetron sputtering was employed to prepare gallium phosphide （GAP） thick films on zinc sulfide （ZnS） substrates by sputtering a single crystalline GaP target in an Ar atmosphere. The infrared （IR） transmission properties, structure, morphology, composition and hardness of the film were studied. Results show that both amorphous and zinc-blende crystalline phases existed in the GaP film in almost stoichiometric amounts. The GaP film exhibited good IR transmission properties, though the relatively rough surface and loose microstructure caused a small loss of IR transmission due to scattering. The GaP film also showed a much higher haraness than the ZnS substrate, thereby providing good protection to ZnS.

关键词： Radio-frequency magnetron sputtering Gallium phosphide Thick film Infrared transmission

基于复杂背景的多尺度特征融合手-物交互检测方法

在线全文

学校读者我要写书评

暂无评论

兰州交通大学学报 2024年第5期43卷 94-102页

作者：王文润党建武王阳萍梁超兰州交通大学电子与信息工程学院兰州730070 兰州交通大学轨道交通信息与控制国家级虚拟仿真实验教学中心兰州730070 甘肃省人工智能与图形图像处理工程研究中心兰州730070

针对手与物体在交互过程中不同场景的背景噪声、光照变化等复杂背景,以及手-物相互遮挡、分辨率低等问题对手-物交互检测精度的影响,提出采用一种两阶段的多尺度特征融合手-物交互检测方法。首先,引入基于特征金字塔的残差网络Resnet50... 详细信息

针对手与物体在交互过程中不同场景的背景噪声、光照变化等复杂背景,以及手-物相互遮挡、分辨率低等问题对手-物交互检测精度的影响,提出采用一种两阶段的多尺度特征融合手-物交互检测方法。首先,引入基于特征金字塔的残差网络Resnet50作为特征提取主干网络,实现深层语义信息和浅层细节特征的多尺度融合,提高小目标检测的精度;然后,利用检测到的手部区域与物体区域的几何信息来判断是否交互,过滤非交互的物体;最后,在大规模的室内外包括11个类别的手接触物体的人类互动视频帧数据集进行实验,提高网络的泛化性能。实验结果表明,本文所提方法和两阶检测方法相比,在提高检测精度的同时没有增加网络模型复杂度,同时在数据集不同类别的检测精度相对稳定,有效提升了网络的泛化性能。

关键词：手物交互目标检测复杂背景多尺度特征融合

Three-dimensional dissipative stress space considering yield behavior in deviatoric plane

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2013年第11期56卷 1999-2009页

作者： YAO yangping CUI WenJie WANG NaiDong School of Transportation Science and Engineering Beihang University

Naturally deposited soils are always found in the complex three-dimensional stress *** models developed for modeling the three-dimensional mechanical behavior of soils should obey the basic laws of thermo-mechanical *** on the incremental dissipation function,a new deviatoric shift stress is derived and then introduced into the existing constitutive models to describe the yield behavior in the deviatoric plane for *** adopting the proposed shift stress,the relationship between dissipative stress tensors and true stress tensors can be ***,the threedimensional plastic strain can be calculated reasonably through the associated flow rule in the three-dimensional dissipative stress *** the same time,three methods that are conventionally adopted for generalizing constitutive models to model the three-dimensional stress-strain relationships are examined under the thermo-mechanical *** TS(transformed stress)method is shown to obey the thermo-mechanical rules and the TS space adopted in TS method is actually a translational three-dimensional dissipative stress ***,it is illustrated that the other two approaches,the method of using failure criterion directly and the method of using g()function,violate the basic rules of thermo-mechanical theories although they may bring convenience and simplicity to numerical analysis for geotechnical *** between model predictions and experimental data confirms the validity of the proposed three-dimensional dissipative stress space.

关键词： soils thermo-mechanics yield behavior shift stress stress space three-dimension

Studies on the effects of pre-firing and sintering temperature on NSDC nanocomposite electrolytes

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2022年第1期32卷 128-134页

作者： Saddam Hussain yangping Li Fida Hussain Memon Sabir Hussain Lei Li Khalid Hussain Thebo State Key Laboratory of Solidification Processing School of Materials Science and Engineering Northwestern Polytechnical University Department of Electrical Engineering Sukkur IBA University Department of Space Science University of the Punjab University of Chinese Academy of Sciences

Solid oxide fuel cells（SOFCs） technology, with fuel flexibility, is one of the most promising power generation technology. However, the high operating temperature of SOFCs has hindered their commercial applications. As a crucial requirement to enhance its performance, SOFCs electrolytes should operate at a low temperature. Carbonate/ceria composites are developed as electrolytes for low operating temperature SOFCs, and a better understanding of the mechanism of its ionic conductivity serves this purpose. In this work, ceria-carbonate composite electrolyte, Na;CO;/samarium doped ceria（NSDC） were synthesized by the co-precipitation *** synthesized electrolytes were characterized by X-ray diffraction（XRD）, scanning electron microscopy（SEM）,X-ray photoelectron spectroscopy（XPS）, and UV–Vis spectroscopy. The XRD and SEM results showed that the sintered NSDC nanocomposite comprised a single-phase dense electrolyte structure. The crystallite size of the NSDC nanocomposite was greatly affected by the different pre-firing temperatures and different sintering temperatures. Also, the ionic conductivity of the prepared NSDC nanocomposite electrolytes was strongly dependent on the pre-firing and sintering temperatures. The NSDC nanocomposite electrolytes were pre-fired at 950°C and650°C and sintered at 1200°C and 900°C respectively, had ionic conductivity in H;and air high as 0.36 S/cm and 0.3 S/cm.

关键词： Solid oxide fuel cell NDSC Composite Electrolyte Ionic conductivity

虾夷扇贝F_(1)自交衰退及其遗传调控机理

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

水产科学 2024年第1期43卷 1-9页

作者：赵亮李仰平高杉姜苹哲林杉杉张国瀚范广其蒋经伟周遵春辽宁省海洋水产科学研究院辽宁大连116023 农业农村部水产种质资源保护与发掘利用重点实验室辽宁大连116023 辽宁省海洋水产动物种质改良与优良苗种繁育重点实验室辽宁大连116023 中国海洋大学山东青岛266100

近交导致的种质退化严重影响虾夷扇贝养殖产业。为探明虾夷扇贝近交衰退的现象及遗传调控机理,在表型水平上,构建近交系数分别为0.5、0.25和0的自交组、近交组与自然群体对照组,追踪不同近交系数下虾夷扇贝幼虫期到成体期530日龄的性状... 详细信息

近交导致的种质退化严重影响虾夷扇贝养殖产业。为探明虾夷扇贝近交衰退的现象及遗传调控机理,在表型水平上,构建近交系数分别为0.5、0.25和0的自交组、近交组与自然群体对照组,追踪不同近交系数下虾夷扇贝幼虫期到成体期530日龄的性状差异,同时选取7个适合度性状,利用主成分分析法构建基于近交衰退的适合度指标评价方法;在基因组水平上,利用1个自交家系的亲本及其21个子代进行全基因组重测序,开展标记偏分离分析。试验结果显示:针对存活率性状,在幼虫期,自交组近交衰退率是近交组的1.31~3.05倍;在成体期,自交组近交衰退率是近交组的0.97~7.29倍。而生长性状,在幼虫期,仅有自交组保持较低的近交衰退率(1.65%~2.56%);在成体期,自交组与近交组几乎未发生衰退。基于重测序分型得到1253519个单核苷酸多态性用于偏分离统计,约99%在子代中发生了显著的偏分离,其中23%属于配子偏分离、77%属于合子偏分离,合子偏分离中有89%为杂合子过剩,即超显性效应起作用,仅10%受显性效应影响为纯合子缺失。试验结果表明,超显性效应及偏分离作用在虾夷扇贝F_(1)子代存活率性状的自交衰退中起主要作用,为近交衰退的机理提供更有力证据的同时,也为虾夷扇贝种质遗传改良提供了有效思路。

关键词：虾夷扇贝自交适合度偏分离近交衰退

Electroacupuncture stimulating Neixiyan(EX-LE5)and Dubi(ST35)alleviates osteoarthritis in rats induced by anterior cruciate ligament transaction via affecting DNA methylation regulated transcription of miR-146a and miR-140-5p

在线全文

学校读者我要写书评

暂无评论

中医杂志:英文版 2023年第5期43卷 983-990页

作者： DING Luobin WANG Huajun LI Yao LI Jia LI Ling GAO yangping GUAN Jian GENG Weiqiang Department of Orthopedics the Third Hospital of ShijiazhuangShijiazhuang 050011China Department of Orthopedic Surgery and Sports Medicine Center the First Affiliated HospitalJinan UniversityGuangzhou 510630China Division of Rheumatology Guangdong Provincial People’s HospitalGuangdong Academy of Medical SciencesGuangzhou 510080China Department of TCM Orthopedics and Traumatology the Third Affiliated Hospital of Southern Medical UniversityGuangzhou 510630China Department of Orthopedic Surgery No.980 HospitalJoint Logistics Support Force People's Liberation Army(PLA)Handan Campus of Bethune International HospitalHandan 050082China

OBJECTIVE:To explore whether electroacupuncture(EA could alleviate osteoarthritis(OA)through affecting the DNA methylation regulated transcription of miR-146a and mi ***:Sixty male eight-week-old Sprague-Dawley rats were divided into three groups:normal group(normal healthy rats;no treatment),model group(OA rats;no treatment)and EA group(OA rats treated with EA).Safranin O staining and modified Mankin’s score were performed to evaluate the histopathological alterations and degeneration of cartilage 8 weeks after 8 consecutive weeks of *** real time polymerase chain reaction(qR T-PCR)assay was employed to evaluate the expression of miR-146a in the cartilage tissue and miR-140-5p in the synovium tissue,*** bisulfite sequencing analysis and quantitative methylation specific PCR(qMSP)were used to analyze the status of methylation in the regulatory regions of miR-146a and *** immunoprecipitation(ChIP)assay were performed to assess the binding of nuclear factor-kappa B(NF-κB)and signal transducer and activator of transcription 3(SMAD-3)in the regulatory regions of miR-146a and *** blot analysis was performed to detect the expressions of DNA Methyltransferase 1(DMNT1),DNA Methyltransferase 3A(DMNT3A),and DNA Methyltransferase 3A(DMNT3b),NF-κB,SMAD3 ***:Our results showed that EA treatment significantly upregulated miR-146a and miR-140-5p *** analysis showed that EA significantly decreased methylation levels of miR-140-5p regulated region and miR-146a promoter in OA cartilage and *** DNA sequencing(BDS)and ChI P analysis showed that EA significantly increased binding affinity of SMAD3 and NF-kB on the hypermethylated miR-140 regulatory region and miR-146a promoter,*** Blot analysis demonstrated that EA also significantly decreased expressions of methylation related proteins-DMNT1,DMNT3a,and DMNT3b as well as NF-κB and ***:Electro

关键词： osteoarthritis,knee electroacupuncture DNA methylation MicroRNAs

在线全文

学校读者我要写书评

暂无评论

医院航空医疗救护能力建设的实践与探索

现代医院 2024年第1期24卷 107-110,113页

作者：张泰辉吴耿马晋平冯锦涛刘阳萍中山大学附属第一医院广东广州510062

本文结合航空医疗救护的特点及行业发展现状,分析了医院发展航空医疗救护能力的重难点,针对性地提出了由规划制度、服务模式、专业队伍、硬件平台、运行流程五大模块组成的建设框架,梳理了各模块的重点工作内容,分享了中山大学附属第一... 详细信息

本文结合航空医疗救护的特点及行业发展现状,分析了医院发展航空医疗救护能力的重难点,针对性地提出了由规划制度、服务模式、专业队伍、硬件平台、运行流程五大模块组成的建设框架,梳理了各模块的重点工作内容,分享了中山大学附属第一医院在航空医疗救护能力建设上的探索与实践经验,旨在为现代医院发展航空医疗救护能力提供参考。

关键词：航空医疗救护体系建设

用于深地核天体物理实验的无窗气体靶差分结构和热效应研究

在线全文

学校读者我要写书评

暂无评论

原子能科学技术 2024年第S1期58卷 1-8页

作者：蒋宇辰连钢方晓李云居曹富强南巍曾晟谌阳平柳卫平中国原子能科学研究院北京102413 中山大学中法核工程与技术学院广东珠海519082 南方科技大学广东深圳518055

我国锦屏深地核天体物理(JUNA)平台是世界上束流强度最高的深地实验平台,为我国争取核天体物理国际领先地位提供了重要机遇。无窗气体靶是深地低能核天体物理实验测量的关键设备,可实现特定同位素参与核反应的直接测量,能有效拓展深地... 详细信息

我国锦屏深地核天体物理(JUNA)平台是世界上束流强度最高的深地实验平台,为我国争取核天体物理国际领先地位提供了重要机遇。无窗气体靶是深地低能核天体物理实验测量的关键设备,可实现特定同位素参与核反应的直接测量,能有效拓展深地实验的研究范围。国际上已有多家实验室将无窗气体靶应用于低能核反应的研究,但针对的都是较低流强的实验。为适应锦屏高功率强束流的实验需求,本工作设计可用于强流束的气体靶装置。通过Ansys Fluent和COMSOL软件模拟计算,验证了多级差分结构的可行性,并研究了靶厚的束流加热效应和量热器热效应,提出了无窗气体靶实验的设计优化方案,为后续JUNA深地实验研究的发展提供了可靠依据。

关键词：核天体物理深地实验室无窗气体靶低能核反应

A Population Genetic Analysis of Continuously Selected Chlamys farreri Populations

在线全文

学校读者我要写书评

暂无评论

Journal of Ocean University of China 2018年第4期17卷 913-919页

作者： ZHANG Lu LI Yuli LI yangping YANG Zhihui LI Yuqiang WANG Yangfan WANG Shi BAO Zhenmin Key Laboratory of Marine Genetics and Breeding (MGB) of Chinese Ministry of Education College of Marine Life Sciences Ocean University of China

This study applied an optimized one-step 2b-RAD library construction strategy and performed simplified genome sequencing of 539 individuals from three continuously selected Chlamys farreri populations. SNP screening was performed using RAD typing software and population genetic parameters for the continuously selected populations from three generations(G1, G2, G3) were determined. The results showed that the optimized one-step 2b-RAD library construction strategy greatly simplified the experimental process, making it suitable for efficiently constructing a large number of libraries. A total of 18450 SNP markers were identified, which evenly distributed throughout the genome. Population genetic analysis of these three generations showed that the mean value of observed heterozygosity was 0.275 ± 0.177, 0.272 ± 0.181 and 0.275 ± 0.166, respectively. Meanwhile, the mean value of expected heterozygosity was 0.275 ± 0.141, 0.274 ± 0.145 and 0.280 ± 0.133, respectively. The Wright's fixation index(F) was 0.04291, 0.04976 and 0.06685, respectively. Markers deviated from Hardy–Weinberg equilibrium accounted for 10.34%, 12.64%, and 23.11%, and the Shannon diversity index was 0.0999 ± 0.0404, 0.0921 ± 0.0388 and 0.0733 ± 0.0308. FIS(also known as the inbreeding coefficient) of the three populations was 0.0256, 0.0323 and 0.0468, respectively. We suggested that the 2b-RAD method is well suited to population genetic studies of aquacultured organisms. Moreover, our results indicated that the continuous selection affected the population genetic structure of the cultured Penglai-Red scallop, but the change was not significant; therefore, population selection should continue.

关键词： 2b-RAD population genetic Chlamys farreri SNP

基于MaxEnt模型的云南省华山松潜在适生区研究

在线全文

学校读者我要写书评

暂无评论

林业调查规划 2024年第5期49卷 24-31页

作者：李华覃阳平罗春林杨海方侯文通国家林业和草原局西南调查规划院云南昆明650031 云南金杉工程建设监理咨询有限公司云南昆明650051

基于535个华山松物种分布点和33个环境变量数据,利用最大熵模型(MaxEnt)和ArcGIS软件模拟华山松潜在适生区及影响其分布的主要环境变量,并通过受试者工作特征曲线对模型精度进行验证。结果表明,华山松MaxEnt模型十折交叉验证的AUC值为0.... 详细信息

基于535个华山松物种分布点和33个环境变量数据,利用最大熵模型(MaxEnt)和ArcGIS软件模拟华山松潜在适生区及影响其分布的主要环境变量,并通过受试者工作特征曲线对模型精度进行验证。结果表明,华山松MaxEnt模型十折交叉验证的AUC值为0.832,标准差为±0.019,表明模型模拟效果较好且具有较高的稳定性;影响华山松潜在适生区的主要环境变量为年均温、昼夜温差月均值、温度的季节性、最暖季降水量、最冷季降水量和土壤pH,其中年均温是影响华山松潜在分布最重要的环境变量,其适宜区间介于6.6~14.8℃;华山松潜在适生区在云南省主要分布于滇东北、滇中和滇西北地区,全省高、中、低适生区面积分别为65596、40142和46154 km^(2);曲靖市高、中适生区面积最大,迪庆州低适生区面积最大,西双版纳州无华山松适生区。

关键词：华山松潜在适生区 MaxEnt模型环境变量