检索结果-南通市图书馆

Acta Metallurgica Sinica(English Letters) 2022年第1期35卷 49-66页

作者： Guang Zeng Shiqian Liu Qinfen Gu Zebang Zheng Hideyuki Yasuda Stuart d.Mcdonald Kazuhiro Nogita School of Materials Science and Engineering Central South UniversityChangsha 410083China Nihon Superior Centre for the Manufacture of Electronic Materials(NS CMEM) School of Mechanical and Mining EngineeringThe University of QueenslandBrisbaneQLD 4072Australia Graduate School Shenzhen Technology UniversityShenzhen 515118China Australian Synchrotron ANSTO.800 Blackburn RdClaytonVIC 3168Australia State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China department of Materials Science and Engineering Kyoto UniversitySakyo‑kuKyoto 606‑8501Japan

It is widely accepted that further development of Pb-free solder alloys for improved processing and in-service properties of next-generation electronics,can be accelerated through a fundamental understanding of phase transformation and microstructure control in Pb-free solder *** characterization techniques including synchrotron radiation provide a comprehensive toolset to measure the composition,crystallography,morphology,and properties of the major components of solder *** research using such techniques is reviewed in detail including the characterization of the eff ects of microalloy additions on the microstructure and properties of Pb-free solder joints,especially those on the intermetallic *** discoveries outlined are of scientific and industrial relevance and have implications for new solder alloy composition design and the reliability of lead-free solder joints.

关键词： Cu_(6)Sn_(5)intermetallic Synchrotron radiation Solidification Phase transformation

devonian Stratigraphy of the Poshi Area,with a Special discussion on the Stratigraphical Position of the devonian Fish-bearing Series d Eastern Yunnan

在线全文

学校读者我要写书评

暂无评论

地质学报 1949年第Z1期 75-84页

作者： C.w.KU (Southwest Associated University, Geological Survey of Yunnan and Geological Survey of China)

Since the publication of H. C. wang’s [14] paper on the stratigraphical position of the devonian fish-bearing series of E Yunnan, a general agreement seems to be arrived at among Chinese geologists. Recently, however, C. S. Pien [22] discovered some dermal plates of Bothriolepis in a sandstone conformably overlying the Tientzulin limestone bearing Tentico-spirifer tenticulum, Camarotoechia hsikuangshanensis, C. hunanensis in N Kwangtung. He shows again some doubt on the early Eifelian age

关键词： limestone sandstone bedded Silurian shale dermal doubt abundant writer Eastern

NUTRITIONFORCHILdANdAdOLESCENTATHLETES

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

中国运动医学杂志 2000年第4期19卷 443-447页

作者： Oded Bar-Or M.d. Children’s Exercise & Nutrition Centre Mc Master University Hamilton Ontario Canada

面向工业互联网的社群化制造模式及3d打印测试床研发

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

中国科学：技术科学 2022年第1期52卷 88-103页

作者：江平宇史皓良杨茂林郭威 MAKANdA Inno Lorren désir 董华伟西安交通大学机械制造系统工程国家重点实验室西安710049

新一代信息技术与制造业的深度融合正推动着制造业向社会化、服务化、互联集成化与平台化发展,面向工业互联网的社群化制造模式契合了当前制造业在智能化转型升级和创建新业态上的愿景.据此,本文在对当前制造模式演变分析的基础上给出... 详细信息

新一代信息技术与制造业的深度融合正推动着制造业向社会化、服务化、互联集成化与平台化发展,面向工业互联网的社群化制造模式契合了当前制造业在智能化转型升级和创建新业态上的愿景.据此,本文在对当前制造模式演变分析的基础上给出了信息-物理-社交互联驱动的社群化制造模式体系架构和运行逻辑,进一步探讨了社交传感器驱动的社群化资源聚类与社区/社群创成、信息-物理-社交互联驱动的社群化制造系统和社群化制造软件模型三项关键实现技术.研发了面向社群化制造模式的3d打印测试床,并通过测试床的应用开发和生产运行流程的介绍,验证了社群化制造理论的可行性,同时也为工业互联网产业应用实践提供示范导向作用.

关键词：制造模式工业互联网社群化制造信息-物理-社交互联 3d打印测试床

An examination of the population dynamics of syngnathid fishes within Tampa Bay,Florida,USA

在线全文

学校读者我要写书评

暂无评论

Current Zoology 2010年第1期56卷 118-133页

作者： Heather d.MASONJONES Emily ROSE Lori Benson McRAE danielle L.dIXSON Biology department University of Tampa Biology department Texas A & M University School of Marine and Tropical Biology James Cook University

Seagrass ecosystems worldwide have been declining, leading to a decrease in associated fish populations, especially those with low mobility such as syngnathids （pipefish and seahorses）. This two-year pilot study investigated seasonal patterns in density, growth, site fidelity, and population dynamics of Tampa Bay （FL） syngnathid fishes at a site adjacent to two marinas under construction. Using a modified mark-recapture technique, fish were collected periodically from three closely located sites that varied in seagrass species （Thalassia spp., Syringodium spp., and mixed-grass sites） and their distance from open water, but had consistent physical/chemical environmental characteristics. Fish were marked, photographed for body size and gender measurements, and released the same day at the capture site. Of the 5695 individuals surveyed, 49 individuals were recaptured, indicating a large, flexible population. Population density peaks were observed in July of both years, with low densities in late winter and late summer. Spatially, syngnathid densities were highest closest to the mouth of the bay and lowest near the shoreline. Seven species of syngnathid fishes were observed, and species-specific patterns of seagrass use emerged during the study. However, only two species, Syngnathus scovelli and Hippoeampus zosterae, were observed at high frequencies. For these two species, body size decreased across the study period, but while S. scovelli＇s population density decreased, H. zosterae＇s increased. Across six of the seven species, population size declined over the course of this preliminary study; however, seasonal shifts were impossible to distinguish from potential anthropogenic effects of construction [Current Zoology 56 （1）： 118-133, 2010].

关键词： Syngnathids Habitat-use Seahorse Pipefish Population density Mark-recapture

An efficient synthesis of some new 3-bipyridinyl substituted coumarins as potent antimicrobial agents

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2013年第3期24卷 227-229页

作者： Hemali B.Lad Rakesh R.Giri d.I.Brahmbhatt department of Chemistry Sardar Patel University

As a part of the ongoing studies in developing new antimicrobials, a series of structurally novel 3- bipyridinyl substituted coumarin derivatives 4a-f and Sa-f were synthesized by a single-step reaction protocol under Krohnke＇s reaction conditions. ]H NMR, 13C NMR, IR and mass spectral techniques were employed for the structural elucidation of the synthesized compounds. An evaluation of antimicrobial activity showed that almost all compounds exhibited better results than the referenced drugs. Among the synthesized derivatives 4f, $a and Sd were found to be the most potent analogs. Thus they could be promising lead for novel drugs.

关键词： Antimicrobial activityBipyridinyl coumarinsCoumarinsKrohnke's reaction

Improved Pinning Center Morphology in HTS with Order-of-Magnitude Increase in J_c and B_pin Compared to Columnar Pinning

在线全文

学校读者我要写书评

暂无评论

Tsinghua Science and Technology 2003年第3期8卷 266-279页

作者： R.weinstein A.Gandini R.Sawh d.Parks Beam Particle dynamics Laboratory Physics Departmentand Texas Center for Superconductivity and Advanced MaterialsUniversity of HoustonHoustonTexas 77204-5005USA

The motivation for continuous columnar pinning centers has been to provide maximum Upin. It has been assumed that this provides the best Jc and Bpin. Limitations on Jc and Spin observed for columnar pinning have been attributed to degradation of the order parameter and Tc. we examine columnar pinning by ionic damage and conclude instead that geometrical effects of columnar pinning on percolation path and on the number of pinning centers are the dominant limitations of columnar pinning, leading to a limit of Bpin- 4 T. Evidence suggests that multiple-in-line-defects (MILd) are far better suited to increase Jc and Bpin. The morphology of MILd pinning is reviewed. Ion energy loss per unit distance, Se, is found to be most promising in a regime almost diametrically opposite to that sought to maximize Upin. we expect Jc - 106 A/cm2 and Bpin > 40T from MILd pinning, despite sharply decreased Upin. Experimental confirmation is proposed.

关键词： improved pinning high critical current high field pinning ionic pinning centers columnar pinning limits

在线全文

学校读者我要写书评

暂无评论

高阻力吸气肌力量训练与运动耐量

中国康复 2024年第10期 624-624页

作者：龚秋文 Craighead d

高阻力吸气肌力量训练(IMST)是一种低容量、时间效率高的强化呼吸运动，可提高呼吸肌力。这项研究旨在确定IMST是否能改善中老年人的心肺健康、运动耐量和身体功能。这项双盲、随机、假对照、平行组设计试验包括50～79岁的健康男性和绝...

高阻力吸气肌力量训练(IMST)是一种低容量、时间效率高的强化呼吸运动，可提高呼吸肌力。这项研究旨在确定IMST是否能改善中老年人的心肺健康、运动耐量和身体功能。这项双盲、随机、假对照、平行组设计试验包括50～79岁的健康男性和绝经后女性。受试者被随机分配进行高阻力IMST或低阻力假训练。所有受试者每天进行30次吸气动作(6次呼吸/组，共5组，每组之间休息1min),每周6d, 持续6周。

关键词：

Investigations on landmine detection by BF_3 detector

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2007年第4期18卷 237-241页

作者： d.Rezaei OCHBELAGH H.Miri HAKIMABAd R.Izadi NAJAFABAdI department of Physics University of Mohaghegh ArdabilyP.O. Box 179ArdebilIran Physics department Faculty of SciencesFerdowsi University of MashhadMashhadIran

Experiments were carried out to investigate the possible use of neutron backscattering for the detection of polyethylene (PE) sample buried in the soil. In detection of landmine by neutrons, the neutron detector and its shield play an important role. In this paper, the effects of graphite, heavy water, polyethylene and boric acid moderators on the flux of back scattered neutrons were investigated. we have also experimentally verified the effect of BF3 detector shield and obtained good agreement with theory.

关键词：地雷中子源中子反散射 BF3装置重水

Early Paleozoic whole-rock Ce anomalies and secular eustatic changes in the Upper Yangtze region

在线全文

学校读者我要写书评

暂无评论

Science China Earth Sciences 2000年第3期43卷 328-336页

作者：冯洪真 B.-d.Erdtmann 王海峰 State Key Laboratory for Research of Mineral deposits Nanjing University Nanjing 210093 China Institut fur Angewandte Geowissenschaften II Technologische Universitat Berlin 10587 Deutschland Institute of Geology and Paleontology Chinese Academy of Sciences Nanjing 210093 China

The 65 whole-rock REE samples studied come from the classic sections of Early Cambrian to Early Silurian in the Yichang area, Hubei Province. REE concentrations tested on ICP-AES are normalized to the North American Shale Composite (NASC), and Ce anomaly values are calculated based on log[3Cen(2Lan+Ndn)]. with the whole-rock Ce anomaly used as a quantitative index of sea-level changes, 5 prominent eustatic circles are recognized, and a good corresponding relationship is observed between the black shale episodes and the transgressive events. On account of the global distributions of coeval black shales and the specified paleogeographic background of South China, a genetic hypothesis based on the model of O2-minimum zone expansion is suggested for the Early Paleozoic multi-episode black shales in South China.

关键词： whole-rock Ce anomalies eustatic circles geneses of black shales.