检索结果-南通市图书馆

Laser additive manufactured high-performance Fe-based composites with unique strengthening structure

Journal of Materials Science & Technology 2021年第30期89卷 242-252页

作者： Hongyu Chen Dongdong Gu Liang Deng Tiwen Lu uta.Kühn Konrad Kosiba College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016China Jiangsu Provincial Engineering Laboratory for Laser Additive Manufacturing of High-Performance Metallic Components Nanjing University of Aeronautics and AstronauticsNanjing 210016China Leibniz IFW Dresden Institute for Complex MaterialsP.O.Box 270116D-01069 DresdenGermany

Steel matrix composites(SMCs),reinforced by ceramic particles,have received a consistent attention in recent *** conventional methods to prepare SMCs is generally challenging,and the mechanical properties of conventionally fabricated SMCs are *** this study,we successfully fabricated highperformance SMCs by laser powder bed fusion(LPBF)of a composite powder consisting of Fe-based alloy powder and submicron-sized WC *** effect of laser energy density on the phase formation,microstructural evolution,overall density and resulting mechanical properties of LPBF-fabricated composites was *** present results show that a novel Fe_(2)W_(4)C carbidic network precipitates in the solidified microstructure entailing segregations along the boundaries of cellular *** presence of this carbidic network hampers the growth of sub-grains even at elevated temperatures,and hence,stabilizes the grain size though prepared at a broad range of different energy *** exact distribution of the Fe_(2)W_(4)C carbides depends on the employed laser energy densities,as for instance they are more uniformly distributed at higher energy *** density of LPBF samples reaches the maximum value of 99.4%at 150 J/mm^(3).In this parameter set,high microhardness of~753 HV,compression strength of~3350 MPa and fracture strain of~24.4%are *** enhanced mechanical properties are ascribed to less metallurgical defects,higher volume fraction of the martensitic phase and increasing pile-up dislocations resulting from the pinning effect by Fe_(2)W_(4)C carbide.

关键词： Laser additive manufacturing Laser powder bed fusion Steel matrix composite Microstructures Mechanical properties

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Achieving exceptional wear resistance in a crack-free high-carbon tool steel fabricated by laser powder bed fusion without pre-heating

引用

Journal of Materials Science & Technology 2023年第25期156卷 1-19页

作者： Konrad Kosiba Daniel Wolf Matthias Bönisch Kai Neufeld Ruben Hühne Tobias Gustmann Jozef Bednarčík Hongyu Chen Xiaoliang Han Volker Hoffmann Lukas Beyer uta.Kühn Sergio Scudino Lars Giebeler Julia K.Hufenbach Leibniz Institute for Solid State and Materials Research (IFW) Dresden E.V. Helmholtzstr. 20Dresden 01069Germany Department of Materials Engineering KU LeuvenKasteelpark Arenberg 44bus 2450Leuven 3001Belgium Department of Condensed Matter Physics Institute of PhysicsP.J. Safarik University in KosicePark Angelinum 9Kosice 04154Slovakia Institute of Experimental Physics Slovak Academy of ScienceWatsonova 47Kosice 040 01Slovakia Key Laboratory of Impact and Safety Engineering of Ministry of Education of China Ningbo UniversityNingbo 315211China TU Bergakademie Freiberg Institute of Materials ScienceGustav-Zeuner-Str. 5Freiberg 09599Germany

Laser powder bed fusion(LPBF)for the fabrication of dense components used for tooling applications,is highly *** stresses,which evolve in the additively manufactured part,are inherent to LPBF *** additional stress contribution in high-carbon steels arises from the austenite-to-martensite phase transformation,which may eventually lead to cracking or even *** an alternative to pre-heating the base plate,which is not striven by industry,lowering the martensite content which forms in the part,is essential for the fabrication of dense parts by LPBF of high-carbon tool steels which are then adapted to *** this study,a successful strategy demonstrates the processing of the Fe85Cr4Mo1V1W8C1(wt%)high-carbon steel by LPBF into dense parts(99.8%).The hierarchical microstructure consists of austenitic and martensitic grains separated by elemental segregations in which nanoscopic carbide particles form a network.A high density of microsegregation was observed at the molten pool boundary ultimately forming a *** LPBF-fabricated steel shows a yield strength,ultimate compressive stress,and total strain of 1210 MPa,3556 MPa,and 27.4%,*** mechanical and wear performance is rated against the industrially employed and highly wear-resistant 1.2379 tool steel taken as the *** its lower macro-hardness,the LPBF steel(58.6 HRC,0.0061 mm^(3) Nm^(-1))shows a higher wear resistance than the reference steel(62.6 HRC,0.0078 mm^(3) Nm^(-1)).This behavior results from the wear-induced formation of martensite in a microscale thick layer directly at the worn surface,as it was proven via high-energy X-ray diffraction mapping.

关键词： Additive manufacturing Laser powder bed fusion Steel Wear TRIP

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Plant diversity and community history shift colonization success from early- to mid-successional species

引用

Journal of Plant Ecology 2015年第3期8卷 231-241页

作者： Christiane Roscher uta.Gerighausen Bernhard Schmid Ernst-Detlef Schulze UFZ Helmholtz Centre for Environmental ResearchDepartment of Community EcologyTheodor-Lieser-Strasse 4D-06120 HalleGermany Max Planck Institute for Biogeochemistry PO Box 100164D-07701 JenaGermany Institute of Evolutionary Biology and Environmental Studies and Zurich-Basel Plant Science Center University of ZurichWinterthurerstrasse 1908057 ZurichSwitzerland

Aims Functional traits are supposed to play an important role in deter-mining the colonization success of new species into established ***-term experimental studies have documented higher resistance of more diverse grasslands against coloni-zation by new ***,little is known about which traits colonizers should have to successfully invade diverse plant communities in the longer term and how community his-tory may modify the resistance of diverse communities against *** In a grassland biodiversity experiment(Jena Experiment)established with different species richness(s;1,2,4,8 and 16)and functional group(Fg)number and composition(1 to 4;legumes,grasses,small herbs,tall herbs),we studied colonization of naturally dispersed species in split-plots(i)with different duration of weeding(never weeded,weeded for 3 or 6 years and then un-weeded for 1 year)and(ii)with different duration of colonization(7 years,4 years and 1 year after cessation of weeding).Important Findingsresistance against colonization by new species declined with increased duration of weeding(on average 13,17 and 22 col-onizer species in 1-,4-and 7-year-old communities,respec-tively).Communities established at low diversity accumulated more colonizer species with a longer duration of weeding than more diverse *** of colonization had only small effects on the number of colonizer *** with early successional traits,*** life cycle,reproduction by seeds,small seeds,long-lived seeds and an earlier start of a longer flowering period,were favoured in species-poor newly established experimental plant communities(short duration of weeding)and early after cessation of weeding(short duration of colonization).a change from early-to mid-successional traits,*** growth,perennial life cycle,vegetative reproduction,characterized colonization at increased plant diversity and in communities with legumes or without *** absence/gr

关键词： abundance-weighted community mean traits biodiversity colonization simple community mean traits species richness

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Studienweg deutsch. Horen und sprechen, 听说训练. 2

引用

2006年

作者： uta.Ettel

来源：畅想之星图书光盘版（南... 评论

在线全文

畅想之星图书光盘版（南通市图书馆镜像）

学校读者我要写书评

暂无评论

Genetic diversity for mycorrhizal symbiosis and phosphate transporters in rice

引用

Journal of Integrative Plant Biology 2015年第11期57卷 969-979页

作者： Kwanho Jeong Nicolas Mattes Sheryl Catausan Joong Hyoun Chin uta.Paszkowski Sigrid Heuer Southern Cross Plant Science Southern Cross University International Rice Research Institute(IRRI) Crop and Environmental Sciences Division Seoul National University College of Agriculture and Life SciencesPlant Genomics and Breeding Institute University of Cambridge Department of Plant Sciences Australian Center For Plant Functional Genomics(ACPFG)

Phosphorus （P） is a major plant nutrient and developing crops with higher P-use efficiency is an important breeding goal. In this context we have conducted a comparative study of irrigated and rainfed rice varieties to assess genotypic differences in colonization with arbuscular mycorrhizal （AM） fungi and expression of different P trans- porter genes. Plants were grown in three different soil samples from a rice farm in the Philippines. The data show that AM symbiosis in all varieties was established after 4 weeks of growth under aerobic conditions and that, in soil derived from a rice paddy, natural AM populations recovered within 6 weeks. The analysis of AM marker genes （AM1, AM3, AM14） and P transporter genes for the direct Pi uptake （PT2, PT6） and AM-mediated pathway （PTll, PT13） were largely in agreement with the observed root AM colonization providing a useful tool for diversity studies. Interestingly, delayed AM colonization was observed in the aus-type rice varieties which might be due to their different root structure and might confer an advantage for weed competition in the field. The data further showed that P-starvation induced root growth and expression of the high-affinity P transporter PT6 was highest in the irrigated variety IR66 which a]so maintained grain yield under P-deficient field conditions.

关键词： Mycorrhiza P deficiency tolerance phosphatetransporters rice roots

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Liver tumor infiltrating lymphocytes: Comparison of hepatocellular and cholangiolar carcinoma

引用

World Journal of Gastroenterology 2009年第40期15卷 5053-5057页

作者： Hans-Udo Kasper uta.Drebber Dirk Ludger Stippel Hans Peter Dienes Anton Gillessen Department of Pathology Medical CenterClemenshospital Münster Department of Pathology University of Cologne Department of Visceral and Vascular Surgery University of Cologne Department of Gastroenterology Herz-Jesu-Hospital Hiltrup

AIM: To investigate the role of tumor inf iltrating lym-phocytes (TIL) in primary hepatocellular and cholangio-lar carcinomas of the ***: Immunohistochemical analysis was per-formed including antibodies to CD3, CD4, CD8, CD20, CD56 and TIA-1 in formalin-f ixed and paraff in-embed-ded tissue of 35 liver resection specimens of hepatocel-lular or cholangiocellular carcinomas. Semiquantitative evaluation was performed with emphasis on the area of the tumor itself and of the tumor/liver ***: All hepatocellular carcinomas showed in-filtration of lymphocytes predominantly around the tumor in the tumor/liver interface consisting mainly of CD3+ CD4+ T lymphocytes [164.3/10 high power f ields (HPF)] and in the tumor itself of CD8+ cells (54.9/10 HPF). Cholangiocarcinomas contained a heterogeneous amount of TIL, composed mainly of CD3+ T cells with a predominance of CD8+ cells in the tumor tissue (52.6/10 HPF) and of CD4+ cells in the interface region (223.1/10 HPF). CD56+ cells of the innate immune system were scarce. There was no significant difference between hepatocellular or cholangiolar carcinoma. No correlation with the clinicopathological data was seen. CONCLUSION: Liver TIL consists of intratumoral CD8+ T cells and peritumoral CD4+ T cells indepen-dent of histogenetic origin. Different functions of lym-phocytes in these regions seem possible.

关键词：原发性肝癌 T淋巴细胞肿瘤浸润高通滤波器胆管肿瘤肿瘤组织半定量评价 CD8

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Trapping and Driving Individual Charged Micro-particles in Fluid with an Electrostatic Device

引用

Nano-Micro Letters 2016年第3期8卷 270-281页

作者： Jingjing Xu Zijing Lei Jingkun Guo Jie Huang Wei Wang uta.Reibetanz Shengyong Xu Key Laboratory for the Physics & Chemistry of Nanodevices and Department of Electronics Peking University Institute of Microelectronics Peking University Medical Faculty Institute for Medical Physics and Biophysics University of Leipzig

A variety of micro-tweezers techniques, such as optical tweezers, magnetic tweezers, and dielectrophoresis technique, have been applied intensively in precise characterization of micro/nanoparticles and bio-molecules. They have contributed remarkably in better understanding of working mechanisms of individual sub-cell organelles, proteins, and DNA. In this paper, we present a controllable electrostatic device embedded in a microchannel, which is capable of driving,trapping, and releasing charged micro-particles suspended in microfluid, demonstrating the basic concepts of electrostatic tweezers. Such a device is scalable to smaller size and offers an alternative to currently used micro-tweezers for application in sorting, selecting, manipulating, and analyzing individual micro/nanoparticles. Furthermore, the system offers the potential in being combined with dielectrophoresis and other techniques to create hybrid micro-manipulation systems.

关键词： Electrostatic tweezers Charged particles Coulomb potential well Manipulation Trap

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

CuZr-based bulk metallic glass and glass matrix composites fabricated by selective laser melting

引用

Journal of Materials Science & Technology 2021年第22期81卷 139-150页

作者： Liang Deng Long Zhang Konrad Kosiba RenéLimbach Lothar Wondraczek Gang Wang Dongdong Gu uta.Kühn Simon Pauly Leibniz IFW Dresden Institute for Complex MaterialsHelmholtzstraße 20D-01069DresdenGermany Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang110016China Otto Schott Institute of Materials Research University of JenaFraunhoferstraße 6D-07743 JenaGermany Laboratory for Microstructure Institute of MaterialsShanghai UniversityShanghai200444China College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing210016China University of Applied Sciences Aschaffenburg Würzburger Straße 45D-63743AschaffenburgGermany

Monolithic bulk metallic glass and glass matrix composites with a relative density above 98%were produced by processing Cu_(46)Zr_(46)Al_(8)(at.%)via selective laser melting(SLM).Their microstructures and mechanical properties were systematically examined.B2 CuZr nanocrystals(30-100 nm in diameter)are uniformly dispersed in the glassy matrix when SLM is conducted at an intermediate energy *** B2 CuZr nanocrystals nucleate the oxygen-stabilized big cube phase during a remelting *** presence of these nanocrystals increases the structural heterogeneity as indirectly revealed by mircrohardness and nanoindentation *** corresponding maps in combination with calorimetric data indicate that the glassy phase is altered by the processing *** the formation of crystals and a high overall free volume content,all additively manufactured samples fail at lower stress than the as-cast glass and without any plastic *** inherent brittleness is attributed to the presence of relatively large pores and the increased oxygen content after selective laser melting.

关键词： Selective laser melting CuZr-based glass Bulk metallic glass matrix composites Phase formation Mechanical properties

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Phase formation of a biocompatible Ti-based alloy under kinetic constraints studied via in-situ high-energy X-ray diffraction

引用

Progress in Natural Science:Materials International 2020年第3期30卷 432-436页

作者： Konrad Kosiba André Rothkirch Junhee Han Liang Deng Benjamin Escher Gang Wang uta.Kühn Jozef Bednarcik Leibniz IFW Dresden Institute for Complex Materials DESY Photon Science 3. Korea Institute of Industrial Technology (KITECH) Korea Institute for Rare Metals 4. Fraunhofer Institute for Photonic Microsystems IPMS Department of Engineering 5. Laboratory for Microstructures Institute of Materials Shanghai University 6. J. Safarik University in Kosice Institute of Physics Department of Condensed Matter Physics

The biocompatible Ti40Cu34Pd14Zr10Sn2bulk metallic glass was rapidly heated,also known as flash-annealed,at varying heating rates up to 1579 K/***,the phase formation was characterized via advanced in-situ highenergy X-ray *** has been found that the evolving kinetic constraints can be used as a tool to deliberately alter the crystalline phase *** novel processing route permits to select phases to crystallize to a predefined fraction and,thus,to potentially design the microstructure of materials according to a specified ***,flash-annealing poses a unique synthesis route to design materials with,for instance,good biomechanical compatibility.

关键词： High-energy X-ray diffraction Flash-annealing Phase formation Metallic glass Biocompatible Ti alloy

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Characterization of human gene encoding SLA/LP autoantigen and its conserved homologs in mouse,fish,fly,and worm

引用

World Journal of Gastroenterology 2006年第6期12卷 902-907页

作者： Chun-Xia Wang Andreas Teufel uta.Cheruti Joachim Groetzinger Peter R Galle Ansgar W Lohse Johannes Herkel I. Department of Medicine University Medical Centre Hamburg-Eppendorf Hamburg Germany Shandong University Shandong Provincial Hospital Jinan Shandong Province China I. Department ofMedicine Johannes Gutenberg University Mainz Germany Institute of Biochemistry Christian-Albretchts-University Kiel Germany

瞄准：来临逃犯 SLA/LP 分子的功能，我们在各种各样的种类描绘了 genomic 组织和遗传因子的主要的反和 SLA/LP 分子的功能的性质的保存。方法：借助于计算生物学，我们在人，老鼠，斑马鱼，苍蝇，和蠕虫描绘了完全的 SLA/LP 基因， mR... 详细信息

瞄准：来临逃犯 SLA/LP 分子的功能，我们在各种各样的种类描绘了 genomic 组织和遗传因子的主要的反和 SLA/LP 分子的功能的性质的保存。方法：借助于计算生物学，我们在人，老鼠，斑马鱼，苍蝇，和蠕虫描绘了完全的 SLA/LP 基因， mRNA 和推出的蛋白质序列。结果：约 39 kb 的人的 SLA/LP 基因顺序，印射到染色体 4p15.2，在 11 前 ons， 10 或 11 被翻译被组织，取决于 splice 变体。相应分子在几个生物模型有机体被识别。各种各样的相应蛋白质序列显示出类似或相同的高度，尤其是在功能的重要性的那些残余。与相应序列缺乏重要相同的人的蛋白质顺序的唯一的领域是遗传因子的 epitope 从自体免疫的肝炎(AIH ) 由自身抗体认出了的主要的反病人。结论：SLA/LP 分子和它的机能上地相关的残余高度在整个进化被保存了，建议分子的不可缺少的功能。发现那个唯一的非保存的领域是人的 SLA/LP 的遗传因子的 epitope 定序的主导的反，建议 SLA/LP 汽车免疫是驾驶 autoantigen 的而非被分子的模仿驾驶。

关键词：基因编码同系物老鼠鱼苍蝇生物信息学

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：