检索结果-南通市图书馆

Microstructural evolution of a recycled aluminum alloy deformed by equal channel angular pressing process

International Journal of Minerals,Metallurgy and Materials 2012年第11期19卷 1016-1022页

作者： Thabet Makhlouf Atef Rebhi Jean-Philippe Couzinié yannick champion Nabil Njah Applied Metallurgy Laboratory Faculty of SciencesUniversity of SfaxBP.1171 (3000) Sfax Institut de Chimie et des Matériaux Paris-Est (ICMPE) CNRS 2-8 rue Henri Dunant 94320 Thiais

The microstructural evolution of a recycled aluminum alloy after equal channel angular pressing （ECAP） up to four passes was investigated using X-ray diffxaction （XRD） analysis and transmission electron microscopy （TEM）. Microhardness tests were performed to determine the associated changes in mechanical properties. An ultrafine-grained material has been obtained with a microstructure showing a mixture of highly strained crystallites. A high density of dislocations was achieved as a result of severe plastic deformation （SPD） through the die. Changes in mechanical behavior are also revealed after ECAP due to strain hardening. Thermal analysis and TEM micrographs ob- tained after annealing indicate the succession of the recovery, recrystallization, and grain growth phenomena. Moreover, the energy stored during ECAP may be related to the dislocation density introduced by SPD. We finally emphasize the role played by the precipitates in this alloy.

关键词： aluminum alloys equal channel angular pressing (ECAP) microstructural evolution precipitates

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

Structure of nanocrystalline WC-10%Co powder

引用

中国有色金属学会会刊：英文版 2001年第4期11卷 529-534页

作者：杨志民毛昌辉杜军 Michel Daniel champion yannick Hagège Serge Htch Martin General Research Institute for Nonferrous Metals Centre d'Etudes de Chimie Métallurgique/CNRS 94407 Vitry-sur-Seine France

Nanostructured WC Co powders obtained by mechanical milling were investigated by combination of X ray diffraction (XRD) and high resolution transmission electron microscopy (HRTEM) techniques. Rietveld analysis indicates that the experimental XRD patterns cannot be satisfactorily explained with the hexagonal WC structure. HRTEM image analysis shows that in the as milled nanostructured powder, many WC grains contain stacking faults lying on the plane {10·0}. Analysis of phase images show that these defects are nearly periodically ordered along the direction. Based on these observations, a structural model was proposed for the WC grains with ordered stacking faults, which is in fact equivalent to a superstructure of WC with space group Amm2. When this model describing the faulted fraction of WC is introduced together with the normal WC structure (space group P6-m2) into the Rietveld refinement, a much better agreement between the calculated and experimental XRD profiles was obtained. This study allows to obtain the lattice parameters, grain size, microstrain and other structural information on the as milled powders.

关键词： structural properties mechanical milling WC Co

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

Dobutamine Infusion and Absence of Pulmonary Hypertension Are Associated with Decreased Mortality in a Cohort of 249 Patients with Cardiogenic Shock

引用

Health 2014年第18期6卷 2408-2415页

作者： Sébastien champion Bernard A. Gaüzère David Vandroux Bruno J. Bouchet Didier Drouet yannick Lefort Réanimation Polyvalente CHU de la Réunion H&ocirc pital Félix Guyon Saint Denis France

Objective: Prognostic analysis of 249 patients admitted for cardiogenic shock (CS) of various origins. Background: Little is known about prognosis of CS from non-ischemic cardiomyopathy. Methods: Retrospective monocentric study of patients referred to an ICU during 2 years. Results: Despite aggressive management including intra-aortic balloon pump (31%), extra-renal replacement therapy (36%), extra-corporeal life support (8%), and catecholamine infusion (97%), in-hospital mortality was 46%. Toxic CS or CS related to deficiency carried a better outcome (mortality 5%). Post-myocardial infarction or post-cardiac arrest CS was associated with higher mortality. In the multivariate analyses, only SAPS II (OR 1.037;1.013 - 1.056;p = 0.0001), pulmonary hypertension (OR 4.8;1.3 - 17;p = 0.02), extra-renal replacement therapy (OR 2.9;1.3 - 6;p = 0.006), and dobutamine infusion (OR 0.44;0.2 - 0.96;p = 0.04) were significantly associated with in-hospital mortality. Conclusion: Dobutamine infusion was associated with a better outcome. Higher SAPS II, pulmonary hypertension, and extra-renal replacement therapy were associated with increased in-hospital mortality.

关键词： Cardiogenic Shock Myocardial Infarction Catecholamine Pulmonary Hypertension Dobutamine Critically Ill

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

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

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：