检索结果-南通市图书馆

Microstructures in a carburized steel after isothermal pearlitic treatment

journal of Materials Science & Technology 2023年第29期160卷 66-75页

作者： j.abraham mathews H.Farahani j.Sietsma R.H.Petrov M.G.Mecozzi M.j.Santofimia Department of Materials Science and Engineering Delft University of TechnologyMekelweg 22628 CDDelftThe Netherlands Tata Steel Research&Development IJmuidenThe Netherlands Department of Electromechanical Systems and Metal EngineeringGhent UniversityTech Lane Ghent Science park-Campus A ZwijnaardeTechnologiepark 46Belgium

The influence of carbon concentration variations on pearlite formation(20 h at 600℃)in a case-carburized steel is *** resultant microstructure shows three distinct regions:carburized case,a transition region,and the original *** microstructural transition from the case to the core regions is observed to be relatively *** investigated region of the carburized case(0.9 wt.%C)con-tains two types of pearlite:ferrite+cementite and ferrite+M_(23)C_(6),where the pearlitic aggregate with M_(23)C_(6)shows faster formation *** kinetics of pearlite formation in the transition region(0.3 wt.%C)is very slow and is observed with only M_(23)C_(6)*** around 40%austenite decomposes into pearlite in the transition region,which,in comparison to the carburized case region of 0.9 wt.%C is a fraction that is lower by a factor of *** is absent in the investigated core region(0.16 wt.%C).The microstructure in this region is predominantly martensite and pro-eutectoid ferrite,with a fraction of ferrite well below the equilibrium *** formation in this region is limited by the redistribution of mainly Ni,Mn,and Cr,and their resulting solute drag effect on the austenite/ferrite interface.A ther-modynamic and kinetic argumentation of these observations is provided with the help of thermodynamic data,precipitation simulations,and a general mixed-mode Gibbs energy balance model.

关键词： Pearlite formation Carburized steel M 2_(3)C_(6)carbide Kinetics Solute drag

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

Is there a weekend effect in hip fracture patients presenting to a United Kingdom teaching hospital?

引用

World journal of Orthopedics 2016年第10期7卷 678-686页

作者： john abraham mathews Madhavi Vindlacheruvu Vikas Khanduja Department of Orthopaedics Addenbrooke’s Hospital

AIM To compare mortality and time-to-surgery of patients admitted with hip fracture to our teaching hospital on weekdays vs weekends. METHODS Data was prospectively collected and retrospectively analysed for 816 hip fracture patients. Multivariate logistic regression was carried out on 3 binary outcomes(timeto-surgery < 36 h; 30-d mortality; 120-d mortality), using the explanatory variables time-of-admission; age; gender; American Society of Anesthesiologist(ASA) grade; abbreviated mental test score(AMTS); fracture type; accommodation admitted from; walking ability outdoors; accompaniment outdoors and season. RESULTS Baseline characteristics were not statistically different between those admitted on weekdays vs weekends. Weekend admission was not associated with an increased time-to-surgery(P = 0.975), 30-d mortality(P = 0.842) or 120-d mortality(P = 0.425). Gender(P = 0.028), ASA grade(P < 0.001), AMTS(P = 0.041) and accompaniment outdoors(P = 0.033) were significant covariates for 30-d mortality. Furthermore, age(P < 0.001),gender(P = 0.011), ASA grade(P < 0.001), AMTS(P < 0.001) and accompaniment outdoors(P = 0.033) all significantly influenced mortality at 120 d. ASA(P < 0.001) and season(P = 0.014) had significant effect on the odds of undergoing surgery in under 36 *** Weekend admission was not associated with increased time-to-surgery or mortality in hip fracture patients. Demographic factors affect mortality in accordance with previous published reports.

关键词： Weekend Hip Fracture Mortality Season

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

Evaluating the impact of auxiliary fan practices on localised subsurface ventilation

引用

International journal of Mining Science and Technology 2019年第6期29卷 933-941页

作者： David j.de Villiers Marc j.mathews Philip Maré Marius Kleingeld Deon Arndt Centre for Research and Continued Engineering Development North-West University

Mines are continually expanding in size and depth,leading to an increased reliance on localised subsurface ventilation *** use of underground auxiliary fans is a favoured method to increase and control airflow in working ***,the effectiveness of auxiliary fans in this regard is not *** paper evaluated the performance of these underground fan systems in four different South African deeplevel gold mines.A total auxiliary fan system efficiency of 5%was found across six systems,with the average fan efficiency of 33 fans at 38%.The results showed that these fans deviate significantly from their design operating ***,there are significant shortcomings in current underground fan *** detailed investigations led to the conclusion that the assemblage of underground auxiliary fan systems results in significant energy ***,maintaining good underground fan practice such as optimal fan selection,ducting design and maintenance is crucial for the efficacy of a mine ventilation network.

关键词： Mine ventilation Underground fan assemblage Fan system performance

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

Corneal collagen crosslinking in patients treated with dextran versus isotonic hydroxypropyl methylcellulose (HPMC) riboflavin solution: a retrospective analysis

引用

Eye and Vision 2018年第1期5卷 211-216页

作者： Patrick B.Rapuano Priya M.mathews George j.Florakis Stephen L.Trokel Leejee H.Suh Department of Ophthalmology Edward S.Harkness Eye InstituteColumbia College of Physicians and Surgeons635 West 165th StreetNew YorkNY 10032USA

Background:Corneal collagen crosslinking(CXL)is a widely used treatment for halting the progression of *** initial studies of CXL were performed with a riboflavin solution containing dextran,recent protocols for CXL have indicated the use of a riboflavin solution containing isotonic hydroxypropyl methylcellulose(HPMC).This study was performed to investigate differences in visual outcomes and Scheimpflug(Pentacam)analysis in patients who have undergone epithelium-off CXL with riboflavin solution containing either 20%dextran versus 1.1%***:All patients in this non-randomized,non-masked,retrospective cohort analysis were treated at Edward *** Eye Institute,Columbia University Medical Center,New York,NY,***-seven eyes of 33 patients were crosslinked with a dextran solution and 19 eyes of 19 patients crosslinked with an isotonic HPMC solution,both using an epithelium-off 30-min,3 mW/cm2 *** patients had a diagnosis of keratoconus or postrefractive surgery *** spectacle corrected visual acuity(BSCVA)and Pentacam parameters were compared at all follow up visits(1,6,12,and 24 months).Differences between groups treated with HPMC and dextran were compared using student’s *** between treated eye and fellow eye were calculated and compared between HPMC and dextran groups using paired ***:Patients treated with a dextran solution had significantly greater improvement in BSCVA at 1,6,and 24 months(p<0.05)compared to the isotonic HPMC-treated *** increased in both groups at 1 month;however,HPMC-treated patients had a greater increase compared to dextran-treated patients(p=0.01).Kmax decreased in both groups at 6 and 12 months,although this finding was only significant in the HPMC-treated group at 12 ***:Our data suggest that crosslinking with the dextran solution may result in significantly better visual outcomes(demonstrated by visual acuity)compared to the isotonic HPMC ribof

关键词： Corneal crosslinking Isotonic HPMC Dextran

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

U.S. red meat production from foreign-born animals

引用

Agricultural Sciences 2012年第2期3卷 201-207页

作者： Michael j. McConnell Kenneth H. mathews jr. Rachel j. johnson Keithly jones US Department of Agriculture Economic Research Service Washington DC USA.

The North American Free Trade Agreement (NAFTA) propelled the integration of livestock markets among the United States, Mexico, and Canada. Along with vertical integration within the respective industries, different sectors of the cattle and hog industries have shifted their production locations based on resource efficiencies. Imports of live cattle and hogs, as well as beef and pork, in the United States have been steadily increasing since the implementation of NAFTA, except during the restrictions on cattle and beef imports from Canada due to bovine spongiform encephalopathy (bse) discoveries there in 2003. There are limited empirical sources that relate the importation of livestock to the domestic U.S. production of meats. This paper introduces a methodology to estimate the amount of U.S. beef and pork production that can be attributed to foreign-born cattle and hogs. The procedure uses official U.S. trade data to quantify livestock imported at various weights and stages of production and projects the final production date and weight using existing data and literature.

关键词： Beef Livestock Pork Trade

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

Deep data analytics for genetic engineering of diatoms linking genotype to phenotype via machine learning

引用

npj Computational Materials 2019年第1期5卷 580-587页

作者： Artem A.Trofimov Alison A.Pawlicki Nikolay Borodinov Shovon Mandal Teresa j.mathews Mark Hildebrand Maxim A.Ziatdinov Katherine A.Hausladen Paulina K.Urbanowicz Chad A.Steed Anton V.Ievlev Alex Belianinov joshua K.Michener Rama Vasudevan Olga S.Ovchinnikova Center for Nanophase Materials Sciences Oak Ridge National LaboratoryOak RidgeTN 37831USA Environmental Sciences Division Oak Ridge National LaboratoryOak RidgeTN 37830USA Scripps Institute of Oceanography University of CaliforniaSan DiegoLa JollaCA 92093USA Computer Science and Mathematics Division Oak Ridge National LaboratoryOak RidgeTN 37830USA Biosciences Division Oak Ridge National LaboratoryOak RidgeTN 37830USA

Genome engineering for materials synthesis is a promising avenue for manufacturing materials with unique properties under ambient *** in diatoms,unicellular algae that use silica to construct micron-scale cell walls with nanoscale features,is an attractive candidate for functional synthesis of materials for applications including photonics,sensing,filtration,and drug ***,controllably modifying diatom structure through targeted genetic modifications for these applications is a very promising *** this work,we used gene knockdown in Thalassiosira pseudonana diatoms to create modified strains with changes to structural morphology and linked genotype to phenotype using supervised machine *** artificial neural network(NN)was developed to distinguish wild and modified diatoms based on the SEM images of frustules exhibiting phenotypic changes caused by a specific protein(Thaps3_21880),resulting in 94% detection *** activation maps visualized physical changes that allowed the NNs to separate diatom strains,subsequently establishing a specific gene that controls pores.A further NN was created to batch process image data,automatically recognize pores,and extract pore-related *** interrelationship of the extracted paraments was visualized using a multivariate data visualization tool,called CrossVis,and allowed to directly link changes in morphological diatom phenotype of pore size and distribution with changes in the genotype.

关键词： pores walls linking

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

纺织品漂白的新途径

引用

国外纺织技术 2000年第3期 23-24页

作者： j.mathews 肖敏陈水林

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

纺织品漂白的新途径

引用

国外纺织技术（纺织针织服装化纤染整） 2000年第3期 23-24页

作者： j.mathews 肖敏陈水林

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

应用于射频领域的系统级封装(SIP):设计加工与产品实例

引用

中国集成电路 2005年第3期14卷 57-67页

作者： Dauglas j.mathews Michael P.Gaynor 为民安靠公司

无线电话手机,便携式电脑,数码照相机,以及它们与PDA等电子产品在各种各样的消费类产品和商用产品中的融合,推动了各种无线电互连系统的发展,并且要求这些互连系统(WLAN,PAN等)体积小,重量轻,能在集成的环境下工作。同时为了不断扩大市... 详细信息

无线电话手机,便携式电脑,数码照相机,以及它们与PDA等电子产品在各种各样的消费类产品和商用产品中的融合,推动了各种无线电互连系统的发展,并且要求这些互连系统(WLAN,PAN等)体积小,重量轻,能在集成的环境下工作。同时为了不断扩大市场规模,要求在缩小体积,减轻重量的同时,还能够不断地降低成本。总而言之,客户对于系统的要求就是不断扩大系统功能,降低成本。在这种强烈的市场驱动下,新出现的SIP封装逐步发展成为封装领域内强有力的竞争者。本文试图将RF系统的要求和封装的要求结合起来,考虑如何进行SIP的设计。集成化的RF系统,是将包括嵌入有滤波器,屏蔽器,甚至天线的衬底等等,都集成在一个传统意义上的半导体封装内。文章最后,举例介绍射频功率放大器(RFPA),滤波器,蓝牙,以及WLAN等电子系统的具体解决方案。

关键词： SIP封装系统级封装 WLAN 重量轻滤波器射频功率放大器无线电话产品降低成本扩大

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

开发适合女性需求的小额保险产品

引用

经营与管理 2010年第10期 18-20页

作者：钱勤华 Anjali Banthia Susan johnson Michael j.McCord Brandon mathews 石家庄邮电职业技术学院金融系

在世界贫困人口中,女性占70%。与男性相比,她们不仅收入低,对财产的所有权和支配权小,而且因生理结构的特殊性,有许多弱点,还要面对暴力威胁。当这些弱点关系到家庭利益和家庭安全时,女性对风险管理最佳方式的需求就变得十分强烈。保险... 详细信息

在世界贫困人口中,女性占70%。与男性相比,她们不仅收入低,对财产的所有权和支配权小,而且因生理结构的特殊性,有许多弱点,还要面对暴力威胁。当这些弱点关系到家庭利益和家庭安全时,女性对风险管理最佳方式的需求就变得十分强烈。保险的功能就在于管理风险和降低

关键词：小额保险敏感度需求保单女性险种

来源：博看期刊

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

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：