检索结果-南通市图书馆

Comparison of Design and Analysis of Concrete Gravity Dam

Natural Resources 2012年第1期3卷 18-28页

作者： md. Hazrat Ali M. R. Alam M. N. Haque M. j. Alam Department of Civil Engineering Chittagong University of Engineering & Technology Chittagong Bangladesh

Gravity dams are solid concrete structures that maintain their stability against design loads from the geometric shape, mass and strength of the concrete. The purposes of dam construction may include navigation, flood damage reduction, hydroelectric power generation, fish and wildlife enhancement, water quality, water supply, and recreation. The design and evaluation of concrete gravity dam for earthquake loading must be based on appropriate criteria that reflect both the desired level of safety and the choice of the design and evaluation procedures. In Bangladesh, the entire country is divided into 3 seismic zones, depending upon the severity of the earthquake intensity. Thus, the main aim of this study is to design high concrete gravity dams based on the U.S.B.R. recommendations in seismic zone II of Bangladesh, for varying horizontal earthquake intensities from 0.10 g - 0.30 g with 0.05 g increment to take into account the uncertainty and severity of earthquake intensities and constant other design loads, and to analyze its stability and stress conditions using analytical 2D gravity method and finite element method. The results of the horizontal earthquake intensity perturbation suggest that the stabilizing moments are found to decrease significantly with the increment of horizontal earthquake intensity while dealing with the U.S.B.R. recommended initial dam section, indicating endanger to the dam stability, thus larger dam section is provided to increase the stabilizing moments and to make it safe against failure. The vertical, principal and shear stresses obtained using ANSYS 5.4 analyses are compared with those obtained using 2D gravity method and found less compares to 2D gravity method, except the principal stresses at the toe of the gravity dam for 0.10 g - 0.15 g. Although, it seems apparently that smaller dam section may be sufficient for stress analyses using ANSYS 5.4, it would not be possible to achieve the required factors of safety with smaller dam s

关键词： Comparison Concrete Gravity Dam Dam Failure Design Earthquake Intensity Perturbation Stability and Stress

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

Multistage serrated flow behavior of a medium-manganese high-carbon steel

引用

j.urnal of Iron and Steel Research International 2020年第9期27卷 1064-1072页

作者： j.Chen Y.Zhang j.j.Wang C.M.Liu S.X.Zhao Key Laboratory for Anisotropy and Texture of Materials Ministry of EducationNortheastern UniversityShenyang 110819LiaoningChina Shenyang Industrial Transformation Upgrading Promotion Center Shenyang 110083LiaoningChina The State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819LiaoningChina School of Materials Science and Engineering Northeastern UniversityShenyang 110819LiaoningChina Central Research Institute Baoshan Iron&Steel Co.Ltd.Shanghai 201999China

The deformation mechanisms and the flow stress behavior of a medium-manganese high-carbon steel during cold deformation at a strain rate of 10×5 s^-1 were explored using a universal testing machine,an X-ray diffractometer,a field emission scanning electron microscope and a high-resolution transmission electron *** results show that continuous step-up serrated flow behavior appears after the yielding point,and the true stress-strain curve is roughly divided into five stages based on distinctive densities and amplitudes of *** strengthening mechanisms of the experimental steel involve Cottrell atmosphere,twinning-induced plasticity(TWIP)efect and transformation-induced plasticity(TRIP)*** effect is the dominant deformation mechanism,and deformation twins formed by TWIP effect comprise primary,secondary and ***,TRIP effect arises in the local high-strain *** element plays a key role in the transformation of the deformation mechanism.A small amount of carbide precipitates around twin boundaries lead to the formation of local carbon-poor regions,and md temperature and stacking fault energy of medium-manganese high-carbon steel are propitious to the occurrence of TRIP *** addition,the contributions of various deformation mechanisms to plasticity are calculated,and that of TWIP effect is the greatest.

关键词： Serrated flow Deformation mechanism Deformation twin Twinning-induced plasticity Transformation-induced plasticity

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

Methionine sources and genotype affect embryonic intestinal development,antioxidants,tight j.nctions,and growth-related gene expression in chickens

引用

Animal Nutrition 2024年第1期16卷 218-230页

作者： j.mes K.Lugata Sawadi F.Ndunguru Gebrehaweria K.Reda Xénia E.Ozsváth Eszter Angyal Levente Czeglédi Gabriella Gulyás Renáta Knop j.nos Oláh Zoltán Mészár Rita Varga Brigitta Csernus Csaba Szabó Department of Animal Nutrition and Physiology Faculty of Agriculture and Food Sciences and Environmental ManagementUniversity of DebrecenDebrecenHungary Department of Animal Husbandry Faculty of Agriculture and Food Sciences and Environmental ManagementUniversity of DebrecenDebrecenHungary Faculty of Agriculture and Food Sciences and Environmental Management Doctoral School of Animal ScienceUniversity of DebrecenDebrecenHungary Institutes for Agricultural Research and Educational Farm University of DebrecenDebrecenHungary Department of Anatomy Histology and EmbryologyFaculty of MedicineUniversity of DebrecenDebrecenHungary Department of Evolutionary Zoology and Human Biology Faculty of Science and TechnologyUniversity of DebrecenDebrecenHungary

Methionine(Met)is an essential and first limiting amino acid in the poultry diet that plays a significant role in chicken embryonic development and *** present study examined the effect of in ovo inj.ction of DL-Met and L-Met sources and genotypes on chicken embryonic-intestinal development and *** eggs of the two genotypes,TETRA-SL layer hybrid(TSL)—commercial layer hybrid and Hungarian Partridge colored hen breed(HPC)—a native genotype,were randomly distributed into four treatments for each *** treatment groups include the following:1)control non-inj.cted eggs(NoIn);2)saline-inj.cted(SaIn);3)DL-Met inj.cted(DLM);and 4)L-Met inj.cted(LM).The in ovo inj.ction was carried out on 17.5 d of embryonic development;after hatching,eight chicks per group were sacrificed,and the j.j.num was extracted for *** results showed that both DLM and LM groups had enhanced intestinal development as evidenced by increased villus width,villus height,and villus area(Pmd2),occludin(OCLN),superoxide dismutase 1(SOD1),and GST3 genes than the TSL genotype(Pj.ction of Met enhanced intestinal development,and function,with genotypes responding differently under normal *** also influenced the expression of intestinal antioxidants,tight j.nction,and growth-related genes.

关键词： DL-Methionine L-Methionine In ovo inj.ction Intestinal development Poultry

来源：

维普期刊数据库

同方期刊数据库

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

The Impact of the Acute Results on the Long-Term Outcome after the Treatment of In-stent Restenosis: A Serial Intravascular Ultrasound Study

引用

海南医学 2002年第11期13卷 66-67页

作者： WU Zhiyong,md, Taya L,McMillan, MPH,Gary S. Mintz, md, Akiko Maehara, md, Daniel Canos, MPH,WU Hongsheng, Ph.D, Ron Waksman, md, Neil j. Weissman, md The people’s Hospital of Hainan Province and Washington Hospital Center,Washington, DC, USA The people 's Hospital of Hainan Province and Washington Hospital Center Washington DC USA

Stenting reduces acute complications and restenosis compared to balloon angioplasty and other devices. However, in- stent restenosis (ISR) is an important clinical problem. The current serial intravascular ultrasound (IVUS)analysis was undertaken to determine whether the acute results obtained during the treatment of ISR influence the long term results and whether this is true for patients treated with and without adj.nct brachytherapy.

关键词：血管内超声检查血管再狭窄影像学表现

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

Optimal quantum well width and the effect of quantum well position on the performance of transistor lasers

引用

Optoelectronics Letters 2013年第1期9卷 18-20页

作者： md. Ahsan Habib Subrata Das Saeed Mahmud Ullah Shahida Rafique Department of Electronics and Communication Engineering University of Information Technology and Sciences Department of Applied Physics Electronics and Communication Engineering University of Dhaka

Transistor laser (TL) model based on InGaP/GaAs/InGaAs/GaAs is analyzed and presented. It is realized that quantum well (QW) with width of 10 nm may be formed for low base threshold current density j.th . The emission wavelength is found to be 1.05 μm, and the indium (In) composition is 0.25 for optimal QW width. It is identified that j.th decreases with the movement of QW towards the base-emitter (B-E) interface. Small signal optical response is calculated, and the effect of QW position is studied. The bandwidth is enhanced due to the movement of the QW towards the emitter base j.nction.

关键词：量子阱激光器晶体管宽度位置性能阈值电流密度发射波长

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

The Preliminary Study of Iron Deposition in the Brain in Patients with Parkinson's Disease using Susceptibility Weighted Imaging

The Preliminary Study of Iron Deposition in the Brain in Pat...

引用

中华医学会第16次全国放射学学术大会

作者： K Zhang md Beij.ng China K Li md C Yu j.Liu md PhD

PURPOSE To investigate the abnormal accumulation of iron in the brain in patients with Parkinson’s disease(PD). METHOD AND MATERIALS Susceptibility weighted imaging(SWI) was performed in 15 patients with PD and 15 age and sex-matched healthy *** subj.cts were enrolled after excluding other cerebral *** Signal Processing in NMR(SPIN) was employed to filter the original phase images to get the

关键词：

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

手术与麻醉：治愈躯体而损害大脑？

引用

麻醉与镇痛 2012年第3期8卷 1-3页

作者： Gregory Crosby, md Deborah j. Culley, md 安博(译) 杜金(校) the Harvard Medical School Department of Amesthesiology Perioperative and Pain Medicine Brigham and Women's Hospital Boston Massachusetts. 不详

从19世纪40年代手术麻醉出现，到20世纪90年代末，主流观点认为大脑不会因手术打击和全身麻醉药物引起的催眠而受损。从那时起到现在，大量科学研究文献提出的事实并非总是如此，有的时候，为了尽可能治疗躯体，我们可能已经损害了大脑... 详细信息

从19世纪40年代手术麻醉出现，到20世纪90年代末，主流观点认为大脑不会因手术打击和全身麻醉药物引起的催眠而受损。从那时起到现在，大量科学研究文献提出的事实并非总是如此，有的时候，为了尽可能治疗躯体，我们可能已经损害了大脑。但是，这种损害是什么时候开始的？为什么会出现？什么途径？这些问题仍被反复争论。而且，争论愈演愈烈，看上去短时间内似乎也难有答案。

关键词：麻醉药物大脑损害手术躯体治愈科学研究

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

Pancreatic cancer surgery with vascular resection: current concepts and perspectives

引用

j.urnal of Pancreatology 2019年第1期2卷 1-5页

作者： Artur Rebelo Christoph W.Michalski j.rg Ukkat j.rg Kleeff Department of Visceral Vascular and Endocrine SurgeryHalle University HospitalMartin-Luther-University Halle-WittenbergHalleGermany

Pancreatic cancer is a devastating disease and resection at an early disease stage is the best chance of cure. Less than 20% of all patients present with a resectable tumor, while another 20% to 30% have locally advanced pancreatic cancer and the maj.rity of the patient suffer from metastatic disease. Recently, it has been recognized that there is a 4th group of patients with so-called borderline resectable disease. Here, the tumor approaches or infiltrates the vascular axis (superior mesenteric vein/portal vein and/or superior mesenteric/hepatic artery/celiac trunk). While a large number of tumors with suspected venous infiltration can be resected with concomitant venous resection and reconstruction, arterial infiltration has been considered a contraindication to resection. Neoadj.vant treatment with combination chemotherapy protocols with or without radiotherapy has allowed for higher resection rates even in patients with arterial invasion. Here, we review the contemporary literature on extensive pancreatic cancer surgery with vascular resection and reconstruction.

关键词： Borderline pancreatic cancer Celiac artery Hepatic artery Neoadj.vant chemotherapy Pancreatic cancer Portal vein Superior mesenteric artery Superior mesenteric vein Vascular resection

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

反方观点：测压法在颈内静脉置管中的应用尚未得到证实

引用

麻醉与镇痛 2010年第5期6卷 8-9页

作者： Bruce j. leone, md 蒋嘉(译) 岳云(校) Department of Anesthesiology Mayo Clinic Jacksonville Florida 不详

在近期的《麻醉与镇痛》杂志中，Ezaru等。给出了15年问有关颈内静脉置管和意外颈动脉置管的数据。在经历了一次警讯事件之后，Ezaru等作者制定了一项强制性政策，即在放置大口径导管之前，对延长管内回血的压力进行测量以确认套管针是... 详细信息

在近期的《麻醉与镇痛》杂志中，Ezaru等。给出了15年问有关颈内静脉置管和意外颈动脉置管的数据。在经历了一次警讯事件之后，Ezaru等作者制定了一项强制性政策，即在放置大口径导管之前，对延长管内回血的压力进行测量以确认套管针是否在颈动脉内。据作者报道，15年间，在9859例颈内静脉置管的患者中，无一例发生意外动脉置管和动脉损伤的不良事件。因此，作者建议将这种简单的测压法常规用在颈内静脉导管置入之前，以避免动脉置管和损伤。

关键词：颈内静脉置管测压法应用动脉置管静脉导管置入动脉损伤大口径导管颈动脉内

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

反方观点：β-受体阻滞剂适用于所有行非心脏手术的高风险患者

引用

麻醉与镇痛 2008年第1期4卷 14-17页

作者： Martin j. London, md 尚游(译) 姚尚龙(校) Department of Clinical Anesthesia University of California San Francisco San Francisco California 不详

尽管麻醉学家很早就认识到，在围手术期使用β受体阻滞剂可以减轻肾上腺素能“应激”，但是最近，一些专家重新提出重视使用“围手术期B受体阻滞剂”（perioperative β-blockade，PBB）这一观点。这一热潮主要与两篇仍存在争议的早期... 详细信息

尽管麻醉学家很早就认识到，在围手术期使用β受体阻滞剂可以减轻肾上腺素能“应激”，但是最近，一些专家重新提出重视使用“围手术期B受体阻滞剂”（perioperative β-blockade，PBB）这一观点。这一热潮主要与两篇仍存在争议的早期研究报道有关，一份报道来自新英格兰医学杂志心，另一份则是1997年美国内科医师学会发布的围手术期应用PBB的试验性推荐。随着PBB被健康研究机构和质量报告指定为首选的“安全措施”，人们对于PBB的兴趣已经达到“狂热”的程度。在追求最佳患者预后的医师眼中它是“值得高度期待”的方法；热衷于改善医院状况的医院管理者将它作为“安全医疗”的保障。近期，研发性能改善措施的行政管理机构将其视为基础医疗和减少费用的方法。然而，接受过以经典流行病学技术评估治疗效能（如：严格控制实验条件得出的结果，诸如有严格纳入和排除标准的随机临床试验）和治疗效果（如：从大规模临床试验得出的结果）教育的临床医生和研究人员，从一开始就对PBB持怀疑态度。

关键词： β-受体阻滞剂非心脏手术高风险围手术期应用内科医师学会大规模临床试验医院管理者 β受体阻滞剂

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：