关键词： 应用   平衡   离合器   消费者与供货者的关系   定义   设计   英语   挠性联轴器   气体   汽油   工业   杠杆作用   负载物传送   厂商试验   机械驱动   矿物油   多语种的   天然气   天然气工业   石油工业   定货人   石油   动力传输   动力传动工程   质量保证   质量控制   卖货商   联轴器   规范   技术数据单  

标准号: NF M87-234-2010

摘要： La présente Norme internationale spécifie les exigences applicables aux accouplements permettant la transmission de puissance entre les arbres rotatifs de deux machines pour des applications d'usage général dans les industries pétrolière, pétrochimique et du gaz naturel. Ces applications exigent généralement que les accouplements transmettent la puissance à des vitesses ne dépassant pas 4 000 r/min, entre des machines dans lesquelles la première vitesse latérale critique est supérieure à la plage de vitesses de marche (machines à arbre rigide). Ils peuvent, sous réserve d'un accord, être utilisés pour des applications en dehors de ces *** présente Norme internationale est applicable aux accouplements conçus pour compenser un déport parallèle (ou latéral), un désalignement angulaire et un déplacement axial des arbres sans imposer aux machines couplées une charge mécanique excessive. Les accouplements couverts par la présente Norme internationale comprennent les accouplements à denture (et autres types de contact mécanique), les accouplements à éléments flexibles métalliques et divers accouplements en élastomère. Ces accouplements peuvent avoir une construction tout métal ou peuvent contenir des composants en matériaux non métalliques, tels que des *** présente Norme internationale couvre la conception, les matériaux de construction, le contrôle et les essais des accouplements ainsi que les méthodes de fixation de l'accouplement sur les arbres (y compris les dispositifs à douille conique et autres dispositifs spéciaux).La présente Norme internationale n'est pas applicable aux types spéciaux d'accouplements, tels que les accouplements à embrayage, hydrauliques, à courant de Foucault, rigides et à cannelures *** présente Norme internationale ne définit pas de critères de sélection des types d'accouplements pour des applications spécifiques.

关键词： left ventricular function   hemodynamics   angioplasty   heart-assist device   pressure-volume relations  

摘要： Objectives: We studied online left ventricular (LV) dynamic effects of mechanical LV unloading directly after percutaneous coronary intervention (PCI). Background: Limited clinical information is available on the direct LV dynamic consequences of LV unloading in patients undergoing high-risk PCI and primary PCI for acute ST-elevation myocardial infarction. Methods: The effects of the Impella LP2.5 device on LV dynamics were studied in 11 patients (elective high-risk PCI, n = 6;primary PCI, n = 5). LV pressure and volume were continuously assessed by a pressure-conductance catheter at 4 different support levels of the Impella, from 0 L/min at baseline to 2.5 L/min at maximal support. Results: The response to increased LV unloading was not different between both groups of patients. The pooled data showed no change on global and systolic LV function during increased LV unloading, while diastolic function showed improvement as indicated by an increased LV compliance in all patients. There was a decrease in end-diastolic pressure from 22 +/- 12 to 13 +/- 9 mm Hg (P = 0.0001), in end-diastolic elastance from 0.134 +/- 0.060 to 0.091 +/- 0.064 mm Hg/mL (P = 0.009), and in end-diastolic wall stress from 84 +/- 50 to 47 +/- 39 mm Hg (P = 0.004). Conclusions: LV unloading decreases end-diastolic wall stress and improves diastolic compliance dose-dependently. Our results indicate beneficial LV unloading effects of Impella during high-risk and primary PCI. (C) 2009 Wiley-Liss, Inc.

关键词： 工程机械行业   混合动力   技术开发   展望   革新   环保问题   技术方向   厂商  

摘要： 当全球都在关心环保问题的时候，工程机械行业有责任和义务为此做出努力。于是，混合动力工程机械的技术开发成为众多厂商追逐的热点。混合动力似乎是可以预见的未来工程机械行业的主导技术方向，但这并不意味着混合动力一定会有美好的未来。

关键词： DADS   ADAMS   平行四边形机构  

摘要： 本文针对铸铝生产线上的铝锭搬运工况,设计了搬运机械手,并从设计的要求出发,运用计算机系统动力学理论进行运动学建模,利用DADS(动力学分析设计系统)对该模型进行了深入分析。最后通过ADAMS软件仿真,着重对关键部件吊臂进行了分析,分析结果表明该机械手较好地满足了生产线的实际需求。

关键词： 超磁致伸缩作动器   混合隔振器   非线性   动力学特性  

摘要： 以船舶动力机械的安装特性为背景,提出了以空气弹簧作为被动隔振元件、超磁致伸缩作动器作为主动隔振元件的船舶动力机械双层混合隔振系统。在第一压磁理论和Stone-Weierstrass定理的基础上,建立了该隔振系统的非线性动力学模型。通过数值仿真,研究了该系统中非线性参数与幅频特性的关系;分析了超磁致伸缩作动器的励磁电流对隔振效果的影响。

关键词： 《联合国气候变化框架公约》   混合动力   工程机械   《京都议定书》   哥本哈根   法律约束力   发展中国家   人类社会  

摘要： 2009年底，被称为二战结束后人类社会最重要的一次国际性会议哥本哈根联合国气候大会最终在通过《哥本哈根协议》后落下帷幕。这份不具法律约束力的协议维护了《联合国气候变化框架公约》及其《京都议定书》确立的“共同但有区别的责任”原则，就发达国家实行强制减排和发展中国家采取自主减缓行动作出了安排。

关键词： 混合动力技术   工程机械行业   浙江大学   制造企业   汽车行业   应用  

摘要： 王庆丰,工学博士,浙江大学教授、博士生导师。1995年赴日本日立建机(株)技术研究所进修。2001年7月至今任浙江大学机械电子控制工程研究所所长。王庆丰教授主要进行电液控制及节能技术、工程机械混合动力技术、精密机电控制等方面的科研与教学工作。在国际合作、教育部"985工程"和国家自然科学基金等的支持下,他在国内最早系统地开展了工程机械混合动力技术方面的研究工作,最早建立了工程机械混合动力系统的实验平台,在混合动力挖掘机的动力系统结构、仿真、参数匹配、控制。

关键词： Computational chemistry   Molecular dynamics   Molecular modelling  

摘要： The first, long time scale (16-ns) ligand field molecular dynamics (LFMD) simulations of the oxy form of tyrosinase are reported. The calculations use our existing type 3 copper force field for the peroxido-bridged [Cu2O2](2+) unit which is here translated from MMFF into the AMBER format together with a new charge scheme. The protein secondary and tertiary structures are not significantly altered by removing the 'caddie' protein, ORF378, which must be bound to tyrosinase before crystals will grow. A comprehensive principal component analysis of the Cartesian coordinates from the final 8 ns shows that the protein backbone is relatively rigid. However, the significant butterfly fold of the [Cu2O2](2+) moiety observed in the X-ray structure, presumably due to the caddie protein tyrosine at the active site, is absent in the simulations. LFMD gives a clear and persistent distinction between equatorial and axial Cu-N distances, with the latter about 0.2 angstrom longer and remaining syn to each other. However, the two coordination spheres display important differences. LFMD simulations of the symmetric model complex [mu-eta(2) :mu(2)-O-2{Cu(MeiM)(3)}(2)](2+) (Meim is 5-methyl-1H-imidazole) provide a mechanism for syn-anti interchange of axial ligands which suggests, in combination with the old experimental X-ray data, the new LFMD simulations and traditional coordination chemistry arguments, that His(54) on Cu-A is 'insipiently axial' and that a combination of a butterfly distortion of the [Cu2O2](2+) group and a rotation of the Cu-A(His)(3) moiety converts the vacant, initially axial, binding site on Cu-A into a much more favourable equatorial site.

关键词： mechanical stimulation   periodontal disease   rat   fibroblasts   collagen   proliferating cell nuclear antigen  

摘要： Background and Objective: Elimination of pathogens is the main aim of periodontal treatment;however, modulation of the host immune response should also be considered. This study aimed to evaluate the effects of mechanical stimulation on periodontal healing in rats. Material and Methods: Before starting the experiment, lipopolysaccharide and proteases were applied once a day, for 4 wk, to both maxillary first molars of 30 rats to induce periodontal disease, and the application was stopped at the end of the 4-wk period. The experiment started immediately following this pretreatment. In the experiment, the left palatal gingiva was stimulated once daily using a powered toothbrush and the right gingiva served as a control (no mechanical stimulation). Pathological changes, and proliferation and cell death in periodontal tissues, were evaluated histometrically and immunohistochemically at baseline (0 wk), and at 1 and 3 wk of stimulation. Results: The control showed a reduction of polymorphonuclear leukocyte infiltration in connective tissue and an increase in the numbers of gingival and periodontal ligament fibroblasts. Mechanical stimulation reduced polymorphonuclear leukocyte infiltration and the area of destroyed collagen in connective tissue, and increased the number of gingival fibroblasts;however, it had no effect on alveolar bone and root resorption or on the number of periodontal ligament fibroblasts. Conclusion: Mechanical stimulation accelerated the healing of gingival inflammation by reducing the infiltration of polymorphonuclear leukocytes and enhancing fibroblast proliferation and collagen synthesis.

关键词： MOLECULAR dynamics   PALLADIUM   INTERFACES (Physical sciences)   METALS   NANOPARTICLES  

摘要： The mechanical properties of extended palladium nanocontacts have been investigated by the molecular dynamics method. The characteristic interatomic distances in the contacts have been determined and the process of the formation of palladium atomic contacts undergoing breaking has been studied for the (100), (110), and (111) orientations of the contact-surface interfaces.