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关键词： 虚假广告   农民   创业   信息社会   离合器   投资   企业   现金  

摘要： 在当今信息社会,农民朋友免不了要和广告打交道,而识别真假广告尤为重要.日前,有位农民在报刊中看到河南一家企业登有“我厂投资联合办厂”的广告,广告中承诺加工离合器,可按月现金结算并免费供散件和技术指导,信以为真的农民多次与“厂方”联系,并多次寄款给对方,结果上当受骗.

关键词： HYDRAULIC machinery   SEWAGE -- Purification   DREDGING   HYDRAULIC engineering -- Equipment & supplies   WASTEWATER treatment  

摘要： The article discusses the use of hydraulic clutches in the equipment built for dredging up and removing sludge from wastewater treatment settling ponds. Disengaging the clutch results in the removal of the hydraulic pump from the power train, which leads to zero energy usage. Doing thus saves energy over running the pump in standby mode, and also reduces wear and tear on the pump.

关键词： Hydrostatic axial piston pump   Bearing/sealing part   Surface non-flatness   Cylinder barrel   Valve plate   CYLINDER BLOCK   RUNNING-IN   MOTORS  

摘要： The objective of this application study was to investigate the effect of surface non-flatness on the lubrication characteristic of the bearing/sealing part between cylinder barrel and valve plate in a hydrostatic axial piston pump. A developed numerical algorithm facilitated the simultaneous calculation of time-varying cylinder pressure, rotating body motion, and fluid film pressure to observe fluid film geometry and power loss. It was shown that an ideally flat surface might not form full fluid lubrication film properly, and that small-scale machining error, surface waviness, may increase the film thickness to some degree. The shape model of surface waviness considered waviness unit shape as well as its surface lay. However the results demonstrated that surface non-flatness of such small scale did not form the desirable fluid film geometry which minimized the power loss yet. Providing some surface design tips, two particular curved surfaces whose pressure-generating mechanisms differ were selected and analyzed in variation with their shapes and operating conditions. This study asserted that a circumferentially wavy surface would make better performance of motion stability and power efficiency than a radially wedged land surface, and finally that the non-flatness design strategy should be applied with re-considering the clamping ability.

关键词： Ovarian cancer-initiating cells   CICs   Cisplatin   SDF-1-CXCR4 axis   Migration   Invasion   DOWN-REGULATION   CXCR4   SURVIVAL   ALPHA  

摘要： In ovarian cancer, CD44+/CD117+ stem cells, also known as cancer-initiating cells (CICs), are highly proliferative and invasive. Therefore, the CD44+/CD117+ subpopulation is thought to be an important target for novel therapeutic strategies. In this study, we investigated the effects of cisplatin (CDDP) on metastasis and invasion suppression of ovarian CICs by targeting the CXC chemokine receptor-4 (CXCR4) signaling pathway in vitro and in vivo. CD44+/CD117+ ovarian CICs were enriched from human primary ovarian tumor tissues and confirmed by flow cytometry sorting. A 3-(4,5-dimethylthiazol-2-yl)-2.5-dipheny-tetrazolium bromide (MTT) assay revealed significant inhibition of proliferation of ovarian CICs with increasing CDDP drug concentrations. Moreover, colony formation and transwell migration assays indicated that CDDP significantly suppressed the invasive capacity of ovarian CICs in vitro. The expression levels of stromal cell-derived factor (SDF)-1, CXCR4, matrix metalloproteinase (MMP) 2, and MMP9 mRNA and protein levels were significantly reduced in CDDP-treated cells compared to untreated ovarian CICs. Furthermore, xenograft experiments confirmed that CDDP suppressed the growth of xenograft tumors formed by ovarian CICs in vivo. In addition, CXCR4 agonist (diprotin A) treatment of ovarian CICs weakened the effects of CDDP and enhanced SDF-1-CXCR4 axis expression in ovarian CICs. Thus, the SDF-1-CXCR4 axis is an important mediator of proliferation and invasion in CXCR4-overexpressing ovarian cancer-initiating cells (OCICs). Furthermore, CDDP inhibits invasion and metastasis of OCICs by targeting SDF-1-CXCR4 axis expression.

关键词： Atlanto-axial   C1-C2   Cervical trauma   Odontoid fractures   Posterior dislocation   Cervical traction   Vaccaro   ROTATORY DISLOCATION   SCREW FIXATION   SUBLUXATION   MANAGEMENT   COMPLEX   PLATE  

摘要： A case of traumatic posterolateral C1-C2 dislocation associated with odontoid fracture is reported. This is a rare case of traumatic posterolateral C1-C2 dislocation associated with odontoid fracture. Its managementis discussed. A traumatic dislocation of atlanto-axial joint associated with an odontoid fracture remains a rare injury. No case of posterior dislocation has been reported so far in the literature with this type of management. The case is of a 25 year-old-man with a primary atlanto-axial posterolateral dislocation associated with a type II displaced odontoid fracture without any neurological complication. The patient under went gentle traction during 24 hours with a halo frame. An incomplete reduction was achieved. Two days later, a complete reduction was obtained thanks to a preoperative manual traction maintained by a Mayfield (R) modified skull clamp. Anterior C1-C2 fixation was performed according to Vaccaro's technique. The patient wore a cervical collar and underwent physiotherapy during three months. To our best knowledge, this case represents the first traumatic atlanto-axial dislocation associated with an odontoid fracture which was treated through retropaharyngeal approach. This had been rendered possible thanks to the final reduction maneuver in extension. (C) 2014 Published by Elsevier Masson SAS .

摘要： The article reports on a marketing deal entered into by film producer Walt Disney Co. with Home Shopping Network (HSN) which involves the films 'Maleficient,' 'Cinderella' and 'The Hundred-Foot Journey.'

关键词： Multi-speed Transmission   Shift Sequence   Clutch Actuation   Output Speed   Transmission Control Unit  

关键词： 离合器   膜片弹簧   分离特性  

摘要： 为研究离合器膜片弹簧分离指在不同环境温度下的载荷-变形特性,建立了离合器膜片弹簧热传递模型,分析了膜片弹簧工作过程中热边界条件。利用ANSYS有限元软件建立了膜片弹簧有限元模型,分析了膜片弹簧在不同环境温度下小端载荷-变形特性,并通过试验验证了有限元分析结果的正确性和有效性。仿真与试验结果表明:离合器膜片弹簧小端载荷随温度升高呈现出减小的变化规律。

关键词： 油菜移栽机   槽轮送苗机构   优化设计  

摘要： 针对油菜移栽机设计了一套槽轮间歇式送苗机构。通过建立送苗机构的运动学与动力学模型,确定以送苗机构驱动扭矩最小为优化目标,以落苗时间与槽轮间歇停顿时间关系、链接数目与苗杯数量关系为约束条件,通过Matlab数值分析,得出满足约束条件的较优方案,即二指六槽式槽轮间歇机构驱动扭矩为87.2 N·m,间歇停顿时间为0.4 s。试验表明,优化后的机构运动流畅,送苗准确率可达92.9%。

关键词： 电磁离合器   结构原理   关键因素  

摘要： 电磁离合器的承载能力对汽车空调系统影响是比较大的,本文主要介绍电磁离合器的结构原理以及影响电磁离合器的承载能力大小的因素,提高离合器承载能力要靠设计制造、更要靠维护保养,为设计汽车空调系统提供依据。