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关键词： 自动变速器   平衡活塞   换挡控制   离合器   宝马   设计   厂家  

摘要： 各大变速器厂家在6挡自动变速器上都开始采用离合器平衡活塞的设计，尤其在宝马6HP系列的变速器中，几乎每一个离合器都采用了平衡活塞的设计。变速器厂家为何要这样设计呢？如前所述，这主要还是为了提高变速器换挡的速度，以便和双离合变速器进行竞争。

关键词： 兵器科学与技术   接合速度   分段控制   起步控制   干式离合器   自动机械变速器  

摘要： 建立起步过程动力学模型并提出了起步过程评价指标,选取转速、位移等为控制参量,设计了基于接合速度的干式离合器分段控制策略。设计了起步分段控制模型,利用试验数据库统计得出分段控制的主要参数阈值。对所设计的控制策略进行了实车平路起步试验。以当量冲击度、起步时间和滑转圈数为评价指标,分析了起步控制效果。结果表明,所设计的基于离合器接合速度的起步控制策略满足起步平稳性和快捷性的要求,为后续开展适应全工况的优化控制奠定了基础。

关键词： 离合器操控系统   电控液动气助力   温敏特性  

摘要： 为了提高电控液动气助力离合器自动操控系统对温度的自适应能力,从理论和实验两个方面研究了该系统的温敏特性。在试验数据的基础上建立了离合器自动操控系统接合速度与温度、占空比之间的经验公式,并在不同温度下通过试验对该公式的正确性和有效性进行了验证。试验结果表明:离合器操控系统温度模型建模的理论和方法正确,所得经验公式在实际运用过程中取得了理想的效果。

关键词： 离合器   检修   保养  

摘要： 本文以膜片弹簧离合器为例,讲述了离合器的使用与保养工作要点。

关键词： 全路面起重机   全球市场   产品   操控性   离合器   驾驶  

摘要： 马尼托瓦克向全球市场推出一款新型全路面起重机——格鲁夫GMK5250L，与近年推出的其它格鲁夫系列产品相比，此款新产品具有独特的创新，且性能领先同类产品。吊重250t的格鲁夫GMK5250L在5轴起重机中吊装能力最强，操控性佳，且驾驶舒适，是首款配备有VIAB启动缓速离合器的格鲁夫产品。

关键词： 干式DCT   EASY5软件   位移控制  

摘要： 简要介绍干式DCT液压控制系统,分析其工作原理及主要特点。深入分析离合器活塞位移控制系统的结构及工作原理,利用EASY5软件对其控制特性进行仿真研究,并通过试验验证仿真的正确性,为离合器扭矩传递的控制打下了基础,同时为控制策略的制定及控制系统的开发提供了依据。

关键词： Depression   Olfactory bulbectomy   Rolipram   Behavioral paradigms   Neurobiological markers   Oxidative stress   ELEMENT-BINDING PROTEIN   HIPPOCAMPAL CELL-PROLIFERATION   UNPREDICTABLE MILD STRESS   ELEVATED PLUS-MAZE   ADULT MALE RATS   NEUROTROPHIC FACTOR   MAJOR DEPRESSION   OXIDATIVE DAMAGE   HPA AXIS   PSYCHOTROPIC-DRUGS  

摘要： Olfactory bulbectomy (OBX) model has been proposed as a well documented model of depression. Accumulated evidences suggest that cAMP selective PDE4 enzyme plays an important role in the pathophysiology of depression disorder. Moreover, PDE4 inhibitors have shown antidepressant-like effect in behavioral despair models. However, the potential of PDE4 inhibitors to produce antidepressant-like effect in OBX model and their underlying mechanism(s) has not been adequately addressed. The present study was designed to investigate the possible antidepressant-like effects and underlying mechanism of rolipram in OBX model. The effects of rolipram were measured in a battery of behavioral paradigms, including hyperactivity in open field test (OFT), anhedonia behavior in sucrose consumption test, open arm activity in elevated plus maze test (EPM) and emotional scores in hyperemotionality test. The underlying signaling mechanisms were also investigated by measuring serum corticosterone (CORT), brain-derived neurotrophic factor (BDNF) and brain oxidant/antioxidant levels. Treatment with roliprarrx (0.5 and 1 mg/kg, p.o., 14 days) significantly improved the behavioral anomalies (decreased the hyperactivity, open arm activity and hyperemotionality scores, whereas, increased sucrose consumption), Further, rolipram significantly decreased the CORT level and increased cAMP, pCREB and BDNF levels. Additionally, rolipram reduced oxidative-nitrosative stress markers (lipid peroxidation and nitrite levels) and restored the antioxidant enzyme level, including reduced glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT), indicating attenuation of oxidative-nitrosative stress. Our results revealed that antidepressant-like effects of rolipram in OBX model may be mediated by modulating the hypothalamic-pituitary-adrenal (HPA) axis activity, increasing the cAMP signaling aspects and restoring the antioxidant mechanisms. (C) 2015 Elsevier Inc All rights reserved.

关键词： EQUIPMENT   rare earth elements   Magnetic force   electromagnetic system   Radiopharmaceuticals   high-coercivity   chemical production   Production Processes   METAL ALLOY   Rare earths   zinc oxide eugenol   Torque   Traction force   BARIUM FERRITE   base dimension  

摘要： The standard designs of magnetic systems and magnetic clutches with different high-coercivity permanent magnets (barium ferrite and from alloys of rare-earth elements), which are used in hermetic equipment for radiochemical and chemical production processes, are described. The basic dimensions and transmitting tractive forces and torques are presented.

关键词： 离合器   刹车带   制动轮  

摘要： 简述了JZC350混凝土搅拌机离合器工作原理,设计计算了内、外刹车带带宽和厚度、与制动轮间的压强、带与轮覆盖面单位面积上摩擦功率等参数。