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关键词： 离合器踏板   液压操纵机构   正确维护   锁紧螺母   增减垫片   调整   行程   螺栓  

摘要： 离合器踏板总行程的调整 采用增减垫片的方法，调整离合器踏板支架上的离合器开关限位螺栓，使踏板总行程为160—180毫米．调好后将限位螺栓用锁紧螺母锁紧。

关键词： 汽车离合器盖总成   试验台   加载盘   代分离轴承  

摘要： 汽车离合器盖总成检测试验台关键零部件的强度和刚度对试验台的测量精度影响较大,本文利用ANSYS有限元分析软件对加载盘和代分离轴承进行了强度和刚度校核,为试验台的设计和提高试验台精度提供了理论依据。

关键词： 主井提升系统   离合器   油缸  

摘要： 河南能源化工集团义煤公司千秋煤矿主井提升系统改造后,提升机离合器存在齿轮啮合不好、提升机工作时离合器有可能因误操作而打开等问题。根据实际情况对问题进行了分析,提出了安装控制闸阀、进行机械闭锁、断开电气控制线等措施对安全保护进行改进,并介绍了改进后钢丝绳的调节方法,为矿井提升系统的安全运行奠定了良好的基础。

关键词： 永磁同步交流伺服电机   扩展卡尔曼滤波器   故障诊断  

摘要： 采用扩展卡尔曼(EKF)的残差法对永磁同步电机故障进行检测,其目的是为了提高系统的鲁棒性,减少故障的漏报率,提高准确率。

关键词： Perfluoroalkyl and polyfluoroalkyl   substances   Audouin's gull   Three-egg clutches   Stable isotopes   Ebro Delta Natural Park   SPECIES LARUS-MICHAHELLIS   PERFLUOROOCTANE SULFONATE   PERFLUORINATED COMPOUNDS   MATERNAL TRANSFER   SELENIUM LEVELS   GLAUCOUS GULLS   EGGS   MERCURY   CONTAMINANTS   TISSUE  

摘要： The aim of the present study was to determine the distribution of per- and polyfluoroalkyl substances (PFASs) in three-egg clutches of Audouin's gull (Larus audouinii) breeding in Ebro Delta's colony according to the laying order (a, b and c eggs). Five PFASs were analyzed in 30 eggs (yolk and albumen separately), corresponding to 10 three-egg clutches. Carbon and nitrogen stable isotopes were measured as dietary tracers. PFASs were not detected in albumen. In egg yolks, perfluorooctane sulfonate (PFOS) was the main compound detected followed by perfluorononanoic acid (PFNA), perfluorohexane sulfonate (PFHS) and perfluorooctanoic acid (PFOA). Perfluorooctane sulfonate (PFBS) was not detected. Mean Sigma PFASs for a-eggs was of 236 +/- 57 ng g(-1) yolk wet weight (ww), for b-eggs was of 140 +/- 56 ng g(-1) yolk ww and for c-eggs, 133 +/- 54 ng g(-1) yolk ww. PFOS concentration decreased according to the laying order of the eggs, showing significant differences between consecutive eggs. In addition, significant ccirrelation (r(s)(2) = 0.7-0.9) was observed for PFOS concentration within the eggs from the same clutch. No relationship was found between PFOS levels and stable isotopes signatures. Capsule: In Audouin gull's eggs, PFOS was the main PFASs detected and its concentration decreased according to the laying sequence. (C) 2014 Elsevier Ltd. All rights reserved.

关键词： Tawny owl   PCB   DDE   PBDE   Bird eggs   TAWNY OWLS   REPRODUCTION  

摘要： Bird eggs are often used to measure various pollutants in monitoring programs. In protected species, however, it might only be possible to collect eggs abandoned by the parent birds. In order to assess the appropriateness of abandoned eggs for contaminant monitoring we examined intra-clutch variation in concentrations of 24 halogenated organic pollutants (16 organochlorines [OCs] and 8 brominated flame retardants) in six abandoned tawny owl (Strix aluco) clutches from central Norway. The variation among eggs within a clutch was low for nearly all compounds (intra-class correlation >0.9 both for lipid- and wet weight). This study suggests that abandoned eggs provide a relatively reliable measurement of lipophilic pollutants in clutches of terrestrial raptors such as the tawny owl. (C) 2014 Elsevier Ltd. All rights reserved.

关键词： Islands   Fire salamander   Ovoviviparity   Reproduction   Viviparity   EMBRYONIC-DEVELOPMENT   PARENTAL INVESTMENT   REPRODUCTIVE MODES   LACERTA-VIVIPARA   FIRE SALAMANDER   LIVE-BEARING   EVOLUTION   POPULATIONS   HISTORY   GROWTH  

摘要： Amphibian reproductive modes are diverse and are characterised by complex adaptations, including vast variability in life history traits and different parental investment strategies. For instance, viviparity is rare in urodeles despite the potential ecological advantages gained in such populations by having semi-independency from water. The fire salamander, Salamandra salamandra, shows remarkable intraspecific variation in reproductive modes, with two strategies co-occurring: a common reproductive mode, larviparity (parturition of aquatic larvae), and a phylogenetically derived reproductive mode, pueriparity (parturition of terrestrial juveniles). Pueriparous populations of S. salamandra have at least two independent origins, the first originating from its northern distribution in the Iberian Peninsula, and the second at two insular populations on the northwestern Iberian coast. Here, we analyse the patterns of variability of some life-history traits in larviparous and pueriparous populations of S. salamandra, including pueriparous populations from the two independent origins, to understand how these traits relate to the evolutionary transitions in reproductive modes in S. salamandra. Our study shows differences in female body size and clutch and brood size between larviparous and pueriparous fire salamanders. We did not find differences in female investment between reproductive modes, and thus, the evolution to pueriparity in S. salamandra is likely characterised by the re-allocation of eggs to matrotrophy. Our study also confirms pueriparity and larviparity as the characteristic reproductive modes for insular and coastal/mainland S. s. gallaica populations, respectively, revealing the potential presence of pueriparity in one coastal population. This comparative analysis sheds light on the maternal factors that might have driven, or are related to, the evolution of pueriparity in this unique biological system and sets up the basis for testing different hypotheses t

关键词： 4WD   Coupling devise   Wet clutch   Temperature estimation model   Generalized heat coefficient  

摘要： Due to the increasing demand for multi-purpose vehicles, there has been a noticeable increase in the sales volume of 4-wheel-drive (4WD) vehicles such as Sports Utility Vehicles (SUV). Most 4WD vehicles are equipped with a coupling device which transfers driving power to the rear drive shaft. In some severe operating condition, wet friction clutches in a coupling device generate enormous heat from friction and cause a sharp temperature increase. Excessive heat can cause thermal damage on the surface material of the clutch. Therefore, a method estimating temperature of the clutch is required to avoid thermal damage. This study suggests a method for estimating temperature of clutch. A full car dynamic model was constructed to simulate the severe driving conditions of a 4WD vehicle and the results of the experimental validation of the temperature estimation model are presented.

关键词： 离合器   自由行程   摩擦衬片   离合器踏板   分离轴承   球头   排除方法  

摘要： 农业机械是现代化农业的重要物质基础,是农业现代化的重要内容和标志。为了充分发挥农业机械在农业生产中的作用,农机驾驶操作人员必须合理使用农业机械,并进行科学维护保养,使其经常处于良好的技术状态。虽然单一机械技术比不上液压气动机电一体化,但是,目前我国现有的农业机械大多采用机械式传动方式。作为机械式传动系统主要构件之一的离合器,它的工作状态好坏,直接影响农业机械作业的效率。一、离合器的故障与排除方法

关键词： 离合器   海绵   普立  

摘要： 1.第一步就是先将离合器的外盖拆下,这是已经拆掉塑胶外盖,正在动手拆金属内盖时。2.继续拆,此时,离合器的防尘海绵已经拿下来了。附带一提,离合器防尘海绵也是消耗品,需要定期更换。3.拆下来的这部分就是所谓的CVT变速机构。4.这次更换的零件之一是后离合器的蹄片,理论上要用套筒把那颗六镙母拆下,可是我们找不到那么大的套筒,怎么解决呢?