Accurate Measurements of Pressure-Viscosity Behavior in Lubricants

The piezoviscous effect is accurately characterized for a number of representative lubricating oil base stocks and a simple, well-defined hydrocarbon. Procedures for the generation of accurate pressure-viscosity coefficients are outlined. The reciprocal asymptotic isoviscous pressure may be measured to within perhaps 1%. The piezoviscous effect may be important to automotive fuel economy. The departure from exponential behavior at very low pressure becomes more pronounced at high temperature.     

Temperature Resistance of Russian Vacuum Lubricants

The temperature resistance of Russian vacuum lubricants is studied. The antifrictional properties of lubricants based on perfluoropolyethers are found to be similar: they ensure a low frictional coefficient at 30–300°C. The thermal stability is best for Amethyst and Nika lubricants.     

Wear Resistance of Amorphous-Crystalline Coatings with Lubricants

The results of tests of a Zr–Al–B boundary friction detonation coating in a wide range of changes under friction conditions have been presented. A comparative analysis of the obtained characteristics of friction and wear in order to evaluate the tribotechnical properties of amorphous-crystalline coatings has been carried out. These results have been compared with parallel tests of coatings based on tungsten carbide, samples of hardened steel and bronze, and the bearing of the sliding layer. The formation of solid solutions has been established and the introduction of oxygen in zirconium that corresponds to the formation on the friction surfaces of the secondary structures of the first type, a characteristic feature of which is their surface localization, ultra-dispersed structure, and ability to minimize disruption and shield unacceptable adhesion phenomena. The use of the Auger electron microscope confirmed that oxygen completely replaces the sulfur in the surface structures.     

湿度传感器电阻和电容分量测量方法的研究

高分子电阻型湿度传感器是一种有着广泛应用前景的新型湿度传感器，研究表明，对非纯电阻型湿敏元件，可将其等效为一电阻与电容的串联模型。文中提出了测量湿度传感器等效电路中的电阻分量只和电容分量C的实用方法，并介绍了该方法的工作原理，它是一种由传感器、标准电阻和运算放大器构成的负反馈电路。实验结果表明，该测量方法可用于精确测量湿度传感器的电阻及电容分量。     

Lubricants and the environment

About 1% of the total mineral oil consumption is used to formulate lubricants.Everywhere the production, application, and disposal of lubricants has to cover the requirements of the best possible protection of our nature and the environment in general and of the living beings in special. Often health hazards do not follow the direct way to human beings, more often they follow indirect routes through our environment.For all cases of direct contact between lubricants on one side and human beings and the nature on the other side the compatability has to be checked. The gaining necessity for environmental compatability tests has to be understood by all those who are working in the fields of production, application, and disposal of lubricants.Simplified it can be stated that health hazards and water hazards have to be minimized. Using the three examples Coolants and Metal Working Lubricants, Engine Oils, and Fast Biodegradable Lubricants and Operational Fluids some of the most important aspects of the impairment of the environment will be discussed.     

基于阻抗辨识和混杂控制的机器人辅助抗阻训练方法

现有机器人辅助抗阻训练方法大多是运用易受噪声干扰的患肢主动作用力或表面肌电信号直接进行治疗控制器设计,且在设计过程中未能同时将机器人连续变量运动控制与医师离散事件决策控制这种混杂特性融于统一框架内,具有一定的局限。针对上述问题,提出一种基于阻抗辨识和混杂控制的机器人辅助抗阻训练方法,该方法首先根据患肢主动作用力和实际运动位置在线辨识患肢时变生物阻抗;其次,运用混杂控制理论建立机器人辅助抗阻过程系统模型,根据患肢生物阻抗变化分别定义连续系统区域切换离散事件及离散系统控制状态,并基于混杂自动机设计离散事件决策控制器;最后,选用美国Barrett公司WAMTM柔顺机械臂构建康复试验系统,对所设计控制器进行有效性验证。试验结果验证了阻抗辨识和混杂控制理论应用于机器人辅助抗阻训练过程的有效性和实用性。     

Resistance of Fomblin Z-Type Lubricants to Lewis Acid-Catalyzed Decomposition: Effect of the Chemical and Electronic Structure of End-Groups

In the present paper, the effect of the chemical and electronic structure of the Fomblin Z-type lubricant end-group on the Lewis acid-catalyzed decomposition is studied by both Thermogravimetric Analysis (TGA) and Density Functional Theory (DFT) molecular orbital calculations. TGA results of the mixture of Z-type lubricants and ZrO ₂ show that the structure of the end-groups significantly affects the thermal stability of the lubricants in the presence of a Lewis acid. The DFT calculation results suggest that the reactivity of the end-groups and thus the resistance of various lubricants to Lewis acid-catalyzed decomposition are affected by the lubricant molecular orbital structure.     

Assessing the Effectiveness of Solid Lubricants

The effectiveness of a proposed solid lubricant is investigated, on the basis of the abrasive cutting coefficients. Its dependence on the grinding conditions, the characteristics of the boron-nitride wheel, and the alloying of high-speed steel is determined. The lubricant reduces the abrasive cutting coefficient by about 40–50%. A method is proposed for measuring the frictional coefficient. The benefits of lubricant application are assessed. The utility of the abrasive cutting coefficient in estimating the effectiveness of solid lubricant is confirmed.     

风机轴承座润滑油路的改进

针对设备原有的轴承座结构,分析了造成轴承润滑不良的原因,对轴承座进行了相应改造,解决了设备在生产过程中由于润滑不良造成的零件损坏及停机问题.     

薄型流场对燃料电池性能影响的交流阻抗谱法研究

利用交流阻抗测试法对采用薄型流场板的氢气/空气质子交换膜燃料电池单电池进行了表征。实验结果表明,阴极侧流场深度的减小对燃料电池性能的影响几乎可以忽略,而阳极侧流场深度对燃料电池性能的影响则相对较大。对具备不同形式与深度的阳极流场的单电池进行交流阻抗测试和分析,并辅以极化曲线测试,发现阳极侧流场深度从1.0mm的单路蛇形流场降低至0.4mm后,燃料电池在大电流密度下的性能受到影响;当电流密度大于1200mA/cm2时,电池的浓差极化进一步加剧,导致电池的最大输出功率略有下降。尽管如此,由于极板总体厚度的减小,电池的体积比功率密度仍得到很大程度的提高。     

Tribological Studies of Lubricants

This paper describes an upgraded installation, a procedure, and results of lubricants testing with respect to use in the executive mechanisms of space vehicles.     

绿色润滑剂的生物降解性及特点

阐述了绿色友好润滑剂的生物降解性和摩擦化学特点，提出了绿色润滑剂在发展过程中存在的主要问题，并对未来的发展趋势进行了预测。     

电容成像和电阻成像系统的敏感场电磁特性比较

基于有限元法对电容成像和电阻成像系统中的敏感场电磁特性进行比较,分别推导出电容成像和电阻成像系统中敏感场的数学模型和等价泛函,对两者的电磁特性及相互关系进行有限元法解析,为电容电阻复合成像系统的图像信息融合提供了理论依据。     

电容层析成像中电容检测方法的分析比较

介绍了电容层析成像中常用的电容检测方法电荷转移法、交流法以及差分采样法.分别从电路结构和工作原理等方面分析比较了每种测量方法的优缺点及适用的场合.     

电容层析成像中电容检测方法的分析比较

介绍了电容层析成像中常用的电容检测方法:电荷转移法、交流法以及差分采样法.分别从电路结构和工作原理等方面分析比较了每种测量方法的优缺点及适用的场合.     

液体空间润滑剂的现状与发展

空间润滑剂对于宇航飞行器的安全性,可靠性至关重要。综述了液体空间润滑剂的现状及发展,介绍了几种新型液体空间润滑剂的性能、合成方法。     

纳米添加剂在润滑剂中的应用现状

由于纳米材料具有很多独特的优点,因此纳米添加剂在摩擦学中得到了广泛的应用,最近又发现在噪声控制方面纳米添加剂具有一定的优势。综述了纳米添加剂在润滑剂中的分散稳定性,在摩擦学和噪声控制方面的应用,以及纳米添加剂的减摩抗磨机制。     

Deposit-Forming Tendencies of High-Temperature Lubricants

A laboratory unit is described with a method for determining the deposit-forming tendencies and oxidation stabilities of lubricants in thin films. The test oil is passed over a spinning aluminum disk heated to temperatures of 500–650 F, which provides a dynamic oil film of about 0.0003 inch thickness. Oxidation stability is determined by measurement of the oxygen consumed. The deposits on the disk are estimated visually. The test can be used for comparative evaluation of base fluids and inhibited fluids.

Test results on a series of high-temperature lubricants approximate deposition data obtained in jet engine tests and in CRC high-temperature bearing tests.     

环境友好润滑剂的特点及发展

阐述了绿色友好润滑剂的生物降解性和摩擦化学特点，提出了环境友好润滑剂在发展过程中存在的主要问题，并对未来的发展趋势进行了预测。