胶管胶带用硫化剂和防老剂

越来越高的汽车发动机温度对在汽车中使用的胶管和胶带用聚合物提出了更严格的要求。本综述了胶管和胶带中使用的聚合物，并针对提高耐热、耐屈挠疲劳和耐臭氧老化性能讨论了每一种聚合物用的硫化体系和防老剂搭配。     

A Mechanism for the Oxidation-Related Influence on the Thermoelectric Behavior of Palladium

Oxidation of thermocouple elements can degrade the accuracy of thermocouple-based temperature measurements. As a particular example of such effects, oxidation of the Pd element of a platinum/palladium thermocouple is known to increase the thermoelectric emf by an amount equivalent to a temperature change of the order of 100 mK to 200 mK at 420 °C (G. W. Burns, D. C. Ripple, Proceedings of TEMPMEKO ‘96, 6th International Symposium on Temperature and Thermal Measurements in Industry and Science. Levrotto and Bella, Torino, 1997, 171–176). A possible physical mechanism to explain how oxidation affects the thermoelectric output of a Pt/Pd thermocouple is proposed. The analysis hinges on the hypothesis that the oxide-induced strain within the Pd thermoelement leads to a change in the Seebeck coefficient, and therefore to the thermoelectric emf. A theoretical model relating deformation of the palladium lattice to the change in the Seebeck coefficient is presented. The level of agreement between the calculation and the experimental observations suggests that oxide-induced strain in the Pd thermoelement is a likely explanation for the change in thermoelectric output of a Pt/Pd thermocouple within the temperature range where oxidation is active.     

A method for evaluation of an optical image stabilizer in an image sensor module

A figure of merit called the image clarity index is proposed for quantifying the performance of an optical image stabilizer (OIS) subjected to hand jitter. The image clarity index is defined as the slope angle of the normalized edge spread intensity of a captured image. A two-dimensional map of the index can offer clues as to the design limit on shake angle and frequency. Because of its relative simplicity over the existing metrics such as the modulation transfer function, the proposed index is especially suitable for summary evaluation of OISs and rapid benchmarking of OIS-equipped image sensor modules.     

Numerical simulations of the combustor for waste insulating oil containing polychlorinated biphenyls

Polychlorinated biphenyls (PCBs) are classified as persistent organic compounds and used in many industries because they are incombustible, heat resistant and electrical insulators. Owing to their strong toxicity and bioaccumulative nature, their transboundary movements are controlled by the Basel Convention and their levels are monitored by United Nations Environment Programme (UNEP). One of the most general methods for treating PCBs-containing waste is high-temperature decomposition; the removal efficiency of PCBs is 99.999% at over 1200°C for a retention time longer than 2 s. However, relatively low temperatures or low oxygen levels can produce highly toxic substances such as dioxins and dibenzofurans. Therefore, the reactor for the decomposition of PCBs should be very carefully designed. In this study, numerical simulations have been carried out to design a reactor for waste insulating oil containing PCBs. The flow patterns and temperature distributions of the gas in the reactor are examined. The path lines of the fluid particles are analyzed from the numerical results and the detention time of the PCBs-containing oil in the reactor is calculated. On the basis of this result, we try to scale up from a pilot plant to a commercial plant.     

Pacing impedance variability in tined steroid eluting leads

The aim of the study was to investigate pacing impedance (PI) behavior in ambulatory patients. Eighteen atrial and 18 ventricular tined steroid eluting leads with 1.2-mm2 and 5.6-mm2 electrodes were implanted in 20 patients. At 9-27 months after implantation PI was measured automatically by means of additional algorithms downloaded via telemetry links into implanted Thera pulse generators. PI was determined based on the voltage drop on the output capacitor during the 5 V-1 ms pacing impulse, at the programmable sampling rates from 1 second to 30 minutes. The study examined in particular: (1) PI trends and variations associated with different breathing patterns, body postures, provocative maneuvers, bike exercise, and during 24 hours; (2) impact of pacing rate and AV-delay on PI; (3) correlation between PI variability and pacing threshold, lead configuration, absolute PI value, age, gender, disease, and cardiac chamber. The most important findings were: (1) large PI variations of up to 450 omega were observed in properly functioning leads, (2) PI variability exhibited a weak negative correlation with pacing thresholds as if electrode positional stability was not a major factor underlying PI variations, (3) unipolar and bipolar PI variations were equivalent to each other (correlation factor = 0.93) implying that PI was mostly dependent on the circumstances around the lead tip.     

Experimental study on axial stratification process and its effects (I)-Stratification in Engine-

This paper is the first of several companion papers, which investigate axial stratification process and its effects in an SI engine. The axial stratification is very sophisticate phenomenon, which results from combination of fuel injection, port and in-cylinder flow and mixing. Because of the inherent unsteady condition in the reciprocating engine, it is impossible to understand the mechanism through the analytical method. In this paper, the ports were characterized by swirl and tumble number in steady flow bench test. After this, lean misfire limit of the engines, which had different port characteristic, were investigated as a function of swirl ratio and injection timing for confirming the existence of stratification. In addition, gas fuel was used for verifying whether this phenomenon depends on bulk air motion of cylinder or on evaporation of fuel. High-speed gas sampling and analysis was also performed to estimate stratification charging effect. The results show that the AFR at the spark plug and LML are very closely related and the AFR is the results of bulk air motion.