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951.
RF系列SF6气体回收净化再生系统在高压开关中的应用 总被引:2,自引:0,他引:2
RF系列SF6气体回收净化再生系统具有便于移动、回收时间短、回收利用率高、自动化程度高等优点。介绍了RF系列SF6回收系统的技术及所获专利,通过应用实例,证明RF系列SF6气体回收净化再生系统在高压开关中已被广泛应用并得到用户的认可。 相似文献
952.
Carlos Romero‐Nieto Stefan Durben Ila M. Kormos Thomas Baumgartner 《Advanced functional materials》2009,19(22):3625-3631
This paper describes a structure–property study using two dithieno[3,2‐b;2′,3′‐d]phosphole building blocks for the generation of white light emission and the incorporation of these units in a single polystyrene material. The emission of one of the light‐emitting organophosphorus building blocks can efficiently be switched from orange to green by simple protonation of the amino functional groups that are part of the π‐conjugated scaffold. The resulting three components (blue, green, and orange) exhibit photophysical properties that allow for an efficient fluorescence resonance energy transfer (FRET) in the mixture/polymer and provide intense white fluorescence upon excitation of the blue component; the fluorescence is close to pure white in solution and similar to the emission of an incandescent light bulb in the thin film. The results nicely illustrate the intriguing features that can be obtained by exclusively using organophosphorus‐based organic electronic materials. 相似文献
954.
955.
杨云峰 《电脑编程技巧与维护》2013,(8):69-70
安全、稳定和高速传输已经成为衡量园区网建设成功与否的重要标准,结合园区网的现状,通过配置PVLAN(PrivateVLAN)交换机,展现PVLAN在园区网中的特性和QOS(QualityofService)优势,为园区网的长期建设提供有力的技术支持。 相似文献
956.
Ali Koşar 《国际能源研究杂志》2011,35(11):1004-1013
A parametric study of thermoeconomic performance over four micro pin fin heat sinks of different spacing and shapes was conducted. Unit cost per product exergy, relative cost difference, and exergo‐economic factor were utilized to evaluate the thermoeconomic performance. The effect of working fluid on the thermoeconomic performance was also investigated using R‐123 and water as working fluids. Unit costs per product exergy were obtained to evaluate the product costs (total exergy change between exit and inlet streams) in micro pin fin heat sinks at fixed mass flow rate and fixed pressure drop. The results of the thermoeconomic analysis were compared with the results of a past exergy performance study by the author. In the light of raw experimental data acquired from the past studies of the author, important differences between the results of exergy and exergo‐economic performances were observed. It was found that the unit cost of exergy change decreased as electrical power increased and the relative cost difference approached to unity at high electrical powers (greater than 20 W). Moreover, high exergo‐economic factor values (more than 0.5) were obtained at low electrical powers while exergo‐economic factors had a small value at high electrical powers. When looking at the effect of the working fluid, higher cost per Watts of the products (up to the double of R‐123) was obtained with water compared with R‐123 at both fixed mass flow rate and pressure drop. No significant effect of pin fin spacing on the unit cost of exergy change was observed at fixed mass flow rate, while higher unit costs (up to 102%) were recorded at fixed pressure drop for scarcely packed pin fin heat sinks. Finally, the unit cost of exergy change was found to be independent of pin fin shape at fixed mass flow rate, whereas at fixed pressure drop, the hydrofoil‐based pin fin heat sink had higher unit costs (up to 1.8 times as much) when compared with the unit costs of pin fin heat sinks having flow separation promoting pin fins. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
957.
A cryogen-free cold source for temperature below 6 K without mechanical, thermal and electromagnetic perturbations would be welcome in many sensitive applications. This article describes such a device (Energy Storage Unit-ESU) built to store 36 J between 3 K and 6 K. This ESU consists of a solid state enthalpy reservoir connected to a cryocooler by a heat switch. Its different parts as well as the experimental results are presented. The choice of Gd2O2S (GOS) as high specific heat solid material for the enthalpy reservoir is discussed. Tests in different conditions were performed. A very good agreement was found between the experimental data and those predicted using the heat switch characteristics and the specific heat measurements of the GOS used in this experimental set-up. A stable 6 K temperature was maintained during more than 50 min in a completely silent environment. A semi-continuous operation for this cold source was successfully tested during 2.5 h. 相似文献
958.
A modular upgrade design for packet transport switch nodes is presented where packet loss is dramatically reduced by intra‐module and inter‐module buffer sharing. This modular design offers significant cost and power reduction in a high‐data‐rate system where buffers are highly costly and power‐greedy. 相似文献
959.
Load-Balanced Optical Switch (LBOS) [20] ensures close-to-100% throughout and all-optical transmission between linecards. In this paper, we extend LBOS for multi-cabinet implementation. The challenges lie in the fact that the practical implementation requirements in single-cabinet LBOS become un-scalable for multi-cabinet scenario. First of all, we remove the restriction on LBOS that propagation delay (tp) between adjacent linecards must equal to the transmission time (tpkt) for sending one packet. The delay tp is relaxed to be any value, which can accommodate the long and unequal distances fibers among cabinets. Secondly, we outstrip the upper bound of switch size N = 160 in LBOS. The basic idea is that the adjacent linecards share an identical channel/wavelength. Then LBOS can be scaled to support the large switch size of multi-cabinet. Last but not least, a more feasible fair scheduler is devised to replace the original one in LBOS. The simulation results show that multi-cabinet LBOS yields a much better delay/throughput performance than other multi-cabinet optical switches (e.g. Fasnet [8]). 相似文献
960.