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991.
衬底掺杂浓度对深亚微米槽栅PMOSFET特性影响 总被引:1,自引:1,他引:0
基于流体动力学能量输运模型,利用二维器件仿真软件MEDICI,对衬底掺杂浓度不同的深亚微米槽栅PMOSFET特性进行了研究,并与相应平面器件的特性进行了对比。研究发现,随着衬底掺杂浓度的提高, 与平面器件相同,槽栅器件的阈值电压提高,漏极驱动能力降低,抗热载流子能力急剧退化;但与平面器件相比,槽栅器件的阈值电压受衬底杂质浓度影响较小;漏极驱动能力及抗热载流子性能随衬底杂质浓度提高的退化则较平面器件小得多。 相似文献
992.
从管网设计以及炼铁理论两方面对马钢一铁厂目前合理富氧量进行了论述,得出了该厂富氧率可提高到3.37%-3.59%,从而进一步提高产量,使高炉利用系数达到2.505t/m^3.d。 相似文献
993.
The properties and electrocatalytic activity were studied of composite carbon‐supported materials based on heterocyclic polymer and nickel, in particular carbon/polyaniline/nickel, carbon/polypyrrole/nickel, carbon/poly(3‐methylthiophene)/nickel, as well as their precursors, carbon/polyaniline, carbon/polypyrrole, and carbon/poly(3‐methylthiophene). The materials were characterized by means of thermogravimetric analysis (TGA), scanning electron microscopy (SEM), EDAX, and electrochemical methods, such as cyclic voltammetry and linear voltammetry using RDE. SEM show porous materials, with a particle size of around 0.3 μm. It was found that in nickel‐modified catalysts between 5 and 6 wt % of nickel is obtained. TGA and FTIR show that the modification with nickel alters the polymer bonds. Curves from cyclic voltammetry show cathodic peaks corresponding to the oxygen reduction reaction (ORR) in all materials, occurring at relatively low potentials. Based on the potential range for ORR as well as kinetic parameters obtained from linear voltammetry using RDE, it was concluded that C‐Ppy‐Ni shows the best performance for ORR in acidic medium. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
994.
Jens Peter Hermes 《Electrochimica acta》2009,54(17):4258-2989
Doping front migration is a recently discovered effect occurring in sandwich structures composed of intrinsically conductive polymers. A system based on chemical or electrochemical doping is capable of controlling an integrated display and modifying the electrical resistance of the conductive polymer. The effect does not require a battery and is capable of monitoring time and temperature exposure. Low-cost devices using doping front migration could be the basis of a new class of smart labels for applications such as electronic “best before” labels on food and drink. 相似文献
995.
996.
探讨了聚氯乙烯各种阻燃剂的阻燃机理,研究了各种阻烯剂的没用量对制品氧指数及机械性能的影响。确定了半硬质阻燃聚氯乙烯套管的优化配方。 相似文献
997.
The ambient oxygen ingress rate method (AOIR) is an alternative method to Ox‐Tran for measuring the oxygen transmission rates (OTR) of whole packages. The objective of the present work was (a) to compare OTR values obtained by the two methods, and (b) to evaluate the use of the AOIR method for measuring OTR at realistic food storage temperatures and humidity levels. The AOIR method gave equal OTR values compared to the Ox‐Tran method for the five different types of whole packages used in the experiment, with OTR values in the range 0.06–1.48 ml O2/day. The repeatability of the AOIR method measured on an HDPE bottle was ±2.6% of the measured value in this experiment. This is slightly higher than the general specifications of the Ox‐Tran method (1% of reading for packages). However, the AOIR method can be considered to be a reliable, precise and cheap alternative method to the Ox‐Tran method for measuring OTR of whole packages. The capacity of the method is also high. The AOIR method showed satisfactory results when comparing OTR for packages tested under realistic food storage conditions covering 23°C/50% relative humidity (RH) and at 4°C/60% RH on the outside, combined with water (100% RH) or dry air inside the packages. Copyright © 2000 John Wiley & Sons, Ltd. 相似文献
998.
999.
C.P. Kaushik Ravinder Tuteja Namrata Kaushik J.K. Sharma 《Chemical engineering journal (Lausanne, Switzerland : 1996)》2009,155(1-2):234-240
The work is carried out to minimize the organic chemical load (unexhausted dye contents) in direct dyes effluent using low cost adsorbents. The studies are made with different direct dyes, i.e. Direct Red 28, Direct Yellow 12, Direct Orange 26 and Direct Blue 1 with various adsorbents. Three different bio/natural materials have been selected as adsorbents. These includes, Sugarcane bagasse pith (SB), Saw dust (SD)—the plant origin products, and Brick powder (BP)—a silica based material obtained from earth's crust on thermal heating. These substances are almost discarded waste products with the possibility of use as adsorbents. Experimental work for the dye removal from the effluent by activated charcoal (AC) has also been carried out and the results are compared with other adsorbents. The amount of unexhausted organic dye present in the effluent is measured as chemical oxygen demand (COD) before and after the treatment. Adsorbent Sugarcane bagasse pith shows good performance as compared to Saw dust and Brick powder. For understanding the behaviour of adsorbents Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and scanning electron microscopy (SEM) has also been carried out. 相似文献
1000.
根据色谱监测变压器H2含量异常的几种可能原因,对廊坊供电公司一起110kV主变单-H2组分严重超标的非典型故障进行了分析,找出了问题所在。 相似文献