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91.
钢铁制造流程的能量流行为和能量流网络问题 总被引:1,自引:0,他引:1
为应对全球气候变化,钢铁工业在下一步技术转型中,应高度重视钢铁制造流程的能量流和能量流网络问题。本文从充分发挥钢厂三个功能的视角,阐述了钢铁制造流程中铁素物质流和碳素能量流的行为规律,提出了应注重与铁素物质流相关的碳素能量流的输入/输出特点和能量流网络构建以及相应的信息化集成调控的观点,剖析了钢铁工业节能减排的潜力,指出了提高钢厂综合竞争力和多方位服务于可持续发展的可能性,探讨了相关理论的建立、技术开发和工程化实施的策略等。 相似文献
92.
着重介绍金属切削液的分类、功能及其在轴承加工中的选用。在轴承加工中,一般有车削、铣削、钻削、铰削和磨削等多种加工工艺,其中磨削加工是一道非常重要的精密加工工序,如内圆磨削、外圆磨削、平面磨削和沟槽磨削等。轴承加工中使用的水基切削液不仅要具有冷却作用,还要有润滑、清洗和防锈的功能。重点介绍金属切削液的主要功能及其在轴承加工中的应用。 相似文献
93.
A common location of sporadic, usually unpredictable, premature failures of both SnPb and Pb-free solder joints is within the intermetallic bond to one of the contact pads. Cu pads tend to be less prone to such defects than Ni/Au coated pads, but one phenomenon is a cause of growing concern for high reliability applications. Sporadic intermetallic problems are notoriously difficult to screen for, but at least a number of them are detectable right after assembly. However, the occasional formation of a network of voids within the Cu3Sn layer forming when soldering to Cu pads is rarely noticeable until much later. To make matters worse, efforts to establish practical engineering tests for purposes of identification and screening have usually not been successful.The root cause of the so-called ‘Kirkendall voiding’ has been shown to be associated with the quality of the electroplated Cu, apparently as determined by the incorporation of minute amounts of specific organic impurities. The present work describes and discusses a series of potential tests that allow the sorting of electroplated Cu in terms of its propensity for Cu3Sn voiding during soldering and subsequent aging. The times and efforts involved in these tests differ greatly, as do their effectiveness and accuracy. Individual tests may therefore be useful at various stages from supplier qualification to monitoring of batch to batch variations. 相似文献
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95.
奥氏体不锈钢中铁素体含量既有有利的一面也有不利的影响,本文根据在实际工作中遇到具体的一种管材就此问题进行了分析和实验,对保证施工质量,防止炉管焊缝铁素体含量超标,有一定指导作用。 相似文献
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98.
Liquid desiccant regeneration has important effect on performance of a liquid desiccant air conditioning system. Compared with conventional packed regenerator, internally heated regenerator is proposed to achieve better regeneration performance. This study emphasized on both regeneration rate and regeneration thermal efficiency to evaluate the performance of both regenerators. A validated heat and mass transfer model was used to analyse and compare the performance of internally heated and adiabatic regenerators. The results indicated that internally heated regenerator not only could increase the regenerate rate, but also could exhibit higher energy utilization efficiency. Different from adiabatic regenerator, internally heated regenerator can provide comparable regeneration efficiency and regeneration rate at low desiccant flow rate, so it should be a good alternative to avoid carryover of desiccant droplets. Higher air flow rate would result in a deduction of regeneration thermal efficiency although achieving higher regeneration rate. Suitable flow rate of the air should be considered carefully in liquid desiccant regeneration. The internally regenerator could have considerable prospect in liquid desiccant air conditioning application. 相似文献
99.
100.
Yinshun WANG Xiang ZHAO Junjie HAN Huidong LI Yin GUAN Qing BAO Xi XU Shaotao DAI Naihao SONG Fengyuan ZHANG Liangzhen LIN Liye XIAO 《Frontiers of Electrical and Electronic Engineering in China》2009,4(1):104-113
Abstract A 630-kVA 10.5 kV/0.4 kV three-phase high temperature superconducting (HTS) power transformer was successfully developed
and tested in a live grid. The windings were wound by hermetic stainless steel-reinforced multi-filamentary Bi2223/Ag tapes.
The structures of primary windings are solenoid with insulation and cooling path among layers, and those of secondary windings
consist of double-pancakes connected in parallel. Toroidal cryostat is made from electrical insulating glass fiber reinforced
plastics (GFRP) materials with room temperature bore for commercial amorphous alloy core with five limbs. Windings are laid
in the toroidal cryostat so that the amorphous core operates at room temperature. An insulation technology of double-half
wrapping up the Bi2223/Ag tape with Kapton film is used by a winding machine developed by the authors. Fundamental characteristics
of the transformer are obtained by standard short-circuit and no-load tests, and it is shown that the transformer meets operating
requirements in a live grid.
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Translated from Proceedings of the CSEE, 2007, 27(27): 24–31 [译自:中国电机工程学报] 相似文献