煤矿企业中电气设备的绝缘在线监测与状态检修

首先阐述了电气设备绝缘在线监测技术的各个发展阶段,接着对这种监测方法的原理、技术方法以及特点进行了详细的分析,最后提出了状态维修的意义以及绝缘在线监测与状态维修之间的相互关系、相互作用。     

锻锤基础的改造与施工

本文介绍长岭炼油厂机械分厂自由锻锤改造概况和施工中的技术措施。     

叶巴滩堆石混凝土二道坝温度应力仿真分析及温控措施研究

对位于高海拔地区的叶巴滩堆石混凝土二道坝工程开展全坝段温度应力仿真分析,重点研究大坝横缝分缝措施和混凝土表面保温措施对坝体温度应力的影响。结果表明：结构分缝措施可以降低坝体内部拉应力,设置1条横缝即可有效控制坝体内部高拉应力区范围,并使应力极值降低约0.8 MPa;混凝土表面保温措施可在秋冬季节显著降低大坝表层混凝土温降幅度,减小表层温度应力水平,使应力极值降低约0.6 MPa;叶巴滩二道坝设置1条横缝并采取表面保温可满足施工期温控要求。     

Development of a DC −1 MV insulating transformer for neutral beam injectors

A DC −1 MV insulating transformer has been developed for the power supply of the neutral beam injector (NBI ) at ITER (International Thermonuclear Experimental Reactor) . A DC long‐pulse −1 MV insulation structure between the primary and secondary windings, considering potential variation in the insulator for DC long pulse, has been designed. Simultaneous development of a compound bushing, which consists of an AC 500 kV condenser bushing inside a cylindrical fiber‐reinforced plastic tube, has been carried out. The DC −1 MV insulation design has been verified by high‐voltage insulation tests of AC 50 Hz 1300 kV peak for 1 min, DC −1200 kV for 1 h, and a long‐duration test of DC −1060 kV for 5 h. The results showed that the insulating transformer satisfies the power supply requirements for the ITER NBI . Copyright © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

造纸新产品--聚芳酰胺纤维纸

介绍了聚芳酰胺纤维纸的性能、生产原料及其特性、开发的技术关键等。     

SIMULATION AND EXPERIMENTAL STUDY ON THE AIR FLOW AND HEAT LOADS OF DIFFERENT REFRIGERATOR CABINET DESIGNS

As the economy has been growing in the past decade, consumers in Taiwan start to consider how to raise living quality. As people tend to adopt the westerners' living style of purchasing food once every week or two weeks. Large grocery stores, hence, have been built both in urban and suburban areas. This change results in a growing need of better-designed refrigerator-freezers (RFs). Consequently, consumers need RF models with better or more cooling functions, larger volumetric capacity, and efficient energy use

A 1997 top-mount refrigerator with a volume of about 460 liters was selected as the baseline model. This study used computer aided finite element methods (FEM) to analyse and establish designs for RFs. These designs included different insulation properties and various cool air flow rates and outlets in the freezer and fresh food compartments. The following outcomes were investigated in the simulating work:

•The thermal responses of the insulation material on RF cabinets

•The effect of a modified cool air outlet on the air flow distribution and heat loads

The simulation results were then compared with experimental data. Agreement was found between simulation and experimental results. This suggested that computer-aided simulation could serve as a reliable tool for other designs similar to cases practiced in this RF study.     

酚醛泡沫在外墙保温防火中的应用

简介了酚醛泡沫在建筑行业的应用现状,施工方法,提出了推动酚醛泡沫的应用的建议。     

积层线路板用液态感光成像油墨的应用研究

研究了积层线路板油墨的组成配方、制备和应用工艺,分析了不同预烘时间对油墨分辨率的影响以及过显和显影不足问题的形成,并从生产和实际操作的角度,提出了解决的方案。利用聚苯醚改性的环氧树脂,应用于油墨的配方中,改善了油墨固化后绝缘材料的耐热性、介电性等主要性能。油墨中改性环氧树脂的质量分数为13.0%时,固化后绝缘材料的玻璃化温度可达184.22℃,介电常数为3.19,介质耗损因数为0.019,可以作高频积层线路板的绝缘层。     

Thermal‐Insulation,Electrical, and Mechanical Properties of Highly‐Expanded PMMA/MWCNT Nanocomposite Foams Fabricated by Supercritical CO2 Foaming

Foaming behavior of poly(methyl methacrylate) (PMMA)/multi‐walled carbon nanotubes (MWCNTs) nanocomposites and thermally‐insulating, electrical, and mechanical properties of the nanocomposite foams are investigated. PMMA/MWCNT nanocomposites containing various amounts of MWCNTs are first prepared by combining solution and melt blending methods, and then foamed using CO₂. The foaming temperature and MWCNT content are varied for regulating the structure of PMMA/MWCNT nanocomposite foams. The electrical conductivity measurement results show that MWCNTs have little effect on the electrical conductivity of foams with large expansion ratio. Thermal conductivities of both solid and foamed PMMA/MWCNT nanocomposites are measured to evaluate their thermally insulating properties. The gas conduction, solid conduction, and thermal radiation of the foams are calculated for clarifying the effects of cellular structure and MWCNT content on thermal insulation properties. The result demonstrates that MWCNTs endowed foams with enhanced thermal insulation performance by blocking thermal radiation. Moreover, the compressive testing shows that MWCNTs improve the compressive strength and rigidity of foams. This research is essential for optimizing environmentally friendly thermal insulation nanocomposite foams with enhanced thermal‐insulation and compressive mechanical properties.     

保温对地热单井换热性能的影响分析

建立了单井地热传热数学模型,模拟了单井地热流动换热过程,比较分析了不同保温材料及保温深度对采出水温度和取热功率的影响。结果表明：保温材料热导率和保温深度对系统取热功率有很大影响。当保温材料热导率为0.03 W/( m·K)和0.5 W/( m·K)时,平均取热功率分别 为732.08 kW和640.98 kW;采用热导率为0.03 W/( m·K)的保温材料,保温深度1000 m时流体进出口温差为10.33 K,保温深度为2000 m时流体进出口温差为15.98 K,保温深度为3000 m 时流体进出口温差为17.93 K。实际工程中,可以采用各种材料组合安装的形式对采出井进行保温,保温重点为井深较小处,这样既能保证采出水温,又能节约成本。