SiH4、N2二元混合气在低O2态下的潜在危险性

通常硅烷与氧很难共存,人们也决不会贸然在硅烷气体中作掺氧试验。一次偶然的机会,我们做配制SiH4与N2二元混合气的实验,事后发现所用N2中含氧量为4．2％(体积分数)。由此我们知道这种处于亚稳状态的硅烷混合气其潜在的危险非常之大。     

化工标准与标准化概述

就我国标准化的历史与现状加以综述。对化工标准的分类、有效范围、执行方式以及化工标准的特点作重点论述。对我国现行化工标准的不足及发展趋势也加以阐述。对国际标准化机构的相关工作作了简要介绍。     

自主电控高压共轨柴油机冷起动控制策略研究

为了解决6DF2柴油机冷起动困难的问题,用自主开发的电控高压共轨系统取代原机所用的机械泵系统,并设计了起动控制策略,主要包括对主喷及预喷油量,主喷及预喷定时以及起动轨压的控制。试验结果表明,采用自主高压共轨系统及以上控制策略能在不增加任何硬件设备的基础上大幅提高6DF2柴油机的冷起动性能,满足实际车用柴油机的使用要求。     

自主共轨系统在CA4DC柴油机上的应用研究

对CA4DC柴油机的燃油系统进行了国产化研究：沿用原机的进气道和燃烧室方案,采用6×Φ0.14 mm喷油嘴方案,并匹配自主研发的高压共轨燃油喷射系统,通过对控制参数的详细标定,发动机外特性试验及负荷特性试验结果表明,匹配自主共轨系统的发动机完全满足国3排放标准。     

发动机喷嘴空化特性研究进展

在综述国内外研究发动机喷嘴的空化成因的基础上,系统报道了空化的影响与作用机理,以及研究空化的方法。提出了空化研究的数值模拟应考虑发动机实际工况时高温的影响,强调应该加强喷嘴的气蚀磨损和空化程度的最优化技术研究。同时,应该强化研究代用燃料的空化机理、影响特性和气蚀磨损机理,为发动机可代用清洁燃料的应用打下基础。     

乙硅烷的制备

概述了乙硅烷的制备方法并对各种方法进行了评价。     

碳/环氧复合材料C波段天线反射面研制

简述了碳/环氧复合材料C波段天线的组成,并对天线反射面制造工艺过程、材料选择及特性、铺层分析、成型模具设计、固化成型工艺参数选择、产品质量控制等内容进行了研究.结果表明:研制的某型号卫星蜂窝夹层结构复合材料抛物面天线的型面精度可控制在均方差精度为0.16 mm,经多次飞行试验考核,该天线各项指标均达到设计要求.     

Critical assessment of methods for measurement of temperature profiles and heat load history in microwave heating processes—A review

Limitations of microwave processing due to inhomogeneities of power input and energy absorption have been widely described. Over- and underheated product areas influence reproducibility, product quality, and possibly safety. Although a broad range of methods is available for temperature measurement and evaluation of time/temperature effects, none of them is sufficiently able to detect temperature differences and thermally induced effects within the product caused by inhomogeneous heating. The purpose of this review is to critically assess different methods of temperature measurement for their suitability for different microwave applications, namely metallic temperature sensors, thermal imaging, pyrometer measurement, fiber optic sensors, microwave radiometry, magnetic resonance imaging, liquid crystal thermography, thermal paper, and biological and chemical time-temperature indicators. These methods are evaluated according to their advantages and limitations, method characteristics, and potential interference with the electric field. Special attention is given to spatial resolution, accuracy, handling, and purpose of measurement, that is, development work or online production control. Differences of methods and examples of practical application and failure in microwave-assisted food processing are discussed with a special focus on microwave pasteurization and microwave-assisted drying. Based on this assessment, it is suggested that infrared cameras for measuring temperature distribution at the product surface and partially inside the product in combination with a chemical time/temperature indicator (e.g., Maillard reaction, generating heat-induced color variations, depending on local energy absorption) appear to be the most appropriate system for future practical application in microwave food process control, microwave system development, and product design. Reliable detection of inhomogeneous heating is a prerequisite to counteracte inhomogeneity by a targeted adjustment of process and product parameters in microwave applications.     

重型刮板输送机成套装备智能化关键技术

针对重型刮板输送机成套装备智能化对实现自动化无人工作面的重要性,指出了实现成套装备智能化的关键技术,比较分析了3种软启动技术,介绍了实现变频调速软启动的2种方法以及谐波抑制技术与变频控制系统,阐述了通过控制伸缩机尾油缸压力实现链条张力自动控制原理,利用霍尔传感器检测链条故障的传感装置,提出了刮板输送机远程工况监测诊断与控制系统的架构,最后指出了重型刮板输送机成套装备智能化亟待解决的问题。     

自主共轨系统在CA4DC柴油机上的应用研究

对CA4DC柴油机的燃油系统进行了国产化研究:沿用原机的进气道和燃烧室方案,采用6×Φ0.14 mm喷油嘴方案,并匹配自主研发的高压共轨燃油喷射系统,通过对控制参数的详细标定,发动机外特性试验及负荷特性试验结果表明,匹配自主共轨系统的发动机完全满足国3排放标准。