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我国是煤资源大国，长期来在采煤的同时，抽放排空大量煤层瓦斯，不仅浪费大量资源，还严重污染大气。利用煤层瓦斯发电是解决煤层瓦斯放空的重要途径 。文章介绍一种全新的有别于传统 发动机的瓦斯内燃机空燃自动混合控制装置，其中包括：煤层瓦斯的理化特性、装置的结构、工作原理及工作过程，阐述了结构参数对发动机性能的影响。经过在中心瓦斯工区内燃发动机组群上安装试运行，结果表明：该装置可以适用于高、中、低不同浓度的煤层瓦斯，性能稳定、可靠，达到了设计性能指标，完全满足燃气,内燃机组的使用要求，并取得了很好的经济效益、生态效益和环保效益。     

轻型钢骨结构低层住宅设计荷载分析

本文讨论了北美低层钢骨结构住宅结构设计的荷载问题，包括各类荷载的取值和计算方法，以及荷载组合模式，并提出了在我国相关规范没有出台前，在国内进行设计时应该注意的一些问题。     

新疆三塘湖盆地侏罗系煤有机地球化学特征

有机地球化学和有机岩石学研究结果表明，新疆三塘湖盆地侏罗系煤中富集孢子体和角质体（３．０％～６．０％，全岩体积百分比），对煤中氯仿沥青“Ａ”组成中较高的总烃馏分（３０％～５０％）和饱芳比（０．６～３．０）产生了影响。煤的聚集环境是影响煤的显微组分组成及生油特性的关键因素。三塘湖盆地侏罗系煤属于“晚生晚排”叠加有“早生早排”类型的烃源岩。     

硅表面上的纳米量子点的自组织生长

纳米半导体量子点以其所具有的新颖光电性质与输运特性正在受到人们普遍重视。作为制备高质量纳米量子点的工艺技术 ,自组织生长方法倍受材料物理学家的青睐。而如何制备尺寸大小与密度分布可控的纳米量子点更为人们所注目。因为这是关系到纳米量子点最终能否器件实用化的关键。文中以此为主线 ,着重介绍了各种 Si表面 ,如常规表面、氧化表面、台阶表面以及吸附表面上 ,不同纳米量子点的自组织生长及其形成机理 ,并展望了其未来发展前景     

供热外网采用直埋式保温管的讨论

从工程投资,施工及保温材料的技术性能的分析入手,认为采用硬脂聚氨酯泡沫塑料保温的直埋管道比地沟管更具有优越性。     

Dynamic “Molecular Portraits” of Biomembranes Drawn by Their Lateral Nanoscale Inhomogeneities

To date, it has been reliably shown that the lipid bilayer/water interface can be thoroughly characterized by a sophisticated so-called “dynamic molecular portrait”. The latter reflects a combination of time-dependent surface distributions of various physicochemical properties, inherent in both model lipid bilayers and natural multi-component cell membranes. One of the most important features of biomembranes is their mosaicity, which is expressed in the constant presence of lateral inhomogeneities, the sizes and lifetimes of which vary in a wide range—from 1 to 10³ nm and from 0.1 ns to milliseconds. In addition to the relatively well-studied macroscopic domains (so-called “rafts”), the analysis of micro- and nanoclusters (or domains) that form an instantaneous picture of the distribution of structural, dynamic, hydrophobic, electrical, etc., properties at the membrane-water interface is attracting increasing interest. This is because such nanodomains (NDs) have been proven to be crucial for the proper membrane functioning in cells. Therefore, an understanding with atomistic details the phenomena associated with NDs is required. The present mini-review describes the recent results of experimental and in silico studies of spontaneously formed NDs in lipid membranes. The main attention is paid to the methods of ND detection, characterization of their spatiotemporal parameters, the elucidation of the molecular mechanisms of their formation. Biological role of NDs in cell membranes is briefly discussed. Understanding such effects creates the basis for rational design of new prospective drugs, therapeutic approaches, and artificial membrane materials with specified properties.     

用气冲气推成形触头造型机制造电机壳铸型的试验研究

扼要介绍了用气冲气推成形触头造型机制造电机壳铸型的成型过程及其实砂效果,试验结果表明,在工作气压为0,4￣0.45MPa的条件下,气冲气推成形触头造型机对电机壳类铸型的紧实,实砂效果十分理想,砂型紧实度高而且均匀。     

喷射成形GCr15钢的实验研究

应用喷射成形技术制备了GCr15钢沉积坯,同时收集了过喷粉末.采用金相显微镜、扫描电镜等对二者进行了研究.结果表明,过喷粉末大部分呈规则球形,但也有一些呈特殊形态.沉积坯中有些部位存在孔隙,等轴晶为其特征组织,晶粒大小分布具有一定规律.     

Effects of various environments on fatigue crack growth in Laser formed and IM Ti–6Al–4V alloys

The fatigue crack growth behaviors of Laser formed and ingot metallurgy (IM) Ti–6Al–4V alloys were studied in three environments: vacuum, air and 3.5% NaCl solution. Taking the Unified Fatigue Damage Approach, the fatigue crack growth data were analyzed with two intrinsic parameters, stress intensity amplitude ΔK and maximum stress intensity K_max, and their limiting values ΔK^* and . Fatigue crack growth rates da/dN were found increase with stress ratio R, highest in 3.5% NaCl solution, somewhat less in air and lowest in vacuum, and higher in IM alloy than in Laser formed one. In 3.5% NaCl solution, stress corrosion cracking (SCC) was superimposed on fatigue at R=0.9 for where K_max>K_ISCC, the threshold stress intensity for SCC. This and environment-assisted fatigue crack growth were evidenced by the deviation in fatigue crack growth trajectory (ΔK^* vs. curve) from the pure fatigue line where . Furthermore, the fractographic features, identified along the trajectory path, reflected the fatigue crack growth behaviors of both alloys in a given environment.     

装配式圆磨成形铣刀的结构设计

本文论述了装配式圆成形磨铣刀的应用特点，介绍了圆磨成形铣刀刀槽的三种槽形设计方法，推导出设计计算公式；对铣刀的几种装配夹紧结构进行了分析．最后，针对加工罗茨真空泵转子的实例进行了刀槽计算和结构设计。