汽车电子控制系统驱动保护电路的分析与设计

本文介绍了汽车电子控制系统驱动保护电路的设计,给出其各个组成模块的实例.     

后置蜗壳斜流风机整机数值模拟

使用商业软件Numeca的Fine／Turbo模块，对包含斜流叶轮与蜗壳一体的斜流风机进行整机计算。对一斜流风机在设计转速下不同工况点进行了数值模拟，并与试验结果进行了比较，吻合较好。通过特定截面的不同流动图谱，证实了蜗壳、叶轮相互作用引起的整机流场的不对称性。研究结果表明，叶轮内部叶顶间隙区二次流动和叶轮与蜗壳相互作用引起的涡系是影响斜流风机效率的主要原因。     

全球钛业回顾和展望

概述了磁光记录原理，介绍了磁光盘的基板材料，并重点阐述了稀土－过渡（ＲＥ－ＴＭ）合金非晶膜的制造方法，性能及其保护膜。另外还扼要介绍了氧化物单晶膜，多晶膜和多层超薄磁光记录膜的优缺点，并指出多层膜磁光记录材料是今后的发展方向。     

应力腐蚀门槛值和断口分形维的定量关系

建立了ＫＩＳＣＣ和断口分形维数ＤＦ之间的定量关系,根据分形几何原理对ＫＩＣ和ＫＩＳＣＣ的取向依赖关系进行了分析．     

Ti－24Al－11Nb腐蚀疲劳断口形貌的研究

Ｔｉ－２４Ａｌ－１１Ｎｂ腐蚀疲劳断口形貌的研究张跃，褚武扬，王燕斌，肖纪美（北京科技大学北京１０００８３）１引言对Ｔｉ－２４ＡＩ－１１Ｎｂ合金的断裂特征和断口形貌已进行了较多的研究［“］．在３００ｏＣ的氢气中该合金能发生氢致开裂，其断口形貌与过载断口...     

COLOURING OF PURE IRON AFTER Ti~＋-O~＋ DUAL ION IMPLANTATION

用电化学的方法对经Ｔｉ~＋－Ｏ~＋二重离子注入后的钝铁表面进行处理，可呈现出深蓝、海蓝、褐、紫、金黄、淡黄等颜色用Ｘ射线光电子能谱（ＸＰＳ）对着色表面进行分析，发现表层有ＴｉＯ＿２富集，证明存在钛的氧化物是着色的必要条件．同时着色后的表面存在Ｔｉ的浓化层，着色的深浅程度与钛的浓度有关     

含跨季节储热的多能互补分布式能源系统容量配置优化

为了满足我国对环保及能源的需求,多能互补分布式能源系统成为了分布式能源系统的发展的趋势。文章针对北京地区某办公建筑构建了含跨季节储热的多能互补分布式能源系统,以年总成本最低为目标函数,在满足全年负荷的情况下利用PSO算法(粒子群算法)对该系统中的跨季节储热系统关键设备(储热水箱和基岩储热设备)的容量进行优化,得出了其最佳的容量配置。     

Effects of Large-Scale Twin Tunnel Excavation on an Existing Pile Group: Three-Dimensional Centrifuge Modeling

Soil Mechanics and Foundation Engineering - Existing piles are commonly encountered during tunnel construction in congested underground areas. Tunnel-soil-pile interaction has recently attracted...     

城市环境敏感地段的“建筑·交通一体化”设计策略初探

城市中的大型建设项目往往处于重要交通节点或多种功能高密度集中的地段,此类地段可称为"环境敏感地段"。在地段内进行建设项目的设计与评价时,需要将"交通"作为内在要素之一纳入建筑设计的范畴综合考虑,实现建筑与步行、轨道、机动车等多种交通系统的整合。以提升城市品质为目标,提出了"建筑·交通一体化"的综合设计策略。     

Bio-diatomite dynamic membrane reactor for micro-polluted surface water treatment

This work investigated the feasibility of treating micro-polluted surface water for drinking water production with a bio-diatomite dynamic membrane reactor (BDDMR) at lab-scale in continuous-flow mode. Results indicate that the BDDMR was effective in removing COD_Mn, DOC, UV₂₅₄, NH₃-N and trihalomethanes' formation potential (THMFP) at a hydraulic retention time (HRT) of 3.5 h due to its high concentrations of mixed liquor suspended solids (MLSS) and mixed liquor volatile suspended solids (MLVSS). The removal of pollutants was mainly ascribed to microbial degradation in BDDMR because the dynamic membrane alone was much less effective in pollutant removal. Though the diatomite particles (5-20 μm) were much smaller in size than the aperture of the stainless steel support mesh (74 μm), microorganisms and their extracellular polymer substances could bind these particles tightly to form bio-diatomite particles which were completely retained by the support mesh. The analysis of molecular weight (MW) distribution by gel permeation chromatography (GPC) shows that the BDDMR could effectively remove the hydrophilic fraction of dissolved organic materials present in the raw water.