金属基复合材料界面层阻尼功能研究

采用CVD技术制备了具有不同界面层的C-f/Al金属基复合材料，获得了一种界面层阻尼功能设计的新方法. 研究发现具有特殊界面层的C-f/Al复合材料的抗拉强度、弹性模量和阻尼性能比无界面层时都有明显增加，并且不同界面层的效果不同. 碳层对复合材料阻尼性能的提高效果最大，硅层的提高效果不如碳层，碳硅混合层的效果居中. 涂层的厚度也影响了阻尼提高的效果，较厚的碳层效果更好，这是由于提高了复合材料的阻尼应变振幅效应而产生的. 研究认为发生在界面层的微滑移是其主要的阻尼机制.     

Leaning Towards Agile in 21~(st) Century

Background: During the last fifteen years there ha s been an increased drive for organisations to reduce costs. From a production po int, this has often centred on lean manufacturing and JIT waste elimination proc esses. However, in 1991, the Iaccocca Institute Bethlehem P.A commissioned a re port specifically to analyse the changing nature of the marketplace. As a result , in the following year, the Agile Manufacturing Forum was initiated and the ter m ‘agile or responsive manufacturing‘ was first intr...     

采用交流能源的低功耗DCVSL电路研究

从改变CMOS电路中能量转换模式的观点出发，研究利用渐变功率时钟的低功耗CMOS电路设计. 首先讨论钟控功率信号的代数表示及有关性质，然后归纳采用直流能源的互补CMOS逻辑门转化为采用交流能源的钟控CMOS门电路的设计过程. 在此基础上进一步提出采用交流能源的DCVSL电路设计. 采用正弦功率时钟的PSPICE模拟证实了钟控DCVSL电路具有正确的逻辑功能及低功耗工作的特点. 最后提出了一种将钟控信号转换为标准CMOS逻辑电平的接口电路并用计算机模拟验证了它的有效性.     

Comparative study of the karyotypes of two Egyptian species of bats,Taphozous perforatus andTaphozous nudiventris (Chiroptera: Mammalia)

A detailed karyotypic analysis of two Egyptian species of bats,Taphozous perforatus andTaphozous nudiventris, was made on the basis of conventional data and G-band patterns. No detectable karyotypic difference was found between the two species (2n=42, F.N. 64). By comparison of G-band patterns, some differences between the two species were seen in the corresponding autosomal pairs. These results are reported for the first time in Egypt.     

砂轮平衡精度对工件表面粗糙度影响的研究

对砂轮平衡精度与磨削加工工件表面粗糙度之间关系作了研究 ,通过理论与实验 ,给出了砂轮不平衡量与工件表面粗糙度关系式。为砂轮在线液体平衡的方法减小砂轮表面粗糙值提供了理论与实践依据     

无格式设计观

当 Kjell Ekhorn 还在学校学习图形设计,Jon Forss 已在这个行业里工作了不少年头。1989年 Jon Forss 于1LeicesterPolytechnic 毕业后就在 Bath 为一家广告代理商工作,四年之后他移居伦敦为 namara 设计公司设计图书封面。五年以后,他遇到从伦敦 Centrl St.Martins 学校毕业不过两年,正以自由职业者身份从事图书封面设计、图片制作和摄影工作的 Kjell Ekhorn。两人惊讶于互相对图书封面设计的看法,一时相见恨晚,然后自然而然的开始了两人合作的NON-FORMAT 时代。     

Decision trees for forecasting

Recent years have seen an increasing cross-fertilization between the fields of decision analysis and forecasting. Decision-analytic models often require forecasts as inputs, and aspects of the Bayesian decision-theoretic framework underlying decision analysis have proved useful to forecasting, particularly in contexts where subjective judgemental inputs are required. This paper describes the use of decision tree analysis for forecasting and illustrates its use for corporate divisional forecasting and planning. A specialized decision-analytic technique, acts as events, is also described and illustrated to forecast a new product's earnings. Conclusions are drawn about the applicability of decision analysis for forecasting.     

Indoxyl derivatives of drug metabolites

Summary Indoxyl derivatives were detected as minor products among the urinary metabolites of two trial drugs, a benzodiazepine (GP 55 129) and a benzophenone (CGP 11 952). Their structures were elucidated by NMR and mass spectroscopy. Presumably, metabolites containing potential aldehyde functions react spontaneously with endogenous indoxyl. Such derivatives have not hitherto been encountered in drug metabolism.     

芦岭矿采空区煤炭自燃发火与开采技术关系的试验研究

采用了包括多点热电偶测定采空区遗煤温度、应用六氟化硫气体示踪和测定漏风压差等综合技术手段研究分析了漏风分布规律。结果发现,遗煤温度变化受漏风温度和漏风强度影响较大;停采线漏风的量及漏风时间受主要进、回风道的布置以及采掘接替安排的影响。由于采用无煤柱开采技术,三个相邻阶段的采空区之间连通,存在漏风,最后又从开采技术上提出了防火措施。