Development of grain boundary allotriomorphic ferrite/granular bainite duplex steel

A new hot-rolled low alloy high strength steel with grain boundary allotriomorphic ferrite/granular bainite duplex micro-structure has been developed through novel microstructure and alloying designs without any noble metal elements such as nickel and molybdenum. Its as-rolled microstructure and mechanical properties, fatigue crack propagation behavior compared with single granular bainitic steel as well as continuous cooling transformation, were investigated in detail. The measured result of CCT (continuous cooling transformation) curve shows that such duplex microstructure can be easily obtained within a wide air-cooling rate range. More importantly, this duplex microstructure has much better combination of toughness and strength than the single granular bainite microstructure. It is found that the grain boundary allotriomorphic ferrite in this duplex microstructure can blunt the rni-crocrack tip, cause fatigue crack propagation route branching and curving, and thus it increases the resistance to fati     

Modification of High Performances of Polymer Cement Concrete

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SABUL: A Transport Protocol for Grid Computing

This paper describes SABUL, an application-level data transfer protocol for data-intensive applications over high bandwidth-delay product networks. SABUL is designed for reliability, high performance, fairness and stability. It uses UDP to transfer data and TCP to return control messages. A rate-based congestion control that tunes the inter-packet transmission time helps achieve both efficiency and fairness. In order to remove the fairness bias between flows with different network delays, SABUL adjusts its sending rate at uniform intervals, instead of at intervals determined by round trip time. This protocol has demonstrated its efficiency and fairness in both experimental and practical applications. SABUL has been implemented as an open source C++ library, which has been successfully used in several Grid computing applications.     

High Order Finite Difference Approximations of Electromagnetic Wave Propagation Close to Material Discontinuities

Electromagnetic wave propagation close to a material discontinuity is simulated by using summation by part operators of second, fourth and sixth order accuracy. The interface conditions at the discontinuity are imposed by the simultaneous approximation term procedure. Stability is shown and the order of accuracy is verified numerically.     

多通道同步高速数据采集系统研制

介绍了一个最高采样率为100MHz，采样精度为8bit，基于PCI总线和计算机并口的8通道同步高速数据采集系统的设计，整套系统具有同步误差小、触发方式多样、操作灵活等特点。     

我国城乡居民照明用电状况调查分析

本文介绍了一次全国性的居民家庭照明用电抽样调查研究案例，全面而系统地分析了我国城乡居民家庭照明用电情况和各类照明光源在居民家庭中的使用状况。     

提高200MW机组高压加热器投入率的研究

通过对武汉钢电股份有限公司2台200MW机组2年来高压加热器运行状况的统计分析，找出影响高加投入率的主要原因，提出相应的技术改造和技术措施，大大提高了高加投入率。     

高强混凝土T形截面双向压弯构件承载力的研究

对9根T形截面高强混凝土双向压弯构件进行试验研究,揭示了这类构件的破坏形态,并进一步分析T形截面正截面承载力的变化规律.     

高纯金属与聚合物膜pH电极的研制

介绍以纯金属为基体,PVC为载体,α-萘胺为活性物质,三氯甲烷为溶剂研制成的聚合物膜电极,将它用于测定溶液的pH,取得了一些成效。     

材料韧性断裂的细观力学分析与测试

应用细观力学的观点分析材料韧性断裂方面的独到之处及便利，并结合高强铸铁细观力学的断裂判据——临界空穴扩张比的测试研究，介绍了作者在应用细观力学研究高强铸铁韧性断裂方面所做的工作及进展