整体毡纤维体积分数对CVD增密的影响

将3组不同纤维体积分数的整体毡采用等温CVD进行沉积热解炭增密,结合CVD沉积过程中整体毡内气体传质数学模型,研究了整体毡的纤维体积分数对CVD增密过程的影响,研究结果表明:纤维体积低的整体毡沉积时增重率高;纤维体积分数高的整体毡容易获得较高密度的C/C复合材料;纤维体积分数超过35％的整体毡经过300 h的化学气相沉积,坯体的体积密度能达到1.52 g/cm~3。     

GB/T5213-2001深冲压用冷轧薄钢板及钢带标准述评

介绍了标准编制的技术工作及内容 ,简述标准修订的创新点及应用推广、实施效益情况。     

CpTi(dbm)Cl_2催化烯烃聚合及其聚合物性质

开发了一种新型非茂聚烯烃催化剂———CpTi(dbm)Cl2,考察了催化剂在均相及负载条件下对乙烯及乙烯-1-己烯共聚的催化行为。催化剂在均相条件下对乙烯聚合的催化活性较低,但用MgCl2和MgCl2/SiO2复合双载体对催化剂进行负载后,催化乙烯聚合具有非常好的催化活性。催化剂还具有良好的共聚能力及良好的氢调敏感性。     

The long string as a field probe

We show how a long string can be used to probe the incident field across the target zone of a radar cross section (RCS) test range. The string may be stretched horizontally from wall to wall, or vertically from floor to ceiling. One end of the string is fixed and the other end is moved by an actuator mounted in the wall or ceiling. The resulting motion changes the angle of the string with respect to the incident-field direction, during which time the coherent radar echo is recorded as a function of the string angle. The coherent signal-as-a-function-of-angle data are then transformed to the cross-range domain using the fast Fourier transform (FFT), whence we obtain a chart of the incident field amplitude as a function of cross-range distance. Numerical examples are presented that show how variations in the incident field influence the string echo. A sample of experimental data shows that the processed data are readily interpreted.     

A high-resolution burst-mode laser transmitter with fast and accurate level monitoring for 1.25 Gb/s upstream GPONs

An innovative burst-mode laser transmitter (BM-TX) is presented for gigabit-capable passive optical network (GPON) upstream transmission at 1.25 Gb/s. The laser bias and modulation current each can reach 80 mA with a resolution of 0.1 mA providing a total drive current up to 160 mA. Both currents are generated by 10-bit current steering digital-to-analog converters (DACs), the architecture of which is specially adapted to yield a monotonic current setting at settling times below 12.8 ns. Tests show that fast automatic power control (APC) can stabilize and track the launched optical power with a tolerance of less than 1 dB over a wide temperature range for outdoor operation. The APC only requires a straightforward calibration of the "0" and the "1" level at room temperature. Optical level monitoring on strings of four consecutive "0" bytes and two consecutive "1" bytes at 1.25 Gb/s is demonstrated. APC based on such short strings of data has not been shown before. The circuits have been designed in a 0.35 /spl mu/m SiGe BiCMOS process. Experimental results show that this dc-coupled BM-TX meets the specifications of the recently approved ITU-T Recommendation G.984.2 supporting an intelligent power leveling mechanism (PLM).     

添加VC的TiB2基硬质材料研究

对添加VC的TiB2基硬质材料进行了研究。通过实验测定了硬度、横向断裂强度、高温强度以及耐磨性等性能，通过观察SEM照片研究了VC对TiB2基硬质材料组织结构的影响。综合各种指标，我们确定在TiB2-Fe—Mo硬质材料中VC的最佳添加量为0．5％。     

汽车空调制冷系统中应用R407C的分析

本文对混合工质R407C与R12的物理和热力性质进行了比较分析，并针对汽车空调制冷系统的特点，对两种工质在变工况下进行了制冷系统的理论循环分析，阐明了在汽车空调制冷系统中使用R407C的可行性。     

成都市火车南站斜拉桥斜拉索安装工艺

采用倒链葫芦、卷扬机或软牵引装置对斜拉索进行牵引安装 ,使牵引力达到 5 0 0余kN ,解决了斜拉索安装拉力大这一施工难题。     

电能替代与营销传统业务深度融合的实践

为贯彻落实"以电代煤、以电代油、电从远方来"的电能替代发展战略,苏州供电公司推动政府出台电能替代相关政策,对内完善营销系统流程,进一步明确工作职责,规范项目管理,明晰工作流程,开展培训考核,加强风险控制,逐步实现能效和电能替代工作与业扩报装、客户服务等营销传统业务的深度融合,提高了专业管理流程的精益度、精准性,获得了客户和市场的较好响应效果。