High performance series-resonance energy-recovery circuit for plasma display panel

A new high performance series-resonance energy-recovery circuit (ERC) for a plasma display panel (PDP) is proposed. Two different ERCs are used for both sides of the PDP, and the slow falling and fast rising times are employed. Therefore, it features the zero voltage switching, low electromagnetic interference, low current stress, no severe voltage notch, and high energy-recovery capability.     

中国(大陆)粉末冶金零件行业2004年进展

本文介绍了中国（大陆）粉末冶金零件行业2004年的生产概况与市场动向。阐述了粉末冶金汽车零件的市场动态。分析了中国（大陆）粉末冶金零件行业面临的挑战。介绍了美国APMI International的PMT认证。     

生物脱氮技术处理废水的应用实践

对废水生物脱氮工艺的开工调试进行了分析,通过对污泥的培养、驯化、使活性污泥达到最佳的污水处理状态。对在调试过程中出现的问题提出相应的改进措施,进一步降低了外排水生化指标。     

级数sum from n=1 to ∞(α(α-1)…(α-n+1)x~n/n!)在x=±1处的敛散性研究

用比较原则及莱布尼兹判别法对函数f(x)=(1+x)α的马克劳林级数在x=±1的敛散情形给予讨论.     

Dynamic deformation behavior of ultrafine-grained low-carbon steels fabricated by equal-channel angular pressing

The dynamic deformation behavior of ultrafine-grained low-carbon steels fabricated by equal-channel angular pressing (ECAP) was investigated in this study. Dynamic torsional tests, using a torsional Kolsky bar, were conducted on four steel specimens, two of which were annealed at 480 °C after ECAP, and then the test data were compared in terms of microstructures, tensile properties, and adiabatic shear-band formation. The equal-channel angular pressed specimen consisted of very fine, equiaxed grains of 0.2 to 0.3 μm in size, which were slightly coarsened after annealing. The dynamic torsional test results indicated that maximum shear stress decreased with increasing annealing time, whereas fracture shear strain increased. Some adiabatic shear bands were observed at the gage center of the dynamically deformed torsional specimen. Their width was smaller in the equal-channel angular pressed specimen than in the 1-hour-annealed specimen, but they were not found in the 24-hour-annealed specimen. Ultrafine, equiaxed grains of 0.05 to 0.2 μm in size were formed inside the adiabatic shear band, and their boundaries had characteristics of high-angle grain boundaries. These phenomena were explained by dynamic recrystallization due to a highly localized plastic strain and temperature rise during dynamic deformation.     

Effect of Hot Band Annealing on Magnetic Properties in 3% Si Grain‐oriented Electrical Steels

Hot band annealing is known to be a prerequisite for good magnetic properties irrespective of manufacturing methods in grain‐oriented Fe‐3 wt.% Si electrical steels. In this study, the effects of hot band annealing on magnetic properties were investigated in 3% grain‐oriented electrical steels of low soluble AI contents and one‐stage cold rolling. Microstructure and precipitate distribution were compared with hot band annealing conditions. Secondary recrystallization behaviour with hot band annealing condition was also discussed.     

焚烧炉烟气中铅、锌、苯并(a)芘的测定

建立了用电感耦合等离子体光谱法(ICP-AES)和高效液相色谱法(HPLC)分别测定焚烧炉烟气中铅(Pb)、锌(Zn)和苯并(a)芘(BaP)的分析方法。研究了烟尘及玻璃纤维滤筒的预处理，测定Pb、Zn、BaP时基体的干扰与消除，并给出Pb、Zn的干扰校正系数。实验测得Pb、Zn和BaP的回收率超过84％，相对标准偏差Pb为3．51％，Zn为7．28%，BaP为4．30％。实验结果表明，该分析方法可以满足焚烧炉运行中的监测需要．     

创新教学管理 提高教学质量

创新教学管理,提高教学质量,需要树立全新的教学管理理念,创新教学管理的运行机制,建立一支能够适应现代大学发展要求的高素质教学管理队伍。     

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。