Low-loss high power RF switching using multifinger AlGaN/GaN MOSHFETs

We demonstrate a novel RF switch based on a multifinger AlGaN/GaN MOSHFET. Record high saturation current and breakdown voltage, extremely low gate leakage current and low gate capacitance of the III-N MOSHFETs make them excellent active elements for RF switching. Using a single element test circuit with 1-mm wide multifinger MOSHFET we achieved 0.27 dB insertion loss and more than 40 dB isolation. These parameters can be further improved by impedance matching and by using submicron gate devices. The maximum switching power extrapolated from the results for 1A/mm 100 /spl mu/m wide device exceeds 40 W for a 1-mm wide 2-A/mm MOSHFET.     

臭氧法水处理在空调冷却水系统中的应用

探讨了臭氧法杀菌灭藻，缓蚀，阻垢的机理，认为臭氧法可用于空调冷却水处理，并给出在工程设计中的应用方法。     

加氢催化剂器外再生技术(HCRT)的开发与应用

淄博恒基化工有限公司开发的加氢催化剂器外再生技术 (HCRT) ,具有工艺合理、再生催化剂物性恢复好、活性损失少等特点 ,该技术已达到国外器外再生技术的水平。近年来已再生全国 19个炼油厂、2 3个品种的催化剂 12 95t,工业应用均取得满意结果     

多功能DBHTV传输短节的设计与开发

简要介绍了多功能井下超声成像测井仪的总体构思，然后较详细地阐述了其中的一个关键部分-传输短节的设计与开发过程。在短节中应用了单片机系统和FPGA技术，实现了一种包括大数据量井下超声成像测井仪在组合测井新方法，为今后井下超声成像测井仪的发展拓宽了道路。     

日本工业标准 JIS B 4623-1998 钢丝钳

序言本标准是以备注中所示的国际标准为基础,在正文中规定了原日本工业标准中规定的种类、等级和形状、尺寸、品质、检查、产品的称谓及标准,规定了没有变更技术性内容的日本工业标准.但是,在对应的国际标准中没有的项目(检查、产品的称谓及标注),在日本工业标准中进行了补充.     

AN EXTENDED MODELING OF TIDE-WAVE MOTION

1 .　ＩＮＴＲＯＤＵＣＴＩＯＮＴｏｓｔｕｄｙｔｈｅｍｏｔｉｏｎｏｆｔｈｅｔｉｄｅ ｗａｖｅｓ,ｔｈｅｓｈａｌｌｏｗｗａｔｅｒｅｑｕａｔｉｏｎｓ ,ｉ.ｅ .ｔｈｅｖｅｒｔｉｃａｌｉｎｔｅｒｇｒａ ｔｉｏｎｏｆｔｈｅｃｏｎｔｉｎｕｉｔｙｅｑｕａｔｉｏｎａｎｄｍｏｍｅｎｔｕｍｅｑｕａ ｔｉｏｎ ,ｉｓｃｏｎｓｉｄｅｒｅｄａｓｔｈｅｇｏｖｅｒｎｉｎｇｅｑｕａｔｉｏｎｓ.Ｂｙａｂｏｖｅｅｑｕａｔｉｏｎｓｔｗｏｅｑｕａｔｉｏｎｓｒｅｌａｔｅｄｔｏｔｈｅｈｏｒｉｚｏｎ ｔａｌｆｌｕｘｏｆｔｈｅｔｉｄｅ ｃｕｒｒｅｎｔｓａ…     

Growth of CeO_2, Y_2O_3 Buffer Layers for YBCO Coated Conductor

~~Growth of CeO_2, Y_2O_3 Buffer Layers for YBCO Coated Conductor     

国产Ru/Al2O3甲烷化催化剂的工业应用与探讨

对国产Ru/Al2O3催化剂研制开发、侧线试验及工业化试用情况进行了探讨,为国产Ru/Al2O3催化剂的推广应用提供了依据.     

Electromagnetic properties of ferroelectric-ferrite ceramic composites

The NiFe₂O₄ and Pb(Zr_0.52Ti_0.48)O₃ ceramic composites are prepared by conventional solid state reaction method. The microstructural and morphological properties of the composites are studied by X-ray diffraction analysis and scanning electron microscopy. Results indicate that the ferrite and piezoelectric phases can co-exist in the composites. The relationship between the dielectric constant and frequency (40 Hz–40 MHz) as well as temperature is also investigated. It is noted that the transition temperature of the composites is about 380 °C. A double electric hysteresis loop is observed in our composites. The magnetic properties are relatively weak according to the magnetic hysteresis loop. With increase in the content of the ferrite phase, the permeability increases. The electromagnetic properties of the as-prepared composites are tunable according to the content of the NiFe₂O₄ phase.