输尿管镜气压弹道碎石术严重并发症的防治

目的探讨输尿管镜气压弹道碎石严重并发症与预防措施。方法总结分析输尿管镜气压弹道碎石治疗患者的资料,统计并发症的发生和处理情况。结果输尿管穿孔3例,输尿管口损伤2例,输尿管黏膜下假道形成3例,输尿管断裂1例,输尿管全层黏膜撕脱1例。结论输尿管镜下取石术并发症的发生与手术者的技术操作密切相关,正确熟练地操作可有效减少并发症。     

生物安全实验室工程施工中应注意的问题

简要介绍了生物安全实验室的分级,就生物安全实验室施工中可能存在的某些问题进行探讨,供准备建造生物安全实验室的单位及施工单位参考.     

Excitation of hypersound in n-GaN films

The aim of this paper is the analysis of hypersound excitation in GaN films. Simulation of process is presented for a case of a thin film geometry on a non-piezoelectric substrate. The frequency range considered is from 50 GHz up to 200 GHz. The excitation is due to coupling with space charge waves (SCWs) in GaN film. The amplification of SCWs is related with negative differential conductivity in GaN films. Possible spatial increments are obtained. The amplified SCWs can excite hypersonic waves at the same frequency due to piezoeffect and deformation potential mechanisms. The first effect is stronger and causes an effective resonant excitation of hypersonic waves in the case of full mechanic contact of GaN film and non-piezoelectric substrate.     

GaAs/AlAs短周期超晶格的静压光致发光研究

在室温和液氮温度下对不同层厚的GaAs/AlAs短周期超晶格在0—50kbar范围内进行了静压光致发光研究。在导带最低能级为类Γ态能级(Ⅰ类超晶格)和类X态能级(Ⅱ类超晶格)两种情况下都得到了类Γ态能级与类X态能级差随层厚的变化。首次直接观察到室温、常压下(GaAs)_(11)(AlAs)_(11)超晶格中类Γ态能级与类X态能级发生交叉。从发光峰的强度随压力的变化求得室温下在类Γ态能级与类X态能级恰好交叉的压力下类X态电子和类Γ态电子到价带空穴的跃迁几率之比从(GaAs)_(17)(AlAs)_(17)的1.4×10~(-4)逐渐增加到(GaAs)_6(AlAs)_6的4.6×10~(-3)。表明类Γ态和类X态间的混合较弱。对实验结果进行了简短的讨论。     

Spin-filter silicene devices induced by asymmetric electrodes

Using nonequilibrium Green's function in combination with the density functional theory, we investigate the spin-dependent transport properties of three silicene-based heterojunctions. The calculated results show that the heterojunctions are promising multifunctional devices in spintronics due to their nearly perfect bipolar spin-filter effect and high rectification ratio. Also shown are the obvious negative differential resistance behaviors for both spin channels. By analyzing the spin-resolved transmission spectra and the band structure of ZSiNR electrodes, as well as the spatial resolved local density of states, the mechanisms for these intriguing properties are demonstrated in detail.     

基于阳极弱反型层消除负阻效应的新型SOI LIGBT

在SOI衬底上,制作了一种基于阳极弱反型层消除负阻效应的新型横向绝缘栅双极晶体管(SOI AWIL-LIGBT)。利用反型所形成的高阻值电阻来使PN结阳极快速导通,阳极P+区中的空穴可以更快地注入漂移区,从而消除负阻效应。仿真结果表明,该新型LTGBT在保证关断速度不变的情况下,击穿电压为307 V(漂移区长度为18 μm)比,比常规SA-LIGBT提升了56%,并消除了负阻效应。     

A New Design Methodology for Time-Based Capacitance-to-Digital Converters (T-CDCs)

This paper introduces a 9-bit time-based capacitance-to-digital converter (T-CDC). This T-CDC adopts a new design methodology for parasitic cancellation with a simple calibration technique. In T-CDCs, the input sensor capacitance is first converted into a delay pulse using a capacitance-to-time converter (CTC) circuit; then this delay signal is converted into a digital code through a time-to-digital converter (TDC) circuit. A prototype of the proposed T-CDC is implemented in UMC 0.13 μm CMOS technology. This T-CDC consumes 8.42 μW and achieves a maximum SNR of 45.14 dB with a conversion time of 1 μs that corresponds to a figure of merit (FoM) of 16.4 fJ/Conv.     

变频器RS-485通讯功能在纺织行业的应用

本文主要介绍了DELIXI变频器RS-485通讯功能在浙江萧山某纺织公司空压机站活塞式空气压缩机（以下简称“空压机”）上的节能改造应用过程和RS-485通讯网络的构成，并且给出了用户在现场遇到的各种难题解决方案。从中叙述了变频器的外围设备对恒压供气系统的传动性能、稳定性、可靠性等质鬣指标所起到的作用，并指出了变频器技术服务的重要性。     

不锈钢压力传感器管座

文章介绍了不锈钢压力传感器管座的关键技术和工艺,对管座设计和工艺过程中易出现的难题进行了分析并给出了实现方法及其结果。这种管座在抵御10000PSI的高压下仍能保证高可靠的密封性能,因而适用性特别强。     

一种多晶硅高温压力传感器

制作压力传感器时，在二氧化硅层上淀积多晶硅膜，既可利用优良的机械特性，又可保证压敏电阻与衬底间具有良好的绝缘性，由此可大大提高器件的温度特性。介绍了一种多晶硅压力传感器的原理和设计。实验结果表明，这类传感器具有灵敏度好，精度高等特点，电路工作范围为０－２５０℃，且具有良好的温度稳定性。