Effects of crystallization temperature on phase evolution and energy storage properties of BaO-Na2O-Nb2O5-SiO2-Al2O3 glass-ceramics

Barium sodium niobate (BNN) glass ceramics were successfully fabricated with controllable crystallization by technology for heating processing and the effects of crystallization temperatures on phase evolution, microstructure, dielectric properties and breakdown strength were investigated systematically. In addition, the empirical power-law dependence of breakdown strength on thickness ($E_b\propto d^{-n}$) was confirmed in BNN glass-ceramic system with an exponent n of 0.21. Based on the results, the BNN glass ceramic crystallized at 800?°C presents a remarkable breakdown strength (BDS) of 2322?kV/cm with the tested thickness of 30?μm, and the highest energy density of 16.6?J/cm³ was achieved.     

阶梯掺杂P柱区二维类超结LDMOS的研究

提出了一种阶梯掺杂P柱区二维类超结LDMOS结构。漂移区采用P/N柱交替掺杂的方式形成纵向类超结。漂移区的P柱采用掺杂浓度从源端到漏端逐渐变低的变掺杂结构。这种变掺杂P柱区的引入对衬底辅助耗尽效应所带来的电荷不平衡问题进行了调制,使得漂移区可以充分耗尽,提高了耐压。P区变掺杂可以提高N区浓度,降低了导通电阻。与常规二维类超结LDMOS结构相比,击穿电压提高了30%,导通电阻下降了10.5%,FOM提升了87.6%,实现了击穿电压与导通电阻的良好折中。     

一种电场调制载流子存储槽栅双极型晶体管

提出了一种性能优良的电场调制载流子存储槽栅双极型晶体管(CSTBT)。结合电场调制原理,在器件的载流子存储(CS)层引入P掺杂条,改善器件栅极下方氧化硅拐角处的电场分布,防止器件提前发生雪崩击穿,提高了器件的击穿电压。器件处于关断状态时,内部大量的空穴载流子通过CS层中未完全耗尽的P掺杂条到达发射极,抑制了CS层阻挡空穴的作用,有效提高了器件的关断速度。与传统CSTBT器件相比,改进器件的击穿电压值提高了379 V,关断时间缩短了19.1%,器件性能大幅提高。     

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。     

大庆油田弱碱三元复合驱采出液电脱水性质研究

为确定弱碱三元复合驱采出液处理技术,进行了弱碱三元复合驱采出液电脱水性质研究。利用电导率测定仪、原油智能脱水试验仪、原油介电强度自动测试仪等仪器测定弱碱三元复合驱采出液电导率、含水率、击穿场强。结果表明:弱碱三元复合驱采出液电导率测试值约在4×10~3~2×10~4μs/cm之间;在保证原油含水达标合理的情况下电场强度为1 400~1 700 V/cm,电脱时间为60~90 min;影响击穿场强主要因素是含水量、活性剂含量,其次是温度。     

All-organic Poly(butyl methacrylate)/Poly(vinylidenefluoride-trifluoroethylene) Dielectric Composites with Higher Permittivity and Low Dielectric Loss for Energy Storage Application

With the rapid development of electronic industry and technology, there are increasingly stringent requirements on dielectric materials with higher permittivity, lower loss, and enhanced breakdown field. Since single dielectric material cannot meet the demands of industrialization, polymer-based dielectric materials with better quality have been widely applied. This study focused on a poly(butyl methacrylate/poly(vinylidene fluoride-trifluoroethylene) dielectric composite thin film, which were prepared by solution casting method. X-ray diffraction and differential scanning calorimetry data indicated that introducing poly(butyl methacrylate) led to increase in the crystallinity. The result of scanning electron microscopy showed the good compatibility between poly(vinylidene fluoride-trifluoroethylene) and poly(butyl methacrylate). Besides, the dielectric film remained good mechanical property. The dielectric properties were studied as a function of filler content and frequency. The results showed that the permittivity was as high as 13.3, while the breakdown field was 322?MV m^?1 when the fraction of poly(butyl methacrylate) was 10%. Blending poly(butyl methacrylate) improved the dielectric performance of the poly(vinylidene fluoride-trifluoroethylene).     

Material dependent dielectric breakdown model

Dielectric breakdown in ceramics and composites has previously been determined by the dielectric breakdown model, dependent only on the electric field strength at a certain point and intermolecular distance in a lattice. This does not take into account quantum aspects of the lattice structure into account. The present model takes into account quantum variations of particles in conjunction with different particle characteristics. Dielectric breakdown patterns are characterised by their quantum breakdown probabilities and studies are carried out as a function of the applied electric field, temperature and specific material constants responsible for breakdown, such as the mean free path and the potential barrier present.     

关于影响变压器外绝缘距离因素的研究

不同方式的试验电压下,对空气间隙击穿电压与间隙距离相互关系进行分析,探讨试验电压对变压器外绝缘距离的影响,并分析了气候条件、海拔高度及污秽程度对变压器外绝缘的影响。     

KJC－2型矿山机械工程检修车

ＫＪＣ－２型矿山机械工程检修车是集机械设备状态监测与故障诊断研究实验室和修理车间两大功能于一体的大型自行式设备．本文介绍其基本结构与装备、性能参数、适用范围和使用条件．     

堵水调剖用暂堵剂ZDJ-98的研制与性能评价

本文简述了暂堵剂在多孔介质中的 堵原理,研究了暂堵剂ＺＤＪ－９８的配方及性能。结果表明,该暂堵剂成胶,破胶反应速度可控制,在６０－８０℃地层条件下形成的弱凝胶对中低渗透层能形成有效的堵塞,弱凝胶破胶液化反渗透率可恢复至８０％以上。