A method to improve the surge current capability of silicon carbide(SiC)merged PiN Schottky(MPS)diodes is presented and investigated via three-dimensional electro-thermal simulations.When compared with a conventional ...A method to improve the surge current capability of silicon carbide(SiC)merged PiN Schottky(MPS)diodes is presented and investigated via three-dimensional electro-thermal simulations.When compared with a conventional MPS diode,the proposed structure has a more uniform current distribution during bipolar conduction due to the help of the continuous P+surface,which can avoid the formation of local hotspots during the surge process.The Silvaco simulation results show that the proposed structure has a 20.29%higher surge capability and a 15.06%higher surge energy compared with a conventional MPS diode.The bipolar on-state voltage of the proposed structure is 4.69 V,which is 56.29%lower than that of a conventional MPS diode,enabling the device to enter the bipolar mode earlier during the surge process.Furthermore,the proposed structure can suppress the occurrence of‘snapback'phenomena when switching from the unipolar to the bipolar operation mode.In addition,an analysis of the surge process of MPS diodes is carried out in detail.展开更多
目的系统性评价静脉注射硝普钠(SNP)治疗精神分裂症(SZ)的有效性。方法通过PubMed、Web of Science、EMbase、Cochrane Library等英文数据,以及中国生物医学文献数据库、维普、万方和中国知网等中文数据库,检索有关静脉注射硝普钠治疗...目的系统性评价静脉注射硝普钠(SNP)治疗精神分裂症(SZ)的有效性。方法通过PubMed、Web of Science、EMbase、Cochrane Library等英文数据,以及中国生物医学文献数据库、维普、万方和中国知网等中文数据库,检索有关静脉注射硝普钠治疗精神分裂症的随机对照试验,所有数据库检索时限均于2020年11月7日截止。筛选文献、提取数据后,采用Review Manager 5.3软件进行Meta分析。结果最终纳入4个随机对照试验,共134例患者,结果显示,SNP组与对照组PANSS一般精神病理量表评分[MD=0.05(95%CI:-2.63,2.73),P>0.05]、PANSS阳性量表评分[MD=-0.76(95%CI:-1.74,0.23),P>0.05]、PANSS阴性量表评分[MD=-1.77(95%CI:-5.28,1.74),P>0.05]比较均无差异。敏感性分析后,SNP组与对照组PANSS阴性量表评分比较无差异[MD=-0.19(95%CI:-1.62,1.25),P>0.05]。SNP组与对照组BPRS-18量表评分比较有差异[MD=-5.91(95%CI:-11.42,-0.41),P<0.05],但异质性较高(I2=54%)。结论SZ患者对SNP耐受性较好,但与安慰剂比较,笔者无法得出SNP能够改善SZ相关精神症状的结论。展开更多
基金the National Research and Development Program for Major Research Instruments of China(Grant No.62027814)the National Natural Science Foundation of China(Grant No.61904045)Zhejiang Provincial Natural Science Foundation of China(Grant No.LQ20F040004)。
文摘A method to improve the surge current capability of silicon carbide(SiC)merged PiN Schottky(MPS)diodes is presented and investigated via three-dimensional electro-thermal simulations.When compared with a conventional MPS diode,the proposed structure has a more uniform current distribution during bipolar conduction due to the help of the continuous P+surface,which can avoid the formation of local hotspots during the surge process.The Silvaco simulation results show that the proposed structure has a 20.29%higher surge capability and a 15.06%higher surge energy compared with a conventional MPS diode.The bipolar on-state voltage of the proposed structure is 4.69 V,which is 56.29%lower than that of a conventional MPS diode,enabling the device to enter the bipolar mode earlier during the surge process.Furthermore,the proposed structure can suppress the occurrence of‘snapback'phenomena when switching from the unipolar to the bipolar operation mode.In addition,an analysis of the surge process of MPS diodes is carried out in detail.
