简介:Thetitlecomplex[NH_3CH_2CH(NH_2)CH_3]_2[M(Ⅵ)O_2(OC_6H_4O)_2](M=Mo_(0.6)W_(0.4))wassynthesizedviaasimplesolution-phasechemicalroute.ThedeterminationofsinglecrystalX-raydiffractionrevealedthatthetitlecompoundiscrystallizedinamonoclinicsystemwithP2(1)/nspacegroup,a=1.0913(10)nm,b=1.0442(10)nm,c=1.8842(19)nm,α=90°,β=96.530(17)°,γ=90°,Z=4,andV=2.133(4)nm3.Themononuclearanionicunit[M(Ⅵ)O2(OC6H4O)2]2-displayschiralpseudo-octahedral[MO_6]coordinationgeometryandislinkedbychiralcationsviahydrogenbondandπ…πstackinginteraction.Thetransmissionelectronmicroscopyimagesshowthatthetitlecomplexiscomprisedofnano-particleswithdiametersrangingfrom20to50nm.TheNMRstudyshowsthe1Hdownfieldchemicalshiftsof[NH_3CHaHbCH(NH_2)CH_3]+cationsinthetitlecomplexwhenitismixedwithadenosine-triphosphate(ATP),andthechemicalshiftdifferencebetweenHaandHbisincreasedgreatly,andmostofthecatecholateligandsdissociatefromthecentralmetalatoms.TheDNAcleavageactivityexperimentrevealsthatDNAcleavagepromotedbythetitlecomplexislowerthanthatbyNa_2MoO_4whichpossessesantitumorpro-perty,buthigherthanthatbyNa_2WO_4.
简介:Lactivicin,anovelinhibitorofbacterialcellwallsynthesis,wasisolatedfromtheculturefil-tratesofmicroorganismYK-258andYK-422.Itexhibitsbiologicalactivitiessimilartothoseoftheβ-lactamantibiotics,althoughitdoesnothaveaβ-lactamringinitsmolecule.Sincethediscoveryoflactivicin,hundredsofitsderivativeshavebeensynthesized.Most
简介:Thispaperreportsthattheetchingmorphologyofdislocationsin8°off-axis4H-SiCepilayerisobservedbyusingascanningelectronicmicroscope.Itisfoundthatdifferenttypesofdislocationscorrespondwithdifferentdensitiesandbasalplanedislcation(BPD)arrayandthreadingedgedislocation(TED)pileupgroupliealongsomecertaincrystaldirectionsintheepilayer.Itisconcludedthattheelasticenergyofthreadingscrewdislocations(TSDs)ishighestandTEDsislowestamongthesedislocations,sothedensityofTSDsislowerthanTEDs.TheBPDscanconverttoTEDsbutTSDscanonlypropagateintotheepilyerinspiteofthehigherelasticenergythanTEDs.ThereasonoftheformofBPDsarrayinepilayeristhatthebigstepalongthebasalplanecausedbyfacedefectsblockedtheupstreamatoms,andTEDspileupgroupisthatthedislocationsslideisblockedbydislocationgroupsinepilayer.
简介:与飘移散开(DD)的联合使用模型,试验性的测量参数和小信号的正弦曲线不变的分析,我们为4H-SiC提取Y参数埋葬隧道的金属氧化物半导体域效果晶体管(BCMOSFET)。输出电线走火水流获得G,梅森的不变的U分别地在普通来源的配置f(T)和摆动f(最大)的最大的频率为外推的统一水流获得频率被计算。这里f(T)=800MHz和f(最大)=5GHz为4H-SiCBCMOSFET被提取,当地效果活动性到达它的山峰时,珍视87cm(2)/Vs什么时候V-GS=4.5V。模拟结果清楚地证明4H-SiCBCMOSFET和地效果活动性的典型频率是优异的,由于新奇结构,与常规MOSFET相比。
简介:研究了辐照对4H-SiC纵向双注入金属氧化物场效应晶体管(VDMOS)电学参数的影响.通过SRIM和SILVACO软件仿真,观察到器件不同区域引入损伤后电学参数的漂移.仿真结果表明,不同区域的损伤会造成器件电学参数不同的退化.器件JFET区的非电离损伤会使器件的导通电阻增大,而靠近碰撞电离中心的非电离损伤会使器件的击穿电压增大.辐照在器件界面处引入的正电荷或负电荷同样会对器件的电学参数带来很大的影响.沟道上方SiC/SiO2界面处的正电荷会导致器件的阈值电压、导通电阻以及击穿电压降低,而终端区主结上方的SiC/Metal界面处的正电荷只会导致击穿电压的降低.相反,沟道上方SiC/SiO2界面处的负电荷会导致器件的阈值电压、导通电阻以及击穿电压增加.
简介:Treatmentof4-amino-3-(1-aryl-5-methyl-1,2,3-triazol-4-yl)-5-mercapto-1,2,4-triazoles/2-amino-5-(1-aryl-5-methyl-1,2,3-triazole-4-yl)-1,3,4-thiadiazoleswithbenzaldehyde,acetoneandω-bromoacetophenonewastestedandcompared.ThetitlecompoundsSchiffbases,amides,imidazolo[2,1-b]-1,3,4-thiadiazolesand7H-s-triazolo[3,4-b]-1,3,4-thiadiazineshavebeenconfirmedbyelementalanalyses,^1HNMR,IRandMSspectra.AllthecompoundshavealsobeenscreenedfortheirantibacterialactivitiesagainstB.subtilis,S.aureusandE.coli.