简介:Inthisstudy,inordertoevaluatetheperformanceofhomogenizedbauxite,twoAl_2O_3-SiC-Ccastableswerepreparedusinghomogenizedbauxiteandbrownfusedcorundumasaggregates,respectively.5mass%andalusitewasintroducedintothetwocastablessoastoresearchtheeffectandmechanismofandalusiteinAl_2O_3-SiC-Ccastables.Theresultsshowedthat:(1)comparedwiththebrownfusedcorundumbasedcastables,thehomogenizedbauxitebasedcastableshadhighercoldstrengthafterheattreatment,butlowerhotmodulusofrupture;(2)additionof5mass%andalusitecouldenhancethecoldandhotmodulusofrupture,improvethethermalshockresistance,andoptimizethemicrostructureofspecimens;(3)themullitizationofandalusitewasnotobviousinthecastablesfiredat1100-1400℃.
简介:UnipolarresistiveswitchingbehaviorsoftheZnOandAl2O3/ZnOfilmsfabricatedonflexiblesubstratesbypulselaserdepositionwerestudiedinthispaper.Thefilmsweredepositedatroomtemperaturewithoutpost-annealingtreatmentduringtheprocess.XraydiffractionresultsindicatedthatZnOfilmhasadominantpeakat(002).ScanningelectronmicroscopyobservationshowedacolumnargrainstructureoftheZnOfilmtothesubstrate.ThebilayerdeviceofAl2O3/ZnOfilmshadstableresistiveswitchingbehaviorswithagoodenduranceperformanceofmorethan200cycles,highresistiveswitchingratioofover103atareadvoltageof0.1V,whichisbetterthanthatofthesingleoxidelayerdeviceofZnOfilm.Apossibleresistiveswitchingfilamentarymodewasdemonstratedinthispaper.TheconductionmechanismsofhighandlowresistancestatescanbeexplainedbyspacechargelimitedconductionandOhmic’sbehaviors.Theenduranceofthebilayer(BL)devicewasnotdegradeduponbendingcycles,whichindicatesthepotentialoftheflexibleresistiveswitchingrandomaccessmemoryapplications.
简介:Theneworganic-inorganiccompound,[C_6H_7N_2O_2]_3TeCl_5·2Clwassynthesizedanditsstructurewasdeterminedatroomtemperatureinthetriclinicsystem(P~-1)withthefollowingparameters:a=10.5330(11)?,b=10.6663(11)?,c=15.9751(16)?,α=82.090(2)°,β=71.193(2)°,γ=68.284(2)°andZ=2.ThefinalcycleofrefinementledtoR=0.057andRw=0.149.ThecrystalstructurewasstabilizedbyanextensivenetworkofN--H···Clandnon-classicalC--H···Clhydrogenbondsbetweenthecationandtheanionicgroup.Severalthermalanalysistechniquessuchasthermogravimetricanalysis,differentialscanningcalorimetricanalysisandevolvedgasanalysiswereused.Weusedisoconversionalkineticsmethodstodeterminethekineticsparameters.Weobservethatthedecompositionof[C_6H_7N_2O_2]_3TeCl_5·2Clentailstheformationhydrochloricacidofnitroanilineasvolatiles.Theinfraredspectrawererecordedinthe4000–400cm~(-1)frequencyregion.TheRamanspectrawererecordedintheexternalregionoftheanionicsublatticevibration50–1500cm~(-1).TheopticalbandgapwascalculatedfromtheUV-VisabsorbancespectrausingclassicalTaucrelationwhichwasfoundtobe3.12and3.67eV.
简介:BackgroundTaxifolin(Tax)isanessentialnaturalantioxidant.MultiplestudieshaveshownthatTaxcanprotectcardiomyocytesfromischemia-reperfusioninjury.However,theunderlyingmechanismisstillunclear.MethodsH9C2cellswererandomlydividedintocontrol,H_2O_2group,Taxpretreatmentgroup(Tax+H_2O_2);Taxeffectgroup.CellactivitywasdetectedbyCCK-8andtheintracellularstructurewasobservedbytransmissionelectronmicroscopy.AutophagywasdeterminebyWesternblottinganalysisofBeclin-1,Bcl-2andPKC.ResultsTaxpretreatmentsignificantlyincreasedanti-apoptoticproteinBcl-2andautophagyproteinBeclin-1.ExpressionofPKCwasinhibitedbyTax.ConclusionsTaxpretreatmentcouldprotectH9C2cellsagainstH_2O_2-induceddamagethroughtheBcl-2andautophagypathways.
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简介:摘要随着社会经济不断发展,我国印染行业发展迅速,无论是印染规模还是印染技术,均得到了长足的发展和提高,印染废水产生量日益增多,印染废水污染物组成也愈发复杂,相应提高了对于印染废水回用技术的实际要求。但就我国印染行业当前的印染废水回用现状来看,其废水回用技术仍以传统二级生物处理工艺为主,面对污染物更加复杂、结构更加稳定的现代印染废水,表现出较明显的不适应性和局限性。在这种环境背景下,笔者就A2/O-O3-BAF工艺在印染废水回用中的应用进行了试验探索,试验结果表明,A2/O-O3-BAF工艺可有有效处理印染废水中的复杂污染物,使其达到废水回用相关标准要求,具有较好的经济性和适用性。
简介:TheeffectofAl-3Ti-0.2C-5Sr(wt%)grainrefinerontherefiningperformanceandmodificationofA356alloywasinvestigatedusingopticalmicroscope(OM).ThemorphologyandcrystalstructureofternaryAl-Ti-SrphasesinAl-3Ti-0.2C-5Srrefinerwereanalyzedbyscanningelectronmicroscopy(SEM)andtransmissionelectronmicroscopy(TEM).TheresultsshowthattheternaryAl-TiSrphasesinAl-3Ti-0.2C-5SrrefinercanpromotethegrainrefiningefficiencyofA356alloy.TheternaryAl-Ti-Srphasesco-existintwomorphologies,i.e.,blocky-likephaseandsurround-likephase,besides,whichbothhavethesamechemicalcompositionofAl_(34)Ti_3Sr.ThecrystalstructureofAl_(34)Ti_3Srisface-centeredcubic,andthelatticeparameterisdeterminedtobeabout1.52nm.
简介:目的探讨橙皮素(HES)对H2O2诱导的H9c2心肌细胞凋亡的影响.方法采用H2O2建立H9c2心肌细胞氧化应激损伤模型.实验分为4组:正常对照组(Control组)、H2O2损伤组(H2O2组)、单纯橙皮素处理组(HES组)、橙皮素预处理+H2O2组(HES+H2O2组).H2O2(400μM)处理2h建立心肌细胞氧化应激损伤模型,HES+H2O2组于建模前1h加入40μM橙皮素.采用CCK-8法确定H9c2细胞活性,DCFH-DA探针检测细胞活性氧簇(ROS)水平,流式细胞术检测心肌细胞凋亡,分光光度计检测Caspase-3活性.结果橙皮素预处理可明显改善H2O2诱导的H9c2心肌细胞活性降低,且浓度为40μM时保护作用最明显;给予40μM橙皮素预处理后ROS的产生明显减少,Caspase-3活性显著下降,心肌细胞凋亡率为(28.32±2.12)%,明显低于H2O2组(50.33±2.56)%(P〈0.05).结论橙皮素对氧化应激诱导的心肌细胞凋亡具有抑制效应.
简介:在密度以内的第一原则的计算功能的理论被执行了在Ti32阶段>艾尔基于合金,Zr,Hf,和Sn(6.25at%)元素做了。格子常数,全部的精力和有弹性的常数为supercells被计算。形成热含量,体积模量,砍模量,幼仔模量,和内在的坚硬被调查。做的2阶段的韧性被Cauchy压力,G/B和泊松比率分析。结果证明由由Sn的艾尔(2n)的Zr,Hf,和替换的Ti(6h)的替换能使做的2阶段更稳定。2阶段的刚性和坚硬能被与Zr和Hf做提高,当Sn带相反的效果时。Sn是更强大的比Hf改进做的2阶段的韧性,但是Zr能增加易碎物。状态(DOS和PDOS)的密度和差别费用密度被获得揭示alloying元素的效果的内在的机制。