简介:Thetitlecomplexi-C4H9Co(salen)(Py)(Py=pyridine.salen=dianionofdisalicylideneethylenediamine)hasbeenfirstsynthesized.ItscrystalstructurehasbeendeterminedbyX-raydiffractionmethod.ThecrystsisaremonoclinicwithspacegroupP21/C.Theunitcellparametesarepresented.ThestructurehasbeenrefinedtoafinalRof0.038.
简介:Anovelseriesofpyrido[1,2-e]purin-4(3H)-onederivativescontainingpolarsubstituentson5'-positionweredesignedandpreparedaspotentialPDE5inhibitors.Thispaperreportsthesyntheticroutes,1H-NMRdata,andthePDE5inhibitoryactivitiesofthetargetcompounds.Thepolarpiperazinylgroupcontained(on5'-position)compound,3B2,showedthehighestactivityamongthetestedderivativesbutlesspotencythansildenafil1.
简介:摘要改革开放以后,我国的社会经济进入了高速发展的新时期,国家的综合国力和国际影响力得到了稳步提升,中国的社会经济成就让世界为之瞩目。随着国家整体发展形势的向好,人们的生活水平也得到了稳步提升,城镇燃气供应作为重要的民生工程在新时代获得了极为长足的发展。当前我国城镇燃气的普及率较以往得到了极大的提升,燃气供应的效率、安全,燃气管理的科学、有效,成为了人们关注的焦点。物联网技术在城镇燃气管理中的应用可以极大的提高燃气管理的质量水平,让城镇燃气管理工作形成体系、产生规模。本文从物联网技术的概念入手,以湖南某城市燃气示范系统为例,对城镇燃气管理中物联网技术的应用进行了相应的分析和论述,希望能够给相关的工作人员以参考启示,推动我国城镇燃气管理工作的进一步发展。
简介:DrivenbycuriosityaboutpossibleflightoptionsfortheChang’e-2spacecraftafteritremainsattheSun-EarthL2point,effectiveapproachesweredevelopedfordesigningpreliminaryfuel-optimalnear-Earthasteroidflybytrajectories.Theapproachesincludetheuseofmodifiedunstablemanifolds,gridsearchofthemanifolds’parameters,andatwo-impulsemaneuverfororbitalphasematchingandz-axisbiaschange,andaredemonstratedtobeeffectiveinasteroidtargetscreeningandtrajectoryoptimization.Asteroidflybysareexpectedtobewithinadistanceof2×107kmfromtheEarthowingtotheconstrainedEarth-spacecraftcommunicationrange.Inthiscase,thespacecraft’sorbitalmotionissignificantlyaffectedbythegravitiesofboththeSunandtheEarth,andtherefore,theconceptofthe"heliocentricoscillating-Keplerorbit"isproposed,becausetheclassicalorbitalelementsoftheflybytrajectoriesreferencedintheheliocentricinertialframeoscillatesignificantlywithrespecttotime.Theanalysisandresultspresentedinthisstudyshowthat,amongtheasteroidswhoseorbitsarethemostaccuratelypredicted,"Toutatis","2005NZ6",or"2010CL19"mightbeencounteredbyChang’e-2inlate2012or2013withtotalimpulseslessthan100m/s.
简介:Startedfrom5-hydroxy-2-pentanone,(R)(E)-3,7-dimethyl-2-octene-1,8-dioicacid,callosobruchusicacid,wassynthesizedviafivestepswithD-(-)-camphorsultamasthechiralauxiliary.Itwasofgoodopticalpurityandyield.
简介:ACupro-8-thioquinolinecoordinationpolymer,[Cu^I(C9H6NS)]n,wassynthesizedbymethano-thermalreactionofCuCland8,8′-dithiodiquinoline(dtdq)inamolarratioof2:1at160℃for7d.X-Raysinglecrystalstructuredeterminationrevealedtheformationofaone-dimensionalstructurebelongingtomonocliniccrystalsystem,spacegroupP21/cwithcellparametersa=0.8043(1)nm,b=1.8949(3)nm,c=1.1048(1)nm,β=110.109(4)°,V=1.5810(4)nm^3andZ=4,Thecrystalwasfoundtobestableuptoapproximately300℃bythermalanalysisandhaveanenergygap(Eg)of2.0eVexhibitedbyUV-Vis-NIRreflectancespectrum.
简介:采用硝酸-盐酸-氢氟酸-高氯酸溶样,优化仪器测定条件及消除干扰元素的条件实验等,建立了电感耦合等离子体发射光谱(ICP—OES)法测定铅精矿中砷、锑、铋、铜、锌、镁、铝、铁、镉的方法。其测定范围ω(As):0.02%~1.50%;ω(Sb):0.010A~10.00%;ω(Bi):0.03%~5.00%;ω(Cu):0.50%~10.00%;ω(Zn):2.00%~10.00%;ω(Mg):0.30%~2.00%;ω(A1):0.50%~3.00%;ω(Fe):5.00%~12.00%;ω(Cd):0.030%~0.20%。经加标回收实验,各元素的加标回收率为90%~104%(n=3)。方法准确、快速、可靠,适用于铅精矿中砷、锑、铋、铜、锌、镁、铝、铁、镉量的同时测定。
简介:Theeffectandmechanismofcarmustine(BCNU)combinedwithall-transretinoicacid(ATRA)ontheapoptosisofhumanglioblastomaU251cellswereinvestigatedbymeansof3-(4,5-dimethylthiazol-2-yl)-2,5-diphe-nyltetrazoliumbromide(MTT)assay,flowcytometry,reversetranscription-polymerasechainreaction(RT-PCR)andWesternblotanalysis.TheresultsshowthatBCNUorATRAshowstime-anddose-dependentinhibitioneffectsonhumanglioblastomaU251cellsandthecombinationofBCNUwithATRAshowsansynergisticinhibitioneffectonhumanglioblastomaU251cells,andthecombinedBCNUandATRAcansignificantlyinhibittheproliferationofhumanglioblastomaU251cells,andinducetheapoptosisofthem,makingthecellsarrestinthestageofG1phase,thestageofSandG2phasesdecline,therateoftheapoptosisofhumanglioblastomaU251cellsincrease,thecorrespondingmRNAexpressionofcyclinEandcyclin-dependentkinase2(CDK2)downregulatedandthecorrespon-dingmRNAexpressionofp27kip1unregulated.Inaddition,thecombinedBCNUandATRAreducedtheproteinexpressionofnuclearfactorkappaB(NF-κB).Takentogether,theseresultssuggestthatthetreatmentofhumanglioblastomaU251cellswithacombinationapplicationofATRAandBCNUcanexertsynergisticeffect,thecourseofthiskindofcombinationchemotherapymaylikelybeassociatedwithmultiplemolecularmechanismsforapoptosis,furthermore,thecyclinEandp27kip1shouldbeconsideredasnoveltargetsforcontrollingthegrowthofglioblastomacells.
简介:ThecomplexK3H4GeW9V3O40·8H2OcrystallizedinamonocliiniesystemwithspacegroupP2,Mr=2784.67,a=11.099(3),b=16.452(4),c=13.534(4),β=108.14°,Z=2,V=2348.493,F(000):2456,μ=239.7cm-1,De=3.932g/cm3.ThefinalR=0.083for4528non-zeroreflexions.ThestructureofanionsGeW9V3O40andGeW9O34belongstoA--type.
简介:建立了提取和清洗整合成一步的超声辅助-固相分散溶液提取离子色谱法测定染发剂中的9种染料中间体的方法。样品基质经分散后,测定组分进入溶液,油脂溶解在正已烷中,干扰化合物被分散剂吸附。在振荡、超声和加热的协同作用下,9min内快速完成提取,具有高的样品处理效率。用离子色谱法测定商业染发剂中的中间体以确定方法的提取效率。方法的线性范围为0.2-100mg/L,检出限0.019-0.048mg/L,回收率85.0%-107.0%,相对标准偏差0.30%-3.7%。实验结果表明,方法简单、可靠,适用于大批量样品的常规分析。
简介:Anovelaciddyeacidwassynthesizedbythecondensationreactionbetweenbromamineacidand2-amino-6-nitrobenzothiazoleanditsanti-UVprotectionpropertieswereevaluated.Theresultsshowedthatsilkdyedwiththisdyehadverygoodultravioletradiationprotectioncapabilityandexcellentdyeingperformance.TheUV-absorptionmechanismofthisdyewasalsodiscussed.
简介:Anovelsupportedliquidphasefilmcatalyst:SupportedPdCl2-(n-C4H9)4N+Cl-moltensaltswasfoundtobeaneffectivecatalystwithgoodstabilityforselectivehydrodechlorinationofCCl2F2(CFC-12)toitsalternativesCH2F2andCHClF2.AdditionofCoCl2,GaCl3andCuCl2toPdCl2-(n-C4H9)4N+Cl-modifiesthecatalyticperformanceofsupportedmoltensalts.