简介：ThefirststarsintheearlyUniversewereformedabout400millionyearsafterthebigbang.VerificationoftheexistenceofthesestarsisimportantforourunderstandingoftheevolutionoftheUniverse[1].IthasbeenpredictedthatforPopulation-IIIstellarproductionyields,theabundancesofodd-Zelementsareremarkablydeficientcomparedtotheiradjacenteven-Zelements[2].Astronomersaresearchingforlong-lived,lowmassstarswiththeuniquenucleosyntheticpatternmatchingthepredictedyields[3].

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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.

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简介：Onenovelorganic-inorganichybridsupramolecularassemblies|（NDPA）（18-crown-6）]2+（DMA）+·3ClO4-（1）,hasbeensuccessfullyconstructedthroughtheprominentstrategiesofcrystalengineering（NDPA=N,N-dimethyI-1,4-phenylenediamine,DMA=dimethylamine）,andcharacterizedbyIR,powderXRDandsinglecrystalX-raydiffraction.Inthestructure,thesupramolecularorganiccationsandinorganicClO4-anionsarearrangedalternatelyandlinkedbyN-O…Hhydrogenbonds.ItisworthytonotethattheClO4-arelinkedtoformone-dimensionalinorganicchainthroughstrongNH…Ohydrogenbondsalongb-axis.Thereisnodistinctdielectricanomalyinthetemperaturedependentandfrequency-dependentdielectricconstantcurves,suggestingthatnophasetransitionexistswithinthemeasuredtemperaturerange（120-420K）.Therelativedisplacementofcationsandanions,theturnedpolarizationofmolecularelectricmomentandmacrocyclicmoleculerotatorarethemainfactorstodeterminethetrendofdielectricconstant.

简介：Radiotherapyisacommontreatmentmodalityforheadandneckcancers,nasopharyngealcancers,primarybraintumorsandbrainmetastases.Alargenumberofpatientsintheworldwithprimaryormetastaticbraintumorswillrequirelargevolumeorwholebrainirradiationeveryyear.However,therapeuticirradiationnotonlykillstumorcells,butalsoinjuresnormalbraintissue,whichiscommonlyassociatedwithsignificantfunctionalmorbidityanddecreasedqualityoflifeinpatientstreatedwithbrainradiotherapy[1].

简介：在有ArSSAr的THF的SmI2的反应生产了二binuclear钐thiolate建筑群[(THF)3I2-Sm(-SAr)]2[Ar=Ph(1)，4-Me2NC6H4(2)]在高收益。2的结构被单个水晶X光检查晶体学描绘。2的水晶与空格组和a=0.95705(13)一起属于三斜晶系的系统nm，b=1.22287(14)nm，c=1.26450(14)nm，=64.194(11)??匭吗？？v？？

简介：Theabinitiogeneralizedgradientapproximation（GGA）＋Ustudyofmultiferroic（La0.5Bi0.5）2FeCrO6inpnmastructureandferri-magneticorder,includingHubbardcorrections（U-4.1eV）fortransitionmetal/rareearthd-electronswith20atomscell,showsoptimumlocalmagneticmomentsof（Cr^3＋,Fe^3＋）equalto（-2.56,4.14）#Bandanidealspin-downbandgapof1.54eV.Tuned-bandgapLa-substituteddoubleoxideperovskitesBFCOshouldexhibitenhancedvisible-lightabsorptionandcarriermobility,thuscouldbeconvenientlightabsorbersandthenefficientalternativestowide-gapchalcopyriteabsorber-basedsolarcellsfailingtoachievehighestpowerconversionefficiencies,andevencompetewiththeirmetal-organichalideperovskitescounterparts.

简介：利用PCR以实验室构建的原核重组表达质粒pProEX-OCIF为模板扩增得到N末端融合有6×His标签和rTEV蛋白酶识别序列的人破骨细胞形成抑制因子(OsteoclastogenesisInhibitoryFactor,简称OCIF)结构域D1～D6(简称OCIFm)编码基因片段;将其与pMD18-T连接,转化大肠杆菌TOP10,筛选得到阳性重组质粒pMD18-OCIFm,双酶切重组克隆质粒pMD18-OCIFm得到OCIFm基因片段;将其定向插入甲醇营养型酵母分泌表达载体pPIC9中,构建获得重组表达质粒pPIC9-OCIFm.测序验证后,以限制性内切酶SalⅠ线化,电穿孔转化酵母宿主菌GS115.筛选得到阳性表达菌株后,甲醇诱导表达4d,SDS-PAGE和Westernblot对表达情况进行分析和确认.所获得的OCIFm基因片段在甲醇营养型酵母中表达量占菌体总蛋白的30%以上.利用Ni-NTA树脂对表达产物进行一步亲和层析纯化.活性测定表明纯化的表达产物可诱导体外培养的成熟破骨细胞样细胞的凋亡.表达产物的生物学活性较利用原核表达系统明显提高.

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简介：运用水热法合成了1个新的配合物[Ni（Phtpy）2]（CH3COO）2（化合物1）,（Phtpy=4′-苯基-2,2′∶6′,2″-三联吡啶）,并通过X-射线单晶衍射方法确定了该化合物的晶体结构.结构分析表明化合物1属于三斜晶系,P-1空间群,晶胞参数a=0.90560（8）nm,b=1.10307（9）nm,c=2.02014（15）nm,α=94.3830（10）°,β=100.9830（10）°,γ=106.3120（10）°,V=1.8831（3）nm3,Z=2,R1=0.0872,wR2=0.1831.配合物中存在3种氢键和多种π-π相互作用,使其成为一个3D配合物.

简介：H+-restackednanosheetsandnanoscrollspeeledfromK4Nb6O17displaydifferentstructuresandsurfacecharacters.Thetworestackedsampleswithincreasedsurfaceareashaveanamazingvisible-lightresponseforthephotodegradationofdyes,whichissuperiortocommercialTiO2(P25)andNb2O5.Bycomparison,H+/nanosheetshavearelativelyfasterphotodegradationrateoriginatedfromlargeandsmoothbasalplane.Theworkrevealsthatdyeadsorbedontheunfoldednanosheetscaneffectivelyharvestsunlight.Duetofacilepreparation,low-costandhighphotocatalyticefficiency,H+/nanosheetsandH+/nanoscrollsmightbeusedforthevisiblelight-drivendegradationoforganicdyesasasubstituteforTiO2inindustry.

简介：Afacilesolidphasesynthesisof2-substituted1,3-oxazin-6-onesusingpolymer-supportedMeldrum'sacidhasbeenreported.Reactionoftheresin-boundcyclicmalonicacidesterwithtriethylorthoformateandsubsequentdoublesubstitutionwithamide,affordedthecorrespondingpolymer-supportedacylaminomethylenecyclicmalonicacidester,whichuponthermaltreatmentledto1,3-oxazin-6-onesingoodyieldsandwithhighpurity.

简介：利用水热合成方法合成了1个新型类杯芳烃修饰的Keggin型超分子化合物Ag6L6（PMo12O40）2（1）（L=5-甲基四氮唑）,其中6个5-甲基四氮唑配体和6个银配位形成了类杯[6]芳烃的多核银配合物.通过红外光谱、元素分析和X射线单晶衍射方法确定了该化合物的晶体结构.单晶结构分析表明化合物1属于六方晶系,R-3空间群,晶胞参数a=1.77908（8）nm,b=1.77908（8）nm,c=2.40885（19）nm,α=90°,β=90°,γ=120°,V=6.6028（7）nm3,Z=3.

简介：采用微波消解技术,建立了电感耦合等离子体质谱法同时测定大米中Pb,Cd,As,Tl,Cr和V6种重金属元素的方法.完善了样品前处理条件,优化了仪器工作参数,并选取115In,209Bi和45Sc作为内标元素,有效地克服了基体效应和仪器波动的影响.在最优的实验条件下,方法的检出限为0.067～27.5ng/L,测定元素的标准曲线相关系数均大于0.999.方法经国家一级植物标准物质验证,结果与推荐值相符.

简介：采用Tessier连续提取法对延安市污水处理厂污泥中的Zn、Cu、Cr、Cd、Pb和Mn六种重金属元素进行形态提取，并用电感耦合等离子体发射光谱（ICP—AES）法对其中各元素的总量及其形态进行测定。结果表明：Pb、Cd多以可交换态、碳酸盐结合态存在，分别占总量的76．84％和78．59％，对生物具有潜在有效性。Zn、Cu、Cr多以稳定的硫化物及有机结合态和残渣态存在，不易迁移到环境中去。