简介：图的染色是图论中非常重要的研究课题,图的染色的基本问题即是确定各种染色法的色数.图G的邻点可区别I-全染色是一个新的染色概念,对二幂图P2n的邻点可区别I-全染色问题进行了研究,从其结构特点出发,运用构造法和色调整技术,给出了P2n的邻点可区别I-全染色法,得到了P2n的邻点可区别I-全染色数.
简介：Accordingtothegoodchargetransportingpropertyofperovskite,wedesignandsimulateap–i–n-typeall-perovskitesolarcellbyusingone-dimensionaldevicesimulator.Theperovskitechargetransportinglayersandtheperovskiteabsorberconstitutetheall-perovskitecell.Bymodulatingthecellparameters,suchaslayerthicknessvalues,dopingconcentrationsandenergybandsofn-,i-,andp-typeperovskitelayers,theall-perovskitesolarcellobtainsahighpowerconversionefficiencyof25.84%.Thebandmatchedcellshowsappreciablyimprovedperformancewithwidenabsorptionspectrumandloweredrecombinationrate,soweobtainahighJ_(sc)of32.47mA/cm~2.Thesmallseriesresistanceoftheall-perovskitesolarcellalsobenefitsthehighJ_(sc).Thesimulationprovidesanovelthoughtofdesigningperovskitesolarcellswithsimpleproducingprocess,lowproductioncostandhighefficientstructuretosolvetheenergyproblem.
简介：在这篇论文，我们与州依赖者的服务学习一个排队系统andstate依赖的假期，或简单地G/M(n)/1/K。因为服务率是州依赖者的，这个系统作为特殊情况与车站假期的各种各样的类型包括G/M/c和G/M/c/K队列。我们用增补可变技术提供一个递归的算法数字地计算系统的静止队列长度分发。唯一的输入要求是theLaplace-Stieltjes变换内部到达分发以及州依赖者的服务率和州依赖者的假期率。在一份随后的同伴报纸，我们与州依赖者的假期学习它的双systemM(n)/G/1/K队列。
简介：Twooxo-vanadium(IV)complexes,[VO(C2O4)(2,2′-bipy)(H2O)]·C2H5OH(1)andVO(C2O4)(phen)(H2O)(2),where2,2′-bipy=2,2′-bipyridyl,phen=1,10-phenanthroline,weresynthesizedaspotentialfunctionalmodelsofvanadiumhaloperoxidases(VHPOs)inmixedsolventofethanolandwateratroomtemperature.Thecomplexeswerecharacterizedbyelementalanalysis,infrared(IR),UV-VisandX-raycrystallography.Structuralanalysesshowedthatvanadiumatomwascoordinatedbyaterminaloxygen,oneoxygenatomfromcoordinatedwater,twooxygenatomsfromthecarboxylategroupofoxalicacid,andtwonitrogenatoms(N1andN2)from2,2′-bipy/phen.Centralvanadiumatomsincomplexes1and2werebothinadistorted-octahedralenvironment,andsomeintermolecularhydrogenbondinglinkageswerealsoobservedineachcomplex.BrominationreactionactivityofthetwocomplexeswasevaluatedwithphenolredasorganicsubstrateinthepresenceofH2O2,Br-andphosphatebuffer,indicatingthattheycanbeconsideredasapotentialfunctionalmodelofVHPO.Inaddition,thermalanalysiswasalsoperformedanddiscussedindetail.
简介：Themononuclearcomplex,[NtCl2(trzCHzCHzCOPh)4]·6H2O(trz=1,2,4-triazole),wassynthesizedanditsstructurewasdeterminedbysinglecrystalX-raydetermination.Itcrystallizesinthemonoclinicsystem,spacegroupP21/c,withlatticepa-rameters:a=0.80391(2)nm,b=1.06215(2)nm,c=2.90133(2)nm,β=94.792(1)°andZ=2.EachnickelatomiscoordinatedbyfourNatomsoftriazolefromfourβ-(1,2,4-IriHole-1-yl)propiophenoneligandsandtwochlorideanionsinarrangementwithoctahedralcoordinationgeometry.Inadditiontothecoordinatingnickelcomplex,therearesixunco-ordinatedwatermolecules.TheNi—Ndistanceis0.24865(8)nmandtheNi—Ndistaneesareintherangeof0.2072(2)to0.2099(2)nm,respectively.Inthesolidstate,theUtiecom-poundformsthreedimensionalnetworkstructurethroughhy-drogenbonds.Theintermolecularhydrogenbondsconnectthe[NiCl2(C2H2N3CH2CH2COPh)4]andH2Omoieties.Thedeepgreencrystalswerealsoexaminedbyelementalanalysis,FT-IRandUVspectra,whichareinagreementwiththestructuralda-ta.
简介：ThefirststarsintheearlyUniversewereformedabout400millionyearsafterthebigbang.VerificationoftheexistenceofthesestarsisimportantforourunderstandingoftheevolutionoftheUniverse[1].IthasbeenpredictedthatforPopulation-IIIstellarproductionyields,theabundancesofodd-Zelementsareremarkablydeficientcomparedtotheiradjacenteven-Zelements[2].Astronomersaresearchingforlong-lived,lowmassstarswiththeuniquenucleosyntheticpatternmatchingthepredictedyields[3].
简介：有alloying原子X=C，B，N，O和空缺的镁和它的合金的概括叠的差错(GSF)精力和表面精力用第一原则的方法被调查了。叠的差错精力上的alloying原子和空缺的占优势的减少效果在slip飞机附近在第一层从他们的位置被结果，这被发现。叠的差错精力是将近与纯镁一样当alloying原子和空缺被放在时第二，第三，第4，第5和第6层。O强烈减少Mg的GSF精力，这被显示出。alloying原子C，B和N增加表面精力，但是O和空缺减少Mg的表面精力。Mg和Mg合金的韧性被使用在表面精力和不稳定的叠差错精力之间的比率基于瑞斯标准讨论了。
简介：为揭示大麦中黄酮合成的分子调控机制,利用反转录PCR结合同源克隆和RACE技术首次从青稞（裸大麦）叶片中克隆获得肉桂酸-4-羟化酶基因（HvC4H）的全长cDNA序列（Genbank登录号：KF927086）,总长度1951bp,ORF为1518bp,编码505个氨基酸,等电点PI=9.01,平均亲水指数（GRAVY）为-0.170,属于亲水性碱性蛋白,高级结构分析表明其具有细胞色素P450家族保守域及C4H特异的功能性活性位点。利用实时荧光定量PCR分析胚乳发育5个时期不同组织（茎、叶及子粒）的表达情况,结果显示HvC4H基因在青稞胚乳发育期的表达情况存在着明显的组织差异性,在茎中的表达量最高。本研究为通过调控C4H基因的表达从而提高大麦黄酮的含量奠定了分子生物学基础,对于改良大麦的品质、抗性、生长发育等性状具有重要意义。
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![Vanadium Haloperoxidases Model Compounds： Synthesis, Structural Characterization and Mimic Catalytic Bromination Activity of [VO（<b style='color:red'>C</b>_2O_4）（2,2′-bipy）（<b style='color:red'>H</b>_2O）]·<b style='color:red'>C</b>_2<b style='color:red'>H</b>_5OH and VO（<b style='color:red'>C</b>_2O_4）（phen）（<b style='color:red'>H</b>_2O）](/image/thesis6 "Vanadium Haloperoxidases Model Compounds： Synthesis, Structural Characterization and Mimic Catalytic Bromination Activity of [VO（<b style='color:red'>C</b>_2O_4）（2,2′-bipy）（<b style='color:red'>H</b>_2O）]·<b style='color:red'>C</b>_2<b style='color:red'>H</b>_5OH and VO（<b style='color:red'>C</b>_2O_4）（phen）（<b style='color:red'>H</b>_2O）")
![Structure of Tetra[β-（1,2,4-triazole-l-yl） propiophenone ] Dichloro NiCkel（Ⅱ） Solvate Hexahydrate Complex：[NiCl2 （ <b style='color:red'>C</b>2<b style='color:red'>H</b>2<b style='color:red'>N</b>3CH2CH2-COPh） 4 ]·6<b style='color:red'>H</b>2O](/image/thesis8 "Structure of Tetra[β-（1,2,4-triazole-l-yl） propiophenone ] Dichloro NiCkel（Ⅱ） Solvate Hexahydrate Complex：[NiCl2 （ <b style='color:red'>C</b>2<b style='color:red'>H</b>2<b style='color:red'>N</b>3CH2CH2-COPh） 4 ]·6<b style='color:red'>H</b>2O")
