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218 个结果
  • 简介:Basedonsystematicalresearchontheconceptionevolutionofecologicalenterprise,theoreticalandpracticaldevelopmentofconstructingecologicalenterprise,thepapermakesconclusionthatecologicalenterprisesaredevelopingintoanewstageinwhichgovernmentsarelaunchingsomepilotprojectsaboutconstructingecologicalenterprises.Andafterthat,governmentsshouldmakepoliciestospreadconstructionofecologicalenterprises,toconstructecologicalenterprisesinlegalsystemandconformingtothestandardassoonaspossibly.5othat,thebasicunitsofecologicaleconomythatfittotheconditionsofChinawillbesetup.

  • 标签: 中国 少废无废工艺 清洁生产 循环经济 生态效益企业理论 企业管理
  • 简介:尽管边界排水量和拖拉是处于在一个非退化的边界点的一个弹性问题的边界条件的独立的地变量,在那里存在在在一条单个边界的边界排水量衍生物和拖拉之间的奇特紧张的明确的关系指。在为2D的一个单个光滑的点的关系的分析表格各向同性的有弹性的问题在这个工作被建立了。由使用关系,单个边界点的位置和未知边界的相应奇特紧张回答变量能被决定priori。因此,未知边界的更适当的形状函数在单个元素回答变量能被构造。一个数字例子证明用发达理论的BEM分析的精确性极大地被增加。

  • 标签: 边界移位牵引 不连续性 奇异边界点 等方弹性问题 弱奇点
  • 简介:Thegeometricalstructuresof2-(2-hydroxyphenyl)pyridine(PP)anditsprotonationstateswereoptimizedbymeansoftheB3LYP/6-31G(d)method.Foralltheselectedsystems,theexistenceofH-bondisinfavorofthestabilityofthesystems.Onthebasisoftheoptimizedgeometricalstructures,theirelectronicspectrumpropertieswerestudiedbytime-dependentdensityfunctionaltheory(TD-DFT)methosdviaahybridfunctionofB3LYPand6-31G(d)basisset.TheTD-DFTcalculationresultpredictstheabsorptionspectrumofPPat324nm(3.82eV),whichisinverygoodagreementwiththeexperimentalvalueof322nm(3.85eV)determinedinsolventchloroform.TheabsorptionspectraofthetwoprotonationstatesbothexertaredshiftinvariouspHmedia.

  • 标签: 理论研究 电子光谱 密度 2-(2-羟苯基)嘧啶 光谱性质
  • 简介:Thispaperinvestigatesthetemperaturefielddistributionandthermalfocallengthwithinalaserdiodearray(LDA)end-pumpedYVO4/Nd:YVO4rectangularcompositecrystal.AgeneralexpressionofthetemperaturefielddistributionwithintheNd:YVO4rectangularcrystalwasobtainedbyanalysingthecharacteristicsoftheNd:YVO4crystalandsolvingthePoissonequationwithboundaryconditions.ThetemperaturefielddistributionsintheNd:YVO4rectangularcrystalfortheYVO4/Nd:YVO4compositecrystalandtheNd:YVO4singlecrystalareresearchedrespec-tively.CalculatingthethermalfocallengthwithintheNd:YVO4rectangularcrystalwasdonebyananalysisoftheadditionalopticalpathdifferences(OPD)causedbyheat,whichwasveryidenticalwithexperimentalresultsinthispaper.ResearchresultsshowthatthemaximumrelativetemperatureontherearfaceoftheNd:YVO4crystalinthecompositecrystalis150Kandthethermalfocallengthis35.7mmwhentheoutputpoweroftheLDAis22W.Inthesamecircumstances,theexperimentalvalueofthethermalfocallengthis37.4mm.Sotherelativeerrorbetweenthetheoreticalanalysisandtheexperimentalresultisonly4.5%.Withthesameconditions,thethermalfocallengthoftheNd:YVO4singlecrystalis18.5mm.SotherelativerateofthethermalfocallengthbetweentheYVO4/Nd:YVO4crystalandtheNd:YVO4crystalis93%.So,thethermalstabilityoftheoutputpowerandthebeamqualityoftheYVO4/Nd:YVO4laserismoreadvantageousthanthelaserwithNd:YVO4singlecrystal.

  • 标签: YVO4晶体 激光二极管阵列 复合晶体 热焦距 实验值 Nd
  • 简介:Inthiswork,somechemometricsmethodsareappliedforthemodelingandpredictionoftheHildebrandsolubilityparameterofsomepolymers.Ageneticalgorithm(GA)methodisdesignedfortheselectionofvariablestoconstructtwomodelsusingthemultiplelinearregression(MLR)andleastsquare-supportvectormachine(LS-SVM)methodsinordertopredicttheHildebrandsolubilityparameter.TheMLRmethodisusedtobuildalinearrelationshipbetweenthemoleculardescriptorsandtheHildebrandsolubilityparameterforthesecompounds.ThentheLS-SVMmethodisutilizedtoconstructthenon-linearquantitativestructure-activityrelationship(QSAR)models.TheresultsobtainedusingtheLS-SVMmethodarethencomparedwiththoseobtainedfortheMLRmethod;itwasrevealedthattheLS-SVMmodelwasmuchbetterthantheMLRone.Theroot-mean-squareerrorsofthetrainingsetandthetestsetfortheLS-SVMmodelwere0.2912and0.2427,andthecorrelationcoefficientswere0.9662and0.9518,respectively.ThispaperprovidesanewandeffectivemethodforpredictingtheHildebrandsolubilityparameterforsomepolymers,andalsorevealsthattheLS-SVMmethodcanbeusedasapowerfulchemometricstoolforthequantitativestructure-propertyrelationship(QSPR)studies.

  • 标签: 溶解度参数 定量构效关系 分子描述符 聚合物 SVM技术 最小二乘支持向量机
  • 简介:Anopticalbandpassfilter(OBF)isanimportantelementwhosepropertiesconsiderablyinfluencetheoutputperformanceofasinglesidebandmulticarriersourcebasedonare-circulatingfrequencyshifter.TheinfluenceoftheOBFintheloopontheoutputspectrumistheoreticallyanalyzed.Numericalsimulationsandexperimentsarealsocarriedout.Resultsshowthatthesteepnessanddeepnessofanonflat-topfilterinfluencethestabilityofthespectrumofanoutputmulticarrier.Toobtainmulticarrieroutputwithtonetonoiseratio(TNR)>26dBanderrorvectormagnitude(EVM)<0.25,thesteepnessratioofthefiltershouldbegreaterthan0.75anddeepnessshouldbelargerthan0.99.

  • 标签: 输出性能 带通滤波器 移频器 循环 基础 波源
  • 简介:Sincethe18thNationalCongressoftheCommunistPartyofChina(CPC),thesystemforthelegalprotectionofhumanrightsundersocialismwithChinesecharacteristicshasexperiencedinnovativedevelopment.Inparticular,theDecisiononCertainKeyIssuesonComprehensivelyDeepeningReform,whichwasadoptedbytheThirdPlenarySessionofthe18thCPCCentralCommittee,

  • 标签: 法律保护 中国共产党 人权 创新 中国特色社会主义 社会主义制度
  • 简介:AhomogeneoustheoreticalmodelisdevelopedtopredicttheperformanceofR22andR290inadiabaticcapillarytubes.Themodelisbasedonconservationequationsofmass,momentumandenergy.Metastablebothliquidandtwo-phaseflowregionsareconsideredinthemodel.Inmetastabletwo-phaseregion,superheatedliquidisintroducedintothemetastablemixtureviscosityandtwomethodsarepresentedtoevaluateit.Themodelisvalidatedbycomparingthepredictedpressureandtemperatureprofileandmassflowratewithseveralinvestigators′experimentaldataofR22andoneofitsalternativesR290reportedinliterature.Allofthepredictedmassflowratesarewithin±8%ofmeasuredvalues.Comparisonsarealsomadebetweenthepresentmodelandotherinvestigators′modelsorsizingcorrelation.Themodelcanbeusedfordesignorsimulationcalculationofadiabaticcapillarytubes.

  • 标签: 数字模型 隔热毛细管 同类模型 亚稳流程 二相流程
  • 简介:氢蚁的酸的结合的相互作用--,甲醛--,formylfluoride-nitrosyl氢化物建筑群被密度调查功能的理论(DFT)和与6-311++G(2d,2p)一起的abinito方法基础集合。几何学,震动的频率和建筑群的相互作用精力被标准、改正CP的方法分别地计算。而且,G3B3方法被采用估计相互作用精力。有CH??O,NH??O,NH??F转移蓝色的H契约并且转移红哦??在建筑群的OH契约。电子密度再分配和杂交贡献NH和CH蓝色移动。所有几何重组贡献NH蓝移动,部分几何重组贡献CH蓝移动。复杂C除了的几何重组(H(5)-O(4)-C(1)贡献OH红移动。为NH蓝移动,r的效果(没有)NH蓝移动上的变化比的大(H-N-O变化。杂交在NH蓝移动的度起一个主导的作用,而电子密度再分配比另外的效果贡献更多到CH蓝移动的度。

  • 标签: 红移氢键 蓝移氢键 相互作用能 蚁酸 甲醛 甲酸基氟化物