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  • 简介:SincethedesignstudiesofsolidtritiumbreederblanketmodelshavebeenperformedbyJapanandEUC,andtheirTBMdesignoptionsforITERhavebeenproposed.InordertodesignourTBMblanketoptionswithChineseresearchbasesandexperiences,wechoseliquidlithiumorlithium-leadasthetritiumbreedingmaterialsforourTBMblanketoptions.Howeverthethicknessoffirstwallisusuallyonlyafewcentimeters,

  • 标签: ITER 第一壁 偏滤器靶板 热负荷 氚增殖包层模块
  • 简介:Thispaperstudiesthedevelopmentonthefirstorderseacluttercrosssectionforbistatichighfrequencysurfacewaveradar(HFSWR).Basedonthereceivedfirstorderelectricfieldexpression,aclosed-formofcrosssectionsisderivedtoaccountforthecaseofreceivingantennaarraybeingmountedontheshipborneplatform.Theuniformlinearmotionandswaymotioncomponentsareassumedtoberesponsiblefortheobserveddifferencesincomparisonwiththebistaticfixedantennacase.Correspondingly,simulationsareconductedtostudytheseaclutterspectralcharacteristicsforthesetwocasesversusdifferentsystemparametersandseastateconditions.ItisshownnumericallythattheforwardmotioncomponentwillspreadtheBragglinesseverelyandtheinfluencetriggeredbytheswaymotioncanbeexplainedastheBesselfunctionmodulationoftheordinaryseaclutterspectra.TheobtainedresultshaveimportantimplicationsintheapplicationofshipborneHFSWRtechnologytooceanremotesensingandtargetdetection.

  • 标签: RADAR cross section (RCS) remote sensing
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  • 简介:Inthispapertheexistenceresultsofpositiveω-periodicsolutionsareobtainedforsecondorderordinarydifferentialequation-u″(t)=f(t,u(t))(t∈R),andalsoforfirstorderordinarydifferentialequationu′(t)=f(t,u(t))(t∈R),wheref:R×R+→Risacontinuousfunctionwhichisω-periodicint.Thediscussionisbasedonthefixedpointindextheoryincones.

  • 标签: 正周期解 微分方程 圆锥体 不动点指数
  • 简介:Thefirstbirthmarksatransitionofawomanintomotherhood.Itcontributessubstantiallytooverallfertilityofeachindividualwoman.Theageatwhichchildbearingbeginsinfluencesthenumberofchildrenawomanbearsthroughoutherwholereproductivelifespan.Thus,themother’sageatfirstbirthinfluencesthetotalnumberofbirthsthatshemighthaveinherlife,whichimpactsthesize,composition,andfuturegrowthofthepopulation.Child-bearingatveryyoungagesiscommonamongthepoorinBangladesh.Theobjectiveofthepresentstudyistoexaminethefactorsassociatedwithageatfirstbirthamongslumdwellersoffiveselectedslums(locally,colony)inSylhetcitycorporationarea,Bangladesh.Thedataofthisstudywascollectedfrom520womenaged14-50years.Thestudyfoundthatalmost93%ofwomenweremarriedbytheagesof18yearsandabout56%ofthewomenhavehadtheirfirstchildbytheageof18years.TheOrdinaryLeastSquares(OLS)regressionmodelwasusedtoanalyzethefactorscorrelatedwithwomen’sageatfirstbirth.TheregressionmodelissignificantwithanF-valueof49.48andcanexplain40.4%ofthevariationinthedependentvariableasitisindicatedbytheR-square.

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  • 简介:ThisReviewfocusesonopticaltransmissionfibersandthehigh-capacitysystemsoperatingthereon.Itattemptstocombinekeylessonslearnedfromthe50-yearhistoryoflow-lossopticalfiberswithviewsonfuturefiberandsystemsrequirements,discussinglikelyevolutionpathsandpotentialpitfallsinresolvingtheopticalnetworkcapacitycrunch.

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  • 简介:ChinaTertiaryIndustryFirstNationalCensus:SelectedSummaryStatistics¥//Inlate1994,Chinacompleteditsfirstnationalcensusofitstert...

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  • 简介:WhatisPADIS-INT?PDIS-INTisthesoftwareuniversallyappliedinpopulationprojection,whichisdevelopedbyCPDRCwiththeguidanceandsupportofDirectorofPopulationDivision/DESA,UnitedNations,basedontheadvancedtechnologiesusedintheoriginalversionofPADIS.Applyingtheadvancedcom-putertechnologiesinpopulationprojection,thesoftwarehasfollowingthreefeatures:1.theJAVAvirtualmachineassurestheirrelevancebetween

  • 标签: 培训研讨会 诠释 国际 中国人口 技术服务 协调机构
  • 简介:二新自然杂环的混合物bretschneiderazinesA(2)和B(3)的灵巧的合成,从Bretschneiderasinensis的茎的一篇摘录孤立,被报导。我们作为关键步骤与硫和光气由指导lithiation和顺序的处理采用了benzamide的环合反应。所有新混合物充分借助于红外,1HNMR,13CNMR,和HRMS被描绘了。

  • 标签: 杂环化合物 全合成 简便合成 环化反应 红外特征 新化合物
  • 简介:平衡格子常数,体积模量的温度依赖,规范的体积V/V-0的压力依赖,有弹性的常数C-ij和LaNi5水晶的体积模量用在GGA-PBE的假潜在的方法概括了的第一原则的飞机波浪被获得坡度近似以及伪泛音Debye模型。我们分析在体积模量和温度之间的关系直到1000K并且在不同温度获得在体积模量B和压力之间的关系。体积模量B与增加压力单调地增加,这被发现。而且,Debye温度的压力依赖和格子常数的压力衍生物成功地也被获得。计算结果与试验性的数据和另外的理论结果一致。

  • 标签: 弹力 LANI5 晶格 混合物
  • 简介:Naturalgashydrates(NGH)isoneofkeyfuturecleanenergyresources.Itsindustrializeddevelopmentwillhelpremitthehugedemandofglobalnaturalgas,relievetheincreasingpressureoftheenvironment,andplayavitalroleinthegreensustainablegrowthofhumansocieties.Basedonnearlytwodecades'studyingonthereservoircharacteristicsintheSouthChinaSea(SCS)andtheknowledgeofreservoirsystem,theChinaGeologicalSurvey(CGS)conductedthefirstproductiontestonanoptimaltargetselectedinShenhuareaSCSin2017.Guidedbythe"three-phasecontrol"exploitationtheorywhichfocusedonformationstabilization,technologiessuchasformationfluidextraction,welldrillingandcompleting,reservoirstimulating,sandcontrolling,environmentalmonitoring,monitoringandpreventingofsecondaryformationofhydrateswereapplied.Thetestlastedfor60daysfromMay10^thwhenstartingtopump,droppressureandignitetowellkillingonJuly9^th,withgasproductionof3.09×10^5m^3intotal,whichisaworldrecordwiththelongestcontinuousdurationofgasproductionandmaximalgasyield.ThissuccessfultestbringsasignificantbreakthroughonsafetycontrolofNGHproduction.

  • 标签: Natural gas HYDRATE (NGH) Production test