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126 个结果
  • 简介:Grainsizeandmineralcompositionofcoresedimentswereusedtoinvestigateinfluencesofvariousterrestrialandmarineconditions,whichhaveprevailedonthesouthwesternBlackSeashelfduringtheHolocene.Siliciclasticmudwithsmallamountsofsandandgravelfromnearbycoastalhinterlandistheprincipalsedimenttype,whereassedimentsdepositedneartheshelfedgeandthe(I)stanbulStraitandofftheDuruLake(apaleo-rivermouth)constituedlargequantitiesofsandandgravelofbothbiogenicandterrigenicorigin.Variableamountsofaragonite,1nm-micas,quartz,feldspars,calciteanddolomiteconstitutethedominantnon-claymineralsinbulksediments.Theclaymineralassemblageinthe<2μmfractionismadeupofsmectite,illite,kaoliniteandchlorite.Aragoniteandcalcitearemainlyderivedfrombenthicaccumulations,whereasfeldspars(mainlyplagioclase)andsmectitereflectmagmaticvolcanicprovenanceandthedistributionof1nm-micasandchloritecorrelatewithnearbymetamorphicsourcesonland.Nevertheless,grainsizeandmineraldistributiongenerallyindicateacombinationofeffectsofwindandwaveclimate,longshoreandoffshorecycloniccurrents,changingsea-levelstandsandnearbysourcerockandmorphologicalconditions.ItisalsosuggestedthatatleastpartofclaymineralscouldbederivedfromthenorthwesterlyDanubeRiverinput.

  • 标签: 全新世 矿物 西南地区 土耳其 黑海 海平面
  • 简介:<正>我们都知道,black最基本的意思是“黑的,黑色的”,你可知道它还有其它的意思吗?其实,black的变身术是可以和MonkeyKing(孙悟空)相媲美

  • 标签: 黑人文化 BLACK SHEEP 布莱 前冲 克先生
  • 简介:不同尺寸的喷雾器被一个安德森空气刺绣花样收集观察黑碳(BC)的详细形态学与另外的伴随的喷雾器化学上被分开的喷雾器,用与一个精力DispersiveX光线分光计(SEM-EDX)装备的一台扫描电子显微镜。结果显示大多数BC喷雾器是在直径并且与同类的表面的大约50nm的球形的粒子。结果也证明这些粒子与另外的喷雾器或与自己一起聚集形成更大在测微计范围聚结。这些50-nmBC球形的粒子的形状被发现很类似于免除石油动力的车辆的内燃机的BCparticles的。这些球形的BCparticles被显示与发现帮助usingMatrix的激光解吸附作用/电离蒂米夫莱特·马斯·斯佩克特罗梅特里(MALDI-TOF-MS)的以前报导的fullerenes不同。

  • 标签: 大气粒子 纳米级颗粒 黑碳气溶胶 形态学 SEM-EDX
  • 简介:我们在场有在非线性的electrodynamics的宇宙论的经常的Λ的常规黑洞的一个班。而不是在黑洞地平线后面的平常的奇特,所有领域和弯曲invariants为常规黑洞到处是常规的。通过计量器不变的途径,常规黑洞的线性地动态的稳定性被学习。在odd-paritysector,我们发现Λ术语不出现在不安的主人方程,常规黑洞在奇怪同等值的不安下面是稳定的whichshows。在另一方面为平同等值的部门,没有宇宙论的常数,主人方程是比盒子更复杂的。我们为常规黑洞的稳定性获得足够的条件。我们也调查常规黑洞的热力学的性质,并且发现那些热力学的数量不满足黑洞热力学的第一条法律的微分表格。为违背第一条法律的原因被揭示。

  • 标签: 规则黑洞 稳定性 热力学 宇宙常量 非线性电动力学 扰动方程
  • 简介:Ultrasound(US)-inducedcavitationisaneffectivewayinoxidizingorganiccontaminantsinwastewatereitherastheindependentoperationunitorincombinationwithotheroxidationmethods.Inthispaper,blackliquorandfiltrateafteracidifyingandsettlingweresonicated.Theeffectofworkingparametersonultrasonicdegradationofblackliquor,suchasdifferentcombinationmethods,frequency,powersupply,initialconcentration,pH,durationtime,ionicstrengthandcatalystwerestudied.Theresultswereasfollows:(1)Attheconditionsof40kHz,100W,4h,pHat6andtemperature30±2℃,utilizingUS/US-H2O2/US-Fenton,weak-orangefiltrateturnedtocolloidwiththeincreaseoftimeandlittlesedimentproducedaftersettling.EspeciallyfiltratecametobemilkwhitecollidesandupperwaterapproachedtonearlyachromaticbyUS-Fenton.ComparedwiththeUS,US-H2O2/US-FentonCOD(Chemicaloxidationdemand)removalratiocanincrease15%,30%respectively.Becauseofmorehydroxylradicalsproducedinthereactionprocess;(2)Attheconditionof100Wand4h,thedegradationefficiencyofblackliquorwasbetterat40kHzoverat20kHz.Moreoverblackliquorcanbebiodegradedeasily.Thosebasedonthatthebigmoleculeofcontaminantsinaqueoussolutioncanbechangedintothelittlemoleculewithultrasound(3)Attheconditionof40kHzand4h,theCODremovalratioofblackliquorwasmorehigherat60Wthanat80W,whiletheremovalratioofCODat60Wwasnearlyclosetotheratioat100W;(4)Theinitialconcentrationofblackliquorinfluencedtheeffectofsonochemicaldegradation;(5)ThevariationofpHhadnoeffectondegradation;(6)Thelongerthedurationtime,thegreatertheremovalratioofCOD.Butthisratioincreasedslowlyafter4h;(7)Adding0.2g/LNaCltochangetheionicstrengthoftheblackliquor,theCODremovalratiocanincrease10%;(8)ThedegradationratesincreasedbythecoexistentcatalystsofTiO2,Co2+andAg+.

  • 标签: 降解反应 超声辐射 有机污染物 废水处理 黑色液体 化学需氧量
  • 简介:SighfertilitylevelinTibetZhangTianluDatafromthe1982and1990censusesinTibetshowthebirthrateinTibetandinaltheprefecturesoftheReg...

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  • 简介:Althoughvariousgenomeprojectshaveprovidedusenormousstaticsequenceinformation,understandingofthesophisticatedbiologycontinuestorequireintegratingthecomputationalmodeling,systemanalysis,technologydevelopmentforexperiments,andquantitativeexperimentsalltogethertoanalyzethebiologyarchitectureonvariouslevels,whichisjusttheoriginofsystemsbiologysubject.Thisreviewdiscussestheobject,itscharacteristics,andresearchattentionsinsystemsbiology,andsummarizestheanalysismethods,experimentaltechnologies,researchdevelopments,andsooninthefourkeyfieldsofsystemsbiology-systemicstructures,dynamics,controlmethods,anddesignprinciples.

  • 标签: 系统生物学 计算机模拟 基因组学 动力学
  • 简介:ThispaperexaminesthemotifofsurvivalinMasujiIbuse'sHiroshimanovelBlackRain(1969).Itexploresnarrativetechnique,figurativelanguage,voiceandtone,andthegapbetweenthoughtandfeeling,toshowhowthenovelachievesitsartisticeffects.

  • 标签: 日本 广岛 原子弹 小说 叙事技巧 《暴雨》
  • 简介:Abstract.WeobtainaBlack-Scholesformulaforthearbitrage-freepricingofEu-ropeanCalloptionswithconstantcoefficientswhentheunderlylngstockgeneratesdividends.TohedgetheCalloption,wewillalwaysborrowmoneyfrombank.WeseetheinfluenceofthedividendtermontheoptionpricingviathecomparisontheoremofBSDE(backwardstochasticdi~erentialequation[5],[7]).WealsoconsidertheoptionpricingproblemintermsoftheborrowingrateRwhichisnotequaltotheinterestrater.ThecorrespondingBlack-Sdxolesformulaisgiven.Wenoticethatitisinfacttheborrowingratethatplaystheroleinthepricingformula.

  • 标签: 股票市场 股票分红 BLACK-SCHOLES模型 期权定价公式 数学模型 数理统计
  • 简介:IntroductionErrorsareunavoidableinlanguagelearning,however,toagreatextent,teachersinmostmiddleschoolsinChinaregarderrorsasundesirable,asignoffailureinlanguagelearning.Mostmiddleschoolsarestillusingthegrammar-translationmethodwhichaimsatencouragingstudentstoreadscientificworksandenjoyliteraryworks.Theothergoalsofthismethodaretogainagreaterunderstandingofthefirstlanguageandtoimprovethestudents’abilitytocopewithdifficultsubjectsandmaterials,i.e.todevelopthestudents’minds.Thepracticalpurposeofusingthismethodistohelplearnerspasstheannualentranceexamination."Toachievethesegoals,thestudentsmustfirstlearngrammarandvocabulary,...Grammaristaughtdeductivelybymeansoflongandelaborateexplanations...studentslearntherulesofthelanguageratherthanitsuse."(TangLixing,1983:11-12)

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  • 简介:Whenpeopleadviseyourchildrento“getaneducation”,ifyouwanttoraiseyourpayment,theytellyouonlyhalfthetruth.Whattheyreallymeanistogetjustenougheducationtogivemanpower(人力)foryoursociety,butnotsomuchthatyouproveadifficultytoyoursociety.

  • 标签: 高中 英语 专项练习 参考答案 阅读理解题
  • 简介:Black-Scholes模型的基础上,通过改变B-S模型的基本假设,给出了几种基本的修正模型及定价公式.修正后的模型使得股票价格行为更接近现实市场的运作规律,从而更有实际意义.

  • 标签: 期权 B—S期权定价模型 股票价括 B—S方程
  • 简介:Selectionoftestcasesplaysakeyroleinimprovingtestingefficiency.Black-boxtestingisanimportantwayoftesting,anditsvalidityliesontheselectionoftestcasesinsomesense.Areasonableandeffectivemethodabouttheselectionandgenerationoftestcasesisurgentlyneeded.Thisletterfirstintroducessomeusualmethodsonblack-boxtestcasegeneration,thenproposesanewalgorithmbasedoninterfaceparametersanddiscussesitsproperties,finallyshowstheeffectivenessofthealgorithm.

  • 标签: 软件测试 黑盒子测试 界面参数 组合覆盖