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1.
1 Introduction Coagulationisanirreversible physical processinwhichanumberofbasicunits(monomers)sticktogeth ertobuildclusters.ThetimeevolutionofclusteringprocesscanbedescribedbytheSmoluchovskiequa tion[1 ],whichisd  Ckd t =12 ∑i j=kK(i,j)CiCj-Ck∑jK(j,k)Cj,(1)whereCkd…  相似文献   

2.
INTRODUCTIONColorectalcarcinoma (CRC)isoneofthemostcommonmalignancieswhoseincidencein creasesyearbyyearinChina (Fanetal.,1 993 ) .ThemoleculargeneticsofCRCisamongthebestunderstoodofcommonhumancancers.Thedevelopmentofcolorectalcarcinomainvolvesamultistageproce…  相似文献   

3.
浅议计算机辅助教学   总被引:1,自引:0,他引:1  
ComputerAssistedlnstruction (CAI)isthetermusedtodescribecomputerprogramsdesignedforteaching .ItisimportantnottoconfusethistermwithCALL(ComputerAssistedLanguageLearning)———thecatchalltermfordiffer entformsofL2instructionaccomplishedwiththeuseofcomputers.Fo…  相似文献   

4.
1 Introduction Withthedevelopmentofthe powerelectronicstechnology ,stationarypowerconvertingdevicessuchasAC DCconvertersandDC ACinvertersareappliedinvariousindustrialareas .However ,thishasledtosomeproblems ,e .g .theincreaseofharmonicsinpowersupply ,andtheEM…  相似文献   

5.
INTRODUCTIONInrecentyearsLChasbecomethemostcommontherapeuticmodalityforcholelithiasis.(Fruzee ,R .C .etal.,1 993 )ThefindingofCBDstonesbyintraoperativecholangiographyisthemajorreasonforresortingtoopencholecyc tectomy .ThisresearchwasdonetocomparecombinedLCandE…  相似文献   

6.
从一个例子谈起 已知△ABC的三个内角A、B、C满足 :A C =2B ,secA secC =- 2secB ,求cos A -C2 的值 .解 由A C =2B ,得A C =12 0° ,B =6 0° .∵ secA secC =- 2secB ,∴ cosA cosC =- 2 2cosAcosC ,2cos A C2 cos A -C2=- 2〔2cos2 A -C2 - 1 cos(A C)〕 ,即  4 2cos2 A -C2 2cos A -C2 - 32 =0 .因 - 324 <- 1,故解得cos A -C2 =22 .1 关于解题思维表现的分析上例中 ,条件是三角形三内角的一个关系式和有关这些角的一…  相似文献   

7.
InlinewithincreasingacademiccontactsandfriendlycooperationsbetweenChinaandGermany ,andsupportedbytheNationalNaturalScienceFoundationofChina (NSFC)andChinaPetrochemi calCorporation(SINOPEC)andtheGermanScienceFoundation ,thefirstChina GermanySympos iumonorga…  相似文献   

8.
1 Introduction IntheimplementationofCIMSinenterprises,thedevelopmentoftheCAD/CAMtechnologyandtheap pearanceofmatureCAD/CAMsoftwareprovidereliableandefficientdesigntoolsfortheexploitationanddevel opmentofproducts.UGII (aCAD/CAMsoftwareofEDScorporation)hasb…  相似文献   

9.
INTRODUCTIONItisveryimportantforChinatoachievesustainabledevelopmentbecauseoftheprimaryroleofChinaastheadvocateofpeaceintheworldandespeciallyintheAsiaPacificregion.OverthepastseveraldecadesChinahasincreasinglycometorealizetheTechnologicalInnovation(TI…  相似文献   

10.
我们把三边边长成等差数列的三角形叫做等差三角形.它有一个重要的性质如下:定理 在△ABC中,角A、B、C的对边分别为a、b、c,若a、b、c成等差数列,则有tgA2tgC2=13.证明 由题意知 2b=a+c,由正弦定理得 2sinB=sinA+sinC,∴ 4sinA+C2cosA+C2=2sinA+C2cosA-C2.又∵ sinA+C2≠0,则有2cosA+C2=cosA-C2,即 2cosA2cosC2-2sinA2sinC2=cosA2cosC2+sinA2sinC2,∴ 3sinA2…  相似文献   

11.
1 Introduction Beforemeltedaluminumalloyscanbecast,theymustberefinedtogetridofinclusions ,oxidesandsolvedhy drogen .Thewidelyusedrefiningmethodsrelyonad sorptiontechniques,suchasthetreatmentwithC2 Cl6 ,CCl4 ,ZnCl2 andN2 orArandsoon .Thegasbubblestookshapefromth…  相似文献   

12.
Definition LetWbeasubspaceofMn(C) ,then ordermatrixspaceoncomplexfield .IfAB =BA , A ,B∈W ,thenWiscalledacommutablematrixspace(CMS)ofMn(C) . AmongallCMSofMn(C) ,theremustexistaCMSwithmaximaldimensions,denotedbyW(n)max,andthemaximaldimensionsbyd(n)max.Theconstruction…  相似文献   

13.
Accordingtotherelateddata ,thetotalnumberofstudentsenrolledinthe 4 5 pilotuniversitiesinvolvedintheexperimentalworkofmoderndistanceeducationhasreachedmorethanfourthou sand .Asforthetechnologicalsupport ,theChinaCERNEThasrunfour 2 .5Glinesofthirty - fiveCERNETr…  相似文献   

14.
AComparativeStudyofSomeCommonEnglishandChineseMetaphorsGuoHongyiIntroductionItisgenerallybelievedthatOrientalcultures,suchasC...  相似文献   

15.
ReadingandReadingComprehensioninCET6YangYanhengTheFedbackCalingforCautionReadingcomprehensionsectioninColegeEnglishTestBand...  相似文献   

16.
Ⅰ  Communicationisnotanobjectwecanholdinourhand -itisanactivityinwhichweparticipate (Pearson ,1991) .Communi cationisusuallydevidedintotwoprimarycategories :verbalandnonverbal(Brooks ,1974 )intermsofitselements.Verbalcommu nication(VC)meanscommunicationwithlanguag…  相似文献   

17.
INTRODUCTIONMucunnewasthefirsttouseERCP (Endo scopicRetrogradeCholangiopancreatography)inthediagnosisofdiseasesofbileductsandpan creasin 1 968.Withimprovementofendoscopicequipment,thetechniquewasdevelopedrapid ly.TherearefewreportsintheworldontheuseofERCPfo…  相似文献   

18.
OnColegeEnglishClasroomResearchLinLiechengItisadecadesincethecaryingoutoftheCOLLEGEENGLISHTEACHINGSYLLABUS.Wearenowfacedwith...  相似文献   

19.
NomenclatureCAOconcentrationofsourcevapor,mol/m3DA(A=FCW,NCW,FCW)dimensionlessratesoffilmcoating,nucleationcoatingandtotalco...  相似文献   

20.
INTRODUCTIONTraditionalsilkproductsexportfromChinadominateworldsilkmarkets;totaled 4 2 .2bil lionUS$during 1 950 -1 998;andhaveasig nificantroleinChina’sforeigntradeandnation aleconomics.AfterChina’sdevelopmentofsericulturetechniquesandtheexpansionofpro ductionsc…  相似文献   

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