首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
IntroductionThemostcommonmethodofyarnproductionistheinsertionofcontinuous ,unidirectionaltwistintoaparallelarrayoffibersorfilaments.Thehightorsionalstressesgeneratedinsuchaprocesshaveaconsiderableeffectonthestabilityandmechanicalcharac teristicsoftheya…  相似文献   

2.
Introduction  Towanttochangeisthebasiccharacterofhumanbeings.Colorchangesreflectamyriadofelementsfromdesignandsomecharacteristicssuchasfineart,aswellaseconomics,politics ,tra ditionalcultureandpsychologicalmoods.Inordertokeepupwiththechangingcolorandmak…  相似文献   

3.
TheexpressionofheterologousproteinsinEscherichiacolihasbecomeastandardtech niqueinmolecularbiology .E .coliexpressionsystemshavetheadvantagesofproductioneco nomicsandlogistics .TheseadvantageshavemadeE .coliexpressionsystemapopularchoicefortheproductionof…  相似文献   

4.
SinceWhiteobservedthatsprayingtobaccoplantswithsalicylicacid (SA)oracetylsalicylicacidinducedresistancetoinfectionwithtobaccomosaicvirus[1] ,manyexperimentshavedemonstratedthatSAplaysanimportantroleinplantdiseaseresistance ,actingasanendogenoussignalmolec…  相似文献   

5.
IntroductionAnonoscillatorysecondordercentraldifferenceschemeforhyperbolicconservationlawswasdevelopedbyNessyahuandTadmor[1](theNTscheme)fromthefirstorderLaxFriedrichs(LxF)scheme.IntheNTscheme,secondorderpiecewiselinearfunctionswereusedinsteadoffirstorde…  相似文献   

6.
IntroductionStarchisakindofnaturalpolysaccharidewidelyusedasrawmaterialinchemicalindustry .Withthedwindlingsuppliesofpetroleum ,theusageofstarchwidelyspreadsindifferentfieldsbecausestarch sabundanceandlowcost.Graftpolymerizationofsodiumacrylateontostarc…  相似文献   

7.
IntroductionFiber reinforcedcompositesareusedextensivelyinmanyweightcriticalapplications ,duetotheirhighspecificmodulus,highspecificstrength ,andthecapabilityofbeingtailoredforaspecificapplication .Thesematerialsofferdefiniteadvantagescomparedwithmostoft…  相似文献   

8.
Packingsandpackedcolumnsarewidelyusedinmanyprocessesinchemicalindustryandenvironmentaltechnology .Incontrasttoplasticandceramicmaterials ,stainlesssteelpackingsownadvantagesfortheirelasticityandfirmness.However,theirmasstransferperformancehasrecentlybee…  相似文献   

9.
Aschiefconstitutivecomponents,evergreenanddeciduousplants(especiallyevergreenanddeciduoustreespecies)playanimportantroleinthebiomassproductionofforests.However,theireffectsonforestproductivityarenottotallythesame,onecriticalreasonistheirsignificantp…  相似文献   

10.
IntroductionElectrolessNi Pplatingalloywhichbearsexcellentqualitiesofanti causticityandanti attritionhasabroadapplicationsintheindustryproduction Butinsomecases,itcannotgetgoodresultsbyusingonlyNi Pplatingalloyassurfacedefenseorconsolidationmaterials It…  相似文献   

11.
IntroductionLinearminimumvariancedstepaheadpredictorsaremostlypopularinmanyfieldsofapplication,suchasprocesscontrolprediction,adaptivecontrol,andeconomicprediction[1,2].Thispaperdiscussesthepracticeofcomputingcurrentpredictorformsandpresentsasetofrecursi…  相似文献   

12.
Forcenturies,therehasbeenaneverincreasinginterestinthenatureofreadingprocess,andmanyoftheseattemptstodescribetheprocesshavebeeninconflictwitheachother,whichmakesusreaderscon fusedinunderstandingandappreciatingatext,espe ciallyaliteraryone.Traditionall…  相似文献   

13.
Recently ,theresearchofartificialsuperlatticeshasbeenahottopicincondensedmatterphysicsandmaterialsfield .Before 1 984,researchworksonsuperlatticesweremainlyfocusedonperiodicstructures .Thediscoveryofquasicrystalhasopenedupanewfieldincondensedmatterphysicsa…  相似文献   

14.
IntroductionThedesireforanoptimaldiscretizationschemeremainsoneofthecriticalissuesincomputationalfluiddynamicsandnumericalheattransfer[1,2].Anoptimalschemepossessesaccuracy,stability:boundedness(nounphysicaloscillations)andalgorithmicsimplicity.Themaincon…  相似文献   

15.
Quantum Efficiency of Fluorescent Dyes and Color Matching   总被引:2,自引:0,他引:2  
IntroductionThetextilecoloristsusefluorescentdyestoachievecertainspecialeffects ,whichcouldnototherwisebeobtained .Sincefluo rescentdyeshavetheuniqueopticalpropertiesdifferentfromcon ventionaldyesandagents,thevariousdifficultiesareencounteredmainlyinflu…  相似文献   

16.
A Beam Search-based Algorithm for Flexible Manufacturing System Scheduling   总被引:2,自引:0,他引:2  
IntroductionSchedulingasanoperationsplanningproblemisconcernedwiththeallocationofresourcesovertimetoperformvarioustasks.Inaflexiblemanufacturingsystem (FMS)environment,schedul inggainsspecialimportanceduetothehighlevelautomationandconsiderationsofadditi…  相似文献   

17.
Agriculturalchemicalscanaffectphysiologyandbiochemistryofsoilmicrobesalthoughtheyundoubtedlyhavegreatbenefitsformodernagriculture .Previousstudiesontheeffectsofagriculturalchemicalsonsoilmicrobialcommunitieshavebeenmostlyfocusedonsoilrespira tion[1] ,soi…  相似文献   

18.
IntroductionNitricoxide(NO)usedtoberegardedonlyasatoxicgasmolecule .Nowit provesthatNOisamessengerinbiologicalsystematicsignaltransductioncascadesanditistheunique gassignalmolecule ,leadingtonumerousbiochemical,cellular ,andphysiologicalresponses .Especial…  相似文献   

19.
DI Shuo 《清华大学学报》1999,4(4):1620-1623
Thethroughputandresponsespeedofserverscanbeimprovedbyconnectingseveralcheapermachinesinalocalnetworkasacluster,actingasonepowerfulserverthroughtheparallelprocessing[1-3].Itischeaper,moreflexible,andmorereliable,hencemanyWebsiteshavealreadyinstalledWe…  相似文献   

20.
Interestisrapidlyemergingintheexplorationofmetalnanoparticlesforthedetectionofvariouskindsofmolecules.ExcellentexamplesincludeDNAdetectionbycomplimentaryinteractionsofthiol \|containingDNAattachedtogoldnano particles[1] ,potassiumionsensorsbyusing 15 crown …  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号