简介:Thegenerationofplasmawhichcanabsorbmicrowavesiscurrentlyaresearchtopicofinterest.Thiskindofplasmaisoftenproducedbythedischargeorelectron-beamimpactofnoblegases.Inthispaperanalternaticeapproach,combustionplasma,isstudied.Theplasmaisproducedbycombustingsolidgrainspreparedspecially.Sixgroupsofpowdersweremadeandusedtogeneratetheplasma.Thetransmissivityofthewaveinplasmawasmeasuredbyemployingamicrowavescalarnetworkanalysersystem.Inaddition,theelectrondensityandthecollisionfrequencyoftheplasmawereexaminedbymicrowavedouble-frequencydiagnosis.Themeasurementresultsshowedthattheplasmacouldabsorbmicrowavesremarkablywithanaveragetransmissionattenuationbeingmorethan18dBinafrequencyrangeof2GHzto15GHz.Thediagnosisindicatedthattheelectrondensityoftheplasmavariedfrom10~(17)m~(-3)to10~(19)m~(-3)andthecollisionfrequencywasabout5×10~(10)s~(-1).
简介:IntroductionAlthoughtheapplicationofmicrowavetechniquehasbeenreportedasanewtypeofenergysourcechemically,itisonlyinrecentyearsthatthistechniquehasbeenusedastheenergysourcefororganicsynthesis.In1986,R.Gedye,etal.,publishedthereportofthebenzoatesynthesisfromtherespectivereactionsbetweenbenzenecarboxylicacidandmethanol,propanolorbutanolundermicrowaveheatingandthecatalysisofH2SO4.
简介:Industrialapplicationofmicrowave,asaheatingsourceformaterialprocessing,wasreviewed.Thefeasibilityofcarbothermicreductionofzincoxideconcentrate,aswellastheeffectofoperatingparameterswasinvestigated,usingahomestylemicrowaveovenat2.45GHz.Zincoxideconcentratedoesnoteffectivelyabsorbmicrowaveenergy,whileanysourceofcarbon,whichisusedasthereductionagent,absorbsmicrowaveenergyverywell.Inthisrespectcokebreezewasfoundtobethebest,andthus,cokewasusedbothasthereducingagentandtheabsorbentofmicrowaveenergy.Itwasalsofoundthatanyincreaseinthecarboncontentandsize,increasesthereductionrate.Increasingthemicrowavepowerandthesizeofthesamplecouldalsoincreasethereductionrate.Furtherinvestigationshowsthatwhenzincoxideisexposedtothemicrowaveforsometime,therateofthereductionbyconventionalmethodincreases.
简介:与NOLM切换的微波photonic上的XPM的影响被能解决联合非线性的Schr的裂口步Fourier方法(SSFM)分析?dinger方程(CNLSE)。模拟结果证明XPM导致波形的失真和方面脑叶的漏缝。并且调整带宽越大,方面脑叶的漏缝是越多larger。而且,因为导致XPM的nonreciprocity,NOLMTm的力量传播功能被弄歪:当时,Tm减少couplerf鈭?的切开的比率0,0.5)并且增加什么时候f鈭?0.5,1)。CLC数字O451这研究被中国(号码60272048)的国家科学基金支持,为上海的优秀教师讲师的特殊科学基础。
简介:Theapplicationofmicrowavetechniqueinthehydrometallurgyofnickellateriteoreswasdescribed.Themixtureofnickellateriteoresandsulfuricacidwaspre-treatedbymicrowaveirradiation.Thedissolvingofnickelwasconductedinhotwaterattheatmosphericpressure.Theeffectsoffactors,suchasmicrowavepower,microwaveirradiationtime,andsulfuricaciddosage,wereinvestigated.Inmicrowavefield,themigrationofionicspeciesand/orrotationofdipolarspeciespromotetheliquid?solidreactionprocessduetotheincreasedcontactareaofreactantsandleachingreactionrateconstant.Thankstothestrengtheningactionofmicrowave,themicrowave-assistedleachingprocesshasitsadvantages,suchashigherextractingratethanconventionalatmosphericleaching,andnoneedforhigh-pressureoperationashighpressureacidleaching(HPAL).Theferricironinleachingsolutioncouldbeeffectivelyremovedbysodiumjarositeprocesswithalittlelossofnickelinthejarositeprecipitate.
简介:Inordertoimprovetheinterpretationoftheearthsystemmicrowaveremotesensing,theresearchofmicrowavespectrumcharacteristicsofthegroundtruth(earthobjects)wascarriedoutinlaboratory.Alaboratoryformicrowaveremotesensingoftheearthobjectshasbeenconstructedtoimprovetheremotesensinglevel,thelaboratoryconsistsoffourparts:themeasuringsystemofdielectricconstants,themicrowaveemissivitymeter,themicrowavereflectometerandthemicrowaveremotesensingsimulationexperimentinfield.Inthispaper,theprincipleofmeasurement,thecorrectionofnearfieldprocess,thestructureofinstrument,thecalibrationmethodandthemeasurementoftheearthsubstances,includingsoil,waterandoil,arediscussed.Thelabora-torymaysupplytheconditionformeasuringtheparametersofthcearthsubstanceremotesensingandhelptointerprettheremotesensingdata.
简介:Theenergytransmissionofthelongmicrowavepulseforthefrequencyof2.45GHzand5.8GHzisstudiedbyusingtheelectronfluidmodel,wheretheratecoefficientsarededucedfromtheBoltzmannequationsolvernamedBOLSIG+.Thebreakdownthresholdsfordifferentairpressuresandincidentpulseparametersarepredicted,whichshowgoodagreementwiththeexperimentaldata.Belowthebreakdownthreshold,thetransmittedpulseenergyisproportionaltothesquareoftheincidentelectricfieldamplitude.Whentheincidentelectricfieldamplitudehigherthanthebreakdownthresholdincreases,thetransmittedpulseenergydecreasesmonotonouslyatahighairpressure,whileatalowairpressureitfirstdecreasesandthenincreases.Wealsocomparethepulseenergytransmissionforthefrequencyof2.45GHzwiththecaseof5.8GHz.
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简介:Inthispaperweusea10-layerradiationtransfermodeltosystematicallyinvestigatetherelationbetweenbrightnesstemperatureandtherainfallratesat37GHz,includingvariousviewingofmicrowave(MW)remotesensinganddifferentsurfacecondition,withmainfocusontheinfluenceofthestructureofice-phaselayer.Theresultsshowthatthequantitativerainfallmeasurementcannotbereliablyobtainedoverthelandfromspuceborneradiometeratthiswavelengthandthestructuresoficelayerareveryimportantindeterminingthe"observed"brightnesstemperatureforthespaceborneMWremotesensing.
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简介:Multipaction,causedbythesecondaryelectronemissionphenomenon,hasbeenachallengeinspaceapplicationsduetotheresultingdegradationofsystemperformanceaswellasthereductionintheservicelifeofhighpowercomponents.Inthispaperwereportanovelapproachtorealizeaneffectiveincreaseinthemultipactionthresholdbyemployingmicro-poroussurfaces.Twomicro-porousstructures,i.e.,aregularmicro-porousarrayfabricatedbyphotolithographypatternprocessingandanirregularmicro-porousarrayfabricatedbyadirectchemicaletchingtechnique,areproposedforsuppressingthesecondaryelectronyield(SEY)andmultipactionincomponents,andthebenefitsarevalidatedboththeoreticallyandexperimentally.Thesesurfaceprocessingtechnologiesarecompatiblewiththemetalplatingprocess,andoffersubstantialflexibilityandaccuracyintopologydesign.Thesuppressioneffectisquantifiedforthefirsttimethroughtheproperfittingofthesurfacemorphologyandthecorrespondingsecondaryemissionproperties.Insertionlosseswhenusingthesestructuresdecreasedramaticallycomparedwithregularmillimeter-scalestructuresonhighpowerdielectricwindows.SEYtestsonsamplesshowthatthemaximumyieldofAg-platedsamplesisreducedfrom2.17to1.58fordirectlychemicaletchedsamples.MultipactiontestingofactualC-bandimpedancetransformersshowsthatthedischargethresholdsoftheprocessedcomponentsincreasefrom2100Wto5500Wforphotolithographypatternprocessingand7200Wfordirectchemicaletching,respectively.Insertionlossesincreasefrom0.13dBtoonly0.15dBforbothsurfacetreatmentsinthetransmissionband.Theexperimentalresultsagreewellwiththesimulationresults,whichoffersgreatpotentialinthequantitativeanti-multipactiondesignofhighpowermicrowavecomponentsforspaceapplications.
简介:Objective:Toinvestigatetheefficacyofcombina-tionofcircumcisionandmicrowaveongenitalwartsinuncircumcisedmen.Methods:Arandomized,prospectivestudyof109uncircumcisedadultmenwithgenitalwartswascon-ductedinaSTDclinicinZhanjiang,Guangdong.Onegroup(n=54)receivedmicrowavetherapyonly,whiletheothergroup(n=55)wastakenthecombinationofcircumcisionandmicrowavetherapy.Therecurrenceswereobservedattheendofmonths3,6and12,andoperativecomplicationswerealsorecorded.Results:Therewerenosignificantdifferencesinthemeanageanddurationofthediseasebetweentwogroups(P>0.05).Noseriousoperativecomplicationsweredocumented.Therecurrencerateincircumci-sionplusmicrowavegroupwasmarkedlylowerthanthatinmicrowavegroup(12.7%vs29.6%,P<0.05),whilethedifferencesinearlyandlaterecurrencesbetweentwogroupsshowednostatisticalsignificance(P>O.05).Conclusion:Circumcisioncanbesafelyperformedunderlocalanesthesiainanoutpatientsetting.Com-binationofcircumcisionandmicrowavecanproduceexcellenteffectaswellaslesstissuedamage,therefore,itmaybeidealforuncircumcisedpatientswithextensivecondvlomas.
简介:钕做了金轧镓氧化物(Nd:GGG)当燃料被报导,nanopowders用丙氨酸由微波胶化燃烧综合了。有丙氨酸燃料的金属硝酸盐答案是在微波的combusted给先锋。微波先锋粉末从800~1100°C在不同温度被锻烧。分阶段执行纯Nd:GGG形成在由X光检查衍射(XRD)和Fourier变换观察了的800~1100°C发生了红外线(FTIR)光谱学。然而,粒子尺寸在1100°C在800°C从25nm与锻烧温度增加了到200nm。Nd:在不同锻烧温度获得的GGGnanopowder被压缩并且在为在空中的3h的1550°C的sintered。最使增加密度陶器从Nd被获得:在1100°C锻烧的GGGnanopowder。从扫描电子显微镜学(SEM)观察了的微观结构证明大多数使增加密度陶器,从在更高的锻烧温度锻烧的nanopowder获得了,有更一致的谷物尺寸分布,更少毛孔和更大的densification。sintered样品的XRD显示出阶段纯净的保留。
简介:Desorptionofvolatileorganiccompounds(VOCs)frompolymericadsorbentsbymicrowavewasinvestigatedexperimentally.Twokindsoforganiccompounds,benzeneandtoluene,wereseparatelyusedasadsorbatesinthiswork.Resultsshowedthattheapplicationofmicrowavetoregeneratethepolymericadsorbentsnotonlycangethigherregenerationefficiencyincomparisonwiththeuseofheatregeneration,butalsomakethetemperaturesofthefixedbedsmuchlowerthanthatwhenusingtheheatregenerattonTheweakerthepolarityofapolymericadsorbent,theeasieritsregenerationwas.