简介:摘要:在科学技术不断发展的时代中,计算机技术和通信技术以及微电子技术也随之发展起来,同时物联网技术也随着科技的发展而不断发展壮大,并且在各行各业中得到了广泛应用,比如说智能交通系统、公共安全、医学、农业以及工业等方面都是比较常见的。本文就是在物联网技术发展下,对窄带物联网技术的智能抄表系统进行了详细的介绍和分析。 关键词: NB-IOT ;远程抄表;智能电表
简介:K2NbOF5·H2OandK2TaF7werepreparedthroughmeltingNb2O5andTa2O5respectivelywithFHF2·2H2O,followedbyrecrystallizing.ThehydrolysispropertiesofK2NbOF5andK2TaF7weredeterminedagainbyusingarapidlyquenchvessel.Astemperature(from250to550℃)andpressure(from500to1500bars)increase,thedegreeofhydrolysisofbothK2NbOF5andK2TaF7willincrease.Nb-andTa-fluorinecomplexcompoundsareinstableinsupercriticalaqueousfluids.ThedegreeofhydrolysisofbothK2NbOF5andK2TaF7decreaseswithincreasingconcentra-tionofHF,independentoftheconcentrationofNaF.ThepartitioncoefficientsofNbandTabetweengraniticmeltandfluidphasearelessthan0.15,ie.,mostofNbandTaareleftingraniticmelt.ThepartitioncoefficientofTaismoredependentontheconcentrationofHFthanthatofNb.ThesignificanceofhydrolysisinNb-ansTamineralizationisalsodiscussedinthepresentpaper.
简介:CassiteritesfromboththeBeauvoirandMontebrasgeanitedofFrancearetypicallyrichintraceelementssuchasNbandTa,andcontainquiteanumberofinclusionsofcolumbite(dominantlymanganocolumbite).TwothinsectionsofcassiteritecrystalshavebeenpreparedforRamanmicroprobeanalysis).Thespectraobtainedfromdifferentpartsofthecassiteritesshowthatthevibra-tionfrequencyoftheA1gpeakdecreaseswithincreasingNb,Ta,FeandMnatomiccontents.Itisworthytonotethatanewpeak(namedthe“Anpeak”)hasbeenreportedforthefirsttimeinthepartwithorientedcolumbiteinclusions.Thevibrationfrequencyvariesfrom827to830cm^-1.ThepresenceofthenewpeakmaybeattributedtostructuralchangesofcassiteriteduetotheexcessofNbandTainthelatticeandtheexsolutionofcolumbiteinclusionsincassiterite.
简介:Tectonically,theareaunderstudyisknownastheSoutbeastChinaDiwaRegionwhicbbasexpcriencedthefollowingthrccstagesoftcctonicdeve1opment:l)thegeosynclinalstage,2)theplatformstage,3)thediwastage.Inthediwastagcandinitsmaximum-mobilitypcriodinparticular,tcctonicandisneousactivitieswcrestrong,extcnsive,ftcqucn