简介：AccordingtothenoticereleasedbyMIITandtheMinistryofNaturalResources,thefirstbatchofrareearthoreminingquotaswas60,000tonsin2019,ofwhichquotasforionictyperareearthmineral(mainlymediumandheavyrareearth)was9,575tons,andquotasforrocktyperareearthmineral(mainlylightrareearths)was50,425tons.

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简介：TheoverallreactionwasdeterminedonthebasisofthedissociationconstantofTBAandtheratiooftheligandtotherareearthioninthecomplex.Theratelaw,rateconstantsandacitivitionenergiesforthereactionofLa3+,Gd3+andHo3+withTBAwerestudied.ItisshowninthestudythatprerequisitesforperformingdifferentialrateanalysisforbinaryrareearthswithTBAarethatthepseudo-first-orderparallelreactionmechanismshouldbeconformedwith,nomultinuclearcomplexwouldbeformedandtheco-colorationeffectscouldbeneglected.

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简介：Whatisthepost-WTOera?ChinabecameonememberofWTOon10November2001,followedbyfiveyears'transitionalperiod.Post-WTOerashouldstartfrom2007afterthetransitionperiod.ChinabegantoissuemandatoryproductionquotasonREmineralproductssince2006andonREsmeltingproductssince2007,whichwasrightintheeraofthepost-WTO.REdemandandsupplysituationinthepost-WTOeraisanalyzedinthispaper,basedoncurrentstatusquoofChina'sREindustryandRE

简介：摘要：Google Earth现在无人不知，很多人在网上都可以查到自己家的房前屋后，这就是Google Earth的普遍性与实用性所在。Google Earth应用十分广泛，从最初的军用转为民用后我们生活的影像已经融入了这个小小的球体，有的人把自己家的小洋楼、旅游风景、产品广告、靓照发布到Google Earth上。Google Earth在生产技术领域也有广泛的应用，本文结合工作实际讲一讲其实用性。

简介：DrivenbycuriosityaboutpossibleflightoptionsfortheChang’e-2spacecraftafteritremainsattheSun-EarthL2point,effectiveapproachesweredevelopedfordesigningpreliminaryfuel-optimalnear-Earthasteroidflybytrajectories.Theapproachesincludetheuseofmodifiedunstablemanifolds,gridsearchofthemanifolds’parameters,andatwo-impulsemaneuverfororbitalphasematchingandz-axisbiaschange,andaredemonstratedtobeeffectiveinasteroidtargetscreeningandtrajectoryoptimization.Asteroidflybysareexpectedtobewithinadistanceof2×107kmfromtheEarthowingtotheconstrainedEarth-spacecraftcommunicationrange.Inthiscase,thespacecraft’sorbitalmotionissignificantlyaffectedbythegravitiesofboththeSunandtheEarth,andtherefore,theconceptofthe"heliocentricoscillating-Keplerorbit"isproposed,becausetheclassicalorbitalelementsoftheflybytrajectoriesreferencedintheheliocentricinertialframeoscillatesignificantlywithrespecttotime.Theanalysisandresultspresentedinthisstudyshowthat,amongtheasteroidswhoseorbitsarethemostaccuratelypredicted,"Toutatis","2005NZ6",or"2010CL19"mightbeencounteredbyChang’e-2inlate2012or2013withtotalimpulseslessthan100m/s.

简介：Theproblemsoftheearth'sgravityfields'visualizationarebothfocusandpuzzlecurrently.Aimingatmultiresolutionrendering,modelingoftheEarth'sgravityfields'dataisdiscussedinthepaperbyusingLODalgorithmbasedonQuadTree.First,thispaperemployedthemethodofLODbasedonQuadTreetodivideuptheregionalgravityanomalydata,introducedthecombinednodeevaluationsystemthatwascomposedofviewpointrelatedandroughnessrelatedsystems,andtheneliminatedtheT-cracksthatappearedamongthegravityanomalydatagridswithdifferentresolutions.Thetestresultsdemonstratedthatthegravityanomalydatagrids'renderingeffectswereliving,andthecomputationalpowerwaslow.Therefore,theproposedalgorithmwasasuitablemethodformodelingthegravityanomalydataandhaspotentialapplicationsinvisualizationoftheearth'sgravityfields.

简介：Thetetravalentmetalsaltsofmonoalkylphosphates[M(R-OPO3)2]areanewkindofstationaryphasesofchromatography-homogeneousbondedphases.Thestudiesonpreparation,structureandgaschromatographicefficiencyofceriumbis(octylphosphate)(COPP)arereportedinthispaper.Byusingchemicalanalysis,infraredspectra,x-raydiffractionanalysis,thestrongevidencethatCOPPhasalayeredstructureoftheα-zirconiumphosphatetypewasdemonstrated,therepetitiveunitisC8H17OPO3CeO3POC8H17andthereisalittlebendingorinterpenetrationofthealkylchainswithinthelayers.ThethermogravimeticanalysisoftheCOPPindicatedthatithasmuchmorethermalstabilitythansilica-basedpackings.ThethermodynamicparametersΔHandmolecularconnectivityindexesx′fortheadsorptionofseveraldozencompoundsontheCOPPhavealsobeendeterminedbygaschromatographicmethod,andthefinelinearitybetweenthemwasshown.

简介：In2018,undertheguidanceofPresidentXiJinping'sThoughtonSocialismwithChineseCharacteristicsforaNewEra,China'srareearthindustryhasmadesteadyprogresswithsignificantimprovementinoverallefficiency,aconstantimprovementinmanagementsystemandasteadyimprovementindevelopmentquality.

简介：Ininversemicroemulsion,rareearthferrite/polyacrylamidemagneticmicrospherewerepreparedandtheirmagneticresponsibilitywerestudiedbymagneticbalance.Resultsindicatethatthemagneticresponsibilityofmicrosphererelatestomagneticmomentofrareearthion,anditcanbeimprovedbytheadditionofdysprosiumionofhighmagneticmoment.Dysprosiumcontenthasaneffectonmagneticresponsibilityofdysprosiumferrite/polyacrylamidemagneticmicrosphere.ThemicrospheredisplaysstrongmagneticresponsibilitywhenthemolarratioofDy3+/ironis0.20.

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简介：人们第一次庆祝地球日始于1970年的春天。当时大约有来自世界各地的2000万人参加了那次集会，并使之成为美国环保活动的源头，并直接促成了一些国家法律如《净化空气及水质法案》的制定。到了1990年4月22日，在庆祝那次集会的20周年纪念日活动中，又有来自141个国家的两亿多人参加了那次活动。

简介：在这份报纸，理论免费triaxial地球摇摆被开发，新结论被得出：Euler时期应该被第一种完全的椭圆形的积分实际上表示；免费极的运动的踪迹是椭圆形的，它的半未成年者和主要的轴的取向分别地与地球主要的轴A和B近似平行。另外，现在的理论证明有在蜡烛制造者的频率振幅调整的机制摇摆，它可能是解释在蜡烛制造者的振幅和时期之间的关联的一个候选人摇摆。

简介：Chinesegovernmentattachesmoreandmoreattentionsonnewenergyvehiclesinrecentyears.Itseemsthatnewenergyvehicles,especiallyhybridvehicles,willreplaceconventionalfuelcarsinthefuture.Permanentmagnetmotorsandhybridcarbatteriesarethemostcrucialcomponentsfornewenergycarsandrareearthmaterialisakeytotheproductionofpermanentmagnetmotorandhybridvehicles.Therefore,it

简介：Thecopolymerizationofl-octenewithstyrenecatalyzedbyrareearthcoordinationcatalystshasbeenstudiedforthefirsttime.Somefeaturesandkineticbehavioraredescribed.Theoverallactivationenergyofthecopolymerizationwas22.2KJ/molandthecopolymerizationratecouldbeexpressedasRp=Kp[Nd][M]2.(=1.68×10-3L2/mol2.S,50℃,[Oct]/[St]=1).ThecatalyticactivityofvariousrareearthelementsinLn（naph）3forthecopolymerizationwascomparedandshowsthefollowingsequence:Dy,Y,Yb>Ho>Sm,Gd,Nd>Pr>Ce>La>Tm.Bothmonomersofl-octeneandstyreneinthecopolymerizationbyNd（naph）3-AlEt3havethetendencyofconstantproportioncopolymerization.Thestructureofthecopolymerswasstudiedby1H-NMR.

简介：Ⅰ.Mediabackground'Rareearth'hasbecomeahottopicgloballysince2009.TheTimesofUKpublishedanarticleentitled'Chinatakeschargeofkeystotechnologies'future'on9thMarch2009,inwhichChinawasconsideredtohavebecomethelargestmonopolycountryonrareearthmetals'supplyandtheleadingpositionwouldmakeChinacontrolthefutureofconsumerelectronicproductsandgreentechnology.Triggeredbythearticle,moreandmoreattentionswerepaidto'Chinarareearth'bymediainsideandoutsideChina.

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