简介：Inthepresentstudy,astatisticalinvestigationiscarriedouttoexplorewhetherthereisarelationshipbetweenthecriticalfrequency(foEs)ofthesporadic-ElayerthatisoccasionallyseenontheEregionoftheionosphereandthequasibiennialoscillation(QBO)thatflowsintheeast–westdirectionintheequatorialstratosphere.Multipleregressionmodelasastatisticaltoolwasusedtodeterminetherelationshipbetweenvariables.Inthismodel,thestationarityofthevariables(foEsandQBO)wasfirstlyanalyzedforeachstation(CocosIsland,Gibilmanna,NiueIsland,andTahiti).Then,acointegrationtestwasmadetodeterminetheexistenceofalong-termrelationshipbetweenQBOandfoEs.Afterverifyingthepresenceofalong-termrelationshipbetweenthevariables,themagnitudeoftherelationshipbetweenvariableswasfurtherdeterminedusingthemultipleregressionmodel.Asaresult,itisconcludedthatthevariationsinfoEswereexplainablewithQBOmeasuredat10hPaaltitudeattherateof69%,94%,79%,and58%forCocosIsland,Gibilmanna,NiueIsland,andTahitistations,respectively.ItisobservedthatthevariationsinfoEswereexplainablewithQBOmeasuredat70hPaaltitudeattherateof66%,69%,53%,and47%forCocosIsland,Gibilmanna,NiueIsland,andTahitistations,respectively.

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简介：1E题的背景与立意精明增长是一种城市规划理论,始于1990年代,是控制城市蔓延发展,减少城市中心周围农田损失的一种发展理念。为实现可持续发展,许多社区正在实施智能增长计划。精明增长的主要任务是促进城镇或城市的发展,使其经济繁荣,社会公平和环境可持续。

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简介：采用仪器分析方法和化学分析方法相结合测定三元前驱体Ni0.33Co0.33Mn0.33（OH）2中镍、钴、锰主含量,分别采用电感耦合等离子体原子发射光谱（ICP-AES）内标法测定镍、钴、锰的摩尔比例,EDTA滴定法测定镍、钴、锰的摩尔总量,计算得到各元素的含量。通过优化实验条件,进行了准确度和精密度实验,加标回收率为99.2%-101%,相对标准偏差小于0.65%。方法准确、快速,已用于实际的检测工作中。