简介:Byusingthe40Ar-39ArchronologicalmethodtodateK-feldsparfromK-feldspargraniteintheQiaohuotecopperdistrict,theauthorsobtainedaplateauageof274.78±0.44Maandanisochronageof272.7±3.0Ma.BecausethereisnotectonicdeformationoverprintedorhydrothermalalterationintheK-feldspargraniteintrusionafteritsemplacement,the40Ar-39AragerepresentsthecrystallizationageofK-feldsparinK-feldspargranite,i.e.thelatecrystallizationageoftheK-feldspargraniteintrusion,whichindicatesthattheK-feldspargraniteformedintheintraplateextensionalstageduringtheEarlyPermian.Moreover,basedonthespatialrelationshipbetweentheK-feldspargraniteintrusionandcopperorebodies,variationsofcopperoregrade,REEcharacteristicsofK-feldspargraniteandcopperores,andHandOisotopiccompositionsoffluidinclusionsincopperores,themetallogenesisoftheQiaohuotecopperdepositisdirectlyrelatedtointrusiveactivitiesoftheK-feldspargranite,andthusthecrystallizationageofK-feldsparinthegraniteapproximatelyapproachesthemetallogenicepochoftheQiaohuotecopperdeposit.
简介:基于网络的现代远程教育的一种新的模式——虚拟大学正在对普及高等教育、提高国民素质以及实现终身学习等方面产生重大的影响,已引起不同领域专家以及各国政府的高度重视。我国基于网络的虚拟大学也有很大的发展.报报道,1999年我国仅有4所大学开始远程教育试点,在读学生最初只有7000多名,目前已发展到67所大学,共有学生130多万名。然而,各高校在构建虚拟大学时普遍存在的一个问题就是忽略了虚拟大学的虚拟化实验室的建设,使适种现代高等教育中速程教育的新模式得不到全面发展。为此,本文分析了虚拟大学的特征,比较了虚拟化实验室与传统实验室的区别,提出了创建虚拟化实验室的实施方案,以此来推动现代高等教育中远程教育的长足进展.
简介:Surfacemodificationofpolypropylenemembranebyargon(Ar)plasma-inducedgraftpolymerizationwithhydrophilicn,onomer[acrylicacid(AA)inthiswork]wasinvestigated.ItwasfoundthatboththedistanceofthemembranefromtheArplasmacenterandtheplasmapowerhadastronginfluenceonthesurfacemodification,hydrophilicityandgraftyield(GY)ofthetreatedmembrane.Resultssuggestthatremoteplasmatreatmentwithapropersampleposition,plasmapowerandgraftpolymerizationleadstoamembranesurfacewithnotonlylessdamage,bntalsomorepermanenthydrophilicity,thandirectplasmatreatmentdoes.Byanalyzingthemorphologyandthechemicalcompositionofthemembranesurfacebyscanningelectronmicroscopy(SEM)andX-rayphotoelectronspectroscopy(XPS),aswellasFouriertransforminfraredattenuatedtotalreflectionspectroscopy(FTIR-ATR)respectively,apossiblemechanismwastentativelyrevealed.
简介:摘要;目的通过动物实验从基因水平上研究中药复方对脾虚型AR的治疗机制。方法将健康SD大鼠随机分为7组。建立变应性鼻炎模型,用药七天后,检测大鼠IL-2mRNA,β1-DefensinmRNA等变化。结果用药七天后各治疗组的鼻部评分与模型组相比有差异(p<0.05)。IL-2mRNA,β1-DefensinmRNA表达脾虚AR组和AR组与空白组相比有显著性差异(p<0.01)。脾虚AR组与AR组相比有统计学差异(p<0.05);各治疗组与AR组相比有显著性差异(p<0.01)。结论中药能明显改善鼻粘膜病理反应;并通过多层次,多角度对细胞因子mRNA表达的调节,能起到很好的防治作用。
简介:ThispaperconstructsasetofconfidenceregionsofparametersintermsofstatisticalcurvaturesforAR(q)nonlinearregressionmodels.Thegeometricframeworksareproposedforthemodel.Thenseveralconfidenceregionsforparametersandparametersubsetsintermsofstatisticalcurvaturesaregivenbasedonthelikelihoodratiostatisticsandscorestatistics.Severalpreviousresults,,suchas[1]and[2]areextendedtoAR(q)nonlinearregressionmodels.