简介:privatizations have significantly increased market liquidity. And also privatization takes a potential role global capital market development. A. The Rise of Capital Market-Based Finance Capital market-based finance has in fact been increasing in importance,and the total capitalization of the US market increased almost nine-fold (from $ 1.9 trillion to $ 16.6 trillion) over the same period.c. The Dramatic Growth in Securities Issuance Volume Since 1990 Another way of measuring the rise of capital markets is to examine whether their share of annual corporate financing activity has grown relative to that of other sources of funding. Security offerings by US issuers accounted for two-thirds of the global total throughout 1990-1999,before more than doubling to $ 1.22 trillion in 1999--rivaling the US total. The global value of M%26A activity in 1999 reached $ 3.4 trillion
简介:Rare-earthcompoundsolidsuperacidSO42-/TiO2/La3+wasprepared.Itscatalyticactivitywasexaminedunderdifferentsyntheticconditionsfortheesterificationofpropanoicacidandn-butylalcoholasprobingreaction.Theoptimumconditionswerealsofound,whichwerethepH=8,thedepositingtimewas24h,themassfractionofLa(NO3)3usedinsolidsuperacidwas5%,theconcentrationofH2SO4was1.25mol/L,thesoakingtimeinH2SO4was16handthecalciningtemperaturewas500°C.TheethyloleatewassynthesizedfromoleicacidandethanolinthepresenceofSO42-/TiO2/La3+.Theoptimumreactionconditionswereobtainedwhichwerethereactiontimewas6h,molarratioofoleicacidtoethanolwas1:4andthemassfractionofcatalystwas4%.
简介:<正>1IntroductionTheundergroundbrineresourcesdistributingwidelyinSichuanBasin,Chinahavedrawnworldwideattentionduetotheirunusualelementabundanceandexcellentquality.
简介:TiO2nanoparticlesweresynthesizedbyahomogeneouscontrolledprecipitationmethodusingindustrialtitaniumsulfate(Ti(SO4)2).TheobtainedpowderswerecharacterizedbyX-raydiffraction(XRD),transmissionelectronmicroscope(TEM),Fouriertransforminfraredspectroscopy(FTIR)andICPplasmaspectrometer.EDTAwasusedascomplexingagenttoimprovethepurityandtheformationofTiO2nanoparticles.Experimentalresultsindicatedthatthehigh-purityTiO2nanoparticleswere20nminmeansizeandnearlymonodispersed.
简介:摘要:近年来,政府对危废渣的销售及排放管控越趋严厉,对露天排放及非法处置废渣的行为打击力度较大,地方政府、企业为了合理开发利用工业废渣,提高经济效益,保护环境,鼓励资源综合利用,化害为利,变废为宝。现根据我公司电石渣进行生料配料降煤耗减少SO2排放的实际进行研究,供大家参考。
简介:基于亚洲英语语料库和英国国家语料库,本文比较研究话语标记词so在英语通用语和英语本族语的特征。文章首先研究so在两个语料库中的分布频率,接着以Buysse的三大话语标记语元功能为框架,分析so在英语通用语语篇和本族语语篇中功能的异同。研究表明:1.亚洲英语通用语者使用so的频率较本族语者高;2.英语通用语者使用so的功能范围和本族语者相同;3.英语通用语者和本族语者在so的“充当提示词”“开启新话语序列”和“自我修正”功能上没有明显的区别,但是前者更多使用so的“标记结果”“标记结论”“占据话语权”“总结”“开启新话题”“回到未完成话题”和“修饰解释”等功能。本研究启示在教学中不应该把英语通用语视为是发展不完善的语言,再者,在学习话语标记语时除了关注狭义上的语义含义,还需要更关注其语用功能。
简介:本文研究了以TiO2-Sb2O3/SO4^2-为催化剂,催化假性紫罗兰酮合成紫罗兰酮。探索了反应温度、反应时间、催化剂用量、溶剂用量等因素对环化反应的影响。最佳合成条件:6mL假性紫罗兰酮,催化剂用量为1.8g,溶剂用量为6mL,环化反应温度为30℃,反应时间为3.0h,紫罗兰酮产率约为70%。
简介:One-potachievementofethyllevulinatefromcassavawasconductedinethanol-watersystemoverseveralsimplesulfatesaltcatalysts.Al2(SO4)3catalysthadthebestperformanceinsynthesizingethyllevulinatecomparingwiththoseofaseriesofsulfatesalts.Thehighestyieldsofethyllevulinatewasupto39.27%aswellas7.78%levulinateacidwhencassavawascatalyzedinethanolmediumbyadding10wt%water.13Cand1HNMRspectroscopicinvestigationsconfirmedthatisomerizationofglucosetofructoseoverAl2(SO4)3catalystisanimportantstepinproducingethyllevulinateandlevulinateacid.DuetoaggregationsofAl3+underhydrothermalconditions,tinyamountofAl3+weredetectedinfiltrateatthepercentageof0.32%evenifinabsolutewater.BronstedandLewisacidscouldimprovetheyieldofethyllevulinateandlevulinateacidbysynergisticeffect.AllresultssuggestedthatA12(SO4)3wasasimpleandefficientcatalystforethyllevulinateandlevulinateacidproduction.
简介:1IntroductionTherareearthcobaltalloyshavethepotentialformakingthemagneticandmagnetoopticalmaterials.Sofar,therareearthcobaltalloyfilmsaresubstantiallyproducedbysputteringorvacuumplating.Ifsuchfilmsarepreparedbyelectrodepositioninstead,productionefficiencywouldbeimprovedandthecompositionofthealloycouldbecontrolled.Becausetheoxidationreductionpotentialsofrareearthelementsareverynegative,organicsolventsmaybeusedaselectrolyticmedia.ElectrodepositionofGdCoandSmCoinorganicsolutionshasbeenreporte...