简介:Thedifferencesofreductionbehaviorsbetweenironorelumpandpelletswerestudiedbyconductinglowtemperaturereductiondegradation,staticloadreductionanddroplettests.Thesetestssimulatedtheconditionsofreductiontemperatureandhydrogen-containinggasinCOREX.Duetoitsdensestructureandlowporositycomparedwithpellets,lumporepossessespoorreductiondegradationindex(RDI)andslowerreductionrateinearlyandmediumreactionstages,showingsignsoflowerstrength,lowersofteningandmeltingtemperatures,aswellasawidermeltingzoneandhigherΔP.Thatprovidessomebasistoexplainthephenomenaofdifferentialpressurerise,metallizationdeclineandmorestickingaftertheusageoflumporeinCOREXplant.
简介:W.H.奥登作为对穆旦、杜运燮等西南联大诗人有重要影响的英国诗人,其对于中国现代主义诗歌形成与发展的重要意义已然为学界认可,但奥登的诗歌除了“机智”、“俏皮”等特点为部分学者注意之外,其丰富的诗歌特质仍未得到充分关注。对于深入解读西南联大诗歌群体的文学创作活动而言,接近“真实”的奥登就显得至关重要。在那个特殊的历史情境中,威廉·燕卜荪的引介无疑是联大诗人们认识奥登的最初途径——燕卜荪对奥登的介绍,不仅仅让这些联大诗人们认识了英国现代主义诗歌,而且直接引发了西南联大现代主义诗歌的创作实践,使中国的现代主义诗歌纳入了世界现代主义文学创作的格局,并对中国当代的诗歌创作产生着重要影响。
简介:摘要简述磁共振波谱(MRS)的基本原理及其在乳腺病变检查中所要获得理想信息、图像的技术要求,总结了乳腺肿瘤的MRS特征,并与其生化病理特性相联系。本文综述目前MRS在乳腺癌的临床应用概况、获得满意图像的技术因素、及今后要改进的方面,以能更好地应用于临床。
简介:合成了一个新的配合物,经元素分析及X-射线衍射对其结构进行了表征.化合物晶体属单斜晶系,P2(1)/c空间群,晶胞参数:a=6.4824(13),b=6.1325(12),c=19.980(4),α=90°,β=91.925(2)°,γ=90°,V=793.8(3)A3,M=245.05,Z=4,Dc=2.050Mg.m-3,F(000)=492,吸收系数μ=1.671mm-1,最终偏离因子R1=0.0263,wR2=0.0692.化合物的分子结构存在一维链状的结构,由于复杂氢键的存在,它的堆积结构呈二维网状排列,而且在[010]方向看到了纳米空洞.
简介:Twooxo-vanadium(IV)complexes,[VO(C2O4)(2,2′-bipy)(H2O)]·C2H5OH(1)andVO(C2O4)(phen)(H2O)(2),where2,2′-bipy=2,2′-bipyridyl,phen=1,10-phenanthroline,weresynthesizedaspotentialfunctionalmodelsofvanadiumhaloperoxidases(VHPOs)inmixedsolventofethanolandwateratroomtemperature.Thecomplexeswerecharacterizedbyelementalanalysis,infrared(IR),UV-VisandX-raycrystallography.Structuralanalysesshowedthatvanadiumatomwascoordinatedbyaterminaloxygen,oneoxygenatomfromcoordinatedwater,twooxygenatomsfromthecarboxylategroupofoxalicacid,andtwonitrogenatoms(N1andN2)from2,2′-bipy/phen.Centralvanadiumatomsincomplexes1and2werebothinadistorted-octahedralenvironment,andsomeintermolecularhydrogenbondinglinkageswerealsoobservedineachcomplex.BrominationreactionactivityofthetwocomplexeswasevaluatedwithphenolredasorganicsubstrateinthepresenceofH2O2,Br-andphosphatebuffer,indicatingthattheycanbeconsideredasapotentialfunctionalmodelofVHPO.Inaddition,thermalanalysiswasalsoperformedanddiscussedindetail.
简介:设p是适合p≡1(mod6)的奇素数.本文运用Pell方程的基本性质证明了:如果p=3r2-2或者3p=r2+2,其中r是正整数,则方程x3-1=3py2无正整数解(x,y).根据上述结果可知:当p〈100时,该方程仅当p=37时有正整数解(x,y).