简介:本单元知识网络同步讲解SectionA1.Whatdoesyourfriendlooklike?你的朋友长什么样?询问某人的外貌特征常用:Whatdo/does+主语+looklike?……长什么样?—WhatdoesWangJunkailooklike?王俊凯长什么样子?—He’sreallytallandveryhandsome.他很高也非常帅。2.Shehaslongstraighthair.她有一头长直发。
简介:9,10-Phenanthrenequinone(PQ)andbenzilareimportantα-diketones.ThismanuscriptexplainsthefirstcomparisonofPQandbenzilmolecularproperties.Wehaveused1HNMR,13CNMR,1H-1HCOSY,HMBC,HMQC,UV-Visabsorptionandemission,CVandTGAexperimentstostudyPQandbenzilthatprovidedthefollowingnovelresults.(1)The1HNMR(CDCl3)ofPQshowδ8.19(H1),8.02(H4),7.72(H3),7.47(H2)insteadofanearlierreportedδ8.25(H4),8.08(H1),7.80(H2),7.55(H3);(2)inthe13CNMR(CDCl3),theC9/C10(C=O)signalofPQappearsupfield(δ180.3)comparedtoC9/C10(C=O)signalofbenzil(δ194.5),whichshowshigherelectrophiliccharacter(moreattractivefornucleophiles)ofC9/C10(C=O)ofbenzil;(3)thefirstλmaxfortheUV-VisabsorptionandemissionofPQareblue-shiftedcomparedtobenzildespiteincreasedconjugationattributedtothedifferentsymmetries(C2vforPQandC2hforBenzil)ofthetwomolecules;(4)theemissionspectrumofbenzilisbroadercomparedtothatofPQduetoslowerrelaxationoftheexcitedstate;(5)TheCVstudyshowsthatPQandbenzilaregoodelectronacceptorsandPQshowsabetterreductionprocessthanbenzilduetoanextraringthatprovidesstabilityforthereducedspecies(monoordiradicalanions);(6)TGAshowsthehigherthermalstabilityofPQthanbenzilattributedtothepresenceofphenanthreneunitinPQ.
简介:重点知识园地重点单词1.preparev.使做好准备;把……准备好Shewillpreparethefoodaheadoftime.她会提前准备好食物。短语(1)preparefor为……做准备Ican’tgotoyourpartybecauseIhavetoprepareforthemathtest.我不能去参加你的聚会了,因为我要为数学考试做准备。(2)preparesbforsth使某人对某事物有准备ShesaidsobecauseshewantedtoprepareTomforthenews.她这样说是为了让汤姆对这个消息做好准备。