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  • 简介:ThefruitsofPaulowniacatalpifoliaGongTongareusedasaChinesefolkherbalmedicineforthetreatmentofenteritis,tonsillitis,bronchitis,anddysentery,etc.OurpreviousstudyhasidentifiednewC-geranylatedflavanoneswithobviousanti-proliferativeeffectsinlungcancerA549cells.Inthepresentstudy,anewC-geranylatedflavone,paucatalinoneC(1)andfiveknownC-geranylatedflavanones(2-6)wereisolated.Inaddition,atotalof34C-geranylatedflavonoidsweredetectedbyHPLC-DAD-ESI-MS/MScouplingtechniquesfromtheCH_2Cl_2extractofP.catalpifolia.Futhermore,anti-agingeffectsofisolatedcompoundswereevaluatedinvitrowithprematuresenescent2BScellsinducedbyH_2O_2.PhytochemicalresultsindicatedthatP.catalpifoliawasanaturalresourceofabundantC-geranylatedflavonoids.Diplacone(3)andpaucatalinoneA(5)werethepotentanti-agingagentsintheprematuresenescent2BScellsinducedbyH_2O_2andtheC-geranylsubstituentmaybeanimportantfactorbecauseofitslipophiliccharacter.

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  • 简介:同步讲解SectionA1.Whattimedoyougotoschool?你什么时候上学?(1)whattime意为'什么时候,几点',常用来对具体的时间提问,可以用when替换。如:—WhattimedoesJimgotobed?吉姆什么时候睡觉?—Hegoestobedatteno’clock.他十点钟睡觉。

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  • 简介:患者1,女性,61岁。因"腹痛腹胀4天"于2014年2月6日急诊入院。患者下腹部疼痛剧烈,有恶心,无呕吐、腹泻、便秘等,肛门无排气、排便。查体示下腹部稍有压痛,无明显反跳痛,无肌卫,肠鸣音亢进(4次/分)。腹部X线示左中腹部小气液平面(图1A);腹部CT示肠系膜下动脉夹层,盆腔少量积液(图1B、1C)。心电图、血常规等其他检查未见明显异常。入院后患者皮下注射低分子肝素抗凝,硝酸甘油控制血压,同时予禁食、补液等对症治疗,3天后患者症状好转,逐渐过渡到半流质饮食后,于2014年2月15日出院。

  • 标签: 肠系膜下动脉 气液平面 肠鸣音亢进 下腹部 腹痛腹胀 半流质饮食
  • 简介:第一部分:听力、语音和词汇(25分)I.听力。(15分)第一节:听下面五段对话,每段对话后有一个小题,从题中所给的A、B、C三个选项中选出最佳选项。听完每段对话后,你都有10秒钟的时间来回答有关小题和阅读下一小题。每段对话仅读一遍。

  • 标签: 同步检测题 对话 听力 选项 词汇
  • 简介:摘要颅内静脉系统血栓形成(CVT)包括颅内静脉和静脉窦血栓形成,发病率较动脉性卒中明显低,但因病因复杂,解剖变异大,引流丰富,临床表现不典型,诊断有相当难度。随着磁共振等影像技术的进步,血管造影,如MRV和DSA的增多,颅内静脉系统血栓形成(CVT)的诊断增加。现就我院近两年来收治的颅内静脉系统血栓形成(CVT)2例患者的临床资料进行回顾,分析如下。

  • 标签: 颅内 静脉窦血栓
  • 简介:Hydrogen,thecleanestandmostpromisingenergyvector,canbeproducedbysolarintochemicalenergyconversion,eitherbythephotocatalyticdirectsplittingofwaterintoH2andO2,or,moreefficiently,inthepresenceofsacrificialreagents,e.g.,intheso-calledphotoreformingoforganics.Efficientphotocatalyticmaterialsshouldnotonlybeabletoexploitsolarradiationtoproduceelectron–holepairs,butalsoensureenoughchargeseparationtoallowelectrontransferreactions,leadingtosolarenergydriventhermodynamicallyup-hillprocesses.RecentachievementsofourresearchgroupinthedevelopmentandtestingofinnovativeTiO2-basedphotocatalyticmaterialsarepresentedhere,togetherwithanoverviewonthemechanisticaspectsofwaterphotosplittingandphotoreformingoforganics.Photocatalyticmaterialswereeither(i)obtainedbysurfacemodificationofcommercialphotocatalysts,orproduced(ii)inpowderformbydifferenttechniques,includingtraditionalsolgelsynthesis,aimingatengineeringtheirelectronicstructure,andflamespraypyrolysisstartingfromorganicsolutionsoftheprecursors,or(iii)inintegratedform,toproducephotoelectrodeswithindevices,byradiofrequencymagnetronsputteringorbyelectrochemicalgrowthofnanotubearchitectures,orphotocatalyticmembranes,bysupersonicclusterbeamdeposition.

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  • 简介:CO2capturewithionicliquids(ILs)hasattractedmanyattentions,andmostworksfocusedonabsorptionabilityatambienttemperatures,whileseldomresearchwasconcernedatelevatedtemperatures.ThisnotonlylimitstheCO2absorptionapplicationatelevatedtemperature,butalsothedeterminationoftheoperationconditionoftheCO2desorptiongenerallyoccurringathighertemperature.ThisworkmainlyreportedCO2solubilitiesinILsatelevatedtemperaturesandrelatedpropertieswerealsoprovided.1-alkyl-3-methylimidazoliumbis(trifluoromethylsulfonyl)imide([CnMIm][Tf2N])ILswereselectedasphysicalabsorbentsforCO2captureinthisworkduetotheirrelativehigherCO2absorptioncapacitiesandgoodthermalstabilities.Thelong-termstabilitytestsshowedthat[CnMIm][Tf2N]isthermallystableat393.15Kforlongtime.CO2solubilitiesin[CnMIm][Tf2N]weresystematicallydeterminedattemperaturesfrom353.15Kto393.15K.ItdemonstratedthatCO2solubilityobviouslyincreaseswiththeincreaseofpressurewhileslightlydecreaseswithincreaseoftemperature.Asthelengthofalkylchainonthecationincreases,CO2solubilityinILsincreases.Additionally,thethermodynamicpropertiesincludingtheGibbsfreeenergy,enthalpy,andentropyofCO2werealsocalculated.

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  • 简介:不同于那些急功近利的家伙,保时捷选择在美国拉斯维加斯E3电子娱乐展上发布了迄今为止最强悍的911车型911GT2RS,并且成功抢到了极限竞速7(ForzaMotorsport7)的游戏封面。虽然全新的911GT2RS基于997车型打造,但说它是997的终极性能版也不足为过。动力系统采用3.8L排量双涡轮增压发动机,但保时捷为这台发动机匹配了更大的涡轮增压器,使最高输出功率输出轻松达到515kW,如果用公制单位并不能令人产生什么异样的感觉,那么换成700hp这个说法,是不是就会有点恐怖了?它的峰值扭矩更是达到了750Nm。

  • 标签: 保时捷 涡轮增压发动机 电子娱乐 涡轮增压器 终极性 发动机匹配
  • 简介:传统的"暴力美学"是一种形式主义趣味,难免引起社会的道德担忧。《战狼2》作为一部公认的主旋律电影,受到了社会的肯定。该片打破了传统的"暴力美学"模式,以鲜明的道德和价值观判断,赋予了"暴力美学"新的内涵。

  • 标签: 《战狼2》 暴力美学 动作片 道德 价值观
  • 简介:Inthiswork,acidfunctionalizedmulti-wallcarbonnanotubes(MWCNTs)weremodifiedwithimidazolium-basedionicliquids.Theselectiveoxidationofvariousalcoholswithhydrogenperoxidecatalyzedby[PZnMo_2W_9O_(39)]~(5-),ZnPOM,supportedonionicliquids-modifiedwithMWCNTs,MWCNTAPIB,isreported.Thiscatalyst[ZnPOM@APIB-MWCNT],wascharacterizedbyX-raydiffraction,scanningelectronmicroscopy(SEM)andFT-IRspectroscopicmethods.Thisheterogeneouscatalystexhibitedhighstabilityandreusabilityintheoxidationreactionwithoutlossofitscatalyticperformance.

  • 标签: 多壁碳纳米管 离子液体 催化剂 多金属氧酸盐 氧化改性 H2O2
  • 简介:本文基于三轴磁阻传感器HMC5983设计了磁记忆检测探头,研制了基于USB2I2C控制模块的二维金属磁记忆检测系统,以45钢为试验对象开展了金属磁记忆试验研究。通过分析磁记忆二维分量以及其微分分量合成的李萨如图大小,确定试件中存在应力集中的严重程度,试验结果表明:磁记忆二维检测不仅能够准确定位试件中应力集中的部位,而且能够从梯度变化角度对应力集中严重程度进行预判评估。

  • 标签: 磁记忆检测 应力集中 李萨如图 定量评估
  • 简介:Co-electrolysisofCO2andH2Ousinghigh-temperaturesolidoxideelectrolysiscells(SOECs)intovaluablechemicalshasattractedgreatattentionsrecentlyduetothehighconversionandenergyefficiency,whichprovidesopportunitiesofreducingCO2emission,mitigatingglobalwarmingandstoringintermittentrenewableenergies.AsingleSOECtypicallyconsistsofanionconductingelectrolyte,ananodeandacathodewheretheco-electrolysisreactiontakesplace.Thehighoperatingtemperatureanddifficultactivatedcarbon-oxygendouble-bondofCO2putforwardstrictrequirementsforSOECcathode.Greateffortsarebeingdevotedtodevelopsuitablecathodematerialswithhighcatalyticactivityandexcellentlong-termstabilityforCO2/H2Oelectro-reduction.Thesofarcathodematerialdevelopmentisthekeypointofthisreviewandalternativestrategiesofhigh-performancecathodematerialpreparationisproposed.UnderstandingthemechanismofCO2/H2Oelectro-reductionisbeneficialtohighlyactivecathodedesignandoptimization.Thusthepossiblereactionmechanismisalsodiscussed.Especially,amethodincombinationwithelectrochemicalimpedancespectroscopy(EIS)measurement,distributionfunctionsofrelaxationtimes(DRT)calculation,complexnonlinearleastsquare(CNLS)fittingandoperandoambientpressureX-rayphotoelectronspectroscopy(APXPS)characterizationisintroducedtocorrectlydisclosethereactionmechanismofCO2/H2Oco-electrolysis.Finally,differentreactionmodesoftheCO2/H2OcoelectrolysisinSOECsaresummarizedtooffernewstrategiestoenhancetheCO2conversion.Otherwise,developingSOECsoperatingat300-600°CcanintegratetheelectrochemicalreductionandtheFischer-TropschreactiontoconverttheCO2/H2Ointomorevaluablechemicals,whichwillbeanewresearchdirectioninthefuture.

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