学科分类
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303 个结果
  • 简介:【问27】-Don’tworry._________thievesthatdogsbarkat.-Maybe.Letusgooutandseewhathappened.

  • 标签: 高中 英语 课外阅读 教材
  • 简介:在几万年后,所有电影院都成了“高级”的。所谓高级就是所有电影都是ND效果(比什么3D呀,4D呀要好多了),这种ND效果的电影能让人百分之百进入角色.

  • 标签: 《ND电影院》 儿童文学 童话 姚欣雨
  • 简介:DefendingchampionsJapanshatteredChina'sdreamofafirsteverAsianCupfinalvictory,winningthankstoacontroversial(有争论的)goalinahostileatmospheretodownthehostnation3-1.ThoughweChineseteamdidn'twinattheend,thisisthebestresultwegotduringthepast20years.

  • 标签: 高中 英语 注释 足球运动 阅读练习
  • 简介:The22ndIASMeetingofSedimentologywasheldintheConventionCentreoftheGrandHotelAdriatic,inasmalltouristictownOpatija,locatedontheeasternAdriaticcoastwhereCentralEuropeandtheMediterraneanmeet.ItwasthesecondIASMeetingheldinCroatia--thefirstone,4thIASRegionalMeetingofSedimentology,washeldinSplitin1983.TheMeetinginOpatijawasorganizedbytheInstituteofGeology(Zagreb)andtheCroatianGeologicalSociety.ThesponsorwasMinistryofScienceandTechnologyoftheReoublicofCroatia.

  • 标签: 沉积学 油气盆地 互补训练 深海环境
  • 简介:TheatomicstructureofanovelrareearthcomplexconsistingofNdandthesulfur-containingligandpipdtc(C5H10NCS2^-)hasbeenstudiedwithextendedx-rayabsortpitonfinestructure(EXAFS)andx-raydiffractiontechniques.ThecomplexofformulaNd(pipdtc)4N(CH3)4crystallizaesinthemonoclinicspacegroupP21/nwiththefollowinglatticeparameters,a=22.685(2),b=20.332(2),c=17.1270(10)A,β=100.570(10)°.Z=8,thecalculateddensityis1.47g/cm^3,Anewderivativemethodisusedtoremovethepiost-edgeabsorptionbackgroundincludingthemultielectronexcitationeffect.TheEXAFSresultsdemonstratethatthereareabouteightSandfourOatomsaroundNdwiththeNd-Sbondlengthof2.916AandtheNd-Obondlengthof2.415A,respectively.Thisimpliesthatthepowderofthiscomplexisnotstableandiseasytooxidizeinair.Thepossiblechangeofstructurebeforeandafteroxidationisdiscussed.

  • 标签: 二硫代氨基甲酸盐 钕有机化合物 原子结构
  • 简介:The2ndMid-EuropeanClayConference(MECC'04)washeldbetween20-24thSeptember2004,inMiskolc,Hungary.Theideatoholdcommonconferenceswasacceptedbythenationalclaygroupsoffourneighbouringcountries,Poland,Slovakia,HungaryandCroatia,duringtheEUROCLAYMeetinginCracow,Poland,in1999.Thefirstconferencewasheldin2001atStaráLesná,intheHighTatraMts.inSlovakia.

  • 标签: 欧洲 粘土 地质学会议 学术成果 土壤科学
  • 简介:ThesecondCulturalFestivalofYiClothingwasheldinZhaojueCounty,SichuanProvince,fortwodaysstartingonMay4,displayingtheprocessesinmakingtheattireoftheYipeople,includingthetechniques

  • 标签: 文化节 彝族 服装 四川 ND 文化遗产
  • 简介:Yttriumaluminumgarnet(YAG)transparentceramicswerefabricatedbysinteringatoxygenatmosphere.Tetraethylorthosilicate(TEOS)wasaddedasthesinteringadditivetocontrolthegraingrowthanddensification.Poreswereeliminatedclearlyattemperaturelowerthan1700oC,whilegrainsizewasaround3μm.Thein-linetransmittancewas80%at1064nmwhensamplesweresinteredat1710oC.TheeffectofTEOSwasstudiedinoxygenatmospheresinteringforNd:YAGtransparentceramics.Athighertemperaturelike1710oC,thegraingrowthmechanismwassolutedrag,whileat1630and1550oCthegraingrowthwascontrolledbyliquidphasesinteringmechanism.And0.5wt.%TEOSwasthebestaddingcontentforNd:YAGsinteredinoxygenatmosphere.

  • 标签: Nd YAG陶瓷 烧结助剂 氧气氛 晶粒生长 TEOS
  • 简介:针对Nd:GGG激光器,介绍了荧光寿命测试原理,设计了低频窄脉宽荧光寿命测试系统。该系统由光源、光路系统、驱动电路和探测系统等几部分组成。利用脉冲取样技术测试了Nd:GGG晶体的荧光寿命约为250μs左右。

  • 标签: Nd:GGG晶体 荧光寿命 脉冲取样技术 低频窄脉宽
  • 简介:AIM:Toinvestigatetheeffectsofanewopeningpatterninneodymium:yttrium-aluminum-garnet(Nd:YAG)laserposteriorcapsulotomyonvisualfunction.METHODS:Thistechniquewasconductedalongacircularpattern.Theenergyrangedbetween0.8and1.2mJ/pulsewasconsumedandmeantotalenergylevelswere74±21mJ(mean±standarddeviation:SD,from40to167)andlasershotsaimedat150μmawaybehindadatumpointandwentalonganimaginarylinewhichextends0.5mminsidefromopticmarginandintothecircularenblocpattern.Vitreousstandswereattachedwithfragmentandthentheywerecutoffbythelaseraftercircularapplication.Thecircularfragmentwascompletelyseparatedfromvitreous,andthenthisfragmentwasquicklysunkinintravitrealspace.RESULTS:Thefollow-upperiodrangesfromatleastaweekto40mo,making15.8moonaverage.Theproceduraloutcomeshowed96%(74eyesoutofthe77eyes)enhancementinpatients’visualacuity.Cystoidmacularedemaorretinaldetachmentwasnotobservedinanyofthepatientsduringfollow-upperiods.CONCLUSION:Thisnewtechniqueisexpectedtoimprovetheweaknessesthattheconventionalprocedureshavebyaddingtheprocesstocutoffvitreousstandsattachedwiththefragmentbythelasertothecircularapplication.

  • 标签: CATARACT INTRAOCULAR lens damage POSTERIOR CAPSULAR
  • 简介:钕做了金轧镓氧化物(Nd:GGG)当燃料被报导,nanopowders用丙氨酸由微波胶化燃烧综合了。有丙氨酸燃料的金属硝酸盐答案是在微波的combusted给先锋。微波先锋粉末从800~1100°C在不同温度被锻烧。分阶段执行纯Nd:GGG形成在由X光检查衍射(XRD)和Fourier变换观察了的800~1100°C发生了红外线(FTIR)光谱学。然而,粒子尺寸在1100°C在800°C从25nm与锻烧温度增加了到200nm。Nd:在不同锻烧温度获得的GGGnanopowder被压缩并且在为在空中的3h的1550°C的sintered。最使增加密度陶器从Nd被获得:在1100°C锻烧的GGGnanopowder。从扫描电子显微镜学(SEM)观察了的微观结构证明大多数使增加密度陶器,从在更高的锻烧温度锻烧的nanopowder获得了,有更一致的谷物尺寸分布,更少毛孔和更大的densification。sintered样品的XRD显示出阶段纯净的保留。

  • 标签: 纳米粉体 燃烧合成 GGG 微波 烧结 凝胶
  • 简介:TheSecondChinese-SovietSemi-naronChemistryandApplicationsofRareEarthswasheldinChangchunandShanghai,China,fromOct.4thto14th,1991.Nearly100scientistsandexpertsparticipatedinthemeetingand98paperswereintoconferenceproceedings.ThemeetingwasjointlychairedoverbyProf.NiJiazuanofChang-chunInstituteofAppliedChemistry.AcademiaSinica.and

  • 标签: jointly PROCEEDINGS SEMINAR SINICA SEMINAR visited
  • 简介:Magnetizationanddemagnetizationcurvesandhysteresisloopsapplieddifferentmagnetizing.fieldsinsinteredNd-Fe-BandNd-Dy-Fe-Bmagnetsfromthermallydemagnetizedanddcfield-demagnetizedstateswereinvestigatedattemperaturesofupto150℃.Thefirst-quadrantremagnetizationcurvesandthecurvesofcoerciveforces_MH_CversusrernagnetizingfietdsH_mfromdcfield-demagnetizedstateatroomtemperatureshowasteparoundmagnetizingfieldasabsolutevalueofthemaximumintrinsiccoercivity.Thestepsof_MH_C-H_mcurvesshiftedtolowerremagnetizingfieldsandtheshapesofmagnetizationcurveschangedfromsteptypetoprecipitoustypewhentemperaturewentupto100~150℃orafterthespecimenwasthermallydemagnetizedatatemperaturehigherthantheCurietemperature.Thesteepriseofkneecoereivitywithincreasingmagnetizingfieldisbehindthatof_MH_C.NotethatthemagnetichardeninginsinteredNd-Fe-Bmagnetsiscontrolledbypinningofdomainwalls.

  • 标签: MAGNETIZATION COERCIVITY thermally HYSTERESIS ABSOLUTE walls
  • 简介:Aneodymiumdopedyttriumaluminumgarnet(Nd:YAG)transparentceramicwasfabricatedbyasolidstatereactionmethodusingcommercialα-Al2O3,Y2O3,andNd2O3powdersasstartingmaterialsandtetraethylorthosilicate(TEOS)assinteringaid.ThemorphologyandmicrostructureofthenanopowdersandtheNd:YAGtransparentceramicwereinvestigated.ThefullydenseNd:YAGceramicwithanaveragegrainsizeof~20μmwasobtainedbyvacuumsinteringat1720°Cfor12h.Fewporesandgrain-boundaryphaseswereobserved.Thein-linetransmittanceoftheceramicwas81.5%at1064nm.

  • 标签: ND:YAG陶瓷 光学性质 Nd:YAG激光 正硅酸乙酯 制作 ND:YAG
  • 简介:Fortheestablishmentofdirectrevascularicationoftheischemicmyocardium,aNd:YAGlaserwithawavelengthof1060nmandanopiticfiberdiameterof500umwasusedtocreate20to25transmuralchannelsinthecentralischemicregionoftheleftventricleafterthecoronarywasligatured.Thechannelswerecreatedfromtheepicard1alsurfacetotheendocardiumandeachchannelreceivedabout64joulesofthe

  • 标签: LASER created MYOCARDIUM VENTRICLE branch DESCENDING