简介:AseriesofCeB6-dopedandCeO2-dopedCa1-xSiAlN3:xCe3+(denotedasCASN:Ce3+@CeB6andCASN:Ce3+@CeO2,respectively)weresynthesizedbyalloy-nitridationmethodunderhigh-puritynitrogenatmosphere.Themorphologies,crystalphases,andluminescencepropertieswereinvestigatedindetail.WithanincreaseintheconcentrationofCeB6,theunitcellvolumeofCASN:Ce3+@CeB6slightlyincreasesduetothesubstitutionbetweenions,whichleadstoachangeofmicrostructurearoundCe3+.CASN:Ce3+@CeB6efficientlyemitsyellow-orangelightwithamaximumemissionintensityataround550nmforthecontentxof0.01(beingincomparablesituation,CASN:Ce3+@CeO2isx=0.04)whenexcitedat460nm.ComparedwithCASN:Ce3+@CeO2,theredemissioncomponentofCe3+inCASN:Ce3+@CeB6ismuchstronger.Thisisascribedtoenergytransferofintra-Ce3+(withinoneCe3+ion)andinter-Ce3+(betweenCe3+andCe3+ions).Inaddition,thereplacementsofN3-(0.132nmforCN=4)andO2-(0.124nmforCN=4)byB2-(0.140nmforCN=4),whichcanleadtoamarkedexpansionofthehostlatticeandadecreaseoftheoxidationofsamples,arealsoresponsiblefortheincreaseofredemissioncomponent.Furthermore,CASN:Ce3+@CeB6phosphorhasanexcellentthermalstabilitybecauseofthepartialsubstitutionofCe-O(Ce-N)bondsbymorecovalentCe-B.Asaresult,theoutstandingluminescentpropertiesofCASN:Ce3+@CeB6phosphormakeitpracticaltouseinthesinglephosphor-coatedhigh-color-renderingpowerwhiteLED.
简介:X-rayimagingistheconventionalmethodfordiagnosingtheorthopedicconditionofapatient.ComputerizedTomography(CT)scanningisanotherdiagnosticmethodthatprovidespatient’s3Danatomicalinformation.However,bothmethodshavelimitationswhendiagnosingthewholeleg;X-rayimagingdoesnotprovide3Dinformation,andnormalCTscanningcannotbeperformedwithastandingposture.Obtaining3Ddataregardingthewholeleginastandingpostureisclinicallyimportantbecauseitenables3Danalysisintheweightbearingcondition.Basedontheseclinicalneeds,ahardware-basedbi-planeX-rayimagingsystemhasbeendeveloped;itusestwoorthogonalX-rayimages.However,suchmethodshavenotbeenmadeavailableingeneralclinicsbecauseofthehightcost.Therefore,weproposedawidelyadaptivemethodfor2DX-rayimageand3DCTscandata.Bythismethod,itispossibletothreedimensionallyanalyzethewholeleginstandingposture.TheoptimalpositionthatgeneratesthemostsimilarimageisthecapturedX-rayimage.Thealgorithmverifiesthesimilarityusingtheperformanceoftheproposedmethodbysimulation-basedexperiments.Then,weanalyzedtheinternal-externalrotationangleofthefemurusingrealpatientdata.Approximately10.55degreesofinternalrotationswerefoundrelativetothedefinedanterior-posteriordirection.Inthispaper,wepresentausefulregistrationmethodusingtheconventionalX-rayimageand3DCTscandatatoanalyzethewholelegintheweight-bearingcondition.
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简介:摘要钢结构具有自重轻、抗震性能好、节能效果好、工业化程度高等一系列优点,被广泛的应用于火力发电厂,如果钢结构长期处于海洋大气、工业大气腐蚀环境下,会造成钢结构快速腐蚀,不仅浪费资源,同时也给结构安全带来隐患。锌加涂膜镀锌有效地结合了热镀锌锌层的主动阴极保护和有机涂料的屏障保护,对钢铁具有长效的优异防腐保护性能,特别适用于恶劣腐蚀环境下的钢结构防腐。但是锌加防腐施工对于钢结构表面处理,钢材表面盐分、粗糙度,喷涂工艺要求极为苛刻,受环境温度、空气湿度影响较大,现场施工难度较大。本文对“C5-M”腐蚀级别下钢结构锌加防腐施工技术进行了研究,为钢结构锌加防腐施工以及普通钢结构的喷砂防腐提供技术支持。
简介:Inpastyears,rare-earth-dopedfluoridefiberlasers(FFLs)havedevelopedrapidlyinthemid-infrared(mid-IR)region.However,duetothelackoffiberopticdevicesandchallengeoffluoridefibersplicing,mostmid-IRFFLshavebeendemonstratedwithfree-spaceopticelements,limitingtheadvantagesofall-fiberlasersforflexibledelivery,stability,andcompactness.Here,wereport,tothebestofourknowledge,thefirstpulsedall-fiberFFLinthemid-IRregion.Bytakingadvantageoftheintegrationofblackphosphorusflake,stableQ-switchedandmode-lockedpulseswereobtainedat2.8μmwavelength.Webelievethatthisall-fiberdesignwillpromotetheapplicationofpulsedFFLinthemid-IRregion.
简介:近年来,我国大力弘扬传统民族文化,龙舟竞技作为名族传统体育中重要的项目,其发展得到国家和社会广泛的支持及参与,中国龙舟协会在赛事的承办上,力度非常之大,赛事日益繁荣,职业组和大学生组的比赛充满竞争,其中大学生涌现如北华大学、江汉大学、聊城大学等实力强劲的队伍,在当地引起关注,旨在研究江汉大学男子龙舟队参加500m直道竞速的技战术,探究其中的规律和优势所在,为我校龙舟队训练、比赛提供较为科学的建议,以提升江汉大学男子龙舟队的整体竞争力。文章采用文献资料法、数理统计法、实验法等方法,分析和计算出江汉大学男子龙舟队500m竞速的各阶段桨频数,得出一些结论:起航划采用高桨频划法(在115桨/分以上),中途划采用中桨频(80桨/分-100桨/分),冲刺区采用中高的桨频(100桨/分-115桨/分)。今后的训练应围绕各阶段的衔接配合与桨频控制。