简介：摘要：某电厂屏式过热器管排夹持管管接头为T91/TP347H异种钢接头，运行50000小时后焊缝沿T91侧焊缝融合线断裂。通过对该焊缝两侧母材进行成分分析、金相组织分析及宏观检查。判断该焊缝断裂原因为长期运行后材料性能劣化导致失效。并针对此类问题提出有效检查方案及防范措施。

简介：为消除轴承钢中碳化物液析,改善碳化物带状,同时降低碳化物网状的级别,南钢在轴承钢的生产过程中,不断进行轴承钢加热温度、加热时间与碳化物溶解扩散情况的关系研究,寻找一条合理的加热温度和加热时间,提高南钢轴承钢质量水平。另外,南钢着手进行控轧控冷轧制,寻找低温轧制的途径和方法,降低碳化物网状级别,细化组织晶粒,使南钢轴承钢线材质量水平提升到一个新的高度。

简介：A(k;g)-graphisak-regulargraphwithgirthg.A(k;g)-cageisa(k;g)-graphwiththeleastpossiblenumberofvertices.Letf(k;g)denotethenumberofverticesina(k;g)-cage.Thegirthpairofagraphgivesthelengthofashortestoddandashortestevencycle.Afc-regulargraphwithgirthpair(g,h)iscalleda(k;g,h)-graph.A(k;g,h)-cageisa(k;g,h)-graphwiththeleastpossiblenumberofvertices.Letf(k;g,h)denotethenumberofverticesina(k;g,h)-cage.Inthispaper,weprovethefollowingstrictinequalityf(k;h-1,h)h),k≥3,h≥4.

简介：本文分上、下两部分。上部分谈本问题的提出和从数词／数字(oДИH／1)的读、写、译几方面来谈它的用法和意义；下部分谈oДИH的某些具体用法及与其有关的其他词的语法形式和用法，同时还涉及性、数、格等语法范畴及形式。

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简介：LetZbeatopologicalspaceandmappingA2:Z→B(H)withclosedrangeR(A2)becontinuous.SomenecessaryandsufficientconditionsofthecontinuityofM-PinversesAz+aregivenin[1],[2].ItisoneofthemthatAZ+iscontinuousifanaonlyifAZ+islocallybounded.Inthispaper,wediscussthefollowingproblem:iflimAn=A0inB(H)and||An+||isunbounded(i.e.theabovenecessaryandsufficientconditionfails),whathinHwillmaketheequations:limAm+h=A0+horw-limAn+h=A0+hbetrue.Forthispurposethreetheoremsandanerrorestimationaregiveninthispaper.

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简介：看了阿狸的《Z小姐的勇气》，我想起了那个少年的执着，对爱情的执着。少年姓何，我们就叫他H先生。他喜欢的女孩子姓林，我们就叫她L小姐。H先生与L小姐一起走过最美好的小学时光。从最懵懂无知的学前班到一起留级的二年级到轮廓线较清晰的六年级。别人的小学时光是六七年或更少，而他们却慢吞吞地走了八年，也就这样，我有幸跟他们同级。老师留级留得对。

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简介：上周港股在激烈震荡中走高，国企指数偏弱，拖累大盘。特别是周三A股市场急剧下挫，为近年来所罕见，A股全线走低，即刻影响到H股价格。目前中资上市企业市值已达港股的50％，A＋H两地上市更使港股联动增强。

简介：AseriesofNi-Hrechargeablebatterieswithatrademarkof‘JJJ’weresuecessfullydevelopedbyJiangnanTribleJcorporation,GuangdongProvince,andwereputintobatchproductionthisyear.ResearchonNi-HbatteryisoneoftheimportantprojectsinChina’sNationalHigh-TechProgramm.ScientistsinTribleJCorp.startedtheresearchlastyear.Afternearlyoneyear’sarduouswork,theycom-pletedthelabworkontheprojectandcametothe

简介：ThemixedH2/H∞guaranteedcostcontrolproblemviastatefeedbackcontrollawsisconsideredinthispaperforlinearsystemswithnorm-boundedparameteruncertainty.Basedonthelinearmatrixinequality(LMI)approach,sufficientconditionsarederivedfortheexistenceofguaranteedcostcontrollerswhihcguaranteenotonlyaprespecifiedH∞disturbanceattenuationlevelononecontrolledoutputforalladmissibleparameteruncertainties,butalsotheworst-caseH2performanceindexontheothercontrolledoutputtobenomorethanaspecifiedbound.Furthermore,aconvexoptimizationproblemisformulatedtodesignanoptimalH2/H∞guaranteedcostcontroller.

简介：HandoverinDigitalVideoBroadcastingforHandhelds(DVB-H)aimstoprovidecontinuousmobilebroadcastingserviceswhenauseristravelingthroughcellboundaries.Agoodhandovercontrolcanimprovethepowerefficiencyandgainmuchbetterreceptionquality.ThisletterprovidesanovelapproachforDVB-HhandoverbasedonDVB-H/UniversalMobileTelecommunicationsSystem(UMTS)hybridnetwork,whichmovesthemainhandoverfunctionfromtheterminalstothenetworks,sothatitreducestheoperationcomplexityoftheterminalsandincreasesthepowersaving.WhentheterminalcannotreceivetheDVB-Hsignalinthetransmissionshadowareasorbecauseofsomeotherreasons,theUMTSnetworksmayofferthesameservicetouserstomaketheservicecontinuous.AstheUMTSnetworkshavethetopologyoftheDVB-Hnetworks,bycommunicatingwiththeterminals,theUMTSnetworkscanhelptheterminalstopredictthehandover,andavoidunnecessaryhandover.

简介：5月15日，新哈弗H8正式上市，售价为18．38万-23．18万元。新哈弗H8播载“2．0T＋8AT”超强动力组合，并对外观、内饰进行重新设计，同时新增ACC自适应巡航、LDW车道偏离预警、AEB自动紧急制动等高安全科技配置。新啥弗H8还新增全地形控制系统与博格华纳双速TOD智能四驱系统，同时对底盘悬架进行重新调校，脱困性能、操控稳定性全面提升。

简介：AbstractWe conducted environmental surveillance to detect avian influenza viruses circulating at live poultry markets (LPMs) and poultry farms in Guangxi Autonomous Region, China, where near the China-Vietnam border. From November through April 2017-2018 and 2018-2019, we collected environmental samples from 14 LPMs, 4 poultry farms, and 5 households with backyard poultry in two counties of Guangxi and tested for avian influenza A, H5, H7, and H9 by real-time reverse transcription-polymerase chain reaction (rRT-PCR). In addition, we conducted four cross-sectional questionnaire surveys among stall owners on biosecurity practices in LPMs of two study sites. Among 16,713 environmental specimens collected and tested, the median weekly positive rate for avian influenza A was 53.6% (range = 33.5% - 66.0%), including 25.2% for H9, 4.9% for H5, and 21.2% for other avian influenza viruses A subtypes, whereas a total of two H7 positive samples were detected. Among the 189 LPM stalls investigated, most stall owners (73.0%) sold chickens and ducks. Therefore, continued surveillance of the avian influenza virus is necessary for detecting and responding to emerging trends in avian influenza virus epidemiology.

简介：摘要目的探讨产道血肿形成的原因和处理方法。结果主要症状为会阴部疼痛、坠胀，见于阴道两侧沟、会阴侧切处及其深部。多见于初产妇。以产后4小时特别是产后2小时即可发现并有明显症状。结论为预防产道血肿的形成，要加强产后观察，认真细致地进行阴道缝合。

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简介：近两年一档亲子真人秀节目《爸爸去哪儿》火爆荧屏。对节目中的萌娃们来说,生存就是找食材,只要伸手总能要到;生存就是卖水果、蔬菜,只要嘟囔一声就有买家蜂拥而至。然而在现实里,成长就如《魔女宅急便》中琪琪的修行,充满艰辛。这部由日本著名动画大师宫崎骏导演的动画电影改编自角野荣子的同名小说,是一个典型的少年成长故事,在宫崎骏诸多以主人公人格成长为主要叙事线索的影片中具有鲜明的代表性。

简介：引发核聚变反应的太阳中央部位温度高达1500万摄氏度。这些热向外传递，到太阳表面时已降到6000摄氏度左右。但是传到“日冕”，也就是包围太阳“光球”的大气时，又高达100万摄氏度以上。也就是说，从太阳中央向表面缓缓下降的温度，到了上层大气，竞急剧上升了100倍以上，这个现象是与太阳有关的最大谜团。6000摄氏度的光球如何能将日冕加热到100万摄氏度？

简介：“安乐死”是一个很敏感的话题,涉及到方方面面,对此众说不一。到目前为止除个别国家外绝大多数国家都采取谨慎或否定的态度。但是,随着社会的发展,人们的健康水平得到普遍提高,“生命的质量”逐渐成为现代社会人类追求的目标,由此引发大部分专家学者及越来越多的普通百姓对“安乐死”表示肯定。但他们也担心由此而导致的一些有关伦理道德方面的问题。那么考