简介：分析了模具失效原因,结合工厂实际条件,因地制宜,对3Cr2W8V钢进行渗碳处理,提高了模具使用寿命,增加了工厂的经济效益.

简介：Threetypesofroughsurfacewereprocessedbylaserirradiationonthe3Cr2W8Vmaterialhot-workdiesteelsurface.Thewearexperimentswithsmoothsurfaceandroughsurfacesampleswererepeatedonthepin-traywearmachine.Accordingtothewearresults,westudiedtheregularityofwearresistanceofdifferentroughsurfacesamples.Theresultsindicatedthatbionicroughsurfacecanimprovethewearresistanceofthematerialandthewearresistancecanbeincreased1-2times,comparedwiththesmoothsurface.Also,thewearresistanceoftheroughsurfacewasaffectedbylasercurrentanddurationofimpulse.Thebiggerthelasercurrentortheimpulseduration,thebetteristhewearresistance.Whenthedistancebetweenthesamekindofunitswhicharedistributedonthesurfacesischanged,thewearresistancechanges.Thewearresistanceofabionicroughsurfaceonwhichthegridunitsweredistributedatspacingof1mmwasthebest.Andwedesignedthewearmodels.

简介：At-hyperwheel(t≥3)oflengthl(orW(t)lforbrevity)isat-uniformhypergraph(V,E),whereE={e1,e2,...,el}andv1,v2,...,vlaredistinctverticesofV=∪eii=1lsuchthatfori=1,...,l,vi,vi+1∈eiandei∩ej=P,j∈/{i1,i,i+1},wheretheoperationonthesubscriptsismodulolandPisavertexofVwhichisdifferentfromvi,1≤i≤l.Inthispaper,theminimumcoveringproblemofMCλ(3,W(3)4,v)isinvestigated.DirectandrecursiveconstructionsonMCλ(3,W(3)4,v)arepresented.Thecoveringnumbercλ(3,W(3)4,v)isfinallydeterminedforanypositiveintegersv≥5andλ.

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简介：“嘿，阳台上可以洗澡!”在三亚灼热的日光下忙活了一上午的摄影师王伟，回到酒店房间就兴奋地叫了起来。当我正琢磨在那用磨砂玻璃和木头围起来的小屋里洗澡是否“安全”时，他只裹了条浴巾就先冲进去了。

简介：摘要通过对W18Cr4V钢化学成分、组织及物理特性进行分析，制订出合理的加热、锻造操作、冷却工艺，减少了缺陷的产生，杜绝了废品。

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简介：某型号火药起动器壳体采用新材料1Cr11Ni2W2MoV,需要进行焊接工艺研究。针对此产品进行了自动TIG焊工艺试验,对比了S-659和HGH367两种焊丝以及不同焊接电流、焊接速度配合所焊焊缝的组织及性能。结果表明,采用S-659焊丝以及大电流高速焊的"大规范"的焊接参数所焊焊缝,成形、组织及性能均更优,焊缝质量满足QJ1842-95Ⅰ级要求。在此基础上进行了产品模拟件及正式产品的焊接,所焊产品经X光检查合格,液压、气密试验考核合格,满足使用要求。

简介：电视连续剧《请拔315》中曾出现过一道耐人寻味的难题:试设法将2+3=8变成一个等式。答案竟出乎意料简单——取一面镜子立于5+3=8(像)2+3=8之上(如图所——(反射镜)示),镜中的式子就是等式2+3=5(物)(5+3=8)。笔者观后,感想颇多,

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简介：一新以铁酸盐为主要成爬抵抗的钢被消除Nb并且与在高温度提高它的机械性质的目的把1.5集体%Re加到以铁酸盐为主要成的钢等级T/P23开发了。两钢，新等级和ASTMT/P的演员组铸块锭23，是热的在900点滚动了???眶?金瘵？？

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简介：摘 要：本文分析了1Cr11Ni2W2MoV钢中异金属夹杂物的性质，结合材料冶炼工艺过程的原始复查及分析研究，确定了产生异金属夹杂物的原因，提出了预防措施。

简介：TherearemanyprocessestoproduceCr2O3fromchrome-ores,DifferentparticlesizerangesofCr2O3powder,finepinmentgradegreenCr2O3andcoarsemetallurgygradeblackCr2O3,aremadebydifferentprocessesinChina,GreenCr2O3assuperfineandadditionandmetallurgygradeblackCr2O3usedtosynthesizeCr2O3graincanbeappliedtorefractories.ItisverydifficultforhighpurityCr2O3tosintertodensificationandTiO2additioniscontributedtodensificationofCr2O3sinteredathightemperature,Cr2O3grainswithrelativedensityof91%-95%aregainedbysinteringCr2O3withTiO2additionandelectrofusingCr2O3rawmaterials.

简介：ThecomplexK3H4GeW9V3O40·8H2OcrystallizedinamonocliiniesystemwithspacegroupP2,Mr=2784.67,a=11.099（3）,b=16.452（4）,c=13.534（4）,β=108.14°,Z=2,V=2348.493,F（000）:2456,μ=239.7cm-1,De=3.932g/cm3.ThefinalR=0.083for4528non-zeroreflexions.ThestructureofanionsGeW9V3O40andGeW9O34belongstoA--type.

简介：MgO-Al2O3-Cr2O3rammingmixesmadeofdifferentrawmaterialshavedifferentmineralstructureanddifferentphysicalpropertiesthoughwiththeidenticalparticlesizedistribution,thesameamountofbinderandchemicalcomposition.Theresidualcarboncontentofthefusedmagnesia-chromematerialmadeinreducingatmosphereisveryhigh,ifthismaterialsisusedintheMgO-Al2O3-Cr2O3rammingmix,itwouldcausespallingofthefurnaceliningduringdrying-out.

简介：Theeffectofbismuth（Bi）forbothVO2+/VO2+andV3+/V2+redoxcouplesinvanadiumflowbatteries（VFBs）hasbeeninvestigatedbydirectlyintroducingBionthesurfaceofcarbonfelt（CF）.TheresultsshowthatBihasnocatalyticeffectforVO2+/VO2+redoxcouple.Duringthefirstchargeprocess,BiisoxidizedtoBi3+（neverreturnbacktoBimetalinthesubsequentcycles）duetothelowstandardredoxpotentialof0.308V（vs.SHE）forBi3+/BiredoxcouplecomparedwithVO2+/VO2+redoxcoupleandBi3+exhibitno（orneglectable）electro-catalyticactivity.Additionally,therelationshipbetweenBiloadingandelectrochemicalactivityforV3+/V2+redoxcouplewasstudiedindetail.2wt%Bi-modifiedcarbonfelt（2%-BiCF）exhibitsthehighestelectrochemicalactivity.Usingitasnegativeelectrode,ahighenergyefficiency（EE）of79.0%canbeachievedatahighcurrentdensityof160mA/cm2,whichis5.5%higherthanthepristineone.Moreover,theelectrolyteutilizationratioisalsoincreasedbymorethan30%.Eventhecelloperatedat140mA/cm2forover300cycles,theEEcanreach80.9%withoutobviousfluctuationandattenuation,suggestingexcellentcatalyticactivityandelectrochemicalstabilityinVFBs.

简介：采用紧耦合气体雾化法制备Fe-13％Cr-3％W高温合金粉末，研究雾化气体压力和熔体过热度对粉末粒度及形貌的影响。结果表明，增加雾化气体压力和熔体过热度可以降低粉末的中位径，小于45μm和小于20μm粉末的收得率明显增加。粉末形貌均为球形，存在卫星结构粉末及不规则状粉末，雾化气体压力和过热度对形貌的影响不大。还分析了雾化参数对雾化过程及粉末粒度的影响机理。

简介：全新CR-V整车轮廓和现款差别不大，最大的改变是尾部，现款CR-V改掉了饱受诟病的“大翘臀”新车带来很强的层次感。东风本田CR-V采用全新设计的三辐式多功能方向盘，提供一键启动、双区空调、电子驻车、前／后排座椅电动调节．并配备HondaCONNECT智导互联系统，支持AppleCarPlay和AndroidAuto系统连接。

简介：无机化学实验中Cr2O3溶于浓硫酸的内容,其目的是试验并证明铬的氧化物的两性,接铬元素所在周期表的位置,其正常氧化物应能溶于酸和碱中,即属两性氧化物。对这一问题,我们查阅了有关资料,发现各有不同说法,计有下列三种不同叙述,一是载Cr2O3可溶于酸亦可溶于碱;二是载Cr2O3能溶于酸,但不溶于碱;三是载Cr2O3不溶