简介:随着高频通信技术的不断发展,高频特种印制电路板的需求越来越多。聚四氟乙烯(PTFE)材料以其良好的耐高温耐老化以及低损耗而著称,是目前用量最大的高频特种印制板类型。但由于PTFE材料独特的物理化学性能,导致其机械加工难度大。在钻孔过程中,如果钻孔参数设置不当,极易出现孔壁粗糙、铜瘤等不良问题。本文选用业内常用的PTFE+玻璃布和PTFE+玻璃布+陶瓷填充两种类型的材料,通过正交试验方法,对其钻孔参数进行分别进行分析和研究,从而得出最优的参数组合,有效解决了PTFE材料在钻孔过程中产生的孔壁粗糙、铜瘤等不良问题,为业内同行加工PTFE材料提供参考。
简介:Thedevelopmentofthehydrogenelectrodeisvitalfortheapplicationofalkalinepolymerelectrolytefuelcells(APEFCs).Inthisstudy,aseriesofNi(OH)2decoratedNi/Ccatalysts(Ni(OH)2-Ni/C)werepreparedbyathree-stepelectrochemicaltreatmentofNi/C.TheexistenceofNi(OH)2wasdemonstratedbyX-rayphotoelectronspectroscopy(XPS),andthesurfacemolarratioofNi(OH)2/Niofthesampleswasestimatedviaanelectrochemicalmethod.TheHORcatalyticactivityofthecatalystswasevaluatedbyarotationdiskelectrode(RDE)method,anda'volcanoplot'wasestablishedbetweentheHORexchangecurrent(j0)andthesurfacemolarratioofNi(OH)2/Ni.Ontopofthe'volcano',thesurfacemolarratioofNi(OH)2/Niis1.1:1,thej0ofwhichwas6.8timesofthatofNi/C.ThestabilityofthesamplestowardHORwasevaluatedtobegood.OurstudyaddedasystematicexperimentalevidencetotheHORresearch,showingthattheHORcatalyticactivityofNicanbedeliberatelycontrolledviadecorationofNi(OH)2,whichmayhelpunderstandingtheHORmechanismonNi.
简介:Theinterfacialbindingcovalentbonddensity(CBD)andthelocalenvironmentaltotalbondorder(LTBO)oftheNi/Ni3Alinterfacewithdifferentlatticemisfits(δ)werecalculatedbyusingfirst-principlesdiscretevariationXαmethod.ItwasfoundthattheeffectsoflatticemisfitsontheelectronicstructuresofincoherentNi/Ni3Alinterfacewereveryobvious.Ononehand,lessthan-0.6%negativelatticemisfitcanpromotethebindingstrengthofγ/γ′interface.Ontheotherhand,thetotalbondingstrengthofγ/γ′interfacedecreaseswithincreasingδ.Therefore,themagnitudeandsignoflatticemisfitmustbecarefullycontrolledforbalancingthehightemperaturecreepstrengthofNi-basesinglecrystalsuperalloyandthestructuralstabilityofγ/γ′interfacewhenonedesignsanewNi-basesinglecrystalsuperalloy.
简介:由Synechcoccus在Ni的简历累积上影响因素在这篇论文被学习。当到干燥重量集中ofSynechcoccus的Ni的集体比率是16-18%时,简历累积在附近是在水的solution.Bioaccumulation数量的80min的Ni的使平衡时间到达了最大值。Bioaccumulation数量与增加pH增加了。最佳pHwas9-10和更高的pH导致了Ni的降水(哦)_2。Bioaccumulation数量被在35℃到达他们的optima的温度和轻紧张也影响,无生命的水藻的3000Ixrespectively.Bioaccumulation比生活水藻的大。
简介:AseriesofNi-Hrechargeablebatterieswithatrademarkof‘JJJ’weresuecessfullydevelopedbyJiangnanTribleJcorporation,GuangdongProvince,andwereputintobatchproductionthisyear.ResearchonNi-HbatteryisoneoftheimportantprojectsinChina’sNationalHigh-TechProgramm.ScientistsinTribleJCorp.startedtheresearchlastyear.Afternearlyoneyear’sarduouswork,theycom-pletedthelabworkontheprojectandcametothe
简介:Aseriesofsolarradiationtestsforthepolytetrafluoroethylene(PTFE)bulkandfilmsampleswerecarriedoutusingQ-SUNXE-3-HSCtypeSolarRadiationSimulator,withthetestparametersasfollows:radiationintensityis1120W/m~2,temperatureis55℃andhumidityis70%RH.Surfacemorphology,compositionandmicrostructureofthePTFEsamplesbeforeandafterradiationtestswerecharacterizedcontrastively.EffectofsolarradiationonthetribologyandwettingpropertiesofPTFEwerealsostudiedbytribometerandcontactangletester,respectively.Theresultsshowthat,forradiatedPTFE,surfaceroughness,therelativecontentofCelement,thefrictioncoefficientsandthecontactanglewithwaterincreasedinvaryingdegrees.Inconclusion,theobviouschangeinPTFEsamplescanbemainlyattributedtobreakof(CFx)-CbondsafterbombardmentofhighenergyUVphotons,whichcausesthelossofF-richgroups,oxidation,crosslinkingandrestructuringofactiveunsaturatedgroups.