简介：研究Sb元素含量对Sn-Bi系焊料性能的影响。通过差示扫描量热法研究Sn-Bi-Sb焊料的熔化行为。采用铺展实验研究焊料在Cu基板上的润湿性。测试Sn-Bi-Sb/Cu结合界面的力学性能。结果表明：三元合金中含有包共晶反应形成的共晶组织，随着Sb含量的增加，共晶组织增多；在加热速率为5℃/min的条件下，三元合金显示出更高的熔点和更宽的熔程；添加少量Sb对Sb-Bi系焊料的铺展率有影响；在焊料铺展过程中形成反应过渡层，反应过渡层中存在Sb元素而无Bi元素，过渡层厚度随着Sb元素含量的增加而增大。Sn-Bi-Sb焊料的剪切强度随着Sb元素含量的增加而升高。

简介：随着社会不断进步，群众对健康的观念也从治疗疾病到预防疾病转变。当然检查手段和检查设备的更新和普及也为疾病的早期发现做出了不小的贡献。近年来，很多女性朋友在体检时发现“乳腺结节”的情况越来越多，很多人对“乳腺结节”不了解，认识不足，担心自己患上了“乳腺肿瘤”，焦急万分，甚至影响到了自己的工作和生活。到底乳腺结节是啥？出现了乳腺结节该怎么办呢？

简介：Todevelopuniformandseismicenvironment-dependentdesignspectrum,commonaccelerationresponsespectralcharacteristicsneedtobeidentified.Inthispaper,abi-normalizedresponsespectrum(BNRS)isproposed,whichisdefinedasaspectrumofpeakresponseaccelerationnormalizedwithrespecttopeakaccelerationoftheexcitationplottedvs.thenaturalperiodofthesystemnormalizedwithrespecttothespectrumpredominantperiod,Tp.Basedonastatisticalanalysisofrecordsfromthe1999Chi-Chiearthquake,theconventionallynormalizedresponsespectrum(NRS)andtheBNRSareexaminedtoaccountfortheeffectsofsoilconditions,epicentraldistance,hangingwallanddamping.ItisfoundthatcomparedtotheNRS,theBNRSismuchlessdependentonthesefactors.Finally,somesimplerelationshipsbetweentheBNRStoraspecifieddampingratioandthatforadampingratioof5%,andbetweenthespectrapredominantperiodandepicentraldistancefordifferentsoiltypesareprovided.

简介：摘要：采用调整BI废液与硝酸配比与添加消泡剂的方法有效地控制了氧化工序反应程度，并结合适当的工艺调整和改造解决了氧化工序因反应过快而发生的喷料。

简介：

简介：

简介：摘要目的构建简便可用的225Ac-213Bi发生器，为研发靶向α治疗药物提供短半衰期α核素213Bi。方法以DIPEX树脂作为发生器固定相，采用Sep-Pak Alumina N Plus Light Cartridge小柱作为柱体构建发生器，以盐酸作为淋洗液。使用γ能谱对淋洗所得的213Bi进行纯度分析，验证使用活度计对225Ac与213Bi活度进行测量的方法。研究不同浓度盐酸溶液及不同保存状态下发生器的洗脱曲线，确定最佳使用方案。结果使用商品化225Ac、100 mg DIPEX树脂和Sep-Pak Alumina N Plus Light Cartridge小柱构建柱体积为0.35 ml的225Ac-213Bi发生器，通过注射盐酸淋洗获得213Bi；获得213Bi的γ能谱纯净，测定半衰期为(45.75±0.12) min，与理论值(45.6 min)一致。CRC®活度计刻度号#086和#018可用于测量225Ac和213Bi活度，平均测量误差分别为-2.6%和+0.2%。225Ac-213Bi发生器使用2 mol/L盐酸作为淋洗液，320 μl淋洗体积可获得90%洗脱率；发生器应在淋洗溶液中保存，避免干燥。结论构建的225Ac-213Bi发生器可制备213Bi用于靶向α治疗。

简介：

简介：Asoneofcandidatesforthefuelcladdingorstructurematerialusedinfourthgenerationfissionandfusiondemonstratereactor,MAXphasehasthepropertiesofbothceramicandmetal,suchashighmeltingpoint,hightemperaturestability,gooderosionresistanceandradiation-damagetolerance[1;2].Maxphaseisaseriesofceramicsofnanolamellarandhexagonalstructure.Mrepresentstransitionelement.Arepresentsthethirdorfourthmaingroupelement.XrepresentNandC.Inthedesignoflead-cooledfastreactor,itisrequiredthatthematerialshouldendurethecorrosionofliquidPb-Bialloy.Therefore,understandingoftheoxidelayersandtheirgrowthmechanismsinLBEisfundamentallyimportantforthedevelopmentofcandidatematerials.

简介：Anewtwo-dimensionalstructuremodulationalongc-andb-axeshasbeendiscoveredinsuperconductingsinglecrystalsofBi2.13Sr1.87CuO6+δ(Bi2201)byx-rayscattering.Suchmodulationstructuredoesnotexistinnon-superconductingBi2201singlecrystals.Butinsteadlatticedistortionsareobservedinthea-b-plane.Thisphenomenonmayindicatethatbothstrainrelaxationandchargemodulationinthea-b-planeareimportanttotheoccurrenceofsuperconductivityinthecopperoxides.

简介：Inthispaper,thestresssingularityanalysisatthecracktiponelasticbi-materialinter-facesisconsidered.ThegoverningequationsofplaneelasticityinsectorialdomainarederivedtobeinHamiltonianformviavariablesubstitutionandvariationalprinciple.Themethodsofseparationofvariablesandconjugatesymplecticeigen-functionexpansionaredevelopedtosolvetheequationsinsectorialdomain.Thegeneralformulaeforthesolutionofstresssingularitiesatthecracktiponbi-ma-terialinterfacesareputforward,andanewsolutiontechniqueforfractureproblemsispresented.

简介：Thispaperproposesasimplegeometricalraybasedapproachtosolvethestereocorrespondenceproblemforthesingle-lensbi-prismstereovisionsystem.Eachimagecapturedusingthissystemcanbedividedintotwosub-imagesontheleftandrightandthesesub-imagesaregeneratedbytwovirtualcameraswhichareproducedbythebi-prism.Thisstereovisionsystemisequivalenttotheconventionaltwocamerasystemandthetwosub-imagescapturedhavedisparitieswhichcanbeusedtoreconstructbackthe3-dimensional(3D)scene.ThestereocorrespondenceproblemofthissystemwillbesolvedgeometricallybyapplyingtheepipolargeometryconstraintonthegeneratedvirtualcamerasinsteadoftherealCCDcamera.Experimentsareconductedtovalidatetheproposedmethodandtheresultsarecomparedtothecalibrationbasedapproachtoconfirmitsaccuracyandeffectiveness.

简介：研究了FeMn／Co多层膜界面插入Bi前后微结构的变化。利用磁控溅射法制备了FeMn/Co多层膜，利用X射线小角反射和漫散射技术进行了表征，得到结果如下：插入Bi之前，在FeMn/Co界面处确实存在FeMnCo的成分混合存在，插入Bi之后，FeMnCo的成分中掺入了Bi。而且，在FeMn/Co界面处Fe，Mn，和Co的元素分布不相同。

简介：Abi-caponbeamforming(BCB)algorithmformulti-inputmulti-output(MIMO)radarisdevelopedonthebasisofcorrelationdomain.Byvectorizingtheechomatrixanditstranspose,theconventionalcaponcostfunctionistransformedintobi-caponquadraticfunctions.Bycalculatingtwolowerdimensionalweightvectorswithsub-matricesofthecorrelationmatrix,BCBcansignificantlydecreasethecomputationalcomplexityandtherequirementoftrainingsamples.Inthepresenceofshortdatarecords,BCBcanachievebetterinterferencesuppressionperformancethanfullyadaptivecaponalgorithm.Simulationresultsarepresentedtodemonstratetheeffectivenessoftheproposedmethod.

简介：Inthiswork,Bi2Te3films(250nm)arefabricatedonSiO2/Sisubstratesbyradiofrequency(RF)magnetronsputteringatroomtemperature,andthepreparedfilmsareannealedoverthetemperaturerangeof200°Cto400°C.Crystallinityandelectricalpropertiesofthefilmscanbetunedcorrespondingly.ThepowerfactorsofBi2Te3filmsof0.85μW/K2cmto11.43μW/K2cmwereachievedafterannealing.Theinfraredreflectancemeasurementsfrom2.5μmto5.0μmdemonstratethatthereisalsoaslightred-shiftoftheplasmaoscillationfrequencyintheBi2Te3films.Bymeansofplasmoniccalculations,weattributethered-shiftofabsorptionpeakstothereductionofcarrierconcentrationandthechangeofeffectivemassofBi2Te3filmswiththeincreasedannealingtemperature.

简介：发展无铅焊接在包装工业的电子学作为关键问题之一出现了。Bi-Sn-Ag最容易溶解的合金被看作了之一无铅焊接能代替有毒的Pb-Sn的材料最容易溶解没有增加焊接温度，焊接。我们调查了温度的效果Bi-Sn-Ag的机械、电、热的性质上的坡度和生长率第三的最容易溶解的合金。Bi-47wt%Sn-0.68wt%Ag合金方向性地在一个常数与不同温度坡度(G=2.33-5.66K/mm)向上被团结生长率(V=13.25m/s)并且与不同生长在一个常数的率(V=6.55-132.83m/s)在生长的温度坡度(G=2.33K/mm)仪器。微观结构()，microhardness(HV)，张力的应力()，电的抵抗力()，并且热性质(H，Cp,Tm)在方向性地团结的样品上被测量。相关性，HV，，并且在G和V上被调查。根据试验性的结果，价值与增加G和V减少，但是HV，，并且价值与增加G和V增加。电的抵抗力的变化()因为在范围与温度扔样品300-400K也被测量由用标准dc四点的探查技术。熔化的热含量(H)和特定的热(C为一样的合金的p)借助于微分扫描也是坚定的从从最容易溶解的液体在转变期间加热踪迹到最容易溶解的固体的热量计(DSC)。

简介：TherecyclablePEG-boundbi-cinchonaalkaloidligandhasbeensuccessfullyappliedtothehomogeneouscatalyticasymmetricdihydroxylationofvariousalkenes;goodyieldsandexcellentenantioselectivitieswereobtained,Theligandcouldbeeasilyrecoveredandreusedfor10timeswithoutanyapparentlossofitscatalystefficiency.

简介：Wesynthesized(Pb,Cd)Sr2(Y,Ca)Cu2O7+x,phasesuperconductor.AftersubstitutionofPbwithBi,theBiCd1212phaseshowsnosuperconductivity.AlthoughpreviousEXAFSstudyhasshownthelocalstructureenvironmentoftheCuissimilarinbothcompounds,EXAFSresultsofBiandPbheredemonstratethatσ2ofPb-Oin-planeislargerthanthatofBi-Oinplane,whereasσ^2ofPb-OapicalissmallerthanthatofBi-O,wheraseσ^2ofPb-OapicalissmallerthanthatofBi-Oapical.TheSrshellfeaturesarealsodiffernet,itappearedthatsuperconductivityneedssomedisorder.incarrierreservoirlayer,whichisduetothesubstitutionaldefectcausedbydifferentionicradii.

简介：Inthispaperwedeveloptwoconformingfiniteelementmethodsforafourthorderbi-waveequationarisingasasimplifiedGinzburg-Landau-typemodelford-wavesuperconductorsinabsenceofappliedmagneticfield.UnlikethebiharmonicoperatorA2,thebi-waveoperator□~2isnotanellipticoperator,sotheenergyspaceforthebi-waveequationismuchlargerthantheenergyspaceforthebiharmonicequation.Thisthenmakesitpossibletoconstructloworderconformingfiniteelementsforthebi-waveequation.However,theexistenceandconstructionofsuchfiniteelementsstronglydependsonthemesh.Inthepaper,wefirstcharacterizemeshconditionswhichallowandnotallowconstructionofloworderconformingfiniteelementsforapproximatingthebi-waveequation.Wethenconstructacubicandaquarticconformingfiniteelement.Itisprovedthatbothelementshavethedesiredapproximationproperties,andgiveoptimalordererrorestimatesintheenergynorm,suboptimal(andoptimalinsomecases)ordererrorestimatesintheH~1andL~2norm.Finally,numericalexperimentsarepresentedtoguagetheefficiencyoftheproposedfiniteelementmethodsandtovalidatethetheoreticalerrorbounds.

简介：