简介：摘要目的研究超声弹性成像在乳腺BIRADS分类的应用价值。方法选取2015年1月-2016年5月本院收治的通过病理确诊176例乳腺肿瘤（210个病灶），分别应用二维常规超声和超声弹性成像进行BIRADS分类，将2类和3类归为良性，4类和5类归为恶性。以病理结果为金标准，比较二者诊断价值。结果二维常规超声和超声弹性成像检查均存在一定误诊或漏诊概率（14.76%和7.62%），且超声弹性成像灵敏度、特异度、准确率、阳性预测值、阴性预测值均高于常规超声，差异在统计学上均有意义（P＜0.05）。结论超声弹性成像可以提高常规二维超声对乳腺肿块BI-RADS分类的准确性和鉴别诊断乳腺良恶性肿瘤。

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简介：UltrasonicvelocitieshavebeenmeasuredinsinglephaseBi1.7Pb0.3Sr2CaCu2O8+xandBi1.7Pb0.3Sr2Ca2O10+xpolycrystallinesamples.Anomalouschangesofbothlongitudinalandtransversevelocitieswereobservednear200K,whichindicatesthatsomestructuralphasetransitiomightoccur.Theelasticconstantsofthesesampleshavebeendeterminedfromthemeasuredultrasonicvelocitydata,whicharemuchsmallerthanthoseofYBa2Cu3O7-yandBaTiO3,manifestingthattheinterlayercoup-lingwilldramaticallydecreasewhenthec-axesoftheunitcellsoftheseperovstite-likemultilayerceramicsincrease.ThevaluesofPoissonratio,however,ofthoseceramicsareveryclose,implyingsimilarinteratomicbondingforces.Correctedtovoid-freestate,theDebyetemperatureofthesematerialsisestirnatedas270±20k.ThetemperaturedependenceofDebyetemperaturesforthesematerialsisalsocalculatedbyusingthesamemethodandreportedforthefirsttime.

简介：　　Enantioimericallypure1,l'-bi-2-naphthol(BINOL)1anditsderivativesareimportantchiralligandsandauxiliariesforanumberofasymmetrictransformations1suchasaldolcondensations,alkylations,Diels-Alderreactions,Michaeladditions,epoxidations,etc.Opticallypure1andtheirderivativeshavealsobeenusedextensivelyinchiralrecognition,chiralseparationandintheconstructionoffunctionalisedmaterials2.Furthermore,(R)-and(S)-BINOLarealsofundamentalstartingmaterialsforthesynthesisofalargevarietyofotherchiralbinaphthylssuchasMOP(2c),NOBIN(2d)andBINAP(2e).Asaresultthedevelopmentofefficientandeconomicmethodsforthepreparationofopticallypure1hasattractedmuchattentioninrecentyears3andnovelmethodsfortheresolutionof(±)-1continuetobedeveloped.……

简介：Multi-nucleontransferreactionplaysanimportantroleinthesynthesisofnewnuclides[1].Inthereactionsof20Ne+209Bi,someshort-livednucleiproducedbytransferring26nucleonswerediscovered.Theexperimentof20Ne+209Biwasperformedatgas-filledrecoilseparatorinLanzhou[2].A400g/cm2thick209Bitargetwasbombardedwith20NebeamdeliveredbyacceleratorHIRFL.

简介：黄磷(Bi1-xSmx)2ZnB2O7(x=0.01，0.03，0.05，0.07，和0.09)被常规稳固的州的反应综合。所有样品的纯净被X光检查粉末衍射(XRD)检查。XRD分析证明所有这些混合物具有Bi2ZnB2O7的一个单个阶段，显示在Bi2ZnB2O7的双性人(3+)能被没有晶体结构的变化的Sm(3+)部分代替。在房间温度的刺激和排放系列显示出Sm(3+)的典型4f-4f转变。主导的刺激线在404nm附近由于(6)H5/2→(4)K11/2和排放光谱在563，599，646，和704nm由一系列线组成由于(4)G5/2→(6)H5/2，(6)H7/2，(6)H9/2，并且(6)H11/2分别地。在Bi2ZnB2O7的Sm(3+)的最佳的集中关于3mol%(相对1mol双性人(3+))并且批评距离Rc作为2.1nm被计算。Bi1.94Sm0.06ZnB2O7的排放紧张的温度依赖在在100和450K之间的温度范围被检验。紧张下降了到起始的紧张的一半的熄灭的温度是280K。为在Bi1.94Sm0.06ZnB2O7的Sm(3+)的一生作为0.29和1.03ms的价值被适合。

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简介：在分析hydrotreating催化的裂开联合处理的传统的残余的劣势以后，RIPP建议了集成与催化裂开对待的残余水疗院的一种双向联合技术叫了不推进的RICP再循环FCC在FCC单位内的重周期油(HCO)并且把HCO送到对待为并发地受到对待的水疗院的残余作为冲淡的油联合起来的残余水疗院在被用作FCC以前喂油。RICP技术能刺激与FCC轻精华的增加的收益一起通过HCO的利用对待反应的残余水疗院，导致提高的石油利用和精炼厂的经济好处。

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简介：摘要 随着大屏硬件技术和多点触控技术的发展，通过大屏多点触控技术的BI管理驾驶舱系统，能够使企业管理者更直观地观察企业各项经济指标数据，为企业管理者决策提供数据支持。因此，本文对基于大屏多点触摸技术的BI管理驾驶舱系统进行了简要的分析。

简介：摘要：为了更好且更快的实现这个目标，同时融入BI大数据信息化管理，经过抽取维修业务数据并且转变分析，按照统计生产的指标数据调整维修计划，降低外委维修投入，降低生产成本，有效提升经济效益。本文主要讨论BI数据分析系统、BI数据分析和大数据的区别、BI数据分析在油田设备自檢自修中的应用。

简介：采用丝印法在铝基板上制备具有低室温电阻率、适中热敏常数的负温度系数BaCo0.02ⅡCo0.04ⅢBi0.94O3/Ba0.5Bi0.5Fe0.9Sn0.1O3复合热敏厚膜。采用数字多用表、吉时利2400和阻抗分析仪对热敏厚膜的电学性能进行表征。结果表明：随着Ba0.5Bi0.5Fe0.9Sn0.1O3含量从0.05增加至0.25,厚膜的室温电阻率、热敏常数和峰值电压均有所增加且分别处于1.47-26.5Ω·cm、678-1345K和18.9-47.0V范围内,厚膜峰值电压对应的电流也有所降低且处于40-240mA范围。阻抗谱测试表明,这些热敏厚膜表现出非正常的异质电学微结构行为,由高阻态的晶粒和较低电阻态的晶界区域构成。由此可知,在BaCo0.02ⅡCo0.04ⅢBi0.94O3中添加Ba0.5Bi0.5Fe0.9Sn0.1O3改善了热敏行为但也恶化了电流特征.

简介：Recently,bismuthsulfide(Bi2S3)hasattractedmuchattentioninthethermoelectriccommunityowingtoitsabundance,lowcost,andadvancedproperties.However,itspoorelectricaltransportpropertieshavepreventedBi2S3devicesfromrealizinghighthermoelectricperformance.Inthiswork,ourmotivationistodecreasethelargeelectricalresistivity,whichisrecognizedastheoriginofthelowZTvalueinundopedBi2S3.Wecombinedmeltingandsparkplasmasintering(SPS)inacontinuousfabricationprocesstoproduceBi2S3–xSex(x=0,0.09,0.15,0.21)andBi2S2.85–ySe0.15Cly(y=0.0015,0.0045,0.0075,0.015,0.03)samples.OurresultsshowthatSealloyingatSsitescannarrowthebandgapandactivateintrinsicelectronconduction,leadingtoahighpowerfactorof~2.0μW·cm–1·K–2atroomtemperatureinBi2S2.85S0.15,about100timeshigherthanthatofundopedBi2S3.Moreover,ourfurtherintroductionofClatomsintotheSsitesresultedinasecond-stageoptimizationofcarrierconcentrationandsimultaneouslyreducedthelatticethermalconductivity,whichcontributedtoahighZTvalueof~0.6at723KforBi2S2.835Se0.15Cl0.015.OurresultsindicatethathighthermoelectricperformancecouldberealizedinBi2S3withearth-abundantandlow-costelements.

简介：摘要目的探讨超声乳腺影像报告与数据系统(Breast Imaging Reporting and Data System，BI-RADS)分类在特殊类型乳腺癌中的诊断价值。方法回顾性分析2009年8月至2020年8月于浙江大学医学院附属第二医院诊治并经手术病理证实的特殊类型乳腺癌患者112例(112个病灶)，患者均行术前超声检查。分别由高年资主治医师及低年资住院医师依据超声BI-RADS分类对乳腺病灶进行评估。以组织病理学为金标准，分析BI-RADS分类诊断特殊类型乳腺癌的敏感性及准确性，比较不同特殊类型乳腺癌的BI-RADS分类及超声恶性征象之间的差异。对两名医师的评估结果进行Kappa检验，判断一致性是否良好。结果112例患者中，化生性癌20例，伴有髓样特征的浸润性癌19例，大汗腺分化的癌16例，黏液癌12例，浸润性微乳头状癌12例，浸润性乳头状癌10例，浸润性小叶癌6例，其他特殊类型癌17例；BI-RADS 3类4例(3.5%)，BI-RADS 4a类13例(11.6%)，BI-RADS 4b类42例(37.5%)，BI-RADS 4c类47例(42.0%)，BI-RADS 5类6例(5.4%)。BI-RADS分类诊断特殊类型乳腺癌的敏感性为96.43%，准确性为96.43%。不同特殊类型乳腺癌的BI-RADS分类差异有统计学意义(P<0.05)。特殊类型乳腺癌病灶常表现为低回声、不规则形、边界成角或微分叶。不同特殊类型乳腺癌病灶的最大径、边界、内部回声及后方回声差异有统计学意义(均P<0.05)。两名医师诊断结果一致性良好，Kappa值为0.789。结论不同特殊类型乳腺癌超声征象有差异，超声BI-RADS分类对特殊类型乳腺癌诊断准确性较高。

简介：Thermoelectric(TE)materialsareakindoffunctionalmaterialswhichcanbeusedtoconvertdirectlyheatenergytoelectricityorreversely.Thethermoelectriceffectsholdgreatpotentialforapplicationinpowergenerationandrefrigeration.Bi2Te3anditsalloysarewellknownasbestTEmaterialscurrentlyavailablenearroomtemperature.Thispaperstudiesrespectivelytheeffectsofsparkplasmasintering(SPS)onelectricperformanceofBi0.5Sb1.5Te3thermoelectricmaterialsthatarepreparedthroughvacuummeltingandballmilling.ThroughX-rayDiffractionandcoldfieldemissionscanningelectricmicroscopes4800,thephaseconstituentandmicrostructureoftheTEmaterialssampleswereanalyzed.ElectricconductivityandpowerfactorcanbeimprovedwiththeriseofSparkPlasmaSinteringtemperature(from300to500℃)andpressure(from30to60MPa),andthedensityandmechanicalstrengthofBi0.5Sb1.5Te3thermoelectricmaterialincrease,too.

简介：Carbazole-basedbi-functionalphotorefractivepolyacrylateswerepreparedviafreeradicalpolymerizationandpost-azo-couplingreaction.ThestructureofpolymerswascharacterizedbyFouriertransforminfraredspectroscopy(FTIR)andprotonnuclearmagneticresonance(1H-NMR)spectroscopy.Thedifferentialscanningcalorimetry(DSC)andthethermalgravimetricanalysis(TGA)wereusedtocharacterizethethermalpropertyofpolymers.Theresultsindicatethatthoughtheglasstransitiontemperature(Tg)ofpolymersincreaseswithincreasingtheratioofNLOgroups,thepolymerswithdifferentratiosofNLOgroupsstillallshowlowglasstransitiontemperaturesaround60°C,andgoodthermalstability,whicharefavorabletothepracticalapplicationofthesepolymers.Thegelpermeationchromatographic(GPC)resultindicatesthatthesepolymersallhavehigh-molecular-weightwhichisfavorabletothelongtermstabilityofthematerial.Further,thesepolymershavegoodsolubilityinchloroformsolvent,andthesolutionscaneasilybefabricatedintoopticallytransparentfilms.Gaincoefficientsof75cm-1,185cm-1and66cm-1canbeobservedatzeroexternalelectricfieldwithoutanyadditionagentorpre-polingforpolymersP-2,P-3andP-4respectively.ThedifferentcontentsofNLOgroupsresultinthedifferentpropertiesofpolymersP-2,P-3andP-4.

简介：TheelectronicpropertiesandtopologicalphasesofThXY(X=Pb,Au,Pt,PdandY=Sb,Bi,Sn)compoundsinthepresenceofspin–orbitcoupling,usingdensityfunctionaltheoryareinvestigated.TheThPtSncompoundisstableintheferromagneticphaseandtheotherThXYcompoundsarestableinnonmagneticphases.Bandstructuresofthesecompoundsintopologicalphases(insulatorormetal)andnormalphaseswithingeneralizedgradientapproximation(GGA)andEngel–Voskogeneralizedgradientapproximation(GGAEV)arecompared.TheThPtSn,ThPtBi,ThPtSb,ThPdBi,andThAuBicompoundshavetopologicalphasesandtheotherThXYcompoundshavenormalphases.Bandinversionstrengthsandtopologicalphasesofthesecompoundsatdifferentpressurearestudied.Itisseenthatthebandinversionstrengthsofthesecompoundsaresensitivetopressureandforeachcompoundasecond-orderpolynomialfittedonthebandinversionstrengths–pressurecurves.

简介：摘要电子封装产业的无铅化是国民经济发展的重要方向，本文根据近年来无铅焊料的新发展趋势，着重叙述了Sn-Bi系无铅焊料的研究进展，阐述了Sn-Bi系无铅焊料的优缺点，以及合金化对其性能的改良情况。最后展望了无铅焊料的发展趋势和新的发展思路。