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简介:TheballmillingofFe-24MnandFe-24Mn-6Simixedpowdershasbeenperformedbythehighenergyballmillingtechnique.ByemployingX-raydiffractionandMoessbauermeasurements.Theccmpositionevolutionduringthemillingprocesshasbeeninvestigated.TheresultsindicatetheformationofparamagneticFe-MnorFe-Mn-Sialloyswithametastablefccphaseasfinalproducts.whichimplythattheFeandMnproceedaco-diffusionmeenanismthroughthesurfaceoffragmentedpowders.Thethermalstabilityandcompositionevolutionoftheas-milledalloyswerediscussedcomparingwiththebulkalloy,.
简介:Wehavestudiedtheelectronic,bondingandenergeticcharacteristicsoftheFe-Sibinarysystemusingthetight-bondingextendedHuckelmethod.AmongtheFe-Sibinarycompounds,FeSihasthemostsymmetricgeometricarrangementinthecrystalstructure.Italsopossessesthelargestcohesiveenergyperatom.ThiscorrelatestothefactthatFeSiisthemoststablecongruently-meltingcompoundinthebulkphasediagram.Anestimateofinteractionenergiesbetweendifferentatomsisalsogiven.
简介:为研制具有较宽频带微波吸收性能的材料,采用机械合金化法制备CoxFe80-xSi20(x=0,6,10,14摩尔百分数)合金粉体,使用SEM、XRD和矢量网络分析仪等测试手段,研究了合金粉体微观结构及Co-Fe-Si合金微波吸收性能。结果表明:制备的合金粉末呈片状,主要由-Fe相组成;Co的添加使Co-Fe-Si合金出现两个微波吸收峰。在较高频段处的微波吸收峰值随Co的添加先增大后减小。在涂层厚度为1.8mm时,x=10的合金低频处的反射率最小值最小,合金吸波峰频率和峰值分别为6.2GHz和-14.8dB,合金在高频处吸波峰频率和峰值分别为18GHz和-8.8GHz,合金反射率低于-5dB的带宽达14GHz,具有良好的微波吸收宽频效应。
简介:Moleculardynamics(MD)simulationswereperformedtostretchtherectangulargraphenesheetsdopedwithsilicon,nitrogenorboronatoms.Young’smodulus,ultimatestress(strain)andenergyabsorptionweremeasuredforthegraphenesheetswiththedopingconcentration(DC)rangingfrom0to5%.Theemphasiswasplacedonthedistincteffectsofeachindividualdopantonthefundamentalmechanicalpropertiesofgraphene.TheresultsindicatedthatincorporatingthedopantsintographeneledtoanalmostlineardecreaseinYoung’smodulus.Monotonicreductionsinultimatestrength,ultimatestrainandenergyabsorptionwerealsoobserved.Suchdopingeffectswerefoundtobemostsignificantforsilicon,lesspronouncedforboron,andsmallornegligiblefornitrogen.Theoutputsprovideanimportantguidanceforthedevelopmentandoptimizationofnovelnanoscaledevices,andfacilitatethedevelopmentofgraphene-basedM/NEMS.
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简介:ToevaluatethepossibilityofusingGd-Si-Gealloysinmagneticrefrigerators,samplesofGd-Si-GealloysweremadeofdomesticGd.Themagnetocaloriceffectofsampleswasestimatedbymagneticentropychange(-ΔSm)calculatedfromM-HcurvesaccordingtoMaxwellrelation.ThefirstorderphasetransformationwasdestroyedduetotheimpuritiesinthecommercialGd,sothatnogiantmagnetocaloriceffectwasfound.ThesamplesmadeofpurifiedGdexhibitfirstorderphasetransformation,andthe-ΔSmisbasicallyconsistentwiththepublisheddataofAmeslaboratory,USA.ThisworkprovesthatGd-Si-GealloysmadeofdomesticGdcanbeutilizedinmagneticrefrigerators.
简介:摘要目的分析脑梗塞的临床治疗方法与效果。方法将本中心收治的150例脑梗塞患者作为本次的研究对象,并随机分为观察组和对照组。观察组采用中西医结合的治疗方法,对照组采取单纯的西医治疗。观察两组患者的临床疗效。结果观察组患者共有68例患者治疗有效,治疗有效率为90.67%。对照组共有33例患者的治疗为有效,治疗总有效率为44%。两组患者治疗的有效率相比较,差异显著,P<0.05。结论中西医结合治疗脑梗塞效果明显优于单纯的西医治疗。不仅能够实现标本兼治的目标,还能达到较高的治愈率,值得临床的推广实践。
简介:摘要妇人“症瘕”,相似于现代妇科一系列急慢性炎症,西医以消炎治疗为主,且有反复发作现象,笔者用古方“桃仁四物汤”加减治疗该类病症150人,皆取得较好疗效。
简介:摘要目的探讨甲状腺功能亢进症引起的肝损害的发生率、相关因素及临床表现。方法回顾性分析150例甲亢性肝损害及同期140例单纯性甲亢肝功能正常的临床资料。结果290例甲亢患者中发生肝损害150例,甲亢导致肝损害的发生率高达51.29%。甲亢患者年龄与甲亢性肝损害的发生率有关,即年龄越大甲亢性肝损害发生率就越大,在年龄大于65岁患者中甲亢性肝损害发生率为86.34%。甲亢患者的性别与甲亢性肝损害的发生率无关。甲亢患者的病程与甲亢性肝损害的发生率有关,病程大于12个月的甲亢性肝损害发生率最高,为79.7%,病程越长甲亢性肝损害发生率越高。结论甲亢性肝损害的发病率较高,病情的严重程度与患者年龄、病程长短有密切关系。医生应该提高对甲亢性肝损害的认识并且及时诊断,加强对原发病的治疗,选用合理的治疗方案,减少并且预防甲亢性肝损害的发生。
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