简介：PositronannihilationbehaviorshavebeenstudiedinthesinglephaseNd2Fe14BmagnetandthenanocompositeNd2Fe14B/α-Femagnet,preparedbymeltspinning.Theresultsshowedthatthenumberofvacancy-clusteratgrainboundariesincreaseswithincreasingannealingtemperatureforthebothtypesofmagnets.Theincreaseofthiskindofdefectcanimprovethecoercivityof

简介：Ionbeamenhanceddeposition(IBED)wasemployedtoincreasethefrettingfatigueresistanceofTi6AI4V.CrNandTiNhardcoatingswereappliedonthebasematerialandshotpeeningwascombinedwiththehardcoatingstostudytheduplexeffectonfrettingfatigueresistance,TheIBEDcoatingsexhibitedagoodbondingstrength.Theydidnotspalloffevenaftershotpeening.However,anoptimumcompositionofCrNshowedbetterfrettingfatigueresistancethanthatofTiNwiththesameprocessingparameters.

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简介：采用MEMS工艺制备平面微盘腔，再通过二氧化碳激光熔融其表面形成为环状结构，通过三维形貌微系统分析仪、原子力显微镜分别测试了其外部尺寸和表面粗糙度，实验结果表明，锥形光纤近场耦合测得微腔品质因素为4．8×10^5，耦合效率在95％以上，因此激光回流微的方式在得到了新的结构的同时保证了光腔的性能。

简介：FenanowirearraywithstrongshapeanisotropywasemployedasthesoftphaseinNd-Fe-Bbasednanocomposites.TheeffectsoftheFenanowiredistributiononmagneticpropertiesofthenanocompositeswereinvestigatedbymicromagneticsimulation.TheresultsindicatethattheshapeanisotropyofFewiresaddedinthesamedirectionastheuniaxialmagnetocrystallineanisotropyofthehardphasecannotincreasethecoercivityofthenanocomposite.Whenthenanowiresaredistributedperpendiculartotheeasyaxisofthehardphase,theshapeanisotropyofsoftphasecanretardthemomentsfromrotatingtothefullreverseddirection,leadingtoenhancedcoercivity.Inaddition,withincreasingthenanowirediameter,thecoercivityofthenanocompositedecreases,butthedipolarinteractionshowsdifferentrolesinmagneticreversalofnanocompositefordifferentdistributionsofnanowires.ThecurrentresultssuggestthatthecoercivityoftheNd2Fe14B/α-Fenanocompositecanbeenhancedbyintroducingthesoftmagneticnanowirearraywiththediameterlessthantheexchangelengthandwiththelongaxisalongthedirectionotherthantheeasyaxisofhardphase.

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简介：德国Ⅵ系统公司宣布研制出第一个通过多模光纤数据传输速率达40吉比特／s（40Gbit／s）的单VCSEL（垂直腔面发射激光器）。2009年1月份在美国加州SanJose召开的光子学会议上，该公司刚介绍了其20吉比特／s的器件，目前又使它的量子点激光器的调制速率提高了1倍。该公司利用其VCSEL和PIN光探测组件实现了通过多模光纤的40吉比特／s连续传输，这是850hm（波长）光发射的刨记录器件，是用与20吉比特／sVCSEL相同的光刻掩模研制的，但对外延结构作了改进。这种器件设计利用GaAs量子阱中的InAs量子点，并嵌入到AlGaAs基体中。

简介：Three-dimensional-printed(3D-P)titaniumimplantsdisplaymanyadvantages,suchasdesignflexibility,higherefficiency,thecapabilitytoeasilyconstructcomplexorcustomizedstructures,etc.,andisbelievedtopotentiallyreplacetraditionalimplants.However,thebiologicalperformanceofthe3D-Ptitaniumsurfacehasnotbeeninvestigatedsystematically.Herein,weanalyzedthesurfacecharacteristicsof3D-PTi6AI4Vimplantsandevaluatedthebiologicalresponsesofbonemarrowderivedmesenchymalstromalcells(BMSCs)tothe3D-Psurfaceinvitro.Moreover,afterimplantationintotheratfemoralcondylefor3and6weeks,theosseointegrationperformaneewasevaluated.Theresultsshowedthe3D-PTi6Al4Vimplantpresenteddistinctfluctuantmacroscaleroughsurfaceandrelativelybetterhydrophilicitywhichenhancedtheadhesion,proliferation,osteogenicdifferentiationandangiogeneticfactorexpressionofBMSCs.Moreover,theinvivoosseointegrationperformancewasalsobetterthanthatofthecontrolgroupattheearlystage.Thepresentstudysuggestedthe3D-Ptitaniumalloyisapromisingcandidatetobeusedasimplantmaterial.

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简介：以平面环形微腔结构为核心器件，基于量子力学的隧道效应和“参量振荡不稳定”效应，结合理论计算及ANSYS和Beamprop仿真，设计出基于环形微腔结构的超高灵敏度位移传感器，特别是在1．55μm的谐振波下，对所设计的位移传感器进行了ANSYS力学仿真、Beamprop传输特性仿真以及输出特性数值模拟，论证了位移传感器的可行性，并为以后的实验奠定了基础。