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简介：Directconversionoffructose-basedcarbohydratesto5-ethoxymethylfurfural(EMF)catalyzedbyLewisacidinethanolwasinvestigated.ItwasfoundthatBF3(Et)2Owasfavorablefor5-hydroxymethylfurfural(HMF)etherificationtoEMF.BF3(Et)2OcombinationwithAlCl36H2Owiththemolarratioof1wasaneffectivecatalystsystemforsynthesisofEMFfromfructose-basedcarbohydrates.55.0%,45.4%and23.9%ofEMFyieldswereobtainedfromfructose,inulinandsucroseunderoptimizedconditions,respectively.

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简介：HighlytexturedHeusleralloyMn46Ni42Sn11Sb1ribbonswerepreparedbymeltspinning.TheannealedhighMncontentMn46Ni42Sn11Sb1ribboncross-sectionmicrostructure,crystalstructure,martensitictransformation（MT）,andmagnetoresistance（MR）propertieswereinvestigated.TheMRintheannealedribbonwasassessedbythemagneticfielddirectionperpendiculartotheribbonsurfacewiththemagneticfieldupto30kOe.Thelargenegativevalueof25%forMRwasobtainedat244K.Theexchangebias（EB）effectsoftheas-spunandannealedribbonswereinvestigated.Afterannealing,theEBeffectshavebeenimprovedbyabout25Oeatthetemperatureof50K.Themagnetizationshaveincreasedapproximatelyby10%morethantheas-spunribbon.

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简介：我们在Mn50Ni40SnSbx(x=1，2，3，和4)合金。所有准备样品在房间温度与空间组一起展出B2类型结构。Sb的替换增加原子价电子集中并且减少联合起来的房间体积。作为结果，当x增加，magnetostructural转变向更高的温度很快变。在在不同磁场变化下面的磁性的熵的变化在这转变附近被探索。等温的磁化曲线展出典型metamagnetic行为，显示magnetostructural转变能被一个磁场导致。悦耳的martensitic转变和磁性的熵变化建议那Mn50Ni40SnSbx合金是应用在的吸引人的候选人固态制冷。

简介：本文展示了作者基于实用性、探究性、趣味性、情感性的《牛顿第二定律》课堂教学的实例，提出了物理课堂教学要结合校情、生情对教材进行二次开发，要讲究实效，让学生能力在学习中得到提高，让情感在课堂中自然渗透。

简介：Basedonthecovariantprolongationstructuretechnique,weconstructtheintegrablehigher-orderdeformationsofthe(2+1)-dimensionalHeisenbergferromagnetmodelandobtaintheirsu(2)×R(λ)prolongationstructures.ByassociatingthesedeformedmultidimensionalHeisenbergferromagnetmodelswiththemovingspacecurveinEuclideanspaceandusingtheHasimotofunction,wederivetheirgeometricalequivalentcounterparts,i.e.,higher-order(2+1)-dimensionalnonlinearSchrdingerequations.

简介：首次在温和条件下，用在传统微孔沸石合成中常作为导向剂的乙二胺或1，6-己二胺替代NaOH作催化剂合成出SiO2基中孔MCM-41分子筛。合成样品用XRD和N2吸附等温线进行表征。实验结果表明，由于这种替代，使相应合成样品及焙烧样品的中孔骨架结构的有序度明显提高。在XRD图中四个衍射峰清晰可辨，是典型的六方紧密堆积，晶胞参数a0分别为4.11nm和3.75nm，且d100值随所用胺分子中碳链的增长逐渐从3．56nm减少到3．24nm，同时产物孔径由中孔转变为微孔。更多还原

简介：WereportQ-switchedandmode-lockederbium-dopedall-fiberlasersusingternaryReS2(1-x)Se2xassaturableabsorbers(SAs).ThemodulationdepthandsaturableintensityofthefilmSAare1.8%and0.046MW∕cm2.InQ-switchedmechanismoutput,thepulsewascenteredat1531.1nmwithmaximumpulseenergyandminimumpulsewidthof28.29nJand1.07μs,respectively.Inmode-lockedoperation,thepulsewascenteredat1561.15nmwithpulsewidthof888fs,repetitionrateof2.95MHz,andmaximumpulseenergyof0.275nJ.Tothebestofourknowledge,thisisthefirstreportonthemode-lockedEr3+-dopedfiberlaserusingternarytransitionmetaldichalcogenides.Thisworksuggestsprospective2D-materialSAscanbewidelyusedinversatilefieldsduetotheirattractiveoptoelectronicandtunableenergybandgapproperties.

简介：Thereisagrowingsupportforthelowlyingscalarmesonsf0(500),f0(980),a0(980),and(800)tobegenerateddynamicallyfromtheinteractionofpseudoscalarmesons,whilethecaseofthenextsetofscalarresonancesathigherenergies,f0(1370),f0(1710),K0(1430)ismoreaquestionofdebate.Soisthecaseofthetensorresonancesf2(1270),f′2(1525),K2(1430).AnewperspectiveonthesestateshasbeenofferedinRef.[1]wherethef0(1370)andf2(1270)resonancesareshowntobegeneratedfromtheinteractionprovidedbythelocalhiddengaugeLagrangiansimplementingunitarization.Itisshownthattheideaofthenatureofthesestatesasvectormeson-vectormesoncompositestateshasbeentestedinmanyreactions.Yet,thepermanentdiscussionoftheissuedemandsextrachecksforotherobservablesand,inthissense,theweakdecaysbringanewsourceofvaluableinformationthatshouldservetotestdifferentmodels.