简介：FollowingtheChinesemarketopeningtotheworld,manyinternationalfamousbrandproductshaveenteredit,creatingagravechallengetoChineseenterprises.Nowtheyhaveresolvedtocreatefamousbrandproductstocompeteontheinternationalmarket.SofamousbrandproductsarenowbeingcreatedinBeijing.Sincethereformandopenpolicy

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简介：PowersalesofBeijingPowerSupplyBureaureached31.81TWhin2000,itwasincreasedby3.563TWhoverpreviousyear,oragrowthrateof12.61%.Itwastheyearofhighestgrowthsince1978.Accordingtoanalysis,thehighgrowthrateofelectricityconsumptionisattributablemainlytonaturaldeman

简介：NanshuTownisafamousgraphitetownofLaixiCity.NanshuTownhas46graphiteenterpriseswithscattereddistribution,incompleteindustrychain,lowoutput,andlowvalue-added.Inordertoexerttheresourcesadvantage.NanshuTownhasplanedandbuilt

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简介：Fromamathematicalmodelofonekindcomplicatedfinancialsystem,correspondinglocaltopologicalstructuresofsuchkindsystemonconditionofcertainparametercombination,unstableequilibriumpointofthesystem,conditionsonwhichHopfbifurcationiscreatedandstabilityofthelimitcirclecorrespondingtotheHopfbifurcationaswellasconditiononwhichthelimitcircleisstablehavebeenstudied.FromrelationshipbetweeneachparameterandtheHopfbifurcationallthewaytoroutewhichleadstochaosetchavebeenstudied.Followingtheabove,conditionsonwhichcomplicatedbehaviorscreatedlocallyinsuchkindsystemhasbeenanalyzed.Byapplyingfractaldimension,Lyapunovindex,theintrinsiccomplexityofthesystemonsuchconditionhasbeenstudied,andresultofthenumericalsimulationprovesthetheoryofthispapercorrect.

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简介：Highspatialfrequencylaserinducedperiodicsurfacestructures(HSFLs)onsiliconsubstratesareoftendevelopedonflatsurfacesatlowfluencesnearablationthresholdof0.1J/cm2,seldomonmicrostructuresormicrogroovesatrelativelyhigherfluencesabove1J/cm^2.ThisworkaimstoenrichthevarietyofHSFLs-containinghierarchicalmicrostructures,byfemtosecondlaser(pulseduration:457fs,wavelength:1045nm,andrepetitionrate:100kHz)inliquids(waterandacetone)atlaserfluenceof1.7J/cm^2.TheperiodofSi-HSFLsintherangeof110–200nmisindependentofthescanningspeeds(0.1,0.5,1and2mm/s),lineintervals(5,15and20μm)ofscanninglinesandscanningdirections(perpendicularorparalleltolightpolarizationdirection).ItisinterestinglyfoundthatbesidesnormalHSFLswhoseorientationsareperpendiculartothedirectionoflightpolarization,bothclockwiseoranticlockwiserandomlytiltedHSFLswithamaximaldeviationangleof50°ascomparedtothoseofnormalHSFLSsarefoundonthemicrostructureswithheightgradients.RamanspectraandSEMcharacterizationjointlyclarifythatsurfacemeltingandnanocapillarywavesplayimportantrolesintheformationofSi-HSFLs.ThefactthatnoHSFLsareproducedbylaserablationinairindicatesthatmoderatemeltingfacilitatedwithultrafastliquidcoolingisbeneficialfortheformationofHSFLsbyLALs.Onthebasisofourfindingsandpreviousreports,asynergisticformationmechanismforHSFLsathighfluencewasproposedanddiscussed,includingthermalmeltingwiththeconcomitanceofultrafastcoolinginliquids,transformationofthemoltenlayersintoripplesandnanotipsbysurfaceplasmonpolaritons(SPP)andsecond-harmonicgeneration(SHG),andmodulationofSi-HSFLsdirectionbybothnanocapillarywavesandthelocalizedelectricfieldcomingfromtheexcitedlargeSiparticles.