简介：睡眠与健康工作和学习的关系甚为密切。良好的睡眠，可调节生理机能，维持神经系统的平衡，是生命中的重要一环。缺乏睡眠对中学生的学习、生活会有一定的消极影响，所以学生应当合理地安排自己的睡眠时间。

简介：ThiscommentaryisbasedontheworkofCooper,Davis,andVanVliet(2016)andthecommentaryfocusesonwhatproblemhigh-frequencytradingposes.Itlistskeyliteratureonhigh-frequencytradingthatismissingandpointsoutthatthepokeranalogytodefenddeceptioninfinancialmarketsisweakandmisleading.Thearticleelaboratesonthenegativeimpactcreatedbyspoofingandquotestuffing,thetwotypicaldeceptivepracticesusedbyhigh-frequencytraders.Therecentregulationsregardinghigh-frequencytrading,inresponsetothe“FlashCrash”of2010,arepreventive,computerizedandmoreeffective.Theyreflectethicalrequirementstomaintainfairandstablefinancialmarkets.

简介：Thehighpressureequationofstateforcarbonisconstructedbysomesimplephysicalmodels.Forsolidstate,amultiphaseequationofstateisconsidered,whichincludesfoursolidstates.Forliquidstate,theliquidperturbationtheoryofCRISmodelisused.Inthehightemperature,theelectroniccontributionisobtainedbytheionizationequilibriumtheory.Theresultofourcalculationbasedontheabovemodelsiscomparedwiththefirstprincipledensityfunctionalcalculationandtheothermodels.TheHugoniotandthephasediagramofcarbonarealsocomparedwiththeexperiments.Theresultsaresatisfactory.

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简介：Decreasingtherisksandgeohazardsassociatedwithdrillingengineeringinhigh-temperaturehigh-pressure(HTHP)geologicsettingsbeginswiththeimplementationofpre-drillingpredictiontechniques(PPTs).ToimprovetheaccuracyofgeopressurepredictioninHTHPhydrocarbonreservoirsoffshoreHainanIsland,wemadeacomprehensivesummaryofcurrentPPTstoidentifyexistingproblemsandchallengesbyanalyzingtheglobaldistributionofHTHPhydrocarbonreservoirs,theresearchstatusofPPTs,andthegeologicsettinganditsHTHPformationmechanism.OurresearchresultsindicatethattheHTHPformationmechanisminthestudyareaiscausedbymultiplefactors,includingrapidloading,diapirintrusions,hydrocarbongeneration,andthethermalexpansionofporefluids.Duetothismulti-factorinteraction,acloudofHTHPhydrocarbonreservoirshasdevelopedintheYing-QiongBasin,butonlytraditionalPPTshavebeenimplemented,basedontheassumptionofconditionsthatdonotconformtotheactualgeologicenvironment,e.g.,Bellotti’slawandEaton’slaw.Inthispaper,wefocusontheseissues,identifysomechallengesandsolutions,andcallforfurtherPPTresearchtoaddressthedrawbacksofpreviousworksandmeetthechallengesassociatedwiththedeepwatertechnologygap.Inthisway,wehopetocontributetotheimprovedaccuracyofgeopressurepredictionpriortodrillingandprovidesupportforfutureHTHPdrillingoffshoreHainanIsland.

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简介：Wepresentahighlyefficientmethodofgeneratingandshapingellipseperfectvectorbeams(EPVBs)withaprescribedellipseintensityprofileandcontinuouslyvariantlinearpolarizationstate.Theschemeisbasedonthecoaxialsuperpositionoftwoorthogonallypolarizedellipselaserbeamsofcontrollablephasevortexservingasthebasevectorcomponents.Thephase-onlycomputer-generatedhologramisspecificallydesignedbymeansofamodifiediterationalgorithminvolvingacomplexamplitudeconstraint,whichisabletogenerateanEPVBwithhighdiffractionefficiencyinthevectoropticalfieldgenerator.WeexperimentallydemonstratethattheefficiencyofgeneratingtheEPVBhasanotableimprovementfrom1.83%intheconventionalcomplexamplitudemodulationbasedtechniqueto11.1%inourmethod.WealsodiscussanddemonstratethesimultaneousshapingofmultipleEPVBswithindependenttunableellipticityandpolarizationvortexinbothtransversal(2D)andaxial(3D)focusingstructures,provingpotentialsinavarietyofpolarization-mediatedapplicationssuchastrappingandtransportationofparticlesinmorecomplexgeometriccircumstances.

简介：Inthispaper,wereviewthestatusofthemultifunctionalexperimentalplatformattheNationalLaboratoryofHighPowerLaserandPhysics(NLHPLP).Theplatform,includingtheSG-IIlaserfacility,SG-II9thbeam,SG-IIupgrade(SG-IIUP)facility,andSG-II5PWfacility,isoperationalandavailableforinterestedscientistsstudyinginertialconfinementfusion(ICF)andabroadrangeofhigh-energy-densityphysics.Thesefacilitiescanprovideimportantexperimentalcapabilitiesbycombiningdifferentpulsewidthsofnanosecond,picosecond,andfemtosecondscales.Inaddition,theSG-IIUPfacility,consistingofasinglepetawattsystemandaneight-beamnanosecondsystem,isintroducedincludingseverallasertechnologiesthathavebeendevelopedtoensuretheperformanceofthefacility.RecentdevelopmentsoftheSG-II5PWfacilityarealsopresented.

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简介：Na离子电池由于他们的低费用和自然许多Na资源为大规模精力存储系统被认为一种有希望的选择到Li离子电池。大努力全球正在做为Na离子电池开发高效的电极材料，它为Na离子电池是批评的。这评论基于Na存储机制为Na离子电池提供阳极材料的全面概述：基于插入的材料，基于合金的材料，基于变换的材料和器官的composites。并且我们总结那些阳极材料的Na存储机制并且讨论他们的失败机制。而且，与那些阳极联系的问题和挑战被指出，并且可行策略为设计高效的阳极材料被建议。根据研究的当前的状态，尽管实质的进步被获得了，为为Na离子电池的合适的阳极材料的搜索仍然是挑战性的。不过，我们相信高效的Na离子电池在不久的将来将为在大规模精力存储系统的实际应用程序是有希望的。

简介：有由于季风系统的复杂性在中国预言植被回答到东方亚洲季风(电动会计记帐机)可变性的简单方法的缺乏。在这研究，我们发现了变化西方的和平的副热带的高度(WPSH)是EAM的主要部件之一，在中国在植被生长上有深刻影响。当WPSH更被定位到它的气候一般水准的西方时，东方、西北的部分分别地由0.3%-2.2%，和0.2%-2.2%经历增加的每年一般水准的规范的差别植被索引(NDVI)和粗野主要生产率(GPP)。相反，当WPSH更被定位到它的气候的东方时，平均，上述区域分别地在0.4%～1.6%，和1.3%～4.5%经历减少的每年一般水准的NDVI和GPP。WPSH用作一个主要发行量索引预言植被的反应到季风。

简介：In2018,thejournalHighPowerLaserScienceandEngineeringproducedaSpecialIssueonFibresforHighPowerLasers.Nowadays,fibre-basedlasersourceshavefoundextensiveapplicationsbothinindustryandinscientificresearch.Thescopeofthespecialissuewastospanthelatestdevelopmentsonthefastdevelopingfibre-basedhigh-powerlasersandamplifiers.Thetopicsinvitedforinclusionwere: