简介：AstudentsuicidelastWednesdayinGuangzhouhasnotonlymadethevictim'sfamilysadbuthasshowntheseriousnessofdepressionandmentalfragilityamongstudents.

简介：Airpressureistheforceexertedonyoubytheweightoftinyparticlesofair(airmolecules).Althoughairmoleculesareinvisible,theystillhaveweightandtakeupspace.Sincethere’salotof"empty"spacebetweenairmolecules,aircanbecompressedtofitinasmallervolume.

简介：Basedontheformerresearchworkoftheauthors,theresistanceofdifferentsolidparticlesuspensionflowinaverticalpipeisanalysed,andinvestigatedexperimentally.Theapplicableformulasofpressuredroparepresented.Twotypesofpar-ticles,talcumpowderandglassbeads,areconvcyedinthetestwhichhasbeencarriedoutatvariousairvclocitiesof10to28m/sandattheratioofsolids-airmassflowraterangedfrom0to2.Theexperimentalresultsshowagoodagreementwiththecalculatedones.

简介：Bridgepressureflowscouratclearwaterthresholdconditionisstudiedtheoreticallyandexperimentally.Theflumeexperimentsrevealthatthemeasuredscourprofilesunderabridgearemoreorless2-dimensional;allthemeasuredscourprofilescanbedescribedbytwosimilarityequations,wherethehorizontaldistanceisscaledbythedeckwidthwhilethelocalscourbythemaximumscourdepth;themaximumscourpositionislocatedjustunderthebridgeabout15%deckwidthfromthedownstreamdeckedge;thescourbeginsataboutonedeckwidthupstreamthebridgewhilethedepositionoccursatabout2.5deckwidthsdownstreamthebridge;andthemaximumscourdepthdecreaseswithincreas-ingsedimentsize,butincreaseswithdeckinundation.Thetheoreticalanalysisshowsthat:bridgescourcanbedividedintothreecases,i.e.downstreamunsubmerged,partiallysubmerged,andtotallysubmerged.Fordownstreamunsubmergedflows,themaximumbridgescourdepthisanopen-channelproblemwheretheconventionalmethodsintermsofcriticalvelocityorbedshearstresscanbeapplied;forpartiallyandtotallysubmergedflows,theequilibriummaximumscourdepthcanbedescribedbyascourandaninundationsimilaritynumber,whichhasbeenconfirmedbyexperimentswithtwodecksandtwosedimentsizes.Forapplication,adesignandfieldevaluationprocedurewithexamplesispresented,includingthemaximumscourdepthandscourprofile.

简介：目的:探讨在不同表面上跑步对足底压力和胫骨加速度的影响。方法:13位男性跑步者被要求分别在水泥地、塑胶跑道、天然草地、跑步机以及配备EVA缓冲衬垫物的跑步机上以12km/h的速度进行慢跑。用足底压力测试系统和安放在胫骨粗隆的加速度计,记录和分析足底压力与胫骨冲击的特点。结果:第一和第二足底压力峰值(发生时间)、压力时间积分、峰值压力分布在混凝土、塑胶、草地和正常的跑步机的表面间没有明显差异。在5种不同测试表面下,峰值加速度正值也无显著差异。但相比于混凝土表面,在配备EVA缓冲衬垫物的跑步机上跑步能明显减小在冲击阶段的足底压力第一峰值和压力积分(p<0.05)。上述结果可进一步归因为足后跟区域峰值压力下降(P<0.05)。结论:运动表面和下肢冲击之间也许并无必然关系。然而值得注意的是,在解释足底压力的表现及将其运用到陆地表面的跑步运动中时应考虑不同跑步机表面的影响。

简介：Background:Novelplayertrackingtechnologiescanchangetheunderstandingofperformancedeterminantsinteamsportsbyallowingtoaccuratelymeasuringtheactivitydemands.Theaimofthisstudywastoidentifyhowthedefensivepressureaffectsthetime-motionvariablesandthetechnicalactionsinbasketball.Methods:Twentyinternationalmaleplayers(age:16.05±2.09years,weight:73.13±8.10kg,height:183.10±5.88cm)playedtwo10minbasketballquarters,wheretheyusedaman-to-man1/4-courtdefenseuntilthe4thmin(F1/4),changedtoman-to-manfullcourt(FULL)for3minand,fromthe7thtothe10thminreturnedto1/4-courtdefense(S1/4).AcomputerizednotationalanalysiswasperformedusingSimiScoutandpositionaldatawerecapturedwiththeUbisenseRealTimeLocationSystem(meansamplingrate3.74±0.45Hzpertransmitter/player).Results:Thetime-motionvariablespresentedsimilarresultsbetweendefensiveconditions,showingatotaldistancecoveredaround90m/min.However,resultssuggestedpossibleverticaljumpimpairmentsinS1/4periods.Therewasmoredistancecoveredwhilejoggingintheoffensivecourt(38.15±12.17m/minoffensivecourtvs.32.94±10.84m/mindefensivecourt,p<0.05)andmoredistancecoveredwhilerunninginthedefensivecourt(16.41±10.27m/minoffensivecourtvs.19.56±10.29m/mindefensivecourt,p<0.05).Conclusion:Theseresultssuggesthowtoimprovetaskrepresentativenessduringspecificconditioningorgame-basedtrainingsituationsandalsotohelpcoaches’strategicdecisionsduringthegames.

简介：Epoxyresinlaminateontowhichapairofcopperfoilwasprintedwasemployedastestsamples.Thesampleswereplacedinanartificialatmosphericchamber,whichwasvacuumedbyarotarypumpfrom100kPato5kPa.ThemagneticfieldwasproducedbypermanentmagnetsthatwereassembledtomakeE×Bdriftawayfrom,intoandparalleltothesamplesurface,respectively.Magneticfluxdensitywasadjustedat120mT,180mTand240mTrespectively.Byapplyinganegativebiasvoltagebetweentheelectrodes,the...

简介：微尺寸的试管热exchanger(MTHE)被制作，并且它在转移和压力掉的发情的表演试验性地被学习。MTHE试管的方面上的单相的强迫的传送对流热转移关联被建议并且与在雷纳兹数字的以前的试验性的数据相比变化5001800。在计算Nusselt数字的关联的平均偏差是大约6.59%。在热入口区域的入口效果被讨论。在雷纳兹数字的一样的范围，压力落下和磨擦系数被发现比常规关联预言的那些更加高。磨擦因素和雷纳兹数字的产品也高是一个常数，而是大部分比常规。

简介：

简介：超级批评二氧化碳+n-hexanesystem的蒸汽液体平衡数据在313点被测量。15K，333。15K，353。15K，并且373。15K和他们的莫尔体积和密度在批评的潜水艇并且超级临界区域从2两个都被测量。用一个可变卷的压热器的15to12.63MPa。包括系统的莫耳分率，密度，和莫尔体积的热力学的性质被HeiligandFranck，一个排斥术语和一个方形井的潜在的吸引力在称为与状态的一个方程计算因为分子间的相互作用被使用。对明智的联合统治被用来计算方形井的分子的相互作用潜力和三个可调节的参数(ω，k_ε，k_σ)被获得。状态的TheHeilig-Franck方程被发现与二氧化碳+n己系统的二进制vapor-liquidequilibrium数据有好关联。

简介：摘要：传统温压成形过程中由于压力分布不均匀易造成NdFeB粘结磁体各部分密度和强度的不均匀，为提高NdFeB粘结磁体的性能，对温压成形过程中NdFeB粘结磁体进行保压固化。研究表明温压压制粘结NdFeB磁体后，对NdFeB粘结磁体保压固化一段时间，不仅提高磁体的密度和综合磁性能，还可以改善磁体的表面质量。