简介：“60秒科学”是一个电台节目，用一分钟的时间为大家带来新鲜、有趣的科学新闻，听众只需花一分钟便能轻松掌握科技发展新方向。一直有关注“60秒科学”的同学是不是发现好久没听到Steve哥哥的声音了？呵呵这就为大家送上咯——大哥出来果然不一样，报道也特别生动震撼啊!Gotaminute？

简介：1958年4月15日。楚雄彝族自治州成立。千里彝山，迎来了交通事业大发展时期。经过彝州各族儿女60年奋力铸造，基本形成公路、铁路、水运、管道、航空5种交通运输方式协调发展的滇中现代交通枢纽。

简介：“60秒科学”是一个电台节目，用一分钟的时间为大家带来新鲜、有趣的科学新闻，听众只需花一分钟便能轻松掌握科技发展新方向。害怕数学考试的同学听好了——做数学题时嘴里念念有词或者用图形来帮助解题能提高答题正确率哦!

简介：WecollectedacornsfromselectedQuercusroburandQuercuspetraeamothertreesgrowingatstationswithdifferentdepthstothewatertable.Weproducedpairsofmicro-cuttingsfromthesesingleacorns.Theobtainedpairsofcuttingsrepresentedphenotypesofhighsimilarityaccordingtophotosyntheticparameters.Thesepairsofcuttingswereusedtotesttheplasticityofresponsetocontrastingwaterregimes.Foreachpair,onecuttingwassubmittedtodroughtandtheotherwassubmittedtowaterlogging.Droughtresponsewasrecordedaccordingtogasexchangetraits（stomatalclosureandwateruseefficiency）.TheresponsetowaterloggingwasrecordedaccordingtothecapacitytoformhypertrophiedlenticelsandtomaintaintheCO2assimilationrate.Intermediaryphenotypespresentingbothhighwateruseefficiencyandthecapacitytodevelophypertrophiedlenticelswereexpected.

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简介：Amicroturbo-expandercapableofhighworkingspeedwasspeciallymanufacturedforuseinanorganicRankinecycle(ORC).Aseriesoftestswereexecutedtoexaminetheperformanceofthemachine.Intheexperiment,themachinewastestedunderdifferentinletpressureconditions(0.2-0.5MPa).Datasuchasthecompressedairpressure,temperaturesoftheinletandtheoutlet,rotationalspeed,andelectricpowergenerationwereanalyzedtodiscoverunderlyingrelationships.Duringthetest,therotationalspeedofthemachinereachedashighas54000r/min,thepeakvalueofthetemperaturedropbetweentheinletandtheoutletreached42℃,themaximumelectricpowergeneratedbythemotor-generatorattachedtothemachinereached630W,andtheefficiencyofthemachinereached0.43.

简介：AnovelopticalfibersensorwithaU-shapedmicro-groovestructureablatedbyfemtosecondlaseronsingle-modefi-berformeasuringairrelativehumidity（RH）isreportedinthispaper.Inordertoimprovetheaccuracyofsensor,agrapheneoxide（GO）/polyvinylalcohol（PVA）compositefilmiscoatedonthesurfaceofmicro-groovestructure.IntheU-shapedmicro-groovestructure,theremainingcoreandmicro-cavityinthemicro-groovemakeuptwomajorop-ticalpropagationpaths,formingaMach-Zehnderinterferometer（MZI）.ThesensorhasagoodlinearresponsewithintheRHrangeof30%--85%,andthemaximumsensitivitycanreach0.6381mrd%RH.Theeffectoftemperatureontheoverallperformanceofthehumiditysensorisalsoinvestigated.Asanewtypeofall-fiberdevice,thesensorshowsexcellentsensitivityandstability.

简介：Inthispaper,aclustermodelinparticleflowcodewasusedtosimulategranitespecimensafterheattreatmentunderuniaxialcompression.Theresultsdemonstratedthatmicro-cracksarerandomlydistributedinthespecimenwhenthetemperatureisbelow300?C,andhavepartialcoalescencewhenthetemperatureisupto450?C,thenformmacro-crackswhenthetemperatureisabove600?C.Thereismoreinter-granularcrackingthanintra-granularcracking,andtheirratioincreaseswithincreasingtemperature.Themicro-cracksarealmostconstantwhenthetemperaturedecreasesfrom900?Ctoroomtemperature,exceptforquartzα–βphasetransitiontemperature(573?C).Thefractureevolutionprocessisobviouslyaffectedbythesecracks,especiallyat600–900?C.Elevatedtemperatureleadstoeasilydevelopeddisplacementbetweenthegrains,andthecapacitytostorestrainenergybecomesweaker,correspondingtotheplasticityofgraniteafterheattreatment.

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简介：OnthebasisoftheinsitudataofDO2,pH,SiO2.PO4-P,NO3-NandNO2-NcollectedinthenorthoftheEastChinaSeaduring1987-1988,thefollowingpointsaremainlyexpounded.1.TheinorgonicnutrientsareobviouslyaffectedbycontinentrunoffinthenorthoftheEastChinaSea.Theirdistributionsarecharacteristicofitsdistributionofterrigenousmaterials.2.TherearethreetransportpathsofnutrientsfromtheshelftotheKuroshioarea.Thefirstismixing-diffusing-advec-tionandupwellingprocess,theprocessofbiologyandbiochemistrybelongstothesecond,andthesinkingprocessisthelastone.3.TheswingoftheKuroshioaxisaffectesboththerangeofthemigrationofsubstancesthroughmixing-diffusing-advec-tionprocessandtheupwellingdegreeofthesubsurfaceKuroshiowatertotheshelf.4.MostpartofthesubstancessinkasmacroparticlestothedeeplayerbeforereachingtheKuroshioarea.

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简介：Thenonlineardynamicandstaticdeflectionofamicro/nanogyroscopeunderDCvoltagesandbaserotationareinvestigated.Thegyroscopeundertakestwocoupledbendingmotionsalongthedriveandsensedirectionsandsubjectedtoelectrostaticactuationsandintermolecularforces.Thenonlineargoverningequationsofmotionforthesystemwiththee?ectofelectrostaticforce,intermoleculartractionsandbaserotationarederivedusingextendedHamiltonprinciple.Underconstantvoltage,thegyroscopefindsthepreformedshape.First,thedeflectionofthemicro/nanogyroscopeunderelectrostaticforcesisobtainedbystaticanddynamicanalyses.Furthermore,thestaticanddynamicinstabilityofthesystemareinvestigated.Afterwardtheoscillatorybehaviorofthepre-deformedmicro/nanogyroscopearoundequilibriumisstudied.Thee?ectsofintermolecularandnonlinearparametersonthestaticanddynamicdeflection,naturalfrequenciesandinstabilityofthemicro/nanogyroscopearestudied.Thepresentedmodelcanbeusedtoexactlydeterminestaticandthedynamicbehaviorofvibratorymicro/nanogyroscopes.

简介：X光检查同轴的阶段对比成像微弱地启用吸收标本与高分辨率和定义成功地被想象。在这篇论文，我们使用计算机模拟方法分析每个参数怎么影响图象的质量。它能避免在实验期间浪费不必要的时间和材料得到理想的图象。

简介：Micro-poredCA6-MAlightweightmaterialwithCA6:MAmassratioof7:3waspreparedusingAl（OH）3.MgCO3andCaCO3asstartingmaterials,andanthracite.sweetpotatostarchandanthracite+sweetpotatostarchasporeformingagent（PFA）withanadditionof10mass%.20mass%and30mass%.respectively.Thestartingmaterialsweredrymixed.wetco-milledinaballmillfor1h.slipcastintocylindricalspecimenswithadiameterof60mm.andthencalcinedat1450℃for3h.WiththeincreaseofPFAaddition.apparentporosityincreases,andbulkdensitydecreases.TheinfluenceofdifferentPFAsonpropertiesofthemicro-poredLWCA6-MAaggregatewasinvestigated.TheachievedCA6-MA.byadding30%sweetpotatostarch.hasaporosityof76.8%.bulkdensityof0.78g·cm-3andmedianporesizeof1.90μm.

简介：SmOHCO3micro/nanoparticleswerepreparedinwater/oil(W/O)reversemicroemulsioncomposedofcetyltrimethylammoniumbromide(CTAB),n-octane,n-butanol,Sm(NO3)3·6H2Oandureaaqueoussolutionbythecouplingrouteofhomogeneousprecipitationwithmicroemulsion.ThenanoparticleswerecharacterizedandanalyzedbyX-raypowderdiffraction(XRD),thermalgravimetricanddifferentialthermalgravimetricanalysis(TG-DTG),Fouriertransforminfraredabsorptionspectra(FT-IR)andscanningelectronmicroscope(SEM).TheresultsshowedthatthephaseSmOHCO3micro/nanoparticleswasinagreementwithpureorthorhombicphase.ThedifferentmorphologiesofSmOHCO3micro/nanoparticleswithgoodmonodispersityandsizewereobtainedbyregulatingthereactiontemperatureandreactiontime.PossibleformationmechanismsofthemorphologicalstructureofSmOHCO3wereproposedanddiscussed.

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简介：摘要下腰疼痛正在成为目前影响人们生活质量的重要因素，其发病的年龄越来越趋于年轻化，每年因下腰痛带来的社会经济损失巨大。椎间盘退变（intervertebral disc degeneration，IDD）是引起下腰疼的重要原因，在多重因素作用下，椎间盘组织出现生物力学和结构的变化，发生纤维环破裂、髓核组织突出，使脊髓和神经根受压，从而引起患者出现下腰疼。微小RNA（Micro-RNA，miRNA）是一类长度为18~24个核苷酸序列的单链非编码小分子RNA，其在真核生物中广泛存在，作为基因表达的重要调控分子之一，已被证明在许多种疾病起始及进展阶段发挥着关键作用，故认为其可能在椎间盘退变中也发挥着重要的作用。目前，临床上针对IDD的治疗手段主要以手术治疗缓解临床症状为主，即使当前手术治疗可以取得良好的疗效，但是手术治疗会给患者带来更大的身体创伤和经济负担。miRNA在椎间盘退变过程中的作用是当前学术界研究的热点之一，研究表明miRNA在退变的椎间盘组织中呈现异常的表达模式，参与IDD的多种病理过程。目前，一些miRNA已被证明与椎间盘退变过程中的多种病理过程有关，包括髓核细胞凋亡和增殖、细胞外基质的降解、细胞自噬、炎症反应及软骨终板的退变等。基因芯片对比研究显示一些miRNA在退变髓核细胞中的表达与正常髓核细胞存在明显差异，这些差异表达的miRNA通过调控其各自的上、下游通路可能参与髓核细胞退变的进程，调控通路多有交叉并行，构建出一个庞大的miRNA调控网。了解miRNA在发病过程中的靶基因和机制，能够在疾病的起源、发展和预后等方面提供重要参考。因此，综述了miRNA在椎间盘退变过程中的重要作用和潜在的临床治疗意义。随着对miRNA研究的深入，通过了解椎间盘退变的分子生物学机制，可以为IDD的诊断和治疗提供新思路，非常有可能成为IDD生物学治疗的新策略。

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简介：Westudiedthecoupleddynamicbehaviorofaquartz-crystal-resonator(QCR)/microbeamssysteminthethickness-shearmotions.Throughtakingintoaccountthecouplestressinthedynamicequationsofthequartzplate,bothcontinuousconditionsofshearforceandbendingmomentattheresonator/micro-beamsinterfacearerealized.FrequencyshiftofthecompoundQCRsysteminducedbymicro-beamsisstudiedindetail.Theobtainedresultsareusefulindevicedesignandfrequency-stabilityanalysisofquartzcrystalresonators.