学科分类
/ 25
500 个结果
  • 简介:有许多人认为是爱迪生一手创造了二十世纪。虽然有不少人可能有不同的看法,但有一件事是无法否认的,爱迪生是个天才,他的发明深刻地影响了现代社会的发展。有人做过统计:爱迪生一生中的发明,在专利局正式登记的有1300种左右。1881年是他发明的最高纪录年。这一年,他申请立案的发明就有141种,平均每三天就有一种新发明。他活到84岁,一生中的发明有1100项之多。

  • 标签: 中学 英语 课外阅读 阅读材料
  • 简介:基于对教学内容和学情的分析,本课做出如下定位。从主题意义上,在对事件发展脉络的理解基础上,侧重挖掘'蝴蝶效应'在堵车事件中的规律和意义;从思维品质上,侧重于帮助学生1从具体事件中抽象和归纳规律、建构新概念的能力;2比较分析行为背后心理的能力;3辨析现象,利用规律分析问题或解决问题的能力;从价值观上,侧重于学生自己思考个体角色在事件中的意义,从而反思自己的社会角色和行为。

  • 标签: 交通拥堵 疏散 蝴蝶效应
  • 简介:PbSnanoparticlesmodifiedbyapolymer(P-PbS)wasprepared,andthetransientnonlinearopticalpropertiesstudiedbyfemtosecondopticalKerreffect(OKE)spectroscopyforthefirsttime.Averylargenonlinearopticaleffect(X^(3)-5.6×10^-12esu)withresponsetimecomparabletothelaserpulse(-165fs)wasobserved.ComparingwithPbSnonoparticlesstabilizedwithPVAandcoatedwithsodiumdodecylebenzenesulphonate(DBS).theopticalnonlinearityofthePbSnanoparticlesmodifiedbythepolymerismuchlargerthanthoseofthem.Thereafter.thecorrespondingnonlinearitymechanismwasinterpreted.

  • 标签: PbS纳米颗粒 非线性光学效应 实验
  • 简介:课文选自Beijinger杂志,作者为在北京生活的外国人。文章描述了作者亲身经历的交通拥堵。文章巧妙地选用'TheButterflyEffect'作为标题,是对文中交通拥堵与疏散的过程的高度总结与提升。文章语言地道、形象、生动,通过动词词组的学习学生能感受到人物的情绪与态度。本课中学生通过文本解析,进行信息提取、诠释的同时,学会用所学的知识解释现实生活中的蝴蝶现象并反思自己的行为,理解做好个人角色的价值和意义。

  • 标签: 交通拥堵 疏散 蝴蝶效应
  • 简介:Theangularaccelerationduetothespineffectincreasestheburningrateofsolidpropellantandchangesthemotorperformancebyincreasingtheoperatingpressureanddecreasingtheburningtime.Soitisimportanttoknowthegrainregressiontakenplaceinthesolidpropellantrocketmotorintheaccelerationfield.Thisstudyrepresentsthegrainregressionanalysisoftwo-dimensionalaxis-symmetricstargrainconfigurationofthesolidpropellantrocketmotorwithspininducedaccelerationeffectandpressureeffectonburnrateusinggeometricalandnumericalanalysis.Whiletherocketisspinning,theburnratesoneachpointofthepropellantsurfacearedifferentwithitsradialdistance,accelerationvectorangleandsurfaceslope.Withthedifferentburnratesonthepropellantsurface,weanalyzethepropellantsurfaceperimeterandportarea,andtheseresultsarecomparedwiththoseofconstantburnrateandburnrateaffectedbythechamberpressure.

  • 标签:
  • 简介:药的效果的研究,kanamycin,在recombinantEscherichiacoli的生长新陈代谢上,B1被对待的细胞的新陈代谢的活动监视的microcalorimeter执行。种recombinantEscherichiacoli房间暂停的力量时间曲线,与不同kanamycin剂量对待,被记录。效果的程度被变化在microcalorimetric曲线的斜坡评估,药行动的动力学从这些变化在到达了他们的最大的价值并且维持了他们的最大的价值的时间被解释。试验性的剂量效果关系遵循集体行动的法律的中部效果的原则:fa/(1?fa)=(D/D50)m。y=lg的一个阴谋[(fa)1?1]?1对x=lgD给斜坡m,D50和R。试验性的结果表明kanamycin的高集中在lg阶段在recombinantEscherichiacoliB1的生长上有禁止的效果,并且在静止时期有支持的效果。而且,microcalorimetry是为在生物学的调节效果的察觉的一个可靠方法,这被表明。

  • 标签: 卡那霉素 微量热法 药效评价 重组大肠埃希氏菌 中效原理 剂量效应
  • 简介:BasedonthesurveydataoftypicalvillagesinShaanxiProvince,China,theeffectofsocialcapitalontheincomegapoffarmers’householdswasanalyzedusingtheShapleyvalueofthetotalamountofsocialcapitalandthesocialcapitalstructure.Theresultsshowthefollowing:first,socialcapitalcanexpandthehouseholdincomegap,andtheeffectofthisindexonthehouseholdincomegapis7.54%.Second,theindexesofthesocialcapitaldimensioncanexpandthehouseholdincomegap,andthestructuraleffectsofthehouseholdincomegaponsocialnetworks,socialtrust,andsocialparticipationare3.17%,3.64%,and0.65%,respectively.Third,nodimensionofthepathisthesameastheeffectonthehouseholdincomegap.

  • 标签:
  • 简介:effectn.结果,效力【经典例句】Hisnewwayofteachingproducedagoodeffect.他的新教学方法产生了良好的效果。Thishadagreateffectupon/onthefutureofbothmotherandson.这对母子俩的将来影响很大。

  • 标签: 用法 经典例句 GOOD 教学方法 This BOTH
  • 简介:对Escherichiacoli和克积极的葡萄球菌aureus微生物的polyaniline(PAni)的优秀抗菌剂性能在黑暗、可见的轻条件下面被表明了。在PAni分子和细菌之间的静电的坚持可以为PAni的抗菌剂反应起一个很重要的作用,由于我们的调查,进行PAni,它的composites/blends被相信作为抗菌剂代理人的一种新类型有用,为改进人的健康和生活环境的自我清洗以及多功能的材料。

  • 标签: 聚苯胺 导电聚合物 抗菌效果 大肠杆菌 生物材料
  • 简介:Theeffectoftemperatureonthecriticalaggregateconcentration(CAgC)hasbeeninvestigatedforthefirsttime,bymeasurementofthehydrolyticrateconstantsofp-nitrophenyldodecanoate(C12)andhexadecanoate(C16)atdifferenttemperaturesinthe30:70V/V(Φ=0.30)and40:60V/V(Φ=0.40)dioxane(DX)-H2Osystems.TheCAgCvaluesofC12andC16increasewiththeincreaseofthetemperature,i.e.,hightemperaturesdisfavoraggregation.ActivationenergiesforthehydrolysisofC12inthemonomericandaggregatedconcentrationdomainshavealsobeendiscussed.

  • 标签: TEMPERATURE ACTIVATION ENERGY CAgC CN aggregation.
  • 简介:Wefurtherconsidertheeffectofrodstrengthbyemployingthecompressiblepenetrationmodeltostudytheeffectofcompressibilityonhypervelocitypenetration.Meanwhile,wedefinedifferentinstancesofpenetrationefficiencyinvariousmodifiedmodelsandcomparethesepenetrationefficienciestoidentifytheeffectsofdifferentfactorsinthecompressiblemodel.Tosystematicallydiscusstheeffectofcompressibilityindifferentmetallicrod-targetcombinations,weconstructthreecases,i.e.,thepenetrationsbythemorecompressiblerodintothelesscompressibletarget,rodintotheanalogouslycompressibletarget,andthelesscompressiblerodintothemorecompressibletarget.Theeffectsofvolumetricstrain,internalenergy,andstrengthonthepenetrationefficiencyareanalyzedsimultaneously.Itindicatesthatthecompressibilityoftherodandtargetincreasesthepressureattherod/targetinterface.Themorecompressiblerod/targethaslargervolumetricstrainandhigherinternalenergy.Boththelargervolumetricstrainandhigherstrengthenhancethepenetrationoranti-penetrationability.Ontheotherhand,thehigherinternalenergyweakensthepenetrationoranti-penetrationability.Thetwotrendsconflict,butthevolumetricstraindominatesinthevariationofthepenetrationefficiency,whichwouldnotapproachthehydrodynamiclimitiftherodandtargetarenotanalogouslycompressible.However,ifthecompressibilityoftherodandtargetisanalogous,ithaslittleeffectonthepenetrationefficiency.

  • 标签: COMPRESSIBILITY HYPERVELOCITY PENETRATION EQUATION of state
  • 简介:OlympicslogisticsnetworkaspreparationIn2003,theBeijingmunicipalgovernmentproposedtheblueprintforthreekeylogisticsprojectsforthe2008Olympics.Itplannedtobuildthreelogisticsbases(atYancuninFangshanDis-trict,MajuqiaoinTongzhou,andShaheinChangpingDistrict)alongwithtburlogisticscenters(atTianzhuinChaoyang,Shiba-jiadianinChaoyang,DazhuanginDaxing,andMentougou).Anumberofspecializeddistributioncentershavealsobebuiltto

  • 标签: 北京奥运会 后勤学 后勤工作 政府管理
  • 简介:Theanalyticalmethodoftotalresourcereallocationeffectisanevolutionoftheanalyticalmethodofthefactorsofeconomicgrowth.SincethemarketizationreforminChinain1978,marketmechanismhasplayedamoreandmoreimportantroleinresourceallocation,andChineseeconomyhasdevelopedgreatly,whichiscalled'theChineseMiracle'.ThispaperanalyzestheeconomicgrowthinChinafrom1978to2004withtheanalyticalmethodoftotalresourcereallocationeffect.Theresultshowsthattheannualgrowthrateoftotalresourcereallocationeffectwas0.2%,whichwas5.1%ofthecomprehensiveproductivityand0.21%ofthegrossoutputgrowth,i.e.thetotalresourceallocationplayedaweakroleintheeconomicgrowthinChina.WhenanalyzingitinChenery'smultinationalmodel,wefindthatChinesecomprehensiveproductivitygrowthratewashigherthanthatinalltheincomephasesofthemodel,butthetotalresourceallocationeffectwasobviouslylowerthanthatinalltheincomephasesofthemodel.ItindicatesthatthetotalresourceallocationinChinahasagreatpotential,andthattoacceleratemarketizationreformisoneoftheimportantissuesforChineseeconomicdevelopment.

  • 标签: 中国 经济增长 整体资源分配 资源管理
  • 简介:AThepurposeofthisinvestigationwastostudythetherapeuticeffectofLamivudineonHBVDNAinperipheralbloodmononuclearcells(PBMC)andserum,andthelevelofcytokinesinserumofthepatientswithchronichepatitisB.Thepatientsweredividedintotwogroups(A=47,B=34),andtreatedbyLamivudine,routinemedicine,respectively.ThelevelsofHBV-DNAinPBMCandserumandcytokineswerealldetectedbeforeandaftertreatment.AfterthetreatmentofLamivndinefor36weeks,thetotalconversionnegativeratesofHBV-DNAinPBMCandserumofthepatientstreatedwithLamivudinewere55.32%(26/47)and61.70%(29/47),respectively.ThetotalnegativeconversionratesofHBV-DNAinPBMCandserumofthepatientstreatedbyroutinemedicinewere26.47%(9/34)and32.35%(11/34),respectively.TherewassignificantdifferencebetweenLamivudinegroupandroutinemedicinegroup(P<0.01).ThenegativeconversionratesofHBeAginserumofthepatientswere46.81%(22/47)and68.09%(32/47)attheendof24weeksand36weeks,andwerehigherthanthoseofroutinemedicinegroup(P<0.05andP<0.01).Thelevelsofalanineaminotransferase(ALT),aspartateaminotransferase(AST),ALT/ASTinserumofthepatientsafterbeingtreatedbyLamivudine,routinemedicineweredown-regulatedto(30.1±9.6)U/ml,(32.3±10.7)U/ml,0.9±0.1and(48.4±10.7)U/ml,(44.7±11.0)U/ml,1.1±0.2.Aftertheanalysisofvariance,thehighsignificantdifferencewasobviousbetweenthetwogroups(P<0.01).ItwasduetothehighlevelsofIL-6,IL-8andTNF-αinchronichepatitisBwhichcouldbedown-regulatedto(250.5±33.3)pg/ml,(153.4±22.2)pg/ml,(232.6±21.2)pg/mlbyLamivudine,whichwasmoreobviousthanthatofroutinemedicine(P<0.01).LamivudinehashightherapeuticeffectonthetreatmentofHBVDNAinPBMCandserumandhasbettertherapeuticeffectthanthatofroutinetherapy.Lamivudinemayalsohavehigherdown-regulatedinflammatoryinfiltrationandsecretioninlocalsitecaused

  • 标签: 细胞因子 乙型肝炎病毒 诱导因素 临床
  • 简介:Inthepaper,theturbulentdissipationisconsideredinthemodelforstudyingtheflowovermountains.Thegoverningequationisafirstorderordinarydifferentialequationderivedfromanalgebraicequationwithoutdissipationcase.Thesolutionissensitivetotheupstreamconditionofdissipation.Thedissipationnotonlyreducesthestrengthofdiscontinuitybutalsochangesthepropertiesofthegoverningequation.Inthepaper,thequalitativecharacteristicfeaturesofthegoverningequationarediscussed.Thenumericalresultswithsuperandsub-criticalcasesarealsodiscussedindetail.Theresultsshowthattheturbulentdissipationisanimportantfactorandisnotnegligible.

  • 标签: TURBULENT DISSIPATION FLOW OVER MOUNTAINS governing