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如图所示，长为2m、倾斜放置的传送带以2m/s的速度沿顺时针方向匀速转动，传送带与水平方向的夹角为30°，将一个质量为1kg的物块轻放在传送带的底部，同时给物块施加一个平行传送带向上、大小为12N的...
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高三下学期物理《》真题及答案
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如图所示足够长的水平传送带以v0=2m/s的速度匀速运行t=0时刻在左端轻放一质量为m的小滑块t=2
3m/s
2m/s
1m/s
0
如图甲所示倾斜传送带倾角θ=37°两端A.B.间距离为L=4m传送带以4m/s的速度沿顺时针转动一质
如图所示水平传送带长L=2.45m以速度V.1=4m/s顺时针运动倾斜的传送带足够长与水平面的夹角θ
如图所示一长为L=18m的传送带水平放置可以看成质点的物块静止于传送带的左端物块与传送带之间的动摩擦
如图所示物块M.在静止的传送带上以速度v匀速下滑时传送带突然启动方向如图中箭头所示若传送带的速度大小
M.静止在传送带上
M.可能沿斜面向上运动
M.下滑的速度变为2v
M.受到的摩擦力不变
水平传送带以2m/s的速度运行将质量为2kg的工件轻轻放初速度为零在传送带上设传送带速度不变且足够长
如图所示足够长的水平传送带以恒定速率2m/s沿顺时针方向运动在与传送带同一竖直平面内有一四分之一光滑
如图所示为货场使用的传送带的模型传送带倾斜放置与水平面夹角为θ=37°传送带AB长度足够长传送皮带轮
如图所示水平传送带
B.两端相距S.＝3.5m，工件与传送带间的动摩擦因数μ=0.1。工件滑上A.端瞬时速度V
A
＝4 m/s,达到
端的瞬时速度设为V
B
，则（ ） A.若传送带不动，则V
B
=3m/s B.若传送带以速度V=4m/s逆时针匀速转动，V
B
=3m/s
若传送带以速度V=2m/s顺时针匀速转动，V
B
=3m/s
若传送带以速度V=2m/s顺时针匀速转动，V
B
=2m/s
18分如图所示光滑1/4圆弧形槽的底端B.与长L=5m的水平传送带相接滑块与传送带间动摩擦因数为0.
2013南昌铁一中摸底如图所示为粮食仓库中常用的皮带传输装置示意图它由两台皮带传送机组成一台水平传送
如图所示足够长的水平传送带以v0=2m/s的速度匀速运行t=0时刻在左端轻放一质量为m的小滑块t=2
3m/s
2m/s
1m/s
0
如图所示一水平的传送带长为20m以2m/s的速度匀速顺时针转动已知该物体与传送带间的动摩擦因数为0.
2013南昌铁一中摸底如图所示为粮食仓库中常用的皮带传输装置示意图它由两台皮带传送机组成一台水平传送
如图所示的传送带其水平部分ab的长度为2m倾斜部分bc的长度为4mbc与水平面的夹角为α=37°.将
如图所示物块M.在静止的足够长的传送带上以速度v匀速下滑时传送带突然启动方向如图中箭头所示若传送带的
M.下滑的速度不变
M.静止在传送带上
M.先向下减速运动，后向上加速，最后与传送带一起向上运动
M.可能沿斜面向上运动
如图所示水平传送带长L=2.45m以速度V.1=4m/s顺时针运动倾斜的传送带足够长与水平面的夹角θ
如图所示水平传送带左右两端相距L.＝3.5m物块
以水平速度v
0
＝4 m/s滑上传送带左端，物块与传送带间的动摩擦因数μ＝0.1.设A.到达传送带右端时的瞬时速度为v，g取10 m/s
2
，则下列说法正确的是( )A.若传送带速度等于2 m/s，物块一直做减速运动
若传送带速度等于3.5 m/s，v一定等于3 m/s
若v等于3 m/s，传送带一定不能沿顺时针方向转动
若v等于3 m/s，传送带可能静止，也可能沿逆时针或顺时针方向转动
如图所示水平传送带
B.两端相距s=2m，工件与传送带间的动摩擦因数μ=0.4。工件滑上A.端瞬时速度vA=5m／s，达到
端的瞬时速度设为vB，则（ ） A.若传送带以4m/s顺时针转动，则vB=3m/s B.若传送带逆时针匀速转动，则vB<3m/s
若传送带以2m/s顺时针匀速转动，则vB=3m/s
若传送带以某一速度顺时针匀速转动，则一定vB>3m/s
如图水平传送带
B.两端相距S=3.5m，工件与传送带间的动摩擦因数μ=0.1。工件滑上A.端瞬时速度vA=4m／s，达到
端的瞬时速度设为vB，则（ ） A.若传送带不动，则vB=3m／s B.若传送带以速度v=4m／s逆时针匀速转动，vB=3m／s
若传送带以速度v=2m／s顺时针匀速转动，vB=3m／s
若传送带以速度v=2m／s顺时针匀速转动，vB=2m／s
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三氯生X是一种广谱抗菌化合物．广泛添加于肥皂洗手液牙膏洗洁精化妆品沐浴露等个人护理用品中．三氯生的合成路线如图 1E的系统命名为．反应②的反应类型为．F分子中含饭官能团的名称是． 2已知D中不含有氯元素则D的结构简式为． 3反应①的化学方程式为． 4下列有关三氯生X的说法正确的是． A．分子中有7个原子位于同一直线上B．可与水以任意比互溶 C．能与FeCl3溶液发生显色反应D．苯环上的一溴代物有2种 5写出一种满足以下条件的三氯生X的同分异构体的结构简式． ①分子结构中只有1个苯环．且苯环上有4个侧链 ②有3种类型的官能团．其中一种为酚羟基 ③核磁共振氢谱有3组峰．峰面积之比为322 6根据题设信息．设计以甲苯为原料合成的线路其他试剂任选．
设NA为阿伏加德罗常数的值下列说法正确的是
Itstartedwithawomanwhowasn'tdoinganythingparticularlyawfulbutIjustfeltunhappywhenIlookedatthephoto.Icouldn'teventellyouwhatexactlythepicturewasbutIjustrememberthefeelingthatcameoverme:annoyanceandunhappiness. IthappenedagainafewweekslaterwithaphotoofacollegestudentthatIrememberasnotbeingverynice.SuddenlyIdecidedthatI'dhadenough.Idon'tneedtofollowthesepeopleonsocialmedia.WhyamIfloodingmylifewithpeoplethatmakemeunhappy?Iunfollowedher.AndthenIbegantoridmysocialmediaplatformsofpeoplewhodidn'tmakemehappy. Workingasasocialmediastrategist1finditalmostimpossibletogiveupallsocialmediaplatformsbutitalsodidn'tneedtomakemeunhappywheneverIwasonitthroughouttheday.BesidesIlikesocialmediawhenit'sahealthyspaceforme.SoinsteadoftheextremechoiceofgivingitallupIdecidedI'dfillmyfeedwiththepeopleandthingsthatimprovedmymood. Beingselectiveaboutthepeopleyousurroundyourselfwithisimportantforyourhealthandself﹣care.WhenIrealizedhowmuchbetterIfeltwhenIdidn'tseethatbloggerpostvideothatmademerollmyeyesorapicturethatbroughtmetotearsIknewIhadmadetherightdecision. NowmyfeedfillsmewithjoywhenIseemyfriendspostabouttheirphotosandblogsfromwhichIdrawinspiration.Socialmediadoesn'thavetobetheterribleplaceeveryonesaysitisbutyouhavetobewillingtomakethefirstmovetomakeitthatway. 1Howdidtheauthorfeelwhenseeingaphotoofcollegestudent? A.Embarrassed B.Confused C.Upset D.Concerned 2Howdidtheauthordealwithpeopleonsocialmedia? A.Shedidherbesttomakefriendswiththem B.Shewipedoutthosewhomadeherunhappy. C.ShewarnedthemofthedangeronSocialmedia D.Shefeltsorryfornotstayingintouchwiththem. 3Whatmightbeadvisedtodoonsocialmediaaccordingtoothetext? A.Followpeoplewhoposthappythings. B.Learntoenjoyyourfriends'posts. C.Makecommentsafteryourfriendsposts. D.Sharehappinessandsorrowwithyourfriends. 4What'sthemainideaofthetext? A.Changingmyattitudebenefitsmegreatly. B.It'stimetolimitourtimespentonsocialmedia. C.Peoplealwaysmakesmeunhappyonsocialmedia. D.Deletingpeoplefromsocialmediachangesmyfeeling.
工业以软锰矿主要成分是MnO2含有SiO2Fe2O3等少量杂质为主要原料制备高性能的磁性材料碳酸锰MnCO3．其工业流程如图1 1浸锰过程中Fe2O3与SO2反应的离子方程式为Fe2O3+SO2+2H+＝2Fe2++SO42﹣+H2O该反应是经历以下两步反应实现的． ⅰFe2O3+6H+＝2Fe3++3H2Oⅱ… 写出ⅱ的离子方程式． 2过滤Ⅰ所得滤液中主要存在的两种金属阳离子为填离子符号． 3氧化过程中被MnO2氧化的物质有写化学式． 4“浸锰”反应中往往有副产物MnS2O6生成温度对“浸锰”反应的影响如图2所示为减少MnS2O6的生成“浸锰”的适宜温度是向过滤Ⅱ所得的滤液中加入NH4HCO3溶液时温度不宜太高的原因是． 5加入NH4HCO3溶液后生成MnCO3沉淀同时还有气体生成写出反应的离子方程式． 6生成的MnCO3沉淀需经充分洗涤检验洗涤是否完全的方法是．
水系钠离子电池安全性能好价格低廉对环境友好有着巨大的市场前景．右图为某钠离子二次电池工作原理示意图电池反应为2NaFePO4F+Na3Ti2PO432Na2FePO4F+NaTi2PO43．下列说法错误的是
氨气和氯气是重要的工业原料某兴趣小组设计了相关实验探究它们的某些性质．实验一用氨气认识喷泉实验的原理并测定电离平衡常数KNH3•H2O 1检査图1的装置Ⅰ的气密性的方法是． 2喷泉实验结束后发现三颈烧瓶未充满水假如装置的气密性良好原因是．用填仪器名称量取25.00mL喷泉实验后的氨水至锥形瓶中用0.0500mol/L盐酸滴定测定氨水的浓度滴定曲线如图2所示．下列关于该滴定实验的说法中正确的是选填字母． A．当pH＝7.0时氨水与盐酸恰好中和B．选择酚酞作为指示剂测定结果偏低 C．酸式滴定管未用盐酸润洗会导致测定结果偏低D．当pH＝11.0时KNH3•H2O约为2.2×10﹣5 实验二拟用图3装置设计实验来探究纯净干燥的氯气与氨气的反应． 3A中所发生反应的化学方程式为． 4图3中的装置连接顺序为A→→→→→用大写字母表示．若按照正确顺序连接实验装置后整套实验装置存在的主要缺点是． 5写出F装置中的反应的一种工业用途． 6反应完成后F装罝中底部有固体物质生成．请利用该固体物质设计一个实验方案证明NH3•H2O为弱碱其余实验用品自选．
短周期主族元素WXYZ的原子序数依次增大WZ同主族．WXYZ四种元素形成化合物Q25℃时Q溶液的pH＞7．下列说法正确的是
Bytheendoftheyeara3D﹣printedbridgewillbeputtouseinChinaforthefirsttime. Different1traditionalbridgesits2createdesigndoesn'tusereinforcedconcrete.Itismadeofanewmaterial3designtoweatherrainandsunfor4extendedperiodandthat'sdurableenoughtomeetnationalconstructionindustrystandards.Ifpartsofthebridgebecomedamagedtheycanberepaired5separate. The15﹣meter﹣longfootbridgeinShanghai6willhaveservicelifeofupto30yearswilltake35daystobuildaccordingto7itchiefarchitect.Thecomplexcurvedsurfacesofthebridgecanonlybeachievedby8use3Dprintingtechnology.Basedonlaboratorytestingitcanbearaloadof250kilogramspersquaremeter. Thisisn'tthefirsttimethata3D﹣printedbridge9makeinChina.InJulylastyearTongjiUniversityinShanghaimadetheworld'sfirsttwo3D﹣printedpedestrianbridges. 10thatpairofbridgeswasonlybuiltasademonstrationandnotforactualuse.
Thewordtoleranceiswidelyusedinliberaldemocracies自由民主.Itindicatesapositivemeaning.Politiciansurgeustobetoleranttowardsminorities.Educatorsteachustobetoleranttowardstheother.Thepressisfullofreferencestotheneedtodisplaytolerancewhenfacedwithindividualsorgroupsespousingadifferentvieworholdingadifferentreligiousbelief.Atolerantsocietyisanobjectivesoughtafterbyanyonewhobelievesinthevaluesofdemocracy.Atolerantindividualisconnectedwithvirtuousqualities. Thequestionwemustaskiswhetherwehavebeenusingthewordtolerancefullyawareofitsmeaningandwhetherwehaveapplieditcorrectlytoreflectwhatwereallywishtoconvey. Thewordtolerancemeanstobearortobearwith.IfItoleratesomethingorsomeoneIbasicallysaythatIamreadytobearitorhim.Icantolerateabadsmelloranoisyneighbour.TheactoftolerationforcesmetodesistfromconveyingmyobjectiontotheexistenceofaphenomenonwhichIfinddifficulttobear.Abadsmelloranoisyneighbourisconsideredbymetobeanobjectionablephenomenon.BytoleratingeitherofthemIamnottransformingthebadsmellorthenoisyneighbourintopositivephenomena.Let'sbehonest:Idon'thaveadifferenttastewhenitcomestobadsmells.Isimplydislikeitandhopethatitdisappears.Idon'trespectthenoisyneighbour.IwouldratherhavehimstopatoncethenoiseheismakingsoIcanliveinpeace. Thesubjecttoleratingisbynaturenotequaltotheobjectbeingtolerated.IfItolerateyouIessentiallysaythatIamaboveyouandampreparedalthoughunwillinglytobearwithyourpresenceorwithyourpracticesoropinions.Thatmaybetrueinthecaseofanindividualwhoisreadytotoleratetheother.Howeverthisattitudebysuchanindividualthoughempiricallytrueishardlyavirtue.Certainlythefactthatanindividualinrealitymaymerelytoleratetheotherorhisopiniondoesnotjustifyagovernmentoranyofficialauthoritypromotingtoleranceasavirtue.Onecannottolerateanequalbeing.Trueequalityinvolvesrespectnottoleration.Torespecttheotherasadistinctivepersonishardlytotoleratehim.Thisisthetruemeaningofequality:diversityexistinginamutually﹣respectfulsocio﹣legalsetting. Atolerantattitudeinvolvesthegrantofafavournotaright.Thequestionweshouldaskourselvesiswhetherwewouldeverwishaparliamenttomakelawsconsideringusasindividualsandaspartofacollectiveentityorapermissiontopursuecertainactionsinterpretedasafavourratherthanaright?Indeedwouldweeverwishanyonetolistentoourviewsandacceptusthewaywearesimplybecauseheiskindenoughtotolerateus? 1Thefirsttwoparagraphsaremainlyintendedtoshowthat. A.toleranceisasymbolofliberaldemocracies B.democraticsocietyalwaysadvocatestolerance C.people'sunderstandingoftoleranceisone﹣sided D.tolerancecanbeappliedtomanysituations 2Theexampleofabadsmellandanoisyneighbourisraisedtoindicatethat. A.thewriterarefedupwiththem B.mostpeoplefindthemhardtotolerate C.thewriterisn'tprejudicedagainstthem D.toleratingthemisn'tavirtuousact 3ThemainideaofParagraph4isthat. A.toleranceshowsanunequalrelationship B.mostpeoplepromotetoleranceasavirtue C.peopleshouldshowrespectforeachother D.tolerancehasnothingtodowithrespect 4Whichcanbethebesttitleforthispassage? A.ToleranceandRespect B.WhatIstoBeTolerated? C.IsToleranceaVirtue? D.ShouldPeopleBeTolerant?
设NA为阿伏加德罗常数的值．下列说法正确的是
InthewintermonthsthetemperatureinmostofCanadausuallystaysbelow0℃.HoweverinsomepartsofCanadasuchassouthernBritishColumbiathetemperaturerarelygoesbelow0℃.Inmostareaswherepeoplelivesnowwillbeonthegroundfrommid﹣Decembertomid﹣March.ThoughCanada'swintermaybemuchcolderandlongerthanyouareusedtoitcanbeveryenjoyable.FormanyCanadiansbeingactiveinwinterisanimportantpartofenjoyinglife.Therearemanyoutdoorwinteractivitiesincludingskiingicefishingwalkingandskating.Joininginoneoftheseactivitiesmayhelpyouappreciatewinterandenjoyyourtimeoutsideinthesnow. Dressingforwinter DuringwinterinCanadayouwillneedwarmclothing.Ifpossiblearrivewiththeseitemsorbepreparedtobuythemsoonafteryourarrival.Youwillneed: ☆warmwaterproofboots☆ascarfforyourneck ☆ahatthatcoversyourears☆glovesforyourhands ☆thickwintercoatspantsandsweaters Layerskeepyouwarm It'sagoodideatolayeryourclothingbyforexamplewearingaT﹣shirtandasweaterunderneathajacket.Ifyoubecometoohotit'salwayseasiertoremoveapieceofclothingthantoaddanother.OntheWestCoastpreparetodressforcoolrainyorsnowyweather.Youwillneed: ☆awarmwaterproofcoat☆waterproofhats ☆anumbrella☆rainbootsorsnowboots LearnmoreaboutweatherandseasonsacrossCanada.YoucanalsocontactRelatedLinksforexampleanimmigrant﹣servingorganizationinthecommunitywhereyouliveformoreinformationaboutdressingforwinter. 1Whatisthemainpurposeofthefirstparagraph? A.TotellaboutthedetailsaboutCanada. B.Toshowmanyoutdoorwinteractivities. C.TointroducethedailylifeofCanadians. D.ToencourageyoutoenjoywinterinCanada. 2IfyouspendawinterinCanadayou'llpreparethefollowingEXCEPT. A.anumbrellaandsunglasses B.thickwintercoatsandpants C.waterproofhatsandcoats D.snowbootsandgloves 3Inwhichpartofanewspapercanyoufindthispassage? A.Business. B.Sports. C.Tourism. D.Health.
鲁米诺又名发光氨是一种在犯罪现场检验肉眼无法观察到的血液可以显现出极微量的血迹形态的重要刑侦用有机物．有机物B是一种常用工业原料俗称苯酐以其为原料可以合成酚酞鲁米诺等物质．有机化合物C的苯环上有三个相邻的基团． 已知① ② 请回答以下问题 1关于酚酞的下列说法正确的是． A．酚酞的分子式为C20H14O4 B．酚酞遇FeCl3溶液显紫色 C．1mo1酚酞最多可与4molNaOH反应 D．酚酞中有三种官能团 2请写出下列化合物的结构简式有机物B鲁米诺． 3请写出C﹣D的方程式． 4有机物G的分子式为C9H8O4它是有机物A的最简单的同系物请写出符合下列要求的G的所有同分异构体的结构简式． a．含有羧基和酯基官能团b．苯环上有两个对位取代基 5设计以邻甲基苯甲酸为原料合成的流程图无机试剂任选．
短周期元素XYZMN位于元素周期表中五个不同的族且原子序数依次增大其中只有N为金属元素．X元素的原子形成的阴离子的核外电子排布与氦原子相同自然界中Y元素形成的化合物的种类最多．ZM在元素周期表中处于相邻位置它们的单质在常温下均为无色气体．下列说法错误的是
氢气作为清洁能源有着广泛的应用前景含硫天然气制备氢气的流程如下． 请回答下列问题 I．转化脱硫将天然气压入吸收塔30℃时在T．F菌作用下酸性环境中脱硫过程示意图如下． 1过程i的离子反应方程式为． 2已知 ①Fe3+在pH＝l.9时开始沉淀pH＝3.2时沉淀完全． ②30℃时在T．F菌作用下不同pH的FeSO4溶液中Fe2+的氧化速率如下表． 在转化脱硫中请在上表中选择最佳pH范围是＜pH＜这样选择的原因是． Ⅱ．蒸气转化在催化剂的作用下水蒸气将CH4氧化．结合下图回答问题． 3①该过程的热化学方程式是． ②比较压强P1和p2的大小关系P1P2选填“＞”“＜”或“＝”． ③在一定温度和一定压强下的体积可变的密闭容器中充入1molCH4和1mol的水蒸气充分反应达平衡后测得起始时混合气的密度是平衡时混合气密度的1.4倍若此时容器的体积为2L则该反应的平衡常数为结果保留2位有效数字． Ⅲ．CO变换500℃时CO进一步与水反应生成CO2和H2． Ⅳ．H2提纯将CO2和H2分离得到H2的过程如示意图 4吸收池中发生反应的离子方程式是．
全球碳计划组织GCPTheGlobalCarbonProject报告称2018年全球碳排故盆约371亿吨．达到历史新高． 1中科院设计了一种新型的多功能复合催化荆实现了CO2直接加氢制取高辛烷值汽油其过程如图甲所示． ①已知CO2g+H2g═COg+H2Og△H＝+41kJ•mol﹣1 2CO2g+6H2g═CH2＝CH2g+4H2Og△H＝﹣128kJ•mol﹣1 则上述过程中CO转化为CH2＝CH2的热化学方程式是． ②下列有关CO2转化为汽油的说法正确的是． A．该过程中CO2转化为汽油的转化率高达78% B．在Na﹣Fe3O4上发生的反应为CO2+H2＝CO+H2O C．中间产物Fe5C2的生成是实现CO2转化为汽油的关键 D．催化剂HZSM﹣5可以提高汽油中芳香烃的平衡产率 ③若在一容器中充入一定量的CO2和H2加入催化剂恰好完全反应且产物只生成C5以上的烷烃类物质和水．则起始时CO2和H2的物质的量之比不低于． 2研究表明．CO2和H2在一定条件下可以合成甲醇．反应方程式为 Ⅰ．CO2g+3H2g⇌CH3OHg+H2Og．一定条件下往2L恒容密闭容器中充入1.0mo1CO2和3.0molH2在不同催化剂作用下合成甲醇相同时间内CO2的转化率随温度变化如图乙所示． ①催化效果最佳的是催化剂填“A”“B”或“C“b点时v正v逆填“＞”“＜”或“＝”． ②已知容器内的起始压强为100kPa．若图乙中c点已达平衡状态则该沮度下反应的平衡常数Kp＝保留两位有效数字Kp为以分压表示的平衡常数分压＝总压x物质的量分数． ③在莱催化剂作用下CO2和H2除发生反应I外还发生反应Ⅱ．CO2g+H2g⇌COg+H2Og． 维持压强不变按固定初始投料比将CO2和H2按一定流速通过该催化剂发生上述反应ⅠⅡ经过相同时间测得如下实验数据 表中实验数据表明升高温度CO2的实际转化率提高而甲醇选择性降低其原因是．
向VmL0.1mol/L氨水中滴加等物质的量浓度的稀H2SO4测得混合溶液的温度和pOH[pOH＝﹣lgcOH﹣]随着加入稀硫酸的体积的变化如图所示实线为温度变化虚线为pOH变化下列说法不正确的是
BroadBand:byClaireL.Evans.Portfolio2018﹩27 Thoughoftenoutnumberedbymenwomenstayedintheboomingfieldofcomputing.InthisinspiringtalewriterEvansrecordsthecontributionsofsomeofthemanywomenwhoaidedtheriseofthemodernInternet. MemorablecharactersincludeElizabethJakeFeinleraninformationscientistwhohelpedresearchersnavigatetheArpaneandStacyHornwhostartedoneofthefirstsocialnetworksEcho. TheWizardandtheProphet:byCharlesC.Mann.Knopf2018﹩28.95 Thehumanpopulationismovingtoward10billion﹣﹣﹣someexpertsthinkwe'llnearlyhitthatmarkby2050.Howwilltheearthfeedhouseandotherwisesupportsuchacrowd?Environmentalthinkersusuallyfallintooneoftwocamps:thosewhopreferconservationandcontrollingconsumptionlikeWilliamVogtandthosewhotrustinnovationtosolveourproblemsNormanBorlaugforexample.WriterManncarefullyrecordsthelivesandthoughtofthefoundersofthesetwophilosophies. ALabofOne'sOwn:byPatriciaFara.OxfordUniversityPtess2018﹩24.95 InWorldWarImanywomenintheU.K.replacedtheirapronswithchemicalsuitsandsteppedintopreviouslymale﹣onlyfieldsofsciencewheretheyledwarresearchefforts.SciencehistorianFaraillustratesthelivesofmanyoftheseforgottenwomen.Althoughtheeramarkedamajorstepforwardforwomenscientistsmanyworkedforsmallwagesinanenvironmentofdiscrimination. Inthenearly100yearssincewomenhavecomealongwayFarawritesbuttheglassceilingsremainsolidandthepipelinesleaky. AtomLand:byJonButterworth.TheExperiment2018﹩19.95 Butterworthtakesreadersonanamusingjourneythroughtheunknownworldofparticle粒子physics.ThefirststopisAtomLandwhereButterworthexplainshowelectronsprotonsandneutronscometogethertobuildupeverythingweknow.Asthejourneyunfoldswelearnaboutlesser﹣knownparticles.Thankfullyourshipisequippedwithtoolssuchasmathematicalequations方程式andalaserlightthatlightsupthedarkestofconcepts. 1Whofocusesonthefutureofourearth? A.ClaireL.Evans. B.CharlesC.Mann. C.PatriciaFara. D.JonButterworth. 2Whichbookswillyouprobablyreadifyouareinterestedinwomen'scareer? A.BroadBand&AtomLand. B.TheWizardandtheProphet&AtomLand. C.BroadBand&ALabofOne'sOwn. D.ALabofOne'sOwn&AtomLand. 3What'sthepurposeofwritingthepassagesabove? A.Toclarifysomeconcepts. B.Tointroducesomefamouswriters. C.Tomakecommentsonsomebooks. D.Torecommendsomebooks.
已知 下列说法不正确的是
Asnowstormhitmyneighborhoodtheotherday.Ihadrecentlyagreedtobethehouse'sgroundskeeperwhichmeantIgot1withshoveling铲theinchesofsnowthatcoveredthedriveway. Ihadstayedinthehouseduringthe2soIwasactuallyprettyhappytohead3.IshoveledforanhourorsoandIfeltmusclesinmyarmsandlegsthatIhad4usedstarttoburn.BythetimeIfinishedshovelingIwasgettingthe5Inormallygetfrombiking.TobehonestIwaspretty6tostop. AfewdayslatersomefriendsandIgotintoa7abouthowharditistoexercise.Goingtogymsisbecomingthemostannoying8ever.Notexercisinghasaneffectonourhealth.Lessthan5%ofadultsarephysically9forhalfanhouraday.Notexercisingenoughcan10diseaseslikeheartdiseasescancerobesityanddepression. Andyetshovelingsnowwasthat11.Itdidn'ttaketoomuch12becauseIwasn'tshovelingforexercisebutto13thedriveway.Peoplepaymuchmoneyforgymmembershipsandclassesto14extrafat.Sowhynot15payingthefitnessindustrytoexerciseandhelpwitheachotherwithsuchkindof16?Surelythey'rebetteroff17thatmoneyandputtingtheenergytopracticaluse. AneighborhoodcouldhaveaFacebookgroupwherepeoplecould18thingstheyneededhelpwith.Thenpeoplewhowantedtoexercisecould19.Win﹣win.Insteadofmakingitabouthelpingpeopleitcanbeframedasanewfitness20. 1A.charged B.filled C.tasked D.crowded 2A.festival B.disaster C.rush D.storm 3A.outside B.inside C.forward D.backward 4A.usually B.directly C.really D.rarely 5A.challenge B.exercise C.threat D.power 6A.lucky B.angry C.happy D.sorry 7A.party B.meeting C.discussion D.fight 8A.homework B.routine C.solution D.business 9A.strong B.healthy C.active D.sleepy 10A.bringabout B.setoff C.takedown D.livethrough 11A.difficult B.easy C.valuable D.perfect 12A.determination B.intelligence C.reputation D.confidence 13A.design B.clear C.build D.wash 14A.puton B.passdown C.pickup D.burnoff 15A.enjoy B.miss C.stop D.escape 16A.reality B.labor C.dream D.faith 17A.saving B.collecting C.donating D.achieving 18A.seek B.imagine C.post D.examine 19A.helpout B.showoff C.turnaround D.runaway 20A.lesson B.skill C.map D.style
ClO2是一种优良的消毒剂浓度过高时易发生分解常将其制备成NaC1O2固体以便运翰和贮存．过氧化氢法制备NaC1O2的实验装置如图甲所示． 已知①2NaClO3+H2O2+H2SO4═2ClO2↑+O2↑+Na2SO4+2H2O． ②ClO2的熔点为一59℃沸点为11℃H2O2的沸点为150℃ ③当沮度低于38℃时NaClO2饱和溶液中析出的晶体是NaC1O2•3H2O．当温度在38﹣60℃时析出NaC1O2温度高于60℃时NaC1O2分解． 请回答下列问题 1当仪器组装完毕后有同学认为关闭弹簧夹K1和K2取下X上端的玻璃塞加入一定量的水后塞上玻璃塞再打开X下端的活塞可以检查装置的气密性．请判断该方法能否检查装置气密性并说明理由 2Cl﹣对ClO2的生成有一定催化作用．反应开始时在三颈烧瓶中加入少量盐酸ClO2的生成速率会大大提高并产生微量氯气．该过程经两步反应完成将其补充完整． ①用离子方程式表示 ②H2O2+Cl2═2C1﹣+O2+2H+． 3C中将装置浸入冰水浴中的作用是． 4若实验室采用如图乙所示的装置从C中的溶液中获得NaClO2晶体．则需要在该装置的Y处增加一个设备． ①采用上述装置浓缩NaClO2溶液的操作称为． ②水浴加热的温度最好控制在℃左右填序号． A.40B.55C.70D.100 ③装置中毛细玻璃管的作用是． ④当蒸馏烧瓶中出现大量晶体后填操作．用38﹣60℃热水洗涤晶体干操后得到产品． 5产品纯度的测定称取mg产品配成250mL溶液取25.00mol•L﹣1溶液加入足量的KI和稀H2SO4充分反应后加入指示剂用cmol•L﹣1Na2S2O3标准溶液滴定至终点I2+2S2O32﹣═2I﹣+S4O62﹣平均消耗标准溶液的体积为VmL则产品中NaClO2的质量分数是%．
假设你是李华得知你的英国好友Tom通过了来华支教的申请将于今年七月到边远地区教学.请根据下面的提示给他写封电子邮件: 1.表示祝贺; 2.分析可能遇到的挑战; 3.告知提前了解当地的风俗习惯. 注意: 1.词数100左右; 2.可以适当增加细节以使行文连贯.
下列有关说法正确的是
具有抗菌作用的白头翁素衍生物H的合成路线如图所示 已知 i．RCH2BrR﹣HC＝CH﹣R' ii． iii． 以上RR′R″代表氢烷基或芳基等 1A属于芳香烃其名称是． 2D的结构简式是． 3由F生成G的反应类型是． 4由E与I2在一定条件下反应生成F的化学方程式是此反应同时生成另外一个有机副产物且与F互为同分异构体此有机副产物的结构简式是． 5下列说法正确的是选填字母序号． A．G存在顺反异构体 B．由G生成H的反应是加成反应 C.1molG最多可以与1molH2发生加成反应 D.1molF或1molH与足量NaOH溶液反应均消耗2molNaOH 6以乙烯为起始原料结合已知信息选用必要的无机试剂合成写出合成路线用结构简式表示有机物用箭头表示转化关系箭头上注明试剂和反应条件．
著名的“侯氏制碱法”主要反应原理是NH3+CO2+H2O+NaCl═NaHCO3↓+NH4Cl．若实验室根据此原理制备少量的Na2CO3主要实验包括制取NH3和CO2→生成NaHCO3→分离NaHCO3→制取Na2CO3四个步骤．下列实验选用的主要仪器或主要步骤不正确的是
文中共有10处语言错误每句中最多有两处每处错误涉及一个单词的增加删除或修改. 增加:在缺词处加一个漏字符号∧并在其下面写出该加的词. 删除:把多余的词用斜线\划掉. 修改:在错的词下划一横线并在该词下面写出修改后的词. 注意:1.每处错误及其修改均仅限一词; 2.只允许修改10处多者从第11处起不计分. MyfriendLillyandIwereonthewaybacktohomefromschoolwhenwesawaboyfalloffhisbicycles.Theboylayonthegroundscreamedinpain.Werushedtohelpandfoundiftheboy'sleftlegwasbleeding.Ithappenedthatwehavelearnedsomeknowledgeaboutfirstaidbeforesoweknewhowweshoulddo.Wedialed120andcalledanambulance.WhilewaitingitItookoutmyhandkerchiefandpressedthemontothebleedingpoint.Thenwerolledtheboyontoonesidebutputhimintherecoveryposition.Westayedwithhimuntiltheambulancearrived5minuteslate.
AprojectinGambiaisempoweringwomenandreducingdangerouswasteatthesametime. TheWasteInnovationCenterfundedbytheEuropeanUnion'sGlobalClimateChangeAllianceshowswomenintheBrikamaareahowtorecyclewasteintousefulmaterialsandproductswhichtheycanthensellinlocalmarkets. Wood﹣likewasteisrecycledintocharcoal木炭forexamplewhichcanbeusedtosupersedefirewoodandreducethenumberoftreesthatarecutdownforfirewood.Foodwasteisrecycledintocompost混合肥料tofunctionasenvironmentallyfriendlyfertilizersandplasticisturnedintomanyusefulthings. SupportedbyWasteAidUKandtheGambiaWomen'sInitiativeGWIamongotherstheprojectprovideswomenwithskillstheycanusetobecomeself﹣sufficient自给自足的.Womenlearningatthecentercomefromfivecommunitiesandsomeofthemtravelasfaras12milestolearntheseimportantskillsthatwillprovidethemwithanincomeaccordingtoTheGuardian. IsatouCeesaywhonowleadstheGWIhighlightedtheneedtofocusoneconomicequalityinhercountrytellingTheGuardianIntermsofeducationwomenaretheoneswhoarealwaysbehind.Boysarechosentogotoschool.Whenweconductourtrainingwefindwomencandoalotbutdon'tknowwhotheyareorhowtoimplement实施things. AccordingtotheWorldHealthOrganization'sCountryCooperationStrategy2008﹣2013reportthemainenvironmentalissuefacingGambiaispoorwastemanagementinurbanareas. NdeySirengBakurinexecutivedirectoroftheNationalEnvironmentAgencyhasvoicedconcernoverhealthandenvironmentalriskssuchaswaterpollutiontheincreaseofinsectsaswellasfloodingthatoccurasaresultofpoorwastemanagement. 1WhatdoestheWasteInnovationCentertrytodo? A.DeveloplocalmarketsinBrikama. B.Teachwomenhowtoinventnewthings. C.Keepwomenawayfromdangerouswaste. D.HelpwomeninBrikamabenefitfromwaste. 2WhatdoestheunderlinedwordsupersedeinParagraph2probablymean? A.Replace. B.Transform. C.Burn. D.Reserve. 3FromwhatIsatouCeesaysaidwecanlearnthatwomeninGambia. A.don'tlearnnewthingsfast B.aren'tinterestedineducation C.reallyhopeforeconomicequality D.arenotfairlytreatedinthecountry 4Whatisthewriter'spurposeofwritingthelastparagraph? A.Tosummarizethepreviousparagraphs. B.Toprovidesomeadviceforthereaders. C.Toaddsomebackgroundinformation. D.Tointroduceanewtopicfordiscussion.
ItwasapainfultimeformeforIsufferedfromanillnessandmightneverbeabletohaveachild.Asmy40thbirthdayapproachedIbeganforthefirsttimetonoticebabiesandtheirhappysmilingmotherswhereverIwent. OnenightIcametoacafetokilltheboringtime.Anelegantlydressedsightlyolderwomanwasseatednexttome. Wouldyouliketoseeapictureofmydaughter?sheaskedmehandingmeaphotoofasmilingChinesegirl.ThechildwasaboutsevenyearsoldandwaswearingaSnowWhitecostume.That'sMelanienowinthefirstgradeshesaid.Icouldhearthemotherlyprideinhervoice.She'sprettyIsaid.Ilovehercostume.ThewomanexplainedthatshefeltstronglyaboutteachingherdaughteraboutChinesecustomsandmaintainingtiestohershoes.Whatmadeyoudecidetoadopther?Iasked.Ididn'twantworktobemywholelifeshesaid. I'mnotsureifshesawthetearsinmyeyesasIrepliedIdon'teitherbutI'mafraidit'stoolate.Iwas51whenIadoptedMelanieshesaid.Andit'sthemostrewardingexcitingthingI'veeverdone. WhenmyhusbandandIreturnedfromChinawithournine﹣month﹣olddaughterMadelineinNovember2017JillwasoneofthefirstpeopleIe﹣mailed.Ididit!Iwrote.I'mamotherandshe'sbeautiful Congratulationsshewroteback.WerecentlyreconnectedonFacebookandItoldherYouchangedmylife. 1WhatcanbeinferredfromParagraph1? A.Theauthorregrettedhermarryingtooearly. B.Theauthorwasrecoveringfromaseriousdisease. C.Theauthordidn'thaveachildofherownduetosomeillness D.Theauthorhadbeeneagertobeahappymotherforalongtime. 2WhichwordscanbestdescribeJillaccordingtoParagraph3? A.Elegantandgenerous. B.Caringandconsiderate C.Friendlyanddetermined. D.Practicalandindependent 3Whatcanwelearnabouttheauthorfromthetext? A.Shewouldn'tdevoteherwholelifesimplytowork. B.SheappreciatedthepicturedrawnbyMelanie C.Herhusbandwasagainstheradopting. D.HerdreamwaseventuallyrealizedinthecompanyofJill 4Whatintheauthor'spurposeinwritingthetext? A.Tostresstheinfluenceofthekindness B.Toshowusthehiddenbeautyinourworld C.Tocallonustoadoptmorehomelesschildren D.Tosharehermeaningfuladoptionstorywithus.
Doyoulikewritingafewparagraphseverydayaboutyourexperienceshopesmemoriesorfeelings?Ifyoudon'tit'stimetomakeachangenow.Writejustafewparagraphseverydayaboutyourexperienceshopesmemoriesandfeelingsandyouwillimmediatelybegintoexperiencebenefitstoyourpersonalgrowthandpotential. Youwillgraduallybecomebetteratexpressingyourself.1Howeverwhenyoubecomelazywithwordsyoufinditismoredifficulttodescribefeelingsshareexperiencesandmakeyourselfunderstood. 2Asyouwriteaboutmemoriesitislikeopeninganoldphotoalbum.Yourpenbeginstoexplorefeelingsanddetailsyouhaveforgottenanddreamsyouhaveleftbehind.Yousuddenlyrememberpeopleyouwouldliketocontactagain.Writingisanactivitythatavoidsdistraction使人分心的事longenoughforyoutoexplorethosewonderfulmomentsofthepast.Sometimestheyarefrightening3 Writingaboutdailyexperiencesandfeelingsprovidesarecordedhistorythatwillinfluencehowyoumakefuturedecisions4Theylearnedfromwhathadhappenedbefore.Yourhistoryisimportant.Don'tletitbeforgotten. Writingremindsyouofyourdreamsandkeepsyoumovingtowardthem.Itisameansofkeepingtrackofyourpurposeandthegoalsthatwillleadyoutoachievethem.5Itshowswhenyouhavebeendistractedandmayneedtogiveallyourattentionagaintoyourwriting. Writingalittleeverydaycouldprovidethematerialthatsomedaybecomesapublishedbook.WhenIwroteaboutmydepressionandmyfour﹣year﹣oldgranddaughterwhogotlostinthemountainsIneverdreameditwouldbeinabook. A.Youwillrememberthingslongforgotten. B.Writingkeepsyouenergeticandfullofimaginationallthetime. C.Sometimestheyarewonderfulandalmostalwaystheyarehelpful. D.Soonerorlateryouaresurelytobecomeagreatprofessionalwriter. E.Reviewingwhatyouhavewrittenisaperfectwaytoseeyourprogress. F.There'sareasonthatthegreatestleadersinhistorywerestudentsofhistory. G.Whenyouwritedailyyoucanalwaysbeamazedathowquicklyyourwritingskillsimprove.
如图所示某种透明材料制成的直角三棱镜ABC折射率n＝∠A＝在与BC边相距为d的位置放置一平行于BC边的竖直光屏现有一细光束射到棱镜AB面上的P点入射光线与AB面垂直线CP的夹角为iPB的长度为d试求 ①当i＝且光束从BC面出射时光屏上的亮斑与P点间的竖直距离 ②当光束不从BC面出射时i的正弦值应满足的条件．
硫酸四氨合铜晶体[CuNH34]SO4•H2O常用作杀虫剂媒染剂在碱性镀铜中也常用作电镀液的主要成分在工业上用途广泛．常温下该物质在空气中不稳定受热时易发生分解．某化学兴趣小组以Cu粉3mol/L的硫酸浓氨水10%NaOH溶液95%的乙醇溶液0.500mol/L稀盐酸0.500mol/L的NaOH溶液来合成硫酸四氨合铜晶体并测定其纯度． Ⅰ．CuSO4溶液的制备 ①称取4g铜粉在A仪器中灼烧10分钟并不断搅拌放置冷却． ②在蒸发皿中加入30mL3mol/L的硫酸将A中固体慢慢放入其中加热并不断搅拌． ③趁热过滤得蓝色溶液． 1A仪器的名称为． 2某同学在实验中有1.5g的铜粉剩余该同学将制得的CuSO4溶液倒入另一蒸发皿中加热浓缩至有晶膜出现冷却析出的晶体中含有白色粉末试解释其原因． Ⅱ．晶体的制备 将上述制备的CuSO4溶液按如图所示进行操作 3已知浅蓝色沉淀的成分为Cu2OH2SO4试写出生成此沉淀的离子反应方程式． 4析出晶体时采用加入乙醇的方法而不是浓缩结晶的原因是． Ⅲ．氨含量的测定 精确称取wg晶体加适量水溶解注入如图所示的三颈瓶中然后逐滴加入足量10%NaOH溶液通入水蒸气将样品液中的氨全部蒸出并用蒸馏水冲洗导管内壁用V1mL0.5mol/L的盐酸标准溶液完全吸收．取下接收瓶用0.5mol/LNaOH标准溶液滴定过剩的HCl选用甲基橙作指示剂到终点时消耗V2mLNaOH溶液． 5A装置中长玻璃管的作用样品中氨的质量分数的表达式． 6下列实验操作可能使氨含量测定结果偏高的原因是． A．滴定时未用NaOH标准溶液润洗滴定管． B．读数时滴定前平视滴定后俯视． C．滴定过程中选用酚酞作指示剂． D．取下接收瓶前未用蒸馏水冲洗插入接收瓶中的导管外壁．
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