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设向量=(x,1),=(4,2),且∥,则实数x的值是 .
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高二下学期数学《》真题及答案
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如图所示可在竖直平面内转动的平台上固定着一个内壁光滑的气缸气缸内有一导热活塞活塞底面与气缸底面平行一定量的气体做密封在气缸内.当平台倾角为37°时气缸内气体体积为V然后将平台顺时针缓慢转动直至水平该过程中可以认为气缸中气体温度与环境温度相同始终为T0平台转至水平时气缸内气体压强为大气压强p0的2倍.已知sin37°=0.6cos37°=0.8. i当平合处于水平位置时求气缸内气体的体积 i若平台转至水平后经过一段时间环境温度缓慢降至0.9T.大气压强p0保持不变该过程中气缸内气体放出0.38P0V的热量求该过程中气体内能的变化量△U.
BecauselikemostofyouIbegancollegeinmyteensbutthesecondyearIwasofferedmydreamjobatUniversalStudiossoIdroppedout. WellIleftcollegebecauseIknewexactlywhatIwantedtodoandsomeofyouknowtoo﹣butsomeofyoudon't.Ormaybeyouthoughtyouknewbutarenowquestioningthatchoice.Maybeyou'resittingtheretryingtofigureouthowtotellyourparentsthatyouwanttobeadoctorandnotacomedywriter. Itoldmyparentsifmymoviecareerdidn'tgowellI'dre﹣enroll.Itwentallright.ButeventuallyIreturnedforonebigreason. MostpeoplegotocollegeforaneducationandsomegofortheirparentsbutIwentformykids.I'mthefatherofsevenandIKeptinsistingontheimportanceofgoingtocollegebutIhadn'twalkedthewalk.SoinmyfiftiesIre﹣enrolledatCalState﹣LongBeachandIearnedmydegree. Wellwhatyouchoosetodonextiswhatwecallinthemoviesthe'character﹣definingmoment.' Lifeisonestronglongstringofcharacter﹣definingmoments.AndIwasluckythatat18IknewwhatIexactlywantedtodo.ButIdidn'tknowwhoIwas.HowcouldI?Andhowcouldanyofus?Becauseforthefirst25yearsofourliveswearetrainedtolistentovoicesthatarenotourown.Parentsandprofessorsfillourheadswithwisdomandinformationandthenemployersandmentors有经验的顾问taketheirplaceandexplainhowthisworldreallyworks. AndIwanttobeclearthatyourintuition直觉isdifferentfromyourconscience.Theyworktogetherbuthere'sthedistinctionYourconscienceshoutshere'swhatyoushoulddowhileyourintuitionwhispershere'swhatyoucoulddo.Listentothatvoicethattellsyouwhatyoucoulddo.Nothingwilldefineyourcharactermorethanthat. 29.Theauthorwenttocollegeinhisfiftiesinorderto. A.getaneducationaldegree B.goforhisparents C.givehidchildrenanexample D.earnagoodreputation 30.Accordingtotheauthor'sviewwhatshouldwemainlyfollowwhenwechooseourcareer? A.Ourparents'advice. B.Ourownintuition. C.Ourconscience. D.Ourteachers'advice 31.What'stherightorderoftheeventsinthespeech? ①Tookhisjob②Gotmarriedandhadchildren ③Graduatedfromcollege④Droppedoutofchildren A.④③①② B.④③②① C.④①②③ D.④②①③
Abusybraincanmeanahungrybody.Weoftenseekfoodafterfocusedmentalactivitylikepreparingforanexam.Researchersthinkthatheavyboutsofthinkingdrainenergyfromthebrainwhosecapacitytostorefuelisverylimited. Sothebrainsensingthatitmaysoonrequiremorecalories卡路里tokeepgoingapparentlystimulatesbodilyhungerandeventhoughtherehasbeenlittleinthewayofphysicalmovementbodilyhungerandeventhoughtherehasbeenlittleinthewayofphysicalmovementorcalorieconsumptionweeat.Thisprocessmaypartlyaccountfortheweightgainsocommonlyseenincollegestudents. ScientistsattheUniversityofAlabamaatBirminghamandanotherinstitutionrecentlyexperimentedwithexercisetocountersuchimmoderatelypost﹣﹣studyfoodconsumption. GaryHunteranexercisephysiologistatU.A.B.oversawthestudy.Hunternotesthattoughactivitybothincreasestheamountofbloodsugarandlactate乳酸盐﹣circulatinginthebloodandincreasesbloodflowtothehead.Becausethebrainusessugarandlactateasfuelresearcherswonderediftheincreasedflowoffuel﹣richbloodduringexercisecouldfeedanexhaustedbrainandreducetheurgetoovereat. Thirty﹣﹣eighthealthycollegestudentswereinvitedtoU.A.B.'sexerciselabtoreportwhattheirfavoritepizzawas.Atalaterdatethevolunteersreturnedandspent20minutesdealingwithselectionsfromcollegeandgraduate﹣﹣schoolentranceexams.Nexthalfthestudentssatquietlyfor15minutesbeforebeinggivenpizza.Therestofthevolunteersspentthose15minutesdoingintervalsonatreadmilltwominutesofhardrunningfollowedbyaboutoneminuteofwalkingrepeatedfivetimes.Huntersaysthatshouldstimulatethereleaseofsugarandlactateintothebloodstream.Thesestudentswerethenallowedtogorgeonpizzatoo.Butbyandlargetheydidnotovereat.Infactthenon﹣exercisershoweverconsumedabout100caloriesmore. Thestudyhaslimitationsofcourse.Weonlylookedatlunch.Huntersaystheresearchersdonotknowiftherunnersconsumedextracaloriesatdinner.TheyalsocannottellwhetherothertypesofexercisewouldhavethesameeffectasrunningalthoughHuntersaystheysuspectthatifanactivitycausessomeonetobreakintoasweatitshouldalsoincreasebloodsugarandlactatefeedingthebrainandweakeninghunger'scall. 63.Accordingtothepassagemaycausemanycollegestudentstoovereatandgainweight. A.alotofenergy﹣consumingmentalactivities B.numerousphysicalmovementsorcalorieburning C.failuretoresistthetemptationofdeliciousfood D.bodilyhungercausedbyphysicalgrowth 64.Theunderlinedwordcounterisclosestinmeaningto. A.stimulateB.maximizeC.balanceD.prevent 65.Whatcanbeinferredfromthepassage? A.Runningismorebeneficialthanwalking. B.Sweatinginexercisecanmakepeoplehungrier. C.Theamountofbloodsugarandlactatecanaffectpeople'sappetite. D.Whenthebrainfeelsexhaustedpeopletendtodoexerciseforrelaxation. 66.WhichofthefollowingstatementsisFALSE? A.Mentalactivitiescanmakepeoplefeelhungry. B.Physicalexercisecanmakepeoplerefreshedandstayhungry. C.Sugarandlactatecanhelpenergizeandrestorepeople'sbrain. D.It'suncertainwhattypesofexercisecaneffectivelyfeedthebrain.
Wecanhaveconflictswithourimportantpersonslikefriendsrelativesetc.Inaheated61argueweusuallyuserudewordstomadesurewegainanadvantage62theotherperson.Thenthewholesituationgoesbadly.Soweshouldmakesurethattherearenoruderemarksandthesituation63moveinapositivedirection. It'seasyforustothinkwe'rerightand64somethingisn'tworkingoutitmustbesomeoneelse'sfault. 65ifyouaimtosolveaconflictyoushouldshowsomerespectandallowtheotherpartytoexpress66they.UsingremarklikeIunderstandyourconcernonthiswouldmaketheotherfeelmoreappreciated. Sometimessomepeoplegettooexcitedandmanybehaveinthewrongway.Thiscancausea67badsituation.Actuallytheyshouldcontroltheiremotionsandkeepcalm.Thishasto68learnthroughswlf﹣control. Thetipsmentionedaboveareusefulformostsituations.Howeverwedon'truleoutthepossibilitythattherearesomepeople69alwayswanttocreatesomesortoftroubleforothers.70putinanefforttoresolveaconflictwiththemmayjustnotbeawiseidea.Thebestwaytodealwiththesepeopleistoforgetthem.
A.technologyB.contemporaryC.stretchedD.hiddenE.recognized F.discoveryG.updatedH.extensiveI.countlessJ.estimatedK.definition Mostofuslearnatprimaryschoolthattherearesevencontinentsbutthenextgenerationofkidsmaybeaddingonemoretothatlist. AccordingtoarecentpaperpublishedintheGeologicalSocietyofAmericanJournalbyagroupofresearchersZealandiaisanewcontinentthat's31beneaththeocean. Zealandiais32tobefivemillionsqkm.MostofthismassiveareaiscoveredbywaterbutitshighestmountainsalreadyhavetheirownnameNewZealand. ThesmallcountryistheonlypartofZealandiathatisn'tunderwaterbutthepaper'sauthorswantthehugelandmasstobe33worldwideasitsowncontinent. ThescientificvalueofclassifyingZealandiaasacontinentismuchmorethanjustanextranameonalisttheresearcherswroteintheirpaper. ScientistsdiscoveredZealandiaallthewaybackin1995thenstarted34researchontheareausingunderwaterandsatellitemapping35.AftercompletingtheirworktheywerefinallyabletowriteareportsuggestingthatZealandiabenamedacontinent. Butwhodecidesonwhatisacontinentandwhatisn't?Thereisinfactnoofficialorganizationthatdoes.Somecountries'schoolsteachthattherearesixorevenfivecontinents.Thischangesdependingonwhereintheworldschoolis. Duetotheir36asacontinuousexpanseoflandsomeclassifyEuropeandAsiaasthesamecontinent﹣﹣knownasEurasia.SchoolsinRussiaandpartsofEasternEuropeteachthis. AndtomakethingsevenmoreconfusingFranceandGreeceaswellasothercountriesclassifyNorthAmericaandSouthAmericaassimplyAmerica. Thisargumentoverhowlandisdefinedhaseven37intoouterspace.In2006theInternationalAstronomicalUnionIAUdecidedthatPlutowasnolongeraplanet76yearsafterits38in1930.Expertsarguedthatitnolongermettherequirementsneededtobecalledaplanetalongsidetheeightothersinoursolarsystem.Itwasthereforerenamedadwarfplanet矮行星meaningthat39booksmodelsandmuseumexhibitsallovertheworldhadtobe40. ButwilltheworldtakethesamenoticeofZealandia?Thebestwaytotellistokeepaneyeonourtextbooks.
Grandmaalwaysmadeyoufeelshehadbeenwaitingtoseeyouandaccompanyyoualldaybutnowthedaysweregone.Shewas41ofsufferingfromAlzheimer'sdiseasewhenIwasakid.Iwas42asallkidsaresoIdidn'tthink43aboutit. Inmyfamilymygrandmaistheglue44ustogether.Iremembergoingtomygrandparents'farmhouseeverymomentIcouldwhenIwasakidwhereIalwaysenjoyedher45.LittledidIknowthesewouldbethe46ofmychildhoodthatIwouldmissthemost. AsIgrewupI47mygrandmachanging.Atfirstitwas48littlethings.OnceagainIdidn'tthinkitwasserious.Icouldneverhaveguessed49itwouldprogresstransformingmygrandmaintosomeoneIcould50recognize. OnedaymyfatherandIwenttovisitmygrandparents.We51thetimetalkingforhours52.Thenwith53eyesstaringrightpastmemygrandmaaskedNowyou'regraduatingthisyeararen'tyou?IwasafreshmansoIwas54whyshewasaskingmeaboutgraduation. Ittookmyfatherlongto55aresponseYes.Shemaynotknowwheresheisbutshewillbetherenomatterwhathappens.Iheardthe56inhisvoice. 57atsixteenIhaveabetterunderstandingofAlzheimer'sdisease.Itgreatly58metoknowthatonedayGrandmawill59beabletolookatmeandsayThatismygranddaughter.Sodon'tforgetallyour60outthere.Inotherwordsrememberthosewhocan't. 41.A.reformed B.thought C.informed D.reminded 42.A.thoughtful B.selfish C.foolish D.careful 43.A.second B.twice C.highly D.greatly 44.A.holding B.taking C.carrying D.pushing 45.A.happiness B.praise C.company D.comfort 46.A.thoughts B.stories C.feelings D.memories 47.A.accepted B.noticed C.met D.heard 48.A.just B.also C.already D.yet 49.A.what B.why C.how D.when 50.A.rarely B.seldom C.little D.hardly 51.A.wasted B.killed C.spent D.spared 52.A.occasionally B.regularly C.usually D.continuously 53.A.empty B.bright C.open D.wide 54.A.frustrated B.confused C.embarrassed D.discouraged 55.A.comeup B.putup C.comeupwith D.putupwith 56.A.relief B.happiness C.kindness D.sadness 57.A.Therefore B.However C.Thus D.Indeed 58.A.surprises B.excites C.encourages D.upsets 59.A.anylonger B.anymore C.nomore D.nolonger 60.A.elders B.ancestors C.relatives D.family
WhenIwasinmythirdyearatuniversitymyroommateswereAmericanfootballerssoIdecidedtojointhem.Irememberseeingtheminfrontofmewearingpads防护垫andthinkingtheyweregoingtokillme.Igottackled阻截sohardthatIwasfrightened.ButthenIrealizeditwasjustphysicalcontact.I'vebeenaddictedsince. Thefundamentalaimofthegameistoscorebyrunningwiththeballintoorreceivingtheballinsidetheopposition'sendzone.Everyplayeronthefieldhasasetresponsibility.I'marunningback.MyjobisusingmyspeedstrengthandskilltocarrytheballandkeeprunninguntileitherIscoreorIgetputdown.Anditdoeshurt. I'vebrokentwofingersandhurtmyshoulderbuttheworstwaswhenItrappedtheligaments韧带inthebackofmyleg.Ihadtotakeayearout.Butnoneofthatputmeoff﹣allIcouldthinkwashowIwasgoingtocomebackstronger.BesidestrainingwiththeteamInowhavemygymroutinetogetfitterfasterandstronger. AlthoughpeoplethinkAmericanfootballisaggressivethere'smuchmoretoit.Everyteamhasitsownplaybookoutingeveryone'sroleindifferentscenes.Myplaybookwas73pageslong.Wordscan'tdescribehowitfeelswhenitallcomestogetheronthefield. Americanfootballhaschangedmylifeforthebetter.I'velearnedtimemanagementhowtotakeresponsibilityformyactionsandhowmuchItreasurebeingpartofateam.Withinthefourlinesofthefielditisphysical.Emotionsrunhigh.Ifyou'reontheopposingteamyouaremyenemy.Butoncethegameisdonewe'relikeabigfamily. 32.Theauthor'sbodypartswerehurtEXCEPT. A.hisarm B.hisshoulder C.hisleg D.hisfinger 33.Whatcanweinferfromthetext? A.Theauthorwasverydelightedwhenfirstplaying B.Theauthorhasbenefitedmorethansufferingfromthesport C.Theauthorbegantoplayatthebeginningofhisuniversitylife D.PlayingAmericanfootballisverypopularamonguniversitystudents 34.HowdoestheauthorfindhisplayingAmericanfootball? A.Relaxing B.Challenging C.Boring D.Rewarding 35.Thepassageismanlyabout. A.therulesofplayingAmericanfootball B.howpainfulitistoplaythesport C.howthesporthaschangedtheauthor'slife D.thereasonfortheauthorplayingAmericanfootball.
某型号多用电表欧姆档的电路原理图如图甲所示.微安表是欧姆表表头其满偏电流Ig=500μA内阻Rg=950Ω.电源电动势E=1.5V内阻r=1Ω.电阻箱R1和电阻箱R2的阻值调节范围均为0~9999Ω. 1甲图中的a端应与红或黑表笔连接. 2某同学将图甲中的ab端短接为使微安表满偏则应调节R1=Ω然后在ab端之间接入一电阻Rx后发现微安表半偏则接入的电阻阻值为Rx=Ω. 3如图乙所示该同学将微安表与电阻箱R2并联利用该电路图组装一个“×100倍率”的欧姆表要求欧姆表的表盘刻度示意图如图丙所示其中央刻度标“15”则该同学应调节R2=Ω用此欧姆表测量一个阻值约2000Ω的电阻测量前应调节R1=Ω.
氨基锂LiNH2是一种白色有光泽的结晶或粉末熔点是390℃沸点是430℃溶于冷水遇热水则强烈水解.在380~400℃时锂与氨气直接反应可制得LiNH2下面是实验室制备LiNH2时可能用到的装置图回答下列问题. 1仅从试剂性质角度分析下列各组试剂不宜用于实验室制备NH3的是填宇母. A.浓氨水CuOB.NH4Cl固体CaOH2固体 C.浓氨水D.NH4NO3固体NaOH固体 2用1中合适的试剂制取的NH3按气流方向自左向右则图中装置的连接顺序为填接口处宇母装置A的作用是. 3装置C中仪器的名称是盛装的试剂是.实验开始后向X中通入NH3与加热仪器X的先后顺序为. 4实验室还可用浓氨水与固体NaOH混合制备氨气但多次实验表明此方法收集到的NH3量总是比理论值低许多其最可能的原因是. 5氨基锂能与热水反应生成LiOH与一种气体请推测该气体的成分并用实验验证你的结论.
设NA为阿伏加德罗常数的值下列有关说法正确的是
如图a所示质量为M=1kg的木板静止在光滑水平面上质量为m=1kg的物块以初速度v0=2.0m/s滑上木板的左端物块与木板之间的动摩擦因数为μ=0.2在物块滑上木板的同时给木板施加一个水平向右的恒力F当恒力F取某一值时物块在木板上相对于木板滑动的路程为s给木板施加不同大小的恒力F得到﹣F的关系如图b所示当恒力F=0N时物块恰不会从木板的右端滑下.将物块视为质点最大静摩擦力等于滑动摩擦力重力加速度g取10m/s2试求 1求木板长度 2要使物块不从木板上滑下恒力F的范围 3图b中CD为直线求该段的﹣F的函数关系式.
Howdoyoupayforgoodsinashop?Perhapsyoulikethetruereliabilityofhardcash?Perhapsthefinancialflexibilityofacreditcardsuitsyoubetter? 36 Whateveryouuseourbodiesoureyesourfingerprintsevenourmerepresenceinthestore.37Amazonarehavingatrialonstoreswhichhavenocheckoutswheretechnologytrackstheitemsyou'vetakenfromtheshelvesanddeducts扣除thetotalfromyouraccountwhenyouleavetheshop. FrenchsupermarketMonoprixtakesadifferentpathyouchooseyourgroceriesandleavethemwithahumancashier.Youthenleavetheshopwhilethecashiersettlesyourbillchargesyouraccountandorganizesdeliverytoyourhome.38What'smorewearableitemssuchasringsbraceletsandkeychainswillcarrychipsthatallowshopperstorandomlyshopgoingbetweenthewebanapporinstore. 39Perhapssomethingtotallynewwilltakeoffthatchangesmoneyasweknow.OnesuchpossibilityisexploredinthemovieInTimewhichimaginesafuturesocietyinwhichmoneyistimeitselfwherepeopletradetheamountoftimetheyhavelefttolive.Orperhapswewouldgobacktothesimplerfinancialworldoftheoriginaleconomy.Inthiscaseweneedn'tusemoneywhiletrading.Itseemsasiftheimagesofsacksofgrainandherdsofsheepbeingexchangedinancienttimescamebacktolifewiththehelpofmoderntechnology.40Doyouthinkso? A.Alltheseshoppingmethodsareconvenientforcustomers. B.Buttheonlythingweknowforcertainisthatmoneywillkeepchanging. C.Whoknowswhatwillhappentomoneyinthefuture? D.Itiscertainthattradewilldisappearinthefuture. E.Orperhapsyoupreferthesimpleconvenienceofasmartphone? F.Thisnewdevelopmentmeanstheendoftheplasticcreditcard. G.Infactit'shappeningalready.
工业上利用N2和H2可以实现合成氨气而氨又可以进一步制备硝酸在工业上一般可进行连续生产.请回答下列有关问题 1已知N2g+O2g=2NOg△H=+180.5kJ•mol﹣1 N2g+3H2g⇌2NH3g△H=﹣92.4kJ•mol﹣1 2H2g+O2g=2H2Og△H=﹣483.6kJ•mol﹣1 写出氨气经催化氧化完全生成一氧化氮和水蒸气的热化学方程式为. 2在一定体积的密闭容器中进行如下化学反应N2g+3H2g⇌2NH3g其化学平衡常数K与温度t的关系如下表 完成下列问题 ①比较K1K2的大小K1K2填“>”“=”或“<” ②在同温同压下判断该反应达到化学平衡状态的依据是填序号 A.2vH2正=3vNH3逆B.2vN2正=vH2逆 C.容器内压强保持不变D.混合气体的密度保持不变 3硝酸工业的尾气NO可用于制备NH4NO3其工作原理如图. ①其阴极的电极反应式为. ②常温下1LpH=6的NH4NO3溶液中cNH3•H2O+cOH﹣=mol•L﹣1. 4工业上生产尿素的化学方程式为2NH3g+CO2g⇌CONH22s+H2Ol 在T℃体积为4L的密闭容器中通入6molNH3和3molCO2反应达到平衡时cNH3=0.5mol•L﹣1eCO2=0.25mol•L﹣1.若此时保持T℃和平衡时容器的压强不变再向体积可变的容器中充入3molNH3则此时反应的V正V逆填“>”“<”或“=”.再次平衡后平衡常数为. 5已知KspAgCl=1.8×10﹣10若向50mL0.09mo1•L﹣1的AgNO3溶液中加入50mL0.10mol•L﹣1的盐酸混合后溶液中的Ag+的浓度为mol•L﹣1.
假定你是李华上个月你从外教Mr.Brown那里借了一本海明威Hemingway的小说老人与海TheOldManandtheSea但不慎将书丢失.为此请你给Mr.Brown写一封道歉信.信的内容包括 1道歉 2说明丢失原因 3提出补救措施 注意 1词数100左右 2可适当增加细节以使行文连贯. DearMr.Brown I'mwritingthislettertomakeanapologytoyoufor.
某有机物F在自身免疫性疾病的治疗中有着重要的应用工业上以乙烯和芳香族化合物B为基本原料制备F的路线图如下已知1乙烯生成A的原子利用率为100%则X是填化学式F中含氧官能团的名称为.2E→F的反应类型为B的结构简式为若E的名称为咖啡酸则F的名称是.3写出D与NaOH溶液反应的化学方程式.4E有多种同分异构体符合下列条件的同分异构体有种其中核磁共振氢谱有6个峰的物质的结构简式为.①能发生水解反应银镜反应且1mol该物质最多可还原出4molAg②遇FeCl3溶液发生显色反应③分子中没有甲基且苯环上有2个取代基5以乙烯为基本原料设计合成路线合成2﹣丁烯酸写出合成路线其他试剂任选.
如图所示A和B为竖直放置的平行金属板在两极板间用绝缘线悬挂一带电小球.开始时开关S闭合且滑动变阻器的滑动触头P在a处此时绝缘线向右偏离竖直方向电源的内阻不能忽略则下列判断正确的是
Forthousandsofyearspeoplehavesailedacrosstheoceanstotradeexploreandtransportgoods.Howevernoteveryshiparrivesatitsportofdestination.Weatherwarnavigationmistakesandbadluckhavecausedmanyshipstosinktothebottomoftheocean.Theseshipwreckswhichareestimatedtonumbermorethanthreemillionhavelongfascinatedus.Inadditiontobeinghistoricallyimportanttheysometimescontaingreatriches.Historicalresearchisakeymotivatorforshipwreckhunters.Shipscarryingdocumentsandartifactcanteachusaboutancientcivilizationsandimportantevents.Forinstancein1997thePandorawhichsankin791wasdiscoveredoffthecoastofAustralia.Thefindingsfromtheshiphelpedusunderstandtheeventssurroundingthefamousmutiny暴动onanothership﹣﹣﹣﹣﹣theBounty.AnotherimportantdiscoveryofftheUScoastin1996iswidelybelievedtobetheQueenAnn'sRevengetheflagshipoftheprivateBlackbeard.Profitisanothermotiveforshipwreckexplorationascompaniesuseadvancedsonarrobotsandretrievalequipmenttofindtreasureships.OnesuchfirmisOdysseyMarineExploration.Thecompanyhasfoundhundredsofshipsincludingin2007aSpanishsailingshipcontaining500000silvercoins.Theshipwhichsank200yearsagointheAtlanticOceancarriedatreasureestimatedtobeworth$500million.SoonafterthediscoveryalonglegalbattleoverownershiprightstookplacebetweenthecompanyandtheSpanishgovernment.Caseslikethesearepartofanongoingdebateaboutprotectinghistoricallyimportantshipsfromtreasurehunters.
聚合硫酸铁PFS是水处理中重要的絮凝剂以废铁屑为原料制备PFS的具体工艺流程如下 下列说法错误的是
GoodChoice!ToVisitCanadain2017 Whetheryou´reanadventureseekercultureloverorjustoverallcurioustravelerthisyearCanadawillappealtoyouwiththeusualamountofhospitalityenthusiasmandpride. TocelebrateCanada´s150thbirthdaythegovernmentdepartmentisgivingpeoplethegiftofexperiencetheopportunitytovisitalltheDiscoveryPass.ThispreferentialtermwillbevalidformMay202017untilOctober222017.Thoughthereareplentyofsplendidsceneryforyoutotourherearetwositesyoucannotavoidvisiting. *CanadianRockyMountainParks InthisareaknowtotheworldastheCanadianRockyMountaintherearefivenationalparksBanffNationalPark.ThesespectacularsitesweredeclaredaUNESCOWordHeritageSiteunderthenameCanadianRockyMountainParks.Youcanenjoywatchingwildanimalsandtakingpartinoutdooractivitieslikemountainbikinghikingfishinginthesummeraswellasskiingsnowboardingsnowshoeingandsleddinginwinter. TheusualDiscoveryPasspriceforRockyMountainParks PerAdult$60 Perchildunder16free Ticketsareavailableeitheronlineorattheattraction *NiagaraFallsStatePark ExperiencethepowerofNiagarafallsclosewhenyouridetheworldfamousMaidoftheMistMoattourorstandendertheBridalVeilFallsintheCaveoftheWinds.Eventhoughtheparkisopen365daysayeartheopeningofourattractionsisbasedoniceconditionsintheNiagaraRiver.SothebesttourtimetovisitNiagaraFallsissummerwhenithasthemosttremendouspower.DoitallwithaNiagaraFallsDiscoveryPassandmakememoriesthatwilllastalifetime! TheusualDiscoveryPassPriceforNiagaraFalls Adultabove16yearsold$40 Child6﹣16yearsold$30 NiagaraFallsoffersFREEadmissiontoalltheattractionstochildrenunder5 BuyyourDiscoveryPassonlineorattheattractions 21.WhatgiftwillCanadiangovernmentgivetothetouristsin2017? A.FreeAdmissionsforallthefamousattractions. B.AfreeDiscoveryPassforeachluckytourist. C.OfferingtastyCanadianfoodforfree. D.VisitingthefamousCanadianattractionsathalfprice. 22.IfyouvisitRockyMountainParksinJulywhattouristactivityyoucannottakeparting? A.Hiking B.Fishing C.Dogsledding D.Watchingwildanimals 23.ThebestseasontovisitNiagaraFallsissummermainlybecause. A.youcanridetheMistBoat B.theparkisopenonlyinthisseason C.thereisiceintheriver D.theFallhasthemosttremendouspower 24.Howmuchwillacouplewithafive﹣year﹣oldsonspendatleastiftheyvisitbothtowattractions? A.$100 B.$200 C.$260 D.$300.
假定英语课上老师要求同桌之间交换修改作文请你修改你同桌写的以下作文.文中共有10处语言错误每句中最多有两处.错误仅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. Lilyisagoodfriendofme.SheisanexchangestudentfromAmericathathasbeenstudyinginChinaforoneandahalfmonth.InordertomakefulluseofhershortstayhereLilyworkshardly.BecauseshehadnotstudiedanyChinesebeforecomingsoshehasmuchtroublecommunicatingwiththelocalpeople.Shegotupearlyinthemorningtostudyafterclass.SheissoindependentwhilelivefarfromherfamilyandquitehelpfultoourChinese.HoweverbusysheisshewouldrathertakehertimehelpuswithourEnglish.
如图所示两根相距L=0.8m电阻不计的平行光滑金属导轨水平放置一端与阻值R=0.3Ω的电阻相连导轨x>0一侧存在沿x方向均匀增大的稳恒磁场其方向与导轨平面垂直变化率k=0.5T/mx=0处磁场的磁感应强度B0=0.5T一根质量m=0.2kg电阻r=0.1Ω的金属棒置于导轨上并与导轨垂直棒在外力作用下从x=0处以初速度v0=4m/s沿导轨向右运动运动过程中电阻消耗的功率不变则
Ifyouhaveeverhadacatorhavewatchedoneofthemanyfunnycatvideosonlineyou'llknowthatcatshaveamindoftheirown.Alotofthethingstheydoarehardtounderstand﹣﹣﹣theyliketoclimbuptallfurniturefitthemselvesinsmallspacesandattacksmallobjectsfornoreasonatall. Nowscientistshavemanagedtofigureoutwhatexactlyisgoingoninthebrainsofourlittlefriends.AccordingtoTonyBuffingtonaprofessoratOhioStateUniversityintheUScats'strangebehaviorlargelycomesfromtheirwayoflifebackinthewild.Catstodaystillhavemanyofthesameinstincts本能thatallowedthemtoliveinthewildformillionsofyears.hesaidinaTEDTalk.Tothemourhomesaretheirjungles. Inthewildcatsarehunters.Theirbodiesandgreatbalancingabilitiesallowthemtoclimbtohighspotstobetterlookattheenvironment.Eventhoughtheydon'thavetohuntanymoreinhumanhousestheystillkeeptheoldhabitofviewingthelivingroomfromforexamplethetopoftherefrigerator. Cats'huntinginstinctisalsowhatmakesthemattacksmallthingslikekeysandUSBdrives.Inthewildtheyhuntwhatevertheycangetandmostoftheanimalstheykillaresmall. Howevercatscanalsobeprey.Thisexplainswhytheyliketostayinsmallspaceslikedrawersorwashingmachines﹣﹣﹣theyarehidingortheythinktheyarehidingfrommoredangerousanimals.Thisisalsowhycatspreferacleanboxasmellyonecouldeasilyshowenemieswheretheyare. Knowinghowcats'mindsworkisnotonlyusefulforbetterunderstandingthem.Itmayalsohelpcats'ownerstobettermeetcats'needs.Forexampleownerscouldtrytomakeclimbingeasierforcatsbymovingtheirfurniturearound.Theycouldalsousefoodpuzzlestomakeeatingfeelmorelikehuntinginsteadofjustgivingfoodtothecats. 24.AccordingtoTonyBuffington. A.cats'strangebehaviorishardforpeopletounderstand B.catsaremoreusedtolivinginthewildthaninhumans'homes C.catsbehavestrangelymainlybecauseofsomeinstinctsinthewild D.cats'instinctsareashelpfultothemtodayastheyweremillionsofyearago 25.WhichofthefollowingstatementsisTRUEaccordingtothetext? A.Catsliketoclimbuphighbecausetheywanttohidefromdangerousanimals B.CatsattackkeysandUSBdrivesbecausetheyhaveahabitofhuntingsmallanimals C.Catsenjoystayinginsmallspacesbecausetheyusuallyliveinsmallcavesinthewild D.Cats'preferenceforacleanboxprobablyhassomethingtodowiththeirhuntinginstincts 26.TheunderlinedwordpreyinParagraph5probablymeans. A.ananimalthatistoolazy B.ananimalthatlikeshidinggames C.ananimalthatkeepsitselfclean D.ananimalthatishunted 27.Thisarticleismainlywrittento. A.explorethereasonsbehindcats'strangebehavior B.describecats'pastwildexperiencetoreaders C.tellcatownershowtomakelifeeasierforcats D.comparecats'behaviorinhumanhomeswiththatinthewild.
全钒液流电池充电时间短续航能力强被誉为“完美电池”工作原理如图1所示反应的离子方程式为VO2++V3++H2OVO2++V2++2H+.以此电池电解Na2SO3溶液电极材料为石墨可再生NaOH同时得到H2SO4其原理如图2所示.下列说法正确的是
如图甲所示轻弹簧竖直放置下端固定在水平地面上一质量为m的小球从离弹簧上端高h处由静止释放.某同学在研究小球落到弹簧上后继续向下运动到最低点的过程他以小球开始下落的位置为原点沿竖直向下方向建立坐标轴Ox做出小球所受弹力F大小随小球下落的位置坐标x的变化关系如图乙所示不计空气阻力重力加速度为g.以下判断正确的是
如图所示为一个透明介质做成的直角三角柱的微截面其中∠A=30°∠B=90°一细光束平行于AC边从AB边的O点入射到该介质经AB边折射后直接照射在BC边上为使光束能从BC边射出三角柱求该透明介质材料折射率的范围.
叠氮化钠NaN3固体易溶于水微溶于乙醇不溶于乙醚是汽车安全气囊中的主要成分能在发生碰撞的瞬间分解产生大量气体将气囊就鼓起. 已知①NaNH2+N2ONaN3+H2O. ②NaNH2能与水反应生成NaOH和NH3 实验室利用如下装置模拟工业级NaN3的制备. 请回答下列问题 实验Ⅰ制备NaN3 1装置C中盛放的药品为 2为了使反应均匀受热装置D处b容器应采取的加热方式为. 3实验开始时首先应加热通氨气其目的是. 4氨气与熔化的钠反应生成NaNH2的化学方程式为. 实验Ⅱ分离提纯 反应完全结束后取出装置D中的混合物进行以下操作得到NaN3固体. 5操作ⅳ采用乙醚洗涤的原因是答一项即可. 实验Ⅲ定量测定 实验室用滴定法测定叠氮化钠样品中NaN3的质量分数 ①将2.500g试样配成500mL溶液 ②取50.00L溶液置于锥形瓶中加入50.00mL0.1010m1•L﹣1NH42CeNO3溶液. ③充分反应后将溶液稍稀释向溶液中加入8.00mL浓硫酸滴人3滴邻菲啰啉指示液用0.0500mol•L﹣1NH42FeSO42标准溶液滴定过量的Ce4+消耗溶液体积为29.00mL.测定过程的反应方程式为2NH42CeNO36+2NaN3=4NH4NO3+2CeNO33+2NaNO3+3N2↑Ce4++Fe2+=Ce3++Fe3+. 6配制叠氮化钠溶液时除需用到烧杯玻璃棒量筒外还用到的玻璃仪器有. 7若其它读数正确滴定到终点后读取滴定管中NH42FeSO42标准溶液体积时俯视将导致所测定样品中叠氮化钠质量分数选填“偏大”“偏小”或“不变”. 8减样中NaN3的质量分数为保留四位有效数字.
如图所示圆弧轨道AB被竖直固定其下端点B的切线水平.现将可视为质点的质量为m=1kg的小球从A点由静止释放小球从B点冲出后最终打在右方的竖直墙上的C点未画出在C点的速度方向与水平方向夹角为37°已知B端与墙壁的水平距离为l=0.3m不计一切摩擦和阻力g=10m/s2则下列说法正确的是
许多含氮物质既是农作物生长的营养物质也是重要的物质. 1肼N2H4N2O4常用于航天火箭的发射.已知下列反应 ①N2g+O2g═2NOg△H=+180kJ•mol﹣1 ②2NOg+O2g⇌2NO2g△H=﹣112kJ•mol﹣1 ③2NO2g⇌N2O4g△H=﹣57kJ•mol﹣1 ④N2H4g+N2O4g═3N2g+4H2Og△H=﹣1136kJ•mol﹣1 则N2H4与O2反应生成氮气与水蒸气的热化学方程式为. 2一定温度下向某密闭容器中充入1molNO2发生反应2NO2g⇌N2O4g测得反应体系中气体体积分数与压强之间的关系如图所示 ①abc三点逆反应速率由大到小的顺序为.平衡时若保持压强温度不变再向体系中加入一定量的Ne则平衡移动填“正向”“逆向”或“不”. ②a点时NO2的转化率为用平衡分压代替平衡浓度也可求出平衡常数Kp则该温度下Kp=Pa﹣1. 3已知在一定温度下的可逆反应N2O4g⇌2NO2g中v正=k正cN2O4v逆=k逆c2NO2k正k逆只是温度的函数.若该温度下的平衡常数K=10则k正=k逆.升高温度k正增大的倍数填“大于”“小于”或“等于”k逆增大的倍数. 4氨气是合成众多含氮物质的原料利用H2﹣N2一生物燃料电池科学家以固氮酶为正极催化剂氢化酶为负极催化剂X交换膜为隔膜在室温条件下即实现了合成NH3的同时还获得电能.其工作原理图如下 则X膜为交换膜正极上的电极反应式为.
有机物F是一种应用广泛可食用的甜味剂俗称蛋白糖它的一种合成路线如图所示 已知①A能发生银镜反应 ② ③R﹣CNR﹣COOH 请回答下列问题 1D中官能团的名称为F的分子式为. 2A的名称为反应③的反应类型为. 3反应④的化学方程式为. 4反应⑤中的另一种生成物是水则X的结构简式为. 5D有多种同分异构体请写出一种符合下列条件的有机物的结构简式 ①苯环上有2个取代基 ②与D具有相同的官能团 ③核破共振氢谱为6组峰且峰面积比为222221 6丙烯酸是重要的有机合成原料及合成树脂单体请写出以CH3CHO为原料合成丙烯酸的合成路线其它试剂任选
Onewaypeoplearerespondingtofoodsafetyconcernsisbygrowingtheirownfood.Howevernoteveryonelivesonpropertywithenoughspaceforaprivateplot.Onesolutioniscommunitygardenswhichhavebecomepopularworldwidenumbering18000inNorthAmericaalone.Inadditiontoprovidinglow﹣costdeliciousfoodthesepublicspacesoffercitiesarangeofotherbenefits. Communitygardensarelocatedinatownorcityandtendedbylocalresidents.Oftenthelandisonavacantlotownedbythecity.Thesiteisdividedintomanageableplotswhichmaybetendedbyindividualsorbythegarden'smemberscollectively.Sincethelandisusuallypubliclyownedthecostforgardenerstoleaseitisminimal.InfactNewYorkCitywhichishometomorethan750communitygardenstendedbymorethan20000memberschargespeoplejust$1ayeartoleaseaplot.Othercostsinvolvesoiltoolsseedsfencingandsoon.Howeverbecausethey'resharedbymanypeopleindividualgardenerspayverylittle. Acommunitygardencanquicklypayoffintermsofdeliciousfruitsandvegetablesinadditiontobeautifulflowers.Excessproducecanbesoldforaprofitatfarmersmarkets.Butagarden'sbenefitdon'tstopthere.Theyalsobeautifycitiesfosterstrongrelationshipsamongresidentsandloweranarea'scrimerate.Award﹣winningspaceslikeLondon'sCulpeperCommunityGardenevenattracttourists.Beautifulandaffordablecommunitygardensareoftendescribedasoasesincrowdedcities. 56.Communitygardensaredesignedforthosewho. A.areconcernedaboutfoodsafety B.liveinahousewithaprivateplot C.can'taffordtobuyorganicfood D.don'thavetheirownproperty 57.NewYorkCity. A.isownedby20000individualgardeners B.chargesresidentsalottoleasetoolsandfencing C.containsmorethan750communitygardens D.istendedbyprofessionalgardenersandlocalresidents 58.What'sthebenefitofcommunitygardens? A.Peoplecanenjoysafeanddeliciousvegetablesandanimalmeat. B.Residentsaremorefamiliarandrelatedwitheachother. C.Theneighborhoodisbecomingsaferbutoflowertaste. D.Peoplecanmakesomeprofitsfromthevisitingtourists. 59.Theunderlinedwordoasesisclosestinmeaningto. A.culturalandartcenters B.popularplatformsforexchanges C.peacefulandsafelands D.commercialandprosperousplaces.
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