如果由工质和环境组成的系统,只在系统内发生热量和质量交换关系,而与外界没有任何其他关系或影响时,该系统称为()。

A、孤立系统
B、开口系统
C、刚体系统
D、闭口系统
查看答案
正确答案:

A

答案解析:

A项,孤立系统是指与外界既无能量交换又无物质交换的系统;B项,开口系统是指与外界有物质交换的系统;C项,刚体系统与本题无关,属于力学的范畴;D项,闭口系统是指与外界无物质交换的系统。

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GriffithworkedforafirmthatspecializedineconomicdevelopmentinWashingtonD.C.becausesheneededmoneytopayforherdebt.

Thissupermarketdevelopedrapidlyunderhis_____.

A、administration
B、suggestion
C、approach
D、appearance

Passage3

Questions11to15arebasedonthefollowingpassage:

TheideaofaspecialdaytohonormotherswasfirstputforwardinAmericain1907.twoyearslaterawoman,Mrs.JohnBruceDodd,inthestateofWashingtonproposedasimilardaytohonortheheadofthefamily—thefather.Hermotherdiedwhenshewasveryyoung,andherfatherbroughtherup.Shelovedherfatherverymuch.

InresponsetoMrs.Dodd’sideathatsameyear—1909,thestategovernorofWashingtonproclaimed(宣布)thethirdSundayinJuneFather’sDay.TheideawasofficiallyapprovedbyPresidentWoodrowWilsonin1916.in1924,PresidentCalvinCoolidgerecommendednationalobservanceoftheoccasion“toestablishmoreintimate(亲密)relationsbetweenfathersandtheirchildren,andtoimpressuponfathersthefullmeasureoftheirobligations.”TheredorwhiteroseisrecognizedastheofficialFather’sDayflower.

Father’sDaytooklongertoestablishonanationalscalethanMother’sDay,butastheideagrainedpopularity,tradesmenandmanufacturersbegantoseethecommercialpossibilities.Theyencouragedsonsanddaughterstohonortheirfatherswithsmallthank-youpresents,suchasatieorpairofsocks,aswellasbysendinggreetingcards.

DuringtheSecondWorldWar,AmericanservicemenstationedinBritainbegantorequestFather’sDaygreetingcardstosendhome.ThisgeneratedaresponsewithBritishcardpublishers.ThoughatfirsttheBritishpublicwasslowtoacceptthisratherartificialday,it’snowwellcelebratedinBritainonthethirdSundayinJuneinmuchthesamewayasinAmerica.

Father’sDayseemstobemuchlessimportantasoccasionthantheMother’sDay.Notmanyofthechildrenoffertheirfatherssomepresents.ButtheAmericanfathersstillthinktheyaremuchbetterfatedthanthefathersofmanyothercountries,whohavenotevenadayfortheirsakeinnameonly.

11.WhendidFather’sDayofficiallybegintohavenationalpopularity?

A.1907B.1909C.1916D.1924

12.WhofirststartedtheideaofholdingtheFather’sDay?

A.Mrs.JohnBruceDoddB.Mrs.JohnBruce’sMother

C.ThegovernmentofWashington.D.Somebusinessmen.

13.WhatflowerwillbepopularonFather’sDay?

A.LilyB.WaterLilyC.RedroseorwhiteroseD.Sunflower.

14.Whichstatementistrue,aaccordingtothispassage?

A.IttookevenlongerforMother’sDaytogainnationalpopularity.

B.ThebusinessmenhelpedtomakeFather’sDaypopular.

C.Father’sDayisonlycelebratedinAmerica.

D.Father’sDayisonlyatrickofthebusinessmentomakemoney.

15.WhatwasthefirstreactionoftheBritishpublishingtowardsFather’sDay?

A.Theythoughthighlyofitandaccepteditatonce.

B.Theyjustaccepteditatoncewithoutanyhesitation.

C.Theyjustthoughtitajoke.

D.Theythoughtitwastooartificialandtookalongtimetoaccept.

人际关系的核心是

A、尊重
B、利益
C、创造
D、信任
E、发展

Recentresearchhasclaimedthatanexcessofpositiveionsintheaircanhaveanilleffectonpeople’sphysicalorpsychologicalhealth.Whatarepositiveions?Well,theairisfullofions,electricallychargedparticles,andgenerallythereisaroughbalancebetweenthepositiveandthenegativecharged.Butsometimesthisbalancebecomesdisturbedandalargerproportionofpositiveionsarefound.Thishappensnaturallybeforethunderstorm,earthquakeswhenwindssuchastheMistral,HamsinorSharavareblowingincertaincountries.Oritcanbecausedbyabuild-upofstaticelectricityindoorsfromcarpetsorclothingmadeofman-madefibres,orfromTVsets,duplicatorsorcomputerdisplayscreens.

Whenalargenumberofpositiveionsarepresentintheairmanypeopleexperienceunpleasanteffectssuchasheadaches,fatigue,irritability,andsomesensitivepeoplesuffernauseaorevenmentaldisturbance.Animalsarealsoaffected,particularlybeforeearthquakes,snakeshavebeenobservedtocomeoutofhibernation,ratstofleefromtheirburrows,dogshowlandcatsjumpaboutunaccountably.ThishasledtheUSGeographicalSurveytofundanetworkofvolunteerstowatchanimalsinanefforttoforeseesuchdisastersbeforetheyhitvulnerableareassuchasCalifornia.

Conversely,whenlargenumbersofnegativeionsarepresent,thenpeoplehaveafeelingofwell-being.Naturalconditionsthatproducetheselargeamountsarenearthesea,closetowaterfallsorfountains,orinanyplacewherewaterissprayed,orformsaspray.Thisprobablyaccountsforthebeneficialeffectofaholidaybythesea,orinthemountainswithtumblingstreamsorwaterfalls.

Toincreasethesupplyofnegativeionsindoors,somescientistsrecommendtheuseofionisers:smallportablemachines,whichgeneratenegativeions.Theyclaimthationisersnotonlycleanandrefreshtheairbutalsoimprovethehealthofpeoplesensitivetoexcesspositiveions.Ofcourse,therearethedetractors,otherscientists,whodismisssuchclaimsandareskepticalaboutnegative/positiveionresearch.Thereforepeoplecanonlymakeuptheirownmindsbyobservingtheeffectsonthemselves,oronothers,ofanegativerichorpoorenvironment.Afterallitisdebatablewhetherdependingonseismicreadingstoanticipateearthquakesismoreeffectivethanwatchingthecat.

1.Whateffectdoesexceedingpositiveionizationhaveonsomepeople?

A.Theythinktheyareinsane.

B.Theyfeelratherbad-temperedandshort-fussed.

C.Theybecomeviolentlysick.

D.Theyaretootiredtodoanything.

2.Inaccordancewiththepassage,staticelectricitycanbecausedby___.

A.usinghome-madeelectricalgoods.

B.wearingclothesmadeofnaturalmaterials.

C.walkingonartificialfloorcoverings.

D.copyingTVprogramsonacomputer.

3.Ahighnegativeioncountislikelytobefound___.

A.nearapoundwithawaterpump.

B.closetoaslow-flowingriver.

C.highinsomebarrenmountains.

D.byarotatingwatersprinkler.

4.Whatkindofmachinecangeneratenegativeionsindoors?

A.Ionisers.

B.Air-conditioners.

C.Exhaust-fans

D.Vacuumpumps.

5.Somescientistsbelievethat___.

A.watchinganimalstoanticipateearthquakesismoreeffectivethandependingonseismography.

B.theunusualbehaviorofanimalscannotbetrusted.

C.neitherwatchingnorusingseismographsisreliable.

D.earthquake

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