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1.
1.问题提出人们在检测视力时,都会辨识《标准对数视力表》.既然叫做‘对数视力表”,难道和对数有关系?如果和对数有关系,那么它的背后又有多少“数学内核”?仔细观察《标准对数视力表》就会发现,上面有14行每行不等个数的“E”形图标等距离自上而下排列,旁边标有两列数据,其中五分记录分别为规则的等差数列4.0,4.1,…,5.2,5.3,对应的小数记录却为不规则的数列0.1,0.12,0.15,0.2,0.25,0.3,0.4,0.5,0.6,0.8,1.0,1.2,1.5,2.0。为什么会有这样的设计?我国专门颁布了视力表的国家标准,它的意义究竟何在?  相似文献   

2.
Ⅰ.情景对话(5分)根据你所听到的句子,从A,B,C,D中选出最佳答语。1.A.Yes,please.B.Yes,Idloveto.C.No,Iwill.D.Yes,Ilikeit.2.A.Sure.Giveyou.B.Yes,justalittle,please.C.OK.Hereyouare.D.Thankyou.3.A.Imhappyyoulikeit.B.Imsorrytohearthat.C.Yes,Idloveto.D.Imsorry.4.A.Yes,Iwilldoit.B.Thankyou,Iwill.C.Itdoesntmatter.D.Oh,Imsorry.5.A.Thatsright.B.Thatsallright.C.Agoodidea.D.Idontknow.Ⅱ.对话理解(5分)根据你所听到的对话…  相似文献   

3.
广东、广西常见鸟类的疟原虫初步调查   总被引:1,自引:0,他引:1  
自1995年5月至1996年8月先后对广东、广西部分地区的常见鸟类的疟原虫进行了初步的调查,共检获鸟类26种,共367只.发现疟原虫6种,分别是三趾鹑疟原虫(P.(H).turnixsp.nov.),广西疟原虫(P.(N.)guangxiensesp.nov.),似联核疟原虫(P.(N.)parajuxtanucleare),残疟原虫(P.(H.)relictum),沃氏疟原虫(P.(N.)vaughani),还有一疟原虫为待定种(Plasmodiumsp.)对它们的红内期形态及红外期的寄生部位进行了研究.黄脚三趾鹑为国内外首次发现有疟原虫寄生,残疟原虫、沃氏疟原虫为广西新记录.  相似文献   

4.
Ⅰ.对话理解(10分)根据你所听到的对话及问题,从A,B,C,D中选出正确答案。1.A.Saturday.B.Friday.C.Sunday.D.Monday.2.A.Yes,theydo.B.No,theydont.C.Kategoesbybus.D.Idontknow.3.A.Yes,theywill.B.Yes,theyare.C.No,theywont.D.No,theyarent.4.A.Mabel.B.Dick.C.Tom.D.John.5.A.At7:10.B.At7:30.C.After7:00.D.Before7:00.6.A.Yes,shecan.B.No,shecant.C.Idontknow.D.Imnotsure.7.A.Yes,theywill.B.No,they…  相似文献   

5.
好心态秘诀     
《中学生博览》2012,(13):67-69
1.心里一定要充满阳光。2.时常保持感恩的心态。3.能者多劳,不要抱怨。4.不要吝啬微笑,适时赞美他人。5.人敬一尺,我敬一丈。6.做人做事无愧于心。7.不攀比,因为人比人,气死人。8.经常运动,运动可以忘记烦恼。9.知足常乐。10.不开心时,要释放出来。  相似文献   

6.
MrJohnsonwashavingtroublewithhisstomach,sohewenttoseeadoctor.Thedoctorexaminedhisstomachcarefully,buthecouldntfindanyproblem.Thenhesaid,“Well,MrJohnson,takeiteasy.Theresnothingserious.Stopsmokingandthenyoullbeallrightverysoon.”“Butdoctor,”answeredMrJohnson,“Ineversmoked.Idontlikesmokingatall.”“Oh,Isee,”saidthedoctor.“Thenstopdrinkingalcoholfromnowon.”“ButIdontlikeaclohol,”answeredMrJohnson.“Dontdrinkanyteaorcoffee,then,”thedoctorsaidtohim.“Idontdri…  相似文献   

7.
目的:建立用高效液相色谱法同时测定果脯佛手中甘草苷和甘草酸含量的方法.方法:采用LiChmspher RP—C18色谱柱,以乙腈-水(1.2%甲酸)为流动相,梯度洗脱,检测波长254nm.结果:甘草苷在0.21-3.15μg范围内呈良好的线性关系,回归方程为Y=1053.9644X-0.0528(r=0.9999),平均回收率为99.7%,RSD为1.72%(n=9),重复性RSD为0.14%;甘草酸铵在0.25—6.25μg范围内呈良好的线性关系,回归方程为Y=1311.3875X-14.3144(r=0.9998),平均回收率为100.8%,RSD为1.31%(n=9),重复性RSD为0.40%.结论:方法操作简便,结果可靠,重现性好.  相似文献   

8.
Ⅰ.根据句意,从A,B,C,D中选择一个正确答案,完成下列反意疑问句。1.Letsmeetatthestation,?A.willyouB.wontyouC.shallweD.shantwe2.LetusgototheSummerPalacethisafternoon,?A.willyouB.wontyouC.shallweD.shantwe3.Youhadyourlunchatschool,?A.hadyouB.hadntyouC.didyouD.didntyou4.Katehastoworkharderfromnowon,?A.hasshetoB.hasntsheC.doessheD.doesntshe5.Youseldomgotothemovies,?A.doyouB.dontyouC.willyouD.wontyou6.Fewpeoplewenttomeethimyesterday,?A.didthe…  相似文献   

9.
为研究螺旋藻的免疫调节及抗肿瘤作用的有效成份,增强药物作用效应,通过煮沸及高压,获得螺旋藻的耐热成份.将处理后的螺旋藻,皮下注射给腹腔荷小鼠肝癌细胞H22瘤株的荷瘤小鼠,同时设立生理盐水对照组.共给药4次,记录误组荷瘤小鼠成活天数.实验结束后,再重复一次本试验.实验结果表明:实验治疗组小鼠,平均成活天数,第一次实验及第二次实验分别为19天及18.9天,(P>0.05).对照组两次实验结果分别为15.8天和15.9天(P>0.05).说明实验稳定可靠.统计学处理表明,实验治疗组与对照组小鼠,存活天数有极显著差异P<0.01,提示螺旋藻的耐热成份,对肿瘤有一定的治疗作用.  相似文献   

10.
听力部分(20分)Ⅰ.情景反应(5分)根据你所听到的句子,从A,B,C,D中选出正确的答语。1.A.Yes,itis.B.Yes,itdoes.C.Yes,ithas.D.Yes,itwas.2.A.Heusesitfordrinkingwine.B.Heusesthemfordrinkingwine.C.Itisusedfordrinkingwine.D.Theyareusedfordrinkingwine.3.A.38,000kilometresaway.B.380,000kilometresaway.C.30,000kilometresaway.D.300,000kilometresaway.4.A.Oh,good.B.Illuseit.C.Illbuyit.D.Letmetry.5.A.Aweeklater.B.Fort…  相似文献   

11.
本文观察和分析了121只家兔主动脉弓的分支,共见到7种分支类型。各种类型的出现率分别为:A型11.57±2.85%,B型26.45±3.83%,C型53.72±4.41%,Ⅰ型1.65±1.07%,A_3V型3.31±1.37%,BV型1.65±1.07%,C_1V型1.65±1.07%。在惠州市市场购进的家兔其主动脉弓分支类型多数为C型,其次为B型和A型。统计结果表明,家兔主动脉弓分支类型在雌雄体之间无明显差异(P>0.05)。  相似文献   

12.
Ⅰ.单项选择1.ChinaisfamoustheGreatWallandalsooneofthelargestcountrieswiththelargestpopulation.A.as,forB.for,likeC.with,asD.for,as2.oftheplayersinthisteamfromShanghai.A.Twothird,isB.Twothirds,areC.Twothree,isD.Twothrees,are3.Theage  相似文献   

13.
Oneday,arichmansawSam.HesaidtoSam,“Ihearyouareaverycleverchildandnothingisdifficulttoyou.Canyoutellmewhyyouaresoclever?”Samansweredwithasmile,“Oh,Imnotclever,insteadyouaretoofoolish.”Therichmangotangry.Samsaid,“Pleasedontbeangry.IfyoudontbelievewhatIsaid,nowIaskyouaquestion.Ifyouhaveonegroupofducks,Igiveyouan-othergroup.Thenhowmanygroupsofducksdoyouhave?”“Well,thatstheeasiestquestionintheworld,”saidtherichman.“Oneandoneistwo.Anyoneknowstheanswer.Ihavetwog…  相似文献   

14.
一、多余介词1.“和……结婚”不能译为“marrywith...”,只能译为“marry...”。例如:Janemarriedafriendofherbrothers.2.“为……服务”不能译为“servefor...”,只能译为“serve...”。例如:Scienceservesthepeople.3.“向……致敬(致意)”不能译为“saluteto...”,只能译为“salute...”。例如:Everysoldiersalutedthekilledlittlehero.4.next,last,this,that,every,some,any,all引起的时间状语前面不用介词。yesterdayafternoon,tomorrowmorning等前面也不用介词。例如:SeeyounextMo…  相似文献   

15.
JackandBillyarebothsevenyearsold.Onedaytheywentouttosellpies(馅饼)together.Beforetheysetout,JacksmothertoldJack,“Youtaketwelvepies,andsellthemforfivecentseach.Youmustnteatthem,andyoumustntgiveanyofthemtoyourfriends.”BillysmothertoldBillythesamething.Thentheywentdowntownto-gether.Afterawholemorning,Billysoldonlyonepie.Billyfeltveryhungry,butheknewhecouldnteathispies.Whatshouldhedo?Hethoughtforamoment,thenhehadanidea.HetookhisfivecentsandboughtapiefromJackandateit.Ja…  相似文献   

16.
随身听     
HaveyoueverusedawalkmantolearnEnglish?Ifyouhave,pleasekeepitup.Ifyouhavent,Isuggestyoubuyoneandstarttouseitatonce.MywalkmanhasgivenmealotofhelpinEnglishstudy.Asweknow,earlymorningisthebesttimeofday.SoeverymorningIturnonmywalkmanandlistentoEnglishwords,drillsandtexts.Oneyearhaspassed.IvegotusedtolisteningtoEnglishinthemorning.AndIlikespeakingEnglishwhilelistening,whichhelpsmere-citetextsandnowIcandoiteasilyandquickly.Intheevening,afterfinishingotherhomework,Iturnonmywalk…  相似文献   

17.
Little Billy     
WhenBillywasverysmall,helovedpictures.Hismotheroftendrewforhimonpiecesofoldpaper.Shewasverybadatdrawing,butBillyenjoyedherpic-turesandalwayswantedmore.Then,whenhewasalittleolder.Billy'smothergavehimsomepencilsandadrawingbook,andhebegandrawingpictures,too,buttheywerenevergood.WhenBillywasfiveyearsold,hismothergavehimasmallblackboard,somepiecesofchalk,andaduster.Helikedthoseverymuch.Onedayhewastry-ingtodrawapictureofhisfatherontheblack-board.Hedrewlinesandrubbedthemout,d…  相似文献   

18.
AFTER GROWING UP     
MynameisRenliqun.Iwasbornin1987.Iamstudyingatanexperimentmiddleschool.Iamalreadysixteenyearsoldthisyear.Idecidetohelpmymotherdomorefarmworkandhousework.Ialsoplantostudyharderanddomorereadingthisyear.Infact,readingismyhobby.Ilikereadingondifferentsubjects.Thebooksgivemeknowledgeandalwaysmakemehappy.ThenIthought:whenIamnineteen,IwanttogotoafamousuniversitytostudyinBeijing.Thisway,Icanmakemycontributiontothe2008thOlympicGames.AfterIgrowup,Iwanttobecomeahistorian,be…  相似文献   

19.
1.单个人名作主语时,如:Mike,Joy,Jack,HanMeimei,LiLei等。Mikelookslikehisfa-ther.Joyisagoodgirl.2.人称代词第三人称单数作主语时,如:he,she,it。HeisanEnglishteacher.Itlookslikeaball.3.单个地名作主语,如:London,Beijing,HongKong等。Beijingisourcapital(首都).Londonisacity(城市).4.单数可数名词作主语,如:abook,anapple,aruler等。Adeskisnearthedoor.Theap-pleisred.5.不可数名词作主语,如:rice,milk等。Riceiswhite.Milkisgoodforchil-dren.6.指示代词this,tha…  相似文献   

20.
“Iloveyou,China!Iloveyou,China...”EverytimewhenIhearthesong,Ifeelveryexcited.Thesongmakesmethinkofmanythings.Chinaisthethirdlargestcountryintheworld,covering9,600,000squarekilometers.Therearemanyriversandmountainsinherterri-tory.Herpopulationisover1,200,000,000,thelargestintheworld.Shehas56nationalities.Theyarealllikebrothersandsisters.Theyliveinthebigfamilyhappily.Shehasalonghistoryofmorethan5,000years.Manynationalheroesandleadersliveinou…  相似文献   

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