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1.
INTRODUCTIONThcstcmfonl1ofnaturalKorcanpincforcst.ot\ingtothcsupprcsscdandshadcd,isvcry'difTcrcntt`iththatofplantation.Itis\'cry't'aluabIctostud}'thcstcmfonnforn1orcac-knot`lcdgcabouttl1ctrccd)-nan1icsofnaturalKorcanpinc.n1crcl1asbccnconsidcrabIcrescarchontl1cstc111for111cquationsasatoolforforcstmanagcmcnt,butitalmostbasnorclationshipt`-iththcbiologicalgrowthproccss.soitisx'ery'dimcuIttouscthccquationtoanalxrsisthcd\'amicsofstclllform.Hcrcthcdct'clopmcntofstcmformt"ascxPCctcdfornotonI\…  相似文献   

2.
在NaAc-HAc缓冲体系中研究竹炭对Ni(Ⅱ)的吸附规律.结果表明:介质pH、粒径大小、初始浓度、反应时间、反应温度对吸附存有影响,在298 K、pH =3.0、初始浓度C0=0.113 mg·mL-1、反应时间为24 h、竹炭粒径为0.2 ~0.4 mm等条件下,每克竹炭的静态饱和吸附量为55.57 mg;与一级动力学相比,竹炭的动态吸附过程更符合二级吸附动力学方程,吸附平衡时间为100 min;竹炭对Ni(Ⅱ)的吸附更好地符合Langmuir吸附等温线,竹炭粒径越小,吸附量越大.吸附热力学参数为:△H =8.19 kJ·mol-1,△S =78.12 J·mol-1K-1,△G298k=-15.08 kJ·mo1-1.此外,还采用红外光谱方法探讨了吸附前后相关化学官能团的变化.研究表明,竹炭可用于去除废水中Ni(Ⅱ)离子.  相似文献   

3.
Thenaturalbroad-leavcd/Koreanpineforestsn1ainl\'distributcdintvcstbankofJa-panScainnortheastAsia,rangingfromKorca,eastpartofnortl1castCl1il1atolittoralofRus-sia.ThctotaIarcaisabout5()()()()ok111=.Ap-proximatcIy'6()%ofitarcil1Cl1ina'3()%inRussiaandl()%inKorca.Tl1cKorcal1pincforestsoccurt`idclyineastcrnpartofnortl1-castChina,t`itl1l1ight'olulncandhighqualitywood.Sincelastccnmp',thcKoreanpinefor-estshavebccnextcnsivcl}'exploited.Thcin-tactnaturalold-gro'`1hforestsinChangbaiMountainsarcOnl…  相似文献   

4.
lntr0ducti0nTherearetivespeciesofswaninthew0rld.1'l1reeoftIlemwererecordedinCl1il1a.The}'arewhooperswal1(t:l:VnllsL:l;Vnlts).whistlingswal1(`:l;\'I1lIScohIn1hUIIIlIS)andInuteswan(`111q)1lls()l()r)lll.Amongthem.whooperswanis'themostthmousinChina.Because0ft…  相似文献   

5.
INTRoDUCTIoNInthispaper,wepresentatechniquckno\`-nas\\-a1'clcttransformwhichcanbcuscdloquantif}'spatialstrucforeasafunctionofscaIcandpositionalongoncdlmensiontran-sectWa\clctsx`creproposcdforseismicdatabxJMorlet.Therecent\'earshat'esccnas}'ntl1csisal11ongallthescdlffercntapproacl1cstllatl1asbccn\'crr'fcrtileforalltl1cficldscon-ccn1cd.Theu,a\'Clctofasignalc\'ol\1l1glntilllcdcpclldsontwo\'ariablcsfscalc(orfre-qucnc})andtlmc(posjtion).Wa\)cIcttransfor111lsintroducedasatecIlniquctoidentif}'…  相似文献   

6.
以含有单一的U(VI)、Pb(Ⅱ)溶液以及U(VI)和Pb(Ⅱ)混合溶液为吸附质,系统探讨了pH值、吸附剂量、吸附时间和初始离子浓度对向日葵秸秆吸附效果的影响。采用准一级动力学方程、准二级动力学方程、粒内扩散模型、Langmuir和Freundlich等温吸附方程对实验数据进行拟合,从分配系数和分离因子角度对吸附选择性进行分析,并对吸附机理进行探讨。结果表明:吸附20 mg/L的U(VI)-Pb(Ⅱ)溶液的最佳pH值为4.0、吸附剂量为2.0 g/L、吸附时间为720 min,U(VI)和Pb(Ⅱ)的去除率分别为77.55%、87.44%;U(VI)和Pb(Ⅱ)的吸附动力学在单离子和复配体系下均符合准二级动力学模型;吸附等温线均符合Langmuir等温吸附模型,单离子最大吸附量分别为327.0和67.59 mg/g,且当U(VI)高于200 mg/L时Pb(Ⅱ)的吸附过程也能用Freundlich模型描述。当离子初始浓度较低时向日葵秸秆对Pb(Ⅱ)具有更高的吸附选择性,而较高时则相反。向日葵秸秆吸附前后的SEM、EDX和FT-IR图谱表明,吸附U(VI)和Pb(Ⅱ)的主要方式为络合和离子交换。  相似文献   

7.
INTRoD[JCTIONTllcrcsearcI1OI1tl1ctI1c111opl1}'sIcalprop-crtiesofl1catandl11asstransfcrproccsscsi11``oodparticlcl11atcrlalsisratllcrlll11ltcdcur-rcntI}O11l}afct`papcrssofarasconccn1slllnybclbund(Slla11g.19(j()).Ho\tc\cr'tl1cullll,attol1a11dtI1cproductionof\"oodcl1ipa11dx`oodslla\lngctc.Asra\`matcrlals(Sl1ang*I()9l)forpulpandpapcr'paniclcboards'\\'oodfucl(Martalcna.l988)ort\'oodpaFticlc111atc-rialhascdcom6ositcproductsarcincrcasil1goxcrtllcx"orldTllccfficicnttechnolog1caIllandlil1gofth…  相似文献   

8.
lNTRODUCTlONThcdan1egcoftheforestratsisbecomingmorcal1dmoreserioustviththeincreaseoftI1cartificlaIforestinrccentvears.Theratscatsccds.}'oungseedIlngsandbarklnspringandxvintcr.t`l1ichcauscatyrgcnumberofsccd-lingsand}oungtrcestodie.Forthcsakeofthedct'cloplllclltofforestryandtl1cprotcctiol1oftllcrcscri'eforcstrcsourcc-thecontrolortl1cllarl11f[lIforcstratsappcarstobe\'cryi111por-tant.Cl1ch1icalcontrolisthcmostcfficicl1tmcthodthatiscas\'tobehandle.lou'cost.Itoccupicsa\'ery'lmportantpositio11i…  相似文献   

9.
Daxing'a11lingforcstregionislocatedintllcllorthcrnpart0fcoldten1peratczoncinChinacharctcri/cdbyl1arsl1climate,shortagcofacculnulatcdtcn1pcraturc,shortgrowingscas0n.Io\`s0iltel1lpcraturclncarly'sprlng'ctcThcmodclsforcultl\'atingsccdlingsarediffcrcntfrol11tI1oscinotherrcgions.lnordcrtoflndouttI1coptll11ul11l11odclsforcultl1atingsccdllngsofDahurlnlarcI1'oncof111alntimbcrtrccspcclcsinthlsrcglon.\"chadcarriedoutcxpcrilllcntlYo111l()89toI9()3andobtaincdtllcsllllplcbutpracticallncthodlbrdctcnnining…  相似文献   

10.
lntr0duction,4ruliaehIIa(Miq)see111isaIcaflosingSI11aIltree\\I1icl1beI0ngst0AraIiaceaeCl1inesAraIia.Itisoncki11doflnedicala11dcatablepla11ts.Tl1e.tcl1desl1ootil1earIysprillgisvaIuabIewiIdvegeIabIes-\vI1icl1c0l1lail1sricl1protei11,fat,restoredsugar-orgal1icacida11d111tICI1vi-tamin.Itis0neofInail1\viIdvcgetabIestbrexP()rt.However,thiswitdresoLlrceisco111i11gtobeexI1aIIsctcdbecaLlseofI1eaveygatI1eri11gforyears.Seedil1gal1dgrowillgseedlil1gexperi111cl1tof,,11-'Ili`IehII'Itvascotl11…  相似文献   

11.
Biodi`-crsit3t`asapopularrcscarcl1ingficldofmodernccologicalscicnccandcn"i-rom'lcntaI,.i....Ii].Biodivcrsit3rcscarcl1IcvcIhasbccndccPCrand`"erct'idcrsinccthcConfcrcnccofEn\'iron111cntandDc\'elop1992.DcscribingcOI11l11UI1it}'ccoIog}'`"ithfixcdquantitati\'ctccl1niqucsprol11ptcdstudyofcommunit3'ccology'.Litcraturcrcvict"softhccfTcctsofIbrcstmanagcmcntonbiodi\'crsity'u'crcfctvinCl1ina,butscicntistsfto1nthcotl1crcountricsl1adstud-icddccplytllccfTcctsofcachmanagcmcntintcnsityonbiodi\'crsit}'(…  相似文献   

12.
INTRODUCTIoNMongoIianoak(QItcI.cIISn1ongolica)extcnsi\'cl)'dlstributcsinDaxing-anli11g-Xiaoxing-anllng,Wandasl1an-Zl1angguangcail-ing.andl11oUI1tai11ousrcgiol1sofSl1a11jial1gPlainonhorizonIalscalca11d35I)-6()l)111abo`.cscalcvcIonaItitudcscalc.Itisoncof111ainaccol11pan}4ngtrccsPCcicsintl1czo11alforcsttypesinHcilonaiia11gProtincc.Thcstandsdominatcdb}'MongolianoakoccuP}'tIlcIarg-cstarcaintl1enaturaIsccondary'forcstrcgionsthatoriginalcdaftcrtl1cdcstructionof\'irgil1forcsts.Mongolia…  相似文献   

13.
GENERALCoNDlTloNABoUTCLI-MATECHANGEINHElLoNGJIANGPRoVINCEDtlrlngthepasscdll)()}ears(l88l-l`)8(j)ors().tllctcndenc}'ofmcanairtc111pcraturcincrcasct\ithfluctuationcl11ergcdin\ariousrcglonsofHcllonViangproxincc.Airtcmpcra-turcinl98()s-rcachcdtl1emaxil11un1uithinthcpasscdll)()y'cars.Thisphcl1ol11enonaccordcd``iththctcndenc}'ofglobalclil11ate\"ar1ni11g.Thel11eanairtc111peralurcil1tl1creccl1tl()}car(l()8()-l()8`))incrcascdb}l).6"Cascom-pal-cd\`ltl1tl1atll1tl1clbrl11er3())'carsacc…  相似文献   

14.
马建路  周彬  罗旭 《林业研究》1995,6(3):19-22
INTRoDUCTIoNThcdcscribingintcrsPCcificandintrasPCi-ficcompeitivcintcnsity'oftrccsPCcicsisal-``aysshortoftl1cdcsirablcquantitati\'cindiccsintraditionalPOpulationccqog}.Toprcdictgrott1hofindit-idualtrcccxactI}',sOI11crc-searchcrhateadt'anccd111a11}'quantitatit'cindiccsintcrPrcti11gcol11PCtiti\.cintcl1sit}'bc-twccnindividualtrccssincctI1cl96()'s.Tl1cscquantitatit'cindcxs}'stc111s.callcdasco111PCti-tionindcxs}'stc111salso'I1asbcc11considcrcdasanapproachtostal1dgro`vtl1prcdictionb)'grot'…  相似文献   

15.
熊文愈  黄樨 《林业研究》1997,8(2):77-82
IntroductionAsabranchofsystcn1scicnccs'ccos}'stc111scl1ginccr-ing,isdevelopcdfromtl1cpracticcofccoIogicalcl1gi-neeringforstudyandn1a11agcn1cl1tofecos}'Stcl11s.Itstheqandn1cthodolog}'arcl11ai11l}dcri\'cdfro111s}'s-temscnginceringands}'Stc11lsccoIog}'.II1tl…  相似文献   

16.
INTRODUCTIONAPOenZyl11evanahon(lsoZyl11evanahOI1),asoneof111oIecu1argel1ehcai111arkers.l1asbeenwidelyapplledtothefieldofgenehcs'pll}'slologyandsyste111aticaltaxono111yofpla11ta11danl111alsincel97O's,andalsoapplledtoful1gisnldies111orea11dl11ore111recentyears.Dlerearemal1y'el1Zy1l1esthatareisoZyl11es-alnongthe111Esterasel1asbeen111ore-wideIyappliedtothestudyofftl1Wrece11tly.Tl1estaini11gn1etl1odstoEstisocyl11earefew.a11donlyoneortwol11ethodswererecorded.T11eyarelnIhallyappIledtohlghe…  相似文献   

17.
AgcncrationrcfcrstoaIltrccsgencratcdinsamcPCriodoftimc.Tl1isisat`idcl}'ac-ccptedcol1ccpt.a11dtl1c111ostimPOrtantcharac-tcristicofgcncrationisgcncrationintcri'aloflime.TlcbiologicalcontcntisrcIati\'c1}'t'agucwhcnidcntif3'agcncrationonIyb}'mcansoftime.ltisPoi11tcdoutb}By31,lHlI(l985)tl1atagcncrationrcfcrstoalltl1ctrccst`11ichhax'csamcorigination,agc.morPho1og}',ccologica1proPCrt3'andPOsitionincom111unity,sotl1crcarcman}'`"a},stoidcntif3'gcncration.ltisjustbccauscofthcabundanccoftl1cconnota…  相似文献   

18.
INTRODUCTI0NScIllossManl1hcin1-t"hicl1isbclongtoRosaccacan`lRo.vol.'I1asbeautifulcolorandgoodt1oxtcrshapcltsflottcrlngpcrlod1sverylong(2~3mol1tl1s)SchlossMannhclmcanli"cundcrdiffcrcntcli1natcc0nditionsandcanbccultlX'atcdinpotandpla11tcdal0ngstrccts.Thctissueculturcn1ethod\"astlscdinthISstudy'f0rincrcasingpropagationratcofSclllossMannhcin1.MATERIALSANDMETHO0SExPcrimcntaIMatcriaIsScl1IossMa11nI1cll111\asscIcctcdIYon1grccnhousclnAugustof1`j()4Fulla11dunsproutll1gbudsxtcrctakc…  相似文献   

19.
DendlxilinIIisSIIPeIWlsbrokeoutil1theforestofDaxil1g'anMountainsregio111nl99O.Tlleligl1tandheatydal11agedareaisone111iI-llollhln=Tlledan1agedegreeofD.SItPeIwhlsnoteve11lntheregion.Thestandsdal11agedbyDendIxihnIIissIIPeIunlnsenous'i11ten11ediateandligl1tdegreeaPpearedaspatchshaPedis-tribuholl.Thereaso11thatthedifferentresu1tsaboveapPearedisstandenviro11l11e11tclearly.Therefor,undertl1eco11dihol1oflargeareaweatl1er.Itwasnotclearlythatwhichfactor1sllla1ninthestandenviroIUnent.n1eoccu…  相似文献   

20.
Withadvantagesofsimpleshape,conven-ientconstruction,lowbuildingdepthetC,pre-stressedconcreteV.Sisusedwidelyinbulld-ingbridge.Forevaluatequalityofdesignandconstruction,dead1oadtestinbuildingsiteoflenisconductedtoanalyzeanddeteforbearingcapaclty'anduseconditionofpre-strcssedconcreteV.S.However.accuratedateiscommonl\'influencedbvsuchconditionasonthesitecondition,increasingofdataerrorbytemPeratUreandhumidity,concretemateri-als,anditoftencostmorethantWodaystoprepareoneprcstrCssedconcreteV.Sonth…  相似文献   

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