学科分类
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8 个结果
  • 简介:Invarioustemperatures,theeffectsofinorganicacidsonthefreephenollevelinliquefactionproductswereinvestigated.Inthispaper,thefreephenollevelwasusedasanindicatortoevaluateliquefactionefficiency.Resultsshowedthatsulfuricacidwasthebestamongthe4acids.Undertheconditionofreactiontemperature150oC,reactiontime1.5h,liquefactionratio(liquid/particleboard)4andcontentofsulfuricacid6%,thefreephenollevelintheliquefactionproductsofwasteparticleboardis36.95%,andthatoforiginalparticleboardis24.27%.

  • 标签: 碎料板 液化 苯酚 无机酸 催化剂 效应
  • 简介:TheinteractionbetweenricehostanditspathogenXanthomonasoryzaepv.oryzae(Xoo)atcellularlevelwasstudiedbyusingaresistantsomaclonalmutantHX-3anditssusceptabledonorMinghui63.AfterinoculationwithXoostrainZhe173(Chinesepathotype|\).theactivityofsuperoxidedismutase(SOD)andperoxidase(POD)inthecallusofMinghui63wasincreaseddramatically,andtheactiveoxygen(O2^-)wasproducedatahigherrate;Meanwhile,thecallusgrewslowlywiththereductionofproteincontent.ComparedtotheactivityofSODandPOD.theproductionrateofO2^-andthefreshweightinHX-3callusvariedlittleaftertheinoculation.ItcouldbeproposedthatthereweregreatdifferencesbetweentheresistanceofHX-3andMighui63atcellularlevel.TherewasnodifferencedetectedconcerningresistancetobacterialleafblightinHX-3betweentheplantandthecallus.

  • 标签: 水稻 白叶枯病 抗病性 体细胞突变种 HX-3品种 细胞水平
  • 简介:Canada'sborealforestrepresentsanimportantcontributoroftheworld'swoodsupplyindustry.However,maintainingorincreasingproductivityoftheborealforestmaybechallenginginareasdominatedbyforestedpeatlands.Moreover,sustainablemanagementoftheseforestsmustalsoconsiderotherimportantaspectsoftheforestecosystemsuchasbiodiversityandcarbonsequestration.Toaddresstheseconcerns,ecosystem-basedmanagementhasbeenimplementedinsomeCanadianjurisdictions,suchasinregionswherealargeportionoftheborealforestisdominatedbyforestedpeatlands.Theobjectivesofthispaperare(1)tosummarizeourcurrentunderstandingofhownaturaldisturbancesinfluencestanddynamicsandbiodiversityinforestedpeatlands,and(2)toreviewthemaindifferencesbetweennaturalandmanagedforeststandswithrespecttosoil.properties,standproductivity,understoryplantcommunities.Wealsodiscusshoweven-agemanagementregimesucceedsorfailstopreserveoldforestsandhowthislossaffectsbothforeststructureandhabitatdiversityatthelandscapelevel.Weconcludebyshowinghow,inborealforestedpeatlands,forestmanagementcouldcontributetocarbonsequestrationandmitigateprojectedclimatechange.

  • 标签: Clearcutting Fire Forest dynamics Partial cutting
  • 简介:Self-HelpDevelopment,SustainableManagementandUseofForestsandTreesattheLocalCommunityLevelTheForests,TreesandPeopleProgrammePh...

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  • 简介:Nonlinearmixedeffectsmodel(NLMEM)isbuiltontherelationshipofthefixedandrandomeffectsintheregressionfunction.TheNLMEMhasanobviouscomparativeadvantageinanalyzingthelongitudinaldata,repeatedmeasuresdataandmultileveldata.Two-levelNLMEMisusedtoanalyzethedominantheightforChinesefir(Cunninghamialanceolata).Theauthorsoutlinethetwo-levelNLMEMandintroducetheparametersestimationmethodofthemodel.BasedonfivecommonRichardandLogisticmodels,themixedmodelisbuilt.Themodelingdataareusedtocalculateandcomparewith19modelsderivedfromeachbasedmodel,and5optimalmixedmodelsarebuilt.Comparedthe5optimalmixedmodelswithtraditionalregressionmodels,itisshowedthatthetwo-levelNLMEMhasabetterfittingeffectthantheregressionmodel.

  • 标签: TWO-LEVEL nonlinear MIXED effects MODEL DOMINANT
  • 简介:Tocomparetheeffectsofslow-releasenitrogenfertilizeratsixdifferentlevelsontheflagleafchlorophyllfluorescencecharacteristicsofsuperhybridrice,afieldfertilizationexperimentwasconductedwithsuperhybridriceYLiangyou1asatestmaterial.Thephotosyntheticelectrontransportrate(ETR),effectivequantumyield(EQY),photochemicalquenchingcoefficient(qP),andnon-photochemicalquenchingcoefficient(NPQ)offlagleavesweremeasuredattheinitialheading,fullheading,10dafterfullheadingand20dafterfullheadingstages.ResultsshowedthatthevaluesofETR,EQYandqPincreasedwithricedevelopmentfrominitialheadingto20dafterfullheading,whereastheNPQdecreased.Duringthemeasuredstages,ETR,EQYandqPincreasedinitiallyandthendecreasedasnitrogenapplicationamountincreased,buttheypeakedatdifferentnitrogenfertilizerlevels.ThemaximumETRandEQYvaluesappearedatthetreatmentof135kg/hm2N.Inconclusion,theoptimumnitrogenamountforchlorophyllfluorescencecharacteristicsofsuperhybridricewas135180kg/hm2.

  • 标签: 叶绿素荧光特性 超级杂交稻 氮肥水平 旗叶 生育后期 电子传递速率
  • 简介:Basedonamultilevellinearmixedmodelapproach,anindividualdiameterincrementmodelwasdevelopedforfirplantationtreesgrowinginJiangxiProvince.Thedatasetusedinthisstudycamefromlong-termpermanentresearchplots.Thedatabaseconsistsoftotalof82counties,365plots,5416treesand16248observations.Thepaperchosemixedeffectsmodelsinsteadofregressionanalysisapproachbecauseitallowsforpropertreatmentoferrortermsandcorrelationinarepeatedmeasuresanalysisframework.Themodelwasdefinedasamixedlinearmodelwithparameterrandomeffectofplot,areaorplotandareasimultaneous.Inadditiontheheteroscedasticityandcorrelationwastakenintoaccount.Mixedmodelcalibrationofdiameterincrementwascarriedoutwiththeindependentdatausingadifferentsampleofcomplementaryobservations.Theresultshowedthatthetotalstandbasalarea,thediameteroftargettrees,theratioofbasalareaoflargertreestotargettreediameter,andaltitudewerefoundtobesignificantpredictors.Boththefittingmodelandthecalibratedmodelmeanasubstantialimprovementcomparedwiththeclassicalapproachwidelyusedinforestmanagement.Aftertakingintoaccountreasonablevariancefunctionofheteroscedasticityandcorrelation,themodelshowsbetterofgoodnessoffitthanonlytakingintoaccountparameterrandomeffects.Thistypeofmodelingmethodologyshowsflexible,preciseandaccurate.

  • 标签: INDIVIDUAL diameter INCREMENT HETEROSCEDASTICITY correlation structure
  • 简介:从一个螺丝钉出版社的米饭糠蛋糕或分泌物的外观对应于在抽取过程生产的油的水平。在操作背景,油抽取水平和蛋糕外观之间的关系被学习。蛋糕特征可靠地显示期望的油恢复抽取水平。这些结论适用于两Chainat1米饭糠和parboiled米饭糠。变量是螺丝钉出版社(在从8.5~19.8r/min的五个层次的集合)和在螺丝钉和桶(在1.0和1.9厘米之间的集合)之间的相应清理距离的速度。结果证明抽取的最大的层次为米饭糠是4.17%并且8.20%为parboiled米饭糠。在最大的抽取水平,仪器连续地解除了难的蛋糕,易碎,片状,在一个方面上晴朗、擦亮却在其它上迟钝、粗糙。

  • 标签: 螺旋压力机 操作设置 提取过程 米糠油 外观 采水