简介：Cytarabine(1-β-D-arabinofuranosylcytosine,Ara-C),isolatedfromaCaribbeanspongespeciesTethyacrypta,isthefirstantitumordrugfromamarineresource.In1980,theUSFoodandDrugAdministrationapprovedthisdrugforthetreatmentofdifferenttypesofleukemia.Thisdrughasashortplasmahalf-life,lowstability,limitedbioavailability,andseveresideeffects.Toimprovestabilityandbioavailability,wesynthesizedninenovelderivativesbyblockingthecytarabinemetabolicsitesandimprovinglipophilicity.ThecLogPvaluesofthenewlysynthesizedcompoundswerecalculated.Allthesynthesizedcompoundsweremorelipophilicthancytarabine,resultinginmembranepermeabilityandbioavailabilityimprovement.TheantitumoractivitiesagainstleukemiacelllineHL-60wereevaluatedbyusingtheMTTassay.ThebioassayresultsrevealedthattheIC50valuesofcompounds5,8and9were0.080,0.090and0.057μmolL-1,respectively,whichwassimilarwiththatofcytarabine(0.056μmolL-1).Incomparison,compound4withaphosphategroupatO5’wasinactive.Becausephosphoesterbondsareeasilyhydrolyzedbyalkalinephosphataseandarecommonlyusedinproducingprodrugstrategies,compound4mightalsobemetabolizedinvivoandgeneratecompound3orevencytarabinethroughamulti-stepreaction.Thus,compound4mightbeapromisingcompoundtobedevelopedasaprodrug.

简介：Euphausiapacificisanimportantsourceofnaturalastaxanthin.StudieswerecarriedouttoassesstheextractabilityofastaxanthinfromE.pacificusingsubcritical1,1,1,2-tetrafluoroethane(R134a).Toexaminetheeffectsofmultipleprocessvariablesontheextractionyield,astaxanthinwasextractedundervariousconditionsofpressure(30-150bar),temperature(303-343K),time(10-50min),flowrate(2-10gmin-1),moisturecontent(5.5%-63.61%),andparticlesize(0.25-0.109mm).Theresultsshowedthattheextractionyieldincreasedwithtemperature,pressure,timeandflowrate,butdecreasedwithmoisturecontentandparticlesize.Amaximumyieldof87.74%wasobtainedunderconditionsof100bar,333K,and30minwithaflowrateof6gmin-1andamoisturecontentof5.5%.Thesubstantialastaxanthinyieldobtainedunderlow-pressureconditionsdemonstratesthatsubcriticalR134aisagoodalternativetoCO2forextractionofastaxanthinfromE.pacific.

简介：TheeffectsofBacillussubtilis2-1fromtheintestineofhealthyseacucumberonthegrowth,digestiveenzymeactivitiesandintestinalmicrobiotaofjuvenileseacucumber(Apostichopusjaponicus)weredeterminedinthepresentstudy.SeacucumberwasfedwithSargassumthunbergiipowdersupplementedwithB.subtilis2-1atdifferentconcentrationsvaryingamong0(control),105,107,and109CFUg-1for8weeks.ResultsshowedthatthegrowthperformanceandintestinalamylaseandtrypsinactivitiesweresignificantlyincreasedbydietaryB.subtilis2-1at109CFUg?1(P<0.05).However,dietaryB.subtilis2-1hadnosignificantinfluenceonthelipaseactivityinseacucumber(P>0.05).Thepolymerasechainreactiondenaturinggradientgelelectrophoresisand16SrRNAgenesequencinganalysisindicatedthatdietaryB.subtilis2-1at105and107CFUg-1inhibitedmostoftheProteobacteriaincludingthoseingenusVibrio.DietaryB.subtilis2-1at109CFUg-1notonlydecreasedtheabundanceandspeciesofgenusVibrio,butalsoincreasedtheintensityofgeneraPsychrobacterandBacillus.AspecificdosageofdietaryB.subtilis2-1couldincreasethegrowthandmodulatetheintestinalmicrobiotaofseacucumber;thusitmightbeanovelprobioticforkeepingthehealthofseacucumber.

简介：Thegrowth,biochemicalcontentandbioaccumulationquantityof2,2’,4,4’-tetrabromodiphenylether(BDE-47)inSkeletonemacostatumwerestudiedunderdifferentN:Pratios(1,4,16,64and128).AllcellularbiochemicalcontentsofS.costatumpresenteddecreasingtrendovercultivationtime.Atearlystageofcultivation,thecellularprotein,carbohydrateandlipidinS.costatumpresentedhighervaluesintreatmentsofN:P=4and16.However,theywerelowerinthesetreatmentsatthelatestage,buthigherintreatmentsN:P=1and128.Similarly,BDE-47levelspercellofS.costatumwerehigherintreatmentsofN:P=4and16atearlystageofcultivation,whichwere3.8and3.7ng(106cells)-1,respectively.Atthemiddlestageofcultivation,theBDE-47levelperS.costatumcelllowered;anditfurtherreducedinthetreatmentsofN:P=4and16atthelatestagewiththevalues0.6and0.5ng(106cells)-1,respectively.However,itroseinN:P=128,reachingupto2.3ng(106cells)-1.ComparedwithBDE-47percell,BDE-47peralgalvolumeunderdifferentN:Pratiosdidnotpresentobviousdifference.ThequantityBDE-47accumulatedpercellofS.costatumwaspositivelycorrelatedwithprotein,carbohydrateandlipidpercell;meanwhile,theBDE-47pervolumehadapositivecorrelationwithbiochemicalcontentpervolume.ThevariationofbioaccumulationabilityofBDE-47inS.costatumcanbeexplainedbybiochemicalchangesduetoN:Pratios.

简介：TiO2filmswereformedonmetallictitaniumsubstratesbytheanodicoxidationmethodinH2SO4solutionunderthe80VD.C..PhasecomponentandmicrostructurewerecharacterizedbyX-raydiffraction(XRD)andscanningelectronmicroscopy(SEM).Watercontactanglesontitaniumoxidefilmsurfaceweremeasuredunderbothdarkandsunlightilluminationconditions.Corrosiontestswerecarriedoutinseawaterunderdifferentilluminationconditionsbyelectrochemistryimpedancespectrum(EIS)andpolarizationcurves.TheresultshowedthattheTiO2filmpreparedbytheanodicoxidationmethodwasanatasewithauniformstructureandwithoutobviousporesorcracksonitssurface.Theaveragewatercontactangleofthefilmwas116.4?indark,incontrasttoanangleof42.7?undertheUVilluminationfor2hours,whichdemonstratesgoodhydrophobicproperty.Theanti-corrosionbehavioroftheTiO2filmwasdecliningwiththeextendedimmersiontime.Underdarkconditions,however,thehydrophobicTiO2filmretardedthewaterinfiltratingintothesubstrate.Theimpedancechangedslowlyandthecorrosioncurrentdensitywas2ordersofmagnitudelowerthanthatwiththefilmilluminatedbysunlight.AllofthosementionedaboveindicatethattheTiO2filmpossessesmuchbetterperformanceunderdarkcondition,anditcanbeappliedasanengineeringmaterialunderdarkseawaterenvironment.

简介：为弥补测高数据在近海区域因为编辑准则被剔除而导致近海测量数据质量不高的缺点,利用5参数模型的两种形式和Ice-2模型对Jason-2卫星在中国南海部分海域的海洋回波波形进行了波形重跟踪的研究,并选择20个海洋回波波形,依据最小二乘原理进行计算、分析、对比,发现5参数模型的指数形式的结果和Ice-2模型结果非常接近.研究结果表明,在开阔的海域,对Jason-2波形进行3种方法波形重跟踪时,可以优先考虑Ice-2模型.波形重跟踪技术能够提高卫星测高数据利用率,为科学研究提供可靠的数据保障.

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简介：TheenvironmentalconditionsaroundthefirstoffshoreHZ21-1steelwellheadplatformintheSouthChinaSeaarecharacterizedbydeepwater,frequenttyphoons,roughwaves,highwatertemperature,severelycorrosiveseawater,andthickfoulingorganismattachments.Thedesignandeffectivenessofgalvanicanodeprotectionsystemarepresented,andseveralmethodsaredescribed,whicharethecalculationmethodoftheprotectivecurrentdensityconsideringthevariationofwaterdepth,themethodofdeterminingprotectionparametersconsideringvariousfactors,thearrangementofanodesbasedonpotentialdistributionandcurrentrequirementsatdifferentwaterdepths,andthemethodofanodeinstallation.Finallytheeffectoftheaccuracyofselectedcathodicprotectionparametersontheeconomicbenefitsofoffshoreprojectsisalsodiscussed..

简介：CarboncycleisconnectedwiththemostimportantenvironmentalissueofGlobalChange.Asoneofthemajorcarbonreservoirs,oceansplayanimportantpartinthecarboncycle.Inrecentyears,ironseemstogiveusagoodnewsthatoceanicironfertilizationcouldstimulatebiologicalproduc-tivityasCO2sinkofhuman-producedCO2.Oceanicironfertilizationexperimentshaveverifiedthataddingironintohighnutrientlowchlorophyll(HNLC)seawaterscanincreasephytoplanktonproductionandexportorganiccarbon,andhenceincreasecarbonsinkofanthropogenicCO2,toreduceglobalwarming.Insixtydays,theexportorganiccarboncouldreach10000timesforaddingironbymodelpredictionandinsituexperiment,I.e.TheatmosphericCO2uptakeandinorganiccarbondrawdowninupperseawatersalsohavethesamemagnitude.Therefore,oceanicironfertilizationisoneofthestrate-giesforincreasingcarbonsinkofanthropogenicCO2.Thepaperisfocusedontheironfertilization,es-peciallyinsituoceanironexperimentsinorderthatthefutureresearchismoreefficient.

简介：Astochastictwo-dimensionalFornasini-Marchesini'sModelⅡ(2-DFMMⅡ)withmultiplicativenoiseisgiven,andafilteringalgorithmforthismodel,whichisoptimalinthesenseoflinearminimum-variance,isdeveloped.Thestochastic2-DFMMⅡwithmultiplicativenoisecanbereducedtoa1-Dmodel,andtheproposedoptimalfilteringalgorithmforthestochastic2-DFMMⅡwithmultiplicativenoiseisobtainedbyusingthestateestimationtheoryof1-Dsystems.Anexampleisgiventoillustratethevalidityofthisalgorithm.

简介：Thispaperpresentsthedetaildesignconditions,designcriteriaandmethodsaswellasdesignconclusionsoftheprocess,structureandcorrosionoftheproductionflowlinesandhighpressurewaterinjectionlinesinBZ34-2/4oilfieldinBohaiBay.AtpresentthisdesignrepresentsthedesigncapabilityandlevelinthefieldofthesubmarinepipelineengineeringofChina.

简介：Inthisstudy,thecombinedactionsofwavesandtidalcurrentsinestuarineandcoastalareasareconsideredanda2Dmathematicalmodelforsedimenttransportbywavesandtidalcurrentshasbeenestablishedinorthogonalcurvilinearcoordinates.Non-equilibriumtransportequationsofsuspendedloadandbedloadareusedinthemodel.Theconceptofbackgroundconcentrationisintroduced,andtheformulaofsedimenttransportcapacityoftidalcurrentsfortheOujiangRiverestuaryisobtained.TheDouGuorenformulaisemployedforthesedimenttransportcapacityofwaves.SedimenttransportcapacityintheformofmudandtheintensityofbacksiltingarecalculatedbyuseofLuoZaosen'sformula.Thecalculatedtidalstagesareingoodagreementwiththefielddata,andthecalculatedvelocitiesandflowdirectionsof46verticallinesfor8crosssectionsarealsoingoodagreementwiththemeasureddata.Onsuchabasis,simulationsofbacksiltingafterexcavationofthewaterwaywithasandbarundercomplicatedboundaryconditionsinthenavigationchannelinducedbysuspendedload,bedloadandmudbywavesandtidalcurrentsarediscussed.

简介：一、概述SDH—13A型测深仪自1990年装备部队以来,由于无相应的配套检测仪表,所以在仪器修理和长期使用后,其移相精度和校准脉冲宽度无法实时检测和校准;同时该机无数字信号输出,因而不便于实现水深测量自动化。针对这种状况,我们研制了DC—1A型多功能数显接口。该型接口可作为SDH—13A型测深仪的水深显示器使用,亦可用作SDH—13A型测深仪的专用测试仪表,还可作为水深转换接口,以便将SDH—13A型测深仪与Falcon—Ⅳ型微波测距/定位仪或水深测量自动化装置连接起

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简介：TheHY-1AsatelliteisthefirstoceanicsatelliteofChina.Duringthewinterof2002～2003,thedataoftheHY-1AwereappliedtotheseaicemonitoringandforecastingfortheBohaiSeaofChinaforthefirsttime.TheseaiceretrievalsystemoftheHY-1Ahasbeenconstructed.Itreceives1Bdatafromthesatellite,outputsseaiceimagesandprovidesdigitalproductsoficeconcentration,icethicknessandiceedge,whichcanbeusedasimportantinformationforseaicemonitoringandtheinitialfieldsofthenumericseaiceforecastandasoneofthereferencedatafortheseaiceforecastingverification.Theseaiceretrievalsystemofthesatelliteisdescribed,includingitsprocesses,methodsandparameters.TheretrievingresultsandtheirapplicationtotheseaicemonitoringandforecastingfortheBohaiSeaarealsodiscussed.

简介：一个方便、有效的过程被tosylation和硅石胶化在这研究支持的随后的β-消除为酒精的变换开发到石蜡。有在在0℃的pyridine的p-toluenesulfonyl氯化物的白酒的处理负担得起在房间温度在dichloromethane或氯仿与硅石胶化经历β-消除的tosylates，产出有高生产率的石蜡。

简介：TheDiverGasRecoverySystem(DGRS)isanimportantaccessoryequipmentofthe300mSaturationDiveSystem.Thesystemfacilitatestherecyclingofthebreathinggasesfordivers,therefore,ithasgreateconomicbenefits.InApril1995,a300munmannedtestanda100mmannedtestontheHY2031DGRSwerecarriedoutsuccessively.Tenmonthslater,anothermannedtestontheHY2032DGRS

简介：AninvivofluorescencediscriminationtechniqueforphytoplanktonpopulationwasdevelopedbyusingWaveletpackettransform,clusteranalysisandnon-negativeleastsquares.Thetechniquewasusedtoanalyzewatersamplesfromdifferentsearegions.Forsimulativemixtures,whendominantspeciesaccountfor60%,70%,80%,90%atthedivisionlevel,thecorrectdiscriminationratios(CDRs)are83.0%,99.1%,99.7%and99.9%withtherelativecontentsof58.5%,68.4%,77.7%and86.3%,respectively;whenthealgaedominanceare60%,70%,80%,90%,100%atthegenuslevel,theCDRsare86.1%,94.9%,95.2%,96.8%and96.7%,respectively.Forlaboratorymixtures,theCDRsare88.1%and78.4%atthedivisionandgenuslevel,respectively.Forfieldsamples,theCDRswere91.7%and80%atthedivisionandgenuslevel,respectively(mesocosmexperiments),andtheCDRswere100%and66.7%atthedivisionandgenuslevel,respectively(JiaozhouBay).ThefluorometrictechniquewasusedtoestimatethephytoplanktoncommunitycompositionandrelativeabundanceofdifferentclassesfortheApril2010cruiseintheYellowSeawiththeresultsagreeingwiththoseinpublishedpapersbyotherauthors.

简介：虽然许多注意被给了描述波浪的模型，潮和沉积运输在足够的详细处理决定在床上的本地变化在深测术的一个相对详细的代表上铺平，远，更少的注意被给了在大得多的规模考虑这个问题的模型(例如象一条潮汐的扁平、潮汐的隧道那样的geomorphological元素的)。这聚集了或lumped模型趋于不表示这些过程详细，但是相当在兴趣的规模捕获行为。如此的模型用平衡集中的概念开发了的是聚集的规模在潮汐的盆和邻近的海岸(ASMITA)之间的词法相互作用。在这份报纸，我们提供一些新卓见进平衡，和是这条建模途径的关键部件的水平、垂直的交换的概念。在一份同伴报纸，我们总结被承担了扩大原来的模型概念的开发的一个范围，到说明概念的框架的灵活性和力量。然而，日益增多地增加详细在详细基于过程的模型和我们给某考虑到在二之间的边界的更多的方向感动模特儿。聚集模型规模的HighlightsThe概念被探索，ASMITA模型的基础详细被构画出在在快规模的基于过程的模型和在聚集的模型使用的水平交换使用了的分散之间的关系被探索提出合适的平衡关系的基础被解释其他的方法包括移流和分散检验。