简介：ＡｐｐｅｎｄｉｘＡ：Ｔｈｅｄｅｒｉｖａｔｉｏｎｏｆｅｑｕａｔｉｏｎ（４）ＩｎＦｏｕｒｉｅｒｄｏｍａｉｎ，ｄ２（ｘ）＝２ｘ２ｉｓｔｒａｎｓｆｏｒｍａｔｅｄｉｎｔｏｄ２（ｋｘ）＝－ｋ２ｘ（Ａ１）Ｗｈｅｎｅｑｕａｔｉｏｎ（３）ｉｓｎｕｍｅｒｉｃａｌｙｃ...

简介：地震预警是人类进行灾害防御的科学前沿领域。本文基于德温特创新索引数据库中关于地震预警技术的专利数据，采用TDA和TI两大专利情报分析工具，结合二者的优势功能，对地震预警技术领域的专利数据展开多角度的专利情报分析，包括专利国家与地区分布、专利权人分布、专利申请逐年变化趋势等专利基本情况分析和专利矩阵、专利地图分析，以期为该领域的科研人员、政府部门和相关企业提供信息支撑。

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简介：常规长排列非双曲动校正公式是在VTI介质中得到的,它不能满足任意空间取向TI（ATI）条件下的扩展.本文以VTI介质中非双曲动校正公式为基础,基于我们推导得出的ATI介质中精确四次时差系数解析解和NMO速度解析解,给出ATI介质中长排列优化的非双曲动校正公式.通过与各向异性射线追踪方法计算所得出的＂精确走时＂结果对比,研究表明优化后的非双曲动校正公式能精确地描述任意强弱、ATI介质中随测线方位变化的走时曲线,可以用来替代耗时、多偏移距、多方位的射线追踪方法正演拟合ATI介质中长偏移距反射走时,为利用非双曲时距的各向异性参数反演提供理论基础性认识。

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简介：根据复数道分析进行了4D匹配和4D去噪，消除了剩余差异，改善了一致性，提高了4D结果的分辨率。文章介绍了该方法的相关原理和实施步骤，实例证明了该方法的有效性。

简介：Fifty-sevenstations(48gridstationsandninestratifiedstations)weresampledacrossthestudyregion(67.000°–88.394°N,152.500°–178.643°W)duringthe4thChineseNationalArcticResearchExpedition(CHINARE4)fromJulytoAugust2010bytheicebreakerR/VXuelong.Atotalof24speciesofHydromedusaewereidentifiedfrom130zooplanktonsamples,ofwhichsevenspeciesbelongedtoAutomedusa,eightspeciestoAnthomedusae,fourspeciestoLeptomedudae,andthreespeciestoSiphonophora.CatablemamulticirratumKishinouye,1910,BougainvilliabitentaculataUchida,1925,andEuphysajaponica(Maas,1909)wererecordedforthefirsttimeintheArcticsea.Inthepresentpaper,18speciesofHydromedusaeweredescribedandillustrated,ofwhichthreespeciesweredescribedforthefirsttimeintheArcticsea,and15speciesweredescribedforthefirsttimeinChina.

简介：人类生存的地球已有49亿年历史，记录地质年代的全球地层年表，如同年、月、日一样，依次分为宙、代、系、统、阶5个不同层次。为了在全球范围内进行地球演化时代对比，需要选择一些典型的地层剖面和位置点作为划分全球各时代地层的统一标准，国际上通常将其称为“金钉子”。它的确立是地层学研究的一项极高科学荣誉。

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简介：选取三江平原典型沼泽湿地——毛苔草沼泽，通过人工施加氮肥和磷肥来模拟农田污水排入沼泽湿地后，沼泽植物对污水的净化效果。从植物营养吸收角度进行野外实地污水净化模拟研究，对植物直接吸收利用的营养成分NH4^+-N、PO4^3--P进行了测试分析。研究表明毛苔草沼泽对水中的NH4^+-N、PO4^3--P的净化随时间的推移呈现明显的指数衰减下降趋势，随着氮、磷含量的增加，沼泽湿地对污水净化逐渐变慢，净化所需时间增长，曲线数值方程模拟效果较好。

简介：中国人民银行货币政策委员会秘书长易纲指出。我国物价下降的原因有4点：①整个市场供过于求。在国家经贸委调查的600种市场商品中，86％的商品供过于求，供求平衡的只占13．7％。

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：Therehavebeen12possiblelocationsoftheearthquakesoccurringintheSouthYellowSeasince1505.Inthispaper,thelocationoftheearthquakethatoccurredin1505hasbeendeterminedbythecollectionofmorehistoricaldataoftheinfluencedfield,referringtheisoseismaldataofearthquakeswiththeepicentralintensityⅨandcombininggeophysicalfielddatawithtectoniccondition,duetoitsgreatinfluenceonseismicsafetyassessmentofsomesignificantengineering.

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简介：At12:07UT(8:07pmChinaStandardTime)on2017Oct4,abrightbolidewaswidelyobservedintheShangri-LaregionoftheProvinceofYunnan,China(Figure1).TheeventwaswellobservedbythegeneralpublicasittookplaceonthenightoftheMidAutumnFestival,whichisassociatedwithmoongazing.SonicboomsandgroundshakingwerereportedinanareaofaboutathousandsquarekilometersnorthwestofShangri-LaCity.DatafromU.S.governmentsensorssuggeststhattheimpactenergyoftheeventwasapproximately0.54ktTNTequivalent,withtheterminusofthebolidepositionedat28.1°N,99.4°E.ThisisthelargestobservedbolideeventoverlandsincethebolideeventthattookplaceinMauritaniaon2016Jun27(1.2kt).

简介：CH4emissionrateshavebeenmeasuredcontinuouslyfortheearlyriceof1988andlatericesof1987and1988duringentiregrowingseasonsinaricepaddyfieldinHangzhou,ZhejiangProvince,China,byusinganautomaticsamplingandanalyzingsystem.DuringmostpartsoftheseasonsCH4emissionratesshowedstrongdiurnalvariations.Bi-modepatternswiththehighestvalueintheafternoonandasecondpeakatmid-nightweregenerallyfoundfortheearlyrice,whilethehighestvalueswerealmostalwaysfoundinthenightforthelaterice.Bi-modepatternswithasecondpeakintheafternoonwerealsofoundduringthereproductivephaseofthelatericeplants.Thesediurnalvariationsmaybeexplainedbythediurnalvariationsofthesoiltemperatureandtheactivityofriceplants.Strongseasonalvariationswithonepeakinthetilleringstageandtwoduringthereproductivephaseofriceplantswereobservedforallthethreegrowingseasons.Theseasonalvariationsmaybeexplainedbytheactivityofriceplants,availabilityoforganicsubstratesinthesoil,andtheactivityofsoilbacteriarelatedtosoiltemperatures,FertilizationdidnotshowsignificanteffectsonthetotalseasonalCH4emissionsbutslightlychangedthepatternoftheseasonalvariationsoftheCH4emissionrates.Averagedoverthemeasuringperiodsand8spots,CH4emissionratesof7.8mgm-2h-1fortheearlyriceand28.6mgm-2h-1forthelatericewereobtained.Basedonthesemeasureddata,thetotalglobalemissionofCH4fromricepaddiesisestimatedtobeabout90Tg/yrrangingfrom70to110,accountingfor20%ofthetotalsourceofCH4.

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简介：Acomprehensivestrengthmonitoringsystemusedonafixedjacketplatformispresentedinthispaper.Thelong-termmonitoringofW-11-4Aplatformachieved.Structuralresponses(strainandacceleration)atselectedlocations,aswellasassociatedenvironmentalparameters,havebeenobtained.Theemphasisofthepaperisplacedonthesystemdesign,andtheinstrumentationandoperationmethodologyemployedinthemonitoringofthestructuralresponses.Theperformanceofthesystemandthecharacteristicresultsobtainedduringits13-monthoperationarealsosummarized.

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