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1.
I.ASurveyofNaturalConditionsKarakon1l1i-WestKul1l1l11Mtsissituatedi11thel1orthwesternpartoftheQinghai-Xizang(Tibetan)Plateau.Therearel1igl11llountains,deepandnarrowgorqe5.brondplateausandothercomplicatedlandforms.Characteristicsoflal1dfor1115nreaccountablefortl1eforl11atio11ofvario[1sverticaldistributiol1ofsoilspectrun1.1nthisrcgiol1,theclimatcisf;lgidaiidd1:Yi4it1ilitt1eprecipitatioi1.Gc,,c,d11,.pl'ecipitatio11i11plainareaatfootofthemountainsislessthanlOOmmbutitchangesalongwttl1variatio… 相似文献
2.
1 All islands are measured by Plauimeter.2 Maps and charts used: a, British Admiralty Charts b, Charts published by the Hydrographic Department of Chinese Navy, c, Japanese Charts 相似文献
3.
JOHNH.KALIVAS 《地理学报(英文版)》1989,(1)
Care is required for multicomponent analysis if misleading results are to be avoided. The problem ofill-conditioned calibration matrices is of primary concern. This type of numerical instability isrepresented as spectral overlap of calibration spectra. Depending on the degree of spectral overlap, thesample concentration estimates can be severely affected. A practical statistical procedure is discussedwhich tests for the presence of spectral overlap among the pure-component spectra and simultaneouslyassesses the degree that concentration estimates may be degraded. Guidelines are developed to ascertainhow much departure from spectral orthogonality is acceptable. 相似文献
5.
In order to get a better knowledge of the air pollution levels of the urban air of Barcelona,twelvesamples from three stations of the air-monitoring control network were analysed.Each control station isrepresentative of a different environmental situation.Thus the station at Plaa Molina responds to asimple domestic and urban traffic situation;the station at Poble Nou to the influence of medium andsmall industries,mainly metallurgical;and the station at Montcada to a zone in which there existimportant industries,a cement factory,two highways and railroads.The total content of unsedimentable particles,three inorganic anions(chlorides,sulphates andnitrates)and six heavy metals(Fe,Pb,Cu,Mn,Cr and Cd)were determined on all the samples obtainedduring the same period of time.The use of an analytical scheme of sequential extraction has alsopermitted the subdivision of the total content of each metal into the following four fractions:(1)solubleor exchangeable;(2)associated with carbonates and/or with iron and manganese oxides;(3)bound toorganic matter;and(4)residual.The use of principal component analysis applied to the data as a whole showed the associations andcorrelations between the various parameters as well as between the different above mentioned fractions.The predominant presence of Cd in the‘soluble or exchangeable’fraction is confirmed,while the othermetals are mainly associated with the‘carbonates and/or Fe and Mn oxides’and‘bound to organicmatter’fractions.Hierarchical cluster analysis applied to the twelve samples showed clearly the presence of threedifferent classes closely related to the origin(station)of the samples.Thus it becomes feasible to proposefor each station a possible profile of the content in terms of the different parameters considered. 相似文献
6.
Data of the hydrolysis of adenosine 5'-triphosphate have been re-evaluated using a computer program thatnumerically integrates the differential rate equations within a routine that optimizes rate coefficients givena suitable model and concentration versus time data. The model is tested by calculation of Hamilton R-values, the Fisher F-statistic, a sensitivity analysis,the standard errors on the rate coefficients and by constructing contour maps of the objective functionversus two rate coefficients. An optimization using only phosphate concentration data cannot distinguish between a model in whichadenosine 5'-monophosphate is formed predominantly directly with a molecule of pyrophosphate, andone in which it is formed via adenosine 5'-diphosphate. A more accurate set of rate coefficients iscalculated from existing data and the relative importance of the two paths determined. 相似文献
7.
Li Wenyan 《地理学报(英文版)》1996,(3)
I.Introductionl.BasicfcatUresofportcitiesandthcirwhuencingfactorsTl1elhstoricalexperiencesofdevelopedcowtrieshavewitnessedtheessel1tialro1eplayedbyseaportsinpromotingdevelopn1entofnationaleconomy.Manyportcities,emergodfron1marinetransportation,supportedbyseaandlandroLrtesandflourishedn1ainlythroughindustryandtrade,oftenbecomendonalornationalecononhccenters.fu11ongti1eworld's2Omeqalopolesofmorethan6ntilIionpopulation,l2areportcities.AlmosteverycoUntrywiti1coastalline,longorshort,roprdsoneors… 相似文献
8.
The effect of peak shifts on the performance of a Kalman filter multicomponent analysis algorithm hasbeen investigated.A series of Gaussian test systems were employed to characterize the concentrationestimation errors and the morphology of the on-line residuals(the innovations sequence).Both forwardand reverse filters were used in the generation of the innovations sequences.It was found that thedifference between the forward and reverse innovations sequences gave an accurate indication of thedirection and magnitude of the peak shift.A series of overlapped two-component systems were alsoinvestigated.Again,a correlation between the difference innovations and the degree of the responseshift was observed.The behavior of the Katman filter in fitting the shifted fluorescence emissionspectrum of benzo[a]pyrene was also examined.The response for henzo[a]pyrene in cyclohexanesolution was compared to that obtained on the surface of a reversed phase thin layer chromatographyplate.A red shift of 4 nm was detected for the surface spectrum by observing the difference innovationssequence.This approach holds promise for correction of response shifts in multicomponent systems. 相似文献
9.
Liu Yanhua Zhao Mingcha Sun Huinan Institute of Geography CAS Beijing People''s Republic of China 《地理学报(英文版)》1997,(4)
Ｉ.ＴｈｅＰｏｓｉｔｉｖｅＲｏｌｅｏｆＢｒｏｗｎ’ｓＡｒｔｉｃｌｅＡｓａｆｏｒｅｉｇｎｓｃｈｏｌａｒ,Ｍｒ.Ｌ.Ｂｒｏｗｎｈａｓｋｎｏｗｎａｓｅｒｉｅｓｏｆｄａｔａａｎｄｍａｔｅｒｉａｌｓｏｎｐｏｐｕｌａｔｉｏｎ,ｆｏｏｄｐｒｏｄｕｃｔｉｖｉｔｙａｎｄｒｅｌｅｖａｎｔｆａｃｔｏｒｓｏｆＣｈｉｎａ,ｈａｄｍａｄｅｒａｔｈｅｒｄｅｅｐａｎａｌｙｓｉｓａｎｄｇｉｖｅｎａｆｏｒｅｃａｓｔｏｆｆｏｏｄｓｅｃｕｒｉｔｙｏｆＣｈｉｎａ.Ｈｅｈａｓｓｈｏｗｎｔｈｅｐｏｓｓｉｂｌｅｓｅｒｉｏｕｓｓｅｑｕｅｎｃｅｉｎｆｏ… 相似文献
10.
MARCIN SŁOWIK 《Geografiska Annaler: Series A, Physical Geography》2012,94(3):301-320
GPR and aerial surveys were conducted to study changes of channel pattern in the lower course of the Obra River (western Poland). The river is an example of an intensive anthropogenic transformation, however, the origin of the river pattern changes in its lower course is not obvious. The GPR measurements were done using a georadar MALÅ ProEx equipped with a shielded 250 MHz antenna. A 3D analysis of the GPR data supported with lithologic information indicated traces of a multi‐channel pattern. A variable orientation of sediment layering within channel bars and differences in channels depth and width pointed to changes of direction of the river bed migration. Analysis of aerial photographs and a satellite image indicated that only a few of the channels inferred from GPR could be discerned. The reason could be the more than 1 m thick fine sands layer covering all the alluvial structures. Analysis of historical maps from the eighteenth and the nineteenth centuries showed that 250 years ago the Obra was a meandering river. The maps illustrate also several meander cutoffs and decreased wetlands surface. The following transformations of the river bed pattern were discerned: 1. From braided to meandering channel pattern which could be a natural process caused by climatic and sediment transport rate changes that was also observed in case of other lowland rivers. 2. From meandering to sinuous pattern with channel islands and then to sinuous with oxbow lakes. However, further research is needed to study reasons and timing of the observed changes. 相似文献
11.
WANG Lei ZHANG Guang-Xin 《湿地科学》2006,4(3):193-197
1 INTRODUCTIONNitrogen and phosphorus in the water are the nu-trients limited in natural wetlands,which seriously in-fluence on the ecosystem production and the biodiver-sity(Mitsch,Grosselin,2000).Nitrogen and phos-phorus recycles have been interrupted b… 相似文献
12.
DONALD S.BURDICK XIN M.TU Institute of Statistics Decision Sciences Department of Mathematics Duke University Durham NC U.S.A.LINDA B.MCGOWN DAVID W.MILLICAN Department of Chemistry Drake University Durham NC U.S.A. 《地理学报(英文版)》1990,(1)
Fluorescence lifetime provides a third independent dimension of information for the resolution of totalluminescence spectra of multicomponent mixtures.The incorporation of this parameter into theexcitation-emission matrix(EEM)by the phase modulation technique results in a three-dimensionalexcitation-emission-frequency array (EEFA).Multicomponent analysis based on the three-dimensionalEEFA brings a qualitative change for the resolved spectra,i.e.individual spectra can be uniquely resolved,which is impossible with any two-dimensional analysis.In this paper we present a method for analyzingthe EEFA.We show mathematically that with the three-dimensional analysis of the EEFA individualspectra and lifetimes can be obtained.Our algorithm is developed in mathematical detail and isdemonstrated by its application to a two-component mixture. 相似文献
13.
《地理学报(英文版)》1992,(6)
NUMBER()R IGIN入L RES〔八RCH ARTICLESMathematiea!Model foro\\云怕姗吸。而己e audthe Optimization of the Reaetion BetweenZ,3一Bis(价tolyl)-P沁et、苗neU叭n嗯aFa改。\a\ DeS\沙M .A .M〔,,·ti,了、G.FI.“ro、,B.Del Casrillo,J.Alvar·e:一B“illa and P.J.Marrin5 imPle Validatory ToolsforJudgingthePredietivePerformaneeofPARAFACandThree一WayPLS刀.K 52221人人〕azzdD.月.Doorz7bosllW indowData 石.R.Faetor Analysis:Theoretieal Derivation and Applieation to Flow Injeetion Ana… 相似文献
14.
The Problem of studying eomPlex multicomPonent systems without seParation of theeomPonents 15 well known.Generally,the situation arises whenever interaetions betweeneomPonents are essential in determining the funetion of the system,notably in biochemiealsystems and in eatalysis.In eases sueh as these,the ultimate aim 15 to deduee the role of eaehof the eomPonents as well as the interaetions between them by 相似文献
15.
《地理学报(英文版)》1994,(Z1)
Contents0ftraceelementsins0i1sarec0ntr0lledbyb0thinterl1alandcxtcrl1alprocessesoft11eearth,alidtheirspatialdistributi0llpatternsarealsorelatedwit1itlleseprocesses.Thecllaracteristicsofthesepr0cessesareabletoberevea1edbystudyonthespatialdistributiol10ftraceelel11e11tcolltentsinsoils.A11u111be1'o1-methodshavebeenaPpliedtostudythcspatialdistributionoftraceelelnentc0nte11tsinsoils,among'these,geometricalinterpolation,movillgaverage,trendsurfaceanalysisandgeostatisticaltechniquesareoftenused[2,5,7]… 相似文献
16.
《地理学报(英文版)》1995,(1)
IntroductionIhthestudyofdistribution0fproduchon,wef0undasatoffaCtsthatproduCtonhadn0tbandistribUtedaccordingtDthenompllawsofthedistributionofproduCtion.'Forexamle,ashoemakerWhogotrickinSoutheaStAsiacamebaCktoNaning(inChina)anddistribUtedarestauranopsis,Ji… 相似文献
17.
Substructural fragment occurrence data are widely used as the basis for measures of inter-molecularstructural similarity.This paper investigates the effect of standardization on the effectiveness of suchmeasures using eight data sets for which both structural and biological activity data are available.Eightdifferent standardization methods are studied and it is shown that there is no significant difference in theeffectivenesses of the various methods;accordingly,any of them can be used for the calculation ofintermolecular structural similarity. 相似文献
18.
《地理学报(英文版)》1991,(6)
NUMBERREVIE认2 ARTICLETutorial to Robust Statisties P .J.Ro正Issee“、飞,ORIGINAL RESEARCH ARTICLESUse of the Wronskian Determinant in the Study of Mu.tieomPonent Systems 5.尸.兀口1)115,A.刃乃atLYclLv“nd D.FK改I“kis21Generalized Simulated Annealing for Calibration SamPIe Selection from an Existing Set andorthogonalization of Undesigned ExPeriments J .H.Kali仁,as 37八,门八,4乙U乙nSplitting of Calibration Data by Cluster Analysis 工Nae‘,a)Zd T. Isak夕50)7B《… 相似文献
19.
《地理学报(英文版)》1997,(1)
ＳｌｏｐｅｌａｎｄａｍｅｌｉｏｒａｔｉｏｎａｎｄｕｔｉｌｉｚａｔｉｏｎｗｉｔｈｃｏｍｐｌｅｘａｇｒｏｆｏｒｅｓｔｒｙｓｙｓｔｅｍｒａｉｓｅｄｂｙＰｒｏｆｅｓｓｏｒＨｕａｎｇＢｉｎｇｗｅｉｗａｓｍａｉｎｌｙａｉｍｅｄａｔｉｍｐｒｏｖｉｎｇｓｌｏｐｅｌａｎｄｓｕｓｔａｉｎａｂｌｅｐｒｏｄｕｃｔｉｖｉｔｙｂｙｕｓｉｎｇｂｉｏｌｏｇｉｃａｌｍｅａｓｕｒｅｓｆｏｒｔｈｅｐｕｒｐｏｓｅｏｆｐｒｏｖｉｄｉｎｇｎｅｗｍｅｔｈｏｄｆｏｒｆｕｔｕｒｅｃｏｍｐｒｅｈｅｎｓｉｖｅｅｘｐｌｏｉｔａｔｉｏｎａｎｄｕｔｉｌｉ… 相似文献
20.
《地理学报(英文版)》1990,(6)
NUMBERIRLVI「、、,ARTI〔、L〔Nl ixture Analysis using Faetor Analysis.11:Self-modeling Curve Resolution J.(’.H(22,z;/l(川‘22,(1 P.J.Ge一,,/)c一了izze〔)R I61NAL RFS〔AR(,H ARTI(,IFSResolution of MultieomPonent FluoreseentExeitation一Emission一Frequeney Array D .5.Bll“/l‘k.无’.M.7’li、L.B.九了cG阴曰7M ixtures by Analysis of thea,2‘了D.班Mzjjj‘、az715Tensoria!Resolution:a Direet Trilinear Deeomposition 百.写‘,27(7,召二‘222(1 B.R.K()、、丫z八ki2947The Effeet … 相似文献