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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.
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   

3.
I.Introductionl.BasicfcatUresofportcitiesandthcirwhuencingfactorsTl1elhstoricalexperiencesofdevelopedcowtrieshavewitnessedtheessel1tialro1eplayedbyseaportsinpromotingdevelopn1entofnationaleconomy.Manyportcities,emergodfron1marinetransportation,supportedbyseaandlandroLrtesandflourishedn1ainlythroughindustryandtrade,oftenbecomendonalornationalecononhccenters.fu11ongti1eworld's2Omeqalopolesofmorethan6ntilIionpopulation,l2areportcities.AlmosteverycoUntrywiti1coastalline,longorshort,roprdsoneors…  相似文献   

4.
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   

5.
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   

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   

7.
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   

8.
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   

9.
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   

10.
I.ThePositiveRoleofBrown’sArticleAsaforeignscholar,Mr.L.Brownhasknownaseriesofdataandmaterialsonpopulation,foodproductivityandrelevantfactorsofChina,hadmaderatherdeepanalysisandgivenaforecastoffoodsecurityofChina.Hehasshownthepossibleserioussequenceinfo…  相似文献   

11.
2005年12月中、下旬对松花江哈达湾至佳木斯江段冰封期江水和沉积物进行了采样与分析。结果表明,江水总汞质量浓度为29.74~136.88 ng/L,均值为50.21 ng/L,以悬浮颗粒态为主(53.38%~85.99%)。沉积物总汞的质量分数介于0.013~1.543 mg/kg之间,与铁、锰和有机碳含量呈显著正相关;运用连续化学浸提法,对哨口至松原江段沉积物汞的形态进行了分析,沉积物汞主要以碱溶态、强有机质结合态和残渣态存在,可交换态和盐酸溶态汞的比例较小,仅占总汞的0.91%~33.7%。研究发现,沉积物再悬浮作用是影响松花江冰封期江水悬浮颗粒态汞及总汞空间分布的主要因子,沉积物汞释放是一个缓慢长期的过程。  相似文献   

12.
哈达山水利枢纽对第二松花江下游地区汞污染的影响   总被引:1,自引:0,他引:1  
通过调查第二松花江10个典型断面沉积物、江水中总汞及江水中不同形态的汞浓度,研究了建坝对于库区汞污染的影响。建坝之后,由于水文条件改变,悬移质发生沉降,库区沉积物中汞浓度将会增加,库区会变成汞的汇。库区下游出水处江水汞浓度将降低至0.032 μg/L。每年通过推移质输沙向库区输入约4.37 kg汞,通过悬移质输沙向库区输入约856.8 kg汞。由于输沙的影响,每年将会在库区形成厚约1.23 cm的沉积物。库区上游沉积物的再悬浮、水库淹没区汞的溶出,对库区汞通量影响不大。  相似文献   

13.
Baseflow is an important component of river or streamflow. It plays a vital role in water utilization and management. An improved Eckhardt recursive digital filter(IERDF) is proposed in this study. The key filter parameter and maximum baseflow index(BFImax) were estimated using the minimum smoothing method to improve baseflow estimation accuracy. The generally considered BFImax of 0.80, 0.50 and 0.25 according to the drainage basin's predominant geological characteristics often leads to significant errors in the regions that have complex subsurface and hydrologic conditions. The IERDF improved baseflow estimation accuracy by avoiding arbitrary parameter values. The proposed method was applied for baseflow separation in the upstream of Yitong River, a tributary of the Second Songhua River, and its performance was evaluated by comparing the results obtained using isotope-tracer data. The performance of IERDF was also compared with nine baseflow separation techniques belonging to filter, BFI and HYSEP methods. The IERDF was also applied for baseflow separation and calculation of rainfall infiltration recharge coefficient at different locations along the Second Songhua River's mainstream for the period 2000–2016. The results showed that the minimum smoothing method significantly improved BFImax estimation accuracy. The baseflow process line obtained using IEDRF method was consistent with that obtained using isotope 18 O. The IERDF estimated baseflow also showed stability and reliability when applied in the mainstream of the Second Songhua River. The BFI alone in the river showed an increase from the upstream to the downstream. The proportion of baseflow to total flow showed a decrease with time. The intra-annual variability of BFI was different at different locations of the river due to varying climatic conditions and subsurface characteristics. The highest BFI was observed at the middle reaches of the river in summer due to a water surplus from power generation. The research provided valuable information on baseflow characteristics and runoff mode determination, which can be used for water resources assessment and optimization of economic activity distribution in the region.  相似文献   

14.
我国东部河水的化学地理特征   总被引:11,自引:0,他引:11  
本文讨论我国东部河水的重要理化指标、化学稳定性、酸和碱的缓冲容量及区域分异特征,并分析影响河水水质的地球化学因素。  相似文献   

15.
松花江上游地区汞污染的化学生态效应   总被引:5,自引:0,他引:5  
王宁  朱颜明  朴明玉  孟丹 《地理科学》2005,25(6):737-741
采样分析了吉林省东部松花江上游金矿开采区及其附近水、土壤、动植物及河流沉积物样品中汞的含量,发现河流沉积物中汞的污染相当严重;受其影响当地的植物和两栖类动物——中国林蛙体内总汞和甲基汞含量也明显高于对照组。实验表明,林蛙内脏对汞的富集能力大于肌肉;秋季对汞的富集大于春季;河流沉积物中甲基汞的含量与林蛙体内甲基汞的含量有较好的正相关。汞污染的来源与区域内个体金矿的滥采滥排有直接关系,表明人类活动所产生的有毒重金属在地表过程中出现了化学生态效应。  相似文献   

16.
Based on the continuous monitoring data of hydrology and water quality in the period from 1972 to 1997, the responses of hydro-environment system to melt water in the Second Songhua River basin were derived. Because of melt water, the water quality in the Second Songhua River is good and changes very except that the contents of Hg and Mn in the water are higher. The contribution of melt water to the water fluxes in the Second Songhua River basin is distinct: the water flow in April increases remarkably, reaches the peak in the upper reaches. The pollutant contributions and water pollution indices (WPIs) of the Second Songhua River in April are high in the upper reaches while that in the lower reaches are low. The responses of hydro-environment system to melt water of that basin are affected by content of packed snow and the underlining surface systems.  相似文献   

17.
准确评价地下水对河水的补给量是流域水资源量管理和合理利用的基础。在马莲河流域下游采集不同季节地表水和地下水样品75组,利用Cl-、电导率(EC)和D、18O同位素多方法联合评价,识别了地下水补给河水的位置、补给量及其季节变化。结果表明:马莲河水EC和Cl-质量浓度沿着流向均呈降低趋势,δD和δ18O值沿流向减小。雨季EC和Cl-质量浓度最低,δD和δ18O值最高。地下水各组分浓度均低于河水,时空变化不明显。地下水单宽排泄量存在时空变异,上段和下段为地下水强排泄区,中段地下水排泄较弱,不同季节地下水排泄量占总排泄量的72.20%~95.07%。雨季地下水单宽排泄量显著降低,河水中基流比例由雨季前期的68.89%降至29.43%。整体上,地下水补给河水季节变化明显,而空间变化规律较为稳定。研究成果有利于深入认识河水和地下水的相互作用机制,并为当地水资源利用提供基础依据。  相似文献   

18.
Based on the continuous monitoring data of hydrology and water quality in the period from 1972 to 1997, the responses of hydro-environment system to melt water in the Second Songhua River basin were derived. Because of melt water, the water quality in the Second Songhua River is good and changes very except that the contents of Hg and Mn in the water are higher. The contribution of melt water to the water fluxes in the Second Songhua River basin is distinct: the water flow in April increases remarkably, reaches the peak in the upper reaches. The pollutant contributions and water pollution indices (WPIs) of the Second Songhua River in April are high in the upper reaches while that in the lower reaches are low. The responses of hydro-environment system to melt water of that basin are affected by content of packed snow and the underlining surface systems.  相似文献   

19.
YAN Denghua  DENG Wei  HE Yan 《地理学报》2002,12(3):289-294
Based on the continuous monitoring data of hydrology and water quality in the period from 1972 to 1997, the responses of hydro-environment system to melt water in the Second Songhua River basin were derived. Because of melt water, the water quality in the Second Songhua River is good and changes very except that the contents of Hg and Mn in the water are higher. The contribution of melt water to the water fluxes in the Second Songhua River basin is distinct: the water flow in April increases remarkably, reaches the peak in the upper reaches. The pollutant contributions and water pollution indices (WPIs) of the Second Songhua River in April are high in the upper reaches while that in the lower reaches are low. The responses of hydro-environment system to melt water of that basin are affected by content of packed snow and the underlining surface systems.  相似文献   

20.
青海省湟水河西宁段重金属元素的污染和评价   总被引:1,自引:0,他引:1       下载免费PDF全文
曾方明 《盐湖研究》2017,25(2):8-12, 59
湟水河是西宁市的重要河流。开展湟水河西宁段沉积物的重金属研究对西宁市的环境保护和生态建设具有重要意义。本次研究对湟水河西宁段表层泥质沉积和河水以及流域内的现代菜地表土和松树苗地表土的重金属含量进行了测定。同时,采用全新世以前的黄土、湟水河一级阶地的砂质沉积给出了西宁市自然状态下的重金属背景值。各类样品的重金属元素含量结果表明:1)自然状态下,Pb为29.5 mg/kg,As为15.6 mg/kg,Hg为0.01 mg/kg,Cd为0.18 mg/kg,Cr为31.1 mg/kg。2)河流表层泥质沉积的重金属含量平均值,Pb为45.2 mg/kg,As为7.8 mg/kg,Hg为0.02 mg/kg,Cd为0.48 mg/kg,Cr为48.8 mg/kg。3)总体上,河流表层泥质沉积、现代菜地表土和松树苗地表土的Cd、Pb、Hg、Cr均比自然状态下的背景值要高。4)湟水河西宁段已出现较明显的重金属污染,应控制Cd等重金属元素向河流中的排放。  相似文献   

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