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1.
Gaschromatographic Determination of Diethylenetriaminepentaacetic Acid in Surface Water. A method for the determination of diethylenetriaminepentaacetic acid (DTPA) is reported. The determination is based on the preconcentration on a strong base anion exchange resin, esterification with n-propanol and following gaschromatographic separation using a N-selective detector. The sensitivity of the method, including enrichment, is 1 μg/L in river water. The identity of DTPA in river water was proved by mass spectrography. The method can be used also for the quantitative determination of nitrilotriacetic acid (NTA), ethylenediaminetetraacetic acid (EDTA), cyclohexanediaminetetraacetic acid (CDTA) and ethyleneglycolbis-(2-aminoethylether)-N,N,N′,N′-tetraacetic acid (EGTA). The method was used to examine river water. An investigation along the river Rhine, taking grab samples from January and february 1992 showed that DTPA was present in some sampling places in similiar concentrations as NTA and EDTA.  相似文献   

2.
The New EC Framework Water Directive: Assessment of the Chemical and Ecological Status of Surface Waters The main objective of the draft EC Framework Water Directive is the good quality of all surface waters. The directive provides for an assessment of the chemical status of surface waters (EU‐wide valid environmental quality standards for approximately 30 priority substances) and a five‐stage ecological classification of waters, comprising the stages high, good, moderate, poor, and bad. The starting point for the assessment are the reference conditions, which are defined as corresponding to high water quality and characterising a water status with no significant anthropogenic impact. The reference sites in the various water body types are to be selected using hydromorphological and physico‐chemical parameters and subsequently characterised by means of biological parameters. For surface waters, three groups of characteristics are provided for, namely: 1. with priority the biology – in the case of surface waters – with the four elements phytoplankton, macrophytes/phytobenthos, benthic invertebrate fauna, and fish fauna; 2. supporting the hydromorphology, e.g. flowing waters with the three elements hydrological regime, river continuity, and morphological conditions and 3. supporting the physico‐chemical conditions with the three elements general conditions, specific synthetic pollutants, and specific non synthetic pollutants (other than the priority substances of the chemical status).  相似文献   

3.
With the Water Framework Directive (WFD) the European Commission (EC) is requested to define environmental quality standards for pollutants to protect aquatic life in surface waters. Quality standards have to be derived by a scientific risk assessment and should not be exceeded. The recommended quality standards are mainly based on long term toxicological tests with algae, crustaceans and fish. The lowest effect concentration is divided by an assessment factor between 10 and 1000, which considers the data quality and quantity. In this work funded by the German Länder Working Party on Water (Länderarbeitsgemeinschaft Wasser – LAWA) environmental quality standards for 40 considered relevant substances were derived for aquatic ecosystems. The data sheets cover the identification of the compounds, their behaviour in the environment (physical‐chemical properties, biotic and abiotic degradation, sorption, bioaccumulation), information about mode of action, uses, analytical determination and available quality criteria. Ecotoxicological effect concentrations for bacteria, algae, protozoa, aquatic plants, crustaceans, fish, amphibians, insects and molluscs are listed. For 17 of the 40 hazardous substances investigated, quality objectives above 1 μg/L were derived. For 12 substances the values were between 0.1 μg/L and 1 μg/L and for 5 substances lower than 0.1 μg/L. Incomplete ecotoxicological data sets of the remaining compounds do not allow the derivation of quality standards. Especially for drugs further ecotoxicological test results are needed.  相似文献   

4.
Distribution of Natural and Synthetic Estrogenic Steroid Hormones in Water Samples from Southern and Middle Germany Natural and synthetic hormones can reach surface waters via domestic sewage effluents. For drinking water production, bank filtration of river waters is a common procedure and hormone contaminations can potentially reach groundwater levels and drinking water sources. In order to analyse steroid hormones in the different aquatic compartments (raw sewage and effluent, surface water, groundwater, raw and drinking water) of South and Middle Germany, a sensitive analytical method was developed and employed to detect the natural steroid hormones estradiol (E2) and estrone and the synthetic estrogen ethinylestradiol (EE2). Samples which were taken in two subsequent series were subjected to clean‐up and enrichment procedure and subsequently analysed by HPLC‐MS. The limit of quantitation for the method was determined to be 0.05 to 0.5 ng/L, depending on the matrix. By treating the samples with glucuronidases/arylsulfatases, conjugates were amenable to analysis and the sum of conjugates and unconjugated steroids was calculated. In raw sewage, the median of the concentrations of the unconjugated steroids was 7 ng/L for EE2, 1.5 ng/L for E2, and 5.5 ng/L for estrone. After cleavage of conjugates, the medians of total steroids were 9.5 ng/L (EE2), 3 ng/L (E2), and 13 ng/l (estrone). Conjugates therefore contributed up to 50 % of the total steroid concentration in raw sewage. In treated effluents, the concentrations of steroids were much lower than in the raw sewage. The medians of free steroids were determined to be 0.3 ng/L for EE2, 0.2 ng/L for E2, and 2.5 ng/L for estrone. Overall the medians in the effluent were thus less than 10% of those in the influent. Conjugates still contributed significantly (40% and more) to the steroid concentrations (medians: EE2: 0.5 ng/L, E2: 0.8 ng/L, and estrone: 8 ng/L).  相似文献   

5.
Concepts for the Evaluation of Contaminant Mobility in Soil and Waste Materials Elution tests (S4, pHstat, and SDS test) are presented, enabling the evaluation of the mobility of hydrophilic/hydrophobic and inorganic/organic contaminants in soil and waste materials. While elution tests for estimation of the mobilization potential of hydrophilic substances are performed following the pHstat method, for hydrophobic species surfactant-containing eluents are used. The individual parameters of the elution process are selected assuming a "worst-case" scenario. In principle, because of economic reasons, detailed analytical investigations should be preceded by relevant screening tests.  相似文献   

6.
The results of a series of investigations are presented, performed by the governmental chemical laboratory Karlsruhe (CLUA) in order to determine pesticides in drinking water for purposes of food monitoring. 231 samples of 8 municipal water supplies (groundwater wells/no bank filtrate) and 34 private water supplies close to the bank of the river Rhine (groundwater wells/partly bank filtrate) were analysed. The sampling sites were located between Mannheim and Greffern, Germany. In 1986 high amounts of atrazine and simazine were determined in the drinking water wells of several private water supplies, especially at the sampling sites in the south. The likewise high chloride content of the samples was taken as a proof of bank filtrate contributing to the water. The decrease of atrazine load in the river water of the Rhine since 1987 has its parallel in the analytical results for the concerned drinking water wells. Obviously the pesticide contamination of water from bank filtrate pumping wells is mainly depending on the pesticide load of the river water. The application of fertilizers and pesticides in the fields seems not to be a significant source of the pesticide contamination of dringing waters derived from bank filtrate water. For reasons of public health a monitoring of pesticide content in bank filtrate pumping wells of private water supplies is recommended.  相似文献   

7.
Occurrence of Industrial Chemicals (HPS, BPS, and SPS) in Surface Water The paper gives the results of water examinations for different phenylsulfonamides. Random samples taken every month between May 1999 and August 2000 from surface water out of the river Rhine (kilometer 838), the river Ruhr (Mülheim Styrum) and the river Emscher (Oberhausen center) were tested for the corrosion inhibiting agent 6‐[methyl(phenylsulfonyl)amino]‐hexanoic acid (HPS) as well as its metabolites 4‐[methyl‐(phenylsulfonyl)amino]‐butanoic acid (BPS) and sarkosin‐N‐(phenylsulfonyl) (SPS). Furthermore, the sewage plant effluents of two municipal wastewater treatment plants from the rural area were also included in the monitoring program. The analytical method includes solid‐phase extraction (SPE), a derivatization step as well as gas chromatography mass spectrometry (GC‐MS). SPS is regularly found in all investigated surface waters, but only occasionally in the effluents of the two rural sewage plants. The median values for SPS amount to 0.09 μg/L in the river Rhine, 0.60 μg/L in the river Ruhr, and 0.70 μg/L in the river Emscher. BPS can only be found in the river Ruhr (median value: 0.08 μg/L) and in the river Emscher (median value: 0.41 μg/L). HPS was regularly found in a surface water for the first time. This substance can be detected in the Emscher through the whole measurement period. The median value for HPS amounts to 1.78 μg/L. Aditionally, the validation characteristics of an alternative analytical method including solid‐phase microextraction (SPME) is worked out. The fully automated process includes an on‐fiber methylation step and the GC‐MS. The repeatability standard deviation of the process amounts to RSD < 12%. Detection limits between 0.07 and 0.70 μg/L are achieved.  相似文献   

8.
By means of UV spectra of cyclohexane extracts from aquatic sediments it is possible to distinguish: “normal” mineral oil aromatics (e. g. of the middle distillation fraction), used oils, and highboiling raffinates, tar oils, and — as representative of aromatics listed in the German drinking water ordinance — fluoranthene. Starting with less selective extractants and the basic UV spectra, it is shown that spectra of higher orders frequently allow a quantitative determination of fluoranthene. If it is justified to assume a constant conversion factor, the result of the measurement can be used to calculate the contents of the whole group of aromatics listed in the German drinking water ordinance. A comparison with other methods (HPLC etc.) and with results from other laboratories showed good agreement. Finally, the diagnostic capacity (fingerprint) of derived spectra is pointed out.  相似文献   

9.
Assessment and Modification of Arsenic Mobility in Contaminated Soil Arsenic concentration in the seepage of contaminated soils of an old tannery site is assessed using batch and column experiments. The effect of reducing conditions, pH, and ionic strength is also investigated. The iron oxide rich subsoil (C‐horizon) is the main source of groundwater pollution with arsenic. In this horizon, mobilization can increase as a result of reducing conditions upon periodical water saturation. Therefore, the potentially mobile arsenic is determined by a reductive dissolution of the poorly crystalline iron oxide fraction using 0.1 M ascorbic acid. Arsenic concentration can be reduced from 100 μg/L to below 20 μg/L by an increase of ionic strength (e.g. by a 0.01 M CaCl2 solution). Arsenic contaminated soils should be limed regularly in order to maintain the highest possible calcium concentration in the soil solution.  相似文献   

10.
Investigations of the Adsorptive Separation of Volatile Chlorinated Hydrocarbons (VCHC) from Water with Humic Substance by Novel Polymeric Adsorbents and Activated Carbons. Part II: Dynamics of Adsorption In this publication, the dynamics of adsorption of different volatile chlorinated hydrocarbons (VCHC) (1,2-dichloroethane, 1,1,1-trichloroethane, trichloroethene) and a humic substance from water as well as of these VCHC from water with humic substance onto novel polymeric ad-[QJ][HR] sorbents (WOFATIT EP 63, DOWEX XUS 43493, MACRONET MN 100 and MN 200) was studied in comparison to activated carbons (NORIT ROW 0.8 SUPRA, PRECOLITH BKK 3, HYDRAFFIN CG). The obtained breakthrough curves and the following predicted characteristic values reveal that the polymeric adsorbents do not remove or remove the humic substance only with low adsorption capacity in contrast to the activated carbons. At the adsorption of the VCHC from water with humic substance it was determined that the influence of the humic substance on the adsorption capacity is substantially less on polymeric adsorbents than on activated carbons.  相似文献   

11.
Short-term Toxicity Tests for the Measurement of Toxicity of Chemicals Towards Activated Sludge. To avoid severe damage to the activated sludge of a wastewater treatment plant it is necessary to control the sludge activity by means of biological test systems. Especially the short-term respiration assay and the dehydrogenase assay with resazurin as a redox-dye seem to be appropriate for this monitoring program. The practical performance of both test systems was optimized in some essential points. With the help of several reference substances both monitoring systems were tested for practical use as short-term toxicity tests. The results of the investigations showed that the inhibitory concentrations measured in both test systems were partially very different. In monitoring experiments with laboratory-scale wastewater treatment plants it could be shown that a positive correlation between respiration activity and dehydrogenase activity is not always given. Furthermore, a pH-dependent toxicity could be demonstrated for several substituted phenols.  相似文献   

12.
Die Beurteilung des gentoxischen Potentials in Oberflächenwasser erfordert Testmethoden, die DNA-Schäden in relevanten Organismen der aquatischen Biozönose hinreichend empfindlich erfassen. Die Mikrogelelektrophorese (MGE), auch comet assay genannt, ist solch ein gentoxikologischer Indikatortest, mit dem DNA-Strangbrüche und Alkalilabile Stellen der DNA eukaryontischer Organismen bzw. Zeilen sensitiv nachgewiesen werden können. In der vorliegenden Studie werden Ergebnisse des Einsatzes der Mikrogelelektrophorese an einzelligen Grünalgen der Spezies Chlamydomonas reinhardtii und Protozoen der Spezies Acanthamöba castellanii vorgestellt. Es werden Validierungsuntersuchungen mit gentoxischen Einzelsubstanzen wie z.B. 4-Nitrochinolin-1-oxid, Benzo(a)pyren usw. präsentiert. Außerdem wird die Untersuchung einer nativen Wasserprobe der Weißen Elster, die mit verschiedenen Konzentrationen eines EPA-Standards aufgestockt wurde, vorgestellt. Die beiden Testorganismen wiesen erwartungsgemäß eine unterschiedliche Sensitivität gegenüber verschiedenen Einzelsubstanzen auf. Die niedrigsten Effektkonzentrationen für beide Organismen konnten für 4-Nitrochinolin-1-oxid mit 1...10 μg/L ermittelt werden.  相似文献   

13.
Precipitation of Aluminium and Phosphate Affected by Acidification Acidified waters often show elevated concentrations of Al (with up to 6 mg L–1 being not unusual). A pH increase resulting e.g. from mixing with non‐acidified water or from biological activities may be linked with Al precipitation. Up to now, this phenomenon was described for acid mine drainages. This investigation focuses on a whitish precipitate naturally formed in a brook of an atmospherically acidified catchment in the Ore Mountains, Germany. Based on infrared spectra the precipitate was identified as an Al‐hydroxosulfate with crystal water. A simulation of natural conditions in the laboratory showed that Al precipitated only if sulfate or phosphate ions were added to the solution. In the case of sulfate being added, the infrared spectrum of the precipitate was similar to the natural precipitate. 27Al NMR spectroscopy revealed tetrahedrally coordinated Al in some precipitates which evidences the participation of the tridecameric [Al13O4(OH)24(H2O)12]7+ cation beside other polymeric Al cations. Precipitation experiments subjected to the given conditions showed that the phosphate elimination from solution with Al was much higher than with Fe. With Al and Fe added together, the P elimination rate was likewise high, and phosphate was bound onto Al in the precipitate. This was demonstrated by SEM‐EDX spectroscopy. Based on these results we present a possible reaction mechanism. The precipitation of Al together with P allows a significant retention of both elements in sediments because in contrast to Fe, Al immobilizes phosphate even under anoxic conditions.  相似文献   

14.
Indicating the Trophic State of Running Waters by Using TIM (Trophic Index of Macrophytes) – Exemplary Implementation of a New Index in the River Inninger Bach The river Inninger Bach represents the outflow of the lake Wörthsee (Bavaria). The mean pH of the calcareous river has a value of ca. 8 during the vegetation period, the mean conductivity is about 350 to 400 μS/cm. The macrophyte vegetation of the river course was mapped and the nutrient concentrations of both the water body and the sediment were measured. In every mapping section the Trophic Index of Macrophytes (TIM) was calculated. By cluster analysis the mapping sections were grouped into three zones which differed in macrophyte vegetation. These differences are not associated with varying nutrient concentrations but are mainly due to differences in the degree of shading. In spite of the characterisation of the lake Wörthsee as oligo‐mesotrophic the river Inninger Bach, which represents the outflow of the lake Wörthsee, is classified as meso‐eutrophic by the Trophic Index of Macrophytes TIM. The increased trophic state of the river compared to the lake is caused by the river Krebsbach, a small tributary flowing into the river Inninger Bach only a short stretch downstream of its outflow of the lake Wörthsee. The river Krebsbach shows a total phosphorus concentration of about 56 μg/L P. The input of diaspores of submerged macrophytes both from the oligo‐mesotrophic lake Wörthsee and the eutrophic river Krebsbach leads to a submerged vegetation comprising species with different optima in regard to the trophic situation. This is one of the main reasons why many values of the TIM have to be labeled as “not sure”.  相似文献   

15.
Formation of Brominated Disinfection By-products after Chlorination of Water from Lake Constance Depending on Treatment Steps and Bromide Concentration The formation of halogenated disinfection by-products (DNP) (trihalomethanes (THM), haloacetic acids (HES), haloacetonitriles (HAN), haloketones (HKE) and chloropicrin (TCNM)) was studied after chlorination (0.5 mg/L) of raw water and drinking water from Lake Constance. The objectives of this study were to investigate the effect of bromide ion on the distribution of DNP-species resulting from chlorination and to draw up a bromide mass-balance. The treatment of water from Lake Constance with ozone decreased the formation of DNP about 35% and of total organic halogens (AOX) about 45%. This decline in DNP-formation is mainly due to the formation of chloroform, dichloro- and trichloroacetic acid. Though there is only a small amount of bromide (6.2 μg/L) in water from Lake Constance, about 32% of THM, 16% of HES, and 30% of HAN contained bromine after chlorination of treated water. The addition of bromide ion (up to 1 mg/L) shifted the DNP-composition to more brominated species. The distribution of the DNP-species depends on the initial molar bromide-to-chlorine ratio. A mathematic model showed the same pattern of DNP-species depending on the initial molar bromide-to-chlorine ratio that was observed experimentally in microstrained raw water and drinking water from Lake Constance. After chlorination of microstrained raw water, 27% of the bromide were incorporated in known DNP, 34% in unknown substances, and about 39% of bromide were not converted to organic bromine. After chlorination of treated water, only 16% of the bromide were incorporated in unknown substances, whereas 34% were found in known DNP. About 50% were found as bromide again. After addition of bromide (up to 25 μg/L) to ozonated and treated water from Lake Constance, between 60 and 72% of the bromide that had reacted after chlorination were found in analyzed low-molecular DNP.  相似文献   

16.
Effective biodegradation of organic compounds is one of the major objectives while optimizing biological drinking water treatment processes. Enhancing the biological activated carbon (BAC) filter performance with nutrient addition was studied using chemically pre-treated and ozonated lake water. Three parallel pilot-scale biofilters were operated: one with phosphorus addition, one with a mixture of inorganic nutrients addition, and one as a reference. The addition of nutrients had no statistically significant influence on the natural organic matter (NOM) removal when monitored by total organic carbon (TOC), UV absorbance, and assimilable organic carbon (AOC). However, the addition of nutrients significantly increased the heterotrophic plate count (HPC) bacteria of the filter effluent, while the adenosine triphosphate (ATP) analysis of the attached bacteria did not show any increase in BAC filters. It seemed that in BAC filters the bacterial growth was limited by phosphorus, but the increased bacteria could not attach themselves during the relatively short acclimatization period.  相似文献   

17.
Does the Structural Quality of Running Waters Affect the Occurrence of Macrophytes? The morphological structure plays, besides e.g. nutrient concentration, an important role for the integrated assessment of running waters. This paper focuses on the relationship between structural quality and macrophyte vegetation. During summer 2000 structural quality according to LAWA, macrophyte vegetation, and selected habitat parameters were recorded in 135 mapping sections in running waters in Southern Germany. In streams of high structural diversity, generally higher species richness is expected than in rivers of low diversity of habitats. However, no significant differences in macrophyte species richness were detected between different classes of structural quality. In contrast, bryophytes alone showed a significant decrease in species richness with degradation of structural quality. The number of species of other macrophytes increased, respectively. The relationship between occurrence of macrophytes, structural quality, and other environmental variables was analysed using canonical correspondence analysis. Rivers of high structural quality mostly showed high flowing velocities and were heavily shaded. These environmental conditions, which characterize river types of mountainous regions, were predominantly tolerated by bryophytes. Vascular plants and charophytes generally prefer slowly flowing and unshaded habitats. River types exhibiting these environmental conditions often are more influenced by human activities and are more structurally degraded, respectively. With respect to these fundamental differences between river types, species richness of macrophytes and class of structural quality are not correlated when all types of rivers are taken into account. Type‐specific ecomorphological parameters, which conceal the differences in species richness caused by structural quality, are discussed. Structural degraded rivers can provide good environmental conditions for vascular plants and charophytes. To predict macrophyte species richness from structural quality, a differentiation of river types is essential.  相似文献   

18.
For the establishment of the EC Water Framework Directive in Germany the physico‐chemical reference conditions of surface waters in Germany had to be determined. The results of the statistical analysis of 3500 data sets of 31 surface water catchment types show that water body types can be aggregated to bogs and bog riverside meadows, saliniferous type, carbonatic‐dolomitic type, sandy‐clayey type, silicatic type, and metallogenic type. The data base allows an assessment of the plausibility of the surface water quality classification and quality targets of the LAWA (Länderarbeitsgemeinschaft Wasser). The investigated reference status of the natural surface waters for the considered elements in the suspended particulate matter, except in metallogenic landscapes, corresponds to the water quality class I of the LAWA. The reference conditions of cadmium and mercury in the total water phase are significantly higher than the quality targets of the LAWA. The evaluated reference data of the other physico‐chemical parameters in the total water phase show, that assessable physico‐chemical parameters refer to a quality class of I, mainly and quality class II, locally. Mainly, the data reached the quality targets of the LAWA. In spite of the hard evaluation criteria to separate reference sites a special enrichment of nitrate and cadmium was found in many German surface water reference catchment types.  相似文献   

19.
Designation and Assessment of Artificial and Heavily Modified Water Bodies under the EC Water Framework Directive The EC Water Framework Directive allows the Member States to designate artificial and heavily modified water bodies under specific conditions. For those water bodies the ecological assessment and the resulting programmes of measures will be based on the “maximum ecological potential” as reference conditions and not on the “high ecological status”, which has to be used for natural water bodies. Such designation is possible only, if the hydromorphology of the water bodies concerned has been substantially changed in character to maintain specified uses. The criteria for the designation are fulfilled, if restoration measures needed to meet the high ecological status would have significant adverse effects on the uses and if no other better environmental options would exist to maintain the specified uses. In late 1999 the EC‐Working Group on Heavily Modified Water Bodies (HMWB) has been established to develop criteria for the designation of artificial and heavily modified water bodies as well as for the determination of the maximum ecological potential. The working group has produced the guidance document “Identification and Designation of Artificial and Heavily Modified Water Bodies” in November 2002, which has been agreed by the European Water Directors on 21 November 2002 in Copenhagen. The guidance document is focusing on two time borders, the provisional identification of heavily modified water bodies until 2004 and the legally binding designation as artificial and heavily modified in the first river basin management plan in 2009 at the latest. The guidance document considered the main findings of 34 case studies for rivers, lakes, transitional and coastal waters carried out in 11 European countries. The results of the case studies as well as a summarizing synthesis were used as a fundamental basis to produce the guidance document. The practical examples given by the case studies were compiled as a toolbox which supplements the guidance for the purpose of its better application.  相似文献   

20.
Competitive solid phase enzyme immunoassays using polyclonal antibodies were developed for the detection of the phenoxycaboxylic acids MCPB [4-(4-chloro-2-methylphenoxy)butyric acid], Mecoprop [2-(4-chloro-2-methylphenoxy)propionic acid], and 2,4-D [(2,4-dichloro-phenoxy)acetic acid] in drinking water and ground water. The carrier protein for the immunization was bovine serum albumin, horseradish peroxidase conjugates were employed as enzyme tracer. For the three antisera, the optimization of detection limits and test sensitivities was our first consideration. For the mecoprop and 2,4-D antisera, the strongest influences were the pH value and the ionic strength, as much as the use of enzyme tracers with lower affinities. The MCPB antiserum reacted with 2,4-DB[4-(2,4-dichlorophenoxy)butyric acid] with equal specificity, either could be detected at 0.02 μg/L (80% B/B0), middle of the test (50 B/B0) lying at 0.1 μg/L. The detection limit with mecoprop antiserum was optimized to 0.02 μg/L, the prescribed limit for drinking water of 0.1 μg/L ling at 60 % B/B0. The strongest cross-reactivity was found for mecoprop methyl ester. MCPB. 2,4-DB, and dichloroprop have crossreactivities of 50%, 6.7%, and 6.3%, respectively. The 2,4-D antiserum reacts less sensitively with 2,4-D, the detection limit being 0.4 μg/L. The 2,4-D isooctyl ester and 2,4-D methyl ester demonstrate as cross-reacting compounds high cross-reactivites of 3630% and 2230%. The cross-reactions of the compounds 2,4-DB, MCPB, and MCPA [(4-chloro-2-methylphenoxy)acetic acid] lie at 52%, 69%, and 41%. 100 ground water tests were spiked within laboratory. All positive samples were correctly identified. Falsely negative results did not appear.  相似文献   

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