bluuebunny/crossref_metadata_2025_split huggingface dataset:
Salinity Tolerance and Salinity Induced Changes in Ionic and Metabolite Composition in a Penaeid Prawn, Parapenaeopsis sculptilis (Heller)
Authors: Kundu Rahul , Prasad V. V. Sivaram , Mansuri A. P. 
Published: February 2007

AbstractSummary: Experiments were carried out to study the salinity tolerance and the impact of salinity changes on ions and metabolite in the body of a marine penaeid prawn, Parapenaeopsis sculptilis. Juveniles of this prawn species have a comparatively wide range of salinity tolerance than adults. Juveniles can tolerate 60 … 100 %, but adults only 100 % seawater concentrations. Behavioural observations showed that the juvenile and adult prawns became inactive with decrease in seawater concentrations followed by paralysis and death. Death occurred probably due to failure of the neuromuscular system. A highly significant variation existed in the amount of sodium, potassium and calcium ions in juveniles as well as adults. Exposure to different seawater concentrations probably caused breakdown of the osmoregulatory mechanism in the prawn body. Protein and carbohydrate decreased in both juvenile and adult prawn body, with the decrease in seawater concentrations indicating the utilization of large amounts of protein and carbohydrate from the internal reserve.
Der Einfluß der Komplexierung auf die Kupfertoxizität bei Blaualgen
Authors: Lüderitz V. , Scholz F. , Nicklisch A. , Krause S. 
Published: February 2007

AbstractSome aspects of the influence of copper speciation on toxicity for blue‐green algae are reviewed. The experimental part concentrates on Oscillatoria redekei and Aphanizomenon gracile. The two investigated species produce strong extracellular copper complexing ligands: Oscillatoria redekei in the exponential and stationary growth phase, and Aphanizomenon gracile has a distinct detoxification capacity.The detoxification of copper by synthetic agents was investigated using ethylene‐diamine‐tetraacetic acid. Simultaneous addition of Cu2+ and Na2EDTA gives evidence for a slow complexation reaction. Hence an excess of Na2EDTA is necessary for a fast and complete detoxification of copper.Model calculations are reported to show that the precipitation of copper compounds is not probable under the conditions used.
Die Entfernung von Cadmiumionen aus Spülwässern der galvanischen Industrie mittels Ionenaustausch
Authors: Dobrevski Iv. , Panajotova T. , Dimova‐Todorova M. 
Published: February 2007

AbstractIn laboratory investigations with model waters, the behaviour of selected cation‐exchange resins (Amberlite 200 C, Duolite C‐25, Lewatit S‐100, Wofatit KPS and Wofatit KS‐10) is tested. The usable volume capacity of the resins in the forms of H, Na and NH4 as well as the water content and the total volume capacity after 25 cycles of loading/regeneration are determined. It is recommended to use Amberlite 200 C and Wofatit KS‐10.
Stabilization System for Waste Water Treatment and Use. Part 1. Chemistry
Authors: Svoboda M. , Koubek P. 
Published: February 2007

AbstractThe difficulties arisen in an assimilation pond, as it is called, after 17 years of operation were solved by a stabilization system for the purification of effluents and utilization for fish breeding. It consists of two basins (0.56 and 1.04 ha) and a fish pond (15.58 ha) to which water can flow from a brook by‐passing the system. When the stabilization system had worked for 6 years, it was proved that in the case of the average daily intake of milk of 93,846…118,134 litres, effluents flowing out of the dairy plant amounted to 205.28…228.53 m3, on average. The BOD5 of effluents ranged from 201.33 to 261.73 kg/d and the total solids ranged from 95.5 to 139.3 kg/d on average. The average daily outflow from the pond amounted to 394.7…1567.0 m3 of water with 4.1…23.8 kg of BOD5 and with 29.3…112.4 kg of total solids. The average decrease of the main nutrients and extractable substances ranged from 62.8% (Ca2+) to 100% (NO−3). Only the BOD5 value at the end of the growing season in 1984 (8.4…10.3 mg/l) exceeded three times the standards for the admissible pollution of the receiving stream.
Freshwater Macrophytes as Indicators of Organic Pollution
Authors: Husák Š. , Sládeček V. , Sládečková A. 
Published: February 2007

AbstractThe commonest 118 taxa of freshwater anthophytes and pteridophytes in Czechoslovakia were ranked, on a 10‐point scale of saprobic valency, by their indicative weight (Ii) and by their individual saprobic index (Si).
Neues mathematisches Verfahren zur Charakterisierung unbekannter organischer Vielstoffgemische durch die Adsorptionsanalyse
Authors: Schilling H. , Walther H.‐J. , Worch E. , Burmeister W. 
Published: February 2007

AbstractThe adsorption analysis, a process‐technology‐oriented analytical method, characterizes complex organic multicomponent mixtures with respect to their different adsorbability by a sorbent such as activated carbon. The analytical method is based on the determination of adsorption isotherms and their mathematical interpretation. So far, this interpretation has required the use of a large computer or a time‐consuming computing program, in general. With the BASIC computing program “MAVIAS 10”, on the basis of the IAS theory a mathematical approach has been found which provides sufficient accuracy, demands low expenditure of time and makes the use of a small computer possible.
Seasonal Growth of Eichhornia crassipes (Mart.) and its Possible Impact on the Primary Productivity and Fishery Structure in a Tropical Reservoir
Authors: Sen N. S. , Kapoor V. K. , Gopalkrishna G. 
Published: February 2007

AbstractThe study describes the seasonality in growth and production rate of a warm water hyacinth, Eichhornia crassipes (Mart), in a tropical lake Hatia (23° N 85° E) in India. The summer months were observed to exhibit a log phase of positive accelerating growth only to be terminated all of a sudden with the onset of monsoon. The winter phase of growth, on the other hand, was slower. A decrease in photosynthetic activities of E. crassipes with the increase in existing biomass was also established. The total NPP of E. crassipes alone was approximately 80.522 TJ/a, which was more than 40% of the total phytoplanktonic NPP (182.871 TJ/a) of the lake. The amount of energy processed through the grazing chain as well as detritus chain was found to be of low order as compared to the vastness of the surface area of the lake and the total NPP of the lake. The possible causative factors influencing the primary production have been discussed. Certain means and measures have been suggested to enhance the prevailing poor fishery structure of the lake.
Ecological Studies and Trophic State Evaluation of a Tropical Impoundment in West Africa
Authors: Khan M. A. , Agugo B. A. C. 
Published: February 2007

Weekly base‐line data (September 1983 … March 1984) on plankton community structure, abundance, and primary productivity of a small (A = 3.7 ha, Zm = 16m) water‐supplying reservoir (Kongingiri Dam, alt. 1343 m) in Jos Plateau, Nigeria are presented. Supporting ecological observations include thermal and optical properties, pH, conductivity, dissolved oxygen, alkalinity, chloride and dissolved organic matter.Water characteristics of the exosystem showed varying turbidity (Secchi=1.0−2.8 m), a circumneutral character (pH, x̄=7.1), predominance of bicarbonate (x̄x=0.26 meq/l) system, and moderate ionic composition (x̄x=23 μS/cm).The plankton community was dominated by Bacillariophyceae and Chlorophyceae in population density, and Chlorophyceae in species richness. The important forms were Nitzschia spp. Synedra ulna, Navicula spp. Melosira italica, Pinnularia sp. Staurastrum spp., Cosmarium, Closterium, Eurastrum platycerum, Micrasterias americana, M. crux‐melitensis, Teilingia granulata Desmidium swartzii, Scenedesmus sp. Pediastrum boryanum. The zooplankton community had numerical dominance of rotifers. The principal zooplankton species included Brachionus falcatus, Keratella cochlearis, K. tropica, Trichocerca similis, Pompholyx complanatus, Bosmina longirostris, Ceriodaphnia cornuta, and species of Mesocyclops, Thermocyclops, and copepod nauplii. The ecological characteristics and productivity rates indicate an oligo‐mesotrophic state of the aquatic ecosystem.
Comparison of Antibiotic Resistance and Plasmid Bands between Two Identical Sets of Raw Sewage Enterobacterial Strains
Authors: Astorga A. Fernandez , Fernandez De Aranguiz A. , Umaran A. , Cisterna R. 
Published: February 2007

AbstractA total of 300 enterobacterial strains were collected from raw sewage effluent from the wastewater treatment: a first set of 150 strains collected through 1983 and a second set of 150 identical genera and species composition strains through 1986. The rates of incidence of antibiotic resistance by MICs determinations to eleven betalactamic antibiotics were compared between isolates from both sets. It was determined that there was no increase in the total percentage of resistance (set 1 : 86%0 : set 2 : 90%); however there was an increase in terms of the number and kind of antibiotics that bacteria were resistant to. Screening for the presence of plasmid DNA by alkaline lysis and agarose gel techniques were also compared between antibiotic resistant isolates from both sets. It was found that 27% of antibiotic resistant isolates from set 1 carried plasmid bands and 74% of those from set 2. More of half the plasmid carrying isolates showed multiple bands, and the sizes of classes of the plasmids were higher than 20 MDa in nearly two thirds of plasmid carrying isolates from both sets.
Operational Forecasting of Toxic Waves in Rivers
Authors: Baumert H. , Stoyan G. 
Published: February 2007

AbstractThe paper describes a convection‐diffusion model with dead zones for the non‐stationary transport of water‐soluble toxic materials in rivers. Different numerical schemes for the model equations are analyzed and compared with exact analytical solutions. The different schemes are valuated with special consideration of the practical restrictions of microcomputers. Application results to the river Elbe are shortly reported.
Impact of an Agrochemical on the Nucleic Acid Content of the Gonads of the Freshwater TeleostMystus vittatusduring the Spawning Season
Authors: Pande R. K. , Narain A. S. 
Published: February 2007

AbstractThe freshwater catfish,Mystus vittatus, were exposed for 96 h to the acute toxic dose (LC50—96 h, ie. 550 ppm.) of an agrofertilizer (NPK) during the spawning period (March—June). Their gonads were biochemically analysed for the nucleic acid content. The RNA and DNA contents of stressed fish was found to be lower than that of the control fish in both testes and ovary.
Oxidation Cannel: A Way for Domestic Sewage Treatment in Cuba
Authors: Travieso L. , León M. , Benitez F. , Sánchez E. 
Published: February 2007

AbstractDifferent ways had been successfully used for the removal of organic matter in wastewaters. Conventional treatments are frequently used in Cuba, but it is necessary to find out the best possibilities from the economical point of view. The oxidation channel constitutes a very simple aerobic treatment with high efficiency, and it has never been used in Cuba, that's why the evaluation of the behaviour of this biological reactor is very important in order to establish its advantages in Cuban climatic conditions. Conventional parameters were determined. The obtained results were promising.
Restmetallgehalte isolierter Huminstoffe aus Erde, Moor und Deponie
Authors: Abbt‐Braun G. , Frimmel F. H. 
Published: February 2007

Humic substances isolated from soil, bog lake water and landfill leachates by the XAD‐method (adsorption at pH = 2.0; desorption at pH ≧ 13) contain significant amounts of metals. Data from atomic absorption and atomic emission measurements for the initial aqueous solutions (Cr, Fe, Co, Ni, Cu, Zn, and Cd) are compared with the data for isolated humic samples. The well complexed metals like Cr3+, Fe3+ and Cu2+ are found in relatively large amounts in the isolated humic material. The values are up to some per cent of the metal concentration originally present in the aqueous samples. Most bivalent metals (Co2+, Ni2+, Cd2+) are present in residual amounts of the order of 10−3 of the dissolved metal concentrations in the original solutions. The complexation capacities (CC) for the isolated HS decrease according to their origin: soil > bog lake water > leachates from dumping areas. The systematic error for the determination of CC due to the stronly bound residual metal content is, in general, smaller than 1%.Der experimentelle Teil der vorliegenden Arbeit wurde am Institut für Wasserchemie und Chemische Balneologie der Technischen Universität München durchgeführt.
Bestimmung von Spurenelementen in Gewässern mittels Flotationsspektralphotometrie am Beispiel des Arsens
Authors: Kunze S. , Dietze U. 
Published: February 2007

AbstractHighly sensitive and selective methods for the determination of trace elements in waters and solutions are made possible by the combination of flotation and spectrophotometry (flotation spectrophotometry). The basis for it are multiply charged anion complexes of the analyte, which form sparingly soluble ion association complexes with singly charged basic dye cations in aqueous solution. Intense shaking of the aqueous solution with an organic solvent (having a low dielectric constant) results in the accumulation of these ion association complexes at the interface or on the vessel walls (flotation step). After separating the ion association complexes from the liquid phases, they are dissolved and dissociated in a polar organic solvent and the absorbance of the basic dye ions is measured as a function of the concentration of the analyte. By the example of the trace determination of arsenic in natural water, the possibilities of analytical chemistry by combination of flotation steps and spectrophotometry are demonstrated. According to the arsenic content, its determination can be performed by flotation spectrophotometry with crystal violet (detection limit 50 ng/ml As), by an indirect determination of arsenic via flotation spectrophotometry of molybdenum in the dodecamolybdoarsenic acid (detection limit 1 ng/ml As) or by the combination of collector precipitation of arsenic with zirconium hydroxide followed by froth flotation and flotation spectrophotometry as the determination technique (detection limit 0.05 ng/ml As). The reproducibilities of these variants are indicated and their accuracy is checked by comparison of methods.
Hepato Toxicity of Malathion on the Protein Metabolism in Cyprinus carpio
Authors: Reddy P. Malla , Philip G. H. 
Published: February 2007

AbstractFreshwater fish were exposed to sublethal concentration of commercial grade malathion (50 E. C.) (2 ppm) for 7,15 and 30 days. After each exposure period, certain biochemical parameters were studied. A decrease in total, structural and soluble proteins and an increase in free amino acid and protease activity levels in contrast to protein decrement were observed in 7 and 15 days of exposure, but on 30 days of exposure all the values got nearer to normalcy. The restoration of different protein fractions to normalcy implies that after 15 days of exposure there seems to exist an oscillatory phase in protein turnover towards a more synthetic phase leading to the establishment of recovery and adaptation phenomena.
Veränderungen der Diatomeenflora der Werra unter dem Einfluß des Salzgehaltes
Authors: Ziemann H. 
Published: February 2007

AbstractUnder the influence of the wastewaters of the potash industry the Werra river shows considerably varying salt contents (0.47 … 28.2 g/l Cl−, annual means 4.4 … 11.4 g/l Cl−) in dependence on the hydrological situation. Between 1982 and 1988 a total of 112 taxa of diatoms were observed. Of special interest is the occurrence of Stauroneis constricta (EHRENBERG) CLEVE, which is new for the river Werra. Its spreading upstream was observed. Compared with earlier findings as well as within each annual cycle there are observed clear changes in the species present and in the colonization structures in dependence on the salt content. The close relations between the salt content and the diatom communities are truly expressed by the index of halobic organisms. Diversity indices of 1.048 … 3.259 as well as values of 0.074 … 0.817 for evenness verify the imbalance of the colonization, without, however, revealing a relation to the salt content, except for variations of concentration which may be too sudden.
Role of Inorganic Phosphate in the Phytoplankton Density of Hazaribag Lake, Hazaribag
Authors: Saha T. K. 
Published: February 2007

AbstractPhosphorus is considered to be one of the most important factors in the maintenance of an aquatic eco‐system. The study deals with the relation of available inorganic phosphate in water with phytoplankton abundance. The phytoplankton count ranged between 487 and 1711 indiv./l, while phosphate ranged between 0.18 and 1.23 mg/l. A maximum population of phytoplankton was observed in the month of January 1988 and a minimum observed in April 1988. The correlation between the changes in phosphate concentration and phytoplankton abundance revealed an inverse relationship (r= −0.0773, P>0.05), and the regression is expressed by Y = 370 + 755 (x), indicating its link in the cycle of autotrophs though not significantly.
Community Structure of Zooplankton at River Chambal Near Nagda with Reference to Industrial Pollution
Authors: Kulshrestha S. K. , Adholia U. N. , Bhatnagar A. , Khan A. A. , Baghail M. 
Published: February 2007

AbstractThe community structure of zooplankton was studied in relation to physico‐chemical characteristics of the river Chambal polluted by industrial effluents and domestic sewage near Nagda. Thirtytwo species of zooplankton of five main groups, viz. Protozoa, Rotifera, Cladocera, Copepoda and Ostracoda were observed at pre‐pollution sampling stations. The abundance, distribution, total population, group percentage and species diversity were studied and correlated with pollution‐indicating parameters. Species diversity values indicated a decrease from the sampling station near a pre‐effluent point to an effluent discharge channel and an increase at a post‐effluent discharge point revealing a slight recovery zone. Keratella tropica and Kellicottia sp. were identified as pollution tolerant taxa.
Zur Wassergütebewirtschaftung eines Flußgebietes mit Hilfe kombinierter Wassermenge‐Wassergüte‐Modelle
Authors: Gnauck A. , Büttner M. 
Published: February 2007

AbstractThe basic principle of the combined model applied consists in the coupling of a long‐term management model of the water quantity economy whose stationary conditions are secured by the simulation of long series of measurements on the basis of monthly means of flow. The coupling is performed either by regression models of the water quality (linear and nonlinear single and multiple regressions) especially for conservative, not biochemically convertible substances or with dynamic models of water quality. For the latter case, an example is represented on the basis of a modified STREETER‐PHELPS model for eleven segments of different length of a river in the foothills of low mountain ranges. The coupling of the two models permits statements concerning the river basin management with different types of water utilization being taken into account.
Die Ermittlung von Schwermetallkontaminanten in städtischen Kanalisationsnetzen durch Anwendung der Sielhautanalytik
Authors: Hornig U. , Krause Ch. , Sbieschni G. 
Published: February 2007

AbstractAgriculture having applied a strict standard on the composition of sewage sludges for fertilization, especially on noxious substances such as heavy metals, the sewage control in the sewerage systems is orientated towards the detection of the origin of heavy metals. For this purpose of investigation, the main polluters could be identified and located in two towns from results of the sewer skin investigations in the sewerage systems. A detailed description is given of the arrangement of the measurement networks, the sewer skin sampling technique and the preparation of samples. With the aid of the atomic absorption spectroscopy there were investigated also sewage and digested‐sludge samples for Cu, Cd, Cr, Ni, Pb, Zn. Two groups of sludges having similar composition could be found by means of cluster analysis.
Gas Liquid Chromatographic Analysis of DDT Residues in the Kidney of Labeo rohita
Authors: Verma D. K. 
Published: February 2007

AbstractLaboratory acclimated Labeo rohita, common fresh water edible fish, were exposed to a sublethal concentration (2.5 ppm) of DDT for 2, 4, 8, 16 and 32 days. Residues of three isomers of DDT were estimated in the kidney of Labeo rohita using the gas liquid chromatographic technique. The maximum residues of DDT, DDE and DDD were 1.4327, 0.4172 and 0.2913 ppm, respectively. The total DDT residues concentration was 2.1412 ppm on the final day of the experiment. The tabulated tcalculated t at all intervals.
Toxicity of Copper and Cadmium to Heteropneustes fossilis (BLOCH)
Authors: Gupta A. K. , Rajbanshi V. K. 
Published: February 2007

AbstractStatic bioassay tests were conducted to determine the acute toxic effects of copper, cadmium and their mixtures on Heteropneustes fossilis in two different seasons. Median lethal concentrations (24, 48, 72 and 96 h LC50) revealed that copper is more toxic to fish even at very low concentrations in comparison to cadmium, tested separately or in combination with cadmium. The data indicate that the level of tolerance of the fish to metallic ions tested was temperature specific. Generally, fishes were found to be more susceptible to metallic ions at higher temperatures as revealed by the threshold concentration, MATC and LC50 values. The behavioural changes of the test fishes were also observed in reference to different concentrations of the metallic ions and temperatures.
Mercuric Chloride Induced Inhibition of Acid and Alkaline Phosphatase Activity in the Kidney of Mudskipper, Boleophthalmus dentatus
Authors: Lakshmi R. , Kundu Rahul , Thomas Elizabeth , Mansuri A. P. 
Published: February 2007

AbstractThe present paper deals with the inhibition of the specific activity of the acid and alkaline phosphatases in the kidney tissue of mudskipper Boleophthalmus dentatus, exposed to different sublethal concentrations of mercuric chloride. There was a more or less linear inhibition of the specific activity of both the enzymes with increasing concentration of mercuric chloride as well as exposure time. The inhibition of acid phosphatase could be due to the rupture of lysosomal membrane in the presence of mercury compound, which acts as a labilizing agent. The inhibition of alkaline phosphatase probably caused a breakdown of the membrane transport system.
Modelluntersuchungen zur Denitrifikation im Grundwasser
Authors: Steyer D. , Schwan M. , Schulz F. 
Published: February 2007

AbstractTwo subsurface reactors of 1 m3 volume, filled with fine gravel or coarse sand, are fed with a medium similar to groundwater having a nitrate concentration of 208 mg/l. The retention time of water in the reactor is 400 d. After 30 months the reactor effluent shows a stationary behaviour of the nitrate concentration. Then, the effluent concentration is 90 or 100 mg/l nitrate. The breakthrough curves of nitrate show four pronounced sections: up to the retention time, increase of nitrate to ca. 40 mg/l, a stationary intermediate phase, a further increase of nitrate to the final stationary phase. The stationary intermediate and final phases show 1st‐order reaction constants of 0.0046 d−1 and 0.0019 d−1, respectively, or half‐times of 150 and 330 … 400 d, respectively. The higher reaction constants of the intermediate phase are connected with the bituminous coating of the reactors by the relatively easily degradable organic substance of which reaction is accelerated. With respect to variance analysis the annual minima and maxima of the nitrate turnover show significant differences. This is demonstrated by the temperature dependence of denitrification.