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1

Speciation analysis of chromium in waters

100%
Swietlik R.
Polish Journal of Environmental Studies
|
1998
|
tom 07
|
nr 5
The total content of chromium in natural waters does not generally exceed several mg/l. Thus, it is obvious that various forms of chromium will occur at the levels of tenths or hundredths of mg/l. Their determination requires the application of a sufficiently sensitive method, but an important role to play has its specificity in the case of chemical individuals or selectivity in regard to speciation of a group of compounds, e.g. valency states or organic chromium complexes. Generally, however, there is a lack of specific and selective methods, and the concentrations of various forms of the analyte occur often at the level of detection limits of even such sensitive techniques as atomic absorption spectrometry. This paper presents a review of currently available analytical possibilities of chromium speciation investigations in natural water samples. Analytical procedure schemes enabling "total speciation analysis" have been discussed in some detail. A large group of methods used in the speciation analysis of chromium(III) and chromium(VI), both in off-line and on-line mode, has also been discussed.
2

Empirical formulae for efficiency of DOM removal by adsorption determined on the basis of bench-scale results

86%
Szlachta M., Adamski W.
Polish Journal of Environmental Studies
|
2009
|
tom 18
|
nr 3
481-486
3
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Magnetic treatment of irrigation water

86%
Rokhinson E. E., Baskin V. V.
Zeszyty Problemowe Postępów Nauk Rolniczych
|
1996
|
tom 436
Natural water used for washing, out and irrigation presents an open nonstationary heterogeneous multicomponent system closely connected with the atmosphere. One should consider such water as a gas-liquid solution where there is a water-gas-solid inclusion equilibrium. When passing the solution through nonhomogeneous magnetic fields several irreversible hydrophysical and hydrochemical processes arise in it which significantly change the natural water properties. One of the most important effects observed in experiments is increasing the number of crystal particles of CaCO₃ which causes reducing the supersaturation of natural water with CaCO₃, shifting the carbonic acid equilibrium and increasing the CO₂ content in water. This water penetrates better through alkaline carbonate soils. The application of the magnetic treaters for leaching saline soil and irrigation treatment allows to diminish the water consumption, to decrease significantly the soil salinization, to enhance moisture supply of plants and to increase the crop yield. The method can positively influence on preservation of water resources of the planet.
4

Evaluation of selected polarographic techniques for the determination of uranium in sea and inland waters

86%
Szefer P.
Oceanologia
|
1981
|
tom 13
5

Treatment of natural waters using capillary membranes

86%
Konieczny K.
Polish Journal of Environmental Studies
|
1998
|
tom 07
|
nr 4
Among all the technologies of water treatment, membrane technology appears to be the most promising. The major advantage of this technology is its ability to produce water with a constant and well adjusted quality. Moreover, membranes remove a wide range of substances, ranging from particles to ions, including bacteria and viruses, and they can operate without any chemical addition to raw water. The paper presents the results of investigations concerning the application of capillary microfiltration (polypropylene) and ultrafiltration (polysulfone) membranes for the purpose of treatment of natural water. The effectiveness of ultra- and microfiltration was assessed by volumetric measurements of the permeate flux as well as by microbiological and physico-chemical analyses.
6

Survival of Escherichia coli in freshwater

86%
Wcislo R., Chrost R. J.
Polish Journal of Environmental Studies
|
2000
|
tom 09
|
nr 3
Experiments on the survival of Escherichia coli were conducted in the water of man-made Zegrzynski Reservoir. The aim of this study was to evaluate how selected biocenotic factors (predation, coliphage infection, presence of autochthonic microflora and nutrient conditions) affect this process. We observed residual living cells of E. coli up to about thirty days of the investigation. We found that the major factor that was responsible for mortality of E. coli was microflagellate grazing and exposure to an aquatic environment. Size-selective preferences of microflagellates toward E. coli cells were observed. No visible effect of bacteriophages on the survival of E. coli was detected. Better nutritional condition and the presence of native heterotrophic microflora significantly prolonged the survival time of E. coli in the studied environment.
7

Modelling of the membrane filtration process of natural waters

86%
Konieczny K., Rafa J.
Polish Journal of Environmental Studies
|
2000
|
tom 09
|
nr 1
This work presents the verification of the model of the membrane filtration process of natural waters for non-stationary filtration flux J=f(t), as well as the results of tests involving the filtration process of the said model in constant pressure conditions. Also, the characteristic time of permeate flux decay was determined, and the mechanisms reducing the efficiency of filtration process were analyzed.
8

The contents and variability of TOC, POC and DOC concentration in natural waters

86%
Baralkiewicz D., Siepak J.
Polish Journal of Environmental Studies
|
1994
|
tom 03
|
nr 2
This paper reports the results of studies of organic carbon concentrations (TOC, DOC and POC) in samples of natural water. The material studied came from 11 lakes in Wielkopolski National Park, from the Vistula and Warta rivers, 20 public wells situated in rural areas of the Wielkopolska region, and mineral water intakes located at different depths. In the case of surface waters, changes in DOC and POC were recorded for one year. The results were compared with data on natural waters available in literature.
9
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Natural mineral bottled waters available on the Polish market as a source of minerals for the consumers. Part 1. Calcium and magnesium

72%
Gatarska A., Tonska E., Ciborska J.
Roczniki Państwowego Zakładu Higieny
|
2016
|
tom 67
|
nr 1
Background. Natural mineral waters may be an essential source of calcium, magnesium and other minerals. In bottled waters, minerals occur in an ionized form which is very well digestible. However, the concentration of minerals in underground waters (which constitute the material for the production of bottled waters) varies. In view of the above, the type of water consumed is essential. Objective. The aim of the study was to estimate the calcium and magnesium contents in products available on the market and to evaluate calcium and magnesium consumption with natural mineral water by different consumer groups with an assumed volume of the consumed product. Material and methods. These represented forty different brands of natural mineral available waters on Polish market. These waters were produced in Poland or other European countries. Among the studied products, about 30% of the waters were imported from Lithuania, Latvia, Czech Republic, France, Italy and Germany. The content of calcium and magnesium in mineral waters was determined using flame atomic absorption spectrometry in an acetylene-air flame. Further determinations were carried out using atomic absorption spectrometer - ICE 3000 SERIES-THERMO-England, equipped with a GLITE data station, background correction (a deuterium lamp) as well as other cathode lamps. Results. Over half of the analysed natural mineral waters were medium-mineralized. The natural mineral waters available on the market can be characterized by a varied content of calcium and magnesium and a high degree of product mineralization does not guarantee significant amounts of these components. Among the natural mineral waters available on the market, only a few feature the optimum calcium-magnesium proportion (2:1). Considering the mineralization degree of the studied products, it can be stated that the largest percentage of products with significant calcium and magnesium contents can be found in the high-mineralized water group. Conclusions. For some natural mineral waters, the consumption of 1 litre daily may ensure the recommended intake levels of calcium and magnesium in some consumer groups to a considerable degree. For 1-3 -year-old children it is recommended to consume less than 1 litre daily of natural mineral waters containing an excess of 700 mg of calcium and 80 mg of magnesium in 1 litre.
10

On the cccurence of uranium and thorium in the biosphere of natural waters. Part II. Uranium and thorium in corals, molluscs and fish

72%
Szefer P., Ostrowski S.
Oceanologia
|
1981
|
tom 13
11
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Determination of barium in natural waters by ICP-OES technique. Part II: Assessment of human exposure to barium in bottled mineral and spring waters produced in Poland

72%
Garbos S., Swiecicka D.
Roczniki Państwowego Zakładu Higieny
|
2013
|
tom 64
|
nr 2
Background. A method of the classification of natural mineral and spring waters and maximum admissible concentration (MAC) levels of metals present in such types of waters are regulated by Commission Directive 2003/40/EC, Directive 2009/54/EC of the European Parliament and of the Council and Ordinance of Minister of Health of 30 March 2011 on the natural mineral waters, spring waters and potable waters. MAC of barium in natural mineral and spring waters was set at 1.0 mg/l, while World Health Organization determined the Ba guideline value in water intended for human consumption at the level of 0.7 mg/l. Objective. The aims of the study were: the determination of barium in natural mineral and spring waters (carbonated, noncarbonated and medium-carbonated waters) produced and bottled on the area of Poland, and assessment of human exposure to this metal presents in the above-mentioned types of waters. Material and method. The study concerning barium determinations in 23 types of bottled natural mineral waters and 15 types of bottled spring waters (bought in Polish retail outlets) was conducted in 2010. The analyses were performed by validated method of determination of barium in water based on inductively coupled plasma optical emission spectrometry, using modern internal quality control scheme. Results. Concentrations of barium determined in natural mineral and spring waters were in the ranges from 0.0136 mg/l to 1.12 mg/l and from 0.0044 mg/l to 0.43 mg/l, respectively. Only in the single case of natural mineral water the concentration of barium (1.12 mg/l), exceeded above-mentioned MAC for this metal, which is obligatory in Poland and the European Union - 1.0 mg/l. The long-term monitoring of barium concentration in another natural mineral water (2006 - 2010), in which incidental exceeding MAC was observed in 2006, was conducted. All measured barium concentrations in this water were lower than 1.0 mg/l and therefore, it is possible to state that the proper method of mixing waters taken from six independent groundwater intakes applied during production is actually used. The estimated Hazard Quotient indices were in the ranges: 0.0019 - 0.16 (natural mineral waters) and 0.00063 - 0.061 (natural spring waters), respectively. Conclusions. The natural mineral waters are usually characterized by higher Ba concentrations than those observed in the cases of natural spring waters. The presence of a high concentration of HCO3 - in such types of natural waters ensures the existence of Ba2+ in solution as Ba(HCO3)2, which is a highly soluble salt. Taking into account the concentrations of barium determined in above-mentioned waters and the available toxicological data for this metal no long-term risk for human health could be expected (estimated Hazard Quotient indices ≤ 0.16).
12

On the occurence of uranium and thorium in the biosphere of natural waters. Part I. Uranium and thorium in plankton and inherent plants

72%
Szefer P., Ostrowski S.
Oceanologia
|
1981
|
tom 13
13
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Wplyw wybranych adiuwantow na trwalosc atrazyny w wodach naturalnych

72%
Wlodarczyk M., Wybieralski J., Praczyk T., Galczynska M., Lewandowska L.
Zeszyty Problemowe Postępów Nauk Rolniczych
|
2006
|
tom 515
423-430
W pracy badano wpływ adiuwantów na szybkość degradacji atrazyny (substancji modelowej) w wodach, w warunkach laboratoryjnych. Wykazano, że degradacja atrazyny w wodzie destylowanej zachodziła wolniej niż w wodach naturalnych. Nie stwierdzono znaczącego wpływu adiuwantów, na szybkość degradacji atrazyny w wodzie destylowanej (wyjątek Adpros 85 SL). Odnotowano istotny wzrost szybkości degradacji atrazyny w wyniku zastosowania adiuwantów olejowych (Adpros 85 SL, Olejan 85 EC) natomiast spadek w przypadku zastosowania surfaktantu Break-Thru S 240. Czas połowicznego zaniku atrazyny w wodzie, w obecności adiuwantów wyniósł od 200 do 59 dni.
14
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Snizhenie agregativnojj ustojjchivosti kolloidnojj primesi prirodnykh vod aktivirovannym rastvorom koaguljanta sul'fata aljuminija

72%
Ehpojan S., Dushkin S.
Motrol. Motoryzacja i Energetyka Rolnictwa
|
2013
|
tom 15
|
nr 5
15

Optical classifications of the seas in relation to phytoplankton characteristics

72%
Wozniak B., Pelevin V. N.
Oceanologia
|
1991
|
tom 31
16
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Bottled waters as a source of minerals

72%
Gatarska A.
Nauki Inżynierskie i Technologie
|
2013
|
nr 1(8)
The aim of the study was to determine the content of minerals in bottled waters (natural mineral water and spring water) and compare the results with information declared by the manufacturers. Nineteen types of bottled natural waters available on the local market were examined with flame atomic absorption spectrometry. The results of analyses of bottled waters available on the market showed significant differences in the concentration of the minerals. These differences depended not only on type of the water but was found within one type of product. In addition, the concentrations of the cations under study differed significantly from the values declared by the manufacturers. The biggest discrepancy was detected in the concentration of magnesium ions; in this case, the actual content was incompatible with the declared by the manufacturer one in about 80% of tested samples. These results give also valuable information for consumers, which should be conscious that not every bottled water, it is alike valuable source minerals.
17

Verification of measurement capabilities of flame atomic spectrometry for the determination of sodium, potassium, magnesium, and calcium in natural fresh water. Part I. Comparison of recommended methods

72%
Jonca Z., Lewandowski W.
Polish Journal of Environmental Studies
|
2004
|
tom 13
|
nr 3
Current Polish Standard methods for the determination of sodium, potassium, magnesium, and calcium in natural fresh water were compared with other official standards, mostly from the U.S. (ASTM, USEPA, USGS), regarding recommended top concentrations of measured elements in measured solutions and methods of regulating the sensitivity of measurements. Some of the disadvantageous limitations of conditions and methods of performing the spectrometric measurements that exist in Polish Standards were shown.
18

Fly ash and slug mixture from heat and power generating plant as environmentally friendly industrial waste

72%
Zerbe J., Siepak J., Elbanowska H.
Polish Journal of Environmental Studies
|
2001
|
tom 10
|
nr 2
Mixtures of fly ash and slugs were subjected to laboratory tests in order to estimate their influence on natural water and soil condition in order to check their possible application towards for recultivaton or landfilling. The chemical composition of the mixtures and their extracts obtained with solutions of sulphuric acid (pH 2 or 4) as eluent (simulating acid rain) were determined. Assuming the criteria to be met by drinking water specified by the European Union and WHO documents, it was established that the heavy metals content in the fly ash and slug mixtures is not expected to have a negative effect on underground water.
19

Mercury cycle in the aquatic environment: a review

72%
Kozlowska K.
Polish Journal of Environmental Studies
|
1995
|
tom 04
|
nr 4
The purpose of the present review is to conduct a detailed description of mercury cycling and accumulation within the freshwater ecosystem and to identify natural chemical and biological processes which affect mercury availability in the aquatic environment.
20
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The significance of dissolved organic matter photodegradation as a source of ammonium in natural waters

72%
Grzybowski W.
Oceanologia
|
2002
|
tom 44
|
nr 3
Samples of sea, river and pond water of different absorbance were exposed to artificial radiation resembling sunlight in the UV range. A statistically significant increase in ammonium concentration was detected in pond water of the highest absorbance after 5 h of irradiation. In sea and river water a corresponding increase (< 0.5 μM) was recorded after an exposure time of 25 hours. The bulk characteristics of the analysed samples were insufficient to explain the observed differences.
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