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1

Speciation analysis of chromium in waters

100%

Swietlik R.

Polish Journal of Environmental Studies

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1998

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tom 07

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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

Total content of arsenic, antimony and selenium in groundwater samples from Western Poland

86%

Niedzielski P., Siepak J., Siepak M.

Polish Journal of Environmental Studies

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2001

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tom 10

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nr 5

This paper presents statistical analysis of results of determination of the total content of arsenic, antimony, selenium and microcomponents in 49 samples of groundwater from an area of western Poland (Wielkopolska). The total content of arsenic reached up to 3.00 ng/ml, antimony 1.25 ng/ml, selenium < 0.15 ng/ml, at detection limits of 0.16 ng/ml for As, 0.18 ng/ml for Sb and 0.15 ng/ml for Se. The samples showed low values of the content of the elements considered relative to the values obtained for water samples from other regions. As the groundwater samples were collected from isolated water bearing horizons, the values determined for them could be treated as geogenic.

3

Content of heavy metals in road coarse dust of Warsaw environs

86%

Kozanecka T., Czarnowska K., Jaworska A.

Roczniki Gleboznawcze

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2003

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tom 54

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nr 3

4

The level of non-hydrophobic lipids in pig embryos during cleavage

72%

Romek M., Gajda B., Weber P., Krzysztofowicz E., Smorag Z.

Acta Biologica Cracoviensia. Series Botanica. Supplement

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2008

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tom 50

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nr 1

5

The content of rosmarinic acid, total content of phenolic acids, tannins and flavonoids in lemon balm leaves [Melissae folium]

72%

Modnicki D., Patora J., Klimek B.

Herba Polonica

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2004

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tom 50

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nr 2

A quantitative HPLC analysis of rosmarinic acid has been carried out in different samples of lemon balm leaves. The contents of rosmarinic acid in the samples varied significantly, ranging from 0.9% to 2.79%. Similar differentiation has been found in the content of total phenolic acids (4.08%- -11.93%) determined by means of spectrophotometric method, and also in the content of tannins (3.6%-13.2%) determined using the method with skin powder. The percentages of total flavonoids estimated by spectrophotometric method were within the limit 0.32%-0.44%. The HPLC estimation of rosmarinic acid or spectrophotometric estimation of the total phenolic acids should be regarded for the standardisation of the Melissae folium.

6

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Variation in the total content of phosphorus in potato starch and tubers

72%

Kolodziej Z.

Polish Journal of Food and Nutrition Sciences

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1996

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tom 05

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nr 3

Highly scattered results of the content of total phosphorus in potato tubers and starch were found. The main source of the variation in starch phosphorus content was the potato variety character. The percentage of this source of variation in the total variation of starch phosphorus content was 78%. On the other hand, the total phosphorus content in potato tuber was determined by the environmental conditions. The percentage of variation from the interaction of years and locations in the total variation of tuber content of phosphorus was 84%.

7

Soluble forms of zinc in profiles of selected types of arable soils

58%

Domanska J.

Journal of Elementology

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2009

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tom 14

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nr 1

55-62

The research was carried out on arable soils of the region of Lublin. The aim of the study was to determine the content of Zn extractable in 1 M HCl⋅dm-3 in profiles of selected types of soils and the total content of Zn (measured in aqua regia) in soil samples from the accumulative layer 0-20 cm of the soils. The investigations included 8 morphological types of soils: Rendzic Leptosols (typical rendzinas), Rendzic Leptosols (humic rendzinas), Haplic Phaeozems, Calcaric Cambisols, Haplic Luvisols, Cambic Arenosols, Haplic Podzols, Eutri-Terric Histosols. The content of zinc (Zn) was measured by Atomic Absorption Spectrometry (AAS). In mineral soils the highest content of total Zn was found in rendzinas (48.0-55.8 mg⋅kg-1 DM) and the lowest one appeared in rusty soil and in podzolic soil – about 13 mg Zn⋅kg-1 each, at average 24.5 mg⋅kg-1. Average concentration of available forms of zinc was 5.2 mg Zn⋅kg-1. The amount of this element in soils was from 2.0 mg Zn⋅kg-1 in the level Cca of typical rendzinas to 17.0 mg Zn⋅kg-1 in the accumulative level of peat soil. In most profiles the highest concentration of soluble form of Zn was present in the accumulative layer and was usually decreasing deeper in the profile. The distribution of Zn in profiles was shaped by the biological accumulation of this element in the humus horizon and natural biogeochemical processes.

8

Balancing amino acids based on their total content or intestinal digestibility at two protein levels in feeds for fattening pigs

58%

Wiecek J., Skomial J.

Annals of Animal Science

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2002

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tom 02

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