Chemometric analysis of the water purification process data.

The aim of this work was to show usefulness of chemometric analysis in processing of the data describing production of drinking water in the Silesian region of Poland. Water samples have been collected within the period of 1 year and the quality of water was characterized by a number of physical, chemical and microbiological parameters. Principal component analysis (PCA) and STATIS (Structuration des Tableaux A Trois Indices de la Statistique) were employed to obtain the knowledge about the complete water treatment process. PCA makes it possible to uncover seasonal changes influencing the water treatment process. In particular, it was found out that the salt content, hardness and conductivity of water tend to obtain higher levels in winter rather than in summer, and the relatively lower acidity is also to be expected in winter. The sensory quality of water is considerably improved over the consecutive purification steps. Complementary information about the individual technological units of the process is gained with the STATIS approach. The obtained results show that the water produced by the two independent filtering branches of the water plant is of similar quality and the prescribed quality characteristics of drinking water are fulfilled.

[Spectrophotometric determination of scandium,gallium and vanadium in white cabbage leaves]. / Spektrofotometryczne oznaczanie skandu, galu i wanadu w lisciach kapusty bialej.

Scandium, gallium and vanadium contents in plants is on the ppm level, although plants from industrial areas can show higher concentrations of these elements. In Department of Analytical Chemistry of Silesian University there have been elaborated new, sensitive, spectrophotometric methods of determination of scandium, gallium and vanadium using Chrome Azurol S (CAS) and Sterinol (ST). The aim of this study was the application of these methods in analysis of cultivated plants from polluted regions. White cabbage from Upper Silesia was chosen. Because the spectrophotometric methods are not selective, scandium, gallium and vanadium should be preliminary separated from interfering elements. The solvent reaction was applied for the isolation from main and trace components of investigated material. Tienoiltrifluoracetone solution in xylene was used for the extraction of scandium, mesithyloxide for vanadium and n-butyl acetate--for gallium. Interfering and not separated Fe(III) was isolated using the extraction with acetylacetone solution in CHCl3 in the case of scandium and the reduction to Fe(II) by ascorbic acid in the case of gallium and vanadium. Due to influence of Fe(II) on the vanadium determination, KCN was used as a masking agent directly after the reduction. Scandium, gallium and vanadium were determined in 6 independent samples of white cabbage after dry or wet mineralization and contents of these leemnets were found from calibration graphs. Obtain results were checked by the internal standard addition method and Atomic Emission Spectrometry Method (ICP AES). The amounts of gallium and vanadium in white cabbage from Upper Silesia District determined by elaborated methods are in good correlation with a literature data, although the contents of vanadium are on the toxic level. The scandium concentration is higher than in plants from not industrial areas. The standard recovery is satisfactory. The Atomic Emission Spectrometry Method gave comparable results. The proposed the spectrophotometric methods are sensitive, precise and economical too, because they require only small amounts of reagents and simple not expensive apparatus. The methods can be recommended for many laboratories to the analytical control of white cabbage and after adaptation to the other plant material analysis.

[Simultaneous determination of metals in milk by the ICP-AES technique]. / Jednoczesne oznaczanie metali w mleku technika ICP-AES.

The method of the emission atomic spectrometry with an excitation in the inductively coupled plasma (ICP-AES) has wide range of applications due to the possibility of the simultaneous determination of several elements in various materials. This technique allows to carry out a multi-element analysis at relatively low consumption of the sample which is an additional advantage of the method. In this paper we report an application of the ICP-AES method for a direct determination of the element Al, Cu, Fe, Mn, Sn and Zn in the samples of milk. Several types of pressure mineralization (teflon bomb, sealed quartz tubes) as well as the pressureless technique with the use of the H2SO4, HNO3 and H2O2 agents have been studied. The determinations have been carried out with the use of the Spectroflame M sequential spectrometer with the excitation in ICP plasma made by Spectro Analytical Instruments at the Frequency of 27.12 MHz. The milk samples after mineralization have been diluted to the same volume and directly introduced into the ICP plasma with the help of the pneumatic nebulizer of Meinhard type. On the basis of the obtained results it has been concluded that with an application of the aforementioned mineralization method the average values for the determination of the particular elements are comparable. Generally the most "repeatable" results have been obtained for the sample mineralized in the quartz tubes.(ABSTRACT TRUNCATED AT 250 WORDS)

The nutritional education of the public: French experience.

The French Committee for Health Education, a private body exclusively funded by the government, has been responsible since 1975 for putting over the national programme of 'prevention' in the field of health. The Committee's nutritional campaigns are described with particular reference to expectant mothers, the use of a card game as part of general nutrition education, the feeding of children from six to 12, the composition of its technical reports, and future projects.