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Author: P. Marik-Korda
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The heat of reaction of hypobromite with the non-protein nitrogen compounds contained in urine is very high. This fact can be utilized for the determination of these compounds by the inverse DIE method. The DIE method also allows a separate determination of urea based on the specific action of the enzyme urease.

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A thermometric method has been developed for the determination of sulphate after direct or indirect conversion to chromate. The chromate equivalent to sulphate is determined by direct injection enthalpimetry (DIE) using K1 as a reagent, by measuring the temperature change due to the exothermic reaction taking place. The temperature change is proportional to the concentration of sulphate originally present. The method is suitable for the determination of as low as 10−4 M sulphate concentration, which means an increase in sensitivity of about tenfold in comparison with that of the thermometric method based on the reaction of sulphate with barium.

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Authors: György Pokol and P. Marik-Korda
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Organic substances containing double bonds, e.g. allyl alcohol, and different medicaments (quinine, vasalgin), were determined with bromine water by direct injection enthalpimetry. Measurement of the reaction heat or the rate of evolution of heat permits simple and rapid distinction of cis and trans isomers: fumaric and maleic acid, or oleic and elaidinic acid.

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A new equipment based on the inverse-die method

Application of a twin-calorimeter in agricultural industry I

Authors: J. Horváth, P. Prommer and P. Marik-Korda

An automated twin-calorimeter has been developed for the analysis of relatively small sample series which is suitable for the simple and fast analysis of fertilizers. The apparatus was given the name AGROTHERM

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Authors: P. Matušinsky, M. Hanusová, L. Stemberková, P. Mařík, V. Minaříková, L. Tvarůžek, I. Langer and T. Spitzer

The fungus Ramularia collo-cygni is increasingly important as the causal agent of Ramularia leaf spot (RLS). The work aimed to identify gene resources suitable for developing new breeding lines of spring barley with improved resistance. We tested 144 spring barley cultivars at 3 locations in the Czech Republic over 3 years (2009–2011). Only minor and statistically insignificant differences were observed between the individual cultivars in reaction to RLS. No cultivars were observed to have resistance to Ramularia collo-cygni, but significant influence of location and year on the intensity of RLS infection in barley was observed.

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