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1,3-propanediol (1,3-PD) is the important product used in chemical industry. Microbiological synthesis of 1,3-PD from crude glycerol is a good solution, both from an economic and environmental point of view. The aim of this work was to investigate the ef­fect of raw material (pure and crude glycerol) on the efficiency of the synthesis of 1,3-PD by the bacteria Clostridium butyricum DSP1 and Clostridium butyricum DO14 isolated from the samples taken from natural environment. Two strains of C. butyricum were simul­taneously investigated. The obtained results showed that the concentration of 1,3-PD was slightly lower in the case of crude glycerol than in pure glycerol, for both strains. Moreover, waste glycerol was not completely utilized.
Despite legal regulations limiting emissions of persistent organic pollutants (POPs), including dioxins, to the environment, they still constitute a significant component of environmental contamination. They are released in large amounts during various processes of combustion in industry, the management of refuse materials and also as a result of situations that are partially beyond our control, like fires, explosions and damage in chemical industries. Observations originating from various studies prove that exposure to dioxins results in multiple toxic effects on humans and experimental animals. Among the various disorders caused by dioxins are abnormalities in dentition. The effects of dioxin may last long after exposure.
A novel modified Fenton process using heterogeneous catalyst (swarf) was developed to catalyze the oxidation reaction of azo dye Acid Red 18. It was found that swarf could be used to replace iron salts as a catalyst for the Fenton reaction. The examined continuous Fenton process proved to be very efficient for decolorization of simulated wastewater containing 100 mg/dm³ Acid Red 18. Performance of the Fenton reactor and regeneration method of the catalyst was discussed. The simplified mechanism of hydroxyl radical production in the presence of swarf as a catalyst also was proposed.
Określono działanie drażniące i uczulające acetoacetonianodikarbonylorodu i trifenylofosfiny - składników katalizatora rodowego.
This paper characterises S-SO4 concentration in the surface (0-20 cm) layers of the agricultural soils in Poland (45242 soil samples) and in the Lublin region (3648 soil samples). Mineral soils in Poland contain, on average, 1.79 mg of S-SO4/100 g of soil. In the Lublin region, it is 1.65 of S-S-O4/100 g of soil. In the whole of the country, 83.2% of the agricultural soils have natural (00 +10) levels of S-SO4; this includes the areas with very low (00) concentrations (58.1% of the agricultural land) as well as elevated (10) concentrations (25.1% of the agricultural land). Soils polluted with sulphur (20+30) make up 16.8% of the agricultural land. This includes weak (20) and heavy (30) pollution - 13.1 and 3.7%, respectively. In the Lublin region, 88.5% of the agricultural soils have natural (00+l0) levels of S-SO4 . This includes the areas with low (00) concentration (64% of the agricultural land) as well as the areas with elevated (1°) concentration (24.5% of the agricultural land). Soils polluted with sulphur (20+30) make up 11.5% of the agricultural land, including weakly (2°) polluted soils (8.7%) and heavily polluted (30) soils (2.8%).
Male reproductive organs are extremely sensitive to the negative influence of toxic environmental factors as well as drugs, and until now not many attempts have been made at studying the detoxication enzymes and the relationship between the activity of those enzymes and spermatozoa fertility. In the present work we studied cytosolic glutathione-S-transferases (GST, EC 2.5.1.18) from different parts (head, corpus and tail) of bull and boar epididymis. We isolated two molecular forms of GST from each part of epididymis, characterized their biochemical properties and examined the mechanism of the catalyzed reaction. On the basis of their substrate specificity and isoelectric point, the isoforms were found to belong to the near neutral GST class mi. All examined GST forms exhibited higher affinity towards GSH than towards 1-chloro-2,4-dinitrobenzene (CDNB) and bull epididymis GST forms showed biphasic Lineweaver-Burk double reciprocal curves in the presence of GSH as a variable substrate. Boar epididymis anionic GST had the -SH groups both in the GSH and the CDNB binding place, whereas the cationic GST form arginine residues in the CDNB binding place. Bull epididymis GST forms contained neither thiol nor arginine residues essential for catalytic activity.
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