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GC-MS studies to map mechanistic aspects of photolytic decomposition of pesticides
Published February 23, 2008
11-16

Transformation of pesticides in the environment is a highly complex process affected by different factors. Both biological and physical-chemical factors may play a role in the degradation, whose ratio depends on the actual environmental conditions.
Our study aims to reveal specific details of photolytic degradation of pesticides as important... soil contaminants. Significance of these studies is enhanced by the fact that pesticide decomposition may contribute to soil degradation, and have harmful biological effects by degrading to toxic products. The toxicity of the examined pesticides is well known, however very little information is available regarding their natural degradation processes, the quality, structure and biological impact of the degradation products.
The photolytic degradation of frequently applied pesticides of distinctive types (acetochlor – acetanilide, simazine – triazine, chlorpyrifos – organophosphate, carbendazim – benzimidazole) was investigated. A special, immerseable UV-light source was applied in order to carry out photodegradation. The degradation processes were followed by thin layer chromatography (TLC) and mass spectrometry coupled with gas chromatography (GC/MS). EI mass spectrometry was used to identify the degradation species.
Each of the studied pesticides underwent photolytic decomposition, and the detailed mechanism of photolytic transformation was established. At least four degradation species were detected and identified in each case. Loss of alkyl, alkyloxy, amino-alkyl and chloro groups might be regarded as typical decomposition patterns. Deamination occurred at the last stage of decomposition.

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The role and impact of N-Lock (N-stabilizer) to the utilization of N in the main arable crops
Published November 2, 2014
51-55

...5); font-variant-ligatures: normal; font-variant-caps: normal; -webkit-text-stroke-width: 0px; text-decoration-style: initial; text-decoration-color: initial;">The nitrogen stabilizer called N-Lock can be used primarily with solid and liquid urea, UAN and other liquid nitrogen, slurry and manure. In corn it can be applied incorporated before sowing or with row-cultivator or applied with postemergent timing in tank-mix. In postemergent timing need precipitation for long effect. In oil seed rape and autumn cereals the N-Lock should be applied with liquid nitrogen in tank mix late winter or early spring (February-March). The dose rate is 2.5 l/ha. N-Lock increases the yield of maize, winter oil seed rape, winter wheat and winter barley 5-20 %. The yield increasing can be given the thousand grain weight. In case of high doses of nitrogen it can be observed higher yield. The quality parameter also improved, especially the oil content of winter oil seed rape and protein and gluten contents of winter wheat. The use of N-Lock increases the nitrogen retention of soil and reduces nitrate leaching towards the groundwater and the greenhouse effect gas emissions into the atmosphere. The degradation of the applied nitrogen is slowing down and the plant can uptake more nitrogen in long period. The effect of N-Lock the nitrogen is located in the upper soil layer of 0-30 cm and increasing the ammonium nitrogen form. The product can be mixed with herbicide products in main arable crops.

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Study of the biodegradation of slaughterhause feather waste by Bradford method
Published February 25, 2014
77-81

The 15–20% of the by-products of meat- and poultry industry – that unsuitable for human consumption – contains keratin. The slaughter technology of poultry produces large amount of poultry feather with 50–70% moisture content. This means more million tons annually worldwide (Williams et al., 1991; Hegedűs et al., 1998). The keratin con...tent of feather can be difficulty digested, so physical, chemical and/or biological pre-treatment is needed in practice, which has to be set according to the utilization method. The microbiological and enzymatic degradation of feather to soluble protein and amino acids is a very favourable and relatively cheap opportunity to produce valuable products of the resulting feather. Our applied treatments were based on the determination of the most effective method, which is able to follow the biodegradation of waste poultry feather.

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