Results 1 - 10 of 2935
Results 1 - 10 of 2935. Search took: 0.028 seconds
|Sort by: date | relevance|
[en] The kinetics of radiolysis processes of 9 chlorous-organic pesticides (hexachlorbenzene, α- HCH, β-HCH, lindan, 4,4'-DDE, 4,4'-DDD, 4,4'-DDT, aldrin and heptachlor) solutions (10 - 1000 ug/l) in hexane at 13,8; 27,7; 67,4 and 105,4 kGy doses was studied and the radiation-chemical yields of conversion processes were calculated in the work. It was identified that the conversion of pesitides of 105,4 kGy dose is 65-95 percent, radiation-chemical yields are (0,009 - 1,247) · 10-3 molecules/100 eV. Increasing of initial concentration leads to the radiation-chemical yields raising. Different radiation-chemical yields observed for various pesticide conversion processes may be due to the variations in their reaction rate with hydrogen atoms and radicals. The difference observed in various isomers (α-HCH, β-HCH and γ-HCH) may be due to the energy of spherical isomeric structures with C - Cl bonds in their molecules
[en] The advantages and drawbacks of coupled chromatographic techniques are discussed on the basis of selected applications of LC-LC and LC-GC in the analysis of pesticide residues applied to environmental biological samples. (author). 18 refs.; 5 figs.; 2 tabs
[en] Transport of bentazone, isoproturon, linuron, metamitron and metalaxyl were studied under three different flows in macrocosms. The aim was to verify the observations from Part I of the accompanying paper, with an increase in column volume and decrease in chemical and hydraulic load. Very limited breakthrough occurred in the macrocosms for all pesticides, except bentazone, at all flows. From batch degradation experiments, it was observed that the lag time of metamitron and linuron decreased drastically in time for all flows, indicating a growth in the pesticide degrading population. This in contrast to isoproturon and metalaxyl, where an increase in lag time could be observed in time for all flows. From the batch degradation experiments, it could be concluded that the influence of flow on the lag time was minimal and that the inoculation of the pesticide-primed soil had a little surplus value on degradation. - Retention and degradation of pesticides in macrocosms liable to different fluxes.
[en] One of the perspective directions for the restoration of contaminated lands is the use of humic-based compounds. The structure of these types of compounds causes to form compounds that dissolve in water combining heavy metals, radionuclides, pesticides and other toxicants. The use of humic-based compounds causes to the land clearing and causes to the increasing of its productivity. During experiments it has been determined that humates have more effective impact with the form of enriched microelements.
[en] The measurement of pesticide and heavy metal contents of river water in upperstream (around some factories), and downstream (housing area), along Cipinang-Sunter river Jakarta, on February-June 1996 had been done. The aim of the measurement was to get information about the influence of factories waste on pesticide and heavy metal contents in the Cipinang river water. Gas and liquid chromatographis were used to measure the pesticide content and X-ray fluorecence spectrometry was used to measure the heavy metals content. Result of the measurements showed that Cipinang river water has contained some organochlorin pesticides, i.e., BHC, a and b endosulfan, dieldrin, pp-DDE, and heavy metals, i.e., Ti, V, Cr, Fe, Ni, Cu, Zn, and Pb
[en] The determination of residues of chlorinated hydrocarbon pesticides is of importance mainly in case of foods of animal origin. However, this determination is made slower or even inhibited by a number of difficulties. Extraction and clean-up procedures are of primary importance even in case of the most polished methods of pesticide analysis problems. The isotopic method was used for testing the mentioned steps. Experiments were carried out with radioactive C-14 isotope. According to the results of control tests, data varying within relatively wide limits have been obtained, depending on the applied method. In each case where the boiling point of the solvent permits, the use of the Kuderna--Danish instrument is advisable. In case of a solvent of higher boiling point a combined method is more expedient. For this purpose a method has been suggested which enables the evaporation of the sample to be carried out without any practical loss of agent, thus the obtained analytical results can be considered as perfectly reliable ones. (P.J.)
[en] This paper reports the case of a family in which three children were presented at Emergency Room (ER) with poisoning after the use of a pesticide at home. Initially, the cases were managed as routine cases of organophosphorus poisoning; however, the death of two children made the health team members realise that the poison's effects were delayed and devastating. Later, the compound was identified as Aluminium Phosphide (ALP), and the life of the last surviving child in the family was saved. (author)
[en] Principles for the development of multi-pesticide methods based on GC determination are outlined. A flow chart gives guidance on how to proceed stepwise in the set-up of analytical methods. (author)
[en] In a laboratory study we investigated the contact and barrier efficacy of different natural substances (wood ash, sawdust, hydrated lime, and diatomaceous earth) against slugs of the genus Arion, an important agricultural pest. Natural substances were tested individually and in combination with each other. The experiment was carried out in plastic petri dishes and in glass insectaria. Moistened tampons and fresh leaves of lettuce were placed into both experimental arenas. The slugs were starved for 48 hours prior to the experiment. Six categories of behaviour were identified for slugs in the presence of the natural substances: (1) slug survived the experiment, (2) slug died during the experiment, (3) slug crossed the barrier, (4) slug did not cross the barrier, (5) slug fed on the lettuce, and (6) slug did not feed on the lettuce. The effect of different treatments (natural substances) was significant. The results of our study have shown that hydrated lime had the best contact efficacy on slugs (the mortality of slugs was 100%), both individually and in combination with other substances. The treatments with hydrated lime also proved to be the most efficient barrier preventing slugs from feeding on lettuce. Hydrated lime shows great potential in Arion control in our investigation; however, further research is needed to investigate the practical value (how to avoid the problem when the substance becomes wet), safety and economics of hydrated lime used in this way. (Author)
[en] As a part of a department of development of various typed organic-inorganic nano-complex using gamma irradiation for nano-leveled pesticide delivery system (PDS), we are investigating for advanced various types of customized nanomaterials development in bioindustry fields. Specially, we described herein, preparation of various types of nano-Ag associated complexes and results are presented