${session.getAttribute("locale")} 5 The effect of the pesticide, endosulfan, on hepatic cytochrome P-450, liver and gill ultrastructure, and selected haematological parameters of Oreochromis Mossambicus (Peters, 1852) (Pisces : Cichlidae) Wed 12 May 2021 19:21:00 SAST ]]> Electrospun sorbents for solid phase extraction (SPE) and colorimetric detection of pesticides 0. 96), demonstrating the fiber affinity to retain both polar and non-polar compounds opening a possibility to be used as sorbent for sample preparation of different classes of pesticides in water. For the second part of the study simple strategies for colorimetric sensing based on silver nanoparticles and polivinylpyrrolidone capped nanoparticles were developed, respectively for atrazine and chlorpyrifos detection. The limits of detection of the methods were 3.32 and 0.88 mg/L for atrazine and chlorpyrifos respectively. The applicability of the probe in real samples was demonstrated by the recoveries studies of tap water varying from 94 to 104 percent. The versatility of the probe was demonstrated by affording a simple, rapid and selective detection of atrazine and chlorpyrifos in the presence of other pesticides by direct analysis without employing any sample handling steps. Attempt to incorporate the probes in a solid support was achieved by using nylon 6 as solid support polymer proving to be fast and useful for on-site detection.]]> Wed 12 May 2021 17:40:49 SAST ]]> Assessment of organochlorine pesticide residues in fish samples from the Okavango Delta, Botswana Wed 12 May 2021 16:23:00 SAST ]]> Evaluation of manufacturing processes for the production of atrazine 97% could be achieved where the resultant product was well within stipulated product specifications. In view of the results obtained, the following recommendations regarding the synthesis of atrazine in toluene as reaction solvent can be made: · Use a reagent addition sequence that staggers the addition of amine and NaOH in such a manner that amine is added first for a short while, followed by the simultaneous addition of amine and NaOH, and ending with NaOH. Use two reaction vessels in series, one for the IPA addition reaction and one for the MEA addition reaction. In this manner the reaction can be run on a continuous basis since no lag time between amine additions is required. Also, smaller reactors may be used whilst maintaining high production rates. Smaller reactors will improve both temperature control and mixing of reagents.]]> Wed 12 May 2021 15:57:46 SAST ]]> The mode of action of the acyl-diethylamide molluscicides Thu 13 May 2021 06:04:42 SAST ]]> A comparison of different strategies to control pests and diseases in Brassica spp. production in the Western Cape Mon 22 Aug 2022 15:05:57 SAST ]]>