Comparing the Performance of Organic Solvent Nanofiltration Membranes in Non-Polar Solvents

Organic solvent nanofiltration (OSN) is gradually expanding from academic research to industrial implementation. The need for membranes with low and sharp molecular weight cutoffs that are able to operate under aggressive OSN conditions is increasing. However, the lack of comparable and uniform performance data frustrates the screening and membrane selection for processes. Here, a collaboration is presented between several academic and industrial partners analyzing the separation performance of 10 different membranes using three model process mixtures. Membrane materials range from classic polymeric and thin film composites (TFCs) to hybrid ceramic types. The model solutions were chosen to mimic cases relevant to today's industrial use: relatively low molar mass solutes (330–550 Da) in n-heptane, toluene, and anisole

Influence of killing agents and water on the capture of six Coleoptera species in probe traps

The introduction of propylene glycol, DDVP and water inside perforated probe traps was evaluated on the basis of their effectiveness in trapping adults of six species of Coleoptera infesting stored cereals. Adults of Sitophilus oryzae, Tribolium castaneum, Cryptolestes ferrugineus, Tenebroides mauritanicus, Rhyzopertha dominica and Oryzaephilus surinamensis were placed in plastic cylindrical bins each containing 14 kg of wheat. One probe trap was then introduced into each container and the adults trapped were counted 72 h later. Experiments were conducted at two population densities, of 30 adults (approx. one insect per 0.5 kg of wheat) and 90 adults (approx. three adults per 0.5 kg of wheat) of each species per container. The highest percentage of adults trapped was observed for C. ferrugineus and T. castaneum, and the lowest for R. dominica and S. oryzae. No significant differences in number of adults captured (% of the total number of adults) was noted between the two population density levels. At the lower density, the presence of killing agents in the traps did not increase the captures significantly; on the other hand, at the higher density, the killing agents helped to increase significantly the catches of S. oryzae, T castaneum, T mauritanicus and O. surinamensis, as compared with the catches in the control traps. No significant differences were noted for C. ferrugineus and R. dominica

Distribution and migration of insects and mites in flat storage containing wheat

Studies were conducted in a flat storeroom in central Greece, filled with approx., 90 tons of wheat, in order to evaluate insect and mite species abundance, and changes in population density and distribution among sampling units and locations. The surface of the grain bulk wag divided into two sampling zones: the central and the peripheral (edge). At 10-day intervals, five wheat samples were taken from the central zone and eight from the peripheral zone, with a non-partitioned grain trier (1.6-m length, 250-g capacity). Fifteen insect species and 12 mite taxa were found during the sampling period, (June 1999-Feb. 2000). The most abundant insect species were Sitophilus oryzae (L.), Cryptolestes ferriegineus (Stephens), Tribolium castaneum (Herbst) and Latheticus oryzae Waterhouse; the most abundant mite species were Acarus siro L., Lepidoglyphus destructor (Shrank), and the predators Blattisocius tarsalis (Berlese) and B. keegani Fox, Grain temperature decreased during the storage period, more slowly in the central than peripheral zone; grain moisture content increased. The highest population densities for both insects and mites were recorded during September and October. The most numerous species of insects and mites showed an aggregated spatial pattern, as indicated by Iwao's Patchiness Regression