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981.
M T Akay A Elcüman M Nurcan D Kolankaya G Yilmazoglu 《Journal of environmental science and health. Part. B》1992,27(4):325-340
Lentil grains treated with malathion and stored under laboratory conditions for 12 months formed bound residues. Bioavailability and the effects of lentil-bound residues of malathion in rats were studied. The amount of bound residues in lentils treated with 14C-malathion at 10 ppm and 50 ppm gradually increased to 9.52% and 13.01% of the initially applied doses after 12 months. When rats were fed these 14C-bound residues, radioactivity excreted in urine accounted for 34.49% of the administered dose. In feces, 26.15% of given dose was methanol-extractable while 18.67% was determined as nonextractable. Various tissues including liver, kidney, fat and lungs contained 8.93% while radioactivity in expired air (14CO2) was low (1.51%). The results indicate that lentil-bound malathion residues are highly bioavailable to rats. Analysis of the lentil material containing bound residues indicated that the main compound was malathion. Lentil-bound malathion residues were administered to albino rats at 0.95 and 6.51 ppm in the feed for 3 months. Body weights were determined during and at the end of the experiment. Terminal organ weights were also determined and a number of blood chemistry parameters were examined. A significant reduction in serum cholinesterase activity and an increase in blood urea nitrogen and in white cell count suggest a toxocological potential of the bound residues. 相似文献
982.
983.
984.
The consideration of time in environmental research allows new insights into the fundamentals of environmental research and new pathways for perceiving and answering questions which might arise in environmental research. In order to take this all into account, one must realize that ecological systems have a history and that both the spatial aspects and the chronological expansion of these systems must be taken into consideration. Considering temporalities, rhythms and time scales as well as their interdependencies in environmental research and environmental protection enables us to obtain a better understanding. The significance of relationships and functions in ecological systems can be perceived better as well. The impact of pollutants as well as the outcome of human actions in ecology, and in economics and politics, is consequently mandatory for not only a spatial, but also for the involved temporal scales. 相似文献
985.
986.
The results of a study of the photolytic degradation of mono- and difluorophenols as a function of oxidation agent and temperature are reported. The effects of the position of fluorine are discussed. Fluorinated aromatic compounds have been mineralized to CO2, fluoride, acetate and formate by irradiation (l=254nm) over various intermediate steps. The degradation of fluorophenols apparently followed first-order kinetics. A proposed degradation pathway for the photolytic oxidation of fluorophenols is presented. A complete mineralization as generally proposed in the literature cannot be supported by our results. 相似文献
987.
988.
989.
Environment, Development and Sustainability - The depletion of fossil fuels and the fact that fossil fuels pollute the environment accelerated the trend toward environmentally friendly energy... 相似文献
990.
Athlua B. Attygalle Karla Jessen Hans-Jürgen Bestmann Alfred Buschinger Ulrich Maschwitz 《Chemoecology》1996,7(1):8-12
Summary Gas chromatographic analyses of volatizable material from gaster intersegmental complex glands ofP. tridentata revealed the presence of linoleic acid, palmitic acid, methyl oleate, and several long-chain hydrocarbons as major constituents, which form an oily fluid mixture. The nest relocation communication ofP. tridentata is tandem running. Tandem following is mediated by pheromones as demonstrated by dummy experiments with isolated gasters and thoraces and with glass balls. The secretions of all gaster complex glands, as well as hind gut contents and metapleural gland secretions, were unable to evoke tandem following. Morphology and position of the glands, lack of pheromonal function, oily properties, low volatility, and lack of antibiotic effects of these secretions strongly suggest a function as lubricants for the ants' gastral segments. 相似文献