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601.
Factors influencing uptake of lead(II) by the water hyacinth (Eichhornia Crassipes), were examined. Two phases of uptake were observed for the concentration range investigated (0.01–1000 ppm). The initial, rapid uptake phase of about 4 hours is followed by a slower, near linear phase extending past 24 hours. Stirring the solution enhanced uptake, suggesting that lead removal is in part diffusion limited. In the range of 4–8, pH has little effect on uptake where as outside this range, uptake is reduced. Increased solution volume or rootmass results in more metal being removed by the plant. The presence of strong complexers blocks the initial rapid uptake phase as does the presence of Zn(II), Cd(II), Hg(II), and Fe(III). Strong complexers can also strip a portion of any lead already removed from solution by the plant. 相似文献
602.
In this presentation the results of an environmental study of New Karvali bay, in Kavala Gulf, North Greece, are announced. In the studied bay the main industrial activity is a Factory of Chemical Fertilizers (FCF) and its wastes have been discharged, practically without any treatment, to the sea. The study has shown that the concentrations of phosphates and nitrates in the area around the place of the waste ejection from the factory are relatively high. Other remarkable points of the study are the presence of fluoride anions in higher level than normal and the low concentration of heavy metals (Cu, Pb and Zn). 相似文献
603.
There exist a vast variety of data sources, either manual sources or computerized databases in the field of environmental chemicals. To facilitate the access and to retrieve the information wanted efficiently, we built up two “databanks of data sources”, one called “Databank of Manual Sources (DMAS)” and the other named “Databank of Databases (DADB)”. The set‐up of these databanks is explained and the load status statistics are shown. DMAS has 164 and DADB 106 hits. 相似文献
604.
Male albino rats were fed for 28 days from weaning on diets containing 5% (group 1), 10% (group 2) and 21% (group 3, normal protein) protein as casein. At the end of dietary period, HCH was administered daily for 30 days to investigate the interaction between protein deficiency and pesticide toxicity. The results indicated that rats fed a lower protein diet and HCH had a higher mortality, lower rate of growth, increased liver weight and deposition of the pesticide in blood and tissues in larger amounts. Blood pressure (systolic and diastolic) was significantly increased and the heart rate showed tachycardia in low protein exposed animals. A significant increase of total lipids, cholesterol, triglycirides, free fatty acids in serum and tissues of animals exposed to low protein was observed. A close correlation existed between lipid accumulation and storage of HCH in tissues and dietary protein seemed to play an important role in detoxification. 相似文献
605.
MESIP is a fugacity model which can predict the fate of organic hydrophobic chemicals in aquatic ecosystems. In this paper a short introduction to the mathematical model is presented together with a more detailed listing of the required input data. Comparison of the calculated and measured fate of a fluorescent whitening compound in an artificial outdoor pond is shown 相似文献
606.
The dissipation pattern of the chlorophenoxy herbicides (2,4‐D and 2,4,5‐T) residues in sunflower plants (Helianthus annuus L.) has been studied along with its effect on the changes of plant pigments (chlorophyll‐a,b, total chlorophyll, carotene and anthocyanin), sugar and starch in different parts of the plant. The residues of 2,4‐D and 2,4,5‐T remained for larger period of time (10 days) at higher concentrations than the lower concentration. The concentrations of chlorophylls and carotene were found to be reduced with the application of both 2,4‐D and 2,4,5‐T. But the chlorophyll concentrations were slowly normalized accompanied with the reduction of the herbicide residues. For anthocyanin, there was no significant effect. In case of carbohydrate, the sugar concentration was found to be raised by all doses in leaf and stem. The change in starch content in different plant parts did not follow an uniform pattern at different doses of herbicides. 相似文献
607.
Photodecomposition of the organophosphorus herbicide anilophos [S‐(N‐(4‐chlorophenyl) N‐isopropyl carbaniloyl methyl] 0,0‐dimethyl phosphorodithioate has been studied in methanol. It underwent oxidation, hydrolysis and dimerisation on irradiation with U.V. light and produced a number of photoproducts which were characterised by 1H‐NMR and Mass spectroscopy. 相似文献
608.
The photolysis of Phorate(I) (0,0‐diethyl S‐ethyl thiomethyl phosphordithioate) has been studied as a thin film on a glass surface and in a solution of methanol‐water (60:40) by ultraviolet light (λ > 290 nm). The rate of disappearance of Phorate in the solution show first order Kinetics with a rate constant of 4.9 × 10–5 S –1. The half‐life of (I) exposed on a glass surface is found to be 5 hours. The structure of the major photoproducts were characterised by 1H NMR and mass spectroscopy. 相似文献
609.
The anticancer drugs: adriamycin, farmorubicin and mitomycin C greatly enhance the generation of hydroxyl radicals (HO.) from H2O2 in the presence of Co(II) ions (CoCl2) at pH 7.4 and 8, as measured by the deoxyribose assay. Catalase, hydroxyl radical scavengers (mannitol, cysteine, glutathione, thiourea, lactic dehydrogenase) inhibited the degradation of deoxyribose confirming that HO‐radicals are responsible for the degradation of the carbohydrate. 相似文献
610.
G. Vollmer K. Rasmussen G. Christ O. Nøager J. B. Davis A. van der Wielen 《毒物与环境化学》2013,95(1-4):113-122
The European INventory of Existing commercial Chemical Substances (EINECS) lists all substances which were on the European Community Market between 1 January 1971 and 18 September 1981. Substances on EINECS are known as ‘existing’ substances. The EINECS inventory was drawn up by the European Commission to meet the requirements of article 13 of Directive 79/831/EEC [1]. EINECS was published in the Official Journal of the European Communities in 1990 [2]. This paper describes how individual substances, impurities and mixtures were defined and dealt with when registered for the EINECS inventory. It is the first in a series of such papers. 相似文献