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871.
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A greenhouse study was conducted to evaluate the response of herbaceous mimosa (Mimosa strigillosa) to six levels of cyclic soil moisture stresses in a 17-week period. The results showed that the cultivar continued to grow and the biomass continued to increase even when the soil moisture stress was as high as at the wilting point (1500 Kpa). Also, transpiration recovery rate was quick and values of root/shoot ratio were high when the plant was subject to the cyclic moisture stress condition. All these characteristics, along with strong rooting and spreading ability, suggest this legume as a promising drought hardiness species for reclamation purposes.  相似文献   
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New data on Se-deficiency in Yugoslavia are presented. The results include Se contents of soils, cereal crops and garlic grown in the investigated soils, and human serum and scalp hair from several towns and regions in this country. All data indicate a serious Se-deficiency. Analyses of human tissues show a very low Se-status of the Yugoslav population. In some regions, Se contents of garlic, grains and human serum and hair are approaching those in the low-selenium zone in China. It is assumed that the very low Se-status of the human population could be a risk factor for the endemic nephropathy and the urinary tract tumours in endemic areas.Originally presented at the 8th Meeting of the Society for Environmental Geochemistry and Health, University of Reading, England (April 1990) (Volume 13, No.2 (1991) of this journal) and subsequently submitted as a volunteered paper.  相似文献   
876.
The subject of investigation was exhausted cooling oil-emulsions coming from copper wire drawing. The summary content of the organic substances in emulsions expressed as COD, ranged from 200 to 300 gO2/dm3. The total amount of copper was about 7 g/dm3. The suggested method of treatment was based on separation of emulsion, thermocatalytic oxidation of the oil phase and electrochemical reduction of copper. The method allows oxidation of 99% organic substances in an autothermic way and over 90% recovery of metallic copper contained in emulsion with energy consumption at 2.2 kWh/kg.  相似文献   
877.
The contentration of lead, cadmium, and mercury in 134 samples of imported fruits and vegetables marketed in Kuwait were determined using an atomic absorption spectrophotometer with a graphite furnace and the cold vapor technique. Results obtained showed that the concentration of these metal ions in most cases did not exceed the maximum permissible concentration of metals in fresh fruits and vegetables as restricted by some countries. Only a few samples of fruits and vegetables contained levels of mercury, cadmium, and lead which exceeded these maximum permissible levels.  相似文献   
878.
A one step extraction and cleanup procedure for determining endosulfan in fish was investigated. Minced Fish was mixed with trisodium citrate, disodium hydrogen orthophosphate and sodium sulphate into a dry powdery mixture, which was eluted through silicic acid and alumina with a mixture of dichloromethane and hexane. The eluate was concentrated and chromatographed on GLC using an EC detector without further cleanup. Three species of fresh water fish exposed to 0.7-16 micrograms/litre-1 technical grade endosulfan in tanks for various periods of time were found to concentrate both alpha and beta endosulfan and metabolise them to sulfate, diol, ether and lactone. Fish collected from Gwydir River in the cotton growing area in summer (Dec. 1986-Feb. 1987) were found to contain endosulfan residues suggesting endosulfan is quite stable in the environment and can cause residues.  相似文献   
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