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11.
Concentrations of 222Rn were measured in ancient copper mines which exploited the Faynan Orefield in the South-Western Jordanian Desert. The concentrations of radon gas detected indicate that the ancient metal workers would have been exposed to a significant health risk and indicate that any future attempt to exploit the copper ores must deal with the hazard identified. Seasonal variations in radon concentrations are noted and these are linked to the ventilation of the mines. These modern data are used to explore the differential exposure to radon and the health of ancient mining communities.  相似文献   
12.
We have studied the process of a prolonged dynamic filtration on activated carbon in two biosorption systems — without preoxidation treatment of the initial matter and after ozonization. It has been shown that given the uniform load on activated carbon terms of the organic matter the efficiency of the biosorption process after preozonization is 2.3 times as small compared with that that without pretreatment, which correlates with the change of adsorption free energy.  相似文献   
13.
Russian Electrical Engineering - The cells of homogeneous digital structures designed for multioperation process diagnostics are considered in the form of graphic models. Digital circuits and...  相似文献   
14.
Kornilov  G. P.  Abdulveleev  I. R.  Gazizova  O. V.  Koptsev  L. A. 《Metallurgist》2021,65(7-8):783-793
Metallurgist - The article provides a brief assessment of the current state of power supply units at metallurgical plants and prospects for their future development. The principal power-supply...  相似文献   
15.
Farisov  R. D.  Ioffe  M. A.  Leushin  I. O. 《Metallurgist》2021,65(7-8):910-918
Metallurgist - The well-known technologies of remelting iron shavings lead to significant (30%) losses of metal. An electroslag smelting furnace with graphite electrodes is proposed for remelting...  相似文献   
16.
Russian Journal of Non-Ferrous Metals - Experimental studies have been carried out with theoretical calculations of wave synthesis in the Ni–Al–Cu system using a mathematical model....  相似文献   
17.
Powder Metallurgy and Metal Ceramics - The phase composition, type II microstresses, and coherent scattering domains (CSDs) of multicomponent (medium- and high-entropy) bcc solid solutions with an...  相似文献   
18.
Powder Metallurgy and Metal Ceramics - Fuel cells are today among the most efficient and environmentally friendly devices for the production of electricity. They are developing rapidly and are...  相似文献   
19.
Responses to hydrocarbon stress of four tropical plants Panicum maximum, Zea mays, Centrosema sp. and Pueraria sp. grown in crude oil contaminated soils (1%, 5% and 10% w/w) were evaluated in a green house. Plants’ percentage survival, shoot heights, biomass development, and phytotoxicity susceptibility were used as indicators of growth, stress response and hydrocarbon tolerance. Relative to control, shoot heights and biomass of plants reduced with increasing hydrocarbon concentration, but 1% w/w oil-in-soil, stimulated shoot heights (5.9% and 6.4%) and weights (21.9% and 2.3%) in P. maximum and Centrosema sp. respectively. P. maximum tolerated the contaminant stress with biomass yields of 113% and 57% of control respectively in 1% and 10% w/w oil-in-soil. All the plants had 100% survival in 1% w/w, but considerably reduced survival in 10% w/w oil-in-soil. These results show that P. maximum has great potential for phytoremediation of petroleum contaminated soil.  相似文献   
20.
This communication deals with an aspect of occupational hygiene in a factory producing granite cutting diamond wheels by sintering, in moulds, of fine cobalt powder. The factory has been studied between 1988 and 1991; the Department of Preventive and Occupational Medicine of the Local Sanitary Unit of Reggio Emilia has followed the evolution of the local exhaust ventilation equipment supplied by the employer in that period. At the same time, the following measurements and observations were carried out: (a) cobalt exposure by personal sampling, (b) airborne cobalt measurements by area sampling, (c) biological monitoring of cobalt in urine, (d) health surveillance.  相似文献   
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