Search Results: 1 - 10 of 100 matches for " "
All listed articles are free for downloading (OA Articles)
Page 1 /100
Display every page Item
Toxicity Evaluation of Cyanogen Wastes and Antimony Smelting Alkali Wastes by Daphnia Magnet Straus

Gao Shirong,Xiu Ruiqin,

环境科学 , 1991,
Abstract: The toxicity test on solid wastes of cyanogen and antimony smelting alkali wastes with Daphnia magaa as test organism is introduced in this paper. The results show that the solid wastes of cyanogen and antimony smelting alkali wastes were toxic to the test organism. For cyanogen wastes, the EC50 values (median effective concentration) at exposure time of 24 hr, 48 hr and 96 hr were determined to be 7.5%, 0.24% and 0.167%, respectively. While for antimony smelting alkali wastes, the EC50 value at exposure time of 96 hr was found to be 89%. The LC50 for cyanogen wastes at 48 hr and 96 hr were calculated to be 0.43% and 0.19%, respectively. The results, show that the cyanogen wastes and antimony smelting alkali wastes were highly toxic to aquatic organisms. It should be indicated that Daphnia magna bioassay is a rapid and sensitive method in environmental toxicological studies.
Evaluation of potential dietary toxicity of heavy metals in some common Nigerian beverages: A look at antimony, tin and mercury
I.I. Roberts,O.E. Orisakwe
QScience Connect , 2011, DOI: 10.5339/connect.2011.2
Abstract: There is currently little information on the composition of heavy metals in beverages imported and locally produced in Nigeria. The study quantitatively determined the composition of antimony (Sb), tin (Sn) and mercury (Hg) in 50 different beverage samples and evaluated the extent of violation of guideline values. Analysis of the beverage samples for the presence of Sb, Sn, and Hg was carried out using an atomic absorption spectrophotometer (AAS) 929. The mean values detected for mercury, tin and antimony (±SE) in fruit juices and soft drinks were 2.39±0.25, 3.66±0.22 and 0.49±0.048 μg/l; 2.93±0.34, 3.60±0.46 and 0.49±0.10 μg/l in dairy drinks and 0.94±0.02, 4.34±0.48 and 0.48±0.05 μg/l in bottled water samples respectively. While antimony detected in all products was below guideline values, mercury and tin were above the acceptable levels established by the World Health Organization, United States Environmental Protection Agency and European Union in most samples tested.
The exposure to and health effects of antimony  [cached]
Cooper Ross,Harrison Adrian
Indian Journal of Occupational and Environmental Medicine , 2009,
Abstract: Context: This minireview describes the health effects of antimony exposure in the workplace and the environment. Aim: To collate information on the consequences of occupational and environmental exposure to antimony on physiological function and well-being. Methods: The criteria used in the current minireview for selecting articles were adopted from proposed criteria in The International Classification of Functioning, Disability and Health. Articles were classified from an acute and chronic exposure and toxicity thrust. Results: The proportion of utilised and non-utilised articles was tabulated. Antimony toxicity is dependent on the exposure dose, duration, route (breathing, eating, drinking, or skin contact), other chemical exposures, age, sex, nutritional status, family traits, life style, and state of health. Chronic exposure to antimony in the air at levels of 9 mg/m 3 may exacerbate irritation of the eyes, skin, and lungs. Long-term inhalation of antimony can potentiate pneumoconiosis, altered electrocardiograms, stomach pain, diarrhea, vomiting, and stomach ulcers, results which were confirmed in laboratory animals. Although there were investigations of the effect of antimony in sudden infant death syndrome, current findings suggest no link. Antimony trioxide exposure is predominant in smelters. Mining and exposure via glass working, soldering, and brazing are also important. Conclusion: Antimony has some useful but undoubtedly harmful effects on health and well-being and measures need to be taken to prevent hazardous exposure of the like. Its biological monitoring in the workplace is essential.
Reduced Graphene Oxide Supported Antimony Species for High-Performance Supercapacitor Electrodes  [PDF]
Mateusz Ciszewski,Andrzej Mianowski,Ginter Nawrat,Piotr Szatkowski
ISRN Electrochemistry , 2014, DOI: 10.1155/2014/826832
Abstract: Antimony species was chemically anchored on graphene oxide using antimony (III) chloride precursor and then converted to the reduced graphene oxide-antimony species composite by a well-established polyol method. The resultant composite was successfully used as supercapacitor electrodes in a two-electrode symmetric system with aqueous electrolyte. The specific capacitance calculated from the galvanostatic charge/discharge curves obtained for this composite was 289?F/g. The enhanced capacitance results were confirmed by the electrochemical impedance spectroscopy and cyclic voltammetry. The high capacitance of the reduced graphene oxide-antimony species composite arises from the combination of double-layer charging and pseudocapacitance caused by the Faradaic reactions of the intercalated antimony species and residual surface-bonded functional groups. 1. Introduction Antimony is widely used in semiconductors, antifriction alloys, small arms and tracer bullets, and cable sheathing and in large quantities as a flame retarding additive [1]. It has been widely used in the past to enhance the hardness and the mechanical stability of lead alloys in batteries [2]. However, its usage was gradually limited because of toxicity, mostly of the trivalent species. In the lead batteries, antimony is generally known to be able to pass on a negative electrode through corrosion of current leads and decrease in the battery service life [3]. The detailed description of antimony reactions in lead batteries was given by Pavlov et al. [4], who suggested that the influence of the antimony on the lead battery work depends on antimony species used in battery preparation. In case of the lead electrodes immersed in the antimony solution, formation of ions is observed that passivates the lead and decreases the capacitance. While for Pb-Sb alloys in sulfuric acid solution formation of antimony complexes of the type is observed that have a beneficial effect on the capacitance of electrodes. It is well known that antimony corrodes easily but results [5] suggest that the antimony-containing corrosion layer discharges with difficulty, and thus the active material discharges more readily than the corrosion layer and a passivation layer does not form at the grid/active material interface. So it appears that addition of antimony to the active material of electrode effectively retards capacitance loss. These opinions seem to be true because antimony has been thoroughly examined as an additive in newer energy sources, that is, lithium-ion batteries, liquid metal batteries, and fuel cells. In
Arsenic and Antimony Transporters in Eukaryotes  [PDF]
Ewa Maciaszczyk-Dziubinska,Donata Wawrzycka,Robert Wysocki
International Journal of Molecular Sciences , 2012, DOI: 10.3390/ijms13033527
Abstract: Arsenic and antimony are toxic metalloids, naturally present in the environment and all organisms have developed pathways for their detoxification. The most effective metalloid tolerance systems in eukaryotes include downregulation of metalloid uptake, efflux out of the cell, and complexation with phytochelatin or glutathione followed by sequestration into the vacuole. Understanding of arsenic and antimony transport system is of high importance due to the increasing usage of arsenic-based drugs in the treatment of certain types of cancer and diseases caused by protozoan parasites as well as for the development of bio- and phytoremediation strategies for metalloid polluted areas. However, in contrast to prokaryotes, the knowledge about specific transporters of arsenic and antimony and the mechanisms of metalloid transport in eukaryotes has been very limited for a long time. Here, we review the recent advances in understanding of arsenic and antimony transport pathways in eukaryotes, including a dual role of aquaglyceroporins in uptake and efflux of metalloids, elucidation of arsenic transport mechanism by the yeast Acr3 transporter and its role in arsenic hyperaccumulation in ferns, identification of vacuolar transporters of arsenic-phytochelatin complexes in plants and forms of arsenic substrates recognized by mammalian ABC transporters.
Preparation and properties of antimony thin film anode materials
Shufa Su,Gaoshao Cao,Xinbing Zhao
Chinese Science Bulletin , 2004, DOI: 10.1007/BF03183417
Abstract: Metallic antimony thin films were deposited by magnetron sputtering and electrodeposition. Electrochemical properties of the thin film as anode materials for lithium-ion batteries were investigated and compared with those of antimony powder. It was found that both magnetron sputtering and electrodeposition are easily controllable processes to deposit antimony films with flat charge/discharge potential plateaus. The electrochemical performances of antimony thin films, especially those prepared with magnetron sputtering, are better than those of antimony powder. The reversible capacities of the magnetron sputtered antimony thin film are above 400 mA h g 1 in the first 15 cycles.

Bao Chao Huang Ji-shang,

金属学报 , 1978,
Abstract: Antimony white as a pigment is mainly judged by the degree of whiteness. With a view to improving the quality of the product, tests were carried out to investigate the effect of impurities contamination, the shape and size of the grains, and the crystal structure of antimony oxides. At the same time, methods of producing superfine antimony white on a large scale were also investigated. It was found that amongst the many factors the crystal structure of the grains was most important, thus the greater the amount of cubic antimony trioxide present, the better the quality of antimony white as revealed by its whiteness. Furthermore, long-time tests on a large scale showed that the best quality of antimony white powders could be obtained by suitable control of the primary and secondary oxidizing blast, the forced-air cooling flow, and the reaction chamber temperature.
Compounds with gold-antimony bonds
Maurice C. Muller
Gold Bulletin , 1974, DOI: 10.1007/BF03215035
Abstract: A new field of interest in the chemistry of gold has been opened up by the preparation and characterisation of complexes containing gold-to-antimony metal-metal bonds. These exhibit catalytic properties similar to those of the well known platinum-tin complexes, and may also have potential value in the homogeneous hydrogenation of olefins.
An alternative antimonial schedule to be used in cutaneous leishmaniasis when high doses of antimony are undesirable
Oliveira-Neto, Manoel Paes de;Mattos, Marise da Silva;
Revista da Sociedade Brasileira de Medicina Tropical , 2006, DOI: 10.1590/S0037-86822006000400001
Abstract: despite more than half a century of use in leishmaniasis, antimony therapy still presents serious problems concerning dosage and toxicity. low and high doses have been shown to be equally effective. in this paper, the feasibility of injecting one ampoule of meglumine antimoniate intramuscularly every other day until clinical cure is demonstrated, while studying a series of 40 cutaneous leishmaniasis cases. total dose used varied from 1,822.5 to 12,150mg of pentavalent antimony and total time of treatment varied from 3 to 10 weeks, with 86% efficacy. thirty-six out of the 40 patients are still on follow-up with a mean time of 10.7 ± 7 months and a median of 9 months. no relapse or mucosal lesions have been noted so far. the schedule showed good tolerance and easy application and its efficacy was comparable to the officially recommended who schedule. therefore, such a schedule represents a valuable alternative for the cases with high toxicicity to antimony or daily injections are an obstacle to the treatment.
The influence of pet containers on antimony concentration in bottled drinking water
Peri?-Gruji? Aleksandra A.,Radmanovac Aleksandar R.,Stojanov Aleksander M.,Pocajt Viktor V.
Hemijska Industrija , 2010, DOI: 10.2298/hemind100419037p
Abstract: Antimony trioxide (Sb2O3) is the most frequently used catalyst in the polyethylene terephthalate (PET) manufacture. As a result, antimony is incorporated into PET bottles at concentration level of 100-300 mg/kg. PET containers are used for drinking water and beverages, as well as food packaging and in the pharmaceutical industry. Thus, it is important to understand the factors that may influence the release of antimony from the catalysts into water and other products, since antimony is potentially toxic trace element. In this paper, the antimony content in nine brands of bottled mineral and spring water from Serbia, and seven brands of bottled mineral and spring water from EU countries was analyzed. The measurements were conducted using the inductively coupled plasma-mass spectrometry (ICP-MS) technique. In the all examined samples the antimony concentration was bellow the maximum contaminant level of 5 μg/L prescribed by the Serbian and EU regulations. Comparison of the content of antimony in PET bottled waters with the content of antimony in water bottled commercially in glass and the natural content of antimony in pristine groundwaters, provides explicit evidence of antimony leaching from PET containers. Since waters bottled in PET have much greater concentration ratio of Sb to Pb than corresponding pristine groundwaters, it can be assumed that bottled waters cannot be used as the relavant source for the study of the natural antimony content in groundwaters. There is a clear relation between the quality of water in bottles (composition, ion strength) and antimony leaching rate. Moreover, while the rate of antimony leaching is slow at temperatures below 60 oC, at the temperature range of 60-80 oC antimony release occurs and reaches maximum contaminant level rapidly. As antimony can cause both acute and chronic health problems, factors that promote the increase of antimony concentration should be avoided.
Page 1 /100
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.