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Konstantinov A Bejan D Bunce NJ Chittim B McCrindle R Potter D Tashiro C 《Chemosphere》2008,72(8):1159-1162
Electrochemical debromination of the commercial decabromodiphenyl ether flame retardant DE-83 in partly aqueous tetrahydrofuran (THF) solution gave lower brominated congeners by sequential loss of bromine atoms. Hydrodebromination was most facile for the most heavily brominated congeners. It involves initial electron transfer and proton transfer from water, rather than hydrogen atom abstraction from THF, as shown by experiments with deuterated water. The product distribution from electrolysis involves preferential loss of bromine meta- and para- to the ether linkage, comparable with the products of metabolism of BDE-209 in various organisms. Significantly, the environmentally relevant congeners BDE-47, BDE-99, and BDE-154 were not major products of debromination of BDE-209 by the electron transfer mechanism. 相似文献
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Polybrominated diphenyl ethers (PBDEs) are ubiquitous environmental contaminants due to their use as additive flame-retardants. Conventional catalytic hydrogenolysis in methanol solution and electrocatalytic hydrogenolysis in aqueous methanol were examined as methods for debrominating mono- and di-bromodiphenyl ethers, as well as a commercial penta-PBDE mixture, in each case using palladium on alumina as the catalyst. Electrocatalytic hydrogenolysis employed a divided flow-through batch cell, with reticulated vitreous carbon cathodes and IrO2/Ti dimensionally stable anodes. Both methods gave efficient sequential debromination, with essentially complete removal of bromine from the PBDEs, but the electrocatalytic method was limited by the poor solubility of PBDEs in aqueous methanol. 相似文献
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Konstantinova Elizaveta Burachevskaya Marina Mandzhieva Saglara Bauer Tatiana Minkina Tatiana Chaplygin Victor Zamulina Inna Konstantinov Alexandr Sushkova Svetlana 《Environmental geochemistry and health》2022,44(2):349-368
Environmental Geochemistry and Health - Lake Atamanskoye is one of the most polluted aquatic environments in the South of Russia. This water body was affected by long-term pollution by effluent... 相似文献
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Commercial octabromodiphenyl ether mixtures, containing hexabromodiphenyl ethers and heptabromodiphenyl ethers were listed in Annex A of the Stockholm Convention on May 2009 (Fourth Conference of the Parties) (UNEP, 2009a). Four compounds are specifically mentioned: 2,2′,4,4′,5,5′-hexabromodiphenyl ether (BDE-153), 2,2′,4,4′,5,6′-hexabromodiphenyl ether (BDE-154), 2,2′,3,3′,4,5′,6-heptabromodiphenyl ether (BDE-175), and 2,2′,3,4,4′,5′,6-heptabromodiphenyl ether (BDE-183). Presumably they were identified as key components of commercial mixtures and found to be present in environmental samples. However, since BDE-175 and BDE-183 co-elute on common HRGC columns, the presence of BDE-175 as an important component in technical octa-BDE mixtures has not been illustrated. The successful HRGC/LRMS separation of a 1:1 mixture of BDE-175 and BDE-183, as well as 1H NMR analysis of technical material, has allowed us to confirm that this congener is not present in technical products (e.g. Great Lakes DE-79™) in quantifiable amounts. 相似文献
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Konstantinov A Arsenault G Chittim B Kolic T MacPherson K McAlees A McCrindle R Potter D Reiner EJ Tashiro C Yeo B 《Chemosphere》2006,64(2):245-249
Very little data is available about the presence of the brominated flame retardant, DBDPE, in the environment. This study reports the characterization of [(13)C(14)]-decabromodiphenylethane and the use of this surrogate standard to positively identify and quantify the presence of DBDPE in sewage sludge samples. The large difference in response factors between BDE-209 and DBDPE predicates the use of [(13)C(14)]-decabromodiphenylethane as a surrogate standard to improve the accuracy when determining the levels of DBDPE in environmental samples. 相似文献
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Konstantinova Elizaveta Minkina Tatiana Konstantinov Alexandr Sushkova Svetlana Antonenko Elena Kurasova Alina Loiko Sergey 《Environmental geochemistry and health》2022,44(2):409-432
Environmental Geochemistry and Health - This study investigated levels and sources of pollution and potential health risks associated with potentially toxic elements (PTEs) and polycyclic aromatic... 相似文献
7.
Arsenault G Konstantinov A Marvin CH MacInnis G McAlees A McCrindle R Riddell N Tomy GT Yeo B 《Chemosphere》2007,68(5):887-892
Hexabromocyclododecane (HBCD) is prepared commercially by bromination of cis,trans,trans-cyclododecatriene (ctt-CDT) and widely used as a flame retardant, particularly in polystyrene foams. Commercial HBCD consists largely of three diastereomers, alpha-, beta-, and gamma-HBCD, the structures of which have been known for many years. Recently, the presence in the mixture of small amounts of two minor diastereomers, delta- and epsilon-HBCD, has been reported. Bearing in mind the manner in which commercial HBCD is generated, it was anticipated that these components are probably formed by bromination of trans,trans,trans-cyclododecatriene (ttt-CDT), a common contaminant in commercial ctt-CDT. Indeed, when a sample of ttt-CDT was brominated it gave two products, the NMR spectra and LC/MS and GC/MS behaviour of which confirmed that they are identical to the minor components, delta- and epsilon-HBCD, present in commercial HBCD. 相似文献
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Experience in organizing a natural reference area (standard) for studies on the functional dynamics of ecosystems in connection
with paludification and forest-bog relationships is described. The essence of studies on ecosystem dynamics with the aid of
natural standards and key plots is described using an example of the Yenisei region of Western Siberia. Arguments are presented
for the necessity of using a differential approach to studies on the dynamics of nature and taking into account local ecological
conditions while extrapolating the results of these studies to other geographic regions. 相似文献
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G. V. Matyashenko V. N. Shmakov Yu. M. Konstantinov G. A. Belogolova 《Russian Journal of Ecology》2005,36(6):396-399
The accumulation of fluorine in the trunk wood and branches of Larix gmelinii growing on soils with a naturally increased fluoride content and of L. sibirica growing in a zone affected by atmospheric emissions from an aluminum plant has been studied. Based on results of in vivo and in vitro experiments, it is concluded that larch trees manifest individual differences in their response to fluorine. 相似文献
10.
Some results of the ecocenotic analysis of forest and bog mosses, widespread or locally occurring in the taiga zone of West Siberia, are described. The species were compared with respect to their edaphic requirements, and a relationship was observed between geographic variation in cenotic parameters and changes in macroconditions of the physical environment, primarily in lithologic, geomorphological, and climatic conditions. The results of analysis confirmed the existence of such a relationship, but moss species proved to differ in their response to changes in physiographic conditions. 相似文献
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