21 research outputs found
Technological qualities of natural bitumens of Tatarstan depending on chemical and geochemical characteristics of their composition
A variety of composition of natural bitumens of the Permian sediments of Tatarstan territory is given. The necessity of differentiation of the given raw by chemical and geochemical parameters of their composition is proved. Perspective lines of use of various types of natural bitumens are considered
Genesis of biomarker hydrocarbons in the environment and their role in assessing an oil pollution source
Oil spills are classified according to chemical types that reflect qualitative and quantitative changes in petroleum composition during biodegradation in soil. Possible trends in composition of biomarker petroleum hydrocarbons in polluted soil, as determined by natural and climatic conditions and by activation of soil microflora, were revealed. It was shown that the use of selective bioremediation methods could lead to a noticeable redistribution of the relative amount of C27 : C28 : C29 steranes in marine crude oils owing to more intense degradation of C 27 steranes (5α, 14β, 17β, 20R and 20S, as well as 5α, 14α, 17α, 20R and 20S) as compared with their higher C29 homologues. The observed changes in the composition of steranes suggest another, namely, terrigenous origin of petroleum, and, thus, may lead to an erroneous conclusion concerning the genotype of crude oil as a pollution source. It was found that hopane hydrocarbons are highly stable under similar conditions. It was shown that the set of biomarker hydrocarbons might be useful as biological indicators in the assessment of a petroleum pollution source. © MAIK "Nauka/Interperiodica"
Identification of substitutional nitrogen and surface paramagnetic centers in nanodiamond of dynamic synthesis by electron paramagnetic resonance
Production of nanodiamond particles containing substitutional nitrogen is important for a wide variety of advanced applications. In the current work nanodiamond particles synthesized from a mixture of graphite and hexogen were analyzed to determine the presence of substitutional nitrogen using pulsed electron paramagnetic resonance (EPR) spectroscopy. Nitrogen paramagnetic centers in the amount of 1.2 ppm have been identified. The spin relaxation characteristics for both nitrogen and surface defects are also reported. A new approach for efficient depletion of the strong non-nitrogen EPR signal in nanodiamond material by immersing nanodiamond particles into ice matrix is suggested. This approach allows an essential decrease of the spin relaxation time of the dominant non-nitrogen defects, while preserving the substitutional nitrogen spin relaxation time.Copyright © 2011 American Scientific Publishers. All rights reserved
Mutations in the gene of human type IIb sodium-phosphate cotransporter SLC34A2
Type IIb sodium-phosphate cotransporter (NaPi2b) provides phosphate intake in the cells of some epithelial tissues, osteoblasts and odontoblasts. Abnormal expression of NaPi2b has been detected in some types of epithelial tumors. An alteration in NaPi2b activity, caused by mutations in transporter gene SLC34A2, has been recently revealed in patients with pulmonary alveolar microlithiasis, an autosomal recessively inherited disease, characterized by deposition of calcium-phosphate precipitates in the lungs. In the present study we have combined the information about all mutations found to date in the coding sequence of SLC34A2 and its transcript, compiled their map, and analysed their relevance to the function of NaPi2b
Creation of cellular models for the analysis of sodium-dependent phosphate transporter NaPi2b, a potential marker for ovarian cancer
The aim of present study was to develop a model for a functional analysis of a recently identified marker of the ovarian cancer – sodium-dependent phosphate transporter NaPi2b. For this purpose, we have created HEK293 stable cell lines expressing wild type or mutant forms of NaPi2b (T330V substitution in a large extracellular loop and a 6 amino acid residues deletion in the C-terminal cytoplasmic tail), revealed in the ovarian cancer cell lines. The expression of wild type and mutant forms NaPi2b in the stable cell lines created was confirmed by Western-blot analysis with monoclonal antibodies against NaPi2b. The cellular models described here will be useful for studying the function of sodium-dependent phosphate transporter NaPi2b in health and disease
Technological qualities of natural bitumens of Tatarstan depending on chemical and geochemical characteristics of their composition
A variety of composition of natural bitumens of the Permian sediments of Tatarstan territory is given. The necessity of differentiation of the given raw by chemical and geochemical parameters of their composition is proved. Perspective lines of use of various types of natural bitumens are considered
Technological qualities of natural bitumens of Tatarstan depending on chemical and geochemical characteristics of their composition
A variety of composition of natural bitumens of the Permian sediments of Tatarstan territory is given. The necessity of differentiation of the given raw by chemical and geochemical parameters of their composition is proved. Perspective lines of use of various types of natural bitumens are considered
Technological qualities of natural bitumens of Tatarstan depending on chemical and geochemical characteristics of their composition
A variety of composition of natural bitumens of the Permian sediments of Tatarstan territory is given. The necessity of differentiation of the given raw by chemical and geochemical parameters of their composition is proved. Perspective lines of use of various types of natural bitumens are considered
Genesis of biomarker hydrocarbons in the environment and their role in assessing an oil pollution source
Oil spills are classified according to chemical types that reflect qualitative and quantitative changes in petroleum composition during biodegradation in soil. Possible trends in composition of biomarker petroleum hydrocarbons in polluted soil, as determined by natural and climatic conditions and by activation of soil microflora, were revealed. It was shown that the use of selective bioremediation methods could lead to a noticeable redistribution of the relative amount of C27 : C28 : C29 steranes in marine crude oils owing to more intense degradation of C 27 steranes (5α, 14β, 17β, 20R and 20S, as well as 5α, 14α, 17α, 20R and 20S) as compared with their higher C29 homologues. The observed changes in the composition of steranes suggest another, namely, terrigenous origin of petroleum, and, thus, may lead to an erroneous conclusion concerning the genotype of crude oil as a pollution source. It was found that hopane hydrocarbons are highly stable under similar conditions. It was shown that the set of biomarker hydrocarbons might be useful as biological indicators in the assessment of a petroleum pollution source. © MAIK "Nauka/Interperiodica"
Genesis of biomarker hydrocarbons in the environment and their role in assessing an oil pollution source
Oil spills are classified according to chemical types that reflect qualitative and quantitative changes in petroleum composition during biodegradation in soil. Possible trends in composition of biomarker petroleum hydrocarbons in polluted soil, as determined by natural and climatic conditions and by activation of soil microflora, were revealed. It was shown that the use of selective bioremediation methods could lead to a noticeable redistribution of the relative amount of C27 : C28 : C29 steranes in marine crude oils owing to more intense degradation of C 27 steranes (5α, 14β, 17β, 20R and 20S, as well as 5α, 14α, 17α, 20R and 20S) as compared with their higher C29 homologues. The observed changes in the composition of steranes suggest another, namely, terrigenous origin of petroleum, and, thus, may lead to an erroneous conclusion concerning the genotype of crude oil as a pollution source. It was found that hopane hydrocarbons are highly stable under similar conditions. It was shown that the set of biomarker hydrocarbons might be useful as biological indicators in the assessment of a petroleum pollution source. © MAIK "Nauka/Interperiodica"