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A B Tashirev

Publications and source records attributed to A B Tashirev.

8 recordsLinked to original sources
PubMedDate not supplied

[Accumulation of uranium, plutonium and americium by granulated microbial biosorbent].

A possibility of efficient extraction of 238U, 239Pu and 241Am by microorganisms from solutions with activity 520-3200 Bq/l has been shown on the example of microbial biosorbent (MBS). MBS presents water-resistant granules consisting of living microorganisms and nutrient substances. The ratio MBS:solution being equal to 1:100 and 1:20, microorganisms extracts 98.9 and 99.8% of 238U; 99.1 and 99.8% of 239Pu, 241Am, respectively. The worked out MBC granules may be utilized by burning with the 4-8 decrease of the volume. It is foreseen to use MBS in industrial processes of treatment of liquid radioactive waste (LRW) for uranium and transuranium elements.

Absorption↗
PubMedDate not supplied

[Extraction of a broad range of metals from sewage in the city of Kyiv by mixed microbe communities].

Accumulation of a wide range of metals by the "mixed microbe communities" (MMC) from Kyiv sewage treated in the air tank has been studied. MMC is a mixture of one or more synthrophical associations, such as microorganisms of fermented metantank deposit and cow manure. The exposure being 48 h and weight ratio of the phases MMC : sewage being 1:50, MMC lower the concentration of Ca, Fe, Zn, Cc, Au in sewage by 1 order; Cr, Mn, Co, Ag, Cd, Ba, Sm, Hf, Th--by 2 orders; Sc, Sb, La--by 3 orders. MMC may be used efficiently for deep tertiary treatment of sewage for toxical heavy metals, for extraction of rare-earth and non-ferrous metals from superdiluted solutions and industrial sewage.

Bacteria↗
PubMedDate not supplied

[Search for psychrophilic methylotrophic bacteria in biotopes of the Antarctica].

Psychrotolerant bacteria which use obligately methane were found in the moss samples and in soil-vegetation samples in the island part of the Antarctica during the VII expedition (2003) at the station "Akademik Vernadsky". The number of methane-oxidizing bacteria in the samples from the Antarctica (101- 10(3)/g of the sample) was lower than in the samples from the regions with moderate climate (10(2)- 106/g of the sample). Psychrotolerant strains of Methylobacteriium genus which use facultatively methanol were found in the bottom sediments of the fresh-water and Krasnoye lakes, as well as in the soil-plant samples. The psychrophilic strain which is probably a new species of the genus Methylobacterium has been isolated from one soil-plant sample from the Antarctica at 10 degrees C. It is established that most collection mesophilic strains of Methylobacterium, which have been isolated from the soil and plant phyllosphere in Ukraine, also could grow at 10 degrees C.

Adaptation, Biological↗
PubMedDate not supplied

[n-Chloroaniline transformation by Escherichia coli under anaerobic conditions].

In a medium without oxygen in the presence of nitrates, E. coli transforms p-chloranilin (p-CA) to yield a more hydrophilic compound which cannot be extracted with an organic solvent from water. The conditions for consecutive transformation of p-nitro-chlorobenzene (p-NCB) and p-CA have been determined: the reaction p-NCB leads to p-CA is inhibited by nitrates, p-CA transformation occurs in the presence of nitrates in the medium and depends on their concentration.

Anaerobiosis↗
PubMedDate not supplied

[Transformation of p-nitrochlorobenzene by Escherichia coli].

Microorganisms that have not been adapted to p-nitrochlorobenzene (p-NCB) are capable of transforming this compound. Washed cell of Escherichia coli, the resting culture and the homogenate of disintegrated cells transform p-NCB into p-chloroaniline (p-CA). The growing culture of E. coli (Eh = -210 mV) reduces the nitro group of p-NCB. If E. coli cells are separated from the cultural broth under strictly anaerobic conditions, the redox potential rises abruptly (Eh = -110 mV); the filtrate does not transform p-NCB into p-Ca. The rate at which E. coli reduces the nitro group of p-NCB depends on the redox potential of the medium. It is likely that any microorganism is capable of reducing p-NCB at a low value of the redox potential.

Biotransformation↗
PubMedDate not supplied

[Anaerobic glove box].

Anaerobic conditions can rapidly be created in a box designed for working with obligate anaerobic organisms by driving out the air with an inflatable ball. The box is fitted with a device for sterilising a microbiological loop.

Anaerobiosis↗
PubMedDate not supplied

[Radionuclide accumulation by a microbial sorbent].

Accumulation of a wide range of radionuclides by the microbial sorbent has been studied. The microbial sorbent represents granules stable in water solutions for a long period of time. The sorbent includes: concentrated biomass of metabolically active microorganisms, sources of carbon and energy, phosphorus, nitrogen, etc. Availability of nutrition sources in the sorbent provides for metabolic activity of microorganisms immobilized in granules. Metabolic activity of the sorbent was characterized. Physico-chemical sorption and metabolic activity of microorganisms lead to the extraction of a wide spectrum of radionuclides (51Cr, 54Mn, 60Co, 90Sr, 134Cs, 137Cs, 140La, 144Ce, 226Ra, 83Rb) from liquid radioactive waste. The extraction factor for some radionuclides was 10(5)-10(6). The waste sorbent may be utilized. Absence of water phase in the ash concentrate permits the radionuclides to be buried in borosilicate or volcanic glass (accepted time of existence 10(5)-10(7) years). The sorbent may be used to create new biotechnologies of radionuclide accumulation from water solutions.

Absorption↗