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T Antonova

Publications and source records attributed to T Antonova.

17 recordsLinked to original sources
PubMed2006

Measurement of the interaction force among particles in three-dimensional plasma clusters.

The interaction forces between particles have been studied in a 3D plasma cluster under weak external confinement. A suitable combination of dc and rf applied to a small electrode provided gravity compensation, uniform over dimensions much larger than the cluster itself. The forces acting on the particles could be reconstructed due to unique three-dimensional diagnostics, which allow us to obtain coordinates and velocities of all the particles simultaneously. The measurements yield a maximum (external) confinement force of 1.4 x 10(-15)N and interparticle force that is repulsive at short distances and attractive at larger distances, with a maximum attractive force of 2.4 X 10(-14)N at particle separation 195 microm.

Journal Article↗
PubMed2004

Diagnostics of the electronegative plasma sheath at low pressures using microparticles.

Levitated particles are a new powerful diagnostic of the midplasma sheath region. They can reveal features undetectable either to plasma or to surface measurements. The equilibrium position of microparticles suspended in an oxygen plasma sheath, together with a model of the levitation force and Langmuir probe measurements, gives evidence of secondary electropositive plasmas in the already established plasma sheath, in the range of parameters where the modified Bohm criterion breaks down into multiple solutions.

Journal Article↗
PubMed1990

[Genetic studies of a Bacillus subtilis producer of a milk-coagulating enzyme complex].

Dissociation is a phenomenon when from an initial bacterial population different forms in morphological, physiological aspects have been produced. For bacterial producers of biologically active substances the investigation of this process is important for industrial microbiology. Bacillus subtilis 76 is a producer of proteolytic enzyme complex with milk-coagulating effect. It dissociates in several different forms. Some of them (M, R, S) have been studied. They are plasmidless, prototrophs and tiostrepton-resistant. The results obtained are of a great importance for the future genetic experiments.

Animals↗
PubMedDate not supplied

[The isolation and characteristics of a chemically modified allergen (allergoid) from Dermatophagoides pteronyssinus mites].

Chemically modified allergens (allergoids) were obtained from house dust mites (Dermatophagoides pteronyssinus). The allergenicity of allergoids in comparison with commercial mite allergen was determined by the skin prick test and by the in vitro test of degranulation of passively sensitized rat mast cells. Changes in allergoid molecules were determined with the use of gel filtration in a column packed with Sephadex G-75, isoelectric focusing in polyacrylamide gel, the determination of the concentration of end amino groups and the enzymatic activity of preparations, as well as HPLC. The possibility of using these methods for controlling the process of modification was studied. The results confirmed the fact that the modification on the allergenic preparation really occurred and the allergenic activity of allergoids was low.

Allergens↗