We observe a series of sharp resonant features in the tunnelling differential conductance of InAs quantum dots. We found that dissipative quantum tunnelling has a strong influence on the operation of nano-devices. Because of such tunnelling the current-voltage characteristics of tunnel contact created between atomic force microscope tip and a surface of InAs/GaAs quantum dots display many interesting peaks. We found that the number, position, and heights of these peaks are associated with the phonon modes involved. To describe the found effect we use a quasi-classical approximation. There the tunnelling current is related to a creation of a dilute instanton-anti-instanton gas. Our experimental data are well described with exactly solvable model where one charged particle is weakly interacting with two promoting phonon modes associated with external medium. We conclude that the characteristics of the tunnel nanoelectronic devices can thus be controlled by a proper choice of phonons existing in materials, which are involved.

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Thirty microbial phylotypes of microorganisms were found in the gastrointestinal tract of chicken belonging to the Hajseks White breed, and 38 phylotypes were found in the gastrointestinal tract of chicken belonging to the Hajseks Brown breed. The microbiome of the gastrointestinal tract of the chicken embryos of the Hajseks White breed was dominated by the typical representatives of avian intestinal microflora--bacteria of the family Enterobacteriaceae (47.3%), orders Actinomycetales (13.6%) and Bifidobacteriales (20.6%), and the family Lachnospiraceae (1.1%). The microbiome of the gastrointestinal tract of the chicken embryos of the Hajseks Brown breed was dominated by the pathogenic bacteria of the order Rickettsiales (94.8%). The metagenome of gastrointestinal tract of both breeds also contained a small number of genes of unidentified bacteria.

As we know, fi nished polyester fi bers are very diffi cult to dye, especially at low temperature (including room temperature). An exception is processes for dying undrawn fi bers. We have studied use of the crazing method to dye polyester fi bers at low temperatures with water-soluble dyes not having an affi nity for polyethylene terephthalate. We have studied the effect on sorption of cationic dyes from the composition, concentration, and temperature of the adsorption-active medium, and the dye concentration in the dye bath. The results of the study are the basis for developing a production process for obtaining colored special-purpose polyester fi bers.Polyester fi bers are very diffi cult to dye [1] due to their hydrophobicity, compact structure, and lack of a suffi cient number of functional groups in the polyethylene terephthalate (PET) macromolecules that can chemically react with active groups of the dyes. The most active centers of the PET macromolecules are the ester and terminal hydroxyl and carboxyl groups, due to which the polyester fi bers have an affi nity for disperse dyes but do not have an affi nity for direct dyes, acid dyes, or basic dyes. Surface dyeing of polyester fi bers is generally done in aqueous solutions with disperse dyes at elevated temperatures [2]. Polyester fi bers are not dyed at room temperature in practice. An exception is methods for dyeing the undrawn fi ber [3], making it possible to carry out the dyeing process directly in aqueous solutions of the dyes at low temperatures (below the glass transition temperature). The method involving crazing of polyester fi bers can be used for similar purposes.A characteristic feature of the crazing process is orientational drawing of the polyester fi lament in adsorption-active (AA) media [4]. Surface microdefects in the polymer and exposure to the medium lead to a change in the initial structure and mechanical properties of the fi laments. At the points where the liquid penetrates, stress concentrations appear and specifi c cracks are formed. In contrast to true fracture cracks, the appearance of microcracks in the polymers does not lead to their fracture. Such microcracks can sustain high loads. When the fi lament is deformed in the direction of the applied stress, orientation occurs at the locations of microcracks.When a freshly formed polyester fi lament is drawn in an adsorption-active medium in the presence of dye, the dye penetrates into the microcracks formed and when the pores are closed, it is anchored in the fi lament. For qualitative and quantitative evaluation of the dyeing process, we used the dye Cationic Red 2S, soluble in adsorption-active media. Under usual conditions, it does not dye polyester fi bers and is not chemically bound; but when it penetrates into microcracks, when the pores are closed it is mechanically held in the fi ber, ensuring saturated and permanent dyeing.Crazing of polymers in liquid media is a complicated multistep process which depends on many factors. We have studied the effect of the following pa...