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The work is devoted to the issue of the rational use of the solar energy in the technological process of fruit drying based on the use of solar drying devices, which are applied in various sections of the agro-industrial centers of Ukraine. The aim of this research was intensification of the fruits drying process using the solar energy by combining an air collector and drying chamber into a single power unit. To achieve the aim the heat exchange diagnostic techniques with alternative potentials of diffusion and moisture transfer was developed. This technique differs from those existing for the heat exchange research in that it allows the intensity of the moisture evaporation from a unit of the material surface to be calculated, based on the synthesis of the moisture content and the irreversible major laws of processes of the heat exchange characteristics of the fruits drying using the solar dryer. The above model makes it possible to diagnose the heat exchange processes and analyze the mathematical model of the heat exchange processes. It also allows modeling the changeable diffusion and moisture transfer potentials based on the dependences obtained and for the purpose of a further application in the methods and devices development to control the strain-deformed state of the fruits during the drying process. The method is offered for the calculation of diffusion and moisture transfer during drying fruits in the solar dryer.

A significant part of thermal energy is lost precisely during its transportation. By increasing the efficiency of thermal insulation of pipelines, it is possible to reduce significantly heat loss around the world. The purpose of the paper is to develop and validate methods for increasing the efficiency of thermal insulation of pipelines by determining its optimal location. This purpose has been achieved by applying of a modified method for studying the process of heat loss, taking into account the radiation component, to calculate the heat loss and surface temperature of the thermal insulation with different spatial arrangements. For comparison, we analysed three options for the heat loss of pipe with a different spatial arrangement of thermal insulation coated with an aluminium reflective film facing outward, facing inward and in both directions. Comparison of these variants showed that it had been advisable to insulate the pipelines by installing an insulation layer coated with an aluminium reflective film facing in both directions. The main result of paper has been the proposed method for calculating of heat losses, which could be used in the design of thermal insulation of pipelines and the obtained data confirming the correspondence of theoretical calculations to actual values of the surface temperature of thermal insulation taking into account its various spatial arrangements. The importance of the results of the work lies in the possibility of using this technique to assess the effectiveness of thermal insulation of pipelines and determine the best solutions for its spatial location.

In modern manufacturing of livestock production, the outstanding value is allocated for a food supply. The main criterion for evaluating the quality of feed components is the nutrient content of the feed ration. However, in the process of the storage, the maintenance of the nutritious substances decreases for various reasons that are leading to decreasing livestock efficiency and increasing the cost. The results of the use of a two-phase compaction of the forage vegetable components on the example of the alfalfa are given in the article. The dependence coefficient of the nutritional preservation on density of the alfalfa put on storage are also presented in this article. The applied method and the results obtained can be used in the development and design offices to create new equipment based on the two-phase compaction of the fodder vegetable component mixes by preparing them for storage. The application of this method brings to decreasing losses of nutrients in the storage process which reduces the components cost in total with increasing additional weights and the milk productivity. [ABSTRACT FROM AUTHOR]

Energy independence of Ukraine is the key condition to further economic and social development of the state. Ukraine meets its requirements in oil by 85-90% due to import. But the oil price in the world market is constantly growing. It could not but affected the dramatic increase of the cost of agricultural products especially foods. Therefore, the necessity of searching the ways to replace oil feedstock for the production of fuels and lubricants by renewable raw materials is a strategic objective. The paper deals with the methodology for the determination of reliability indices for the elements of the functional systems of mobile machines which operate both on mineral (fossil) and organic fuels and oils. The laws of distribution of parametric failures have been determined. The laws have been used for the assessment of the average resorts. The average resorts values for the elements of functional systems were compared. This allowed to identify the parts with the lowest reliability. The reliability indices for the main elements of the systems of mobile machinery have been calculated as well as the reliability of the mobile machines in whole. The research has established when working on the organic fuels and lubricants all the reliability characteristics are lower than when running on the petroleum-based fuels and lubricants. The fact may be explained by the aggressive influence of biofuel methanol and light ends of organic oils on the constructional materials. [ABSTRACT FROM AUTHOR]

The non-equilibrium electronic transport through a nanoscale device composed of a single quantum dot between two metallic contacts is studied theoretically within the framework of the Keldysh formalism. The quantum dot consists of a single energy level subject to an applied magnetic field. Correlations due to the Coulomb repulsion between electrons on the dot are treated with a Green's function decoupling scheme which, although similar to the Hubbard-I approximation, captures some of the dynamics beyond. The scheme is exact in the so-called atomic limit, defined by vanishing tunneling between contacts and dot, and in the non-interacting limit, where the on-dot Coulomb repulsion is zero. Explicit analytic solutions, valid for arbitrary magnetic fields, are obtained for two important setups: (i) the stationary regime, with constant voltage bias between the leads, and (ii) the time-dependent regime for metallic leads with constant density of states of infinite width. In these regimes, the current through the dot is evaluated numerically for various parameter sets and its main features interpreted in terms of the underlying physical processes. The results are compared to the non-crossing approximation (NCA) and diagrammatic non-equilibrium quantum Monte-Carlo (QMC) where available.

Recent studies indicate that intrinsic promoter-mediated gene expression noise can confer a selective advantage under acute environmental stress by providing beneficial phenotypic diversity within cell populations. To investigate how extrinsic gene expression noise impacts the fitness of cell populations under stress, we engineered two nearly isogenic budding yeast strains; one carrying a two-step regulatory cascade that allows for precise control of the noise transmitted from a transcriptional regulator to a downstream stress-inducing gene, and one carrying a network with low constant upstream noise. The fitness and gene expression of these strains were compared under acute and prolonged stress exposure. Using a phenomenological modeling approach, we predicted that increased noise should confer a fitness advantage under high stress conditions, but reciprocally reduce the resistance of the population to low stress. The model also predicted that extrinsic noise might serve as a basis for phenotypic plasticity whereby gene expression distributions are modulated in response to prolonged stress. Experimentally, we confirmed the predicted differential fitness advantage of extrinsic noise under acute stress, as well as the predicted modulation of gene expression under prolonged stress. However, contrary to model predictions, strains with low and high extrinsic noise showed very similar adaptive responses to prolonged stress. This suggests that while phenotypic heterogeneity generated by noise in regulatory signals can confer increased robustness to acute stress, it is not a requirement for the observed long-term phenotypic plasticity.

The influence of the irradiation of different kinds on the induction of the structural mutations in the bacteria Escherichia coli is considered. The regularities of the Tn10 precise excision after accelerated 4He and 12C ions irradiations with different linear energy transfer (LET) were investigated. Dose dependences of the survival and relative frequency of the Tn10 precise excision were obtained. It was shown, that the relative frequency of the Tn10 precise excision is the exponential function from the irradiation dose. Relative biological efficiency (RBE), and relative genetic efficiency (RGE) were calculated, and were treated as the function of the LET.

The regularities of gamma-induced excision of transposon Tn10 in different rec-strains of E. coli cells after gamma-irradiation have been studied. The survival of cells and relative frequency of the Tn10 elimination as a function of the 137Cs gamma-radiation doses were investigated. RecN and recA-mutants of E. coli were used for study of the role of rec-genes in the gamma-induced transposon excision. It was shown that the induced excision in the recN mutant was reduced. The transposon excision in the recA mutant was not revealed. The obtained results let to conclude that recA, and recN genes are involved not only in DNA repair processes but also in the gamma-induced transposon excision in bacteria.

Antennae are known to be olfactory organs in Drosophila. The leg-aristae-wing complex (lawc) mutation causes a homeotic transformation of the arista (the fifth element of antenna) into tarsal elements. To test how the homeotic transformation of the arista into the tarsus can affect behavior, we studied the olfactory response in the lawc mutants. The data were carefully processed by statistical methods. In spite of a low penetrance of the trait of arista transformation, the mutant flies were found to be approximately half as perceptible to attractant odors than the wild-type flies.