№ 132(8), October, 2017
Public date: 31.10.2017
Archive of journal: Articles count 111, 292 kb
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01.00.00 Physical-mathematical sciences
PROBABILISTIC MODEL OF THE PROCESS OF REDUCTION OF THE PRICE FOR PLANNED ACTIONS
01.00.00 Physical-mathematical sciences
Description
The soil fertility increase issues are very relevant now. Intensive development of agriculture cannot be made effectively without complex actions for farmlands protection from different types of degradations. On the one hand, it is necessary to ensure the maximum harvest of crops, and to preserve and increase the fertility of the soil and prevent negative anthropogenic impact on the environment on the other. For an extended reproduction of soil fertility, a system of measures is necessary for introduction of mineral and organic fertilizers into the soil, agrotechnical and reclamation methods, stimulation of humus formation processes, and so on. Therefore, methods are important that allow us to estimate the planned measures in advance to improve soil fertility and to eliminate environmental damage. In the article, the estimated parameters are treated by random variables. This allows us to consider the uncertainty in terms of probability distributions. It is offered a probabilistic model of the process of reducing the price of the proposed activity. Mathematical expectation, variance, distribution density of the considered random variable probabilities as the main characteristics of the object state price are calculated. The model can be used to address issues of rational use of land, scientifically based land management organization, when drafting land reclamation project
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01.00.00 Physical-mathematical sciences
Description
The concept of generic polynomial appeared in Saltman’s works at the end of the last century and it is connected with the inverse problem of Galois theory, which is still far from its complete solution. Let G be a finite group and K be a field, the polynomial f(x,t1, … , tn) with coefficients from the field K is generic for the group G, if Galois group of this polynomial over the field K(t1, … , tn) is isomorphic G and if for any Galois extension L/K with Galois group isomorphic G there are such values of parameters ti = ai , i = 1,2, … , n, that the field L is the splitting field of the polynomial f(x,a1, … , an) over K. Generic polynomials over a given field K and a given finite group G do not always exist, and if they exist then it’s not easy to construct them. For example, for a cyclic group of the eight order C8 there is no generic polynomial over the field of rational numbers Q, although there are found specific polynomials with rational coefficients having Galois group isomorphic C8. Therefore, this is of interest to construct generic polynomials for the group G in cases when G is a direct product of groups of lower orders. In this study we show to solve this problem in case when G is a direct product of certain cyclic groups and there is a type of corresponding generic polynomials. Moreover, we give constructions over the fields of characteristic 0 and over the fields of characteristic 2
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SIMULATION OF A PLASMA CHANNEL AND TRACK IN MOTION OF PLASMA SOURCE IN CONDUCTIVE ENVIRONMENT
01.00.00 Physical-mathematical sciences
Description
A model is developed that describes the formation of the plasma channel and the trace when moving in a conducting medium of various objects that are sources of plasma - ball lightning, plasmoids, charged particles, and so on. To describe the contribution of conduction currents, we modified the standard electrostatic equation considering the vortex component of the electric field. As a result of this generalization, a system of parabolictype nonlinear equations is formulated that describes the formation of the plasma channel and the track behind the moving object. In this formulation, the problem of the formation of the lightning channel in weak electric fields, characteristic for atmospheric discharges of cloudearth, is solved. Numerical simulation of the motion of plasma sources in a region with a ratio of the sizes 1/100, 1/200 makes it possible to find the shape of the channel and the total length of the track, as well as the branching regimes. It was previously established that there are three streamer branching mechanisms. The first mechanism is associated with the instability of the front, which leads to the separation of the head of the streamer into two parts. The second mechanism is related to the instability of the streamer in the base region, which leads to the branching of the streamer with the formation of a large number of lateral streamers closing the main channel of the streamer to the cathode. The third branching mechanism, observed in experiments, is associated with the closure of the space charge to the anode through the streamer system. These branching mechanisms are also revealed when the leader is spread. Numerical experiments have revealed a new channel branching mechanism and a trace behind a moving plasma object, caused by the conductivity of the medium
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QuЕChERS SAMPLE PREPARATION IN THE DETERMINATION OF PESTICIDES OF DIFFERENT CHEMICAL CLASSES BY HPLC
Description
The method has been developed of simultaneous determination of active ingredients of different kinds of pesticides in biological tissues (fish liver) by applying HPLC with ultra-violet detection and the rapid method of QuEChERS sample preparation. We defined optimum volume and composition of the reagents for the extraction, time of centrifugation and ultrasound treatment, the origin and composition of sorbents that ensure maximum extraction of the substances studied and further cleanup of interfering substances. Acetonitrile was used as a solvent. The extraction was carried out in the presence of a buffering mixture - trisodium citrate dihydrate and disodium citrate hemihydrate. Bondesil PSA bulk sorbents (alkylated amine containing two amine functional groups - secondary and primary) and C18E (reversed-phase sorbent based on silica gel with grafted octadecylsilane groups were used to purify the extract from coextractable substances (fats, proteins, sugars, organic and fatty acids, pigments and other impurities). The degree of extraction of the analyzed active ingredients of pesticides from the liver of fish was 79%. The detectable pesticide concentrations ranged from 0,4 to 0,97 mg/kg. The relative standard deviation of the analysis results amounted to 0,01-0,14
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ALTERNATIVE MODEL OF CALCULATIONS OF VALUES OF ATOMIC RADIUS
Description
The article presents the results of the development of an alternative model for calculating the values of atomic radius. A formula was derived for calculating the atomic radius of the elements of the Periodic System of DI Mendeleev. The optimal calculation conditions for the proposed model are found. It is shown that the curve of the dependence of the value of the correction coefficient x on the atomic number of the element in form coincides with the dependence of the ionization energy on the charge number
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Description
The results of investigation of melanoidin’s formation early stages in acidic ethanolic D-glucose – p-toluidine model system are presented. Based on the elemental analysis, IR- and UV-spectroscopy data obtained we have shown, that in system studied Amadori rearrangement product undergo the aryl amine elimination during browning to form a nonnitrogenous reductons with antioxidative activity in processes of linoleic acid oxidation. It is also noted, that in system studied inhibition of carbohydrate’s destruction occurs because of non-reactive O-ethylglycosides formation. The data obtained may be useful for technology of carbohydrate-containing raw material
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STABILIZATION OF MRNA CEREALS IN VITRO UNDER THE SILICON INFLUENCE
Description
The differential stability of mRNA is an important mechanism for posttranscriptional regulation of gene expression in eukaryotes. Messenger RNA stability is controlled by specific genes and growth conditions. The review examines the theoretical possibility of mRNA stabilization in vivo as a consequence of replacing carbon atoms (C) or phosphorus (P), composed of nucleic acid on the silicon (Si) atom. During isolation of poly-(A)+mRNA from plant tissues by the two-cycle affinity chromatography on poly-(U)-Sepharose, regular changes in poly- (A)++mRNA yield were observed. The changes varied both with the plant genotype and growth conditions. Celite treatment of heated and unheated total RNA preparations from developing corn kernels and from green and etiolated wheat seedlings. Messenger RNA that differed in the length of poly- (A)-sequences was used for hybridization. It is evident that a reduction of poly-(A)-length causes alterations in spatial structure of mRNA, and associated proteins and cations Mg++ become accessible to celite absorption. Heating promotes melting of secondary structure, already initiated, and increases the efficiency of mRNA stabilization by celite. Interpreting the facts interact celite with mRNA in vitro and stabilization of mRNA in vivo by cycloheximide with a modern point of view can be considered with the position research of the phenomenon of RNA interference
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Description
Industrial horticulture assumes the most effective use of the potential of varieties. One of the key factors determining the yield of garden plantings is the effectiveness of pollination. To obtain the maximum yield, it is necessary to ensure maximum pollination during the flowering period. For this reason, much attention has been paid to the selection of pollinators. Crab-apple forms are promising for use as pollinators, so this work was aimed at identifying the most common alleles of the self-incompatibility gene in the crab-forms using the molecular genetic method of analysis. The object of the study was 29 apple-tree creams and 3 elite selection forms. They carried out the molecular genetic identification of alleles S2 and S10, which are among the most common apple trees in the world gene pool. Allele S2 was identified in 16 samples (14 forms and 2 elite selection forms), while S10 allele in one sample (elite form 12/2-20 (24-28)). Data on the allelic composition of the S gene in the samples studied are of value for the formation of a genetic passport on the compatibility of the studied samples of apple with modern industrial varieties
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NUTRIENT MEDIUM FOR INDUCTION GEMMOGENESIS TO CREATE SOMATIC CLONES OF TEA PLANTS IN VITRO CULTURE
Description
The article presents the first results of studies of somaclonal variability, which take place during cultivation of tea plants tissues and organs in vitro culture. As a starting material, there was used morphogenic callus, isolated from the basal part of tea microshoots, because callus increases somaclonal variability. An optimized protocol of the nutrient medium for induction gemmogenesis to product somatic clones of tea plants in vitro culture was developed. Morphogenesis calluses, initiated from the basal part of tea microshoots and subcultured on the nutrient medium with 6 – BAP – 2,5 ml + gibberellic acid – 1,0 ml + Tidiazuron – 4,0 ml + Tryptophan – 1000 mg, distinguished by high rates of induction of gemmogenesis – 63,3 %. The article studies the effect of exogenous growth regulators on morphological and growth indices of tea callus culture in vitro
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Description
The pathogenic agent of apple scab disease, Venturia inaequalis (Cooke) Winter, causes significant damage to the industrial production of apples. Studying the pathogen in pure culture is important for solving the theoretical and practical issues of its biology. The sporulation ability of the Venturia inaequalis laboratory culture is an important diagnostic feature in morphological culture analysis, in the test for sensitivity to fungicides, when creating a collection inoculum for an artificial infection. We have studied the morphological features of conidiogenesis of pure V. inaequalis culture, such as the location of conidiogenic structures and their form. For the first time in the laboratory culture of the pathogen, sporulation in the thickness of agar on the substrate mycelium was demonstrated. Conidiogenesis proceeded according to the blastic-annellidic type. Depending on the location of the conidiogenic structures on the aerial or substrate mycelium, their morphology was different. Conidiogenic areas in the substrate mycelium could be observed with the unaided eye, in the form of hyphal grit, while they were conidia conglomerations in each annelid. Annellide had a curved shape. On the aerial mycelium, annelids were straight and always had only one conidium. Differences in the morphology of conidiogenic structures are supposed to be related to the physical conditions of the environment in which sporulation takes place. In the agar, each mature conidium remaining at the apex of the annelid interferes with the formation of the next one, which results in its bending. The fixed arrangement of conidiogenic structures and forming conidia in the thickness of agar allows the use of substrate sporification for model studies of the conidiogenesis process
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