Akulevich O.V., Oryabіnska L.B., Dugan O.M.
The Growth Kinetics of Lactic Acid Bacteria Genum Lactobacillus on Nutrient Media with Different Sources of Carbon and Nitrogen Nutrition
P. 7–11.
Fig. 6. Tabl. 3. Refs.: 8 titles.
The study assesses the possibility of using biotechnology probiotic soy and glucose-pyruvate culture media, which contain different sources of carbon and nitrogen. When choosing nutrient media, we take into account the end product cost, which can be reduced by decreasing the cost of medic components and simplifying its preparation. We investigate five strains of lactic acid bacteria p. Lactobacillus serving the basis of a new probiotic. We propose the media composition based on soy milk and determine the optimal growth condition of lactobacterium: cultivation temperature – 37 °C, the inoculum dose to the medium volume – 5 %, pH – 7,0. The soy medium provides a high level of biomass accumulation of lactic acid bacteria. Therefore, it can be effectively used in the technology of food additives and food functionality products, containing the lactic acid bacteria genus р. Lactobacillus.
Keywords: lactobacterium, growth medium, culture conditions.
Buchalo А.S., Dzygun L.P., Linovytska V.M.
Isolation of Higher Basidiomycetes Prospective Producers of Biologically Active Substances in Pure Culture and Their Long-Term Storage
P. 12–17.
Tabl. 1. Refs.: 23 titles.
In this paper, we select methods and conditions for isolation of pure culture and long-term storage of three basidiomycetes species Schizophyllum commune Fr., Laetiporus sulphureus (Bull.) Murrill and Polyporus squamosus Huds.: Fr., which are promising producers of biologically active substances nowadays. We establish that the most effective methods of transferring strains in pure culture for S. commune was selection from spore material, and for L. sulphureus and P. squamosus – from basidiomes. 13 strains S. commune, 13 strains of L. sulphureus and 7 strains of P. squamosus are isolated from environmental conditions by using selected effective methods. We propose conditions for long-term safe strains keeping. Agar wort and temperature +4 °C are the best conditions for cultures of investigated species for 12 months and more. For 6 months of storage it is possible to use potato-glucose agar medium. The proposed methods allow keeping strains under industrials conditions without the loss of biological and technical specificity.
Keywords: higher basidial mushrooms, pure culture, Schizophyllum commune, Laetiporus sulphureus, Polyporus squamosus, producers of biologically active substances.
Galkin O.Yu.
Development of improved method of Isolation and Purification of human IgE
P. 18–23.
Fig. 4. Tabl. 1. Refs.: 22 titles.
We aim at creating and evaluating the acceptability of improved methods of isolation of high purity human IgE suitable for use in highly sensitive immuno-analytical methods. To this end, we generalize physicochemical and biological properties of immunoglobulins of different classes and analyze key methodological techniques used for isolation and purification of human IgE (ion-exchange chromatography on DEAE-cellulose, gel filtration on Sephadex G-200 and S-300 Sephacryl different options immunoaffinity chromatography). In addition, we justify circuit isolation and purification of human IgE based on own research data, as well as on other authors’ data. The technique is based on combination of the following methodological techniques: sequential removal of serum human IgG (by affinity chromatography on protein G), human IgA and IgM removal (using immunoaffinity chromatography based on sorbents with anti-IgA and anti-IgM monoclonal antibodies), allocation of human IgE by dual-gel filtration on Superdex 200. In addition, we perform the quality control of IgE by immunodiffusion for Ouhterloni and electrophoresis in polyacrylamide gel in reducing conditions. Using the proposed scheme, we obtain human IgE high purity. The human IgE output after all treatment phases is about 42 % of the initial amount of immunoglobulin E in the serum.
Keywords: human IgE, monoclonal antibodies, gel filtration, affinity and immunoaffinity chromatography.
Garda S.O., Danylenko S.G., Lytvynov G.S.
Resistance Determination of a Probiotic Strain Bacteria to Antibiotics
P. 24–27.
Fig. 1. Tabl. 1. Refs.: 10 titles.
The objective of research is to determine sensitivity of a probiotic strain to a number of antibiotics which are frequently used in the veterinary practice. To that end, we employ disk-diffusion method in the MRS-agar and used standard antibiotics-soaked paper discs. The results interpretation conform to literary sources. Specifically, Lactobacilus rhamnosus; L.acidophilus; L.brevis; L.paracasei ssp. paracasei; L.casei; L.delbrueckii subsp. bulgaricus; L.helveticus; Bifidobacterium gallinarum; B.bifidum; B.longum; B.infantis; B.adolescentis are extracted from various natural sources and identify to that stem. Relying on morphological, cultural and physical-biochemical properties, we determined species belongings of the isolated strains. Analyzing the obtained data, we can conclude that cultures L.rhamnosus, L.аcidophilus, L.brevis and B.gallinarum, B.bifidum are the most stable to main groups of antibiotics and that’s why they are prospective for using as a complex probiotic preparation in biotechnology.
Keywords: microflora, strains, bacteria, probiotics, antibiotics, poultry.
Gorobets O.Yu., Gorobets S.V., Gorobets Yu.I.
Biomineralization of Intracellular Biogenic Magnetic Nanoparticles and Their Expected Functions
P. 28–33.
Refs.: 41 titles.
The purpose of this paper is to analyze the similarity between proteins of MI MTB and organisms genomes of three main kingdoms: bacteria, archea and eukaryotes for revealing the joint genetic basis of biomineralization of intracellular biogenic magnetic nanoparticles (IBMN). In addition, the research objective is to estimate the energy of paramagnetic and efficiently paramagnetic energy of cluster components compared with their thermal motion energy for establishing the physical mechanism of possible influence of nonuniform in a magnetic field of IBMN on cell metabolism. Using methods of bioinformatics, we demonstrate there is a common genetic regulation of the biomineralization of IBMN in various organisms. Also, we reveal that paramagnetic and efficiently paramagnetic energy of the cluster component is greater in the magnetic field of IBMN than heat energy of their motion. Thus magnetic fields of IBMN can regulate transport processes in a cell. Therefore, IBMN are intracellular magnetic nanomachine for regulating transport processes in cells including reactive oxygen species production, cell-mediated immunity, cellular signal transmission, cellular receptor, biosynthesis of proteins, tactor and olfactory receptor, sensoring of oxygen pressure and etc.
Keywords: intracellular biogenic magnetic nanoparticles, bioinformatics analysis, magnetic field, transport processes in a cell, reactive oxygen species.
Gorobets S.V., Gorobets O.Yu., Demianenko I.V.
Ferritine and biomineralization of biogenic magnetic nanoparticles in microorganisms
P. 34–41.
Fig. 3. Tabl. 2. Refs.: 43 titles.
In this paper, we verify the hypothesis on obligatory participation of ferritin molecules in the biomineralization process of biogenic magnetic nanoparticles assuming that the genetic mechanism of biogenic magnetic nanoparticles is consistent for prokaryotes and eukaryotes. Using comparative genomic methods, we seek to reveal whether all the magnetic bacteria have ferritin genes in their genome. Well known proteins (ferritin and ferritin-like proteins) are compared with compiling magnetotactice bactria genomes using the blastn “BLAST on-line” under standard program parameters. This program is free software presented by National Center of Biotechnological Information. We establish that the biogenic magnetic nanoparticle biomineralization in eukaryotes and prokaryotes is not connected with availability of ferritin and ferritin like-proteins. Although we show the ferritin coagulation impossibility in Escherichia coli under the exposure of magnetic field with voltage which is enough for coagulation of biogenic and exogenous magnetic nanoparticals in cells by scanning probe microscopy method. Since protein contains ferrihydrite (antiferromagnet) crystals, magnetic fields of moderate voltage can change nanostructure localization of ferrite biogenic and exogenous magnetic nanoparticles, but cannot cause the ferritin molecules agglomerates formation.
Gorobets S.V., Karpenko Yu.V., Kovalev O.V., Olishevsky V.V.
Application of Magnetically Labeled Cells S. Cerevisiae as Biosorbents at Treatment Plants
P. 42–47.
Fig. 2. Tabl. 2. Refs.: 11 titles.
This paper studies the sorption capacity of magnetically labeled biosorbents – yeast cells Saccharomyces cerevisiae – to remove iron ions (II). The study is conducted on model solutions and wastewater samples from Slavutych, Chernihiv region. We obtain magnetically treated biosorbents by modifying Saccharomyces cerevisiae baker yeast by magnetite nanoparticles. We perform modification by mechanical and multivertex magnetohydrodynamic mixing (MHDM) of yeasts’ suspensions with magnetite nanoparticles. This paper presents the sorption isotherms of Fe(II) ions by magnetically labeled yeasts and electrokinetic potential of obtained biosorbents. We show that the sorption capacity of magnetically labeled yeast cells with magnetite nanoparticles, attached with multivertex MHDM, regarding iron ions is not reduced compared with biosorbents produced by mechanical mixing. We uncover the electrokinetic potential of magnetically labeled biosorbents before biosorption of Fe(II) cations. In addition, we reveal that the decrease of electrokinetic potential of magnetically labeled biosorbents suspension causes the reduction of its sorption capacity.
Keywords: magnetically labeled yeasts S.cerevisiae, sorption capacity, zeta potential, magnetohydrodynamic mixing, waste water.
Dekhtiarenko N.V.
Production of Enzymic Preparations in Ukraine
P. 48–58.
Tabl. 1. Refs.: 26 titles.
In this paper, we analyze the modern state of production enzymic preparations in Ukraine. Based on the source, enzymic preparations are classified as industrial (produced from microbal raw material) and medical (produced mainly from animal raw material). According to the data of Abercade Consulting, we present the growth dynamics of global market of enzymic preparations. Specifically, we show that the enzymic preparations production in Ukraine greatly depends on import. We determine leading enzyme producing companies, which import prodcuts to Ukraine and CIS countries. Possible ways of implementing the strategy of import replacement are outlined in microbiological industries taking into account basic principles of the generalized world experience. We specify key modern industrial and agricultural areas where enzymic preparations are to be used. Moreover, we list producers and developers of industrial and medical enzymic preparations in Ukraine. In addition, we briefly describe their enzymic products. This production is systematized based on composition and area of application. Currently, enzymic preparations production in Ukraine should be further developed.
Keywords: industrial enzymic preparations, medical enzymic preparations, producent, biopharmaceutics, microbiological industry, import replacement, industries of national economy.
Klechak I.R., Bisko N.A., Mytropolska N.Yu., Antonenko L.O.
Impact of Biogenic Metals Citrates Obtained by Aquananotechnology, on Growth and Biosynthetic Activity of Medicinal Mushroom Trametes Versicolor
P. 59–64.
Fig. 4. Tabl. 1. Refs.: 16 titles.
We conduct the comparative study of the impact of biogenic metals citrates such as zinc, magnesium, iron obtained using nanotechnology, on growth of mycelium and biosynthetical activity of medicinal fungi Trametes versicolor at their cultivation in a liquid medium. To characterize the biosynthetic activity, we determine mass fraction of organic acids, exopolysaccharides concentration of phenol-sulfate method, the protein content by Lowry, cellulolytic activity in carboxymethylcellulose (CMC-activity) and filter paper (FP-activity). We select concentration of citrate biogenic metals (0,3 g/dm3), whose use contributed to a higher concentration of biomass T. versicolor by 2,5 times. We demonstrate that citrates of magnesium and zinc stimulated production of T. versicolor biomass, citrates of magnesium increased the protein content and CMC-activity, the iron citrate promoted the exopolysaccharides synthesis of T. versicolor. We determine the use of essential biometals nanocitrates in the nutrient medium positively effects biosynthetic properties of the medicinal mushroom T. versicolor. It reveals an opportunity to modify the macro-and microelement composition of mushroom mycelium in the future.
Kuzmenko A.V., Marynchenko L.V., Shcherbak N.L., Vasilenko M.Yu., Kuchuk M.V.
Creation of Lettuce Transgenic Plants Carrying Gene of the Mycobacterium Tuberculosis Antigens ESAT6:Ag85B Fusion Protein
P. 65–69.
Fig. 4. Tabl. 1. Refs.: 18 titles.
Transgenic plants are promising and potentially safe tools to produce edible vaccines. Passive immunization by oral delivery of Mycobacterium tuberculosis antigens expressed in transgenic plants seems to be the perspective strategy to combat tuberculosis. In this paper, we discuss the generation of lettuce (Lactuca sativa) transgenic plants carrying the fused gene of Mycobacterium tuberculosis antigens ESAT6:Ag85B. By employing Agrobacterium mediated transformation method, transgenic plants are obtained. Vectors containing gene esxA fused with fbpB gene are used. Plasmid vectors also contain selective genes of neomycin phosphotransferase II (npt II) or phosphinothricin acetyl transferase (bar). Stable transgenic plants are selected. By using PCR analysis, we confirm the presence of target and selective genes in plants genome. Rooted plats are transferred to soil in the greenhouse for further experiments.
Keywords: lettuce transgenic plants, edible vaccines, ESAT6:Ag85B antigens of Mycobacterium tuber-culosis, Agrobacterium mediated transformation.
Maltsev A.Yu.
Mathematical and Programming Models of Coexistence of Two “Predator–Prey” Type Populations
P. 70–74.
Refs.: 5 titles.
It is a theoretical investigation in the field of modeling of numbering populations. We analyze different models of populations interactions and find essential imperfections of these models. We propose the mathematical model of interaction of the simplest population structure interaction. This model takes into consideration the phenomenon of the predator satiety under conditions of sufficient prey. This phenomenon stipulates that the predator does not eat more than it needs for satiation. The classical model ignores the predator’s satiation. We check the adequacy of our model by using simulation. We construct the flexible programmed environment. This environment allows us to simulate the interactions between populations. This environment can be used for studying very complicated structures that consist of many predator types. We analyze and compare calculation results by the mathematical model and the programming model. Our mathematical model is adequate.
Keywords: mathematical modeling, simulation, the predator-prey system, prediction of population dynamics.
Mel’nick V.M.
A Gas-Lift Bubble-Type Vehicle
P. 75–77.
Fig. 2. Refs.: 5 titles.
The purpose of research is to analyze the operation of gas-lift bubble-type vehicle and clarify the nature of energy concentration areas of working liquid fluctuation motion under the impact of external acoustic radiation. The effect of cultural liquid indignation inside the vehicle’s working volume has an indisputable advantage. This effect can be achieved without mechanical mixing devices and technological deficiencies arising out of their use. The construction of areas of energy concentration as confocal cylindrical caustic surfaces to the internal surface of bubble-type vehicle is caused by the present aberration of sound-waves, generated in the casing, as well as by the construction of the proper wave-size vehicle. In addition, the amount of energy concentration areas of working liquid motion can be increased under certain conditions at the expense of additional flat radial caustic surfaces. Totally, the dynamic state created eliminates the stagnant areas presence, dramatically increases the heat-mass exchange efficiency and the produce quality. Therefore, the coincidence resonance is the operating element of gas-lift bubble-type vehicle.
Keywords: bubbling vehicle, working liquid, ultrasonic emitter.
Sorochenko V.F., Sorochenko O.V., Veselsky S.P., Kuzmіnsky E.V.
Using Species Molecular Features of Vascular Plants in Modern Pharmaceutical Biotechnology
P. 78–83.
Refs.: 28 titles.
The paper offers promising investment destination for addressing VI-th biotech level – network biopharmaceutical local associations, “the principle of cluster triangle” based on intellectual investments in conservation three-dimensional biological activity structures and use of information capacity in the pharmaceutical nanoscale lignin components of vascular plants. We further develop the well-known concept of “general adaptive environment capactiy” or “environment carrying capacity” in terms of the plants’ information capacity – the information contained in nanostructures of plant biopolymers and give them value suitable for use in biotechnology in natural or artificial environments. We justify that it is reasonable to use nanostructures lignin in pharmacology in the study of functioning mechanisms of the digestive tract and development of their correction mehods. Finally, we define that biotechnological production and applications in pharmacology enterosorbents information capacity of nanoscale components lignin vascular plants are prospective directions.
Keywords: lignans, nano dimensions, evolutionary information, sorbents, pharmacology.
Ushanov Yu.A.
Hypothesis about the Use of Ergot Sclerotia in the Old Russian Iconography
P. 84–92.
Fig. 12. Refs.: 21 titles.
This article shows the importance of research on the nature of the materials used in the ancient iconography that gave a special glow of pure colors and the luminosity of the faces to the icon created in the XIV–XV centuries. The approach to use such materials for the icons was lost by the old masters in the second half of the XVI century and nowadays it is considered to be the greatest riddle of the Orthodox icons. There are almost no scientific publications discussing this issue. The authors have shown that the composition of the paint layer used in the old Russian icons consist from the poorly-explored natural plant materials on the basis of clavus, which have high optical activity and reflect the light in the visible range. The authors have deduced that the ancient iconographers mainly used yolk of the egg as binding substance, which is diluted with bread kvass with particles of ergot sclerotia (Secale cornutum). The results of the experimental studies confirm the hypothesis about the presence of transparent paints made from crystalline mineral pigments (cinnabar, hematite, lazurite, azurite) particles of the clavus, which have high optical activity and reflect the light in the visible range. In the paint layer of the ancient icon the light beam, reflected from the flakes of clavus, sequentially passes through the colorful layers and is repeatedly refracted by lots of crystalline particles. This creates the effects of image depth, inner glow and the play of light.
Keywords: ergot sclerotia (Secale cornutum), old Russian icons, optical activity, transparent paints.
Khrokalo L.А., Оbushenko Т.І., Pererva Ie.S., Коzlovets О.А.
Volumetric Estimation of Biogas Content
P. 93–99.
Fig. 1. Refs.: 6 titles.
In this paper, we develop the method of volumetric analysis to estimate biogas content due to using the gas analyzer (Gas Analyser Chemical Laboratorial-1). We propose the list of absorbing chemical solutions and sequence of their application, notably solution of 50–60 % sulfuric acid – for ammonia absorption; saturated solution of I2 in 0,1 М water solution of KI – for hydrogen sulphide absorption; and solution of 35 % potassium hydroxide – for carbon dioxide absorption. Catalytic oxidations of methane and hydrogen should be conducted together at the temperature of +900…+950 °С in electric furnace equipped by thermal couple and automatic temperature controller. We measure biogas content obtained in the laboratorial bioreactor by co-fermentation of pig manure and apple residue to test the device and to appraise the gas analyse method. We also present the protocol of biogas pattern measurement. The biogas content obtained from the laboratorial bioreactor has such residual moisture and NH3 – 6,6 %; Н2S – 4,2 %; СО2 – 21,4 %; H2 – 1,08 %; CH4 – 65,22 %; N2 – 1,49 %. The simple device construction and reduced analytical equipment costs compared with other physical-chemical and physical methods of gas analysis are the advantages of gas analysis volumetric method.
Keywords: biogas, gas analyzer, method of volumetric analysis, bioreactor.
Chugunova K.O.
Antagonistic Activity of Pseudomonas fluorescence 2303 Strains to Fitopathohenic Microorganisms
P. 100–103.
Tabl. 2. Refs.: 10 titles.
In this paper, we study the antagonism of Pseudomonas fluorescens 2303 strain on pathogenic bacteria’s and fungi’s. This strain inhibited the development of P.syringae pv. syringae 8511, P.syringae pv. atrofaciens 9400, Xantomonas campestris 8003b, Clavibacter michiganensis 102 – stunting zones were 20–40 mm. Strain P.fluorescens 2303, unlike the product haupsyn, inhibited the growth of pathogenic bacteria such as Pectobacterium carotovorum 8982 and 8626 Agrobacterium tumefaciens. P.fluorescens 2303 strain was highly active against phytopathogenic fungi and was on average two times more active than the strain of plant protection product – gaupsin. In particular, the inhibition index of root rots caused by Gaeumannomyces graminis var. tritici 10Z is 9,4 times higher than the corresponding value for gaupsin. The research into P.fluorescens 2303 strain is promising for its applying in agriculture for comprehensive plants protection of plants against pathogenic fungi and bacteria, as well as for developing a product based on this strain.
Keywords: antagonism, Pseudomonas fluorescens, phytopathogens, plant protection.
Barbash V.A., Ostapenko A.A.
Influence of Amphoterous Polymer Resin on Indexes of Dehydration of Pulp and Paper Quality
P. 104–107.
Fig. 3. Tabl. 2. Refs.: 10 titles.
Influence of amphoterous polymer resin “Ultrares 200” on forming process and strength properties of paper from wastepaper was investigated. It was established, that increasing of beating rate of pulp leads to decreasing of pulp dehydration rate. It was concluded, that grinding shortens and partially fibrillates fiber, increasing their surface leading to better swelling and retention of water by fibers. It was shown, that increasing pulp temperature and charges of amphoterous polymer resin “Ultrares 200” accelerates pulp dehydration rate by the means of interaction of resin’s cationic groups with hydroxyl and carboxyl cellulose groups creating fiber aggregates. It accelerates process of pulp dehydration, promotes pulp components retention at wire of paper machine and increasing its productivity. It was found that addition of “Ultrares 200” in quantity 0,2–0,6 % from absolutely dry fiber mass can increase for 0,5–23 % strength properties of paper from wastepaper.
Keywords: chemical supportive substances, dehydration rate, quality index of paper.
Vasiliev O.O., Muratov V.B., Duda T.I.
Calculation of Thermodynamic Properties of Graphite and Grapheme Based on Spectroscopic and Elastic Characteristics
P. 108–113.
Fig. 1. Tabl. 1. Refs.: 15 titles.
In this paper, we calculate the low temperature (0–300 К) heat capacity, enthalpy, entropy and reduced Gibbs energy of graphite and graphene. Specifically, we calculate the temperature dependencies of heat capacity using literature sources on phonon spectrums of materials and elastic properties of graphite as input values. We show that thermodynamic characteristics of graphene substantially exceed those for graphite. Specifically, we explain these differences by features of the graphene phonon spectrum. By analyzing the differences between enthalpy values, we show that graphene as compared to graphite has a higher level of internal energy. The calculated values of reduced Gibbs energy made it possible to assess the ratios of reactivity and probability of formation during synthesis of graphite and graphene. We concluded that using calculation results during when studying thermodynamic properties of real specimens of carbon structures with layered hexagonal structure has some advantages.
Keywords: graohite, graphene, heat capacity, thermodynamic properties, enthalpy.
Dontsova T.A., Bredykhin I.V.
The Photocatalysis Mechanism on TiO2 Surface
P. 114–118.
Tabl. 2. Refs.: 21 titles.
We discuss the mechanism of heterogeneous photocatalysis (formation of electron-hole pairs) on the TiO2 surface (initiated by ultraviolet radiation) as well as the stage of the photocatalytic process. As a result, we determine that to increase the efficiency of the photocatalytic process in the visible light range it is necessary to reduce the band gap of catalyst based titanium oxide (IV). Based on literature data, we find that the structurally-sorption characteristics such as crystal size, the porosity (specific surface area), the degree of crystallinity mainly affect the photocatalytic activity. We analyze ways of modifying catalysts of titanium oxide (IV), which will reduce the band gap and increase the catalyst photocatalytic activity in the visible light range. We select effective methods of modifying titanium (IV) oxide (metal coating on the surface of TiO2 and creation of nanocomposites (heterostructures) based on TiO2) for further studies.
Keywords: heterogeneous photocatalysis, titanium oxide (IV), electron-hole pairs, chemical modofication, band gap.
Dulneva T.Yu.
Microfiltration Cleaning from Fe3+ Ions of Scourages Deferrization Stations
P. 119–122.
Fig. 4. Refs.: 15 titles.
Currently, baromembrans methods based on polymeric membranes are used for water treatment from Fe3+ ions. However, such membranes are destroyed under the impact of hydroxo-complexes of Fe3+ ions contained in water. Therefore, we do the research into basic regularities of model scourages cleaning from Fe3+ ions using microfiltrations titanic tubular membranes that are more persistent and have more long-term operating life than polymeric ones. As a result, we define technological parameters providing effluents cleaning from Fe3+ ions of ceiling standards concentrations for discharge into the sewer: working pressure of 0,05–0,5 МPa, the concentration of Fe3+ ions in the initial water 4,0–56,0 mg/dm3, рН of the water – 2,85–6,2. At the same time the following results were obtained: the coefficient of Fe3+ ions delay – 99,0–99,9 %, the specific productivity of membrane – 0,03–0,17 м3/(м2·h) and residual concentration of these ions in a filtrate 0,01–1,75 mg/dm3. These results are obtained due to formation of titanic tubes of dynamic membranes on the surface from hydroxo-complexes of Fe3+ ions regarding which these membranes demonstrate a greater delay than to the ions. Thus, we propose to use modified titanium membranes for cleaning scourages of deferrization underwater stations from iron ions.
Keywords: cleaning scourages, microfiltration, titanium membrane, ions of iron, hydroxo-complexes.
Lobanov О.Yu., Sviderskyi V.А.
Exploitation Propperties of Cellular Concrete with Modificated Surface
P. 123–126.
Tabl. 4. Refs.: 7 titles.
The purpose of work consists in development of impregnating with compositions on the basis of siliconorganic matters of modified by thermoplastic polymers for the impregnation of cellular concrete. Treatment the prepared compositions allow to promote operating properties of cellular concrete wares. The decision of this task was arrived by research of influence of surface retrofitting of cellular concrete wares by impregnating with compositions of different composition and concentration. Twocomponent systems which contained polymethylphenylsiloxane varnishes modified by polymethylenoxide in solution of toluene. The cellular concrete was leaked by prepared solutions and upon termination of modification process the basic physic-mechanical properties of wares was determined. It is set after they got results, that the most increase of operating properties of cellular concrete takes place at saturating with compositions with optimum correlation and concentration of components in solution.
Keywords: cellular concrete, retrofitting, polymethylenoxide, impregnation, water absorption, tensile strength, depth of impregnation, optimum concentration.
Makarov A., Klischenko R., Konoval A.
The Impact of the Composition of Aqueous-Alcohol Dispersion on Electrokinetic and Rheological Properties of Composite Coal-Water Suspensions
P. 127–131.
Fig. 5. Tabl. 1. Refs.: 8 titles.
In this work, we obtain sedimentary resistant aqueous suspensions of coal containing waste products of alcohol production – fusel oil and also wastewater with organic compounds. To this end, we study influence of alcohol aqueous solutions and modification of coal surface under the impact of anionic polyelectrolites on electrokinetics and rheological properties of coal aqueous suspensions. The boll mill technique is used to make dispersions, while electrochemical methods and viscosimetry are utilized in the research. Thus, we determine the influence of alcohol aqueous solutions on coal aqueous suspensions and define the anionic polyelectrolites in the alcohol aqueous dispersions as rather effective agents for modifying surface coal particles. Finally, we obtain sedimentation and aggregation-resistant water-coal suspensions due to formation of three-dimensional spatial grid structure and spatially oriented polyelectrolyte molecules.
Keywords: wastewater, water coal suspensions, composition, alcohols, polyelectrolytes, brown coal, anthracite, electrokinetic potential.
Medvedev R.B., Merdukh S.L.
Water Chemistry and Mathematical Modeling of the Second Circuit of the NPP with PWR-1000
P. 132–139.
Fig. 2. Tabl. 2. Refs.: 12 titles.
This article discusses the current state of issues of the water chemistry support at operating NPP with the pressurized water reactor with determined capacity of 1000 MW (PWR-1000). We provide an overview of technological features of the power unit with PWR-1000. Methods and tools to ensure the water chemistry of the second circuit of the NPP are analyzed. Furthermore, we establish that performance of the normalized quality indicators of feed water can not completely eliminate deposits formation on heating surfaces. We reveal that existing plant control systems should be improved for the optimum water chemistry needs. New systems of automation of technological modes of the second circuit unit should be introduced. It is impossible to create these systems without construction of a mathematical model of the process. Therefore, we develop mathematical models of basic water chemistry of the second circuit blocks distinguished by the system analysis of the technological power scheme. We show simulation results of PWR-1000 second-circuit scheme by using MatLab Simulink environment techniques. We prove that the obtained mathematical model is adequate and can be used when developing strategies to control the second circuit of NPP with PWR-1000 reactor.
Keywords: nuclear power plant, water chemistry, pressurized water reactor, mathematic modeling.
Pylypenko I.V., Makovetskyi O.L., Kornilovych B.Yu.
Structure Formation in Dispersions of Montmorillonite in the Presence of Quaternary Ammonium Salts
P. 140–144.
Fig. 2. Refs.: 16 titles.
The aim is to study the influence of cationic surfactants – quaternary ammonium salts – for structure formation in montmorillonite suspensions by studying the rheological and colloidal-chemical properties of such systems. Relying on x-ray diffraction analysis we identify surfactant molecules close to a parallel position relative to the basal surface of mineral with the interlayer space of 1.6 nm. By using rheometry we obtain flow curves and corresponding values of boundary shear stress for dispersions of montmorillonite in the presence of cationic surfactants. We show the extreme character changes of rheological characteristics of montmorillonite dispersions depending on the concentration of surfactant. Highs in the curves of boundary shear stress on the concentration of surfactant correspond to formation of a continuous mesh between particles with “edge–face” orientation. We demonstrate that the use of cationic surfactants changes the shear stress to maximum (15 Pa) in the concentration of surfactant 1 mmol/dm3, and gradually decreases to almost zero with a further increase surfactant content. These results lay foundation for determining the optimal parameters of porous heterostructures synthesis and regulation of their properties by changing the hydrophilic-hydrophobic balance of source systems.