Development of Improved Method of Obtaining of Fc-fragments of Human IgM /Galkin O.Yu. // Research Bulletin of NTUU "KPI". — 2012. — № 3. — P. 7–11. Fig. 6. Refs.: 17 titles.
The aim of work was to develop the improved methods of obtaining and allocating Fc-fragments of human IgM. To achieve this goal IgH hydrolysis with subsequent purification (Fс)5m-fragments was optimized. The improved method for obtaining Fc-fragments of IgM provides papain hydrolysis of immunoglobulin in the nitrogen environment for 30 minutes allowing to achieve maximum output of Fcm-fragments without their further degradation: isolation and purification of Fcm-fragments by two-stage gel filtration on sephacryl S-300; control the purity of the target product in electrophoresis in polyacrylamide gel with SDS and immunodiffusion for Ouchterlony. By employing the proposed scheme, we can obtain Fcm-fragments of high purity. Outcome of Fsm-fragments after all stages of purification was about 15 % of the initial IgM amount in the preparation. Molecular weight of Fcm-fragments was approximately 95 kDa.
Effect of Alkali Metals Ions on Growth and Biomass Accumulation of Lipid (Metabolism) in Chlorella Vulgaris /Golub N.B., Buncha V.Yu. // Research Bulletin of NTUU "KPI". — 2012. — № 3. — P. 12–17. Fig. 6. Tabl. 1. Refs.: 11 titles.
In this paper, we analyze the influence of nutrient medium on the growth of algae biomass species Chlorella vulgaris. By employing methods of microscopy, one- and two-dimensional thin layer chromatography, as well as by using mathematical methods of interpolation and approximation of data, we show that reduction of nitrogen concentration, increase of salinity and concentration of potassium drastically decrease the biomass growth. The amount of lipids increases to 10–15 % under nitrogen deficiency, moderate salinity (2,5 g/l NaCl) and in the joint action of both factors. The content of fatty acids and the number of minor factions also increases. At concentration of NaCl 2,5 g/l the content of 16:0 fatty acids increases, while the percentage of eicosapentaenoic acid 20:5w-3 is at the minimum level and increases by reducing the salinity to optimal level. The increase of potassium ions concentration does not promote the accumulation of lipids in the biomass of microalgae Chlorella vulgaris. The increase of salinity (2,5 g/l NaCl) can reduce energy costs for algae cultivation by increasing the amount of lipids within less period of time.
Genetic Regulation and Phenotypic Expression of the Properties of Biogenic Magnetic Nanoparticles in Magnetotactic Bacteria and Human /Gorobets S.V., Gorobets O.Yu., Sivenok D.V., Chyzh Yu.M. // Research Bulletin of NTUU "KPI". — 2012. — № 3. — P. 18–23. Tabl. 2. Refs.: 26 titles.
By employing the bioinformatics methods, we consider the similarity between the genes of magnetosome island of magnetotactic bacteria and human genes for establishing the degree of homology and determination of functional class of proteins. We analyze the most meaningful coincidences between the genes of magnetosome island of bacteria of Magnetospirillum gryphiswaldense and human genes. We uncover the essential smoothing mainly among proteins of functional class. The process of biomineralization of magnetite in МТB, namely MamВ, MamЕ, MamА, MamN, MamО, MamМ can’t be conducted without these proteins. They have the well known common functions or belong to the same family. The analysis of homologues of regulator proteins (what regulate a form, size and amount of parts of Fe3O4, and also regulate formation of chain and magnitosome vesicule) show that only one protein of MamК can be a hypothetical homologues with the human proteins. The research results demonstrate there is no class of regulatory proteins in humans. There is strict control on the size of genetic and structural characteristics of biogenic magnetite.
Developing Nutrient Mediums on the Basis of Hydrolysates of the Soybean Flour for Cultivating Representatives of Lactobacillus sp. /Dekhtiarenko N.V., Dugan А.М. // Research Bulletin of NTUU "KPI". — 2012. — № 3. — P. 24–29. Tabl. 6. Refs.: 10 titles.
The paper considers the second stage of developing the laboratory technology of sanitary sour-milk products on the basis of the soybean flour. It was produced according to the novel national technology ЕСОÒ. The technology is based on the special processing of seeds soybean called “seeds awakening”. As a result of biochemical transformations of matters, outer and inner decontamination of weevils take place. We select concentrations, рН optimum of operating and time length of enzymatic processing of the soybean flour by ferment preparations of the alkaline protease and protease С aimed at subsequent usage as the basis for nutrient mediums. In addition, we detect the inductive influence of hydrolysates of the soybean flour on synthesis of exogenic proteins-metabolites by cultures of lactic acid bacteria L. delbrueckii subsp. lactis LE and L. rhamnosus LB3 (IMB B-7038) has detected. The increase of protein concentration in the medium of cultivation of L. rhamnosus LB3 strain reaches 90 %. We also show adding 1 % of hydrolysates of the soybean flour of the glucose provides the maximum biosynthetic activity of cultures of the lactic acid bacteria.
Ganoderma Lucidum (Curtis) P. Karst. Submerged Cultivation Peculiarities on the Bread Crumbles Substrate /Ivanova T.S., Bisko N.A., Krupodorova T.A., Barsh-teyn V.Ju. // Research Bulletin of NTUU "KPI". — 2012. — № 3. — P. 30–35. Fig. 2. Tabl. 1. Refs.: 26 titles.
In the present paper, we investigate biomass, exopolysaccharide, phenols, organic acids, reducing and dry substances accumulation and pH of cultured broth during submerged cultivation of G. lucidum 1900 on bread crumbles. It shows the future prospects and the possibility of using this waste from the food industry in Ukraine. We demonstrate that maximal biomass and exopolysaccharide concentration can be obtained on the 15th day of cultivation (18,10 ± 0,2 and 5,2 ± 0,3 g/l correspondingly). Our research results show that different carbon sources of bread crumbles result in two pics of growth speed and reducing substances accumulation of cultured broth. According to the calculated growth speed, specific growth speed, specific substrate bioconversion efficiency and metabolic coefficient calculations, the most intensive processes of biomass production occur before the 6th day of cultivation, however maximal biomass biosynthesis speed, specific speed and productivity was before the 9th day of cultivation.
Remediation of Municipal Waste Water Biocolloid Solids Contaminated by Heavy Mеtals /Kalinichenko K.V., Nikovska G.M., Ulberg Z.R. // Research Bulletin of NTUU "KPI". — 2012. — № 3. — P. 36–40. Fig. 2. Tabl. 1. Refs.: 17 titles.
The study is devoted to the experimental substantiation for technology of heavy metals removal from contaminated municipal wastewater sludge by enhancing the activity of autochtonous biocenoses with formation of metabolites binding metals into stable water soluble complexes. We compare the efficiency of heavy metals removal from sludge of biological treatment of municipal wastewaters in bioleaching process with heterotrophic and chemotrophic biocenoses and chemical leaching. Moreover, we demonstrate the advantages of metals bioleaching process at acidogeneous heterotrophic metabolism. The efficacy of heavy metals leaching from sludge sol and swollen gel-like solid is similar, ranging from 83 (Zn) to 15 % (Cr), and follows the order: Zn > Mn > Cu > Ni > Cd > > Pb > Cr. Two variant of the technology for bioremediation of waste sludge is proposed: 1) ex situ incubation of concentrated sludge sol with carbohydrate substrates, at stirring, followed by phase separation by sedimentation and removal of fluid; 2) in situ compositing gel-like sludge solid with meadow grasses after preliminary swelling. Using conditioned sludge solids, vegetation experiments show the accelerated growth and increased yield of plants.
The Biotechnology on the Basis of the Higner Basidiomycetous Mushrooms of Genus Coriolus Quel /Klechak I.R., Antonenko L.O. // Research Bulletin of NTUU "KPI". — 2012. — № 3. — P. 41–49. Tabl. 2. Refs.: 25 titles.
In this paper, we analyze information on the medicinal properties of the genus basidiomycetous mushrooms Coriolus. Representatives of this genus have a wide range of medicinal properties such as: immune modulating, restorative, anti-inflammatory, antiviral, antibacterial, radioprotective, hepatoprotective, etc. Therefore, basidiomycetes Coriolus are effectively used in medicine, food and light industry, agriculture. This article summarizes the information on biotechnology based on basidiomycetes genus Coriolus, which are used worldwide. Medicinal products of the basidiomycetes of genus Coriolus contains purified fraction of polysaccharides extracted from the fruit bodies collected in nature or mycelium. The body of scientific literature proves that the structure of the submerged basidiomycetes mycelium does not differ from fruit bodies. Hence the biotechnology for producing functional foods and drugs on the basis of basidiomycetes Coriolus mycelium and biologically active substances extracted from it is relevant.
The Study of pH Influence on Kinetics of Carbamide Hydrolysis /Kоrchugаnоvа О.М., Аbuzarova К.R., Zaraiska О.S., Kursa N.Ye. // Research Bulletin of NTUU "KPI". — 2012. — № 3. — P. 50–55. Fig. 5. Tabl. 2. Refs.: 11 titles.
The homogeneous carbamide precipitation method is used for producing highly dispersed metal hydroxides. Carbamide hydrolysis is the limiting stage of such process. By determining the dependence of hydrolysis rate on solution pH, we choose the optimum conditions for the process. Hence we conduct the kinetic investigations of the process of carbamide hydrolysis in various original pH solutions (0,7–7). It was carried out in isothermal conditions under permanent solution evaporation. Through experiments conducted, we define such kinetic characteristics as the reaction order, the effective hydrolysis constant and the reaction rate constant. We obtain the equation for calculating the rate of carbamide hydrolysis depending on the hydrogen ions concentration. To create the optimum pH conditions for the precipitation process of metal hydroxides, we propose it is proposed to incorporate crystal seeds to mother liquor.
Experimental Determination of Optimum Parameters of Technological Creation of Bionanocomposites Based on the Interaction Between the Aliphatic Aminoacids and Carbon Nanotubes /Manilo M.V., Ar’ev I.A., Lytvynov G.S. // Research Bulletin of NTUU "KPI". — 2012. — № 3. — P. 56–60. Fig. 3. Tabl. 3. Refs.: 8 titles.
This paper studies the interaction between biological molecules and novel nanomaterials such as carbon nanotubes (CNT). The latter plays a crucial role in developing novel types of miniature devices for biological purposes. We also investigate the immobilization behavior of aminoacids in the multi-wall carbon nanotubes to create functional aminocid/CNT conjugates. Furthermore, we use spectrophotometric methods. We show that the location of adsorbate molecules on the CNTs surface depends on the alkalinity and acidity of the solution. This fact proves that the interaction has the physical nature. We also study kinetics and examine influences of pH and concentration-dependence of adsorption of these molecules onto the CNT surfaces for optimizations of immobilization processes. The results obtained can serve for purposeful creation of bionanocomposites with a given surface concentration of amino-functional carbon nanotubes by using the variation of time, pH and concentration of the adsorptive. They also further optimization of these technology processes for constructing such materials and time parameters.
Influence of Glucose Concentration in Culture Medium on Recombinant gp 120 HIV-1 Production /Ryhliuk O.M., Gorlov A.Y. // Research Bulletin of NTUU "KPI". — 2012. — № 3. — P. 61–65. Fig. 2. Tabl. 1. Refs.: 8 titles.
Contingent screening for specific serological markers of infection ranks high in HIV prophylaxis. Nowadays the most common serological screening practice of HIV is contingent testing to detect serum antibodies against the HIV using an enzyme linked immunosorbent assay (ELISA). Recombinant analogues of HIV-1 envelope protein gp 120 are widely used in all commercial ELISA test kits for HIV diagnostics. In this paper we study the production of rgp 120 in E.coli host strain. The research strategies focus on improving the cultivation techniques and manipulating the bacteria physiology. Two fed batch strategies are applied – with continuous and exponential feeding. Exponential feeding is used so that the cells can be grown at the desired growth rate (m) by programming the bioreactor software. By providing proper nutrient and operation conditions, this strategy allows us reaching a high cell concentration and achieving high yields of recombinant product.
Ways of Forming Biofilm of Microorganisms with Exoelectrogens Activity /Samarukha I.A., Bilim Yu.S., Michailenko O.A. // Research Bulletin of NTUU "KPI". — 2012. — № 3. — P. 66–73. Fig. 1. Tabl. 1. Refs.: 49 titles.
The development and enhancement of bioelectrochemical systems to produce electricity and hydrogen is a promising area of modern bioenergy. Microorganisms are the active component of bioelectrochemical process in bioelectrochemical systems. These microorganisms further the processes of degradation of energy substrate to form compounds and exocell transfer of electrons to a terminal acceptor. We analyze existing methods of biofilm formation of electroactive microorganisms depending on its species diversity and processes of formation. By applying the methods of analysis, synthesis and comparative evaluation, we show that the methods of two-step selection and consistent enrichment of the biofilm of electroactive bacteria are the most promising. Also, they do not require sophisticated equipment and procedures for implementing the process. We analyze the formation of molecular genetic biofilm and describe the dynamics of the process for the biofilm bacteria Geobacter sulfurreducens.
Alternative Components of Nutrient Mediums for Actinomycetes – Producer of Biologically Active Substances /Todosiichuk T.S., Gordeev D.A., Izdebska T.I., Jaremchuk S.M. // Research Bulletin of NTUU "KPI". — 2012. — № 3. — P. 74–79. Fig. 3. Tabl. 1. Refs.: 8 titles.
Taking into account the wide-spread of such group as actinomycetes among industrial producers, we use one of its representatives (Streptomyces recifensis var. lytіcus – a producer of a lytic enzyme complex) as a model for studying alternative components which can be utilized for optimization of nutrient mediums for actinomycetes. We study the influence of alternative components of nutrient mediums on biosynthetic processes of culture Str. recifensis var. lytіcus and define the possibility of their use for optimization of nutrient mediums for actinomycetes. The research results establish that whey can't be used as a component of nutrient mediums for the given culture. Using pea and rape flour in some cases reduces the efficiency of culture by 20–40 %. Blackstrap use increases the culture efficiency and specific activity of a product by 1,5–2 times and allows reducing the medium price by 1,3 times. Finally, we demonstrate the influence of nutrition sources on biosynthesis orientation, as well as the efficiency and economic feasibility of blackstrap use in the medium composition.
Determine the Effect of Probiotics on the Steroids Profile of Women in the Period of Menopause /Тyplynska Е.V., Оriabinska L.B., Gorchakov V.U. // Research Bulletin of NTUU "KPI". — 2012. — № 3. — P. 80–87. Fig. 4. Tabl. 2. Refs.: 15 titles.
Women have violation of sexual hormones synthesis in the period of menopause. Key manifestations of insufficient synthesis of androgens are decrease of bones density, memory worsening, diminishing of the muscular mass, violation of the ovaries functions and sexual disfunction. In modern medicine disorders of sexual hormones synthesis are corrected by the hormones therapy which has by-effects. We demonstrate that probiotic can serve as supporting therapy for women with disfunction of androgens. Efficiency of probiotic therapy was determined by the individual sensitivity of patients to medicinal products. We determine that the most drastic influence of probiotiсs was rendered on the increase of testosteron and degidroepiandrosteron concentration in the organism, and on the renewal of the normal correlation of these steroids to other hormones. These steroids are influenced by substantial changes with age so the increase of their concentration under the impact of probiotics can positively influence metabolism in organism. The obtained results make it possible to examine probiotics as supporting therapy for women in the menopause period.
Study about the Influence of Conditions of Exoelectrogenes Cultivation on Bioelectrochemical Hydrogen Evolution Process /Schurska K.O., Zubtchenko L.S., Kuzminskyy Yе.V. // Research Bulletin of NTUU "KPI". — 2012. — № 3. — P. 88–92. Fig. 4. Refs.: 10 titles.
This paper presents a brief overview of methods for obtaining hydrogen. We study the influence of cultivation conditions of exoelectrogenes on the efficiency of bioelectrochemical hydrogen production. We describe the method of two-stage anode biofilm selection, which is used for exoelectrogenes immobilization on the anode. Furthermore, we determine the impact of the applied voltage values ranged from 0,2 to 0,8 V on the process of bioelectrochemical hydrogen production using sodium acetate as a substrate. We utilize glucose, citric acid and sodium acetate to investigate the influence of substrate on bioelectrochemical hydrogen production process. By employing sodium acetate in the concentration range from 1×10-3 mol/dm3 to 35×10-3 mol/dm3, we determine the optimal concentration of carbon-containing substrate in the nutrient medium. We describe the systems and methods of conducting the experiment used to study the influence of exoelectrogenes cultivation conditions on the process of bioelectrochemical hydrogen evolution. Finally, we define the basic indicators used to evaluate the effectiveness of bioelectrochemical system.
Solvent Delignification of Kenaf and Sugar Sorghumstems /Barbash V.A., Trembus I.V., Oksentujk N.M. // Research Bulletin of NTUU "KPI". — 2012. — № 3. — P. 93–97. Fig. 2. Tabl. 3. Refs.: 8 titles.
The chemical composition of stalks of kenaf and sugar sorghum was studied. Established that the kenaf and sugar sorghumstalks contain more cellulose, pentosans, minerals and less lignin than wood. The influence of main technological parameters on the quality indexes of organosolvent pulp obtained from kenaf and sugar sorghum stems was investigated. The possibility of bleaching organosolvent pulp obtained from stems of kenaf using hydrogen peroxide without chlorinecompounds to 80 % whiteness was experimentally proved. The parameters of selectivity of lignin’s dissolution byalkali-sulphite-alcohol delignification of kenaf and sugar sorghum stems were calculated. It was found that withincreasing temperature and duration of cooking, such selectivity indexes as degree of removal of carbohydrates anddegree of delignification are increasing and selectivity index is decreasing. Efficiency of various representatives’ delignification plant materials by means of diagrams depending on the content of pulp out there residual lignin was compared. Recommended use organosolvent pulp from kenaf and sorghum sugar stems for different types of cardboard and paper products.
The Determination of Stability of Platinum Catalyst of Selective Reduction of Nitrogen Oxides /Vekshin V.O., Rodin L.M., Loboyko V.O., Docenko A.D. // Research Bulletin of NTUU "KPI". — 2012. — № 3. — P. 98–102. Fig. 4. Tabl. 3. Refs.: 6 titles.
In the article we present research results of the activity change by platinum catalyst of selective catalytic reduction (SCR) NOx from the operating time. We propose the method of determining the stability of the catalyst relying on the correlation between the size of crystallite and activity of catalysts. We demonstrate the results of deactivation velocity of different catalysts with respect to time. Based on data of fluorescence analysis and electron microscopy analysis, we demonstrate physico-chemical characteristics of the novel catalyst and samples with various operating time. We define causes of decreased activity of developed catalysts, as well as uncover the results of comparative analysis with other research data. Based on experimental data, we develop mathematical models showing how the decrease of catalysts activity depends on the crystallites size of catalytically active substance. Finally, this technique can be applied to predict the time operation of developed catalysts.
Electrochemical Sensor of Oxygen for Biological Liquids Based on Nanocrystilline /Kolbasova I.G., Linyucheva O.V., Vorobets V.S. // Research Bulletin of NTUU "KPI". — 2012. — № 3. — Zn Oxide P. 103–109. Fig. 9. Tabl. 2. Refs.: 14 titles.
In this paper, we propose to use nanocrystalline ZnO electrodes, obtained through zol-gel and electrochemical methods, as a sensitive element of dissolved oxygen sensor. We elucidate that electrodes have stable characteristics at electroreduction О2 in biological solutions. The average size of the obtained particles d makes up ~ 10 nm. We determine the quantity of electrons on the discharge stage and the total quantity of electrons, participating in restoration reaction of oxygen. Furthermore, we study the influence of environment on characteristics of the obtained electrodes and choose the material for additional electrode of oxygen sensor. Relying on the research results, we create the laboratory model of an electrochemical sensor for measuring the concentration level of oxygen in biological liquids. Taking into consideration the level of electrochemical noise, we estimate the sensor sensitivity to the dissolved oxygen ((6–15)·10–8 mol/l). The accuracy of concentration measurements О2 made up 5–8 %, speed – 5–7 s.
Physical Models of Ultrasonic Influence are in Liquid Compositions of Epoxy Polymers. Part 2. Physical Model of the Process of Ultrasonic Influence of Different Frequency /Kolosov O.Ye., Sivetskyy V.I., Sakharov O.S., Sidorov D.E. // Research Bulletin of NTUU "KPI". — 2012. — № 3. — P. 110–114. Fig. 2. Refs.: 7 titles.
Relying on the analysis of durability and operating characteristics of boundary hardened unfilled epoxy polymers obtained during ultrasonic influence with different frequencies at pressure variation on liquid epoxy compositions and their further hardening, we prove the corresponding physical model. We propose the effective parameters of the combined ultrasonic influence (frequency, amplitude, intensity, pressure) by example of shaping epoxy polymers with the form memory effect. By analyzing features of ultrasonic modification of epoxy oligomers and liquid epoxy| compositions used while shaping the reinforced polymeric composition materials, we prove the future prospects of this modification both in low-frequency and in middle frequency ultrasonic ranges. In addition, we reveal that using the surplus pressure is the important factor of increasing intensity and time reduction of the combined ultrasonic treatment.
Kinetics of Dissolution of Precious Metals in Plasma Chemically Activated Solutions /Pivovarov A.A., Vorobyova M.I. // Research Bulletin of NTUU "KPI". — 2012. — № 3. — P. 115–119. Fig. 4. Refs.: 8 titles.
This study suggests the possibility and efficiency of applying solutions, treated with the contact nonequilibrium low-temperature plasma to intensify dissolution of precious metals in cyanide leaching systems. The research results show that chemically activated plasma solutions due to the complex of peroxide and superperoxide compounds, radicals and particles formed in water during processing, have higher oxidizing properties as compared with synthetic hydrogen peroxide commonly used in the hydrometallurgical industry as oxidizing component. We define the influence of main technological parameters on the dissolution speed of precious metals in activated solutions, as well as in the synthetic hydrogen peroxide. Also, we show that the dissolution of gold and copper in both cases is characterized by transitional type kinetics. The calculated values of activation energies prove this fact. The comparison of values activation energies show the advantage of using activated solutions over adding synthetical hydrogen peroxide.
Trinuclear Complexes of Co(III) with Triethanolamine /Potaskalov V.A., Potaskalova N.I., Zul’figarov A.O., Andriiko A.A. // Research Bulletin of NTUU "KPI". — 2012. — № 3. — P. 120–126. Fig. 3. Tabl. 2. Refs.: 20 titles.
The polynuclear complexes of 3d-metals with aminoalcohols or their deprotonated forms can be catalytically active due to the availability of two close atoms of different metals connected with bridge oxygen atoms. Heterometal complexes of Co(III) can be used for synthesis of high efficient catalysts for processes with electron transfer by creating the nanostructured electrocatalytic centres on the surface using preliminary adsorption of complexes followed by pyrolysis at certain temperatures. Based on inner-complex compound of Co(III) with triethanolamine [CoHtetmH2tetm], a series of trinuclear heterometal complex compounds with 3d-metals Ме[CoHtetm2]2 (where Ме = Co2+, Cu2+, Zn2+, Ni2+) have been obtained. This type of structures corresponds to polynuclear inner-complex compounds. We also consider some possible schemes of atoms coordination in these complexes. By employing the elemental analysis and IR-spectra measurements, we prove the inner-complex character of complexes. In addition, we draw the conclusion about the СоО4N2 coordination environment of the cobalt and translocation of the nitrogen atoms in the ion [CoHtetm2]-, which serves as the complicated complex ligand. Trinuclear compounds can be used as precursors for synthesis of several cation and anion complexes, pyrolysis products, which are catalytically active on the solid carriers.
Structure Formation in the Ceramic Matrices for Immobilization of Wastes Substances /Spasonova L.M., Pavlenko V.M., Kornilovych B.Yu., Rudyy A.І. // Research Bulletin of NTUU "KPI". — 2012. — № 3. — P. 127–132. Fig. 3. Tabl. 1. Refs.: 12 titles.
The paper studies processes of structure formation at heat treatment of purification wastes of radioactive cesium waters using sorbents based on clay minerals and zeolite. We define structural and mechanical properties of simples and find the optimum conditions of their heat treatment aimed at obtaining based on crystalline structures with the most effective physical and mechanical properties. We also investigate mechanical and chemical stability of ceramic matrices formation and also strength of commitment 137 Cs in them. Physical and mechanical characteristics of obtained samples and research results of vatting processes using different aggressive media confirm high hardness of radionuclides fixation in ceramic matrices. They can hold radiocesium in safe immobilized state for a long time. It can be argued that it is possible to use ceramic technology for processing water purification precipitation, which contains clay minerals or ceolites for disposal and safe storing of water purification wastes from cesium radioactive pollution.
Structure and Morphology of Zirconium Oxide (IV) Powders Synthesiized by the Thermal Method from Different Precursors /Fedenko U.N., Dontsova T.A., Astrelin I.M. // Research Bulletin of NTUU "KPI". — 2012. — № 3. — P. 133–136. Fig. 3. Tabl. 2. Refs.: 12 titles.
ZrO2 powders were synthesized from different precursors by the thermal method: zirconium hydroxide (ZrO(OH)2) and zirconium oxalate (ZrOC2O4). In synthesized samples by XRD analysis it was researched phase composition; sample, synthesized from ZrO(OH)2, consists of, mainly, the monoclinic modification, and sample, synthesized from ZrOC2O4 – of the tetragonal modification. It was calculated crystal grates parameters of obtained ZrO2 powders by the method of XRS analysis. It was fined crystallite’s sizes: for standart, synthesized from ZrO(OH)2, and sample, synthesized from ZrOC2O4, respectively, 74,5 nm and 29,4 nm. By the methods of scanning (MIRA3 TESCAN) and translucent (ПЕМ 125К) electron microscopy it was determined morphology and minimal size of ZrO2 particles. Sample, synthesized from ZrO(OH)2, has granule structure with minimal particle size 100 nm, and sample, synthesized from ZrOC2O4 has porous structure with minimal grain size 30 nm. It was determined the specific surface and particle size of ZrO2 samples by the desiccator method of benzene steam adsorption, which are for sample, synthesized from ZrO(OH)2, and sample, synthesized from ZrOC2O4, respectively, 10,4 m2/g, 104,9 nm і 39,1 m2/g, 27,9 nm. It was made comparison of ZrO2 particles size calculated on the base of data according to different methods.
Inhibition Efficiency Hop Cones /Chygyrynets O.E., Galchenko G.Yu., Vorobyova V.I., Pylypenko T.M., Lipatov C.Yu. // Research Bulletin of NTUU "KPI". — 2012. — № 3. — P. 137–148. Fig. 2. Tabl. 6. Refs.: 11 titles.
This study aims at evaluating the inhibition efficiency of two different hop cones and analyzing their adsorption properties on the surface of steel components that actually comprise hop cones. By employing weight loss and potentiodynamic polarization methods, we compare volatile fractions of “Aromatic” and “Bitter” hop cones. We analyze the adsorption ability on the surface of steel components that comprise hop cones using quantum-chemical calculations. We show that the inhibition efficiency of both varieties under study do not significantly differ, though with quite a large difference by genotype, and provide effective corrosion protection of carbon steel at the periodic condensation. The experimental results demonstrate that the investigated izopropanol hop extract, which can effectively retard the anodic dissolution of steel.