395 research outputs found

    Primary structure of potato Kunitz-type serine proteinase inhibitor

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    The serine proteinase inhibitor (PSPI-51) isolated from potato tubers (Solanum tuberosum L,) comprises two protein species with pi 5.2 and 6.3, denoted as PSPI-21-5.2 and PSPI-21-6.3, respectively. They were separated by anion exchange chromatography on a Mono Q FPLC column. Both species tightly inhibit human leukocyte elastase, whereas their interaction with trypsin and chymotrypsin is substantially weaker. The sequences of both PSPI-21-5.2 and PSPI-21-6.3 were determined by analysis of overlapping peptides obtained from the oxidized or reduced and S-pyridylethylated proteins after digestion with trypsin or pepsin, Both species of PSPI-21 are composed of two chains, named chains A and B, which are linked by a disulfide bridge between Cys(146) and Cys(157). The other disulfide bridge is located within the A chains between Cys(48) and Cys(97). The amino acid sequences of the large A chains of the two forms, consisting of 150 amino acids residues each, differ in a single residue at position 52. The small chains B, containing 37 and 36 residues in PSPI-21-6.3 and PSPI-21-5.2, respectively, have nine different residues. The entire amino acid sequences of the two inhibitors show a high degree of homology to the other Kunitz-type proteinase inhibitors from plants

    Адміністративний статус морських портів

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    Валуєва Л. В. Адміністративний статус морських портів / Л. В. Валуєва // Актуальні проблеми політики : зб. наук. пр. / редкол. : С. В. Ківалов (голов. ред..), Л. І. Кормич (заст. голов. ред..), Ю. П. Аленін [та ін.] ; МОНмолодьспорт України ; НУ ОЮА. – Одеса : Фенікс, 2012. – Вип.. 46. – С. 309-319.This article analyzes the administrative status of the seaport and its specifi c features on which the concept of sea port in the broad and narrow sens

    Optimizing Technological Parameters of the Reduction Processes in Treating Steels in a Ladle Furnace

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    This work reports the possible development of reduction processes when treating the molten metal and slag using a ladle furnace under conditions of intensive stirring with an inert gas. The industrial data have been received, confirming the possibility of decreasing the concentration of ferrous and manganese oxides in the slag and stabilizing the contents of manganese and silicon in the metal

    Research on Operational Characteristics of Imported Rails under Conditions of East Siberian Railway

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    In world's manufacturing of railroad rails there are several thermal bonding methods: differentiated waterflow quenching, air-blast or spray quenching, rail head's hardening in polymer solution and bulk oil hardening; rails' service durability is strongly dependent on thermo-hardening methods. Until recently, all of rails, produced at Nizhniy Tagil and Kuznetsk Metallurgical Works, were subjected to bulk oil hardening. Only in 2010-2011, in the Russian Federation, differentiated air quenching of rails was started at the JSC "EVRAZ ZSMK"; and rail heads' hardening in polymer solution - at the JSC "Mechel". At the same time, exploitation of imported rails with differentiated hardening has been performed on Russian railways since 1995. Service durability of these rails in Siberia and the Far North is of considerable interest. In this paper we investigated the quality of P65-type rails, made in Japan, removed after use from curved track section of the East-Siberian railway

    Oxidation Processes in Blowing Steel With Inert Gas into the Ladle

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    This work reports the possible development of oxidative processes in a metal when treating the melt in the ladle under intensive stirring with an inert gas. The industrial data have been received, confirming the possibility of reducing the concentration of silicon and aluminum in the metal, as well as changing the slag chemical composition with the bath blowing with the inert gas through the top submerged lance

    A Technology of Wastewater Sludge Treatment

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    At many communities, industrial and agricultural enterprises, treatment and recycling of wastewater sludge is an urgent task as the sludge is poured and stored in sludge banks for many years and thus worsens the ecology and living conditions of the region. The article suggests a new technology of wastewater sludge treatment using water-soluble binder and heat treatment in microwave ovens

    Traditional Technology of Chromium-Tungsten Steels Facing, its Disadvantages and Suggestions for their Eliminations

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    To reveal the disadvantages of the traditional technology of facing with chromium-tungsten steels analysis of the given technology was completed. The analysis showed that the main disadvantages of the technology are high-temperature heating and underutilization of high-alloyed metal properties. To eliminate the disadvantages we developed the methods of facing allowing obtaining faced metal which state is close to that of the hardened one without cracks

    Extraction of Chromium from Carbon Ferrochromium Residual Wastes

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    This work reports the problem of processing residual wastes after producing carbon ferrochrome by recycling dust using a hydrometallurgical method with the purpose of extracting the basic component - chromium. The X-ray diffraction analysis results, chemical and granulometric compositions of dust from the carbon ferrochrome production are given. The method for the production of chemical-enrichment concentrate (CEC) by processing ferrous dust is described, with obtaining a middling product - sodium mono-chromate with its further reduction to chromium hydroxide, followed by autoclave leaching, and resulting in the production of chemically enriched chrome concentrate. The plant used for autoclave leaching and filtering is schematically depicted. The smelting process of metallic chromium using the ladle aluminothermic method is described

    Influence of Cooling Rate in High-Temperature Area on Hardening of Deposited High-Cutting Chrome-Tungsten Metal

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    The authors study the influence of cooling rate in high-temperature area for thermal cycle of high-cutting chrome-tungsten metal weld deposit on the processes of carbide phase merging and austenite grain growth for the purpose of providing high hardness of deposited metal (HRC 64-66)

    Manufacturing Component Parts of Mining Equipment With Application of Hardening Technologies

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    To ensure highest hardness and wear resistance the authors develop an aggregate technology of manufacturing mining equipment component parts. The aggregate technology of manufacturing faced component parts includes the following operations: plasma-jet hard-facing with high-speed steels; high-temperature tempering after the facing, ultrasonic surface strengthening treatment, additional tempering, reconstructive facing
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