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[en] An approach to the control of the sizes of oxide and metal nanoparticles produced in solutions is presented. It is assumed that a key point is the spontaneous formation of neutral hydroxo complexes usually containing 24 metal atoms. Their progressive development is either further self-assembly with the formation of particles of various-dimensions or functioning as heteroepitaxial nuclei in the formation of nanoparticles with a different composition
[ru]В работе излагается подход к управлению размерами наночастиц оксидов и металлов, образующихся в растворах. Предполагается, что ключевым моментом является спонтанное образование незаряженных аква-оксо-гидроксокомплексов, содержащих обычно 24 атома металла. Путем их прогрессивного развития является или дальнейшая самосборка с образованием частиц различной мерности, или функционирование как гетероэпитаксиальных зародышей при образовании наночастиц другого состава
[en] This work involve deals with experimental part, deals with methods and the ways used in the synthesis of 3- aryl phthalides startingfrom phthalal aldehydic acid and many phenoles and anisols containing electron with drawing groups such as (CO2H, COR, CHO, NO2), and some of the reactions that started with compounds prepared previously. (15 tabs., 12 figs., 47 refs.)
[en] The following problems are discussed within the framework of a project for the purpose of studying the metallurgical and chemical interaction between corium and reactor pressure vessel during a hypothetical accident: definition of corium composition, experimental methods for examining the properties of a corium (analytical methods, determination of melting point), isothermal crucible experiments (reaction behaviour of the binary mixtures steel-zircaloy, zircaloy-UO2, steel-UO2, and of the corium at high temperatures, thermodynamic analysis of experimental results), interaction between the corium and the reactor pressure vessel wall (kg-scale), experiments for producing a corium. (GSCH)
[de]Im Rahmen eines Forschungsvorhabens zur Untersuchung der metallurgischen und chemischen Wechselwirkung zwischen Kernschmelze und Reaktordruckbehaelter in einer hypothetischen Unfallsituation, werden die folgenden Probleme diskutiert: Definition charakteristischer Zusammensetzungen der Kernschmelze, experimentelle Methoden zur Untersuchung der Eigenschaften einer Kernschmelze (Analysenmethoden, Schmelzpunktbestimmung), isotherme Tiegelversuche (Reaktionsverhalten binaerer Werkstoffkombinationen Stahl-Zircaloy, Zircaloy-UO2, Stahl-UO2 und von Corium bei hohen Temperaturen, thermodynamische Analyse der Versuchsergebnisse), Wechselwirkung zwischen Kernschmelze und Druckbehaelterwand (kg-Massstab), Versuche zur Herstellung der Kernschmelze. (GSCH)
[en] The effects of key parameters, namely oxygen concentration, mixed fuel, and sampling positions, on the formation of carbon nano-onions (CNOs) and carbon nanotubes (CNTs) were investigated in oxy-fuel inverse diffusion flames. Particular focus was put on the intermediate species in connection with the synthesis of CNOs and CNTs. Three patterns of carbon nanostructures were observed: CNTs only, CNOs only, and CNTs/CNOs cogeneration. An appropriate temperature range in the synthesis of CNTs was identified to lie between 400 and 1,000 °C, whereas the temperature range for the synthesis of CNOs was higher, within 800–1,250 °C. A threshold value of oxygen concentration, 30 %, existed for onset of CNO synthesis. Gas composition analysis indicated that no carbon nanomaterial was formed at low CO and C2H2 concentration as well as low substrate temperature (lower than 400 °C). Compared with the synthesis condition of CNTs only, the C2H2 concentration was higher for the onset of CNTs/CNOs cogeneration, whereas the CO concentration was maintained at the same level. Additionally, the critical C2H2 concentration for the onset of CNOs only was found to be 0.4 %. A large quantity of CNOs was observed for C2H2 concentration greater than 0.4 % and CO concentration greater than 4 %.
[en] Information on the methods of synthesis of 4-aryl- or 4-hetaryl-substituted pyridines developed in the recent years is discussed and generalised. Examples of the practical use of 4-(het)arylpyridine derivatives are given.
[en] The paper is presented in the form of copies of overhead sheets. The contents concern definitions, an overview of Integrated biomass gasification and Fischer Tropsch (FT) systems (state-of-the-art, gas cleaning and biosyngas production, experimental demonstration and conclusions), some aspects of large-scale systems (motivation, biomass import) and an outlook
[en] Published data on the synthesis and reactivity of ketoesters and ketoacids containing the adamantane nucleus are summarized and generalized. Biological activities of these compounds are discussed. The bibliography includes 105 references.
[en] Data on the bacterial transformation of terpenoids published in the literature in the past decade are analyzed. Possible pathways for chemo-, regio- and stereoselective modifications of terpenoids are discussed. Considerable attention is given to new technological approaches to the synthesis of terpenoid derivatives suitable for the use in the perfume and food industry and promising as drugs and chiral intermediates for fine organic synthesis. The bibliography includes 246 references