До питання про співпрацю журналів НАН України з "Центральноєвропейським журналом суспільних і гуманітарних наук"

Because of their high activity and selectivity to C5+ hydrocarbons in the Fischer–Tropsch, process, titania-supported cobalt catalysts have received great interest from industrial and academic, institutions. Here, we report on three catalyst preparation procedures, incipient wetness impregnation (IWI), deposition precipitation using urea hydrolysis (DPU) or ammonia evaporation (DPA) to prepare, Co/TiO2 catalysts with 4–24 wt.% Co. The results reveal a strong impact of the catalyst preparation, procedure on dispersion and distribution of cobalt over the titania surface. IWI led to clustered cobalt, oxide particles of ~10 nm, while for the DPA catalysts, similarly sized nanoparticles were found to be, well-distributed over the support surface. Co/TiO2 catalysts prepared by DPU showed the presence of, ~2 nm supported cobalt oxide particles beside large unsupported particles. Catalytic tests under, industrially relevant conditions show that the DPA catalysts displayed a superior activity and C5+, selectivity for the entire cobalt loading range studied

Святки в России

Підготовка до друку та післяслово С. Зозулі

Three-dimensional Transmission Electron Microscopy observations of mesopores in dealuminated zeolite Y**

Supported by NWO under grant 98037. The research of AJK has been made possible by a fellowship of the Royal Netherlands Academy of Arts and Sciences (KNAW). The authors thank J.E.M.J. Raaymakers for the nitrogen physisorption measurements, A.J.M. Mens for the XPS measurements, J.A.R. van Veen and E.J. Creyghton for physical data and useful discussions and Shell International Chemicals and Zeolyst for the samples

Base-catalyzed condensation of citral and acetone at low temperature using modified hydrotalcite catalysts

A study on the catalytic properties of properly activated hydrotalcite (HT) with special attention to the nature and amount of active sites present in this solid base catalyst has been undertaken. Only a small fraction (5%) of the available basic sites in the rehydrated calcined HT is active in liquid-phase aldol condensations. These sites exhibit high catalytic activity and are most likely localized at the edges of the HT-platelets. Besides a high activity, these modified HTs also show a high selectivity. No further condensation products other than diacetone alcohol (DAA) in the acetone self-condensation could be observed. Initial results with the citralacetone condensation show that even at 273 K this reaction is catalyzed by modified HTs with a conversion of 65% and a selectivity of 90%, when the citral concentration is not too high ( 1 wt.%). At higher citral concentrations, no reaction is observed indicating a negative order in citral concentration. © 2000 Elsevier Science B.V. All rights reserved

Hydrogen storage using physisorption - materials demands

A survey is presented of the storage capacities of a large number of different adsorbents for hydrogen at 77 K and 1 bar. Results are evaluated to examine the feasibility and perspectives of transportable and reversible storage systems based on physisorption of hydrogen on adsorbents. It is concluded that microporous adsorbents, e.g. zeolites and activated carbons, display appreciable sorption capacities. Based on their micropore volume ( ~ 1 ml/g) carbon-based sorbents display the largest adsorption, viz. 238 ml (STP)/g, at the prevailing conditions. Optimization of sor-bent and adsorption conditions is expected to lead to adsorption of ~ 560 ml (STP)/g, close to targets set for mobile applications

Sociale zekerheid in macro-perspectief

Sociale cohesie en sociaal-economische vraagstukke

Численная гидродинамическая модель атмосферной дисперсии загрязнений вокруг зданий

The computational fluid mechanics model of is atmospheric dispersion in the vicinity of buildings is developed. The validation of model against field experiment was performed. The application of model to problem of estimation of concentration near contaminated buildings located at the territory of Pridneprovsky Chemical Plant is presented

Applying prosodic speech features in mental health care: An exploratory study in a life-review intervention for depression

The present study aims to investigate the application of prosodic speech features in a psychological intervention based on lifereview. Several studies have shown that speech features can be used as indicators of depression severity, but these studies are mainly based on controlled speech recording tasks instead of natural conversations. The present exploratory study investigated speech features as indicators of depression in conversations of a therapeutic intervention. The changes in the prosodic speech features pitch, duration of pauses, and total duration of the participant's speaking time were studied over four sessions of a life-review intervention for three older participants. The ecological validity of the dynamics observed for prosodic speech features could not be established in the present study. The changes in speech features differed from what can be expected in an intervention that is effective in decreasing depression and were inconsistent with each other for each of the participants. We suggest future research to investigate changes within the intervention sessions, to relate the changes in feature values to the topical content of the speech, and to relate the speech features directly to depression scores

Three-Dimensional Transmission Electron Microscopy: A Novel Imaging and Characterization Technique with Nanometer Scale Resolution for Materials Science

Three-dimensional transmission electron microscopy (3D-TEM), effectuated by multiple imaging of a sample combined with image analysis, offers a new approach in materials science to obtain 3D information of complex solid materials. Here we report first-of-its-kind results that have been obtained with zeolite materials. Virtual cross-sections and volume rendering of the 3D reconstruction of a metal/zeolite crystal (Ag/NaY) give unequivocal information on the location of the silver particles (10-40 nm in diameter). Virtual cross-sections of the 3D reconstruction of an acid-leached mordenite show the three-dimensional mesoporous channel system (3-20 nm in diameter) with a clarity and definition not seen before

Балканська криза (1990–2005 рр.) в контексті геополітичних трансформацій

Досліджено трансформаційні процеси, на тлі яких розгорталася Балканська криза. Розглянуто зовнішньополітичний контекст Балканської кризи та показано як глобалізація, розпад Радянського Союзу, а отже, трансформація, а також інтеграція Західної Європи вплинули на розгортання подій в регіоні.In this article, there is analyzed the frameworks of the transformation processes of the Balkan Crisis. It revives international background of the Balkan Crisis and demonstrates the influence of globalization, Soviet Union disintegration, and therefore the NATO transformation, as well as Western European integration on the events in the Region