Structural characterization of Kalsilite

Thermally induced phase transformation of K-exchange LTA zeolite is followed in the range from room temperature to 1500 ºC. The frameworks collapse into amorphous intermediate products after heating between 600 and 650 °C. Prolonged heating of the intermediate product over 1100 °C results directly in formation a kalsilite [a= 8.1095 (4) Å, b =12.824 (4) Å, c =7.0674 (4) Å, β =115.89 °(3)]. The crystale phases of kalsilite in temperature range between 700 and 1500°C was investigated by X-ray powder analyses

Thermal analysis and kinetics of the chalcopyrite-pyrite concentrate oxidation process

The paper presents the results of experimental investigation of the chalcopyrite-pyrite concentrate oxidation in the air. Characterisation of the initial sample and oxidation products was done by ICP-AES, XRD, EDXRF methods. Phase stability diagrams were constructed for Cu-Fe-S-O system at 25, 450, 650 and 900 °C. Equilibrium composition of the charge for the optimal oxidation process was calculated. DTA-TG analysis was used for monitoring the oxidation process. Kinetic parameters in non-isothermal conditions were determined, based on Kissinger and Ozawa methods.Values of activation energies showed that all stages of the oxidation process occur in the kinetic field

Molecular characterization of dengue virus 1 from autochthonous dengue fever cases in Croatia

AbstractIn the summer of 2010, two autochthonous dengue fever cases were detected in Croatia. Here we report the retrospective detection of an additional case of dengue fever, representing the first sustained autochthonous transmission in Europe since 1928. In addition, we present the phylogenetic analyses based on two sequences from the Pelješac peninsula, southern Croatia. The sequences were identified as dengue virus genotype 1 and recovered from two out of the three Pelješac patients in whom infection occurred

Memory, post-socialism and the media: nostalgia and beyond

While research on the mediation of post-socialist memory has gained momentum in recent years, the field remains fragmented and limited to small-scale case studies, with little attempt to develop a more general reflection on the nature of the processes investigated. Engagement with the wider literature on the mediatisation of memory has been limited as well, with research typically applying established conceptual frameworks rather than using post-socialist materials to generate new theoretical insights. Given the state of the field, this article has a double aim. First, it offers a critical review of the main trends in existing research, focussing on four key issues: the fascination with nostalgic modes of remembering, the dominance of national frames of analysis, the lack of research on the mediation of personal and vernacular remembering, and the privileging of descriptive over explanatory modes of analysis. Second, the article outlines a new agenda for the field, and proposes three main research trajectories. The first pays attention to how mediated memories at local and national levels interact with transnational processes of remembering the Cold War, the second focusses on to the intersections between personal and public modes of mediated remembering, and the last moves the discussion from description to explanation, using comparative approaches to advance explanations of different modes of mediated post-socialist memories

AFCF and clinoptilolite use in reduction of Cs-137 deposition in several days' contaminated broiler chicks

The objective of this study was to investigate the binding efficiency of AFCF and clinoptilolite, mixed to the feed and administered orally using gastric tube to chronically Cs-137 alimentary contaminated broiler chicks. Seventy-five male Hybro broiler chicks, between 35 and 47 days of age were divided into five groups (15 birds per group) reared in cages (five birds in a cage) and fed a standard diet. Every day during 13 days of the experimental period all chicks received orally 1 ml CsCl water solution with activity of 13 10 Bq ml(-1) Cs-137 (gastric tube). Group I was the control group and received no binders. The experimental groups received the binders. Group 2 received 0.2 g of AFCF in the form of water solution (gastric tube); group 3 received 0.2% AFCF in the feed; group 4 received 2 g clinoptilolite in the form of water suspension (gastric tube) and group 5 received 2% clinoptilolite in the feed. Five chicks from each group were sacrificed on days 4, 10 and 13 of the experimental period. Using gamma spectrometric methods specific activity of Cs-137 was determined in the samples of breast meat, liver and gizzard. The results obtained showed that administering binders to the chronically contaminated broiler chicks significantly (p < 0.01) reduced Cs-137 transfer and deposition in breast meat, liver and gizzard. Decreasing deposition of Cs-137 in breast meat and internal organs increased with time of contamination and binders administration. With AFCF as a cesium binder, on day 13 of measuring the Cs-137 activity in breast meat was 80-83% lower than that in the control group, 89% in liver and 83-84% in gizzard. Natural clinoptilolite activity in breast meat tilolite demonstrated lower binding efficiency. On day 13 of measuring the 137 was 53-69% lower than that in the control group, 67-60% in liver and 59-71% in gizzard

Exact Time Speaking System

The paper describes a system for speaking the exact time, a VoIP solution produced by IRITEL, based on a family of domestic media gateways. System contains two media gateways for reliability reasons. Media gateway is a result of R&D effort in IRITEL. Exploitation experience and some traffic characteristics are described

A new approach to fast modify the zeolite surface: high speed disperser technique in the preparation of great SMZ amount.

New method for fast modification of mineral's surfac

Ibuprofen and diclofenac sodium adsorption onto functionalized minerals: Equilibrium, kinetic and thermodynamic studies

Cationic surfactant - octadecyldimethylbenzyl ammonium chloride (ODMBA) was used for modification of the three natural raw materials - bentonite, kaolin and zeolite. Adsorption of ODMBA by minerals occurred via ion exchange of inorganic cations on minerals with surfactant. Organomodified minerals - organobentonite (OB), organokaolin (OK) and organozeolite (OZ) were studied as adsorbents for removal of two non-steroidal anti-inflammatory drugs - ibuprofen (IBU) and diclofenac sodium (DS) at pH 7. For all systems, the pseudo-second order model showed the best correlation to kinetic experimental data. In all cases, the positive values of Delta H degrees indicated that the adsorption of both IBU and DS by organomodified minerals was endothermic in nature. Equilibrium data were better described by the Freundlich isotherm model, pointing to adsorbent heterogeneous active sites for adsorption. Under applied experimental conditions, the highest adsorption of both drugs was achieved by OB, while much lower capacities were observed for OK and OZ. Nonlinear isotherms and physicochemical characterization of organomodified minerals after drugs adsorption suggested complex mechanism consisting of hydrophobic interactions between hydrophobic part of the drugs and surfactants alkyl chains, electrostatic interactions of anionic forms of IBU and DS with the cationic "head" of ODMBA, as well as anion exchange of counterion ions from ODMBA micelle and anionic forms of both drugs. Adsorption of both IBU and DS was strongly dependent on the amount of ODMBA ions in the minerals

Surface adsorption of stearic acid by natural calcite

In order to obtain hydrophobic material, the surface of natural limestone with the high content of calcite (&gt;95%), was treated with 0.5, 1, 1.5, 2, 3 and 4% of stearic acid. Two methods were used for modification: the solution method and the dry coating. The obtained products were characterized using the thermal analysis (DT/TG), X-ray powder diffraction analysis (XRPD), scanning electron microscopy (SEM) and by the evaluation of floating test. Results of floating test showed that when the solution method was applied, the hydrophobicity arrived at above 99% when the amount of stearic acid was 1.5%, while with the dry coating the same hydrophobicity was achieved with 3% of stearic acid. From the position of the principal exothermic peak (&gt; 310 °C) at DTA curves, for calcites modified with dry coating and with the solution method, it can be concluded that with both modification processes, the same active sites exist at the calcite surface onto which stearic acid may be chemisorbed. However, the position and the intensity of the other exothermic peaks, indicate the differences in bonding of stearic acid at the calcite surface during the solution method and the dry coating