In order to evaluate the feasibility of cryopreservation of Wych elm (
Huds.) seeds, we evaluated the seeds sensitivity to extreme desiccation and/or the ultra-low temperature of liquid nitrogen (LN; −196 °C). We also determined the critical water content (WC) of desiccated seeds and the high-moisture freezing limit of seeds desiccated or moistened to various WCs and frozen for 24 h or up to two years in LN. Germination tests revealed no critical WC for seeds to 0.03 g H
dry mass, g g
. Seeds tolerated freezing in LN within safe ranges of WC 0.03–0.21 g g
(nuts). Seeds desiccated to the safe WC and stored in LN for two years had similar germination as seeds stored at −3 °C for two years. Therefore, long-term cryopreservation of
seeds in gene banks is feasible.
Authors:L. Chmielarz, M. Zbroja, P. Kuśtrowski, B. Dudek, A. Rafalska-Łasocha, and R. Dziembaj
Alumina, zirconia and titania pillared montmorillonites additionally modified with silver were tested as catalysts of NO reduction
with NH3 or C2H4. Ammonia was much more effective reducer of NO than ethylene. The silver containing TiO2-pillared clay has been found to be the most active catalyst for NO reduction both with NH3 or C2H4. Oxidation of the reducing agents by oxygen limited the NO conversion in the high temperature region. The ammonia and nitric
oxide adsorption sites were studied by the temperature programmed desorption methods (TPD).
Authors:P. Kustrowski, A. Wegrzyn, L. Chmielarz, A. Bronkowska, A. Rafalska-Lasocha, and R. Dziembaj
Thermal decomposition of magnesium-aluminum hydrotalcites intercalated with four different polyoxometalate anions (V10O286−,Cr2O72−, W7O246−or Mo7O246−) was examined. The studied samples were prepared by the ion-exchange procedure starting from the parent carbonate-containing
hydrotalcite. The successful synthesis was confirmed by powder X-ray diffraction and chemical analysis. The samples decomposed
in two or three essential steps forming finally mixed metal oxides. The dichromate-containing hydrotalcite showed a thermal
reduction of Cr6+ to Cr3+ ions.
Authors:J. Surman, D. Majda, A. Rafalska-Łasocha, P. Kuśtrowski, L. Chmielarz, and R. Dziembaj
K-promoted hematite catalysts for ethylbenzene dehydrogenation were studied by thermal analysis (TG/DTG) and high-temperature
XRD. The formation of potassium ferrite (K2Fe2O4), considered to be a catalytically active phase, was observed during calcination of the Ce-promoted catalysts. A linear correlation
of the catalytic activity and the temperature of potassium ferrites formation was found.