Ecological testing of different selective numbers of meadow clover in the Smolensk region

Prospective selective material of the double-cut diploid meadow clover (Trifolium pratense L.) was tested. The aim of the research was to identify selective numbers mostly adapted to the ecological conditions of the Smolensk region. Six selective numbers were tested: №23 (Belarusian State Agricultural Academy), №28 (Kotlas Experimental Station, Arkhangelsk Region), № 38 (Falenki Breeding Station, Kirov region), GP-10-93 (Federal Agricultural Research Center of the North-East named N.V. Rudnitsky), №15-6-D and №440 (Federal Williams Research Center for Feed Production and Agroecology). Variety Nadezhny, which has been in the State Register of Selection Achievements since 2012, was the standard. The testing was carried out in 2012-2015 in plant breeding crop rotation on the sod mesopodzol light loamy soil. The weather conditions were favorable with increased temperature and optimal soil moisture. The selective number №23 from the Republic of Belarus has been chosen. On the average, over the three cycles of research it surpassed the standard Nadezhny by 8.4% in winter hardiness, by 23.7% in green mass yield, by 24.4% in hay yield, by 26.9% in seed yield. This selection number was the most adaptive to the conditions of the Smolensk region. It has been recommended for passing the state varietal testing

PBI-based composite membranes for polymer fuel cells

In the present study poly(2,2-(2,6-pyridin)-5,5-bibenzimidazole) was used for the preparation of novel MEAs for high-temperature polymer fuel cells (HT-PEMFCs). We prepared hybrid materials with two types of silica fillers in order to increase the MEA performances using this polymer. The membranes were characterized in terms of their microstructure and thermal stability. Cell operation tests and Electrochemical Impedance Spectroscopy were used for the characterization of the MEAs. A maximum power density of about 80mWcm−2 was obtained at 300mAcm−2 by using an imidazole-modified silica filler. The EIS technique showed that the fillers chiefly help to reduce the charge transfer resistance of the cathodic side. The gas transfer resistance may be neglected with respect to Rct, at least at low current densities

Od žab k ribi

This paper traces the development of "the big-fish-little-pond" effect (BFLPE), which asserts that students in high-ability classes and schools have lower academic self-concepts than their equally able counterparts in low- and mixed-ability environments. The paper begins with a description of the problem outlined in the BFLPE model and continues by examining early BFLPE research and by tracing advances in the field. Criticisms of the BFLPE are outlined and research is described that addresses these criticisms. The paper concludes by presenting suggestions for future BFLPE studies.V prispevku je predstavljen razvoj učinka "velike ribe v majhnem ribniku" (ang. Big- Fish-Little-Pond-Effect), ki ugotavlja, da imajo učenci v oddelkih na najvišjem nivoju nižjo učno samopodobo kot njihovi enako sposobni vrstniki v oddelkih na nižjih nivojih in heterogenih oddelkih. Uvodoma je v prispevku opisan izpostavljeni problem BFLPE modela, nato pa doprinosi na področju njegovega zgodnjega raziskovanja. Na osnovi raziskovalnih spoznanj je predstavljena tudi kritika BFLPE modela ter smernice oziroma predlogi za raziskovanje obravnavanega učinka v prihodnje