A study of mechanical properties of high manganese steels after different rolling conditions

In the paper, two grades of high-manganese steels with aluminum after a thermos - mechanical treatment were studied. Steel grades with an austenitic - ferritic structure with various contents of carbon, manganese and aluminum were selected for the studies. The main goal of the work was to define the most preferable parameters of heat treatment, rolling finish temperature and cooling rate in order to obtain the most favorable strength - ductility relation for the examined steels. The structural analysis was carried out using optical microscopy techniques. The evaluation of strength properties was carried out based on the results of static tensile test of steel sheets

Relationship between the spino-pelvic parameters and the slip grade in isthmic spondylolisthesis

Purpose of the study Analysis of changes in the spino-pelvic alignment, depending on the slip grade in patients with low and high-grade isthmic slip. Materials and methods A group of 60 patients who had lumbar spine radiograms adequate to measure the spino-pelvic parameters selected from a series of 195 cases of isthmic spondylolisthesis. We analyzed the following spino-pelvic parameters: pelvic incidence (PI), sacral slope (SS), pelvic tilt (PT), lumbosacral angle by Dubousset (LSA) and lumbar lordosis (LL). The ANOVA statistical test was used to examine whether there is a significant correlation between (1) the slip grade and the value of PI, PT, and LL, and the Pearson correlation was used to examine a correlation between (2) the size of PI and the value of other spino-pelvic parameters, (3) the value of LL and SS, (4) value of the LSA and LL, PI and PT. Results The greater the slip grade, the greater the value of PI, PT, and LL and lower LSA. Positive correlations have been found between PI and SS, PT and LL. There was also a positive correlation between LL and SS. Negative correlations were noted between LSA and LL, PI and PT. Conclusion The spino-pelvic alignment changes with the grade of isthmic spondylolisthesis, and the individual spino-pelvic parameters correlate together to form a causal chain in the development of isthmic spondylolisthesis

Study of the structure of intermetalics from Fe - Al system after the hot rolling

This paper presents the results of structure analysis of Fe - Al alloys after hot rolling deformation. Microstructure analysis were performed before and after deformation using a scanning transmission electron microscopy (STEM) technique. The detailed quantities research of the structures was conducted using scanning electron microscopy (SEM) equipped with the gun with cold field emission and the detector of electron back scattering diffraction (EBSD)

The effect of strain rate on the impact strength of the high-Mn steel

In the paper, results of impact bending tests of a high-manganese steel of Fe – 30 wt.%, Mn – 9 wt.%, Al – 0,65 wt.%, C grade are presented. The tests were carried out using a flywheel machine, suitable for dynamic stretching and impact bending tests in the range of linear velocity of the forcing element from 5 ÷ 40 m/s. The obtained test results were compared with the results of impact resistance of the studied steel determined using Charpy machine. Structural investigations were carried out using scanning transmission electron microscopy. Surfaces of fractures formed in the break point during bending tests were analyzed, and they indicate a presence of mixed transcrystalline fractures with a predominance of plastic fractures

Application of third generation synchrotron source to studies of noncrystalline materials : In-Se amorphous films

The local structure of vacuum evaporated In-Se amorphous films, containing 50, 60, and 66 at .% Se, was studied using differential anomalous X -ray scattering and extended X -ray absorption fine structure. Both intensity and absorption spectra were measured in the vicinity of the absorption K -edge of Se. The differential anomalous X -ray scattering data were converted to real space by the inverse Fourier transform yielding the differential radial distribution functions. The obtained results provide evidence for the presence of Se-In spatial correlations for In5 0 Se50 and Se-In and Se-Se correlations for In40 Se60 and In34 Se66 within the first coordination sphere

Stosunek Polaków do wprowadzenia całkowitego zakazu palenia we wszystkich miejscach publicznych

Attitude of Poles toward enforcement of complete smoking ban in all public placesWHO Framework Convention on Tobacco Control recommends enforcement of strong smoke-free policy in public places and worksites. Many countries of European Union, cities and states of the Unites States of America, Canadian provinces and other countries worldwide have been effectively enforced comprehensive ban of smoking in public places and worksites. Follow up studies show health and social benefits of the smoke-free policy. However, its effective enforcement requires public support. This paper analyzes results of the 2006 nation-wide randomized survey on attitudes toward complete ban of smoking in public places and worksites in Poland. In Poland, public support for the enforcement of smoke-free legislation (76%), even very restrictive, belongs to the highest in European Union countries. Its effective enforcement is crucial for improvement of public health in Poland since over 8,700 deaths (including almost 2,000 deaths among non-smokers) in Poland are caused by passive exposure to tobacco smok

Aneuploids in the shrub birch Betula humilis populations in Poland

Shrub birch (Betula humilis Schrk.) is endangered glacial relict growing in natural and drained fens and transitional mires. At present study we examined karyotypes of 103 individuals of B. humilis, collected in six populations from eastern and northeastern Poland. We found 60% of diploid individuals with 2n = 28. The rest of studied plants were aneuploids with 26, 27, 29, 30 and 31 chromosomes in their karyotypes. High frequencies of aneuploids in Polish populations of B. humilis could be a consequence of: (i) hybridization with congeneric species, (ii) stress resulting from range fragmentation, (iii) karyotype instability of individuals with 2n ≠ 28, or (iv) vegetative reproduction

Homomorphisms from functional equations: the Goldie equation

The theory of regular variation, in its Karamata and Bojani´c-Karamata/de Haan forms, is long established and makes essential use of the Cauchy functional equation. Both forms are subsumed within the recent theory of Beurling regular variation, developed elsewhere. Various generalizations of the Cauchy equation, including the Gołab–Schinzel functional equation (GS) and Goldie's equation (GBE) below, are prominent there. Here we unify their treatment by algebraicization: extensive use of group structures introduced by Popa and Javor in the 1960s turn all the various (known) solutions into homomorphisms, in fact identifying them 'en passant', and show that (GS) is present everywhere, even if in a thick disguise

mtDNA data reveal disparate population structures and High Arctic colonization patterns in three intertidal invertebrates with contrasting life history traits

Introduction: Post-glacial climate variation is known to have influenced the distribution of marine species in the North Atlantic. In particular, the Atlantic side of the Arctic has experienced strong fluctuations in both atmospheric and sea surface temperature, as well as seasonal ice coverage since the last glacial maximum (LGM). Here, we aim to unveil the phylogeography and historical demography of three rocky intertidal marine invertebrates showing a trans-Atlantic distribution and presently inhabiting the Arctic: Gammarus oceanicus, Littorina saxatilis and Semibalanus balanoides. Methods: We used a large amount of mitochondrial DNA barcode data, both newly-obtained and stored in public databases. We performed phylogeographic and demographic analyses on 1119 G. oceanicus, 205 L. saxatilis, and 884 S. balanoides sequences. Results: Our results show that all three of these boreal species have expanded their effective population sizes in the high Arctic Svalbard Archipelago since the LGM. Analyses investigating the origin of all these populations point to the eastern Atlantic. Discussion: Based on our results we conclude that the expansion of these boreal species to the Arctic possibly happened during an earlier warm cycle of the Holocene era, and is probably not the result of the recent ‘Atlantification’ of the Arctic. We also discuss the effects of dispersal potential on population structure as an important aspect of comparative biogeographical studies