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This work investigated two titanium-based alloys with a constant tantalum content and variable contents of alloy additives – niobium and zirconium. The Ti-30Ta-10Zr-20Nb (wt.%) and Ti-30Ta-20Zr-10Nb (wt.%) alloys were obtained using a combination of powder metallurgy and arc melting methods. The influence of alloying additives on the structure and properties of the Ti-Ta-Nb-Zr system was studied using, among others: X-ray diffraction and scanning electron microscopy. The X-ray diffraction confirmed the single-β-phase structure of both alloys. In addition, the microscopic analysis revealed that a higher amount of zirconium favoured the formation of larger grains. However, the microhardness analysis indicated that the alloy with the higher niobium content had the higher microhardness. Importantly, the in vitro corrosion study revealed that the addition of niobium promoted the better corrosion resistance of the investigated alloy. [ABSTRACT FROM AUTHOR]

The aim of this work was to investigate the microstructure and mechanical properties of the two-component melt-spun (TCMS) alloy produced from Ni40Fe40B20 and Ni70Cu10P20 melts. The Ni40Fe40B20, Ni70Cu10P20, Ni55Fe20Cu5P10B10 alloys were arc-melted. Then the alloys were melt-spun in the two different ways i.e.: by casting from a single-chamber crucible and from the two-chamber crucible. All of the above mentioned alloys were processed in the first way and the Ni40Fe40B20 and Ni70Cu10P20 were simultaneously cast on the copper roller from the two-chamber crucible. The microstructure of the alloy was studied using transmission electron microscopy (TEM), scanning electron microscopy (SEM) with energy dispersive spectrometry (EDS) and light microscopy. The mechanical properties were investigated using tensile testing and nanoindentation. The two-component melt-spun (TCMS) amorphous Ni55Fe20Cu5P10B10 alloy present hardness, tensile strength and Young modulus on the significantly higher level than for a single phase amorphous Ni55Fe20Cu5P10B10 alloy and slightly below the corresponding values for the Ni40Fe40B20.

Jakub Kortas,1 Katarzyna Prusik,2 Damian Flis,3 Krzysztof Prusik,1 Ewa Ziemann,4 Neil Leaver,5 Jedrzej Antosiewicz6 1Department of Recreation and Tourism, Gdansk University of Physical Education and Sport, Gdansk, Poland; 2Department of Biomedical Basis of Health, Gdansk University of Physical Education and Sport, Gdansk, Poland; 3Department of Bioenergetics and Physiology of Exercise, Medical University of Gdansk, Gdansk, Poland; 4Department of Physiology and Pharmacology, Gdansk University of Physical Education and Sport, Gdansk, Poland; 5The Immunosuppression monitoring service (IMS) Laboratory, Royal Brompton & Harefield NHS Foundation Trust, Heart Science Centre, Harefield Hospital, Harefield, UK; 6Department of Biochemistry, Gdansk University of Physical Education and Sport, Gdansk, Poland Background: Despite several, well-documented pro-healthy effects of regular physical training, its influence on body iron stores in elderly people remains unknown. At the same time, body iron accumulation is associated with high risk of different morbidities.Purpose: We hypothesized that Nordic Walking training would result in pro-healthy changes in an elderly group of subjects by reducing body iron stores via shifts in iron metabolism-regulating proteins.Methods: Thirty-seven women aged 67.7±5.3 years participated in this study. They underwent 32 weeks of training, 1-hour sessions three times a week, between October 2012 and May 2013. Fitness level, blood morphology, CRP, vitamin D, ferritin, hepcidin, and soluble Hjv were assessed before and after the training.Results: The training program caused a significant decrease in ferritin, which serves as a good marker of body iron stores. Simultaneously, the physical cardiorespiratory fitness had improved. Furthermore, blood hepcidin was positively correlated with the ferritin concentration after the training. The concentration of blood CRP dropped, but the change was nonsignificant. The applied training resulted in a blood Hjv increase, which was inversely correlated with the vitamin D concentration.Conclusion: Overall the Nordic Walking training applied in elderly people significantly reduced blood ferritin concentration, which explains the observed decrease in body iron stores. Keywords: ferritin, hemojuvelin, hepcidin, vitamin D, anti-agingA Letter to the Editor has been recieved and published for this article.

The article contains methodical approaches in the process of conducting practical classes with the students on discipline «Physical recreation». The methodical reception is shown, also their definition, the importance of definitions during the life of the person, including the student. The essence of physical recreation in the understanding of students for passive and active recreation is uncover, as well as formulating the tasks in forming, recovering, strengthening and preserving the health of different age groups of the population. The methodological principles of physical recreation described in detail in the context of its performance by students. It uses traditional principal means for physical culture ((physical exercise, movement modes, natural factors, massage, occupational therapy, mechanotherapy). They are distinguished by various forms, methods, and activities, bearing recreational character.

Scientists and medics are still searching for new metallic materials that can be used in medicine, e.g., as material for implants. The following article proposes materials based on titanium with vital elements prepared by combined powder metallurgy and arc melting methods. Four compositions of Ti-28Ta-9Nb, Ti-28Ta-19Nb, Ti-28Ta-9Zr and Ti-28Ta-19Zr (wt.%) have been prepared. The tested material was thoroughly analyzed by X-ray diffraction and scanning electron microscopy. Qualitative phase analysis using X-ray diffraction showed the presence of two phases, a' and ß titanium. In addition, a microhardness test was conducted, and the material was characterized in terms of corrosion properties. It was found that the corrosion resistance decreases with an increase of the ß phase presence. [ABSTRACT FROM AUTHOR]

In the presented work, two multicomponent Cr25Zr25Co20Mo15Si10Y5 and Cr25Co25Zr20Mo15Si10Y5 alloys were produced from bulk chemical elements using the vacuum arc melting technique. X-ray diffraction phase analysis was used to determine the phase composition of the obtained materials. Microstructure analysis included scanning electron microscopy and energy dispersive X-ray spectroscopy techniques. The studies revealed the presence of multi-phase structures in both alloys. Elemental distribution maps confirmed the presence of all six alloying elements in the microstructure. The segregation of chemical elements was also observed. Microhardness measurement revealed that both alloys exhibited microhardness from 832(27) to 933(22) HV1. [ABSTRACT FROM AUTHOR]

This work investigated two titanium-based alloys with a constant tantalum content and variable contents of alloy additives - niobium and zirconium. The Ti-30Ta-10Zr-20Nb (wt.%) and Ti-30Ta-20Zr-10Nb (wt.%) alloys were obtained using a combination of powder metallurgy and arc melting methods. The influence of alloying additives on the structure and properties of the Ti-Ta-Nb-Zr system was studied using, among others: X-ray diffraction and scanning electron microscopy. The X-ray diffraction confirmed the single-ß-phase structure of both alloys. In addition, the microscopic analysis revealed that a higher amount of zirconium favoured the formation of larger grains. However, the microhardness analysis indicated that the alloy with the higher niobium content had the higher microhardness. Importantly, the in vitro corrosion study revealed that the addition of niobium promoted the better corrosion resistance of the investigated alloy. [ABSTRACT FROM AUTHOR]

The aim of the presented study is to examine the influence of systematic nordic walking training on the subjective quality of seniors' lives. The control group consisted of people who do not take part in any physical activity. In order to reveal the connections between quality of life and participation in nordic walking the examination consisting of three psychological tests was performed. These were the tests measuring the level of satisfaction with life (SWLS), the level of optimism (LOT-R) and the Beck Depression Inventory level. The results of the studies have confirmed the hypothesis that the quality of life in a group of seniors in the experimental group is higher than in the control group. Statistical tests have shown that active seniors feel greater satisfaction from their lives and look in the future more optimistic than their peers in the control group containing inactive seniors. In the experimental group were lower results in scale measuring level of depression. Low results show that systematic training is unconductive to depression development.

The comparison between NiFe2O4 (co-precipitation) and NiFe2O4@SiO2 (co-precipitation and microemulsion) ferrite nanoparticles in their as-received and annealed form is presented. The structural characterization revealed the gradual crystallization of as-received samples induced by thermal treatment. The existence of cubic inverse spinel ferrite structure with tetrahedral and octahedral iron occupancy is confirmed in all samples by the comprehensive study. The Fourier-transform infrared (FTIR) spectroscopy confirmed the typical spinel structure and other Fe-based states, whereas the presence of nonstoichiometric hematite is detected in the annealed NiFe2O4 sample. In the case of nanoparticles embedded into the silica matrix, the crystallization of initially amorphous silica is revealed in structural and microstructural characterization. As shown by FTIR, the applied thermal treatment reduces the water molecules and hydroxyl units compared to the initial material. The separation of the rhombohedral hematite α-Fe2O3 phase in the NiFe2O4 ferrite evidenced during the annealing process is demonstrated in structural and magnetic studies. The analysis of saturation magnetization pointed to the spin canting phenomenon in the surface layer with a slight change of the so-called dead layer upon heating. The room temperature superparamagnetic state (SPM) is modified in the NiFe2O4 sample across annealing as an effect of ferrite crystallization and grain growth as well as hematite separation. For as-received NiFe2O4, with temperature decrease, the blocking process preceded by the freezing process is observed. The silica shell is recognized as the sustaining cover for the SPM state. The electronic structure studies confirmed the complex nature of the Fe-based states. [ABSTRACT FROM AUTHOR]

Byline: G. Dercz, K. Prusik, B. Formanek, L. Pajak The studied composite powder of high corrosion resistance was prepared using the Self-propagating High-temperature Synthesis (SHS) process. The as-prepared material was crushed and was subjected to a milling process by high-energy attritory mill for two and ten hours. The powder morphology was analysed through the Scanning Electron Microscopy (SEM) method. The structure investigations were performed using the SEM and XRD methods. The presence of Cr7C3, FeCr and FeO phases, besides the most desired FeAl(Cr), Cr3C2 and TiC ones, was noted. It was found that the FeAl(Cr) phase is of the ordered B2-type structure and the ordering degree diminishes with the increase of milling time. The crystallite size of this phase, both in the as-prepared state and after the milling process, is in the nanoscale. The crystallite size of the FeO phase diminishes to 75 nm in the sample ground for 10 h, whereas those of the other phases are above 100 nm for the as-prepared and ground samples.

In this paper, the influence of Mo addition on the structure and mechanical properties of the NiCoMnIn alloys have been studied. Series of polycrystalline NiCoMnIn alloys containing from 0 to 5 mas.% of Mo were produced by the arc melting technique. For the alloys containing Mo, two-phase microstructure was observed. Mo-rich precipitates were distributed randomly in the matrix. The relative volume fraction of the precipitates depends on the Mo content. The numbers of the Mo rich precipitates increases with the Mo contents. The structures of the phases were determined by the TEM. The mechanical properties of the alloys are strongly affected by Mo addition contents. Brittleness of the alloys increases with the Mo contents. [ABSTRACT FROM AUTHOR]

An equiatomic multi-component alloy Ni20Ti20Ta20Co20Cu20 (at. %) was obtained using vacuum arc melting. In order to characterize such an alloy, microstructure analysis has been performed using Scanning and Transmission Electron Microscopy, Electron Backscattered Diffraction, X-ray Diffraction and Energy Dispersive X-ray Spectroscopy techniques. Microstructure analysis revealed the presence of one rhombohedral and two cubic phases. Energy Dispersive X-ray Spectroscopy measurements revealed that both observed phases include five chemical elements in the structure. Using Rietveld refinement approach the lattice parameters were refined for the observed phases. [ABSTRACT FROM AUTHOR]