Purpose: The paper presents the results of phase composition and magnetic properties of Mo-Ni-Ti-C nanostructured powders. The aim of this research is understanding the correlation between key magnetic properties and the parameters that influence them in the nanostructured powders from Mo-Ni-Ti-C system. Design/methodology/approach: The powder samples were synthesised using modified sol-gel method. Obtained powder were subjected for composition and magnetic properties in a wide temperature range by means of Electron Paramagnetic Resonance (EPR) and magnetic susceptibility measurements. To study the phase composition X-ray diffraction were performed. The morphology of the powders were investigated by scanning electron microscopy (SEM). Findings: Different kinds of structural and magnetic phases have been found in the investigated compounds, e.g. (Mo, Ti)C, C, Ni. It was found that such different phases create different kinds of magnetic interactions, from paramagnetic, antiferromagnetic up to superparamagnetic. Significant magnetic anisotropy has been revealed for low temperatures, which lowers with temperature increase. Moreover, non-usual increasing of the magnetization as a function of temperature was observed. It suggests, that overall longrange AFM interaction may be responsible for the magnetic properties. Research limitations/implications: For the future work explanation which phases in Mo-Ni-Ti-C system are responsible for different kinds of magnetic interactions are planned. Practical implications: The composition of different kinds of phases may be controlled to tune magnetic properties of the nanostructured Mo-Ni-Ti-C systems. Originality/value: In this study, for the first time Mo-Ni-Ti-C nanostructured samples were prepared with different kinds of structural and magnetic phases, creating different kinds of magnetic interactions, from paramagnetic, antiferromagnetic up to superparamagnetic-like. The latter seems to be formed due to the presence of magnetic nanoparticles and longrange antiferromagnetic interactions dominating in the whole temperature range.
Wiele kopalń zmaga się z rosnącymi trudnościami związanymi z wysokim punktem piaskowym w swoich złożach. Efektem tego są zalegające hałdy drobnego piasku. Jest rozwiązanie tego problemu.
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Na3Ln(PO4)2 orthophosphates (Ln = La, Gd) doped with Er3+ and co-doped with Cr3+ ions were synthesized by Pechini method and characterized by electron paramagnetic resonance (EPR) and magnetic susceptibility measurements. Low temperature EPR spectra were detected and analyzed in terms of temperature dependence and the structure of the obtained materials. They show that erbium and chromium ions substitute Ln3+ and also Na+ ions or Na+ channels forming complex EPR spectra. Both kinds of ions reveal ferromagnetic type of interaction which shows some anomaly at the temperature between 10 K and 15 K. Magnetic susceptibility reveals a weak antiferromagnetic kind of interaction dominating in the whole temperature range, from 3.5 to 300 K.
Single crystals of ErVO4 were grown by the Czochralski method under ambient pressure in a nitrogen atmosphere. Obtained crystals were transparent with strong pink coloring. Electron paramagnetic resonance (EPR) spectra were recorded as a function of the applied magnetic fi eld. Temperature and angular dependences of the EPR spectra of the samples in the 3–300 K temperature range were analyzed applying both Lorentzian– –Gauss approximation for diluted medium and Dyson for dense magnetic medium. EPR-NMR program was done to fi nd local symmetry and spin Hamiltonian parameters of erbium ions.
Aktywne przywództwo kadry kierowniczej, zaangażowanie pracowników, otwartość, innowacyjność i przekonanie, że wszystkich wypadków można uniknąć - takie zasady przyjmuje się w CEMEX. W artykule opisano system zarządzania BHP w CEMEX i opracowany przez firmę własny autorski program „Przywództwo w Zakresie Bezpieczeństwa Pracy”, mający na celu zwiększenie świadomości, odpowiedzialności i zaangażowania pracowników, osób dozoru oraz najwyższego kierownictwa w prewencję przeciw wypadkom.
Przedstawiono niektóre zagadnienia obliczeń wytrzymałościowych rurociągów. W podsumowaniu stwierdzono, że dotychczas nie został rozwiązany problem oceny trwałości resztkowej elementów poddanych oddziaływaniom mechanicznym w ujęciu metodycznym. Nie określono również jednoznacznych kryteriów oceny stanu materiałów po wieloletnim okresie ich użytkowania.
EN
Presented are some problems of pipeline strength calculations. At a summary there is stated that there is up-to-date not solved methodologically the problem of assessment of residual durability for elements influenced by mechanical forces. There are not defined also unequivocal criteria of assessment of material condition after long time of use.
Opisano problemy eksploatacyjne związane z pracą zawieszeń wodooddzielacza z układem prowadnic pionowych na przykładzie rozwiązania konstrukcyjnego zastosowanego w elektrowniach Bełchatów i Opole. Opisano konstrukcję węzłów zawieszenia wodooddzielacza. Wymieniono zauważone nieprawidłowości w eksploatacji. Podano opis wykonanych badań oraz wynikające z nich wnioski.
EN
There are described operation problems with the co-operation of the suspension of the water separator with the vertical guide; as an example are used design solutions applied in the Bełchatów and Opole power stations.The suspension design of the water separator is described. Mentioned are observed cases of an incorrectness in the operation. A description of the tests worked out and arising conclusions are given.
The influence is emphasised of reliability of the fastening systems upon the life and faultless operation on the main power pipelines connecting a boiler with a turbine. Necessity is pointed out of checking the technical condition of the individual fastenings and determining the parameters responsible for the operation of the festenings. Diagrams of hystereses of a correct and a faulty fastening are presented. Advisability is underlined of conducting diagnostic work on the pipeline together with the fastening system during the whole time of operation of a power unit.