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EN
A new method of preparation of nanocrystalline zinc aluminate (ZnAl2O4) powder is described in this paper. Different organic acids are used as template material and nitric acid as an oxidant. Single phase ZnAl2O4 spinel can be formed at a much lower temperature through this route which gives nanocrystalline powder with uniform particle size and morphology. The powders are characterized by thermo gravimetric analysis (TGA), X-ray diffraction analysis (XRD), Fourier transform infrared spectroscopy (FT-IR), BET surface area analysis and field emission scanning electron microscopy (FE-SEM). The average crystallite size of the single phase material was of 20 to 30 nm and the surface area was found to be 21 to 27 m2g-1.
EN
A simple low temperature synthesis route has been presented of preparing nanosized, single phased LaFeO3, La(1-x)SrxFeO3 (x = 0.3, 0.5) and La(1-x)SrxCo0.2Fe0.8O3 (x = 0.2, 0.4) for cathode applications in ITSOFC. A soft chemical method has been applied, using tartaric acid as a template material and nitric acid as an oxidizing agent. Phase pure materials were obtained at temperatures ranging from 550 °C to 700 °C. The synthesized powders were characterized by TGA, XRD, SEM and FTIR analysis. The crystallite size was 45-50 nm, with the surface area of 14-20 m2/g. Electronic conductivity of the material was found to increase upon increasing Sr concentration and the sintering temperature. High electronic conductivities of 355 S/cm and 545 S/cm were obtained at 400 °C for La0.5Sr0.5Fe2O3 and La0.6Sr0.4Co0.2Fe2O3, respectively. Activation energy decreases with the increase in Sr concentration. The values of thermal expansion coefficients (TEC) of the materials are compatible with the TEC of the ceria-gadolinium oxide CGO interlayer between cathode layer and electrolyte.
EN
Tectonism in the Himalayan fold-thrust belt had generated great earthquakes in the past and will spawn more in the future. Sequential cumulative moment release data of macroearthquakes (Mb ≥ 4.5) over the years 1964–2006 in four zones of the Himalaya was analysed by nonparametric RUD method. The Z values of RUD analysis had neither rejected nor supported the null hypothesis of randomness. However, the Hurst analysis and plot, a statistical procedure to identify clustering of low and high values in a time series, brought out a pattern for earthquake prognostication. The pattern was a negative sloping segment representing a sluggish moment release over years, followed by a positive sloping segment indicating a sudden high moment release with occurrence of medium/large size earthquake(s). In recent past, such a negative sloping has been found in Zones B (1992–2006) and D (1998–2006), indicating an impending moderate/mega earthquake event in near future.
EN
The seismotectonic characteristics of 1983–1984, 1993 and 2005 swarms in Andaman Sea are analysed. These swarms are characterised by their typical pulsating nature, oval shaped geometry and higher b values. The migration path of the swarms from north to south along the Andaman Spreading Ridge is documented. While the first two swarms are located along existing mapped rift segments, the 2005 swarm appears to have generated a new rift basin along 8°N. The analysis and supporting evidences suggest that these swarms were generated by intruding magmatic dyke along the weak zones in the crust, followed by rifting, spreading and collapse of rift walls. CMT solutions for 2005 swarm activity indicate that intrusion of magmatic dyke in the crustal weak zone is documented by earthquakes showing strike slip solution. Subsequent events with normal fault mechanism corroborate the rift formation, collapse and its spreading.
PL
Artykuł zawiera opis oryginalnej metody opracowania symulacyjnego modelu pracy zmechanizowanego systemu wydobywczego stosowanego w górnictwie indyjskim. W zaprezentowanym materiale opracowano model pozwa-lający na prawidłowy dobór parametrów procesu ładowania urobku i jego wpływu na produktywność kopalni. Przedstawiona w artykule metodyka modelowania symulacyjnego uwzględniająca stochastyczny charakter głów-nych parametrów może być z powodzeniem wykorzystana do modelowania licznych systemów mechanizacyjnych stosowanych lub projektowanych z myślą wdrożenia ich w polskim górnictwie. Przedstawiony w artykule model został zweryfikowany w praktyce poprzez zebranie danych ze 120 zmian roboczych.
EN
The article describes an unconventional method for making the simulation model of mechanised mining system operation used in Indian coal mining. There is presented the model that allows right selection of operating parameters of raw coal loading process and its influence on mine productivity. Presented in this article, the simulation method that regards stochastic character of main parameters may be used with a success in modelling a lot of mechanised mining systems used or planned to be implemented in Polish mining. The model has been validated in practice by gathering the data for 120 working shifts.
PL
W artykule przedstawiono krótki rys historyczny górnictwa miedziowego w Indiach z uwzględnieniem uwarunkowań społecznych i ekonomicznych wpływających na jego stan. Omówiono budowę geologiczną złóż miedzi oraz miejsca i sposób ich zalegania. Przedstawiono specyfikę rynku miedzi w Indiach, uwzględniając politykę przemysłową w indyj-skim sektorze miedziowym. Wskazano perspektywy rozwoju tej gałęzi przemysłu w trzecim tysiącleciu.
EN
The article outlines the history of copper mining in India with regard to social and economical conditions having an effect on its condition. Geological structure of copper beds as well as places and way of their deposition is discussed. The article presents the specific character of copper market in India taking into consideration trade policy of the Indian copper line of business .There are mentioned the development prospects of this industry for the third millenium.
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