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161.
The aim of this work is to assess the possibility and usefulness of accessing geothermal energy from the existing production well, Jachowka K-2. Discussions of both, a heat flow transferred between a deposit and a heat carrier and a heat flow permeated through the barrier are presented. A computational model, was designed to determine the volume of a gained geothermal heat flux with the use of a double-pipe geothermal heat exchanger with the dead centre [12]. Lastly, the article there are the results of calculations of available heat flux in the investigated well at the depth of L=3950 m are analyzed. 相似文献
162.
Tomasz Jękot 《Computational Mechanics》1993,12(5):269-276
This paper presents a numerical analysis of a nonlinear elastic impacted rod. The geometrical relations, mechanical equilibrium equations are linear, while the constitutive relations are nonlinear. Computations are based on spectral methods generalized to include nonlinear cases. A recurrent variational spectral method is introduced in which a discretization of the space and time variables of a function is treated in the same way. The iterative weak solutions are defined. The domain of a function is divided along a wave front to account for a boundary condition for stresses given by the Heaviside function and to include a jump of stresses on the wave front. Moduli of D54S aluminum alloy are used in the computations. The results indicate that nonlinear displacements and stresses are greater than corresponding linear ones. 相似文献
163.
Tomasz Czeppe Wojciech Zakulski Elbieta Bielaska 《Journal of Phase Equilibria and Diffusion》2003,24(3):249-254
A part of the Al-Mg phase diagram was studied in the range of composition between 48 and 61 at.% Al by DSC and SEM/EDS methods.
The temperature ranges of stability of the β, γ, and ɛ phases were considered. It was found that the congruent melting temperature
of the β phase was 450±1 °C. The Al content in that phase was determined to be 61±1 at.% Al at 420 °C. The upper temperature
limit of the stability of the ɛ phase was established to be 427±1 °C. The Al content changed from 54 at.% at 390 °C to 56
at.% at 420 °C. The lower temperature limit of the ɛ phase formation was not determined, as a result of a slow ɛ=β+γ reaction.
The hypothetical λ or ζ phases were not found, but it was observed that decomposition of oxides might produce extra thermal
effects. 相似文献
164.
Reactions of sulfur mustard with active components of decontaminants ORO and C9 (Polish abbreviations of organic decontaminating solutions) were studied and their products were identified by GC/AED. Quantitative determinations of individual products in the reaction mixtures allowed to evaluate the kinetic parameters of the mustard reactions. The major decontamination product was divinyl sulfide, the product of the elimination reaction. At certain proportions of mustard to the decontaminant's active component, substitution products were also formed. 相似文献
165.
Pohorecki W Horwacik T Janczyszyn J Taczanowski S Bamblevski VP Gustov SA Mirokhin IV Molokanov AG Polanski A 《Radiation protection dosimetry》2005,115(1-4):630-633
The spallation target model of an accelerator driven system (ADS), consisting of six 5 cm thick and 16 cm in diameter Pb segments, was constructed. Three sets of 17 Bi samples (1/2 inch in diameter and 1 mm thick) were placed in 3 Pb disc-shaped holders inside the target at 5, 10 and 15 cm from its front. After irradiation with 660 MeV proton beam gamma-spectra of radioisotopes produced in Bi were collected several times for each sample with the use of HPGe detectors in order to identify the radioisotopes and to determine their absolute activities. Their spatial distributions were then compared with respective values obtained in the calculations made with the use of FLUKA and/or MCNPX code. A fair agreement with the experiment has been observed. 相似文献
166.
Trace elements in fruiting bodies of ectomycorrhizal fungi growing in Scots pine (Pinus sylvestris L.) stands in Poland 总被引:2,自引:0,他引:2
The trace metal contents in fruiting bodies of ectomycorrhizal (ECM) fungi, symbiotic partners of Scots pine, were studied on three sites situated in west-central Poland. Elements were determined by atomic absorption spectrometry in 123 samples of 16 species. The study explored the differences in metal accumulation in relation to site, fungal species, age and part of the fruiting body and results were related to metal content in soil and plant material (roots and needles). Soil analysis revealed that results were obtained under environmental conditions not subject to strong anthropogenic pressure. Median metal concentrations did not differ disparately between sites, although the concentrations of each of the tested metals in the individual species varied to a large extent. Extremely high levels of Al with a large bioconcentration factor (BCF) were found in sporocarps of Thelephora terrestris. The spread between the highest and the lowest concentration (max/min) was very wide in Al, Cd and Pb and these elements may be considered to be absorbed preferentially by fruiting bodies of some species whereas Fe, Mn and Zn, with relatively low values of max/min, are normally absorbed by the majority of fungi. There was no clear relationship between caps and stipes in metal content. However, a tendency to higher metal concentration in the caps was observed. The metal content in young and older fruiting bodies of five different fungi was species dependent. In order to estimate the degree of accumulation of each element by plant and mushrooms, bioconcentration factors (BCFs) were calculated. In plant material (roots and needles), highest values of BCFs were noted for essential metals, like Zn and Mn. Lead showed a definite exclusion pattern (BCF below 1). In fruiting bodies of tested fungi, especially in Amanita muscaria, cadmium was the most intensively accumulated metal. Lead was excluded by plants but was accumulated or excluded by fungi depending on the species. The significance of mycological observation and quantification of the metal content in monitoring of the forest ecosystem is discussed. 相似文献
167.
A simplified analytical model for the static crushing of externally reinforced metal tubes is presented. The classical Alexander's solution is modified to take into account the contribution of the compound metal/ composite wall. The mean crushing force and the length of the local folding wave derived from this model are found to be in good agreement with the experimental data. 相似文献
168.
Tomasz P. Maniecki Paweł Mierczynski Waldemar Maniukiewicz Katarzyna Bawolak Danuta Gebauer Wojciech K. Jozwiak 《Catalysis Letters》2009,130(3-4):481-488
The influence of silver and gold addition on the activity and physicochemical properties of supported Cu/CrAl3O6 catalysts was the aim of this work. The reduction of CrAl3O6 support shows only one reduction stage attributed to Cr (VI) species reduction originating from previously oxidized binary oxide. Supported copper catalysts reduce in one or two stages depending on copper concentration representing the reduction of copper oxide—CuO, copper oxide chemically combined with Cr(III) oxide as copper chromite—CuCr2O4 and Cr(VI) species originating from surface chromate ions CrO4 2?. Additionally, the introduction of silver into supported copper catalysts Cu/CrAl3O6 can led to the appearance of silver chromate phase. XRD investigations of support CrAl3O6 alone, supported copper and gold and silver promoted copper supported catalysts calcined at 400, 700 and 900 °C indicated the presence of highly amorphous alumina γ-Al2O3 like structure network in which some of cationic locations of aluminum were occupied by chromium atoms and small quantities of α-Cr2O3 phase. Additionally, for copper, silver–copper, and gold–copper supported catalysts the following oxide phases were distinguished: monometallic oxides CuO, Ag2O, binary oxides CuAl2O4, Ag2CrO4, CuCr2O4 and even ternary oxide CuAlCrO4. In the case of gold promoted copper supported catalysts metallic gold phase was detected. Activity tests carried out for these catalysts show that the most active was 20 wt.% Cu/CrAl3O6 catalyst. Promotion of copper catalysts by silver improves the activity in methanol synthesis, what can be assigned to silver chromate formation. The analogical gold chromate like formation was not confirmed. 相似文献
169.
A significant difference between two closely related Bacillus spores has been discovered using optical chromatography. This difference can be harnessed for the separation of microscopic particles using opposing laser and fluid flow forces. Particles of different size, composition, and shape experience different optical and fluid forces and come to rest at unique equilibrium positions where the two forces balance. Separations in excess of 600 mum have been observed between Bacillus anthracis Sterne strain and its genetic relative, Bacillus thuringiensis. These findings open new possibilities for detection and characterization of the biological warfare agent, B. anthracis, the causative agent of anthrax, the deadly mammalian disease. The large optical separation between these species is surprising given their close genetic relationship but may be explained by differences in their shape and exosporium morphology, which may result in differences in fluid drag force. The observation of large differences due to less common variables indicates the complex nature of the force balance in optical chromatography, which may in the future be used to separate and characterize microbiological samples. In general, the discovery of such large differences between such closely related biological species suggests new possibilities for the separation and characterization of microorganisms using the full range of emerging techniques that employ radiation pressure (optical filtering, laser tweezers, optical chromatography, etc.). 相似文献
170.
Non-Hodgkin B-cell lymphomas (NHL) are a heterogeneous group of lymphoid neoplasms with complex etiopathology, rich symptomatology, and a variety of clinical courses, therefore requiring different therapeutic approaches. The hypothesis that an infectious agent may initiate chronic inflammation and facilitate B lymphocyte transformation and lymphogenesis has been raised in recent years. Viruses, like EBV, HTLV-1, HIV, HCV and parasites, like Plasmodium falciparum, have been linked to the development of lymphomas. The association of chronic Helicobacter pylori (H. pylori) infection with mucosa-associated lymphoid tissue (MALT) lymphoma, Borrelia burgdorferi with cutaneous MALT lymphoma and Chlamydophila psittaci with ocular adnexal MALT lymphoma is well documented. Recent studies have indicated that other infectious agents may also be relevant in B-cell lymphogenesis such as Coxiella burnettii, Campylobacter jejuni, Achromobacter xylosoxidans, and Escherichia coli. The aim of the present review is to provide a summary of the current literature on infectious bacterial agents associated with B-cell NHL and to discuss its role in lymphogenesis, taking into account the interaction between infectious agents, host factors, and the tumor environment. 相似文献