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461.
462.
Bogusław Woźniakowski 《International Journal of Mineral Processing》1976,3(3):281-284
Based on the results of large-scale industrial experiments, the value of utilizing flotation tailings for the production of cellular concrete is discussed. The paper is confined to the technical and ecological aspects of the process. 相似文献
463.
David Gubbins Emile A. Okal Roberto Scarpa R. E. Anderson Leszek Czechowski Rodney W. Page Bernhard Spörli Magdalena Kądziałko-Hofmokl J. A. Majorowicz Gregory Houseman Donald L. Turcotte David F. McTigue Teng-fong Wong David Lockner David V. Wiltschko David M. Fountain G. P. Glasby R. J. Angel S. J. Gibowicz Jonathan Franzen Kacper R. Rybicki Brian Farrell Anil Suri Zbigniew W. Kundzewicz Witold G. Strupczewski 《Pure and Applied Geophysics》1988,127(4):695-752
464.
A. Ziółkowska M. Margas H. Grajek J. Wasilewski B. Adomas D. Michalczyk A. I. Piotrowicz-Cieślak 《International Journal of Environmental Science and Technology》2016,13(5):1335-1346
The objective of this study was to propose a method for efficient degradation of tetracycline as a water contaminant. UV-C rays, ozonation, and iron chelates were used for removal of tetracycline from water. Aqueous solution of tetracycline (5 × 10?5 M) was exposed to UV-C rays (in two doses—6 and 12 W), ozonation (at 6–12 mg ozone), or iron chelates: iron(III) sodium ethylenediaminetetraacetate, iron(III) trisglycinate, and iron(III) citrate. For each of iron compounds, three doses were studied: 2.5 × 10?5 M, 5 × 10?5 M, 10 × 10?5 M. The experiments have shown that aqueous solution of tetracycline (5 × 10?5 M) is immediately degraded as a result of ozonation with 12 mg ozone. Absorbance of tetracycline decreased from A = 0.78 to A = 0.35 after 20-min ozone treatment of sample. The fluorescence spectra revealed the presence of two ozone-induced TC degradation products with fluorescence maxima at 523 and 531 nm appearing immediately after the ozonation treatment. On the other hand, iron(III) sodium ethylenediaminetetraacetate and iron(III) trisglycinate gave rise to a single TC degradation product with a fluorescence maximum at 531 nm, observed after 10 days of the experiment. On application of iron(III) trisglycinate, at any studied concentration, tetracycline becomes degraded faster—in 4 days. Iron(III) citrate degraded 90 % of tetracycline, when used at the level 10 × 10?5 M. The biggest changes in tetracycline concentration were obtained as a result of ozonation and iron(III) citrate treatments. 相似文献
465.
O. S. Shtyka M. M. Błaszczyk J. P. Sęk 《International Journal of Environmental Science and Technology》2016,13(10):2401-2414
The stabilized emulsions removal from the aqueous systems is supposed to be an issue as important as the free oil products recovery. This work was conducted to investigate the mechanisms of oil-in-water emulsions sorption in a non-woven oleophilic/hydrophobic material forced by the capillary suction pressure, and the saturation level of such material during this process. It ensures the effective application of the sorbents and facilitates the development of alternative high-performance sorptive materials that can contribute to diminishing of the negative consequences of the aquatic environment contamination. The main aspect investigated in this research work was kinetics of the imbibition process in the porous media to define the optimal time of sorption and the height of the emulsions penetration. The measurement of the dispersed phase concentration changes with the increase in an emulsion front in the porous medium using the nephelometrical method is the advanced approach in the field of assessment of sorbents efficiency. The tendency of the imbibed emulsion concentration decrease versus the height was observed, which depended strongly on the viscosity and the initial composition of a penetrating liquid. The observed process was described by the mathematical model based on Hill equation. 相似文献
466.
M. Zielińska K. Bułkowska A. Cydzik-Kwiatkowska K. Bernat I. Wojnowska-Baryła 《International Journal of Environmental Science and Technology》2016,13(9):2239-2248
Bisphenol A (BPA) is an endocrine disruptor that is difficult to completely remove from wastewater by conventional biological methods. Increased post-treatment BPA removal with ceramic membranes is worth investigating because of these membranes’ mechanical and chemical stability and lifespan. To determine the effectiveness of ceramic membranes for post-treatment of biologically treated BPA-contaminated wastewater, microfiltration (MF) and nanofiltration (NF) were conducted. Both processes removed BPA completely at an initial BPA concentration of 0.3 ± 0.14 mg/L. Increased concentration of 0.7 ± 0.29 mg/L decreased BPA removal. MF removed at least 24 % of BPA, presumably because BPA was adsorbed on particulate matter, which was retained by the membrane, or adsorbed on its surface. NF removed up to thrice more BPA. MF and NF completely removed suspended solids and 40–60 % COD. Filtration capacity decreased with time due to fouling but did not depend on initial BPA concentration. BPA concentrations in municipal wastewater are typically lower than the lowest concentration tested, where MF completely removed BPA. Hence, MF ceramic membranes appear a promising solution for post-treatment of BPA-containing wastewater. MF can be used at a much lower transmembrane pressure than NF, requiring less energy to pump wastewater through the membrane, thus reducing costs. 相似文献
467.
468.
469.
E. Słaby L. Galbarczyk-Gąsiorowska R. Seltmann A. Müller 《Mineralogy and Petrology》2007,89(1-2):1-29
Summary Alkali feldspar megacrysts from the porphyritic Karkonosze granite (Western Sudetes, Poland) were formed during magma mixing.
Barium concentrations in zoned crystals, a sensitive indicator of feldspar migration between coeval magmas, serve to reconstruct
the crystallization path of the megacrysts. Based on geochemical data, a double mixing model for the formation of the porphyritic
granite and for megacryst growth is constructed. The feldspar growth model supports megacryst nucleation and early crystallization
in a hybridized crustal magma of granodioritic composition. The growth model gives credibility of the choice of partition
coefficients used in the modelling. Insights gained from mixing models based on whole rock composition and mineral zonation
allow the recognition of various hybridization events that are reflected in a variety of megacryst crystallization paths within
the pluton. 相似文献
470.
Genrietta A. Pospelova Elżbieta Król Galina M. Levkovskaya Jadwiga Kruczyk Magdalena Kądziałko-Hofmokl Sergey A. Kulakov 《Acta Geophysica》2007,55(4):619-639
The paper presents the results of experimental rock-magnetic, paleomagnetic and palynologic study of Paleolithic sediments
sampled along two profiles in the Akhshtyrskaya cave, situated in the vicinity of Black Sea shore. In the upper part of profiles,
some magnetite was observed; in the middle and lower parts, strongly oxidized non-stoichiometric magnetite and hematite prevail.
Thin maghemite covers on the surface of fine magnetite grains are present in the majority of specimens. Natural remanence
has one characteristic component (CHRM), mostly of chemical origin, although in few specimens containing magnetite it may
be sedimentary. Directions of CHRM obtained by standard paleomagnetic methods revealed anomalous pattern only in layer 3/2,
which is slightly older than the overlying layer 3/1 whose age was established as (35±2)×103 years BP by the U-Th method. This suggests that this paleomagnetic anomaly (PMA) can be correlated with Kargapolovo excursion
dated on about (45−39)×103 years BP. In the remaining overlying and underlying layers, directions of CHRM are grouped around the present geomagnetic
field. Depth distributions of scalar magnetic parameters generally coincide with the lithological division of the profiles.
Palynologic study revealed the presence of 22 pollen zones. Five thermomers separated with colder periods were found in the
middle and lower parts of profile. The non-magnetite composition of magnetic fraction of the majority of studied sediments
— oxidized nonstoichiometric magnetite and hematite — resulted in the lack of correlations between paleoclimatic and scalar
magnetic characteristics. 相似文献