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361.
S. I. Abou-Elela S. A. El-Shafai M. E. Fawzy M. S. Hellal O. Kamal 《International Journal of Environmental Science and Technology》2018,15(4):743-754
Water heater manufacturing represents one sector of household electrical appliance industry. It includes several batch processes which resulted in a highly polluted wastewater as shock loads. The objective of this study was to manage the shock loads wastewater with a simple and cost-effective approach prior to final discharge into municipality. To achieve this objective, two approaches were studied. The first approach was the chemical treatment of the accumulated shock loads wastewater using alum and an anionic polymer. Although this approach produced a very high-quality effluent, it was economically and technically infeasible. The second approach was a controlled release of the shock loads to the normal daily discharge in a way that guarantees the compliance of the end-off-pipe with the National Regulatory Standards. This solution required establishment of an equalization tank for normal daily flow and a holding tank for controlled release of the shock loads. Mathematical calculations were carried out to determine the most violating parameters in order to calculate the mixing ratio the of shock loads with the normal daily flow. Full engineering design of the proposed solution was carried out. This approach was implemented and proved to be simple, easy to operate, cost-effective and can be replicated in similar batch processing manufacturing plants. 相似文献
362.
Abdelmonem Eldougdoug Hamdy I. E. Hassnein Helmy S. O. Aboelnaga Abdul-Mohsen G. Nadi 《Arabian Journal of Geosciences》2018,11(21):687
The study area is located in the central part of the Eastern Desert of Egypt and is mainly covered by different varieties of Precambrian basement rocks represented mainly by younger and older granites, metadiorite, metavolcanics, and metasediments. The analysis and interpretation of airborne gamma-ray spectrometric survey data are essentially based on the computation of the three radioelements (U, Th, and K) favorability indices, estimation of uranium migration rate percentage, variation of eU with eTh and eU/eTh ratio, and the construction of the contour map of the (eU-eTh/3.5) in the different rock units. The highest percent of uranium migration- out or leaching rate is connected with the red and pink granites of Gebel Kadabora El-hamra, metadiorite, and red and pink granites of G. Umm Rakham (??20.8%, ??18.57%, and ??8.45% respectively), which indicates that they could represent a major U-source bodies in the area. It was observed that the metasediments and associated graphite-bearing schists west and northwest of G. Kadabora El-hamra reflect more precipitation than the other locations around the pluton (the uranium migration rates varies between 2.59 and 30%) which mean that the graphite may have acted as a reducing agent for uranium carried in oxidizing fluids (surface meteoric water) and resulted in its precipitation. In the light of the availability of uranium source, its mobility, and graphite-bearing metasediments, the area has a good potential for the possible occurrence of uranium mineralization. 相似文献
363.
364.
Paolo?A.?SossiEmail author Julie?Prytulak Hugh?St.?C.?O’Neill 《Contributions to Mineralogy and Petrology》2018,173(4):27
Vanadium has multiple oxidation states in silicate melts and minerals, a property that also promotes fractionation of its isotopes. As a result, vanadium isotopes vary during magmatic differentiation, and can be powerful indicators of redox processes at high temperatures if their partitioning behaviour can be determined. To quantify the partitioning and isotope fractionation factor of V between magnetite and melt, piston cylinder experiments were performed in which magnetite and a hydrous, haplogranitic melt were equilibrated at 800 °C and 0.5 GPa over a range of oxygen fugacities (\({f_{{{\text{O}}_{\text{2}}}}}\)), bracketing those of terrestrial magmas. Magnetite is isotopically light with respect to the coexisting melt, a tendency ascribed to the VI-fold V3+ and V4+ in magnetite, and a mixture of IV- and VI-fold V5+ and V4+ in the melt. The magnitude of the fractionation factor systematically increases with increasing log\({f_{{{\text{O}}_{\text{2}}}}}\) relative to the Fayalite–Magnetite–Quartz buffer (FMQ), from ?51Vmag-gl = ? 0.63?±?0.09‰ at FMQ ? 1 to ? 0.92?±?0.11‰ (SD) at ≈?FMQ?+?5, reflecting constant V3+/V4+ in magnetite but increasing V5+/V4+ in the melt with increasing log\({f_{{{\text{O}}_{\text{2}}}}}\). These first mineral-melt measurements of V isotope fractionation factors underline the importance of both oxidation state and co-ordination environment in controlling isotopic fractionation. The fractionation factors determined experimentally are in excellent agreement with those needed to explain natural isotope variations in magmatic suites. Furthermore, these experiments provide a useful framework in which to interpret vanadium isotope variations in natural rocks and magnetites, and may be used as a potential fingerprint the redox state of the magma from which they crystallise. 相似文献
365.
S.?Yu.?SokolovEmail author A.?O.?Mazarovich N.?N.?Turko K.?O.?Dobrolyubova A.?S.?Abramova Yu.?A.?Zaraiskaya E.?A.?Moroz 《Geotectonics》2018,52(4):401-420
Manifestations of fluids and deformations in the sedimentary cover, which are both factors of brightening (blanking anomalies) in seismoacoustic records, in the equatorial segment of the Atlantic coincide with the sublatitudinal zones of the activated passive parts of transform faults and with zones of lower gravity anomalies and higher values of remnant magnetization, which form as a result of serpentinization. The cause-and-effect sequence of intraplate phenomena includes: the contrasting geodynamic state → horizontal movements that form macrofractures → water supply to the upper mantle → serpentinization of rocks in the upper mantle → deformations associated with vertical uplift of basement and sedimentary cover blocks, coupled with fluid generation → and fluid accumulation in the sedimentary cover, accompanied by the formation of anomalies in seismoacoustic records. Based on the seismic data, we have identified imbricate-thrust deformations, diapir structures, stamp folds, and positive and negative flower structures, indicating the presence of strike-slip faults in the passive parts of transform faults. The general spatial distribution of deformation structures shows their concentration in cold mantle zones. Correlative comparison of the structural characteristics of deformations shows the direct relationship between the heights of structures and the development of serpentinization processes. As per the age of the basement, deformations range from 27–38 to 43–53 Ma; a quite thick sedimentary cover makes it possible to reveal them based on the characteristic types of seismoacoustic records. The formation of the Antilles arc ca. 10 Ma ago affected the equatorial segment of the Atlantic; it formed kink bands where lithospheric blocks underwent displacements with counterclockwise rotations, deformations related to compression and vertical uplift of crustal fragments, and local extension that favored degassing of endogenous fluids. Sublatitudinally oriented imbricate-thrust deformations with different vergences indicate irregularity and alternating strike-slip directions as blocks between fractures were laterally influenced. 相似文献
366.
O. G. Epshtein 《Lithology and Mineral Resources》2018,53(5):404-416
Common basal moraines display diverse glaciodynamic structures inherited from the parental moraine-containing ice. Since these glacial diamictons are marked by instable structure and composition, they can resemble sediments of another origin and their identification is a difficult task. We cannot make substantiated genetic conclusions based on certain lithological properties typical of glacial diamictons. Only a set of specific features can provide sufficiently reliable determination of their glacial nature. Other methodical approaches applied in different regions, the Barents Sea included, for the identification of glacial diamictons based on the highly superficial analysis of some (usually secondary) features lead to a biased genetic interpretation of moraines. 相似文献
367.
Electron microprobe data on phosphide grains detected for the first time in basalts from volcanic edifices in the Sea of Japan are presented. The find of phosphides can testify to the endogenic source of phosphorus and, consequently, volcanogenic hydrothermal origin of phosphorites in the Sea of Japan. 相似文献
368.
Al. V. Tevelev I. A. Prudnikov Ark. V. Tevelev A. O. Khotylev E. A. Volodina 《Moscow University Geology Bulletin》2018,73(3):238-246
The structural features and mechanism of the formation of the Sim trough within the Uralian Foredeep, as well as the development of the entire Karatau–Suleiman block, are considered. This wedge-shaped block was subject to lateral extrusion to the north along conjugated strike-slip fault zones under a general latitudinal compression. This factor determined the local meridional compression and latitudinal extension of the block. In the central part of the block, the latitudinal extension was compensated by gradual subsidence, which resulted in the formation of the Sim trough. 相似文献
369.
O. M. Makarova N. I. Korobova A. G. Kalmykov G. A. Kalmykov 《Moscow University Geology Bulletin》2018,73(2):213-217
The section structure was characterized according to the lithological and petrophysical studies of the core from the Bazhenov Formation that has been uncovered in the central part of the Tundrin Depression. The productive oil intervals where the reservoirs of the pore and fissure-pore types occur were identified. 相似文献
370.
N. A. Nekrylov D. V. Popov P. Yu. Plechov V. D. Shcherbakov L. V. Danyushevsky O. V. Dirksen 《Petrology》2018,26(4):329-350
Late Quaternary volcanoes of Sredinny Range (Kamchatka) attract geoscientists’ attention by their unusual geochemical features and geodynamic setting. They produced volcanic rocks that are enriched relative to N-MORB in most of incompatible trace elements (except HREE), including strong enrichment in large-ion lithophile elements, and show a negative Nb–Ta anomaly, which is typical for rocks formed in supra-subduction settings. However, modern subduction of the Pacific Plate does not reach the most part of Sredinny Range, as inferred by mapping of Wadati–Benioff zone or seismic tomography. We constrain the source of parental magmas for Sredinny Range volcanic rocks by combining major and trace element geochemical data for olivine and naturally quenched olivine-hosed melt inclusions for Holocene tephra layers of the Kekuknaisky field. Composition of the most magnesian olivine (Ni > 2000 ppm, Fe/Mn ≈ 75 at Mg# ~ 84–85 mol %) and geochemical characteristics of the most primitive melts (FC3MS = 0.61 ± 0.04 (2s)) are consistent with their derivation from a pyroxenite source, while elevated LREE/HREE ratios in lavas indicate that it contained garnet. This garnet-bearing pyroxenite likely originated from the lower crust or lithospheric mantle. Its melting could have occurred due to delamination and sinking into the hotter mantle. 相似文献