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Anatoliy Filonov 《Ocean Dynamics》2011,61(7):917-931
The dynamics of a semidiurnal internal tidal wave at a narrow Mexican Pacific shelf is discussed using the data of temperature
obtained by an anchored instrument and data of field surveys. The internal tide on the shelf is dominated by an inclined wave,
which propagates upward and onshore along a continental slope. Despite its reflection from the bottom and from the surface
of the ocean, they remain inclined and totally destroyed over the course of one wavelength. Due to wave reflection from the
inclined bottom, the horizontal and vertical wave number increase threefold when the wave goes into shallow waters. The wave
undergoes nonlinear transformation and overturns forming several homogeneous temperature layers up to 20 m thick. The most
intense disturbances of water layers are observed near the bottom, where the slope angle approaches its critical value. Because
of nonlinear effects, the wave carries cool deep water out to the shallow depth and causes coastal upwelling. Intense solar
warming together with vertical mixing results in a rapid rise of temperature in the 130-m water column that was observed. 相似文献
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Yakovlev I. V. Malkovets V. G. Gibsher A. A. Dymshits A. M. Kuzmin D. V. Danilovskaya V. A. Milaushkin M. V. Pokhilenko N. P. Sobolev N. V. 《Doklady Earth Sciences》2022,506(1):635-640
Doklady Earth Sciences - Novel data from mineralogical studies of the peridotite xenoliths from the Komsomol’skaya–Magnitnaya kimberlite pipe, Upper Muna field, Siberian craton, are... 相似文献
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Inna S. Lykova Nikita V. Chukanov Anatoliy I. Kazakov Viktor P. Tarasov Igor V. Pekov Vasiliy O. Yapaskurt Nadezhda A. Chervonnaya 《Physics and Chemistry of Minerals》2013,40(8):625-633
Products and kinetics of ion exchange of heterophyllosilicate minerals lomonosovite and murmanite with aqueous AgNO3 solutions under low-temperature conditions have been studied using scanning electron microscopy, electron microprobe analysis, single-crystal X-ray diffraction, infrared spectroscopy, 23Na nuclear magnetic resonance spectroscopy and dynamic calorimetry. Both minerals show strong affinity for silver in cation exchange. Simplified formulae of Ag-exchanged forms of murmanite and lomonosovite are (Ag3.0Ca0.5Na0.5) (Ti,Nb,Mn,Fe)3.7?4 (Si2O7)2O4·4(H2O,OH) and (Ag8.2Na1.2Ca0.3) (Ti,Nb,Mn,Fe)3.9?4 (Si2O7)2 (PO4)1.9O4·xH2O, respectively. The reaction of ion exchange for murmanite follows the first-order kinetic model up to ca. 70–80 % conversion. The rate of the process is described by the equation k(h?1) = 107.64±0.60 exp[?(12.2 ± 0.9)·103/RT]. The average heat release value in the temperature range 39.4–72 °C is 230 J g?1. The cation exchange is limited by processes in solid state, most probably binding of silver. 相似文献
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Peter O. Zavialov Anatoliy A. Ni Timofei V. Kudyshkin Durdibay P. Ishniyazov Irina G. Tomashevskaya Dilia Mukhamedzhanova 《Aquatic Geochemistry》2009,15(1-2):263-275
Starting from 1961, the Aral Sea, a major saline lake in Central Asia, has been continuously shrinking because of deficiency in its water budget. Accordingly, the salinity of the once brackish lake increased by a factor of magnitude. During the desiccation, the salt composition of the Aral Sea has been subject to continuous changes because of chemical precipitation accompanying the salinity buildup. This paper provides a summary of these changes based on water samples collected from the so-called Large Aral Sea during the field surveys of 2002–2007. Once fully ventilated, the lake developed anoxic conditions and H2S contamination is frequently observed in the bottom layers. However, hydrogen sulfide is a variable rather than a permanent feature of the present Aral Sea. Because of the precipitation of calcium carbonate, gypsum, and, possibly, mirabilite, which successively occurred as the salinity increased, the relative content of SO4 ? and Ca2+ ions decreased. Accordingly, compared with the pre-desiccation period before 1960, the sulfate-to-chloride mass ratio decreased by 10–30%, while the relative content of calcium decreased almost 7-fold. The depletion in calcium is more pronounced in the shallow eastern part of the lake, where salinity is much higher. However, the reduction of the sulfate-to-chloride ratio in the eastern basin is smaller than that for the western basin of the Aral Sea. Hypothetically, this could be explained through precipitation of halite already taking place in the eastern basin, but not yet in the western basin. Vertical profiles of the ionic content in the relatively deep western part of the lake reveal a decrease of calcium content and relative increase of sulfate ion content toward the bottom, which is consistent with the previously published concept that the bottom layers of the western trench contain a significant admixture of the water advected from the eastern basin. 相似文献
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Petra Bruckmann-Benke Niranjan D. Chatterjee Anatoliy M. Aksyuk 《Contributions to Mineralogy and Petrology》1988,98(1):91-96
Three Al-Cr exchange isotherms between Zn(Al, Cr)2O4 spinel and (Al, Cr)2O3 corundum crystalline solutions have been studied experimentally at 900°, 1100°, and 1300° C, at a total pressure of 25 kbar. Employing data on the equation of state of corundum (Chatterjee et al. 1982), the experimental results were evaluated thermodynamically. It was found that the thermodynamic mixing properties of Zn(Al, Cr)2O4 spinels are best described in terms of a symmetric Margules equation. The T- and P- dependence of the Margules Parameter, W G Sp , and of ΔG* of the exchange reaction, 1/2 ZnAl2O4 + 1/2 Cr2O3 = 1/2 ZnCr2O4+1/2 A12O3, are found to be ΔG *=1493?2.869·T+0.0081·P and W G Sp (J/mol)=23456+0.0386·P, with T given in K and P in bar. 相似文献