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1.
Cluster analysis is discussed in the context of its application to map various test areas in the sea. By analysing the correspondence of the identified categories to areas with specific hydrological conditions, an attempt is made to relate the types of fine structure to diverse background conditions. With two test areas mapped, a conclusion is made as to the possible application of cluster analysis to this end.Translated by Vladimir A. Puchkin. 相似文献
2.
碳水化合物的组合合成是一项新兴技术，该技术可以在短时间内合成大量用于进行生物活性筛选的寡糖及拟糖物。液相与固相合成技术可以极大地加快药物研究与开发进程。作者针对该技术在碳水化合物合成方面的研究进展情况进行讨论。 相似文献
3.
V. V. Egorova N. I. Volkova R. A. Shelepaev A. E. Izokh 《Mineralogy and Petrology》2006,88(3-4):419-441
Summary Ultramafic and mafic xenoliths in Ordovician Agardag alkaline basalt dikes from the Sangilen Plateau, southeastern Siberia,
provide samples from the upper mantle and crust beneath central Asia. Three major groups were distinguished among the xenoliths:
Group I xenoliths are spinel lherzolites, Group II xenoliths are spinel-garnet clinopyroxenites, and Group III comprises gabbroic
xenoliths with two subgroups: Group IIIa comprises garnet bearing gabbroids and Group IIIb is represented by garnet-free gabbroids.
The spinel lherzolite xenoliths represent the uppermost lithospheric mantle beneath the Sangilen Plateau and have geochemical
characteristics similar to those of primitive mantle. Spinel-garnet clinopyroxenite and gabbroic xenoliths are of igneous
origin and represent fragments of intrusive bodies crystallized at depths close to the mantle-crust boundary, as well as in
the lower and the upper crust. The gabbroic xenoliths are evidently the crystallization products of melts similar in major
and trace element composition to parental magma of the Bashkymugur gabbronorite-monzodiorite intrusion. Gabbroic xenoliths
from the Ordovician Agardag alkaline basalt dikes demonstrate the presence of intermediate magmatic chambers within the crust
beneath the Sangilen Plateau during the Early Palaeozoic. The relatively high equilibration temperatures of the mantle and
lower crust xenoliths in the Agardag alkaline basalt dikes are largely attributable to a plume occurring beneath the Sangilen
Plateau during the Ordovician. 相似文献
4.
The mineral chemistry and crystal morphology of kimberlite pyropes from the Billyakh River placer in the northeastern Siberian craton are characterised in terms of the placer history. The pyropes bear signatures of chemical weathering (dissolution), presumably in a Middle Paleozoic laterite profile, and therefore were originally hosted by Middle Paleozoic kimberlites. The broad occurrence of placer pyropes with lateritic dissolution signatures points to the presence of Middle Paleozoic diamond-bearing kimberlites in the study area. 相似文献
5.
Ocean Dynamics - An analytical solution to the problem of the Cyprus warm core Eddy generation over the bottom topography non-axisymmetric perturbations in the broad area of the Eratosthenes... 相似文献
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7.
Afanasiev V. P. Pokhilenko N. P. Egorova E. O. Lindenblot E. S. 《Doklady Earth Sciences》2019,489(2):1409-1412
Doklady Earth Sciences - Based on a study of diamond grains from placers of the northeastern Siberian Platform, it is shown that certain types of diamonds (rounded dodecahedroids, diamonds of the... 相似文献
8.
L. V. Egorova 《Geomagnetism and Aeronomy》2012,52(6):761-767
A joint analysis of variations in the ionospheric parameters at three vertical-incidence stations (Heiss Island, Dixon Island, and Sodankyla) and the solar wind plasma characteristics (i.e., the PC magnetic index characterizing the IMF geoeffective part) indicated that the PC index can be used as a predictor in order to diagnose the electron density level in the polar ionosphere. An increase in the PC level corresponds to positive and negative gradients in variations in the F region??s critical frequencies. As PC becomes larger than 1.5, the electron density increases at night in winter and, on the contrary, decreases during the day in summer and during daylight hours in winter. A delay in the ionospheric F region??s response to PC variations depends on the station latitude: this delay is no more than 1 and 2 h at the Heiss Island and Dixon Island stations and can be more than 6 h in summer and 0?C1 h in winter at Sodankyla. An increase in the PC amplitude as a rule corresponds to an anomalous increase in foEs relative to the median values at these stations with a delay of 1 h. 相似文献
9.
A. V. Stepanova V. S. Stepanov A. N. Larionov P. Ya. Azimov S. V. Egorova Yu. O. Larionova 《Petrology》2017,25(6):566-591
The Vorochistoozersky, Nizhnepopovsky, and Severo-Pezhostrovsky gabbro-anorthosite massifs have been studied in the central part of the Belomorian Province, Fennoscandian Shield. The similarity of geological setting and rock composition of these massifs suggests their affiliation to a single complex. The age of the gabbro-anorthosites was determined by U-Pb (SHRIMP II) zircon dating of gabbro-pegmatites from the Vorochistoozersky massif at 2505 ± 8 Ma. The studied massifs were overprinted by the high-pressure amphibolite facies metamorphism. Relicts of magmatic layering and primary magmatic assemblages preserved in the largest bodies. The massifs consist mainly of leucocratic gabbros but also contain rocks of the layered series varying in composition from olivinite to anorthosite. The presence of troctolites in the layered series indicates the stability of the olivine–plagioclase liquidus assemblage and, respectively, shallow depths of melt crystallization. Despite the composition differences between gabbro-anorthosites of the Belomorian and peridotite–gabbronorite intrusions Kola provinces, these simultaneously formed massifs presumably mark a single great igneous event. It also includes the gabbronorite dikes in the Vodlozero terrane of the Karelian province, the Mistassini swarm in the Superior province, and the Kaminak swarm in the Hearne Craton, Canadian Shield. The large igneous province of age ~2500 Ma reflects the oldest stage of within-plate magmatism after a consolidation of the Neoarchean crust of the Kenorland Supercontinent (Superia supercraton). 相似文献
10.
S. B. Lobach-Zhuchenko V. V. Balaganskii M. Yu. Koreshkova K. I. Lokhov Sh. K. Baltybaev L. M. Stepanyuk Yu. S. Egorova S. A. Sergeev I. N. Kapitonov O. L. Galankina E. S. Bogomolov N. G. Berezhnaya V. V. Sukach 《Doklady Earth Sciences》2017,474(2):700-705
This report presents data on the geological structure and location of the orthopyroxenite inclusion in gneissic enderbites of the Bug granulite–gneiss domain. Three stages of orthopyroxenite formation were identified on the basis of studies of the mineral composition along with the U–Pb and Lu–Hf isotope systems of zircons. 相似文献