•We studied bathymetric zonation of benthos in the Central Arctic over a depth range spanning 14–5416 m.•Our analyses indicated faunal boundaries at depths of 650–950 m and 2600–3000 m, delineating ...sublittoral and bathyal fauna and bathyal and abyssal faunas, respectively.•Our original and previously published data collectively suggest uniform bathymetric patterns and overturn of benthic assemblages throughout the entire Central Arctic continental slope and abyssal plain.
While numerous regional studies of bathymetric zonation of benthic fauna globally have been done, few large-scale analyses exist, and no ocean-scale studies have focused on the Arctic Ocean to date. In the present work we, hence, examined bathymetric zonation of macro- and megabenthos over a depth range spanning from the shelf to the abyssal plain (14 – 5416 m) and regionally extending from the Fram Strait to the Beaufort Sea (as a whole hereafter called the Central Arctic). Based on 104 quantitative (box-corers and grabs) and 37 semi- quantitative (trawls) samples compiled from different studies we evaluated bathymetric zonation patterns in abundance, biomass and diversity, and also compared species composition among samples. Abundance and biomass decreased with depth from > 3000 ind. m−2 and > 40 g ww m−2 to ∼ 130 ind. m−2 and < 1 g ww m−2 corroborating previous studies. Diversity showed a parabolic pattern, peaking at ∼ 100–600 m. Cluster analysis revealed four (macrofauna) and five (megafauna) groups of benthic assemblages, including three that covered the upper and lower continental slope and the abyssal plains with relatively little overlap (named the Lower Shelf – Upper Slope 1, the Lower Slope and the Abyss). Substantial changes in benthic community composition were observed at depths 650–950 m (between the Lower Shelf – Upper Slope 1 and the Lower Slope) and 2600–3000 m (between the Lower Slope and the Abyss), so we interpreted these two depth horizons as major bathymetric boundaries. The first boundary (650–950 m) corresponds to the transition from sublittoral to bathyal fauna consistent with previous studies. The second boundary (2600–3000 m) reflects a decrease in benthic abundance, biomass and diversity within the Central Arctic abyssal plain. Bathymetric patterns and species overturn of benthos were relatively uniform throughout the entire Central Arctic continental slope and abyssal plain. For some regions of the Arctic Ocean, foremost for the area north from Greenland and Canadian Archipelago, benthic data are still unavailable and further research is needed.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
2.
Plasma Treatment of Vascular Implant Chudinov, V S; Shardakov, I N; Litvinov, V V ...
Journal of physics. Conference series,
06/2021, Volume:
1945, Issue:
1
Journal Article
Peer reviewed
Open access
Abstract
This paper examines a carbon layer on a blood vessel implant. The carbon layer is created by high energy ions bombarding an inner surface of the polyurethane implant. An analysis of the ...molecular structure of the layer was carried out, demonstrating the appearance of free radicals stabilized by aromatic clusters, as well as new carbon-carbon, oxygen-containing and nitrogen-containing groups in the inner surface of the blood vessel implant. The covalent adsorption of the protein on the carbon layer inside the implant has been proven. The antithrombogenicity of the carbon layer with a covalently bound protein on polyurethane implant of blood vessels in an experiment on rabbits has been shown.
A determination of the composition of primary cosmic rays in the energy range between 1 and 1000 PeV is an important objective in studies of processes involving the formation and propagation of ...cosmic rays. On the basis of experience gained in exploiting the SPHERE-2 balloon-based facility, a SPHERE-3 facility, which possesses a wider aperture and a better optical resolution, is developed. The current status of work on designing this facility is presented.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
A series of core experiments has made it possible to establish that for fractured samples, reservoir properties decrease sharply as their stress state (effective pressure) increases. With a further ...decrease (or complete removal) of the stress state, reservoir properties are not recovered in fractured reservoirs. These experiments have scientific and practical importance for the optimization of practices of production-well operation in the Tournesian–Famennian fractured reservoirs.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The existing ideas on the status of the Navier–Stokes equations are changed in taking into account the following facts: generally speaking, the terms of these equations neglected in the boundary ...layer equations are of the order of certain Burnett terms in the conservation equations; the Navier–Stokes equations cannot be used to describe slow nonisothermal gas flows since in this case it is necessary to take the Burnett temperature stresses into account; and in the transport relations the Burnett terms determine certain effects (for example, the mechanocaloric effect).
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Within the program “Marine Ecosystems of the Siberian Arctic,” based on materials collected during cruises 69 and 72 of the R/V
Akademik Mstislav Keldysh
, the distribution of chemical elements (As, ...Ba, Bi, Co, Cr, Cr, Cd, Co, Cu, Cr, Mn, Ni, Pb, Sc, Ti, Tl, Th, V, U, and Zn) and organic carbon in the benthic mass taxa of methane seepage fields in the Laptev Sea and outside of them was examined. For the first time, the bioaccumulation potential (BP) was quantified, taking into account, in addition to the concentrations of elements in organisms, their biomass. On the C-15 methane field, the ophiuroid population accumulates each element per square meter of seafloor up to 40 times greater than at the background station. Ophiuroids and bivalves exhibited elevated BP for Ni, As, Ba, Cu, Ti, V, Mn, and Zn compared to other elements. At the same time, the BP of ophiuroids significantly exceeds that of bivalves. It is suggested that the increased bioaccumulation of some heavy metals and metalloids is related to greater bioavailability of organic matter in the bottom sediments of methane seeps. Organic carbon revealed the highest BP, which was especially pronounced in the C-15 methane field. At the background station, taxa accumulate a significantly smaller (by a factor of 10) amount of carbon in their biomass. As a result of the detritus feeders’ activity, bottom sediments are enriched in organic carbon, which indicates an important contribution of benthic organisms to the carbon cycle in the Arctic seas.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Abstract
In the work, the spectral coefficient of the plasma-erosion torch on the glassy carbon surface was determined on the basis of the Wien violation law and the experimental determination of the ...brightness temperature. The possibility of using a micropyrometer to determine the spectral factor can be a plasma-erosion torch, with the help of which (spectral absorption coefficient) it is rather quick to determine the thermodynamic temperature of the plasma-erosion torch.
On cruise 82 voyage of the R/V
Akademik M.A. Lavrentyev
, comprehensive studies of ecosystems associated with hydrothermal vents and cold seeps in the Bering Sea were carried out. New data on the ...composition and structure of benthic communities of the Piip volcano were obtained. A new area of cold seeps has been discovered on the Chukchi slope of the Bering Sea. At present, the chemosynthesis communities of the Chukchi slope are the northernmost of their kind known in Pacific, and the Chukotka population of Calyptogena is the northernmost Recent population of pliocardiines in the World Ocean.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Special features of thermomechanical behavior and structure formation of shape memory alloy Ti – 19 at.% Zr – 14 at.% Nb for medical applications are studied under the conditions of upsetting at 600 ...– 1000°C with strain rates 0.1, 1, and 10 sec
–1
. The main parameters of the compressive stress–strain diagram are determined. Metallographic and x-ray diffraction analyses of the alloy are performed. The Vickers hardness of the specimens is measured. The alloy is shown to be well deformable under the conditions studied, and its sensitivity to the deformation rate is not high. Recommendations are developed for thermomechanical treatment of semiproducts from the Ti – Zr – Nb alloy.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The article describes the features and results of using the autonomous underwater vehicle (AUV)
MMT-3000
for research of Antarctic ecosystems and deep-sea biological resources of the South Seas. The ...methodology for working with an AUV in the extreme conditions of Antarctica and the technical solutions used to visually assess the distribution of bottom animals are discussed. The results of processing the data obtained by AUV during deep-sea missions in the Atlantic sector of the Antarctic during the expedition of the RV
Akademik Mstislav Keldysh
(cruise 79) in 2020 are presented. At the same time, the data of image analysis and trawl catch were compared. Based on the experience gained, the requirements to be implemented in the new AUV
MMT-3500
, which is designed and manufactured to effectively carry out deep-sea research in subsequent expeditions in the Southern Ocean, are determined.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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