Methane in Water and Bottom Sediments in Three Sections in the Kara and Laptev Seas

The methane content in water and bottom sediments was measured in vertical sections: Lena River Delta–continental slope (the Laptev Sea), Taimyr Peninsula–Voronin Trough, and along the Novaya Zemlya Archipelago. The methane concentrations varied from 2.5 to 70 nmol/L and from 590 to 2600 nmol/L in the water column and sediments, respectively. Most of the surface water samples showed oversaturation in methane (up to 19-fold, fourfold on average), which determined the water–atmosphere direction of methane fluxes, which amounted to 1–400 mol/km² day (52 mol/km² day on average).     

Changes in the Forms of Copper Occurrence in Surface Waters with Increasing Technogenic Load

Doklady Earth Sciences - The change in the distribution of Cu compounds by size fractions with an increase in its concentration in noncontaminated surface waters has been studied experimentally. It...     

Ferromanganese nodules from the Kara Sea: Interrelation between organic matter and ore elements

This study presents data on Fe–Mn nodules first recovered from the northeastern part of the Kara Sea. Analysis of the geochemical indicators of organic matter and major and trace element compositions of nodules showed that samples with strong Mn enrichment (Mn/Fe = 2.38, on average) are dominated by terrestrial organic matter (OM), whereas Fe-rich samples (Mn/Fe = 0.20, on average) are dominated by marine biogenic OM. The variation in the n-alkane abundances in the studied nodules is independent of the sampling sites and nodule morphology. This study was conducted for the first time in the Artic region.

     

Metal cation exchange reactions of ore minerals in Fe–Mn crusts of the Marcus Wake Rise (Pacific Ocean) in aqueous–salt solutions

It is shown that the reaction ability of metal cations of ore minerals in Fe–Mn crusts of the Marcus Wake Rise increases in the following manner: (Co²⁺ < Cu²⁺ < Ni²⁺) < (Mg²⁺ < Mn²⁺ < K⁺ ≈ Ca²⁺ ≈ Na⁺). The composition of the exchange complex of the ore minerals is constant and includes these metal cations. Ca²⁺ and Na⁺ are major contributors to the exchange capacity of the ore minerals. The capacity of the ore minerals by cations of alkali and base metals is 0.43–0.60 and 2.08–2.70 mg-equiv/g, respectively. The exchange capacity of the ore minerals by cations of base metals increases linearly with the increase in the MnO₂ content of the crust and does not depend on the geographical locations of the Marcus Wake guyots.     

System for scientific payload information support for the <Emphasis Type="Italic">Phobos-Grunt</Emphasis> project

This article describes a device called the System for Scientific Payload Information Support (SSPIS) that controls the traffic (commands, board time code, science and telemetry data) between the onboard computer system (OCS) and the scientific instrumentation (SI) of the spacecraft (SC) of the Phobos-Grunt project. The functional scheme of the device and the functions of the included modules are described. The scope of the testing of the device is considered. The software developed to perform functional testing of the hardware resources of the device is described.     

Organic Matter Transformation in the Conjugate Series of Surface Water in Northern Karelia

Water Resources - The composition of organic matter in the conjugated series of natural water (soil, bog, creek, and lake water) has been considered. The composition of aliphatic and aromatic...     

Experimental Research on the Photodegradation of the Organic Compounds of Natural Waters

The photodegradation of organo-mineral complexes in natural conditions was studied using samples of soil and swamp waters to study the effect of sunlight on the composition and properties of organic matter and metal forms dissolved in natural waters. The total contents of certain aliphatic and aromatic carboxylic acids increased in the samples after irradiation. Photodegradation of organic matter of the natural waters with the high Fe content is accompanied by the formation of colloidal particles (Fe hydroxides). The number of negatively-charged complexes of Ni, Cu, Zn, and Cd increased under insolation in swamp waters and decreased in soil waters.     

Migration of elements in podzolic soils of the Meshchera Lowlands (Vladimir Region,Russia): Laboratory experiment

The study of the mobility of elements under dynamic conditions, when the material from each of soil horizons is regarded as a separate adsorption-precipitation chromatographic column allowed us make quantitative estimates of the migration of elements using coefficients of interaction as extraction and retention coefficients. The results that were obtained during the modeling experiment made it possible to compile mobility sequences of elements in soil horizons.