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The results of studying geology, petrography and geochemistry of chlorite-amphibole rocks and fine-grained metagabbro in the Gabbro-10 massif have been presented. Chlorite-amphibole rocks are found as large fragments of irregular shape. They have a porphyraceous texture, a schistose structure and are enriched in magnesium and chromium (19 and 0.3 wt % respectively) concerning the metagabbro prevailing in the massif. According to the classification and variation diagrams of main elements, as well as to the diagrams of the trace-element composition normalized to primitive mantle, the chlorite-amphibole rocks are metamorphosed xenoliths of melanocratic norites of the Nyud-Poaz massif. Fine-grained metagabbros, on the other hand, occur in the form of numerous angular fragments concentrated near the lower contact of the intrusion. These massive rocks of the blastogabbroic texture are less enriched in magnesium and chromium (8 and 0.02 wt % respectively) and correspond to the composition of mesocratic gabbronorites. According to the spectra of trace elements normalized to the primitive mantle, fine-grained metagabbro, with pronounced negative Nb-Ta & Zr-Hf anomalies and positive Sr & Eu anomalies, corresponds to the rocks of the marginal zones of the NKT and Nude-Poaz massifs. However, the greatest similarity is established between these rocks and the schistose gabbroids of the marginal zone of the Gabbro-10 massif. Thus, the fragments of fine-grained metagabbro are possibly autoliths of the intrusion. Collectively, the obtained data have indicated the late intrusion of the Gabbro-10 massif following the crystallization of the Nude-Poaz rocks, and the presence of autoliths of its own marginal zone in the massif points at several magmatic impulses during its formation.

NASA's Solar Probe Plus (SPP) mission will make the first in situ measurements of the solar corona and the birthplace of the solar wind. The FIELDS instrument suite on SPP will make direct measurements of electric and magnetic fields, the properties of in situ plasma waves, electron density and temperature profiles, and interplanetary radio emissions, amongst other things. Here, we describe the scientific objectives targeted by the SPP/FIELDS instrument, the instrument design itself, and the instrument concept of operations and planned data products.

The influence of the moisture content on the CO2 emission from peat soils of palsa mires in the discontinuous permafrost area was studied in the north of Western Siberia (Nadym region). The СО2 flux was measured in Histic Cryosols of permafrost peatlands (palsas) and Fibric Histosols of surrounding bog using the closed chamber method for four years at the peak of the growing season (August). Despite a significant difference in the soil moisture (34.8 ± 13.2 and 56.2 ± 2.1% on average), no significant difference in the CO2 emission from these ecosystems was found in any of the observation years; the rates of emission averaged 199.1 ± 90.1 and 182.1 ± 85.1 mg CO2 m–2 × h–1, respectively. Experimental wetting or drying (with a twofold difference in the moisture content) of peat soils at the two sites via their transplantation to a different position showed no significant effect on the CO2 emission even three years after the beginning of the experiment. The absence of significant differences in the CO2 flux between the two different ecosystems was explained by the presence of permafrost and the influence of many multidirectional factors mitigating changes in the CO2 production by soils. An increased CO2 emission from the peat soils of bogs was possible due to the additional contribution of the methanotrophic barrier and the lateral runoff of dissolved CO2 over the permafrost table from the palsa toward the surrounding bog. The absence of response of the CO2 emission to a significant change in the soil moisture content may be indicative of a wide optimum of this characteristic for the microbiological activity of peat soils in the studied region. The obtained data suggest that, while studying CO2 fluxes in cryogenic soils of hydromorphic landscapes, it is necessary to take into account not only biogenic sources, but also other factors, often of a physical nature, affecting the balance of CO2 fluxes and CO2 emission from soils. [ABSTRACT FROM AUTHOR]

The possibility of obtaining sorbitol from potato starch via one-pot hydrolysis-hydrogenation is demonstrated using bifunctional catalysts 0.3–3 wt % Ru/Cs3HSiW12O40 (Ru/Cs-HPA). It is found that a catalyst with 1 wt % Ru is the one most effective, since it has the optimum ratio of the concentrations of Brønsted and Lewis acid sites on the support's surface and a large specific surface area. The kinetics of the reaction with 1% Ru/Cs-HPA is studied and the observed energy of activation of the hydrolysis-hydrogenation of starch to sorbitol is found to be 80 ± 8 kJ/mol. A kinetic model is proposed on the basis of experimental and published data. The model accurately describes the hydrolysis-hydrogenation of starch. The yield of sorbitol was 88 mol % (99 wt %) after 3 hours of the reaction using a catalyst with the optimum composition (1% Ru/Cs-HPA) at the optimum temperature (150°C). [ABSTRACT FROM AUTHOR]