Quantification of adamantane in organic media via infrared attenuated total reflection spectroscopy

In the present study, the quantitative determination of the diamondoid compound adamantane in organic solvents via infrared attenuated total reflection (IR-ATR) spectroscopy at unmodified waveguide surfaces was established. Limits of detection (LOD) and quantification (LOQ) of adamantane in dichloromethane, hexane and carbon tetrachloride were determined. Quantitative IR-ATR measurements additionally facilitated the determination of adamantane solubility limit in dichloromethane, hexane and carbon tetrachloride. The developed analytical strategy further enabled the successful detection and quantification of adamantane in crude oil matrices. Consequently, IR-ATR spectroscopy provides a promising strategy for on ship and in situ diamondoid analysis in harsh real world environments.     

The rotation period of comet 29P/Schwassmann-Wachmann 1 determined from the dust structures (Jets) in the coma

The results of the photometric observations of comet 29P/Schwassmann-Wachmann 1 are analyzed. The comet demonstrates substantial activity at heliocentric distances larger than 5 AU, i.e., outside the water ice sublimation zone. The CCD images of the comet were obtained in wideband R filters at the 6-meter telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences (SAO RAS) and at the 2-meter Zeiss-2000 telescope of the Peak Terskol Observatory. The processing of the images with special digital filters allowed the active structures (jets) to be distinguished in the dust coma of the comet. With the cross-correlation method, the rotation period of the cometary nucleus was determined as 12.1 ± 1.2 and 11.7 ± 1.5 days for the observations taken in December 2008, and February 2009, respectively. The probable causes of the difference in the estimates of the rotation period of the cometary nucleus obtained by different authors are discussed.     

C/2002 VQ94 (LINEAR) and 29P/Schwassmann-Wachmann 1 — CO and N2 rich comets

We investigated comets active at large heliocentric distances using observations obtained at the 6-m BTA telescope (SAO RAS, Russia). Long-slit and photometric modes of the focal reducer SCORPIO were used. Two of the comets, 29P/Schwassmann-Wachmann 1 (SW1) and C/2002 VQ94 (LINEAR) were observed to be emission rich. Detection of CO⁺ and N⁺₂ emissions in the comae of these comets is evidence that they were formed in the outer regions of the Solar System or in a pre-solar interstellar cloud in a low temperature environment with T?25 K. The ratio of N⁺₂/CO⁺ is equal to 0.011 and 0.027 for SW1 and LINEAR, respectively. Comet LINEAR is the most distant object in the Solar System (7.332 AU) for which CO⁺ and N⁺₂ are measured. The photometric maximum of the isolated CO⁺ coma in Comet LINEAR is shifted by 1.4 arcsec (7.44×¹⁰³ km) relative to the photometric maximum of the dust coma. This shift deviates from the sunward direction by 63 degrees.     

Structural Control of Gold-Ore Mineralization for the Eastern Slope of the Polar Urals (Russia) Based on Analysis of Multispectral Images of the Landsat 8 Spacecraft

Izvestiya, Atmospheric and Oceanic Physics - Territories of the eastern slope of the Polar Urals are promising for the identification of gold mineralization based on the materials of the...     

Ozone content over the Russian Federation in the first quarter of 2017

The review is based on the results of the operation of the total ozone (TO) monitoring system in the CIS countries. The system is functioning in the operational regime at the Central Aerological Observatory (CAO) and uses the data from the national network equipped with M-124 filter ozonometers being under the methodological supervision of the Main Geophysical Observatory. The quality of the entire system functioning is under operational control based on the observations obtained from neighboring countries and the OMI satellite equipment (NASA, USA). Basic TO observation data are generalized for each month of the first quarter of 2017 and for the first quarter. Data on surface ozone values in the Moscow region and Crimea are also provided.     

The Tolud Burst of Seismicity and the Earthquake of November 30, 2012 (<Emphasis Type="Italic">M</Emphasis><Subscript>C</Subscript> = 5.4, <Emphasis Type="Italic">M</Emphasis><Subscript>W</Subscript> = 4.8) that Accompanied the Start of the 2012‒2013 Tolbachik Eruption

This paper reports a study of the Tolud earthquake sequence; the sequence was a burst of shallow seismicity between November 28 and December 7, 2012; it accompanied the initial phase in the Tolbachik Fissure Eruption of 2012?2013. The largest earthquake (the Tolud earthquake of November 30, 2012, to be referred to as the Tolud Earthquake in what follows, with K_S = 11.3, M_L = 4.9, M_C = 5.4, and M_W = 4.8) is one of the five larger seismic events that have been recorded at depths shallower than 10 km beneath the entire Klyuchevskoi Volcanic Cluster in 1961?2015. It was found that the Tolud earthquake sequence was the foreshock–aftershock process of the Tolud Earthquake. This is one of the larger seismicity episodes ever to have occurred in the volcanic areas of Kamchatka. Data of the Kamchatka seismic stations were used to compute some parameters for the Tolud Earthquake and its largest (M_L = 4.3) aftershock; the parameters include the source parameters and mechanisms, and the moment magnitudes, since no information on these is available at the world seismological data centers. The focal mechanisms for the Tolud Earthquake and for its aftershock are consistent with seismic ruptures at a tension fault in the rift zone. Instrumental data were used to estimate the intensity of shaking due to the Tolud Earthquake. We discuss the sequence of events that was a signature of the time-dependent seismic and volcanic activity that took place in the Tolbachik zone in late November 2012 and terminated in the Tolud burst of seismicity. Based on the current ideas of the tectonics and magma sources for the Tolbachik volcanic zone, we discuss possible causes of these earthquakes.     

Influx of dissolved chemical substances to the Ob-Taz estuarine area

The results of calculation and analysis of a long-term spatial variability in volumes of the influx of a wide spectrum of dissolved chemical substances to the Ob-Taz estuarine area are under consideration. It is shown that physical transport of mineral nitrogen and phosphorus, silicic acid, petroleum hydrocarbons, phenols, heavy metal compounds down the rivers flowing into the Ob-Taz estuarine area dominates over the processes of their chemical-biological transformation. Therefore, a substantial amount of these compounds enters the estuarine ecosystems, which leads to a substantial transformation of the component composition of their water environment and a greater extent of its pollution. The latter predetermines a possible transition of the Ob-Taz estuarine area state from equilibrium into crisis, and in occasional years, even into critical state.