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According to the forecast of IPCC (Intergovernmental Panel of the Climate Change), an increase in precipitation is expected in this century in the Arctic. The main reason is intensification of evaporation from waters of the Arctic Ocean opening due to the intensive melting of sea ice. It is supposed that these changes will be most severe in winters in the Arctic regions, which are subject to significant anthropogenic load. In this respect, the intensively developed Nadym Lowland may be considered as a promising area for researches. The results of our study showed that the circulation conditions (primarily cyclones coming from the North Atlantic under the Eastern (E) circulation form of the G.Ya. Vangenheim–A.A. Girs classification) significantly influence on the isotopic composition of precipitation in this region. Thus, in the cold period of 2016–2017, the isotopic composition of precipitation changed for δ18О by 21 ‰, and for δD by 167 ‰ (weighted average values δ18О = −22.3 ‰, δD = −172.6 ‰, and dexc = 5.6 ‰). The use of the dew point temperature at the moment of precipitation in the calculations of the isotopic-temperature dependences allows obtaining the following coupling equation: δ18О = 0.67Tdp − 15.2 (R2 = 0.67). On the basis of the joint analysis of synoptic, trajectory and isotopic data, the main regions-sources of atmospheric moisture, precipitated in the Nadym Lowland during the cold period of 2016–2017, were determined. The major contributions were made by the Atlantic Ocean (35.7%), the North Atlantic Ocean and the Arctic Ocean (30.4%), and the Black Sea-Caspian region (20%). The last one is characterized by the most weighted isotopic composition. Inland source regions have contributed the least to precipitation (slightly larger 10%), and their lightweight isotopic composition is related to cryogenic fractionation.

On the basis of about 430 analyses, the 18 O and D compositions (%o) of atmospheric precipitation, ground ice, surface and inter-permafrost underground waters of cryogenic-aeolian landscapes of Central Yakutia (Eastern Siberia) are discussed. Precipitation compositions here demonstrate a large annual variation (from -6.12 to -45.0 % for δ 18 O, and from -72.1 to -350.1 % for δ D), and they are described by the Local Meteoric Water Line according to the equation δD = 7.815 18 O - 1.57). In winter and in the process of spring melting, the snow storage is subjected to a significant evaporative fractionation, that is expressed by the equation δD = 6.855 18 O - 31.9. The heaviest and deuterium-depleted compositions (δ 18 O = -19.3 %, δD = -160.9, d exc = -6.7 %) are found in the last snow patches in early June. The lightest compositions similar to the present-day winter precipitation (snow) are characteristic of the polygonal wedge ices (PWI) of the Central Yakutia. The most lightweight (from -30 to -34 % for δ 18 O, and from 240 to 275% for δ D) were established to be typical for the ancient PWI, dated by the first half of the Late Pleistocene (MIS 3-4). Heavier compositions (δ 18 O = -27.2±1.4, δD = -215.8±8.5, d exc = 1.7±3.1 %) with obvious features of evaporative fractionation correspond to younger PWI (MIS 2-1). The heaviest compositions (δ 18 O = -12.2±0.7, δD = -99.2±4.7, d exc = -2.0±0.8 %) and high angular coefficients of approximating equations were determined in the investigated cave ices of sublimation origin, that implies the atmospheric origin of them. The current processes of evaporative fractionation are the most intensively reflected in the waters of aeolian lakes ( δ 18 O = -11.8±3.5, δD = -120.2±18.4, d exc = -25.8±10.5 %), and the compositions are described by the regression equation 5D = 5.52 δ 18 O - 54.12 (R 2 = 0.97). The phenomenal objects of the cryogenic-eolian landscapes of the Central Yakutia are high-debit underground sources. Among all other components of the water flows, composition of these sources is the most stable (δ 18 O = -21.6±0.8, δD = -172.6±5.1, d exc = 0.23±3.0 %). The regression of compositions of the largest underground source Bulus is approximated by the equation 5D = 6.31 δ 18 O - 36.7 (R 2 = 0.78), that is indicative to significant evaporative fractionation and close relation with the aeolian lakes in the alimentation area.

The present-day regional level of various trace elements contents together with characteristics of isotopic composition was for the first time estimated in seasonal snow cover of Altai. As a background territory, the State Nature Biosphere reserve «Katunsky» had been chosen. This reserve is included into the World network of biosphere reserves under the UNESCO Program «Man and biosphere». The route snow survey had been carried out at the end of February 2014 since this is a period of maximum snow accumulation. The snow survey involved evaluation of snow storages, stratigraphic analysis of the snow cover, and layer-by-layer snow sampling for analysis of its trace element and isotopic compositions. Isotopic and stratigraphic analysis of visually selected layers of the snow cover revealed substantial variation in the values of δ18O and δD (the maximum difference between layers was 120.1 and 15.3 ‰, respectively), while dexc changed within the range from 5.6 to 16.6 ‰. The weighted-mean values of the snowpack isotopic composition are the following: δ 18 O = −24.9 and δD = −188.9 ‰, and the isotopic ratio of oxygen and deuterium is described by the equation δD = 8,3δ 18 О + 18.9. The analysis of microelement composition of the snow samples made with the use of the crustal enrichment factor (EFc) and correlation matrix allowed determination of elements (Ba, Be, V, Co, Li, Mn, Ni, Sr, Tl, Th, U и Cs) released into the atmosphere above the territory under investigation mainly with particles of fly ash, in which the ratio of elements corresponds to the regional natural sources – soils and underlying rocks. It was shown that the main part of elements Ag, As, Bi, Cu, Mo, Sb, Zn come preferably from anthropogenic sources which are non-ferrous metallurgy enterprises of East Kazakhstan and pits of operating and abandoned mines of Rudny Altai.

Over the past three decades, several general circulation models of the atmosphere and ocean (atmospheric and oceanic general circulation models – GCMs) have been improved by modeling the hydrological cycle with the use of isotopologues (isotopes of water) HDO and H2 18O. Input parameters for the GCM models taking into account changes in the isotope composition of atmospheric precipitation were, above all, the results obtained by the network GNIP – Global Network of Isotopes in Precipitation. At different times, on the vast territory of Russia there were only about 40 simultaneously functioning stations where the sampling of atmospheric precipitation was performed. In this study we present the results of the isotope composition of samples taken on the foothills of the Altai during two winter seasons of 2014/15 and 2015/16. Values of the isotope composition of precipitation changed in a wide range and their maximum fluctuations were 25, 202 and 18‰ for δ18О, dexc and δD, respectively. The weighted-mean values of δ18О and δD of the precipitation analyzed for the above two seasons were close to each other (−21.1 and −158.1‰ for the first season and −21.1 and −161.9‰ for the second one), while dexc values differed significantly. The comparison of the results of isotope analysis of the snow cover integral samples with the corresponding in the time interval the weighted-mean values of precipitation showed high consistency. However, despite the similarity of values of δ18О and δD, calculated for precipitation and snow cover, and the results, interpolated in IsoMAP (from data of the GNIP stations for 1960–2010), the dexc values were close to mean annual values of IsoMAP for only the second winter season. According to the trajectory analysis (the HYSPLIT model), the revealed differences between both, the seasons, and the long-term average values of IsoMAP, were associated with a change of main regions where the air masses carrying precipitation were formed, namely, the North Atlantic (the winter season of 2014/15) and the inland areas with open ice-free water bodies (the season of 2015/16). Thus, with the correct interpretation of the results, the data on the snow cover isotope composition on the Altai foothills can be used as an alternative data sources instead of the GNIP data.

The article presents results of study of the isotope composition and pollen spectra of atmospheric precipitation and ice taken from marginal parts of Korumdu Glacier (North-Chu Ridge, the Altai Mountains). The study was aimed at identification of sources and ways of precipitation into the nival-glacial region of Altai. Investigation of the isotope composition of ice taken from the tongue of the Korumdu Glacier and summer precipitation in its basin has shown that here the isotope concentrations are much smaller than similar ones of the cold Belukha Glacier. The last one is located near the Korumdu Glacier. This difference can be explained by the fact that main source of moisture forming layers of relatively warm Korumdu Glacier is precipitation of the cold season while accumulation on the cold Belukha Glacier proceeds during the whole year mainly due to the most heavy precipitation of warm (from March to November) season. Analysis of the isotope composition and the air mass trajectories on the day of July 16, 2013 allowed conclusion that the air masses started their way in the Baltic Sea region and moved mainly along middle latitudes. On this way they underwent insignificant isotope fractionation. Synoptic analysis had shown that the main reason of precipitation on the area under investigation was a front of occlusion over the Altai. In addition, results of palynological analysis of precipitation allow identification sources of pollen in this region. With high probability we can assume that on that day the main sources of pollen in Altai precipitation are as follows: the Naryan-Mar area for Scots pine (Pinus sylvestris) pollen, tundra zones of the East European Plain for alder (Alnaster sp.) pollen and the steppe regions of Kazakhstan, and the West Altai for pollen grains – the dominant component of the pollen spectrum.

In an isoperibolic calorimeter with a stationary bomb, the value of the combustion energy of crystalline β-alanine (ΔcU0) was determined at 298.15 K, from which standard enthalpies of combustion (ΔcU0) and formation (ΔcU0) have been calculated. The obtained results are compared with literature data.

The enthalpy of the combustion of C60Br24 · 2Br2 has been measured using a rotating-bomb calorimeter as follows: Δ c H 0(C60Br24 · 2Br2, cr) = (−25986 ± 166) kJ/mol. The result has been used to calculate the standard enthalpy of formation, ΔfH 0(C60Br24 · 2Br2, cr) = (2375 ± 166) kJ/mol. The enthalpies of formation of C60Br24 (cr) and dissociation of the C-Br bond have been estimated. The latter value has been compared with enthalpies for the C-X (X = H, F, Cl, Br) bonds in fullerene derivatives and organic compounds.

The energies of combustion, Δ c U 0, of three amino acids: L-serine (I), L-arginine (II) and L-tyrosine (III) in the crystalline state at 298.15 K were determined using a static-bomb isoperibolic calorimeter. From these data, the enthalpies of combustion, Δ c H 0, and the enthalpies of formation, Δ f H 0, are calculated. The Δ f H 0 values are compared with the published data.

An estimation of changes in the precipitation over the Altai mountains in 1959-2016 was carried out using the Mann-Kendall-Sneyers test. It was found that the precipitation has a step change in 1980. The step change point of precipitation in the Altai mountains coincides with the beginning of «zonal epoch of elementary circulation mechanisms» for the Siberian sector according to Dzerdzeevskii’s classification. B.L. Dzerdzeevskii considered 41 subtypes of elementary circulation mechanisms (ECMs) based on analysis of maps of baric topography at the 500 hPa level. To reveal the role of various ECMs in the Altai precipitation, we calculated the contribution of the ECMs which correspond to the Siberian sector to the precipitation. It was found that the most significant contribution to the precipitation regime of the Altai mountains was provided by the «West zonal and southern meridional» circulation group. The maximal contribution to the precipitation of 2016 was given by the «West zonal and southern meridional» circulation group (26.8%). The precipitation of this ECM group is characterized by the heaviest isotope composition (δ18O -9.85‰ and δD -78.65 ‰) relatively to the values obtained for the other circulation groups. In the ECM of this group of circulations the precipitation is most often caused by southern cyclones coming from the Aral-Caspian region, the waters of which have the heaviest isotope composition.

An analysis is made of the meteorological conditions and of the formation sources of solid particles (dust) which are visually recorded in the layers of the ice core sampled by the joint Russian-Swedish expedition in 2001 in the saddle of Mt. Belukha of the Altai mountain massif (Katunsky Range).

The standard enthalpy of combustion of crystalline silver pivalate, (CH3)3CC(O)OAg (AgPiv), was determined in an isoperibolic calorimeter with a self-sealing steel bomb, ΔcH0 (AgPiv, cr)= −2786.9±5.6 kJ mol−1. The value of standard enthalpy of formation was derived for crystalline state: ΔfH0(AgPiv,cr)= −466.9±5.6 kJ mol−1. Using the enthalpy of sublimation, measured earlier, the enthalpy of formation of gaseous dimer was obtained: ΔfH0(Ag2Piv2,g)= −787±14 kJ mol−1. The enthalpy of reaction (CH3)3CC(O)OAg(cr)=Ag(cr)+(CH3)3CC(O)O.(g) was estimated, ΔrH0=202 kJ mol−1.

The enthalpy of combustion of crystalline fullerene fluoride C60F18 was determined in an isoperibolic calorimeter with a rotating platinized bomb, and the enthalpy of formation of the compound was calculated. The enthalpy of sublimation of C60F18 measured earlier was used to calculate the enthalpy of formation of fullerene fluoride in the gas phase and the mean enthalpy of dissociation of C-F bonds in this compound.

Considered is a source of solid particles (dust) that are visually observed in the layers of an ice core sampled by a joint Russian-Swiss expedition in 2001 in a saddle of Mount Belukha of the Altai mountain massif (the Katun Range, Altai Republic). Based on analysis of the archival data and a synoptic situation in the Central Asian region, it was found that the most likely source of solid aerosol particles in a glacier layer dated by 1985 is the uplift and transport of the surface soil layer by a whirlwind, observed on August 7, 1985, in the settlement of Dolino, Rubtsov region, Altai Territory.

A rotating-bomb calorimeter was used to measure the energy of combustion of crystalline fullerene chloride C60Cl30 · 0.09Cl2, Δc U° = (−24474 ± 135 kJ/mol). The result was used to calculate the standard enthalpy of formation, Δf H° (C60Cl30, cr) = 135 ± 135 kJ/mol, and the C-Cl bond energy, 195 ± 5 kJ/mol. The C-X (X = F, F, Cl, and Br) bond energies in fullerene C60 derivatives and other organic compounds are compared.

The energy of combustion of crystalline 1,2,3,4-tetrachlorodibenzo-p-dioxine (-5122.9 ± 7.4 kJ/mol) was measured using an isothermic-shell calorimeter with a rotating platinum plated bomb. The result was used to calculate the enthalpy of combustion (-5120.4 ± 7.4 kJ/mol) and formation (−267.8 ± 7.6 kJ/mol) for the crystalline state. The enthalpy of sublimation was measured using a Calvet microcalorimeter at 411.5 K (116.0 ± 2.6 kJ/mol); recalculation to T = 298.15 K gave 118.7 ± 2.6 kJ/mol. The enthalpy of formation of 1,2,3,4-tetrachlorodibenzo-p-dioxine in the gas state was calculated (−149.1 ± 8.0 kJ/mol)

The standard molar enthalpy of combustion of 2-chlorodibenzo- p -dioxin was redetermined using the sample of high purity by rotating-bomb calorimetry: Δ c H 0 m (cr)=−(5558.2±3.5) kJ · mol −1 . The values of standard molar enthalpies of formation were derived for crystalline and gaseous states: Δ f H 0 m (cr)=−(187.9±3.8) kJ · mol −1 and Δ f H 0 m (g)=−(90.7±3.8) kJ · mol −1 .

The energy of combustion Δ c U 0 of fluorinated graphite CF0.96 has been determined using an isoperibolic calorimeter with a rotating platinized bomb and the enthalpy of formation Δ f H 0 thereof has been calculated. The enthalpy of the dissociation of the C-F bond has been calculated from the obtained value of Δ f H0(CF0.96) and compared with analogous values for the previously investigated C60 fullerene fluorides.

The standard molar enthalpy of combustion of fluorinated fullereneC60F48 was determined by rotating-bomb calorimetry,ΔcHmo = − (24638 ± 163)kJ · mol − 1. Using this result and the standard molar enthalpy of sublimation,ΔsubHmo = (109 ± 7)kJ · mol − 1, the values of the standard molar enthalpies of formation of C60F48in the crystalline and gaseous states were found to be − (7563 ± 166)kJ · mol − 1and − (7454 ± 166)kJ · mol − 1, respectively. The enthalpy of reaction C60F48(g) = C60(g) + 48F(g) was calculated,ΔrHmo (298.15 K) = (13800 ± 167)kJ · mol − 1, orΔrHmo (298.15K ) / 48 = (287.5 ± 3.5)kJ · mol − 1.

The standard molar enthalpy of combustion of crystalline 2,3-dichlorodibenzo-p-dioxin was determined by rotating-bomb calorimetry: ΔcHm°=−(5406.4±6.6) kJ·mol−1. Using this result and the standard molar enthalpy of sublimation, ΔsubHm°=(108.6±1.0) kJ·mol−1, the values of the standard molar enthalpies of formation of 2,3-dichlorodibenzo-p-dioxin in the crystalline and gaseous states were found to be −(220.5±6.8) kJ·mol−1and −(111.9±6.9) kJ·mol−1, respectively. The standard molar enthalpy of formation of gaseous 2,3,7,8-tetrachlorodibenzo-p-dioxin was estimated: ΔfHm°(g)≈−164.6 kJ·mol−1.

The standard molar energy of combustion of crystalline 2-chlorodibenzo-p-dioxin was determined by rotating-bomb calorimetry: ΔcUm°= −(5573.6±2.8)kJ·mol−1. The standard molar enthalpy of sublimation was measured in a Calvet microcalorimeter: ΔsubHm°= (97.24±0.55) kJ·mol−1. Using these results, the values of the standard molar enthalpies of formation of 2-chlorodibenxo-p±dioxin in the crystalline and gaseous states were found to be −(171.3 ±3.2)kJ·mol−1and −(74.1±3.3)kJ·mol−1and −(74.1-3.3)kJ·mol−1, respectively.

In recent years, some general circulation models have been improved by using stable water isotopologues, such as HDO (δD) and H2 18O (δ18O). In this paper, the results of a study of the isotopic composition of precipitation sampled in the winter seasons of 2014-2015 and 2015-2016 in Altai foothills are presented. The isotopic composition varied greatly: from -17.4 ‰ to -30.63 ‰ for δ18O and from -132.1 ‰ to -235.0 ‰ for δD in 2014-2015; from -15.9 %" to -26.8 ‰ for δ18D and from -118.5 ‰ to -207.7 ‰ for δD in 2015-2016. The weighted average values of δ18O and δD for both seasons were close to each other (-21.2 ‰ and -160.1 ‰ for the first season and -20.4 ‰ and -157.5 ‰ for the second season), while the values of dexc differed significantly. A trajectory analysis (by the Hybrid Single Particle Lagrangian Integrated Trajectory - (HYSPLIT) model) has shown that the difference in the isotopic composition of the precipitation is largely associated with the change of the main source regions of atmospheric moisture, namely, the change of the North Atlantic waters (the 2014-2015 winter season) for the inland waters (the 2015-2016 winter season). A comparison of the results of an isotopic analysis has shown good agreement with data of the Global Network of Isotopes in Precipitation (GNIP) interpolated for 1960-2010. Thus, with a proper interpretation the data of the isotopic composition of the winter precipitation in Altai foothills can be used for this territory as an alternative source of the GNIP network data.

The standard molar enthalpy of combustion of fluorofullerene C60F36 was determined by rotating-bomb calorimetry, ΔcH°m = −24692 ± 199 kJ·mol-1. Using this result and the standard molar enthalpy of sublimation, ΔsubH°m = 139 ± 8 kJ·mol-1, the values of the standard molar enthalpies of formation of C60F36 in the crystalline and gaseous states were found to be −5362 ± 201 kJ·mol-1and −5223 ± 201 kJ·mol-1, respectively. The enthalpy of reaction C60F36(g) = C60(g) + 36F(g) was calculated, ΔrH°m(298.15 K) = (10617 ± 202) kJ·mol-1, or 294.9 ± 5.6 kJ·mol-1 per one C−F bond. The comparison with the enthalpy of reaction C60F48 = C60(g) + 48F(g), ΔrH°m(298.15 K) = 287.5 ± 3.5 kJ·mol-1 per C−F bond leads to a preliminary conclusion that C−F bond enthalpy decreases with amount of F atoms attached to the fullerene cage.

In the present research we discuss a role of volcanic activity in Altai thermal regime. Here we analyses the sulfate and temperature data reconstructed from the natural paleoarchive – ice core from the Belukha Mountain saddle. Sulfate ice-core reconstructions can serve as volcanic markers. The both – sulfate and temperature reconstructions – are for the last 750 years. As the characteristic of volcanic activity we consider Volcanic Explosivity Index (VEI), Dust Veil Index (DVI) and Ice core volcanic index (IVI). The analysis was done using wavelet analysis and analysis of wavelet cross coherence and phase. As the result, we conclude that observed increases in the values of the indexes VEI, DVI, IVI basically correspond to decreases of temperature and increases of sulfate concentrations. This confirms the dependence of changes in the thermal regime of the Altai from volcanic activity. But in the 1750–1850 years period there is a delay of the changes in temperature with respect to the changes in volcanic activity. We suggest that it can be due to the superposition of the influence of solar and volcanic activity on changes in the thermal regime of Altai.

Paleotemperature time series reconstructed from δ¹⁸O changes in Belukha ice core were expanded into several heteroperiodic sinusoidal functions with the help of the spectral Fourier analysis. The main harmonics selected from obtained periodogram have allowed to perform (without taking into account the contribution of changes in the existing anthropogenic load) scenario forecasts of average annual (from March to November) temperature changes in the Altai region in the nearest future (until 2050). Forecast shows that a cold phase came to Altai since 2008 reaches its maximum by 2020. Then after the 15-year period of temperature increase a cold phase will come back after 2035. Our forecast agrees very well with the forecast made from the natural climatic variability (for example, the change of global temperature for the last 150 years).

The energies of combustion of perfluoro(2-methyl-3-oxa)hexanoic and perfluoro(2,5-dimethyl-3,6-dioxa)nonanoic acids are for the first time measured in a calorimeter with a rotating platinized bomb and used to calculate the standard enthalpies of formation of these compounds in the liquid state. Based on the enthalpies of formation, the contribution from the [-CF2OCF(CF3)-] group to the enthalpies of formation of perfluoro acids is calculated.

The present paper discusses an urgent need for Central Asian countries and the Asian part of Russia to develop uniform principles for monitoring and creating a reliable data bank on water quality. In Russia and other countries of the former Soviet Union, the control over water quality and quantity is conducted by a number of state agencies. These agencies have different standards for water sampling and analysis which cause substantial problems in coordination of their activities. This coordination can be improved by the establishment of water standards and the development of a unified technique for water sampling, analysis and processing of the data.

A key part of the analysis of inland water systems is the estimation of mass balances around the water body. There are several important compartments, and each requires different methods to estimate inputs, outputs and net accumulation or loss.

The enthalpies of formation of dibenzo-p-dioxin and its polychlorinated derivatives have been measured, and a complete set of the enthalpies of formation has been constructed.

The energy of combustion of perfluoro-2,7-dimethyloctane has been measured in a rotating bomb calorimeter, Δ c U 0 (1) = −3198.2 ± 8.6 kJ mol −1 . The enthalpy of formation, Δ f H 0 (1) has been obtained by combination of the experimental data with the accepted values for the enthalpies of formation of water, carbon dioxide and aqueous hydrofluoric acid.

Data on the thermochemistry of haloethanes are surveyed. The most reliable standard enthalpies of formation of 37 haloethanes are recommended on the basis of a critical analysis of the experimental results published up to 1980 inclusive (and partly in 1981). The constants of a computational scheme for the estimation of the enthalpies of formation of hitherto uninvestigated haloethanes have been evaluated by the method of least squares. The enthalpies of formation of 210 haloethanes containing H, F, Cl, and Br have been calculated with the aid of these constants. The bibliography includes 131 references.

The energies of combustion of two isomers of trifluorochlorobromoethane have been determined by rotating-bomb calorimetry. The values of the enthalpies of formation: ΔHfo(CF3CHClBr, g) = −(690.4 ± 4.9) kJ mol−1 and ΔHfo(CF2BrCHFCl, g) = −(644.8 ± 6.4) kJ mol−1 were derived. Using the latter value, the enthalpy of formation of trifluorochloroethylene CF2:CFCl was found to be −(500.0 ± 6.5) kJ mol−1.

The paper presents a brief climatic characteristic and statistical analysis on dynamics of thermal regime in Altai Mountains. The close correlation between temperature series of the Russian and northern part of Mongolian Altai was determined. It was found that the rate of temperature increase for the period under consideration (1940–2008) ranged from 0.19 to 0.53 °С/10 years, and the most significant increase was registered during the cold seasons. During the maximum global warming (1980–1999), a 2–4.5 times increase of annual average temperature was observed as compared to the period of 1940–1979. The temperature series variations obtained with the Welch's method and wavelet analysis correspond to the periods of North Atlantic Oscillation and solar activity variation.