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The age of formation of the explosion pipes of the Chapinskii complex in the Chingasan magmatic belt in the northern part of the Yenisei Ridge is determined. U–Pb dating of zircon megacrysts from alkaline ultramafic rocks has established the values of 657.7 ± 13.4 and 647.6 ± 9.7 Ma for the Natalyinskaya pipe and Pipe no. 3, respectively. The intrusion of alkaline ultramafic explosion pipes of the Chapinskii complex corresponds to the time of manifestation of alkaline ultramafic magmatism along the southern and southwestern margin of the Siberian Craton. [ABSTRACT FROM AUTHOR]

This paper presents new materials and summarizes existing ones on archeoseismology studies of stony walls conducted in the Alabash-Konurolyong intramountain depression (southwestern Issyk-Kul Lake region, the northern Tien Shan). The remnants of a sublatitudinal stone wall north of the village of Kyoksay, the remnants of buildings on the Duvana pass, the "long" submeridional wall north of the village of Alabash, and ruins of the fortress of the same name located on the Alabash pass have been studied. The deformations allow us to proceed to quantitative characteristics of two seismic events that occurred in the 15th and 18th centuries. The significant PGV values (on average, 1–3 m/s) are in good agreement with results of an analysis of data on the strong ground motions and correspond to the nearest near-fault zone. These values, in accordance with the morphostructural and other paleoseismologic data, point to the vicinity (within the limits of a few kilometers) of the corresponding seismogenic fault generating them and to the development of thrust deformations of compression. Paleoseismologic data, in particular, the results of PGV value assessments, indicate the significantly larger seismic hazard of the southern shore of the Issyk-Kul Lake depression than is shown in the modern map of seismic hazards of Kyrgyzstan. We assess seismic intensity values for our investigated localities as I = 9.0 ± 0.5. Thus, according to preliminary paleoseismology data, the seismicity level of the southern part of the Issyk-Kul Lake basin is analogous to the seismicity of its northern part. These data can be used in reevaluating the seismic hazard of the investigated territory. [ABSTRACT FROM AUTHOR]

A convenient and affordable synthetic pathway for obtaining new α-aminoamidines starting from aminonitriles is proposed. The α-aminoamidines obtained can be applied as substrates for further transformations and synthesis of imidazole- and pyrimidine-containing building blocks. [ABSTRACT FROM AUTHOR]

For the first time, a monitoring was carried out for assessing the volume of the ice of the Peretolchin Glacier in the Munku-Sardyk mountain range (Eastern Sayan) using georadar profiling both directly to measure the thickness of the ice and to refine the parameters of mathematical models for determining the volume of the glacier. Based on results of the area radar survey, the volume of the various structures of the glacier (firn, the main icy body, and bottom moraines) was assessed. 3D models of these components of the glacier have been constructed. It was found that, in comparison with results of georadar profiling for other glaciers, the modern bed of the Peretolchin Glacier consists of deposits of the previous glaciation which ended 11 ka. Measurements of the ice thickness on the northern Peretolchin Glacier were made in June 2014, and in May 2016 and 2017, with a constant increase in the study area using the Oko-2 radar with the ABDL Triton antenna unit at 100 MHz. Maps of the ice thickness of the Peretolchin Glacier were updated, and its volume was determined, equal to 0.007 ± 0.0001 km3. The section of the glacier of direct study (the lower open part) measures 0.00297 km3. The method of sections, taking into account the relief of the glacier from additional profiles, proved to be the most accurate. In the surveyed portion, the proportion of firn, the ice and the bottom moraine makes up 25%, 29 and 46%, respectively. On the other hand, the proportion of the clean ice reduces from the middle part of the glacier to its bottom. Over more than 100 years, the Peretolchin Glacier (northern) has decreased in length, area and volume by factors of 1.75, 2.9 and 3.71, respectively. It has been established that the rate of reduction of the Peretolchin Glacier has been increasing since 2009. [ABSTRACT FROM AUTHOR]

We have studied paleoseismicity along the adyr (piedmont) Kokonadyr–Tegerek fault zone in the SW Issyk-Kul region. We have shown that although earthquake slip continues in the tectonic contact zone between the Paleozoic rocks of the Kokonadyr–Tegerek uplift and the Quaternary deposits of the Alabash–Konuroleng trough, still most earthquake-generating ruptures visible at the surface are moving for some hundreds of meters southward from the abovementioned adyr fault. This process leads to the formation of multislip earthquake scarps and compensation grabens behind them. Radiocarbon dating identified four large Holocene earthquakes along the Kokonadyr–Tegerek fault zone that occurred during the following time spans: 1771‒1785, 1440‒1515, as well as probably 2310–745 B.C. and 6400–5300 B.C. Judging from the parameters of these ruptures, or earthquake scarps, their magnitudes were greater than or equal to 7 and the intensity of shaking was Io ≥ IX. Vigorous seismic activity has gone on along the Kokonadyr–Tegerek fault zone since at least the Middle Quaternary. The relevant evidence includes uplifted and abandoned valleys of this age in the eponymous uplift and considerable accumulations of lacustrine deposits in the northern Alabash–Konuroleng depression. The thick sedimentary sequence was caused by glacier melting on the northern slope of the Terskei Ala-Too mountain range, while the abandoned valleys indicate considerable tectonic damming. The most suitable model to explain the formation of adyrs (piedmont areas or foothills) in the southern Issyk-Kul basin seems to be a model that envisages a low-angle northward propogating or southward dipping main fault that is complicated with reverse movements. All the materials acquired in this study can be used to develop a new Earthquake Hazard Map for the Republic of Kyrgyzstan. [ABSTRACT FROM AUTHOR]

A new spiro derivative of dihydro-1,2,3-triazolo[1,5-a]pyrimidine - 5'-amino-6'-cyano-4'H-spiro[cyclohexane-1,7'-[1,2,3]triazolo[1,5-a]-pyrimidine]-3'-carboxamide - was prepared by three-component reaction of 5-amino-1,2,3-triazole-4-carboxamide with malononitrile and cyclohexanone; the structure of product was established by X-ray analysis. Microwave activation and conventional heating showed the formation of single product and the same direction of heterocyclization. Available literature data concerning similar reactions using 3-amino-1,2,4-triazole or 2-aminobenzimidazole were reinvestigated experimentally with consideration of alternative structures; structures of products were studied by NMR including NOE experiments. [ABSTRACT FROM AUTHOR]

Presented are the results obtained from radar profiling of the Peretolchin glacier in the Munku-Sardyk mountain range in the south of Siberia (June 2014 and May 2016) using georadar OKO-2 with the ABDL Triton antenna unit operating at the radiation frequency of 50 and 100 MHz. The ice thickness was determined from the profiles and the ice volumes from the cross-sectional areas and distances between profiles. The ice volume was calculated for the body of the Peretolchin glacier to be 0.007 ± 0.0019 km3. An analytical method was also used to determine the ice volume according to the type and area of glacier. It is established that the correlation between the glacier volume and area is expressed by a power function V = kSp. The mean ice volume, calculated with due regard for different coefficients, was 0.0061 km3. The GlabTop model that assumes the cross-sectional form of the glacier was used to infer the ice volume: the mean volume for two cross-sections (parabolic and elliptic) was 0.0073 km3. It is found that over 110 years since the start of the investigation into the morphology of the Peretolchin glacier, it has increased twice in its length and in area, its volume has decreased by a factor of 3.7, and the lower boundary of the open part of the glacier has risen 184 meters during that period. [ABSTRACT FROM AUTHOR]

The article offers information on the localization of a pre-instrumental earthquake epicenter based on the analysis of coseismic deformation in soft deposits. It states that the coseismic deformations presented by ruptures and different types of seismites are well preserved in the sedimentary sections. It mentions that the investigation of them is important for localization of seismic event epicenters in the pre-instrumental period, for which traditional macroseismic descriptions are lacking.

The article offers information on the new electronic map that introduces the compiled database of active faults on Southeastern Siberia during the Neogene-Quaternary. It mentions that the map will be used for data gathering, critical interpretation, and assessment of seismic regularities and hazard in the seismotectonic process based on the active faults' geological-structural, hygrogeological and seismological cyles. It also discusses the three degree of trustworthiness used in differentiating the active faults which are represented in figures such as kinematics, activity degree, and time of last activation.

A generator of a pulse voltage with an amplitude of up to 1 MV based on a ten-stage voltage multiplier is described. The generator contains a control panel, a unit for periodical triggering of spark gaps in the generator stages, and a rectifier outputting a voltage of ± 50 kV for charging capacitors in stages. The generator has an output discharge capacitance of 500 pF, a stored energy of 250 J, a self-inductance of <0.7 μH, a guaranteed service life of 105 charging-discharging cycles, a rise time of the first voltage half-wave of 15 ns at a load of 200 pF, and a repetition rate of 1 Hz. To reduce the self-inductance of the source, insulating housings of capacitors and spark gaps are used in its layout. [ABSTRACT FROM AUTHOR]

The condensation of 4,4,4-trifluoro-1-phenylbut-1-en-3-one with 2-aminobenzimidazole, 3-amino-1,2,4-triazole, and 5-aminotetrazole gives hydroxy-substituted tetrahydro derivatives of pyrimido[1,2-a]benzimidazole, and of 1,2,4-triazolo-, and tetrazolo[1,5-a]pyrimidine. Dehydration of them to the corresponding dihydroazolopyrimidines has been carried out. An X-ray structural investigation was carried out and the molecular structure of 5-hydroxy-7-phenyl-5-trifluoromethyl-4,5,5,7-tetrahydrotetrazolo[1,5-a]pyrimidine is discussed. [ABSTRACT FROM AUTHOR]