28 research outputs found

    Column formation and hysteresis in a two-fluid tornado

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    Ponencia de: 6th International Conference Heat and Mass Transfer and Hydrodynamics in Swirling Flows 21–23 November 2017, Novosibirsk, Russian FederationThis experimental and numerical study addresses a flow of water and sunflower oil. This flow is driven by the rotating lid in a sealed vertical cylinder. The experiments were performed in a glass container with a radius of 45 mm and a height of 45 mm with the water volume fraction of 20%. Different densities and immiscibility of liquids provide the stable and sharp interface. At the rest, the interface is flat and horizontal. As the rotation speeds up, a new water-flow cell emerges near the bottom center. This cell expands and occupies almost the entire water domain while the initial water circulation shrinks into a thin layer adjacent to the interface. The water, rising near the container axis, strongly deforms the interface (upward near the axis and downward near the sidewall). A new oil-flow cell emerges above the interface near the axis. This cell disappears as the interface approaches the lid. The water separates from the sidewall, reaches the lid, and forms a column. As the rotation is decreased, the scenario reverses, but the flow states differ from those for the increasing rotation, i.e., a hysteresis is observed. The numerical simulations agree with the experiment and help explain the flow metamorphoses.Russian Science Foundation 14-29-0009

    Assessment of the role of the state in the management of mineral resources

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    Mineral resources as natural capital can be transformed into human, social and physical capital, that guarantees the sustainable development of a country, exclusively through professional public management. Public management of a country's mineral resource potential is seen as an element of transnational governance. Regulation involves the use of laws, rules and regulations within the jurisdictional and sectoral capabilities of the state, minimizing its involvement as a producer. The features of the ideology of economic liberalism, which polarizes the societies of raw material producing countries by imposing austerity, as well as lowering trade barriers have been studied. The analysis of the influence of the radical new order of neoliberal world ideology on the development of the extractive sector and the strengthening of state regulation has been presented

    The Toroid Moment of Majorana Neutrino

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    If neutrino is the Majorana particle it can possess only one electromagnetic characteristic, the toroid dipole moment (anapole) in the static limit and nothing else. We have calculated the diagonal toroid moment (form factor) of the Majorana neutrino by the dispersion method in the one-loop approximation of the Standard Model and found it to be different from zero in the case of massive as well as massless neutrinos. All external particles are on the mass shells and there are no problems with the physical interpretation of the final result. Some manifestations of the toroid interactions of Majorana neutrinos, induced by their toroid moments, are also remarked.Comment: 22 pages, 1 table and 3 EPS-figures included, uses prd.sty, preprint.sty, aps.sty and epsfig.sty (RevTeX is used), major conceptual changes of E2-96-53 are include

    Measurement, Collaborative Learning and Research for Sustainable Use of Ecosystem Services: Landscape Concepts and Europe as Laboratory

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    A luminescence spectroscopy study of new Li2BaAl2F10\mathrm{Li_2BaAl_2F_{10}} single crystal

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    Large Li2_2BaAl2_2F10_{10} single crystals of optical quality were grown using the vertical Bridgman method. X-ray diffraction method was used to determine the crystal structure (orthorhombic symmetry Cmc21_1), lattice parameters, atomic coordinates. The luminescent properties were investigated using selective photoexcitation by synchrotron radiation (E = 3.7–21 eV, T = 8 K, time integrated and time-resolved spectra) as well as upon excitation with unfiltered X-ray beam (synchrotron radiation or X-ray tube). We revealed both the broadband luminescence at Em_m = 4.0 eV (Eex_{ex}=11.72 eV) attributed to the radiative annihilation of self-trapped excitons (STE) and the excitonic-type near-defect luminescence at Em_m = 3.0–3.2 eV (Eex_{ex}=11.25 eV) attributed to radiative relaxation of electronic excitations in nonequivalent structural units of the crystal lattice. The fast exponential component with lifetime of 5.6 ns, a low-intensity intermediate component with a lifetime of 75–100 ns, a constant level — pedestal (sum of the micro- and millisecond decay components) were revealed in luminescence decay kinetics. The electronic structure parameters (bandgap = 13.0 eV, low-energy onset of the intrinsic host absorption Ec_c = 11.2 eV), the energy threshold for the excitation of STE-luminescence ( Eth_{th} = 11.2 eV) are determined from spectroscopic data. Thermoluminescence (TL) has been studied (90–350 K) using spectral-integral regime. Four partially overlapping TL glow peaks were revealed, their deconvolution was done and thermal activation parameters were determined using TGCD method

    Bromination of bis(pyridin-2-yl) diselenide in methylene chloride: the reaction mechanism and crystal structures of 1H-pyridine-2-selenenyl dibromide and its cycloadduct with cyclopentene (3aSR,9aRS)-2,3,3a,9a-tetrahydro-1H-cyclopenta[4,5][1,3]selenazolo[3,2-a]pyridinium bromide

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    1H-Pyridine-2-selenenyl dibromide, C5H5NSeBr2, 1, is a product of the bromination of bis(pyridin-2-yl) diselenide in methylene chloride recrystallization from methanol. Compound 1 is essentially zwitterionic: the negative charge resides on the SeBr2 moiety and the positive charge is delocalized over the pyridinium fragment. The C—Se distance of 1.927 (3) Å is typical of a single bond. The virtually linear Br—Se—Br moiety of 178.428 (15)° has symmetrical geometry, with Se—Br bonds of 2.5761 (4) and 2.5920 (4) Å, and is twisted by 63.79 (8)° relative to the pyridinium plane. The Se atom forms an intermolecular Se...Br contact of 3.4326 (4) Å, adopting a distorted square-planar coordination. In the crystal, molecules of 1 are linked by intermolecular N—H...Br and C—H...Br hydrogen bonds, as well as by non-covalent Se...Br interactions, into a three-dimensional framework. (3aSR,(9aRS)-2,3,3a,9a-Tetrahydro-1H-cyclopenta[4,5][1,3]selenazolo[3,2-a]pyridinium-9 bromide, C10H12NSe+·Br−, 2, is a product of the cycloaddition reaction of 1 with cyclopentene. Compound 2 is a salt containing a selenazolopyridinium cation and a bromide anion. Both five-membered rings of the cation adopt envelope conformations. The dihedral angle between the basal planes of these rings is 62.45 (11)°. The Se atom of the cation forms two additional non-covalent interactions with the bromide anions at distances of 3.2715 (4) and 3.5683 (3) Å, attaining a distorted square-planar coordination. In the crystal, the cations and anions of 2 form centrosymmetric dimers by non-covalent Se...Br interactions. The dimers are linked by weak C—H...Br hydrogen bonds into double layers parallel to (001)

    COVIDomic:A multi-modal cloud-based platform for identification of risk factors associated with COVID-19 severity

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    Coronavirus disease 2019 (COVID-19) is an acute infection of the respiratory tract that emerged in December 2019 in Wuhan, China. It was quickly established that both the symptoms and the disease severity may vary from one case to another and several strains of SARS-CoV-2 have been identified. To gain a better understanding of the wide variety of SARS-CoV-2 strains and their associated symptoms, thousands of SARS-CoV-2 genomes have been sequenced in dozens of countries. In this article, we introduce COVIDomic, a multi-omics online platform designed to facilitate the analysis and interpretation of the large amount of health data collected from patients with COVID-19. The COVIDomic platform provides a comprehensive set of bioinformatic tools for the multi-modal metatranscriptomic data analysis of COVID-19 patients to determine the origin of the coronavirus strain and the expected severity of the disease. An integrative analytical workflow, which includes microbial pathogens community analysis, COVID-19 genetic epidemiology and patient stratification, allows to analyze the presence of the most common microbial organisms, their antibiotic resistance, the severity of the infection and the set of the most probable geographical locations from which the studied strain could have originated. The online platform integrates a user friendly interface which allows easy visualization of the results. We envision this tool will not only have immediate implications for management of the ongoing COVID-19 pandemic, but will also improve our readiness to respond to other infectious outbreaks
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