Publications by authors named "Volkov S"

Solvothermal reaction of magnesium nitrate and boron oxide in ,-dimethylformamide produced a number of particularly complex supramolecular magnesium borates. Five topologically different types of negatively charged {Mg@[Bφ]}-clusters, φ = O, OH, were observed with the magnesium cation as a core and octadecaborate anions as shells. The clusters assemble common borate polyhedra forming 1D chains, a 2D mesoporous layer, and 3D mesoporous frameworks with an effective channel width of up to 16 Å.

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It is generally accepted that aragonite crystals of biogenic origin are characterized by significantly higher twin densities compared to samples formed during geological processes. Based on our single crystal X-ray diffraction (SCXRD) and transmission electron microscopy (TEM) study of aragonite crystals from various localities, we show that in geological aragonites, the twin densities are comparable to those of the samples from crossed lamellar zones of molluscs shells. The high twin density is consistent with performed calculations, according to which the Gibbs free energy of twin-free aragonite is close to that of periodically twinned aragonite structure.

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Flexible crystal() structures, which exhibit() single-crystal()-to-single-crystal() (SCSC) transformations(), are attracting attention() in many applied aspects: magnetic() switches, catalysis, ferroelectrics and sorption. Acid treatment() for titanosilicate material() AM-4 and natural() compounds with the same structures led to SCSC transformation() by loss() Na, Li and Zn cations with large structural() changes (20% of the unit()-cell() volume()). The conservation() of crystallinity through complex() transformation() is possible due() to the formation() of a strong hydrogen bonding() system().

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Aim: To compare the efficiency of two surgical methods, holmium laser enucleation of prostate (HoLEP) and laparoscopic retropubic simple prostatectomy with clamping of internal iliac arteries and vesicourethral anastomosis [LPA+CIIA+VUA]) for treating of patients with benign prostatic hyperplasia (BPH) and type 2 diabetes mellitus (T2DM).

Materials And Methods: A total of 56 men with T2DM who underwent surgical treatment of BPH in the National Research Centre for Endocrinology of the Russian Ministry of Health (director - corresponding member of RAS Mokrysheva N.G.

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Multijet events at large transverse momentum () are measured at using data recorded with the CMS detector at the LHC, corresponding to an integrated luminosity of . The multiplicity of jets with that are produced in association with a high- dijet system is measured in various ranges of the of the jet with the highest transverse momentum and as a function of the azimuthal angle difference between the two highest jets in the dijet system. The differential production cross sections are measured as a function of the transverse momenta of the four highest jets.

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The structure of nucleons is multidimensional and depends on the transverse momenta, spatial geometry, and polarization of the constituent partons. Such a structure can be studied using high-energy photons produced in ultraperipheral heavy-ion collisions. The first measurement of the azimuthal angular correlations of exclusively produced events with two jets in photon-lead interactions at large momentum transfer is presented, a process that is considered to be sensitive to the underlying nuclear gluon polarization.

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The production of Z bosons associated with jets is measured in collisions at with data recorded with the CMS experiment at the LHC corresponding to an integrated luminosity of 36.3. The multiplicity of jets with transverse momentum is measured for different regions of the Z boson's , from lower than 10 to higher than 100.

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The double differential cross sections of the Drell-Yan lepton pair (, dielectron or dimuon) production are measured as functions of the invariant mass , transverse momentum , and . The observable, derived from angular measurements of the leptons and highly correlated with , is used to probe the low- region in a complementary way. Dilepton masses up to 1 are investigated.

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New sets of parameter tunes for two of the colour reconnection models, quantum chromodynamics-inspired and gluon-move, implemented in the pythia  8 event generator, are obtained based on the default CMS pythia  8 underlying-event tune, CP5. Measurements sensitive to the underlying event performed by the CMS experiment at centre-of-mass energies and 13, and by the CDF experiment at 1.96 are used to constrain the parameters of colour reconnection models and multiple-parton interactions simultaneously.

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A search is reported for pairs of light Higgs bosons () produced in supersymmetric cascade decays in final states with small missing transverse momentum. A data set of LHC collisions collected with the CMS detector at and corresponding to an integrated luminosity of 138 is used. The search targets events where both bosons decay into pairs that are reconstructed as large-radius jets using substructure techniques.

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The analysis of complexes formation of hydrogen peroxide molecule with DNA nucleic bases is carried out using methods of quantum chemistry. Optimized geometries of complexes are determined and the interaction energies that lead to complex formation are calculated. Comparison with the same calculations for water molecule is made.

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Three different platinum oxides are observed by in situ X-ray diffraction during electrochemical potential cycles of platinum thin film model electrodes on yttria-stabilized zirconia (YSZ) at a temperature of 702 K in air. Scanning electron microscopy and atomic force microscopy performed before and after the in situ electrochemical X-ray experiments indicate that approximately 20% of the platinum electrode has locally delaminated from the substrate by forming pyramidlike blisters. The oxides and their locations are identified as (1) an ultrathin PtO at the buried Pt/YSZ interface, which forms reversibly upon anodic polarization; (2) polycrystalline β-PtO, which forms irreversibly upon anodic polarization on the inside of the blisters; and (3) an ultrathin α-PtO at the Pt/air interface, which forms by thermal oxidation and which does not depend on the electrochemical polarization.

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The ability to derive temporal and spatial scales of "instantaneous" local temperature variations in a turbulent flame by means of coherent anti-Stokes Raman scattering (CARS) spectroscopy is demonstrated, for the first time to our knowledge. The measurements employed two CARS spectrometers with synchronized nanosecond pulse-repetitive lasers. The system was enabling to record, with a high temporal resolution of about 10 ns, series of single laser shot CARS spectra of N molecules from two spatially overlapped or displaced probe volumes as small as 0.

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Using glass crystallization and solid-state techniques, we were able to complete the family of salt-inclusion silver halide borates, AgBOX, by the X = Cl and I members. The new compounds are characterized by differential scanning calorimetry, single-crystal and high-temperature powder X-ray diffraction, optical spectroscopy, and density functional theory calculations. In all structures, the silver atoms exhibit strong anharmonicity of thermal vibrations, which could be modeled using Gram-Charlier expansion, and its asymmetry was characterized by the skewness vector.

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Measurements of the associated production of a W boson and a charm ( ) quark in proton-proton collisions at a centre-of-mass energy of 8 are reported. The analysis uses a data sample corresponding to a total integrated luminosity of 19.7 collected by the CMS detector at the LHC.

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A search for pairs of Higgs bosons produced via gluon and vector boson fusion is presented, focusing on the four b quark final state. The data sample consists of proton-proton collisions at a center-of-mass energy of 13 TeV, collected with the CMS detector at the LHC, and corresponds to an integrated luminosity of 138  fb^{-1}. No deviation from the background-only hypothesis is observed.

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Consisting of two fatty acyl groups, phospholipids are a vital part of vegetable oils and the source of essential fatty acids. Moreover, phospholipids influence oxidative and flavor stability and color evolution of vegetable oils, and their quantification has a significant role in the quality assessment of oils. In this study, we proposed a new highly efficient, affordable, environmentally friendly, and simple approach for the evaluation of phospholipid concentrations based on potentiometric multisensor systems coupled with chemometric data processing.

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Proton-proton interactions resulting in final states with two photons are studied in a search for the signature of flavor-changing neutral current interactions of top quarks (t) and Higgs bosons (H). The analysis is based on data collected at a center-of-mass energy of 13 TeV with the CMS detector at the LHC, corresponding to an integrated luminosity of 137  fb^{-1}. No significant excess above the background prediction is observed.

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Multiparticle azimuthal correlations of prompt D^{0} mesons are measured in Pb-Pb collisions at a nucleon-nucleon center-of-mass energy of sqrt[s_{NN}]=5.02  TeV. For the first time, a four-particle cumulant method is used to extract the second Fourier coefficient of the azimuthal distribution (v_{2}) of D^{0} mesons as a function of event centrality and the D^{0} transverse momentum.

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A search for resonances decaying into a W boson and a radion, where the radion decays into two W bosons, is presented. The data analyzed correspond to an integrated luminosity of 138  fb^{-1} recorded in proton-proton collisions with the CMS detector at sqrt[s]=13  TeV. One isolated charged lepton is required, together with missing transverse momentum and one or two massive large-radius jets, containing the decay products of either two or one W bosons, respectively.

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Article Synopsis
  • A search for exclusive two-photon production via photon exchange in proton-proton collisions was conducted using data from the LHC in 2016, focusing on events with intact protons.
  • The analysis aimed to select events with a diphoton invariant mass above 350 GeV, ensuring both protons remained intact to minimize interference from strong interactions.
  • No events meeting the criteria were found, which allowed researchers to set new limits on two anomalous four-photon coupling parameters, revealing |ζ_{1}|<2.9×10^{-13} GeV^{-4} and |ζ_{2}|<6.0×10^{-13} GeV^{-4} at a 95% confidence level.
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The B_{c}^{+} meson is observed for the first time in heavy ion collisions. Data from the CMS detector are used to study the production of the B_{c}^{+} meson in lead-lead (Pb-Pb) and proton-proton (pp) collisions at a center-of-mass energy per nucleon pair of sqrt[s_{NN}]=5.02  TeV, via the B_{c}^{+}→(J/ψ→μ^{+}μ^{-})μ^{+}ν_{μ} decay.

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Using a data sample of proton-proton collisions collected by the CMS experiment at the LHC in 2017 and 2018 with an integrated luminosity of , the and decays are observed with significances exceeding 5 standard deviations. The resulting branching fraction ratios, measured for the first time, correspond to and , where the last uncertainty in the first ratio is related to the uncertainty in the ratio of production cross sections of and mesons, .

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A search for low-mass dilepton resonances in Higgs boson decays is conducted in the four-lepton final state. The decay is assumed to proceed via a pair of beyond the standard model particles, or one such particle and a boson. The search uses proton-proton collision data collected with the CMS detector at the CERN LHC, corresponding to an integrated luminosity of 137 , at a center-of-mass energy .

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The spectra measurements of charged hadrons produced in the shower of a parton originating in the same hard scattering with a leptonically decaying Z boson are reported in lead-lead nuclei (Pb-Pb) and proton-proton (pp) collisions at a nucleon-nucleon center-of-mass energy of 5.02 TeV. Both Pb-Pb and pp data sets are recorded by the CMS experiment at the LHC and correspond to an integrated luminosity of 1.

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