Publications by authors named "V A Krapivin"

Studying complexes of cryptic or pseudocryptic species opens new horizons for the understanding of speciation processes, an important yet vague issue for the digeneans. We investigated a hemiuroidean trematode across a wide geographic range including the northern European seas (White, Barents, and Pechora), East Siberian Sea, and the Pacific Northwest (Sea of Okhotsk and Sea of Japan). The goals were to explore the genetic diversity within through mitochondrial ( and genes) and ribosomal (ITS1, ITS2, 28S rDNA) marker sequences, to study morphometry of maritae, and to revise the life cycle data.

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Crystal lattice fluctuations, which are known to influence phase transitions of quantum materials in equilibrium, are also expected to determine the dynamics of light-induced phase changes. However, they have only rarely been explored in these dynamical settings. Here we study the time evolution of lattice fluctuations in the quantum paraelectric SrTiO, in which mid-infrared drives have been shown to induce a metastable ferroelectric state.

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We report ultrafast x-ray scattering experiments of the quasi-1D charge density wave (CDW) material (TaSe_{4})_{2}I following ultrafast infrared photoexcitation. From the time-dependent diffraction signal at the CDW sidebands we identify a 0.11 THz amplitude mode derived primarily from a transverse acoustic mode of the high-symmetry structure.

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In this work a new donor of nitric oxide (NO) with antibacterial properties, namely nitrosyl iron complex of [Fe(CHC-SNH)(NO)][Fe(CHC-SNH)(SO)(NO)] composition (complex ), has been synthesized and studied. Complex was produced by the reduction of the aqueous solution of [Fe(SO)(NO)] dianion by the thiosulfate, with the further treatment of the mixture by the acidified alcohol solution of thiobenzamide. Based on the structural study of (X-ray analysis, quantum chemical calculations by NBO and QTAIM methods in the frame of DFT), the data were obtained on the presence of the NO…NO interactions, which stabilize the DNIC dimer in the solid phase.

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We use an x-ray free-electron laser to study the lattice dynamics following photoexcitation with ultrafast near-UV light (wavelength 266 nm, 50 fs pulse duration) of the incipient ferroelectric potassium tantalate, KTaO_{3}. By probing the lattice dynamics corresponding to multiple Brillouin zones through the x-ray diffuse scattering with pulses from the Linac Coherent Light Source (LCLS) (wavelength 1.3 Å and <10  fs pulse duration), we observe changes in the diffuse intensity associated with a hardening of the transverse acoustic phonon branches along Γ to X and Γ to M.

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