Publications by authors named "V I Shevelev"

We used x-ray photoemission and absorption spectroscopies to study the influence of thermal molecular oxygen exposure on the h-BN/Co(0001) and h-BN/Au/Co(0001) systems. The spectral analysis was supported by density functional theory calculations. It is shown that oxygen can intercalate h-BN on Co(0001) and also be embedded into its lattice, replacing the nitrogen atoms.

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Recrystallization of bulk materials is a well-known phenomenon, which is widely used in commercial manufacturing. However, for low-dimensional materials like graphene, this process still remains an unresolved puzzle. Thus, the understanding of the underlying mechanisms and the required conditions for recrystallization in low dimensions is essential for the elaboration of routes towards the inexpensive and reliable production of high-quality nanomaterials.

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Regardless of the widely accepted opinion that there is no Raman signal from single-layer graphene when it is strongly bonded to a metal surface, we present Raman spectra of a graphene monolayer on Ni(111) and Co(0001) substrates. The high binding energy of carbon to these surfaces allows formation of lattice-matched (1 × 1) structures where graphene is significantly stretched. This is reflected in a record-breaking shift of the Raman G band by more than 100 cm relative to the case of freestanding graphene.

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This study was designed to compare effectiveness and safety of warfarin, direct thrombin inhibitor dabigatran, Xa factor inhibitors rivaroxaban and apixaban used to prevent stroke in 280 elderly patients in patients with age-specific non-valvular atrial fibrillation. The treatment of patients aged 65-74 and 75-80 yearsfor 2 years with dab itragan (110 mg b.i.

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We compared efficacy and safety of warfarin with those of direct thrombin inhibitor dabigatran, factor Xa inhibitors rivaroxaban and apixaban used for stroke prevention in 280 patients aged 65-80 years with non-valvular atrial fibrillation. Treatment for two years with dabigatran (110 mg twice daily), apixaban (5 mg twice daily) or rivaroxaban (20 mg/day) prevented strokes no less successfully than warfarin, but more rarely caused severe intracranial hemorrhages. When selecting antithrombotic therapy in geriatric patients with non-valvular AF new oral anticoagulants may be regarded as an acceptable alternative to warfarin.

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