Publications by authors named "Alexander Y Vul'"

According to the classical nucleation theory, the presence of solid particles in a liquid should facilitate its heterogeneous nucleation upon supercooling. Here, we have analysed the behaviour of aqueous dispersions of detonation diamond nanoparticles (DND) with different signs of the surface charge in supercooled conditions and the frozen state. The behaviours of the diamond nanoparticles with a typical size of 4.

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This paper submits experimental results of a study directed towards the formation of Eu ions' luminescent centers in CVD diamond films. A new approach is based on use of diamond nanoparticles with a surface modified with Eu ions for seeding at CVD growth. Nanocrystalline diamond films (NCD) doped with Eu have been grown from the gas phase on silicon substrates by microwave plasma-assisted CVD at a frequency of 2.

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Purpose: Testing the potential use of saline suspension of polyvinylpyrrolidone (PVP)-coated gadolinium(Gd)-grafted detonation nanodiamonds (DND) as a novel contrast agent in MRI.

Methods: Stable saline suspensions of highly purified de-agglomerated Gd-grafted DND particles coated by a PVP protective shell were prepared. T and T proton relaxivities of the suspensions with varying gadolinium concentration were measured at 8 Tesla.

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Objectives: Detonation nanodiamonds (DND) with Gd ions directly grafted to the DND surface have recently demonstrated enhanced relaxivity for protons in aqueous suspensions. Herewith, the relaxivity measurements were done on a series of suspensions with the gadolinium content varied by changing number of Gd ions grafted per each DND particle whereas the DND content in each suspension was kept the same. Such an approach to vary the contrast agent content differs from that commonly used in the relaxivity measurements.

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This paper reports a facile and green method for conversion of graphene oxide (GO) into graphene by low-temperature heating (80 °C) in the presence of a glass wafer. Compared to conventional GO chemical reduction methods, the presented approach is easy-scalable, operationally simple, and based on the use of a non-toxic recyclable deoxygenation agent. The efficiency of the proposed method is further expanded by the fact that it can be applied for reducing both GO suspensions and large-scale thin films formed on various substrates prior to the reduction process.

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Monodisperse carbon nanodots (MCNDs) having an identical composition, structure, shape and size possess identical chemical and physical properties, making them highly promising for various technical and medical applications. Herein, we report a facile and effective route to obtain monodisperse carbon nanodots 3.5 ± 0.

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We report on investigation of detonation nanodiamond annealed at 800C°in chlorine atmosphere by means of 1H, 13C and 35Cl nuclear magnetic resonance and X-ray photoelectron spectroscopy. The results of these methods are found to be consistent with each other and evidence formation of chlorine-carbon groups and sp2 carbon shell on the nanodiamond surface. The data obtained provide detailed information about the structure and bonding in this diamond nanoparticle.

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