A new approach of recognition of ellipsoidal micro- and nanoparticles on AFM images and determination of their sizes

© 2016 IOP Publishing Ltd.In this work we develop an approach of automatic recognition of ellipsoidal particles on the atomic force microscopy (AFM) image and determination of their size, which is based on image segmentation and the surface approximation by ellipsoids. In addition to the comparative simplicity and rapidity of processing, this method allows us to determine the size of particles, the surface of which is not completely visible on the image. The proposed method showed good results on simulated images including noisy ones. Using this algorithm the size distributions of silica particles on experimental AFM images have been determined

Development of Demulsifier Compositions for the Destruction of Emulsions and Dehydration of Heavy Oils

In oils, oil products and oil fractions, which do not contain paraffins, the action of depressors is useless. In this connection, the research of depressor properties of experimental samples of demulsifying compositions became possible only in regions where highly paraffinic oils are extracted, prepared and transported. Joint researches concerning the study of effect of the developed composite reagents on the rheology of heavy oil from Zhangurshi deposit of the West Kazakhstan region was carried out at al-Farabi Kazakh National University, Institute of Combustion Problems and the Kazan Scientific-Research Technological University. Conducting a comparative evaluation of the wetting power of a number of surfactants made it possible to obtain information on the efficiency of the inversion of wetting in oil-dispersed systems during the destruction of water-oil emulsions. In this work, the express methods for determining of wetting-deterging action of a wide range of different classes and types of surfactants are used, which makes it possible to make a comparative assessment of their effectiveness in a short time. During the research, it was supposed that the washing process of adsorption hydrocarbon layer, including tar-asphaltene substances, from the surface of particles of mechanical impurities involved in stabilization of water-oil emulsion should be preceded by a wetting process

3D polarization-controlled tip-enhanced Raman scattering spectroscopy and microscopy

В работе освещаются физические принципы 3 поляризационной спектроскопии гигантского комбинационного рассеяния света для визуализации и диагностики одиночных молекул и/или их групп [1,2]. Рассматривается механизм управления поляризацией оптического ближнего поля на субволновых масштабах с помощью оптических наноантенн [3-5]. Используя разработанный метод, определяется пространственная ориентация азобензольных хромофоров (Рис. 1) в полимерной матрице и детектируются углеродные наноструктуры в защитном слое оптических волокон.In this paper, we highlight physical principles of 3D polarization-controlled Tip-Enhanced Raman Scattering (TERS) spectroscopy and microscopy for single molecule detection [1,2]. In particular, we consider mechanisms for controlling the near-field polarization on the nanoscale using optical nanoantennas [3-5]. Spatial orientation of azo-dyes embedded into a glassy environment, as shown in Fig. 1, and carbon allotropes within protective claddings of optical fibers are probed with this technique

Experimental manifestations of the Nb^{4+}-O^{-} polaronic excitons in KTa_{0.988}Nb_{0.012}O_{3}

The formation of the photo-polaronic excitons in ABO_{3} perovskite type oxides has been detected experimentally by means of the photoinduced electron paramagnetic resonance studies of KTa_{0.998}Nb_{0.012}O_{3} crystals. The corresponding microwave X-band spectrum at T < 10 K consists of a narrow, nearly isotropic signal located at g ~ 2 and a strongly anisotropic component. The first signal, which has a rich structure due to hyperfine interactions with the lattice nuclei, is attributed to the single trapped charge carriers: the electrons and/or the holes. The anisotropic spectrum is caused by the axial centers oriented along the C_{4} pseudo-cubic principal crystalline axes. The spectrum angular dependence can be described well by an axial center with S = 1, g_{\parallel) = 0.82, g_{\perp} = 0.52 and D = 0.44 cm^{-1}. The anisotropic spectrum is attributed to the Nb^{4+}-O^{-} polaronic excitons. The temperature dependence of the anisotropic component is characterized by two activation energies: the internal dynamics activation E_{a1} = 3.7\pm0.5 meV, which makes the EPR spectrum unobservable above 10 K, and the destruction energy E_{a2} = 52\pm4 meV. By comparing the anisotropic photo-EPR spectrum and the photoinduced optical absorption temperature dependencies, we found that the Nb^{4+}-O^{-} polaronic excitons also manifested themselves via the ~0.7 eV wide absorption band arising under UV light excitation in the weakly concentrated KTaO_{3}:Nb crystals.Comment: PDF, 15 pages, 6 figures (submitted to Physical review B

A new approach of recognition of ellipsoidal micro- and nanoparticles on AFM images and determination of their sizes

© 2016 IOP Publishing Ltd.In this work we develop an approach of automatic recognition of ellipsoidal particles on the atomic force microscopy (AFM) image and determination of their size, which is based on image segmentation and the surface approximation by ellipsoids. In addition to the comparative simplicity and rapidity of processing, this method allows us to determine the size of particles, the surface of which is not completely visible on the image. The proposed method showed good results on simulated images including noisy ones. Using this algorithm the size distributions of silica particles on experimental AFM images have been determined

A new approach of recognition of ellipsoidal micro- and nanoparticles on AFM images and determination of their sizes

© 2016 IOP Publishing Ltd.In this work we develop an approach of automatic recognition of ellipsoidal particles on the atomic force microscopy (AFM) image and determination of their size, which is based on image segmentation and the surface approximation by ellipsoids. In addition to the comparative simplicity and rapidity of processing, this method allows us to determine the size of particles, the surface of which is not completely visible on the image. The proposed method showed good results on simulated images including noisy ones. Using this algorithm the size distributions of silica particles on experimental AFM images have been determined

A new approach of recognition of ellipsoidal micro- and nanoparticles on AFM images and determination of their sizes

© 2016 IOP Publishing Ltd.In this work we develop an approach of automatic recognition of ellipsoidal particles on the atomic force microscopy (AFM) image and determination of their size, which is based on image segmentation and the surface approximation by ellipsoids. In addition to the comparative simplicity and rapidity of processing, this method allows us to determine the size of particles, the surface of which is not completely visible on the image. The proposed method showed good results on simulated images including noisy ones. Using this algorithm the size distributions of silica particles on experimental AFM images have been determined

Quantum interference via nonradiative transitions between energy levels of atoms in one-dimensional photonic crystals

© Published under licence by IOP Publishing Ltd. The self-energy correction to the mass of an atomic electron placed into a void of the photonic crystal medium is investigated. In this study the one-dimensional photonic crystal made from gallium arsenide and vacuum layers is considered. We show that the electron mass change gives rise not only to the shifts of the atomic energies but also to the nonradiative transitions between atomic levels. These transitions add new channels to a decay of an atomic state that leads to a quantum interference between these channels