53 research outputs found

    Permutable entire functions and multiply connected wandering domains

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    Let f and g be permutable transcendental entire functions. We use a recent analysis of the dynamical behaviour in multiply connected wandering domains to make progress on the long standing conjecture that the Julia sets of f and g are equal; in particular, we show that J(f)=J(g) provided that neither f nor g has a simply connected wandering domain in the fast escaping set

    Electrooxidation of Se on nanodispersed films of titanium dioxide modified with ZnO and Au

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    Selenium electrooxidation process on TiO2 and TiO2/ZnO electrodes, modified by gold nanoparticles, was investigated in solutions of sulfuric, chloric and citric acids. It is shown that TiO2/ZnO/Au electrodes can be used as indicator electrodes at the determination of selenium by anodic stripping voltammetry method. Optimum conditions of selenium (IV) determination are: supporting solution 0,001М H2SO4, electroconcentrating potential -(1,3¸1,5) V; time of electrolysis 120 s, scanning speed of potential 20 mV/s

    Pulsed Laser-Deposited TiO2-based Films: Synthesis, Electronic Structure and Photocatalytic Activity

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    Active under visible light, photocatalysts based on doped titania were obtained via pulsed laser deposition (PLD) method. To find out the crystalline structure, optical properties, and electronic structure, the following techniques such as X-ray diffraction, electronic spectroscopy, electrical conductivity measurements, and X-ray photoelectron spectroscopy (XPS) are used. Photocatalytic activity is monitored by applying the photoreduction of dichromate ions under UV and visible light. The influence of zirconium ions and its content and synthesis conditions on the efficiency of nitrogen incorporation into titania structure that, in turn, determines the electronic structure and photocatalytic ability of the semiconductive materials are discussed. A substitutional nitrogen (Ti–N) rather than an interstitial one (Ti–O–N) is mainly responsible for the observed photoactivity. It is pointed that substitutional nitrogen is responsible for bandgap narrowing or formation of intragap localized states within semiconductor bandgap. The bandgap energy values are sharply decreased, while the relative intensity of substitutional nitrogen XPS peaks is increased. Pulsed laser synthesis of TiO2 films in N2/CH4 atmosphere not only leads to nitrogen incorporation but also to the formation of defects including oxygen vacancies and Ti3+ states which are all contributing to light absorption. An appropriate ratio of gas mixture, optimum zirconia content, suitable pressure, and temperature during synthesis was found for the synthesis of highly active semiconductive films. The highest photocatalytic conversion yields are obtained for nitrogen-doped 10% ZrO2/TiO2 synthesized in N2:CH4 = 5:1 at 100 Pa and at 450°C under both UV and visible light

    Photoelectrochemical characterization and photocatalytic properties of mesoporous TiO

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    Optically transparent, crack-free mesoporous titania and zirconia-doped titania thin film photocatalysts were fabricated by sol-gel technique, using nonionic amphiphilic block copolymer Pluronic P123 as template. The structural and optical properties of these films were characterized using SEM, low-angle XRD, and UV/Vis spectroscopy, hexane adsorption investigation. Band gap energy and the position of flatband potentials were estimated by photoelectrochemical measurements. Enhancing of photocatalytic activity of zirconia-doped films relative to pure TiO2 originates from an anodic shift of the valence band edge potential. Catalytic activity of mesoporous TiO2 and TiO2/ZrO2 (5–50% of ZrO2) films in the processes of CrVI to CrIII photoreduction and 2,4-dinitroaniline photooxidation correlates with crystalline size and growth with increasing of specific surface area of the samples

    Beyaz

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    Taha Toros Arşivi, Dosya No: 3-Ziya Osman SabaUnutma İstanbul projesi İstanbul Kalkınma Ajansı'nın 2016 yılı "Yenilikçi ve Yaratıcı İstanbul Mali Destek Programı" kapsamında desteklenmiştir. Proje No: TR10/16/YNY/010

    A pilot study to determine the relationship of changes in the characteristics of β1- and β2-adrenoreceptors against the background of the use of β2-agonists with clinically significant parameters in patients with cardiovascular pathology

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    Background: Comorbid cardiovascular and bronchoobstructive diseases worsens disease course and prognosis and causes difficulties in therapy. Effectiveness 2-agonists (cornerstone of bronchoobstructive pathology treatment) depends on -adrenoreceptors state. Therefore, a detailed study of the functional state of beta-adrenoreceptors is necessary. Aim: to evaluate the relationship of changes in the characteristics of 1- and 2-adrenoreceptors, against the background of the use of 2-agonists in patients with cardiovascular and bronchoobstructive diseases with clinically significant parameters. Methods: In the pilot single-center prospective study during 2.5 years 45 patients (15 with cardiovascular and 30 with bronchoobstructive diseases) were included. Anamnestic data and complaints were collected and laboratory and instrumental studies were performed. Modified radioligand analysis on blood T-lymphocytes using radiolabeled Cyanopindolol and unlabeled selective ligands (ICI 118551, CGP 20712) before and after salbutamol and formoterol was performed and the binding activity of 1- and 2-adrenoreceptors was determined. Results: The correlation analysis between clinically significant parameters and changes in the specific binding index of 1- and 2-adrenoreceptors confirmed its clinical relevance. In test with beta-agonists in cardiovascular and bronchoobstructive diseases patients, an increase in the specific binding index of 1-adrenoreceptors is associated with clinical, laboratory and instrumental parameters of a favorable course of the disease, and an increase in the specific binding index of 2-adrenoreceptors is associated with negative. In the cardiovascular group without bronchoobstructive diseases with salbutamol an increase in the specific binding index of 1-adrenoreceptors was associated with parameters of unfavorable disease course, while an increase in the specific binding index of 2-adrenoreceptors did not have a clear associative relationship with clinical characteristics. Conclusions: The association of changes in the specific binding index of 1- and 2-adrenoreceptors in patients with cardiovascular and bronchoobstructive diseases with clinically significant parameters during acute tests with short- and long-acting 2-agonists was revealed, which in the future may provide an opportunity to identify patients with an unfavorable course of the disease
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