19 research outputs found

    The Effect of Certified Teachers and Principal Leadership toward Teachersā€™ Performance

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    This study aimed at determining the influence certified teachers and principal leadership either partially or simultaneously toward teachersā€™ performance in primary school Palembang. The research was conducted in several public primary schools in Gadus, Palembang. The research methodĀ  was ex post facto with 125 certified teachers while the sample wer 56 respondents. The data were collected by using questionnaires and analyzed by using t-test and F-test. The results of this study concluded that there is significant influence of certified teachers and principal leadership either partially or simultaneously toword teachersā€™ performance of primary school in Palembang

    Surgical treatment of secondary postuveal glaucoma by microinvasive non-penetrating deep sclerectomy with Healaflow implant injection: clinical case

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    The study aim was to evaluate the effectiveness of treatment of postveal uncompensated glaucoma in a patient with chronic infectious uveitis by microinvasive non-penetrating deep sclerectomy using drainage implant Healaflow. Material and methods. In a patient with the history of chronic uveitis, for the purpose of surgical treatment of secondary uncompensated post-uveal glaucoma, a microinvasive non-penetrating deep sclerectomy with the introduction of Healaflow has been performed in order to stabilize intraocular pressure, visual acuity and visual field. Healaflow was used to prevent proliferation and scarring in the early postoperative period. Results. At the follow-up period of 6 months after the operation, the drainage outflow tracts were preserved; intraocular pressure was stabilized. Conclusions. Microinvasive non-penetrating sclerectomy with Healaflow injection is the safe and effective method of surgical treatment of patients with postveal uncompensated glaucoma. The use of Healaflow is an effective method for preventing scarring of formed drainage outflow tracts

    The willingness of teachers to use modern educational technologies in educational process

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    Among the most significant trends in the development of vocational education, introduction and use of educational technologies can be distinguished. Since the main goal of higher schools is to prepare a competent competitive specialist, they search for the most suitable methods that contribute to rapid achievement of results. The use of technologies by educational institutions is explained by their advantage over other methods of developing professional competence. Due to implementation of a certain algorithm of actions, they allow you to achieve guaranteed results in a timely manner. The purpose of the article is to form future teachers ' the level of competency development, reflecting studentsā€™ willingness to adapt, adjust and use educational technologies in professional teaching activities. To do this, we checked the level of motivation of future teachers, the level of knowledge of the theoretical foundations of educational technologies, their design and implementation in professional and pedagogical activities, and the level of formation of the ability to reflect. The development of competencies reflecting the studentā€™s readiness to adapt, adjust and use educational technologies in professional pedagogical activity was carried out in a certain logical sequence, so that the student possessed versatile knowledge about educational technologies, was capable of their systematic creative application and his reflective activity was associated with self-actualization and striving for the implementation of constructive professional activities. The development process was carried out in the course of students solving research and design problems. Research activity was carried out by students in the study of the course ā€œPedagogical technologiesā€, fundamental for future teachers of vocational training. The implementation of the projects was carried out during the development of the course "Project Activities of a Professional Education Teacher"

    Soil Contamination Mapping with Hyperspectral Imagery: Pre- Dnieper Chemical Plant (Ukraine) Case Study

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    Radioactive contamination of soils is an issue of severe importance for Ukraine remaining with a significant post-Soviet baggage of not settled problems regarding radioactive waste. Regular radioecological observations and up-to-date contamination mapping based on advanced geoinformation techniques give an ability to prepare for, respond to, and manage potential adverse effects from pollution with radionuclides and heavy metals. Hyperspectral satellite imagery provides potentially powerful tool for soil contamination detection and mapping. An intention to find a relation between remotely sensed hyperspectral and ground-based measured soil contamination fractions in area of the uranium mill tailings deposits near Kamianske city was made. An advanced algorithm based on known TCMI (target-constrained minimal interference)-matched filter with a nonnegative constraint was applied to determine the soil contamination fractions by hyperspectral imagery. The time series maps of spatial distribution of the soil contamination fractions within study area around the Sukhachevske tailings dump are presented. Time series analysis of the map resulted in two independent parameters: the average value for the entire observation period and the daily mean increment of the soil contamination fractions

    Broadening the Action Spectrum of TiO<sub>2</sub>-Based Photocatalysts to Visible Region by Substituting Platinum with Copper

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    In this study, TiO2-based photocatalysts modified with Pt and Cu/CuOx were synthesized and studied in the photocatalytic reduction of CO2. The morphology and chemical states of synthesized photocatalysts were studied using UV-Vis diffuse reflectance spectroscopy, high-resolution transmission electron microscopy, and X-ray photoelectron spectroscopy. A series of light-emitting diodes (LEDs) with maximum intensity in the range of 365ā€“450 nm was used to determine the action spectrum of photocatalysts. It is shown for, the first time, that the pre-calcination of TiO2 at 700 Ā°C and the use of Cu/CuOx instead of Pt allow one to design a highly efficient photocatalyst for CO2 transformation shifting the working range to the visible light (425 nm). Cu/CuOx/TiO2 (calcined at 700 Ā°C) shows a rate of CH4 formation of 1.2 Ā± 0.1 Āµmol hāˆ’1 gāˆ’1 and an overall CO2 reduction rate of 11 Ā± 1 Āµmol hāˆ’1 gāˆ’1 (at 425 nm)

    Influence of Thermal Activation of Titania on Photoreactivity of Pt/TiO2 in Hydrogen Production

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    A series of Pt/TiO2 photocatalysts was prepared by impregnation of fresh and thermal-activated titania (commercial Evonik Aeroxide P25 TiO2) with an aqueous solution of H2PtCl6 followed by reduction in an aqueous solution of NaBH4. The thermal activation was performed by annealing in air. The photocatalytic activity of the Pt/TiO2 catalysts was measured for the hydrogen production from a mixture of glycerol under UV radiation. It was found that the activation at 300ā€“600 Ā°C provides an increase in the photoreactivity of resulting Pt/TiO2 photocatalysts in the production of hydrogen while its structural and textural properties do not change. This effect is due to formation of cationic vacancies that limits fast electronā€“hole recombination

    Copper-Modified Titania-Based Photocatalysts for the Efficient Hydrogen Production under UV and Visible Light from Aqueous Solutions of Glycerol

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    In this study, we have proposed titania-based photocatalysts modified with copper compounds for hydrogen evolution. Thermal pre-treatment of commercial TiO2 Degussa P25 (DTiO2) and Hombifine N (HTiO2) in the range from 600 to 800 &deg;C was carried out followed by the deposition of copper oxides (1&ndash;10 wt. % of Cu). The morphology and chemical state of synthesized photocatalysts were studied using X-ray diffraction, UV&ndash;Vis diffuse reflectance spectroscopy, high-resolution transmission electron microscopy, X-ray photoelectron spectroscopy, and XANES/EXAFS X-ray absorption spectroscopy. Photocatalytic activity was tested in the hydrogen evolution from aqueous solutions of glycerol under ultraviolet (&lambda; = 381 nm) and visible (&lambda; = 427 nm) light. The photocatalysts 2% CuOx/DTiO2 T750 and 5% CuOx/DTiO2 T700 showed the highest activity under UV irradiation (&lambda; = 380 nm), with the rate of H2 evolution at the level of 2.5 mmol (H2) g&minus;1 h&minus;1. Under the visible light irradiation (&lambda; = 427 nm), the highest activity of 0.6 mmol (H2) g&minus;1 h&minus;1 was achieved with the 5% CuOx/DTiO2 T700 photocatalyst. The activity of these photocatalysts is 50% higher than that of the platinized 1% Pt/DTiO2 sample. Thus, it was shown for the first time that a simple heat treatment of a commercial titanium dioxide in combination with a deposition of non-noble metal particles led to a significant increase in the activity of photocatalysts and made it possible to obtain materials that were active in hydrogen production under visible light irradiation

    Comparative Study of the Photocatalytic Hydrogen Evolution over Cd1āˆ’xMnxS and CdS-Ī²-Mn3O4-MnOOH Photocatalysts under Visible Light

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    A series of solid solutions of cadmium and manganese sulfides, Cd1āˆ’xMnxS (x = 0ā€“0.35), and composite photocatalysts, CdS-Ī²-Mn3O4-MnOOH, were synthesized by precipitation with sodium sulfide from soluble cadmium and manganese salts with further hydrothermal treatment at 120 Ā°C. The obtained photocatalysts were studied by the X-ray diffraction method (XRD), UV-vis diffuse reflectance spectroscopy, transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and N2 low temperature adsorption. The photocatalysts were tested in hydrogen production using a Na2S/Na2SO3 aqueous solution under visible light (Ī» = 450 nm). It was shown for the first time that both kinds of photocatalysts possess high activity in hydrogen evolution under visible light. The solid solution Cd0.65Mn0.35S has an enhanced photocatalytic activity due to its valence and conduction band position tuning, whereas the CdS-Ī²-Mn3O4-MnOOH (40ā€“60 at% Mn) samples were active due to ternary heterojunction formation. Further, the composite CdS-Ī²-Mn3O4-MnOOH photocatalyst had much higher stability in comparison to the Cd0.65Mn0.35S solid solution. The highest activity was 600 mmol gāˆ’1 hāˆ’1, and apparent quantum efficiency of 2.9% (Ī» = 450 nm) was possessed by the sample of CdS-Ī²-Mn3O4-MnOOH (40 at% Mn)

    Synthesis, Characterization and Photocatalytic Activity of Spherulite-like <i>r</i>-TiO<sub>2</sub> in Hydrogen Evolution Reaction and Methyl Violet Photodegradation

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    Synthesis and characterization of spherulite-like nanocrystalline titania with rutile structure (r-TiO2) are described herein. The r-TiO2 particles were synthesized via the convenient and low-cost hydrothermal treatment of TiO(C6H6O7) titanyl citrate. The r-TiO2 spherulites are micron-sized agglomerates of rod-shaped nanocrystals with characteristic sizes of 7(Ā±2) Ɨ 43(Ā±10) nm, oriented along (101) crystallographic direction, and separated by micropores, as revealed by SEM and TEM. PXRD and Raman spectroscopy confirmed the nanocrystalline nature of r-TiO2 crystallites. BET analysis showed a high specific surface area of 102.6 m2/g and a pore volume of 6.22 mm3/g. Photocatalytic performances of the r-TiO2 spherulites were investigated for the processes of methyl violet (MV) degradation in water and hydrogen evolution reaction (HER) in aqueous solutions of ethanol. The (MV) degradation kinetics was found to be first-order and the degradation rate coefficient is 2.38 Ɨ 10āˆ’2 mināˆ’1. The HER was performed using pure r-TiO2 spherulites and nanocomposite r-TiO2 spherulites with platinum deposited on the surface (r-TiO2/Pt). It was discovered that the r-TiO2/Pt nanocomposite has a 15-fold higher hydrogen evolution rate than pure r-TiO2; their rates are 161 and 11 nmol/min, respectively. Thus, the facile synthesis route and the high photocatalytic performances of the obtained nanomaterials make them promising for commercial use in such photocatalytic processes as organic contamination degradation and hydrogen evolution
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