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Исследовано влияние температуры осаждения на морфологию и структурно-фазовый состав подложечного материала на основе ZnO толщиной свыше 50 мкм при магнетронном распылении горячей керамической мишени. Показано принципиальное влияние температуры осаждения на скорость роста, морфологию и структурные параметры монокристаллического осадка ZnO. Продемонстрированы сверхвысокие (до 1.5 мкм/мин) скорости осаждения ZnO в режиме распыления горячей керамической мишени. Предложена методика формирования как гладкого, так и микропористого подложечного материала на основе ZnO без использования шаблонных технологий. Полученные в работе результаты могут найти широкое применение в оптоэлектронике и нитридных технологиях.

Введение в полимерную матрицу дисперсных веществ органической или неорганической природы осуществляется с целью улучшения физико-химических, механических, термических, электрических, трибологических свойств. В настоящее время возрастает интерес к композициям, обладающим бактерицидными, огнестойкими, теплопроводящими, антифрикционными свойствами. Одним из перспективных направлений является разработка многофункциональных композиций, обеспечивающих одновременно повышение нескольких важных эксплуатационных характеристик при сохранении физико-механических свойств. Использование соединений металлов в полимерных матрицах может приводить к значительному повышению всех описанных характеристик. Целью данной работы является анализ влияния нанооксидов металлов на свойства полимерных материалов. Наночастицы оксидов металлов имеют большие поверхностные заряды, которые связывают поверхность с полярными полимерами посредством электростатических взаимодействий. Они могут формировать одинарные связи металл – кислород с функциональными гидроксильными и карбоксильными группами в полимере, одинарные координационные связи металл – азот с функциональными группами на основе азота или водородные связи, таким образом оказывая влияние на весь комплекс свойств полимера. Наночастицы благодаря своим размерам могут выступать в роли зародышей кристаллообразования, таким образом влияя на количество образующихся кристаллов и их размер, а кристаллическое строение полимеров непосредственно связано с прочностью, т. е. способностью противостоять разрушению под действием нагрузки. Использование нанодобавок позволяет придать материалам антибактериальные свойства, а именно эффективную антибактериальную активность как против грамположительных, так и против грамотрицательных бактерий, повысить устойчивость композиций к горению и придать им фотокаталитическую активность

Waste solutions from the electrolytic production of copper contain significant amounts of copper and nickel sulfates, sulfuric acid, arsenic and other components of the copper electrolyte. The processing of such solutions is considered in this work not only from the point of view of environmental protection, but also in terms of extracting various valuable components from the electrolyte into commercial products. A thermodynamic analysis of the interactions between barium and arsenic, as well as their compounds in the Ba(AsO2)2-Ba3(AsO4)2-H2O system was carried out based on the E-pH diagram. The possibility of using barium compounds as a precipitant for arsenic from copper electrorefining solutions has been demonstrated. The efficiency of removing arsenic (more than 84%) from the electrolyte using barium oxide in the form of sparingly soluble barium arsenate has been established. By adding calculated amounts of zinc oxide into the working solution, it is possible to form solutions containing certain concentrations of Cu, Ni, and Zn. By further adding zinc oxide into the solution, its deep dehydration was achieved. The resulting copper-nickel-zinc and nickel-zinc solutions are the raw material for producing non-ferrous metal alloys using the electromembrane method. [ABSTRACT FROM AUTHOR]

Nanostructured semiconductor ZnO and ZnO-GO samples were synthesized at room temperature by chemical bath deposition technique. In this work, the electrochemical non-enzymatic determination of ascorbic acid was studied using the grown nanostructures deposited on a glassy carbon electrode. The morphology and structural properties of the synthesized nanostructured materials were analyzed using a scanning electron microscope and an X-ray diffractometer. The electrochemical properties were studied by the methods of cyclic voltammetry using a single-channel potentiostat-galvanostat. The sensitivity of the obtained electrodes was calculated based on concentrations of ascorbic acid in phosphate buffer solution from 0.3 mM to 3 mM at various scanning speeds. Thus, it was found that the sensitivity of the ZnO-GO sample is lower than that of the ZnO sample, which may be due to the dielectric properties of graphene oxide. However, after annealing in the atmosphere, the sensitivity of the ZnO-GO sample increased, which is associated with a decrease in defects in the sample and an increase in the specific surface area of the samples. As a result of the research, a modified ZnO-GO/GCE electrode with a high sensitivity of 386 μAM-1cm-2 was created, which is promising for use as the basis of a biosensor for determining the level of vitamin C in blood, food, and drugs. [ABSTRACT FROM AUTHOR]

The reaction of ethanol conversion to acetone on binary cerium-zinc oxide catalysts has been studied. It has been established that the reaction products of the conversion of ethyl alcohol on binary cerium-zinc oxide catalysts are ethylene, acetaldehyde, acetone, carbon dioxide and, at high temperatures, destructive decomposition products. The highest yield of acetone is observed on samples rich in zinc at temperatures of the order of 450-550°C, while catalysts rich in cerium are active in the reaction of dehydration of ethanol to ethylene. In this work, the acid properties of cerium-zinc oxide catalysts were evaluated by their activity in the isomerization of butene-1 to trans and cis butenes-2. It was found that cerium-rich catalysts are active in butene-1 isomerization reaction. The activities of cerium-zinc oxide catalysts in the reactions of the conversion of ethanol to acetone and the isomerization of butene-1 into trans and cis butenes-2 are compared. It was found that the reaction of the conversion of ethanol to acetone proceeds on the centers of the basic nature, and the formation of ethylene proceeds on the centers of the acidic nature. [ABSTRACT FROM AUTHOR]

The paper presents results of the synthesis of zinc oxide nanoparticles. The study of nanoparticles with the help of XRD showed that the samples have a wurtzite structure with an average crystallite size of 17 nm. The average hudrodynamic radius of the particles, studied with the help of Photocor Complex, was 70 nm. The images obtained with the scanning electron microscope make it possible to state polymorphous nano-sized agglomerates of zinc oxide nanoparticles were synthesized.

The template method has been employed to produce ZnO-based photon-crystal structures. There has been a study conducted investigating the impact of the temperature of developing opal-like crystals on their structural features

Введение. Наночастицы металлов могут обладать уникальными свойствами, отличающимися от свойств цельного металла, из которого они получены. Именно это обуславливает повышенный интерес к ним со стороны исследователей всего мира. Цель исследования. Количественная оценка антибактериального действия наночастиц серебра и оксида цинка на полиантибиотикорезистентные штаммы грамположительных и грамотрицательных микроорганизмов. Материал и методы. Выполнен синтез наночастиц серебра и оксида цинка методом лазерной абляции в жидкости. Изучены физические свойства и размеры данных наночастиц на основе спектральных характеристик и атомно-силовой микроскопии. Произведены изучение антибактериальной резистентности исследуемых микроорганизмов, а также количественная оценка антибактериального действия полученных наночастиц на основании определения минимальной ингибирующей и минимальной бактерицидной концентраций. Результаты. Все используемые в исследовании микроорганизмы являлись клиническими патогенными штаммами, обладающими полиантибактериальной резистентностью. При этом минимальные ингибирующие концентрации наночастиц серебра составили от 7,81 до 31,25 мкг/мл, а минимальные бактерицидные – от 31,25 до 62,50 мкг/мл, в то время как для наночастиц оксида цинка значения минимальных ингибирующих концентраций находились в пределах от 125 до 500 мкг/мл, а значения минимальных бактерицидных – от 250 до 1000 мкг/мл. Выводы. Метод лазерной абляции в жидкости позволяет синтезировать химически чистые наночастицы серебра, оксида цинка, а при необходимости и других металлов. Наночастицы серебра и оксида цинка являются эффективными противомикробными агентами по отношению к полиантибиотикорезистентной патогенной микробной флоре. Полученные значения минимальных бактерицидных и минимальных ингибирующих концентраций необходимо учитывать при последующем клиническом внедрении медицинских изделий на основе использования наночастиц металлов.

Copyright of Eurasian Physical Technical Journal is the property of E.A. Buketov Karaganda University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Diabetes mellitus, associated with insulin deficiency and high blood glucose, is one of the leading causes of death and disability in the world. Continuous monitoring of blood glucose levels can help prevent heart disease, kidney failure, or blindness. In this regard, fast, pricese and economical identification of blood glucose levels is necessary. Therefore, the manufacture of an economical, easy-to-use, exact, portable and fast glucose biosensor is of critical importance in diabetes mellitus. Electrochemical biosensors for glucose identification are widely used. In this work, arrays of highly oriented ZnO nanorods synthesized by a low-cost method of chemical deposition from solution was used as an amperometric enzymatic electrode in which glucose oxidase (GOx) was immobilized by physical adsorption. The morphology, optical and electrochemical properties of the fabricated modified ITO/ZnO/GOx/Nafion electrode were studied. The influence of the morphology of zinc oxide layers on the activity of the enzyme and biosensor was investigated. The resulting modified ITO/ZnO/GOx/Nafion electrodes with arrays of ordered thin ZnO nanorods showed a high sensitivity of ~50 μA/mM·cm2 for the detection of glucose in solution, i.e. ZnO nanorods with a high specific surface area are an excellent platform for the immobilization of glucose oxidase in biosensors. [ABSTRACT FROM AUTHOR]

В статье представлена характеристика методов получения оксида цинка. Рассмотрены методы химического осаждения, золь-гель, осаждения из газовой фазы, магнетронное нанесение, а также приведена сравнительная характеристика. Выполнены расчеты равновесия в системе «раствор – осадок». Проведено осадительное потенциометрическое титрование солей цинка с несколькими осадителями. Построенные кривые в координатах соотношение концентраций осадитель/катион – рН были использованы для определения оптимальных соотношений реагентов.

The rapid increase in population and the rapid development of industry has led to the formation of industrial effluents and pollution of water bodies with production waste harmful to their inhabitants and human health. In this regard, the task of cleaning water resources from industrial emissions, such as pesticides, organic dyes, heavy metals and other wastes, is relevant. Among transition metal oxides, zinc oxide (ZnO) is the most promising wide-gap semiconductor material, which, due to its unique properties, is actively used in various wastewater treatment methods. In this work, we studied the photocatalytic activity of nanostructured zinc oxide samples synthesized by an environmentally friendly, low-cost simple method of thermal decomposition of zinc acetate dihydrate with respect to the wide-spectrum insecticide Bi-58 New, the main active component of which is the organophosphorus compound dimethoate. Optical spectroscopy and photoluminescence were used to study an aqueous solution of Bi-58 New subjected to ultraviolet radiation in the presence of zinc oxide samples. Analytical separation was carried out by high performance liquid chromatography. An analysis of the obtained results showed the effectiveness of the application of nanostructured zinc oxide samples for the photocatalytic decomposition of insecticide Bi-58 New. [ABSTRACT FROM AUTHOR]

Results of hydrothermal deposition of undoped and Al doped ZnO nanocrystals on a single-crystal silicon wafers with a hydrogen passivated surface are presented. Hydrothermal deposition of undoped ZnO nanocrystals were carried-out in a equimolar solutions containing zinc nitride Zn(NO3)2 and hexamethylenetetramine C6H12N4. Aluminum nitride Al(NO3)3 were used as Al precursor during deposition of Al doped ZnO nanocrystals. The difference of the morphology of doped and undoped ZnO nanocrystals was shown. Photoluminescence properties of the doped and undoped ZnO nanocrystals were also studied.

Monocrystalline ZnO plane have been implanted by high dose (1,5·1017 cm-2) ions of manganese, iron, cobalt, nickel with energy of 40 keV at ion current density of 4 mA/cm2 in order to modified magnetic properties. Magnetic hysteresis loops at T = 5 K, temperature dependence of magnetization at sample cooling without and in magnetic field 2 mT in the temperature range 5-300 K were investigated. The main magnetic characteristics such as coercive force, magnetization saturation and residual magnetization have been estimated. It has been also shown, that implantation of cobalt and nickel ions leads to ensemble of Langeven magnetic nanoparticles formation in zinc oxide.

The processes of magnetron synthesis of ZnO–SnO2-based films by the magnetron sputtering of metal (Zn–Sn), ceramic (ZnO–SnO2) and composite (ZnO–SnO2 + 10wt.% Zn–Sn) targets were studied. It is shown that during magnetron sputtering of the metal and composite targets a multy-layered structure can be formed due to periodic changes in the composition of the sputtered target surface in the erosion zone. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Nano- & Electronic Physics is the property of Sumy State University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Nano- & Electronic Physics is the property of Sumy State University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A method for obtaining zinc oxide nanocomposite on the surface of graphene flakes was developed. The resulting nanocomposites were characterized by a complex of research methods: transmission electron microscopy, X-ray phase analysis, and photoluminescence spectra.

Copyright of Journal of Nano- & Electronic Physics is the property of Sumy State University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Metallophysics & Advanced Technologies / Metallofizika i Novejsie Tehnologii is the property of G.V. Kurdyumov Institute for Metal Physics, N.A.S.U and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Nano- & Electronic Physics is the property of Sumy State University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Nano- & Electronic Physics is the property of Sumy State University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Nano- & Electronic Physics is the property of Sumy State University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)