111 research outputs found

    Structure, optical, electrical and thermoelectric properties of solution-processed Li-doped NiO films grown by SILAR

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    The article presents a new facial synthesis of Li-doped NiO films (NiO:Li) via an easy and cost-effective method Successive Ionic Layer Adsorption and Reaction (SILAR) with the processing of the obtained NiO films in a lithium-containing aqueous solution for their transformation after annealing into NiO:Li layers. Comparative analysis of crystal structure, optical, electrical and thermoelectric properties of the obtained NiO and NiO:Li 420-1050 nm thick films have reveiled a cubic rock-salt NiO structure, at that, NiO:Li samples are nanocrystalline single phased Li-NiO solid solutions. The fabricated NiO and NiO:Li films are p-type semiconductors with activation energy Ea = 0.1 eV and Ea = 0.25‒0.31 eV, respectively. The obtained in-plane Seebeck coefficients Z are in the range 0.20–0.33 mV/К. Notwithstanding the fact that the maximum values of the thermoelectric power factors P=2.2 μW/K2·m, are rather small, they were achieved if the hot end of the NiO:Li film was heated only to 115 °C. Thus, the produced in this work new low cost thermoelectric thin film material is suitable for a production of electrical energy for low-power devices due to absorption of low-potential heat

    Advantages of cluster approach in managing the economy of the Russian Federation

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    The formation of new approaches to economic growth that will unite scientific, educational and production potentials, as well as lead to an increase in the competitiveness of enterprises, the region, the economy of the nation in general, both research and educational organizations, will have a further multiplier effect on the formation of an economy processes of a new order. This trend in the formation of modern approaches, and their successful implementation will result in the transition of the Russian economy to an economy of innovative type, more adjusted to relevant world trends and markets. The urgency of implementing cluster approaches in the development of the economy on the basis of innovative territorial clusters is dictated by the need to ensure a balanced and sustainable development of the domestic economic system through the promotion of innovation in individual territories. Such actively formed territories can now become clusters. In the modern world, clusters, with their completely different policy of realizing their activities, displaying the newest forms and competitiveness, become springboards' that help launch territories into the economy of the future. Today, the competitiveness of the economy of the region and the state depends not only on technical achievements or inventions, but also on organizational changes that contribute to the achievement by them of high commercial results, as well as on marketing innovations in the promotion and implementation of cluster policies

    Preparation Of ZnS Thin Films by the Chemical Bath Deposition Method

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    The work was financially supported by program 211 of the Government of the Russian Federation (№ 02.A03.21.0006)

    The Period Changes of the Cepheid RT Aurigae

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    Observations of the light curve for the 3.7-day Cepheid RT Aur both before and since 1980 indicate that the variable is undergoing an overall period increase, amounting to +0.082 +-0.012 s/yr, rather than a period decrease, as implied by all observations prior to 1980. Superposed on the star's O-C variations is a sinusoidal trend that cannot be attributed to random fluctuations in pulsation period. Rather, it appears to arise from light travel time effects in a binary system. The derived orbital period for the system is P = 26,429 +-89 days (72.36 +-0.24 years). The inferred orbital parameters from the O-C residuals differ from those indicated by existing radial velocity data. The latter imply the most reasonable results, namely a1 sin i = 9.09 (+-1.81) x 10^8 km and a minimum secondary mass of M2 = 1.15 +-0.25 Msun. Continued monitoring of the brightness and radial velocity changes in the Cepheid are necessary to confirm the long-term trend and to provide data for a proper spectroscopic solution to the orbit.Comment: Accepted for publication in PASP (November 2007

    ЭЛЕКТРООСАЖДЕННЫЕ ПЛЕНОЧНЫЕ КОМПОЗИЦИИ ДЛЯ ПРЕКУРСОРОВ КЕСТЕРИТНЫХ СОЛНЕЧНЫХ ЭЛЕМЕНТОВ

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    A comparative analysis of structure andsurface morphology of copper, tin, zinc films andfilm stacks madeby electrochemicaldepositionin galvanostaticsteady-state conditions, in galvanostatic modewith ultrasonicagitationof electrolytes,in the forwardpulse andreversepulse modeswith a rectangularpulses has been shown.The influence of themodesof electrodepositionon the structure, optical properties and surface morphology of theamorphous and crystalline selenium films presented.By sequentialelectrochemical deposition the film stacks Cu/Zn/Sn/Se andCu/Sn/Zn/Se were obtained, which are models ofkesterite precursors.Theseprecursorsafter theirconversion intoCu2ZnSnSe4 semiconductorsbysubsequent annealingwill be used asbase layers ofcheap and efficientthin film solar cellsof the new generation.Bibliography.10, Tab. 4, Fig.4.Представлены результаты сравнительного анализа структуры и морфологии поверхности пленок меди, олова, цинка и их слоевых композиций, изготовленных путем электрохимического осаждения в гальваностатическом стационарном режиме, в гальваностатическом режиме с ультразвуковым перемешиванием электролитов, в прямом импульсном и реверсивном импульсном режимах с прямоугольной формой импульсов потенциала. Изучено влияние режимов электроосаждения на структуру, оптические свойства и морфологию поверхности аморфных и кристаллических пленок селена. Путем последовательного электрохимического осаждения изготовлены пленочные композиции Cu/Zn/Sn/Se и Cu/Sn/Zn/Se, являющиеся моделями прекурсоров кестерита. Такие прекурсоры после их преобразования путем последующих отжигов в полупроводниковый материалCu2ZnSnSe4 будут использованы в качестве базовых слоев дешевых и эффективных тонкопленочных солнечных элементов нового поколения. Библ. 10, табл. 4, рис. 4.Представлены результаты сравнительного анализа структуры и морфологии поверхности пленок меди, олова, цинка и их слоевых композиций, изготовленных путем электрохимического осаждения в гальваностатическом стационарном режиме, в гальваностатическом режиме с ультразвуковым перемешиванием электролитов, в прямом импульсном и реверсивном импульсном режимах с прямоугольной формой импульсов потенциала. Изучено влияние режимов электроосаждения на структуру, оптические свойства и морфологию поверхности аморфных и кристаллических пленок селена. Путем последовательного электрохимического осаждения изготовлены пленочные композиции Cu/Zn/Sn/Se и Cu/Sn/Zn/Se, являющиеся моделями прекурсоров кестерита. Такие прекурсоры после их преобразования путем последующих отжигов в полупроводниковый материалCu2ZnSnSe4 будут использованы в качестве базовых слоев дешевых и эффективных тонкопленочных солнечных элементов нового поколения. Библ. 10, табл. 4, рис. 4

    Promising anticancer activity of batumin : a natural polyene antibiotic produced by Pseudomonas batumici

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    AIM : To determine the computer-predicted anticancer activity of antibiotic batumin. MATERIALS AND METHODS : Cytotoxicity assays, cell morphology microscopy and cell cycle progression were studied in cancer and nontumorigenic cell lines. An in vivo experiment on Lewis lung carcinoma (3LL)-transplanted mice was conducted to evaluate potential antimetastatic. RESULTS AND CONCLUSION : Cytotoxicity against melanoma and lung carcinoma cells (IC50 ≈ 5 μg/ml) was detected. Hypercondensed chromatin and apoptotic body formation in batumin-treated cells suggested the induction of apoptosis supported also by an observed increase in the quantity of cells occupying the sub-G1 cell cycle phase. Twofold reduction in the number and volume of lung metastases in Lewis lung carcinoma (3LL)-bearing batumin-treated mice was demonstrated. Highly specific cytotoxicity of batumin against cancer cell lines potentiates further studies.https://www.future-science.com/loi/fmc2019-09-01hj2018BiochemistryGeneticsMicrobiology and Plant PathologyPhysiologyPlant Production and Soil Scienc

    Boron isotopes in foraminifera : systematics, biomineralisation, and CO2 reconstruction

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    Funding: Fellowship from University of St Andrews, $100 (pending) from Richard Zeebe, UK NERC grants NE/N003861/1 and NE/N011716/1.The boron isotope composition of foraminifera provides a powerful tracer for CO2 change over geological time. This proxy is based on the equilibrium of boron and its isotopes in seawater, which is a function of pH. However while the chemical principles underlying this proxy are well understood, its reliability has previously been questioned, due to the difficulty of boron isotope (δ11B) analysis on foraminferal samples and questions regarding calibrations between δ11B and pH. This chapter reviews the current state of the δ11B-pH proxy in foraminfera, including the pioneering studies that established this proxy’s potential, and the recent work that has improved understanding of boron isotope systematics in foraminifera and applied this tracer to the geological record. The theoretical background of the δ11B-pH proxy is introduced, including an accurate formulation of the boron isotope mass balance equations. Sample preparation and analysis procedures are then reviewed, with discussion of sample cleaning, the potential influence of diagenesis, and the strengths and weaknesses of boron purification by column chromatography versus microsublimation, and analysis by NTIMS versus MC-ICPMS. The systematics of boron isotopes in foraminifera are discussed in detail, including results from benthic and planktic taxa, and models of boron incorporation, fractionation, and biomineralisation. Benthic taxa from the deep ocean have δ11B within error of borate ion at seawater pH. This is most easily explained by simple incorporation of borate ion at the pH of seawater. Planktic foraminifera have δ11B close to borate ion, but with minor offsets. These may be driven by physiological influences on the foraminiferal microenvironment; a novel explanation is also suggested for the reduced δ11B-pH sensitivities observed in culture, based on variable calcification rates. Biomineralisation influences on boron isotopes are then explored, addressing the apparently contradictory observations that foraminifera manipulate pH during chamber formation yet their δ11B appears to record the pH of ambient seawater. Potential solutions include the influences of magnesium-removal and carbon concentration, and the possibility that pH elevation is most pronounced during initial chamber formation under favourable environmental conditions. The steps required to reconstruct pH and pCO2 from δ11B are then reviewed, including the influence of seawater chemistry on boron equilibrium, the evolution of seawater δ11B, and the influence of second carbonate system parameters on δ11B-based reconstructions of pCO2. Applications of foraminiferal δ11B to the geological record are highlighted, including studies that trace CO2 storage and release during recent ice ages, and reconstructions of pCO2 over the Cenozoic. Relevant computer codes and data associated with this article are made available online.Publisher PDFPeer reviewe

    Changing atmospheric CO2 concentration was the primary driver of early Cenozoic climate

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    The Early Eocene Climate Optimum (EECO, which occurred about 51 to 53 million years ago)1, was the warmest interval of the past 65 million years, with mean annual surface air temperature over ten degrees Celsius warmer than during the pre-industrial period2–4. Subsequent global cooling in the middle and late Eocene epoch, especially at high latitudes, eventually led to continental ice sheet development in Antarctica in the early Oligocene epoch (about 33.6 million years ago). However, existing estimates place atmospheric carbon dioxide (CO2) levels during the Eocene at 500–3,000 parts per million5–7, and in the absence of tighter constraints carbon–climate interactions over this interval remain uncertain. Here we use recent analytical and methodological developments8–11 to generate a new high-fidelity record of CO2 concentrations using the boron isotope (δ11Β) composition of well preserved planktonic foraminifera from the Tanzania Drilling Project, revising previous estimates6. Although species-level uncertainties make absolute values difficult to constrain, CO2 concentrations during the EECO were around 1,400 parts per million. The relative decline in CO2 concentration through the Eocene is more robustly constrained at about fifty per cent, with a further decline into the Oligocene12. Provided the latitudinal dependency of sea surface temperature change for a given climate forcing in the Eocene was similar to that of the late Quaternary period13, this CO2 decline was sufficient to drive the well documented high- and low-latitude cooling that occurred through the Eocene14. Once the change in global temperature between the pre-industrial period and the Eocene caused by the action of all known slow feedbacks (apart from those associated with the carbon cycle) is removed2–4, both the EECO and the late Eocene exhibit an equilibrium climate sensitivity relative to the pre-industrial period of 2.1 to 4.6 degrees Celsius per CO2 doubling (66 per cent confidence), which is similar to the canonical range (1.5 to 4.5 degrees Celsius15), indicating that a large fraction of the warmth of the early Eocene greenhouse was driven by increased CO2 concentrations, and that climate sensitivity was relatively constant throughout this period

    навчальний посібник

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    Законодавче забезпечення правоохоронної діяльності : навч. посіб. / за заг. ред. В. В. Сокуренка. – Харків : Стильна типографія, 2017. – 1164 с. – (до 100-річчя підготовки охоронців правопорядку у Харкові).У навчальному посібнику представлено методичні рекомендації, пропозиції і зауваження до проектів нормативно-правових актів та наукові роз’яснення окремих положень чинного законодавства, розроблені кафедрами факультету № 1 Харківського національного університету внутрішніх справ. Наукові праці, що включено до навчального посібника, безпосередньо стосуються питань удосконалення форм та методів діяльності слідчих і інших підрозділів органів Національної поліції України. Для працівників органів Національної поліції України, науковців, викладачів, ад’юнктів, аспірантів, докторантів, курсантів, студентів та слухачів навчальних закладів юридичного профілю, а також усіх, хто цікавиться питаннями удосконалення діяльності органів Національної поліції України і інших органів правопорядку.The training manual presents methodological recommendations, suggestions and comments on draft normative legal acts and scientific explanations of certain provisions of the current legislation developed by the departments of the faculty No. 1 of the Kharkov National University of Internal Affairs. Scientific works, included in the textbook, directly relate to issues of improving the forms and methods of activity of investigative and other units of the National Police of Ukraine. For employees of the National Police of Ukraine, scientists, teachers, adjuncts, graduate students, doctoral students, cadets, students and students of legal educational institutions, as well as anyone interested in improving the activities of the National Police of Ukraine and other law enforcement agencies.В учебном пособии представлены методические рекомендации, предложения и замечания к проектам нормативно-правовых актов и научные разъяснения отдельных положений действующего законодательства, разработанные кафедрами факультета № 1 Харьковского национального университета внутренних дел. Научные труды, включен в учебного пособия, непосредственно касаются вопросов совершенствования форм и методов деятельности следственных и других подразделений органов Национальной полиции Украины. Для работников органов Национальной полиции Украины, научных работников, преподавателей, адъюнктов, аспирантов, докторантов, курсантов, студентов и слушателей учебных заведений юридического профиля, а также всех, кто интересуется вопросами совершенствования деятельности органов Национальной полиции Украины и других органов правопорядка
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