The arrays of ZnO nanorods were obtained on the sapphire substrates by means of pulsed laser deposition under the high pressure of argon. The conditions of synthesis were optimized, and their influence on the morphology of ZnO nanostructures were revealed. It is shown that the concentration of oxygen vacancies in ZnO nanorods can be changed by regulation of the synthesis temperature from 850 to 915 °. This process can be controlled by the ratio of intensities of the photoluminescence emission in the visible and ultraviolet regions. So, it allows to create nanostructures for UV photodetectors or chemosensors depending on the temperature choice.
Keywords: ZnO nanorods, laser deposition, PLD, photoluminescence
In this paper a systematic study of individual single-walled and multi-walled carbon nanotubes was performed by Raman spectroscopy and high-resolution electron microscopy. We have presented the geometrical and electronic structure analysis on the examples of two tubes: individual single-walled and double-walled nanotubes. The role of different environmental effects and their influence on the final structure assignment are discussed. Moreover, we have shown that the Raman spectroscopy gives reliable estimations of the nanotube diameters and the conductivity. Given a non-destructible character of Raman spectroscopy, we may conclude that it is one of the most efficient methods for structure analysis of carbon nanotubes.
Keywords: Carbon nanotubes, Raman spectroscopy, electron microscopy
Article represents the analysis of activity of management companies in the market of housing-and-municipal services of Rostov-on-Don for definition of structure of the market and development of offers on its improvement on the basis of mechanisms of management, such as standards of housing and communal services, the public-private partnership, coordination of interests of business, administration and owners of housing stock.
Keywords: Management company, housing-and-municipal services, housing and communal services, public-private partnership.
An analysis of new methods and means for a mesurement of parameters of piezoelectric ceramic elements and materials is carried out. These methods and means are based on a digital principle of the construction of devices. An impuls with a linear frequncy modulation therein is used as an signal for exciting. Results of experimental studies on this subject are represented for discussion.
Keywords: piezo ceramic element, piezo, methods and means of measurement, digital signal processing
Intracellular microinjection - a method of direct introduction of cellular organelles and solutions of substances into living cells. The technique of microinjection into nerve cells by puncturing their processes - axons , which are often surrounded by a dense glial sheath, are described. To puncture the sheath a special injector transmitting microvibrations of ultrasonic frequency on the injection capillary was designed. The results of using the proposed microinjection technique for introducing fluorescent marker in large axons of model object - crayfish ventral nerve cord, to visualize the morphology of axons, were shown.
Keywords: intracellular microinjection, neuron, axon, glial sheath, ultrasound vibration, piezoelectric transducer
The authors suggest two approaches to constructing hypotheses about the interactions of proteins on the basis of the results of tracking the changes in their levels during the studied biological process. The first approach is based on the use of machine mining of biological texts, which are freely available on the Internet. The second is related to the execution of database queries on binary protein-protein interactions . To specify the experimental context in obtained protein networks, filtering of the protein entities on the basis of needed ontology from database Gene Ontology was used.
Keywords: text mining, data base, protein-protein interaction, protein networks
In the introduction the relevance of the study of diffusion along grain boundaries in metals. The aim of the work was to develop a method for determining the diffusion coefficient of impurity atoms at the grain boundaries in metals based on the numerical solution of the model by Fisher. The methodology laid plotting the ratio of the depth of bulk diffusion and grain boundary diffusion on the ratio of the diffusion coefficients of impurity atoms in them. In the construction of numerical solutions available to simplify the modeling of the physical nature of the process of diffusion along grain boundaries. The technique may be used in experiments with widely varying parameters diffusion annealing. Examples of the application procedure. The estimation of the coefficient of grain-boundary diffusion of copper in polycrystalline nickel. Also calculated the ratio of maximal depth of diffusion of silver in the grain and the grain boundary in the SMC copper.
Keywords: diversification of management, production diversification, financial and economic purposes of a diversification, technological purposes of ensuring flexibility of production
The return coefficient task of determination of properties of a construction design by means of the device of neural networks is considered. As model the neural network in the form of a polutorasloyny predictor with possibility of iterative accumulation of volume is taken. Each subsequent step connected with addition of a new stream of neurons, is carried out only after training of the previous stream. Coefficients of synoptic communications pay off with the help of procedure of the return distribution from a condition of a minimum of function of an assessment. Algorithms of the solution of direct and return problems of multidimensional approximation are developed.
Keywords: neural network, approximation, synoptic communications, return distribution, construction designs
In city system of environmental monitoring works on collecting data on production wastes and consumption of the enterprises of Taganrog are performed. The system includes three sections: quantity and types of a waste; data on places of long storage of a waste; data on the enterprises and technologies of processing of a waste. The scheme of management, maintaining and processing of base of ecological data is provided. Types of the analysis of collected data are considered.
Keywords: Production wastes and consumption, monitoring of a waste, municipal control system of a waste, scheme of management of a database
High purity ultrafine aluminum nitride is produced by gas-phase approach, however there is an issue to divide AlF3 and AlN at the final step of synthesis. Recently, the problem is solved by sublimation of aluminum trifluoride in vacuum, but due to high temperatures aluminum nitride particles agglomerate into chunks with dimension about 8 μm, hence the new alternate methods of separation is in a great interest. Flotation in organic environment is considered to divide aluminum trifluoride and aluminum nitride. The process of AlN and AlF3 interaction with organic and element-organic matters was investigated and the following conclusions were made: there is agglomeration and sedimentation stability of AlN and AlF3 in organic environments and flotation possibility was experimentally proved, hence, flotation after special treatment is a possible approach to divide powders of aluminum trifluoride and nitride.
Keywords: aluminum trifluoride, aluminum nitride, gas-phase synthesis, aglomeration, sedimentation, sublimation
The paper discusses possible options for the use of genre classification results of Web documents in search engines. The proposed methods can improve the quality of search engines.
Keywords: Web document classification, text documents, search engines, search engine results page, search quality, diversity
Structure of surface acoustic waves(SAW) of CO sensor was developed. SAW sensor include transceiving IDT and catoptric IDT, which is loaded on the impedance of ZnO nanorods. Peak of reflection SAW from IDT clearly observed as result Fourier transformation of time function of pulsed response. IDT loaded on resistance paralleled ZnO nanorods, which depends on the concentration of CO.
Keywords: ZnO nanorods, device on SAW, CO sensor
Combined method which allows analyzing parameters of the nanoscale atomic and electronic structure of materials relying on three different methods (x-ray absorption spectroscopy (XAFS), x-ray diffraction (XRD) and Raman spectroscopy) was developed. The method was applied for the study of nickel oxide nanoparticles, which serve as an efficient catalyst for the artificial photosynthesis process.
Keywords: solar energy, artificial photosynthesis, NiO, Raman, x-ray diffraction, XAFS
`
Keywords:
In the present work we have carried out studies of the processes of growth of zinc oxide nanorods by hydrothermal method on silicon substrates. As sublayer catalyst used growth caused by laser deposition of zinc oxide, various thicknesses. Studied selective growth of nanorods on the microstructure of thin-film sub-layers of zinc oxide obtained by laser deposition. The optimal conditions for the synthesis of: the concentration of Zn (NO3) 2 - 0.4 mol / l, hexamethylenetetramine - 0.4 mol / l, the concentration of NH3 · H2O - 0,01 mol / L -0.01, process time 4:00, the process temperature is 80 ° C. Sublayer thickness of zinc oxide, as shown by experiment, the growth of the rods has no noticeable effect. Oriented arrays of nanorods were obtained up to 500 nm and a diameter of 60-150 nm.
Keywords: zinc oxide nanorods and micro-oriented arrays of nanorods, hydrothermal synthesis method, selective growth, thin film underlayer.
Keywords: