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The review of the use of process water in open pit mines and Russia and abroad helps find out that the conventional drainage technologies are inefficient for watercut lignite fields in the Kansk– Achinsk Basin. The author proposes a mining technology without preliminary drainage of watercut lignite seams, which ensures reduction in unproductive expenditures connected with coal mining and mitigation of the environmental impact.

In the modern world, sequencing is an integral part of medicine, biology and other scientific fields. The Illimina / Solexa method is a new generation method and relates to methods of mass parallel sequencing. One of the features of using this method is the sequential pumping of various chemicals through the flow cell in which the reaction occurs. For uniformity and high quality of DNA sequencing, it is necessary that the amount of gas in liquids be minimized. Because many it can adversely affect both during chemical reactions and at the stage of recording reaction results. This article will examine the sequencing system using the Illumina\Solexa method using bubble sensors. An algorithm was developed that periodically receives information from bubble sensors in a microfluidic tube. The information received is processed and allows at certain stages to report deviations from the normal conditions for sequencing. The experimental results are presented.

The development of a new semiconductor element base is necessary to create a new generation of applications. At present time, the synthesis of high-quality hybrid nanostructures based on III-V quantum dots in the body of nanowires of a wide range of material systems is an urgent and important task. In work hybrid III-V nanostructures based on QDs in the body of NWs in GaP/GaAs and AlGaP/InGaP material systems were synthesized in on silicon substrates and their physical properties were investigated.

The influence of the growth time on the structural properties of InGaN nanowires grown on Si substrate by plasma-assisted molecular beam epitaxy are studied. Under appropriate other growth conditions, the growth for 2h leads to the formation of separated nanowires, whereas the growth for 2h 30min and 3h leads to the formation of nanostructures such as nano-umbrellas. The separated NWs exhibit a photoluminescence spectrum with maxima at about 590 nm, whereas the nano-umbrellas show two pronounced photoluminescence lines at 421 and 619 nm.

In modern optoelectronics, arrays or single nanowires (NWs) of III-N materials, in particular InGaN, separated from the original substrates are used to fabricate light-emitting diodes or single photon sources. This work describes a technology of separation super-dense arrays or arrays of partially-coalesced InGaN nanowires and single nanowires from a Si substrate by chemical etching in HF:HNO3 solution, which allows preserving the optical properties of the structure for further use.

The possibility of the controlled removal of GaN nanowires (NWs) from an SiOx inhibitor layer of patterned SiOx/Si substrates has been demonstrated. It has been found that the wet KOH etching preserves the selectively grown GaN NWs on Si surface, whereas the GaN NWs grown on inhibitor SiOx layer are removing. The effect is described by the difference in polarity between GaN NWs grown on a Si surface and NWs grown on a SiOx inhibitor layer.

The possibility of AlGaAs nanowires with GaAs quantum dots and InP nanowires with InAsP quantum dots growth by molecular-beam epitaxy on silicon substrates has been demonstrated. Results of GaAs quantum dots optical properties studies have shown that these objects are sources of single photons. In case of InP nanowires with InAsP quantum dots, the results we obtained indicate that nearly 100% of coherent nanowires can be formed with high optical quality of this system on a silicon surface. The presence of a band with maximum emission intensity near 1.3 μm makes it possible to consider the given system promising for further integration of optical elements on silicon platform with fiber-optic systems. Our work, therefore, opens new prospects for integration of direct bandgap semiconductors and singlephoton sources on silicon platform for various applications in the fields of silicon photonics and quantum information technology.

The kinetics of photoluminescence of CuInS2/ZnS quantum dots at room temperature has been studied. We show that the parameters of the photoluminescence band of our quantum dots, i.e. its position and FWHM, do not depend on the delay time after the excitation laser pulse. These may suggest the spectral diffusion of photoluminescence of CuInS2/ZnS quantum dots due to hole localization at different Cu sites.

Young's modulus of tapered mixed composition (zinc-blende with a high density of twins and wurtzite with a high density of stacking faults) gallium phosphide (GaP) nanowires (NWs) was investigated by atomic force microscopy. Experimental measurements were performed by obtaining bending profiles of as-grown inclined GaP NWs deformed by applying a constant force to a series of NW surface locations at various distances from the NW/substrate interface. Numerical modeling of experimental data on bending profiles was done by applying Euler-Bernoulli beam theory. Measurements of the nano-local stiffness at different distances from the NW/substrate interface revealed NWs with a non-ideal mechanical fixation at the NW/substrate interface. Analysis of the NWs with ideally fixed base resulted in experimentally measured Young's modulus of 155 +/- 20 GPa for ZB NWs, and 157 +/- 20 GPa for WZ NWs, respectively, which are in consistence with a theoretically predicted bulk value of 167 GPa. Thus, impacts of the crystal structure (WZ/ZB) and crystal defects on Young's modulus of GaP NWs were found to be negligible.

The introduction in Russia of the Euro-5 standard and the tightening of rules on emissions of harmful substances has resulted in an overdue improvement in the methods and algorithms of calculation and design of toxicity decreasing systems to enhance the functioning of devices of these systems. Despite widespread methods of simulation and computer modelling for the study and testing of the proposed organizational and technical measures, it is relevant to assess the increase of exhaust recirculation motor units with the help of experimental studies. The purpose of the study is to evaluate emissions of harmful substances of the car exhaust and suggest an experimental device based on the apparatus and methodology for analysis of carbonyl compounds and volatile organic compounds. In assessing of the effectiveness of reducing the toxicity, significant attention is paid to methods of experimental studies. As an indicator of the effectiveness in reducing the toxicity of motor units, the volume of emissions of harmful substances was selected. The choice of the components of the experimental system for the automated processing of the environmental inspection results of motor vehicles was substantiated. These components are: software tools that implement the conduction of the test by a cold start of the engine and chassis dynamometer settings, as well as monitoring the progress of the experiment; interactive systems to transmit information between the posts of ecological police, private persons and legal entities, companies for the maintenance of vehicles.

InGaN nanostructures are among the most promising candidates for visible solid-state lighting and renewable energy sources. To date, there is still a lack of information about the influence of the growth conditions on the physical properties of these nanostructures. Here, we extend the study of InGaN nanowires growth directly on Si substrates by plasma-assisted molecular beam epitaxy. The results of the study showed that under appropriate growth conditions a change in the growth temperature of just 10 °C leads to a significant change in the structural and optical properties of the nanowires. InGaN nanowires with the areas containing 4%–10% of In with increasing tendency towards the top are formed at the growth temperature of 665 °C, while at the growth temperatures range of 655 °C–660 °C the spontaneously core–shell NWs are typically presented. In the latter case, the In contents in the core and the shell are about an order of magnitude different (e.g. 35% and 4% for 655 °C, respectively). The photoluminescence study of the NWs demonstrates a shift in the spectra from blue to orange in accordance with an increase of In content. Based on these results, a novel approach to the monolithic growth of In x Ga1−x N NWs with multi-colour light emission on Si substrates by setting a temperature gradient over the substrate surface is proposed.

We present the results of selective-area growth of GaN nanowires by molecular beam epitaxy on patterned SiOx/Si substrates without using seed layers. The morphological and optical properties of selectively grown GaN nanowires are compared to the properties of GaN nanowires grown on the amorphous SiOx layer. The experimental results show that the selectivity of GaN nanowires is achieved at a substrate temperature of 825 °C which is the lower limit for the selective-area growth of GaN nanowires on SiOx/Si substrates. The study of the photoluminescence spectra of the grown nanowires, measured at 77 K show an emission line at 3.47 eV, which corresponds to strain-free GaN.

Carbon fiber reinforced polymers (CFRP) are widely used in the manufacturing of critical parts and structures in the aerospace industry due to the combination of low density, high strength, and stiffness. Production of parts and structures with pre-predicted properties is a difficult task provided significant anisotropy of physical properties and complex microstructure. The solution to this problem has to be based on the correct mathematical model describing the behavior of parts and structures made of CFRP under operational loads. Moreover, experimental data on physical, mechanical, and thermophysical properties and their change depending on the number of loading cycles has to be implemented. In view of the above, prediction of the occurrence and development of microcracks in the material becomes significant. The aim of this article is to develop algorithms for prediction and detection of primary microcracks in CFRP under loading using fiber Bragg grating (FBG) sensors and multiscale mathematical modeling. The results of measuring the primary residual deformations in the plates made of CFRP at the manufacturing stage by embedded FBG sensors and testing its performance under loading was presented. Multiscale mathematical modeling of a numerical experiment performed to evaluate the occurrence of areas of primary microcracks in CFRP under loads. It is demonstrated that splitting of peaks of resonant wavelengths of embedded FBG sensors indicates the occurrence of primary damage and microcracks.