The paper describes the specific features of power supply to the off-grid consumers in the northern territory of the Republic of Sakha (Yakutia). Territorial zoning is made by the indices of total solar radiation received on horizontal surface and annual sunshine duration. Retrospective data on the solar power plants construction are presented for the offgrid area of the Republic which despite its northern location is a pioneer in this field of energy. The design differences of some power plants are described. This allows the experts of the local company to substantiate the priority solutions for the climatic conditions of the Republic based on the experimental data. A list of the populated settlements is presented with indication of the total capacity of solar power plants by area of the Republic. The paper demonstrates the dynamics of the total indices of electricity generation, the saving of diesel fuel and cost for its purchase in 2011–2016. Based on the analysis of solar power plant operation in the settlement of Dzhargalakh located beyond the Polar circle, we make a conclusion on the advantages of monocrystalline modules for the arctic conditions compared to the thin-film and polycrystalline ones. Actual data on electricity generation by month of the year are indicative of its typical pronounced summer maximum and virtual absence in winter. The paper shows the dynamics of electricity generation for a five-year period for each of the seven solar power plants constructed before 2015, and cost saving by fuel substitution at diesel power plants. Considerable changes in electricity generation are connected only with additional equipment to be placed into service. Increase in the cost saving is caused by growth of diesel fuel price. Actual data on the cost of the construction projects and cost saving are used to determine payback periods for seven solar power plants located in different areas of the Republic. Research has revealed that the latitudinal location does not affect payback periods of the projects while the diesel fuel price is the most decisive factor. In this context, even in the arctic areas of the Republic with winter polar night period, the payback period of the projects for construction of solar power plants is comparable with the power plants located in much more southerly areas and does not exceed 10 years.

The paper deals with the results of computational and experimental research to justify the safety of life tests of the lead test assemblies with low-enriched fuel. As a result of calculation studies conducted in the Institute of Nuclear Physics of the Republic of Kazakhstan, the eight-tube and five-tube fuel assemblies with thin-walled fuel elements (thickness 1.6 mm), later named FA VVRKN, have been chosen for conversion of the WWR-K research reactor to LEU fuel (19.7% for uranium-235). The new fuel assembly has a developed surface of heat removal which makes it possible to create on its basis a compact core without increasing in flow rate of coolant and to improve the experimental reactor capabilities. The paper presents the results of in-pile LTA test (three experimental LTA VVR-KN were manufactured at the Novosibirsk Chemical Concentrates Plant, Russia) to confirm the design characteristics and to verify the performance of new design of the fuel assemblies with low enriched uranium fuel. We have proven using calculations that the design characteristics of fuel assemblies can achieve in the core of the WWR -K reactor. The paper notes that the main difficulty of this research is the creation of the necessary test modes in the core of the WWR-K reactor because the power of the LTA is over two times higher than that of the regular fuel assembly of a reactor with highly enriched uranium fuel. We have determined that the life test of three LTA in the WWR-K reactor core requires a change in the configuration and composition of the core, and, consequently, the analysis of the test safety. The calculation results have shown that the thermo-technical safety of the WWR-K reactor core is provided during the performance of the three LTA life test.

The rejection of hydrogen as a solution to global warming by becoming the medium of wind and solar was made when gasoline was priced at $1/gallon. From wind, H2 would now cost (by electrolysis of water and steam) less than $3 for an amount equivalent in energy to that in a gallon of gasoline (“equivalent”). From solar photovoltaics (pv), H2 would be sinking in price between $8 toward $5 equivalent as the efficiency of solar pv increases toward 20%. Solar thermal’s present prices offer about one-half the solar pv prices. Prediction of the maximum of the delivery rate of world oil is [Laherre’s Oil Production Forecast, 1950–2150. Reprinted with permission from correspondence with William Horvath, U.S. Department of Energy, March 29, 2001] 2010. Future energy sources will develop inexhaustible energies from wind, solar, geothermal, tidal, and wave sources. The common media will be hydrogen and electricity. These sources yield energy at around one-half the cost of nuclear fission. Growing corn to make alcohol involves a net loss of energy and need for a heating mechanism. It may increase the Greenhouse.

In order to create an efficient fuel cell based on a high-temperature proton conductor, it is necessary to develop a long-lived proton electrolyte. In the general case, the long-term chemical stability of the phase to CO2 is provided by thermodynamics (impossibility of reaction) or interaction kinetics (slowing down of the reaction). The paper compares the chemical stability with respect to CO2 (both thermodynamic and related to kinetic difficulties) for promising high-temperature proton conductors based on double perovskite Ba4-xCa2+xNb2O11 (x = 0.4; 0 ; –0.4) and double fluorite La6-xWO12-1.5 (x = 0.4, 0.6, 0.8, 1). The temperature of resistance to CO2 (above which the phase is stable to CO2, below which the phase interacts with CO2) is an important technical characteristic of the thermodynamic stability of the phase to CO2. The upper limit of the operating temperatures of the solid oxide fuel cell is 1,000ºC. When the temperature of stability is the lower, then the phase is more stable to CO2. We use solid-phase synthesis, X-ray diffraction, thermogravimetry with mass spectrometry and conductivity measurement by the impedance method. It is established that materials based on La6WO12 are relatively thermodynamically stable in ordinary air with CO2 (10-3 bar) in the operating range of 650–1,000 ºC. The phases based on Ba4Ca2Nb2O11 are resistant to CO2 in the air in the range of 850–1,000 ºC. In order to use the material in conditions of its thermodynamic stability, the stability temperature is required to be below the operating temperature (400–700 ºC). Thus, phases based on Ba4Ca2Nb2O11 are thermodynamically unstable to CO2 at 700ºC, and phases based on La6WO12 are stable at 700ºC. In the absence of thermodynamic stability of the phase, stability of this phase to CO2, associated with the kinetic difficulties, may be revealed in some cases, which is sufficiently long-term for practical use. For example, it is possible to form a continuous diffusion-blocking surface layer of products of interaction with CO2 (Ba, Ca, La carbonates) at the grain boundary of the main phase. The increase in the grain-boundary resistance observed for the studied samples may indicate the formation of a surface layer of products of interaction with CO2. For ceramic samples La6-xWO12-1.5x (x = 0.4, 0.6, 0.8, 1), the grain-boundary and electrode resistance after aging for 30 days at 200ºC in moist atmospheric air (CO2 10-3 bar) is shown to increase approximately 3 times at 800ºC and 10 times at 400 ºC.

In order to improve the wear resistance of machine parts in industry and agriculture, the various synthetic lubricants with mesogenic additives are used. It is established that adding an additive to the base lubricant leads to a decrease in the friction coefficient and a decrease in the wear of the machine parts. Such multi-component systems, lubricants and additives, are lyotropic liquid crystals (LC) and exhibit rich mesomorphism which also affects their tribological characteristics. The composing of phase diagrams of LC lubricants with additives depending on the concentration and thermodynamic quantities is an important research task in connection with the need to optimize the composition of lubricants and to determine the regimes of their most effective employment. In this regard, in addition to mechanical testing of specimens in the presence of lubricant compositions, it is necessary to study the physicochemical properties and carry out structural studies of multicomponent lubricants. We were motivated by the possibility to complement the existing data on the optical and X-ray spectroscopy, electron microscopy and theoretical studies of the thermodynamic parameters of lubricant composites by dielectric spectroscopy (DE). Using the method of DE spectroscopy, we first investigated the electrical properties of lubricating compositions based on Litol’s-24 comprising mesogenic additives as homologues carboxylates of copper (II), valerate and isovalerate copper in the concentration range 1, 5, 10 and 20 wt. %. We found the frequency dependence of the dielectric permeability, conductance, dielectric loss, as well as the temperature and concentration dependence of the electrical quantities of lubricant compositions in the measuring electric field of the frequency range 100 Hz – 1 MHz and at heating from room temperature to temperatures exceeding Litol’s-24 melting temperature. The paper confirms the possibility of the occurrence of phase transitions between the columnar and isotropic liquid-crystalline phases at the concentrations of additives of 1, 5 and 10 wt. %, and estimates the activation energies of the lubricant compositions in order of magnitude. The obtained results are applicable for the analysis of tribological characteristics of lubricant compositions.

The paper deals with lithium which is currently characterized by one of the fastest growth rates in terms of price, consumption and production volumes. We have estimated the rates of consumption, the growth in production volumes and the growth of the explored volumes of lithium mineral resources and have given forecast of development of the world lithium market, growth of lithium production and price dynamics. Thus, the increase in world production of lithium by 2020 should exceed 12,000 tons per year. The increase in the consumption of lithium is shown to stimulate the growth of geological exploration of its mineral resources and to lead to a sharp increase in the explored lithium reserves. Moreover, we have attempted to evaluate other lithium mineral resources including those with a low content of lithium. The analysis demonstrate that, in accordance with existing technologies and speed of the lithium production growth, lithium ore will run out in about 25 years, and lithium reserves of proven resources associated with salt lakes will be depleted in about 50 years. The paper suggests several ways of solving this problem. The first one is an increase in the extraction of lithium from existing sources of raw materials, that is, the use of more effective methods. The second one is the use of lean lithium resources, such as underground brines and associated oil waters which can become the most promising source of lithium (the possible directions and prospects of extraction have been shown). The third way is the use of secondary lithium resources and the processing of spent lithium batteries. Keywords: lithium; lithium market; world reserves of lithium; lithium mining; underground brines; associated oil waters.

The widespread introduction of polymer composite materials in key sectors of modern industry such as wind and hydropower engineering, aircraft and machinery ones, etc. due to the high level of their strength properties, versatility and ability to provide the lowest weight of parts of products raises the problem of their processing. Traditional processing methods (mechanical and abrasive water jet machining) have some significant shortcomings: high tool wear, delamination due to vibration and shock loadings, limitations on the cutting contour and others. The paper deals with the polymer composites laser machining which is considered to be one of the promising solutions for elimination of conventional methods disadvantages due to a contact-free, flexible and high-performance processing method. As a result of analysis of theoretical and experimental domestic and foreign works, the use of industrial ytterbium fiber lasers are found to be a promising direction for high-quality and productive processing of polymer composite materials. The results of studies using the experimental technological setups on the basis of nanosecond pulsed and continuous ytterbium fiber lasers with a radiation power up to 1 kW and optical scanning systems based on the biaxial galvo scanners and focusing F-Theta lenses with beam travel speeds up to 20 m / s have shown that the laser multi-pass machining of polymer composite materials with layer-by-layer removal (ablation) of the material due to the evaporation mechanism allows for precise and high quality cutting and drilling of carbon and glass fiber reinforced plastics and carbon plastics with a thickness 1–3 mm.

The review gives the main points of the current state of holographic sensors development based both on researches of foreign scientists and on the results of the only group in Russia dealing with this problem. Holographic sensors are a new class of diagnostic devices that are thick-layered holograms recorded instead of gelatin in a special hydrogel that reacts to the presence of certain substances in liquid and gas mixtures. The cross-links of the hydrogel matrix are tuned to the test component of the mixture, and the more the hydrogel layer of the sensor shrinks or swells, the higher the component concentration is. This mechanism makes it possible to quantify the concentration of a particular substance. The paper describes the main properties, advantages, measuring capabilities, and possible applications of the holographic sensors. In this case, water quality studies are very promising, both in urban water supply systems and for monitoring ecosystems in natural reservoirs. Moreover, with the holographic sensors it is possible to measure the hardness and acidity of water, as well as pollution with ions of heavy metals, bacteria and their spores, etc. To monitor the atmosphere, there are specially designed holographic sensors that allow determining the content of combustible hydrocarbon gases in air, and air humidity and temperature. The sensors can also be widely used in medicine in order to determine the concentrations of a wide range of compounds contained in biological fluids. The review discusses in detail the problems that arise when analyzing the level of glucose in blood plasma and serum and draws the comparison of holographic sensors with existing diagnostic tools. We consider the possibilities of using digital imaging technology, including smartphones, as an alternative to spectrometric registration of the sensor response because, compared with spectrometers, widespread digital photographic equipment significantly simplifies the measurements and reduces their cost. This is very important for the operative monitoring of environmental parameters, especially in the field. The review details the problems of measuring the wavelength of the light reflected from the sensor for different types of data available in digital cameras (image formats). Based on the arguments available in the literature, the authors substantiate the importance of designing holographic sensors for the growing sector of the express diagnostic market in practical medicine.