Resource-Efficient Technologies http://ojs.tpu.ru/index.php/res-eff <p><em>Resource-Efficient Technologies</em> is an international journal that publishes research and review articles, short communications, commentaries, and book reviews in the ever broadening field of sustainable and resource-efficient technologies, which reduce energy and materials consumption, reduce or completely eliminate toxic waste, develop closed-loop recycling technologies with the purpose of sustainable, economically efficient and socially responsible use of all natural resources and man-made product.</p> <p><em>Publisher</em>: Tomsk Polytechnic University<br>30,&nbsp;Lenin Avenue,&nbsp;Tomsk,&nbsp;&nbsp;634050,&nbsp;Russia<br>Tomsk Polytechnic University, Publishing House</p> Tomsk Polytechnic University en-US Resource-Efficient Technologies 2405-6537 INFLUENCE OF MOLECULAR AND CRYSTAL STRUCTURE ON NONLINEAR OPTICAL PROPERTIES OF HYDRATED AND ANHYDROUS POTASSIUM L-2-NITRIMINO-1,3-DIAZEPANE-4-CARBOXYLATE CRYSTALS http://ojs.tpu.ru/index.php/res-eff/article/view/220 <p>The physical properties of crystals depend on their chemical composition and their molecular and crystal structure. The presence of donor amino groups (NH<sub>2</sub>) and acceptor nitro groups (NO<sub>2</sub>) in a molecule can increase the molecule’s non–linear optical (NLO) properties. <em>L</em>-nitroarginine, in a strong alkaline environment (MOH (M=Li,Na,K), crystallizes to form <em>L</em>-2-nitrimino-1,3-diazepane-4-carboxylic acid (<em>L</em>-NIDCA⋅H<sub>2</sub>O and <em>L</em>-NIDCA). We found that the slow evaporation of a solution of <em>L</em>-nitroarganine and an alkali in equimolar<br>quantities leads to the formation of a metallic salt with <em>L</em>-2-nitrimino-1,3-diazepane-4-carboxylate anions<br>(K(<em>L</em>-NIDC)⋅H<sub>2</sub>O, Na(-NIDC), <em>L</em>-NaNIDC, Li(<em>L</em>-NIDC); this salt shows strong NLO properties. This study also addressed the second-harmonic generation of <em>L</em>-KNIDC⋅H<sub>2</sub>O and <em>L</em>-KNIDC crystals and how their crystal and molecular structure affects the NLO properties. The infrared and Raman spectra of K(<em>L</em>-NIDC)⋅H<sub>2</sub>O and K(<em>L</em>-NIDC) crystals were studied with respect to these structural features. We found that the intensity of second-harmonic generation in K(<em>L</em>-NIDC) is 2.75 times higher than in the standard KDP crystal, while the intensity in K(<em>L</em>-NIDC)⋅H<sub>2</sub>O is much lower.</p> R.A. Apreyan A.K. Atanesyan A.M. Petrosyan Copyright (c) 2019 Resource-Efficient Technologies https://creativecommons.org/licenses/by-nc/4.0 2019-03-29 2019-03-29 1 1 7 10.18799/24056537/2019/1/220 EXERGY OF A HYBRID SOLAR-WIND REVERSE OSMOSIS-MSF DESALINATION SYSTEM http://ojs.tpu.ru/index.php/res-eff/article/view/227 <p><span style="vertical-align: inherit;"><span style="vertical-align: inherit;"><span style="vertical-align: inherit;"><span style="vertical-align: inherit;">A novel hybrid solar-wind reverse-osmosis (RO) multistage flash (MSF) distillation desalination system was manufactured and tested in actual conditions in Iran. Solar energy was used to provide both thermal and electrical power and wind energy was used to provide electrical power. Exergy analysis can be used to design more efficient energy systems by reducing inefficien-cies, and indicates opportunities for improving performance in existing systems. The exergy involved in the hybrid solar-wind RO-MSF desalination system is analyzed below using data obtained from theoretical and experimental studies. The RO and MSF systems, powered by wind and solar energy, achieved increases in the reliability and flexibility of the system and in the quality of the resulting drinking water. According to the exergy analysis, the irreversible losses from the hybrid solar-wind RO-MSF plant are concentrated in the solar collector and the multistage flash chamber. These exergy losses can be reduced by isolating the collector, coating the pipes and MSF walls, selecting the parameters for the vapor compressor and RO membrane and pumps, and improving the flash process. By optimizing the performance of the hybrid solar-wind RO-MSF system, the amount of water recovery should increase, and the energy consumption should decrease, which should improve the overall efficiency of the system.<br></span></span></span></span></p> B. Heidary T. Tavakoli Hashjin B. Ghobadian R. Roshandel Copyright (c) 2019 Resource-Efficient Technologies http://creativecommons.org/licenses/by-nc/4.0 2019-04-25 2019-04-25 1 8 19 10.18799/24056537/2019/1/227 THE USE OF INCORRECTLY POSED INVERSE PROBLEMS AND CATASTROPHE THEORY IN ACOUSTOPLASMIC STUDIES http://ojs.tpu.ru/index.php/res-eff/article/view/228 <p>If the discharge current into a plasma contains direct and variable components, the plasma develops wavelike acoustic instabilities and eventually becomes an acoustoplasmа. Such instabilities lead to bistability, multistability, and hysteresis phenomena of the current–voltage characteristics, causing abrupt changes in the state of the plasma medium. These changes can be imagined as phase transitions and described using catastrophe theory. In the present study, the experimental plasma data are approximated by the equations of catastrophes. After reducing the catastrophe equation to canonical form, the points of possible phase transitions are determined. The phase transition coordinates are then converted to coordinates in the experimental system by inverse transformations. In this way, we determine the points of possible phase transitions in a real experiment. Finally, the parameter changes in an acoustoplasma discharge are obtained by solving incorrectly posed inverse problems. The inverse problem of the experimental data is solved at each current time. Within the neighborhoods of singular points, the incorrectly posed inverse problems are solved by the theory of catastrophes. The proposed methods are applicable to various fields of science and technology.</p> A.R. Mkrtchyan A.S. Abrahamyan R.Yu. Chilingaryan A.S. Mikayelyan Q.G. Sahakyan Copyright (c) 2019 Resource-Efficient Technologies http://creativecommons.org/licenses/by-nc/4.0 2019-04-25 2019-04-25 1 20 26 10.18799/24056537/2019/1/228 CONTROL OF CO2 LASER POWER BY ACOUSTIC FIELDS http://ojs.tpu.ru/index.php/res-eff/article/view/229 <p>The present study investigates the optimization of the operation of the CO<sub>2</sub> laser in the acoustoplasma mode (i.e., dependence of the laser radiation power on the composition of the working mixture, pressure, value of the direct component of the discharge current, frequency, and modulation depth).&nbsp;A three-dimensional dependence on the frequency and modulation depth of the discharge current is experimentally obtained for the normalized efficiency of the conversion of the electric power supplied to the discharge tube into laser power.&nbsp;The maximum gain when transition to the acoustoplasma mode exceeds 2.5 times. The optimum depth of the discharge current modulation is 0.5–0.7.&nbsp;The laser radiation power modulation caused by the discharge current modulation is measured. Laser power is not modulated at modulation frequencies of current &gt;1 kHz. Meanwhile, at current modulation frequencies &lt;0.5 kHz, the modulation depth of the laser radiation power nonlinearly depends on the modulation depth of the discharge current and has a threshold character.&nbsp;The modulation depth of the laser radiation power is associated with the creation of an acoustoplasma and not simply with the discharge current modulation.</p> A.S. Abrahamyan R.Yu. Chilingaryan Copyright (c) 2019 Resource-Efficient Technologies http://creativecommons.org/licenses/by-nc/4.0 2019-04-29 2019-04-29 1 27 34 10.18799/24056537/2019/1/229