Nonlinear acousto-magneto-plasmonics

We review the recent progress in experimental and theoretical research of interactions between the acoustic, magnetic and plasmonic transients in hybrid metal-ferromagnet multilayer structures excited by ultrashort laser pulses. The main focus is on understanding the nonlinear aspects of the acoustic dynamics in materials as well as the peculiarities in the nonlinear optical and magneto-optical response. For example, the nonlinear optical detection is illustrated in details by probing the static magneto-optical second harmonic generation in gold-cobalt-silver trilayer structures in Kretschmann geometry. Furthermore, we show experimentally how the nonlinear reshaping of giant ultrashort acoustic pulses propagating in gold can be quantified by time-resolved plasmonic interferometry and how these ultrashort optical pulses dynamically modulate the optical nonlinearities. The effective medium approximation for the optical properties of hybrid multilayers facilitates the understanding of novel optical detection techniques. In the discussion we highlight recent works on the nonlinear magneto-elastic interactions, and strain-induced effects in semiconductor quantum dots.Comment: 30 pages, 12 figures, to be published as a Topical Review in the Journal of Optic

Using Air for Increasing the Depth of the Flue Gas Heat Recovery

The methods of flue gas heat recovery have been reviewed and carried out their effectiveness analysis. Revealed a theoretical limit of flue gas deep heat recovery and suggested possible ways to achieve them. The possibility of using air as a heated medium is discussed in more detail

Experimental study of heat transfer from the gas-vapor mixture to the surface in rectangular channel with the water vapor condensation

The laboratory setup was developed for studying the water vapor condensation process from the gas mixture on a vertical flat heat exchange surface in rectangular channel 10x2 cm. The experiments were carried out with normal pressure of steam-air mixture. The results allowed to determine the heat transfer coefficient from steam-gas mixture to the heat transfer surface. The dependences of the heat transfer coefficient on the initial moisture content and the mixture flow rate in the heat exchanger channel were obtained

Foraging in Boreal Forest: Wild Food Plants of the Republic of Karelia, NW Russia

While the current consumption of wild food plants in the taiga of the American continent is a relatively well-researched phenomenon, the European taiga area is heavily underrepresented in the scientific literature. The region is important due to its distinctive ecological conditions with restricted seasonal availability of wild plants. During an ethnobotanical field study conducted in 2018-2019, 73 people from ten settlements in the Republic of Karelia were interviewed. In addition, we conducted historical data analysis and ethnographical source analysis. The most widely consumed wild food plants are forest berries (three Vaccinium species, and Rubus chamaemorus), sap-yielding Betula and acidic Rumex. While throughout the lifetime of the interviewees the list of used plants did not change considerably, the ways in which they are processed and stored underwent several stages in function of centrally available goods, people's welfare, technical progress, and ideas about the harm and benefit of various products and technological processes. Differences in the food use of wild plants among different ethnic groups living in the region were on the individual level, while all groups exhibited high variability in the methods of preparation of most used berries. The sustainability of berry use over time has both ecological and economical factors.While the current consumption of wild food plants in the taiga of the American continent is a relatively well-researched phenomenon, the European taiga area is heavily underrepresented in the scientific literature. The region is important due to its distinctive ecological conditions with restricted seasonal availability of wild plants. During an ethnobotanical field study conducted in 2018-2019, 73 people from ten settlements in the Republic of Karelia were interviewed. In addition, we conducted historical data analysis and ethnographical source analysis. The most widely consumed wild food plants are forest berries (three Vaccinium species, and Rubus chamaemorus), sapyielding Betula and acidic Rumex. While throughout the lifetime of the interviewees the list of used plants did not change considerably, the ways in which they are processed and stored underwent several stages in function of centrally available goods, people s welfare, technical progress, and ideas about the harm and benefit of various products and technological processes. Differences in the food use of wild plants among different ethnic groups living in the region were on the individual level, while all groups exhibited high variability in the methods of preparation of most used berries. The sustainability of berry use over time has both ecological and economical factors

Research of efficiency of the organic Rankine cycle on a mathematical model

The object of the study are the organic Rankine cycle. The purpose of research is to evaluate the impact on the net efficiency of the initial and final properties of the cycle at work on a saturated and superheated steam. Investigations were carried out on the basis of a mathematical model, in which the thermodynamic properties of materials are determined on the basis of "REFPROP". On the basis of the available scientific publications on the use of working fluids in an organic Rankine cycle analysis was selected ozone-safe pentane. A mathematical model has been developed on condition that condenser is used as air cooler which allows the substance to condense at a temperature below 0 С. Numerical study on the mathematical model shown that net efficiency at work on pentane linearly depends on the condensation temperature and parabolically depends on the initial temperature with the saturated steam. During work at the superheated steam efficiency strongly depends on both the initial temperature and of the initial pressure. With rising initial temperature is necessary to gradually increase the initial pressure under certain conditions

Efficiency of utilization of heat of moisture from exhaust gases of heat HRSG of CCGT

The paper discusses the technology of utilizing the heat of exhaust gas moisture from heat recovery steam gases (HRSG) of combined-cycle gas turbine (CCGT). Particular attention focused on the influence of the excess air factor on the trapping of the moisture of the exhaust gases, as in the HRSG of the CCGT its value varies over a wider range than in the steam boilers of the TPP. For the research, has been developed a mathematical model that allows to determine the volumes of combustion products and the amount of water vapor produced according to a given composition of the burned gas and determine the amount of moisture that will be obtained as a result of condensation at a given temperature of the flue gases at the outlet of the condensation heat exchanger (CHE). To calculate the efficiency of the HRSG taking into account the heat of condensation of moisture in the CHE an equation is derived

Flue gas moisture capacity calculation at the outlet of the condensation heat recovery unit

As a result, study equation has been obtained which determine the flue gas moisture capacity at the outlet of the condensation heat recovery unit with an error of less than 1%. It possible to at the temperature of the flue gas below the dew point and the known air-fuel ratio efficient. The equation can be used to calculate plants operating on products of gas combustion without Use of tables and programs for calculating the water-vapor saturation pressure

G-Jitter, Vibrations, Diffusion: The IVIDIL Experiment

Experiments aboard the International Space Station (ISS) provide a large but still limited amount of data. A complete set of data is usually returned to Earth on a flash disk a few months later, by which time the experimental facility has already been put into storage or trashed. Thus, scientists have no possibility to repeat the experiment, even if some ambiguities are later found. Therefore, onboard experiments require careful preparation on the ground with multiple tests in the laboratory and in parabolic flights, if possible. Furthermore, during postflight analysis, it is important to clarify all unknown sources of errors. One of the most obvious sources of perturbations on the ISS is g-jitter. Here, we present the preparation and implementation of the Influence of Vibrations on Diffusion in Liquids (IVIDIL) experiment on the ISS, which studied the effect of random g-jitter and given vibrations on diffusion-controlled experiments in liquid mixtures. Since diffusion in liquids is a slow process, only vibrational effects were examined in parabolic flights. A methodology for the analysis of diffusion and thermodiffusion processes was developed in the laboratory

Luminescent probe method in the study of the interaction of glycated human serum albuminwith non-glycated human serum albumin

Background and Objectives: The development and functioning of all living beings ends with the inevitable aging process, as a result of which the activity of all organs and the body as a whole is suppressed, which leads to imminent death. Protein glycation is considered to be one of the causes of aging. This process takes place throughout life, but it intensifies with age. Protein glycation is a reaction of covalent coupling of free amino groups of proteins and reducing carbohydrates, which proceeds without the participation of enzymes and leads to disruption of protein functions. This process is unregulated, as it occurs without the participation of biological catalysts. As a result of glycation of proteins in humans, inflammatory processes occur in the body and a number of diseases such as heart attack, stroke, atherosclerosis, cataract, glycemia, Alzheimer’s disease, diabetes mellitus, etc. develop. In the tasks of medical diagnostics, methods of monitoring the state of proteins in the human body are necessary. In this regard, the work is devoted to the study of the processes of interaction of human serum albumin globules (HSA) with globules of human glycated serum albumin (gHSA). Materials and Methods: In conducting a study of the spectral-kinetic characteristics of the eosin luminescent probe in solutions of glycated and non-glycated HSA, as well as in a mixture of glycated and non–glycated HSA, an exponential dependence of the second order was used to approximate the dependencies of DF (delayed fluorescence) and PHOS (phosphorescence), and an anisotropy equation was used to assume the formation of the gHSA-HSA complex. Results: It has been found that the intensity and kinetics of quenching of delayed fluorescence and phosphorescence of the eosin fluorescent probe associated with proteins are sensitive to the ratio of glycated and non-glycated proteins in solution. To explain the increase in the intensity and lifetime of eosin phosphorescence during the transition from a solution of HSA to a mixture of HSA and gHSA, it is assumed that the globules of HSA and gHSA form a complex of the composition of gHSA-HSA, as a result of diffusion encounters. The rotational mobility of this complex is much less than the separate globules of HSA and gHSA. The formation of the complex is confirmed by an increase in the anisotropy of delayed fluorescence and phosphorescence of eosin in a mixture of HSA and gHSA. Conclusion: The obtained results of the work can be used to diagnose the presence of a complex of glycated with non-glycated proteins in human blood plasma.&nbsp

Promising Direction of Perfection of the Utilization Combine Cycle Gas Turbine Units

Issues of improving the efficiency of combined cycle gas turbines (CCGT) recovery type have been presented. Efficiency gas turbine plant reaches values of 45 % due to rise in temperature to a gas turbine to 1700 °C. Modern technologies for improving the cooling gas turbine components and reducing the excess air ratio leads to a further increase of the efficiency by 1-2 %. Based on research conducted at the Tomsk Polytechnic University, it shows that the CCGT efficiency can be increased by 2-3 % in the winter time due to the use of organic Rankine cycle, low-boiling substances, and air-cooled condensers (ACC). It is necessary to apply the waste heat recovery with condensation of water vapor from the flue gas, it will enhance the efficiency of the CCGT by 2-3 % to increase the efficiency of the heat recovery steam boiler (HRSB) to 10-12 %. Replacing electric pumps gas turbine engine (GTE) helps to reduce electricity consumption for auxiliary needs CCGT by 0.5-1.5 %. At the same time the heat of flue gas turbine engine may be useful used in HRSB, thus will increase the capacity and efficiency of the steam turbine