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The aim of this study is to determine the effect of changes in the phase composition of Al2O3–Si3N4 ceramics that were obtained using the method of mechanochemical solid-phase grinding on their resistance to the process of long-term thermal exposure, accompanied by the processes of oxidation and softening. The relevance of this research consists of determining the influence of the phase composition of ceramics on the change in their strength and thermophysical parameters, on the basis of which, we can draw a conclusion about the optimal composition of composite ceramics that have great prospects in the field of fire-resistant, heat-resistant, or radiation-resistant structural materials. During this study, the dynamics of the changes in the phase transformations of the xAl2O3–(1−x)Si3N4 ceramics, with variations in the ratio of the components, initiated by the thermal annealing of the samples, was established. According to the assessment of the phase transformations with variations in the ratio of the components, it was found that thermal annealing in an air environment at an Al2O3 concentration in the order of 0.3–0.5 M leads to the formation of an orthorhombic Al2(SiO4)O phase and an elevation in its contribution at concentrations above 0.5 M, which causes a rise in the thermophysical parameters and resistance to high-temperature degradation. During the heat resistance tests, it was found that the formation of the composite ceramics with the Si3N4(SiO2)/Al2(SiO4)O/Al2O3 phase composition results in an increase in the stability of their strength properties when exposed to thermally induced oxidation, which has a negative impact on their resistance to softening and a decrease in hardness. Moreover, the presence of the Al2(SiO4)O phase in the composition of the ceramics causes a slowdown in the processes of thermal oxidation of the Si3N4 phase under prolonged temperature exposure, alongside an increase in the degradation resistance of strength properties by more than 4–7 times, in comparison with the softening data established for single-component ceramics. [ABSTRACT FROM AUTHOR]

The aim of this study is to determine the effect of changes in the phase composition of Al2O3–Si3N4 ceramics that were obtained using the method of mechanochemical solid-phase grinding on their resistance to the process of long-term thermal exposure, accompanied by the processes of oxidation and softening. The relevance of this research consists of determining the influence of the phase composition of ceramics on the change in their strength and thermophysical parameters, on the basis of which, we can draw a conclusion about the optimal composition of composite ceramics that have great prospects in the field of fire-resistant, heat-resistant, or radiation-resistant structural materials. During this study, the dynamics of the changes in the phase transformations of the xAl2O3–(1−x)Si3N4 ceramics, with variations in the ratio of the components, initiated by the thermal annealing of the samples, was established. According to the assessment of the phase transformations with variations in the ratio of the components, it was found that thermal annealing in an air environment at an Al2O3 concentration in the order of 0.3–0.5 M leads to the formation of an orthorhombic Al2(SiO4)O phase and an elevation in its contribution at concentrations above 0.5 M, which causes a rise in the thermophysical parameters and resistance to high-temperature degradation. During the heat resistance tests, it was found that the formation of the composite ceramics with the Si3N4(SiO2)/Al2(SiO4)O/Al2O3 phase composition results in an increase in the stability of their strength properties when exposed to thermally induced oxidation, which has a negative impact on their resistance to softening and a decrease in hardness. Moreover, the presence of the Al2(SiO4)O phase in the composition of the ceramics causes a slowdown in the processes of thermal oxidation of the Si3N4 phase under prolonged temperature exposure, alongside an increase in the degradation resistance of strength properties by more than 4–7 times, in comparison with the softening data established for single-component ceramics.

To justify the safety of dry storage, thermal tests of VVER-1000 fuel rods in electrically heated modules in a helium medium were carried out, realizing stationary conditions and a thermal cycling regime with different cycle times and a total test time of 427–468 days. The effect of thermal tests on the elongation of fuel rods that were used in VVER-1000 reactors for one year (fuel burnup of ~20 MW day/kg U) and for six years (burnup of ~70 MW day/kg U) was studied. Fuel rods with high fuel burnup elongated less than those with low burnup. The maximum values of elongation were registered for fuel rods with low burnup: 6.0 mm when tested under stationary conditions and 9.5 mm in the thermal cycling mode. Hoop strain of the fuel rods increased insignificantly. The presence of gas pressure under the cladding provides tensile stresses, creating conditions for the implementation of thermal creep. For fuel rods with lower fuel burnup, the gap between the fuel and the cladding was preserved along the entire height of the core (column). The main mechanism for elongation of fuel rods is the cladding thermal creep under the action of increased effective axial stresses arising from the internal fuel rod gas and the pressure of the fuel column on the spring plunger. Thermal cycling leads to a greater elongation of the fuel rods owing to a higher cladding creep rate at the unsteady-state stage in short cycles. [ABSTRACT FROM AUTHOR]

This study conducted a comprehensive experimental and numerical assessment to investigate the effect of plastic circular balls placed in the middle of a section of a reinforced concrete slab on strength, ductility, thermal, and acoustic performance. The ball diameter/slab thickness (D/H), grades of concrete, and longitudinal tensile reinforcement ratio (ρ) in the slab were selected as the main variables. The variation in thermal and acoustic performance depending upon the ball's diameter was investigated as well. The results showed that the slab's load-carrying capacity, ductility, and energy dissipation capacity did not differ if the D/H ratio did not exceed 0.4; however, significant decreases in these values were observed when the D/H ratio exceeded 0.4. Moreover, the increase in the concrete and reinforcement's strength had a negative effect on the slab with a D/H ratio of 0.8. The experimental results revealed that balled slabs are 3.15 times superior with respect to thermal conductivity and provide 1.38 times more insulation to absorb sound compared to non-balled slabs. In the numerical study of the slabs' thermal performance, the mean surface temperature and heat flux on the slab where the heat transfer takes place decreased as the ball diameter increased. As seen in acoustic models, the level at which the slabs absorbed sound varied depending upon both the diameter of the balls and the sound frequency. [ABSTRACT FROM AUTHOR]

This paper presents first studies carried out in the European project INCIT-EV, to design a solution for integrating a wireless inductive charging system for electric vehicles in a bituminous pavement. In the project, specific tests and simulations were developed to study the mechanical and thermal behaviour of this electric road. In particular, laboratory wheel tracking tests were used to study, at reduced scale, the mechanical behaviour of a charging coil integrated in the pavement. Charging tests were also performed to study the temperature variations produced by the heat dissipation in the inductive coils. Finally, finite element models have been used to simulate the thermal and mechanical response of the system in the pavement structure. The paper presents some main results of this study, which allowed to validate the mechanical behaviour of the proposed pavement structure, but also highlighted risks of overheating when the system is in operation, which will need further investigation.

This paper presents results of in-plane shear tests carried out at the ZAG laboratory in Ljubljana (Slovenia) on a RC frame with masonry infill made of clay blocks (KEBE OrthoBlock). The frame was loaded with constant vertical loads at the top of the columns and then by gradually increasing horizontal cyclic loads at the top beam level. Acquired forces and measured displacements allowed capturing hysteretic behavior for determination of dissipation energy. In addition, two Digital Image Correlation (DIC) systems, Aramis and the CivEng Vision, were used to visualize the behavior of the tested specimens, with an emphasis on computing locally required information about the behavior of highly deformable interfaces. Three types of specimens were tested in-plane: the reference specimen in form of plain RC frame, the reference specimen with constructed masonry infill without any strengthening and the specimen, previously damaged and then strengthened on both sides using glass mesh bonded to the infill and the RC frame using flexible adhesive made of polyurethane matrix (Glass Fiber Reinforced PolyUrethane - GFRPU system). The strengthening process, allowed the specimen to withstand additional cyclic loads, reaching a maximum drift of 3.6 % without serious damage disqualifying the structure from further exploitation. The GFRPU strengthening system was found to be highly effective in preventing infill collapse of damaged masonry infill wall during in-plane loading. Additionally, the results of extended thermal analysis of PU are presented as polymers are, in general, a material, poorly resistant to heat. However, the analyzed PU manifested stable properties up to 200 degrees Celsius, which makes this material promising in civil engineering applications at elevated temperatures. • In-plane push-over cyclic tests of RC frame strengthened by flexible GFRPU system. • Maximum frame drift of the value 3.6 %, without serious damage. • GFRPU strengthening system was very effective and resistant to out-of-plane forces. • FRPU matrices made of PU are resistant to elevated temperatures. • Local large deformations of GFRPU system identified by DIC measurements. [ABSTRACT FROM AUTHOR]

This article presents the experimental results of mechanical properties of fuel rod claddings from E110 zirconium alloy in the longitudinal direction that operated in fuel assemblies of VVER-1000 nuclear reactors to the fuel burnup of ~20 and ~70 MW d/kg U before and after post-radiation annealing at 380°C for 468 days. The changes in strength and plastic properties of the cladding in longitudinal direction were analyzed in comparison with its properties before and after irradiation and with their changes in the transverse direction. The changes in mechanical properties of the cladding are explained as a function of radiation damage of its structure. [ABSTRACT FROM AUTHOR]

This paper presents a test stand equipped, among others, with two boilers intended for the combustion of solid fuels. The first is a single-fuel boiler designed to burn wood pellets only. The second is a multi-fuel boiler intended for the combustion of mainly hard coal (basic fuel) with the grain size of 0.005-0.025 m. Wood pellets can also be fired in this boiler, which in such a case are treated as a substitute fuel. There is a developed and verified algorithm for the control of the multi-fuel boiler operation in a wide range of loads for the basic fuel. However, for the substitute fuel (wood pellets) there are no documented and confirmed results of such testing. The paper presents selected results of testing performed during the combustion of wood pellets in a multi-fuel automatically stoked boiler. Several measuring series were carried out, for which optimal operating conditions were indicated. These conditions may serve as the basis for the development of the boiler operation control algorithm. A detailed analysis was carried out of the flue gas temperatures obtained at the outlet of the boiler combustion chamber and of the contents of carbon monoxide and oxygen in the boiler flue gases. [ABSTRACT FROM AUTHOR]

The purpose of this work is to determine the conditions for the rational use of tubular quartz incandescent lamps with a tungsten spiral, in particular, halogen lamps, as part of infrared simulators of external thermal loads on the surface of a spacecraft. The paper represents the results of a study on the feasibility of using tubular incandescent lamps with a tungsten coil as radiation sources in simulators of external thermal loads on the surface of a spacecraft. Tribology of the elements of infrared simulator ensures the reliable operation of mechanisms, which can be broadly grouped into one-shot devices, and continuously and intermittently operating devices. In large and medium-sized thermal vacuum installations intended for conducting thermal vacuum tests of spacecraft (SC) or their individual fragments, among the systems simulating the main factors of the space environment that affect the thermal state of the SC, there are almost always simplified means of reproducing some components of external thermal loads, and sometimes total loads. It is shown that if an acceptable value of the discreteness of the placement of emitters (at least 20) is implemented in the design of the simulator, the density value of the heat flux leaving the simulator, commensurate with the value of the solar constant, can be achieved only at a relatively high temperature of the spiral - more than 1500 K. Based on the study, it was concluded that incandescent halogen lamps can be used in infrared simulators to simulate external thermal loads on spacecraft with uniform and gray radiation-optical characteristics of their surfaces. [ABSTRACT FROM AUTHOR]

Calculations of the stress state of a two-layer system of a thermal barrier coating are performed depending on the thermal loading mode and the presence or absence of a temperature gradient over the sample cross section during the thermal resistance test. The calculations took into account changes in the state of the structure of the coating ceramic layer and the sublayer. A numerical model of the thermal barrier coating performance is developed depending on the thickness ratio of the ceramic layer and the sublayer. [ABSTRACT FROM AUTHOR]

The steam-power equipment of PGU-110 combined-cycle power unit of the Pregolskaya Thermal Power Plant is described. The procedure and conditions of the thermal tests are considered. The thermal characteristics of the power equipment of PGU-110 (gas turbine unit, heat-recovery steam generator, and steam turbine) and the power unit as a whole are presented, and their features are analyzed. The dependences of the main thermal characteristics of the GTU, HRSG, and ST on the determining factors are shown graphically. [ABSTRACT FROM AUTHOR]

In 2019, the fourth 110 MW combined-cycle power unit was commissioned at the Pregolskaya Thermal Power Plant (TPP), the Kaliningradskaya CHP-2 branch of the Inter RAO-Electric Power Plants company. The PGU-110 power unit includes a 77.85 MWgas turbine PG6111FA(manufactured by General Electric) delivered by the Russian Gas Turbines company. Natural gas is used as fuel in the combustion chamber. Detailed tests and studies of the operating modes of the gas turbine in a wide range were carried out in the same year. The test results are presented, and the thermal characteristics of the gas turbine are specified. During the tests, the standard automated measurement system was used. More than 60 stationary modes at various electrical loads and ambient temperatures were studied. The experimental data were processed following State Standard GOST R 55798–2013 (Gas Turbine Installations. Test Methods. Acceptance Tests) and special heat-balance methods. During the tests, the electrical output of the gas turbine varied from 80.1 to 17 MW in the range of external temperatures from +2 to +21°C, while the initial gas temperature in the turbine decreased from 1220 to 1000°C. In the range of loads studied, the NOx emissions at 15% O2 did not exceed 10 ppm. [ABSTRACT FROM AUTHOR]

Polimer malzemelerden üretilen ürünlerin tüketim miktarları ve tüketim artış hızları gün geçtikçe artmaktadır. Bu plastik malzemeler, uzun süre doğada çözünemeyeceğinden dolayı çeşitli kirlilikleri de beraberinde getirmektedir. Ayrıca hemen hemen tüm polimer esaslı ürünler sınırlı kaynak olan petrolden üretilmektedir. Bu nedenle plastik malzemelerin geri dönüşümü ve geri dönüşümü yapılmış malzemelerin özelliklerinin tespit edilmesi büyük önem arz etmektedir. Bu çalışmada birincil geri kazanım yöntemi kullanılarak atık plastiklerden ve orijinal polimer malzemelerden elde edilebilecek ürüne yakın eş değerde ürün elde etmek amaçlanmıştır. Bu çalışmada, orijinal polipropilen (PP) ve Akrilonitril Bütadin Stiren (ABS) malzemesinden MA/G serisi enjeksiyon makinesi ile üç kez geri dönüşümü yapılmış (PP) ve ABS malzeme üretimleri gerçekleştirilmiştir. Üretimi yapılan prototip malzemeler üzerinde; Isı Deformasyon testi (HDT), Eriyik akış endeksi (MFI), Izod Darbe Testi, Çekme Testi ve Sertlik (Shore-D) testleri yapılarak termal ve mekanik özelliklerindeki değişmeler deneysel olarak incelenmiştir. Sonuç olarak, geri dönüşümü yapılmış PP ve ABS numunelerin termal özelliklerinde yaklaşık %30 iyileşme, mekanik özelliklerde yaklaşık %50 azalma gözlenmiştir.

The results from experimental investigations of chamber internal parts and plasma-facing materials proposed for use in a thermonuclear reactor are reviewed. The thermonuclear reactor internals will experience various heat loads connected with temperature gradients and local exposure dose with the nuclear reaction neutron energy spectrum. The lifetime of the systems will depend on the resistance of materials to neutron and heat loads. Assurance of heat removal is one of serious problems to be solved in implementing a thermonuclear power plant. The components can be cooled either by gas or liquid, including salt solutions and liquid metals. The parameters of coolants, heat-transfer systems, and cooling systems will take values that are still not attainable as of yet. The variety of available design elaborations suggested in the Russian and foreign projects must be substantiated in terms of heat transfer. The parameters of heat and neutron loads will govern the choice of materials for the thermonuclear reactor systems. The international thermonuclear experimental reactor (ITER), which is under construction, will be built using structures, materials, and technologies that have passed the main tests. The ITER cooling systems will operate with forced single-phase convection of turbulent water flow; the heat transfer will be intensified by using inner finning and flow swirling. The thermal protection lining of the plasma-facing chamber's internal parts in the zones of the highest plasma and heat load will be made of tungsten. In elaborating the design of the next-generation demonstration reactor (DEMO), it will be necessary to additionally develop the blanket construction technologies and solve the problem of converting heat into electricity. The materials for the DEMO reactor must be selected with due regard to the high dose of their irradiation by neutrons with the thermonuclear reaction energy spectrum and critically high heat loads experienced by the plasma-facing chamber's internals. It will be necessary to develop and test new materials for constructing the DEMO thermonuclear reactor and solve matters concerned with their commercial-scale manufacture. [ABSTRACT FROM AUTHOR]

In this day and age, new products are needed within the structure of environmentally sensitive production methods and for efficient use of Natural Resources and energy to reduce the emissions that cause climate change. Plastic materials take an important place in our daily lives. Polypropylene (PP), which is a thermoplastic polymer material, has a wide range of uses in the automotive industry, manufactory and food packaging, but in some cases it does not provide the desired properties. Composite material is needed to further improve the properties of these materials. Composite materials that are constantly evolving and changing have many advantages such as reducing costs, increasing the efficiency and quality of the product. Some materials used as additives to plastic materials also produce improvements in their mechanical and thermal properties as plastic composites. In this study, 100 standard test bars were produced in the injection machine by making homogenous mixture of % 1 graphite material with commonly used polypropylene (PP) material in double screw extruder machine. Pure polypropylene (PP) izod impact test with the prototype of the product and composite product, Melt Flow Index (MFI), Heat Deformation Test (HDT), hardness test (Shore-D) tensile test and density tests were conducted. According to the test results, some changes in thermal and mechanical properties of pure polypropylene (PP) and Graphite reinforced polypropylene (GPP) composite material were investigated. As a result, the mechanical properties of these two materials have improved by approximately % 30 and thermal properties by approximately % 15. By improving its mechanical and thermal properties it will provide great advantages in the plastics industry. It is also envisaged that it could be used as a new product in the military industry, aviation and automotive sectors. [ABSTRACT FROM AUTHOR]

In this work, we carried out metallographic studies of the lateral and longitudinal sections of the fuel element claddings used in the fuel assemblies of VVER-1000 reactors. The average fuel burnup in these fuel elements during one and six annual campaigns was ~20 and ~70 MWd/kg U, respectively. The effect of long-term thermal tests under simulated dry storage conditions of fuel elements on the hydride morphology in the lateral and longitudinal sections of E110 zirconium alloy claddings was experimentally studied. The test fuel elements were kept in helium at 380°C for 468 days under stationary conditions and from 20 to 380°C (48 cycles, holding time from 1 to 10 days at 380°C) for 427 days during thermal cycling. Metallographic studies of the microstructure of the lateral and longitudinal sections of fuel element claddings were carried out in order to determine the effect of fuel burnup and thermal testing modes on the morphology of zirconium hydrides in the fuel elements from the regions corresponding to the middle of the fuel rod and the gas collector location. It was established that the specific length of hydrides does not exceed 4.5 × 10–3 μm–1 and correlates with a low hydrogen content in the claddings. Thermal tests did not change the hydrogen content in the claddings, but caused an increase in the specific length of hydrides in the lateral sections of the claddings by 1.5–1.9 times in fuel elements with low burnup. In the longitudinal sections of the claddings of these fuel elements, as well as in the fuel elements with a high level of fuel burnup, this coagulation of hydrides was not observed. Thermal tests under stationary conditions and in thermal cycling mode did not lead to a significant change in the hydride orientation, which was predominantly tangential with a high fraction of the chaotic component in the lateral section of the claddings, whereas the axial orientation of hydrides prevailed in the longitudinal section. [ABSTRACT FROM AUTHOR]

The mechanical properties, the dislocation structure, and the morphology of phase precipitates in the E110 alloy fuel claddings worked in the fuel assemblies of a VVER-1000 reactor to a fuel burn-out of 20 and 70 (MW day)/kgU are studied. The influence of the thermal conditions that model the fuel element dry storage conditions on the annealing of radiation defects and the recovery of the mechanical properties of the claddings is analyzed. [ABSTRACT FROM AUTHOR]

This paper presents the results of testing specimens of porous carbon–ceramic composite materials on the high-temperature gas-dynamic plasmatron VGU-4. The structure of carbon–ceramic composite materials of various densities before and after tests has been investigated. It has been shown that the porosity of such a material influences the process of its thermal destruction and ablation in a high-enthalpy gas flow. [ABSTRACT FROM AUTHOR]

A method is proposed for selecting the test-chamber parameters for ground thermal testing of spacecraft radioelectronic equipment operating in brief communication sessions. By this method, expensive and laborious testing of such equipment in thermal vacuum chambers may be partially replaced by tests in a climate chamber. The results of dynamic thermal tests of a standard radioelectronic module in a thermal vacuum chamber and a climate chamber are compared. [ABSTRACT FROM AUTHOR]

For the new generation of space vehicles with a reusable heat shield, it is promising to use carbon-ceramic composite materials resistant to powerful heat flows arising by the descent of such a vehicle in the atmosphere. This paper presents the results of the theoretical forecast of characteristics of a heat shield from a porous carbon–ceramic composite made on the basis of testing specimens of this composite on a gas-dynamic stand simulating real operating conditions of the heat shield. Methods have been developed for simulating the heating and ablation of specimens of carbon–ceramic composites under their convective heating in a plasmatron. It has been established that the diameter of the nozzle of the gas-discharge channel of the plasmatron and its distance to the frontal surface of the specimen influence the temperature regime of tests. We propose an experimental procedure for attaining a temperature of 273 K on the frontal surface of a cylindrical specimen of a carbon–ceramic composite material of diameter 70 mm and height 70 mm. [ABSTRACT FROM AUTHOR]

The results of testing samples made of T700 carbon fiber reinforced plastic with a stress concentrator in the form of a hole 14 mm in diameter are considered. Some of the samples were heated to a temperature of +100°C, followed by exposure to a static tensile load, with the remaining samples statically loaded at a temperature of +20°C. In the process of loading, information was recorded using the method of acoustic emission. At first, the samples were loaded statically up to 50 kN, which was 50% of the average breaking load. Then the load was increased in increments ΔP = 10 kN until sample failure. It was observed that the simultaneous exposure of samples to static and heat loads decreased the load capacity of the samples. [ABSTRACT FROM AUTHOR]

The mechanical properties of polymer composites (PC), in particular, carbon fiber reinforced plastics with operating temperatures up to 150°C, are studied and compared. A number of compression tests of the composite samples reinforced by carbon fiber with a solvent-based and adhesive matrix are carried out according to ASTM D 695 using a thermal test chamber. The strength characteristics of PC samples reinforced by the carbon fiber and adhesive matrix T-107 are found to be higher than that of modern carbon composites with solvent- and melt-based matrices. [ABSTRACT FROM AUTHOR]

This paper presents some practical issues and experience acquired in the design and experimental verification of a small-sized solar concentrator producing both electrical and thermal power. The device is a low-concentration photovoltaic/thermal solar system with a 20 suns ( $20\times $ ) concentrator factor and is suitable for integration on building roofs. It consists of four small-sized ( $1930 \times 250 \times 166$ L $\times $ W $\times $ H mm) linear focus semiparabolic mirrors mechanically linked and driven by a stepper motor and tracking the sun along a single axis. The sunrays are concentrated on strings of monocrystalline cells with conversion efficiency of about 18%. One of the main features of this device is that the parabola mirrors are designed to have their focus inside the mirror profile so that the solar receiver is installed inside the parabolic concentrator. As a result, each single concentrator height is as low as 166 mm. The solar energy that is not converted into electricity by the solar cells is recovered by a cooling medium flowing in an aluminum structure on which the PV cells are mounted. This paper presents an overall description of the device, an electrical layout of the bypass diodes of the solar receiver utilized to reduce the end losses, a method based on voltage measurement to derive the solar cell temperature inside the receiver, and a set of results derived from experimental validations performed on a device prototype. This paper also describes the monitoring system utilized for measurements on the solar concentrator and derives an overall efficiency of solar energy conversion in both electric and thermal generation as high as 61.5%. The predicted values were in good agreement with the experimental test results. [ABSTRACT FROM AUTHOR]

Test results at different loads and ambient temperatures for LMS100 PB gas-turbine units at the Dzhubga thermal power plant are discussed. The performance indicators for these gas turbine units and their turbine equipment, combustion chambers, and air cooling systems are determined. The gas-turbine units produce the design power (normally about 90 MW, and up to 95 - 99 MW when necessary) with a gross efficiency of 42.3 - 42.7% with moderate (no more than 20 - 35 mg/m) atmospheric emissions of nitrogen oxides (under normal conditions). The differences in the performance of individual components of the gas-turbine units are within the limits of error in the measurements. [ABSTRACT FROM AUTHOR]

This paper studies the role of a binder in ensuring the efficiency of a thermal insulation material (TIM) based on glass microspheres. A one-criterion experimental assessment of the synergism of the composite thermal insulation components based on glass microspheres in terms of strength indicators in relation to the power and thermal loads, minimum thermal conductivity, and minimum density made it possible to recommend a certain type of binder to select TIMs under continuous operation at high temperatures. [ABSTRACT FROM AUTHOR]

Abstract: Polymer samples based on polydicyclopentadiene produced from Russian dicyclopentadiene are investigated by thermogravimetric analysis and differential scanning calorimetry. A second stage of polymerization—that is, heat treatment of the samples—is found to increase the degree of polymerization and improve the physicomechanical properties of the polydicyclopentadiene. [ABSTRACT FROM AUTHOR]

Avionics represents of the most important industrial sector where innovation is a key issue. In order to guarantee that any new device introduced onboard has an adequate quality and reliability level, testing activity is fundamental to help engineers and technicians to verify their designs and prevent any safety critical failures. National regulatory agencies and standards organizations, such as, the European Union Authority for aviation safety (European Aviation Safety Agency – EASA), the United States defense standard, often called military standard (MIL-STD) carried out by the U.S. Department of Defense or the Radio Technical Commission for Aeronautics (RTCA), have developed several test procedures that have to manage with the customer requirements. This paper is focused on the experimental results related to the validation process of a custom TFT-LCD for avionics applications. Environmental tests and, in particular, optical measurements will be described in detail in order to underline the key role that test plannig and measurements represent in aerospace applications. [ABSTRACT FROM AUTHOR]

The current work reports a novel approach for the integration of external protective SiC multilayers with ceramic matrix composite (C f /SiC) with the view of application in aerospace heat protection systems. The integration method is based on diffusion brazing bonding. As a joining agent the MAX-Phase Ti 3 SiC 2 , produced by self-propagating high temperature synthesis, has been employed. The pressure applied during the joining process and its effect on the microstructure of the integrated structure is discussed. Microstructural analysis of the resulting joints is conducted using scanning electron microscopy coupled with energy dispersive spectroscopy and X-ray diffraction measurements. Analysis of the joints showed that the bonds are uniform, dense, with few crack vertical to the interface which are not detrimental for the performance of the joints. Ground re-entry tests showed that the joints survive 5 re-entry cycles at 1391 and 1794 °C without any detectable damage. [ABSTRACT FROM AUTHOR]

The thermal performance of solar ovens has been thoroughly discussed over the years by many researchers who took the time to study the subject. There are many contributions in this area. This paper aims to establish a comparison between the results obtained from a methodology proposed in the bibliography consulted and those obtained with the simulation carried out with SIMUSOL, especially when comparing the overall loss coefficients with the simulated ones and the ovens' performance under different test conditions. [ABSTRACT FROM AUTHOR]

Ways for improving the turbine district heating installations of single-circuit nuclear power plants are considered as a possible approach to improving the nuclear power plant energy efficiency. The results of thermal tests carried out at one of single-circuit NPPs in Russia with a view to reveal the possibilities of improving the existing heat-transfer equipment of the turbine district heating installation without making significant investments in it were taken as a basis for the analysis. The tests have shown that there is certain energy saving potential in some individual units and elements in the turbine district heating installation's process circuit. A significant amount of thermal energy can be obtained only by decreasing the intermediate circuit temperature at the inlet to the heater of the first district-heating extraction. The taking of this measure will also lead to an additional amount of generated electricity because during operation with the partially loaded first heater, the necessary amount of heat has to be obtained from the peaking heater by reducing live steam. An additional amount of thermal energy can also be obtained by eliminating leaks through the bypass control valves. The possibility of achieving smaller consumption of electric energy for power plant auxiliaries by taking measures on reducing the available head in the intermediate circuit installation's pump unit is demonstrated. Partial cutting of pump impellers and dismantling of control valves are regarded to be the most efficient methods. The latter is attributed to qualitative control of the turbine district heating installation's thermal load. Adjustment of the noncondensable gas removal system will make it possible to improve the performance of the turbine district heating installation's heat-transfer equipment owing to bringing the heat-transfer coefficients in the heaters to the design level. The obtained results can be used for estimating the energy saving potential at other similar NPPs and may be taken into account in developing new power installations. [ABSTRACT FROM AUTHOR]

The experience of using honeycomb seals in the steam path of T-100-130 turbines made by the Ural Turbine Works is discussed. The data of thermal tests conducted to assess the effectiveness of honeycomb shroud seals in the HPC of the T-110/120-130-4 turbine of Unit No. 2 of the Mosenergo CPP-21 are reported. The damage of axial/radial and honeycomb shroud seals by foreign objects is examined. A technical evaluation procedure and the experience of repairing honeycomb seals damaged during operation are described. [ABSTRACT FROM AUTHOR]

Since anticonvulsants have been used for treating neuralgias, an interest has arisen to experimentally test vigabatrin for its gabaergic mechanism of action. For this, 41 Wistar rats were used, and in 25 of them a constrictive sciatic neuropathy was induced (Bennet & Xie model). For testing pain symptoms, spontaneous (scratching) and evoked behaviors to noxious (46o C) and non-noxious (40o C) thermal stimuli were quantified. Moreover, a comparative pharmacological study of vigabatrin with other analgesic anticonvulsant drugs was also performed. The results showed a possible dose-dependent analgesic effect of vigabatrin (gamma-vinyl-GABA) on experimental neuropathic pain, as shown by the significant (p

We assessed the effect of sleep deprivation on the pain thresholds in the thermal and chemical nociceptive tests. Adult male Wistar rats and mice were randomly assigned to the three groups, with no sleep deprivation (control), subjected to 24-h-long sleep deprivation, and sleep-deprived and treated with either an H2 (histamine) receptor antagonist, cimetidine, or a cholinergic receptor blocker, atropine, before deprivation. Sleep deprivation led to significant decreases in both hot plate and tail withdrawal latencies in the thermal tests, a significant increase in the number of writhings in the acetic acid-induced writhing test, and significant prolongation of the licking time in the formalin test ( P < 0.05 in all cases). All changes in the thermal and chemical tests denote noticeable hyperalgesia. Prior administration of both cimetidine and atropine significantly reversed these hyperalgesic changes caused by sleep deprivation as revealed by increases in the thermal latencies in both tests used. We, therefore, conclude that both histaminergic and cholinergic systems play significant roles in sleep deprivation-induced hyperalgesia. [ABSTRACT FROM AUTHOR]

Practical experience with the introduction of honeycomb seals in the flow-through sections of 250 - 800 MW steam turbines with supercritical steam pressure is examined. The most widespread designs for shroud and end honeycomb seals used in the development of new turbine units are discussed, along with the modernization of existing steam turbine equipment. Test stand data on the relative flow rate and power characteristics of honeycomb, radial, and axial-radial seals are compared. Results are reported from thermal tests for evaluating the efficiency of installing honeycomb shroud seals in the high pressure cylinders of the T-250_300-240 turbine units at the TÉTs-21 plant of JSC 'Mosénergo' and the K-800-240-5 turbine units at the Perm GRÉS plant of JSC 'OGK-1.' [ABSTRACT FROM AUTHOR]

Alternative thermal barrier coating, functionally graded Al 2 O 3 /CYSZ was investigated for CMAS and hot corrosion melts attack under high temperature. Two different test setups were used to simulate the harsh environment of gas turbine engines. Thermal gradient and thermal cycling tests were carried out by using a static heat source laser. Commercial single-layer CYSZ was used as a comparison. As a result of XRD analysis and with the help of Rietveld refinement, the monoclinic transformation was compared for both TBCs. While there was no tetragonal-monoclinic transformation for a functionally graded coating because of protective inert alumina surface, CYSZ has %12.3 and %66.4 monoclinic transformation after thermal gradient and thermal cycle test at 1200 °C, respectively. The t-m transformation resulted in the failure of TBC because of the volume extension of zirconia and the TBC system. Microstructure, EDS and XRD analysis were performed to determine the failure of TBCs. • Ceria-yttria stabilized zirconia (CYSZ, ZrO 2 , 24CeO 2 , 2.5Y 2 O 3) and alumina (α-Al 2 O 3) were produced with functionally graded design by atmospheric plasma spray (APS) process. • Thermal gradient and thermal cycling tests were performed in the presence of CMAS and hot corrosion salt-powder at 1200 °C. • Tetragonal-monoclinic zirconia phase transformation was measured by using Rietveld analyzes to understand the destabilization and failure of the coatings. • Functionally graded design Al 2 O 3 /CYSZ compared with commercial single-layered CYSZ TBC for hot corrosion and CMAS degradation. [ABSTRACT FROM AUTHOR]

Highlights: [•] Prototype ITER neutral beam injector to study the beam source behavior requires beam characterization. [•] Among several types of diagnostic, a calorimeter made of fiber carbon composite (CFC) tiles will be used. [•] The CFC thermal behaviour is study by laser beam and will be characterize in particel beam. [•] Experiments and simulations results are discussed. [•] Designs for tests in particle beams are presented. [Copyright &y& Elsevier]

The thermal configuration of a single-shaft steam gas unit (PGU-400) operating at the Shatura State Regional Electric Power Plant (Shatura GRÉS) and its basic equipment are described and the techniques and conditions for thermal tests are examined. The thermal characteristics of the steam-gas unit equipment (gas turbine, boiler-utilizer, and steam turbine) and of the power generating unit as a whole derived from these tests are reported and their features are analyzed. The major thermal characteristics of the PGU-400 are graphed as functions of the determining factors. [ABSTRACT FROM AUTHOR]

A procedure for thermal-vacuum tests for elements of real rod structure in spaces is presented. The procedure makes it possible to determine the heat conductivity of polymer-composite materials in a wide range of temperatures. According to the procedure, the tested samples are cooled by liquid nitrogen and heated by a contact method. The experimental data are processed by solving the coefficient inverse problem of heat conductivity. [ABSTRACT FROM AUTHOR]