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Abstract Brown and Ladner's parameters have been compared with those of Williams for the same conditions. The combination of experimental data from 1H n.m.r. and 13C n.m.r. spectra gives the value of the Brown and Ladner's parameter H aru C ar . A comparison of the H aru C ar values was performed on a group of different coal oil samples.

It is important to reduce the amount of municipal waste deposited in landfills, Czech Republic, therefore, puts more emphasis on the recovery of mixed municipal waste, which oblige and EU regulations. Production of solid alternative fuel that is suitable also due to less consumption of fossil fuels, is one of the uses of mixed municipal waste (Waste to Energy). A relatively high proportion of glass in mixed municipal waste is a major problem in the production of solid alternative fuel. The glass contained in the solid alternative fuel can be the cause of formation incrusts on heat transfer surfaces in combustion plants. For all examined types of glass, it was found that the melting temperature of the muffle furnace was 750 ° C. When using the method (ISO 540) for determining the temperature of softening , melting and flow showed no effect of the amount of glass in the ash, but the melting point was significantly higher (around 1,200 °C).

Abstract A new generalized lamp model capable of simulating a lamp’s luminous flux in the time domain is presented. Reference is made to low power lamps (up to 25 W). The generalized lamp model consists of a model of the electrical circuit of the lamp and a model of the bulb itself and is based on the use of only three input parameters. The results of a preliminary experimental analysis are first presented with the aim of justifying the hypotheses of the model. Then, the model is described and used to analyze the frequency behavior of a lamp in the presence of voltage fluctuations; the model was experimentally validated for different kind of lamps. Finally, the results of a sensitivity analysis of the model versus its main parameters are presented.

Abstract One factor that significantly limits blade service life and reliability in GT-100 power turbines is sulphide-oxide metal corrosion of guide and rotating blades. Application of coatings is the most efficient method to prevent corrosion failure. An electron beam physical vapour deposition CoCrAlY coating is used for high and low pressure turbine first-stage rotating blades made from E1 893 alloy. Studies of CoCrAlY-coated blades after different service periods (from 390 to 5900 h) showed that this coating most efficiently protects rotating blades in turbines which operate in northern regions of the country. Because of low temperature hot corrosion leakage, corrosion failure is observed in turbines operating in southern regions of the country. In order to improve corrosion resistance, a ceramic coating has been developed. These coatings increase the endurance of equipment and make it possible to save energy.

The paper proves the economic feasibility of using a local autonomous source of energy supply, which is formed from electrical equipment of other functional purposes based on an asynchronous machine with capacitive self-excitation. To assess the technical and economic indicators of the effectiveness of introducing a local autonomous source of energy supply, the discounted method is adopted, where an indicator of savings from possible losses due to the exclusion of labor resources from production is used as an additional influence factor.

For the evaluation of the detection and measurement limits for gamma-spectrometry measurements formulas were elaborated assuming the presence of the background component, which correlates with the analytical peak in the sense of: (1) linear relation between the expectation value of the peak and background counts, and (2) statistical correlation between peak and background counts. It is shown that neglecting the correlated background component can lead to a significant overestimation of the detection and measurement limits. The problem of evaluating of the correlated background component by applying experimental and computational approaches is also considered.

Abstract A major problem in the operation of photovoltaic (PV) panels is the need for frequent maintenance and cleaning. In the present work, the effect of a self-cleaning, photocatalytic, antireflective glass coating on the efficiency of PV panels is investigated. The optical and photocatalytic properties of the coating were determined via UV–vis spectroscopy and degradation of organic pollutant Methylene Blue, respectively. Increased light transmittance in the visible light region and enhanced self-cleaning of the coated in comparison to the uncoated glass was demonstrated. The adhesion and the stability of the coating were tested in conditions of thermal fluctuations, UV weathering and sandblasting. The outdoor performance of coated and uncoated PV panels and arrays were monitored for several months at different climate conditions (Greece and China) in order the extra energy produced due to coating to be measured. An average 5–6% gain was found for both cases for the entire period of time. It was established that specific conditions such as intensity and angle of the incident light, occurrence of rain and sand storms influence significantly the power difference (ΔPm) between coated and uncoated PV panels. The increase of ΔPm under diffused light (cloudy day) and irradiation with high incident angle (morning, evening) reached ∼20% and 30% respectively, that were related to the anti-reflecting property of the glass coating. The coated surface showed better dust removal ability due to its superhydrophilicity (θ = 6°). The superior efficiency of coated panels as well as the low-cost spraying procedure without any post-deposition treatment render the nanocomposite SurfaShield G coating very important especially for northern regions with limited sunlight periods.