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Using the example of the energy sector and the agricultural sector of Uzbekistan, the article shows the possibility of incorporating the technical parameters of typical green and energy-saving ...projects into the basic input–output model, obtaining estimates of the impact made by such projects on the financial sustainability of the relevant industries. Approaches are reviewed to combining long-term scenario forecasts for the development of the industry with model calculations of macroeconomic, environmental, and social consequences that allow an unambiguous economic interpretation, as well as to choosing the directions of green transformation that are the most promising in terms of a set of criteria, including social ones. The purpose of the work is to show the possibility of taking into account the national interests of Uzbekistan when substantiating the green transformation model using a methodology that combines detailed input–output models with engineering calculations for specific green investment projects and estimates of demand for the investment resources necessary for their implementation.
Tetraphenyl butadiene (TPB) is widely used in particle detectors as a wavelength shifter. In this work we studied the stability of TPB thin films when immersed in liquid xenon (LXe). The thin films ...were deposited on glass and quartz substrates by thermal evaporation. Morphological and chemical surface properties were monitored before and after immersion into LXe by scanning electron microscopy and X-ray photoelectron spectroscopy. No appreciable changes have been detected with these two methods. Grain size and surface chemical composition were found to be identical before and after submersion into LXe. However, the film thickness, measured via optical transmission in the ultraviolet–visible wavelength regions, decreased by 1.6μg/cm2 (24%) after immersion in LXe during 20h. These results suggest the necessity of using a protective thin film over the Tetraphenyl butadiene when used as a wavelength shifter in LXe particle detectors.
•Stability of tetraphenyl butadiene (TPB) thin films immersed in liquid xenon (LXe).•Thermally evaporated TPB thin films were immersed in LXe for 20h.•Film morphology and chemical surface properties remained unchanged.•Surface density of the films decreased by 1.6μg/cm2 (24%) after immersion in LXe.•For using in LXe particle detectors, TPB films should be protected with a coating.
Compact gamma cameras with a square-shaped monolithic scintillator crystal and an array of silicon photomultipliers (SiPMs) are actively being developed for applications in areas such as small animal ...imaging, cancer diagnostics and radiotracer guided surgery. Statistical methods of position reconstruction, which are potentially superior to the traditional centroid method, require accurate knowledge of the spatial response of each photomultiplier. Using both Monte Carlo simulations and experimental data obtained with a camera prototype, we show that the spatial response of all photomultipliers (light response functions) can be parameterized with axially symmetric functions obtained iteratively from flood field irradiation data. The study was performed with a camera prototype equipped with a 30 × 30 × 2 mm
LYSO crystal and an 8 × 8 array of SiPMs for 140 keV gamma rays. The simulations demonstrate that the images, reconstructed with the maximum likelihood method using the response obtained with the iterative approach, exhibit only minor distortions: the average difference between the reconstructed and the true positions in X and Y directions does not exceed 0.2 mm in the central area of 22 × 22 mm
and 0.4 mm at the periphery of the camera. A similar level of image distortions is shown experimentally with the camera prototype.
Statistical event reconstruction techniques can give better results for gamma cameras than the traditional centroid method. However, implementation of such techniques requires detailed knowledge of ...the photomultiplier tube light-response functions. Here we describe an iterative method which allows one to obtain the response functions from flood irradiation data without imposing strict requirements on the spatial uniformity of the event distribution. A successful application of the method for medical gamma cameras is demonstrated using both simulated and experimental data. An implementation of the iterative reconstruction technique capable of operating in real time is presented. We show that this technique can also be used for monitoring photomultiplier gain variations.
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Based on the generalization of the world’s existing approaches to modeling the consequences of limiting energy subsidies in relation to Uzbekistan, the necessity of using the input–output method in ...its various modifications is substantiated. The developed model structure is based on three channels of distribution of the shock to the economy, the employed and the environment from the restriction of energy subsidies: price, investment and structural. Each of them models different effects of restricting energy subsidies: rising energy tariffs and their impact on output and overall inflation rate; assessment of additional budget revenues in comparison with shortfall in tax revenues due to the slowdown in the growth of energy-intensive industries; negative effects on employment and incomes of the population; positive effects for the environment; growth of external debt during the implementation of green investment projects and a number of others. Using the example of Uzbekistan, the article discusses the results of modeling the consequences of the implementation of various scenarios for the reform of energy subsidies at the macro and sectoral levels, the effects on the environment and financial sustainability. At the same time, issues of limiting the negative social consequences of the reform of energy subsidies by introducing energy efficient technologies and renewable energy sources, stimulating final demand, and slowing down the rate of reduction of subsidies were studied.
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