Nanomaterials and nanotechnology for sustainable energy

Upotreba nanotehnologija u cilju razvijanja načina proizvodnje održive energije je jedan od najznačajnijih izazova 21 veka. Izazov je dizajnirati, sintetizovati i izvršiti karakterizaciju novih funkcionalnih nanomaterijala kontrolisanih veličina, oblika i/ili struktura. Nanotehnologija danas privlači punu pažnju ne samo akademske zajednice, već i investitora, vlada i privrede a radi izgradnje i ostvarivanja velikih očekivanja. Ovaj rad istražuje moguću primenu nanotehnologija za nove i unaprijeđene metode pretvaranja energije, uvažavajući potrebe naše sredine. Njihova je jedinstvenost u tome što imaju mogućnost da fabrikuju nove structure na atomskom nivou, kao što su već proizvedeni novi materijali i uređaji sa mogućnošću visoko potencijalne primene u mnogo oblasti. Fokus je na bitnoj ulozi nanomaterijala, pripremi i karakterizaciji nekih nanomaterijala za proizvodnju održive energije, tankoslojnih solarnih ćelija u tehnologiji proizvodnje energije vodonikom.The use of nanotechnology to develop a suite of sustainable energy production schemes is one of the most important scientific challenges of the 21st century. The challenge is to design, to synthesize, and to characterize new functional nanomaterials with controllable sizes, shapes, and/or structures. Nanotechnology is generating a lot of attention these days and therefore building great expectations not only in the academic community but also among investors, the governments, and industry. This paper, explores some of the possible implementations of nanotechnology for new and improved methods of energy conversion, considering a need for this to be done without compromising our environment. Its unique capability to fabricate new structures at atomic scale has already produced novel materials and devices with great potential applications in a wide number of fields. Focus is given to important role of nanomaterials, preparation and characterization some of nanomaterials important for sustainable energy, dye sensitized solar cels and hydrogen production technology

Nanomaterials and nanotechnology for sustainable energy

Upotreba nanotehnologija u cilju razvijanja načina proizvodnje održive energije je jedan od najznačajnijih izazova 21 veka. Izazov je dizajnirati, sintetizovati i izvršiti karakterizaciju novih funkcionalnih nanomaterijala kontrolisanih veličina, oblika i/ili struktura. Nanotehnologija danas privlači punu pažnju ne samo akademske zajednice, već i investitora, vlada i privrede a radi izgradnje i ostvarivanja velikih očekivanja. Ovaj rad istražuje moguću primenu nanotehnologija za nove i unaprijeđene metode pretvaranja energije, uvažavajući potrebe naše sredine. Njihova je jedinstvenost u tome što imaju mogućnost da fabrikuju nove structure na atomskom nivou, kao što su već proizvedeni novi materijali i uređaji sa mogućnošću visoko potencijalne primene u mnogo oblasti. Fokus je na bitnoj ulozi nanomaterijala, pripremi i karakterizaciji nekih nanomaterijala za proizvodnju održive energije, tankoslojnih solarnih ćelija u tehnologiji proizvodnje energije vodonikom.The use of nanotechnology to develop a suite of sustainable energy production schemes is one of the most important scientific challenges of the 21st century. The challenge is to design, to synthesize, and to characterize new functional nanomaterials with controllable sizes, shapes, and/or structures. Nanotechnology is generating a lot of attention these days and therefore building great expectations not only in the academic community but also among investors, the governments, and industry. This paper, explores some of the possible implementations of nanotechnology for new and improved methods of energy conversion, considering a need for this to be done without compromising our environment. Its unique capability to fabricate new structures at atomic scale has already produced novel materials and devices with great potential applications in a wide number of fields. Focus is given to important role of nanomaterials, preparation and characterization some of nanomaterials important for sustainable energy, dye sensitized solar cels and hydrogen production technology

REVIEWING THE PHOTOVOLTAIC POTENTIAL OF BIJELJINA IN THE REPUBLIC OF SRPSKA

To estimate PV potential of Bijeljina, PVGIS and SOLARGIS databases were used. The results showed that Bijeljina municipality has an average daily PV power potential of 3.50 kWh/kWp, thus belonging to areas with the favorable mid-range PV power potential values. Average levelized cost of electricity is $0.12/kWh, consequently making PV technologies in Bijeljina also economically competitive with conventional power-generating sources. In the light of the rapid development of photovoltaic technology, this paper gives a critical review of previous studies and suggests that the application of PV technologies has become even more attractive. High-efficiency PV modules and grid inverters were tested on examples of roof-mounted PV systems and ground-mounted PV system using specialized PVSYST software. Comparison of the obtained results with previous studies gave a clear picture with advantages of these new solutions, and further support for PV technologies utilization

THE STUDY OF ENERGY EFFICIENCY OF MONOCRYSTALLINE SILICON MODULES

This paper presents the effect of temperature and wind speed on physical characteristics of monocrystalline silicon solar modules, which are placed on the building of the Academy of Sciences and Arts of the Republic of Srpska in Banja Luka. Measurements of the solar modules were carried out by UI analyzer for photovoltaic PV-KLA and Mini PV-KLA. Meteorological parameters (temperature, wind speed and intensity of solar radiation) were measured using the automatic meteorological station Davis Vantage Pro-USA. This paper gives the results of comparisons between theoretically obtained energy efficiency and experimentally obtained energy efficiency of the monocrystalline silicon modules in relation to their characteristics.This paper presents the effect of temperature and wind speed on physical characteristics of monocrystalline silicon solar modules, which are placed on the building of the Academy of Sciences and Arts of the Republic of Srpska in Banja Luka. Measurements of the solar modules were carried out by UI analyzer for photovoltaic PV-KLA and Mini PV-KLA. Meteorological parameters (temperature, wind speed and intensity of solar radiation) were measured using the automatic meteorological station Davis Vantage Pro-USA. This paper gives the results of comparisons between theoretically obtained energy efficiency and experimentally obtained energy efficiency of the monocrystalline silicon modules in relation to their characteristics

EXPERIMENTAL DETERMINING OF ENERGY EFFICIENCY OF PV SOLAR POWER PLANT AT THE FACULTY OF SCIENCES AND MATHEMATICS IN NIŠ

This paper presents basic information on a 2 kW solar power plant at the Faculty of Sciences and Mathematics in Niš and the equipment for its energy efficiency determination depending on the real meteorological conditions (inverter, communication system, sensor, etc.). Additionally, the results are shown of experimental determination of energy efficiency of the solar power plant at the Faculty of Science and Mathematics in Niš from June 1, 2013 to September 1, 2013 (energy of the Sun radiation, ambient temperature, wind velocity, generated electrical energy, etc.).This paper presents basic information on a 2 kW solar power plant at the Faculty of Sciences and Mathematics in Niš and the equipment for its energy efficiency determination depending on the real meteorological conditions (inverter, communication system, sensor, etc.). Additionally, the results are shown of experimental determination of energy efficiency of the solar power plant at the Faculty of Science and Mathematics in Niš from June 1, 2013 to September 1, 2013 (energy of the Sun radiation, ambient temperature, wind velocity, generated electrical

Evaluation of patient specific quality assurance of gated field in field radiation therapy technique using two-dimensional detector array

Introduction: Gated tangential field-in-field (FIF) technique is used to lower the dose to organs at risk for breast cancer radiotherapy (RT). In this study, the authors investigated the accuracy of the delivered treatment plan with and without gating using a two-dimensional detector array for patient-specific verification purposes.Methods: In this study, a 6MV beams were used for the merged FIF RT (forward Intensity Modulated Radiation Therapy). The respiration signals for gated FIF delivery were obtained from the one-dimensional moving phantom using the real-time position management (RPM) system (Varian Medical Systems, Palo Alto, CA). RPM system used for four-dimensional computed tomography scanner light-speed, GE is based on an infrared camera to detect motion of external 6-point marker. The beams were delivered using a Clinac iX (Varian Medical Systems, Palo Alto, CA) with the multileaf collimator Millennium 120. The MapCheck2 (SunNuclear, Florida) was used for the evaluation of treatment plans. MapCheck2 was validated through a comparison with measurements from a farmer-type ion chamber. Gated beams were delivered using a maximum dose rate with varying duty cycles and analyzed the MapCheck2 data to evaluate treatment plan delivery accuracy.Results: Results of the gamma passing rate for relative and absolute dose differences for all ungated and gated beams were between 95.1% and 100%.Conclusion: Gated FIF technique can deliver an accurate dose to a detector during gated breast cancer RT. There is no significance between gated and ungated patient-specific quality assurance (PSQA); one can use ungated PSQA for verification of treatment plan deliver

Computed tomography simulator conversion curve dependence on scan parameters and phantom dimension

Introduction: Using computed tomography (CT) and treatment planning systems (TPS) in radiotherapy, due to the difference in photon beam energy on CT and linear accelerator, it is necessary to convert Hounsfield units (HU) to relative electron density (RED) values. The aim of this dosimetric study was to determine whether there is a significant effect of potential in the CT tube, field of view size (FOV), and phantom dimensions on the CT conversion curve CT-RED. The second aim is whether there are significant differences between the CT-RED obtained by the Computerized Imaging Reference Systems (CIRS) Thorax 002LFC phantom and the “reference” curve in the TPS, obtained by the CIRS 062M pelvis phantom, at the same CT conditions.Methods: Heterogeneous CIRS 062M and CIRS Thorax 002LFC phantoms were used, which anatomically and dimensionally represent the human pelvis, head, and thorax, with a set of known RED inserts. They were scanned on a CT LightSpeed GE simulator and obtained CT-RED.Results: The high voltage in the CT tube had a significant effect on the HU (t = 10.72, p < 0.001) for RED values >1.1, while FOV as a parameter did not show statistical significance for the 062M pelvis phantom. Comparing the slopes (062M pelvis and head) of the CT-RED for RED ≥ 1.1, the obtained value is t = 1.404 (p = 0.163). In the case of a 062M pelvis and a 002LFC phantom, we have seen a difference in RED values (for the same HU value) of 5 % in the RED region ≥ 1.1 (bone).Conclusion: Patients should be imaged on a CT simulator only at the potential of the CT tube on which the conversion curve was recorded. The influence of the FOV and scanned phantom dimensions is not statistically significant on the appearance of the calibration curve (RED ≥ 1.1)

Single Photon Eigen-Problem with Complex Internal Dynamics

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Integration of solar energy by nature-inspired optimization in the context of circular economy

The purpose of this paper is to make a research on solar power plants integration in an electric power system, taking into account all costs arising from circular economy criteria. Four scenarios of solar power plant installation are analyzed. The methodology relies on nature-inspired optimization. The evolutionary multiobjective genetic algorithm is applied. The optimization is based on the costs of electricity production, encompassing not only the costs of technology, but also the costs of environmental protection and sustainable development. These costs are included in the model and the objectives are formulated accordingly. The objectives are based on maximization of electricity production up to the level of demand, minimization of total electricity costs and minimization of greenhouse gas emissions. In addition, grid losses as well as other limitations and constraints of the electric power system are included into the model. The loss distribution is calculated in proportion to the distance between the supplier and the end user. The solar power plant losses equal zero, because it is assumed that the plant is located in a local community, close to consumers. The results show that the emissions and costs are higher without an introduced solar power plant. Introduction of solar capacities reduces the costs and emissions to a certain level. The developed model may be useful as a decision-support system generator