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401.
Nemanja Stanisavljević Živko Jovanović Tihomir Čupić Jovanka Lukić Jovanka Miljuš Đukić Svetlana Radović Aleksandar Mikić 《International Journal of Food Science & Technology》2013,48(10):2096-2104
Antioxidant activities were studied in methanolic and water extracts of nonprocessed, cooked and in vitro enzymatically digested seed flour, as well as in total protein hydrolysates and small peptide fractions (<3 and <10 kDa) of three pea and five grass pea cultivars. The antioxidative properties were determined by three spectrophotometric methods: 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) radical scavenging assay, Folin‐Ciocalteu (FC) reducing capacity assay and H2O2 scavenging. We also applied one luminometric assay for hydroxyl radical scavenging. The study showed that cooking and enzymatic digestion strongly enhanced the release of phenolic compounds in methanolic extracts of four analysed cultivars. Scavenging activity against DPPH radical, hydroxyl radical and hydrogen peroxide was increased in majority of analysed flour specimens subjected to processing. Our findings indicate that, besides the phenolic compounds, the small peptide fraction, especially the MW <3 kDa, in methanolic and aqueous extracts of cooked and digested seed flour significantly contribute to free radical and hydrogen peroxide scavenging activity in all investigated cultivars. Our data strongly suggest that simple cooking treatment and in vitro digestion of seed flour applied prior to extraction with methanol could improve antioxidative activity of obtained extracts. 相似文献
402.
Siniša N. Dodić Tamara Zelenović Vasiljević Radenko M. Marić Aleksandar J. Radukin Kosanović Jelena M. Dodić Stevan D. Popov 《Renewable & Sustainable Energy Reviews》2012,16(5):2355-2360
The Autonomous Province of Vojvodina is an autonomous province in Serbia, containing about 27% of its total population according to the 2002 Census. It is located in the northern part of the country, in the Pannonian plain. Fruska Gora is a lonely island mountain in the Pannonian plain. The research presented in this paper highlights the potential of significant contributing to waste wood biomass in the Park “Fruska Gora (Vojvodina, Serbia) and points to the possibility of using biomass for briquettes production—the final product that can be used for energy purposes. The amount of woody biomass per hectare can be calculated if the data about the average number of trees per hectare are known. For the analyzed case, the value found in 1 ha was 383.1 m3/ha or 272 ± 14 tons, and practically measured value was 402 m3/ha, or 289 tons. The relative deviation of calculated and obtained values of Canadian poplar wood biomass per hectare was 5.88%. Quantities of planned wood waste biomass can be used to produce high-quality briquettes for thermal energy generation purposes in the equivalent of 4.8 million kWh. The large energy potentials, in Vojvodina are still substantially unused, and besides of using waste wood from forestry, it is necessary to consider the sustainable use of available waste biomass from the timber industry. 相似文献
403.
Jovana A. Grahovac Jelena M. Dodić Siniša N. Dodić Stevan D. Popov Damjan G. Vučurović Aleksandar I. Jokić 《Renewable & Sustainable Energy Reviews》2012,16(5):3270-3274
Due to the reduction of the economic support for refined sugar efforts have been made to find new ways of using sugar beet outside food industry. This paper investigates the possibilities of introducing bioethanol co-production in Serbian sugar plants. Research shows current state of Serbian sugar industry and technical aspects of bioethanol co-production in sugar plants. These results represent important step toward mass production of bioethanol in Serbian factories. The main goals of introducing the concept of sugar and bioethanol coproduction would be efficient use of available resources for the production of energy, reduction of greenhouse gases emission, decreased dependence on import and creation of new jobs. Besides that, it would provide flexibility in terms of variation of produced quantities of sugar and ethanol, depending on the conditions prevailing on the market. 相似文献
404.
405.
Aleksandar R. Zeradjanin Angel A. TopalovSerhiy Cherevko Gareth P. Keeley 《International Journal of Hydrogen Energy》2014
An integral part of the concept of sustainable development and a serious challenge to be addressed is the demanding and costly disposal of the hazardous waste chemicals and/or overproduced chemicals remaining after various production cycles in the chemical industry. For example, the recently reported overproduction of sulfuric acid in China can affect base metal production rates. In this context the consideration of new technologies that can avoid environmental damage or even introduce an economically feasible framework for the utilization of hazardous waste chemicals becomes appealing. 相似文献
406.
A new microcell prediction model for mobile radio environment is presented in this paper. The popular support vector machine algorithm is used as an optimizing tool to build a model. In order to validate the model quality, extensive electric field strength measurements were carried out in the city of Belgrade, for two different test transmitter locations. The analysis of the model has shown that proposed model is fast, accurate (on the order of the local mean measurements uncertainty), reliable, and suitable for computer implementation. 相似文献
407.
This work presents a novel method for the visual servoing control problem based on second-order conic optimization. Special cases of the proposed method provide similar results as those obtained by the position-based and image-based visual servoing methods. The goal in our approach is to minimize both the end-effector trajectory in the Cartesian space and image feature trajectories simultaneously. For this purpose, a series of second-order conic optimization problems is solved. Each problem starts from the current camera pose and finds the camera velocity as well as the next camera pose such that (1) the next camera pose is as close as possible to the line connecting the initial and desired camera poses, and (2) the next feature points are as close as possible to the corresponding lines connecting the initial and desired feature points. To validate our approach, we provide simulations and experimental results for several different camera configurations. 相似文献
408.
Aleksandra Djorić Aleksandar Atanasković Marko Živanović 《International Journal of Electronics》2013,100(12):1904-1918
This paper represents, for the first time, the linearisation method of RF power amplifiers, which is based on using the second- and fourth-order nonlinear signals shaped by digital signal processing in a baseband domain. The linearisation signals are generated by the second- and fourth-order nonlinear modifications of the baseband signal in the proposed manners. The composite second- and fourth-order linearisation signals modulate carrier second harmonics, and the modulated signals are then driven to the gate and drain of the amplifier transistor. The linearisation effects of the proposed method are evaluated on a single stage power amplifier for the simulated QAM and OFDM digitally modulated signals at diverse input power levels up to the 1 dB compression point. Moreover, the FPGA implementation of a system for the generation and processing of the fundamental signal, and the second-order linearisation signals is presented in the paper, and the proposed technique is verified for the generated QAM signal. In addition, the linearisation of the two-way asymmetrical Doherty amplifier is performed in the experiment by using software defined radio platforms for synthesising the fundamental signal and the second-order linearisation signals. 相似文献
409.
Shizhao Xiong Yangyang Liu Piotr Jankowski Qiao Liu Florian Nitze Kai Xie Jiangxuan Song Aleksandar Matic 《Advanced functional materials》2020,30(22)
NASCION‐type Li conductors have great potential to bring high capacity solid‐state batteries to realization, related to its properties such as high ionic conductivity, stability under ambient conditions, wide electrochemical stability window, and inexpensive production. However, their chemical and thermal instability toward metallic lithium (Li) has severely hindered attempts to utilize Li as anode material in NASCION‐based battery systems. In this work, it is shown how a tailored multifunctional interlayer between the solid electrolyte and Li anode can successfully address the interfacial issues. This interlayer is designed by creating a quasi‐solid‐state paste in which the functionalities of LAGP (Li1.5Al0.5Ge1.5(PO4)3) nanoparticles and an ionic liquid (IL) electrolyte are combined. In a solid‐sate cell, the LAGP‐IL interlayer separates the Li metal from bulk LAGP and creates a chemically stable interface with low resistance (≈5 Ω cm2) and efficiently prevents thermal runaway at elevated temperatures (300 °C). Solid‐state cells designed with the interlayer can be operated at high current densities, 1 mA cm?2, and enable high rate capability with high safety. Here developed strategy provides a generic path to design interlayers for solid‐state Li metal batteries. 相似文献
410.
Summary The time dependence of reaggregation of sodium alginate (SA) after following the shear-induced deaggregation of the aggregates (egg-box like microgel structures) at filtering through neutral 0.20 m filters has been found. The aggregation of SA in solution prior to filtering was induced by addition 0.1 mM Ca2+ ions. For SA at concentration of 1mg/ml and room temperature, the reaggregation process is finished after four minutes from the end of the filtration of 3.5 cm3 of the solution with rate of filtration of 1 cm3/min. The reaggregation phenomenon is simply explained by diffusional driven processes of calcium ion – SA electrostatic interactions. 相似文献