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91.
Orhan Ozcelik Ali Sari Mehmet Altunsoy Selin Hokerek Neslihan Unal 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2016,38(10):1435-1447
In this study, geochemical behavior of elements is investigated in 25 coal samples collected at 10 locations of ?ahinli coaliferous units at southeast of Ayd?n, Turkey. In all the samples, X-ray powder diffraction and inductively coupled plasma mass spectrometry analyses were performed and element and mineral compositions were determined. Total organic carbon (TOC) values of coals are between 14.6 and 37.7 wt% with average of 28.5 wt%. Samples are composed of quartz, calcite, feldspar, dolomite, mica, gypsum, and salt minerals which are accompanied by illite-, kaolinite-, and smectite-type clay minerals. Comparison of average element contents of world coals and studied samples yields that K > Fe > As > U > Cs > Y > Er > Al > Th > Rb > Yb > W > Tb > Dy > Lu > Ce > Sm > La > Ho > Si > Nd > Gd > Tm > Eu > Nb > Pr > Pb > Sn > Ni > Cu > Ga > Ta > Sb > Zr > Cd > V > Zn > Co > Mo > P > Hf > Ba are found to be enriched, while Mn > Be > Ca > Sr > Bi > Mg are found to be depleted. Statistically elements are correlated with TOC. 相似文献
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In this paper, novel approaches for wind speed data generation using Mycielski algorithm are developed and presented. To show the accuracy of developed approaches, we used three‐year collected wind speed data belonging to deliberately selected two different regions of Turkey (Izmir and Kayseri) to generate artificial wind speed data. The data belonging to the first two years are used for training, whereas the remaining one‐year data are used for testing and accuracy comparison purposes. The concept of distinct synthetic data production with correlation‐wise and distribution‐wise similar statistical properties constitutes the main idea of the proposed methods for a successful artificial wind speed generation. Generated data are compared with test data for both regions in the sense of basic statistics, Weibull distribution parameters, transition probabilities, spectral densities, and autocorrelation functions; and are also compared with the data generated by the classical first‐order Markov chains method. Results indicate that the accuracy and realistic behavior of the proposed method is superior to the classical method in the literature. Comparisons and results are discussed in detail. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
94.
Black carrots (BCs) are a rich source of stable anthocyanins (ACNs). The purpose of this study was to evaluate the effects of clarification and pasteurisation on ACNs of black carrot juice (BCJ). Monomeric ACNs, ACN profile and percent polymeric colour were determined during processing of BCJ. While depectinisation and bentonite treatments resulted in 7% and 20% increases in monomeric ACN content of BCJ, respectively, gelatine–kieselsol treatment and pasteurisation resulted in 10% and 3–16% reduction. Percent polymeric colour decreased after clarification, but substantially increased in samples subjected to heat. ACNs of BCJ samples were identified by HPLC–MS. Unclarified BCJ contained cyanidin-3-galactoside-xyloside-glucoside-ferulic acid as the major ACN, followed by cyanidin-3-galactoside-xyloside-glucoside-coumaric acid, and cyanidin-3-galactoside-xyloside-glucoside. After depectinisation, two more ACNs (cyanidin-3-galactoside-xyloside and cyanidin-3-galactoside-xyloside-glucoside-sinapic acid) were also identified. These results indicated that depectinisation and bentonite treatment had positive effect on the colour of BCJ, while gelatin–kieselsol treatment and pasteurisation had negative effect. 相似文献
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96.
Congestion is a challenging problem in wireless sensor networks, which exacerbates with the high volume of data traffic imposed by video applications such as video surveillance and target tracking. Deployment of multiple sinks is a candidate solution for congestion and is also promising in terms of reliability and energy-efficiency. In order to gain the maximum benefit from multiple sinks, it is essential to distribute the load among them evenly. In this paper, we propose a cross layer geographic forwarding scheme MLBRF (Multi-Sink Load Balanced Reliable Forwarding) which aims to provide reliable and energy efficient video delivery in a multi-sinked sensor network for target tracking. In order to provide load balancing among the sinks, MLBRF proposes a sink selection mechanism based on fuzzy logic for the frame forwarding which evaluates the traffic density in the direction of each sink by combining two dynamic criteria which are the number of contenders and the buffer occupancy levels in the neighborhood with the static distance criterion. The performance of the fuzzy sink selection mechanism is compared using simulation with various sink selection mechanisms. The results show that MLBRF gains the maximum benefit from deploying multiple sinks in terms of reliability, latency and energy efficiency by using the proposed fuzzy sink selection mechanism. 相似文献
97.
Mehmet Ayvaz Safiye İpek Ayvaz İbrahim Aydin 《International Journal of Hydrogen Energy》2018,43(44):20271-20283
Consumption of the fossil fuels causes greenhouse gas effect and environmental pollution, which are two basic problems of our age. As a result of this problem, clean and renewable alternative energy sources are beginning to replace fossil fuels. Nowadays, the use of hydrogen energy, which is one of the clean energy, is increasing in transportation and industrial areas. Increasing of hydrogen energy usage, scientists are attempting to solve the many safety problems (such as fire, burst, impact and hydrogen embrittlement) that can occur during the storage and consumption of hydrogen energy. In this study, during the event of fire, the safety of metallic Type I pressure hydrogen storage tanks is investigated by using a novel approach. In this new approach, the mechanical strength drops of the tank materials that is related with temperature rising are added to the safety calculations. In the study, 6061 T6 aluminum and SS 316L stainless steel alloys were used as hydrogen tank material. The safety of hydrogen tanks modelled using these alloys was investigated under different temperature conditions (22, 100, 200 and 300 °C) and internal pressure (15, 20 and 25 MPa). 相似文献
98.
Graft copolymers from commercial chlorinated polypropylene via Cu(0)‐mediated atom transfer radical polymerization 下载免费PDF全文
Commercially available chlorinated polypropylene has been used as a macroinitiator for the Cu(0)‐mediated atom transfer radical polymerization of methyl methacrylate and tert‐butyl acrylate to obtain well‐defined graft copolymers. The relatively narrow molecular weight distribution in the graft copolymers and linear kinetic plots indicated the controlled nature of the copolymerization reactions. Both Fourier transform infrared and 1H NMR studies confirmed that the graft reactions had taken place successfully. After graft copolymer formation, tert‐butyl groups of poly(tert‐butyl acrylate) side chains were completely converted into poly(acrylic acid) chains to afford corresponding amphiphilic graft copolymers. © 2016 Society of Chemical Industry 相似文献
99.
Dissolved oxygen is the amount of oxygen dissolved in water corresponding to an important water quality parameter in rivers, streams, and lakes. Hydraulic structures can increase dissolved oxygen levels by creating turbulent conditions where small air bubbles are carried into the bulk of the flow. A gated conduit is a hydraulic structure that can be used efficiently in aeration and oxygen transfer. The subatmospheric pressure between the upstream and downstream of the gate is the reason for the air injection. Ozone is an unstable gas comprised of three oxygen atoms, and it can be used for water treatment. Ozone is thermodynamically unstable and spontaneously reverts back into oxygen. Ozone has been widely accepted as an effective disinfectant and a chemical oxidant. In this study a series of experiments was conducted to determine the ozone injection performance of circular conduits. Results showed that circular conduits are very effective for ozone injection. 相似文献
100.
Abuzer Çelekli Mehmet Yavuzatmaca Hüseyin Bozkurt 《Journal of hazardous materials》2010,173(1-3):123-129
The adsorption of copper ions on Spirulina platensis was studied as a function of contact time, initial metal ion concentration, and initial pH regimes. Characterization of this adsorbent was confirmed by FTIR spectrum. Modified Gompertz and Logistic models have not been previously applied for the adsorption of copper. Logistic was the best model to describe experimental kinetic data. This adsorption could be explained by the intra-particle diffusion, which was composed of more than one sorption processes. Langmuir, Freundlich, and Redlich–Peterson were fitted to equilibrium data models. According to values of error functions and correlation coefficient, the Langmuir and Redlich–Peterson models were more appropriate to describe the adsorption of copper ions on S. platensis. The monolayer maximum adsorption capacity of copper ions was determined as 67.93 mg g?1. Results indicated that this adsorbent had a great potential for removing of copper as an eco-friendly process. 相似文献