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101.
An overview of the environmental,economic, and material developments of the solar and wind sources coupled with the energy storage systems 下载免费PDF全文
There is a constant growth in energy consumption and consequently energy generation around the world. During the recent decades, renewable energy sources took heed of scientists and policy makers as a remedy for substituting traditional sources. Wind and photovoltaic (PV) are the least reliable sources because of their dependence on wind speed and irradiance and therefore their intermittent nature. Energy storage systems are usually coupled with these sources to increase the reliability of the hybrid system. Environmental effects are one of the biggest concerns associated with the renewable energy sources. This study summarizes the last and most important environmental and economic analysis of a grid‐connected hybrid network consisting of wind turbine, PV panels, and energy storage systems. Focusing on environmental aspects, this paper reviews land efficiency, shaded analysis of wind turbines and PV panels, greenhouse gas emission, wastes of wind turbine and PV panels' components, fossil fuel consumption, wildlife, sensitive ecosystems, health benefits, and so on. A cost analysis of the energy generated by a hybrid system has been discussed. Furthermore, this study reviews the latest technologies for materials that have been used for solar PV manufacturing. This paper can help to make a right decision considering all aspects of installing a hybrid system. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
102.
This study aims to investigate the permanent deformation behavior of asphalt concrete reinforced by nylon fibers. Nylon fibers (12 mm length) have been added to a typical asphalt concrete at different percentages of 0.05, 0.1, 0.15, 0.2, 0.25, and 0.3% (based on total weight of mixture), and the permanent deformation behavior of the mixtures have been investigated by dynamic creep tests at different stress levels of 200 and 400 kPa, and different temperatures of 40, 50, and 60 °C on the mixtures. A three-stage model (developed by Zhou et al.) has been used for modeling the creep curve of the mixtures and determining the flow number and creep strain slope of the mixtures, which are used to describe the permanent deformation of asphaltic mixtures. The parameters of the models were determined in MATLAB using an algorithm established by Zhou et al. The results showed that the mixture reinforced by 0.1% of nylon fibers has the highest resistance to permanent deformation. The three-stage model was well fitted with the dynamic creep test results of the mixtures. The results also showed that the mixture containing 0.1% of nylon fibers has the lowest creep strain slope and the highest flow number, indicating that this mixture has the highest resistance to permanent deformation. 相似文献
103.
104.
In this study, pumpkin seeds, called as “Ürgüp Sivrisi” and grown in Cappadocia region, were used as plant materials because of high aroma contents. In the supercritical fluid extraction of pumpkin seed oil, the effect of main process parameters as the particle size (250-2360 μm), the volumetric flow rate of supercritical solvent (0.06-0.30 L/h), the operating pressure (20-50 MPa), the operating temperature (40-70 °C), the type of entrainer (ethanol and n-hexane) and those concentrations (0-10 vol.%) on the extraction yield, the oil solubility and the initial extraction rate were investigated. A cross-over effect for the extraction of pumpkin seed oil using supercritical CO2 was determined at the operating pressure of 20-30 MPa. The maximum extraction yield obtained with entrainer free was reached 0.50 g oil/g dry seed at 600-1180 μm, 0.12 L/h, 50 MPa and 70 °C for the operation time of 5 h. The maximum extraction yield obtained with ethanol as an entrainer in the experiments was reached 0.54 g oil/g dry seed at the conditions of 600-1180 μm, 0.12 L/h, 30 MPa, 40 °C and 8 vol.% for the operating time of 2 h. The oil compositions were determined by gas chromatography analysis and the results showed that the compositions of pumpkin seed oil which were obtained by means of organic solvent extraction and supercritical fluid extraction were similar. The average oil compositions determined as 9.3 (±0.43)% palmitic acid, 7.5 (±0.6)% stearic acid, 32.3 (±0.6)% oleic acid, 48.1 (±0.6)% linoleic acid and 0.7 (±0.3)% linolenic acid. The morphological changes in the seeds were determined by the scanning electron microscopy analysis. 相似文献
105.
Hasan Yildirim Mansur Sümer Veysel Akyüncü Emrah Gürbüz 《Construction and Building Materials》2011,25(6):2939-2947
Fly ashes are obtained from thermal power plants and they are pozzolanic materials, which can act as partial replacement material for both portland cement and fine aggregate. With their economical advantages and potential for improving fresh and hardened concrete performance, they have some benefits for using in concrete industry. In this study, the objective was to find the efficiency factors of Turkish C and F-type fly ashes and to compare their properties. Three different cement dosages were used (260, 320, 400 kg/m3), two different ratios (10% and 17%) of cement reduced from the control concretes and three different ratios (depending on cement reduction ratio) of fly ash were added into the mixtures. At the ages of 28 and 90 days, compressive strength, modulus of elasticity and ultrasound velocity tests were carried out. From the compressive strength results, the k efficiency factors of C and F-type fly ashes were obtained. As a result, it is seen that efficiency factors of the concrete produced by the replacement of F and C type fly ashes with cement increase with the increase in cement dosage and concrete age. 相似文献
106.
In this study, L-cystein modified bentonite-cellulose (cellu/cys-bent) nanocomposite was synthesized and characterized by XRD, FTIR, SEM with EDS, TGA, and TEM techniques. In order to optimize the process the effect of various operational parameters such as pH, adsorbent dosage, contact time, and temperature were also investigated. The adsorption experiments were carried out in initial concentrations range of 20-100 mg L?1and the adsorbent affinity for metal ions was found to be in order of Cu2+ > Pb2+ > Cd2+. The optimum pH for adsorption of Cu2+ and Cd2+ was observed at 5 while for Pb2+ it was pH 6. Based on the Langmuir model, the maximum adsorption capacity of Cu2+, Pb2+, and Cd2+ at 50?C was found to be 32.36, 18.52, and 16.12 mg g?1, respectively. The Langmuir isotherm and pseudo-second order model were found to be better fitted than the other isotherms and kinetic models. The results of thermodynamic parameters confirmed the process to be endothermic and spontaneous in nature. 相似文献
107.
Mohammad Tajul Islam Shahadat Hossain Khan Md Mahadi Hasan 《Coloration Technology》2016,132(3):255-264
An attempt was made to print cotton fabric with pigments using a new thickening agent based on Aloe vera gel in combination with sodium alginate. The results were compared with the standard conventional printing recipe containing synthetic thickener, and a favourable effect of Aloe vera introduction was achieved. The results show that the properties of the printed fabric (sharpness, colour yield, overall fastness properties, softness, and water vapour transmission) are dependent on the percentage of Aloe vera gel in the thickener combination, the concentration of printing auxiliaries, and the curing conditions. Optimal printing properties were achieved by using a printing paste containing 80% Aloe vera/20% sodium alginate (700 g kg?1), pigment (50 g kg?1), binder (145 g kg?1), fixer (10 g kg?1), and ammonium sulfate (5 g kg?1), followed by drying at 85 °C for 5 min and curing at 150 °C for 3 min. The sample printed with the new recipe showed superior rubbing fastness and handle properties, with a slightly lower colour yield, when compared with the sample printed with synthetic thickener. Finally, economic issues arising from synthetic thickener substitution are highlighted. 相似文献
108.
Shaikh A. Ali Shamsuddeen A. Haladu Mohammad A. J. Mazumder Hasan A. Al-Muallem 《Iranian Polymer Journal》2016,25(9):747-756
An aqueous solution of diallylammonium salts (CH2 = CHCH2)2NH+(CH2)3A? having A? as: CO2 ? (I), PO3H2 Cl? (II) and SO3 ? (III) in 1:1:1 mol ratio underwent ammonium persulfate-initiated ter cyclopolymerization to yield pH-responsive zwitterionic polymer IV with random placements of the monomers in the same ratio. During dialysis, PO3H2Cl? of the incorporated monomer units of II upon depletion of HCl became PO3H?. Likewise, azobisisobutyronitrile-initiated cyclopolymerization of I, II, III, and SO2 in a mole ratio of 1:1:1:3 provided pH-responsive tetrapolymer V in over 90 % yield with random and alternative placements of I–III and SO2 units, respectively, in the same ratio as the feed. Polyzwitterions (PZs) IV and V were insoluble in salt-free water but soluble in the presence of salts. The critical salt concentrations required to promote water solubility of PZ IV were determined to be 0.356 M NaCl, 0.237 M NaBr and 0.128 M NaI, whereas for PZ V the corresponding values were found to be 2.25, 1.26 and 0.862 M, respectively. PZs IV and V were converted into anionic polyelectrolytes VI and VII upon basification with NaOH. The viscosity and antiscalant behaviors of VI and VII were examined. The polymers demonstrated remarkable scale inhibition efficacies; at a dose of 10 ppm, both IV (+NaOH) and V (+NaOH) delayed the precipitation of CaSO4 from its supersaturated solution up to 920 and over 4000 min, respectively. For a small concentration of 5 ppm of polymer V, a scale inhibition of 100 % over 100 min verified it to be a potential effective antiscalant additive in reverse osmosis plants. 相似文献
109.
Nana Achile Alomayri Thamer Salman Venyite Paul Kaze Rodrigue C. Assaedi Hasan Suliman Nobouassia Christelle Bewa Sontia Jordan Valdès Metekong Ngouné Jean Kamseu Elie Leonelli Cristina 《SILICON》2022,14(1):263-274
Silicon - The synthesis, mechanical behaviour, and microstructure of metakaolin-based geopolymer mortar reinforced with quartz sand are presented in this investigation. Fine sand (quartz sand)... 相似文献
110.
Hasan Kouchakzadeh Seyed Abbas Shojaosadati Fazel Shokri 《Chemical Engineering Research and Design》2014
Herein, the poorly water-soluble drug, Tamoxifen (Tmx), was loaded in the amphipathic matrix of human serum albumin (HSA) nanoparticles by a modified desolvation method. In order to enhance the drug loading (DL) and drug entrapment efficiency (DEE) (<2% and 10%, respectively), ultrasonication of Tmx-HSA mixture was performed prior to desolvation process. Tmx loading and entrapment efficiency were optimized by employment of the response surface methodology (RSM)-central composite design (CCD) of experiments. Under the optimum conditions of 1.59 mg Tmx/ml concentration, 7.76 pH and 5 h incubation of HSA-Tmx, the DL of 6.7% and DEE of 74% are achievable. Particles with the average size of 195 nm, zeta potential of −21 mV and polydispersity index of 0.09 were produced under these conditions. A more sustained Tmx release behavior was observed from polyethylene glycol (PEG) conjugated nanoparticles in comparison to the non-PEGylated ones. The short-term stability investigation showed no alteration in physicochemical properties of nanoparticles at 4 and 37 °C, but small increase in nanoparticles size was observed after three months of storage at room temperature. This is the first report for efficient production of a Tmx delivery system based on HSA nanoparticles. 相似文献