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Hybrid composites La2‐xCoxCuO4 (x = 0, 0.1, 0.2, and 0.3) are prepared using one‐step simple hydrothermal route as electrodes for supercapacitors. The effect of varying cobalt content on morphological, structural, and electrochemical properties has been explored using X‐ray diffraction, scanning electron microscopy, and cyclic voltammetry, respectively. The structural parameters obtained by X‐ray diffraction showed tetragonal phase of hybrid composite without any evident impurity phases. The analysis of morphological properties suggested a strong correlation with electrochemical properties, for instance, a relationship between fabric porous structures and electrochemically active sites for redox reactions and intercalation/de‐intercalation processes. The hybrid composite electrodes demonstrated high specific capacitance of the order of 1304 F/g at 10 mV/s scan rate and exhibited decreasing trend on increasing scan rate. Hybrid composites were also tested for their ability as an electrode of high performance supercapacitors in different aqueous electrolytes, i. e, KOH, H2SO4, and Na2SO4 to optimize the best compatible electrolyte. The composite electrode material showed excellent cyclic stability and 98% capacitance retention for 1 A/g after 2000 cycles. The remarkable performance of hybrid composite electrode entails its potential for commercial applications of supercapacitors.  相似文献   
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Today’s world, tetracycline hydrochloride (TC) is considered as a Compounds of Emerging Concern (CECs). Metal-organic frameworks MOFs with a microporous structure and holding larger pores indicating potential applications in the fields of environmental purification. Recently, carbon aerogel (CA) has also aroused great interest due to its larger specific surface area, low density, thermal stability, and non-toxicity. Herein, MIL-100(Fe) was synthesized under low temperature and combined with Fe3O4 and CA, respectively. The obtained MIL-100(Fe), MIL-100(Fe)@Fe3O4, MIL-100(Fe)@CA and MIL-100(Fe)@Fe3O4/CA were investigated as a photocatalyst for removal of TC from the water. The results indicated that the MIL-100(Fe)@Fe3O4/CA degrade TC up to 85%, which is much higher than MIL-100(Fe)@Fe3O4 (c.a. 42%), due to its high surface area 389?m2?g?1, smaller pore size and pore volume 2.4?nm and 0.319?m3?g?1, high separation of electron and hole, and lower band gap of 1.76?eV. The coupling of CA with MIL-100(Fe)@Fe3O4 considerably accelerate the transfer of photo-generated charge carriers and enhanced 1.6 times the performance of MIL-100(Fe)@Fe3O4. Furthermore, the stability and recyclability were enhanced due to the addition of Fe3O4, facilitating the environmentally friendly water purification processes.  相似文献   
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Size and shape dependencies of phase diagrams of the Ising nanofilms and nanotubes on the honeycomb lattice are investigated by means of probabilistic cellular automata simulation based on Glauber algorithm. The values of reduced critical temperature, K c = k B T c/J (where k B and J are the Boltzmann constant and nearest-neighbor coupling, respectively), for both nanofilms and nanotubes, are obtained at the different sizes of the lattices and the dependency of K c to the number of layers is studied. By increasing the number of layers K c increases but for number of layer more than 8, the critical temperature increases very slowly. We have shown that between two isotropic nanotubes with the same number of spins, the ones with greater diameter (more spins on the edge) have larger critical temperature. For equal size of lattices, the obtained values of K c for nanotube are greater than the nanofilm, but for large sizes, this difference disappears.  相似文献   
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This research evaluated the effect of drought on total and individual polyphenol contents as well as the antioxidant activities of cumin (Cuminum cyminum L.) seeds of 2 geographic origins, Tunisia (TCS) and India (ICS). Plants were treated with different levels of water deficit: control. Our results indicated that, in both varieties, moderate water deficit (MWD) improved the number of umbels per plant as well as the number of umbellets per umbel and the seed yield, in comparison to the control, but it decreased under severe water deficit (SWD). Besides, total phenolic contents were higher in the treated seeds and drought increased the level of total and individual polyphenols. This increase was appreciably more important in TCS than in ICS. Moreover, antioxidant activities of the extracts were determined by 4 different test systems, namely 2,2-diphenyl-1-picrylhydrazyl, β-carotene/linoleic acid chelating, and reducing power assays, and showed that treated seeds exhibited the highest activity, for both TCS and ICS.  相似文献   
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The energy crisis has reached to an alarming situation due to increase in population. To overcome the shortfall of energy, solid oxide fuel cell (SOFC) being cheap, clean, and efficient renewable energy source is getting attention for electricity generation. Out of the three main components as anode, electrolyte, and cathode; anode/fuel electrode is an important component of SOFC because it allows the flow of electrons via external circuit to cathode generating the electric current and hence requires high electrical conductivity. In this review, anode materials synthesized until now are reviewed and by careful analysis categorized on the basis of operating temperature, conductivity, electrode polarization resistance, and structure. This comparison and categorization will provide selection criteria for state‐of‐the‐art and highly efficient anode materials for SOFC. In addition, the synthesis methods have been reviewed on the basis of their pros and cons, which will further facilitate the researchers to select the best synthesis method so as to get optimized properties of materials.  相似文献   
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The dates production is usually accompanied by considerable loss of fruit byproducts. The chemical analysis showed that ‘Deglet Nour’ discarded flesh is rich in soluble sugars (79.8% ± 0.8%) and fibers (12.3% ± 0.4%). A processing approach was implemented to permit the production of biohydrogen from the flesh and biogas from the crude fiber fraction after soluble sugars extraction. This approach showed interesting results since the obtained biochemical hydrogen potential and the maximum methane yield were 292 mL H2/gVS initial and 235 mL CH4/gVS fibers respectively. Parallelly, the “hot water” soluble sugar fraction (date syrup) was of interest for agro-alimentary applications and showed a high sucrose, glucose and fructose content of 33.5%, 11.8% and 13.17% respectively. This study presents a proof of concept allowing an efficient sustainable energetic conversion of the date by-products biomass to biohydrogen via dark fermentation or to soluble sugars fraction and biogas via a biorefinery approach.  相似文献   
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Aiming at increasing the nutritional value and sensory quality of bread, we assessed the enrichment of white flour with different levels of powdered cinnamon and pomegranate peel, through rheological, nutritional, aromatic, textural and sensory analyses. These extra ingredients were chosen for their richness in bioactive compounds, and they differently affected bread quality. In relation to raw flour, introduced ingredients slightly decreased moisture and protein content, while increasing ash, fibre and radical scavenging activity, which can be attributed to the sharing of aromatic compounds by cinnamon and pomegranate peel during the bread making process. When cinnamon was incorporated at 1%, the content of all furan derivatives was reduced up to 1/4 of initial value, 2-pentyl furan totally disappeared, and furfuryl alcohol was reduced to 2.1%. Despite enriched bread’s texture was slightly worse, it was still acceptable in sensory tests, as 150 interviewed naive consumers preferred the new product over the control.  相似文献   
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