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121.
Shipra Jain Jyoti Shah Nainjeet Singh Negi Chhemendra Sharma Ravinder Kumar Kotnala 《国际能源研究杂志》2019,43(9):4743-4755
Recent increase in energy demand and associated environmental degradation concern has triggered more research towards alternative green energy sources. Eco‐friendly energy in facile way has been generated from abundantly available iron oxides using only few microliters of water without any external energy source. Hydroelectric cell (HEC) compatible to environment benign, low cost oxygen‐deficient mesoporous hematite nanoparticles has been used for splitting water molecules spontaneously to generate green electricity. Hematite nanoparticles have been synthesized by coprecipitation method. Chemidissociated hydroxyl group presence on hematite surface has been confirmed by infrared spectroscopy (IR) and X‐ray photoelectron spectroscopy (XPS). Surface oxygen vacancies in nanostructured hematite have been identified by transmission electron microscopy (TEM), XPS, and photoluminescence (PL) measurement. Hematite‐based HEC delivers 30 mA current with 0.92 V emf using approximately 500 μL water. Maximum off‐load output power 27.6 mW delivered by 4.84 cm2 area hematite‐based HEC is 3.52 times higher than reported 7.84 mW power generated by Li‐magnesium ferrite HEC. Electrochemistry of HEC in different irreversible polarization loss regions has been estimated by applying empirical modeling on V‐I polarization curve revealing the reaction and charge transport mechanism of cell. Tafel slope 22.7 mV has been calculated by modeling of activation polarization overvoltage region of 0.11 V. Low activation polarization indicated easy charge/ion diffusion and faster reaction kinetics of Ag/Zn electrode owing to lesser energy barrier at interface. Dissociated H3O+ ions diffuse through surface via proton hopping, while OH? ions migrate through interconnected defective crystallite boundaries resulting into high output cell current. 相似文献
122.
Dissociation of water molecule occurs on octahedrally coordinated unsaturated suface cations and oxygen vacancies created by lithium substitution in magnesium ferrite. Lower synthesis temperature of ferrite has generated nanopores in microstructure. Dissociated hydronium and hydroxyl ions are transported through surface and capillary diffusion in porous ferrite network towards attached Zn and Ag electrodes. Water molecule dissociation ability of nanoporous ferrite has been exploited to develop a green electrical energy cell, which is a combination of material science and electrode chemistry. The innovated cell has been nomenclatured as hydroelectric cell (HEC). When HEC is partially dipped in deionized water, spontaneously hydroxide and hydronium ions are produced by water molecule dissociation. Hydronium ions trapped in nanopores develop enough electric field that further dissociates physisorbed water molecules. Thereby, the process of water molecule dissociation is accelerated in a bigger way to increase ionic current in the cell. Oxidation of Zn electrode by hydroxide ion and reduction of H3O+ at Ag electrode develop voltage and electric current in the cell. The HEC cell of a 17 cm2 area is able to generate a short circuit current of 82 mA and 920 mV emf with a maximum output power of 74 mW, which is three order higher than reported output power 1.4 μW/cm2 produced by water in cement matrix. Hydroelectric cell performance is repetitive, stable and possesses potential to replace traditional ways of generating renewable energy in terms of cost and safety. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
123.
Bitumen extraction from oil sands is carried out in large separation cells using a water-based extraction process. Controlling
the Bitumen-froth and Middlings interface in these cells at an optimum level provides significant economical and environmental
benefits. Traditional sensors are not reliable in estimating this interface level and novel vision-based sensors have been
developed previously to overcome this problem. These sensors estimate the interface level and its confidence for separation
cells with a single sight glass. The confidence value only represents the turbidity of the interface and hence cannot be used
for control decision making in all process conditions. The current work describes an image differencing algorithm for interface
level detection which also facilitates the computation of a confidence estimate that is accurate in most process situations.
The confidence value is computed based on noise statistics, an appropriately chosen edge detection method and a change detection
algorithm. Another significant advantage of the algorithm is that both the interface level and the confidence estimation procedures
can be extended in a straight-forward manner to handle the presence of multiple sight glasses. Off-line results show that
the algorithm accurately detects the interface level in normal process conditions (with high confidence values) and outputs
correct confidence values in other situations with very low false-positive and false-negative error rates. On-line industrial
implementation results show that the vision sensor tracks the interface level very closely and results in significant automation
of plant. 相似文献
124.
Significant improvement for the functional properties of konjac glucomannan based on phase separation
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Qing Huang Honghe Ge Weiping Jin Bakht R. Shah Shuxin Ye Ying Hu Bin Li Yijie Chen 《International Journal of Food Science & Technology》2016,51(11):2396-2405
Konjac glucomannan (KGM) serves as a stabiliser due to its high molecular weight and viscosity. However, these properties limit its addition in food products, especially in drinks. The main aim of this study was to improve the functional properties of KGM by a green and effective method, that is phase separation. It was found that increasing temperature accelerated phase separation of KGM/gum arabic mixture. KGM‐rich phase was characterised and its physical properties were investigated by different methods. Crystal property showed no significant changes after phase separation. Nevertheless, rheological properties indicated that the viscosities of samples after phase separation (FKGM) decreased dramatically. Their emulsifying capacities also improved. Moreover, the differences in molecular rearrangement at the oil–water interface were also studied by using interfacial rheology. These results suggested that FKGM with low viscosity had better interfacial properties, and thus may have potential applications as food ingredients. 相似文献
125.
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127.
Fine bamboo strips (BSs) have been laid on polypropylene (PP) web, stacked, and compression molded to prepare unconsolidated light-weight (0.312 g/cm3) composites. Composite properties are superior compared with jute-based composites and bamboo strips show potential to replace fiberglass or polyurethane in composites. Flexural strength, modulus, offset yield load, and Noise Reduction Coefficient (NR) of the BS–PP composites are 5.8×, 2.9×, 6.5×, and 1.4× higher, respectively, compared to jute–PP composites. Bamboo-based non-consolidated composites with excellent mechanical and sound absorption properties utilizing the methods described in this research provide an opportunity to manufacture functional composites with bio-based materials leading to reduction of environmental pollution and sustainable manufacturing. 相似文献
128.
Characterizing cerebral oxygen metabolism employing oxygen-17 MRI/MRS at high fields 总被引:1,自引:1,他引:0
Ali Gordji-Nejad Klaus Möllenhoff Ana Maria Oros-Peusquens Deepu R. Pillai Nadim Jon Shah 《Magma (New York, N.Y.)》2014,27(1):81-93
This article provides a comprehensive overview of oxygen (17O) magnetic resonance spectroscopy and imaging, including the advantages and challenges offered by the different methods developed thus far. The physiological role and relevance of oxygen, and its participation in aerobic metabolism, are addressed to emphasize the importance of the investigations and the efforts related to these developments. Furthermore, a number of methods employed in the determination of the cerebral metabolic rate of oxygen in neural cells will be presented, focusing primarily on methodologies enabling absolute quantification. 相似文献
129.
Sunil Pandey Ritu Shah Ashmi Mewada Mukeshchand Thakur Goldie Oza Madhuri Sharon 《Journal of materials science. Materials in medicine》2013,24(7):1671-1681
Use of cysteamine hydrochloride (Cys-HCl) protected gold nanorods (GNRs) as efficient carrier of widely used anti-cancer drug doxorubicin using folic acid as navigational molecule is presented in this work. GNRs were found to have excellent drug loading capacity of >97 %. A detailed comprehension of in vitro drug release profile under ideal physiological condition was found to obey 1st order kinetics at pH 6.8, 5.3 and 7.2, an ideal milieu for drug delivery to solid tumours. 相似文献
130.
A. H. Shah M. Basheer Ahamed E. Manikandan R. Chandramohan M. Iydroose 《Journal of Materials Science: Materials in Electronics》2013,24(7):2302-2308
The influences of annealing effects have been explored on the crystallinity, morphology, optical and magnetic properties of Ag–ZnO nanostructures prepared by a simple sol–gel method. X-ray powder diffraction, scanning electron microscope, high resolution transmission electron microscope (HRTEM), vibrating sample magnetometer and photoluminescence spectroscopy (PL) have been used to characterize the crystal structures, surface morphology, magnetic and optical properties of the pure ZnO and Ag–ZnO nanostructures respectively. The synthesized Ag–ZnO nanostructures are found to have hexagonal wurtzite crystal structures and their grain size increases while lattice strain decreases on annealing. From HRTEM observation, it is found that the annealed samples show nanorod like structures with Ag nanoparticles (NPs) embedded on the surface. Due to annealing effect, Ag–ZnO shows higher saturation magnetization at room temperature. 相似文献