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排序方式: 共有1236条查询结果,搜索用时 31 毫秒
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Vishnu Vijaykumar Gurudeo Nirala Dharmendra Yadav Upendra Kumar Shail Upadhyay 《国际能源研究杂志》2020,44(6):4652-4663
Nanocrystalline powders of co-doped ceria oxides Ce0.85La0.10Sr0.05O2-δ (CLSO) and Ce0.85Gda0.10Sr0.05O2-δ (CGSO) have been synthesized by auto combustion method at 100°C using sucrose as fuel. Thermal analysis (TGA/DSC) of as-prepared powders indicated calcination above 400°C to remove organic residue. The average grain size of the pellets sintered at 1200°C for 4 hours is 436 and 683 nm for CLSO and CGSO, respectively. The electrical conductivity of the sintered samples was determined by impedance measurements in the temperature range 300°C to 600°C and the frequency range 20 Hz to 2 MHz. At 600°C, the total electrical conductivity (σt) of CGSO is 6.78 × 10−3 S cm−1, 2.5 times higher than 2.72 × 10−3 S cm−1 of CLSO. Further, it is found that the value of grain boundaries blocking factor (αgb) of CGSO is 0.47 which is 30% lesser than 0.68 of CLSO at 600°C. The higher value of electrical conductivity of CGSO as compared to CLSO is attributed to the lesser blocking effect of grain boundaries, smaller lattice distortion and denser microstructure of CGSO as compared to CLSO. The electrical conductivity of synthesized samples has been compared with the electrical conductivity of similar compositions of co-doped CeO2 oxides. Our study indicated that the sintering temperature, and hence, the morphology of sintered samples has a significant role in determining the electrical conductivity. The presence of oxygen vacancies in the synthesized samples is experimentally supported by using UV-visible spectroscopy, Raman spectroscopy, and thermal analysis techniques. 相似文献
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Yadav Ashish Mohan Tripathi Kuldeep Narayan Sharma S. C. 《The Journal of supercomputing》2022,78(3):4236-4260
The Journal of Supercomputing - With the rapid increase in the functionality of IoT applications, the services provided by edge/IoT devices have surged in the recent past. Fog computing is gaining... 相似文献
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Dolly Yadav Rajesh K. Yadav Abhishek Kumar No-Joong Park Jae Young Kim Jin-Ook Baeg 《应用聚合物科学杂志》2020,137(14):48536
C60-based polymeric systems have been constantly anticipated for sustainable solar energy conversion. Reported, herein is a C60 polymer film as visible light active photocatalyst for efficient and selective reduction of CO2 for the first time. The C60 polymer photocatalyst is synthesized via covalent coupling of C60 monomer units consisting of tetra substituted C60-pyrene conjugates through spacer groups. The synthesized C60 polymer photocatalyst possesses an extended network of well-defined repeating monomer units with good stability and visible light-induced photocatalytic activity. The enhanced visible light harvesting ability of C60 polymer photocatalyst reasonably yields it with higher catalytic ability than its monomer unit. The C60 polymer film photocatalyst upon coupling with the biocatalyst carries out highly selective visible light driven reduction of CO2 to HCOOH (239.46 μmol). The tandem way of incorporating C60 into visible light active polymeric films for continuous use may be highly rewarding for their extended photocatalytic activity for solar fuel production from CO2. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48536. 相似文献
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The micellization behavior of amphiphiles is a well-analyzed physicochemical phenomenon, which can be easily influenced by various parameters such as pressure, temperature, and the presence of different additives. Inorganic salts are able to affect the thermodynamic and surface properties of amphiphiles significantly. The effect of a series of salts as additives namely lithium chloride (LiCl), potassium chloride (KCl), sodium chloride (NaCl), sodium bromide (NaBr), and sodium iodide (NaI) on interfacial chemical characteristics of the surface-active ionic liquid (SAIL) 1-dodecyl-3-methylimidazolium chloride [C12mim][Cl] in aqueous solution were examined through conductance, surface tension, fluorescence, 1H NMR, and dynamic light scattering measurements. The interfacial and thermodynamic parameters of all investigated SAIL-salt systems were evaluated from surface tension and conductance measurements, respectively. A detailed analysis of the microenvironment of the micelles and the size of the micelles was done using 1H NMR and dynamic light scattering measurements. 相似文献
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Coal is the most abundant energy source, and around 40% of the world's electricity is produced by coal combustion. The emission generated through it put a constraint on power production by coal combustion. There is a need to reduce the emissions generated through it to utilize the enormous energy of coal for power production. Detailed understanding of various aspects of coal combustion is required to reduce the emissions from coal‐fired furnaces. The aim of present paper is to review various aspects of pulverized coal combustion such as oxy‐fuel combustion, co‐combustion of coal and biomass, emissions from pulverized coal furnaces, ash formation and deposition, and carbon capture and sequestration (CCS) technologies to outline the progress made in these aspects. Both experimental and numerical aspects are included in this review. This review also discusses the thermodynamic aspects of the combustion process. Furthermore, the effect of various submodels such as devolatilization models, char combustion models, radiation models, and turbulent models on the process of pulverized coal combustion has been investigated in this paper. 相似文献