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K.R. Murali 《Materials Science in Semiconductor Processing》2010,13(3):193-198
CdSexTe1?x films were deposited by the slurry coating technique using CdSexTe1?x powders synthesized in the laboratory. X-ray diffraction studies indicated the formation of a hexagonal phase. From EDAX compositional analysis, the individual concentrations of Se and Te in the films were estimated. Analysis of the optical data indicate the band gap to vary from 1.44 to 1.68 eV as the value of ‘x’ changes from 0 to 1. XPS analysis was also carried out on the films. The films were used as photoanodes in polysulphide electrolyte and it was observed that the films with composition CdSe0.6Te0.4 exhibited the maximum photoactivity. The Mott–Schottky plot indicated an n-type behaviour. Spectral response measurements were made and the electrodes exhibited a quantum efficiency of 0.6. 相似文献
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Debabrata Rautaray Kaustav Sinha Sudhakar R. Sainkar Renu Pasricha Neela R. Pavaskar Murali Sastry 《Journal of the American Ceramic Society》2005,88(1):24-27
This paper describes the growth of barium chromate (BaCrO4 ) nanocrystallites within thermally evaporated thin films of stearic acid (StA) and sodium bis-2-ethylhexyl-sulfosuccinate by a process of Ba2+ ion entrapment followed by in situ reaction with CrO4 2− ions. Dense spherical assemblies of BaCrO4 nanocrystallites of very uniform size (∼50 nm) were obtained within the two different host matrices. The spherical assemblies were composed of smaller (ca. 5–10 nm size) BaCrO4 crystals indicating that efficient size control over crystal size may be exercised by the matrix. Contact angle measurements of the BaCrO4 –StA and BaCrO4 –sodium bis-2-ethylhexyl-sulfosuccinate films indicated that they were hydrophobic, thus pointing to the possible role of hydrophobic interaction between the StA and sodium bis-2-ethylhexyl-sulfosuccinate monolayer-covered BaCrO4 crystals in the assembly process. 相似文献
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Use of micelles in photogalvanic cell for solar energy conversion and storage: Azur A-glucose system
Sodium lauryl sulphate (NaLS), tetradecyl trimethyl ammonium bromide (TTAB) and Brij-35 were used in a photogalvanic cell containing azur A as a photosensitizer and glucose as a reductant for solar energy conversion and storage. The photopotential and photocurrent generated by the cell in the presence of NaLS were 811.0 mV and 1470 μA, respectively. The effect of variation of the concentrations of the surfactants on the electrical output, the fill factor, the conversion efficiency and the performance of the cell in the dark was studied in detail. 相似文献
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Ruoyu Su Ramachandran Venkatesan Cheng Li 《Wireless Communications and Mobile Computing》2016,16(9):1158-1172
In addition to the requirements of the terrestrial sensor network where performance metrics such as throughput and packet delivery delay are often emphasized, energy efficiency becomes an even more significant and challenging issue in underwater acoustic sensor networks, especially when long‐term deployment is required. In this paper, we tackle the problem of energy conservation in underwater acoustic sensor networks for long‐term marine monitoring applications. We propose an asynchronous wake‐up scheme based on combinatorial designs to minimize the working duty cycle of sensor nodes. We prove that network connectivity can be properly maintained using such a design even with a reduced duty cycle. We study the utilization ratio of the sink node and the scalability of the network using multiple sink nodes. Simulation results show that the proposed asynchronous wake‐up scheme can effectively reduce the energy consumption for idle listening and can outperform other cyclic difference set‐based wake‐up schemes. More significantly, high performance is achieved without sacrificing network connectivity. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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K.A. Dubey C.V. Chaudhari S.K. Suman N. Raje R.K. Mondal V. Grover S. Murali Y.K. Bhardwaj L. Varshney 《Polymer Composites》2016,37(3):756-762
Flexible lead‐free high energy radiation shielding material was developed through internal compounding. Polymer‐filler interaction, crosslinking density, specific gravity, physicomechanical characteristics, percentage attenuation, and thermal stability of the crosslinked composites were estimated. It was found that even at very high filler loading composites can be crosslinked; however, the crosslinking density was composition dependent and was highest in 10–50 wt% loading range at 100 kGy and 200 kGy. The Nielsen model was applied to understand the micromechanics of the system. Attenuation of gamma radiation from Am241 was not affected by the crosslinking density. Thermal stability of the composites was found to be significantly affected with bismuth oxide loading. POLYM. COMPOS., 37:756–762, 2016. © 2014 Society of Plastics Engineers 相似文献
100.
Experimental studies are carried out on the inclined solar still with baffle plates for enhancing its performance. The baffles placed in the inclined solar still act as a solar collector which helps in increasing the contact time with solar radiation thereby raising the saline water temperature. Experiments are carried out during winter and early summer climate of Chennai, India. Experimental parameters, such as ambient temperature, solar radiation, glass temperature, water temperature and distillate output are recorded. Hourly productivity is found to be higher during sunny days. The estimated production of fresh water through analytical study is 3.50?kg/m2 per day for a minimum mass flow rate of 0.0833?kg/min. The actual experimental yield is 2.793?kg/m2 per day. Also, the inlet saline water temperature affects the yield and the latter is found to be highest at 48.5°C. 相似文献