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Partially filled polycrystalline p‐type skutterudites of nominal compositions Ybx Co3FeSb12 were synthesized and their thermoelectric properties characterized. The compositions and filling fractions were confirmed with a combination of Rietveld refinement and elemental analysis. The thermoelectric properties were evaluated from 300 K to 810 K. The Seebeck coefficient and resistivity increase while the thermal conductivity decreases with increasing Yb content. A maximum ZT value of 0.85 was obtained at 810 K. This work is part of a continuing effort to enhance the thermoelectric properties of p‐type skutterudites, as this class of materials continues to be of interest for thermoelectrics applications. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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Molecular Diversity - An efficient, mild and environmentally benign protocol has been developed for the synthesis of aminouracil-tethered tri-substituted methane derivatives. The three-component... 相似文献
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Potential of synthetic genetic network, Repressilator, to work as logical computing unit is observed. It is shown that two variables of gene network yield simultaneously, the basic AND or OR gate with their complementary NAND or NOR gate, with the variation of the internal parameter of the system. This allows the gene network to work as a strong candidate for parallel computing. Stability or robustness of gates is also checked in noisy background. 相似文献
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Pooja Devi Ashok Kumar Jain M. Someshwer Rao Bhishm Kumar 《Isotopes in environmental and health studies》2013,49(3):426-438
A continuous and reliable time series data of the stable isotopic composition of atmospheric moisture is an important requirement for the wider applicability of isotope mass balance methods in atmospheric and water balance studies. This requires routine sampling of atmospheric moisture by an appropriate technique and analysis of moisture for its isotopic composition. We have, therefore, used a much simpler method based on an isotope mass balance approach to derive the isotopic composition of atmospheric moisture using a class-A drying evaporation pan. We have carried out the study by collecting water samples from a class-A drying evaporation pan and also by collecting atmospheric moisture using the cryogenic trap method at the National Institute of Hydrology, Roorkee, India, during a pre-monsoon period. We compared the isotopic composition of atmospheric moisture obtained by using the class-A drying evaporation pan method with the cryogenic trap method. The results obtained from the evaporation pan water compare well with the cryogenic based method. Thus, the study establishes a cost-effective means of maintaining time series data of the isotopic composition of atmospheric moisture at meteorological observatories. The conclusions drawn in the present study are based on experiments conducted at Roorkee, India, and may be examined at other regions for its general applicability. 相似文献
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Pardeep Singh Pankaj Raizada Anita Sudhaik Pooja Shandilya Pankaj Thakur Shilpi Agarwal Vinod Kumar Gupta 《Journal of Saudi Chemical Society》2019,23(5):586-599
In this work, we have reported synthesis of AgBr/BiOBr photocatalyst supported on graphene (Gr) using facile precipitation method. AgBr/BiOBr/Gr was characterized using various spectral techniques like FESEM, TEM, XRD, FTIR, XPS, Raman and PL analyses. AgBr/BiOBr/Gr had improved visible light absorption. PL studies indicated the reduction in recombination of photogenerated electron hole pair of AGBr/BiOBr/Gr. AFM analysis confirmed the thickness of AGBr/BiOBr/Gr was less than 8.0 nm. The higher dispersibility of photocatalyst was ascertained by Tyndall effect. AgBr/BiOBr/Gr photocatalyst was effectively used for the photodegradation of phenol from simulated water. The phenol degradation process was remarkably influenced by adsorption process. The concurrent adsorption and photocatalytic was effective for degradation of phenol. The phenol was completely mineralized into CO2 and H2O in 6 h. The degradation process followed pseudo first order kinetics. The results confirmed that integration of AgBr/BiOBr with graphene caused an increase in photocatalytic activity due to reduced recombination of photogenerated electron hole pair and electron sink behavior of graphene for photogenerated electrons of BiOBr. AgBr/BiOBr/Gr photocatalyst displayed significant stability and recyclability for ten catalytic cycles. 相似文献
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Pooja Varshney Sarita Afaq Ahmad Saba Beg 《Journal of Physics and Chemistry of Solids》2006,67(11):2305-2309
Electrical conductivity of ZrO2 doped with Pb3O4 has been measured at different temperatures for different molar ratios (x=0, 0.01, 0.02, 0.03, 0.04, 0.05 and 0.06). The conductivity increases due to migration of vacancies, created by doping. The conductivity increases with increase in temperature till 180 °C and thereby decreases due to collapse of the fluorite framework. A second rise in conductivity at higher temperatures beyond 500-618 °C is due to phase transition of ZrO2. DTA and X-ray powder diffraction were carried out for confirming doping effect and transition in ZrO2.The addition of Pb3O4 to ZrO2 shifted the phase transition of ZrO2 due to the interaction between Pb3O4 and ZrO2. 相似文献