Li J.,Tongji University |
Ma S.,Tongji University |
Cheng L.,Institute of Geological Experiment of Anhui Province |
Wu Q.,Tongji University
Materials Letters | Year: 2015
Sulfur doped three-dimensional porous carbon materials with specific surface area as high as 2277.79 m2 g-1 are prepared by the carbonization of KOH-pretreated egg yolks and employed as electrode materials for supercapacitor application. The material carbonized at 800°C exhibits maximum specific capacitance of 287.66 F g-1 at a current density of 0.5 A g-1 and still retains a capacitance of 220.37 F g-1 at the high current density of 20 A g-1. This material also shows excellent capacity retention of 97.7% after 2000 cycles at a current density of 2 A g-1. These results indicate that the surface area, pore volume and heteroatom doping could combine together to affect the electrocapacitive performances of the obtained materials as electrodes. © 2014 Elsevier B.V. All rights reserved.
Zhou S.,Tongji University |
Wen M.,Tongji University |
Wang N.,Tongji University |
Wu Q.,Tongji University |
Cheng L.,Institute of Geological Experiment of Anhui Province
Journal of Materials Chemistry | Year: 2012
Uniform NiCo alloy hexagonal nanoplates were synthesized through a formaldehyde molecule controlled growth process. They are investigated as a crystal plane selective dehydrogenation catalyst for potential hydrogen energy applications and visible-light synergistic catalysts for nano-ZnO. The resultant NiCo alloy hexagonal nanoplates exert highly efficient crystal plane selective catalytic activity and long-term stability for the hydrolytic dehydrogenation of aqueous ammonia borane under ambient atmosphere at room temperature. Additionally, they exhibit crystal plane selective visible-light-driven enhanced catalysis enhancement for nano-ZnO towards the degradation of methylene blue solution. These results suggest the importance of the rational design and synthesis of NiCo alloy hexagonal nanoplates for high performance hydrogen energy and visible-light-driven catalysis applications. © The Royal Society of Chemistry 2012.
Liang S.-T.,Institute of Geological Experiment of Anhui Province |
Liu Y.-C.,Institute of Geological Experiment of Anhui Province |
Liu Z.,Institute of Geological Experiment of Anhui Province |
Yang S.,Institute of Geological Experiment of Anhui Province |
And 2 more authors.
Yejin Fenxi/Metallurgical Analysis | Year: 2013
As it's difficult to identify the isomorphous minerals under the microscope, in order to determine the abnormal elements and their positions in the mineral specimens the qualitative scan and distribution analysis of the main elements and the associated elements in such tungsten ores as wolframite ((Fe, Mn) WO4) and scheelite (CaWO4) were conducted with the microanalysis capacity of X-ray fluorescence spectrometer and then in the critical measurement areas at those positions the qualitative analysis was conducted to obtain the contents of the mineral components. Finally the coordination number of each component was calculated, and the ore was denominated according to the theoretical values of the mineral component contents. According to the scanning images of the mineral specimens, the analytical spectral lines, the background points, the energy windows and the measurement modes were selected with emphasis to effectively avoid interference. The overlapping interference, matrix effect and mineralogical effect for spectral lines were carefully studied, and the appropriate calibration methods were selected. The correlation coefficient of the calibration curve for each main measurement component was larger than 0.999. The precision of the quantitative identification method was investigated and the relative standard deviation (RSD, n=12) for each component was less than 4%. The experimental method was applied to the determination of wolframite and scheelite specimens and the quantitative identification results were compared with electron microprobe analysis results. It's found that the relative deviations (RD) of the identification results of the major components of three mineral specimens were less than 4% and the three sets of data were exactly consistent.