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991.
Xin Cui Xinxin Zhang Mu Yang Yanhui Feng Hongyi Gao Wenbo Luo 《Journal of Thermal Analysis and Calorimetry》2013,113(2):693-701
COREX is the primary process in the current smelting reduction method. The process has strict coal quality standards. Combustion processes of coal used in the COREX operating system were analyzed using a synchronous thermogravimetric analyzer combined with a mass spectrometer. The microcosmic structure and macerals were observed by an electronic scanning microscope. The qualitative and quantitative determinations of oxygen functional groups, such as phenolic hydroxyl, carboxyl, carbonyl, and methoxy groups were detected by the Fourier Transform Infrared spectrometer (FT-IR) and through chemical analysis methods. In addition, the evolution of the chemical structure and transformation mechanism of organic oxygen functional groups during COREX coal combustion have been thoroughly investigated. This study proposes a new coal-requirement index system and coal blending method, which will increase the expansion of coal selection and decrease the overall usage of coal during COREX. 相似文献
992.
Bingjing Ye Huyuan Feng Jihua Zhao Jian Fang Weiguo Shen 《Journal of Thermal Analysis and Calorimetry》2013,111(3):1731-1736
Microcalorimetric techniques had been used to study the influence of different physicochemical parameters on microbial growth in different permafrosts on the Tibetan plateau. The total heat evolution of the permafrost samples amended with glucose, Q T , the values of microbial growth rate constant, k, and the heat output power, P t , were calculated from the power–time (P–t) curves. It is observed that the same coverage vegetation show similar P–t curves, which strongly suggest that the permafrost microorganisms of the homology vegetation coverage have similar structures of community. Furthermore, the vegetation degradation turns out to have significant influence, that is, the better the status of vegetation is, the higher the values of k, CFU and Q T are. 相似文献
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Jia‐Xing Zhao Dr. Yan‐Zhen Zheng Xin‐Hong Lu Prof. Jian‐Feng Chen Prof. Xia Tao Prof. Weilie Zhou 《Chemphyschem》2013,14(9):1977-1984
We report two novel types of hierarchically structured iodine‐doped ZnO (I? ZnO)‐based dye‐sensitized solar cells (DSCs) using indoline D205 and the ruthenium complex N719 as sensitizers. It was found that iodine doping boosts the efficiencies of D205 I? ZnO and N719 I? ZnO DSCs with an enhancement of 20.3 and 17.9 %, respectively, compared to the undoped versions. Transient absorption spectra demonstrated that iodine doping impels an increase in the decay time of I? ZnO, favoring enhanced exciton life. Mott–Schottky analysis results indicated a negative shift of the flat‐band potential (Vfb) of ZnO, caused by iodine doping, and this shift correlated with the enhancement of the open circuit voltage (Voc). To reveal the effect of iodine doping on the effective separation of e?‐h+ pairs which is responsible for cell efficiency, direct visualization of light‐induced changes in the surface potential between I? ZnO particles and dye molecules were traced by Kelvin probe force microscopy. We found that potential changes of iodine‐doped ZnO films by irradiation were above one hundred millivolts and thus significantly greater. In order to correlate enhanced cell performance with iodine doping, electrochemical impedance spectroscopy, incident‐photon‐current efficiency, and cyclic voltammetry investigations on I? ZnO cells were carried out. The results revealed several favorable features of I? ZnO cells, that is, longer electron lifetime, lower charge‐transfer resistance, stronger peak current, and extended visible light harvest, all of which serve to promote cell performance. 相似文献
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