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随着经济的发展,消防救援队伍承担的任务越来越繁重.重大灾害事故的发生,对消防战勤保障方面提出了更高的要求.文章主要从消防战勤保障的主要任务职能、消防战勤的任务分类以及消防战勤保障体系建设存在的问题与建议等几个方面进行了详细的阐述,以期消防战勤保障得到更好的发展. 相似文献
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Yinghui Sun Guojie Zhang Haizhu Cheng Jun Liu Guoqiang Li 《International Journal of Hydrogen Energy》2021,46(1):531-542
The mechanism and kinetic features of dry reforming with methane (DRM) over Ca promoted 1Co–1Ce/AC-N catalyst was investigated. The mechanistic pathway studies have conducted by FTIR and XPS analysis, structure-activity correlations demonstrated the CH4 and CO2 could adsorb on catalyst active sites and generate intermediate CHx, OH and CHxO, continue to generate CO and H2 and then desorbed from active sites. Moreover, CH4 could also oxidized by Ce4+ and CO2 reduced by Ce3+, the same content of Ce4+ and Ce3+ on promoted catalyst greatly improved the reaction rate. The kinetic of dry reforming with methane was examined for temperature between 650 and 850 at 800 °C. The research was carried out by changing the CH4/CO2 ratios between 0.3 and 3.0. The obtained experiment data were fitted by three typical kinetic models (Power Law, Eley-Rideal and Langmuir-Hinshelwood), the fitting results demonstrated that the best prediction of reforming rates can provided by Langmuir-Hinshelwood model for the reaction temperatures between 650 and 800 °C. Moreover, activation energies of methane and carbon dioxide consumption were ?117 and ?47 kJ/mol, indicating that much higher energy barrier is needed for methane activation compared to carbon dioxide. 相似文献
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Hong Xiao Dexin Fang Yingjun Wang Yinlong Xiao Lin Luo Zhang Cheng Xiaohong Zhang Hong Peng 《International Journal of Hydrogen Energy》2021,46(35):18401-18411
Nymphoides peltatum (NP) is exploited as a novel feedstock for biomethane production via anaerobic co-digestion with waste sludge (WS). Batch experiments are conducted under mesophilic condition at NP/WS of 1/3, 2/2, 3/1, 0/4 and 4/0 based on volatile solids (VS). Prior to anaerobic digestion (AD), NP undergoes only natural drying and grinding. The maximum net cumulative methane yield (265.16 mL CH4·g VSadded?1) and the highest gross VS removal rate (56.12%) are obtained at NP/WS of 1/3. The kinetic analysis by the modified Gompertz model fit hinted that 28 days is adequate for methane recovery and co-digestion significantly accelerates the digestion rate. Synergetic effect is corroborated to exist in co-digestion due to amiable conditions in term of total ammonia nitrogen, free ammonia, pH, volatile fatty acids and total alkalinity. High-throughput 16S rRNA pyrosequencing reveals that Bacteroidetes, Firmicutes, Methanosarcina and Methanosaeta are conducive to AD of NP. 相似文献
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Multimedia Tools and Applications - Owing to efficient machine recognition, QR codes have been widely used in many aspects such as information management, electronic identity and mobile payment.... 相似文献