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81.
以γ-Al2O3为载体,以MnxCe1-xO2为催化活性组分,采用浸渍法制备了一系列负载型MnxCe1-xO2/γ-Al2O3催化剂(x=0、0.2、0.4、0.6、0.8、0.9、1),在固定床反应器中评价了催化剂对甲苯的催化燃烧性能。结果表明,MnxCe1-xO2/γ-Al2O3催化剂的催化活性与催化剂的焙烧温度、活性组分MnxCe1-xO2的负载量以及Mn、Ce摩尔比有显著关系,其中焙烧温度550℃、负载量为20%、Mn、Ce摩尔比为4:1时,即MnxCe1-xO2/γ-Al2O3催化剂对甲苯的催化性能最佳,反应温度为180℃时,甲苯的转化率达到95%。并在连续100h的稳定性操作后,催化剂的活性基本无变化。采用XRD、BET以及SEM等分析测试手段对催化剂的结构以及表面进行了表征。 相似文献
82.
Jeff Joireman Heather Barnes Truelove Blythe Duell 《Journal of environmental psychology》2010,30(4):358-367
It is generally acknowledged that global warming is occurring, yet estimates of future climate change vary widely. Given this uncertainty, when asked about climate change, it is likely that people’s judgments may be affected by heuristics and accessible schemas. Three studies evaluated this proposition. Study 1 revealed a significant positive correlation between the outdoor temperature and beliefs in global warming. Study 2 showed that people were more likely to believe in global warming when they had first been primed with heat-related cognitions. Study 3 demonstrated that people were more likely to believe in global warming and more willing to pay to reduce global warming when they had first been exposed to a high vs. a low anchor for future increases in temperature. Together, results reveal that beliefs about global warming (and willingness to take actions to reduce global warming) are influenced by heuristics and accessible schemas. Several practical implications are discussed. 相似文献
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针对垃圾焚烧炉床层内垃圾燃烧过程复杂性及影响垃圾燃烧效率因素多的问题,运用数值仿真方法对某垃圾焚烧炉床层垃圾燃烧进行了模拟,获得了垃圾质量流失速率、水分蒸发速率、挥发分释放速率、焦炭燃烧速率和烟气的温度;并在50~1 000 Nm3/min范围内改变一次风流量,获得了床层质量流失比值、过剩空气系数和烟气中各组分的质量百分比含量。仿真结果显示,一次风流量取值517.47~6`32.09 Nm3/min时燃烧效率较高;炉排两端区域的一次风流量在50~75 Nm3/min时,可以使垃圾床表面平均温度明显提高,而且还可以提高燃烧效率,同时减少供风总量,节约能源与动力资源。本研究对优化设计垃圾焚烧炉,提高床层内垃圾的燃烧效率有一定参考价值。 相似文献
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V.S. Yaliwal P.G. Tewari S.Y. Adaganti 《International Journal of Sustainable Engineering》2014,7(3):269-282
Renewable and alternative fuels have numerous advantages compared with fossil fuels as they are renewable and biodegradable and provide food and energy security and foreign exchange savings besides addressing environmental concerns and socio-economic issues (Yaliwal et al. 2013. International Journal of Sustainable Engineering, doi:10.1080/19397038.2013.801530. Zhu et al. 2011a, Applied Thermal Engineering 31 (14–15): 2271–2278; Zhu et al. 2011b, Fuel 90: 1743-1750; Banapurmath, Tewari, and Hosmath 2008, Renewable Energy 33: 2007-2018; Banapurmath 2009, “Performance, Combustion and Emission Characteristics of a Single Cylinder Direct Injection CI Engine Operated on Dual Fuel Mode Using Honge Oil and Producer Gas.” PhD thesis, 1–195; Banapurmath et al. 2011, Waste and Biomass Valorization 2: 1–11). In this context, the main objective of the present work is to study methods of biofuel production such as Honge oil methyl ester (HOME) using a conventional transesterification process and bioethanol from the Calliandra calothyrsus shrub using a new pretreatment method known as hydrothermal explosion. Further, experimental investigations were carried out on a single-cylinder, four-stroke, direct-injection stationary diesel engine operating in a dual-fuel mode using HOME, bioethanol and producer gas combinations to determine its performance, combustion and emission characteristics. The performance of the dual-fuel engine was analyzed at optimized engine conditions. HOME-Bioethanol (BE) blends such as HOME+ 5% bioethanol (BE5), HOME+ 10% bioethanol (BE10) and HOME+ 15% bioethanol (BE15) were prepared by adding bioethanol to HOME (on volume basis) in different proportions ranging from 5 to 15% with an increment of 5%. In this present work, the effect of different BE blends on the performance of producer gas fuelled dual fuel engine was studied. Experimental investigation on dual fuel engine using BE5-Producer gas operation resulted in up to 4–9% increased brake thermal efficiency with decreased hydrocarbon (HC), carbon monoxide (CO) and marginally increased nitric oxide (NOx) emission levels compared to HOME-Producer gas, BE10-producer gas and BE15-producer gas mode of operation. However, it was observed that, the overall performance of BE-producer gas operation was found to be lower compared to diesel-producer gas operation. 相似文献
88.
通过收集整理我国大陆显著地震灾害事件与社会经济发展的相关资料,分析讨论不同经济体制下地震灾害对经济社会发展、产业结构调整等方面的影响,并对地震灾后恢复重建提出对策建议。 相似文献
89.
采用场发射带能谱扫描电镜(FESEM/EDS)法分析北京怀柔地区PM10与秸秆燃烧排放颗粒的形貌特征和成分差异.结果显示:秸秆燃烧后排放颗粒物多为大粒径颗粒,成分上都含S、Cl和K元素.含有生物质燃烧标志元素K的PM10颗粒物多为含Si、Al和Na元素的燃煤飞灰和矿物颗粒,与秸秆燃烧排放颗粒组成化学元素差异明显.据此推... 相似文献
90.
基于物元模型的煤自燃危险性分析 总被引:4,自引:2,他引:2
为探索判断煤自燃的危险性新方法,在煤低温氧化试验的基础上,基于可拓理论构建了煤自燃危险性熵权和经验权的物元综合分析模型。采用该方法对4个不同煤样低温氧化试验数据进行自燃危险性分析,得出各煤样自燃危险性的等级及差异程度,并提出相应的防范对策。结果表明:4号煤样比其他煤样更具自燃危险性,需要重点防范。该方法的预测结果与实际情况相吻合。 相似文献