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621.
构建长江经济带多区域投入产出表,并基于Tapio脱钩模型和结构分解分析,从生产侧和消费侧视角研究2002~2012年长江经济带各省市分行业碳排放与经济增长的脱钩效应及影响因素.在此基础上,研究长江经济带各省市投资、消费和出口引致的隐含碳排放与经济增长的关系.结果发现:从省市层面来看,与2002~2007年相比,2007~2012年各省市生产侧碳排放的脱钩状态有所好转,均呈现为弱脱钩.消费侧方面,2007~2012年期间5省市(江苏省、安徽省、湖北省、重庆市和贵州省)为扩张连接,云南省为扩张负脱钩,可以发现生产侧视角下存在高估脱钩状态的现象.从各省市分行业来看,中上游地区制造业在2002~2007年期间消费侧的碳排放多呈现为弱脱钩,到了2007~2012年消费侧的脱钩状态总体上较不理想.建筑业具有类似情况.2007~2012年各省市的电力行业在两视角下均实现脱钩.从消费、投资和出口的角度来看,2007~2012年下游地区出口和投资的脱钩状态趋于好转.中上游地区投资的脱钩状态趋于恶化,出口的脱钩状态好转不明显. 相似文献
622.
采用小波分解(WD)将济南市科干所监测站PM_(2.5)浓度的一维时间序列(2013年1月1日—2017年8月15日)分解为高维信息,获得了该监测站附近PM_(2.5)浓度的时频变化特征,重点分析了PM_(2.5)的随机性和趋势性问题.然后构建了基于小波分解的多级残差修正的最小二乘支持向量回归预测模型(AMLRC-WLSSVR),结果发现,该模型能够很好地对济南市PM_(2.5)浓度做出预测,特别是针对重污染天气的预测有很好的精度.为了避免预测结果的不确定性问题,提出了一种基于方差估计给出预测值置信区间上界的方法,同时,有效弥补了单点预测的不稳定性及预测精度不足的缺点,该方法能够为实际空气污染预警提供技术支持. 相似文献
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624.
Thermal decomposition kinetic of liquid organic peroxides 总被引:3,自引:0,他引:3
Xin-Rui Li Hiroshi Koseki 《Journal of Loss Prevention in the Process Industries》2005,18(4-6):460-464
This study demonstrates the application of isothermal calorimeter for investigating the thermal decomposition of several liquid organic peroxides, such as t-Butyl peroxy acetate (TBPA), Di-tert butyl peroxide (DTBP), and Cumene hydroperoxide (CHP). The decomposition mechanism and kinetic can be identified from case to case. TBPA and DTBP undergo first order reaction, whereas CHP occurs autocatalysis. Accurate kinetic can be assessed on the basis of discerning these various schemes of given samples. Consequently, the thermal runaway or reactive hazards potential of organic peroxides can be determined, for instance as a self accelerating decomposition temperature (SADT). 相似文献
625.
William F. James Robert H. Kennedy William E. Sham Richard K. Myers 《Journal of the American Water Resources Association》1988,24(4):831-837
ABSTRACT: The impoundment of Richard B. Russell Lake resulted in the inundation of 3490 ha of forested area or 33 percent of the total area of the lake. Estimates of the total inundated leaf litter biomass were combined with a leaf litter decomposition study to determine the nutrient load and dissolved oxygen demand to the reservoir. Hickory leaf bags broke down most rapidly at the 3-m and 28-rn depths, followed by short-needle pine, white oak, a hardwood litter mixture, beech, and red oak. Leaf bags incubated at the 3-m depth exhibited significantly higher breakdown rates than those at the 28-m depth for most leaf types, due to differences in dissolved oxygen and temperature. Respiration rates of litter were also higher at the 3-m depth. Most leaf types accumulated nitrogen and phosphorus and lost organic carbon after an initial leaching period. Richard B. Russell Lake exhibited extensive anoxia and the buildup of total organic carbon, nitrogen, and phosphorus during summer stratification. Leaf litter breakdown accounted for 64 percent of the organic carbon increase but acted as a sink for nitrogen and phosphorus. The dissolved oxygen demand of the litter accounted for over 50 percent of the demand incurred in the lake. 相似文献
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628.
The catalytic effect of alumina on the destruction of toluene, benzene, acetone and methanol, in DC pulsed corona discharge reactor was studied. In the presence of alumina the inlet concentration of the VOCs was varied from ~5×10-6mol/L to ~80×10-6mol/L, and their decomposition efficiency (conversion %) was found to be 99%—80% for toluene, 99%—97% for benzene, 95%—92% for acetone, and 72%—85% for methanol. Corresponding decomposition in the absence of alumina was 90%—38% for toluene, 89%—57% for benzene, 42%—30% for acetone, and 47%—19% for methanol. Feed gas flow rate was 400 cm3/min and power reading from DC source was 7.4 W in all of the experiments. Alumina also shifted the CO/CO2 ratio in the by products in favor of CO2. Ozone concentration at the reactor outlet was higher in the presence of alumina. Enhancement in VOCs decomposition by alumina was explained on the basis of higher concentration of ozone and its precursor atomic oxygen [O] . Decomposition efficiency (conversion %) for individual compounds was found to be inversely proportional to the ionization potential of the compound, under identical conditions. Double DC high voltage sources pulse generator was tested and found to improve VOCs decomposition compared with the conventional single DC high voltage source. 相似文献
629.
Problems related to biological decomposition of wood and volumes of mycogenic emission of carbon dioxide and carbon in forests of Western Siberia are considered. Annual C-CO2 emission in the region reaches 31 million tons of carbon, which is equivalent to 116 million tons of carbon dioxide. With respect to the volume of emission, natural zones may be arranged in the following descending series: southern taiga (38%), middle taiga (29%), subtaiga (16%), forest-steppe (10%), northern taiga (6%), and forest-tundra (1%). 相似文献
630.