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801.
以拜耳法生产氧化铝产生的赤泥为捕集剂,对CO2进行捕集,考察了液固比、反应温度、搅拌速率、CO2流量对单位CO2捕集量(以每克赤泥捕集的CO2质量计)和赤泥脱碱率(以钠去除率计)的影响。实验结果表明:在液固比为7#x02236;1、反应温度为30℃、搅拌转速为500r/min、CO2流量为200mL/min的最佳实验条件下,最大单位CO2捕集量为0.0263g/g,赤泥的脱碱率可达到42.43%。赤泥具有较强的捕集CO2的能力,因此,利用固体废弃物赤泥吸收工业废气中的CO2可以达到以废治废的目的。 相似文献
802.
西湖区区级以上绿色社区50%的覆盖率与城镇化趋势和生态文明建设的高目标还不相适应。与省市绿色社区指标相比,区级指标倾向于公众参与和居民自治,建议从区域环境质量、节能减排、生态文化、"三产"等方面进行补充,并提出量化指标、设置否决指标、动态管理和复查退出机制、绿色示范工程、环境认证管理及碳汇林试点等对策。 相似文献
803.
The rapid development of parks and ecotourism in China has attracted worldwide attention, not only for the beauty of the landscape
that the parks are protecting but also for their abundant and often unique biodiversity. However, in some areas, the development
of ecotourism has actually led to the degradation of local ecological, economic, and social systems. Using National Forest
Parks for demonstration, this article analyzes the current political, institutional, legal, environmental, and economic issues
concerning National Parks in China, and examines their potential future development. Although the intention of National Park
systems in China is to raise environmental quality, and to protect biodiversity and social livelihoods, their success has
varied. Future success will be measured by their capacity to reduce poverty, to promote long-term rehabilitation of wildlife
habitats, and to simultaneously protect Chinese culture and biodiversity. 相似文献
804.
MF-UF组合工艺处理再生纸废水的实验研究 总被引:2,自引:1,他引:1
针对再生纸废水体系,采用0.2 μm陶瓷微滤膜 (MF)与截留分子量为50 000 Dalton的疏水性PS有机超滤膜 (UF)组合工艺对再生纸废水进行处理。实验结果表明,此组合工艺对再生纸废水COD的去除率可达到846%,处理的废水达到造纸工业水污染物排放标准;根据再生纸废水的性质对膜清洗再生进行了考察,陶瓷膜及超滤膜通量约分别恢复85%与80%左右。 相似文献
805.
基于物元理论的自然灾害损失等级划分方法 总被引:5,自引:2,他引:3
基于"灾度"概念及其改进算法,结合物元理论,提出了自然灾害损失等级划分的可拓学算法,建立了基于物元理论的自然灾害损失等级划分模型,将物元分析方法应用于自然灾害损失等级划分,作为灾害损失等级评估方法的一种补充,并与之前算法互为验证.不仅论证了物元理论应用于灾害等级划分的可行性,阐述了自然灾害损失评估物元模型的算法过程,而且利用该模型正确评估了2008年中国南方冰冻灾害的损失等级.经过反复验证,证实了该方法的科学性,同时提出了该模型尚存在的细节问题,如灾度上限的取值,权重确定的方法等问题,以便于更好的完善该模型算法. 相似文献
806.
Kyosuke Onishi Tetsuyuki Ueyama Toshifumi Matsuoka Dai Nobuoka Hideki Saito Hiroyuki Azuma Ziqiu Xue 《International Journal of Greenhouse Gas Control》2009,3(3):311-321
A pilot-scale experiment for carbon dioxide (CO2) sequestration was undertaken at the Nagaoka test field in Japan. Time-lapse crosswell seismic tomography was conducted to detect and monitor the movement of CO2 injected into an aquifer. We applied difference analysis with data normalization (DADN) to the time-lapse data to eliminate false images that were apparent in a conventionally processed difference section. Conventional difference analysis calculates travel-time delays after inversion, whereas the DADN method calculates them from raw travel-time records before inversion. Thus, fewer errors are generated with the DADN method compared to a conventional inversion analysis. We applied the DADN method to time-lapse tomography data recorded before and after the injection of CO2 and computed the velocity variation in a subsurface section, which clearly showed the distribution of CO2 flooding within a high permeability zone in the aquifer and showed no CO2 leakage into the caprock. Our results also show the maximum velocity decrease as a result of CO2 injection was about 9%, which is close to the results obtained in laboratory experiments. Finally, numerical simulations were inverted to test the effectiveness of the conventional and DADN methods in dealing with noise. These tests showed that the DADN method effectively reduces unique coherent noise for particular receiver and source combinations. We concluded that the DADN method provides useful data for monitoring the flow of CO2 sequestered in underground aquifers. 相似文献
807.
The accumulation of perfluorinated compounds (PFCs) in the sera of captive wildlife species Bengal tigers (Panthera tigris tigris) and African lions (Panthera leo Linnaeus) from Harbin Wildlife Park, Heilongjiang Province, in China were analyzed by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Perfluorooctanesulfonate (PFOS) was the predominant contaminant with a mean serum concentration of 1.18 ng mL(-1) in tigers and 2.69 ng mL(-1) in lions. Perfluorononanoic acid (PFNA) was the second most prevalent contaminant in both species. The composition profiles of the tested PFCs differed between tigers and lions, and the percentages of perfluorooctanoic acid (PFOA) were greater in lions than in tigers, indicating different exposures and/or metabolic capabilities between the two species. Assessments of the risk of PFC contamination to the two species were obtained by comparing measured concentrations to points of departure or toxicity reference values (TRVs). Results suggest no risk of PFOS exposure or toxicity for the two species. 相似文献
808.
Since carbon compounds are the main component of dense nonaqueous phase liquids (DNAPLs), the end products of all in situ chemical oxidation (ISCO) will include carbon dioxide. If the production rate of carbon dioxide exceeds the capacity of water to remove the carbon dioxide, degassing will occur. The uncontrolled carbon dioxide gas may change the flow patterns, remobilize the pooled DNAPL, transport DNAPL vapor, and reduce the relative permeability to the aqueous phase. Under high pH buffered conditions, most of the carbon dioxide will be dissolved in water. In this study, potassium permanganate oxidation of tetrachloroethylene (PCE) was conducted using a sodium carbonate buffered solution (1 g/L, pH = 10.6 ± 0.1) at three different temperatures (5, 10, and 20°C) and three potassium permanganate concentrations (0.2, 1, and 5 g/L). Extensive kinetic studies suggest that the overall oxidation is a second‐order reaction and pseudo‐first‐order with respect to PCE and potassium permanganate, respectively. The second‐order rate constant and the activation energy were 0.028 ± 0.001 M?1s?1 at 20°C and 43.9 ± 2.85 kJ/M, respectively. This study provides a base for further experimental and field studies on potassium permanganate oxidation of PCE under natural or artificial high pH buffered conditions. © 2004 Wiley Periodicals, Inc. 相似文献
809.
810.