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Chen Yujun Guan Bin Wu Xingze Guo Jiangfeng Ma Zeren Zhang Jinhe Jiang Xing Bao Shibo Cao Yiyan Yin Chengdong Ai Di Chen Yuxuan Lin He Huang Zhen 《Environmental science and pollution research international》2023,30(5):11246-11271
Environmental Science and Pollution Research - In recent years, with global climate change, the utilization of carbon dioxide as a resource has become an important goal of human society to achieve... 相似文献
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针对岩质边坡稳定性评价的模糊性与多指标性特点,采用模糊层次分析法确定Ⅰ、Ⅱ级指标权重,提高了0.1~0.9标度法所确定权重的客观性并克服了单一性,且避免了同一对指标比较时的不一致性,量化了不连续性基础指标。引入功效系数法对不同类型的基础指标进行功效系数值归一化求解,结合功效系数值与Ⅰ、Ⅱ级指标权重向量计算得出总功效系数值,据总功效系数值大小划分稳定性级别。在模糊层次分析法基础上,运用功效系数法对永吉岩质边坡进行稳定性评价、分级的结果与实际调查情况相符。证明该方法对岩质边坡稳定性分级具有很好的适用性与可靠性。 相似文献
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LI Xiaolin ZHANG Yuanxun TAN Mingguang LIU Jiangfeng BAO Liangman ZHANG Guilin LI Yan IIDA Atsuo 《环境科学学报(英文版)》2009,21(8):1118-1124
The Pb-monitoring program was extended for 6 years from 2002 to 2007 at 17 representative urban sites (6 traffic, 5 industrial, and 6 residential sites), and 3 suburban sites to assess the lead pollution in fine particulate matter (PM2.5) after phasing out leaded gasoline in Shanghai. Compared with Pb levels reported in other places, the Pb pollution in Shanghai is still serious after phasing out leaded gasoline, which remains at high concentration range (213–176 ng/m3) in PM2.5 in winter. Significant spati... 相似文献
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作为全球气候治理的重要手段,碳排放交易制度受到了广泛的关注与讨论。基于此,本文采用我国2010-2016年城市面板数据,运用非参数方法构建方向性环境距离函数测算了2009-2015年城市减排的机会成本,计算结果显示,试点地区与非试点地区的碳排放的机会成本整体表现为上升的趋势,且试点地区的碳排放的机会成本总体低于非试点地区。在测算城市减排机会成本的基础上,运用双重差分法来检验碳排放交易制度的有效性。经检验发现:碳排放交易制度有利于降低城市减排的机会成本,然而由于碳排放交易制度还存在碳排放权初始分配制度缺失、碳排放交易制度的定价机制扭曲等问题,因此其对降低城市减排的机会成本作用较小,并且进一步通过对政策时间趋势的分析得出政策效应随时间推移而逐渐减弱。 相似文献
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采用模拟污染物的同位素示踪技术研究HTO(氚水)在茶树-土壤模拟生态系统中的迁移规律。测定了植物和土壤样品中两种形态氚(自由水氚和结合态氚)的比活度,并应用具有相互交换的双库室开系统模型确定了茶和土壤分室的拟合方程。结果表明:引入土壤中的HTO,不仅在系统积分室间转移和分配,而且迅速向系统外扩散;HTO中的氚以自由水氚和结合态氚形式存在于茶树中,以吸湿性水氚和结晶水氚存在于土壤,其中自由水氚(或吸湿性不氚)远大于结合态氚(或结晶水氚);对实验数据进行回归分析得;茶树植株中的总氚比活度Ct(t)=314.09(e^-0.0569t-e^-0.3777t),土壤中的总氚比活度Cs(t)=136.73e^-0.3777t 112.22e^-0.0569t。 相似文献
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Re-Os法能够对金属硫化物矿物直接进行同位素定年,并可以根据矿物的Os同位素初始比值探讨成矿物质来源。它的研究对象还包括黑色页岩和洋底含金属沉积物等。普通Os法可以用于铂族元素矿物定年和成矿物源区的讨论。近年由常规Re-Os法衍生的Os-Os法有可能避免前者在定年技术方面的一些困难。Re-Os同位素体系为成矿年代学研究提供了广阔的前景。 相似文献
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Distribution and migration of 95Zr in a tea plant/soil system 总被引:3,自引:0,他引:3
(95)Zr is a primary radionuclide in the radioactive liquid efflux from a pressurized water reactor and one of the main radionuclides released after nuclear accidents. The fission yield of (95)Zr is as high as 6.2%, however, its environmental behavior has not been well documented. An experiment was conducted to evaluate the accumulation and distribution of (95)Zr in a tea plant/soil system. (95)Zr was accumulated primarily in the trunk of tea plants after being taken up from the soil. The radioactivity concentration of (95)Zr in the trunk increased slowly with time, then it reached a dynamic equilibrium 14 days after application. The radioactivity concentration of (95)Zr in the other parts of the tea plant was very low; only slighter greater than the detection limit. The results indicated that (95)Zr was not readily translocated in the tea plant. About 98.9% of applied (95)Zr was found to concentrate in the upper 5 cm layer after being sprayed onto the soil surface. The results indicated that (95)Zr could not readily move downwards with percolating water due to strong adsorption to surface soil. 相似文献
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