排序方式: 共有19条查询结果,搜索用时 62 毫秒
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以粉煤灰(FA)为原料,采用水热晶化一步法制备了Na P1型沸石(ZFA),对合成产物的结构进行了表征,并采用阳离子表面活性剂十六烷基三甲基溴化铵(CTAB)对其进行改性。通过静态吸附实验,研究了改性后Na P1型沸石(MZFA)对水溶液中甲基橙的吸附特性,从动力学角度探讨了吸附机理。结果表明,在所研究的浓度条件下,改性Na P1型沸石对甲基橙的吸附符合Langmuir等温吸附方程,在25℃时,静态饱和吸附量(Qm)为64.76 mg/g。动力学分析表明,改性Na P1型沸石对溶液中甲基橙的吸附符合准二级动力学模型。 相似文献
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城市生命线网络的地震动力可靠度是生命线工程地震风险和抗震韧性评估的重要指标。城市生命线网络地震动力可靠度的计算方法包括以蒙特卡洛方法为代表的模拟方法和以推广的递推分解算法为代表的非模拟方法,因为后者能够给出生命线网络的主要失效模式,因而它比模拟方法更为先进。但是,由于存在高维Gumbel Copula参数无法估计的问题,目前推广的递推分解算法还不能计算大型生命线网络(组成生命线网络系统的结构或设备数目大于60)的地震动力可靠度。为解决这个问题,提出了高维Gumbel Copula参数的拟合估计公式,将其嵌入推广的递推分解算法,形成了大型生命线网络地震动力可靠度的计算方法。某实际220 kV变电站设备网络地震动力可靠度的计算和分析,说明了此方法的使用过程、适用范围和有效性。 相似文献
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Ali Shahzad Xu Yueyue Ma Xiangcheng Henchiri Malak Cai Tie Ren Xiaolong Zhang Jiahua Jia Zhikuan 《Environmental science and pollution research international》2019,26(6):5539-5553
Environmental Science and Pollution Research - Determining the effect of ridge-furrow cultivation mode on 13C carbon isotope discrimination, photosynthetic capacity, and leaf gas exchange... 相似文献
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Weihua Zhou Xiangcheng Yuan Aimin Long Hui Huang Weizhong Yue 《Environmental monitoring and assessment》2014,186(3):1705-1718
The subtropical Hong Kong (HK) waters are located at the eastern side of the Pearl River Estuary. Monthly changes of water quality, including nutrients, dissolved oxygen (DO), and phytoplankton biomass (Chl-a) were routinely investigated in 2003 by the Hong Kong Environmental Protection Department in three contrasting waters of HK with different prevailing hydrodynamic processes. The western, eastern, and southern waters were mainly dominated by nutrient-replete Pearl River discharge, the nutrient-poor coastal/shelf oceanic waters, and mixtures of estuarine and coastal seawater and sewage effluent of Hong Kong, respectively. Acting in response, the water quality in these three contrasting areas showed apparently spatial–temporal variation pattern. Nutrients usually decreased along western waters to eastern waters. In the dry season, the water column was strongly mixed by monsoon winds and tidal currents, which resulted in relatively low Chl-a (<5 μg l?1) and high bottom DO (>4 mg l?1), suggesting that mixing enhanced the buffering capacity of eutrophication in HK waters. However, in the wet season, surface Chl-a was generally >10 μg l?1 in southern waters in summer due to halocline and thermohaline stratification, adequate nutrients, and light availability. Although summer hypoxia (DO <2 mg l?1) was episodically observed near sewage effluent site and in southern waters induced by vertical stratification, the eutrophication impacts in HK waters were not as severe as expected owing to P limitation and short water residence time in the wet season. 相似文献
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Ali Shahzad Xu Yueyue Ma Xiangcheng Jia Qianmin Jia Zhikuan 《Environmental science and pollution research international》2021,28(22):27666-27680
Environmental Science and Pollution Research - Understanding the greenhouse gas emissions mechanism from the agricultural soils is essential to reach an agricultural system with a lower impact on... 相似文献