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941.
采用自动烟气分析,通过试验分析无机膜除尘器的脱硫机理和影响因素,试验结果表明在本试验的工况下无机膜除尘器有2.0%~5.7%的脱硫效率,无机膜除尘器在脱硫的过程中起到固定床反应器的作用,同时蒸汽活化粉尘使其中的碱性物质的释放是无机膜除尘器脱硫的关键.  相似文献   
942.
提出了一种改进的加速试验方法,定义了陪试品和载息因子的概念.这两个概念利用产品在设计上的相似之处,将已有产品的寿命表现过程推到新产品上,从而得到新产品的预估寿命.在此方法中应用灰色系统理论解决了加速寿命试验这类只有几个温度点、少样本、贫信息的寿命预估问题.  相似文献   
943.
烟梗黄原酸酯吸附铜离子性能研究   总被引:1,自引:0,他引:1  
以废烟梗为原料,通过制备烟梗黄原酸酯对废烟梗进行化学改性,并用其吸附Cu^2+。考察了搅拌速度,吸附剂用量,pH,温度,粒度,Cu^2+初始浓度和吸附时间对吸附量的影响,发现各种参数对Cu^2+的吸附都有影响。对于50mg/L的Cu^2+,吸附平衡时间为10min,吸附量为19.30mg/g,Cu^2+去除率可达96%。室温下吸附Cu^2+时,可以用拟二级动力学模型描述。结果表明,化学改性的废烟梗去除Cu^2+具有良好的应用前景。  相似文献   
944.
Environmental Chemistry Letters - Microalgae are photosynthetic cell factories of global interest for fuels, food, feed, bioproducts, carbon sequestration, waste mitigation, and environmental...  相似文献   
945.
Environmental Science and Pollution Research - Since export has a key role in economic growth in terms of national production quantity, export quality can be considered another important factor...  相似文献   
946.

As China’s economy began transitioning from one focused on high-speed growth to one focusing on high-quality development, sustainable green development has become the main goal pursued by the government. This study empirically measures the marginal impact of per capita GDP, technological innovation level, industrial structure, openness, fiscal decentralization, and urbanization level on per capita wastewater discharge in 11 provinces (cities) along the Yangtze River Economic Belt (YREB) from 2008 to 2018 using a quantile model. The key findings were as follows: (1) factors such as the per capita GDP, industrial structure, foreign direct investment, and urbanization in the YREB significantly increased water resource pollution; (2) the quantile model regression results showed that the relationship between economic growth and ecological pollution followed the so-called environmental Kuznets inverted U-curve. Wastewater discharge per capita was low in areas with low per capita GDP, meaning that the ecological environment in these areas was more fragile and that the environmental pollution costs due to economic growth were therefore relatively much higher in these areas; (3) fiscal decentralization significantly reduced water resource pollution in relatively developed areas although the effects in the relatively developing areas were not significant; and (4) the effects of technological innovation on reducing water resource pollution in the YREB were positive but not very significant. The results also confirmed that traditional patterns of economic growth increased water pollution in the YREB. For this reason, the government needs to urgently improve policies—for example, upgrading economic structures, preventing over-urbanization, speeding up technological innovation, introducing environmentally friendly foreign investment, and providing more rewards to best practitioners of environmental governance—that is conducive to the achievement of green ecological development.

  相似文献   
947.
Environmental Science and Pollution Research - In this study, we investigated the impact of the mixed-application with pymetrozine on the behavior (i.e., uptake, translocation, and degradation) of...  相似文献   
948.
Journal of Polymers and the Environment - Extracellular polymeric substances (EPSs) can be defined as renewable, high molecular weight polymeric materials produced by bacteria and microorganisms....  相似文献   
949.
综合考虑舰船装备系统的复杂性和海洋环境的严酷性,提出了一种基于关键产品把控的舰船装备环境适应性设计对策分析方法.该方法在分析装备环境适应性设计基本要求的基础上,提出了按产品层次逐级进行环境适应性分析,根据其对上一级产品或整个装备系统功能的影响,层层剥离出环境适应性关键产品,通过识别环境适应性薄弱环节,消除环境适应性风险或隐患,建立了环境适应性设计关注点、环境要求、影响因素、薄弱环节、控制措施、具体方法等之间的映射关系,形成了环境适应性设计解决对策,建立了基于关键产品把控的舰船装备环境适应性设计对策分析方法,给出了方法应用示例.该方法为舰船以及其他装备开展环境适应性设计提供了一种可行的借鉴方法.  相似文献   
950.
Series of Fe/Cu-SSZ-13 catalysts with different Fe loading content were synthesized by simple one-pot strategy. The obtained catalysts were subjected to selective catalytic reduction (SCR) of NOx with NH3 and were characterized by various techniques. The results show that Fe0.63/Cu1.50-SSZ-13 catalyst with proper Fe content exhibits excellent catalytic activity with widest operation temperature window from 160 to 580°C, excellent hydrothermal stability as well as good resistance to sulfur poisoning when compared with Cu-SSZ-13, signifying its great potential for practical applications. Further characterizations reveal that the synthesized Fe/Cu-SSZ-13 catalysts present typical chabazite (CHA) structure with good crystallinity, while isolated Cu2+ and monomeric Fe3+ are revealed as the predominant copper and iron species. At low temperatures, isolated Cu2+ species act as primary active sites for SCR reaction, while monomeric Fe3+ species provide sufficient active sites for sustain the SCR activity at high temperature. Moreover, Fe over doping would lead to the damage of zeolite structure, destruction of isolated Cu2+ site, as well as the formation of highly oxidizing Fe2O3, thus causing deterioration of catalytic performances.  相似文献   
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