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Li Xin Jia Chao Zhao Hualin Teng Yongbo Zhang Yi Zhang Pengpeng 《Environmental science and pollution research international》2023,30(5):11617-11633
Environmental Science and Pollution Research - The Bohai Sea has unique characteristics of the marine geological environment, with strong water closure and weak self-purification ability.... 相似文献
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Miaomiao Fan Linjun Li Jinsuo Lu Heliang Pang Zhiqiang Zhang Jing Yang Pengpeng Li Xiaoyu Yan 《环境科学学报(英文版)》2023,35(2):901-914
Scale not only affects the taste and color of water, but also increases the risks of osteoporosis and cardiovascular diseases associated with drinking it. As a popular beverage, tea is rich many substances that have considerable potential for scale inhibition, including protein, tea polyphenols and organic acids. In this study, the effect of tea brewing on scale formation was explored. It was found that the proteins, catechins and organic acids in tea leaves could be released when the green tea was brewed in water with sufficient hardness and alkalinity. The tea-released protein was able to provide carboxyl groups to chelate with calcium ions (Ca2+), preventing the Ca2+ from reacting with the carbonate ions (CO32−). The B rings of catechins were another important structure in the complexation of Ca2+ and magnesium ions (Mg2+). The carboxyl and hydroxyl groups on the organic acids was able to form five-membered chelating rings with Ca2+ and Mg2+, resulting in a significant decrease in Ca2+ from 100.0 to 60.0 mg/L. Additionally, the hydrogen ions (H+) provided by the organic acids consumed and decreased the alkalinity of the water from 250.0 to 131.4 mg/L, leading to a remarkable reduction in pH from 8.93 to 7.73. It further prevented the bicarbonate (HCO3−) from producing CO32− when the water was heated. The reaction of the tea constituents with the hardness and alkalinity inhibited the formation of scale, leading to a significant decrease in turbidity from 10.6 to 1.4 NTU. Overall, this study provides information to help build towards an understanding of the scale inhibition properties of tea and the prospects of tea for anti-scaling in industrial applications. 相似文献
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温度、曝气和沉积物对绿潮硬毛藻分解的影响 总被引:2,自引:0,他引:2
为了解绿潮优势种——硬毛藻在温度、曝气和沉积物作用下的分解过程及三因素的效应大小,通过室内模拟研究了不同环境条件下硬毛藻早期分解过程中生物量、分解速率及藻体磷释放率的变化,分析了不同环境因子对藻体分解影响的效应大小.结果表明,高温(20~30℃)和添加沉积物均能促进硬毛藻的腐烂分解及藻体磷素释放,其中,30℃条件下含沉积物处理的最大分解速率可达12.13%·d-1,14 d后藻体磷释放率为90%以上.曝气一方面可通过扰动加速藻体生物量的损失和分解速率,另一方面提供了好氧环境,抑制了藻体生物分解和磷素释放,因而其影响效应较低.研究表明,高温和添加沉积物均可加速丝状硬毛藻的分解和藻体磷素释放,夏季应及时清除水体中滋生和衰亡的藻体. 相似文献
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