概括
北美东部的降雨显示,由于化石燃料燃烧, (H(+) 硫酸盐 (SO(4) ((2-)) 和酸盐 (NO(3) ((-)) 度增加. 与偏远地区的比较显示了这些离子的显著丰富,特别是硫酸盐.
科学领域:
- 环境科学 环境科学
- 大气化学 大气化学
- 生态生态学 生态生态学
背景情况:
- 化石燃料的燃烧在历史上增加了沉中的酸化离子度.
- 1950年前的降水数据很少,这限制了对绝对离子度增加的理解.
- 酸性沉积对生态系统产生影响,需要对关键离子进行精确的监测.
研究的目的:
- 为了评估北美东部降水中的当前离子度.
- 为了比较敏感于酸性沉积的地区和偏远地区的降水化学.
- 量化 (H(+) 硫酸盐 (SO(4) ((2-)) 和酸盐 (NO(3) ((-)) 离子的丰富.
主要方法:
- 分析来自北美东部的降水数据.
- 敏感和偏远地理区域之间的离子度的比较.
- 作为一个生态指标,硫酸盐 (SO(4) ((2-)) 丰富的量化.
主要成果:
- 许多北美东部地区的降雨量显示,气度 (+),气度 (4-2) 和气度 (3-1) 比偏远地区要高得多.
- 与偏远地区相比,在北美东部的降水中,硫酸盐 (SO(4) ((2-)) 度比偏远地区高2至16倍.
- 这种丰富凸显了人为排放对降水化学的广泛影响.
结论:
- 北美东部目前的降雨明显比偏远地区更酸性.
- 硫酸盐 (SO(4)(2-)) 是人类对降水化学的影响的一个关键指标.
- 该研究提供了由化石燃料燃烧驱动的重大环境变化的证据.
相关概念视频
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In gravimetry, the precipitant is chosen carefully to obtain a pure solid that can be easily filtered. Common inorganic precipitants can be used to determine several cations and anions. In some cases, the formation of the same precipitate can be used to determine the cation and the anion. For example, the reaction of barium and chromate ions to give barium chromate is used to determine both barium and chromate. However, precipitates such as hydroxides, oxalates, and metal ammonium phosphates...


