PHOTOCHEMICAL FORMATION OF H2O2 IN NATURAL-WATERS EXPOSED TO SUNLIGHT
PHOTOCHEMICAL FORMATION OF H2O2 IN NATURAL-WATERS EXPOSED TO SUNLIGHT
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DOI：
10.1021/es00175a004
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发表时间：
1988-10-01
影响因子：
11.4
通讯作者：
PLANE, JMC
中科院分区：
文献类型：
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作者：
COOPER, WJ;ZIKA, RG;PLANE, JMC
大多数天然沃茨暴露在阳光下时会形成过氧化氢。H2 O2积累的速率与这些沃茨中吸收光（> 295 nm）的有机物质的浓度有关。已经测量了几种地表沃茨和地下沃茨在阳光中的H2 O2的光化学积累速率，发现其为2.7 × 10 - 6。10-7 48次10-7 mol L ~（-1）h ~（-1），溶解有机碳（DOC）沃茨范围为0.53 ~ 18 mg L ~（-1）。这些速率是在正午阳光，0.4W m-2（295-385 nm），纬度24.3 °下测定的。N.测定了天然沃茨中H_2O_2在不同波长下的表观量子产率。这些量子产率随着波长的增加而降低，从近紫外的10-3到可见光谱范围的10-6。量子产率已被用于光化学模型计算天然水样中H2 O2的积累速率。模型计算同意H2 O2积累率从暴露三个不同的水样在阳光下。
Hydrogen peroxide is formed in most natural waters when they are exposed to sunlight. The rate at which H2O2 accumulates is related to the concentration of light-absorbing (> 295 nm) organic substances in these waters. The photochemical accumulation rate of H2O2 in sunlight has been measured for several surface waters and groundwaters and was found to be 2.7 .times. 10-7 to 48 .times. 10-7 mol L-1 h-1, in waters ranging from 0.53 to 18 mg L-1 dissolved organic carbon (DOC) respectively. These rates were determined in midday sunlight, 0.4 W m-2 (295-385 nm), latitude 24.3.degree. N. Apparent quantum yields of H2O2 have been determined for natural waters at different wavelengths. These quantum yields decreased with increasing wavelength, from 10-3 in the near-ultraviolet to 10-6 in the visible spectral range. The quantum yields have been used in a photochemical model to calculate H2O2 accumulation rates of natural water samples. Model calculations agree with H2O2 accumulation rates obtained from exposing three different water samples to sunlight.