Quantum yields for photochemical production of NO2 from organic nitrates at tropospherically relevant wavelengths.
Quantum yields for photochemical production of NO2 from organic nitrates at tropospherically relevant wavelengths.
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在对流层相关波长下从有机硝酸盐光化学生产 NO2 的量子产率。
DOI：
10.1021/jp501517t
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发表时间：
2014
期刊：
影响因子：
--
通讯作者：
Higgins CM
中科院分区：
文献类型：
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作者：
Higgins CM
报道了294 K下气态甲基、乙基、正丙基和硝酸异丙基的吸收截面和产量子产率（ΦNO2）。在240 ~ 320 nm波长范围内的吸收截面与先前的测定结果吻合较好。在290、295和315 nm的光激发波长下，no2的量子产率在实验不确定度范围内是一致的，并且在250-700 Torr的总样品压力范围内与浴气（N2）压力无关。当在所有波长和样品压力下取平均值时，ΦNO2are的值为1.03±0.05（硝酸甲酯）、0.98±0.09（硝酸乙酯）、1.01±0.04（硝酸正丙基）和1.00±0.05（硝酸异丙基），不确定度对应于1个标准差。将硝酸乙酯、硝酸异丙基和两种不饱和硝酸盐化合物丁-3-烯-1,2-二硝酸酯和(Z)-丁-2-烯-1,4-二硝酸酯在乙腈溶液中的吸收截面与气相值进行了比较，在260 ~ 315 nm波长范围内，将液相截面分别除以2.0、1.6、1.7和2.2，可以很好地再现气相值。因此，对低挥发性有机硝酸盐的气相吸收截面的合理估计可以通过将乙腈溶液的值减半来获得。在290 nm光激发下，丁-3-烯-1,2-二硝酸酯生成no2的量子产率明显低于烷基（单）硝酸盐的量子产率：从实验测量中获得的最佳估计为ΦNO2≤0.25。
Absorption cross-sections and quantum yields for NO2production (ΦNO2) are reported for gaseous methyl, ethyl,n-propyl, and isopropyl nitrate at 294 K. Absorption cross-sections in the wavelength range of 240–320 nm agree well with prior determinations. NO2quantum yields at photoexcitation wavelengths of 290, 295, and 315 nm are unity within experimental uncertainties for all of the alkyl nitrates studied and are independent of bath gas (N2) pressure for total sample pressures in the range of 250–700 Torr. When averaged over all wavelengths and sample pressures, values of ΦNO2are 1.03 ± 0.05 (methyl nitrate), 0.98 ± 0.09 (ethyl nitrate), 1.01 ± 0.04 (n-propyl nitrate), and 1.00 ± 0.05 (isopropyl nitrate), with uncertainties corresponding to 1 standard deviation. Absorption cross-sections for ethyl nitrate, isopropyl nitrate, and two unsaturated dinitrate compounds, but-3-ene-1,2-diyl dinitrate and (Z)-but-2-ene-1,4-diyl dinitrate in acetonitrile solution, are compared to gas-phase values, and over the wavelength range of 260–315 nm, the gas-phase values are well-reproduced by dividing the liquid-phase cross-sections by 2.0, 1.6, 1.7, and 2.2, respectively. Reasonable estimates of the gas-phase absorption cross-sections for low-volatility organic nitrates can therefore be obtained by halving the values for acetonitrile solutions. The quantum yield for NO2formation from photoexcitation of but-3-ene-1,2-diyl dinitrate at 290 nm is significantly lower than those for the alkyl (mono) nitrates: a best estimate of ΦNO2≤ 0.25 is obtained from the experimental measurements.
DOI：
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发表时间：
1973
期刊：
影响因子：
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作者：
V. Csizmadia;S. A. Houlden;G. Koves;J. Boggs;I. Csizmadia
通讯作者：
I. Csizmadia
C3C5 硝酸盐的紫外吸收截面和光解产物的温度依赖性
影响因子：
2.8
作者：
Lei Zhu;D. Kellis
通讯作者：
D. Kellis
DOI：
10.1039/c001425g
发表时间：
2010-06
期刊：
Physical chemistry chemical physics : PCCP
影响因子：
--
作者：
P. G. Carbajo;A. Orr-Ewing
通讯作者：
P. G. Carbajo;A. Orr-Ewing