Liu J, Liu C, Cole M, Belkin NJ, Zhang X. Exploring and predicting search task difficulty, in Proceedings of the 21st ACM international conference on Information and knowledge management.; 2012:1313–1322.
We performed measurements of nitrous acid (HONO) during the PRIDE-PRD2006 campaign in the Pearl River Delta region 60 km north of Guangzhou, China, for 4 weeks in June 2006. HONO was measured by a LOPAP in-situ instrument which was setup in one of the campaign supersites along with a variety of instruments measuring hydroxyl radicals, trace gases, aerosols, and meteorological parameters. Maximum diurnal HONO mixing ratios of 1-5 ppb were observed during the nights. We found that the nighttime build-up of HONO can be attributed to the heterogeneous NO2 to HONO conversion on ground surfaces and the OH + NO reaction. In addition to elevated nighttime mixing ratios, measured noontime values of approximate to 200 ppt indicate the existence of a daytime source higher than the OH + NO -> HONO reaction. Using the simultaneously recorded OH, NO, and HONO photolysis frequency, a daytime additional source strength of HONO (P-M) was calculated to be 0.77 ppb h(-1) on average. This value compares well to previous measurements in other environments. Our analysis of P-M provides evidence that the photolysis of HNO3 adsorbed on ground surfaces contributes to the HONO formation.
We performed measurements of nitrous acid (HONO) during the PRIDE-PRD2006 campaign in the Pearl River Delta region 60 km north of Guangzhou, China, for 4 weeks in June 2006. HONO was measured by a LOPAP in-situ instrument which was setup in one of the campaign supersites along with a variety of instruments measuring hydroxyl radicals, trace gases, aerosols, and meteorological parameters. Maximum diurnal HONO mixing ratios of 1–5 ppb were observed during the nights. We found that the nighttime build-up of HONO can be attributed to the heterogeneous NO2 to HONO conversion on ground surfaces and the OH + NO reaction. In addition to elevated nighttime mixing ratios, measured noontime values of ≈200 ppt indicate the existence of a daytime source higher than the OH + NO→HONO reaction. Using the simultaneously recorded OH, NO, and HONO photolysis frequency, a daytime additional source strength of HONO (PM) was calculated to be 0.77 ppb h−1 on average. This value compares well to previous measurements in other environments. Our analysis of PM provides evidence that the photolysis of HNO3 adsorbed on ground surfaces contributes to the HONO formation.
In this paper, we examine the impact of family size on maternal health outcomes by exploiting the tremendous change in family size under the One-Child policy in China. Using data from the China Health and Nutrition Survey 1993-2006, we find that mothers with fewer children have a higher calorie intake and a lower probability of being underweight and having low blood pressure; meanwhile, they have a higher probability of being overweight. This would occur if a smaller family size increases the food consumption of mothers, leading underweight women to attain a normal weight and normal weight women becoming overweight. Robust tests are performed to provide evidence on the hypothesis that the tradeoff between children's quantity and mother's "quality" is through a budget constraint mechanism, that is, having more children decreases the resource allocated to mothers and affects their health outcomes.
Configuration-constrained potential energy surface calculations have been performed to investigate four-quasiparticle high- K configurations in neutron-deficient lead and polonium isotopes. A good agreement between the calculations and the experimental data has been found for the excitation energy of the observed K π = 19 − state in 188 Pb. Several lowly excited high- K states are predicted, and the large oblate deformation and low energy indicate high- K isomerism in these nuclei.