溴素的有机化学──Ⅴ.溴代脂肪酸—2,3,5,6—四溴—1,4—苯二酯的合成

以1，4—苯二酚和不同的短链脂肪酸为基本原料，经溴代、加成、形成酰卤和酰化等反应，合成了六种新的溴化脂肪酸—2，3，5，6—四溴—1，4—苯二酯。通过对产物的碳、氢、溴等元素的定量分析，以及红外吸收光谱和氢核磁共振谱的研究，验证了化合物的结构。     

山东玲珑金矿床矿物流体包裹体中的羧酸

用离子色谱法分析了山东玲珑金矿床石英等矿物包裹体的浸取液,结果表明其中存在相当高的短链羧酸盐和少量的草酸。黄铁矿和黄铜矿浸取液中羧酸的浓度比石英浸取液的高,早期成矿阶段的矿物包裹体中一元羧酸的浓度大于主成矿阶段和晚期阶段。     

Tropospheric pyruvate changes in the remote area of northwestern China

Pyruvate is a light carboxylate in the troposphere and can act as potential cloud condensation nuclei. Due to its low concentrations, however, little work has been done on the species in precipitation. Past 43-year record of pyruvate was recovered from an ice core of Glacier 1 at 43°06′N and 86°49′E in the remote East Tianshan, northwestern China. It was revealed that pyruvate varied over a relatively large range with some below the detection limit, while part of it is so high as to be up to 70 ng·g-1. With an average concentration of 4.1 ± 8.1 ng·g-1 (mean ± 1σ, N=543), pyruvate is a minor species in comparison with other carboxylates. It is also low as compared with its precipitation in other parts of the world, suggesting a difference in its major source flux. The record revealed high pyruvate concentrations in the late halves of the 1950s and 1980s, but low in the late 1950s, late 1970s, and middle 1990s. The variation trend in the past 43 years is closely correlated with that of acetate, a major carboxylate from anthropogenic pollution to the atmosphere, indicating that tropospheric pyruvate in the remote area of northwestern China is probably a by-product in acetate formation.