Heterogeneous reactions on the surface of fine particles in the atmosphere

Fine particles play an important role in the atmosphere. Research on heterogeneous reactions on the surface of fine particles is one of the frontier areas of atmospheric science. In this paper, physical and chemical characteristics of fine particles in the atmosphere and the interactions between trace gases and fine particles are described, methods used in heterogeneous reactions research are discussed in detail, progress in the study of heterogeneous reactions on the surface of fine particles in the atmosphere is summarized, existing important questions are pointed out and future research directions are suggested.     

三江平原小叶章湿地土壤有机硫矿化特征

利用密闭培养系统，在20℃条件下研究了小叶章典型草甸和沼泽化草甸土壤有机硫的矿化，结果表明：连续培养14周后，小叶章典型草甸和小叶章沼泽化草甸土壤有机硫的矿化量分别为9．61mg／kg和6.73mg／kg，其中48.70％和51．41％来自前两周的矿化；各形态有机硫均有不同程度的矿化，其中以酯键硫的矿化量最大，碳键硫次之，未知态硫最小。土壤有机硫矿化量与培养时间之间符合曲线关系，用一级动力学方程计算土壤有机硫矿化势表明，小叶章典型草甸和小叶章沼泽化草甸土壤有机硫潜在矿化势分别为9.68mg／kg和7．25mg／kg。小叶章典型草甸土壤有机硫的矿化速率和潜力均高于小叶章沼泽化草甸。图1，表4，参12。     

深度解离高硫煤的表面特性及表征

选择具有代表性的高硫煤(山东兖州煤与重庆南桐煤)为研究对象,通过深度解离(-200目以下),采用红外光谱、X-射线衍射、电子能谱仪、扫描电镜等表征手段对两种煤中煤和黄铁矿硫的物理性质、矿物成分及解离面的表面化学组成、界面物理化学特性差异进行分析。研究揭示高硫煤在高解离度下煤与煤系黄铁矿硫的物理特性、表面特性、煤与煤系黄铁矿硫表面特性的差异.     

Authigenic sulfide minerals and their sulfur isotopes in sediments of the northern continental slope of the South China Sea and their implications for methane flux and gas hydrate formation

This is a report of the study of the authigenic sulfide minerals and their sulfur isotopes in a sediment core (NH-1) collected on the northern continental slope of the South China Sea, where other geo-physical and geochemical evidence seems to suggest gas hydrate formation in the sediments. The study has led to the findings: (1) the pyrite content in sediments was relatively high and its grain size relatively large compared with that in normal pelagic or hemipelagic sediments; (2) the shallowest depth of the acid volatile sulfide (AVS) content maximum was at 437.5 cm (>2 μmol/g), which was deeper than that of the authigenic pyrite content maximum (at 141.5-380.5 cm); (3) δ 34S of authigenic pyrite was positive (maximum: 15‰) at depth interval of 250-380 cm; (4) the positive δ 34S coincided with pyrite enrichment. Compared with the results obtained from the Black Sea sediments by Jorgen-sen and coworkers, these observations indicated that at the NH-1 site, the depth of the sulfate-methane interface (SMI) would be or once was at about 437.5-547.5 cm and the relatively shallow SMI depth suggested high upward methane fluxes. This was in good agreement with the results obtained from pore water sulfate gradients and core head-space methane concentrations in sediment cores collected in the area. All available evidence suggested that methane gas hydrate formation may exist or may have existed in the underlying sediments.     

黔西北地区铅锌矿硫同位素特征研究

通过对黔西北地区铅锌矿中硫化物硫同位素的分析表明,各铅锌矿床具有硫同位素组成较为均一,但水城与赫章地区硫同位素组成差异显著的特点。综合分析认为,区内铅锌矿床中的硫可能主要来源于含矿围岩之外的多个膏盐层。     

用VB辅助分析质谱碎片结构

利用本程序可以非常方便地解决有机化合物的质谱测定中离子碎片的结构测定问题．     

煤化工企业含苯有机尾气的回收

化工生产过程中产生含有有机物的尾气,排放到空气中不仅造成环境污染,还是资源的一种浪费。本文根据粗苯加氢物料、工艺、装置及公辅供应等特点,选用冷凝法对真空尾气进行回收利用,不仅减少了污染物的排放,还取得了一定的经济效益。     

对几道有机化学反应式写法的辨析

依据化学反应历程对几种不同教科书中的烯烃与卤素加成、氢化铝锂或硼氢化钠还原醛酮、卤仿反应的相关习题进行科学的辨析，对如何得出准确、规范和严谨的答案进行探讨。     

有机溶剂法纯化麦草碱木质素

采用有机溶剂法纯化麦草碱本质麦，研究了不同有机溶剂体系对麦草碱木质素纯化得率及纯化产品化学组成的影响。确定了适宜的有机溶剂体系及纯化工艺条件，结果表明：丙酮和水的混合溶剂为最佳的溶剂体系，丙酮和水的体积配比为１：１时，纯化所得碱木质素的得率为９２．２４％，产品中木质素的含量由原来的２６．１２％提高到４１．５４％，糖含量由１６．１４％降至３．４３％，灰分含量由３４．２９％降至２７．１２％。     

5—氨基四唑的合成

由氨基胍碳酸盐制备5—氨基四唑,在盐酸中使氨基胍碳酸盐重氮化.重氮盐用醋酸钠中和。加热。