Neutron Activation Analysis Applied to the Determination of Heavy Metals and Other Trace Elements in Sediments from Sepetiba Bay (RJ), Brazil

In this work, instrumental neutron activation analysis (INAA) was applied to the determination of the elements As, Ba, Br, Ce, Co, Cr, Cs, Eu, Fe, Hf, La, Lu, Nd, Rb, Sc, Sm, Ta, Tb, Th, U, Yb, Zn in twenty eight bottom sediment samples from Sepetiba Bay, Rio de Janeiro, Brazil. With the concentration data obtained, contour maps were prepared, by using Kriging method, to show the spatial distribution of the studied elements in the Bay. The elements Co, Cr, Cs, Fe, Sc, Ta and Zn showed similar behaviour in the sediments, with higher concentrations along the northern coast of the bay, where the fluvial water inputs are concentrated. The distribution of U, rare earth elements and Ba in the Bay indicates that these elements are not deposited as contaminants.     

Geochemistry, mineralogy, and technological properties of the main Stephanian (Carboniferous) coal seams from the Puertollano Basin, Spain

This study is focused on the occurrence and distribution of mineral matter and major and trace elements in the high volatile bituminous coal from Puertollano (south-central Spain). The relationship between ash behaviour and inorganic composition, as well as the possible formation of fouling and slagging deposits in boilers during the conversion process, were investigated. The Puertollano coals do not exhibit plastic properties, despite their rank, probably because of their high ash and inertinite contents.The Puertollano coal has medium to low total S content (0.48% to 1.63% db, with a mean of 1.0% db) and is characterised by relatively high contents of Si, Pb, Sb, and Cs. Some elements such as As, Cd, Co, Cr, Cu, Ge, Li, Mn, Ni, W, and Zn are also present in relatively high contents. The enrichment in a number of heavy metals could be attributed to the common sulphide ores occurring near the Puertollano coal deposit.The following trace elements affinities are deduced: (a) sulphide affinity: As, Co, Cd, Cu, Ni, Sb, Tl, and Zn; (b) aluminum–silicate affinity: K, Ti, B, Co, Cr, Cs, Cu Ga, Hf, Li, Nb, Rb, Sn, Ta, Th, V, Zr, and LREE; (c) Carbonate affinity: Ca, Mg, Mn, and B; (d) organic affinity: B.The very high Si levels and the anomalous enrichment in Cs, Ge, Pb, Sb, and Zn shown by the Puertollano coals account for the high contents of these elements in the Puertollano fly ash when compared with the other Spanish coal fly ashes.The chemical composition of the high temperature ash (HTA) is consistent with the trend shown by the ash fusion temperatures (AFT) and also with the predictive indices related to slagging and fouling propensities. Thus, the ash fusion temperatures increase with high values of Al₂O₃ as well as with the decrease in Fe₂O₃, CaO, and MgO.     

山东省飞机增雨降水区分级预报方法研究

利用1997～2000年春秋季山东主要降水天气系统中尺度客观分析和降水模拟资料，统计分析了与降水密切相关的15个因子，并对因子的稳定性进行检验。用全部入选因子的前5个主成分作为新的预报因子，建立全省25个区域0～6h和0～12h平均降水量的3类判别方程，判别效果较好。以此方法为基础建立的决策系统为增雨作业指挥提供了实用性技术工具。     

多普勒速度图暴雨判据和短时预报工具研究

对3824-C波段全相参多普勒天气雷达1995-1999年径向速度场资料中逆风区进行统计分析，认为近距离逆风区可成为暴雨短时预报的一个有参考价值的判据，并给出人机交互识别逆风区工具的设计和实现方法。     

多钨酸钠超声高速离心法——分离提纯微细矿物的新方法

多乌酸钠是一种无毒、无气味、易溶解、易配制、稳定性好、回收率高、使用方便安全的新型无机重液，其密度变化范围为1．0g/cm^3-3.1g/cm^3，分离缙云沸石和粘土矿土矿物取得了良好的效果。详述了多钨酸钠溶液的配制和回收，分离缙云沸石和粘土的实验流程及其应用前景。     

中尺度暴雨云团发生发展前的一些征兆

利用湿有效能量方法找出了盛夏午后北京地区中尺度暴雨云团发生发展的一些征兆：（１）北京地区已贮存着大量能量；（２）湿有效能量正在北京地区积聚；（３）低层流场结构有利于出现强迫抬升；（４）北京地区与河套地区之间午后将出现非绝热加热形成的巨大水平温差。     

Efficiency of Severe Recorded Rainstorms over Maharashtra State

12 severe rainstorms have been experienced by different meteorological sub-divisions of Maharashtra State during the last 100-year period from 1891-1990. For each of the rainstorms efficiency factors (i.e. P/ M ratios) were worked out for maximum one-day duration and for three standard areas of 1000, 5000, and 10,000 km2. Comparison of these ratios with the past has shown that the most efficient rainstorm over Maharashtra was the rainstorm of June, 1908 over the Vidarbha region whose full DAD data as well as isohyetal pattern have been given.     

兰州盛夏大降水短期预报

根据预报员的思路，运用专家系统匹配方法，依次对大降水的环流场、影响系统、高低空物理量配置等建立推理规则，然后输入计算机算出结果。