偏最小二乘法用于多组分的分光光度分析——钙锶钡的同时测定

文章选用对Ca、Sr、Ba较灵敏的偶氮磺Ⅲ为显色剂,考察了其在不同体系下同Ca、Sr和Ba的络合行为,确定了光度法同时测定的最佳条件。采用偏最小二乘法(PLS)为数学模型,对络合物吸收光谱完全重叠的Ca、Sr、Ba进行了同时测定。方法用于合成样品和实际地质样品的分析,结果满意。     

On comparative probabilities for normal confidence intervals by pearson's Types III and VII, and the Edgeworth series models for biotite data

Biotite crystals were counted in standard thin sections which originated from the diamond drill core of the mafic norite formation at Strathcona mine, Sudbury Nickel Irruptive. Pearson's method of moments is suitable to fit Types III and VII to the biotite data and its log ₁₀ transformation values, as the number of samples (thin sections)is large (351).Based on the two models and the Edgeworth series (utilizing the log ₁₀ data)probability values p,that biotite occurrences lie in the interval mean ± Z standard deviations is derived. Results are compared with the usual normal probability values p_Z corresponding to Zand it is shown that the Edgeworth series generated the largest pvalues for intervals when p_Z values are large; for intermediate or lower p_Z s. Types VII and III models produced larger ps, relative to the Normal and the Edgeworth series.     

海浪破碎对北太平洋海表面温度模拟的影响

基于海浪模式WAVEWATCH Ⅲ模拟北太平洋海浪要素,结合NDBC浮标资料进行验证,发现模拟出的有效波高与浮标测量值具有很好的一致性。基于改进型白冠覆盖率耗散模型,利用海浪模式模拟出的有效波高、有效波周期和摩擦速度等海浪要素计算出单位面积水柱内因海浪破碎产生的湍动能通量。通过改变环流模式sbPOM湍动能方程的上边界条件,引入海浪破碎产生的湍动能通量,并探究海浪破碎对北太平洋海表面温度模拟的影响。研究表明,由于海浪破碎的引入,环流模式sbPOM对北太平洋海表面温度模拟的准确程度得到提升,这为大气模式提供一个准确的北太平洋下边界条件具有重要意义。     

减缓气候变化的最新科学认知

 摘 要：2007年5月4日，IPCC第三工作组在泰国曼谷发布了第四次评估报告《气候变化2007：减缓气候变化》的决策者摘要及主报告。报告综合评估了2001年以来有关减缓气候变化的最新研究成果，考察分析了中短期（2030年前）和长期（2030年后）温室气体的排放情景、减排潜力、成本范围，以及稳定大气温室气体（GHG）浓度水平的可能选择。报告总体认为，未来温室气体排放取决于发展路径的选择，现有各种技术手段和许多在2030年以前具有市场可行性的低碳和减排技术，将以较低的成本实现有效减排；在2030年以后将温室气体浓度稳定在较低水平的成本并不高，但需要国际合作，采取一致行动，并认为可持续发展与温室气体减排可以相互促进。     

Role of Iron(III) and Aluminum Hydroxides in Concentration/reduction of Au(III) Complexes

Abstract: The adsorption of gold on iron(III) and aluminum hydroxides from solutions containing Au(III) complexes has been studied as a function of pH and chloride concentration at 30C. Iron(III) hydroxide was more effective in adsorbing gold from solution than aluminum hydroxide. However, both hydroxides controlled the behavior of Au(III) complex with very similar manner. The most effective gold adsorption occurred in aqueous solution with near neutral pH and low Cl concentration. In this solution condition, Au(III) complexes were mainly dissolved as AuCl₂(OH)₂^- and AuCl(OH)₃^-, and the surface charge for both hydroxides was positive. In addition, the adsorbed Au(III) complexes were spontaneously reduced to elemental gold in spite of the absence of a specific reducing agent.
The results of this study suggest that adsorption and spontaneous reduction of gold complexes on the surface of hydrous metal oxides with positive charge play an important role in gold precipitation in subsurface environment.