区域酸性沉降的数值研究 I. 模式

建立了一个三维时变的欧拉型区域酸性污染物沉降模式，模式包括源排放、平流输送、湍流扩散、干沉积、气相化学、液相化学及湿清除等六大部分。考虑到计算条件的承受能力和应用性的要求，在把握酸沉降形成的关键过程的前提下，合理地简化设计模式。相对于国内已有的工作，本模式在干沉积、气相化学、液相化学和湿清除等方面均有所改进。     

三元体系RECl_3（RE＝Dy，Yb）－HOAc－H_2O（30℃）的研究

测定了三元体系ＲＥＣｌ３（ＲＥ＝Ｄｙ，Ｙｂ）－ＨＯＡｃ－Ｈ２Ｏ（３０℃）的平衡态的溶度数据并绘制了相应的溶度图。在两个体系中分别得到了ＤｙＣｌ３·６Ｈ２Ｏ和ＹｂＣｌ３·６Ｈ２Ｏ两种固相。依据ＨＯＡｃ对ＤｙＣｌ３·６Ｈ２Ｏ和ＹｂＣｌ３·６Ｈ２Ｏ有盐抗作用这一结论得到了一种制备ＤｙＣｌ３·６Ｈ２Ｏ和ＹｂＣｌ３·６Ｈ２Ｏ的ＨＣｌ—ＨＯＡｃ法。同时，在分析测定酸的重量百分浓度时，利用“差减法”得到了Ｈ＋的准确含量。     

等离子体发射光谱法分析毒砂单矿物

研究了大孔膦酸树脂对毒砂中主、次和痕量元素的吸附行为及洗脱条件,结合巯基棉和TBP柱分离技术,建立了两个分离流程。在J-A1160型多道直读光谱仪上实现了毒砂单矿物中包括主量元素Fe和As在内的20个元素测定。主量元素As和Fe的相对标准偏差(n为5～10)分别为1.03％和0.9％,其它元素在5％～11％范围。流程经实际试样分析验证,结果与化学法相符。     

过量酸性铬蓝K隐色光度法测定铜的研究

在pH 4.0的微酸性介质中,酸性铬蓝K同Cu~(2+)形成稳定的红色络合物,用H_2O_2为隐色剂可以隐去过量显色剂的颜色,消除高色度背景的影响。络合物的最大吸收波长为540nm,摩尔吸光系数为1.6×10~4L·mol~(-1)·cm~(-1),Cu量在0～1.4μg/ml范围服从比尔定律。方法已应用于测定矿样中的Cu。     

盐湖相低熟油脂肪酸的组成与分布特征

对泌阳凹陷碱性盐湖相、舞阳凹陷盐湖相、襄城凹陷膏盐湖相、南阳凹陷淡水湖相低熟油脂肪酸组成和分布特征进行了分析与研究。结果表明这些不同盐湖相的低熟原油的脂肪酸为丰度不同的饱和正构酸、不饱和正构酸、少量异构酸、类异戊二烯酸及脂肪酸乙酯系列化合物。脂肪酸的组成和分布反映了原始有机质的来源。     

Products and Mechanism of the Gas Phase Reaction of Ozone with β-Pinene

Gas phase ozonolysis of -pinene was performedin a 570 l static reactor at 730 Torr and 296 K insynthetic air and the products were analysed by acombination of gas phase FTIR spectroscopy, HPLC andIC analyses of gas phase and aerosol samples,respectively. The reaction mechanism was investigatedby adding HCHO, HCOOH and H₂O as Criegeeintermediate scavenger and cyclohexane as OH radicalscavenger. Main identified products (yields inparentheses) in the presence of cyclohexane as OHradical scavenger were HCHO (0.65 ± 0.04),nopinone (0.16 ± 0.04), 3-hydroxy-nopinone (0.15± 0.05), CO₂ (0.20 ± 0.04), CO (0.030± 0.002), HCOOH (0.020 ± 0.002), the secondaryozonide of -pinene (0.16 ± 0.05), andcis-pinic acid (0.02 ± 0.01). The decompositionof the primary ozonide was found to yieldpredominantly the excited C₉-Criegee intermediateand HCHO (0.84 ± 0.04) and to a minor extent theexcited CH₂OO intermediate and nopinone (0.16± 0.04). Roughly 40% of the excitedC₉-Criegee intermediate becomes stabilised andcould be shown to react with HCHO, HCOOH and H₂O. The atmospherically important reaction of thestabilised C₉-Criegee intermediate with H₂Owas found to result in a nopinone increase of (0.35± 0.05) and in the formation of H₂O₂(0.24 ± 0.03). Based on the observed products,the unimolecular decomposition/isomerisationchannels of the C₉-Criegee intermediate arediscussed in terms of the hydroperoxide and esterchannels. Subsequent reactions of the nopinonylradical, formed in the hydroperoxide channel, lead tomajor products like 3-hydroxy-nopinone but also tominor products like cis-pinic acid. A mechanismfor the formation of this dicarboxylic acid isproposed and its possible role in aerosol formationprocesses discussed.     

抑制型离子色谱法同时测定水中锂和锶

对离子色谱法测定水中的锂、锶含量及其影响因素进行了研究。以甲烷磺酸为流动相，用IonPacCS12A阳离子色谱柱分离后，电导检测器同时测定矿泉水中锂和锶，其检出限分别为0．003mg／L和0．006mg／L。对Li^＋和Sr^2＋的离子色谱条件进行了优化，并对流动相的选择及干扰离子的影响进行了讨论。     

微波消解-等离子体发射光谱法同时测定水中硅铁钠

讨论使用电感耦合等离子体发射光谱法测定水样中si、Fe、Na时，四种水样前处理方法对测试结果的影响。提出采用HNO3^-HF体系微波消解、H3BO3掩蔽HF的方法前处理水样，用等离子体发射光谱法可同时准确快速地测定水中Si、Fe、Na三种元素的含量。5次测定的相对标准偏差小于4％，加标回收率为89．2％-106％。     

Mathematical expressions used in amino acid racemisation geochronology—A review

A variety of mathematical expressions that describe changes over time (t) in the extent of amino acid racemisation (AAR, expressed as the ratio of d- to l-amino acid isomers or epimers) have been used in Quaternary geochronology. The integrated rate equation was first used to estimate fossil age from D/L but its geochronological utility is disadvantaged by uncertainties regarding the conformity of AAR in fossil protein to apparent reversible first-order kinetics for the entire reaction history. ‘Non-linear’ models have subsequently been used to relate D/L to t. The logarithmic equation successfully applied to Atlantic Coastal Plain research has not achieved widespread application, perhaps due to the regional calibration required if sensitivity to temperature is to be modelled, or the difficulties encountered when extending the model to include fossils with D/L<0.1. Success producing a linear correlation between D/L transformed with a power function and t has seen this approach emerge as one of the most commonly applied in AAR geochronology in recent years. Like parabola curve fitting, which has been applied to trends in D/L versus t in a variety of fossils and geographic settings, power transformations may not be suitable for geochronological modelling during the latter stages of amino acid diagenesis. Several studies have demonstrated the utility of simple and contingent linear equations for relating D/L to t. Future research should aim to reduce reliance on independent calibration and explore the geochronological benefits of AAR in pools other than the total hydrolysable amino acids.