PMBP—泡塑萃取行为研究及其应用—岩石、水系沉积物中15个痕量稀土化学光谱法定量测定

近些年来,国内外在痕量稀土的测定上取得重要进展。但均采用了先进的近代仪器,如1CP-光量计,中子活化,火花质谱,X-荧光光谱等。本法采用PMBP—泡塑萃取富集,以国产一米光栅摄谱仪测定15个痕量稀土,检出限0.6—300ppb,多次测定精密度(RSD)除铽±18.2％外,其余在±4.7—±13.9％之间。     

PMBP-泡塑萃取稀土行为研究及其应用—水中痕量稀土15个元素光谱定量测定

本文研究了PMBP—泡塑对水相中15个痕量稀土的萃取行为,发现在pH2.5—4的50ml水溶液中具有定置萃取特征,给出了令人满意的泡塑对稀土吸附率与回收率,并在此基础上建立了水中痕量15个稀土的光谱定量测定方法,同时为岩石及水系沉积物中15个痕量稀土化学光谱法奠定了实验基础。     

Production of γ-linolenic acid and stearidonic acid by <Emphasis Type="Italic">Synechococcus</Emphasis> sp. PCC7002 containing cyanobacterial fatty acid desaturase genes

Genetic modification is useful for improving the nutritional qualities of cyanobacteria. To increase the total unsaturated fatty acid content, along with the ratio of ω-3/ω-6 fatty acids, genetic engineering can be used to modify fatty acid metabolism. Synechococcus sp. PCC7002, a fast-growing cyanobacterium, does not contain a Δ6 desaturase gene and is therefore unable to synthesize γ-linolenic acid (GLA) and stearidonic acid (SDA), which are important in human health. In this work, we constructed recombinant vectors Syd6D, Syd15D and Syd6Dd15D to express the Δ15 desaturase and Δ6 desaturase genes from Synechocystis PCC6803 in Synechococcus sp. PCC7002, with the aim of expressing polyunsaturated fatty acids. Overexpression of the Δ15 desaturase gene in Synechococcus resulted in 5.4 times greater accumulation of α-linolenic acid compared with the wild-type while Δ6 desaturase gene expression produced both GLA and SDA. Co-expression of the two genes resulted in low-level accumulation of GLA but much larger amounts of SDA, accounting for as much to 11.64% of the total fatty acid content.     

痕量金价态分离与分析及在勘查地球化学研究中的作用

本文验证并借助泡塑对价态金吸附选择性成功地实现了痕量Ａｕ（Ⅲ）、Ａｕ（Ⅰ）与Ａｕ（０）的分离，土壤加标回收满意。研制的痕量金价态分离与分析方法已在化探实践中初步运用。     

泡塑吸附痕量钨钼铌钽锑铼研究

研究了泡塑在三种介质中对钨、钼、铌、钽、锑、铼的吸附行为。试验表明：介质、络离子类型与性质及其变化决定了泡塑吸附定量、动力学特性及其机理，并由此建立了可供分析实践的几种泡塑吸附体系。