黄腐酸络合铜离子光谱学特征及机理构建

二价金属离子C u2+在很多工矿企业周围水源及土壤中存量超标,造成生态环境恶化,传统的药剂及生物处理容易产生二次污染.黄腐酸由性质相似分子团簇构成,具有水溶性好、络合作用强及化学活性高的特点,对环境中C u2+分布、迁移和生物利用度可以实现高效控制与环保处理,是近年科学研究热点.现代多光谱表征分析有助于揭示黄腐酸与金属...     

近红外光谱技术在检测转基因油菜籽中芥酸和硫甙上的应用研究

随着转基因食品的迅速发展,人们越来越关心其食用安全性。以转基因油菜及其亲本为实验材料,借助于近红外光谱仪对转基因油菜及其亲本中的芥酸和硫甙进行了测定分析：扫描区间为12 000～4 000 cm-1,分辨率为4 cm-1,扫描次数为64次。结果显示近红外检测样品的结果与通用方法结果相近,说明通过扫描光谱加上数学和计算机软件分析,非常准确、方便的测定了转基因油菜中的芥酸和硫甙。结果表明,转基因油菜中的芥酸含量明显高于亲本中的含量,芥酸含量是非转基因亲本1.5～2.0倍;硫甙含量也表现出芥酸相同的规律,转基因油菜中显著高于其相应亲本,是亲本含量的1.3～1.51倍以上。所以,在转基因作物的育种过程中,在改善个别性状的同时,如何保持其他优良性状应当引起重视。     

Synergistic effect between 4-(2-pyridylazo) resorcin and chloride ion on the corrosion of cold rolled steel in 0.5 M sulfuric acid

The corrosion inhibition of 1-(2-pyridylazo)-2-naphthol (PAR) on the corrosion of cold rolled steel in 0.5 M sulfuric acid (H₂SO₄) was studied using weight loss method and potentiodynamic polarization method. Results obtained revealed that together with chloride ion, PAR is an effective corrosion inhibitor for steel corrosion in sulfuric acid. It was found that for steel corrosion inhibition in the presence of single PAR in sulfuric acid the Temkin adsorption isotherm may be used to explain the adsorption phenomenon. For the mixture of PAR and NaCl used as corrosion inhibitor, however, the Langmuir adsorption isotherm can be used to satisfactorily elucidate the adsorption of mixture of PAR and NaCl. Potentiodynamic polarization studies showed that single PAR mainly acts as a cathodic inhibitor for the corrosion of steel in 0.5 M sulfuric acid. The mixture of PAR and chloride ion, however, acts as a mixed type inhibitor that mainly inhibits cathodic reaction of the steel corrosion in sulfuric acid. By means of electrochemical polarization tests, a desorption potential at ca. −370 mV was observed for the adsorption of mixture of PAR and chloride ion, when potential reaches this value, adsorbed inhibitor molecule heavily departs from the steel surface. For the mixture of PAR and chloride ion, thermodynamic parameters such as adsorption heat, adsorption entropy and adsorption free energy were obtained from experimental data of the temperature studies of the inhibition process at four temperatures ranging from 30 to 45 °C, the kinetic data such as apparent activation energies and pre-exponential factors at different concentrations of the inhibitor were calculated, and the effect of the apparent activation energies and pre-exponential factors on the corrosion rates of cold rolled steel was discussed. The most suitable range of inhibitor concentration was discussed. The inhibitive action was satisfactorily explained by using both thermodynamic and kinetic models. Synergism between chloride ion and PAR was proposed. The results obtained from weight loss and potentiodynamic polarization were in good agreement.     

盐酸煮沸提取原子吸收法测定乳和乳制品中矿质元素

本研究了盐酸煮沸提取乳和乳制品中的Ｋ、Ｎａ、Ｃａ、Ｍｇ、Ｆｅ和Ｚｎ六个矿质元素的实验条件,１ｍｏｌ·Ｌ＾－１盐酸提取液用火焰原子吸收法（ＦＡＡＳ）测定,得到满意的结果。方法具有操作简便,安全,快速的特点。与高温干灰化法对十种样品进行结果对照,无论液体样品或样品,其结果都非常一致,不存在显差异,结果具有很好的准确度和精密度。