Development of a mild mercaptoethanol extraction method for determination of mercury species in biological samples by HPLC–ICP-MS

A mild, efficient and convenient extraction method of using 2-mercaptoethanol contained extractant solution combined with an incubator shaker for determination of mercury species in biological samples by HPLC–ICP-MS has been developed. The effects of the concentration of 2-mercaptoethanol, the composition of the extractant solution and the shaking time on the efficiency of mercury extraction were evaluated. The optimization experiments indicated that the quantitative extraction of mercury species from biological samples could be achieved by using 0.1% (v/v) HCl, 0.1% (v/v) 2-mercapoethanol and 0.15% (m/v) KCl extractant solution in an incubator shaker for shaking overnight (about 12 h) at room temperature. The established method was validated by analysis of various biological certified reference materials, including NRCC DOLT-3 (dogfish liver), IAEA 436 (tuna fish), IAEA MA-B-3/TM (garfish filet), IAEA MA-M-2/TM (mussel tissue), GBW 08193 (bovine liver) and GBW 08572 (prawn). The analytical results of the reference materials were in good agreement with the certified or reference values of both methyl and total mercury, indicating that no distinguishable transformation between mercury species had occurred during the extraction and determination procedures. The limit of detection (LOD) for methyl (CH₃Hg⁺) and inorganic mercury (Hg²⁺) by the method are both as 0.2 μg L⁻¹. The relative standard deviation (R.S.D.s) for CH₃Hg⁺ and Hg²⁺ are 3.0% and 5.8%, respectively. The advantages of the developed extraction method are that (1) it is easy to operate in HPLC–ICP-MS for mercury species determination since the extracted solution can be directly injected into the HPLC column without pH adjustment and (2) the memory effect of mercury in the ICP-MS measurement system can be reduced.     

Velocity map imaging of the photolysis of n-C4H9Br in UV region

Using velocity map ion imaging technique, the photodissociation of n-C₄H₉Br in the wavelength range 231–267 nm was studied. The results and our ab initio calculations indicated that the absorption of n-C₄H₉Br in the investigated region originated from the excitations to the lowest three repulsive states, as assigned as 1A″, 2A′ and 3A′ in C_s symmetry. Dissociations occurred on the PES surfaces of the three states, terminating in C₄H₉+Br (²P_3/2) or C₄H₉ + Br^* (²P_1/2) as two channels, and being impacted by an avoided crossing between the PES surfaces of the 2A′ and 3A′ states. The transition dipole to the 1A″ state was perpendicular to the symmetry plane, so perpendicular to the C–Br bond. The transitions to the 3A′ state was polarized parallel to the symmetry plane, and also parallel to the C–Br bond. While the transition dipole to the 2A′ state was in the symmetry plane, but formed an angle of about 53.1° with the C–Br bond. We have also determined the avoided crossing probabilities, which affected the relative fractions of the individual pathways, for the photolysis of n-C₄H₉Br near 234 nm and 267 nm.     

The Unusual Spectrum of the Mixture of Tin-octabutoxy Naphthalocyanine and SnCl2 in CH2Cl2

The Q-band position of tin-centered 5, 9, 14, 18, 23, 27, 32, 36-octabutoxy 2, 3-phthalocyanine(SnNc(OBu)8) exhibits dramatic red-shift as mixed with SnCl2 in CH2Cl2.     

反相高效液相色谱法分析无机阴离子研究

本文研究了提高ＲＰ－ＨＰＬＣ测定无机阴离子的选择性的方法，设计了利用对离子试剂和背景试剂兼作ｐＨ调节剂，建立了几种分离分析系统和实际样品分析方法。     

N,N-二(2-苯并咪唑亚甲基)甲胺高氯酸盐的晶体和电子结构

合成了三齿配体N,N-二(2-苯并咪唑亚甲基)甲胺(MN3)的高氯酸盐.对该化合物进行了元素分析、紫外和红外表征;采用X射线衍射方法测定了该化合物的晶体结构,依据晶体结构数据使用G98程序对配体(MN3)进行了量子化学计算.     

Ge—132与稀土离子的配合物及其对单核苷酸磷酯键的催化水解作用

Ｇｅ－１３２的羧酸阴离子与稀土离子螯合配位，生成３：１型配合物，在配合物中，Ｇｅ－１３２的ＧｅＯ３／２基团水解为Ｇｅ（ＯＨ）３，并且不参与稀土配位，系列稀土离子配合物的结构性质基本相同，在５０℃，ｐＨ值为６的水溶液中，该配合物选择性地催化５’－ＡＭＰ或５‘－ｄＡＭＰ的磷酯键水解断裂、生成相应的核苷和磷酸，而不影响碱基与戌糖之间的苷键。     

基于国际化产科教融合实训平台的教学模式改革与实践

在分析当前省属工科院校教育以能力为导向培养目标完成实施过程中遇到国际化困难问题的基础上，以青岛大学材料学科为例，提出了基于国际化产科教融合实训平台的教学模式改革举措，并经过实践验证证实其切实可行。包括：充分整合校内外材料学科整体资源，建立了国际化的产科教深度融合实训平台，构建了高效的国际化产科教深度融合协同育人实训平台动态管理运行机制；以实训平台为依托实现师资队伍、教学内容、教学模式、科研等全方位的国际化改革；基于国际化产教研融合实训平台的教学模式改革的实践收到显著成效，对全国省属高等院校理工学科专业建设国际化改革的推广有较好的示范作用。     

锂离子二次电池电解质材料LiPF6的制备及表征

0引言 液态锂离子电池自1990年开发成功以来,由于具有比能量高、工作电压高、应用温度范围宽、自放电率低、循环寿命长、无污染、安全性能好等许多独特的优势[1],所以其发展前景十分广阔.目前液态锂离子二次电池中开发使用的无机阴离子导电盐主要有LiClO4、LiPF6、LiAsF6等,但LiClO4为强氧化剂,使用不安全而不宜用于电池,LiAsF6虽然性能颇佳,但有毒且价格较贵,故也不宜广泛使用.LiPF6被认为是目前较合适的电解质[1],但其制备困难,价格较贵,且目前报道的合成方法也多是以HF为介质[2～5].本文作者以PF5和LiF为原料在CH3CN溶剂中简单有效地合成了高纯LiPF6,并通过在手套箱中制样的方法对目标产物进行了红外、热重和X射线衍射分析,给出了LiPF6的红外光谱图、热重分析数据和X射线衍射图.     

过硼酸钠对于有机物的氧化作用的研究 II: 氧化偶氮硝基苯类的合成

作者曾报道过硼酸钠在醋酸溶液中可使芳氨基氧化成硝基;McKillop等曾报道将过硼酸钠用于官能团的氧化;Huestis曾报道在冰醋酸溶液中用过硼酸钠将芳胺氧化成偶氮苯。这些都表明过硼酸钠是一种优良的氧化剂,反应条件温和、选择性强、氧化剂本身。价廉且其还原后所生成的硼酸钠易于处理和排放。因此,值得深入研究其应用范围。我们在此则报道一组以过硼酸钠为氧化剂,使芳胺氧化成氧化偶氮苯的条件。最近我们发现,在乙醇-磷酸体系中,过硼酸钠能顺     

超临界流体干燥过程的分析

以ZrOCl2•8H2O为原料，采用超临界流体干燥（SCFD）法，在短时间内制备出大孔体积高比表面ZrO2气凝胶超细粉．该法具有良好的稳定性和可靠性．建立了醇凝胶中液相含水量的分析方法，为产品质量控制及确认体系是否处于超临界状态提供了依据．对抽提后的溶剂分析表明，SCFD过程是一物理过程．对水的抽提干燥过程亦进行了初步的理论探讨．