X射线荧光光谱法测定重整铂催化剂中氯

建立重整铂催化剂中氯的X射线荧光光谱测定方法。通过研磨机将铂催化剂研磨至粒径小于75 μm的颗粒,采用仪器压片制样,通过测量不同氯含量样品的计数率,建立铂催化剂中氯含量与计数率的线性关系。氯的质量分数在0.85%~1.04%范围内与计数率成良好的线性关系,相关系数为0.9995,检出限为0.0076%。样品加标回收率为96.2%~104.2%,测定结果的相对标准偏差小于2%(n=6)。该法测定结果与电位滴定法相吻合。该方法精密度高,分析速度快,满足重整装置生产调整的要求。     

Determination of 90Sr in different matrices via ion-exchange chromatography and LSC

Journal of Radioanalytical and Nuclear Chemistry - A cation-exchange chromatographic method was utilized to isolate strontium. The interference of recovery yield, calcium and magnesium, and the...     

Development and validation of an LC/MS/MS method for simultaneous determination of shionone and epi‐friedelinol in rat plasma for pharmacokinetic study after oral administration of Aster tataricus extract

A rapid and sensitive liquid chromatography tandem mass spectrometry (LC/MS/MS) method was developed and validated using spinasterol as the internal standard (IS) for the simultaneous determination of shionone and epi‐friedelinol in rat plasma. Plasma samples were pretreated using liquid–liquid extraction with ethyl ether. Chromatographic separation was achieved on a C₁₈ column (100 × 2.1 mm, 5 μm) with an isocratic elution consisting of acetonitrile–0.1% formic acid water (75:25, v/v) at a flow rate of 0.30 mL/min. Detection was performed under the selected reaction monitoring scan using an electrospray ionization in the positive ion mode. The mass transitions were as follows: m/z 427.4 → 95.1 for shionone, m/z 411.4 → 205.2 for epi‐friedelinol and m/z 395.3 → 105.2 for IS. All calibration curves exhibited good linearity (r > 0.995) over the concentration range for both components. The intra‐ and inter‐day precisions at three QC and lower limit of quantitation levels were both <10.21% in terms of relative standard deviation, and the accuracy ranged from ?7.13 to 8.02% in terms of relative error. The extraction recoveries of the compounds ranged from 82.07 to 89.81%. The developed method was successfully applied to the pharmacokinetic study of shionone and epi‐friedelinol after oral administration of Aster tataricus extract to rats. Copyright © 2015 John Wiley & Sons, Ltd.     

Nucleophilic substitution of ferrocenyl alcohols catalyzed by bismuth(III) in aqueous medium at room temperature

A nucleophilic substitution reaction of an α‐ferrocenyl alcohol with various amines, indoles and thiols was successfully developed by using a catalytic amount of Bi(NO₃)₃.5H₂O at room temperature without the aid of phase transfer catalyst. The reactions proceeded in aqueous media, leading to the formation of new C=C, C=N and C=S bonds bearing ferrocenyl substituent with high efficiency. Copyright © 2012 John Wiley & Sons, Ltd.     

壳模型哈密顿量本征值的美与奇

本征值问题是自然科学中基本运算之一，对于超大矩阵的对角化是当今许多科学问题的瓶颈。在应用原子核壳模型理论研究较重的原子核结构时，因为壳模型组态太大，通常的方法是基于各种物理考虑做某些组态截断，另一个思路是利用新的算法和飞速发展的计算机资源对这些大矩阵对角化或者近似对角化。总结了本课题组近年来在壳模型哈密顿量本征值近似方面研究的主要结果，包括最低本征值半经验公式及多种外推方法、本征值与对角元的相关性等。The eigenvalue problem is one of the fundamental issues of sciences. Many research fields have been challenged by diagonalizing huge matrices. The nuclear structure theorists face this problem in studies of medium-heavynuclei in terms of the nuclear shell model, in which the configuration space is too gigantic to handle. Thus one usually truncates the nuclear shell model configuration space based on various considerations. Another approach is to make use of super computers by various algorithms, and/or to obtain approximate eigenvalues. In this paper we review our recent efforts in obtaining approximate eigenvalues of the nuclear shell model Hamiltonian, with the focus on our semi-empirical approach and a number of extrapolation approaches towards predicting the lowest eigenvalue, as well as strong correlation between the sorted eigenvalues and the diagonal matrix elements, and so on.     

Polynitro-Functionalized Dipyrazolo-1,3,5-triazinanes: Energetic Polycyclization toward High Density and Excellent Molecular Stability

A new fused N-heterocyclic framework, dipyrazolo-1,3,5-triazinane, was synthesized and the physiochemical properties of its derivatives were investigated to evaluate the integrated energetic performance. In contrast to 1,3,5-trinitro-1,3,5-triazinane (RDX) featuring a distorted chair confirmation, polynitro-functionalized dipyrazolo-1,3,5-triazinanes have nearly planar backbones, thereby enhancing the density and thermal stability. Among these new energetic tricyclic compounds, 5 a and 12 show favorable crystal densities of 1.937 g cm⁻³ and 1.990 g cm⁻³ at 150 K, respectively, which rank highest in triazinane-based energetic compounds. Additionally, this synthetic approach was carried out to form seven-membered and eight-membered rings, giving rise to tetranitro dipyrazolo-1,3,5-triazepane ( 5 b ) and tetranitro dipyrazolo-1,3,5-triazocane ( 5 c ), respectively.