Alpha decay energies and half-lives for possibly synthesized superheavy elements

We investigate the ground state properties of some superheavy nuclei, which may be synthesized in future experiments. Special emphases are placed on the alpha decay energies and half-lives. The alpha decay energies and half-lives from different theoretical models are compared and discussed comprehensively. Through these calculations and comparisons, the optimal superheavy elements to be synthesized in future experiments are proposed theoretically.     

强耦合的动力学Jahn-Teller效应理论

本文讨论了强耦合情况的、即电子的静态畸变能量大于晶格或分子振动量子能量的情况的动力学Jahn-Teller效应。我们发展了一种适用于强耦合情况的微扰方法,在其中将本征值及本征函数依照电子振动耦合系数的倒数或振动量子能量与静态畸变能量之比展开成幂级数,具体讨论了O_h点群中的Г₈态,求得了电子振动能级。区别于弱耦合情况的特点主要在于:1)虽然并不发生静态畸变,但是振动模的简并性及频谱却都发生了变化;2)如果与电子相耦合的振动模是“调谐”的,则电子及晶格振动的集体运动模将出现,这个理论能被用来解释Weinstock等人所做的关于TcF₆及ReF₆的红外光谱以及Raman光谱的实验结果。     

Studying the Interaction of Pirarubicin with DNA and Determining Pirarubicin in Human Urine Samples: Combining Excitation -Emission Fluorescence Matrices with Second-order Calibration Methods

In this paper, UV–vis spectroscopy and fluorescence were combined to study the binding of Calf thymus DNA (ct-DNA) with the anthacycline antibiotic drug pirarubicin (THP). Ethidium bromide (EB) as the fluorescence probe was used to study the competitive binding interactions of THP with DNA by excitation -emission fluorescence matrices (EEFMs) coupled with the parallel factor analysis (PARAFAC) and the alternating normalization-weighted error algorithm (ANWE) with the second-order advantage. All the results conformed that THP mainly bound with DNA by intercalation. Meanwhile, the two second-order calibration methods have been successfully applied to quantify THP in urine samples. Figures of merit were applied to compare the performance of the two methods. The results presented in this work showed that both the PARAFAC and ANWE methods were the convincing way to be applied in the complex biological systems even in the presence of uncalibrated interferences.     

交联萘沥青的组成与结构特征

萘与硫在较低温度下交联聚合，制得了可溶性好、残炭值高、软化点较低，流动性良好的交联萘沥青。结构分析发现，此沥青分子量分布较窄，主要由三到四个萘分子交联而成，推测其反应机理，估计聚合物经萘环侧位交联成环而形成长链状硫杂环类结构。     

Four Triterpene Oligoglycosides from the seeds of Aesculus Chinensis

TheseedsofAesculuschinensisBge.(Hippocastanaceae)havebeenusedasfolkmedicineforthetreatmentofdistensionandpaininchestandabdomenl.Untilnow,thereisnoreportonitschemicalconstituents.Thispaperdescribesstructureelucidationoftwonewcompounds,escinsIVa3andIVb4onthebasisofspectroscopicmethodsandcomparisonwithescinsla1andfo22.Amongthem,EscinlaIwasstudiedbyX-raydistractionanalysis.Compound3,whitepowder,showediRbandsduetocarboxylanda,p-unsaturatedesterat1740,1713and1640cm-'andstrongabsorptionbandsat34…     

符号和数值混合计算

符号计算和数值计算是两种不同的解决科学和技术发展中问题的计算方法.符号计算可以得到问题精确的完备解,但是计算量大且表达形式往往十分庞大;数值计算可以快速地处理很多实际应用中的问题,但是一般只能得到近似的局部解.特别地,数值计算处理病态问题时,收敛往往较慢且容易出错.着重介绍了符号计算和数值计算之间的密切联系,以及如何运用这两大领域的最新研究成果,探索和开发符号和数值混合计算算法和软件,使之兼备符号计算的完备化和数值计算的高效性.     

广义模糊熵及其诱导的区别度

广义模糊熵是模糊熵在广义模糊补意义下的推广,本文给出广义模糊熵的公理化定义 ,基于σ-广义模糊熵,讨论了广义模糊熵和区别度的相互诱导关系.     

Variable-weighted least-squares support vector machine for multivariate spectral analysis

Multivariate spectral analysis has been widely applied in chemistry and other fields. Spectral data consisting of measurements at hundreds and even thousands of analytical channels can now be obtained in a few seconds. It is widely accepted that before a multivariate regression model is built, a well-performed variable selection can be helpful to improve the predictive ability of the model. In this paper, the concept of traditional wavelength variable selection has been extended and the idea of variable weighting is incorporated into least-squares support vector machine (LS-SVM). A recently proposed global optimization method, particle swarm optimization (PSO) algorithm is used to search for the weights of variables and the hyper-parameters involved in LS-SVM optimizing the training of a calibration set and the prediction of an independent validation set. All the computation process of this method is automatic. Two real data sets are investigated and the results are compared those of PLS, uninformative variable elimination-PLS (UVE-PLS) and LS-SVM models to demonstrate the advantages of the proposed method.     

Quantitative analysis of levodopa, carbidopa and methyldopa in human plasma samples using HPLC-DAD combined with second-order calibration based on alternating trilinear decomposition algorithm

An HPLC method combined with second-order calibration based on alternating trilinear decomposition (ATLD) algorithm has been developed for the quantitative analysis of levodopa (LVD), carbidopa (CBD) and methyldopa (MTD) in human plasma samples. Prior to the analysis of the analytes by ATLD algorithm, three time regions of chromatograms were selected purposely for each analyte to avoid serious collinearity. Although the spectra of these analytes were similar and interferents coeluted with the analytes studied in biological samples, good recoveries of the analytes could be obtained with HPLC-DAD coupled with second-order calibration based on ATLD algorithm, additional benefits are decreasing times of analysis and less solvent consumption. The average recoveries achieved from ATLD with the factor number of 3 (N = 3) were 100.1 ± 2.1, 96.8 ± 1.7 and 104.2 ± 2.6% for LVD, CBD and MTD, respectively. In addition, elliptical joint confidence region (EJCR) tests as well as figures of merit (FOM) were employed to evaluate the accuracy of the method.     

重氮树脂接枝罗丹明B聚合物对酸、碱的响应性

利用重氮树脂(DR)中N2+的光解特性,通过罗丹明(B(RhB))对重氮树脂的接枝反应,得到了染料功能化的接枝聚合物DR-g-RhB,并由傅里叶红外光谱、1H-NMR、紫外-可见吸收光谱和荧光光谱等分析方法确认了产物结构。结果表明DR-g-RhB具有良好的热稳定性,失重5%所对应的温度超过360°C。通过溶液涂敷法形成的薄膜在不同酸碱度溶液中的UV-Vis吸收光谱会随浸入时间产生规律性变化:在pH=7.0的水中,吸光值基本不随时间变化;而在pH=12.0的肼水溶液中,吸光值随时间先下降、再增加;但在酸中则持续增加,而且对盐酸(pH=2.0)的响应比对醋酸(pH=2.3)更灵敏。