中药丹参及其近缘种中微量元素的主成分和聚类分析

采用原子吸收光谱法测定了不同产地的中药丹参及其近缘种植物白花丹参、雪山鼠尾草、云南鼠尾草、甘西鼠尾草、贵州鼠尾草、血盆草、粘毛鼠尾草、峨眉鼠尾草、黄鼠狼花、短唇鼠尾草和犬形鼠尾草中的Cu,Zn,Fe,Mg,Ca,Cr,Pb,Mo,Mn和Cd共10种微量元素的含量,应用主成分和聚类分析法对测定结果进行了研究。经过主成分分析得出3个主因子,其累计方差贡献率达79.3%。第一主因子的方差贡献率为49.6%,故所对应的Fe,Mn,Cu,Zn,Cd和Pb是丹参及其近缘种的特征元素。聚类分析将21个样品聚成2组,除浙江栽培丹参和白花丹参外,来自不同产地的9个丹参样品聚为一组;除贵州鼠尾草外,其他鼠尾草样品聚在一起,故此法可以将丹参和鼠尾草属其他植物区分开,总符合率达90%。因此利用原子吸收光谱法测定丹参及其近缘种中微量元素含量并对测定结果进行聚类分析是鉴别正品丹参的一种快速、准确的方法。     

阴离子交换离子色谱法测定乳酸催化制备的丙烯酸

通过乳酸催化脱水制备丙烯酸具有良好的应用前景。为了对其中的催化过程进行有效、及时的监控,建立了一种同时测定乳酸及丙烯酸的阴离子交换色谱法(AEC)。选择Metrohm A Supp 5阴离子交换柱(150 mm×4.0 mm),以2 mmol/L Na2CO3+2 mmol/L NaHCO3混合水溶液为流动相,采用化学抑制电导检测技术,乳酸和丙烯酸在6 min内即可实现完全分离。乳酸和丙烯酸工作曲线的线性范围分别为0.1～500 mg/L和0.1～200 mg/L,检出限分别为0.030 mg/L和0.035 mg/L,加标回收率分别为100.7%～106%和99.6%～103%,相对标准偏差分别为2.16%~2.49%和2.42%~2.48%。该方法准确、快速、灵敏、重现性好。     

磷扩散法制备高掺磷p型ZnO薄膜的磁控溅射工艺的探索

在前期通过n+-Si衬底中的磷向沉积于其上面的ZnO薄膜的扩散制备高掺磷p型ZnO薄膜的研究基础上,探索了较有普遍应用意义的扩散法制备p型ZnO薄膜的磁控溅射工艺.结果表明,当磁控溅射的氧氩质量流量比与衬底温度满足特定的低阶指数函数的匹配关系时,所制备的ZnO薄膜为p型,而且薄膜中磷原子的深度分布是均匀的;另外,这种薄膜的厚度随着氧氩流量比的增加而减小,而薄膜中氧锌原子浓度比都大于1,比值大小与氧氩质量流量比和衬底温度有关.     

载Ag二氧化钛纳米线的制备及其光催化性能

利用水热合成法,制备出了二氧化钛纳米线,通过葡萄糖还原Ag(NH3)+2,在制备出的二氧化钛纳米线表面负载了 Ag纳米颗粒.利用透射电镜(TEM)、高分辨透射电镜(HRTEM)、X射线光电子能谱(XPS)和紫外-可见光谱(UV-Vis)对产物进行了表征.结果表明:该Ag/TiO2纳米线在可见光区域表现出较强的吸收性能.测试了样品降解酸性红3R溶液的活性.结果表明,TiO2纳米线表面负载Ag纳米颗粒对提高其光催化性能具有积极的作用.     

Kinetics and Thermodynamics of Adsorption of VB12 onto Mesoporous Carbon Coated with PMMA

Ordered mesoporous carbons CMK-3, CMK-1 coated with poly(methyl methacrylate)(PMMA)(CMK-3- PMMA and CMK-1-PMMA) and pristine mesoporous carbons CMK-3, CMK-1 were employed to adsorb vitamin B12(VB12) from water solution. Adsorption isotherm and kinetics of adsorption were investigated via batch experi- ments. It was found that the adsorption capacity of VB12 at 30, 40 and 50 °C can reach 688.2, 572.4 and 428.7 mg/g, respectively. The adsorption isotherm can be described by Langmuir model. The pseudo first- and second-order kinetic models were employed to fit the dynamic adsorption. It was found that the dynamic adsorption follows the pseudo second-order model. The thermodynamic equilibrium coefficients obtained at different temperatures were used to evaluate the thermodynamic constants ΔG0, ΔH0 and ΔS0. The negative value of Gibbs free energy, ΔG0 indicates that the adsorption occurred via a spontaneous process. The increase in the value of –ΔG0 with increasing temperature indicates that higher temperatures were favourable to the sorption process. The enthalpy values of ΔH040 kJ/mol(66.36 kJ/mol and 56.43 kJ/mol) for CMK-3-PMMA and CMK-1-PMMA confirm that chemisorption were involved in the adsorption process. This is consistent with the IR spectra and is another evidence for the formation of hydrogen bond between PMMA in the pore of CMK-3 and VB12.     

大范围区域复杂地形风场数值模拟研究

在具复杂地形地貌区域架设桥梁,首要解决的问题是风环境参数的问题.本文针对某一具有复杂地形地貌的大范围区域(区域大小23km×27km)复杂地形的风环境进行了数值模拟研究.基于地理信息处理系统(GIS)中的数字地面模型所获得的高程数据,通过逆向工程软件IMAGEWARE及流体动力学建模软件Gambit完成了流体网格的建模工作,对其整体和局部的流场(内层区域的速度场、压力场,越山流动迹线及监控点处的风剖面等)进行了分析,同时对不同的网格划分方式也进行了分析比较.本文的工作也为今后同类大范围区域风场模拟提供了参考.除此之外,用逆向工程软件IMAGEWARE也为今后大尺度区域建模提供了一种新思路.     

145Er的β延发质子衰变性质研究

通过92Mo(58Ni, 2p3n)熔合蒸发反应生成了非常缺中子核145Er。利用氦喷嘴带传输系统把研究目标核传输到低本底测量站, 进行了质子 γ符合测量, 得到了不受同量异位素干扰的145Er的β延发质子谱。经过仔细分析与延发质子符合的γ谱, 发现了145Er的11/2-同核异能态具有β延发质子衰变性质。经拟合退激144Dy不同激发态γ跃迁的衰变曲线, 得出145Er的1/2+基态和11/2-同核异能态的半衰期分别为(1.6±0.6)和(0.6±0.1) s。最后, 简单介绍了中重质量区缺中子新核素的合成及衰变研究计划。The neutron deficient isotope 145Er was produced via the fusion evaporation reaction 92Mo(58Ni, 2p3n). The reaction products were transported to a low background counting area using a He jet tape transport system, and proton γ coincidence measurements were carried out. Based on the analysis of γ transitions in coincidence with β delayed protons, the β delayed proton decay of an νh11/2 isomer in 145Er was proposed. By fitting the decay curves of the γ transitions depopulating the low lying states in 144Dy, the half lives of the ground state and the νh11/2 isomeric state in 145Er were deduced to be (1.6±0.6) and (0.6±0.1) s, respectively. An experimental plan to synthesize new β delayed proton precursors in the medium heavy mass region has been presented.     

\bar{K} Condensation in Neutron Star Matter with Δ Quartet

In the framework of relativistic mean field theory, the condensations of K^- and \bar{K}⁰ in neutron star matter including baryon octet and Δ quartet are studied. We find that in this case K^- and \bar{K}⁰ condensations canoccur at relative shallow optical potential depth of \bar{K} from -80 MeV to -160 MeV. Both K^- and \bar{K}⁰ condensations favor the appearances of Δ resonances. With \bar{K} condensations all the Δ quartet can appear well inside the maximum mass stars. The appearances of Δ resonances change the composition and distribution of particles at high densities. The populations ofΔ resonances can enhance K^- condensation. It is found that in the core of massive neutron stars, neutron star matter includes rich particle species, such as antikaons, baryon octet, and Δ quartet. In the presence of Δ resonances and \bar{K} condensation, the EOS becomes softer and results in smaller maximum mass stars. Furthermore the impact of antikaon condensations,hyperons, and Δ resonances on direct Urca process with nucleons is also discussed briefly.     

脉冲偏压占空比对多孔氧化硅薄膜性质的影响

采用由脉冲负偏压调节的等离子体增强化学气相沉积方法,以硅烷为源气体,在玻璃基片上沉积得到了多孔二氧化硅薄膜。将反应过程中加在沉积区域的脉冲偏压固定在-350V,当占空比从0.162增大到0.864时,薄膜样品的形貌、成份和结构均不相同。扫描电镜照片表明,组成多孔氧化硅薄膜的颗粒在占空比增大时变得细腻,并且薄膜整体变得多孔且蓬松。拉曼光谱和红外光谱结果显示,薄膜样品中的非晶硅和Si-H键在较高的占空比下减弱甚至消失。占空比升高时氧化硅桥键所占比例持续增加。     

粒子群优化算法在光纤光栅传感器波长解调中的应用

为了提高光纤光栅(FBG)解调系统的波长解调精度,采用粒子群优化(PSO)算法结合参考光纤光栅(FBG),对常用波长解调器Fabry-Perot型光纤滤波器(FPF)的透射光谱中心波长与控制电压之间存在的非线性和回滞特性进行了研究,并提出一种实时建立FPF透射光中心波长与其控制电压之间关系模型的方法。该方法利用粒子群优化算法收敛快、易实现的特点,保证了FPF模型建立的准确性和实时性。实验结果证明,利用所建模型可有效提高FBG传感系统的波长测量准确度,测量误差不超过25 pm。系统结构简单,对提高FBG传感系统的测量准确度具有重要意义。