第三族金属氧化物离子对二氧化碳转化的红外光谱研究

本文利用红外光解离光谱研究了第三族金属氧化物离子对二氧化碳分子的转化机制. 研究表明,对于[ScO(CO₂)_n]⁺体系,在n≤4时,形成了溶剂化结构;在n=5时,形成了碳酸盐结构,实现了二氧化碳的转化. 对于[YO(CO₂)_n]⁺体系,需要4个二氧化碳分子就可以实现二氧化碳的转化. 而在[YO(CO₂)_n]⁺体系中,只发现了溶剂化结构,没有观察到碳酸盐结构. 理论计算表明,[YO(CO₂)_n]⁺体系拥有最小的溶剂化结构向碳酸盐结构转化能垒,[LaO(CO₂)_n]⁺体系拥有最大的溶剂化结构向碳酸盐结构转化能垒. 本文从分子水平揭示了不同金属氧化物离子对二氧化碳分子转化的影响规律.     

Nanostructured Polyelectrolyte-based System as a Toolbox for Metal Ions Detection

The capability of certain heavy metal ions to induce fluorescence decrease by a quenching mechanism suggested us to design and build a sensor potentially tunable for different ions at different concentrations. We propose a quenching-based sensor exploiting a nanostructured architecture in which fluorescent molecules (the sensing probe) are entrapped to recognize a specific analyte (heavy metal ions) through an optical transduction. The polyelectrolyte nanostructured system, named nanocapsule, improves the fluorophore-ion quenching sensitivity allowing a micromolar detection. Furthermore we couple our sensor with an electrical device in order to refine the sensing procedure: the electric field created allows a metal ions spatial gradient, necessary to detect a specific element on a single sample solution, avoiding a comparative analysis with an intensity reference value. Results obtained will show the advantages and the potentialities of our system as a smart toolbox for metal ions detection.     

一类n维非球谐振子势的精确解

严格求解一类n维非球谐振子势的定态薛定谔方程，获得了归一化径向波函数和能谱的 精确解.在此基础上导出径向矩阵元r,L_n｜r^s｜n′ ₄,L′_n>的通项公式. 关键词： n维非球谐振子 精确解 径向矩阵元 通项公式     

ICP—AES法中稀土元素间的相互干扰研究

稀土元素的谱线较复杂,相互间存在着不同程度的干扰。本文着重研究了ＩＣＰ－ＡＥＳ法中,它们间的干扰情况,并用几种校正方法进行了比较。     

Quellenformen für γ-Bestrahlungsanlagen mit Reaktorbrennelementen

Wesentliche Bedeutung für die Strahlenausnutzung in γ-Bestrahlungsanlagen mit Reaktorbrennelementen hat die Quellenform, wobei der besonderen Quelldichteverteilung Rechnung zu tragen ist. Es wurden Bewertungskenngröβen abgeleitet, mit deren Hilfe Optimalvarianten der Quellenform für verschiedene Bestrahlgutbedingungen bestimmt werden können. Für fünf Quellen-grundformen sind Formeln zur Berechnung der Strahlenfelder angegeben. Mit Hilfe der ermittelten Kenngröβen wurden die verschiedensten Quellenformen verglichen. Die hieraus abgeleiteten Optimalbedingungen sind abschlieβend zusammengefaβt.     

Der Einsatz von Sorbentien räumlich-globulrer Struktur zur Abtrennung radioaktiver Verunreinigungen aus Wasser

Abstract

Possibilities of using a new generation of sorbents have been investigated. Polymers of spatial-globular (spherulitic) structure (RGS polymers) have been tested to separate Cs, Sr and rare earth elements – which can also be radioactive contaminants – from different waters.

RGS polymers are both, solids and highly-disperse systems being extremely permeable to fluids and gases with low pressure decline. They were currently used to clean industrial waste-water.

It is shown that these polymers can be used successfully to separate radionuclides. Polymers RGS-81 and RGS-112 have high distribution coefficients for CS, Sr, Sc, the lanthanide series and Hf in weakly acid solutions. In HF solutions, Sc and Hf can be separated from Cs, Sr and the lanthanides.     

Recovery of low temperature electron irradiation-induced damage in n-type gaas

Undoped n-type GaAa was irradiated near 5 and 77 °K with electrons having incident energies between 0.46 and 1.30 MeV. The recovery of the electrical resistivity and the Hall coefficient upon annealing from 4 to 520 °K was monitored. Changes which occurred upon annealing below 200 °K could be reversed by ionizing radiation. A small amount of irreversible ionization-induced recovery was observed after irradiation near 5 °K. Major irreversible recovery stages were centered near 235 (stage I), 280 (stage II) and 520 °K (stage III). Recovery in stage I and II obeyed first order kinetics. The activation energies of stages I and II were determined as 0.72 and 0.83 eV, respectively. The carrier concentration changes per unit irradiation dose corresponding to the three recovery stages differed in their energy dependence indicating that the defects which are removed in stage III have the lowest threshold energy. The carrier concentration changes per unit irradiation dose corresponding to stages I and III were higher for irradiation near 5 °K than for irradiation near 77 °K.     

Early transition metal dopants in cuprous oxide: To spin or not to spin

We present a trend study of a large variety of dopants at the cation site in Cu₂O (i.e. substituting Cu), focussing largely on the early 3d-, 4d-, and 5d-transition metals (TMs) in which many of them are known to be non-magnetic. We also include s-, sp- and d¹⁰-metals for comparison. We find that doping with sp-elements results in zero spin moment while dopants with a partially filled d-band show a stronger tendency to magnetize and 3d-TM dopants exhibit a larger magnetic moment than most of the 4d- and 5d-TM dopants. From this trend study, we also find a correlation between their substitution enthalpy and associated interatomic relaxations. In particular, Ti-doped Cu₂O appears to be an interesting system, given its “peculiar” ability to exhibit a spin moment when doped with a non-magnetic substituent like Ti. We also find that the interaction between two doped Ti atoms in Ti₂:Cu₂O is predominantly antiferromagnetic, and interestingly (and unexpectedly), this interaction rapidly declines as a function of inter-dopant distance, as in the case for the magnetic late-TM dopants like Co₂:Cu₂O.     

机械抛光铜金属表面对罗丹明的荧光增强效应

应用激光光谱学方法,研究了铜表面Rh6G分子的荧光增强效应对于金属衬底表面所形成的氧化层的依赖关系,探索了由于空气氧化而形成的氧化层在表面荧光增强效应中的重要意义和作用机理.实验采用罗丹明6G荧光探针分子,在532 nm连续光激发下,研究机械抛光铜金属衬底在经历不同氧化时间,对吸附其表面的Rh6G分子的荧光增强效果.研究结果表明,适当控制金属样品表面的氧化时间,金属铜表面对若丹明分子的荧光发射表现出猝灭和增强效应.金属氧化层起到了隔离荧光分子与金属表面的作用,减弱了由于激发态荧光分子向金属转移非辐射能量和在金属表面诱导反向偶极子而产生的荧光猝灭效应,从而提高了纯金属铜表面荧光增强辐射行为.因此在微纳金属衬底的荧光增强效应研究中,采用适当的实验手段,精确控制隔离层间距,是表面增强光谱获取的重要途径之一.     

忆阻器、忆容器和忆感器的Simulink建模及其特性分析

忆阻器、忆容器和忆感器均是具有记忆特性的新型非线性电路元件,也被称为记忆元件.以三种电路元件的通用数学模型为依据,从数学分析的角度,对忆阻器、忆容器和忆感器的Simulink模型进行了建立.在Simulink模型中体现了记忆元件对历史状态和系统状态变量的依赖性,正确表现出其独特的记忆特性.通过一系列仿真分析,得到了忆阻器、忆容器和忆感器的元件特性,验证了模型的有效性.此外,通过对三者在不同参数、不同激励下的电路特性分析,得到了三种记忆元件等效模型随频率和幅值变化的规律,为以后忆阻器、忆容器和忆感器基于Simulink的仿真研究和应用研究奠定基础.