用亚铁氰化钛钾从模拟高放废液中吸附Cs研究

本文研究了溶胶-凝胶法合成的无机离子交换剂亚铁氰化钛钾的耐酸性和辐照稳定性等性能，测定了从模拟酸性高放废液中主要常量组分离子相对于Cs的分离系数，研究了流速对Cs吸附曲线的影响。实验结果表明，该交换剂具有良好的辐照稳定性，交换剂经2×106Gy的辐照，亚铁氰化钛钾对Cs的表观交换容量下降6～7％，为0．873mmolCs／g干交换剂。在0．5～1．5mol／LHNO3中具有良好的化学稳定性。在模拟酸性高放废液中对几种离子的选择吸附顺序为：Cs＞＞M＞Fe＞Sr＞Na＞Cr＞Nd，Mn，该交换剂具有较高的吸附容量，对Cs具有良好的选择性，有希望用作从酸性高放废液中去除Cs的材料。     

The Enhancement of Efficiency of High-order Harmonic in Intense Laser Field Based on Asymptotic Boundary Conditions and Symplectic Algorithm

Asymptotic boundary condition (ABC) of laser-atom interaction presented recently is applied to transform the initial value problem of the time-dependent Schrödinger equation (TDSE) in infinite space into the initial and boundary value problem in the finite space, and then the TDSE is discretized into linear canonical equations by substituting the symmetry difference quotient for the 2-order partial derivative. The canonical equation is solved by symplectic algorithm. The ground state and the equal weight coherent superposition of the ground state and the first excited state have been taken as the initial conditions, respectively, while we calculate the population of bound states, the evolution of average distance and the high-order harmonic generation (HHG). The conversion efficiency of HHG can be enhanced by initial coherent superposition state and moderate laser intensities     

Interactions of Some Amino Acids with Aqueous N,N-Dimethylacetamide Solutions at 298.15 and 308.15 K: A Volumetric Approach

The apparent molar volumes, V _φ , of glycine, L-alanine and L-serine were obtained in aqueous 0 to ∼4 mol⋅kg⁻¹ N,N-dimethylacetamide (DMA) solutions from density measurements at 298.15 and 308.15 K. The standard partial molar volume, V _φ ^o, and standard partial molar volumes of transfer, Δ_tr V _φ ^o, were determined for these amino acids. It has been shown that hydrophilic-hydrophilic interactions between charged groups of the amino acids and the —CON= group of DMA are predominant in the case of glycine and L-serine, but for L-alanine the interactions between its side group (—CH₃) and DMA are predominant. An increase in temperature increases the standard partial molar volumes but decreases the transfer volumes of the amino acids. The results have been interpreted in terms of cosphere overlap model.     

Grand challenges in quantum‐classical modeling of molecule–surface interactions

A detailed understanding of the adsorption of small molecules or macromolecules to a materials surface is of importance, for example, in the context of material and biomaterial research. Classical atomistic simulations in principle provide microscopic insight in the complex entropic and enthalpic interplay at the interface. However, an application of classical atomistic simulation techniques to such interface systems is a nontrivial problem, mostly because commonly used force fields cannot be straightforwardly applied, as they are usually developed to reproduce bulk properties of either solids or liquids but not the interfacial region between two phases. Therefore, a dual‐scale modeling approach has often been the method of choice in the past, in which the classical force field is parameterized such that quantum chemical information on near‐surface conformations and adsorption energies is reproduced by the classical force field. We will discuss in this review the current state‐of‐the‐art of quantum‐classical modeling of molecule–surface interactions and outline the major challenges in this field. In this context, we will, among other things, lay emphasis on discussing ways to obtain representable force fields and propose systematic and system‐independent strategies to optimize the quantum‐classical fitting procedure. © 2013 Wiley Periodicals, Inc.     

The effect of ionic strength on the diffusion of 125I in Gaomiaozi bentonite

The diffusion of ¹²⁵I^? in compacted Gaomiaozi (GMZ) bentonite was investigated by capillary in-diffusion method. Apparent and effective diffusion coefficients and accessible porosity of iodide in GMZ bentonite were obtained, and the effect of ionic strength on diffusion parameters was studied. The apparent diffusion coefficients of iodide in compacted GMZ bentonite are in the range of 1.0–6.0 × 10^?10 m² s^?1 under the conditions of dry bulk density 1,500 kg m^?3 and temperature 298 K, and increase with increasing ionic strength. This effect was explained through the analysis of microscopic structure of compacted bentonite. The iodide can only diffuse in unbound interparticle pore solution of compacted bentonite. The apparent diffusion coefficient is a function of accessible porosity which is decided by the thickness of diffusion double layer, and the thickness is in turn controlled by ionic strength.     

A three-layer egg-configurated Bragg microcavity of polyglycerol coated cholesteric-liquid-crystal encapsulated by hollow-glass-microsphere

ABSTRACT

This letter reports the optical pumped lasing behaviours of a three-layer Bragg resonance cavity consisting of dye-doped cholesteric liquid crystal (DDCLC) microdroplet, polyglycerol-2 and hollow glass microsphere. The function of PG2 is to control the parallel anchoring of the liquid crystal (LC) molecules on the surface of the LC microdroplet. The whispering-gallery mode (WGM), radial Bragg (photonic bandgap, PBG) mode and Bragg WGM (BWGM) are observed in DDCLC microspheres with different helical pitches and LC refractive indices. The formation mechanisms of six types of lasing emission conditions are analysed in detail. The study results present the prospect of controlling the output mode of the laser. Furthermore, such solid shell-based DDCLC microspheres have outstanding potential applications in miniaturised 3D Bragg lasers, sensors, and integrated and tunable optical devices.     

Synthesis and Antitumor Evaluation of Novel Hybrids of Phenylsulfonylfuroxan and Estradiol Derivatives

Fifteen novel furoxan-based nitric oxide (NO) releasing hybrids of estradiol derivatives were synthesized and evaluated in vitro anti-proliferative activity in MDA-MB-231, A2780, Hela and HUVEC cell lines. Most of them displayed potent anti-proliferative effects. Among the compounds, 4-bromo-3-((phenylsulfonyl)-1,2,5-oxadiazole 2-oxide)-oxy-propoxy-estradiol ( 11 b ) exhibited the best activity with IC₅₀ values of 3.58–0.0008 μM. Preliminary pharmacological studies showed that 11 b induced apoptosis and hardly affected the cell cycle of MDA-MB-231 cell line. NO-releasing capacity and inhibition of ERK/MAPK pathway signaling might explain the potent antineoplastic activity of these compounds. The preliminary structure-activity relationship (SAR) showed that steroidal scaffolds with a linker in 3-position were favorable moieties to evidently increase the bioactivities of these hybrids. Overall, these results implied that 11 b merited to be further investigated as a promising anti-cancer candidate.     

缺中子Np新核素的α衰变研究

合成远离稳定线的新核素、探索原子核存在的极限是目前核物理研究的重要课题。在中子壳N=126的最丰质子一侧,极端缺中子的超铀核素处于质子滴线和中子壳的交叉位置,合成和研究该核区核素对研究N=126壳结构的演化性质具有重要意义。基于兰州重离子加速器上的充气反冲核谱仪装置(SHANS),利用36,40Ar+185,187Re熔合蒸发反应,合成了极缺中子的219,220,223,224Np新核素,在中子壳N=126附近首次建立了Np同位素链的$ \alpha$衰变系统性,获得了N=126壳效应在Np同位素链中依然存在的实验证据。依据单质子分离能的系统性分析,确定了Np同位素链中质子滴线的位置,219Np也成为目前已知的最重的质子滴线外核素。此外,基于实验测量的反应截面,并与理论模型的计算结果相比较,讨论了进一步合成该核区其它新核素218,221,222Np的可行性。     

Competition of spiral waves in heterogeneous CGLE systems

Nonlinear Dynamics - The effects of spatial heterogeneity on a two-dimensional complex Ginzburg–Landau equation model are studied. In general, the interaction of a pair of spiral waves with a...     

高放废物地质处置中的模型

我国将采用深地质处置的方法处理核能发展所产生的大量高水平放射性废物。为了准确地预测核素的迁移行为,评估处置库的安全性,除了实验之外,还必须使用模型。本文对高放废物地质处置中所涉及的模型,以及与模型相关的软件、数据库做了综述,重点叙述了用于化学种态分析的地球化学模型,扼要介绍了多场耦合模型。此外还简要报告了本实验室核素迁移实验数据的处理方法和程序。