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。     

Metal-Enhanced S(2) Fluorescence from Azulene

In this paper, we report the first observation of metal-enhanced S(2) emission at room and low temperature (77K). The S(2) emission intensity of Azulene is enhanced by close proximity to Silver island films (SiFs). In this regard, a ≈ 2-fold higher S(2) fluorescence intensity of Azulene was observed from SiFs as compared to a glass control sample. This suggests that S(2) excited states can couple to surface plasmons and enhance S(2) fluorescence yields, a helpful observation in our understanding the interactions between plasmons and lumophores, and our continued efforts to develop a unified plasmon-lumophore/fluorophore theory.     

铜基串联催化剂电催化CO2还原的研究进展

化石燃料的燃烧和其他人类活动排放了大量的CO₂气体,引发了诸多环境问题。电催化CO₂还原反应(CO₂RR)可以储存间歇可再生能源,实现人为闭合碳循环,被认为是获得高附加值化学品和燃料的有效途径。电催化CO₂RR涉及多个电子-质子转移步骤,其中^*CO通常被认为是关键中间体。铜由于对^*CO具有合适的吸附能,已被广泛证明是唯一能够有效地将CO₂还原为碳氢化合物和含氧化合物的金属催化剂。然而,纯Cu稳定性差、产品选择性低、过电位高,阻碍了工业级多碳产品的生产。构筑Cu基串联催化剂是提高CO₂RR性能的一种有前途的策略。本文首先介绍电催化CO₂RR的反应路线和串联机理。然后,系统地总结铜基串联催化剂对电催化CO₂RR的最新研究进展。最后,提出合理设计和可控合成新型电催化CO₂RR串联催化剂面临的挑战和机遇。     

Low Temperature Metal-Enhanced Fluorescence

In this short letter, we describe the effects of low temperature on the Metal-Enhanced Fluorescence (MEF) phenomenon. Fluorophores close to Silver Island Films (SiFs) show on average two- to ten-fold enhancements in their fluorescence signatures at room temperature. However, at 77 K, we have observed that MEF is even more pronounced as compared to an identical glass control sample. We also demonstrate that the further enhancements in MEF occur at low temperature over a range of visible wavelengths for different fluorophores, for both SiFs and 20 nm surface deposited gold colloids.     

Design of diamond-shape photonic crystal fiber polarization filter based on surface plasma resonance effect

A novel plasmonic polarization filter based on the diamond-shape photonic crystal fiber(PCF) is proposed. The resonant coupling characteristics of the PCF polarization filter are investigated by the full-vector finite-element method. By optimizing the geometric parameters of the PCF, when the fiber length is 5 mm, the polarization filter has a bandwidth of 990 nm and an extinction ratio(ER) of lower than -20 dB. Moreover, a single wavelength polarization filter can also be achieved, along with an ER of -279.78 dB at wavelength 1.55 μm. It is believed that the proposed PCF polarization filter will be very useful in laser and optical communication systems.     

One‐Step Hydrothermal Synthesis of Nitrogen‐Doped Carbon Nanotubes as an Efficient Electrocatalyst for Oxygen Reduction Reactions

A high amount of heteroatom doping in carbon, although favorable for enhanced density of catalytically active sites, may lead to substantially decreased electroconductivity, which is necessary for the electrochemical oxygen reduction reaction. Herein, a relatively low amount of nitrogen was successfully doped into carbon nanotubes (CNTs) by a hydrothermal approach in one step, and the synthesized nitrogen‐doped CNT (CNT‐N) materials retained most of the original, excellent characteristics, such as the graphitic structure, tubular morphology, and high surface area, of CNTs. The resultant CNT‐N materials, although containing a relatively low amount of nitrogen doping, exhibited high electrocatalytic ORR activity, comparable to that of 20 wt % Pt/C; long durability; and, more importantly, largely inhibited methanol crossover effect.     

CE determination of quinolones in the presence of bovine serum albumin

This article describes the influence of bovine serum albumin (BSA) as an additive on the capillary electrophoresis–potential gradient determination of five quinolones, enoxacin, norfloxacin, ofloxacin, fleroxacin, and pazufloxacin. With 10 mg/L of BSA present in the buffer of 30 mM Tris and 3 mM phosphoric acid at pH 9, the detection limits of the five quinolones were in the range of 0.24–0.68 mg/L, i. e. 5.8–16.5‐fold lower than those obtained with the buffer devoid of BSA, and the analysis time was shortened. We suggest that the inner wall‐adsorbed BSA suppresses the adsorption of quinolones and simultaneously enhances the electroosmotic flow rate. Our experiments indicated that adopting the potential gradient detection technique could eliminate the interference of the UV‐active proteins on the detection of quinolones that would occur with conventional optical detection, and therefore offer high detection sensitivity. As a demonstration, the method was applied to the determination of QNs in fortified chicken muscle sample with satisfactory results.     

平面三次Pythagorean-Hodograph Hyperbolic曲线

本文基于Pythagorean-hodograph (PH)曲线和代数双曲线的良好几何特性,构造了Pythagorean-Hodograph Hyperbolic (PH-H)曲线,并给出了PH-H曲线的定义以及相应性质.同时,分别利用Hyperbolic基函数和Algebraic Hyperbolic (AH) B\''ezier基函数,得到了平面三次AH B\''ezier曲线为PH曲线的两个不同的充要条件.此外,三次PH-H曲线也被用于求解具有确定解的$G^1$ Hermite插值问题.文中给出了具体实例来说明我们的方法.     

On the Reconstruction of the Sturm-Liouville Problems with Spectral Parameter in the Discontinuity Conditions

In this paper, we are concerned with the problem of recovering the Sturm–Liouville problem under the circumstance of the discontinuity conditions involved spectral parameter at finite interior points of a finite interval. We provide procedures for constructing their potentials and boundary conditions either from the Weyl function, or from spectral data, or from two spectra in terms of the method of spectral mappings.