Metal–organic framework MIL‐125(Ti) for efficient adsorptive removal of Rhodamine B from aqueous solution

A metal–organic framework material, MIL‐125(Ti), was solvothermally prepared and characterized using X‐ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy and surface area measurements. MIL‐125(Ti) was then used as an adsorbent for Rhodamine B (RhB) removal in aqueous solution. The adsorption kinetics, adsorption mechanism, adsorption isotherm, activation energy and various thermodynamic parameters were studied in detail. The maximum adsorption capacity of MIL‐125(Ti) for RhB was 59.92 mg g^?1. MIL‐125(Ti) appears to be a promising material for RhB adsorption from aqueous solutions. Copyright © 2014 John Wiley & Sons, Ltd.     

广义直觉模糊信息粒度

直觉模糊信息粒度是度量直觉模糊粒结构不确定性的一种重要方法。本文针对直觉模糊信息粒度在度量直觉模糊粒结构上存在的不足进行分析。首先,介绍直觉模糊粒结构距离。其次,改进了基于偏序关系提出的直觉模糊信息粒度的公理化定义,从直觉模糊粒结构距离观点出发,以最细的直觉模糊粒结构为参照物,计算每个直觉模糊粒结构与最细的直觉模糊粒结构之间的距离,距离的值越大,这个直觉模糊粒结构的信息粒度越大。最后,通过例子验证结论的合理性。     

Ultrasonic-microwave assisted synthesis of three-dimensional polyvinyl alcohol carbonate/graphene oxide sponge and studies of surface resistivity and thermal stability

In the article, graphene oxide (GO) was prepared by flake graphite, nitric acid and peroxyacetic acid via the sonochemical method and characterized, and polyvinyl alcohol carbonate/GO composite (PVAC/GO composite) was synthesized by polyvinyl alcohol (PVA), dimethyl carbonate (DMC) and GO via the approach of transesterification in the case of ultrasonic-microwave synergistic effects and characterized, and three-dimensional PVAC/GO sponge (3D PVAC/GO sponge) was manufactured by PVAC/GO composite via the foaming approach and characterized, and the thermal stability and surface resistivity of 3D PVAC/GO sponge were investigated. Based on those, it had been attested that PVAC polymer was structured by DMC and PVA and had the six-membered lactone rings and the ether bonds, and PVAC/GO composite was constituted by 2D GO lattice and PVAC polymer, and 3D PVAC/GO sponge was constructed by PVAC/GO composite, and the surface resistivity of 3D PVAC/GO sponge with 0.00, 0.60, 1.20, 1.80 and 2.40 g of GO were 9.07 × 10⁷, 6.02 × 10⁷, 4.65 × 10⁷, 2.47 × 10⁷ and 1.06 × 107 O/sq, and the thermal stability of 3D PVAC/GO sponge had improved.     

He离子注入对Ge中缺陷行为的影响研究

本文采用以蒙特卡罗方法为基础的SRIM软件模拟He离子注入对Ge中缺陷行为的影响,为高质量GOI(绝缘体上Ge)材料的制备提供理论指导。本文主要模拟了He离子入射角度、能量以及注入剂量对Ge材料损伤程度和溅射产额等的影响。研究表明:入射角度较小时,拖尾效应不明显,有利于避免沟道效应,同时缺陷空位数(DPA)也处于较低水平;能量增大导致离子射程增大,溅射产额减小,离表面越近的Ge中DPA变少,可以实现低DPA GOI材料的制备;离子注入剂量增大导致损伤区域增大且集中,然而更多的He离子聚集在射程附近,能够很好地降低GOI材料的剥离温度。     

A new economical method with eliminated phase-lag and its derivative for problems in chemistry

Journal of Mathematical Chemistry - A new EcoFinDif (Economical Finite Difference) method with eliminated phase-lag and its first derivative, for periodical and/or oscillating initial or boundary...     

琥珀酸构建具有超级电容器性能的混合金属有机骨架

采用简单的溶剂热法合成了混合金属有机骨架材料（MOF （Ni,Co））,然后通过X射线衍射、FT-IR、扫描电子显微镜、X射线光电子能谱和N₂吸附-脱附对制备的材料进行了表征,并进一步研究了其作为超级电容器电极材料的性能。结果表明,具有独特的纳米花状结构的MOF （Ni_1.2Co_0.8）可以提供更多的电活性位点,从而具有优异的电化学性能,在1 A·g^-1时的比电容为850 F·g^-1。同时本研究工作说明MOF （Ni）电极材料在掺杂适量钴元素后,可增强电极内部电子/离子转移,降低活性物质和电解液之间的接触电阻,提高导电性,增强电化学性能。     

Transversality on locally pseudocompact groups

Two non-discrete Hausdorff group topologies \tau and \delta on a group G are called transversal if the least upper bound \tau \vee \delta of \tau and \delta is the discrete topology. In this paper, we discuss the existence of transversal group topologies on locally pseudocompact, locally precompact, or locally compact groups. We prove that each locally pseudocompact, connected topological group satisfies central subgroup paradigm, which gives an affrmative answer to a problem posed by Dikranjan, Tkachenko, and Yaschenko [Topology Appl., 2006, 153:3338-3354]. For a compact normal subgroup K of a locally compact totally disconnected group G, if G admits a transversal group topology, then G/K admits a transversal group topology, which gives a partial answer again to a problem posed by Dikranjan, Tkachenko, and Yaschenko in 2006. Moreover, we characterize some classes of locally compact groups that admit transversal group topologies.     

铁钝化多孔硅的制备及光致发光机理研究

采用水热腐蚀法在相同环境下制备了不同晶型的铁钝化多孔硅样品。同一样品表面具有相似的孔隙结构,不同样品形貌存在差异。在300 nm光激发下,样品发光峰位于618 nm附近,半高宽约为132 nm。傅立叶红外变换光谱显示样品中有强的Si-Si、Si-O-Si、O_<em>y-Si-H_x化学键振动吸收。结果表明,水热腐蚀法制备的铁钝化多孔硅表面形貌与腐蚀过程的局域电极分布关系密切。样品的光致发光行为可归因于量子限制-发光中心作用,并受非桥氧空穴发光中心数量影响。     

Finite-time synchronization of a class of autonomous chaotic systems

Some criteria for achieving the finite-time synchronization of a class of autonomous chaotic systems are derived by the finite-time stability theory and Gerschgorin disc theorem. Numerical simulations are shown to illustrate the effectiveness of the proposed method.     

具斑块迁移的病毒模型的稳定性分析

研究了一类未感染细胞斑在两斑块间迁移的病毒模型.获得了无病平衡点全局稳定性以及地方病平衡点稳定性的充分条件.研究结果表明阈值R <1且感染细胞生成病毒的速度相对小而病毒细胞死亡率足够大时,病毒趋于灭绝;而阈值R> 1且感染细胞生成病毒的速度相对大而病毒细胞死亡率足够小时,病毒持续流行.