Supplier selection using axiomatic fuzzy set and TOPSIS methodology in supply chain management

The current paper presents a comprehensive methodology for supplier selection. In the first stage, the linguistic values expressed as trapezoidal fuzzy numbers are used to assess the weights of the criteria. The Axiomatic Fuzzy Set clustering (AFS) method, which handles ambiguity and fuzziness in the supplier selection problem effectively, is applied to cluster the suppliers and evaluate each potential supplier that aims at obtaining initial supplier ranking. In the second stage, the Fuzzy Analytic Hierarchy Process (FAHP) model is constructed to determine the weight of various quantitative and qualitative criteria. To address multiple decision criteria in supplier ranking, the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) is employed to select the final suppliers. A numerical example composed of 30 suppliers and 6 criteria is studied, and the experimental results show that the proposed evaluation framework is suitable for supplier selection decisions even with the dependent criteria/attributes.     

Monolithic enantiomer-selective stationary phases for capillary electrochromatography

Monolithic materials have become a well-established format for stationary phases in the field of capillary electrochromatography. Four types of monoliths, namely particle-fixed, silica-based, polymer-based, and molecularly imprinted monoliths, have been utilized as enantiomer-selective stationary phases in CEC. This review summarizes recent developments in the area of monolithic enantiomer-selective stationary phases for CEC. The preparative procedure and the characterization of these columns are highlighted. In addition, the disadvantages and limitations of different monolithic enantiomer-selective stationary phases in CEC are briefly discussed.     

稀土金属间化合物CeSn_3和CeIn_3的能带理论

本文报道了CeSn, 和Celn_3 的能带计算结果. 对其f 电子的行为, 以及f 电子与非f 原子的s, p , d 电子之间的杂化进行了讨论. 分析了费密能级附近的态密度分布及能带结构. 关键词：     

二元光学元件衍射效率的逐层分析法研究

提出了一种有效的分析二元光学元件衍射效率的新方法－逐层分析法，并对四台阶二元器件，就蚀刻深度误差和横向对准误差对器件衍射效率的影响进行了详细的分析和讨论，证明了用该方法分析含有横向对准误差的二元光学元件的衍射效率非常简便有效。     

10Gb/s单信道光纤传输系统性能仿真研究

光纤传输系统的优化设计是光纤通信质量的重要保证.本文基于光子传输设计套件(PTDS)软件平台,对光纤传输系统的传输特性作了大量仿真研究,并得出分析了一些重要参量如光纤长度,光纤的损耗和衰减,光功率大小等对光传输系统的影响规律,给出了相应的补偿措施.本文研究结果对优化光纤传输系统有一定的参考价值.     

两种外磁场形式对介质面次级电子倍增的抑制

利用自编1D3V PIC程序,数值研究了不同外加磁场方式对次级电子倍增抑制的物理过程,给出了次级电子数目、平均能量、密度、运动轨迹、渡越时间、介质表面静电场及沉积功率等物理量时空分布关系。模拟结果表明：不同方向外加磁场抑制次级电子倍增的机理有所不同。轴向外加磁场利用电子回旋运动干扰微波电场对电子加速过程,使其碰壁能量降低以达到抑制二次电子倍增的效果;横向外加磁场利用电子回旋漂移过程中,电子半个周期被推离介质表面（不发生次级电子倍增）,半个周期被推回介质表面（降低电子碰撞能量）的作用机理,达到抑制二次电子倍增的效果。讨论了横向磁场在回旋共振下,电子回旋同步加速导致回旋半径增大,电子能量持续增加的特殊过程。两种外加磁场方式都可以通过增加磁场达到进一步抑制次级电子倍增的目的。轴向外加磁场加载容易,但对磁场要求较高;横向外加磁场需要磁场较低,但加载较为困难。     

Determination of ionization constants of saccharides by capillary zone electrophoresis with amperometric detection

Summary A method based on a linear model enabling the efficient determination of the ionization constants (K _a) of saccharides by capillary zone electrophoresis with amperometric detection has been demonstrated. TheK _a values obtained from the plots of the reciprocal effective mobility against the inverse concentration of sodium hydroxide were in agreement with literature values.     

Polymeric (μ2‐nitrato‐κ2O:O′)(μ2‐nitrato‐κ2O:O)(μ4‐pyridinium‐4‐thiol­ato‐κ4S:S:S:S)­disilver(I)

The title compound, [Ag₂(NO₃)₂(C₅H₅NS)]_n, was obtained from the reaction of silver nitrate with bis(4‐pyridyl) disufide (4‐PDS) in a mixture of ethanol and water, which suggests that the di­sulfide bond of 4‐PDS can be cleaved under mild conditions. The structure of the title compound is a two‐dimensional infinite array in which the asymmetric unit contains two Ag atoms, a pyridinium‐4‐thiol­ate mol­ecule and two nitrate groups. Each pyridinium‐4‐thiol­ate mol­ecule acts as a μ₄ bridge, linking four Ag atoms, with Ag—S bond distances of 2.4870 (19), 2.5791 (19), 2.5992 (19) and 2.848 (2) Å. The Ag⋯Ag distances lie in the range 2.889 (2)–3.049 (1) Å.     

掺铝Co_3O_4的制备及其电容性能研究

以KOH作沉淀剂制备掺杂Al(Ⅲ)的Co3O4粉体.X射线衍射显示,掺Al的Co3O4不改变其晶型结构.循环伏安、恒流充放电等测试表明,化学掺Al后的Co3O4电极,其比容量提高,当Co(Ⅱ)与Al(Ⅲ)的摩尔比为1∶0.05时,在0~400 mV的电位区间内,5 mA/cm2电流密度下,单电极放电比容量可达518.07 F/g.     

高效液相色谱法测定茶叶中游离糖的含量

1引言 茶叶中的游离糖不仅是构成茶叶滋味的主要成分,给茶汤带来甜醇的味道,而且在茶叶加工过程中可发生非酶促褐变作用,生成相应的醛类和吡咯类、吡嗪类等含氮化合物,因而对于茶叶的色泽和香气的形成有重要影响.