Fully Reversible Homogeneous and Heterogeneous Li Storage in RuO2 with High Capacity

In this paper, we report that Li can be stored in RuO₂ with an unusually high coulombic efficiency. The process involves three electrochemical steps: i) formation of a Ru/Li₂O nanocomposite, ii) formation of a Li‐containing surface film, and iii) interfacial deposition of Li within the Ru/Li₂O matrix. Corresponding to the storage of 5.6 mole of Li ions per mole of RuO₂, a high capacity of 1130 mAh g^–1 is achieved. Furthermore, virtually all inserted Li ions can be extracted, corresponding to a nearly 100 % coulombic efficiency at the first cycle. Achieving a complete reversibility for such a Li storage system through complex heterogeneous solid‐state electrochemical reactions is possible because of the formation of nanoscale Ru/Li₂O during Li insertion and nano‐RuO₂ during Li extraction, in addition to the favorable transport properties of RuO₂ itself.     

1.3μm光学环行器正向损耗及反向隔离比的理论及实验研究

在理论及实验上分析了影响光环行器插入损耗及反向隔离比的因素,讨论了环行器中起、检偏镜参数对其性能的影响.结果表明,起、检偏镜的各组参数存在最佳选择,以保证环行器具有低插损、高隔离比及与偏振无关的特性.作者研制的环行器正向损耗小于1dB,反向隔离比在25.5dB与28dB之间.     

Analysis of the performance of the parallel quicksort method

In this paper a theoretical analysis of the performance of a parallel form of the Quicksort algorithm is presented and shown to be in qualitative agreement with experiments carried out on the Loughborough University NEPTUNE parallel system.     

Electrochemical lithium and sodium intercalation into TaFe1.25Te3

Lithium and sodium have been topotactically inserted in the lattice of TaFe_1.25Te₃ by electrochemical procedures. The existence of electronically unequivalent sites occupied by tellurium atoms conditions a two-step insertion process. In each step, the alkali metal ions occupy empty sites in the structure which are coordinated by tellurium atoms of a different set of sites. The␣thermodynamic and kinetic parameters of Li _x TaFe_1.25Te₃ and Na _x TaFe_1.25Te₃ have been determined and compared with other inserted binary and ternary chalcogenides. The values of the free energy of intercalation are less negative than those previously reported for TaTe₂ and close to those found for the misfit layer compound (PbS)_1.13TaS₂. The values of alkali metal ion diffusivity are closer to those reported for the binary telluride, due to the similarities in the atoms exposed to the interlayer space. Received: 14 October 1997 / Accepted: 14 November 1997     

FMS—1光纤固定连接器在单模光缆线路上的应用

本文介绍ＦＭＳ—１型光纤固定连接器在四条单模光缆线路中现场接续情况。四条光缆线路共用１５４只接头，平均接续损耗０．１２５ｄＢ，每根光纤的平均接头损耗≤０．１５ｄＢ。最长接续巨离３３ｋｍ。文中还对青阳至九华山段测量了全部接头的回波损耗，测量结果表明回波损耗大于３８ｄＢ。     

无绳电话用声表面波滤波器

本文讨论了研制的两种无绳电话机用声表面波滤波器，中心频率为４６．５７ＭＨｚ和４９．９ＭＨｚ；△ｆ＿（－３ｄＢ）＝１．７ＭＨＺ；插损≤１０ｄＢ；△ｆ＿（－４０ｄＢ）／△ｆ＿（－３ｄＢ）≤３．５；阻带抑制≤－４０ｄＢ。采用了低插损的三换能器结构。输入叉指换能器采用了波阵面均匀的孔径加权和相位加权，减小了变迹损耗。理论计算与实验结果一致。     

Insertion theorems for maps to Banach lattices

We investigate semi-continuous maps from topological spaces into topological vector lattices. As an application, several insertion theorems with values in Banach lattices are given.