Pole placement controllers for linear time-delay systems with commensurate point delays

This paper investigates the exact and approximate spectrum assignment properties associated with realizable output-feedback pole-placement type controllers for single-input single-output linear time-invariant time-delay systems with commensurate point delays. The controller synthesis problem is discussed through the solvability of a set of coupled diophantine equations of polynomials. An extra complexity is incorporated to the above design to cancel extra unsuitable dynamics being generated when solving the above diophantine equations. Thus, the complete controller tracks any arbitrary prefixed (either finite or delaydependent) closed-loop spectrum. However, if the controller is simplified by deleting the above mentioned extra complexity, then the robust stability and approximated spectrum assignment are still achievable for a certain sufficiently small amount of delayed dynamics. Finally, the approximate spectrum assignment and robust stability problems are revisited under plant disturbances if the nominal controller is maintained. In the current approach, the finite spectrum assignment is only considered as a particular case to the designer‘s choice of a (delay-dependent) arbitrary spectrum assignment objective.     

INVESTIGATION OF STRUCTURE AND PROPERTIES FOR POLYMER SYSTEMS BASED ON DYNAMIC RHEOLOGICAL APPROACHES

The dynamic theological measurements have been a preferred approach to the characterization of the structure and properties for multi-component or multi-phase polymer systems, due to its sensitive response to changes of structure for these heterogeneous polymers. In the present article, recent progresses in the studies on dynamic theology for heterogeneous polymer systems including polymeric composites filled with inorganic particles, thermo-oxidized polyolefins, phaseseparated polymeric blends and functional polymers with the scaling and percolation behavior are reviewed, mainly depending on the results by the authors‘ group. By means of theological measurements, not only some new fingerprints responsible for the evolution of morphology and structure concerning these polymer systems are obtained, the corresponding results are also significant for the design and preparation of novel polymer-based composites and functional materials.     

Mo-Co系加氢精制催化剂中TiO~2-Al~2O~3载体效应的PASCA研究

本文采用PASCA(化学分析正电子湮没谱)技术, 系统地研究了MoO~3/γ-Al~2O~3,CoO/γ-Al~2O~3, MoO~3/TiO~2-Al~2O~3, CoO/TiO~2-Al~2O~3等体系中活性组分的表面分散状态和化学状态及其变化规律, 揭示了用TiO~2改性Al~2O~3对Mo-Co系加氢精制催化剂所产生的载体效应的作用机理。Al~2O~3中引入TiO~2使得载体与MoO~3间的相互作用大大减弱, 导致分散态MoO~3易于还原和硫化。助剂CoO与TiO~2-Al~2O~3载体间存在极为显著的电子相互作用, 对于改善Co在活性相中的化学状态, 提高活性中心的内在活性具有重要的作用。PASCA研究的另一个重要结果是, 由于载体表面的不均匀性,使得上述负载型催化剂中氧化物活性组分的表面状态十分复杂, 存在与载体相互作用强弱程度不同的多类特征区, 这些特征区与内在活性不同的催化中心相关联. 通过TiO~2改性Al~2O~3载体, 有效地调节载体表面性质, 改变活性组分表面物种的分布及化学状态。     

A Note on Light Velocity Anisotropy

It is proved that in experiments on or near theEarth, no anisotropy in the one-way velocity of lightmay be detected. The very accurate experiments whichhave been performed to detect such an effect are to be considered significant tests of bothspecial relativity and the equivalenceprinciple.     

不同取代三氟苯乙烯交叉环加成反应过渡态的额外极性相互作用 1. 对三氟甲基苯乙烯和对甲氧基三氟苯乙烯环加成反应的动力学研究

利用KINETICS-1计算机程序, 测定了在120-160℃四个温度下对甲氧基三氟苯乙烯与对三氟甲基三氟苯乙烯的交叉和均环加成反应的速率常数. 我们的数据, 特别是与交叉环加成反应的趋向有关的, 并由方程(10)所定义的φ函数值(1.4-1.9)表明, 在电子基取代的和吸电子基取代的三氟苯乙烯之间的交叉环加成反应的过渡态中, 非常可能存在着一个额外的极性相互作用.     

Comment on the Roberts Solution for the Spherically-Symmetric Einstein-Scalar Field Equations

We critically examine the Roberts homothetic solution for the spherically symmetric Einstein-scalar field equations in double null coordinates, and show that the Roberts solution indeed solves the field equations only for one non-trivial case. We generalize this solution and discuss its relations with other known exact solutions.     

计算机辅助的羧肽酶法测定多肽羧端顺序

在初步用计算机辅助的羧肽酶法测定了天花粉蛋白C-端顺序的基础上, 进一步设计了两个计算机程序-DPS程序和CPA程序. 用合成小肽和天然的肽对这两个计算机程序进行模型实验证明, 运用这两个程序能分别满意地从羧肽酶的酶解动力学曲线中获得重要的C-端顺序信息, 并测定了天花粉蛋白分子中未知肽段CB-3的C-端顺序为: -SerAlaSerAlaLeuHserOH, 这一顺序后来已经其他实验结果所证实. 本法不仅使C-端顺序测定延长至七个氨基酸, 而且还基本上解决了多肽或蛋白质含有多种多次重复氨基酸残基的C-端顺序测定.     

A Lemma On C 0 -semigroups And Applications

In this note we characterize a large class of C ₀-semigroups which can be applied to prove the existence and the uniqueness of the solutions of many systems of partial differential equations. In fact, we apply our result to a strongly damped wave equation, damped vibration of a string equation and reaction diffusion systems. Finally, we formulate an open problem.     

NEW INITIATION SYSTEMS FOR ATOM TRANSFER RADICAL POLYMERIZATION

This review summarizes our achievements in designing new initiation systems for atom transfer radical polymerization (ATRP). First-order kinetics and extension experiments revealed the living nature of these reactions. Tailormade vinyl polymers with functional end groups were characterized by ^1H-NMR and UV-vis spectroscopic analyses. Replacing traditional radical initiators AIBN and BPO, carbon-carbon bond compounds, 1,1,2,2-tetraphenyl-l,2-ethanediol, diethyl 2,3-dicyano-2,3-diphenylsuccinate and diethyl 2,3-dicyano-2,3-di(p-tolyl)succinate, were utilized in reverse ATRP to produce the initiating radical. Sulfur-sulfur bond iniferter, tetraethylthiuram disulfide (TD), in conjunction with CuBr/bpy or NiCI2/PPh3 complex could control the styrene polymerization via redox reaction. Pseudo-halogen transfer reaction was demonstrated to maintain the dormant-active species equilibrium in normal and reverse ATRP with Cu(S2CNEt2), Cu(S2CNEt2)CI and Fe(S2CNEt2)3 as catalysts. The organic halide initiator and reduced transition metal compound that started the living polymerization were produced in situ from the components of TD/FeCI3/PPh3, TD/CuBr2/bpy and Fe(S2CNEt2)3/FeCI3/PPh3 systems. Accurate control of UV irradiation time favored the radical generation process in photo ATRP with the 2,2-dimethoxy-2-phenylacetophenone/Fe(S2CNEt2)3 initiation system.     

Na2O-SiO2-Al2O3-NaCl-H2O体系中ANA和SOD沸石膜的水热合成

Na2O-SiO2-Al2O3-NaCl-H2O体系中，以水玻璃和准一水软铝石为原料，分别在 堇青石和玻璃载体上水热合成方沸石（ANA）和方钠石（SOD）沸石膜。研究水含量 、反应温度、反应时间与多次合成对膜结晶的影响。用XRD，SEM，EDX表征膜的晶 相、形貌和化学组成。堇青石负载方沸石膜在对95％（wt.)乙醇水溶液的渗透蒸发 实验中，水优先透过沸石膜的选择性显示了晶间孔的醇／水分离作用。非计量的 NaCl进入到在玻璃载体上成膜的方钠石笼中，致使该膜显示光致变色效应。