Construction of different supramolecular polymer systems by combining the host–guest and hydrogen‐bonding interactions

Poly(ethylene glycol) (PEG) can form either the inclusion complex with α‐cyclodextrins (α‐CDs) through host–guest interactions or the interpolymer complex with poly(acrylic acid) (PAA) through hydrogen‐bonding interaction. Mixing α‐CD, PEG, and PAA ternary components in an aqueous solution, the competition between host–guest and hydrogen‐bonding interactions occurs. Increasing feed ratio of α‐CD:EG:AA from 0:1:1 to 0.2:1:1 (molar ratio), various interesting supramolecular polymer systems, such as hydrogen‐bonding complex, dynamic polyrotaxane, crystalline inclusion complex, and thermoresponsive hydrogel, are successively obtained. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 1114–1120, 2008     

Synthesis of a New Type of Amphilic and Water—soluble Tertiary Phosphine Ligands Substituted by an Ethoxylated Phosphonic Acid Chain and Their Palladium Complexes

The highly water-soluble phosphine ligands Na2O3PCH2CH2NH(CH2CH2O)nCH2CH2N-(CH2PPh)22(n=1,2,3) were prepared by a new and simple route under mild conditions in good yield; the palladium (Ⅱ） complexes of the ligands 3a-c with 2:1 or 4:1 -PPh2 to Pd^2 molar ratio were also prepared and characterized.     

长焦距光学系统杂光系数测试仪

报告了一种新的长焦距光学系统杂光系数测量装置,该装置除具有避免了制作大直径积分球的优点外,还能精确测量轴外杂光系数,分析各部分杂光源对杂光系数的影响.     

空间两维指向摆镜的成象分析

本文分析了航天摄影相机的指向摆镜统二轴摆动时的成家关系,讨论了摆镜引起的象倾斜及象倾斜角与摆镜摆角的关系,并论述了象倾斜的校正方法;本文还讨论了摆镜对地面的扫描轨迹和覆盖范围.     

大平面二极管虚阴极振荡器的宽脉冲微波辐射

给出了产生宽脉冲微波辐射的大平面天鹅绒二极管虚阴极振荡器的结构和测试装置，测得了二极管中阴－阳极等离子体的闭合速率为３０～４３ｋｍ／ｓ，获得了微波辐射的最大脉宽为１．５μｓ，产生的微波峰值功率约为１５ＭＷ，频率为０．５ＧＨＺ，指出这种平面二极管型虚阴极振荡器在辐射脉宽，辐射频率和辐射功率三者之间存在着物理上的制约关系，认为同轴型虚阴极振荡器是突破这种制约关系的一个新途径．     

Synthesis of Highly Branched Poly（ε-caprolactone） by Self-condensing Atom Transfer Radical Polymerization of Macroinimers

Fréchet et al.1 in 1995 prepared hyperbranched vinyl polymers by the technique named self-condensing vinyl polymerization (SCVP) of initiator-monomers (“inimers”) having the general structure AB*, where A stands for a double bond and B* for an initiati…     

高分子梯度溶液吸声机理的研究

制备了高分子均匀溶液和梯度溶液,并在声管中测试其声衰减性能.实验结果表明,高分子梯度溶液的声衰减效果明显优于(即大于)相应的均匀溶液的声衰减.根据连续分层介质中声波传播理论建立了计算高分子梯度溶液声衰减的数学模型.计算结果与实验结果一致.由实验和理论分析结果得出了高分子梯度溶液的梯度吸声机理,即多次反射、多次吸收,最终将声能转化为热能.     

带隙法测定SiGe/Si材料的应变状态

从固体模型理论的结果出发，计算了生长于Si（100）衬底上x值小于085的Si_1-xGe_x合金材料（能带结构为类Si结构）的间接带隙与应变的关系，结 果表明，应变的S iGe材料的带隙和完全弛豫状态下材料的带隙之差与应变呈线性关系.基于这一结果，提出了 用测量带隙来间接测定SiGe/Si应变状态的方法.用带隙法和x射线双晶衍射法测量了不同应 变状态下的SiGe/Si多量子阱材料的应变弛豫度，两者可以较好的符合，表明带隙法测量SiG e应变弛豫度是可行的. 关键词： SiGe合金 应变 带隙     

1.5MeV LIA脉冲功率系统

本文简要介绍了1.5MeV LIA脉冲功率系统的结构、组成和设计思想;给出了开关运行参数和确定开关时间抖动指标的方法、闭环系统的总抖动对加速电压相对变化的影响、脉冲功率系统各段输出波形和电压幅度的调制关系;测量结果表明,1.5MeV LIA的运行功率和时间同步满足总体设计要求。