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The most parts of thesis as follows:1. Five symmetrical intra-molecular charge transfer oligomeric phenylene vinylene light emitting materials were designed and synthesized using oligomeric phenylene vinylene as a framework.2. The structures of target molecule were characterized by ~1HNMR,~(13)CNMR, IR, MS and element analysis.3. In order to study the influence of the location and numbers of electron-donor and electron-acceptor on their photoelectric performance by changing length of OPV chain, the UV spectra and fluorescence spectra of target compounds has been compared. We have researched into main factors effecting on material emitting red-shift; organic electroluminescence device was prepared using the compound P4. The capability of eletroluminescence was researched.4. The photoelectric properties of P4 was explained by quantum chemical calculation (the Gaussian 98 quantum chemistry program). It is greatly contributed know the whole process of charge transfer to guide the design of red emitters.

本文研究的内容主要包括以下部分：(1)设计并合成5个对称的以齐聚苯乙烯类为骨架的分子内电荷转移型齐聚苯乙烯类发光材料；(2)通过IR，MS，~1H-NMR，~(13)C-NMR和元素分析对所合成的目标化合物进行表征；(3)通过对目标化合物的紫外光谱和荧光光谱比较分析，研究改变OPV的长度，电子给体和电子受体的位置及数量对其光电性能的影响，探讨材料发射红移的主要因素；选取性能良好的目标化合物P4制备成OELD器件，对其电致发光性能进行研究；(4)运用Gaussian98量子化学程序包，采用量子化学方法对目标化合物P4的光电性能从理论加以解释，进一步认识荷移跃迁的整个过程，为红光材料的设计加以指导。

A series of novel dicationic symmetrical and asymmetrical ionic liquids based on tributylalkyl phosphonium and alkylimidazolium were synthesized.

合成了一系列含有三丁基烷基膦盐和烷基咪唑盐的对称的和不对称的双离子液体。

It was shown that the 3D deformation in the tunnel at soft rock was obvious at F7 fault and phyllite section, with the characteristics of large deformation and longitudinal displacement developing in the opposite direction of work face and being stable at a distance about 2.0 times of tunnel diameter from the work face. And the 3D displacement of tunnels at F7 fault zone developed in an uneven symmetrical way, while there was good consistency for 3D deformation at slate section. Furthermore, there was a mutally verifying relationship between 3D deformation and ground stress distribution of tunnel region.

结果表明，F7断层和千枚岩地段软岩隧道三维位移十分明显，具有隧道大变形特性，其纵向位移背离开挖面方向发展并在相距开挖面约2.0倍洞径时趋于稳定状态；F7断层地段隧道三维位移呈不均匀对称地发展变化，而板岩地段三维位移变化的一致性较好；隧道三维变形规律与隧道区域地应力场的分布存在相互印证关系。

Any of various parasitic and non parasitic worms of the phylum Platyhelminthes,such as a tapeworm or a planarian,characteristically having a soft,flat,bilaterally symmetrical body and no body cavity.

扁虫扁形动物门的寄生或非寄生虫中的任一种，以具有柔软、扁平且两面对称的身体和无体腔为特征，如绦虫或涡虫

Any of various parasitic and nonparasitic worms of the phylum Platyhelminthes, such as a tapeworm or a planarian, characteristically having a soft, flat, bilaterally symmetrical body and no body cavity.

扁虫扁形动物门的寄生或非寄生虫中的任一种，以具有柔软、扁平且两面对称的身体和无体腔为特征，如绦虫或涡虫

Radially symmetrical, so that a line drawn through the middle of the structure along any plane will produce a mirror image on either side.

辐射对称 Actinomorphous 辐射状对称，通过结构中央的任一平面都能将其分成互为镜像的两部分。

Bilaterally symmetrical, so that a line drawn through the middle of the structure along only one plane will produce a mirror image on either side.

左右对称的 Zygomorphous 两侧对称，仅在，通过结构中央仅有一个平面能将其分成互为镜像的两部分。

A half of a symmetrical, approximately spherical object as divided by a plane of symmetry.

半球体：一个对称的、近似球体的物体的一半，如被对称面分开者

Our machine adopts level principle. The symmetrical roller assembly is connected by horizontally placed spring rod. When the large material touches the roller assembly, to keep balance, the radial force may pass to the roller assembly which is plane of symmetry through spring rod. Under this condition, the whole device's bearing is improved about 40% than that of others; the forming resilient connection can reduce the vibration and noise, and avoid resonance.

该机采用杠杆原理，将对称的磨辊总成用水平放置的弹簧通过拉杆连接在一起，当大块物料顶摆一个磨辊总成时，其径向力可通过弹簧拉杆传给对称面的磨辊总成来平衡，此条件下，装置的整体受力点和其它产品相比提高了40%左右；而弹性联结装置则减轻了振动和噪音，避免了共振。

Using two symmetrical plano-convex lens system to fabricate grating was analyzed and the characteristic of diffraction wavefront aberration of the grating was summarized by ray tracing program using MATLAB siftware.

分析使用两个对称的单平凸透镜光路制作光栅并用MATLAB编写光线追迹程序分析了所制作的光栅的衍射波像差的特点，经计算得出在较小焦比D/F情况下其衍射波像差仅与两支光路点光源的调节偏差之差有关与单独的各个偏差无关；初级像差中球差很小几乎可忽略：彗差仅与垂轴调节偏差之差成线性关系；像散仅与轴向调节偏差之差成正比；且当平凸透镜的焦比D/F增大时，各像差项迅速增大。

As she looked at Warrington's manly face, and dark, melancholy eyes, she had settled in her mind that he must have been the victim of an unhappy attachment.

每逢看到沃林顿那刚毅的脸，那乌黑、忧郁的眼睛，她便会相信，他一定作过不幸的爱情的受害者。

Maybe they'll disappear into a pothole.

也许他们将在壶穴里消失