On parakähler Hom-Lie algebras and Hom-left-symmetric bialgebras

In this paper, the parakähler Hom-Lie algebras or phase space of Hom-Lie algebras in terms of Hom-left-symmetric algebras are studied. A structure theory of parakähler Hom-Lie algebras in terms of matched pairs of Hom-Lie algebras is also presented. Besides, the bimodules of Hom-left-symmetric algebras are investigated. Furthermore, Hom-left-symmetric bialgebra which is precisely equivalent to parakähler Hom-Lie algebra is introduced. Especially, the coboundary Hom-left-symmetric bialgebra is considered.     

UV irradiation gradient induced banded texture in photo-polymerized ethyl-cyanoethyl cellulose/poly(acrylic acid) cholesteric liquid crystalline films and patterns fabrication thereof

The photo-polymerization-induced banded texture of ethyl-cyanoethyl cellulose/acrylic acid/copper acrylate ((E-CE)C/AA/CuAA₂) cholesteric liquid crystalline (CLC) solutions were investigated. The results indicate that the CLC phase can be fixed by the photo-polymerization. Banded texture was obtained in the photo-polymerized CLC films. The orientation of the banded texture induced by the photo-polymerization depends on the gradient of UV irradiations on the surface of the (E-CE)C/AA/CuAA₂ CLC solutions. CLC films with different patterns can be obtained by introducing the UV irradiation gradient on the (E-CE)C/AA/CuAA₂ CLC solutions surface by using masks with different patterns. The simple approach for the fabrication of CLC films with different patterns may have the potential application in the fields of holographic image storage.     

Graphs determined by their generalized characteristic polynomials

For a given graph G with (0, 1)-adjacency matrix A_G, the generalized characteristic polynomial of G is defined to be ?_G=?_G(λ,t)=det(λI-(A_G-tD_G)), where I is the identity matrix and D_G is the diagonal degree matrix of G. In this paper, we are mainly concerned with the problem of characterizing a given graph G by its generalized characteristic polynomial ?_G. We show that graphs with the same generalized characteristic polynomials have the same degree sequence, based on which, a unified approach is proposed to show that some families of graphs are characterized by ?_G. We also provide a method for constructing graphs with the same generalized characteristic polynomial, by using GM-switching.     

三元混配铂(Ⅱ)配合物的稳定性和分子内芳环堆积效应研究

用 pH电位滴定法测定了铂 (Ⅱ )与核苷酸NTP (NTP为腺苷 5′ 三磷酸和尿苷 5′ 三磷酸 )和另一芳环系列配体ArL形成的三元混配配合物Pt(ArL) (NTP) n -(ArL =Phen ,Bpy和Trp ;n =2或 3)在水溶液中的稳定常数 (I=0 .1mol/L ,KNO3 ;2 5℃ ) .用ΔlogKPt比较了二元和三元混配配合物的稳定性差异 ,认为三元混配配合物稳定性的增加可归因于π 酸与π 碱之间的合作效应和分子内芳环配体的堆积作用     

Design and analysis of two-dimensional photonic crystals channel filter

A novel three-port channel add/drop filter consisting of two waveguides and two cavities is proposed. One is used for a resonant tunneling-based channel add/drop operation from the bus waveguide to the add/drop waveguide, while the other is used to realize the wavelength-selective reflection feedback in the bus waveguide. By means of coupled mode theory in time, the conditions to achieve 100% add efficiency are derived thoroughly. Based on these theoretical analysis, the channel add filter and some other multi-channel filters are designed in two-dimensional photonic crystals (2D PCs) with square lattice of dielectric rods in air. The numerical results by using the finite-difference time-domain (FDTD) method demonstrate almost complete channel add/drop tunneling at resonance via the three-port systems.     

提高超声测距分辨力的分析与设计

本文分析了分辨力误差的定量关系，并以此为指导选择和设计超声发射，接收，测时等电路以及数字滤波方法，提亢超声测距的精度和分辩力。     

非自治Lotka-Volterra扩散模型的持续生存与周期轨道(英)

本文研究了一类非自治的捕食者一食饵扩散模型；其中食饵能在环境相异的两个缀块间有限制地扩散，但对捕食者来说，缀块间的扩散不受任何限制；另外假设模型的系数都是时间的函数．我们证明了在适当的条件下，这个系统能够持续生存，进一步给出了系统存在唯一全局渐近稳定正周期轨道的充分条件．     

高阶非线性微分方程的全局稳定性

本文通过将高阶非线性自治微分方程转化为Ｌｕｒｉｅ型控制系统的方法，借助于Ｐｏｐｏｖ的频率判据，得到了它们全局渐近稳定的判别准则，推广了文［１］的结果．     

Two novel non-viral gene delivery vectors: low molecular weight polyethylenimine cross-linked by (2-hydroxypropyl)-beta-cyclodextrin or (2-hydroxypropyl)-gamma-cyclodextrin

Two novel polymers of low molecular weight polyethylenimine cross-linked by (2-hydroxypropyl)-beta-cyclodextrin or (2-hydroxypropyl)-gamma-cyclodextrin showed lower cytotoxicity and higher transfection efficiency for the delivery of plasmid DNA compared with those of polyethylenimine (PEI, 25 kDa).