VOLT-AMPERE CHARACTERISTICS OF CIS-POLY(PHENYL ACETYLENE)

The volt-ampere (Ⅰ-Ⅴ) characteristics of the c/s-poly (phenyl acetylene) (PPA) of cis-transoidal structure has been studied in the temperature range of 253-288K. An ITO/ PPA/ Au sandwich configuration was used for the measurements. Under an applied field of less than 10~5V/ cm it showed ohmic behavior, while the space charge limited current (SCLC) was observed at applied fields above 5×10~5V/ cm. In the ohmic region a conductivity of 1.37×10^(-16)S/ cm was obtained at room temperature with an activation energy of 0.5eV. These data indicate that the conduction is not intrinsic one but is the result of thermal release of trapped carriers. In fact the data in the SCLC region treated according to the theory for a single Gaussian distribution of traps gave a mean trap energy of 0.48 eV with a half-width of 0.4 eV and a total density of trapping states of 5×10^(16)/cm^3.

Crystal Structure and Spectroscopic Analysis of Polyphenyl Quinoxaline with Hg(Ⅱ)

The interaction of Hg^2＋ with polyphenyl quinoxaline ligand 2,3,6,7,10,11-hexaphenyldipyrazino[2,3-f：2＇,3＇-h]quinoxaline（HPQ） was investigated, and a new complex（C（49）H（32）N6Br2Cl2Hg） has been synthesized and characterized. It exhibits a 0D single-core structure,and adopts triclinic P 1 space group with a = 11.139（2）, b = 13.429（3）, c = 14.488（3）A, α =76.10（3）, β = 83.16（3）, γ = 87.36（3）o, V = 2088.4（7） A^3, Z = 2, S = 1.056, F（000） = 1104, R = 0.0417 and w R = 0.0931（I 〉 2σ（I））. Furthermore, the behavior of HPQ with Hg^2＋ in the solution was also investigated, and the result shows that HPQ was found to have excellent fluorescent selectivity for Hg^2＋ over many other metal ions（Li^＋, K^＋, Na^＋, Sr^＋, Ca^2＋, Mg^2＋, Mn^2＋, Fe^3＋, Ni^2＋, Co^2＋, Cu^2＋, Zn^2＋,Cd^2＋, Pb^2＋, Al^3＋ and Cr^3＋） based on the intermolecular charge-transfer mechanism, which makes HPQ a potential fluorescence sensor or probe for Hg^2＋.

Hydrolysis of Polyphenyl-1,2,4-triazine and Polyphenyl-1,3,5-triazine in High Temperature Water

The hydrolysis of polyphenyl 1,2,4 triazine (As PPT) and polyphenyl 1,3,5 triazine (S PPT) in water at 250℃/ 3.97 MPa under nitrogen atmosphere has been investigated experimentally and theoretically. The hydrolysis reactions were monitored by Fourier transform infrared (FT IR) and ultra violet visible (UV Vis) spectra. The results show that S PPT is remarkably stable whereas As PPT is easily hydrolyzed in water at 250℃. The identifications using FT IR, high performance liquid chromatography (HPLC), nuclear magnetic resonance ( 1H NMR) and mass spectrography (MS) confirm that terephthalic acid is the major hydrolysate of As PPT. Two model compounds, 2,5,6 triphenyltriazine and 2,4,6 triphenyltriazine, were designed to simulate the local electronic structures of As PPT and S PPT, respectively. The electronic structures were given by ab initio calculations at the RHF/4 31G level. The calculational results indicate that the triazine rings are the hydrolytically active parts and the 1,2,4 triazine ring is easier to hydrolyze in comparison with the 1,3,5 triazine ring under the same condition.

Hosoya and Merrifield-Simmons Indices in Random Polyphenyl Chains

The Hosoya index of a graph is the total number of matchings in it. And the Merrifield-Simmons index is the total number of independent sets in it. They are typical examples of graph invariants used in mathematical chemistry for quantifying relevant details of molecular structure. In this paper, we obtain explicit analytical expressions for the expectations of the Hosoya index and the Merrifield-Simmons index of a random polyphenyl chain.

Hosoya and Merrifield-Simmons Indices in Random Polyphenyl Chains

The Hosoya index of a graph is the total number of matchings in it.And the Merrifield-Simmons index is the total number of independent sets in it.They are typical examples of graph invariants used in mathematical chemistry for quantifying relevant details of molecular structure.In this paper,we obtain explicit analytical expressions for the expectations of the Hosoya index and the Merrifield-Simmons index of a random polyphenyl chain.

THREE KIRCHHOFFIAN INDICES OF THE CACTUS GRAPHS

In this paper we give six explicit formulae to compute the Kirchhoff index,the multiplicative degree-Kirchhoff index and the additive degree-Kirchhoff index of the k-cactus chain and the cactus graph which can be obtained from a k-cactus chain by expanding each of the cut-vertices to a cut edge.