Studies on the electron transfer centers of amino oxidase immobilized on self-assembly monolayer using electrochemical methods

The direct electron transfer of amino oxidase on electrode surface based on self-assembly technique occurs at 505 mW(vs. Ag/AgCl), indicating that copper atoms are the electron transfer centers and catalytic centers of amino oxidase.

NMR study of doped poly(2,5-dimethylaniline)

Structure changes and charge transfer in the doping process of poly(2,5-dimethylaniline) (PDMA) were studied by NMR technique. It was shown that not only the polymer chain but also the hydrogen atoms and methyl groups on the aromatic rings were involved in the charge transfer process. A ''four ring BQ derivatives'' model was proposed to explain the NMR results.

Al-Li-Ymm合金的组织和腐蚀性能

对Al-3.1Li及Al-2.7Li-0.21Ymm二种合金的铸态及在540℃条件下固溶处理４小时后的组织进行了观察和分析，测定了二种合金在3.5%NaCl水溶液中的电化学腐蚀性能。结果表明：二种合金的宏观组织未见明显示差别，含Ymm的合金微观组织较细化，添加少量Ymm对合金的腐蚀性能有较好的影响，固熔处理后的合金耐腐性能提高

Synthesis of lanthanide-alkylaluminium bimetallic complexes and studies on their catalytic activities for polymerization of some polar monomers

Three new lanthanide (Ln)-alkylaluminium (Al) bimetallic complexes with the formula [(mu-CF3CO2)(2)Ln(mu-CF3CHO2)AIR(2) . 2THF](2) (Ln = Nd, Y, R=i-C4H9 (i-Bu); Ln=Eu, R=C2H5(Et); THF=tetrahydrofuran) were synthesized by the reaction of Ln(CF,CO,), (Ln=Nd, Y) with HAI (i-Bu)(2) and of Eu(CF3CO2)(3) with AlEt(3), respectively. Their crystal structures were determined by X-ray diffraction at 233 K. [(mu-CF3CO2)(2)Nd (mu-CF3CHO2)Al(i-Bu)(2) . 2THF](2) (Nd-Al) and [(mu-CF3CO2)(2)Y(mu-CF3CHO2)Al(i-Bu)(2) . 2THF](2) (Y-Al) are isomorphous and crystallize in space group with a=12.441(3) Angstrom [12.347(5) Angstrom for Y-Al], b=12.832(3) Angstrom [12.832(4) Angstrom], c=11.334(3) Angstrom [11.292(8) Angstrom], alpha=104.93 (2)degrees [104.45(4)degrees], beta=98.47(2)degrees [98.81(4)degrees], gamma=64.60(2)degrees [64.30(3)degrees], R=0.519 [0.113], R(w)=0.0532 [0.110], Z=1 and [(mu-CF3CO2)(2)Eu(CF3CHO2)AlEt(2) . 2THF](2)(Eu-Al) in space group P2(1)/n with a=11.913(6) Angstrom, b=14.051(9) Angstrom, c=17.920(9) Angstrom, alpha=101.88(11)degrees, beta=gamma=90 degrees, R=0.0509, R(w)=0.0471 and Z=2. The six CF3CO2- (including CF3CHO2-) of each complex, among which pairs are equivalent, coordinated to Ln and Al in three patterns: (A) the two oxygen atoms in one of the three CF3CO2- type coordinated to two different Ln; (B) the two oxygen atoms in the second of CF3CO2- type coordinated to Ln and Al, respectively; (C) one of the two oxygen atoms in the third CF3CO2- type bidentately coordinated to two Ln and another oxygen coordinated to Al and one of the two Ln, respectively. Unlike types A and B, in type C the carboxyl carbon with a hydrogen atom bonded to it was found to appear as an sp(3)-hybridized configuration rather than an sp(2)-one. 1D and 2D NMR results further confirmed the existence of such a disproportionated CF3CHO2- ligand. Methyl methacrylate (MMA) and epichlorohydrin (ECH) could be polymerized by Y-Al or Eu-Al as a single-component catalyst and highly syndiotactic poly(MMA) was obtained. THF could also be polymerized by Y-Al in the presence of a small amount of ECH.

Synthesis and thermal transitional properties of side-chain liquid crystalline polyacrylates containing para-nitroazobenzene as mesogenic groups

The synthesis and characterization of side-chain liquid crystalline (LC) polyacrylates containing para-nitroazobenzene (Pn) as mesogenic groups were described. Homopolymers with 3 and 4 carbon atoms in the spacers were non-LC polymers; for homopolymers with 6 carbon atoms in the spacer, nematic LC behavior was observed. Copolymers with acrylic acid as one component exhibited an S-Ad phase according to the WAXD results which showed the d/l of 1.4-1.54 for the copolymers with 3, 4, and 6 carbon atoms in the spacers. Considering the molecular structure as well as the WAXD results of the copolymers, the possible molecular arrangement in the smectic Sad phase was proposed, in which the smectic layers were composed of the antiparallel mesogens and the antiparallel arrangement was considered to be enhanced due to the H bond between - COOH and - NO2. The stress-induced orientational phenomena of Pn in the LC states was also discussed. (C) 1996 John Wiley & Sons, Inc.

The phase transitions of hetero atoms substituted molecular sieves Me-VPI-5(Me=Mg, Ti, Sn, Si) and their influence on spectra structures of Eu(III) ion

The hetero atom substituted aluminophosphate molecular sieves Me-VPI-5(Me = Mgt Ti, Sn, Si) were synthesized hydrothermally. Rare earth ions are originally doped into these microporous materials by aqueous solution ion exchange procedures. The phase transitions of the microporous materials are investigated by high-temperature and high-pressure experimental techniques. The influence of the phase transitions on the rare earth ions' spectral structures is discussed, With the increase of temperature, Eu(II)Mg-VPI-5 is converted into Eu(II)Mg-AIPO(4)-8, then into tridymite phase. The pressure has a notable influence on Eu(II) ion's spectral structures. The spectral structures have changed regularly with the increase of pressure.

A new zirconocene complex, [{eta(5)-C5H4-C(CH2)(5)(CH2)(2)CH(CH3)(2)}2ZrCl2]

The title compound, dichlorobis{eta(5)-[1-(3-methylbutyl)-cyclohex-1 -yl]cyclopentadienyl}zirconium(IV), [ZrCl2-(C16H25)(2)], has a pseudo-tetrahedral bent-metallocene structure in which the substituted cyclopentadienyl rings are asymmetrically bonded to the central Zr atom, due primarily to the interaction between the large substituents and the Cl atoms. The molecule has local C-2 symmetry with the substituents positioned in a trans arrangement and directed towards the lateral sectors of the bent-metallocene unit.

Preparation and characterization of polymer-supported rare earth complexes

The polymers containing different ligand groups of atoms (mainly O, N, and S) and their rare earth complexes were prepared, characterized and classified based on the type of metal-ligand tending. The catalytic activities of the complexes are briefly discussed. The polymer-supported rare earth complexes showed much greater activities than the corresponding complexes with a low molecular weight.

IONIC-CONDUCTION OF A NOVEL COMB POLYMER ELECTROLYTE BASED ON MALEIC-ANHYDRIDE COPOLYMER WITH OLIGO-OXYETHYLENE SIDE-CHAINS

A comb-shaped polymer (BM350) with oligo-oxyethylene side chains of the type -O(CH2CH2O)(7)CH3 was prepared from methyl vinyl ether/maleic anhydride copolymer. Homogeneous amorphous polymer electrolyte complexes were made from the comb polymer and LICF(3)SO(3) by solvent casting from acetone, and their conductivities were measured as a function of temperature and salt concentration. Maximum conductivity close to 5.08 X 10(-5) Scm(-1) was obtained at room temperature and at a [Li]/[EO] ratio of about 0.12. The conductivity which displayed non-Arrhenius behaviour was analyzed using the Vogel-Tammann-Fulcher equation and interpreted on the basis of the configurational entropy model. The results of mid-IR showed that the coordination of Li+ to side chains made the C-O-C band become broader and shift slightly. X-ray photoelectron spectroscopy analysis indicated that the oxygen atoms in the two situations could coordinate to Li+ and this coordination resulted in the reduction of the electron orbit binding energy of F and S.

SYNTHESIS AND CHARACTERIZATION OF POLYACRYLATES CONTAINING CHARGE-TRANSFER GROUPS

Polyacrylates containing para-nitro azobenzene have been synthesized by free radical polymerization. The influence of the length of the spacer of the homopolyacrylates (HPn, n=3,4,6), content of methyl acrylate in the copolyacrylates (CP6) with para-nitro azobenzene groups on the thermal properties, such as liquid crystallinity, Tg and Tm, was studied by DSC, WAXD and polarized optical microscopy. Among the polymers studied, only the homopolyacrylate (HP6)with six carbon atoms in the spacer exhibited a nematic phase. The second-harmonic generation (SHG) signal of the poled HP6 film was detected qualitatively by Maker-fringer method.

Crystal and molecular structure of the complex of methoxycarbonylethyltin trichloride with salicylidene-m-toluidine

The synthesis and properties of the title complex CH3OCOCH2CH2SnCl3.2-HOC6H4CH=NC6H4-3'-CH3 are described. It crystallizes from benzene in the monoclinic space group P2(1/n) with unit cell dimensions a=10.326 (C),b=6.815(8), c=12.931(6) Angstrom, beta =111.52(3,)degrees, V=2088.7(1) Angstrom (3), Z=4, F(000) =1040, mu =16.31 cm(-1), Dc=1. 67g/cm(3) final R factor is 0.037 for 3177 observed reflections, 1 greater than or equal to3 sigma (1(0)). The tin atom in the structure of the complex exists in a distored octahedral geometry defined by three Cl atoms, the C and O atoms of a chelating methoxycarbonylethyl. group as well as an O atom derived from the Schiff base ligand.

甲烷氧化偶联Ti-La-Li系多元氧化物催化剂的表面碱性和表面活性氧种

利用CO2-TPD方法考察了Ti-La-Li系多元氧化物催化剂的表面碱性,实验发现:C2 选择性与表面碱强度呈顺变关系,而CH4 转化率与CO2 的脱附峰面积呈顺变关系.同时,利用XPS,O2-TPD等方法对该体系催化剂的表面活性氧种进行了表征与研究,结果表明:催化剂的表面晶格氧与C2 选择性有关,表面吸附氧与甲烷转化(包括偶联和深度氧化)有关.O2 -TPD实验发现催化剂的表面存在三种氧:α( 100℃≤t≤450℃),β(450℃

TRIS(TERT-BUTYLCYCLOPENTADIENYL)NEODYMIUM-MU-CHLORO-TRIS(TETRAHYDROFURAN)LITHIUM, [ND(ETA(5)-(T)BUCP)3(MU-CL)LI(THF)3]

The title complex, tris[2(eta5)-tert-butylcyclopentadi-enyl]-mu-chloro-1:2kappa2Cl-tris(tetrahydrofuran-1kappaO)lithiumneodymium, [Nd(C9H13)3(mu-Cl)Li(C4H8O)3], consists of the neutral moiety ((t)BuCp)3Nd linked to the cation [Li(thf)3]+ by a mu-Cl bridge

SYNTHESIS AND CRYSTAL-STRUCTURE OF [LI(THF)4][((T)BUCP)YB(NPH2)3]

The title complex [Li(THF)4] [(tBuCp)Yb(NPh2)3] was synthesized by the reaction of t-butylcyclopentadienyl ytterbium dichloride with 2 equivalents of LiNPh2 in THF, hexane, and toluene at -78-degrees-C. The complex was characterized by elemental analysis,

Study of Methane Oxidative Coupling over Ti-La-Li Mixed Oxides

The composition and structures of Li-Ti-La mixed oxides as well as their catalytic activity for methane oxidative coupling have been studied by means of XRD XPS, IR, SEM and so on. The results indicate that by changing x value in Li-La1-xTixO2 oxides phas