Effect of carbon nanotubes, as a novel support material, on the performance of Rh-catalyst supported by them was studied. Catalysts based on carbon nanotubes, SiO2, carbon molecular sieves, active carbon, and GDX-l02(a copolymer of styrene with divinylbenzene),were prepared, and their catalytic behaviors for propene hydroformylation were investigated and compared. The results showed that, over the carbon nanotubes-supported Rh-catalyst, C3H6 conversion and regioselectivity of butyric aldehyde (represented by n/i, a ratio of n-butyric aldehyde to its isomer, i-butyric aldehyde, in the products) were pronouncedly improved: the average turnover frequency(TOF) for the catalytic hydroformylation of propene was 0.079 s-1 at 393K, which was 2.1 times faster than that over the Rh catalyst based on SiO2, and the n/i ratio of the aldehyde products reached to 11.6, which was 1.9 times higher than that over the catalyst based on SiO2. The roles of six-membered C-ring at the surface of the carbon-nanotubes on the stability of the catalytically active Rh-complexes and of the tubular nano-channel on the spatiospecific seletivity of reaction intermediate state and butyric aldehyde produced were discussed.

Electrochemical Scanning Tunneling Microscopy (ECSTM) has been extended to characterizc polycrystalline silver electrode surfaces in iodide solution. Potential-dependent ordered and disordered structures of the silver electrode as well as the iodine adsorption layer have been observed to coexist on polycrystalline silver electrode surfaces, for the first time. A very special column arrangement of the iodine adsorption layer, similar to the so called "missing row" type of structure has been observed. Some columns of the iodine adsorption layer roll over from one place to another along with the time and changing potential. A proposed model has been given to better describe the structure. The highly corrugated and loose surface structure of the polycrystalline surface are responsible for this special phenomenon.

By using ab initio method, we have optimized 27 geometric configurations of the 10 valence-electron diberyllium diboride(B2Be2). A singlet tetranhedral like structure h is the most stable one at HF and QCISD(T)/6-311G** level. The stability order of 9 isomers is h>i>g>e>f>c>a>d>b. Further, by means of bond number parameter(BNP), Walsh diagram, energy gap and bond charges, we also revealed bonding properties.

Adsorption, aggregation and membrane structure of dye anions such as methyl orange(MO) and titan yellow(TY) on the cationic surface of vesicle bilayers containing schiff base were studied systemetically. The adsorption and aggregation were revealed through the wavelength shift of absorption maxinmm and precipitation produced in bianery mixture. Blue shift and red shift showed that the aggregate structure was H-aggregate for MO and J-aggregation for TY respectively. pH dependences of dyes in mixture systems indicated that the MO aggregates formed at high pH would be destroyed under low pH, which resulted from the cationic structure formation. TY aggregates were also disaggregated in considerable scale at low pH because of partial protonation, but strong red shift occurred at high pH. With temperature increasing, the aggregation of dyes would gradually be disintegrated following the change states of vesicle bilayer from gel to liquid crystal and finally to molecular dispersion. Differential Scanning Calorimetry(DSC) showed that the adsorption of dyes an action to decrease the phase transition temperature of vesicle and the differential spectra confirmed that the aggregate interaction of vesicle bilayer was weakened. 

 The Ln0.67Sr0.33Fe.Mn1-xO3(LSFMO)(0.05< x <0.33) systems have been synthesized by co-precipitation. The X-ray diffraction patterns indicates that these compounds are of single phase with rhombohedral structure. The resistivity of samples was measured in zero field and applied field (H=4000Oe) by a standard four-probe method. Large magnetoresistance (MR) was found in all samples. There is a resistivity transition peak in LSFMO (x ≦0.13) in which MR negative, the temperature (TP) at which the resistivity peak occurs decreases with the increasing of x. LSFMO (x=0.23) to which the large negative MR is still found is a semiconductor, It is unexpected that a peculiar alternative positive negative MR was found in LSFMO(x=0.33) which also is a semicondutor.

The mechanisms of all the addition reaction paths of 1,3-cyclohexa-diene with propylene have been studied by using ab initio UHF/6-31G* method. All geometries of the stationary points have been optimized. Stepwise and concerted processes are both possible for the reaction. The stepwise processes are most favorable in all reaction paths. The exo and endo products of the reaction can be formed through two mechanisms, i.e. the terminal double-bonded carbon of propylene attacks 1,3- cyclohexa-diene at first step or so do the center double-bonded carbon. The stepwise processes contain four reaction paths involving biradical intermediates. The calculated activation barriers of the rate determining steps of these paths are about 102~114 kJ•mol-1. Based on microcanonical transition state theory the canonical rate constants for the four stepwise paths have been computed by using data calculated at UHF/6-31G* level. The computational results show that the canonical rate constants for the reaction paths of forming endo product are larger than that for exo ones, and that the canonical rate constants for the reaction paths with the terminal double-bonded carbon of propylene attacking 1,3- cyclohexa-diene at first step are larger than that with the center carbon atom. The canonical rate constants of four stepwise paths are close to each other, so they are competing reactions.

Comparative molecular field analysis (CoMFA) was applied to the quantitative structure-activity relationship studies of growth hormone secreta gues. The final model is highly predictive, and the active conformation of this series of compounds was derived based on the model. This speculated active conformation was then imposed on the conformations of two known bioactive peptides by distance-comparision (DISCO) analysis to find a reasonable pharmacophore. It was shown that the amino group on L-692, 429 is a hydrogen bond donor while the tetrazole ring is a hydrogen bond acceptor, and, A ring and C ring are main hydrophobic cores.

The Monte Carlo simulation technique was developed to calculate the volume and surface area of molecules. In the fixed confidence degree, expected values within the specified confidence limit could be obtained. The result of this method was better than that of the Bodor al rithm method.

High temperature solid phase I of 2,2,3-trimethylbutane(C7H16)(TMB) was investigated by X-ray powder diffraction. The electron diffraction technique for observing the kinetics of phase transitions in the condensed matter has been applied to study the freezing of TMB clusters with diameter of~13nm. Cluster beams were generated from the supersonically expanded TMB vapor with mole fraction of 0.01 in neon carrier gas. The freezing evolution was monitored by electron diffraction in interval of 7-9 μs. Clusters with an average size of ~5,500 molecules were observed to freeze into the solid phase I at a nucleation rate of 3.5 × 1028 m-3•s- 1 at the freezing temperature of clusters, ～170K. The estimated growth rate of postcritical nuclei indicates that the observed nucleation in the present experiment corresponds to mononuclear freezing of the clusters into single crystals of solid phase I.

The local structure surrounding Mo and Ni atoms in a series of nickel-molybdenum-γ-Al2O3 catalysts promoted by P2O5 or TiO2 was investigated using EXAFS technique at Mo and Ni 1s edge. The analysis results show that the addition of P or Ti increases the metal dispersion under the condition of high Mo content and the octahedral structure in MoNiP catalysts is more abundant than that in MoNiTi. Moderate content of P2O5 facilitates the formation of the octahedral structure. It is also found that oxygen atoms of Mo-O bond in octahedral structure are easy to be substituted by S in hydrodesulphurization(HDS) reaction. In MoNiP catalysts the higher HDS activity might be caused by the abundance of octahedral structure.

PM3 method has been applied to study the tautomeric reactions of p-R-phenyltetrazoles. The results obtained show that these tautomeric reactions are all endothermic. The activation energies of the tautomeric reactions are 234.101(H), 234.311(CH3), 233.599(CI) and 232.031(NO2) kJ•mol-1, respectively. The reaction has higher activation energy when R is an electron-donating group, and has lower activation energy when R is an electron-attracting group.

Adsorption behavior of urea on silver electrode and the influence of thiourea on its adsorption in sulphuric acid solution were investigated by polarization curves and Surface Enhanced Raman Spectroscopy. Urea was found to under a condensation reaction on roughened silver electrode. Biuret was the condensation compound, and was adsorbed in the protonated form on the silver surface. Obvious synergistic mechanism between thiourea and protonated biuret was proposed.