ld nanoparticles were covalently attached to the thiol-terminated surface, which was created by aqueous silanization of the single crystal silicon substrate with 3-mercaptopropyl-trimethyl-silane(3-MPTMS). This paper reports the first evidence for Au-S bonding between the ld particles and the surface thiol-groups given by the angle resolved XPS measurements.

With 50nm ld nanoparticles as seeds, a series of spherical monodispersed ld nanoparticles(size from 60nm to 160nm) were obtained by surface autocatalytic reaction. The ld sols were characterized using transmission electron microscopy(TEM) and UV-Vis spectrometry. The size of nanoparticles can be conveniently predicted by controlling the molar ratios of the total ld species in solution to that in seeding sols. The morphology of resulted ld nanoparticles was found depending on the reagent-adding sequences.

We have synthesized the C60 aminonitrile and dicyandiamide derivatives and their Fe(Ⅲ)complex. The second-order hyperpolarizability γ for these derivatives have been measured by using the femtosecond optical Kerr effect at 810 nm. The relation between the value of γ and the characteristic of charge transfer has been investigated.

The resonance-enhanced multiphoton ionization (REMPI) spectrum of 2 butanone in 467～488nm was obtained using multiphoton ionization—time-of-flight mass spectrometric technique and dye laser. By analyzing the spectrum, we have ascertained that the strongest peak in the REMPI spectrum,62305cm-1,could be attributed to one component of the 3d Rydberg transition, the peaks in 63291～63898cm-1 are mixed Rydberg valence vibronic transitions, and 63291cm-1 is the 0-0 transition of the state.

Synthesis works on Ag clusters in ordered phase of O/W, W/O and LC are reported. Stabilized Ag particles and gel can be synthesized from high concentration of AgNO3 reduced by N2H4•H2O applying W/O/W or LC. The gel and particles were characterized by UV-visible spectrum, X-ray diffraction and transparent electron microscopy. We found the layer structure surrounding Ag clusters which illustrateds the double layer ordered phase coatings of surfactant and auxosurfactant.

The chemical reactivity of β-propiolactone with different nucleophiles is studied by use of atom bond electronegativity equalization method. According to our study, the Fukui function is not the only factor to determine the selectivity of a chemical reaction, while the principle of hard and soft acid and base in a local sense can be used to understand this kind of reactivity.

Ab initio calculation, intrinsic reaction coordinate (IRC) tracing and topological analysis of electron density have been carried out for the reaction of atomic O(3P)with CS2. Minima and saddle points leading to the formation of CS+SO, S+OCS and S2+CO were found. Stationary points were located at the UHF/6 31G*level and the energies were corrected at the UMP2/6 31G*level. Stationary points on each one of the three reaction channels were confirmed by the IRC tracing. Topological analysis of electron density was employed for investigating the changes of chemical bonds in the reaction process. The calculated result reveals that all minima and transition states have Cs symmetry, i.e., the Cs symmetry is maintained on the whole pathway for every reaction channel. The reaction channel (1), O+CS2→CS+SO, is easier to be achieved than the other two because of its low energy barrier. It is in agreement with the experimental observations. The detailed information for the reaction mechanism has been discussed.  

The oxidation process of pure tin and tin samples doped by Ga, S and Cu with different particle sizes has been investigated by DTA,TG and XRD methods. Results revealed that 0.1%addition of Ga markedly influenced the oxidation process of tin. In the heating process, SnO which presents as a more compact film formed on the surface of the particles protected the particles from oxidation to certain extent. In the other cases, tin oxidized into SnO2 directively. S addition deteriorated the oxidation process and lowered the oxidation temperature.

Ni Mo ultrafine particle samples have been prepared by sol gel method with citric acid as complexant. DTA, BET, XRD and LRS have been employed to characterize the structures of the samples obtained by calcining the Ni-Mo gel at various temperatures. The results show that when the Ni Mo gel is calcined in air at 210 ℃, citric acid reacts violently with O2, it produces a flash heat and results in an aggregation of the Ni-Mo particles. When the gel is calcined in ar n, citric acid is removed mildly and NiMoO4 ultrafine particles are formed. After calcined at 500 ℃, the ultrafine particles grow up with a decrease of BET surface area from 51.5 m2•g-1 to 25.0 m2•g-1.

Electrochemical and spectral properties of phenylhydrazine hydrochloride (PH) in aqueous solutions in the presence of α-cyclodextrin (α-CD) were investigated. Spectral results indicate that phenylhydrazine hydrochloride can form 1∶1 inclusion complex with α CD in aqueous solutions. The formation constant of the complex, Kf=178 mol-1•dm3,was evaluated by UV spectrometry. It was observed that the light and oxygen sensitivity of the inclusion complex is much lower than that of the uncomplexed PH, this can be used to improve its storage and handling, and also widen its applications in pharmaceutical industry .Furthermore, it was found that its electrochemical oxidability in aqueous solutions can be greatly suppressed in the presence of α-CD.

The conformational properties of Met-enkephalin (Tyr-Gly-Gly-Phe-Met) were investigated by high temperature quenched molecular dynamics simulations in vapor. Each of these selected structures were then analyzed according to their backbone(φ,Ψ) conformational distributions and sorted into 13 families by computing the rms difference between the Cα-C backbone fragments of each residue over all the structures. Selected lowest energy conformations from each of 13 families were thoroughly energy minimized. The results of simulations show that Met-enkephalin is a flexible molecule. It shows a type Ⅰβ-turn, with the Gly2 carbonyl forming a hydrogen bond with the Met5 amino proton and a type Ⅱβ turn, with the Tyr1 amino proton forming a hydrogen bond with the Phe4 carbonyl. The multiple fit were carried out for all of the 13 conformers with morphine(9 atoms on the pharmacophore groups). F2 and F6 were the most similar to morphine. The rms were 0.0504 nm and 0.0726 nm. The results of simulations also show that Tyr amino N corresponds to N on piperidine ring in morphine, Tyr phenol corresponds to the phenol in morphine, the aromatic ring of Phe corresponds to the cyclohexene ring in morphine. The distances between the three pharmacophores, d1 (Tyr N to Tyr OH), d2 (Tyr N to Tyr du1), d3(Tyr N to Phe du2) and d4(Tyr N to Phe du2) were found to be about 0.8, 0.5, 0.7-0.9 and 0.5 nm, respectively, the corresponding, distances of morphine were found to be 0.7697(N18 to O6),0.5143(N18 to du25), 0.3962(N18 to du24)和0.5566(N18 to O15)nm. Therefore, they may be acted on the same receptor. This model should aid in pharmaceutical design of peptide and nonpeptide ligands with opioid.

The hydrogen bond structure and diffusion behavior of water at supercritical states were investigated by MD simulation. A great number of new simulation data of radial distribution functions, hydrogen bond structures and diffusion properties of supercritical water were obtained. The hydrogen bond interaction between supercritical water molecules decreases dramatically whereas the diffusion properties of supercritical water increase by two orders of magnitude.

The Pd film nano-materials supported on glassy carbon (nm Pd/GC) were prepared under conditions of electrochemical voltammetry. STM images illustrated that the Pd film consists of crystallites which are composed of nano-particles of Pd with average size at around 6nm,and are of layer shapes. CO adsorption on nm-Pd/GC electrodes manifested abnormal infrared effects (AIREs), i.e., the inversion of IR band direction and the enhancement of IR absorption. In comparison with CO adsorption on massive Pd electrode, an enhancement factor at 42.6 was measured on a nm-Pd/GC electrode of film thickness at 12.2nm.The nm-Pd/GC electrode possesses particular properties for hydrogen reaction. It was revealed that, in contrast to hydrogen absorption by massive Pd electrode, the surface processes of hydrogen adsorption desorption become the dominant reaction on nm-Pd/GC electrodes. The results demonstrated also that both the AIREs for CO adsorption and the particular properties for hydrogen reaction depend strongly on the thickness of Pd film, and can be consequently assigned to the nanometer size effect of Pd film materials. The present study has introduced important significance for further studies on surface electrochemistry and electrocatalysis. 

The reaction process of VK1 and isopropanol radical has been investigated by using pulse radiolytical technique. It has been found that the reduction states of VK1 exist in two forms under different pH conditions, that are VK1H•(pH < 5.4) and VK1-• (pH > 5.4), their maximum absorption peaks are 370 nm and 390 nm respectively. Selecting MV2+as the refereance, the one electron reduction potential of VK1 in N2 saturated aqueous isopropanol acetone mixed solvent and in N2O saturated water-isopropanol has been determined as -266 and -279mV respectively.

Monte Carlo simulation techniques were used to study the microscopic structure of mixtures of hydrogen, carbon monoxide, methanol and hexane with different densities. The results showed that aggregation between methanol molecules is more distinct than that between hydrogen molecules and between carbon monoxide molecules with different densities. Hexane distribution densities around hydrogen, carbon monoxide and methanol were similar when the solution density was low, and hexane distribution density around methanol was large than that around carbon monoxide and hydrogen with solution density decreasing.

A serious of zeolites Y of high Si/Al and high crystalline have been prepared by treatment with silicon tetrachloride vapour. Adsorption isotherms for n-Hexane have been measured by vacume gravimetric on a series of samples at various temperatures. The relationship between uptake of sorbate on a series of samples and dealumination extent and temperature have been obtained. Differential heats of adsorption, differential entropies and heat capacities of adsorbed substance have been calculated from the isotherms. The nature of surface and intracrystalline porosity of dealuminated zeolite Y have been further considered from the results of our experiments.

The reaction of •Cl+CH(CH3)2•CH(CH3)2+HCl was studied by a 3 atom quasiclassical trajectory calculation. The results indicate that the angular distribution of HCl molecule does not show apparent anisotropy, and HCl is in the vibrationally ground state and the first excited state. The reaction trajectories show that a short lived collision complex is formed during the reaction process, so the angular distribution of product molecule does not show some intense scattering direction.

BaKPbO and BaKPbBiO single crystals were electrodeposited on anode by the molten salt electrochemical method using KOH/KNO3 as flux. It is found that the K content decreases when the KNO3 concentration in the flux increases. On the other hand, when the KNO3 concentration in the flux is constant, the K content increases as the Bi content in the BaKPbBiO crystals increases. The magnetic susecptibility measurements show that Ba-K-Pb-Bi-O crystals are superconducting while BaKPbO crystals are not. XPS analyses reveal that the M(M=Pb, Bi)6s-O2p valence band moves toward the Fermi level when the Bi content in BaKPbBiO decreases.

The positron lifetime spectra were measured as a function of dehydration time for the ultra stable Y zeolite(USY) samples unheated, heated at 180 ℃in air and at 500 ℃in vacuum respectively. All spectra were resolved into five components. The intensity of the fifth component I5 is sensitive to the structure of the second pore in USY. The experimental results indicate that long time pumping with 0.5 Pa vacuum can dehydrate, but heating the sample at 500 ℃is a more effective method of dehydration for the second pore in USY zeolite.