A new method is presented for the calculation of octanol/water partition coefficients. On the basis of summation of atomic contributions, our algorithm, namely; XLOGP, also incorporate correction factors into the calculation. Multivariate regression analysis was performed on a training database of 1831 organic compounds with diverse structures to give the final model. The correlation coefficients for the whole set fitting is 0.968 and the standard deviation is 0.37. The result shows that our model is accurate enough for logP estimation in QSAR studies. Compared to other similar approaches, our method gives better results and is more convenient to use.

Four styryl pyrazine derivatives with different structure have been synthesized. The absorption and fluorescence spectra of these compounds in solvents with different polarity were measured. According to the spectral data and the possible conformation of these compound in ground state, a conclusion on the favorable conformation for the fluorescence emission of these compounds was confirmed.

Intramolecular energy-transfer and electron-transfer of porphyrin-phthalocyanine heterodimer, linked by piperazine, were investigated by absorption and fluorescencc spectroscopy. The efficiency of energy transfer(ФEnT) and electron transfer (ФET) were calculated. The results indicate that: In benzene, the main photophysical process is excited singlet-singlet energy transfer, while in DMF photoinduced electron transfer predominant. The ФET of this heterodimer in DMF is bigger than that of porphyrin-phthalocyanine heterodimers linked by oxygen or flexible chains. This may be ascribed to the "boat-form" conformation of piperazine, According to the CPK molecular model, porphyrin and phthalocyanine are held together in a face to face way, and the center to center distance between two macrorings is about 3.56 Å . It is suggested that conformational changes from "chair form" to "boat form" occurred subsequent to optical excitation in DMF.

The 1H MAS spectrum of a plastic organic solid is usually composed of a high-resolution component and a broadline component. The high-resolution component corresponds to a plastic phase, while the broadline component corresponds to the rigid Phase. The high-resolution spectrum of the plastic phase can be observed by the echo-MAS experiment with a long echo time; the high-resolution spectrum of the whole 1H system can be observed by the CRAMPS technique, mainly coming from the contribution of the rigid phase at usual temperature. It is shown that combination of CRAMPS with 1H MAS and echo-MAS is an effective way for studying the ratio of the plastic phase to the rigid phase, molecular structure and states of motion in organic solids.

Research on characteristics of colloidal aggregates with Lennard-Jones potential under shear has been carried out. The features included cluster size distribution, radial distribution function, fractal dimension and coordination numbers. It revealed that cluster size distribution approached to smaller size, radial distribution function and coordination number reduced graduately with increasing shear rates. When shear rates increased, fractal dimension ranging 1.9-2.4 increased first then decreased slightly. Shear did not change fractal dimension obviously, however (clusters were stretched at X (shear rate) direction and deviated from the X direction at high shear rates.

 Effects of many-body (by Sutton-Chen potential, SC) on colloidal aggregates have been examined and compared with that ot two-body (by Lennard-Jones potential, LJ)Some characteristics were similar in both SC and LJ systems such as potential energy increased, and the number of particles in a cluster decreased with increasing shear rates; clusters were stretched remarkably in shear (X axis) direction and the longest axis of clusters deviated from X axis under stronger shear held; etc. Their differences were also obvious : arrangement of particles in SC system was more reasonable than in LJ system so that the potential energy in SC system was lower 1-3 dimensionless energy units, thereby clusters in SC system were closer and their fractal dimension higher; dependent of petential energy for particles, average cluster size and fractal dimension on shear rates was weaker in SC than in LJ systems; morphologies of clusters were occasionally changed to some extent.

The pyrolysis reactions of ten mononitrate esters have been studied by using SCFAM1-MO method. The effect of alkyl substitution on the mechanism of reactions is discussed. UHF calculations show that homolysis of O-NO2 bond into two radicals RCH2O•and•NO2 has lower activation energy and is the main way of pyrolysis. However, RHF calculations indicate that breaking of O-NO2 is a α-H transition elimination reaction with products RCHO and HONO and quite high activation energy, and can't occur when there are more than two alkyl substitution groups on α-C. The cleavage of C-O bond has also been studied by UHF and RHF calculations.

 The self-assembling process and electrochemical behavior of (4-ethoxy-4'-N-(2"-mercaptoethyl) aminocarbonyl-azobenzene monolayer on gold were investigated by cyclic voltammetry and contact angle measurements. The apparent electron transfer rate constant ks was found to decrease with increasing the surface coverage. Taking account of the structural change associated with the reduction/oxidation process of azobenzene to hydrazobenzene, the unique decrease of apparent electron-transfer rate constants could be well understood by the inhibition on such a molecular structure change of close packing film structure, which may lead to an increase of activation free energy for the reduction/oxidation process.

Monolithic β- FeOOH aerogels which consist of rodlike particles with lengths of about 18nm and diameters of about 5nm were prepared from aqueous ferric chloride and sodium hydroxide. Material synthesis involved preparation of iron polymer aquogel followed by supercritical drying. The effects of the molar ratio of OH- /Fe3+ on the density and the specific surface area of the aerogel samples were studied. The aerogel samples were characterized with BET, TEM, XRD and Mossbauer techniques. The results show that the aerogel samples were coherent nanosized porous monolithic solids which consist of β-FeOOH ultrafine particles. By increasing the molar ratio of OH- / Fe3+. the final density of the aerogels increased with a concomitant decrease specific surface area.

A chemical kinetic method based on the kinetic expression of the second-order reaction on fractals is used to determine the spectral dimension of fractal surfaces. The method can conveniently give the spectral dimension by analyzing the relation between reactant concentration and reaction time (ct～t). The spectral dimension of the Diffusion-Limited Aggregate (DLA) is obtained by Monte Carlo simulation of the desorption process of chemisorbed hydrogen from DLA, and it is in agreement, with that in literature. Also, the spectral dimension of a real catalyst 12% Ni/Al2O3 is obtained by the method.

The colloids of Eu(DBM)3 and ultrafine particles Eu(DBM)3 were perpared. The particle sizes determined by X-ray and by TEM measurements were in 7-30nm range. Their UV absorption and fluorescence spectra were compared with each other and with those of the solid sample. It was shown that the 5D1→7 F1,2 transition was observed in the colloids of Eu(DBM)3 at room temperature. The increase of the excited-state S1 and T1 energy, the peak positions of UV absorption shifted to shorter wavelength, the changes of the absoprtion coefficient with decreasing size were observed.

It was found that the catalyst aged under microwave radiation is much more active for H2O2 decomposition than that aged under conventional heating. Characterization of the catalysts showed that the above result could be interpreted by a hypothesis that orientation of ions (Co2+, Fe3+) in the solution was restricted by microwave electromagnetic field so that the surface of the catalyst is irregular.

A thermometric method in which the heat of reaction is used as a quantitative measure of terminal OH groups in polymers has been in routine use. We use DDIE to determine the terminal OH groups in polyglycol and telechelic polybutadienes by the acetylation reaction of perchloric acid with acetic anhydride. The result is in good agreement with that of chemical titration, thus showing high reliability of DDIE in polymer end-group determination.
The method takes less than 5 minutes to carry out. The advantages of DDIE are simplicity, speed and also a repeatability is good.

The heat output of the plant cells-Chlorella vulgaris has been determined using the LKB-2277 bioactivity monitor. The metabolic thermokinetic equation is
dP/t = k0, k0 = 0
The experimental results indicate that there is a linear relationship between the meatbolic power and the cell concentration and that the heat output produced by a single cell's metabolism depends on the cell concentration and is inhibited by the increase of the cell density. It presents a special kind of space effect.

The heat production of Wistar rat polymorphonuclear leukocytes (PMN) was measured by an LKB 2277 Thermal Activity Monitor. When PMN were activited with phorbol-12-myristate13-acetate (PMA), the respiratory burst was recorded by greatly incr eased heat production. Experiment was also carred out in the present of the inhibitor, Total Flavonoids of Lycium Barbarum L. (TFL). The respiratory burst heat production peak was disappeared, but the heat production curve was higher than that of PMA because TFL increased the metabolic activities of PMN.

Uniform colloidal particles of BaCO3 are produced in the system of n-octanol, BaCl2 and Na2CO3 aqueous solutions under the action of hexadecyltrimethyammonium bromide(CTAB) by the methods of single-emulsion, double-emulsion, solution and gas-blasting. The key factors, which determine the size, shape and uniformity of the particles, as well as the suitable methods to prepare uniform colloidal particles are figured out by comparing different (water-oil) phase ratios, kinetics of particles' growth and different methods of preparing hydrophobic sols.

 The catalyst for dehydrogenation of diethylbenzene(DEB) to divinylbenzene(DVB) was studied. Potassium-promoted iron oxide catalyst was mainly used for ethylbenzene dehydrogenation. If potassium alkli or salt was used directly as promoter, it was noted that the loss of potassium component from the surface of the catalysts pellet result in deactivation. When potassium promoter was added as kaliophilite(KAlSiO4). It was shown that the latter way of adding potassium promoter not only keeps the depression of carbonaceous deposits but also controls the loss of potassium component(the value of loss of potassium component has been reduced three times) , thus making the catalyst having a higher dehydrogention activity.

p-dimethylaminobenzonitrile (DMABN), a typical dual fluorescent flurophore (TICT flurophore), was used as fluorescent probe. The microenviromental property of twelve methyl modified β-cyclodextrin(methyl β-CD) was compared with that of β-cyclodextrin (β-CD). Results showed that the polarity of the cavity of methyl β-CD is lower than that of β- CD, and the capacity of methyl β-CD inclusion with DMABN is stronger than that of β-CD inclusion with DMABN.

Fe2(MoO4)3 ultrafine particle catalyst has been prepared successfully by the sol-gel process at lower temperature. The influences of preparation conditions and thermal treatment conditions on the morphology and structure of the ultrafine particle catalyst has been studied by using TEM, DTA-TG, FT-IR, XRD and BET surface area measurement methods. It is shown that the BET surface area of Fe2(MoO4)3 ultrafine particle prepared by sol-gel method is much larger than that of Fe2(MoO4)3 prepared by coprecipitation method. For the preparation of the well-distribuated Fe2(MoO4)3 ultrafine particles with the size in the range of 40-80nm, the optimum conditions are : treatment temperature <=673K, L/M (Citric acid/Metallic ions)=0.3 and pH<1.0.

The pendent drop or standing bubble method is applied to measure the interfacial tensions between water and nonpolar fluids (n-hexane, n-heptane, nitrogen, oxygen and methane) up to 473K and 220MPa. The high pressure autoclave with t wo visual windows and the auxiliary equipment are described. The sizes(ca 2mm) and shapes of drops or bubbles are recorded with microscope and video camera. The use of digital image permits fast, precise determination of the contour parameters. The densit y values of the liquids or gases have been chosen from literature. A special program is proposed to calculate the interfacial tensions automatically from drop shape at given temperature and pressure. The interfacial tensions σ12 increase with pr essure for the two liquid-liquid systems, but decrease with pressure for the three gas-liquid systems.

In this paper, a set of ATP sensitive K+ channel openers (KCO), whose structure are different, were investigated with the aim to develope our previously defined KCO's pharmacophore model. To validate the effectiveness of the pharmacophore model, A comparative molecule field analysis (CoMFA) was proceeded, aligning the molecules according to the requirernent of the model, and good results were obtained. This pharmacophore model may be a start point to design new KCO compounds.

Photocatalytic reduction detoxification of Cr6+ ion in TiO2 dispersion, photocatalytic redox synergism in the presence of Cr6+ and some different organics have been studied. The implication for the application of photocatalytic redox decontamination in the real pollution system of co-existed toxic metal ions and organics are presented. The results indicate that Cr6+ can be reduced and detoxified remarkably with TiO2 as catalyst. The reaction atmosphere has negligible ef fect on Cr6+ reduction. Cr6+ reduction is in accord with L-H kinetic equation. Some alcohols, acids and aromatic organics exhibit promotion effects on Cr6+ reduction, but some alkanes and chloro substituted organics exhibit inhibition eff ects. These different effects are mainly dependent on their structure but not number of the carbon atoms, this means that electronic and structural characteristics of different organics are important factors in synergism.

 Single crystal of PbCuP2O7 has been prepared by the conventional solid state reaction method. Its crystal structure has been determined from X-ray four-circle diffractometer data: P21/n, a=5.381(1), b=8.205(2), c=12.570(3)?, β＝90.49(3)°,Z=4, R=0.054 for 1311 structure factors and 101 variable parameters. The frame-work of PbCuP2O7 consists of corner-sharing CuO5 square pyramids and P2O7 groups forming large tunnels running along α-axis. Pb atoms are located in the pentagonal shaped windows, which are formed by the edges of two square pyramid and three PO4 tetrahedra.

 The aim of this paper is to study how to treat the experimental adsorption isotherms by the conventional Type－I isotherm theories in order to acquire the required information of the adsorption system under supercritical conditions. The study was carried out on manipulation of a set of adsorption data of supercritical hydrogen on activated carbon AX－21 over a temperature range of 77－298K. The results show that the Langmuir equation can well model the experimental data, but cannot provide any reliable information about the adsorption system considered; the Virial equation cannot model the whole set of data satisfactorily, but it can give Henry's law constants reliably， from which isosteric heat of adsorption can then be precisely determined. Some inspection of the adsorption mechanism was made on fitting data to Dubinin-Astakhov equation. Although this equation can best model the experimental data, the reality of any physical quantity evaluated from it might be doubtful since the parameters in the model interact each other during regression and some quantities in the equation are ill－defined under supercritical condition.

The effects of ZrO2 modification of γ-Al2O3 on the desorption-renewal properties of surface oxygen species and the reduction behavior of copper species on CuO/γ-Al2O3 were studied by TPD-MS and TPR methods, and its activity for CO oxidation was examined. The results indicated that the presence of ZrO2 could promote the desorption of surface oxygen species and the reduction of copper species on CuO/γ-Al2O3 and thus increasing the activity for CO oxidation. In addition, it was found that the desorptibility of oxygen species and the reducibility of copper species on γ-Al2O3 or ZrO2-Al2O3 were affected by variation in the conditions of thermal treatment.

 According to the phenomenon theory of micellar solution, the Gibb's free energy of salt added C8-lecithin micellar solutions is deduced using Debye-Huckel's and Kirkwood's theories of electrolytes. The mechanism of ion-amphiphilic molecule interaction, and the variation of the critical temperature of phase separation in the solutions vs ionic strength are also described with the Gibb's free energy model. The model consists of a linear term of ionic strength, contributed from ion-dipole interaction, and a square root term of ionic strength, contributed from ion-ion interaction. A formula which describes the critical temperature of phase separation is also deduced from the Gibb's free energy model. The formula appears as, T’c=Tc- A1I1/2+A2I ,and agrees well with the experimental data of both monovalent and divalent salt added micellar solutions.

UV pulsed laser ablation of tantalum oxide at 355nm has been investigated by angle-resolved time-of-flight quadrupole mass spectrometric method. The measured TOF spectra show that the main ablation neutral products are O, Ta, TaO and TaO2, and the corresponding ionic species are observed with increasing the laser fluence. Their TOF spectra can be fitted by multicomponent Maxwell-Bolztmann distributions with a center-of-mass velocity, and the translational energies of the ionic species are independent on the laser fluence under our experimental conditions. The angular distributions of the ionic and neutral ablation products can be fitted by the expressions of acosnθ(n≈26 ) and acosθ+bcosnθ (n≈27), respectively. Possible mechanisms for the production of these species in the UV laser ablation process are discussed.

The generation of nano-size particles by chemical reaction is a new method with advantages, which provides nano-size particles in a form of thin film called particulate film. Since the chemical reaction takes place at surface, it would be effected by the physicochemical properties of the gas phase, liquid phase and surface phase. In this work, light reflectivity measurement, transmission electron microscopy, UV-visible spectroscopy and electron diffraction technique have been used to investigate the effects of the properties of gas phase on the particulate film formation of ZnS.

Based on the diffusion action of gallium in silicon and SiO2 ,a diffusion model of gallium doping in bare silicon system and SiO_2/Si system is first presented in this paper ,the gallium doping effect in the two systems is analyzed theoretically. Experiments and applications have proved that the use of the open-tube gallium deffusion in SiO2/Si system can substantially improve diffusion quality and device characteristics .

The copolymerization of CO with ethylene was studied with high pressure in situ IR technique using (DPPPr)Pd(p-CH3PhSO3)2 as the catalyst precursor. Two IR absorptions of carbonyl groups were observed at 1900cm-1 and 1810cm-1 under pure CO ambience, which proved that CO was coordinated with Pd(Ⅱ) under pure CO ambience. Three IR absorptions were observed at 1638, 1616, 1970cm -1 under real reaction conditions, which could be assigned to three intermediates (1,2,3) respectively, indicating that the insertion of CO into Pd-OR bond was probabaly one of the main initation path ways in alcohol solvent.

 Nickel-palladium film on p-Si prepared by potential -controlled electrodeposition has much better adherence than that deposited by other methods .To reveal the reasons of this effect, X-ray photoelectron spectroscopy (XPS) combined with Ar+ sputtering was used to investigate the interface of NiPd /Si. The results showed that dramatic interdiffusion of Ni, Pd and Si had occurred at atmospheric temperature. On the XPS spectra of nickel and palladium , there are two kinds of binding energy , contributed by pure metals and metal silicide respectively. NiSi, PdSi and Pd2Si were formed at the interface. Both of the electric field on the surface and the H atoms in the metal lattice have the possibility to promote reactions between nickel or palladium and silicon .

 Study of the phase chemistry relation of quaternary system CsBr-SmBr3-(13%)HBr-H2O at 25 ℃ is carried out in order to investigate the reaction of CsBr and SmBr3 in hydrobromic acid. A new compound 5CsBr.2SmBr3.22H2O is discovered and obtained in the system. X-ray powder diffraction, thermal analysis (TG and DTA) and polarization character of the new compound obtained from the system are investigated. Meanwhile, the synthetic mechanisms of compounds (CsSm2Br7, Cs3Sm2Br9, Cs3SmBr6 and Cs2SmBr5) are suggested on the basis of phase chemical relation of the system.

 Fluorescein ethyl ester as a model and four dyads of Fluorescein and Anthroic acid linked with different length spacer were synthesized and characterized. They were put in bilayer membrane and on SnO2 coated substrate, The photoinduced voltaic responses were observed and compared when fluorescein was excited using visible light. It was found that the dyads have higher responses than the model, and the dyad with a butylene spacer (n=4) has the highest response. The results and related mechanisms were discussed.

The stability of different crude oil emulsions from ASP flooding production well is studied by the method of a stirred tank. The demulsifying of crude-oil emulsion by different demulsifying agents is discussed. The breakage of the crude oil emulsions from the well PO11 by the different types and concentrations of the emulsifying agents is also discussed. The breaking mechanism of the demulsifying agent is described microscopically.

The influence of adsorbed CO diffusion on the first order phase transition point (y2)of CO oxidation based on Langmuir-Hinshelwood mechanism was studied in detail by Monte Carlo simulation. It was found that CO diffusion increased the value of the first order phase transition point(y2) and when the ratio(k) of diffusion probability of adsorbed CO to adsorption probability of CO is 100, y2 is equal to 0.642. The correlated y2 value is in good agreement with the theoretical result(0.65) obtained by Mai when k approaches to infinity large.

 The kinetic processes of the photoionization and dissociation of 4H-furan have been investigated by using synchrontron radiation. The IP of 4H-furan and APs of other ions are gotten from the spectra, the possible channels of dissociative photoionization have been annalyzed. A serices of stable clusters composed of (THF)n. (H2O)n-2H+ (n=2,3,4,5) are present in the MS and the possible structures of the clusters are given.

A photoacoustic detection system consisted of a piezoelectric cylindrical tube transducer is applied to measure the photolysis of Coenzyme B12 (5'-deoxyadenosylcobalamin, AdoCbl) in methanol to obtain the quantum yield, Ф. The value of 0.20±0.05 is in agreement with that obtained in aqueous solution by other authors with an optical method.