Active free radicals formed by the photolysis of methyl substitute phenyldiazonium and their crown ether complexes have been studied by current spin trapps nitrosodurene (ND) and phenyl-t-butyl nitrone (PBN). The ESR results reveal that the methyl substituted phenyl produced therein can be easily trapped by ND and PBN.
The hyperfine splitting caused by hyperconjugation interaction of proton in substituted methyl group can be obtained from ESR spectra and their splitting constants are approximately equal to those caused by polarizing couple interaction between unpaired electron and protons in the same ring position, that is to say, a (p-H)≈a(p-CH_3); a(o-H)≈a(o-CH_3); a(m-H)≈a(m-CH_3).
For the different ring position, the constants a(H) are in the order of
a(p=h)≈a(o-H)>a(m-H)

The Crystal structure of 1,4-Biphenoxybenzene (Ⅰ) and 1,4-Bis (4-Methoxyphenoxy) benzene (Ⅱ) have been determined by X-ray diffraction method. For compound (Ⅰ) , the space group is P2_1/c; Its cell parameters are:a=5.876(2), b=7.832(2),c=6.5455(6)nm; β=95.33(3)~0; z=2.For compound (Ⅱ), the space group is Pcab; Its cell parameters are:a=6.017(1),b=7.577(1), c=3.6404 (5)nm;z=4.
The bond lengths,bond angles and molecular conformation indicate that:in these polyphenoxy benzene systems the conjugative polarization effect can not pass through the oxygen bridge to cover the whole molecule,
Such a strutctural feature explaines its small slope of the homolo us line for absorption peaks of polyphenoxy benzene series.

The equilibrium isotherms have been determined gravimetrically for xylenes in HZSM-5 and MgHZSM-5 zeolites at the temperature range of 298K—493K.The sorption of m-xylene in HZSM-5 is a physical adsorption which is diffusion-controlled and the activation energy is high.Its adsorption isobar shows two descending portions with an ascending portion between them.It was not found before for this system. Only at the temperature higher than 393K, can m-xylene molecules overcome the energy barrier and enter into the micropores of HZSM-5.
The amounts of sorption for p-xylene and m-xylene in HZSM-5 become closer each other when temperature rises. This may be the cause of that only equilibrium composition well be obtained if zeolite HZSM-5 is used as catalyst for the alkylation of toluene with alcohol or olefin. But for MgHZSM-5, the amount of sorption for m-xylene decreases sharply and p-xylene doesn't. This implies that the zeolite HZSM-5 must be modified in order to enhance the para-selectivity for the shape-selective conversion of single-ring aklyl aromatics.
The diffusivities of xylenes were measured by constant pressure gravimetric sorption methode at the temperature range of 313 K-433 K. The diffusivity of p-xylene is three orders higher than that of m-xylene in HZSM-5. The diffusive activation energies for px/HZSM-5, pX/MgHZSM-5 and mX/HZSM-5 are 16 kJ.mol~(-1), 17 kJ.mol~(-1) and 23 kJ.mol~(-1) respectively. The value of diffusivity for different crystal size of zeolite HZSM-5 is not substantially different.

The infinite dilution activity coefficients γ_i, partial molar excess enthalpies H_i~E and entropies S_i~E of C_1—C_4 alcohols have been measured in C_(16)—C_(23) normal alkanes, squalane and squalene by gas-liquid chromatography。 The obtained infinite dilution activity coefficients are all greater than unity. In the same stationary Iiquid, the values of γ_i follow the order: methanol>ethanol>n-propanol>n-butanol; n-propanol>isopropanol; n-butanol>isobutano>sec-butanol>tert-butanol.
It has been found that the activity coefficient of the same alcohol in squalane is greater than in squalene. The excess enthalpy of normal alcohols is greater than isomeric alcohols about 1.5 kJ.mol~(-1). The measured partial molar excess enthalpies and entropies are all positive. A linear relationship have been observed between the H_i~E and S_i~E values of the alcohols in the aliphatic hydrocarbon solvents, the results of which can be represented as
H_i~E-431 S_i~E+1620 (J.mol~(-1))

Under the condition of infinite dilution, the activity coefficients previously obtained have been treated by Kretschmer-Wiebe association model combining with Hiidebrand-Scatchard formula. In the binary systems of alcohol and alkanes,no relationship between the self association equilibrium constant and the number of carbon atoms of alkane has been found. The equilibrium constants decrease in the order: methanol>ethanol>n-propanol>n-butanol; n-propanol>isopropanol; n-butanol>isobutanol>sec-butanol>tert-butanol.
The carbon number and isomeric form of the alcohols have little effect on the calculated enthalpy of H-bonding formation, the average value of which is -24.2(+-)1.5 kJ.mol~(-1).
In the systems of alcohol and squalene, the calculated cross interaction coefficients l_(AB), which reflects the degree deviated from Hildebrand-Scatchard formula are negative, the absolute values of which are less than 0.1, and decrease in the order:
methanol>ethanol>n-propanol>n-butanol;
p-propanol>isopropanol;
n-butanol>isobutanol>sec-butanol>tert-butanol.

The phase diagram of ternary system PrCl_3-BaCl_2-LiCl has been investigated by means of DTA and X-ray diffraction analysis. It is found that there are 5 surfaces corresponding to the primary crystallization of PrCl_3, α-BaCl_2, β-BaCl_2,LiCl and Ba_3PrCl_9 respectively and 6 univariant lines related to the secondary crystallization in this system.The two reactions occurred in this system are:
L<=>LiCl+PrCl_3+Ba_3PrCl_9
E(72.1wt%PrCl_3, 2.8wt%BaCl_2, 25.1wt%LiCl; Temp.441℃)
L+△β-BaCl_2<=>Ba_3PrCl_9+LiCl
P(62.5wt%PrCl_3, 12.5wt%BaCl_2, 25.0wt%LiCl; Temp.490℃)
A compound, formed in the solid state, was found. The temperature of decomposition occures at 430℃.

The surface acidity of a kind of pillared interlayered clay molecular sieve with high thermal and hydrothermal stabilities (AIR)has been studied using titration and IR methods, and the experimental data obtained have been compared with that of HY and USY zeolites The acid site density of A1R amounts to about 0.45 mmoleg~(-1), which is 4—5 times less than that of HY and USY zeolites. There are two maximums on the acid strength distribution curve of A1R corresponding to two types of acid sites with medium (H_0=-3.0-0.8) and weak (H_0=3.3-4.8) acid strengths. In comparison with AIR, HY has more acid sites with medium acid strength and USY has additional acid sites with strong acid strength (H_0<-5.6). IR pyridine adsorption spectra of AIR show that the acid sites on AIR are mainly Lewis acid sites from the alumina pillars.
The catalytic behavior of pillared interlayered clay molecular sieve was compared with those of HY and USY zeolites. For acid-catalyzed reactions such as dehydration of isopropanol and conversion of cyclohexene, in which acid sites with wask and medium acid strengths take the part of active sites, the activities of AIR are lower than that of HY and USY. For cracking of cumene and decalin which are known as reactions catalyzed by strong acid sites the activities ofAIR arealmost negligible. The activity of AIR towards dealkylation of bulky molecules as 1,3,5-tri-tert-butylbenzene (0.94 nm) increases sharply and becomes comparable with HY and USY, and the product distributions of the three catalysts are different. This increase in activity and change in selectivity are unigue to pillared interlayered clay molecular sieves.

The adsorption isotherms of polyethylene glycols(PEG,molecular weights of 400,1000, 3350, 6000 and 20000), one polypropylene glycol(PPG) and polyoxyethylene -polyoxypropylene block co-polymers (L61, L64, and F68) from water onto the active carbon have been measured (at 25℃).The results show that all the isotherms are Lagmuir-type, and the limiting, or plateau adsorption is approached at relatively low concentration The limiting adsorption(g.g-1) of the polymers onto active carbon is constant apparently. For PEG series, the plot of molecular area at limiting adsorption (A) versus the number of ethylene oxide units in the polymer molecules (n_(EO)) is a straight line through the origin. For EO-PO co-polymer series the A-n_(EO) plot is also a straight line with same slop as that for PEG series, however, the straight line intercepts with area axis. The areas of EO and PO calculated from the slop and the intercept are 2.6 nm~2 and 2.9 nm~2, respectively. From these results, it is suggested that the adsorbed molecules lies flat on the active carbon surface.

The variation of Lyapunov exponent of Brusselator and Ore nator with controlling parameters of systems has been calculated. It is determined that the limitcycles of the two models are all produced by Hopf bifurcation according to the theory of stability of Lyapunov exponent.The conclusion of this calculation is the same as that of the analysis of linear stability for the behavior of Brusselator bifurcation. By analyzing the chemical background of Ore nator it is demonstrated that the major factors havingeffect on B-Z system bifurcation are the producing ability and producing rate of bromide ion. So all factors having effect on the producing ability and producing rate of bromide ion may affect the state of system. Therefore the effect of organic substrates, the catalyst of metal ion, pH and temperature ect. on B-Z reaction can be explaioned.

Fe_2O_3-K_2O binary catalysts prepared by high temperature calcination of the relevant mixtures and by KOH solution impregnation showed different catalytic behaviour in the reaction of dehydrogenation of ethylbenzene. The latter had longer stability period of the highest activity and shorter induction period. An impregnated multi-component catalyst, which was particularly prepared in our laboratory and had similar chemical composition to a well-known commercial catalyst(G-64I),showed that both the conversion of ethylbenzene and the selectivity to styrene were similar to G-64I although the impregnation amount of KOH corresponded to the fact that this impregnated catalyst had about 54 monolayers of K_2O on its surface. These facts indicated that the potassium promotor operated specifically on the surface of the iron oxide and that Fe_3O_4 was not the active phase of the catalyst as some authors had suggested. It was proved by using SEM, EDAX and XPS that, the Fe/K atom ratio on the surface of this impregnated catalyst increased obviously while the surface morphlogical structure changed simultaneously after this catlyst was operated for about 24 hrs. These suggested that a strong interaction between potassium promotor and iron oxide had occured on the surface and that the product resulting from the interaction should be the active phase of the catalyst. The XRD study at different temperatures showed that thte potassium promotor would reacted rapidly with iron oxide, thus forming K_2Fe_2O_4 in the temperature range 580—660℃, which was the usual operation temperature in the commercial production of ethylbenzene dehydrogenation to styrene. So, this paper suggested that the K_2Fe_2O_4 might be the active phase of the catalyst. Our experimental results could be satisfactorily explained according to this suggestion.

ESR studies were carried out in detail to investigate the changes of CuTAPP (cppper tetra-(p-trimethylanmoniumphyenl) porphine iodide) supported on active carbon during room temperature shelving and heat-treatment.Between room temperature and round 50℃, the resolution of the ESR spectra was found to vary with temperature and relative humidity reversibly. A mechanism of two-dimensional diffusion of the macrocyclic compound in the adsorbed liquid film was suggested to interprate the change in spectral resolution. The ESR spectra after heat-treat-ment at temperatures ranging from 150 to 600 ℃ were also reported and discussed briefly.

EXAFS spectroscopy has been used to investigate the dispersion of NiO onto the surface of γ-Al_2O_3. The comparison of the Fourier transformed EXAFS modulations of 7, 13, 18, 26, 35 wt% Ni/γ-Al_2O_3 and 13, 26 wt% Ni/α-Al_2O_3 suggests that NiO can disperse as a monolayer onto the surface of -γAl_2O_3. The Ni—O coordination distance which is near the Ni—O distance in NiO crystal suggests that the Ni ion interacts strongly with the oxygen on the γ-Al_2O_3 surface.

The variation of preoscillatory time and period with initial concentration of every substance in the phenol-BrO_3~--H_2SO_4 batch system has been studied. It is found that the oscillating behavior of the system is very strange: First, the period of the oscillation increases with time, as usual oscillations, then decreases with time in some ranges of concentration. This oscillation is called “period-doublemontonous” oscillation. The phenomena arc first published. The electrode potential of the system exalts likelycatatropy with the concentration of phenol. For BrO~-_3 and H_2SO_4 this phenomenon cannot emerge. This oscillation cannot be explained with FKN or OKN mechanism. Some details will be submitted later.

The crystal structure of Ba_2CdMoO_6 have been investigated by means of X-ray powder method, precise measurement of lattice parameters and other methods,using specimens prepared by solid state sintering method. We confirmed Ba_2CdMoO_6 belonging to cubic system at room temperature, with space group Fm3m. And we obtained that the lattice parameter is a=0.83354 nmat room temperature. Simultaneously we defined that Sr_2CdMoO_6 is new compound, it belongs to orthorhombic system and the lattice parameters: a=0.81931 nm, b=0.57694 nmand c=0.58406 nmat room temperature, The space group may be P_(mm2).

On the basis of a general functional relation representing the actual PVT properties of liquids, an equation of state of the van der Waals type has heen obtained. A new equation of correlation for prediction of excess volume and excess enthalpy has been derived from the above equation as follows:
V~E=R[((~n∑_(i=1)x_iV_i+V~E)~n∑_(i=1)x_i Φ_i)/(2PV~E/T+~n∑_(i=1)x_iV_iγ_i-H~E/T)-~n∑_(i=1)(x_i Φ_i)/γ_i]
where
Φ=(γVT/R)/(1/α+2T-2P/γ)
The results of calculation of its application to 77 binary systems with 148 experimental points show that, for prediction of V~E, it is better than the Flory method and in the wide scope concerned obviously much better than the Liebermann method and, for prediction of H~E, it is generally as od as the Pollin and Fried method. The equation of correlation proposed is simple in calculation, and can be applied to multi-component systems consisting of may liquids.

A general method to modify the empirical potential energy functions is proposed V(r)=W(r)V′(r) with correction function W(r)=exp{ρ[(r_e/r)~q-1]}. It has been successfully used for the modification of the Rydberg function.

We have studied the interaction of acetone and formaldehyde with terpolymer of formaldehyde and its methyl-,nitrile-and nitro-derivatives by MNDO and additive atom-atom potential method in three-hydrogen, two-hydrogen and one-hydrogen models. The results indicated that the supermolecules formed according to the three-hydrogen model are the stablest. It may affect the properties of matter.

The present paper presents the results of a structural study of the clean Ti(0001) surface carried out by analysis of Low-Energy-Electron-Diffraction intensities. The spacing between the top and the second atomic planes is 0.229±0.01 nm, i.e., slighly(-2.1%) contracted with respect to the bulk d_0 spacing of 0.234 nm.

A precision rotating-bomb combustion calorimeter in which thermistors were used as elements of temperature control and temperature measurement was constructed in our laboratory. The calorimeter was calibrated with benzoic acid of purity 99.999 percent. The energy equivalent of standard calorimeter system is 18.6376±0.0022 kJ.K~(-1). The precision of the experiment was 0.012% (shown in the form of 2s.d m) Detailed Washburn correction was made in microcomputer with programme designed by ourselves.

The electrochemical behaviors of thionyl chloride reduction in 0.11 mol dm~(-3) SOCl_2+ 0.1 mol dm~(-3) LiA1CI_4/DMF solution were studied with disc microelectrodes. For the first time, satisfactory Tafel plot with slope very nearly to 120mV/decade was obtained from steady polarization curve of thionyl chloride reduction. By analysis of the Tafel plot, it is clear that the first electron transfer of thionyl chloride reduction is a totally irreversible. The exchange current density of the first electron transfer of thionyl chloride reduction is 9.0×10~(-7)A.cm~(-2), andα value very near to 0.5.

In perfect mixture of CSTR, oscillation behavior of B-Z reaction system with gallic acid as organic substrates have been studied.We have found the regular oscillation curves, the sharp colur changes (purple red to blue) in reaction solution; and oscillation periods keep unchange. The dependence of oscillation behavior upon temperature is investgated. Oscillation behavior only take place in the temperature range 317 KIn this paper, we have also discussed the mechanism of this oscillation reaction. Some special regularity of this system can well be explained by modified FKN mechanism. The theonetical analysis is in accordance with the experiment results.

In this paper, the effects of the concentration of Hypocrellin A, solvents, acid, bases, dispersing agents and temperatures on the fluorescence spectra of Hypocrellin A have been studied in detail. It was proved that the action of solvents on Hypocrellin A is closely related to the characteristics of solvents.The proton transfer of the excited Hypocrellin A is weakened at low temperature. In order to compare with Hypocrellin A, Hypocrellin B has also been studied parallelly, consistent conclusions were reached. In addition, it was found out that Hypocrellin A and B can be acted as a new kind of fluorescence probes to study the multi-environment of micellar and biological macromolecular systems.