Exchange process between associating protons in the ethanol-water mixture system was described by NMR. A maximum appears in the dependence of exchange rate on the concentration of ethanol-water mixture system. The exchange rates, decreasing with prolongating storage period, indicate, that the more stable associated bodies have formed via hydrogen bonding between alcohol and water molecules.
The exchange process is very sensitive to the presence of contaminating H⁺ ions.
It is an important event to dvoid the presence of excess acids which may influence the stability of the associated body in ethanol-water mixture system.

1,3-Bis (trichlorosilyl) cyclohexane (Ⅰ) was synthesized by the addition of HSiCl₃ to cyclohexadiene-1,3 in the presence of H₂PtCl₆·6H₂0 in isopropyl alcohol. (Ⅰ) was ethanolysed to form 1,3-bis(triethoxysilyl) cyclohexane (Ⅱ) which was methylated and then hydrolyzed to form dimer, namely 2,2,4,4,11,13,13,-octamethyl-3,12-dioxy-2, 4,11, 13-tetrasilicon tricyclo-[11, 3,1,1^5,9] octadecane similar to octamethylcyclo-tetrasiloxane. The structure of these new silicon monomer and dimer were determined by ¹H-NMR, ¹³C-NMR and ²⁹Si-NMR.

A series of double ‘cubane’ clusters (Et₄N)₄[(MoFe₃S₄(SR)₃)₂Fe(SR)₆], R=Ph、o-tol、m-tol、and p-tol, were studied with magnetic susceptibility and ¹H NMR. Their magnetic and electronic structures were discussed. Isotropic shifts of both bridging and terminal ligands are mainly from contact interaction. Within a ‘cubane’ unit [MoFe₃S₄],the unpaired electrons are delocalized with strong antiferromagnetic coupling among the paramagnetic metal atoms. Two ‘cu-banes’ and a Fe(SR)6 bridge, form three practically uncorrelated magnetic centers.

The theoretical basis for the simulation of Electron Spin Resonance Spectra of S=1/2 system was given. The detailed calculation formulas were provided. A block diagram of the computer simulation program is given. The program is run successfully on IBM-PC computers.

Free radicals produced by the electroreduction of substituted phenyldiazo-nium RC₆H₄N₂⁺BF₄^-(R=F, Cl,Br,NO₂,OCH₃, or CH₃) in acetonitrile were studied with the combination of ESR spectroscopy with spin trapping technique.The results show that:
1. Radical RC₆H₄^·is produced during the electroreduction of RC₆H₄N₂⁺BF₄^-, and it can be trapped by PEN to form stable spin adduct (RC₆H₄-PBN)^·.
2. From the hyper-fine splitting constant of the spin adduct, the dihedral angle θ_β can be obtained and the effects of the same substituent in different ring positions of θ_β are in the order of
θ_β (o-R) < θ_β(m-R) < θ_β (p-R)

By use of spin trapping reagents, 2, 3,5,6-four metyl nitrosobenzene and phenyl t-butyl nitrone, in combination with ESR technique, the active free radicals were studied in the photochemical hydrogen abstraction reaction between benzophenone and twelve substituted amides, RC₆H₄NHC(O)CH₃ (R=CH₃, CI, Br, H, NO₂), C₆H₅N(R)C(O)CH₃ or HC(O)NR₂(R=CH₃, C₂H₅). The results show that:(1) for RC₆H₄NHC(O)CH₃,benzophenone abstracts H from nitrogen to form RC₆H₄NC(O)CH₃. (2)for C₆H₅N(R)C(O)CH₃ or HC(O)NR₂,benzophenone adstracts H from the methyl group linked with the carbonyl,from the carbony or from the carbon linked with nitrogen, respectively,to form C₆H₅N(R) C(O)CH₂, C(O)NR₂,C₆H₅N (CHR')C(O) CH₃ or HC(O).

The high order perturbation formulas of EPR parameters for d⁸ configuration in trigonal crystal field are derived.In our formulas, the contributions due to all excited states including singlets are considered. g_⊥ > g_|| or g_⊥ < g_|| and D > 0 or D< 0 are explained as due to the expanding or contracting of ligands along C₃-axis. The formula obtained is applied to deal with EPR parameters of NiCl₂ and NiSiF₆·6H₂0 crystals.The agreement of theoretical calculation with experiment shows that the theoretical calculated values are good.

Active radicals produced by photolysis of substituted zirconocene dichloride complexes (RC₅H₄)₂ZrCl₂(R=H,CH₃,C₃H₇,C₄H₉,C₅,H₁₁,C₆H₁₁) and hafnocene dichloride complexes(RC₅H₄)₂HfCl₂(R=CH₃,C₂H₅, C₃H₇)were studied by combining spin trapping technique with ESR spectroscopy.The results show that the photolytic mechanisms of substituted zirconocene and hafnocene dichloride complexes are the same as those of titanocene dichloride complexes. In other words the primary process of photolysis is homolytic cleavage of the M-(RC₅H₄) (M=Ti, Zr, Hf)π bond. Only in the former case the free radicals RCpMCl₂(M=Zr, Hf) can be trapped by PBN and ND.

High density polyethylene (HDPE) treated with plasma gases (including Ar, N₂, O₂ and air) in various conditions (including treatment power, treatment time and treatment pressure) was studied by ESR.
It was found that the radicals on the surface of HDPE, resulting from such a treatment, were rather stable and their intensity of ESR signal increased with the treatment power as well as the treatment time, but only slightly changed with treatment pressure. It was evidenced that the ultraviolet effect on the radicals of the surface of HDPE changed with conditions of plasma treatment. Their hyperfine interaction in the spectra of HDPE was interpreted.

The environment of B³⁺ in the non-crystalline Li₂O-B₂O₃-P₂O₅ system was examined by ¹¹B NMR. The existance of extreme values in conductivity and density etc, at P₂O₅/B₂O₃ ratio of 1, was explained theoretically with the additional help of Raman spectrum.

A program that facilitates the estimation of ¹³C-NMR chemical shift of ole-fines is presented. It is applicable ot small ones with satisfactory results. The program also provides a user with the probability of computing C-13 shifts of long-sequence polyolefines. Attention is paid to linear and branched structures resulting in the differences between the calculated and the observed values being reduced to ca. 2 ppm. In the case of cyclic olefines, the estimated values aer less than the experimental shifts, because of the cyclization effect. The program is written in FORTRAN IV-plus and BASIC languages, and run on a PDP 11/23 (or PDPll/24), or a microcomputer IBM PC/XT etc.

A method for one-dimensional heteronuclear chemical-shift correlation experiments on a FX-series NMR spectrometer is introduced.With the zero-intensity method proposed here,the chemical-shift difference of two protone for some CH₂ groups can be accurately determined by measuring several ¹³C-spectra, even on a spectrometer with low magnetic field.

This paper reports the structral elucidation of two compounds using pulsed NMR difference NOE technique.

A computer program is proposed for spectral analysis of NMR A_nB proton system. The formulation and calculation are simplified by use of group theory method. The acquisition of spectral parameters is based on sub-spectral method. Some typical RUN examples showing the reliability of this program are given.