Responses to 1-2 pulses for NQR spin system of I=1 with small energy level separation are examined with fictitious spin -1/2 operator formalism.Because the interaction of nuclear spin and radio frequency field in the framework of nuclear quadrupolar interaction is time dependent, time evolutions of density operator are calculated with Dyson time order operator.

H-and Y-crosslinks formed by photoinitiated crosslinking of dodecane,squalane,isooctane and 1-hexene as the model compounds of low density polyethylene in the presence of benzophenone as photoinitiator have been studied for the first time by solution state ¹³C NMR spectroscopy. The quantitative studies show that the types of crosslinks depend on the sorts of the model compounds.H-and Y-links are both formed for photo crosslinked dodecane and isooctane samples Whereas only H-links were detected for the crosslinked squalane.On the other hand,the double bond of unsaturated hydrocarbons such as 1-hexene can be opened to form Y-link by the reaction between a terminal vinyl group and an alkyl radical.These results are in good agreement with those obtained from low density polyethylene and give new evidence for elucidating the formation of the crosslinks in the photo cosslinked polyethylene.

Complete ¹H and ¹³C NMR resonance assignments were carried out for betulinic acid 7', 8' -dihydroxycinnamate. In addition to conventional 1D NMR methods, 2D shift-correlated NMR techniques (¹H-¹H COSY, ¹H-¹³C HETCOR and COLOC) were used for the signal assignments.

ESR and spin trapping technique were used to study radical generation in living animal dogs during the course of myocardial ischemia and reperfusion.ESR analysis showed that the species trapped by PBN from coronary veinous blood is OH radical,which provided directly an evidence supporting the active oxygen radicals hypothesis of ischemia-reperfusion cell damage.Further experiment had found that a kind of saponin drug is an effective scavenger and has a capability for protecting myocardial cell membrane on radical damage.

In this paper,on the base of NMR study of 0,0-(2,2'-binaphthyl)-N-(α-benzylethyl) phosphamidate and 0,0-(2,2 binaphthyl) chloride,of fered the theoretical basis of determining optical purity of 2,2-dihydroxy-1,1-binaphthalene by using ¹H and ¹³P NMR of these two compounds.

The chemical structure of linear dihydropyranocoumarins Pd-C-I was studied in detail by COLOC spectrum as well as ¹H-¹H COSY spectrum.It was observed that the attached position of acyl group of Pd-C-I can be determined by correlated cross peaks in COLOC spectrum.The result shows the significance on structural studies and discussion of structure activities relationship of linear dihydropyranocoumarins.The mistakes in the literatures about the assignments of some signals of carbons and protons were also revised.

This paper deals with the studies of 2D NMR spectra of disaccharide moiety of a flavonol-3-O-xylosyl-rhamnoside isolated from the aerial parts of Epimedium koreanum.The interlinkage of the biose was determined to be β-D-xylopyranosyl-(1→2)-α-L-rhanmopyranose.A simple NMR criterion was proposed for flavonol-3-O-xylosyl(1→2)-rhamnoside.

The ³¹P NMR spectra of O,O-di(2-ethylhexyl) dithiophosphoric acids (DDPA)prepared under various reaction conditions are reported.The variation of the components of DDPA synthetic products and reaction mechanism are studied.

¹H NMR Meerwein's ester (1,3,5,7-tetracarbomethoxybicyclo[3, 3, 1] nona-2, 6-diene-2,6-diol) (I) has been measured as a function of the mole fraction of benzene in the mixed solvent of bezene and caron tetrachloride. As the mole fraction of benzene in creases, the chemicalshifts (δ) of two different methyl groups in a molecule and of benzenegradually move upfield. The rate of upfield shifts of differently located methyl groups in a molecule differs from each other. The △δ of originally lowerfield methyl group is larger than that of originally upperfield methyl group, so the two resonance lines appear to overlap and cross over with the increment of the fraction of benzene in the mixed solvent. All of the chemical shifts can be related by a linear equation δ=A+BX, where, X is the mole fraction of benzene in the mixed solvent.

In this paper simulated proton spectrum and Homo-COSY,Hetero-CHCOR 2D NMR techniques were used to analyze and assign the ¹H and ¹³C NMR spectra of the Compound (E₄N)₂[Pd₂(mp)₂(μ-mph)₂].The results indicate that the Compound isstable in DMSO solution as their molecular structures remain the same as those in the solid state.

In this paper,we use the self-made ESI instrument to study the two dimensional density distribution of aromatic amine radicals on silica alumina surface with differentshapes.

3,3'-p-phenylene-bis(7-isopropoxy-coumarin) is a new compound used for fluorescent whitening agent.¹H NMR of this compound in CDCl₃ and DMSO-d₆ were measured, and the effects of solvent were studied.

In order to be sure of the specific chemical shift range for each hydrogen or carbon structural group,a database and managing system for NMR chemical shift of 725hydrocarbons published in Sadtler standard NMR spectra are established. With this database and managing system,statistical distribution charts of chemical shift for various hydrogen and carbon structural groups are given.NMR spectra of hydrocarbon,especially petroleum products can be analyzed with the above distribution charts.Thesystem can also be conveniently used to locate the standard spectrum.

This paper introduces the current status of LC coupled with NMR.The recent rapid advances in LC-NMR provides evidence that many of the major technical obstacles which was faced in the coupling of these two analytical techniques have been overcome.The use of coupled LC-NMR for the detection and identification of urinarymetabolites of ibuprofen is described.