A new pulse sequence for the measurement of NMR logging is proposed in this article, based on the improvement of original CPMG pulse sequence. In the original pulse sequence, after a CPMG pulse sequence, wait time (or T₁ relay) is needed to allow the magnetization vector return to equilibrium, then the next measuring CPMG pulse sequence can be applied. The wait time is kept long and the logging speed is low in formations that contain long T₁ components, since the logging apparatus is moving continuously along the bore hole. This is unfavorable because the spin-lattice relaxation time (T₁) of oil and gas is always long. However, it's noticed that if a 90° pulse from the-x direction (or a 270° pulse from the x direction) is applied after the former CMPG pulse sequence, the long T₁ components can be polarized more completely, then the wait time can be short-ened and logging speed c an be improved. The advantage of the improved pulse sequence is proved by calcul ations and analyses.

A novel heterocyclic diamine, 1,2-dihydro-2-(4-amino-phenyl)-4-[4-(4-amino-phenoxyl) phenyl](2H)phthalazin-1-one was synthesized. Its ¹H and ¹³C NMR spectra were completely assigned by utilizing the two-dimensional heteronuclear ¹³C-¹Hmultiple-bond coherence(HMBC) spectroscopy, and heteronuclear ¹³C-¹H one-bond coherence spectroscopy, homonuclear shift correlation spectroscopy(¹H,¹H-COSY) and the rotating frame overhauser enhancement spectroscopy(ROESY).The structure of the compound was proven to be phthalazinone instead of phthalazine ether.

The nuclear spin relaxation rate 1/T₁ of the laser-polarized ¹²⁹Xe produced in a low magnetic field was measured in a high magnetic field. The relations between the 1/T₁ and the pressure of N₂ or the temperature were obtained. The results show that the 1/T₁ increases as the pressure of N₂ varies from 0 to 11333.05Pa when the temperature was kept in 291K, and that the 1/T₁ decreases as the temperature varies from 234K to 292K when the pressure of N₂ was 1466.63Pa.

For the strong radiation damping case(i.e.,90%H₂O in D₂O), it has been found experimentally that when the initial angle of the magnetization relative to the B₀ direction, θ₀, is very close to π, the Fourier transformed spectra corresponding to the FIDs with hyperbolic envelope are characteristic of very strong oscillation, which is apparently different from that obtained with near-π pulse. This great oscillating feature can be reasonably explained in terms of the radiation damping lineshape theory.

The norfloxacin is an effective and safe anti-infective with broadspctrum, and can be taken orally. The interaction of norfloxacin with β-CD has been studied by several analytical techniques, including ¹H NMR, ¹³C NMR and fluorescence spectra. In this paper, inclusion complex of HP-β-CD with no rfloxacin were prepared based on the coprecipitation method. The characterization of the inclusion complex has been done by flu-orimetry, Irspectroscopy, differ ential scanning calorimetry, and 1D,2D NMR. H-5 of located in the interior of HP-β-CD cavity was observed considerably shifted upfeld, which provide some evidences for the interaction of norfloxacin and HP-β-CD. The experimental results confirmed the existence of a 1:1 inclusion complex of norfloxacin and HP-β-CD. The formation constant of the complex was determined by Fluorescence method, a modified Benesi Hildbrand procedure was employed to calculate the formation constant. A spacial configuration of the complex has been proposed based on these data.

In two dimensional experiments and relaxation measurements, some signals have very broadened line shape, which interferes the spectral analysis. It is demon strated in this paper, that the broadened signal can be filtered by CPMG pulse sequence and highly resolved NMR spectrum can be obtained.

The mid-chain peroxyl radicals trapped in the samples irradiated in air are less stable than the end-chain peroxyl radicals. It was indicated that thermal decays of the trapped radicals are second-order reactions. The compensation effects in kinetics exist between the apparent activation energy and the pre-exponent factor which effect reaction rate constants contrarily. Such phenomenon indicates that thermal decays of the trapped radicals are complex reactions which occur simultaneously at many active centres.

In this paper, we have designed computer program for calculated eigenvalues, eigenvectors of the energy matrices and fitted spectra, ZFS(Zero field splitting), EPR (Electron paramagnetic resonance) parameters of the Ni(M)₄X₂(M=pz、mpz,X=Cl、Br、I) compounds, by using complete configuration mixing unified crystal field theory. By this program, the spectra, ZFS,EPR parameters of the compound s Ni(M)₄X₂(M=pz、mpz,X=Cl、Br、I) are fitted with a single set of parameters. We have summarized general law that is fitted. All results consist with the experimental data.

With 1D ¹H NMR, ¹³C NMR and 2D ROESY NMR, the geometry of the procaine-β-cyclodextrin complex has been proposed and been proved.

Two-dimensional time evolution approach was applied to study corn germ and endosperm-water system. Measurements were made on; (1) germ without water (vacuum evaporation) but with different percentages of oil, (2) germ without oil(chemically extracted) but with different percentages of water and (3) endospermwater system with different percentages of water. Water interacts strongly with germ matrix and considerably decreases T₁ of the system, whereas oil almost remains independently with its surroundings. The behavior of low moisture (less then 5% of water) corngerm is the water bound to germ matrix and oil is in the form of oilcell. There are two T₁ components in germ matrix-water system. The exchange rates in long T₁ group is 57s^-1 from matrix to water and 113s^-1 from water to matrix. In short T₁ group, the exchange rate is 245s^-1 from matrix to water and 821s^-1 from water to matrix. At low hydration, the endosperm-water system has one T₁ component. The exchange rate from endosperm to water is higher than 37s^-1.

The calculation of molecular formula of compounds was described by ¹³C NMR (COM,DEPT) data in this paper. It is a useful method for unknown compounds.

The improvement of digital system of DNP spectrometer and establishment of a new system of transmission and receiver are introduced in this article. The π/2 pulse width is less than 5μs, which meets the requirement of CP and high power decoupling. The DNP enhancement curve can be obtained automatically.