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The determination of EG content in the liquid products of PET hydrolysis process under microwave irradiation at 170°C 180°C and 190°C was measured by Gas chromatography. The chromatographic column was quartz capillary chromatographic column the carrier gas was nitrogen hydrogen flame ionization detector FID. The result indicated that the concentration curves of EG didn’t follow a dynamic process which suggested that PET hydrolysis under microwave was not a continuous process dynamics.

Nylon 6/66 copolymer with 0-10wt% content of hexamethylene adipamide salt (AH-salt) was prepared by melt polycondensation. It was found that the comprehensive performance of the copolymer was the best with 8wt% content of AH-salt through the test of tensile properties and bibulous rate. Compared with the performance of nylon 6 under the same condition, the elongation at break was increased by 131.04% (the stretching rate was 30mm•min-1) to 274.41%, the tensile strength increased by 19.38% to 64.68MPa, and the bibulous rate was decreased by 8.58% to 2.14%.

The dynamic adsorption of Kr and Xe in activated charcoal were measured. The temperature dependence of breakthrough curves for individual isotopes of85mKr,87Kr,88Kr and135Xe have been determined from the γ-spectra at temperatures from 78 K to 291 K. The effective hold up and dynamic adsorption coefficient have been deduced. We find that adsorption is very sensitive to temperature and also depends on the size rather than on the mass of the adsorbed atom. Form total growth radioactivity, the time dependent brakthrough curves at the temperatures of 113, 195 and 220 K have been constructed. The curves were analyzed and compared with the model calculations. Fick's law describing the mass transfer of gas into porous solid was employed to obtain the adsorption coefficient from fitting the experimental data. The results show fairly good agreement between model predictions and the experiments.

A sensitive and selective high-performance liquid chromatographic method with electrochemical detection for the determination of gossypol in human plasma is described. Glutathione is used as a protective agent and gossypol dimethyl ether as an internal standard. Acetonitrile-treated protein-free plasma sample is first introduced on to a C18 pre-column for enrichment and clean-up. By using a column-switching technique, gossypol and the internal standard are subjected to further separation on a C8 analytical column, while the major interfering components are eliminated before entering the column. Methanol-0.1 M citrate buffer (pH 3.2) (80:20) is used as the mobile phase. The detector potential on the glassy carbon electrode is maintained at +0.6 V vs. an Ag-AgCl reference electrode. The linearity with human plasma ranged from 5 to 250 ng/ml. The absolute recoveries of gossypol and gossypol dimethyl ether were 91.3 and 97.5%, respectively, with a within-day precision of 2.5% and a day-to-day precision of 3.8%. The limit of detection is 5 ng/ml (signal-to-noise ratio = 3:1). The method is considered to be suitable for the clinical pharmacokinetic studies of gossypol.

Excitation functions and mean recoil ranges have been measured for radioactive products resulting from the helium-ion bombardment of natural zirconium and targets which were isotopically enriched in ${\mathrm{Zr}}^{90}$. Helium-ion energies varied between 25 and 80 MeV. Products observed were ${\mathrm{Mo}}^{90}$, ${\mathrm{Nb}}^{90}$, ${\mathrm{Zr}}^{89}$, ${\mathrm{Zr}}^{88}$, ${\mathrm{Y}}^{88}$, ${\mathrm{Zr}}^{87}$, ${\mathrm{Y}}^{87}$, ${\mathrm{Zr}}^{86}$, and ${\mathrm{Y}}^{86}$. The excitation function was also measured for the production of ${\mathrm{Y}}^{87}$. The recoil ranges are compared with the range theory of Lindhard, Scharff, and Schiott to determine the energy ranges over which the production of the nuclide is consistent with major contributions from a compound-nucleus mechanism. Excitation functions for products with $A\ensuremath{\ge}87$ were compared with the statistical model to investigate the influence of shell structure on level densities. The level-density models used were those due to Newton and to Rosenzweig in addition to the standard Fermi-gas level density. Rosenzweig's model gave the best over-all agreement with the experimental results, with the standard Fermi-gas level density a close second. Several excitation functions were calculated using the $s$-wave approximation to estimate the effect of $\ensuremath{\gamma}$-ray de-excitation due to angular-momentum restrictions. Threshold position and excitation-function widths were found to agree quite satisfactorily with experimental values when this was done.

Pharmacokinetic parameters of (+ or -)- (+)- and (-)-gossypol were determined in humans and dogs after a single oral or intravenous dose. Mean (+or- SD) oral bioavailability of (+or-)- gossypol in dogs was 30.9% +or- 16.2%. Studies in dogs who received single intravenous injections revealed that the elimination t 1/2 and volume of distribution of (=)-gossypol were 5 and 6 times those of (-)-gossypol respectively whereas total body clearance and the AUC of the 2 anantiomers were similar. Data from men receiving the compounds orally show that the average peak plasma concentration and the AUC of (+)- gossypol are significantly greater than those of the (-)-isomer. The rate constants of alpha beta ka k21 and k10 for (-)-gossypol are significantly greater than those for (+)-gossypol indicating higher rates of mass transfer of the (-)-species. In humans the elimination of t 1/2 of (+)-gossypol was 29 times as that of (-)-gossypol a difference that is more striking than that found in dogs. The elimination of t 1/2 of (+or-)-gossypol in humans averages 286 +or- 179 hours. (authors)

The independent isomeric yield ratio of146La and84Br in the thermal neutron fission of235U is reported for the first time with the values of 0.058±0.017 and 0.62±0.20, respectively. the yields have been determined using a fast radiochemical separation technique followed by γ-spectroscopy. The deduced rms angular momentum of84Br is 5.9 ℏ from the statistical model analysis and the rms angular momentum of146La is found too low to be determined.