Samples of blood from adults in good health in Taiwan have been analyzed for their137Cs content by gross beta counting using a low background gas-flow counter. The level of137Cs content in blood was 8.3+6.3x10–3 pCi.ml–1 for ages 24+7 y. The deposition of fission product137Cs in Taiwan, which was monitored by water tray for fallout, was also studied since January 1979.
Authors:D. Lin, H. Wang, M. Lin, M. Lin, and Y. Wu
Adding a magnetic field gradient to the conventional TG system constructs the magnetic thermogravimetry analysis (TG(M) i.e. Faraday methods) and the magnetic derivative thermogravimetry (DTG(M)) techniques. We used the techniques to study the nanocrystalline processes of the FeCuNbSiB and FeCuNbCoSiB amorphous alloys. Some problems of their applications such as the characteristic temperature Tmin and TC are also discussed in detail.
Authors:D. Lin, M. Lin, M. Lin, Y. Wu, H. Wang, and Y. Chen
The —T and d/dT—T curves of the FeCuNbSiB amorphous alloy, which are the relationship between the total saturated magnetic moment per unit mass and temperature, are investigated by magnetic thermogravimetry analysis (TG(M)) technique. It is found that the crystallization process of the samples can be divided into five stages. The studies of samples annealed in temperature range of 480–610°C for 1h show that when the annealing temperature (Ta) is less than 540°C, the quantity of nanocrystalline -Fe(Si) phase increases evidently with Ta, and the Curie temperature (TC) of residual amorphous phase also increases linearly with Ta, i.e. TC=0.52Ta+91.7°C, with correlation coefficient =0.98. The variation of volume fraction of -Fe(Si) nanocrystalline phase or residual amorphous phase with Ta is measured by TG(M) technique.
Authors:C. Lin, Y. Chang, J. Lee, S. Lin, and C. Shu
Preventing accidental explosions of flammable liquid/gas mixtures is very important. As far as flammability characteristics
are concerned, we simulated the effects of inert liquid/gas, which was filled with reactors, vessels, or closed space, employed
in the chemical process industries. The inert liquid/gas (H2O) weakened the oxygen concentration and reduced solvent vapor concentration in a 20-L-Apparatus. This study investigated
the flammability characteristics of acetone/water solutions (100/0, 75/25, 50/50, and 25/75 vol.%) that are controlled at
a temperature of 150°C and pressures of 101/202 kPa, respectively. The flammability parameters included flammability limits
(LEL and UEL), maximum explosion pressure (Pmax), maximum explosion pressure rise ((dP dt−1)max), and vapor deflagration index (Kg). The results of a series of experimental tests showed that UEL, Pmax, and Kg all decreased with steam rising under the experimental conditions. The results can be applied to process safety design/operation
for identifying whether the inert liquid/gas (H2O) content has any substantial effects in reducing the fire and explosion hazard of the solution of interest.
Authors:S. Lin, J. Tseng, Y. Lin, W. Huang, and C. Shu
The polymerization mechanisms of styrene and various derivatives by α-methylstyrene (AMS) and trans-β-methylstyrene (TBMS) were evaluated. Experiments were carried out for dimerization identification and thermal polymerization
estimation by differential scanning calorimetry (DSC), thermal activity monitor (TAM) and Fourier transform infrared absorption
spectrophotometer (FTIR). The results show that, under temperature ranges of 60–190 and 50–170°C, AMS and TBMS performed dimerization
by benzene ring and ethylene double bond, respectively. AMS and TBMS would form unsaturated dimers, saturated dimers and trimers,
etc., during the period of thermal polymerization. Through this study, one can estimate possible intermediates of the polymerization
process for the monomer of interest in the petrochemical industry.
The thermal mechanical properties and degradation kinetics of Staybelite Resin, a thermoplastic, and its ester derivative Staybelite Ester 10 have been investigated using thermoanalytic methods. The thermogravimetric analyzer applied in the degradation studies has been interfaced with a minicomputer for data acquisition. The degradation kinetics of each thermosplastic have been satisfactorily attributed to an associated first-order process using a differential method.
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 -spectroscopy. The deduced rms angular momentum of84Br is 5.9 from the statistical model analysis and the rms angular momentum of146La is found too low to be determined.