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  • Author or Editor: L. Lin x
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Abstract  

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.

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Tocopherols, tocotrienols and γ-oryzanol are potent antioxidants of rice grains, and they may play an important role in the germination and growth of rice plants. In this study, the objective was to examine the effects of germination time on contents of Toc, T3, GO and ascorbate, as well as enzymatic antioxidant activities in the grains of two different rice varieties, namely TN71 and KS139. Samplings were conducted at 0, 3, 6 and 9 days after imbibition. The results showed that T3 and GO contents, but not Toc increased during seedling emergence. Toc content showed a trend of decrease from 0 DAI to 6 DAI. Contrasting to KS139, the AsA content in the grains of TN71 increased with increasing DAI. KS139 showed a time-dependent increase in the dehydroascorbate level, while that of TN71 remains unchanged at all times. TN71 showed significant increases in superoxide dismutase, catalase, ascorbate peroxidase and glutathione reductase activities in the late germination stages (9 DAI); with the exception of APX, KS139 exhibited a relatively constant enzymatic activities throughout the germination period. The changes in the malondialdehyde and H2O2 levels were minimum before 6 DAI, however a significant increase was noted at 9 DAI. This study indicates that besides the enzymatic antioxidants, the increase in T3 and GO contents may play a role in countering the oxidative stress during rice grain germination.

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This article indicates another set-theoretic formula, solely in terms of union and intersection, for the set of the limits of any given sequence (net, in general) in an arbitrary T 1 space; this representation in particular gives a new characterization of a T 1 space.

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Abstract  

Carburization and coke deposition of unsupported and carbon-supported Fe, Mo and Fe−Mo catalysts in syngas have been studied using thermogravimetry. Compositions of the carbides formed are evaluated on the basis of the amount of metals in the catalysts and amount of carbon deposited during carburization. It is shown that carburization temperature and the nature of the carbides formed (Fe5C2 and Fe2C for iron and Mo2C for molybdenum) depend on the metals but are influenced by the support and metal loading. Coke deposition on these catalysts takes place as soon as carburization is complete.

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Abstract  

The catalytic performance of unsupported and carbon-supported Fe, Mo and Fe−Mo catalysts for Fischer-Tropsch synthesis is greatly influenced by the final reduction states of the catalysts. In this investigation, the reduction process of the catalysts by H2 was studied by using TG-DTG. The reduction process depends not only on the reducibility of metals but also on the nature of the support. Methanation of the support occurred as soon as the supported metals were completely reduced for the carbon-supported catalysts. For these, the reduction temperature should by carefully selected so that the metal oxides are reduced as completely as possible, whilst the methanation of the support must be avoided to obtain optimum reduced catalysts.

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Abstract  

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.

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Abstract  

Soybean oil based polyols (5-OH polyol, 10-OH polyol and 15-OH polyol) were synthetised from epoxidized soybean oil. The melting peak of polyols and the relationship between melting peak and the number-average functionality of hydroxyl in polyols were investigated by differential scanning calorimetry (DSC). The thermal decomposition of polyols and some of their thermal properties by thermogravimetry (TG) and derivative thermogravimetry (DTG) were also studied. The thermal stability of polyols in a nitrogen atmosphere was very close hence they had a same baseplate of triglyceride for polyols. The extrapolated onset temperature of polyols in their thermal mass loss, first step had a decreasing order: 5-OH polyol>10-OH polyol>15-OH polyol due to the difficulty in forming multiple elements ring of them had the same order. The thermal behavior of polyols under non-isothermal conditions using Friedman’s differential isoconversional method with different heating rates indicated that the 5-OH polyol had the lowest activation energy in thermal decomposition amongst these polyols according to the same fractional mass loss because of the weakest intramolecular oligomerization. The 15-OH polyol was prior to reach the mass loss region because the six-member ring is more stable than the three-member ring from 10-OH polyol and more easily formed.

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