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711.
The synthesis of thromboxane A2 (TXA) analogue, 9α,11α-thia-TXA2 methyl ester 2, in which the oxygen atom in the oxetane ring of TXA2 was replaced by a sulfur atom, is described.  相似文献   
712.
A synthesis of nitrogen containing thromboxane, A2 analog, dl-(9,11)-methano-(11,12)-amino thromboxane A2 (1) is described.  相似文献   
713.
Concentrations of butyltin compounds (BTs) were determined in harbour porpoise (Phocoena phocoena) collected from the Turkish coastal waters of the Black Sea. Total butyltin compounds (∑ BTs) in the liver were in the range of 89–219 ng/g on a wet weight basis. The dibutyltin (DBT) residues were higher than those of tributyltin (TBT), suggesting the degradation of TBT to DBT in the liver and the metabolic capacity comparable to other marine mammals. Any sex difference and age-dependent accumulation of BTs residues were not found in harbour porpoises, but residue levels increased until maturity and then remained constant. When compared with other marine mammals, the present results indicate that the Black Sea is also contaminated with butyltin compounds, but to a lesser degree than coastal waters of developed nations. The biomagnification factor in harbour porpoises was 0.8, which was comparable with pinnipeds and lower than cetaceans. Received: 23 December 1996 / Revised: 15 April 1997 / Accepted: 16 April 1997  相似文献   
714.
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716.
A mixing experiment of multicomponents melts was performed using a uniform temperature furnace in the Second International Microgravity Laboratories (IML-2) mission. Growth morphologies and Ga concentration profiles were analyzed for the samples with the compositional ratio of 0.5 In–0.5 Ga–1.0 Sb grown under microgravity and on earth. The sample with free surface grown under microgravity was nearly spherical in shape, except some parts with projections. Ga was dispersed homogeneously in the bulk because the mixing was enhanced by Marangoni convection due to the concentration gradient. On the other hand, the sample grown on earth was a double cylindrical shape with different diameters, and Ga concentration decreased from top to bottom, showing clearly the effect of gravity. Many needle crystals were formed in both space and earth samples due to rapid cooling. The average size of the needle crystals grown in space was larger than that of the earth sample.  相似文献   
717.
We consider an inverse problem of determining unknown coefficients for a one-dimensional analogue of radiative transport equation. We show that some combination of the unknown coefficients can be uniquely determined by giving pulse-like inputs at the boundary and observing the corresponding outputs. Our result can be applied for determination of absorption and scattering properties of an optically turbid medium if the radiative transport equation is appropriate for describing the propagation of light in the medium.  相似文献   
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