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101.
A general formalism of nonequilibrium thermodynamics of multicomponent fluids is given. Reversible parts of balance equations for the extensive variables are constructed in such a way that the growth rate of the extensive variables are related to their conjugate intensive parameters in an antisymmetric manner. This enables us to give the balance equation for the diffusional flow which plays an important role in the study of superfluidity and complex fluids. 相似文献
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A universal peroxyoxalate-chemiluminescence detection system for high performance liquid chromatography, available for a variety of mobile phases, has been developed. The system consisted of a dual-head short-stroke pump and a chemiluminescence detector. The standard conditions using bis(2,4,6-trichlorophenyl) oxalate (TCPO) as aryl oxalate were as follows. The first postcolumn solution was the mixture of 0.5 M imidazole-nitric acid (pH 7.5) and acetonitrile (1:4, v/v). The second was acetonitrile containing TCPO-hydrogen peroxide. These two solutions were delivered by the two pump-heads. After the pH of the column eluate was adjusted to the optimum range (6.5-7.5) by the first postcolumn solution, the solution was mixed with the second postcolumn solution. After flowing through a reaction coil, the chemiluminescence of the mixture was monitored. Using this system, a high sensitivity (fmol level) was obtained for perylene as an analyte with mobile phases having different pH values (2.0-8.0). Polycyclic aromatic hydrocarbons became detectable to a high sensitivity even after the column separation using an acidic mobile phase. The detection sensitivity of nitrated pyrenes after on-line electrochemical reduction using an acidic mobile phase was also increased. This system might be available for other aryl oxalates by some modifications of the postcolumn solutions. 相似文献
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Antitumor activity of shikonin and its derivatives 总被引:11,自引:0,他引:11
U Sankawa Y Ebizuka T Miyazaki Y Isomura H Otsuka 《Chemical & pharmaceutical bulletin》1977,25(9):2392-2395
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Omori Hideki Maeda Yoshiaki Miyazaki Naoya Yoshioka Akira 《Letters in Mathematical Physics》1998,46(2):171-180
It is well known that the Moyal bracket gives a unique deformation quantization of the canonical phase space R2n up to equivalence. In his presentation of an interesting deformation quantization of the Poisson algebra of Laurent polynomials, Ovsienko discusses the equivalences of deformation quantizations of these algebras. We show that under suitable conditions, deformation quantizations of this algebra are equivalent. Though Ovsienko showed that there exists a deformation quantization of the Poisson algebra of Laurent polynomials which is not equivalent to the Moyal product, this is not correct. We show this equivalence by two methods: a direct construction of the intertwiner via the star exponential and a more standard approach using Hochschild 2-cocycles. 相似文献