All issues
Volume 19 (1992)
- Issue 4 Pages 151-
- Issue 3 Pages 103-
- Issue 2 Pages 57-
- Issue 1 Pages 2-
Volume 19, Issue 1
Displaying 1-6 of 6 articles from this issue
- |<
- <
- 1
- >
- >|
-
F. E. Karasz, P. Cifra1992 Volume 19 Issue 1 Pages 2-10
Published: January 30, 1992
Released on J-STAGE: September 07, 2009
JOURNAL FREE ACCESSInteractions play a decisive role in polymer-polymer miscibility. However, direct elucidation of interactions from thermodynamic mixing properties is experimentally cumbersome because of high viscosity and the glass transition temperature (Tg) effects in polymer systems, and because there are theoretical problems attributable to its mean-field approximation. Therefore we are interested in Monte Carlo (MC) simulations which overcome some of these restrictions and are an alternative to the experimental and theoretical approaches. Results of such simulations are available for only a few model systems. We present the results of three applications of the MC method to polymer blend systems.View full abstractDownload PDF (1510K) -
In Relation to a Mechanism of the Drug-induced HemolysisMagobei Yamamoto, Hatsumi Aki1992 Volume 19 Issue 1 Pages 11-19
Published: January 30, 1992
Released on J-STAGE: September 07, 2009
JOURNAL FREE ACCESSIonic drugs of chlorpromazine (CPZ), promethazine (PMZ), flufenamic acid (FA) and mefenamic acid (MA) were compared with each other as regards the hemolytic action, the thermodynamics of drug binding to human erythrocyte membrane and the uptake into the cell. (1) All the drugs binding interaction with human erythrocyte was spontaneous and exothermic as indicated by negative signs of free energy and enthalpy changes, and conversely the endothermic heat effect was found to be due to hemolysis and disruption of the membrane structure. (2) Cationic drugs, CPZ and PMZ, were bound and/or inserted to the inner erythrocyte membrane with a high affinity. The reactions were characterized by small negative enthalpy and large positive entropy changes which were contributed by hydrophobic interaction between drugs and the phospholipids in the membrane. While, the human erythrocyte had two kinds of binding sites on the cell membrane for anionic drugs, FA and MA; one strong binding site and other weak site with the lower affinity which were due to both ionic and hydrophobic interactions. About 15% of the bound drugs was penetrated into the intracellular membrane. The first class of the binding site was already saturated before hemolysis and the second class might play a significant role in hemolysis by the drugs. (3) As the results, a tentative mechanism for the ionic drug-induced hemolysis is proposed.View full abstractDownload PDF (1132K) -
Kazuyoshi Takeda, Kazuo Yamagata1992 Volume 19 Issue 1 Pages 20-31
Published: January 30, 1992
Released on J-STAGE: September 07, 2009
JOURNAL FREE ACCESSThermal and magnetic properties of two-dimensional spin systems have been summarized from the experimental point of view. The contents of this review article are
(1) The aim of the study of low-dimensional systems.
(2) Possibility of magnetic phase transition and heat capacity curve of two-dimensional lattices.
(3) Crossover phemomena induced by temperature and external magnetic field.
(4) Phase transition in magnetically diluted systems.
(5) Some remarks of frustrated systems.
The magnetic model systems treated in this article are mainly two-dimensional systems such as M(HCOO)2·2H2O and M(HCOO)2·2(NH2)2CO (M:Mn, Co), except a few one-dimensional compounds like (CH3)3NHCoCl3·2H2O and (NH3)4NMnCl3.View full abstractDownload PDF (1599K) -
Haruhiko Tanaka1992 Volume 19 Issue 1 Pages 32-39
Published: January 30, 1992
Released on J-STAGE: September 07, 2009
JOURNAL FREE ACCESSControlled transformation Rate Thermal Analysis (CRTA) as well as conventional thermoanalytical methods are reviewed in an attempt to get a wider comprehension of the kinetics of solid-state reactions. It is worthy of note that the apparent activation enegies E determined from the rate-jump method of CRTA are nearly constant irrespective of the sample size within a sample size range of 20∼200mg for the thermal decomposition of dolomite. On the other hand, some sample size dependence of E is inevitable with the conventional dynamic kinetic analyses unless the sample size is smaller than ca. 2mg. Errors inherent in such kinetic parameters determined for the solid-state reactions are considered in view of the feature characteristic of solid-state reactions as well as the assumption and prerequisite for the kinetic analyses. It is stressed, as for the conventional dynamic analyses, that isoconversion methods, e. g., the Flynn-Wall-Ozawa method, are useful in obtaining reliable Arrhenius parameters of the solidstate reactions in general. It is evident that isothermal analyses should also be made together with the conventional dynamic analyses with as smaller a sample size as possible.View full abstractDownload PDF (1103K) -
K. Takahashi, A. Asai, T. Takeuchi1992 Volume 19 Issue 1 Pages 40-42
Published: January 30, 1992
Released on J-STAGE: September 07, 2009
JOURNAL FREE ACCESSDownload PDF (313K) -
S. Shimada1992 Volume 19 Issue 1 Pages 43-45
Published: January 30, 1992
Released on J-STAGE: September 07, 2009
JOURNAL FREE ACCESSDownload PDF (376K)
- |<
- <
- 1
- >
- >|