[1] We have made observations of a heat signature that is associated with the frictional heat generated at the time of faulting for a large earthquake. Temperature measurements in a borehole that intersects the Chelungpu fault at a depth of about 1100 m, show a small increase near the fault even six years after the earthquake. The temperature signature has a symmetric shape with a width of about 40 m and is centered on the fault that slipped about 5 m during the 1999 Chi-Chi, Taiwan earthquake. The small amplitude of 0.06°C for the observed temperature anomaly indicates a very low level of friction that generated heat at the time of the earthquake.

By introducing a small amount (0.15 part by weight) of sulfur into EPDM/DVB/DCPO compounds, Young's modulus and the rupture energy of the vulcanizates are markedly increased. The swelling equilibrium and dynamic mechanical behaviour show that an increase in crosslinking is achieved by the addition of sulfur. Moreover, electron microscopic study has revealed that vulcanizates from sulfur containing compounds have a better state of dispersion of the resinous poly-DVB phase than those without sulfur. When the amount of sulfur is too great (>0.20 part), Young's modulus of the vulcanizate is markedly reduced, mainly because of insufficient polymerization of DVB. Sulfur apparently acts as a retarder of DVB polymerization. Furthermore, it is proposed that some reaction products of peroxide and sulfur could be the initiator of this polymerization.

Stereoregular polymerizations of some vinyl ketones were examined by using several Methyl vinyl ketone was found to be polymerized by some catalysts such as calcium zinc tetraethyl and phenylmagnesium bromide (etherate) to give highly crystalline polymers which melt a t about 160 "C. and can easily form spherulites.Moreover, methyl vinyl ketone, unlike other vinyl compounds, was also polymerized to form crystalline polymers by use of triethylaluminum, diethylzinc and diethylcadmium as catalysts without any added co-catalyst. The polymerization of methyl vinyl ketone with these metal alkyl catalysts was found to be anionic in nature from a series of copolymerization experiments.Phenyl vinyl ketone and methyl isopropenyl ketone were also polymerized by the same organometallic catalysts. Poly-(phenyl vinyl ketone) obtained did not exhibit much higher crystallinity compared with the conventional polymer, whereas some specimens of poly-(methyl isopropenyl ketone) prepared by the "at"-complexes or diethylzinc as catalyst were highly crystalline. anionic catalysts. ZUSAMMENFASSUNG:Die stereoregulke Polymerisation einiger Vinylketone wurde unter Verwendung verschiedener anionischer Katalysatoren untersucht.Methylvinylketon polymerisiert mit einigen dieser Katalysatoren, z. B. Calcium-Zink-Tetraathyl und Phenylmagnesiumbromid (hitherat) zu hochkristallinen Polymeren, die bei etwa 160 "C schmelzen und leicht Sphkolithe bilden.Dariiber hinaus bildet Methylvinylketon, im Gegensatz zu anderen Vinylverbindungen, auch mit Triathylaluminium, Diathylzink und Diathylcadmium kristalline Polymere, und zwar schon ohne besonders zugesetzte Cokatalysatoren. Aus Copolymerisationsversuchen wird geschlossen, da13 die Polymerisation des Methylvinylketons mit diesen Alkylkatalysatoren eine anionische ist.Phenylvinylketon und Methylisopropenylketon wurden mit den gleichen organometallischen Katalysatoren polymerisiert. Das Polyphenylvinylketon zeigte, im Vergleich zum bisher bekannten Polymeren, keine erhohte Kristallinitat, wogegen Proben voo Polymethylisopropenylketon, die mit Hilfe der "at"-Komplexe oder mit Diathylzink gewonnen wurden, hochkristallin waren.

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