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91.
Soukil Mah Yukio Yamamoto Koichiro Hayashi 《Journal of polymer science. Part A, Polymer chemistry》1982,20(7):1709-1716
Radiation-induced cationic polymerization of styrene was studied in methylene chloride in the presence of triphenylsulfonium hexafluorophosphate. Acceleration in polymerization and an increase in molecular weight at a low temperature (?78°C) were observed in the presence of triphenylsulfonium salt. A study of pulse radiolysis revealed that both effects are due mainly to PF?6, which forms ion pairs with the cationic species involved in the polymerization. 相似文献
92.
The concept of MTF is introduced to analyze and describe consistently the hologram copying process, considering the original hologram as a volume hologram. The effect of the copying condition on the quality of the replica is expressed quantitatively in terms of the MTF. It turns out that holograms can be copied most successfully when the copying beam is oriented parallel to the original reference beam. The theoretical prediction is experimentally confirmed. 相似文献
93.
94.
The reaction of silyldibromomethyllithium with aromatic imines provides alpha-amino acylsilanes via a bromo aziridine intermediate upon quenching the reaction with water. Alternatively, treatment of the bromo aziridine intermediate with various Grignard reagents or lithium aluminum hydride permits the nucleophilic displacement of the halogen to furnish substituted silyl aziridines. 相似文献
95.
Wititsuwaannakul D Rattanapittayaporn A Koyama T Wititsuwaannakul R 《Macromolecular bioscience》2004,4(3):314-323
Centrifugation of fresh Hevea rubber latex yields three distinct fractions. The sediment bottom fraction (BF) content of membrane-bound organelles is ca. 20 vol.-% of latex. Prolonged storage or delayed use of fresh latex will result in disintegration and loss of the bottom fraction. This is due to the osmotically sensitive BF rupture and its membrane debris being tightly bound to the top rubber particles (RP) phase. The BF membrane was found to be highly active for rubber biosynthesis (RB), in contrast to previous reports that describe RB only occurring on the RP surface. It was clearly shown that washed BF membrane (WBM) was much more active than fresh RP for RB activity. WBM was highly activated by SDS for RB in a biphasic manner, but SDS strongly inhibited the RP. Probably WBM micelle formation resulted in a highly increased active surface area for RB. C55-PP (UPP) was a very active allylic for WBM in RB function, but inactive for RP. Serial acetone extraction of WBM proteins showed a distinct profile of the fractions with different RB activity. WBM isolated proteins suspended in 2% sodium dodecyl sulfate (SDS) with an RB activity equal to that of intact WBM was with the 20% acetone protein fraction. The 60 and 80% fractions were inactive. Combining the 20 with 80% fractions showed a complete inhibition of RB activity. Complete RB loss was also found when WBM was mixed with the 80% fraction, indicating that WBM has both an enzyme system and a factor for regulation of the RB activity in a well controlled metabolic function for the latex RB process. 相似文献
96.
Koyama E Ishida T Tokuhisa H Belaissaoui A Nagawa Y Kanesato M 《Chemical communications (Cambridge, England)》2004,(14):1626-1627
The protonation/deprotonation response of a novel bipyridine containing (phenylene-ethynylene) thiol adsorbed to a Au surface was investigated with scanning tunneling microscopy (STM), showing reversible changes in the average heights (approximately 50 spots) and the height distribution arising from protonation/deprotonation. 相似文献
97.
Fujii T Naito A Yamaguchi S Wada A Funahashi Y Jitsukawa K Nagatomo S Kitagawa T Masuda H 《Chemical communications (Cambridge, England)》2003,(21):2700-2701
A novel hydroperoxo-copper(II) complex with a square-planar geometry has been prepared, which has exhibited a higher selectivity and catalytic reactivity for dimethyl sulfide, in contrast to that with a trigonal-bipyramidal one. 相似文献
98.
99.
[reaction: see text] Treatment of allenes with tetraallylmanganate provides allylated products with high regioselectivity. A catalytic amount of MnCl(2) combined with allylmagnesium chloride also achieves efficient allylmetalation of allenes. The resulting alkenylmagnesium species react with various electrophiles. In the presence of molecular oxygen, the alkenylmagnesium undergoes diallylation reaction. A cyclization reaction of 1,2,6-heptatriene with tetraallylmanganate is also described. 相似文献
100.
Musubu Ichikawa Nobuyasu Hiramatsu Norimasa Yokoyama Tetsuzo Miki Susumu Narita Toshiki Koyama Yoshio Taniguchi 《固体物理学:研究快报》2007,1(1):R37-R39
We demonstrate that a bipyridyl substituted oxadiazole (Bpy‐OXD) shows high electron mobility that reached above 10–3 cm2/Vs. We believe that the high mobility results from both the hybrid molecular structure of the two electron‐accepting units: bipyridyl and oxadiazole, and the planar molecular structure based on its lack of sterically hindered bulky substituent. The computational analysis elucidates that the amorphous nature of Bpy‐OXD in thin‐film state probably results from the polymorphic effect in isolated state and the volume effect in solid state. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献