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991.
992.
The kinetics of dissociation and racemization of [Fe(phen)3]2+ have been studied in aqueous methanol solutions containing perchlorate, chloride, and thiocyanate ions. The racemization rate was decreased by ClO?4 and increased by SCN?, while the dissociation rate was decreased by ClO?4 and increased slightly by Cl? and remarkably by SCN?. The effect of anions on the reaction rates became remarkable with the increase in methanol content of the solutions. The results were reasonably explained in terms of ion association. The dissociation rate of the complex ion in the ion-pair increased in the order, ClO?4 < Cl? < SCN?, of associated anions, suggesting the ion-pair interchange mechanism for the dissociation. The ion-association constants were determined to be 11 ± 4, 18 ± 4, and 25 ± 15 (I = 0.1, 25°C) for ClO?4, Cl?, and SCN?, respectively, in 0.64 mole-fraction (0.8 volume-fraction) aqueous methanol. 相似文献
993.
994.
995.
We determine the intermediate mass distribution of the dual resonance pomeron at the one-loop level and we show that the mass distribution obtained is remarkably similar to a suitably defined mass distribution in the dual multiperipheral model. Thus it is suggestive to identify the intermediate states of the dual resonance pomeron with multipheripheral processes. 相似文献
996.
Sayori Nakagawa Satoshi Fukumoto Naohiro Ishii 《Mathematical and Computer Modelling》2003,38(11-13):1357
This paper considers three checkpointing schemes which combine a double modular redundancy and three types of checkpoints: compare-and-store-checkpoint (CSCP), store-checkpoint (SCP), and compare-checkpoint (CCP). An execution time of a task is divided equally into n intervals, and at the end of each interval, a CSCP is always placed. Further, each CSCP interval is also divided equally into m intervals, and at the end of each interval, either CCP or SCP is placed except the last one. Introducing the overheads of comparison, storage, and retry, the mean execution times to complete a task for three schemes are obtained, using the theory of probability. Optimal checkpointing intervals, which minimize the mean times, are analytically derived, and are numerically computed. Three schemes are compared as numerical examples and the best checkpointing scheme is chosen. 相似文献
997.
Mitsuhiro Nakamura Masashi Mamino Shojiro Maki Satoshi Kojima Yoshihiro Ohmiya 《Tetrahedron letters》2005,46(1):53-56
A series of Latia luciferin analogues having methyl-substituted phenyl groups instead of the natural 2,6,6-trimethylhexene ring was synthesized and their bioluminescence activity were measured. The Latia luciferase was found to be able to moderately recognize the appropriately methyl-substituted phenyl analogues with the same light production kinetics as that of natural luciferin. 相似文献
998.
T. Fukui introduced an invariant for the blow-analytic equivalence of real singularities. For a nondegenerate analytic function (germ) f, he discovered a formula for computing the one-dimensional invariant, denoted by A(f) := A
1(f). We find a formula for A(f) for any f (real or complex, degenerate or not). We then define, and characterise, various notions of stability of A(f), using the formula. For real analytic f, the Fukui invariant with sign is defined, and computed by a similar formula. In the case where f is an analytic function of two complex variables, A(f) can also be computed using the tree-model of f. 相似文献
999.
Dibenzo[a,j]phenazine‐Cored Donor–Acceptor–Donor Compounds as Green‐to‐Red/NIR Thermally Activated Delayed Fluorescence Organic Light Emitters
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Dr. Przemyslaw Data Piotr Pander Masato Okazaki Prof. Dr. Youhei Takeda Prof. Dr. Satoshi Minakata Prof. Dr. Andrew P. Monkman 《Angewandte Chemie (International ed. in English)》2016,55(19):5739-5744
A new family of thermally activated delayed fluorescence (TADF) emitters based on U‐shaped D‐A‐D architecture with a novel accepting unit has been developed. All investigated compounds have small singlet‐triplet energy splitting (ΔEST) ranging from 0.02 to 0.20 eV and showed efficient TADF properties. The lowest triplet state of the acceptor unit plays the key role in the TADF mechanism. OLEDs fabricated with these TADF emitters achieved excellent efficiencies up to 16 % external quantum efficiency (EQE). 相似文献
1000.
Characterization of the Cytochrome c Membrane‐Binding Site Using Cardiolipin‐Containing Bicelles with NMR
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Hisashi Kobayashi Dr. Satoshi Nagao Prof. Dr. Shun Hirota 《Angewandte Chemie (International ed. in English)》2016,55(45):14019-14022
Cytochrome (cyt) c transports electrons from Complex III to Complex IV in mitochondria. Cyt c is ordinarily anchored to the mitochondrial membrane through interaction with cardiolipin (CL), however its release into the cytosol initiates apoptosis. The cyt c interaction site with CL‐containing bicelles was characterized by NMR spectroscopy. Chemical shift perturbations in cyt c signals upon interaction with bicelles revealed that a relatively wide region, which includes the A‐site, the CXXCH motif, and the N‐ and C‐terminal helices, and contains multiple Lys residues, interacts cooperatively with CL. The specific cyt c–CL interaction increased with increasing CL molecules in the bicelles. The location of the cyt c interaction site for CL was similar to those for Complex III and Complex IV, thus indicating that cyt c recognizes lipids and partner proteins in a similar way. In addition to elucidating the cyt c membrane‐binding site, these results provide insight into the dynamic aspect of cyt c interactions in mitochondria. 相似文献