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31.
Masamura Shinnosuke Iwamoto Tetsu Sugitani Yoshiki Konishi Keiji Hara Naoyuki 《Nonlinear dynamics》2020,99(4):3155-3168
Nonlinear Dynamics - The present study experimentally investigates amplitude death in delay-coupled double-scroll circuits with a time-varying network topology that randomly changes at a regular... 相似文献
32.
S. A. E. Boyer J-P. E. Grolier L. Pison C. Iwamoto H. Yoshida T. Iyoda 《Journal of Thermal Analysis and Calorimetry》2006,85(3):699-706
The
present work deals with the interactions between carbon dioxide, used as pressure
medium, either in the gas state (GCO2) or in the supercritical
state (SCCO2) and amphiphilic di-block copolymers PEOm-b-PMA(Az)n. The effect of
pressure on the isotropic transition of the PEOm-b-PMA(Az)n copolymer was investigated
using scanning transitiometry (ST). The experimental results were compared
with those measured when using ‘relatively inert’ mercury (Hg)
as pressure medium. Morphological observation of a PEOm-b-PMA(Az)n thin film submitted
to SCCO2 was performed by atomic force microscopy (AFM)
to investigate the nano-structure organization. These results indicate the
possibility of modifying the nano-structure in a specific way depending on
the CO2 physical state. 相似文献
33.
34.
pharaonis phoborhodopsin (ppR, also called pharaonis sensory rhodopsin II [psRII]) is a member of the archaeal rhodopsin family and acts as a repellent phototaxis receptor of Natronobacterium pharaonis. Upon illumination, ppR is excited and undergoes a linear cyclic photoreaction, namely, a photocycle that constitutes photointermediates such as M- and O-intermediates (ppRM and ppRO, respectively). Under a constant background illumination (>600 nm) that irradiates ppRO, the decay rate of the flash-induced ppRO increased with an increase in the background light intensity, indicating the photoreactivity of ppRO. Azide did not influence the light-accelerated ppRO decay, but the time required for the cycle to be completed became shortened in an azide concentration-dependent manner because of acceleration of ppRM decay. Hence, the turnover rate of photocycling increased appreciably in the presence of both the background illumination and the azide. The observation reported previously (Schmies, G. et al. 2000, Biophys. J. 78:967-976) is discussed in connection with the present observations. 相似文献
35.
The carbonylation of a phenyllithium containing an oxazoline group at the ortho position, followed by quenching with water, afforded a tricyclic compound, 3,3-dimethyl-2,3-dihydrooxazolo[2, 3-a]isoindol-5(9bH)-one, in 91% yield. This reaction proceeded via an intramolecular cyclization of the aroyllithium species, to give the tricyclic dienolate. Treatment of the tricyclic dienolate with electrophiles, such as alkyl halides, aldehydes, ketones, and epoxides gave the substituted oxazolo[2,3-a]isoindolinones in good yield. 相似文献
36.
The temperature dependence of the mass parameter is analyzed starting from the Inglis cranking formula. At temperatures higher than the critical temperature corresponding to a vanishing pairing gap, the mass parameter is found to approach that of the incompressible liquid drop value, at least qualitatively. This general result is tested for several simple cases where we can get almost analytical results. In these cases clear relations between the cranking mass and the incompressible liquid drop value are obtained. 相似文献
37.
Construction of eight-membered carbocyclic rings via the intramolecular B-alkyl Suzuki-Miyaura cross-coupling reaction has been studied. This protocol proved its potency through the formation of the eight-membered ring possessing a quaternary carbon on its ring in high yield, affording promise of a new access to the eight-membered ring of Taxol. [reaction: see text] 相似文献
38.
Eguchi K Enomoto S Furuno K Goldman J Hanada H Ikeda H Ikeda K Inoue K Ishihara K Itoh W Iwamoto T Kawaguchi T Kawashima T Kinoshita H Kishimoto Y Koga M Koseki Y Maeda T Mitsui T Motoki M Nakajima K Nakajima M Nakajima T Ogawa H Owada K Sakabe T Shimizu I Shirai J Suekane F Suzuki A Tada K Tajima O Takayama T Tamae K Watanabe H Busenitz J Djurcic Z McKinny K Mei DM Piepke A Yakushev E Berger BE Chan YD Decowski MP Dwyer DA Freedman SJ Fu Y Fujikawa BK Heeger KM Lesko KT Luk KB Murayama H 《Physical review letters》2003,90(2):021802
KamLAND has measured the flux of nu;(e)'s from distant nuclear reactors. We find fewer nu;(e) events than expected from standard assumptions about nu;(e) propagation at the 99.95% C.L. In a 162 ton.yr exposure the ratio of the observed inverse beta-decay events to the expected number without nu;(e) disappearance is 0.611+/-0.085(stat)+/-0.041(syst) for nu;(e) energies >3.4 MeV. In the context of two-flavor neutrino oscillations with CPT invariance, all solutions to the solar neutrino problem except for the "large mixing angle" region are excluded. 相似文献
39.
Yutaka Nishigaichi Ken-ichi Tamura Narifumi Ueda Hidetoshi Iwamoto Akio Takuwa 《Tetrahedron letters》2008,49(13):2124-2127
Using a single allyltin reagent with a chiral nitrogen functionality, binary and remote asymmetric induction was realized toward various aldehydes. Either syn- or anti-1,4-amino-alcohols were selectively obtained with the use of Yb(OTf)3 or SnCl4, respectively. The structures of both diastereomers were identified by means of X-ray analysis. 相似文献
40.
Abstract— The photoinduction of petite colonies and cell toxicity in non-growing yeast, Saccharomyces cerevisiae , by 3-a-zido-6-a-mino-10-m-ethylacridinium chloride (AAMAC) has been examined. The results presented here indicate that mitochondrial DNA damage in resting yeast which occurs following irradiation of AAMAC-treated cells for short time periods is probably mediated through a covalent adduct between AAMAC and DNA. Furthermore, the photoreaction which contributes to biological activity is dependent on the presence of oxygen. Pre-irradiated AAMAC, which no longer exhibited the short-term photo-induction of biological effects showed a second biological activity. In this case longer irradiation times, e.g. 30 min, were required to induce petites for resting yeast. Again there was a strong dependence on the presence of oxygen. These results suggest that both processes may be effected through oxygen intermediates (photodynamic processes). 相似文献