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11.
Nicolas Zigon Manabu Hoshino Shota Yoshioka Yasuhide Inokuma Makoto Fujita 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2015,127(31):9161-9165
Crystal structures of α‐humulene, a cyclic sesquiterpene, and its oxidized subproducts, were analyzed by the crystalline sponge method. Regio‐ and stereochemistry, including absolute configuration when a chiral oxidant was applied, and the stable conformations of all the scaffold‐related compounds were successfully determined for samples on a 5–50 μg scale. 相似文献
12.
13.
Y. Fukumoto 《Theoretical and Computational Fluid Dynamics》2010,24(1-4):335-347
This article gives an overview of growing knowledge of translation speed of an axisymmetric vortex ring, with focus on the influence of viscosity. Helmholtz–Lamb’s method provides a shortcut to manipulate the translation speed at both small and large Reynolds number, for a vortex ring starting from an infinitely thin core. The resulting asymptotics significantly improve Saffman’s formula (1970) and give closer lower and upper bounds on translation speed in an early stage. At large Reynolds numbers, Kelvin–Benjamin’s kinematic variational principle achieves a further simplification. At small Reynolds numbers, the whole life of a vortex ring is available from the vorticity obeying the Stokes equations, which is closely fitted, over a long time, by Saffman’s second formula. 相似文献
14.
Yasuhide Shindo Fumio Narita Taiki Watanabe 《European Journal of Mechanics - A/Solids》2010,29(4):647-653
This paper examines the nonlinear electromechanical response of 1-3 piezoelectric/polymer composites. The piezocomposites contain square or circular piezoelectric rods in an epoxy matrix. Experiments were conducted to measure the displacement versus electric field curves, using the device specimen of the 1-3 piezocomposites. Three dimensional finite element analysis was also carried out to study the electromechanical fields in the 1-3 piezocomposites by introducing a model for polarization switching. Comparison was then made between simulation and experiment. 相似文献
15.
Prognosis of severe ischemic heart disease with no indication of percutaneous coronary intervention or coronary artery bypass
grafting still remains poor. Extracorporeal shock wave therapy was introduced for medical therapy more than 20 years ago to
break up kidney stones. We have demonstrated that extracorporeal cardiac shock wave therapy at a low level of ~10% of energy
density that used for urinary lithotripsy treatment, effectively induces coronary angiogenesis and improves myocardial ischemia
in a porcine model of chronic myocardial ischemia in vivo. On the basis of the promising results in animal studies, we have
recently developed a new, non-invasive angiogenic therapy with low-energy shock waves for ischemic heart disease. Our extracorporeal
cardiac shock wave therapy improved symptoms and myocardial ischemia in patients with severe coronary artery disease. These
beneficial effects of the shock wave therapy persisted for at least 12 months. Importantly, no procedural complications or
adverse effects were noted. These results indicate that our extracorporeal cardiac shock wave therapy is an effective and
non-invasive treatment for ischemic heart disease. To further confirm the usefulness and safety of our SW therapy, we are
currently conducting the second clinical trial in a randomized and placebo-controlled manner.
相似文献
16.
17.
Eiji Tsurumaki Yasuhide Inokuma Shanmugam Easwaramoorthi Dr. Jong Min Lim Dongho Kim Prof. Dr. Atsuhiro Osuka Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(1):237-247
Effective peripheral fabrication methods of meso‐aryl‐substituted subporphyrins were explored for the first time. Hexabrominated subporphyrins 2 were prepared quantitatively from the bromination of subporphyrins 1 with bromine. Hexaphenylated subporphyrins 3 and hexaethynylated subporphyrins 4 and 5 were synthesized by Suzuki–Miyaura coupling and Stille coupling, respectively, in good yields. X‐ray crystal structures of 2 b , 3 b , 4 b , and 5 a revealed preservation of the bowl‐shaped bent structures with bowl depths similar to that of 1 . Hexaethynylated subporphyrins exhibit large two‐photon‐absorption cross‐sections due to effective delocalization of the conjugated network to the ethynyl substituents. 相似文献
18.
Shanmugam Easwaramoorthi Dr. Jae‐Yoon Shin Sung Cho Dr. Pyosang Kim Yasuhide Inokuma Eiji Tsurumaki Atsuhiro Osuka Prof. Dr. Dongho Kim Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(44):12005-12017
Donor–acceptor systems based on subporphyrins with nitro and amino substituents at meta and para positions of the meso‐phenyl groups were synthesized and their photophysical properties have been systematically investigated. These molecules show two types of charge‐transfer interactions, that is, from center to periphery and periphery to center depending on the peripheral substitution, in which the subporphyrin moiety plays a dual role as both donor and acceptor. Based on the solvent‐polarity‐dependent photophysical properties, we have shown that the fluorescence emission of para isomers originates from the solvatochromic, dipolar, symmetry‐broken, and relaxed excited states, whereas the non‐solvatochromic fluorescence of meta isomers is of the octupolar type with false symmetry breaking. The restricted meso‐(4‐aminophenyl) rotation at low temperature prevents the intramolecular charge‐transfer (ICT)‐forming process. The two‐photon absorption (TPA) cross‐section values were determined by photoexcitation at 800 nm in nonpolar toluene and polar acetonitrile solvents to see the effect of ICT on the TPA processes. The large enhancement in the TPA cross‐section value of approximately 3200 GM (1 GM=10?50 cm4 s photon?1) with donor–acceptor substitution has been attributed to the octupolar effect and ICT interactions. A correlation was found between the electron‐donating/‐withdrawing abilities of the peripheral groups and the TPA cross‐section values, that is, p‐aminophenyl>m‐aminophenyl>nitrophenyl. The increased stability of octupolar ICT interactions in highly polar solvents enhances the TPA cross‐section value by a factor of approximately 2 and 4, respectively, for p‐amino‐ and m‐nitrophenyl‐substituted subporphyrins. On the other hand, the stabilization of the symmetry‐broken, dipolar ICT state gives rise to a negligible impact on the TPA processes. 相似文献
19.
Reactive acrylate esters were encapsulated in the cavity of networked molecular capsules in a single‐crystal‐to‐single‐crystal fashion. Owing to the encapsulation effect, acrylates inside the capsules do not undergo polymerization upon irradiation with UV light or heating, while the guest molecules can be quantitatively extracted by treatment with toluene. 相似文献
20.
We prove that the coinvariant ring of the irreducible Coxeter group of type H4 has the strong Lefschetz property. 相似文献