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141.
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
142.
Takafumi Osuga Takashi Murase Manabu Hoshino Makoto Fujita 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2014,126(42):11368-11371
A tray‐shaped PdII3AuI3 complex ( 1 ) is prepared from 3,5‐bis(3‐pyridyl)pyrazole by means of tricyclization with AuI followed by PdII clipping. Tray 1 is an efficient scaffold for the modular assembly of [3×n] AuI clusters. Treatment of 1 with the AuI3 tricyclic guest 2 in H2O/CH3CN (7:3) or H2O results in the selective formation of a [3×2] cluster ( 1 ⋅ 2 ) or a [3×3] cluster ( 1 ⋅ 2 ⋅ 1 ), respectively. Upon subsequent addition of AgI ions, these complexes are converted to an unprecedented Au3–Au3–Ag–Au3–Au3 metal ion cluster. 相似文献
143.
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
144.
Brian N. DiMarco Dmitry E. Polyansky David C. Grills Ping Wang Yutaka Kuwahara Xuan Zhao Etsuko Fujita 《Chemphyschem》2021,22(14):1478-1487
In this work, the differences in catalytic performance for a series of Co hydrogen evolution catalysts with different pentadentate polypyridyl ligands (L), have been rationalized by examining elementary steps of the catalytic cycle using a combination of electrochemical and transient pulse radiolysis (PR) studies in aqueous solution. Solvolysis of the [CoII−Cl]+ species results in the formation of [CoII(κ4-L)(OH2)]2+. Further reduction produces [CoI(κ4-L)(OH2)]+, which undergoes a rate-limiting structural rearrangement to [CoI(κ5-L)]+ before being protonated to form [CoIII−H]2+. The rate of [CoIII−H]2+ formation is similar for all complexes in the series. Using E1/2 values of various Co species and pKa values of [CoIII−H]2+ estimated from PR experiments, we found that while the protonation of [CoIII−H]2+ is unfavorable, [CoII−H]+ reacts with protons to produce H2. The catalytic activity for H2 evolution tracks the hydricity of the [CoII−H]+ intermediate. 相似文献
145.
Byelikov A Adachi T Fujita H Fujita K Fujita Y Hatanaka K Heger A Kalmykov Y Kawase K Langanke K Martínez-Pinedo G Nakanishi K von Neumann-Cosel P Neveling R Richter A Sakamoto N Sakemi Y Shevchenko A Shimbara Y Shimizu Y Smit FD Tameshige Y Tamii A Woosley SE Yosoi M 《Physical review letters》2007,98(8):082501
The Gamow-Teller strength distributions below the particle threshold in 138La and 180Ta, deduced from high-resolution measurements of the (3He,t) reaction at 0 degrees, allow us to evaluate the role of charged-current reactions for the production of these extremely rare nuclides in neutrino-nucleosynthesis models. The analysis suggests that essentially all 138La in the Universe can be made that way. Neutrino nucleosynthesis also contributes significantly to the abundance of 180Ta but the magnitude depends on the unknown branching ratio for population of the long-lived isomer. 相似文献
146.
Surface neural activity has been widely visualized using optical intrinsic signal imaging (OISI) from various cortical sensory areas. OISI of the cortical surface with a CCD camera gives integrated information across a depth of a few hundred micrometers. We visualize depth-resolved activation patterns of cat primary visual cortex by functional optical coherence tomography (fOCT). A comparison of the depth-integrated results of fOCT maps with the optical intrinsic signal profiles shows fairly good agreement. Our results reveal layer-specific activation patterns and indicate that the activation was not homogeneous. 相似文献
147.
148.
Yoshida Keiichiro Ishizuka Tomohiro Mizushima Chiharu Nishidate Izumi Kawauchi Satoko Sato Shunichi Sato Manabu 《Optical Review》2015,22(2):374-384
Optical Review - To evaluate multi-spectral images of the absorption and scattering properties in the cerebral cortex of rat brain, we investigated spectral reflectance images estimated by the... 相似文献
149.
Manabu Yamada Muniyappan Rajiv Gandhi Yoshihiko Kondo Fumio Hamada 《Supramolecular chemistry》2014,26(7-8):620-630
The ability of chloroform solutions of p-diethylaminomethylthiacalix[4]arene 1 to extract platinum from HCl media was tested. As an ion-pair extractant, compound 1 had the highest platinum extraction ability among all the thiacalix[n]arene derivatives tested in this study. Compound 1 was a highly specific extractant for Pt(IV) ions from single-metal solutions and platinum-group metal solutions from automotive catalyst residue. Various conditions such as contact time, pH, concentration of 1, effect of chloride ions, effect of acidity and Pt(IV) concentration were studied. The distribution ratio of platinum ions (D) was calculated. The platinum complex stoichiometry ratio was obtained using slope analysis. The 1–Pt(IV) complex was characterised using X-ray photoelectron spectroscopy, FT-IR and 1H NMR. Finally, the Pt(IV) extraction percentage of compound 1 was compared with that of previously reported thiacalix[n]arene-based extractants. 相似文献
150.
Dual Catalysis with Copper and Rhenium for Trifluoromethylation of Propargylic Alcohols: Efficient Synthesis of α‐Trifluoromethylated Enones
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Dr. Hiromichi Egami Takafumi Ide Masashi Fujita Toshifumi Tojo Prof.Dr. Yoshitaka Hamashima Prof.Dr. Mikiko Sodeoka 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(38):12061-12065
Trifluoromethylation of propargylic alcohols to provide (Z)‐α‐trifluoromethylated enones and β‐unsubstituted α‐trifluoromethylated enones proceeded with high yield and selectivity in the presence of CuI/Re2O7. The Z isomer was formed under kinetic control, though it is less stable than the E isomer in terms of steric repulsion. 相似文献