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141.
Frontispiece: Proton Order–Disorder Phenomena in a Hydrogen‐Bonded Rhodium–η5‐Semiquinone Complex: A Possible Dielectric Response Mechanism 下载免费PDF全文
Dr. Minoru Mitsumi Kazunari Ezaki Yuuki Komatsu Prof. Dr. Koshiro Toriumi Dr. Tatsuya Miyatou Prof. Dr. Motohiro Mizuno Nobuaki Azuma Prof. Dr. Yuji Miyazaki Prof. Dr. Motohiro Nakano Prof. Dr. Yasutaka Kitagawa Dr. Takayasu Hanashima Dr. Ryoji Kiyanagi Dr. Takashi Ohhara Prof. Dr. Kazuhiro Nakasuji 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(27)
142.
Kitamura Noritaka Imai Nobuaki Haba Hiromitsu Michimasa Shin’ichiro Shimoura Susumu Yamaguchi Yuki 《Journal of Radioanalytical and Nuclear Chemistry》2021,330(3):721-725
Journal of Radioanalytical and Nuclear Chemistry - The nuclear isomer $$^{178}$$ Hfm2 enables various investigations owing to its unique properties. To study exotic nuclear reactions induced by... 相似文献
143.
Dr. Hiroshi Hinou Risho Miyoshi Yasuaki Takasu Hirokazu Kai Dr. Masaki Kurogochi Dr. Shingo Arioka Dr. Xiao‐Dong Gao Dr. Nobuaki Miura Dr. Naoki Fujitani Dr. Shinya Omoto Dr. Tomokazu Yoshinaga Dr. Tamio Fujiwara Dr. Takeshi Noshi Dr. Hiroko Togame Prof. Hiroshi Takemoto Prof. Shin‐Ichiro Nishimura 《化学:亚洲杂志》2011,6(4):1048-1056
A potent inhibitor for Vibrio cholerae neuraminidase (VCNA) was developed by using a novel two‐step strategy, a target amino acid validation using mechanism‐based labeling information, and a potent inhibitor search using a focused library. The labeling information suggested the hidden dynamics of a loop structure of VCNA, which can be a potential target of the novel inhibitor. A focused library composed of 187 compounds was prepared from a 9‐azide derivative of 2,3‐dehydro‐N‐acetylneuraminic acid (DANA) to interrupt the function of the loop of the labeled residues. Inhibitor 3c showed potent inhibition properties and was the strongest inhibitor with FANA, a N‐trifluoroacetyl derivative of DANA. Validation studies of the inhibitor with a detergent and a Lineweaver–Burk plot suggested that the 9‐substitution group would interact hydrophobically with the target loop moiety, adding a noncompetitive inhibition property to the DANA skeleton. This information enabled us to design compound 4 having the combined structure of 3c and FANA. Compound 4 showed the most potent inhibition (Ki=73 nM , mixed inhibition) of VCNA with high selectivity among the tested viral, bacterial, and mammal neuraminidases. 相似文献
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We have developed a space‐restricted wave function (SRW) method for the analysis of various types of intramolecular interactions. In this study, we demonstrate the applicability of our SRW method to the analysis of the nature of the P? O bond in phosphine oxide (R3PO), one of the hypervalent molecules. An interesting character of this bond has been extensively studied by focusing on the negative hyperconjugation of the O lone pair (nO) with the R3P group. We reinvestigated the nature of the bond in terms of a change in total energy to produce evidence for the validity of our method. The electronic states without the interaction involving three nO orbitals (R3P+?O?) produced by the method were used as reference states in the assessment of the effects of this nO–R3P interaction. The result confirms that this interaction plays an essential role in the nature of the bond and occurs between the nO orbitals and the P? R antibonding orbitals, in agreement with previous studies. A molecular orbital (MO)‐pair analysis technique shows that the nO–R3P interaction is decomposed into the negative hyperconjugation and the Pauli repulsion. Considering a reference state where the P? O bond is completely broken (R3P2+···O2?) at an interacting distance, P? O bond formation is attributed to one σ bond plus two 0.5 π bonds. This is equivalent to three banana bonds highly polarized to the O atom. Consequently, the SRW method suggested improved explanations of the nature of the P? O bond. © 2012 Wiley Periodicals, Inc. 相似文献
147.
Hyun-Ha Kim Masami Sugasawa Hiroshi Hirata Yoshiyuki Teramoto Katsunori Kosuge Nobuaki Negishi Atsushi Ogata 《Plasma Chemistry and Plasma Processing》2013,33(6):1083-1098
This paper presents a new type of ozone-assisted catalysis for toluene decomposition. The different catalytic activities of ZSM-5 and Ag/ZSM-5 were incorporated into a layered catalyst with a tandem configuration. Instead of increasing the amount of metal catalyst, the layered catalyst was formed, which had an equal amount of bare ZSM-5 and Ag/ZSM-5 and could achieve both high toluene conversion and CO2 selectivity concurrently. The properties of each catalyst were evaluated with respect to toluene conversion, formation of intermediates, CO2 selectivity and ozone demand factor. The bare ZSM-5 exhibited higher toluene conversion than the Ag/ZSM-5, while its activity toward deep oxidation was limited. However, the Ag/ZSM-5 was found to be effective for the deep oxidation of reaction intermediates (HCOOH and CO). Separate oxidation tests with HCOOH and CO revealed that the ZSM-5-supported Ag nanoparticles could oxidize the HCOOH and CO in the absence of ozone, which was not possible with the bare ZSM-5. Plausible pathways for the oxidation of toluene with O3 over ZSM-5 and Ag/ZSM-5 were proposed based on the experimental evidence. 相似文献
148.
Nobuaki Kambe Akira Nishiyama Shin-Ichi Fujiwara Tsutomu Shin-Ike Noboru Sonoda 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3-4):1001-1005
Abstract Lithium enolates of esters, amides, and an acylsilane undergo carbonylation with carbon monoxide with the aid of selenium under mild conditions to yield the corresponding selenol esters after trapping with alkyl iodides. 相似文献
149.
Ichikawa K Akamatsu T Shinke T Adulyanukosol K Arai N 《The Journal of the Acoustical Society of America》2011,129(6):3623-3629
Dugongs (Dugong dugon) produce bird-like calls such as chirps and trills. The vocal responses of dugongs to playbacks of several acoustic stimuli were investigated. Animals were exposed to four different playback stimuli: a recorded chirp from a wild dugong, a synthesized down-sweep sound, a synthesized constant-frequency sound, and silence. Wild dugongs vocalized more frequently after playback of broadcast chirps than that after constant-frequency sounds or silence. The down-sweep sound also elicited more vocal responses than did silence. No significant difference was found between the broadcast chirps and the down-sweep sound. The ratio of wild dugong chirps to all calls and the dominant frequencies of the wild dugong calls were significantly higher during playbacks of broadcast chirps, down-sweep sounds, and constant-frequency sounds than during those of silence. The source level and duration of dugong chirps increased significantly as signaling distance increased. No significant correlation was found between signaling distance and the source level of trills. These results show that dugongs vocalize to playbacks of frequency-modulated signals and suggest that the source level of dugong chirps may be manipulated to compensate for transmission loss between the source and receiver. This study provides the first behavioral observations revealing the function of dugong chirps. 相似文献
150.
Water-soluble l-cysteine capped Mn-doped ZnS@Si quantum-dots (QDs), a kind of sensitizer, were synthesized. It was found that this sensitizer could enhance chemiluminescence (CL) signals emitted from interaction of NaClO with H2O2 in basic medium. The CL mechanism was studied experimentally by singlet oxygen (1O2) quenching method, UV-vis spectra, X-ray photoelectron spectra, transmission electron microscopy studies and ESR spin-trapping spectra. The results demonstrated that the CL enhancement of NaClO-H2O2 originate from the catalysis of the sensitizer, which catalyzed the decomposition of H2O2, producing reactive intermediates hydroxyl radical (OH) and superoxide anion (O2−). Then the resulting OH reacted with O2− to form 1O2 and oxygen excimer species (1O2)2?, which rapidly returned to its ground state by passing its energy to the sensitizer through an electron-transfer process. Finally, the sensitizer being in excited state, returned to the ground state through enhanced CL-emission. 相似文献