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排序方式: 共有1335条查询结果,搜索用时 31 毫秒
1.
Maroni Fabio Bruni Pantaleone Suzuki Naoki Aihara Yuichi Croce Fausto 《Journal of Solid State Electrochemistry》2019,23(6):1697-1703
Journal of Solid State Electrochemistry - All-solid-state batteries represent the next generation of electrochemical energy storage systems. A tin-carbon nanocomposite material is prepared by the... 相似文献
2.
Enhancement of Light Absorption Ability of Synthetic Chlorophyll Derivatives by Conjugation with a Difluoroboron Diketonate Group 下载免费PDF全文
Dr. Yusuke Kinoshita Dr. Yuichi Kitagawa Prof. Dr. Hitoshi Tamiaki 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(29):9996-10001
The enhancement of the light absorption ability of synthetic chlorophyll derivatives is demonstrated. Chlorophyll derivatives directly conjugated with a difluoroboron 1,3‐diketonate group at the C3 position were synthesized from methyl pyropheophorbide‐d through Barbier acylmethylation of the C3‐formyl moiety, oxidation of the C3‐carbinol, and difluoroboron complexation of the diketonate. Electronic absorption spectra in a diluted solution showed that the synthetic conjugates gave an absorption band at λ=400–500 nm, with a Qy band shifted to a longer wavelength of λ≈700 nm. DFT calculations demonstrated that the absorption bands and redshifts were ascribable to the coupling of the LUMO of chlorin with that of the difluoroboron diketonate moiety. The introduction of a pyrenyl group at the C33‐position of the conjugate afforded an additional charge‐transfer band over λ=500 nm, producing a pigment that bridged the green gap in standard chlorophylls. 相似文献
3.
Inside Cover: Enhancement of Light Absorption Ability of Synthetic Chlorophyll Derivatives by Conjugation with a Difluoroboron Diketonate Group (Chem. Eur. J. 29/2016) 下载免费PDF全文
4.
Noboru Sato Yuichi Funato Yasuyuki Fukushima Takeshi Momose Mitsuo Koshi Yukihiro Shimogaki 《国际化学动力学杂志》2020,52(6):359-367
We established a gas-phase, elementary reaction model for chemical vapor deposition of silicon carbide from methyltrichlorosilane (MTS) and H2, based on the model developed at Iowa State University (ISU). The ISU model did not reproduce our experimental results, decomposition behavior of MTS in the gas phase in an environment with H2. Therefore, we made several modifications to the ISU model. Of the reactions included in existing models, 236 were lacking in the ISU model, and thus were added to the model. In addition, we modified the rate constants of the unimolecular reactions and the recombination reactions, which were treated as a high-pressure limit in the ISU model, into pressure-dependent rate expressions based on the previous reports (to yield the ISU+ model), for example, H2(+M) → H + H(+M), but decomposition behavior remained poorly reproducible. To incorporate the pressure dependencies of unimolecular decomposition rate constants, and to increase the accuracies of these constants, we recalculated the rate constants of five unimolecular decomposition reactions of MTS using the Rice-Ramsperger-Kassel-Marcus method at the CBS-QB3 level. These chemistries were added to the ISU+ model to yield the UT2014 model. The UT2014 model reproduced overall MTS decomposition. From the results of our model, we confirmed that MTS mainly decomposes into CH3 and SiCl3 at the temperature around 1000°C as reported in the several studies. 相似文献
5.
6.
Total Synthesis and Biological Evaluation of the Antibiotic Lysocin E and Its Enantiomeric,Epimeric, and N‐Demethylated Analogues 下载免费PDF全文
Dr. Motoki Murai Takuya Kaji Dr. Takefumi Kuranaga Dr. Hiroshi Hamamoto Prof. Dr. Kazuhisa Sekimizu Prof. Dr. Masayuki Inoue 《Angewandte Chemie (International ed. in English)》2015,54(5):1556-1560
Lysocin E, a macrocyclic peptide, exhibits potent antibacterial activity against methicillin‐resistant Staphylococcus aureus (MRSA) through a novel mechanism. The first total synthesis of lysocin E was achieved by applying a full solid‐phase strategy. The developed approach also provides rapid access to the enantiomeric, epimeric, and N‐demethylated analogues of lysocin E. Significantly, the antibacterial activity of the unnatural enantiomer was comparable to that of the natural isomer, suggesting the absence of chiral recognition in its mode of action. 相似文献
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8.
Cross-benzoin condensation catalyzed by NHC, prepared from chiral triazolium salts bearing a pyridine ring, afforded α-hydroxy ketones with reasonable chemical yields and enantioselectivities. A wide range of aliphatic and aromatic aldehydes were successfully used in the reaction. 相似文献
9.
Takano Yuichi Ishii Nobuaki Muraki Masaaki 《Central European Journal of Operations Research》2017,25(2):303-323
Central European Journal of Operations Research - In competitive bidding for project contracts, contractors estimate the cost of completing a project and then determine the bid price. Accordingly,... 相似文献
10.
Jinhua Hong Shunsuke Kobayashi Akihide Kuwabara Yumi H. Ikuhara Yasuyuki Fujiwara Yuichi Ikuhara 《Molecules (Basel, Switzerland)》2021,26(12)
Solid electrolytes, such as perovskite Li3xLa2/1−xTiO3, LixLa(1−x)/3NbO3 and garnet Li7La3Zr2O12 ceramic oxides, have attracted extensive attention in lithium-ion battery research due to their good chemical stability and the improvability of their ionic conductivity with great potential in solid electrolyte battery applications. These solid oxides eliminate safety issues and cycling instability, which are common challenges in the current commercial lithium-ion batteries based on organic liquid electrolytes. However, in practical applications, structural disorders such as point defects and grain boundaries play a dominating role in the ionic transport of these solid electrolytes, where defect engineering to tailor or improve the ionic conductive property is still seldom reported. Here, we demonstrate a defect engineering approach to alter the ionic conductive channels in LixLa(1−x)/3NbO3 (x = 0.1~0.13) electrolytes based on the rearrangements of La sites through a quenching process. The changes in the occupancy and interstitial defects of La ions lead to anisotropic modulation of ionic conductivity with the increase in quenching temperatures. Our trial in this work on the defect engineering of quenched electrolytes will offer opportunities to optimize ionic conductivity and benefit the solid electrolyte battery applications. 相似文献