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排序方式: 共有472条查询结果,搜索用时 20 毫秒
1.
Katoh Katsumi Fukui Satomi Haba Ayane Higashi Eiko Saburi Tei Okada Ken 《Journal of Thermal Analysis and Calorimetry》2022,147(13):7563-7571
Journal of Thermal Analysis and Calorimetry - Nitrocellulose (NC) is prone to spontaneous decomposition with exothermic heat release and thus is generally evaluated for stability during the storage... 相似文献
2.
Masaki Kato Dr. Norihito Fukui Prof. Dr. Hiroshi Shinokubo 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(2):e202103647
We report the synthesis and properties of indeno[1,2,3,4-pqra]perylene, which was prepared by the fusion of one anthracene unit with one naphthalene unit via three carbon-carbon bonds. The synthetic route through two-fold C−H arylation enabled not only the synthesis of unsubstituted indenoperylene, but also rapid access to its arylated derivatives on the gram scale. Indenoperylene is a medium-sized aromatic hydrocarbon with the composition C24H12 that is isomeric to coronene. Nevertheless, its absorption covers the entire visible region owing to its small HOMO-LUMO gap. Furthermore, indenoperylene exhibits high stability despite the absence of peripheral substituents. We propose that the unique electronic structure of indenoperylene originates from the coexistence of an electron-withdrawing subunit (benzoaceanthrylene) and an electron-donating subunit (perylene). The electronic properties of indenoperylene were modulated via post-functionalization through regioselective bromination. The current research demonstrates that indenoperylene is a promising candidate as a main skeleton for near-infrared-responsive and redox-active materials. 相似文献
3.
4.
Norihito Fukui Prof. Dr. Hideki Yorimitsu Prof. Dr. Atsuhiro Osuka 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(51):18476-18483
A meso–meso‐linked diphenylamine‐fused porphyrin dimer and its methoxy‐substituted analogue were synthesized from a meso–meso‐linked porphyrin dimer by a reaction sequence involving Ir‐catalyzed β‐selective borylation, iodination, meso‐chlorination, and SNAr reactions with diarylamines followed by electron‐transfer‐mediated intramolecular double C?H/C?I coupling. While these dimers commonly display characteristic split Soret bands and small oxidation potentials, they produced different products upon oxidation with tris(4‐bromophenyl)aminium hexachloroantimonate. Namely, the diphenylamine‐fused porphyrin dimer was converted into a dicationic closed‐shell quinonoidal dimer, while the methoxy‐substituted dimer gave a meso–meso, β‐β doubly linked porphyrin dimer. 相似文献
5.
Yong Li Xia Wen Lei Li Feng Wang Ning Zhao Fukui Xiao Wei Wei Yuhan Sun 《Journal of Sol-Gel Science and Technology》2013,66(3):353-362
A one-pot template-free route was developed for the synthesis of novel tetraethylenepentamine modified porous silica as CO2 adsorbents, the obtained materials were characterized by N2 adsorption/desorption, thermogravimetry, elemental analysis, Fourier transform infrared spectrometry,scanning electron microscopy and transmission electron microscopy. It was found that the amine species were inserted into the silica skeleton, which considerably enhanced their dispersion. Compared with similar materials derived from impregnation, the porous structure of the silica can be better reserved, leading to a promising CO2 adsorption capacity of 3.98 mmol CO2/g-adsorbent and a fast adsorption kinetic in simulated flue gas at 348 K. The resulted adsorbents could also be easily regenerated and showed a good durability in multiple adsorption–desorption cycles. All these features make this method a promising option for the preparation of CO2 adsorbents. 相似文献
6.
Prof. Dr. Mutsumi Kimura Junya Masuo Yuki Tohata Kazumichi Obuchi Naruhiko Masaki Takurou N. Murakami Nagatoshi Koumura Kojiro Hara Atsushi Fukui Ryohsuke Yamanaka Prof. Dr. Shogo Mori 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(3):1028-1034
A series of panchromatic ruthenium sensitizers ( MJ sensitizers) with attached thiophene and phenyl units bearing alkyl chains was synthesized. A new synthetic route was used to examine all possible positions for the alkyl chains. The absorption spectra showed the sum of a ruthenium complex and peripheral organic chromophore units. The hypochromic effect and blueshift of the metal‐to‐ligand charge‐transfer band observed in the modified ruthenium sensitizers were suppressed by changing the positions of the alkyl chains on the attached thiophene ring. Changing only one alkyl chain also influenced the performance of dye‐sensitized solar cells. Ruthenium sensitizer MJ‐10 with bulky substituent harvests visible and near‐infrared light, and solar cells sensitized by MJ‐10 exhibit an efficiency of 9.1 % under 1 sun irradiation. 相似文献
7.
Munetaka Iwamura Airi Fukui Koichi Nozaki Hikaru Kuramochi Satoshi Takeuchi Tahei Tahara 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(51):23354-23361
Femtosecond time-resolved absorption and picosecond time-resolved emission measurements were carried out for highly concentrated aqueous solutions of K2[Pt(CN)4] to investigate excited-state dynamics of the [Pt(CN)42−] oligomers formed with metallophilic interactions. Time-resolved absorption spectra exhibit complicated dynamics that are represented with five time constants. Among them, the 90-ps and 400-ps dynamics were assigned to the S1 → T1 intersystem crossing of the trimer and tetramer coexisting in the solution by comparison with the fluorescence decays. Clear oscillations of transient absorption were observed in the first few picoseconds, and the frequency-detected-wavelength 2D analysis revealed that the 135-cm−1 and 65-cm−1 oscillations arise from the Pt–Pt stretch motions of the S1 trimer and S1 tetramer, respectively. The obtained time-resolved spectroscopic data provide a clear view of the excited-state dynamics of the [Pt(CN)42−] oligomers in the femto-/picosecond time region. 相似文献
8.
K. Yamaguchi M. Fujii T. Inoue M. Haraguchi T. Okamoto M. Fukui 《Applied Physics A: Materials Science & Processing》2011,103(3):721-724
A planar bilayered silver prisms with rounded corner is shown to have a singular optical mode depends of gaps by numerical
simulation. Such behavior results from the plasmon resonance in the pairs of nanoprisms both the electric and the magnetic
components of light. 相似文献
9.
Enantioselective Total Synthesis of Dysidavarone A,a Novel Sesquiterpenoid Quinone from the Marine Sponge Dysidea avara 下载免费PDF全文
Yurie Fukui Koichi Narita Prof. Dr. Tadashi Katoh 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(9):2436-2439
Dysidavarone A, a structurally unprecedented sesquiterpenoid quinone, was synthesized in 30 % overall yield in a longest liner sequence of 13 steps from commercially available o‐vanillin. A highly strained and bridged eight‐membered carbocyclic core was established by the C7?C21 carbon bond formation through a copper enolate mediated Michael addition to the internal quinone ring. 相似文献