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231.
Dr. Motoki Toganoh Hideaki Matsuo Ayumi Sato Prof. Hiroyuki Furuta 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(24):8316-8322
Ruthenocene‐type hybrid complexes with N‐fused porphyrinato ligands, [Ru(NFp)Cp] (NFp=N‐fused porphyrin, Cp=cyclopentadienyl), have been prepared and characterized by NMR and UV/Vis/NIR spectroscopy, cyclovoltammetry, and X‐ray crystallography. [Ru(NFp)Cp] is a common low‐spin ruthenium(II) complex and shows strong aromaticity. The Ru–Cp distance (1.833 Å) in [Ru(NFp)Cp] is comparable to that in [RuCp2] (1.840 Å). DFT calculations on [Ru(NFp)Cp] showed the unequivocal contribution of the RuCp moiety as well as the NFp moiety to both the HOMO and LUMO, constructing a three‐dimensional d–π conjugated system. The HOMO–LUMO gaps of [Ru(NFp)Cp] are insensitive to the substituents on the NFp ligand, which is illustrated spectroscopically as well as theoretically. This is in sharp contrast to the ligand precursor, the N‐fused porphyrin, in which the HOMO–LUMO gap is affected by substituents in a similar manner to standard porphyrins and related macrocycles. 相似文献
232.
Lithium‐Ion Endohedral Fullerene (Li+@C60) Dopants in Stable Perovskite Solar Cells Induce Instant Doping and Anti‐Oxidation 下载免费PDF全文
Dr. Il Jeon Dr. Hiroshi Ueno Seungju Seo Dr. Kerttu Aitola Ryosuke Nishikubo Prof. Akinori Saeki Dr. Hiroshi Okada Prof. Gerrit Boschloo Prof. Shigeo Maruyama Prof. Yutaka Matsuo 《Angewandte Chemie (International ed. in English)》2018,57(17):4607-4611
Herein, we report use of [Li+@C60]TFSI? as a dopant for spiro‐MeOTAD in lead halide perovskite solar cells. This approach gave an air stability nearly 10‐fold that of conventional devices using Li+TFSI?. Such high stability is attributed to the hydrophobic nature of [Li+@C60]TFSI? repelling moisture and absorbing intruding oxygen, thereby protecting the perovskite device from degradation. Furthermore, [Li+@C60]TFSI? could oxidize spiro‐MeOTAD without the need for oxygen. The encapsulated devices exhibited outstanding air stability for more than 1000 h while illuminated under ambient conditions. 相似文献
233.
A novel mediator-polymer-modified anode for microbial fuel cells 总被引:1,自引:0,他引:1
Adachi M Shimomura T Komatsu M Yakuwa H Miya A 《Chemical communications (Cambridge, England)》2008,(17):2055-2057
A high-performance anode system based on a combination of mediator-polymer-modified graphite felt and bacteria capable of reducing extracellular materials shows significant potential for practical use in microbial fuel cells (MFCs). 相似文献
234.
Higashihara G Inagaki A Akita M 《Dalton transactions (Cambridge, England : 2003)》2008,(14):1888-1898
A series of di- and trinucleating ligands with a 1,3,5-triethylbenzene core connected to N,N-bidentate tethers was synthesized. The ligands readily reacted with monuclear Rh and Pd precursors to give the corresponding di- and trinuclear complexes, which were characterized by using NMR and ESI mass spectroscopy. In the solid state, the trinuclear complexes with ligands having pyridylpyrazolyl tethers adopt the most stable ababab configuration, in which the organometallic fragments are on the same side of the benzene plane. On the other hand, in solution, the linker moieties between the benzene core and the metals are flexible enough to interconvert between other configurations, that is, they exhibit dynamic behavior, and the rotational barrier was dependent on the length of the linkers. From variable temperature (VT) 1H NMR measurements, the rotational barrier for a trinuclear Rh-CO complex with a ligand having methylene linkers was estimated to be approximately 12.6 kcal mol(-1). However, no spectral changes were observed for the ethylene derivative in the temperature range of -60 degrees C to 50 degrees C, indicating that the rotation was not frozen out on the 1H NMR timescale, even at -60 degrees C. 相似文献
235.
Akiko Tsuhako 《Tetrahedron letters》2008,49(46):6529-6532
Copper salts, such as CuCl, CuI, CuCl2 and Cu(OTf)2, were used to catalyze the intramolecular hydroamination of allenylamines to provide the corresponding 3-pyrrolines or 2-alkenylpyrrolidines. 相似文献
236.
M. Hirabayashi M. Matsuo S. Hasegawa S. Kobayashi K. Tanabe 《Journal of Radioanalytical and Nuclear Chemistry》2008,278(2):479-483
Airborne particulate matter was collected at the intersection of Industrial Road in Kawasaki-city, Kanagawa, Japan using a
12-stage low-pressure impactor. High concentrations of airborne particulate matter have been observed in this area. The collected
samples were analyzed for 34 elements by instrumental neutron activation analysis (INAA), and data on the elemental concentrations
were obtained. High concentrations of fine particles of As, Br, Sb, V, and Zn were observed. It was further observed that
these fine particles were originated predominantly from the wear of tires and brakes, and not from automobile exhaust emissions. 相似文献
237.
To raise the accuracy of the force field for nucleic acids, several parameters were elaborated, focusing on the rotation around chi torsion axis. The reliability of molecular dynamics (MD) simulation was significantly increased by improving the torsion parameters at C8--N9--C1'--X (X = H1', C2', O4') in A, G and those at C6--N1--C1'--X in C, T, and U. In this work, we constructed small models representing the chemical structure of A, G, C, T, and U, and estimated energy profile for chi-axis rotation by executing numerous quantum mechanical (QM) calculations. The parameters were derived by discrete Fourier transformation of the calculated QM data. A comparison in energy profile between molecular mechanical (MM) calculation and QM one shows that our presently derived parameters well reproduce the energy surface of QM calculation for all the above torsion terms. Furthermore, our parameters show a good performance in MD simulations of some nucleic acids. Hence, the present refinement of parameters will enable us to perform more accurate simulations for various types of nucleic acids. 相似文献
238.
Reductive amination reaction using 7-amino-4-methylcoumarin (AMC) as a fluorescent probe enabled analyses of glycoproteins' monosaccharides and N-linked oligosaccharides. Reductive amination of N-acetylhexosamines and AMC using sodium cyanoborohydride or dimethylamine-borane complex indicated slight recovery of derivatives, but pyridine-borane achieved better recoveries. Reversed-phase high-performance liquid chromatography (HPLC) analyses of monosaccharides constituting glycoprotein glycans using fluorimetric detection revealed linearity for 0.2fmol to 1pmol, with less than 5% RSD quantitation reproducibility. Reversed-phase HPLC analyses of glycoprotein glycans, combined with negative-ion electrospray ionization mass spectrometry (LC-ESI-MS), enabled their structural determination. Using this highly hydrophobic reagent, AMC-labeled oligosaccharides displayed one-order to two-order higher ESI-MS intensity than derivatives labeled using other reagents. 相似文献
239.
240.
Tanaka A Matsuo Y Hashimoto Y Ijiro K 《Chemical communications (Cambridge, England)》2008,(36):4270-4272
Platinum metal was sequence-specifically deposited on the DNA block copolymer synthesized by the Klenow fragment of E. coli DNA polymerase I (3'-5' exonuclease deficient). 相似文献