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351.
Kobayashi T Shiga M Murakami A Nakamura S 《Journal of the American Chemical Society》2007,129(20):6405-6424
Phenol blue (PB) is a primary skeletal structure part of indoaniline dyes and well-known as a solvatochromic dye. It has been recently observed by pump-probe (PP) transient absorption measurements that PB shows ultrafast ground state recovery within a few hundred femtoseconds after photoexcitation. In this work, the ultrafast photochemical reaction mechanism of PB has been investigated using direct ab initio (CASSCF) nonadiabatic molecular dynamics with the trajectory surface hopping (TSH) method. The swarm of trajectories starting from the S1 Franck-Condon (FC) point has mostly shown surface hops (nonadiabatic transitions) from the S1 state to the S0 state at 110-120 fs in the vicinity of an S1/S0 conical intersection and after decay to the S0 state bifurcated into two (Reverse and Forward) directions with almost the same branching ratio and reached the vicinity of the S0 minimum energy point at 200-300 fs, which is in good agreement with the fast time component of the ground state recovery in the PP measurements. After reaching the vicinity of the S0 minimum energy point, the trajectories showed a coherent vibration of bending motion between quinoneimine and aniline rings with a low frequency of 43 cm-1, which presumably corresponds to a coherently photoexcitation-induced vibrational mode with a low frequency recently observed by the PP measurements. 相似文献
352.
Akinori Furuya Ai-ichiro Sasaki Hiroki Morimura Osamu Kagami Mitsuru Shinagawa 《Optical Review》2014,21(5):605-613
In this paper, we describe how to obtain a low cost electrooptic (EO) sensor module for the mass production of near-field intrabody communication devices. In our previous study, we used a bulk cleavage technique to fabricate EO modulators without the need for any optical polishing or washing processes. In this study, we fabricated EO modulators as a miniaturized chip sensor without a base portion, and clarified the feasibility of assembling optical components by only a passive alignment technique with a compact housing. 相似文献
353.
The cyclopropanation of ethyl 3-trimethylsiloxy-2-alkenoates with the Simmons-Smith reagent, followed by ring cleavage and hydrolysis with an alkali solution, gave the corresponding 3-methyl-4-oxoalkanoic acids and 5-oxoalkanoic acids. 相似文献
354.
355.
A series of experiments dealing with the reduction of cinnamaldehyde and parent compounds was carried out in completely aqueous media in order to assess the character of this process. We wish to show that the treatment of these substrates in water with Raney catalysts is an oxido-reductive process. 相似文献
356.
Akane Yamakawa Akinori Takeuchi Yasuyuki Shibata Sylvain Berail Olivier François Xavier Donard 《Accreditation and quality assurance》2016,21(3):197-202
Hg isotopic ratios of NIES CRM No. 13 Human Hair were analyzed using cold vapor generation coupled to multi-collector inductively coupled plasma mass spectrometer to meet the growing demand for better understanding of Hg exposure routes by using Hg isotopic compositions in human hair samples. To validate and assure the accuracy of our analytical method, (1) the reproducibility of the Hg isotopic measurement was monitored and (2) the Hg isotopic compositions of four secondary reference materials—IAEA-085, IAEA-086, and CRPG-RL24H—were measured. Our results for NIES CRM No. 13 show the mass-dependent fractionation values of δ 199Hg = (2.13 ± 0.07) ‰, δ 200Hg = (0.98 ± 0.08) ‰, δ 201Hg = (2.77 ± 0.10) ‰, δ 202Hg = (1.89 ± 0.10) ‰, and δ 204Hg = (2.76 ± 0.16) ‰ (2SD, n = 11) and the mass-independent fractionation values of Δ 199Hg = (1.65 ± 0.06) ‰, Δ 200Hg = (0.04 ± 0.04) ‰, Δ 201Hg = (1.36 ± 0.07) ‰, and Δ 204Hg = (?0.04 ± 0.11) ‰ (2SD, n = 11). Interlaboratory comparison of the CRM performed at the University of Pau showed good agreement with the values obtained at NIES. 相似文献
357.
Kenichi Hatanaka Junji Oishi Akinori Tsuda Sae Matsunaga Megumi Kunou Yoshihide Yachi Maria Carmelita Kasuya Tatsuyuki Okinaga 《Macromolecular bioscience》2001,1(9):397-400
A hydrophobic 96‐well multiplate was incubated with aqueous poly(uridine 5′‐p‐styrenesulfonate) (PUSS). Analysis of the PUSS‐coated surface indicated that the surface incubated at higher polymer concentration (50 mg·mL–1) was hydrophilic while the surface incubated at lower polymer concentration (1 mg·mL–1) was hydrophobic. Adhesion of 3T3‐L1, which has GalTase on the cell membrane, on the hydrophobic PUSS‐coated surface was greater than on the non‐coated surface. 3T3‐L1 adhesion on the hydrophilic PUSS‐coated surface was even greater. On the other hand, the adhesion of HeLa cells, which did not show GalTase on the cell membrane, on the hydrophilic surface was quite weak. It may well be said that the 3T3‐L1 adhesion on the hydrophilic PUSS‐coated surface was GalTase‐mediated. 相似文献
358.
A Spin‐Active,Electrochromic, Solvent‐Free Molecular Liquid Based on Double‐Decker Lutetium Phthalocyanine Bearing Long Branched Alkyl Chains 下载免费PDF全文
Agnieszka Zielinska Dr. Atsuro Takai Dr. Hiroya Sakurai Dr. Akinori Saeki Dr. Marcin Leonowicz Dr. Takashi Nakanishi 《化学:亚洲杂志》2018,13(7):770-774
Synthesis and characterization of a novel, multifunctional, solvent‐free room‐temperature liquid based on alkylated double‐decker lutetium(III) phthalocyanine (Pc2Lu) are described. Lowering of the melting point and viscosity of intrinsically solid Pc2Lu compounds has been achieved through the attachment of flexible, bulky, and long branched‐alkyl chains, that is, thio‐2‐octyldodecyl, to the periphery of the Pc2Lu unit. The embedded Pc2Lu unit maintains its inherent molecular functions, such as spin‐active nature and electrochromic behavior in the liquid state. Comparison of the properties with a solid‐like Pc2Lu derivative, functionalized with shorter alkyl chains, that is, thio‐2‐ethylhexyl, underlines the importance of the hampering effect on the π–π interactions of neighboring Pc2Lu molecules by bulkier and longer branched‐alkyl chains. This study could possibly pave the way for novel multifunctional liquids whose spin‐activities are associated with their rheological or optoelectronic properties. 相似文献
359.
Yamagami R Kobayashi K Saeki A Seki S Tagawa S 《Journal of the American Chemical Society》2006,128(7):2212-2213
We report the first direct observation of charge transport dynamics using time-resolved microwave conductivity and transient absorption spectroscopy techniques on the photolysis of an anthraquinone-bound DNA complex. 相似文献
360.
Fratiloiu S Grozema FC Koizumi Y Seki S Saeki A Tagawa S Dudek SP Siebbeles LD 《The journal of physical chemistry. B》2006,110(12):5984-5993
The electronic structure and optical properties of charged oligofluorenes were studied experimentally and theoretically. Measurements of the optical absorption spectra of charged oligofluorenes in dilute solutions have been performed by using the pulse radiolysis technique. In addition, optical absorption spectra of radical cations and anions in a solid matrix were measured after gamma-irradiation at 77 K. The optical absorption spectra were measured in the range of 440-2100 nm (0.6-2.8 eV) and compared with results from time-dependent density functional theory (TDDFT) calculations. The calculated charge induced deformations and charge distribution do not indicate the occurrence of polaronic effects. The potential energy profiles for rotation around the inter-unit bond show that oligofluorenes are nonplanar in their neutral state, while they tend to more planar structures in their charged state. The optical absorption spectra of charged oligofluorenes are dependent on the angle between neighboring units. TDDFT absorption energies shift to lower values with increasing chain length, which suggests that the charge delocalizes along the oligomer chain. 相似文献