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191.
Harada Y Takeuchi T Kino H Fukushima A Takakura K Hieda K Nakao A Shin S Fukuyama H 《The journal of physical chemistry. A》2006,110(49):13227-13231
The electronic structures of a series of DNA nucleobases and their dinucleotides were investigated by N 1s X-ray absorption, X-ray photoemission, and resonant X-ray emission spectroscopy. Resonant X-ray emission spectra of the guanine base and its dinucleotide indicate that it has a weak structure at the lowest binding energy; at this energy, it isolates from the main valence band and forms the HOMO state. This indicates that the HOMO state is localized in the guanine base, as claimed by valence and core photoemissions and expected from theoretical predictions. In addition, the XAS and XES profiles of the guanine dinucleotide indicate that disruption of the aromatic character of the six-membered ring results in the localization of the pi state at the imine (-N=) site of the guanine base; this may favor charge transfer among stacked guanine bases and further influence the conductivity of DNA. 相似文献
192.
Motoyanagi J Fukushima T Ishii N Aida T 《Journal of the American Chemical Society》2006,128(13):4220-4221
A coumarin-appended amphiphilic hexa-peri-hexabenzocoronene (1) self-assembled to form graphitic nanotubes. Upon irradiation of lambda > 300 nm, the nanotubes in the solid state and suspension both underwent dimerization of the coumarin pendants, affording covalently stitched nanotubes, which were hardly soluble in CHCl3, a good solvent of 1. In contrast, a thin film cast from a homogeneous solution of 1 was intact to photoirradiation. Owing to the reversible nature of the photochemical stitching, both negative and positive patterns of the graphitic nanotubes were developed on a silicon substrate by a lithographic post processing. 相似文献
193.
Yoshida H Fukushima H Ohshita J Kunai A 《Journal of the American Chemical Society》2006,128(34):11040-11041
A zwitterion, generated from an aryne and an imine, has been demonstrated to serve as an excellent molecular scaffold for capturing CO2, which results in the straightforward formation of diverse benzoxazinones. 相似文献
194.
Imamura K Sakaura K Ohyama K Fukushima A Imanaka H Sakiyama T Nakanishi K 《The journal of physical chemistry. B》2006,110(31):15094-15099
Temperature scanning Fourier transform infrared, TS-FTIR, spectroscopy of various amorphous sugar matrixes was conducted to investigate the relationship between the glass transition temperature, T(g), of an amorphous sugar matrix and the nature of the hydrogen bonds in the matrix. An amorphous sugar matrix was prepared by air-drying an aqueous solution of sugar, and the degree of formation of hydrogen bonds in the matrix was evaluated at different temperatures using the peak positions of the IR band corresponding to the O-H stretching vibration at around 3400 cm(-1). The T(g) value increased with increasing peak position of the O-H stretching vibration at T(g) and were correlated reasonably well with the magnitude of the peak shift by the temperature increase (from 25 degrees C) to the T(g) value. This demonstrates that the amorphous sugar matrix, in which the segments are fixed by fewer hydrogen bonds, has a higher thermal resistance. The glycosidic linkage largely contributes to the restriction of the segments, pyranose ring, rather than a hydrogen bond. As the degree of polymerization of pyranose rings increases, the degree of hydrogen bond formation needed to hold the matrix in a fixed position decreases. However, the magnitude of the restriction of pyranose rings by a glycosidic linkage changes depending on the type: the restrictions imposed by alpha-1,1 and -1,6 glycosidic linkages are the tightest and most flexible of all of the types of glycosidic linkages, respectively. 相似文献
195.
A high-power 532 nm-pumped multikilohertz nanosecond optical parametric oscillator using a periodically poled 1.0 mol.% MgO-doped stoichiometric lithium tantalate crystal that could be operated from room temperature to 200 degrees C without damage is reported. A broad continuous tuning range from 855 to 1410 nm was achieved within a single domain period. Efficient operation of high peak power and watt level average power with a power conversion of 62.5% was measured. These results show that a high-resolution high average power visible tunable source can be realized. 相似文献
196.
Dashan Huang Shushang Zhu Frank J. Fabozzi Masao Fukushima 《European Journal of Operational Research》2010
Robust optimization, one of the most popular topics in the field of optimization and control since the late 1990s, deals with an optimization problem involving uncertain parameters. In this paper, we consider the relative robust conditional value-at-risk portfolio selection problem where the underlying probability distribution of portfolio return is only known to belong to a certain set. Our approach not only takes into account the worst-case scenarios of the uncertain distribution, but also pays attention to the best possible decision with respect to each realization of the distribution. We also illustrate how to construct a robust portfolio with multiple experts (priors) by solving a sequence of linear programs or a second-order cone program. 相似文献
197.
Wei‐Shi Li Prof. Dr. Akinori Saeki Dr. Yohei Yamamoto Dr. Takanori Fukushima Dr. Shu Seki Prof. Dr. Noriyuki Ishii Dr. Kenichi Kato Dr. Masaki Takata Prof. Dr. Takuzo Aida Prof. Dr. 《化学:亚洲杂志》2010,5(7):1566-1572
To tailor organic p/n heterojunctions with molecular‐level precision, a rational design strategy using side‐chain incompatibility of a covalently connected donor–acceptor (D–A) dyad has been successfully carried out. An oligothiophene–perylenediimide dyad, when modified with triethylene glycol side chains at one terminus and dodecyl side chains at the other ( 2 Amphi ), self‐assembles into nanofibers with a long‐range D/A heterojunction. In contrast, when the dyad is modified with dodecyl side chains at both termini ( 2 Lipo ), ill‐defined microfibers result. In steady‐state measurements using microgap electrodes, a cast film of the nanofiber of 2 Amphi displays far better photoconducting properties than that of the microfiber of 2 Lipo . Flash‐photolysis time‐resolved microwave conductivity measurements, in conjunction with transient absorption spectroscopy, clearly indicate that the nanofiber of 2 Amphi intrinsically allows for better carrier generation and transport properties than the microfibrous assembly of 2 Lipo . 相似文献
198.
Inubushi Y Horike S Fukushima T Akiyama G Matsuda R Kitagawa S 《Chemical communications (Cambridge, England)》2010,46(48):9229-9231
The structural flexibility of Cu(2+) interdigitated layer type framework was controlled and the compound represented clear separation property of CH(4)/CO(2) at range of 0-1.0 MPa and recovery of adsorbed CO(2) above 0.1 MPa. 相似文献
199.
Yui T Kobayashi Y Yamada Y Tsuchino T Yano K Kajino T Fukushima Y Torimoto T Inoue H Takagi K 《Physical chemistry chemical physics : PCCP》2006,8(39):4585-4590
Photochemical Electron Transfer (ET) between an organic dye, the porphyrin derivative TMPyP, and an electron acceptor, methyl viologen MV2+, have been investigated at the interface of two different inorganic films, i.e., layered titania nano-sheets (TNS) and a monolayer film of spherical and mono-dispersed mesoporous silica (sMPS) particles (ca. 0.5 microm). TMPyP ions were intercalated within the sMPS nano-cavities to form (TMPyP-sMPS) while MV2+ ions were intercalated into the TNS interlayers to form (MV2+-TNS). The (TMPyP-sMPS) and (MV2+-TNS) films were then stacked on a silica substrate in this order to form a (MV2+-TNS)/(TMPyP-sMPS) film and, upon UV light irradiation, ET could be induced. However, when this film was stacked inversely, i.e., for the (TMPyP-sMPS)/(MV2+-TNS) films on a silica substrate, no photoinduced ET were observed. Interestingly, however, even for this photo-inactive inversely stacked film, ET could be generated by inserting a gold vapor-deposited layer between the (MV2+-TNS) and (TMPyP-sMPS) films. The conjugation conditions at the interface of the inversely stacked (TMPyP-sMPS)/(MV2+-TNS) hybrid film were, thus, confirmed to strongly affect the photoinduced electron transfers and their efficiencies. 相似文献
200.
Critchley K Zhang L Fukushima H Ishida M Shimoda T Bushby RJ Evans SD 《The journal of physical chemistry. B》2006,110(34):17167-17174
We report thiol-on-gold self-assembled monolayers (SAMs) that can be photodeprotected using soft UV irradiation (lambda = 365 nm) to yield CO(2)H functionalized surfaces complementing those reported previously, which yielded NH(2) functionalized surfaces. The photolysis of these SAMs were monitored using a combination of surface sensitive techniques. In the SAM environment the photodeprotection yields are lower than those obtained for equivalent reactions in dilute solution. The protected carboxylic acids SAMs are shown to have a low yield approximately 50% due to competing photoreduction reactions of the nitro group. The results from infrared studies show that, as the photolysis progresses, the long chain protected residues reorganize and shield the functional COOH groups, thereby reducing the hydrophilic character of the surface. 相似文献