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481.
In order to investigate the allotropic effect on ripple pattern formation, highly oriented pyrolytic graphite (HOPG) and single crystalline diamond were irradiated with 10-200 keV Xe+ at an incident angle of 60° with respective to the surface normal. The irradiation fluence was 2 × 1017 cm−2 for all irradiations. Ripple patterns were observed on both HOPG and diamond surfaces. However, large differences in ripple wavelengths, amplitudes and surface roughnesses between HOPG and diamond were recognized. The reason for these differences is discussed. 相似文献
482.
Photoinduced electron‐transfer reactions of tris(2,2′‐bipyridine)ruthenium(II)‐based carbonic anhydrase inhibitors tethering plural binding sites 下载免费PDF全文
Mikiko Suwa Narumi Imamura Pirika Awano Eiji Nakata Hiroshi Takashima 《Journal of Physical Organic Chemistry》2018,31(9)
Tris(2,2′‐bipyridine)ruthenium(II) complex‐based carbonic anhydrase (CA) inhibitors, [Ru(bpy)2(bpydbs)]2+ {bpy = 2,2′‐bipyridine and bpydbs = 2,2′‐bipyridinyl‐4,4′‐dicarboxilic acid bis[(2‐{2‐[2‐(4‐sulfamoylbenzoylamino)ethoxy]ethoxy}ethyl)amide]} and [Ru(bpydbs)3]2+, tethering plural benzenesulfonamide groups have been prepared. The CA catalytic activity was effectively suppressed by these synthetic [Ru(bpy)2(bpydbs)]2+ and [Ru(bpydbs)3]2+ inhibitors, and their dissociation constants at pH = 7.2 and at 25°C were determined to be KI = 0.93 ± 0.02 μM and KI = 0.24 ± 0.03 μM, respectively. Next, 2 photoinduced electron‐transfer (ET) systems comprising a Ru2+‐CA complex and an electron acceptor, such as chloropentaamminecobalt(III) ([CoCl(NH3)5]2+) or methylviologen (MV2+) were studied. In the presence of CA and a sacrificial electron acceptor, such as pentaamminechlorocobalt(III) complex, the photoexcited triplet state of 3([Ru(II)]2+)* was quenched through an intermolecular photoinduced ET mechanism. In case of the [Ru(bpydbs)3]2+‐CA‐MV2+ system, the photoexcited triplet state of 3([Ru(bpydbs)3]2+)* was quenched by sacrificial quencher through an intermolecular photoinduced ET mechanism, giving the oxidized [Ru(bpydbs)3]3+. Then the following intramolecular ET from the amino acid residue, Tyr6, near the active site of CA proceeded. We observed a transient absorption around at 410 nm, arising from the formation of a Tyr?+ in the [Ru(bpydbs)3]2+‐CA‐MV2+ system. These artificial Ru(II)‐CA systems may clearly demonstrate both intermolecular and intramolecular photoinduced ET reactions of protein and could be one of the interesting models of the ET proteins. Their photophysical properties and the detailed ET mechanisms are discussed in order to clarify the multistep ET reactions. 相似文献
483.
A. A. Kaminskii H. Rhee H. J. Eichler K. Ueda K. Oka H. Shibata 《Applied physics. B, Lasers and optics》2008,93(4):865-872
We report the experimental investigations of nonlinear-laser effects in LuVO4 vanadate under one-micron picosecond Nd3+:Y3Al5O12 pumping. In this tetragonal host-crystal for Ln3+ lasants for the first time we excited ultra-broad, more than one and half octave (13500 cm−1) Raman induced Stokes and anti-Stokes generation combs and observed multi-step cascaded parametric χ
(3)-lasing in UV spectral region. All generation lines were identified and attributed to SRS-promoting modes of the crystal (ω
SRS1≈900 cm−1 and ω
SRS2≈113 cm−1). We classified this vanadate as a promising material for self-Raman laser converters. 相似文献
484.
A Mueller matrix polarimeter acquired for four-channeled spectra is proposed. Both the polarizing and analyzing optics of this system consist of a linear polarizer and a high-order retarder. The polarizing elements can modulate the polarization states in the wavenumber space. By applying a Fourier transform method to a single-channeled spectrum, nine elements of the Mueller matrix can be deconvoluted without modifying the configuration of either the polarizing or analyzing optics. It is thus possible to determine the wavelength dependence of all the Mueller matrix elements from four-channeled spectra obtained using four different configurations for the polarizing and analyzing optics. The performance of this method is evaluated by measuring polarization properties, such as retardance, azimuthal angle, and linear diattenuation, from the obtained Mueller matrix in wavenumber space. 相似文献
485.
486.
Uchiyama S Kawai N de Silva AP Iwai K 《Journal of the American Chemical Society》2004,126(10):3032-3033
We illustrate a general polymeric design of fluorescent logic gates, for example, AND, using temperature and pH as inputs. 相似文献
487.
Quantum transport properties of electron systems driven by strong electric fields are studied by mapping the Landau-Zener transition dynamics to a quantum walk on a semi-infinite one-dimensional lattice with a reflecting boundary, where the sites correspond to energy levels and the boundary the ground state. Quantum interference induces a distribution localized around the ground state, and a delocalization transition occurs when the electric field is increased, which describes the dielectric breakdown in the original electron system. 相似文献
488.
Yamamoto S Toi K Nakajima N Ohdachi S Sakakibara S Watanabe KY Goto M Ikeda K Kaneko O Kawahata K Masuzaki S Morisaki T Morita S Murakami S Narihara K Oka Y Osakabe M Takeiri Y Tanaka K Tokuzawa T Tsumori K Yamada H Yamada I Yamazaki K;LHD Experimental Group 《Physical review letters》2003,91(24):245001
The helicity-induced Alfvén eigenmodes (HAEs) with the toroidal mode number n=2 and 3 are observed for the first time in the Large Helical Device plasmas heated by neutral beam injection. The observed mode frequency is about 8 times higher than that of the observed toroidicity-induced Alfvén eigenmodes, and is proportional to the Alfvén velocity. The modes are excited when the ratio of the beam velocity to the Alfvén velocity exceeds about unity. The frequency lies just above the lower bound of the HAE gap in the plasma edge region of rho>0.7 (rho: normalized minor radius). 相似文献
489.
The Atiyah-Manton (AM) construction based on instantons is used to construct skyrmions. For baryon number one, an analytic form for the skyrmion is obtained that compares well with the exact solution. For baryon number two, we study skyrmion interactions and distortion as a function of relative distance and orientation. From this we project out a nucleon-nucleon interaction. We find the principal features of the nuclear force but still no intermediate-range attraction. We compare the AM construction with the product ansatz. 相似文献
490.