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121.
Hypochromic effects of 2-(thymin-1-yl)propionyl graft polyethylenimine (P-T) and its related monomer (M-T) and dimer model (D-T), and 2-(adenin-9-yl)propionyl graft polyethylenimine (P-A) and its monomer (M-A) and dimer model (D-A) have been systematically investigated, and the base-stacked conformation in comparison with corresponding polynucleotides and dinucleotides has been discussed. The results suggest that the graft polymers and even their dimer models may have a particular preference for a stacked conformation compared with the corresponding poly- and dinucleotides. A study of solvent effect on the NMR spectra of the dimer model suggests the existence of a preferred base-stacked conformation. Base pairing effects between the complementary bases have also been studied for various combinations among the model systems. Only the combination P-T/P-A showed a considerable hypochromic effect. 相似文献
122.
M. Tanemura T. Okita J. Tanaka H. Yamauchi L. Miao S. Tanemura R. Morishima 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2005,34(1-3):283-286
Glassy carbon plates, a Ni mesh coated with a carbon film and mechanically
polished graphite plates were Ar+ ion-bombarded with and without a
simultaneous Mo supply at room temperature. Conical protrusions were formed
on the sputtered surfaces, and in some cases carbon nanofibers (CNFs) 0.2–10 μm in length and 10–50 nm in diameter grew on the tips. The growth of CNF-tipped-cones was optimized in terms of the ion-incidence angle and the rate-ratio of sputtering and seeding. Oblique sputtering was proved to
be quite effective to grow the CNF-tipped-cones. Thus, the redeposited massive carbon atoms onto cones were thought to diffuse toward the cone tips, resulting in CNF formation. This growth mechanism was confirmed by transmission electron microscope (TEM) observation disclosing the
boundary-less structure between conical bases and CNFs. TEM observation of
CNF-tipped-cones also revealed no-hollow structure and an amorphous nature
of CNFs. Since this sputtering method is a room-temperature process and
quite straightforward, ion-induced CNFs promise to have myriad applications,
such as field emission sources for flat panel displays. 相似文献
123.
124.
Oshige M Kawasaki S Takano H Yamaguchi K Kurita H Mizuno T Matsuura S Mizuno A Katsura S 《Journal of fluorescence》2011,21(3):1189-1194
Direct observation studies of single molecules have revealed molecular behaviors usually hidden in the ensemble and time-averaging
of bulk experiments. Direct single DNA molecule analysis of DNA metabolism reactions such as DNA replication, repair, and
recombination is necessary to fully understand these essential processes. Intercalation of fluorescent dyes such as YOYO-1
and SYTOX Orange has been the standard method for observing single molecules of double-stranded DNA (dsDNA), but effective
fluorescent dyes for observing single molecules of single-stranded DNA (ssDNA) have not been found. To facilitate direct single-molecule
observations of DNA metabolism reactions, it is necessary to establish methods for discriminating ssDNA and dsDNA. To observe
ssDNA directly, we prepared a fusion protein consisting of the 70 kDa DNA-binding domain of replication protein A and enhanced
yellow fluorescent protein (RPA-YFP). This fusion protein had ssDNA-binding activity. In our experiments, dsDNA was stained
by SYTOX Orange and ssDNA by RPA-YFP, and we succeeded in staining ssDNA and dsDNA by using RPA-YFP and SYTOX Orange simultaneously. 相似文献
125.
126.
Daisuke Sakai Kenji Harada Shun-ichi Kamemaru Daisuke Barada Fuminobu Sato Takashi Fukuda 《Optical Review》2009,16(3):335-338
We propose a method of hologram recording in a glass plate by corona charging. The holographic recording materials used in
this study are conventional soda-lime glass and azobenzene polymer film. A Fourier transform hologram on an azobenzene polymer
film coated on the glass plate is recorded in the glass plate by corona charging. After removing the polymer film, the hologram
recorded in the plate can be reconstructed using a visible-wavelength laser beam. The first-order diffraction efficiency of
the hologram at a wavelength of 532 nm is 0.03%; the efficiency depends on the depth of the surface relief structure on the
azobenzene polymer film and the corona-charging time. The hologram recorded in the glass plate has high environmental resistance. 相似文献
127.
This paper addresses a piecewise affine (PWA) approximation problem, i.e., a problem of finding a PWA system model which approximates a given nonlinear system. First, we propose a new class of PWA systems, called the Lebesgue PWA approximation systems, as a model to approximate nonlinear systems. Next, we derive an error bound of the PWA approximation model, and provide a technique for constructing the approximation model with specified accuracy. Finally, the proposed method is applied to a gene regulatory network with nonlinear dynamics, which shows that the method is a useful approximation tool. 相似文献
128.
Shinsuke Umegaki Yoshinori Anabuki Ken-ichi Ohta Kyo Inoue Shun-ichi Tanaka 《Optics Communications》1983,45(2):80-83
An optical second-harmonic wave can be generated in a three-layered optical waveguide of arbitrary film thickness under phase-matching condition. Phase-matching is achieved by utilizing mode dispersion in an optical waveguide with a two-dimensional configuration. A numerical analysis of the matching condition is given and the results of the observation of the optical second-harmonic wave of a guided Nd : YAG laser in a Ti-indiffused LiNbO3 nonlinear film are described. 相似文献
129.
130.