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101.
The electronic responses of duplex B-DNA sequences are investigated using perturbation theory analyses. The electronic polarizability and effective mass are computed for base pair doublets and triplets and the electronic structures are calculated according to density functional theory. High polarizability and a light effective mass are obtained in a sequence such as 5′-GGG-3′. The results indicate that the concentration of GC base pairs causes a high response of the electronic states, and molecular orbitals that are very responsive to the electric field tend to be reactive with other orbitals or conducting hole carriers. Furthermore, the interaction between the electronic states and a positively charged wavepacket is discussed, assuming hole injection in the DNA sequences. The sequence of 5′-GGG-3′ responds sensitively to the external hole approach, which is presumably injected to a guanine site. 相似文献
102.
Conductive polymer three-dimensional microstructures were photofabricated utilizing the two-photon absorption of a sensitizer
dye. The resulting three-dimensional structures were excised from the transparent polymer sheet using a micro-manipulator.
The processing precisions for the vertical direction of the conductive polymer three-dimensional microstructure obtained in
the transparent polymer sheet were evaluated in the present study. As a result, for the configurations of the obtained polypyrrole
line deposition, the line height/line width ratios were around 5: 1; this ratio is higher than that of other UV resin works
(h: w 2:4–3: 1) and the cross section distortion is not negligible for maintaining the higher reproducibility of the photofabrication. 相似文献
103.
Lingling Qiao Fei He Chen Wang Ya Cheng Koji Sugioka Katsumi Midorikawa 《Applied Physics A: Materials Science & Processing》2011,102(1):179-183
We report on the integration of microlens and microfluidic channels in fused silica glass chip using femtosecond laser micromachining.
The main process includes three procedures: (1) femtosecond laser scanning for forming a hemispherical surface and a Y-shaped
channel in the fused silica glass; (2) chemical etching of the sample for removal of the modified areas; and (3) oxyhydrogen
(OH) flame polish for smoothening the surface of the microlens. In addition, we demonstrate that the fabricated microlens
exhibits good imaging performance with a 5× magnification, showing great potential in future lab-on-a-chip applications. 相似文献
104.
105.
Shin Ichi Doi 《偏微分方程通讯》2013,38(1-2):163-178
106.
107.
Naoyuki Miyasaka Yoshihiro Doi Yukio Hinatsu 《Journal of solid state chemistry》2009,182(8):2104-2110
Synthesis, structures, and magnetic properties of ternary rare earth oxides ALnO2 (A=Cu or Ag; Ln=rare earths) have been investigated. CuLnO2 (Ln=La, Pr, Nd, Sm, Eu) were synthesized by the direct solid state reaction of Cu2O and Ln2O3, and AgLnO2 (Ln=Tm, Yb, Lu) were obtained by the cation-exchange reaction of NaLnO2 and AgNO3 in a KNO3 flux. These compounds crystallized in the delafossite-type structure with the rhombohedral 3R type (space group: R-3m). Magnetic susceptibility measurements showed that these compounds are paramagnetic down to 1.8 K. Specific heat measurements down to 0.4 K indicated that CuNdO2 ordered antiferromagnetically at 0.8 K. 相似文献
108.
Junya Kobayashi Motoo Kinoshita Jun-ichi Kita Katsumi Yoshino 《International Journal of Infrared and Millimeter Waves》1996,17(7):1149-1163
Experimental infrared modulator elements have been fabricated utilizing the transient light scattering effect of ferroelectric liquid crystal with asymmetric waveform voltage drive. The new elements perform 80% modulation degrees at the 632.8nm. We have also achieved 30% modulation degrees in the 4 to 5µ m region where the strongest CO2 absorption bands exist. A new type of analyzer which monitors ambient air quality has been developed. This analyzer uses non-dispersive infrared absorption method and composes of a double-beam, a single detector and a pair of liquid crystal light modulator as the IR chopper. The detection has achieved 10ppm noise equivalent concentration. 相似文献
109.
Takuya Shimosaka Masakazu Izako Katsumi Uchiyama Toshiyuki Hobo 《Analytical sciences》2005,21(4):469-472
In scanning microscopy by total internal reflection with thermal lens spectroscopy, its spatial resolution depends on the distance between the sample and a converging lens, which corresponds to the objective lens in an ordinary optical microscope. It was found that the resolution was best when the signal induced by the thermal lens effect was maximum. The distance was precisely adjusted by monitoring the signal intensity, and the resolution became twice better than that previously reported. Using a shorter focal-length lens, a resolution of 1.9 microm was attained. 相似文献
110.
Yukiko Furuhashi Pawel Sikorski Edward Atkins Tadahisa Iwata Yoshiharu Doi 《Journal of Polymer Science.Polymer Physics》2001,39(21):2622-2634
Poly(δ‐valerolactone) (PVL) crystals in the form of chain‐folded lamellae were prepared by isothermal crystallization from a 2‐methylbutane‐2‐ol solution. Wide‐angle and small‐angle X‐ray diffraction data, obtained from PVL lamellae sedimented to form oriented mats, were supplemented with morphological and structural data from electron microscopy, both imaging and diffraction. The diffraction signals index on an orthorhombic unit cell with the parameters a = 0.747 ± 0.002 nm, b = 0.502 ± 0.002 nm, and c (chain axis) = 0.742 ± 0.002 nm. Similar unit cell parameters were obtained from crystals grown from 1‐octanol and also from drawn melt‐pressed films. The evidence supports a model containing two antiparallel chain segments in the unit cell. The c value of 0.742 nm is appropriate for an all‐trans or onefold helical backbone conformation for the straight stems. Possible slight perturbations at the ester units from the all‐trans backbone conformation are discussed. Computerized modeling was used to optimize the adjacent‐reentry folded structure. The setting angles, with respect to the a axis, are ±58° for the corner and center chains. The lamellae are 7.26 ± 0.05 nm thick, and the chains run orthogonal to the lamellar surface. The chains fold in the diagonal (110) and (11¯0) planes in an alternating fashion. The X‐ray diffraction data suggest that a proportion of adjacent paired antiparallel entities, or hairpin units, are c‐axis‐sheared, and a relationship to the results obtained from drawn films is discussed. A brief comparison is also made with related polymer structures. © 2001 John Wiley & Sons, Inc. J Polym Sci Part B: Polym Phys 39: 2622–2634, 2001 相似文献