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991.
Tokiyoshi Matsuda Mamoru Furuta Takahiro Hiramatsu Chaoyang Li Hiroshi Furuta Hitoshi Hokari Takashi Hirao 《Journal of Crystal Growth》2008,310(1):31-35
Undoped ZnO films were deposited by radio frequency (RF) magnetron sputtering on amorphous buffer layers such as SiOx, SiOxNy, and SiNx prepared by plasma enhanced chemical vapor deposition (PECVD) for dielectric layer in thin film transistor (TFT) application. ZnO was also deposited directly on glass and quartz substrate for comparison. It was found that continuous films were formed in the thickness up to 10 nm on all buffer layers. The crystallinity of ZnO films was improved in the order on quartz>SiOx >SiOxNy>glass>SiNx according to the investigated intensities of (0 0 2) XRD peaks. The crystallite sizes of ZnO were in the order of SiOx~glass >SiNx. Stable XRD parameters of ZnO thin films were obtained to the thickness from 40 to 100 nm grown on SiOx insulator for TFT application. Investigation of the ZnO thin films by atomic force microscope (AFM) revealed that grain size and roughness obtained on SiNx were larger than those on SiOx and glass. Hence, both nucleation and crystallinity of sputtered ZnO thin films remarkably depended on amorphous buffer layers. 相似文献
992.
Takahiro Yajima Hiroyuki Nagahama 《Nonlinear Analysis: Theory, Methods & Applications》2009,71(12):e203
The Rikitake system as nonlinear dynamical systems in geomagnetism can be studied based on the KCC-theory and the unified field theory. Especially, the behavior of the magnetic field of the Rikitake system is represented in the electrical system projected from the electro-mechanical unified system. Then, the KCC-invariants for the electrical and mechanical systems can be obtained. The third invariant as the torsion tensor expresses the aperiodic behavior of the magnetic field. Moreover, as a result of the projection, a protrusion between the mechanical and electrical systems is represented by the Euler-Schouten tensor. This Euler-Schouten tensor and the third invariant consist of the same mutual-inductance. Therefore, the aperiodic behavior of the magnetic field can be characterized by the protrusion between the electrical and mechanical systems. 相似文献
993.
Yusuke Sakai Yousuke Itoh Piljong Jung Keiko Kokeyama Chihiro Kozakai Katsuko T. Nakahira Shoichi Oshino Yutaka Shikano Hirotaka Takahashi Takashi Uchiyama Gen Ueshima Tatsuki Washimi Takahiro Yamamoto Takaaki Yokozawa 《Annalen der Physik》2024,536(2):2200140
Transient noise appearing in the data from gravitational-wave detectors frequently causes problems, such as instability of the detectors and overlapping or mimicking gravitational-wave signals. Because transient noise is considered to be associated with the environment and instrument, its classification would help to understand its origin and improve the detector's performance. In a previous study, an architecture for classifying transient noise using a time–frequency 2D image (spectrogram) is proposed, which uses unsupervised deep learning combined with variational autoencoder and invariant information clustering. The proposed unsupervised-learning architecture is applied to the Gravity Spy dataset, which consists of Advanced Laser Interferometer Gravitational-Wave Observatory (Advanced LIGO) transient noises with their associated metadata to discuss the potential for online or offline data analysis. In this study, focused on the Gravity Spy dataset, the training process of unsupervised-learning architecture of the previous study is examined and reported. 相似文献
994.
Tetsuya?SuekaneEmail author Na?Zhou Takahiro?Hosokawa Takuya?Matsumoto 《Transport in Porous Media》2010,82(1):111-122
We investigated the mechanism of residual gas trapping at a microscopic level. We imaged trapped air bubbles in a Berea sandstone
chip after spontaneous imbibition at atmospheric pressure. The pore structure and trapped bubbles were observed by microfocused
X-ray computed tomography. Distributions of trapped bubbles in Berea and Tako sandstone were imaged in coreflooding at a capillary
number of 1.0 × 10−6. Trapped bubbles are of two types, those occupying the center of the pore with a pore-scale size and others having a pore-network
scale size. In low-porosity media such as sandstone, connected bubbles contribute greatly to trapped gas saturation. Effects
of capillary number and injected water volume were investigated using a packed bed of glass beads 600μm in diameter, which
had high porosity (38%). The trapped N2 bubbles are stable against the water flow rate corresponding to a capillary number of 1.0 × 10−4. 相似文献
995.
Shinichi Saito Takahiro Yoshizawa Shinya Ishigami Ryu Yamasaki 《Tetrahedron letters》2010,51(46):6028-6030
The ring expansion reaction of ethyl cyclopropylideneacetate (1) with benzosilacyclobutenes proceeded smoothly in the presence of Ni(cod)2-TOPP (tribiphenyl-2-yl phosphite) to give benzosilacycloheptenes in good yields. This formal σ bond metathesis reaction proceeded in a selective manner. The Ni-catalyzed reaction of 1 with biphenylenes was also examined. 相似文献
996.
A novel type of waveguide quasi-phase-matched device with output electro-optical (EO) modulation is proposed and demonstrated. The second-harmonic generated output can be modulated with a high extinction ratio by integration of dual EO phase modulators on a periodically poled lithium niobate waveguide. Blue and green coherent light with EO modulation was demonstrated, and wavelength dispersion of r33 is discussed. 相似文献
997.
We have developed diffraction phase microscopy as a new technique for quantitative phase imaging of biological structures. The method combines the principles of common path interferometry and single-shot phase imaging and is characterized by subnanometer path-length stability and millisecond-scale acquisition time. The potential of the technique for quantifying nanoscale motions in live cells is demonstrated by experiments on red blood cells. 相似文献
998.
Yamada K Nemoto T Asanuma M Honda H Yamazaki T Hirota H 《Solid state nuclear magnetic resonance》2006,30(3-4):182-191
We have presented an experimental investigation of the carboxyl oxygen NMR parameters for four distinct sites in l-valine and l-isoleucine. The carboxyl (17)O quadrupolar coupling constant, C(Q), and isotropic chemical shift, delta(iso), for these compounds are obtained by analyzing two-dimensional (17)O multiple-quantum magic-angle spinning (MQMAS) and/or 1D MAS spectra. The values of C(Q) and delta(iso) found to be in the range of 7.00-7.85 MHz, and 264-314 ppm, respectively. Extensive quantum chemical calculations at the density functional levels have been performed for a full cluster of l-valine molecules and a few theoretical models. The calculated results indicated that there was a correlation between the (17)O NMR parameters and C-O bond lengths, which was helpful for the spectral assignment. They also demonstrated that the torsion angle of l-valine plays an important role in determining the magnitudes of (17)O NMR parameters. 相似文献
999.
Popescu G Ikeda T Goda K Best-Popescu CA Laposata M Manley S Dasari RR Badizadegan K Feld MS 《Physical review letters》2006,97(21):218101
Using a novel noncontact technique based on optical interferometry, we quantify the nanoscale thermal fluctuations of red blood cells (RBCs) and giant unilamellar vesicles (GUVs). The measurements reveal a nonvanishing tension coefficient for RBCs, which increases as cells transition from a discocytic shape to a spherical shape. The tension coefficient measured for GUVs is, however, a factor of 4-24 smaller. By contrast, the bending moduli for cells and vesicles have similar values. This is consistent with the cytoskeleton confinement model, in which the cytoskeleton inhibits membrane fluctuations [Gov et al., Phys. Rev. Lett. 90, 228101, (2003). 相似文献
1000.
Takahiro Tsushima 《Journal of Number Theory》2010,130(9):1932-1938
R. Coleman and W. McCallum calculated ramified components of the Jacobi sum Hecke characters explicitly using their computation of the stable reduction of the Fermat curve in Coleman and McCallum (1988) [CW]. In this paper, we give an elementary proof of the main result of them without using rigid geometry or the stable model of the Fermat curve. 相似文献