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301.
K. Sato T. Yamamoto T. Tezuka T. Ishibashi Y. Morishita A. Koukitu K. Machida T. Yamaoka 《Journal of magnetism and magnetic materials》2006
Regularly aligned arrays of magnetic nano dots buried in silicon wafers have been fabricated using damascene technique with the help of electron beam lithography. Arrays of square, rectangular, cross-shaped and Y-shaped structures of submicron size have been obtained. Spin distributions have been observed by means of magnetic force microscopy and analyzed by a micromagnetic simulation with Landau–Lifshitz–Gilbert equations. Importance of magnetostatic interactions working between adjacent dots has been elucidated. 相似文献
302.
M. Takigawa M. Ichioka K. Machida 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,27(3):303-311
Thermal conductivity κ
xx(T) under a field is investigated in d
x2 - y2-wave superconductors and isotropic s-wave superconductors by the linear response theory, using a microscopic wave function of the vortex lattice states. To study
the origin of the different field dependence of κxx(T) between higher and lower temperature regions, we analyze the spatially-resolved thermal conductivity around a vortex at
each temperature, which is related to the spectrum of the local density of states. We also discuss the electric conductivity
in the same formulation for a comparison.
Received 8 December 2001 and Received in final form 20 March 2002 Published online 6 June 2002 相似文献
303.
Four new 8-O-4' type neolignan glycosides with enantiometric aglycones, (7S,8R)-erythro-guaiacylglycerol-beta-O-4'-sinapyl ether 9-O-beta-D-glucopyranoside (1), (7R,8S)-erythro-guaiacylglycerol-beta-O-4'-sinapyl ether 9-O-beta-D-glucopyranoside (2), (7S,8R)-erythro- syringylglycerol-beta-O-4'-sinapyl ether 9-O-beta-D-glucopyranoside (3) and (7R,8S)-erythro- syringylglycerol-beta-O-4'-sinapyl ether 9-O-beta-D-glucopyranoside (4), were isolated from the leaves of Osmanthus ilicifolius. Their structures were established on the basis of NMR, circular dichroism (CD), MS and chemical data. The NMR assignments for the compounds were carried out using (1)H, (13)C, COSY, HMQC, HMBC and NOESY NMR experiments. 相似文献
304.
Bose-Einstein condensates which are dominated by magnetic dipole-dipole interaction are discussed under spinful situations. We treat the spin degrees of freedom as a classical spin vector, approaching from the large spin limit to obtain an effective minimal Hamiltonian. This is a version extended from a nonlinear sigma model. By solving the Gross-Pitaevskii equation, we find several novel spin textures where the mass density and spin density are strongly coupled, depending upon trap geometries due to the long-range and anisotropic natures of the dipole-dipole interaction. 相似文献
305.
Shin-ichi Machida Hisako Hirai Yoshitaka Yamamoto 《Journal of Physics and Chemistry of Solids》2010,71(9):1324-1328
Raman studies of a high-pressure structure of hydrogen hydrate, a filled ice Ic structure, were performed using a diamond anvil cell in the pressure range 3.2-44.1 GPa. The Raman spectra of a vibron revealed that extraction of hydrogen molecules from the filled ice Ic structure occurred above 20 GPa. In addition, the Raman spectra of a roton revealed that a rotation of hydrogen molecules in the filled ice Ic structure was suppressed at around 20 GPa and then the rotation recovered, and the rotation of hydrogen molecules was suppressed again above 35.5 GPa. These results indicate that intermolecular interactions increased between guest hydrogen molecules and host water molecules at around 20 and 35.5 GPa. These intermolecular interactions were considered to be induced to stabilize the filled ice Ic structure. Above 40 GPa, symmetrization of hydrogen bond was considered to contribute to the stability of hydrogen hydrate. 相似文献
306.
Machida S Watanabe-Nakayama T Saito M Afrin R Ikai A 《Micron (Oxford, England : 1993)》2012,43(12):1380-1389
The atomic force microscope (AFM) is a highly successful instrument for imaging of nanometer-sized samples and measurement of pico- to nano-Newton forces acting between atoms and molecules, especially in liquid. Generally, commercial AFM cantilevers, which have a sharp tip, are used for AFM experiments. In this review, we introduce micro-fabricated AFM cantilevers and show several applications for cell biology. In manipulation of samples on a cellular scale with a force of tens to hundreds of nano-Newtons, attempts have been made to secure the formation of covalent/non-covalent linkages between the AFM probe and the sample surface. However, present chemistry-based modification protocols of cantilevers do not produce strong enough bonds. To measure the tensile strength and other mechanical properties of actin-based thin filaments in both living and semi-intact fibroblast cells, we fabricated a probe with a hooking function by focused ion beam technology and used it to capture, pull and eventually break a chosen thin filament, which was made visible through fusion with fluorescent proteins. Furthermore, we fabricated a microscoop cantilever specifically designed for pulling a microbead attached to a cell. The microscoop cantilevers can realize high-throughput measurements of cell stiffness. 相似文献
307.
Takehiro Yamaguchi Kazuyuki IguchiRai Moriya Tomoki Machida 《Journal of magnetism and magnetic materials》2012,324(5):849-852
We demonstrate electrical tunnel spin injection from a ferromagnet to graphene through a high-quality Al2O3 grown by atomic layer deposition (ALD). The graphene surface is functionalized with a self-assembled monolayer of 3,4,9,10-perylene tetracarboxylic acid (PTCA) to promote adhesion and growth of Al2O3 with a smooth surface. Using this composite tunnel barrier of ALD-Al2O3 and PTCA, a spin injection signal of ∼30 Ω has been observed from non-local magnetoresistance measurements at 45 K, revealing potentially high performance of ALD-Al2O3/PTCA tunnel barrier for spin injection into graphene. 相似文献
308.
309.
The near-infrared spectra of formamide and its N- and C-deuterated compounds in chloroform solutions were investigated and a perturbation calculation of the vibrational levels of these isotopic formamides was carried out. The trans-interaction constant and the cubic cross-term constants between the NH stretching and the CNH bending coordinates were found to be necessary to reproduce observed frequencies. The stretching potentials of the trans- and the cis-NH bonds show close correspondence with those of the free and the bonded NH bonds of o-bromoaniline. The correlation between the compliance constants and the change of the CH, CO, and NH bond lengths on the dissociation of the CN bond is discussed. 相似文献
310.