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31.
32.
Hideo Soga 《Communications in Mathematical Physics》1990,133(1):37-52
In the first half of this paper, we construct asymptotic solutions of linear anisotropic elastic equations. In the latter half, we investigate waves reflected by boundaries for plane incident waves in terms of these solutions. Especially, it is examined whether or not the mode-conversion occurs near points where the incident waves hit the boundaries perpendicularly. 相似文献
33.
Kecheng Xiao Hideo Ogawa Hideo Suzuki Yasuo Fukui 《International Journal of Infrared and Millimeter Waves》1998,19(1):15-31
A heterodyne receiver based on a 1/3 reduced height rectangular waveguide SIS mixer with two mechanical tuners has been built for astronomical observations of molecular transitions in the 230 GHz frequency band. The mixer used an untuned array (RnCj3, Rn70 ) of four Nb/AIOx/Nb tunnel junctions in series as a nonlinear mixing element. A reasonable balance between the input and output coupling efficiencies has been obtained by choosing the junction number N=4. The receiver exhibits DSB (Double Side Band) noise temperature around 50 K over a frequency range of more than 10 GHz centered at 230 GHz. The lowest system noise temperature of 38 K has been recorded at 232.5 GHz. Mainly by adjusting the subwaveguide backshort, the SSB (Single Side Band) operation with image rejection of 15 dB is obtained with the noise temperature as low as 50 K. In addition, the noise contribution from each receiver component has been studied further. The minimum SIS mixer noise temperature is estimated as 15 K, pretty close to the quantum limit v/k11 K at 230 GHz. It is believed that the receiver noise temperatures presented are the lowest yet reported for a 230 GHz receiver using untuned junctions. 相似文献
34.
Advanced high-pressure plasma diagnostics with hairpin resonator probe surrounded by film and sheath 下载免费PDF全文
The hairpin probe using microwave resonance in plasma is applicable to high pressure 1.33×10 3-1.01×10 5 Pa)) as developed recently.In this work,an analytic model of the hairpin resonator probe surrounded by a thin dielectric layer and a sheath layer is proposed.The correction factor due to these surroundings is analytically found and confirmed by electromagnetic field finite difference time domain simulation,thus enabling the accurate measurement of electron density in a high-pressure non-equilibrium uniform discharge. 相似文献
35.
We show that an isolated singularity at the origin 0 of a smooth solution (u,p) of the stationary Navier-Stokes equations is removable if the velocity u satisfies u∈Ln or |u(x)|=o(|x|-1) as x→0. Here n?3 denotes the dimension. As a byproduct of the proof, we also obtain a new interior regularity theorem. 相似文献
36.
Hideo Kaiju Akito Ono Kenji Kondo Jonghan Won Manabu Ishimaru 《Applied Surface Science》2009,255(6):3706-3712
We study the structural properties of the surface roughness, the surface mound size and the interfacial structure in Ni thin films vacuum-deposited on polyethylene naphthalate (PEN) organic substrates with and without the application of magnetic field and discuss its feasibility of fabricating quantum cross (QC) devices. For Ni/PEN evaporated without the magnetic field, the surface roughness decreases from 1.3 nm to 0.69 nm and the surface mound size increases from 32 nm to 80 nm with the thickness increased to 41 nm. In contrast, for Ni/PEN evaporated in the magnetic field of 360 Oe, the surface roughness tends to slightly decrease from 1.3 nm to 1.1 nm and the surface mound size shows the almost constant value of 28-30 nm with the thickness increased to 35 nm. It can be also confirmed for each sample that there is no diffusion of Ni into the PEN layer, resulting in clear Ni/PEN interface and smooth Ni surface. Therefore, these experimental results indicate that Ni/PEN films can be expected as metal/insulator hybrid materials in QC devices, leading to novel high-density memory devices. 相似文献
37.
The heterotrich ciliate Blepharisma japonicum produces red pigment blepharismins, which function as self-defense toxin against predators and as a photoreceptor for step-up photonegativity. The dibenzoperylenequinone moiety of blepharismins was shown to be biosynthesized via the polyketide pathway. In this paper, the starter units of the biosynthetic pathway of blepharismins were determined to be isovaleryl-CoA and butyryl-CoA by HPLC, LC/ESI-MS, and 1H and 2H NMR analyses of the pigments obtained from feeding experiment of l-leucine or sodium butyrate in excess and deuterium-labeled l-leucine. 相似文献
38.
Hideo Maehata Xinzhi Liu Michael Cunningham Barkev Keoshkerian 《Macromolecular rapid communications》2008,29(6):479-484
While miniemulsion polymerization has proven to be well‐suited for conducting living/controlled radical polymerizations, emulsion polymerizations have proven to be far more challenging. Ab initio emulsion polymerizations, in which monomer droplets are present during polymerization, have thus far not been successful with TEMPO‐mediated polymerizations, as a result of colloidal instability and coagulum formation. By selectively inhibiting polymerization in the monomer droplets, it is demonstrated that droplet polymerization is responsible for the formation of large (>1 µm) particles that can lead to coagulum formation. Furthermore, we show that coagulum‐free latexes can be produced using a TEMPO‐mediated ab initio emulsion polymerization by suppressing droplet polymerization.
39.
Izumi T Naitou Y Shimbo Y Takanishi Y Takezoe H Watanabe J 《The journal of physical chemistry. B》2006,110(47):23911-23919
The mesomorphic behavior and phase structure were examined in the mixture of two kinds of dimeric compounds, alpha,omega-bis(4-alkoxyanilinebenzylidene-4'-carbonyloxy)pentane (mOAM5AMOm), by optical microscopy, X-ray diffraction, polarization switching, and second-harmonic generation measurements. One compound is 4OAM5AMO4 with a short terminal alkyl chain that forms a single-layer smectic phase (SmCAs) with a random mixing of spacer and tail groups. Another compound is 16OAM5AMO16 with a long terminal alkyl chain that forms a chiral, anticlinic, and antiferroelectric bilayer phase (SmCAb) with the bent molecules tilted to the bilayer. By mixing these two compounds, the SmCAs phase of 4OAM5AMO4 is easily destabilized, leading to the wide content region of the bilayer phases. In the bilayer regime, three other smectic phases are newly induced. Two of them are antiferroelectric and ferroelectric phases in which the molecules lie perpendicularly with respect to the layer. The other shows no polar response to an external electric field and behaves like a smectic A. The new appearance of these bilayer phases is discussed as a mixing effect of long and short tail groups. 相似文献
40.
A significant acceleration effect of a beta-silicon atom was observed on the electrocyclic ring-opening reaction of benzocyclobutene derivatives to form o-quinodimethanes. This acceleration effect could be attributed to an electronic sigma-donating nature of the C(alpha)-Si(beta) bond, associated with alpha-anion driven pericyclic reactions. 相似文献