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601.
602.
A longer period of time was necessary to form anatase nanocrystals on silica–titania gel coatings at lower hot water treatment temperature, whereas considerable amounts of anatase nanocrystals were observed even at 38°C after a treatment of 65 h. The coatings pre-heated at 60°C for 1 h and treated with hot water at 55°C for 15 h showed higher photocatalytic activity for methylene blue bleaching than the coatings prepared under the conditions with higher processing temperature close to 100°C. Such a high photocatalytic activity of the coatings obtained through low processing temperatures can be ascribed to a large specific surface area of the coatings and a smaller crystal size of the precipitated anatase.  相似文献   
603.
Wood samples (Picea jezoensis Carr.) were treated with solutions of aqueous NaOH (0–0.20 concentration fraction) and each treated samples evaluated by dynamic mechanical analyses (DMA). NaOH treatment was shown to affect the interactions between microfibrils and the surrounding matrix and, in particular, the dynamics of methylol groups in the microfibrils. The former is not dependent on the degree of crystallization but rather on the eluviation of the matrix. The latter depends on the degree of crystallization. Alkali treatment induces changes in the polymer domains as a result of matrix eluviation. This decreases the dynamics of methylol groups at NaOH concentrations less than 0.11. On the other hand, alkali treatment causes non-crystallization at concentrations greater than 0.11, which quantitatively increases the flexibility of methylol groups. Crystallinity decreased, and main-chain dynamics increased, following treatment with highly concentrated NaOH solutions. The dynamics of lignin also increased due to weakened interactions with microfibrils due to non-crystallization.  相似文献   
604.
605.
In this paper, we develop a rank-mapping algorithm for an icosahedral grid system on a massive parallel computer with the 3-D torus network topology, specifically on the K computer. Our aim is to improve the weak scaling performance of the point-to-point communications for exchanging grid-point values between adjacent grid regions on a sphere. We formulate a new rank-mapping algorithm to reduce the maximum number of hops for the point-to-point communications. We evaluate both the new algorithm and the standard ones on the K computer, using the communication kernel of the Nonhydrostatic Icosahedral Atmospheric Model (NICAM), a global atmospheric model with an icosahedral grid system. We confirm that, unlike the standard algorithms, the new one achieves almost perfect performance in the weak scaling on the K computer, even for 10,240 nodes. Results of additional experiments imply that the high scalability of the new rank-mapping algorithm on the K computer is achieved by reducing network congestion in the links between adjacent nodes.  相似文献   
606.
Biped locomotion created by controlling methods based on zero-moment point has been realized in real world and been well verified its efficacy for stable walking. However, the walking strategies that have been proposed so far seems to avoid such considerations as slipping of foot on the floor, even though there should exist the slipping large or small in real world. In this research, a dynamical model of humanoid robot including slipping of foot is proposed, which is derived by the Newton–Euler method. To confirm the veracity of the derived dynamical model, the model has been verified from the view point that when all friction coefficients are identical to zero, the total kinetic energy should be conserved to be unchanged, and when the coefficients are not zero, the total kinetic energy should decrease monotonously.  相似文献   
607.
This paper discusses the pulse-type hardware neural networks (P-HNNs) that contain a central pattern generator (CPG) and a pulsewidth modulation (PWM) servomotor controller and the application to quadruped robots. The purpose of our study is mimicking the biological neural networks and reproducing the similar motion of the living organisms in the robot. The CPG of the living organism generates the walking rhythms. We mimicked this CPG by modeling the cell body and the synapse of the living organism. The developed CPG composed of the P-HNN output four pulse signal sequences and the four outputs are introduced to each leg of the quadruped robot. On the other hand, the angle of the servomotor is controlled by the PWM. The PWM is obtained by modeling the axon of the living organism. The CPG and the PWM servo control system perform the walking motion of the quadruped robot. Moreover, the gate pattern change of quadruped animals is reproduced by these P-HNNs.  相似文献   
608.
Manipulating suspended colloidal particles flowing through a microchannel is of interest in microfluidics and nanotechnology. However, the flow itself can affect the dynamics of these suspended particles via wall-normal “lift” forces. The near-wall dynamics of particles suspended in shear flow and subject to a dc electric field was quantified in combined Poiseuille and EO flow through a?~?30 μm deep channel. When the two flows are in opposite directions, the particles are attracted to the wall. They then assemble into very high aspect ratio structures, or concentrated streamwise “bands,” above a minimum electric field magnitude, and, it appears, a minimum near-wall shear rate. These bands only exist over the few micrometers next to the wall and are roughly periodic in the cross-stream direction, although there are no external forces along this direction. Experimental observations and dimensional analysis of the time for the first band to form and the number of bands over a field of view of ~?200 μm are presented for dilute suspensions of polystyrene particles over a range of particle radii, concentrations, and zeta potentials. To our knowledge, there is no theoretical explanation for band assembly, but the results presented here demonstrate that it occurs over a wide range of different particle and flow parameters.  相似文献   
609.
6,7-Dihydroxy-N-cyanomethyl-1,2,3,4-tetrahydroisoquinoline, a cyanomethyl derivative of dopamine formed from cigarette smoke, was found to inhibit the activity of tryptophan hydroxylase. The inhibition was non-competitive to the substrate L-tryptophan (the Ki value 7.25 +/- 0.81 microM), but not to the biopterin cofactor. The inhibition is irreversible. 6-Hydroxy-N-cyanomethyl-tetrahydro-beta-carboline, a cyanomethyl derivative of serotonin, is inactive towards the hydroxylase. 6,7-Dihydroxy-N-cyanomethyl-1,2,3,4-tetrahydroisoquinoline may affect the serotonin biosynthesis in vivo as a consequence of cigarette smoking.  相似文献   
610.
Kawata S  Minami K  Minami S 《Applied optics》1983,22(22):3593-3598
The maximum entropy method (MEM) is applied to the interferogram data obtained using the technique of Fourier transform spectroscopy for estimating its spectrum with a resolution far exceeding the value set by the spectrometer. For emission line data, the MEM process is directly used with the interferogram data in place of the regular Fourier transformation process required in Fourier transform spectroscopy. It produces a spectral estimate with an enhanced resolution. For absorption data with a broad background spectrum, the method is applied to a modified interferogram which corresponds to the Fourier transform of the absorptance spectrum. Two results are presented to demonstrate the power of the technique: for the visible emission spectrum of a spectral calibration lamp and for the infrared chloroform absorption spectrum. Included in the paper is a discussion of the problems associated with practical use of the MEM.  相似文献   
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