162,733 research outputs found
Lymphangiogenesis in myocardial remodelling after infarction
Ishikawa Y, Akishima-Fukasawa Y, Ito K, Akasaka Y, Tanaka M, Shimokawa R, Kimura-Matsumoto M, Morita H, Sato S, Kamata I & Ishii T (2007) Histopathology51, 345–35
A four-dimensional organoid system to visualize cancer cell vascular invasion
Yanagisawa, K.; Konno, M.; Liu, H.; Irie, S.; Mizushima, T.; Mori, M.; Doki, Y.; Eguchi, H.; Matsusaki, M.; Ishii, H. A Four-Dimensional Organoid System to Visualize Cancer Cell Vascular Invasion. Biology 2020, 9, 361
Optimization of EHL Lubrication Performance in Thrust Slide-Bearings of Scroll Compressors
Previous studies [Refs. 1, 2] revealed the formation of a uniform oil wedge at the periphery of the thrust plate, caused by the elastic deformation of the orbiting thrust plate due to the pressure difference across the orbiting thrust plate, is a significant factor in the high lubrication performance in thrust slide-bearings. In addition to the uniform wedge formation, the high oil film pressure also induces a local elastic deformation of the fixed thrust plate normal to its surface. The normal thrust plate deformation and the oil wedge effectively form an elasto-hydrodynamic-lubrication (EHL) pocket, even more effectively increasing the oil film pressure between the sliding surfaces, due to the envelopment of the oil, as confirmed in our companion paper [3], and an earlier, less-detailed contribution [4]. The present study focuses on aspects of EHL that have both positive and negative effects on the lubrication performance of the thrust slide-bearings in scroll compressors. Theoretical calculations using the average Reynolds equation and Patier-Chen solid contact theory, for the boundary of the local elastic deformation of the thrust slide-bearing, were conducted for a small cooling capacity scroll compressor driven at 3600 rpm with 0.1 kW. An approximate method was developed using characteristic curves to determine the oil film axial force, the average oil film thickness, the frictional force and the frictional coefficient. The calculations considered a variety of pressure differences due to the operation pressure and the thickness of thrust plate. Also cases with a fixed uniform wedge angle at the periphery were calculated. The calculated results suggest a possible maximum reduction in frictional coefficient of about 55% compared to that with a fixed uniform wedge angle. The reduction rate increases with decreasing thrust plate thickness, which, however, restricts the operation pressures to a lower pressure range. Design guidelines for optimizing EHL will be suggested. References: [1] Oku, T., Ishii, N., Anami, K., Knisely, C.W., Sawai, K., Morimoto, T., Hiwata, A. : Theoretical Model of Lubrication Mechanism in the Thrust Slide-Bearing of Scroll Compressors, HVAC&R Research Journal ASHRAE Vol.14, No.2, pp.239-358, 2008-3. [2] Ishii, N., Oku, T., Anami, K., Knisely, C.W., Sawai, K., Morimoto, T., Iida, N. : Experimental Study of the Lubrication Mechanism for Thrust Slide Bearings in Scroll Compressors, HVAC&R Research Journal ASHRAE Vol.14, No.2, 2008-4. [3] Ishii, N., Tsuji, T., Anami, K., Nokiyama, K., Morimoto, T., Sakuda, A., Oku, T., Sawai, K., Knisely, C.W., : “Hydrodynamic-Pressure-Induced Elastic Deformation of Thrust Slide-Bearings in Scroll Compressors and Oil Film Pressure Increase Due to Oil Envelopment,” abstract submitted to 2014 Purdue Herrick Conferences. [4] Ishii, N., Tsuji, T., Oku, T., Anami, K., Knisely, C.W., Nokiyama, K., Morimoto, T., Sakuda, A., Sawai, K. 2012 “Elasto-Hydrodynamic Lubrication Effect in Thrust-Slide Bearings of Scroll Compressors,” 2012 Purdue Conference Paper on (Paper 1438)
Electric Fields of an H-Plane Tapered Iris
Microwave electric fields of an X -band H -plane tapered iris are calculated and plotted using the moment method for the first time. The moment method results are compared with previously obtained experimental measurements and numerical results based on an equivalent circuit approach, giving confirmation that the tapered iris is both a reciprocal and asymmetrical network. The moment method results now reveal that the asymmetry stems from the asymmetry in the phase of the input and output voltage reflection coefficients, their magnitudes being equal
Time-Dependent Variational Approach to the Non-Abelian Pure Gauge Theory
The time-dependent variational approach to the pure Yang-Mills gauge theory,
especially a color su(3) gauge theory, is formulated in the functional
Schroedinger picture with a Gaussian wave functional approximation. The
equations of motion for the quantum gauge fields are formulated in the
Liouville-von Neumann form. This variational approach is applied in order to
derive the transport coefficients, such as the shear viscosity, for the pure
gluonic matter by using the linear response theory. As a result, the
contribution to the shear viscosity from the quantum gluons is zero up to the
lowest order of the coupling g in the quantum gluonic matter.Comment: 19 pages, no figures, using PTPTeX.cl
Single carbon nanotubes as ultrasmall all-optical memories
Performance improvements are expected from integration of photonic devices
into information processing systems, and in particular, all-optical memories
provide a key functionality. Scaling down the size of memory elements is
desirable for high-density integration, and the use of nanomaterials would
allow for devices that are significantly smaller than the operation
wavelengths. Here we report on all-optical memory based on individual carbon
nanotubes, where adsorbed molecules give rise to optical bistability. By
exciting at the high-energy tail of the excitonic absorption resonance,
nanotubes can be switched between the desorbed state and the adsorbed state. We
demonstrate reversible and reproducible operation of the nanotube optical
memory, and determine the rewriting speed by measuring the molecular adsorption
and desorption times. Our results underscore the impact of molecular-scale
effects on optical properties of nanomaterials, offering new design strategies
for photonic devices that are a few orders of magnitude smaller than the
optical diffraction limit.Comment: 8 pages, 6 figure
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