The Experts below are selected from a list of 321 Experts worldwide ranked by ideXlab platform

Kouta Mizuno - One of the best experts on this subject based on the ideXlab platform.

  • Study on plastic deformation in Cone-Type rotary piercing process using model piercing mill for modeling clay
    Journal of Materials Processing Technology, 2009
    Co-Authors: Kazutake Komori, Kouta Mizuno
    Abstract:

    Pierce rolling is the rolling performed first in the production of seamless pipes. In both barrel-Type rotary piercing and Cone-Type rotary piercing, the material is subjected to shearing deformation due to rotary forging. Only a few experimental studies on Cone-Type rotary piercing have been conducted to obtain the strain components. This paper describes the plastic deformation in the Cone-Type rotary piercing process using a model piercing mill with modeling clay. First, the model piercing mill is designed and fabricated, and then the effects of the cross-angle and feed angle on the strain components are clarified. It was found that, when the cross-angle is approximately 20°, the longitudinal section of the specimen before rolling becomes the longitudinal section of the specimen after rolling, irrelevant of the feed angle.

Kazutake Komori - One of the best experts on this subject based on the ideXlab platform.

  • Study on plastic deformation in Cone-Type rotary piercing process using model piercing mill for modeling clay
    Journal of Materials Processing Technology, 2009
    Co-Authors: Kazutake Komori, Kouta Mizuno
    Abstract:

    Pierce rolling is the rolling performed first in the production of seamless pipes. In both barrel-Type rotary piercing and Cone-Type rotary piercing, the material is subjected to shearing deformation due to rotary forging. Only a few experimental studies on Cone-Type rotary piercing have been conducted to obtain the strain components. This paper describes the plastic deformation in the Cone-Type rotary piercing process using a model piercing mill with modeling clay. First, the model piercing mill is designed and fabricated, and then the effects of the cross-angle and feed angle on the strain components are clarified. It was found that, when the cross-angle is approximately 20°, the longitudinal section of the specimen before rolling becomes the longitudinal section of the specimen after rolling, irrelevant of the feed angle.

Thomas G Ebrey - One of the best experts on this subject based on the ideXlab platform.

  • Chloride binding regulates the Schiff base pK in gecko P521 Cone-Type visual pigment.
    Biochemistry, 1999
    Co-Authors: Ching Yuan, Osamu Kuwata, Jie Liang, Saurav Misra, Sergei P. Balashov, Thomas G Ebrey
    Abstract:

    The binding of chloride is known to shift the absorption spectrum of most long-wavelength-absorbing Cone-Type visual pigments roughly 30 nm to the red. We determined that the chloride binding constant for this color shift in the gecko P521 visual pigment is 0.4 mM at pH 6.0. We found an additional effect of chloride on the P521 pigment:  the apparent pKa of the Schiff base in P521 is greatly increased as the chloride concentration is increased. The apparent Schiff base pKa shifts from 8.4 for the chloride-free form to >10.4 for the chloride-bound form. We show that this shift is due to chloride binding to the pigment, not to the screening of the membrane surface charges by chloride ions. We also found that at high pH, the absorption maximum of the chloride-free pigment shifts from 495 to 475 nm. We suggest that the chloride-dependent shift of the apparent Schiff base pKa is due to the deprotonation of a residue in the chloride binding site with a pKa of ca. 8.5, roughly that of the Schiff base in the abse...

  • The unique lipid composition of gecko (Gekko Gekko) photoreceptor outer segment membranes
    Comparative Biochemistry and Physiology B, 1998
    Co-Authors: Ching Yuan, Osamu Kuwata, Huiming Chen, Robert E. Anderson, Thomas G Ebrey
    Abstract:

    Abstract This study investigated the lipid and fatty acid composition of gecko photoreceptor outer segment membranes which contain the P521 Cone-Type pigment. The lipids of gecko photoreceptor outer segment membranes were first extracted and separated by thin layer chromatography (TLC) and then analyzed by gas chromatography (GC). Our results show that gecko photoreceptor outer segment membranes contain less phosphatidylethanolamine (PE) and more phosphatidylcholine (PC) and phosphatidylserine (PS) compared with those of bovine and frog. The content of the polyunsaturated fatty acid, docosahexaenoic acid (DHA), in PC and PS is also the highest yet reported (55 and 63%, respectively). These lipid differences may provide some insight into the specific lipid requirements of Cone-Type pigments.

  • Chloride effect on the early photolysis intermediates of a gecko Cone-Type visual pigment.
    Biochemistry, 1995
    Co-Authors: James W. Lewis, Thomas G Ebrey, Jie Liang, Mordechai Sheves, David S. Kliger
    Abstract:

    Nanosecond laser photolysis measurements were conducted on the Cone-Type visual pigment P521 in digitonin extracts of Tokay gecko (Gekko gekko) retina containing physiological chloride ion levels and also on samples which had been chloride depleted or which contained high levels (4 M) of chloride. Absorbance difference spectra were recorded at a sequence of time delays from 30 ns to 60 microseconds following excitation with a pulse of either 532- or 477-nm actinic light. Global analysis showed the kinetic decay data for gecko pigment P521 to be best fit by two exponential processes under all chloride conditions. The initial photoproduct detected had a broad spectrum characteristic of an equilibrated mixture of a Batho P521 intermediate with its blue-shifted intermediate (BSI P521) decay product. The first exponential process was assigned to the decay of this mixture to the Lumi P521 intermediate. The second exponential process was identified as the decay of Lumi P521 to Meta I P521. The initial photoproduct's spectrum exhibited a strong dependence on chloride concentration, indicating that chloride affects the composition of the equilibrated mixture of Batho P521 and BSI P521. These results suggest that the affinity for chloride is reduced approximately 5-fold in the Batho P521 intermediate and approximately 50-fold in the BSI P521 intermediate. Chloride concentration also affects the apparent decay rate of the equilibrated mixture. When the apparent decay rate is corrected for the composition of the equilibrated mixture, a relatively invariant microscopic rate constant is obtained for BSI decay (k = 1/55 ns-1).(ABSTRACT TRUNCATED AT 250 WORDS)

Gu Jian-nong - One of the best experts on this subject based on the ideXlab platform.

  • Numerical method of supercaviting flow past a slender Cone Type projectile traveling in water at subsonic speed
    Chinese Journal of Computational Mechanics, 2012
    Co-Authors: Gu Jian-nong
    Abstract:

    On the assumption that the ideal compressible fluid motion is irrotational and steady,supercavitating closure with the Riabushinsky scheme.An integro-differential equation for the supercavitating flow past a slender Cone Type projectile traveling in water at subsonic speed is derived based on the potential flow theory of hydrodynamics and the slender body theory.A numerical discrete method for solution of the integro-differential equation is developed,various initial solutions of supercavity profile are proposed and the influence on results are analyzed.The process of computation is optimized and the initial cavity solution for the first iteration is simplified.Compressibility influence of flow field on characteristic parameter of supercaviting flow is analyzed,while the Mach number exceeds 0.3,more remarkable increasement of supercavity shape and pressure coefficient on projectile surface and drag coefficient of projectile will occur.The calculated results about characteristic parameter of supercaviting flow are compared with relative theoretical and experimental ones,and a good agreement exists.

  • Numerical method of supercaviting flow past a slender Cone-Type projectile traveling in incompressible fluid
    Journal of Naval University of Engineering, 2011
    Co-Authors: Gu Jian-nong
    Abstract:

    By means of the ideal incompressible fluid motion which is irrotational and steady and supercavitating closure with the Riabushinsky scheme,an integro-differential equation was established for the supercavitating flow past a slender Cone Type projectile traveling in water based on the potential flow theory of hydrodynamics and the slender body theory.An numerical discrete method for solving the integro-differential equation was developed,and various initial solutions of supercavity profile were proposed and the influence on results were analyzed.The process of computation was optimized and the initial cavity solution for the first iteration was simplified.The calculated results about the characteristic parameters of supercaviting flow agree with the relative theoretical and experimental ones.

Simone Warzel - One of the best experts on this subject based on the ideXlab platform.

  • An invitation to trees of finite Cone Type: random and deterministic operators
    arXiv: Spectral Theory, 2014
    Co-Authors: Matthias Keller, Daniel Lenz, Simone Warzel
    Abstract:

    Trees of finite Cone Type have appeared in various contexts. In particular, they come up as simplified models of regular tessellations of the hyperbolic plane. The spectral theory of the associated Laplacians can thus be seen as induced by geometry. Here we give an introduction focusing on background and then turn to recent results for (random) perturbations of trees of finite Cone Type and their spectral theory.

  • On the spectral theory of trees with finite Cone Type
    Israel Journal of Mathematics, 2012
    Co-Authors: Matthias Keller, Daniel Lenz, Simone Warzel
    Abstract:

    We study basic spectral features of graph Laplacians associated with a class of rooted trees which contains all regular trees. Trees in this class can be generated by substitution processes. Their spectra are shown to be purely absolutely continuous and to consist of finitely many bands. The main result gives stability of the absolutely continuous spectrum under sufficiently small radially label symmetric perturbations for non-regular trees in this class. In sharp contrast, the absolutely continuous spectrum can be completely destroyed by arbitrary small radially label symmetric perturbations for regular trees in this class.

  • Absolutely continuous spectrum for random operators on trees of finite Cone Type
    arXiv: Mathematical Physics, 2011
    Co-Authors: Matthias Keller, Daniel Lenz, Simone Warzel
    Abstract:

    We study the spectrum of random operators on a large class of trees. These trees have finitely many Cone Types and they can be constructed by a substitution rule. The random operators are perturbations of Laplace Type operators either by random potentials or by random hopping terms, i.e., perturbations of the off-diagonal elements. We prove stability of arbitrary large parts of the absolutely continuous spectrum for sufficiently small but extensive disorder.

  • On the spectral theory of trees with finite Cone Type
    arXiv: Spectral Theory, 2010
    Co-Authors: Matthias Keller, Daniel Lenz, Simone Warzel
    Abstract:

    We study basic spectral features of graph Laplacians associated with a class of rooted trees which contains all regular trees. Trees in this class can be generated by substitution processes. Their spectra are shown to be purely absolutely continuous and to consist of finitely many bands. The main result gives stability of absolutely continuous spectrum under sufficiently small radially label symmetric perturbations for non regular trees in this class. In sharp contrast, the absolutely continuous spectrum can be completely destroyed by arbitrary small radially label symmetric perturbations for regular trees in this class.