The Experts below are selected from a list of 9825 Experts worldwide ranked by ideXlab platform

T O Grady - One of the best experts on this subject based on the ideXlab platform.

  • cuticular changes and structural dynamics in the fourth stage larvae and adults of ascaris suum goeze 1782 nematoda ascaridoidea developing in swine
    2007
    Co-Authors: T O Grady
    Abstract:

    O'GRADY, R. T. 1983. Cuticular changes and structural dynamics in the fourth-stage larvae and adults of Ascaris suum Goeze, 1782 (Nematoda: Ascaridoidea) developing in swine. Can. J . Zool. 61: 12931303. Fourth-stage larvae and adults of Ascaris suum recovered from pigs at 11 days after infection (DAI) to maturity were examined by light and scanning electron microscopy for changes in the cuticle. Allometric body growth in the larva affects the structure of the cuticle in three ways. First, there is increasing separation of the external striae and incomplete longitudinal ridges which closely follows the longitudinal and circumferential expansion of the body. Second, although the cuticle increases in absolute thickness, its thickness in relation to the midbody diameter decreases. Third, the Spiral fibre system in the basal layer is elongated, causing a decrease in the Spiral Angle. All three of these changes are the reverse of that which occurs in the adult cuticle after the fourth moult at 22 D A ~ . An analysis of the structural dynamics of the larval cuticle shows the decreased Spiral Angle to be approaching the functional limit of a hydrostatic skeleton enclosed within an anisometric exoskeleton.

N F Ness - One of the best experts on this subject based on the ideXlab platform.

  • voyager 1 observations of the interstellar magnetic field and the transition from the heliosheath
    Journal of Physics: Conference Series, 2015
    Co-Authors: L F Burlaga, N F Ness
    Abstract:

    Voyager 1 (V1) has been observing interstellar magnetic fields (ISMF) for more than one year, from 2012/209 to at least 2013.6. From 2013.0 to 2013.6 the difference between the azimuthal Angle of the ISMF and the Parker Spiral Angle at the latitude 34.6° of V1 was (22 ± 3)° and the corresponding difference of the elevation Angle was (0 ± 8)°. During 2012 the deviation from the Parker Spiral Angle was somewhat smaller. The interstellar magnetic field has a West to East polarity, opposite to the direction of planetary motions. The magnitude of the ISMF varied smoothly in the range 0.38 nT to 0.59 nT with an average strength 0.49nT. The strongest interstellar fields were observed behind a shock at 2012/297 that was preceded by 2.2 KHz plasma oscillations, which implies an interstellar electron density ne = 0.05/cm−3. The ISMF was observed after V1 crossed a current sheet CS0 having the structure of a tangential discontinuity. The inclination of this current sheet is consistent with an interstellar magnetic field draped on a blunt heliopause. Two other current sheets (sector boundaries) were observed earlier in the heliosheath at 2012/167 and 2011/276 with high inclinations (99 +/−10)° and (89 ± 10)°, respectively). The transition from heliosheath to interstellar magnetic fields is related to a two-step increase in the cosmic ray intensity observed by V1 from 2012.30 to 2012.65. The first step-increase began near the end of an unusual away-polarity sector, and it reached a plateau when V1 moved into a toward-polarity sector that ended at CS0. The second step-increase began slowly after V1 crossed CS0, and it ended abruptly at 2012/237.728.

  • voyager 1 observations of the interstellar magnetic field and the transition from the heliosheath
    The Astrophysical Journal, 2014
    Co-Authors: L F Burlaga, N F Ness
    Abstract:

    Voyager 1 (V1) has been observing interstellar magnetic fields for more than one year beginning ≈2012/209, when V1 crossed a current sheet, a "CS0" having the structure of a tangential discontinuity. The inclination of this current sheet is consistent with an interstellar magnetic field B draped on a blunt heliopause. Two other current sheets (sector boundaries) were observed at ≈2012/167 and ≈2011/276 with high inclinations (99° ± 10° and 89° ± 10°, respectively). From 2013.0 to ≈2013.6, the difference between the azimuthal Angle λ of B from the Parker Spiral Angle at the latitude 346 of V1 was λ – λP = 22° ± 3° and the corresponding difference of the elevation Angle δ was δ – δP = 23° ± 8°. During 2012, the deviation from the Parker Spiral Angle was somewhat smaller. The interstellar magnetic field has a "west to east polarity," opposite to the direction of planetary motions. The magnitude of B varied smoothly in the range 0.38-0.59 nT with an average B = 0.486 ± 0.045 after 2012/237.7. The transition from heliosheath to interstellar magnetic fields is related to a "two-step" increase in the cosmic ray intensity observed by V1 from ≈2012.30 to ≈2012.65. The first step increase began near the end of an unusual "away-polarity" sector, and it reached a plateau when V1 moved into a "toward-polarity" sector that ended at CS0. The second step increase began slowly after V1 crossed CS0, and it ended abruptly at 2012/237.728.

Tieming Xiang - One of the best experts on this subject based on the ideXlab platform.

  • the meshing angular velocity and tangential contact force simulation for logarithmic Spiral bevel gear based on hertz elastic contact theory
    Journal of Mechanical Science and Technology, 2016
    Co-Authors: Tieming Xiang
    Abstract:

    To obtain the change tendency of output angular velocity and tangential contact force of a gear when the pinion under the step input during meshing of a new type of Spiral bevel gear, which is a logarithmic Spiral bevel gear, the tooth flank equation of logarithmic Spiral bevel gear is deduced based on the formation mechanism of the tooth flank formation. A three-dimensional model of a pair of logarithmic Spiral bevel gears whose number of teeth was 37:9, with modules being 4.5 mm, normal pressure Angle being 20 degrees and Spiral Angle being 35 degrees were built and assembled. Based on Hertz elastic contact theory, the calculation formulas and parameters sets of contact force for conventional Spiral bevel gear meshing simulation and logarithmic Spiral bevel gear meshing simulation were done. Consider the dynamic simulation about meshing angular velocity and tangential contact force for conventional Spiral bevel gear meshing and logarithmic Spiral bevel gear meshing, respectively. Finally, by analyzing and comparing the simulation data, the results show that under the same input conditions, the fluctuation of the gear angular velocity and tangential contact force of logarithmic Spiral bevel gear meshing are smaller than the conventional Spiral bevel gear. That is, the transmission stationary of logarithmic Spiral bevel gear meshing is superior to conventional Spiral bevel gear.

Zhou Peiyan - One of the best experts on this subject based on the ideXlab platform.

  • numerical analysis on a new pump out hydrodynamic mechanical seal
    Tribology International, 2017
    Co-Authors: Sun Jianjun, Ma Chenbo, Yu Qiuping, Lu Jianhua, Zhou Min, Zhou Peiyan
    Abstract:

    Abstract A new pump-out hydrodynamic mechanical seal with self-pumping effect is presented based on centrifugal pump's working principle. Results of parametric study show that both of the opening force and leakage rate increase with increasing medium pressure, channel diameter, Spiral Angle and width ratio of groove to ridge; The opening force increases with decreasing groove number and length ratio of groove to dam while the leakage rate decreases slightly; There exits an optimum groove depth that obtains higher opening force along with lower leakage rate. Moreover, the new mechanical seal can be used in conditions with larger pressure difference.

Hans Nilsson - One of the best experts on this subject based on the ideXlab platform.