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Genebank ‐ in vitro propagation of potato and sweetpotato. CIP‐SOP056 V 3.0
This procedure describes the in vitro multiplication of potato and sweetpotato germplasm for international and national germplasm distribution, as well as, in vitro conservation, phytosanitary, and cryopreservation activities
Statistical Thermodynamics of Polymer Quantum Systems
Polymer quantum systems are mechanical models quantized similarly as loop
quantum gravity. It is actually in quantizing gravity that the polymer term
holds proper as the quantum geometry excitations yield a reminiscent of a
polymer material. In such an approach both non-singular cosmological models and
a microscopic basis for the entropy of some black holes have arisen. Also
important physical questions for these systems involve thermodynamics. With
this motivation, in this work, we study the statistical thermodynamics of two
one dimensional {\em polymer} quantum systems: an ensemble of oscillators that
describe a solid and a bunch of non-interacting particles in a box, which thus
form an ideal gas. We first study the spectra of these polymer systems. It
turns out useful for the analysis to consider the length scale required by the
quantization and which we shall refer to as polymer length. The dynamics of the
polymer oscillator can be given the form of that for the standard quantum
pendulum. Depending on the dominance of the polymer length we can distinguish
two regimes: vibrational and rotational. The first occur for small polymer
length and here the standard oscillator in Schr\"odinger quantization is
recovered at leading order. The second one, for large polymer length, features
dominant polymer effects. In the case of the polymer particles in the box, a
bounded and oscillating spectrum that presents a band structure and a Brillouin
zone is found. The thermodynamical quantities calculated with these spectra
have corrections with respect to standard ones and they depend on the polymer
length. For generic polymer length, thermodynamics of both systems present an
anomalous peak in their heat capacity
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An improved Couette high shear viscometer and its application to crystallization of polyethylene in simple shear.
Both the upper and lower shear rate ranges for a Couette-type high shear viscometer have been extended beyond those reported in the literature. This has been accomplished by: 1» Improved machining and lapping accuracy of precision steel cylinder (spindle and ring) combinations. 2. More effective temperature control and monitoring. 3. Standardized formats for test parameter and data recording. Simplified, but statistically valid, data analysis techniques. These and secondary improvements (self-aligning drive shafts of different diameters for different torques, a spindle depth placement tool, and computer compatible measurement output) have resulted in a high performance laminar shear viscometer of only modest complexity. Operational equations for this instrument are derived, and a complete operation procedure is given. Calibration data analysis shows a measurement accuracy of + 3% or better over most of its shear rate range. Application of this viscometer to the crystallization of polyethylene under simple shear is also demonstrated
Effective photon mass and exact translating quantum relativistic structures
Using a variation of the celebrated Volkov solution, the Klein-Gordon
equation for a charged particle is reduced to a set of ordinary differential
equations, exactly solvable in specific cases. The new quantum relativistic
structures can reveal a localization in the radial direction perpendicular to
the wave packet propagation, thanks to a non-vanishing scalar potential. The
external electromagnetic field, the particle current density and the charge
density are determined. The stability analysis of the solutions is performed by
means of numerical simulations. The results are useful for the description of a
charged quantum test particle in the relativistic regime, provided spin effects
are not decisive
Theory of deoplet vaporization in the region of the thermodynamic critical point
Droplet vaporization in region of thermodynamic critical poin
Hamiltonian and physical Hilbert space in polymer quantum mechanics
In this paper, a version of polymer quantum mechanics, which is inspired by
loop quantum gravity, is considered and shown to be equivalent, in a precise
sense, to the standard, experimentally tested, Schroedinger quantum mechanics.
The kinematical cornerstone of our framework is the so called polymer
representation of the Heisenberg-Weyl (H-W) algebra, which is the starting
point of the construction. The dynamics is constructed as a continuum limit of
effective theories characterized by a scale, and requires a renormalization of
the inner product. The result is a physical Hilbert space in which the
continuum Hamiltonian can be represented and that is unitarily equivalent to
the Schroedinger representation of quantum mechanics. As a concrete
implementation of our formalism, the simple harmonic oscillator is fully
developed.Comment: 19 pages, 2 figures. Comments and references added. Version to be
published in CQ
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