1,107 research outputs found
Intrinsic localized modes in the charge-transfer solid PtCl
We report a theoretical analysis of intrinsic localized modes in a
quasi-one-dimensional charge-transfer-solid (PtCl). We discuss strongly nonlinear features of resonant Raman
overtone scattering measurements on PtCl, arising from quantum intrinsic
localized (multiphonon) modes (ILMs) and ILM-plus-phonon states. We show, that
Raman scattering data displays clear signs of a non-thermalization of lattice
degrees-of-freedom, manifested in a nonequilibrium density of intrinsic
localized modes.Comment: 4 pages, 4 figures, REVTE
A perturbative treatment for the energy levels of neutral atoms
Energy levels of neutral atoms have been re-examined by applying an
alternative perturbative scheme in solving the Schrodinger equation for the
Yukawa potential model with a modified screening parameter. The predicted shell
binding energies are found to be quite accurate over the entire range of the
atomic number up to 84 and compare very well with those obtained within the
framework of hyper-virial-Pade scheme and the method of shifted large-N
expansion. It is observed that the new perturbative method may also be applied
to the other areas of atomic physics.Comment: 18 page
Bouncing Neutrons and the Neutron Centrifuge
The recent observation of the quantum state of the neutron bouncing freely
under gravity allows some novel experiments. A method of purifying the ground
state is given, and possible applications to the measurement of the electric
dipole moment of the neutron and the short distance behaviour of gravity are
discussed.Comment: 7 pages, 7 figure
Reconciling Semiclassical and Bohmian Mechanics: III. Scattering states for continuous potentials
In a previous paper [J. Chem. Phys. 121 4501 (2004)] a unique bipolar
decomposition, Psi = Psi1 + Psi2 was presented for stationary bound states Psi
of the one-dimensional Schroedinger equation, such that the components Psi1 and
Psi2 approach their semiclassical WKB analogs in the large action limit. The
corresponding bipolar quantum trajectories, as defined in the usual Bohmian
mechanical formulation, are classical-like and well-behaved, even when Psi has
many nodes, or is wildly oscillatory. A modification for discontinuous
potential stationary stattering states was presented in a second paper [J.
Chem. Phys. 124 034115 (2006)], whose generalization for continuous potentials
is given here. The result is an exact quantum scattering methodology using
classical trajectories. For additional convenience in handling the tunneling
case, a constant velocity trajectory version is also developed.Comment: 16 pages and 14 figure
Centrifugal quantum states of neutrons
We propose a method for observation of the quasi-stationary states of
neutrons, localized near the curved mirror surface. The bounding effective well
is formed by the centrifugal potential and the mirror Fermi-potential. This
phenomenon is an example of an exactly solvable "quantum bouncer" problem that
could be studied experimentally. It could provide a promising tool for studying
fundamental neutron-matter interactions, as well as quantum neutron optics and
surface physics effects. We develop formalism, which describes quantitatively
the neutron motion near the mirror surface. The effects of mirror roughness are
taken into account.Comment: 13 pages, 10 figure
Anomalous far infrared monochromatic transmission through a film of type-II superconductor in magnetic field
Anomalous far infrared monochromatic transmission through a lattice of
Abrikosov vortices in a type-II superconducting film is found and reported. The
transmitted frequency corresponds to the photonic mode localized by the defects
of the Abrokosov lattice. These defects are formed by extra vortices placed out
of the nodes of the ideal Abrokosov lattice. The extra vortices can be pinned
by crystal lattice defects of a superconductor. The corresponding frequency is
studied as a function of magnetic field and temperature in the framework of the
Dirac-type two-band model. While our approach is valid for all type-II
superconductors, the specific calculations have been performed for the
YBaCuO (YBCO). The control of the transmitted
frequency by varying magnetic field and/or temperature is analyzed. It is
suggested that found anomalously transmitted localized mode can be utilized in
the far infrared monochromatic filters.Comment: 9 pages, 2 figure
A Life-Cycle Analysis of the Greenhouse Gas Emissions of Corn-Based Ethanol
1. Introduction pg. 1
2. Review of the Scientific Papers, Technical Reports, Data Sets, and Other Information that have Become Available Since 2010 and Relate to Current Emissions Levels in Each Emissions Category pg. 9
3. Current GHG Emission Values for Each Emissions Source Category pg. 88
4. Projected GHG LCA Emissions Values for a Business-As-Usual Scenario and a Building-Blocks Scenario for Corn Ethanol in 2022 pg. 15
A Life-Cycle Analysis of the Greenhouse Gas Emissions of Corn-Based Ethanol
1. Introduction pg. 1
2. Review of the Scientific Papers, Technical Reports, Data Sets, and Other Information that have Become Available Since 2010 and Relate to Current Emissions Levels in Each Emissions Category pg. 9
3. Current GHG Emission Values for Each Emissions Source Category pg. 88
4. Projected GHG LCA Emissions Values for a Business-As-Usual Scenario and a Building-Blocks Scenario for Corn Ethanol in 2022 pg. 15
Localization of a 64-kDa phosphoprotein in the lumen between the outer and inner envelopes of pea chloroplasts
The identification and localization of a marker protein for the intermembrane space between the outer and inner chloroplast envelopes is described. This 64-kDa protein is very rapidly labeled by [γ-32P]ATP at very low (30 nM) ATP concentrations and the phosphoryl group exhibits a high turnover rate. It was possible to establish the presence of the 64-kDa protein in this plastid compartment by using different chloroplast envelope separation and isolation techniques. In addition comparison of labeling kinetics by intact and hypotonically lysed pea chloroplasts support the localization of the 64-kDa protein in the intermembrane space. The 64-kDa protein was present and could be labeled in mixed envelope membranes isolated from hypotonically lysed plastids. Mixed envelope membranes incorporated high amounts of 32P from [γ-32P]ATP into the 64-kDa protein, whereas separated outer and inner envelope membranes did not show significant phosphorylation of this protein. Water/Triton X-114 phase partitioning demonstrated that the 64-kDa protein is a hydrophilic polypeptide. These findings suggest that the 64-kDa protein is a soluble protein trapped in the space between the inner and outer envelope membranes. After sonication of mixed envelope membranes, the 64-kDa protein was no longer present in the membrane fraction, but could be found in the supernatant after a 110000 × g centrifugation
Atomic effects in astrophysical nuclear reactions
Two models are presented for the description of the electron screening
effects that appear in laboratory nuclear reactions at astrophysical energies.
The two-electron screening energy of the first model agrees very well with the
recent LUNA experimental result for the break-up reaction , which so far defies all available theoretical models.
Moreover, multi-electron effects that enhance laboratory reactions of the CNO
cycle and other advanced nuclear burning stages, are also studied by means of
the Thomas-Fermi model, deriving analytical formulae that establish a lower and
upper limit for the associated screening energy. The results of the second
model, which show a very satisfactory compatibility with the adiabatic
approximation ones, are expected to be particularly useful in future
experiments for a more accurate determination of the CNO astrophysical factors.Comment: 14 RevTex pages + 2 ps (revised) figures. Phys.Rev.C (in production
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