6,430 research outputs found
Film holder for curved vacuum platen
Vacuum apparatus for holding photographic film of various widths against cylindrically curved patens is discussed. Construction details and method of operation are explained. Illustration of equipment is provided
Alignment microscope for rotating laser scanner
Microscopic assembly for alignment of rotary laser focuses on small film area along scan line at oblique angle. Suitable choice of angle and location of optical components project laser beam line as X coordinate reticle. Coordination with horizontal recticle line included microscope facilitates Y coordinate position indexing
Rydberg states of hydrogen-like ions in braneworld
It has been argued that precise measurements of optical transition
frequencies between Rydberg states of hydrogen-like ions could be used to
obtain an improved value of the Rydberg constant and even to test Quantum
Electrodynamics (QED) theory more accurately, by avoiding the uncertainties
about the proton radius. Motivated by this perspective, we investigate the
influence of the gravitational interaction on the energy levels of
Hydrogen-like ions in Rydberg states within the context of the braneworld
models. As it is known, in this scenario, the gravitational interaction is
amplified in short distances. We show that, for Rydberg states, the main
contribution for the gravitational potential energy does not come from the rest
energy concentrated on the nucleus but from the energy of the electromagnetic
field created by its electrical charge, which is spread in space. The reason is
connected to the fact that, when the ion is in a Rydberg state with high
angular momentum, the gravitational potential energy is not computable in
zero-width brane approximation due to the gravitational influence of the
electrovacuum in which the lepton is moving. Considering a thick brane
scenario, we calculate the gravitational potential energy associated to the
nucleus charge in terms of the confinement parameter of the electric field in
the brane. We show that the gravitational effects on the energy levels of a
Rydberg state can be amplified by the extra dimensions even when the
compactification scale of the hidden dimensions is shorter than the Bohr
radius
Combinatorial formulation of Ising model revisited
In 1952, Kac and Ward developed a combinatorial formulation for the two
dimensional Ising model which is another method of obtaining Onsager's formula
for the free energy per site in the thermodynamic limit of the model. Feynman
gave an important contribution to this formulation conjecturing a crucial
mathematical relation which completed Kac and Ward ideas. In this paper, the
method of Kac, Ward and Feynman for the free field Ising model in two
dimensions is reviewed in a selfcontained way.Comment: 27 pages, 17 figure
Indexing film with a fluidic sensor
Fluidic sensor is used to measure passage of film without mechanical contact with counting device. Same sensor system may be used for different sizes of film. System has two fluidic sensors and operates on principle of electrically recording interruptions in air stream
Beyond the Shackles and Chains of the Middle Passage: Human Trafficking Unveiled (Comment)
This Comment analyzes the Trafficking Victims Protection Act by exploring the act's failures and successes. Part II looks at factors contributing to the rise of human trafficking. Part III provides a critical analysis of the TVPA, its purposes, and its shortcomings. Finally, Part IV proposes amendments that may aid law enforcement in protecting victims, as well as prosecuting traffickers. Reform must identify areas in the United States where trafficking activities are concentrated and move adequate resources, such as law enforcement training and mental health services for victims, to these areas. Second, funding for combating human trafficking should be reallocated from efforts abroad to law enforcement at home. American officials are better equipped to effectively utilize those resources for the benefit of trafficking victims. Finally, the TVPA must better provide ongoing mental health assistance to victims before, during, and after the traffickers have been prosecuted. This will better enable victims to aid law enforcement in finding and prosecuting traffickers, and will prevent survivors from being re-victimized in the future
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