8,512 research outputs found
Development of Dose Conversion Coefficients for Radionuclides Produced in Spallation Neutron Sources
A research consortium comprised of representatives from several universities and national laboratories will be established as part of this project to generate internal and external dose conversion coefficients for radionuclides produced in spallation neutron sources. Information obtained from this multi-year study will be used to support the siting and licensing of future accelerator-driven nuclear initiatives within the U.S. Department of Energy complex, including the Spallation Neutron Source (SNS) and Accelerator Production of Tritium (APT) projects. Determination of these coefficients will also fill data gaps for several hundred radionuclides that exist in Federal Guidance Report (FGR) No. 11 and in Publications 68 and 72 of the International Commission on Radiological Protection (ICRP). This proposal discusses the overall research collaboration in general and the University of Nevada, Las Vegas (UNLV) funded portion of the research to be implemented by Phillip Patton and Mark Rudin in particular
A Study of Fiber Orientation in Machine Made Papers
The purpose of this thesis was to study fiber orientation in paper made on the pilot plant paper machine at Western Michigan University. The variables used in the study were fiber length and draw tensions. The shrinkage of the web was one dependent variable that was measured.
It was found that, on this paper machine, fiber orientation is independent of fiber length. Also, large draw tensions will increase the degree of orientation in the direction of the draw. And finally, increased draw tensions will result in an increase of MD elongation and CD shrinkage.
It is recommended here that further study be done in the area of refining and its affects on orientation
Symmetry enhanced first-order phase transition in a two-dimensional quantum magnet
Theoretical studies of quantum phase transitions have suggested critical points with higher symmetries than those of the underlying Hamiltonian. Here we demonstrate a surprising emergent symmetry of the coexistence state at a strongly discontinuous phase transition between two ordered ground states. We present a quantum Monte Carlo study of a two-dimensional S=1/2 quantum magnet hosting the antiferromagnetic (AFM) and plaquette-singlet solid (PSS) states recently detected in SrCu2(BO3)2. We observe that the O(3) symmetric AFM order and the Z2 symmetric PSS order form an O(4) vector at the transition. The control parameter g (a coupling ratio) rotates the vector between the AFM and PSS sectors and there are no energy barriers between the two at the transition point gc. This phenomenon may be observable in SrCu2(BO3)2.First author draf
Law for the Illinois farmer / 1079
"This circular replaces Circular 886."Cover title
A novel linear direct drive system for textile winding applications
The paper describes the specification, modelling, magnetic design, thermal characteristics and control of a novel, high acceleration (up to 82g) brushless PM linear actuator with Halbach array, for textile package winding applications. Experimental results demonstrate the realisation of the actuator and induced performance advantages afforded to the phase lead, closed-loop position control scheme
A Ground Water Quality Summary for Alaska: a Termination Report
The expanding economic activity throughout the State of Alaska
has created an urgent demand for water resource data. Ground water
quality information is of particular interest since this is the most
used source for domestic and industrial supplies.
Many agencies and individuals have accumulated large quantities
of data but their value has been marginal due to a lack of distribution
to potential users. It was the original intent of the work reported
herein to gather, collate, and publish all ground water quality data
available in the files of university, state, and federal laboratories.
Soon after the inception of the project the major contributor, the
U.S. Geological Survey, found it was administratively impossible to
contribute either the monies or the data necessary to accomplish the
ultimate goals of the project -- An Atlas on Alaskan Ground Water
Qualities.
At the time the above decision was made the Institute felt too
much information was on hand to allow it to lay fallow. Therefore,
this report was prepared, In a more limited scope than originally
planned, to fill the need for a readily available source of information.The work upon which this report is based was supported by
funds provided by the U.S. Department of the Interior, Office of
Water Resources Research, Project Number A-024-ALAS and Agreement
Number 14-01-0001-1070
Junior Faculty Engagement at iSchools: Personal Experience during the First Several Years
This roundtable discussion will explore how junior faculty at iSchools have been able to embed their research, teaching, and service activities within their schools, the larger institutions, and broader communities. The session will also focus on the ways in which junior faculty have received guidance in their roles--from the job search through the first several years in a tenure-track position. Roundtable leaders represent a variety of institutions and experiences--as faculty at the University of Illinois at Urbana-Champaign [WJM], the University of Maryland [SP], the University of North Carolina at Chapel Hill [PME], and the University of Texas at Austin [MW], and with doctoral-level preparation at the University of North Carolina at Chapel Hill [WJM, MW], the University of Toronto [SP], and the University of Washington [PME]. While the annual junior faculty mentoring event at the iConference specifically targets junior faculty as participants, this roundtable session offers a more inclusive environment for the discussion of this topic, specifically engaging doctoral students and senior faculty as well as their junior colleagues
Nonadiabatic extension of the Heisenberg model
The localized states within the Heisenberg model of magnetism should be
represented by best localized Wannier functions forming a unitary
transformation of the Bloch functions of the narrowest partly filled energy
bands in the metals. However, as a consequence of degeneracies between the
energy bands near the Fermi level, in any metal these Wannier functions cannot
be chosen symmetry-adapted to the complete paramagnetic group M^P. Therefore,
it is proposed to use Wannier functions with the reduced symmetry of a magnetic
subgroup M of M^P [case (a)] or spin dependent Wannier functions [case (b)].
The original Heisenberg model is reinterpreted in order to understand the
pronounced symmetry of these Wannier functions. While the original model
assumes that there is exactly one electron at each atom, the extended model
postulates that in narrow bands there are as many as possible atoms occupied by
exactly one electron. However, this state with the highest possible atomiclike
character cannot be described within the adiabatic (or Born-Oppenheimer)
approximation because in the (true) nonadiabatic system the electrons move on
localized orbitals that are still symmetric on the average of time, but not at
any moment. The nonadiabatic states have the same symmetry as the adiabatic
states and determine the commutation properties of the nonadiabatic Hamiltonian
H^n. The nonadiabatic Heisenberg model is a purely group- theoretical model
which interprets the commutation properties of H^n that are explicitly given in
this paper for the two important cases (a) and (b). There is evidence that the
occurrence of these two types of Wannier functions in the band structure of a
metal is connected with the occurrence of magnetism and superconductivity,
respectively
Changes in zebrafish (Danio rerio) lens crystallin content during development.
PurposeThe roles that crystallin proteins play during lens development are not well understood. Similarities in the adult crystallin composition of mammalian and zebrafish lenses have made the latter a valuable model for examining lens function. In this study, we describe the changing zebrafish lens proteome during development to identify ontogenetic shifts in crystallin expression that may provide insights into age-specific functions.MethodsTwo-dimensional gel electrophoresis and size exclusion chromatography were used to characterize the lens crystallin content of 4.5-day to 27-month-old zebrafish. Protein spots were identified with mass spectrometry and comparisons with previously published proteomic maps, and quantified with densitometry. Constituents of size exclusion chromatography elution peaks were identified with sodium dodecyl sulfate-polyacrylamide gel electrophoresis.ResultsZebrafish lens crystallins were expressed in three ontogenetic patterns, with some crystallins produced at relatively constant levels throughout development, others expressed primarily before 10 weeks of age (βB1-, βA1-, and γN2-crystallins), and a third group primarily after 10 weeks (α-, βB3-, and γS-crystallins). Alpha-crystallins comprised less than 1% of total lens protein in 4.5-day lenses and increased to less than 7% in adult lenses. The developmental period between 6 weeks and 4 months contained the most dramatic shifts in lens crystallin expression.ConclusionsThese data provide the first two-dimensional gel electrophoresis maps of the developing zebrafish lens, with quantification of changing crystallin abundance and visualization of post-translational modification. Results suggest that some crystallins may play stage specific roles during lens development. The low levels of zebrafish lens α-crystallin relative to mammals may be due to the high concentrations of γ-crystallins in this aquatic lens. Similarities with mammalian crystallin expression continue to support the use of the zebrafish as a model for lens crystallin function
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