1,068 research outputs found
Daily Eastern News: April 09, 1974
https://thekeep.eiu.edu/den_1974_apr/1006/thumbnail.jp
Effect of Iodine Doping on BiSrCaCuO: Charge Transfer or Interlayer Coupling?
A comparative study has been made of iodine-intercalated
BiSrCaCuO single crystal and 1 atm O
annealed BiSrCaCuO single crystal using AC
susceptibility measurement, X-ray photoemission (XPS) and angle-resolved
ultraviolet photoemission spectroscopy (ARUPS). AC susceptibility measurement
indicates that O-doped samples studied have T of 84 K,
whereas T of Iodine-doped samples studied are 80 K. XPS Cu 2p core
level data establish that the hole concentration in the CuO planes are
essentially the same for these two kinds of samples. ARUPS measurements show
that electronic structure of the normal states near the Fermi level has been
strongly affected by iodine intercalation. We conclude that the dominant effect
of iodine doping is to alter the interlayer coupling.Comment: LBL 9 pages, APS_Revtex. 5 Figures, available upon request.
UW-Madison preprin
High-temperature ferromagnetism of electrons in narrow impurity bands: Application to CaB
Ferromagnetism with high Curie temperature , well above room
temperature, and very small saturation moment has been reported in various
carbon and boron systems. It is argued that the magnetization must be very
inhomogeneous with only a small fraction of the sample ferromagnetically
ordered. It is shown that a possible source of high within the
ferromagnetic regions is itinerant electrons occupying a narrow impurity band.
Correlation effects do not reduce the effective interaction which enters the
Stoner criterion in the same way as in a bulk band. It is also shown how, in
the impurity band case, spin wave excitations may not be effective in lowering
below its value given by Stoner theory. These ideas are applied to
CaB and a thorough review of the experimental situation in this material is
given. It is suggested that the intrinsic magnetism of the B and O
dimers might be exploited in suitable structures containing these elements.Comment: 26 pages, 2 figure
Disciplining Skepticism Through Kantâs Critique, Fichteâs Idealism, and Hegelâs Negations
This chapter considers the encounter of skepticism with the Kantian and post-Kantian philosophical enterprise and focuses on the intriguing feature whereby it is assimilated into this enterprise. In this period, skepticism becomes interchangeable with its other, which helps understand the proliferation of many kinds of views under its name and which forms the background for transforming skepticism into an anonymous, routine practice of raising objections and counter-objections to oneâs own view. German philosophers of this era counterpose skepticism to dogmatism and criticism, ancient to modern skepticism, and, importantly, conceptualize the transitions from one form to another, which forms the conceptual matrix in which new disciplinary forms, such as psychology, anthropology, and historicism contend for cultural-intellectual standing beside philosophy. I present this assimilationist trajectory by reviewing three well-known moments of this encounter of skepticism and idealism: (1) Kantâs idealization of skepticism as a floating position amidst various philosophical positions through the dialectic, polemics, systematics, and history of pure reason; (2) Fichteâs schematic conception of skepticism as a dispute of systems in the early Wissenschaftslehre following his review of the skeptic G. E. Schulzeâs attacks on Critical philosophy; (3) Hegelâs historicizing conception of skepticism in the context of differences between subjective idealism and speculative thought and his early Jena review of another work by the same skeptic Schulze
A Demonstration of using Partnerships and Private Lands Conservation to Evaluate Livestock Grazing as a Management Tool for Greater Sage Grouse in Central Montana
Partnerships across agencies and land ownerships established to maintain wildlife-compatible âworking landscapesâ are critical for conserving and managing wildlife in the West. Preliminary results from the first three years of a 10-yr study in central Montana demonstrate this management approach. We are evaluating prescribed grazing systems implemented by NRCSâs Sage Grouse Initiative (SGI) that are designed to improve hiding cover and food availability for Greater sage grouse (Centrocercus urophasianus) during critical life stages via voluntary, incentive-based modifications of livestock grazing management. Extensive vegetation sampling across 8 SGI-enrolled ranches and 20 non-enrolled ranches in 2013 revealed significant increases in residual grass height, live grass height, and herbaceous vegetation cover on SGI-enrolled lands. In 2011-2013, we monitored adult female sage-grouse and chicks with radiotelemetry to measure vital rates and habitat use. Annual hen survival ranged from 57-74 percent, nest success ranged from 12-61 percent, and chick survival ranged from 9-23 percent. Using an information theoretic approach in program MARK, the top-ranked nest success model showed that grass height was positively correlated with nest success.  During late nesting to early brood rearing periods of 2012 and 2013 we used pitfall traps to collected ground-dwelling arthropods from cattle grazed and rest-rotation phase pastures enrolled in the SGI program. Collected arthropods were identified and appropriate specimens were classified as sage grouse chick food items. During both years of study, food item catches were greatest (P < 0.03) in rested versus grazed pastures indicating that strategic pasture rest may increase the availability of sage grouse chick food resources
Foundations of Relational Particle Dynamics
Relational particle dynamics include the dynamics of pure shape and cases in
which absolute scale or absolute rotation are additionally meaningful. These
are interesting as regards the absolute versus relative motion debate as well
as discussion of conceptual issues connected with the problem of time in
quantum gravity. In spatial dimension 1 and 2 the relative configuration spaces
of shapes are n-spheres and complex projective spaces, from which knowledge I
construct natural mechanics on these spaces. I also show that these coincide
with Barbour's indirectly-constructed relational dynamics by performing a full
reduction on the latter. Then the identification of the configuration spaces as
n-spheres and complex projective spaces, for which spaces much mathematics is
available, significantly advances the understanding of Barbour's relational
theory in spatial dimensions 1 and 2. I also provide the parallel study of a
new theory for which positon and scale are purely relative but orientation is
absolute. The configuration space for this is an n-sphere regardless of the
spatial dimension, which renders this theory a more tractable arena for
investigation of implications of scale invariance than Barbour's theory itself.Comment: Minor typos corrected; references update
The relativistic Sagnac Effect: two derivations
The phase shift due to the Sagnac Effect, for relativistic matter and
electromagnetic beams, counter-propagating in a rotating interferometer, is
deduced using two different approaches. From one hand, we show that the
relativistic law of velocity addition leads to the well known Sagnac time
difference, which is the same independently of the physical nature of the
interfering beams, evidencing in this way the universality of the effect.
Another derivation is based on a formal analogy with the phase shift induced by
the magnetic potential for charged particles travelling in a region where a
constant vector potential is present: this is the so called Aharonov-Bohm
effect. Both derivations are carried out in a fully relativistic context, using
a suitable 1+3 splitting that allows us to recognize and define the space where
electromagnetic and matter waves propagate: this is an extended 3-space, which
we call "relative space". It is recognized as the only space having an actual
physical meaning from an operational point of view, and it is identified as the
'physical space of the rotating platform': the geometry of this space turns out
to be non Euclidean, according to Einstein's early intuition.Comment: 49 pages, LaTeX, 3 EPS figures. Revised (final) version, minor
corrections; to appear in "Relativity in Rotating Frames", ed. G. Rizzi and
M.L. Ruggiero, Kluwer Academic Publishers, Dordrecht, (2003). See also
http://digilander.libero.it/solciclo
Soft systems methodology: a context within a 50-year retrospective of OR/MS
Soft systems methodology (SSM) has been used in the practice of operations research and management science OR/MS) since the early 1970s. In the 1990s, it emerged as a viable academic discipline. Unfortunately, its proponents consider SSM and traditional systems thinking to be mutually exclusive. Despite the differences claimed by SSM proponents between the two, they have been complementary. An extensive sampling of the OR/MS literature over its entire lifetime demonstrates the richness with which the non-SSM literature has been addressing the very same issues as does SSM
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