6,657 research outputs found
Saran film is fire-retardant in oxygen atmosphere
Saran was tested for flammability as a wrapping on TFE-insulated electrical wire bundles in oxygen gas at pressures of 7.5 psia and 14.7 psia. It was found to be fire retardant or self-extinguishing in most instances
Sites of Biosynthesis of Outer and Inner Membrane Proteins of Neurospora crassa Mitochondria
Outer and inner membranes of Neurospora crassa mitochondria were separated by the combined swelling, shrinking, sonication procedure. Membranes were characterized by electron microscopy and by marker enzyme activities. A red carotenoid pigment was found to be concentrated in the outer membrane. The inner mitochondrial membrane was resolved into about 20 protein bands on polyacrylamide gel electrophoresis, whereas the outer membrane shows essentially one single protein band. Only negligible incorporation of radioactive amino acids occurs into outer membrane when isolated mitochondria are synthesizing polypeptide chains. In agreement with this observation labeling of outer membrane protein is almost entirely blocked, when whole Neurospora cells are incubated with radioactive amino acids in the presence of cycloheximide, an inhibitor of cytoplasmic protein synthesis. Finally, the essential electrophoretic protein band from outer membrane does not become labeled when mitochondria are incubated with radioactive amino acids either in vitro or in vivo in the presence of cycloheximide. It is concluded that the vast majority, if not all, of the outer membrane protein is synthesized by the cytoplasmic system and that polypeptide chains formed by the mitochondrial ribosomes are integrated into the inner mitochondrial membrane
Efficient tight-binding Monte Carlo structural sampling of complex materials
While recent work towards the development of tight-binding and ab-initio
algorithms has focused on molecular dynamics, Monte Carlo methods can often
lead to better results with relatively little effort. We present here a
multi-step Monte Carlo algorithm that makes use of the possibility of quickly
evaluating local energies. For the thermalization of a 1000-atom configuration
of {\it a}-Si, this algorithm gains about an order of magnitude in speed over
standard molecular dynamics. The algorithm can easily be ported to a wide range
of materials and can be dynamically optimized for a maximum efficiency.Comment: 5 pages including 3 postscript figure
The 198Au beta-half-life in the metal Au revisited
The half-life of the beta-decay of 198Au has been measured for room
temperature and 12 K. The resulting values of T(RT) = 2.684 +- 0.004 d and T(12
K) = 2.687 +- 0.005 d agree well within statistical uncertainties. An evidence
for a temperature dependence of the half-life was not observed.Comment: accepted for publication in Eur. Phys. J.
Analysis of magnetization and a spin state crossover in the multiferroic CaCoMnO
Ca_3Co_{2-x}Mn_xO_6 (x ~ 0.96) is a multiferroic with spin-chains of
alternating Co(2+) and Mn(4+) ions. The spin state of Co(2+) remains
unresolved, due to a discrepancy between high temperature X-ray absorption
(S=3/2) and low temperature neutron (S=1/2) measurements. Using a combination
of magnetic modeling and crystal-field analysis, we show that the existing low
temperature data cannot be reconciled within a high spin scenario by invoking
spin-orbit or Jahn-Teller distortions. To unify the experimental results, we
propose a spin-state crossover with specific experimental predictions.Comment: 4 pages, 3 figure
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Visual Encoding of Dissimilarity Data via Topology-Preserving Map Deformation
We present an efficient technique for topology-preserving map deformation and apply it to the visualization of dissimilarity data in a geographic context. Map deformation techniques such as value-by-area cartograms are well studied. However, using deformation to highlight (dis)similarity between locations on a map in terms of their underlying data attributes is novel. We also identify an alternative way to represent dissimilarities on a map through the use of visual overlays. These overlays are complementary to deformation techniques and enable us to assess the quality of the deformation as well as to explore the design space of blending the two methods. Finally, we demonstrate how these techniques can be useful in several—quite different—applied contexts: travel-time visualization, social demographics research and understanding energy flowing in a wide-area power-grid
Factors Affecting Poultry Meat Yields
It has been 10 years since the previous publication bearing this title was issued. A quote from that publication, “…research reported 10 or more years ago is of questionable value because of the rapid progress made by the poultry industry…”, indicates that an updated review is now necessary. Information in that publication is not repeated here. The earlier report is still of much value, especially as it pertains to methodology and guidelines for comparing yield data. Although many of the same frustrations persist, in that all conditions of the research reported are not spelled out in the original articles and in many cases insufficient numbers were used to apply the results to commercial conditions, yet the authors here quoted are, in great measure, to be commended for progress in this regard. The NCM-46 Regional Technical Committee surveyed the literature available on the subject; the number of papers originated by members of the committee represents a major proportion of the reports reviewed
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