17,403 research outputs found
Japanese activities in refrigeration technology
Recent activities in refrigeration technology in Japan are discussed. Stirling cycle refrigerators and magnetic refrigerators are discussed. The development of units for use on trains is discussed
The X-ray Structure of A399 and A401: A Pre-Merging Cluster Pair
We present {\em ASCA} results of the pair clusters A399 and A401. The region
between the two clusters exhibits excess X-rays over the value expected with a
simple superposition of the two clusters. We see, however, no temperature rise
at the merging front; the temperature is near the average of those in the inner
regions of the two clusters. These indicate that the two clusters are really
interacting but it is not strong at present.
The inner regions of the two clusters show no radial variations of
temperature, abundance and absorption values. We set upper-limits of mass
deposition rate of cooling flow to be and
for A399 and A401, respectively. A hint of
azimuthal variation of the temperature is also found.Comment: 17 pages, 13 postscript figures, 2 external tables, accepted for
publication in PAS
Unique representation d=4k(k^2-1) in D(4)-quadruples {k-2,k+2,4k,d}
Let k â„ 3 be an integer. We show that if d is a positive integer such that the product of any two distinct elements of the set
{k-2,k+2,4k,d} increased by 4 is a square, then d must be
4k(k^2-1)
Time-dependent, species-specific effects of N:P stoichiometry on grassland plant growth
N and P have different eutrophication effects on grassland communities, yet the underlying mechanisms are poorly understood. To examine plant growth in response to the varying (relative) supply of N and P, we conducted a two-year greenhouse experiment. Five grasses and three herbs were grown with three N:P supply ratios at two overall nutrient supply levels. During the first year the plant growth was relatively low at both high and low N:P supply ratios, whereas during the second year the growth was especially low at a high N:P supply ratio. This second-year low growth was attributed to the high root death rate, which was influenced by a high N:P supply ratio rather than by the nutrient supply level. Species responded differently, especially in P uptake and loss at a high N:P supply ratio. Each species seemed to have a different strategy for P limitation, e.g. an efficient P uptake or a high P resorption rate. Species typical of P-limited grasslands had neither better P uptake nor better P retention at a high N:P supply ratio. This study quantitatively demonstrates an increased plant root death triggered by strong P limitation. This finding indicates a possible extra effect of N eutrophication on ecosystem functioning via changed N:P stoichiometr
The Variation of Gas Mass Distribution in Galaxy Clusters: Effects of Preheating and Shocks
We investigate the origin of the variation of the gas mass fraction in the
core of galaxy clusters, which was indicated by our work on the X-ray
fundamental plane. The adopted model supposes that the gas distribution
characterized by the slope parameter is related to the preheated temperature.
Comparison with observations of relatively hot (~> 3 keV) and low redshift
clusters suggests that the preheated temperature is about 0.5-2 keV, which is
higher than expected from the conventional galactic wind model and possibly
suggests the need for additional heating such as quasars or gravitational
heating on the largest scales at high redshift. The dispersion of the preheated
temperature may be attributed to the gravitational heating in subclusters. We
calculate the central gas fraction of a cluster from the gas distribution,
assuming that the global gas mass fraction is constant within a virial radius
at the time of the cluster collapse. We find that the central gas density thus
calculated is in good agreement with the observed one, which suggests that the
variation of gas mass fraction in cluster cores appears to be explained by
breaking the self-similarity in clusters due to preheated gas. We also find
that this model does not change major conclusions on the fundamental plane and
its cosmological implications obtained in previous papers, which strongly
suggests that not only for the dark halo but also for the intracluster gas the
core structure preserves information about the cluster formation.Comment: 17 pages, to be published in Ap
Klinische Untersuchungen ĂŒber die Resorptionskraft aus dem Subcutis
Nach Donath u. Tanne haben wir die Resorptionszeit des Uranins aus dem Subcutis bei verschiedenartigen Kranken untersucht. Unter den Resultaten sind die folgenden hervorzuheben; bei Morbus Basedowi, Kreislaufinsuffizienzien, hydropischen Nephritiden, Beriberi, Leberkrankheiten, Pleuritiden, bes. bei frischen FÀllen und schweren Tuberkulosen wurde die Resorption mehr oder weniger erheblich verlangsamt. Bei Ankylostomiaden war sie bald unverÀndert, bald eher verlangsamt, bes. verlangsamt bei denen mit hochgradiger AnÀmie. Bei Pleuritiden war es verschieden je nach den Krankheitsstadien, da sie z. B. bei frischen, zur Exsudation neigenden FÀllen verlangsam war, wÀhrend sie mit der Krankheitsbesserung zusammen immer schneller wurde und bei veralteten, mit Schwartenbildung oder mit immer gröber werdenden Reiben behafteten FÀllen sogar fast normal war.
FĂŒr den Ausfall dieser Probe spielt nicht nur der Zustand des Kreislaufes, wie die Blutströmungsgeschwindigkeit und die Blutdruckamplitude etc, wie Donath u. Tanne annahm, eine gewisse Rolle, sondern auch der Gewebszustand, dieser sogar eher grössere Rolle
Synchrotron X-ray diffraction study of a charge stripe order in 1/8-doped LaBaSrCuO
Lattice distortions associated with charge stripe order in 1/8 hole-doped
LaBaSrCuO are studied using synchrotron X-ray
diffraction for and . The propagation wave vector and charge
order correlation lengths are determined with a high accuracy, revealing that
the oblique charge stripes in orthorhombic crystal are more
disordered than the aligned stripes in tetragonal crystal. The twofold
periodicity of lattice modulations along the c-axis is explained by long-range
Coulomb interactions between holes on neighboring CuO planes.Comment: 4pages, 4figures, Submitted to PR
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