504 research outputs found
Nuclear matter and neutron matter for improved quark mass density- dependent model with mesons
A new improved quark mass density-dependent model including u, d quarks,
mesons, mesons and mesons is presented. Employing this
model, the properties of nuclear matter, neutron matter and neutron star are
studied. We find that it can describe above properties successfully. The
results given by the new improved quark mass density- dependent model and by
the quark meson coupling model are compared.Comment: 18 pages, 7 figure
Additive decomposability of functions over abelian groups
Abelian groups are classified by the existence of certain additive
decompositions of group-valued functions of several variables with arity gap 2.Comment: 17 page
Influence of build orientation on static and axial fatigue properties of maraging steel specimens produced by additive manufacturing
Abstract Additive manufacturing involves a layer-by-layer build-up of mechanical parts and it is a manufacturing technology that can be adopted with different engineering metal materials like steels, aluminium and titanium alloys. Aim of the present investigation is to analyse the influence of the build orientation on static and axial fatigue properties of maraging steel specimens manufactured by Direct Metal Laser Sintering (DMLS) of EOS metal powders. After manufacturing, some of the specimens were subjected to age hardening heat treatment (490 °C for 6 hours, followed by air cooling). Both heat treated and as-manufactured specimens have been built at 0° as well as at 90° orientation with respect to the specimen's axis. Analyses of the crack initiation point are performed in order to investigate the fatigue failure mechanisms. Finally, the fatigue strength of the additively manufactured specimens was compared with that exhibited by vacuum melted specimens of the same steel reported in literature
Effective hadron masses and couplings in nuclear matter and incompressibility
The role of effective hadron masses and effective couplings in nuclear matter
is studied using a generalized effective Lagrangian for sigma-omega model. A
simple relation among the effective masses, the effective couplings and the
incompressibility K is derived. Using the relation, it is found that the
effective repulsive and the effective attractive forces are almost canceled to
each other at the normal density. Inversely, if this cancellation is almost
complete, K should be 250-350MeV.Comment: 13 pages of text, 16 figure
Toxicity of statins on rat skeletal muscle mitochondria
Abstract.: We investigated mitochondrial toxicity of four lipophilic stains (cerivastatin, fluvastatin, atorvastatin, simvastatin) and one hydrophilic statin (pravastatin). In L6 cells (rat skeletal muscle cell line), the four lipophilic statins (100ÎŒmol/l) induced death in 27-49% of the cells. Pravastatin was not toxic up to 1mmol/l. Cerivastatin, fluvastatin and atorvastatin (100ÎŒmol/l) decreased the mitochondrial membrane potential by 49-65%, whereas simvastatin and pravastatin were less toxic. In isolated rat skeletal muscle mitochondria, all statins, except pravastatin, decreased glutamate-driven state 3 respiration and respiratory control ratio. Beta-oxidation was decreased by 88-96% in the presence of 100ÎŒmol/l of the lipophilic statins, but only at higher concentrations by pravastatin. Mitochondrial swelling, cytochrome c release and DNA fragmentation was induced in L6 cells by the four lipophilic statins, but not by pravastatin. Lipophilic statins impair the function of skeletal muscle mitochondria, whereas the hydrophilic pravastatin is significantly less toxi
Finite Nuclei in a Relativistic Mean-Field Model with Derivative Couplings
We study finite nuclei, at the mean-field level, using the Zimanyi-Moskowski
model and one of its variations (the ZM3 model). We calculate energy levels and
ground-state properties in nuclei where the mean-field approach is reliable.
The role played by the spin-orbit potential in sorting out mean-field model
descriptions is emphasized.Comment: 17 pages, 9 figures, 30 kbytes. Uses EPSF.TEX. To appear in Zeit. f.
Phys. A (Hadrons and Nuclei
A California Statewide Three-Dimensional Seismic Velocity Model from Both Absolute and Differential Times
We obtain a seismic velocity model of the California crust and uppermost mantle using a regional-scale double-difference tomography algorithm. We begin by using absolute arrival-time picks to solve for a coarse three-dimensional (3D) P velocity (V_P) model with a uniform 30 km horizontal node spacing, which we then use as the starting model for a finer-scale inversion using double-difference tomography applied to absolute and differential pick times. For computational reasons, we split the state into 5 subregions with a grid spacing of 10 to 20 km and assemble our final statewide V_P model by stitching together these local models. We also solve for a statewide S-wave model using S picks from both the Southern California Seismic Network and USArray, assuming a starting model based on the VP results and a V_P/V_S ratio of 1.732. Our new model has improved areal coverage compared with previous models, extending 570 km in the SWâNE direction and 1320 km in the NWâSE direction. It also extends to greater depth due to the inclusion of substantial data at large epicentral distances. Our V_P model generally agrees with previous separate regional models for northern and southern California, but we also observe some new features, such as high-velocity anomalies at shallow depths in the Klamath Mountains and Mount Shasta area, somewhat slow velocities in the northern Coast Ranges, and slow anomalies beneath the Sierra Nevada at midcrustal and greater depths. This model can be applied to a variety of regional-scale studies in California, such as developing a unified statewide earthquake location catalog and performing regional waveform modeling
Applying a three-dimensional velocity model, waveform cross correlation, and cluster analysis to locate southern California seismicity from 1981 to 2005
We compute high-precision earthquake locations using southern California pick and waveform data from 1981 to 2005. Our latest results are significantly improved compared to our previous catalog by the following: (1) We locate events with respect to a new crustal P and S velocity model using three-dimensional ray tracing, (2) we examine six more years of waveform data and compute cross-correlation results for many more pairs than our last analysis, and (3) we compute locations within similar event clusters using a new method that applies a robust fitting method to obtain the best locations satisfying all the differential time constraints from the waveform cross correlation. These results build on the relocated catalogs of Hauksson and Shearer (2005) and Shearer et al. (2005) and provide additional insight regarding the fine-scale fault structure in southern California and the relationship between the San Andreas Fault (SAF) and nearby seismicity. In particular, we present results for two regions in which the seismicity near the southern SAF seems to align on dipping faults
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