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At least 163 records · Page 9

Lattice Distortion, Polaron Conduction, and Jahn-Teller Effect on teh Magnetoresistance of La(sub 0.7)Ca(sub 0.5)CoO(sub 3) Epitaxial Films

In summary, we have investigated the role of lattice distortion, polaron conduction and Jahn-Teller coupling in the occurrence of the colossal negative magnetoresistance in perovskite oxides. We conclude that larger lattice distortion gives rise to larger zero-field resistivity and larger magnitude of negative magnetoresistance.

colossal negative magnetoresistance CMR lattice di↗

Strain Effects on the Structural and Magnetic Properties of La- Ca-Mn-O Epitaxial Films

La0.7Ca0.3MnO3 (a = 3.86 angstroms) epitaxial thin films have been grown on SrTiO3 (a = 3.905 angstroms), LaAlO3 (a = 3.79 angstroms), and YAlO3 (a/square root of 2 = 3.66 angstroms, b/square root of 2 = 3.77 angstroms) substrates. The films were analyzed with x-ray diffraction, x-ray photoemission spectroscopy, dc and ac resistivity, and dc magnetization.

epitaxial films lanthanum↗

Standards for Analysis of Ce, La, Pb, Rb, Se, Sr, Y, AND Zr in Rock Samples Using Laser-induced Breakdown Spectroscopy and X-ray Fluorescence

Analytical geochemistry has long depended on the availability of robust suites of rock standards with well-characterized compositions. Standard rock powders for wet chemistry and x-ray fluorescence were initially characterized and supplied to the community by the U.S. Geological Survey, which continues to distribute a few dozen standards. Many other rock standards have subsequently been developed by organizations such as the Centre de Recherches Pétrographiques et Géochimiques (CRPG) and Brammer Standard Company, Inc.

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