14 resultados para Argon-36
em Brock University, Canada
Resumo:
Polycrysttdline samples of NaiCoOa were prepared using the "Rapid heat-up" method. One set of samples was annealed in flowing O2, while the other set in flowing Argon. X-Ray diffraction measurements indicated a stable phase of Nao.7Co02 mixed with C03O4 for all the samples even though they differed in concentration of Na. Argon annealed samples were insulators, whereas the ones annealed in O2 were metallic. Most of the measurements were performed on the sample Nao.7Co02, because it is the host compound for the superconductor sample Nao.35Co02-H20. Magnetization measurement showed that the magnetic moment decreased with increasing sodium concentration. This is due to the existence of C03O4 in samples with Na^ 0.7. As sodium concentration decreases, the magnetic moment increases due to the increasing concentration of C03O4 and its large magnetic moment. Magnetization measurements showed that the magnetic moment of Nao.7Co02 is field-dependent in low fields eind field-independent in fields higher than 100 G. Resistivity changes with temperature (dp/dT) increased with increasing Na concentration. Also resistivity measurements were performed under different hydrostatic pressures on Nao.7Co02. Two transitions were observed; one at a temperature Ti ~20 K and the other at T2 ^280 K, the transition at Ti has a magnetic origin and the one at T2 is a structiural transition. It was noticed that pressure aJfects resistivity of the sample. At higher pressures resistivity changes faster with temperature. Magnetoresistance measurement showed a small change in the resistivity, especially at lower temperatures. A novel layered superconductor Nao.35Co02H20 was prepared using de-intercalation of Na from the host compound Nao.7Co02. FVom the temperature dependence of the magnetization, the superconducting transition temperature and lower critictil field have been estimated as Tc=4.12 K and Hci=66 G, respectively.
Resumo:
Volumes of interest were published between 1812 and 1815 with articles about the War of 1812.
Resumo:
Volumes of interest were published between 1812 and 1815 with articles about the War of 1812. Issue for June 26, 1812 includes a proclamation issued by President James Madison confirming the Congress declaration of war against Great Britain.
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Dark brown sediment with areas of darker organic material. The clasts range from small to medium in size and angular to sub-rounded in shape. Lineations were abundant in this sample along with some rotation structures and common structures. A few grain stacks were also present.
Resumo:
Brown sediment with clasts ranging from small to large. Clast shape ranges from angular to sub-rounded. The sample is dominated with a sandy matrix. Some lineations can be seen throughout the sample. Rotation structures can also be seen in minor amounts.
Resumo:
License no. 144 of season 1872/73 made out to S.D. Woodruff for 36 square miles in berth no. 192. This document is slightly torn and stained along the right hand side. This does not affect the text, April 7, 1873.
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License no. 67 of season 1873/74 made out to S.D. Woodruff for 36 square miles in berth no. 192, June 13, 1873
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License no. 5 of season 1875/76 made out to S.D. Woodruff for 36 square miles in berth no. 192, June 1, 1875.
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License no. 2 of season 1886/87 made out to S.D. Woodruff for 36 square miles in berth no. 192, May 15, 1876.
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License no. 6 of season 1877/78 made out to S.D. Woodruff for 36 square miles in berth no.192, May 31, 1877.
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License no. 87 of season 1879/80 made out to S.D. Woodruff for 36 square miles in berth no. 192, June 3, 1879.
Resumo:
License no. 26 of season 1880/81 made out to S.D. Woodruff for 36 square miles in berth no. 192, May 27, 1880.
Resumo:
Pay roll voucher #36 from the Engineer Department of the Welland Railway for the Northern Division for the month of October, Nov. 3, 1857.
