Estudo experimental e teórico das propriedades magnéticas e supercondutoras dos compostos borocarbetos da série Y(Ni 1-x Mn x) 2 B2 C com x = 0,0, 0,01, 0,025, 0,05, 0,10 e 0,15

Apresentamos neste trabalho os resultados de um estudo experimental e teórico dos compostos borocarbetos supercondutores da série Y(Ni1-xMnx)2B2C com x = 0; 0,01; 0,025; 0,05; 0,10; 0,15. A principal motivação para este trabalho foi investigar a estrutura eletrônica e a possível formação do momento magnético sobre os átomos de impureza de Mn nos compostos Y(Ni1- xMnx)2B2C. O aparecimento do momento magnético localizado no sítio da impureza possibilitou estudar a influência do Mn sobre o mecanismo de quebra de pares supercondutores e sobre as propriedades magnéticas do composto. Os borocarbetos são compostos de estrutura cristalina tetragonal de corpo centrado e altamente anisotrópicos (c/a~3). São intermetálicos de alta temperatura crítica supercondutora Tc, com forte acoplamento elétron-fonon. Em alguns casos podem apresentar ordem magnética, supercondutividade e também coexistência ou competição energética entre ambos. As medidas de transporte eletrônico, em função da temperatura, foram feitas utilizando-se um detector síncroton baseado na técnica de quatro pontos operando na faixa de 4,2K até 300K. Essas medidas possibilitaram o estudo das propriedades relacionadas ao transporte eletrônico na fase supercondutora. Na fase normal, extraiu-se a dependência em energia da função espectral de fonons α² F (ω) para alguns compostos da série estudada. As medidas magnéticas em função da temperatura e do campo magnético foram feitas utilizando-se um SQUID (Superconducting Quantun Interference Device – Quantun Design Model MPMS XL). Tais medidas permitiram a caracterização das propriedades magnéticas de nossas amostras. Em particular determinou-se o valor, em regime de saturação, do momento magnético associado ao sítio cristalino do Mn. Foram determinadas também as correntes críticas supercondutoras usando o Modelo de estado crítico de Bean e a variação da temperatura crítica supercondutora (Tc) com a mudança do campo externo aplicado. As medidas magnéticas permitiram a obtenção do diagrama que relaciona o campo crítico inferior (HC1) e a temperatura, variando-se a concentração do átomo dopante de manganês. Foi feito um esforço teórico no sentido de interpretar os resultados experimentais. Para isso foram usados três modelos: O modelo de estado crítico de Bean já citado acima e um modelo baseado na fórmula de Ziman usando uma aproximação para a função espectral de fonons para descrever a resistividade no regime de alta temperatura. Além disto, usou-se o modelo de duas sub-redes para a descrição do momento magnético das impurezas de Mn, em função da concentração, na série Y(Ni ) ( 2 ω α F 1-xMnx)2B2C.

Comparação da razão carga/deflexão entre fios ortodônticos de Ni-Ti termoativados 0,014”x0,025” e 0,016”x0,022”

The knowledge of the mechanical properties of nickel-titanium (NiTi) termoactives of the more accessible of the domestic market is still limited. Given this, the objective of this study was to evaluate and compare through deflection tests in brackets NiTi wires 03 term rectangular gauge 0.014 '' enabled x 0.025 '' and 0.016 '' x 0.022 '' of different brands (MORELLI (R), ORMCO (R) ORTHOSOURCE (R), ORTHOMETRIC (R), EURODONTO (R) and ADITEK (R)). All tests were carried out on universal testing machine EMIC DL 2000 under identical conditions and controlled at a temperature of 36 degrees C +/- 0.5 degrees C. Five measurements (N= 5) were performed for each thickness/wire tag that was deflected up to a limit of 4.0mm at a speed of 1.0mm/min. Each 0.2mm (round trip) of corresponding strength measured deflection for the construction of the graph of force x deflection at Tesc program version 3.04. Each graphic was evaluated according to the following variables: beginning of the Martensitic transformation (cN and mm), maximum strength (cN), the beginning and end of the plateau of deactivation (cN and mm) and length (mm) plateau. The average and standard deviation were calculated for all variables and statistical analysis was made by ANOVA tests 2 criteria and Turkey or Kruskal-Wallis and Dunn, a 5% level of significance. The results showed that the tests of 0.014 '' x0.025 '' ORTHOMETRIC (R) brands and ORMCO (R) showed the best results, as well as the wires of the MORELLI (R) and ORTHOSOURCE (R) to wires 0.016 '' x0.022 ''. In General, the gauge wires 0.014 '' x0.025 '' showed strength levels on the plateau of deactivation to 6 x smaller than 0.016 '' x0.022 '' caliber.

Hampton McNeely Jarrell Papers - Accession 343

The Hampton McNeely Jarrell Papers consists of Dr. Jarrell’s professional activities, membership in organizations, and work as a Winthrop faculty member, and includes biographical data, correspondence, teaching materials, rough notes, and drafts of his published and unpublished books, journal articles, newspaper articles, speeches, research notes, and several maps of South Carolina during the Revolutionary and Civil Wars, relating to Jarrell’s publishing efforts, his activities as a Winthrop College faculty member, and his work with various historical, literary, and educational organizations as well as the history of the Jarrell Family Plantation. Research subjects include Rock Hill, S.C.; Col. William Hill; the Revolutionary War; the Civil War; Wade Hampton; William Gilmore Simms; York County, S.C.; and South Carolina history.

Na 50 Nachlass Arthur Schopenhauer - 'Schopenhauer-Archiv', 343 - Anmerkungen an Professor Hugo von Meltzl zum Baufortschritt des Schopenhauer-Denkmals

u.a.: Schopenhauer Denkmal; Anti-Schopenhauerismus; Ferdinand Laban; Arthur Schopenhauer;

Ms.Ff.F.Stoltze 3. 343 - Brief von Friedrich Stoltze an ... Fries

Sturmschäden am Haus und im Garten

Laboratory shearing experiments at low sliding velocities of IODP Hole 343-C0019E

The 2011 Tohoku-Oki earthquake demonstrated that the shallowest reaches of plate boundary subduction megathrusts can host substantial coseismic slip that generates large and destructive tsunamis, contrary to the common assumption that the frictional properties of unconsolidated clay-rich sediments at depths less than View the MathML source should inhibit rupture. We report on laboratory shearing experiments at low sliding velocities (View the MathML source) using borehole samples recovered during IODP Expedition 343 (JFAST), spanning the plate-boundary décollement within the region of large coseismic slip during the Tohoku earthquake. We show that at sub-seismic slip rates the fault is weak (sliding friction µs=0.2-0.26), in contrast to the much stronger wall rocks (µs>~0.5). The fault is weak due to elevated smectite clay content and is frictionally similar to a pelagic clay layer of similar composition. The higher cohesion of intact wall rock samples coupled with their higher amorphous silica content suggests that the wall rock is stronger due to diagenetic cementation and low clay content. Our measurements also show that the strongly developed in-situ fabric in the fault zone does not contribute to its frictional weakness, but does lead to a near-cohesionless fault zone, which may facilitate rupture propagation by reducing shear strength and surface energy at the tip of the rupture front. We suggest that the shallow rupture and large coseismic slip during the 2011 Tohoku earthquake was facilitated by a weak and cohesionless fault combined with strong wall rocks that drive localized deformation within a narrow zone.

Composition of suspended matter and bottom sediments from the Atlantic Ocean and its seas

The book summarizes data on distribution and composition of sedimentary material suspended in waters of the Atlantic Ocean and its seas. Results of observations of Soviet and foreign expeditions are given. Distribution of suspended matter in sections across the ocean, as well as in the most studied seas are shown. New data on grain size, mineral and chemical composition of suspended matter are published. Summary of history of investigation of bottom sediments from the Atlantic Ocean from the first scientific cruises to the present is done. A brief description of sediment types in the ocean and a detailed description of Mediterranean Sea sediments are given.