112,161 research outputs found
A new semimagnetic compound: Cd1-xFexIn 2S4 single crystal grown by CVT
No full textSingle crystals of the Cd1-xFexIn2S 4 compounds were grown by the chemical vapour transport method using iodine as transport agent. The crystals were grown by placing the ampoule in a two zone furnace, keeping the source temperature and the deposition temperature at 850 and 800 °C respectively. The resulting crystals with nominal concentrations: x = 0.25, 0.5, 0.75 were characterized by X-ray powder diffraction, electron probe micro-analysis and magnetic measurements. Electron probe micro-analysis showed that the actual concentration of Fe was lower than the nominal one. X-ray diffractograms were taken at room temperature for each sample, revealing that the compounds form a solid solution in the whole range of compositions and crystallize with cubic symmetry in the space group Fd3m. All samples show a spinel structure with a random arrangement of cations. The magnetic behavior of the samples was investigated by low-field magnetization measurements in the range 5-300 K. The observed magnetic behavior does not show any magnetic transition in the studied temperature range. However an irreversibility has been observed between zero-field-cooled (ZFC) and field-cooled (FC) cycles. High temperature susceptibility data follow the Curie-Weiss law with a negative paramagnetic Curie temperature, indicating the predominance of antiferromagnetic interactions. The optical absorption data for sample with x = 0.75 shows a direct energy gap of 1.28 eV at RT. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Synthesis and Characterization of Co-Doped ZnO Nanocompound
No full textZn1-xCoxO (x = 5%) nanopowders were prepared by using the autocombustion technique, and the structural, optical and magnetic properties were investigated. X-ray diffraction measurements show that the synthesized samples have a wurtzite structure. The formation of the wurtzite structure in Co doped ZnO nanoparticles was further confirmed by Fourier transform infra-red spectrometry. Optical absorption spectra show that the band energy of Zn0.95Co0.05O powders is about 2.42 eV at room temperature. Magnetic data obtained from as grown powders indicate the presence of antiferromagnetic interactions between particles
author-bios-SRD-19-0063.R1 – Supplemental material for The Network Structure of Police Misconduct
No full textSupplemental material, author-bios-SRD-19-0063.R1 for The Network Structure of Police Misconduct by George Wood, Daria Roithmayr and Andrew V. Papachristos in Socius</p
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
A new semimagnetic compound: Cd1-xFexIn2S4 single crystal grown by CVT
No full textSingle crystals of the Cd1-xFexIn2S4 compounds were grown by the chemical vapour transport method using
iodine as transport agent. The crystals were grown by placing the ampoule in a two zone furnace, keeping the
source temperature and the deposition temperature at 850 and 800 °C respectively. The resulting crystals with
nominal concentrations: x = 0.25, 0.5, 0.75 were characterized by X-ray powder diffraction, electron probe
micro-analysis and magnetic measurements. Electron probe micro-analysis showed that the actual
concentration of Fe was lower than the nominal one. X-ray diffractograms were taken at room temperature for
each sample, revealing that the compounds form a solid solution in the whole range of compositions and
crystallize with cubic symmetry in the space group Fd3m. All samples show a spinel structure with a random
arrangement of cations. The magnetic behavior of the samples was investigated by low-field magnetization
measurements in the range 5-300 K. The observed magnetic behavior does not show any magnetic transition
in the studied temperature range. However an irreversibility has been observed between zero-field-cooled
(ZFC) and field-cooled (FC) cycles. High temperature susceptibility data follow the Curie-Weiss law with a
negative paramagnetic Curie temperature, indicating the predominance of antiferromagnetic interactions. The
optical absorption data for sample with x = 0.75 shows a direct energy gap of 1.28 eV at RT
Variations on the Author
No full text“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Nanocrystals of Ni doped ZnO semiconductor by Sol-Gel combustion method
No full textNanoparticles of the system Zn0.95Ni0.05O were prepared by sol gel self- combustion method and a study of their structural, optical andmagnetic properties were conducted. X-ray diffraction study shows a hexagonal wurtzite structure for the nanocompound. The formation ofthe wurtzite structure in Ni doped ZnO was further confirmed by Fourier transform infra-red spectrometry. Transmission electron microscopyrevealed an average size of 31 nm for the particles. Optical absorption spectra shows that the band energy of Zn0.95Ni0.05O powders is about2.54 eV at room temperature. A study of the magnetic properties of the nanopowders of ZnO: Ni, reveals paramagnetic behavior, withinteraction ferromagnetic between particles.Fil: Carrero Lobo, Aneely Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Los Andes; VenezuelaFil: Sagredo, V.. Universidad de Los Andes; VenezuelaFil: Larionova, J.. Université Montpellier II; Franci
Description and phylogenetic relationships of a new trans-Andean species of Elachistocleis Parker 1927 (Amphibia, Anura, Microhylidae)
No full textSánchez-Nivicela, Juan C., Peloso, Pedro L. V., Urgiles, Verónica L., Yánez-Muñoz, Mario H., Sagredo, Yerka, Páez, Nadia, Ron, Santiago (2020): Description and phylogenetic relationships of a new trans-Andean species of Elachistocleis Parker 1927 (Amphibia, Anura, Microhylidae). Zootaxa 4779 (3): 323-340, DOI: 10.11646/zootaxa.4779.3.
Magnetic ordering of Mn2GeS4 single crystals with olivine structure
No full textSingle crystals of Mn2GeS4 were grown by chemical vapor transport. X-ray powder diffraction data show a single phase. Rietveld refinement results indicated that Mn2GeS4 crystalize in an olivine-type structure. The magnetic properties of the compound have been studied by means of DC magnetometry and AC susceptibility measurements. The system shows two different phase transitions on decreasing temperature, a first one at about 90 K, leading the system from the paramagnetic to an antiferromagnetic state and a second at about 25 K, corresponding to the onset of a weak ferromagnetic behavior superimposed to the underlying antiferromagnetic order. No evidence of a possible spin-glass behavior in the intermediate temperature region has been found
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