Listar Ciencias Exactas y Naturales por título
Mostrando ítems 2887-2906 de 5964
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Low-dimensional magnetic properties of orthorhombic MnV2O6 : a nonstandard structure stabilized at high pressure
(2017) [Artículo de periódico] -
Low-dimensional phase-locked states in the zakharov equations
(1996) [Artículo de periódico]In this paper we identify phase-locked states among the solutions of the Zakharov equations. Locked states appear as resonant island chains in the appropriate Poincaré plots, with the relevant surface of section obtained ... -
Low energy consumption synthesis of nanostructured TiO2 particles by combining oxidant peroxide method and microwave-assisted hydrothermal treatment
(2016) [Artículo de periódico]Titanium dioxide with high specific surface area in the crystalline anatase phase is a promising material for environmental applications. In this work, TiO2 with good applicability for photocatalytic processes has been ... -
Low energy limit of the chern-simons theory coupled to fermions
(1997) [Artículo de periódico]We study the nonrelativistic limit of the theory of a quantum Chern-Simons field minimally coupled to Dirac fermions. To get the nonrelativistic effective Lagrangian one has to incorporate vacuum polarization and anomalous ... -
Low-extinction windows in the inner Galactic Bulge
(2002) [Artículo de periódico]We built K band extinction maps in the area of two candidate low-extinction windows in the inner Bulge: W0.2-2.1 at (l, b) = (0.25°, –2.15° ), and W359.4-3.1 at (l, b) = (359.40°, −3.10°). We employed JH Ks photometry from ... -
Low-frequency vibrations of soft colloidal glasses
(2010) [Artículo de periódico]We conduct experiments on two-dimensional packings of colloidal thermosensitive hydrogel particles whose packing fraction can be tuned above the jamming transition by varying the temperature. By measuring displacement ... -
Low-mass secondary-ion ejection from molecular solids by mev heavy ions : radial velocity distributions
(1996) [Artículo de periódico]Secondary ions sputtered in individual MeV ion impacts are analyzed in a high resolution time-of-flight mass spectrometer. The initial radial velocity distributions of low mass (up to m/z≈300 u) positive and negative ... -
Low-mass variable stars in the globular cluster NGC 6397
(2017) [Artículo de periódico]We have conducted a photometric survey of the globular cluster NGC 6397 in a search for variable stars. We obtained ∼11 h of time-resolved photometric images with one European Southern Observatory-Very Large Telescope using ... -
Low potential barrier height effects in magnetic tunneling junctions
(2007) [Artículo de periódico]This paper reports on the study of deposited (Ni81Fe19/AlOx /Co) magnetic tunnel junctions by magnetron sputtering, with the insulating layer obtained by plasma oxidation of Al. Concentration of the tunnel current in small ... -
Low signal-to-noise spectroscopy and surface photometry of two faint galaxies in the field of NGC 7479
(2003) [Artículo de periódico]We present low signal-to-noise spectroscopy and surface photometry of two small galaxies, detected in the field of the nearby asymmetric barred spiral NGC 7479, near a prolongation of the western arm that forms a faint ... -
Low temperature aging effects on the formation of Sn nanoclusters in SiO/sub 2/Si films and interfaces
(2007) [Artículo de periódico]The formation of Sn nanocrystals NCs in ion implanted SiO2 /Si films is investigated using Rutherford backscattering spectrometry and transmission electron microscopy. Low temperature and long time aging treatments followed ... -
Low-temperature ion-induced epitaxial growth of alfa-FeSi2 and cubic FeSi2 in Si
(1993) [Artículo de periódico]Ion-beam-induced epitaxial crystallization of amorphous Si implanted with Fe to 18 at. % peak concentration was studied. The structure of the specimen was characterized using transmission electron microscopy and Rutherford ... -
Low-temperature iron-nitride phase transformations induced by ion bombardment
(1996) [Artículo de periódico]We show that for the Fe–N system the combined use of ion irradiation and thermal annealing can lower the temperature for a given phase transformation. By Ar bombarding N-implanted Fe samples at 250 and 300 °C, we have ... -
Low temperature sensitivity CMOS transconductor based on GZTC MOSFET condition
(2016) [Artículo de periódico]Complementary Metal Oxide Semiconductor (CMOS) Transconductors, or Gm cells, are key building blocks to implement a large variety of analog circuits such as adjustable filters, multipliers, controlled oscillators and ... -
Low-voltage, low-area, nW-power CMOS digital-based biosignal amplifier
(2022) [Artículo de periódico]This paper presents the operation principle and the silicon characterization of a power efficient ultra-low voltage and ultra-low area fully-differential, digital-based Operational Transconductance Amplifier (OTA), suitable ... -
Ludwig Boltzmann e a arte de voar
(2006) [Artículo de periódico]Uma das facetas pouco conhecidas de Ludwig Boltzmann diz respeito a sua fascinação pela aviação. Em 1894, em uma palestra de muita repercussão, na qual fez voar pelo auditório uma réplica de uma aeronave, Boltzmann defendeu ... -
Luminous infrared galaxies. III. Multiple merger, extended massive star formation, galactic wind, and nuclear inflow in NGC 3256
(2000) [Artículo de periódico]We report detailed evidence for multiple merger, extended massive star formation, galactic wind, and circular/noncircular motions in the luminous infrared galaxy NGC 3256, based on observations of highresolution imaging ... -
Lung cancer : changes in histology, gender, and age over the last 30 years in Brazil
(2017) [Artículo de periódico]Objective: To describe the trends in tumor histology, gender and age among patients with non-small cell lung cancer (NSCLC) treated with lung resection. The histology of lung cancer has changed in developed countries, and ... -
A luta pela terra e a recriação dos espaços de vida de assentados na Campanha Gaúcha
(2013) [Artículo de periódico]A luta pelo acesso a terra no Brasil, organizada através de movimentos sociais, já é uma questão histórica e vem ganhando cada dia mais força. A conquista da terra para um assentado representa a construção de um “novo ... -
A luz do sol : um curso dirigido a crianças da regiao litorânea e a crianças veranistas
(1993) [Artículo de periódico]Resumo não disponível
