4,702 research outputs found
The reconstruction of a subclass of domino tilings from two projections
AbstractWe present a new way of studying the classical and still unsolved problem of the reconstruction of a domino tiling from its row and column projections. After giving a simple greedy strategy for solving the problem from one projection, we introduce the concept of degree of a domino tiling. We generalize an algorithm for the reconstruction of domino tilings of degree two from two projections, to domino tilings of degree three and four
Monitoramento da extração de areia nos municÃpios não pertencentes ao Zoneamento Ambiental Minerário do trecho paulista da várzea do rio ParaÃba do Sul.
Remote sensing techniques can significantly contribute to environmental monitoring of the low cost mineral extraction of sand pits. This study aims to evaluate the increase of sand pits mining activity between the period of 2004 to 2009, in municipalities of the Paraiba do Sul basin of São Paulo State, Brazil, that are not included in the mineral zoning of this basin. Visual interpretation of Landsat-5 (Thematic Mapper ? TM sensor) images indicated areas of sand extraction for the municipalities of Aparecida, Cachoeira Paulista and Roseira with an annual average increase of 10.1 ha, 20.5 ha and 33.5 ha, respectively. The municipality with the highest percentage of sand mining area increase was Lorena (233%). Results presented in this study can be used to justify the mineral zoning expansion to these municipalities
Heptaphyrins: expanded porphyrins with seven heterocyclic rings
Expanded porphyrins containing seven pyrrole/heterocyclic rings linked in a cyclic fashion are termed heptaphyrins. The number of π-electrons in heptaphyrins depends on the number ofmeso carbon bridges used to link the heterocyclic rings, accordingly heptaphyrins with 28π-electrons and 30π-electrons are reported to date. Both condensation reactions of the appropriate precursors and acid-catalysed oxidative coupling reactions have been utilized to synthesise the heptaphyrins. The 30π heptaphyrins exhibit rich structural diversity where some of the heterocyclic rings in the macrocycle undergo a 180° ring flipping. An overview of the synthetic methods employed for the synthesis of heptaphyrins, their spectroscopic properties, structural behaviour and aromatic properties are highlighted in this paper
Core modified oxybenziporphyrins: new aromatic ligands for metalcarbon bond activation
Successful syntheses of two new aromatic core modified oxybenziporphyrins by a simple 3 + 1 methodology and the first aromatic core modified oxybenziporphyrin palladium complex are reported
10 ps timing with highly irradiated 3D trench silicon pixel sensors
In this paper the results of a beam test characterization campaign of 3D
trench silicon pixel sensors are presented. A time resolution in the order of
10 ps was measured both for non-irradiated and irradiated sensors up to a
fluence of . This feature and a
detection efficiency close to make this sensors one of the best
candidates for 4D tracking detectors in High-Energy-Physics experiments.Comment: Prepared for submission to JINST, IWORID 202
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