Institution
Universidad del Norte, Colombia
Education•Barranquilla, Colombia•
About: Universidad del Norte, Colombia is a education organization based out in Barranquilla, Colombia. It is known for research contribution in the topics: Population & Context (language use). The organization has 3562 authors who have published 4355 publications receiving 37861 citations. The organization is also known as: University of the North, Colombia & Uninorte.
Papers published on a yearly basis
Papers
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TL;DR: In this article, the authors studied the electronic properties of rippled freestanding graphene membranes under central load from a sharp tip and developed a gauge field theory on a honeycomb lattice valid beyond the continuum theory.
Abstract: We study the electronic properties of rippled freestanding graphene membranes under central load from a sharp tip. To that end, we develop a gauge field theory on a honeycomb lattice valid beyond the continuum theory. Based on the proper phase conjugation of the tight-binding pseudospin Hamiltonian, we develop a method to determine conditions under which continuum elasticity can be used to extract gauge fields from strain. Along the way, we resolve a recent controversy on the theory of strain engineering in graphene: There are no $K$-point-dependent gauge fields. We combine this lattice gauge field theory with atomistic calculations and find that for moderate load, the rippled graphene membranes conform to the extruding tip without a significant increase in elastic energy. Mechanical strain is created on a membrane only after a certain amount of load is exerted. In addition, we find that the deformation potential---even when partially screened---induces qualitative changes on the electronic spectra, with Landau levels giving way to equally spaced peaks.
61 citations
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TL;DR: In this article, the authors presented a parametric analysis of a combined power/cooling cycle, which combines the Rankine and absorption refrigeration cycles, uses ammonia-water mixture as the working fluid and produces power and refrigeration, while power is the primary goal.
Abstract: SUMMARY
This paper presents a parametric analysis of a combined power/cooling cycle, which combines the Rankine and absorption refrigeration cycles, uses ammonia–water mixture as the working fluid and produces power and refrigeration, while power is the primary goal. This cycle, also known as the Goswami Cycle, can be used as a bottoming cycle using waste heat from a conventional power cycle or as an independent cycle using low-temperature sources such as geothermal and solar energy. Optimum operating conditions were found for a range of ammonia concentration in the basic solution, isentropic turbine efficiency and boiler pressure. It is shown that the cycle can be optimized for net work, cooling output, effective first law and exergy efficiencies. The effect of rectification cooling source (external and internal) on the cycle output was investigated, and it was found that an internal rectification cooling source always produces higher efficiencies. When ammonia vapor is superheated after the rectification process, cycle efficiencies increase but cooling output decreases. Copyright © 2010 John Wiley & Sons, Ltd.
61 citations
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TL;DR: In this article, an analysis of the regression coefficients (a, b ) for the two periods showed a decrease in b and an increase in a after 1999, which coincides with a decrease of suspended sediment transport.
60 citations
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TL;DR: In this paper, the effects of different variables of child labor on academic performance are investigated, and the results show that the relationship between child labor and academic performance is based on the conflict between these two activities.
60 citations
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TL;DR: To assess clinical impact, psychological effects, and knowledge of pregnant women during the COVID‐19 outbreak in seven cities in Colombia, there are uncertainty and concerns about the maternal and fetal consequences of SARS‐CoV‐2 infection during pregnancy.
59 citations
Authors
Showing all 3594 results
Name | H-index | Papers | Citations |
---|---|---|---|
Sid E. O'Bryant | 41 | 168 | 8123 |
Francisco Rothhammer | 39 | 191 | 8247 |
Juan Carlos Niebles | 37 | 70 | 9751 |
Miguel A. Labrador | 36 | 193 | 5951 |
Alcides Chaux | 35 | 121 | 4795 |
Calogero M. Santoro | 30 | 157 | 3041 |
Toby Miller | 30 | 378 | 4694 |
Diego Viasus | 29 | 75 | 2069 |
Carlos Lizama | 28 | 183 | 2617 |
Robert Pitt | 28 | 234 | 4015 |
Camilo Montes | 28 | 74 | 2878 |
James Hall | 27 | 114 | 2785 |
Luis A. Cisternas | 26 | 154 | 2012 |
Antonio Rodríguez Andrés | 26 | 91 | 2151 |
Ana C. Fonseca | 26 | 120 | 2608 |