Search results for " graph"

Electrochemical detection of dopamine with negligible interference from ascorbic and uric acid by means of reduced graphene oxide and metals-NPs base…

2021

Abstract Dopamine is an important neurotransmitter involved in many human biological processes as well as in different neurodegenerative diseases. Monitoring the concentration of dopamine in biological fluids, i.e., blood and urine is an effective way of accelerating the early diagnosis of these types of diseases. Electrochemical sensors are an ideal choice for real-time screening of dopamine as they can achieve fast, portable inexpensive and accurate measurements. In this work, we present electrochemical dopamine sensors based on reduced graphene oxide coupled with Au or Pt nanoparticles. Sensors were developed by co-electrodeposition onto a flexible substrate, and a systematic investigati…

Cue combination in a combined feature contrast detection and figure identification task

2006

AbstractTarget figures defined by feature contrast in spatial frequency, orientation or both cues had to be detected in Gabor random fields and their shape had to be identified in a dual task paradigm. Performance improved with increasing feature contrast and was strongly correlated among both tasks. Subjects performed significantly better with combined cues than with single cues. The improvement due to cue summation was stronger than predicted by the assumption of independent feature specific mechanisms, and increased with the performance level achieved with single cues until it was limited by ceiling effects. Further, cue summation was also strongly correlated among tasks: when there was …

A novel approach to prevent graphene oxide re-aggregation during the melt compounding with polymers

2015

Abstract The technology for the preparation of polymer-GO nanocomposites was investigated by studying the structure-properties relationships of two different systems, based on PA6 and EVA, fabricated by using different preparation methods, i.e. melt mixing, wet phase inversion, and the combination of the two. The morphology of nanocomposites resulted dramatically influenced by the technique adopted and showed to be the critical variable affecting the physical properties of the materials. Finally, the mechanical and dynamic-mechanical of the nanocomposites were improved by using the hybrid technique combining the two procedures.

Assessing forest landscape structure using geographic windows.

2001

Landscape structure, interpreted as indicator of functional processes, has become a main attribute of multiresource forest inventories, enhancing its value with respect to society needs. This approach implies effective use of earth observation techniques and geographic information systems to obtain a global view of the inventoried landscapes and to understand the ecological functions of large spatially-heterogeneous landscape mosaics. Landscape structure often reveal extremely complex patterns that can only be very roughly characterized by methods of Euclidean geometry. Conversely, fractals can be applied to adequately describe many of the irregular, fragmented patterns found in nature. In …

Diseño gráfico para formar al profesorado de primaria

2021

Educar en diseño es probablemente la base para una predisposición social hacia la creatividad y la innovación. Presentamos los resultados de una investigación desarrollada en la práctica universitaria, formulada metodológicamente como estudio de caso. Incorporamos la práctica del diseño gráfico al currículum formativo de Maestro/a en Educación Primaria. Si queremos que la ciudadanía aprecie el diseño, conviene preparar al profesorado. Para lograr este acercamiento al diseño gráfico planteamos un taller en el que cada participante elabora su propio exlibris. Los resultados positivos nos animan a continuar con este tipo de iniciativas que aglutinan diseño, patrimonio, identidad e inclusión. E…

Basic variables in reflection-impulsivity: A training programme to increase reflectivity

1993

We found that reflective children in our study had better academic qualifications than impulsive ones. We worked with a sample of 201 Spanish children in their last year of Primary School. We elaborated and applied an intervention programme to increase reflectivity. The results were excellent and showed consistency and stability, which is very unusual in the context of R-I research. There was no significant difference between boys and girls’ performance on MFF20. The children were 12, 13 and 14 year olds and we found a reflection increase at 13 but not at 14. Contrary to the opinion of Salkind and Nelson on this point concerning MFFT, we believe that MFF20 is adequate for these ages. The Sp…

A method of variation of boundaries for waveguide grating couplers

2008

We describe a method for calculating the solution of the electromagnetic field in a non-rectilinear open waveguide by using a series expansion, starting from the field of a rectilinear waveguide. Our approach is based on a method of variation of boundaries. We prove that the obtained series expansion converges and we provide a radiation condition at infinity in such a way that the problem has a unique solution. Our approach can model several kinds of optical devices which are used in optical integrated circuits. Numerical examples will be shown for the case of finite aperiodic waveguide grating couplers.

Titelbild: Electron Transfer in a Supramolecular Associate of a Fullerene Fragment (Angew. Chem. 8/2014)

2014

Cover Picture: Electron Transfer in a Supramolecular Associate of a Fullerene Fragment (Angew. Chem. Int. Ed. 8/2014)

2014

Adiabatic versus Non-Adiabatic Electron Transfer at 2D Electrode Materials

2021

<div><div><div><p>Outer-sphere electron transfer (OS-ET) is a cornerstone elementary electrochemical reaction, yet microscopic understanding is largely based on idealized theories, developed in isolation from experiments that themselves are often close to the kinetic (diffusion) limit. Focusing on graphene as-grown on a copper substrate as a model 2D material/metal-supported electrode system, this study resolves the key electronic interactions in OS-ET, and identifies the role of graphene in modulating the electronic properties of the electrode/electrolyte interface. An integrated experimental-theoretical approach combining co-located multi-microscopy, centered on sc…