TP3 MECANICA Modulo 5

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INGLÉS I – INGENIERÍA EN MECÀNICA 
3ª ACTIVIDAD DE PRÁCTICA ORIENTADORA – MÓDULOS 5 
 
 Lee el siguiente texto1. Luego resuelve en castellano las consignas a 
continuación. 
 
The True Amphipathic Nature of Graphene Flakes: A Versatile 
2D Stabilizer 
First published: 16 July 2020 
 
Since the experimental proof of its existence, graphene, a 2D carbon allotrope, has attracted a 
vast amount of research activity due to its unique electronic, mechanical, and thermal 
properties. This extraordinary material holds great promise for applications ranging from 
optoelectronic, through environmental to biomedical technologies. To efficiently manufacture 
graphene‐based devices, composites, coatings, or membranes, it is essential to understand 
graphene's properties and, for many applications, its interactions with adsorbates when it is 
placed in a liquid environment. 
 To date, nearly all studies focused on graphene oxide (GO) flakes or its derivatives obtained by 
subsequent reduction or further functionalization rather than on pure graphene flakes. This is 
primarily because pristine graphene is considered as difficult to disperse and individualize in 
solvents, melts, and matrices. However, graphene oxide flakes, which have no clearly defined 
structure, are not only difficult to process toxic, but also do not retain the fundamental 
properties of graphene. A recent study has also shown that graphene oxide cannot be 
considered as a true 2D stabilizer. The presence of additional stabilizing highly oxidized carbon 
material, the so‐called oxidative debris, adsorbed on the surface of the graphene oxide flake, is 
a prerequisite for graphene oxide flakes to stabilize an emulsion. Therefore, broader utilization 
of pristine graphene would have major advantages in terms of applications. 
Despite significant progress in the field in recent years, there is no consensus whether graphene 
flakes are typical hydrophobes or could, under certain conditions, become wettable. There is 
also much debate about which parameter plays a dominant role in tuning the hydrophobicity: 
lateral size, number of layers or a combination of specific surface area and thickness of flakes. 
Moreover, some studies even suggest that pristine graphene flakes are a new type of stabilizer 
 
 
 
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which can stabilize the oil/water emulsions without any additional agents enabling their 
assembly at the oil/water interface. Therefore, we have reinvestigated this question with precise 
experiments and rigorous theoretical studies. Here, we demonstrate the amphipathic nature of 
pristine graphene flakes and how to tune it by varying the flake size. In doing this, we explain all 
the reported inconsistencies in the literature. We discuss the underlying mechanism responsible 
for the stability of water/oil emulsions stabilized by pristine graphene flakes 
1) ¿Qué tipo de texto es? (1 punto) 
2) ¿Por qué el grafeno ha tenido mucha actividad en cuanto a investigación? (2 
puntos) 
 
3) ¿Cuáles podrían ser sus aplicaciones? (2 puntos) 
 
4) ¿Cómo se considera al grafeno pristino? (2 puntos) 
 
5) ¿Qué ha demostrado un estudio reciente sobre el grafeno? (2 puntos) 
 
6) Subraye en el texto 3 (tres) conectores lógicos que no sean “and” ni “but”. 
Sintetice las ideas que conectan, y luego indique la función de cada uno. (6 
puntos) 
 
a) 1ra idea: ………………………………………………………………………… 
…………………………………………………………………………………. 
2da idea: ………………………………………………………………………... 
………………………………………………………………………………….. 
Conector: ……………………….. Función: ………………………………… 
 
b) 1ra idea: ………………………………………………………………………… 
…………………………………………………………………………………. 
2da idea: ………………………………………………………………………... 
………………………………………………………………………………….. 
Conector: ………………………. Función: …………………………………. 
 
 
7) ¿A qué se refieren las siguientes palabras? (5 puntos) 
a) ITS (párrafo 1) 
b) ITS (párrafo 2) 
 
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c) WHICH (párrafo 2) 
d) WHICH (párrafo 3) 
e) IT (párrafo 3) 
 
 
8) Traslade al castellano los siguientes bloques nominales: (8 puntos) 
a) a vast amount of research activity 
b) unique electronic, mechanical, and thermal properties. 
c) The presence of additional stabilizing highly oxidized carbon material 
d) a combination of specific surface area and thickness of flakes. 
 
 
 
 
28 puntos en total. Para aprobar el TP, el/la estudiante deberá alcanzar un mínimo de 17 puntos