grafeno

¿Qué es el grafeno?

-El grafeno es es una alotropía del carbono; la cual consiste en un teselado hexagonal plano (como un panal de abeja) formado por átomos de carbono y enlaces covalentes que se formarían a partir de la superposición de los híbridos sp² de los carbonos enlazados.

 ¿Cuáles son sus principales características? 

• Algunos científicos de la Universidad de Ilinois en Míchigan aseguran que el grafeno tiene propiedades de autoenfriamiento.

• Alta conductividad térmica y eléctrica.⁴

• Alta elasticidad y dureza.

• Resistencia (200 veces mayor que la del acero).⁵

• El grafeno puede reaccionar químicamente con otras sustancias para formar compuestos con diferentes propiedades, lo que dota a este material de gran potencial de desarrollo.

• Soporta la radiación ionizante.

• Es muy ligero, como la fibra de carbono, pero más flexible.

• Menor efecto Joule; se calienta menos al conducir los electrones.

• Consume menos electricidad para una misma tarea que el silicio.

• Genera electricidad al ser alcanzado por la luz.⁶

¿Qué aplicaciones se te ocurren?

-Múltiples aplicaciones, la mayoría de ellas en el campo de la electrónica (recubrimiento de pantallas táctiles, almacenamiento de energía y datos, pantallas táctiles flexibles y enrollables..), hasta la "simpleza" de ser usado como material aislante o en la tecnología.

ACTIVITIES OF MARCO POLO

-Who was Marco Polo?
 It was a Venetian merchant travelers of the Republic of Venice whose travels were recorded in Il Milione, a book that did much to introduce Europe to Central Asia and China. He learned the trade while his father and uncle, Niccolo and Maffeo, traveled to Asia and met Kublai Khan apparently. In 1269, they returned to Venice to meet with Mark for the first time.The three embark on an epic journey to Asia, returning after 24 years to find Venice at war with Genoa, Marco was imprisoned, and dictated his stories to a cellmate. He was released in 1299, became a wealthy merchant, married and had three children. He died in 1324, and was buried in San Lorenzo.

-What historical period is the text? 
The historical period is in the Middle Ages

- What do you know about this period?
 One class period was divided and at this time people discovered many things about science and the new way to get comfortable, as well as different types of heating systems. For example: coal. After coal, using wood to keep warm.

-What does the text area to discuss?
 The region was Cathay.

- What is it called today? 
Cathay is the Anglicized version of "Cathay" and an alternate name for China in English.

-Compare the development of this technology with the West during this period.

The Middle Ages coincided with the Islamic Golden Age. In this period there were many inventions and at that time, Islamic philosophy, science and technology were more advanced than in Western Europe. The period saw major technological advances, including the invention of cannon, spectacles, and artesian wells, and cross-cultural introduction of gunpowder, silk, the compass and the astrolabe from the east, so that in the Middle Ages in eastern Europe are more technological development in the western part.

-Why do you think the book was given this title?
 In my opinion, the book "Book of Wonders" was given this title because inside of this, you can find stories about new sources for energy production in the period the author of the book was wonderful and fantastic, because it was the beginning of the uses of energy so that was not well known and that people feel surprised.

-What stones do you think the text is talking about?
 I think the text speaks of coal, because it says something about the black stones found in nature and is highly flammable.

-What are the advantages and rock properties in the text? 
The properties and advantages are that these stones are extracted from the mountains, and shining, so that the flames as the firewood: completely consumed like coal. They maintain a fire and produce heat for cooking better than wood. And if you make a fire at night and ensure such catches, will stay on all night, right until the morning.

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