in the global village we have spoken several times of nanotechnology and its future applications. In the near future potential applications for nanotechnology are truly amazing. However, today I would like to discuss nanotechnology in a less known but is the more necessary today: energy.
Our society is based on a percentage too high in oil and its derivatives, a limited resource that sooner or later end up exhausted. This leads to the next stage of technological development: The energy problem. One of the great challenges facing humanity: to find a clean, cheap and self-sufficient.
When we think of energy, always thought big: large turbines, large power plants, large dams, large tankers ... However, we see that there are other possible ways to the energy problem: Nanotechnology could be one of them!
Nanotechnology: potential energy and environmental solution
particular focus
3 basic materials of the nanotechnology, linked not only to organic processes but intended to reduce environmental problems:
1. Carbon nanotubes
define a nanotube as tubular structures with a diameter of nanometer order.
Carbon nanotubes are an allotrope of carbon, like diamond, graphite or fullerenes. Its structure can be seen from a graphite sheet rolled on itself. Depending on the degree of curl (flexibility), and how original the film is formed, the result can lead to nanotubes with different diameters and internal geometry.
researcher Sumio Iijima, who discovered carbon nanotubes in 1991-which is why it has been awarded the Prince of Asturias Award of Science and Technology 2008 - noted that nanotechnology may help develop more efficient devices that can consume between 10 and 20 times less than current equipment, ie, saving between 90% and 95 %, which will result in a large decrease in emissions of carbon dioxide discharged into the atmosphere. Below
give an application of interest in carbon nanotubes:
adsorbents
As carbon nanotubes have high surface area, pore structure and layered is ideal for storing various items and chemicals.
Recent studies nanotubes have been adsorbents: nicotine and tar in cigarette smoke, reactive dyes, volatile organic compounds (n-pentane, n-hexane, n-heptane, n-octane, n-cyclohexane, benzene, trichlorethylene), microcystins, divalent metal ions and water Trihalomethanes (CHCl3, CHBrCl2, CHBr2Cl and CHBr3).
Removal of heavy metals: Among the toxic metal ion adsorbents (activated carbon, zeolite, bio-resins, among others) researchers are interested in carbon nanotubes due to their high adsorption capacity. In studies, nanotubes have shown great potential in adsorption, its future applications projected in the care of the environment in removing toxic ions from the process wastewater industriales.14
To improve the efficiency of adsorption, the nanotubes are subjected to prior oxidation. The oxidation was done with solutions of various chemical agents such as KMnO4, HNO3, NaOCl, HCl, H2SO4, O3 or H2O2, they increase the number of functional groups containing oxygen (C = O, COOH, OH) and an increasing burden surface negative. The oxygen atoms increase the ion exchange capacity.
uses carbon nanotubes
2. Nanosponges: sustainable development alternative
When more than 30 years ago the economist Fritz Schumacher coined the phrase "small is beautiful", it was with the hope of boosting the "intermediate technologies", which use skills, knowledge and local materials, rather than high-tech solutions to solve the problems of the poor.
However, in recent times the phrase has acquired a different meaning, as scientists and engineers began to develop nanotechnology - processes that control matter at the atomic or molecular scale - and showed that this field can also promote the development sustainable.
In nanotechnology, there is no area more promising than the water treatment. Nanofiltration techniques and nanoparticles can reduce or eliminate pollutants and contribute to achieving Millennium Development Goal Key: halving the number of people without sustainable access to safe drinking water by 2015.
nanosponges development that absorb water and trap impurities stands as an example of how you might solve the problems of water purification by means of nanotechnology in countries like South Africa, if they overcome the difficulties associated with testing and marketing.
There are those who are similar to frames; others, countless cups of tea, each has just one billionth of a meter wide. But when it comes to name them, do not hesitate to call nanosponges.
This topic should be of interest to the Peruvian authorities and why not all countries, since it is cutting edge biotechnology, easy to apply and very economical.
The idea is that you can fasten with clamps to a water source, is the kitchen faucet or pipe that carries liquid to a power plant, and they absorb the fluid, trapping the impurities in a multitude of tiny cavities , while letting the pure water.
course, South Africa hopes to resolve their problems nanosponges to purify water where conventional treatments are insufficient, from clean water to all people to decontaminate the cooling systems to prevent rotting plant turbines. However, we still do not know for sure if nanosponges fulfill their promise, both technically and economically, they still have shortcomings, and its production is expensive.
A great utility of sponges is clean up spills, and there is great interest in manufacturing microscopic structures that have the ability to selectively absorb certain substances. A group of researchers just published in Nature Nanotechnology a technique for making nanosponges (structures of a size about one millionth of a millimeter). The procedure involves coating a tangled structure of manganese oxide nanowires with a layer of silicone to make it hydrophobic, ie water-repellent.
These sponges are sheets whose microstructure in the form of nanowires is able to absorb oils (up to twenty times its own weight), separating the water through a combination of capillarity and superhydrophobic. The material can be regenerated and reused for many cycles, and apparently the large-scale preparation is quite feasible.
is no doubt that one of the possible applications has to do with cleaning up oil spills and the like. Could be useful in the separation of mixtures of solvents, due to its selectivity.
3. Photosystem 1: natural energetic
cell
Plants generally possess the quality to capture solar energy through a series of pigments that comprise the photosystem 1, if we think a little key to new energy sources speaking at the nanoscale have all those molecules that comprise the photosystem 1 by an extraction of these and a manipulation of its components through nanotechnology could have new energy resources more efficient, less polluting, we benefit not only economically but also in terms of environmental preservation, then give the operating mechanism of photosystem 1 (solar energy collection): How
captured the light energy?
The light energy is captured by photosynthetic pigments located in the thylakoid membrane of chloroplasts. When a photon impact on photosynthetic pigment, an electron moves to a higher energy level. The pigment excited state can return to its original three ways:
- Losing extra energy as light and heat (fluorescence).
- Using a resonance energy transfer, in which the power (but not the electron) moves from one pigment to another.
- by oxidation of the pigment, the loss of high-energy electron that is captured by an electron carrier.
The most important photosynthetic pigment chlorophyll, which absorbs violet, blue and red and reflects green.
All photosynthetic pigments are grouped into photosystems, hypothetically, we can imagine the shape of a funnel. Can be of two types: photosystem I (maximum absorption 700 nm) and photosystem II (with an absorption maximum 680 nm).
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