Heat waves in 2-D Graphine : Future of electronics

Heat is something which makes us the sense of hotness or coolness of an object, heat is not as simple as it seems, but could you emagine that heat will be used for transmitting or receiving signals in the future electronic devices, at present we use electric signal for this purpose.
In a study published in Nature Communications, a team of EPFL researchers has shed new light on the mechanisms of thermal conductivity in graphene and other two-dimensional materials. They have demonstrated that heat propagates in the form of a wave, just like sound in air. This was up to now a very obscure phenomenon observed in few cases at temperatures close to the absolute zero. Traditionally heat can transfer via three modes conduction, convection and radiation. Radiation is the way by which heat transfer like waves but is solids the method governing heat transfer is conduction, but it is a great achievement that the phenomenon of heat through waves in graphine was achieved.
Generally in 3-d materials the heat transfers through the vibration called of atoms know as "phonons" that transfer energy to each other by the process of conduction and in this process it is not possible to transmit heat to long distance without losses. But the 2-d graphine can transmitt the heat in a reversible manner with the help of heart waves that suffer very less loss with the help the phenomenon of wave-like diffusion, called "second sound". In that case, all phonons march together in unison over very long distances. "Our simulations, based on first-principles physics, have shown that atomically thin sheets of materials behave, even at room temperature, in the same way as three-dimensional materials at extremely low temperatures" said the author of the study. He also says that not only graphine shows waves propagation property but various other elements are there which can show the similar results, which are yet to be tested.
This research will help the scientists and engineers which are keen to have a boom in the electronics technology replacing the Silicon.

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Sodium ion battery the future of electronic devices power supply

Lithium-ion batteries are the backbone of mostly all the electronic devices may it be your Android, iPhone, laptops or any other device the Li-ion batteries have served so well that in future there may be shortage of Lithium for the production of batteries if we are not able to get an alternative source of power.

Sodium could be used as an alternative for Lithium in the future batteries as it cheap, abundant and easily available but there lies some problems with sodium(Na) that the battery with Na-ion takes longer time to charge and it's discharge is so slow that it could not power high potential devices,but researchers led by Yong Lei, a professor at the Technical University of Ilmenau in Germany, have achieved a significant improvement in this area. The research claims that it has achieved the highest efficiency from a Na-ion battery which could challenge any Lithium battery in terms of charge and discharge.

To solve this problem there was a need to know the basics difference in reactions of both Na and Li. Sodium electronic configuration ends with 3s¹ whereas for Lithium it is 2s² which tells that both these metals can loose electrons which is required for a battery to operate but the size of sodium is larger so it is quite tough for Na ions to get absorbed or released by the electrods. However the size of sodium remains the same only the size of electrode was changed by molecule design strategy of pi-conjugated system, which basically involves manipulating the way that these molecules bond with each other. Physically, this strategy results in a terrace morphology, consisting of multiple, widely spaced layers that form a faster route for the sodium ions to move through. The extended π-conjugated system also improves the charge transport and stabilizes the charged and discharged states so that they can better tolerate the fast insertion/extraction of Na ions.

In terms of battery performance, this change results in significant improvements. As always, there is still a tradeoff between charge/discharge rates and capacity. But the new Na-ion batteries can operate at a current density (a measure of the charge/discharge rate) that is 1000 times higher (10 A/g vs. 10 mA/g) than most previously reported organic Na-ion batteries while retaining a much higher capacity (72 mAh/g).
At an intermediate current density (1 A/g), the new battery delivers an impressive reversible capacity of 160 mAh/g, which is one of the highest values reported for both organic Na-ion and Li-ion batteries to date. The battery also exhibits good capacity retention (70% retention after 400 cycles).

The scientists says that a lot of improvement has to be done to make this technology comes to your pocket but you have to wait for quiet some time.

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Dual nature of light filmed for the first time

Light is the only thing which makes everything visible and is the first thing which was formed after the big bang and knowing it better would ultimately lead to a science full future. Einstein was one of the first person to tell the world that light behaves in both nature that is wave and particle, since then a lot of studies have been done in the nature of light, even a branch of science quantum mechanics get its origination from this idea of light and it tells us that light can behave as both wave and particles at the same time but were are not able get the proof that this is possible simultaneously.

There were many occasions where light was photographed behaving like particle or like waves but for the first time a team at the Swiss Federal Institute of Technology in Lausanne (EPFL) has demonstrated an experiment which has captured the images of light behaving like waves and particles simultaneously.
The experiment is set up like this: A pulse of laser light is fired at a tiny metallic nanowire. The laser adds energy to the charged particles in the nanowire, causing them to vibrate. Light travels along this tiny wire in two possible directions, like cars on a highway. When waves traveling in opposite directions meet each other they form a new wave that looks like it is standing in place. Here, this standing wave becomes the source of light for the experiment, radiating around the nanowire.

This is where the experiment’s trick comes in: The scientists shot a stream of electrons close to the nanowire, using them to image the standing wave of light. As the electrons interacted with the confined light on the nanowire, they either sped up or slowed down. Using the ultrafast microscope to image the position where this change in speed occurred, which acts as a fingerprint of the wave-nature of light.

Experiment set up 

While this phenomenon shows the wave-like nature of light, it simultaneously demonstrates its particle aspect as well. As the electrons pass close to the standing wave of light, they “hit” the light’s particles, the photons. As mentioned above, this affects their speed, making them move faster or slower. This change in speed appears as an exchange of energy “packets” (quanta) between electrons and photons. The very occurrence of these energy packets shows that the light on the nanowire behaves as a particle.

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Artificial Photosynthesis :Future of fuels

Sun is the ultimate source of power if only for a day is all energy produced is stored it could fulfill the energy need of Earth for at least a thousand year. Sunlight is used for generating energy through the solar panels and the efficiency is almost 10% but it takes large numbers of solar panels for generating large amount of energy. Though photosynthesis may seems as a reverse process of using suns energy and converting it into glucose and oxygen, but this is the ultimate technique of getting sun energy into useful work. Plants do it all the time they convert sunlight into energy rich molecules with just carbondioxide, water and sunlight and of we are able to produce such a machine which could produce artificial photosynthesis then it would be a source of power with unlimited energy.

We are very close of generating such a device but the challenges lies in the process of oxidation of water and reduction of CO2, a research from Monash University has been able to recreate the photosynthesis process to produce methanol which is a fuel which can be used directly,and the efficiency of this process is higher than the natural photosynthesis. Various catalyst of copper dioxide are used for the oxidation of water and the reduction of carbondioxide and when the catalyst are coupled with materials that can absorb light fuels like methanol can be produced. If we are able to know the path followed by the process to occur and Researchers from institutions including Lund University have taken a step closer to producing solar fuel using artificial photosynthesis. In a new study, they have successfully tracked the electrons’ rapid transit through a light-converting molecule. The technique used is much difficult than the traditional solar panels but if we master this this will open a new corridors for energy which will be long lasting.

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Powerful Poop

A bus service started in the UK last year transporting 10000 persons per month from the Bristol airport to the city of bath but the thing which draws our attention is that the bus is powered by poop(human waste) for fuel, the city have enough people that there will be no shortage of fuel ever, the bus can travel a distance of 186 miles with the annual poop of just 5 people. Nasa is planning to go one step further, it is trying to get the fuel used for rockets which will be a great step in space industry as the fuel is a major challenge which stops us from covering large distances in space. I can assure you that today only you have flushed a tremendous source of power which could help the world in overcoming is power problems. As the technology grows our rate of power consumption is increasing rapidly and there is shortage of fuels like gasoline, diesel, natural gas etc, but there is one source that will last till the humans will last and it is your poop. An average person produces 360 pounds of poop in an year and if it is treated and used it could be enough to meet the basic power requirements of an individual. The food which we eat contains energy but all is not utilised by our body and is rejected in form of poop and this can be used again to extract the energy. A lot of technologies are working in this field and some have developed method of converting poop into energy which could be used as heat or work.

In India people uses cow dung as a source of fuel for the past 20 years or more where the dung is transported to a closed pit where it is allowed to degedrade which produces methane gas which is used for daily household work like cooking, heating, electricity etc. The same could be done from human poop but you need to forget about it while using it for cooking or heating. There are various companies like Black Gold Biofuel which process and converts poop into solid fuel which could be used to replace coal as a source of power. The Bioengineers at Oregon State University (OSU) have developed a microbial fuel cell that can treat waste water — and generate significant amounts of electricity at the same time. Consider what amount of energy can we produce of all the poop of 7 billion people can be used, wouldn't that be so stinky.

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