sábado, 23 de febrero de 2019

These Artificial Leaves Can Absorb 10 Times More CO2 From The Air Than Real Leaves

Plants possess a natural ability to purify the air and produce energy while doing so. The ability is called photosynthesis and it is the process whereby plants use water and carbon dioxide from the air to produce carbohydrates using energy from the sun. Scientists have found a way to make this happen artificially. The thing is, they hadn’t been able to get these artificial leaves to work outside the lab because the lab leaves use pure, pressurized carbon dioxide from tanks, which is different than getting it out of the air.

An artificial, bio-inspired leaf. Carbon dioxide (red and black balls) enter the leaf as water (white and red balls) evaporates from the bottom of the leaf. An artificial photosystem (purple circle at the center of the leaf) made of a light absorber coated with catalysts converts carbon dioxide to carbon monoxide and converts water to oxygen (shown as double red balls) using sunlight.” (Image: Meenesh Singh).
But now, researchers from the University of Illinois at Chicago have proposed a design solution that could change everything. Their idea just might be the leaves’ ticket out of the lab and into the environment. Their findings are reported in the journal ACS Sustainable Chemistry & Engineering .

Meenesh Singh, assistant professor of chemical engineering in the UIC College of Engineering and corresponding author on the paper, said:

“So far, all designs for artificial leaves that have been tested in the lab use carbon dioxide from pressurized tanks. In order to implement successfully in the real world, these devices need to be able to draw carbon dioxide from much more dilute sources, such as air and flue gas, which is the gas given off by coal-burning power plants.”

The only way that these artificial leaves will be able to collect and concentrate carbon dioxide (a potent greenhouse gas) from the air around us to drive their artificial photosynthetic reactions is if they are unhooked from the pressurized carbon dioxide supply.

Image: Meenesh Singh
Here’s how Singh and his colleague Aditya Prajapati, a graduate student in his lab, propose to solve this problem:
  • The traditional artificial leaf is placed inside a water-filled capsule constructed out of a semi-permeable membrane.
  • When the sunlight warms the water, it evaporates through the membrane – when that happens it gets the capsule to suck in carbon dioxide (co2).
  • The CO2 that’s been sucked in then gets converted into carbon monoxide (CO) and oxygen by the artificial leaf inside the capsule.
  • The carbon monoxide (CO) could be siphoned from the device and used to create synthetic fuels ranging from gasoline to methanol;
  • And the oxygen could be released back into the environment or collected.
In other words, all they have to do is envelope the artificial leaf technology (that has already been developed and works but only in the lab) within this specialized membrane and the whole unit will be able to function outside, like a natural leaf. Furthermore, according to their research, they believe that an artificial leaf built around their design would be 10 times more efficient at converting CO2 to fuel than natural leaves.

Their calculations reveal that 360 of their artificial leaves, each 1.7 meters long and 0.2 meters wide, would generate about half a ton of CO daily, which can be used as a basis for synthetic fuels. If those leaves were to be spread out over 500 square meters, then they could reduce the CO2 levels in the air within 100 meters of the space by 10 percent in just one day.

Singh concludes:

Our conceptual design uses readily available materials and technology, that when combined can produce an artificial leaf that is ready to be deployed outside the lab where it can play a significant role in reducing greenhouse gases in the atmosphere.

by Andrea D. Steffen
February 22, 2019

domingo, 27 de enero de 2019

Chemical Computing, the Future of Artificial Intelligence

In 1951, the Russian chemist Boris Belousov sent to a scientific journal a study in which he described an astonishing discovery: while trying to simulate a metabolic process in the laboratory, he had discovered a chemical reaction that occurred and then reversed itself on its own, alternating between a yellow colour and a colourless state. Belousov couldn’t find any journal willing to publish his results, since they appeared to violate a fundamental law of nature.

However, his work—which only came to light in 1959 through a brief presentation at a symposium—has become, half a century later, the foundation stone of a new discipline: chemical computing. This technological path is an alternative to quantum computing and conventional computing, capable of processing in parallel based on the same operating principles as our brain, promising futuristic applications, such as integrating in our body in the form of intelligent biosensors.

Portrait of Boris Belousov. Source: Wikimedia
Computing is based on the use of logic gates, which process a data input—usually in binary code—to produce a result or output. In the chips of our current computers, this function is carried out thanks to semiconductors, materials with a binary response capacity operating through the movement of electrons. However, this is not the only possible system; quantum computing, currently in the experimental phase, uses properties of subatomic particles that can also take alternative values, with greater versatility than semiconductors.

Until the discovery of Belousov, no one would have suspected that chemical reactions could act as logic gates. According to the second law of thermodynamics, these processes are linear, spontaneously moving towards equilibrium through an increase in entropy, a measure of the energy of chaos; what is done cannot be undone, at least on its own. For this reason, Belousov’s work was rejected and ignored, until a decade later it was recovered, extended and made known by the biophysicist Anatol Zhabotinsky.

THE FIRST CHEMICAL OSCILLATOR

The Belousov-Zhabotinsky reaction was the first chemical oscillator, a non-linear reaction that moves alternately in one direction and then the opposite as the process itself modifies the concentrations of the ions present, and which only stops when the reagents are consumed. In a Petri dish, these reactions produce waves of colours that diffuse from different points and act as inputs; the interaction between these input data can produce as an output a new wave—a 1, in binary code.

But this ability of chemical systems to compute by acting as logic gates is not something invented by humans, but was discovered, since it exists in nature. “We are already using chemical computers, because our brains and bodies employ communication via the diffusion of mediators, neuromodulators, hormones, etc.,” says computer scientist Andrew Adamatzky, director of the International Center of Unconventional Computing at the University of the West of England in Bristol. “We are chemical computers,” he summarises.

The Belousov-Zhabotinsky reaction is a non-linear reaction that moves alternately in one direction and then the opposite. Credit: Jkrieger
For decades it was believed that the brain’s computational capacity lay in the neuron as a minimal unit, and that its subcellular parts were limited to acting as simple transmitters of the decisions made by the cell in terms of the inputs received. Today it is known that this is not the case, and that discrete parts of the neuron, such as
  • the dendrites (the branches that receive the signals), 
  • the axon (which sends the impulse to other neurons), and 
  • the synapse (the space that communicates between them) 
are independently modulable, and therefore capable of computing by themselves. As this modulation is exerted through chemical agents, the brain is not an electrical computer, but an electrochemical one.

THE BRAIN, A PARALLEL COMPUTER

The great versatility of each neuron confers on the brain a valuable quality. “The brain and chemical computers are parallel computers,” explains biophysicist Vladimir Vanag, from the Centre for Nonlinear Chemistry at the Immanuel Kant Baltic Federal University (Russia). Parallel computing is not within the reach of conventional microprocessors (though it is for quantum ones). In practice, this advantage that chemical computing possesses overcomes one of its drawbacks—its slower speed.

(a) The array of the BZ microdroplets in a 1D capillary. (b) Spacetime plot for the dynamics of the BZ MDs at GNF with coefficient g e = 0.11. The total size of the space-time plot is equal to 1875 mm  424 s. Short horizontal bars depict spikes for each of the 15 BZ MDs. The averaged diameter d of a single MD equals 125 mm. The red arrow depicts the averaged period of oscillations, T 0 = 159 s. The slope of the blue line characterizes the ''velocity'' spike propagation, 1.68 mm s À1. Some droplets in snapshot (a) look lighter since they are in the oxidized state of the catalyst, the others look darker since they correspond to the reduced state of the catalyst. White dashes in droplets with index numbers (from 1 to 15) display the image reading area to record the ox-red state of the droplets. Compared with the great speed of electronic chips, chemical computing is limited by the speed of the diffusion of reactions in the medium. Researchers like Adamaztky are working on breaking this barrier: “Systems can be scaled down to the nano-scale and then everything will be fast,” he says. However, he notes that certain applications will not require higher speeds: “When reaction-diffusion computers are embedded in the human body, their speed of processing information will perfectly match natural processes.”

But in any case, Vanag explains with an example how parallel computing compensates for any speed limit: if a micro-oscillator—equivalent to a processor—occupies a cubic volume of 100 microns on each side, a single cubic centimetre could contain a million of them, all working in parallel. Thus, “we can increase the number of micro-oscillators by many orders of magnitude and overcome the speed of conventional computers,” he says. Say goodbye to Moore’s law; with chemical computing, a small increase in volume is enough to multiply the processing capacity. This is the secret of the human brain, slower than any computer, but more powerful than all of them.

The brain is slower than any computer, but much more powerful. Credit: Pixbay
A NEW ARTIFICIAL-INTELLIGENCE
In addition, chemical computing brings other crucial advantages. “It should work without electricity,” says Vanag. “No viruses, autonomous regime of working, and extremely high efficiency.” And all this while using just a few cheap chemical reagents. Thanks to these qualities, chemical computing is emerging as a promising alternative to simulate the human brain. By building bottom-up systems, starting with small oscillator networks and adding more and more layers of complexity, scientists are learning how cognitive functions such as image recognition or decision making appear.

Of course, a consequence of this chemical recreation of the brain would be the possibility of obtaining new artificial-intelligence systems, but radically different from what we usually envision: imagine robots made of gel, without a defined shape, capable of dividing themselves into smaller ones so that each one of them works independently. Perhaps they’ll even be embedded in our own bodies, analysing our biological parameters, curing our diseases. “But this is a fantasy,” concludes Vanag. “At the moment.


Javier Yanes




ORIGINAL: OpenMind

sábado, 26 de enero de 2019

David Attenborough: 'The Garden of Eden is no more'. Read his Davos speech in full

Hilde Schwab and Sir David Attenborough at the 25th Annual Crystal Awards.
Image: World Economic Forum / Manuel Lopez
Thank you, Professor Klaus Schwab, Hilde Schwab and the World Economic Forum for this generous award and inviting me to Davos.

I am quite literally from another age.

I was born during the Holocene- the name given to the 12,000-year period of climatic stability that allowed humans to settle, farm and create civilisations.

Those conditions fostered our unique minds, giving rise to international trade in ideas as well as goods making us the globally-connected species we are today.

Much of what will be discussed here is the consequence of that stability.

Global businesses, international co-operation and the striving for higher ideals these are all possible because for millennia, on a global scale, nature has largely been predictable and stable.

Now in the space of one human lifetime - indeed in the space of my lifetime all that has changed.
The Holocene has ended. The Garden of Eden is no more.
We have changed the world so much that scientists say we are now in a new geological age - The Anthropocene - The Age of Humans.

When you think about it, there is perhaps no more unsettling thought. The only conditions modern humans have ever known are changing and changing fast.

It is tempting and understandable to ignore the evidence and carry on as usual or to be filled with doom and gloom.

But there is also a vast potential for what we might do.

We need to move beyond guilt or blame and get on with the practical tasks at hand.

We did not get to this point deliberately – and it has happened astonishingly quickly.

When I made my first television programmes most of audiences had never even seen a pangolin - indeed few pangolin had ever seen a TV camera!

When in 1979 I made a series tracing the history of life on earth, I was aware of environmental problems but I didn’t imagine we were fundamentally changing nature.

In 1999, whilst making the Blue Planet series about marine life, we filmed coral-bleaching, but I still didn’t appreciate the magnitude of the damage that had already started.

Now however we have evidence, knowledge and the ability to share it on a scale unimaginable even just a few years ago.

Movements and ideas can spread at astonishing speed.

The audience for that first series, 60 years ago, was restricted to a few million viewers in southern England.

My next series - Our Planet- which is about to be launched, will go instantly to hundreds of millions of people in almost every country on Earth via Netflix.

And the evidence supporting the series will be free to view by everyone with an internet connection via WWF.

If people can truly understand what is at stake, I believe they will give permission to business and governments to get on with the practical solutions.

And as a species we are expert problem-solvers. But we haven’t yet applied ourselves to this problem with the focus it requires.

We can create a world with clean air and water, unlimited energy, and fish stocks that will sustain us well into the future.

But to do that we need a plan.

Over the next 2 years there will be United Nations decisions on Climate Change, Sustainable Development and a New Deal for Nature. Together these will form our species’ plan for a route through the Anthropocene.

What we do in the next few years will profoundly affect the next few thousand years.

I look forward very much to the discussions and insights this week

Thank you again for this great honour.

ORIGINAL: WEForum