Cooperation for survival

by Hansraj Agrawal | Jan 21, 2024 | Science

Put an ant into a glass of water, it dies in minutes, despite its desperate attempts to swim and stay afloat.

But it turns out that thousands of ants can stay afloat in water together; they even use this technique to travel in water.

Ants form a floating raft by interlocking one’s jaws to another’s legs, when their nests flood—a splendid example of cooperation to survive. Some scientists say the ants do this to protect the queen—the queen is needed to produce offspring for the entire colony.

Scientists say that the ability of ants to raft afloat as a group has to do with the ‘cheerios effect’, which says that when a liquid touches a solid, the liquid curves upwards at the edges of the solid, creating a ‘cup’. The air in the cup allows buoyancy for the solid object to float. You can experiment with this by gently placing a coin on a bowl of water, and watch it float.

The ability of fire ants to work together to form large structures has fascinated scientists—not just biologists but also engineers. When these structures are formed, it is seen that no single ant directs all the action. Roboticists are wondering if they can learn something from this and apply the learnings in modular robotics—taking biomimicry to the next level.

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Making green hydrogen from coke cans

by Hansraj Agrawal | Jan 21, 2024 | Science

Producing hydrogen without greenhouse gas emissions is hard and expensive, right? Wrong!

All you need to do is to take several coke cans, shred them into metal scrap and put them into a bucket of water. Out comes hydrogen.

But the problem is, the amount of gas that gets produced by this method is so small that it’s hardly worth the effort. This is because the oxygen in the water quickly reacts with the surface aluminium to form a film of oxide, which prevents further reaction. The answer is to find a chemical (a catalyst) that will scrub off the oxide layer. Some researchers have used gallium for that purpose. Others have shown that if you use a fine dust of silicon-doped aluminium, the hydrogen yield is pretty high.

However, aluminium is costly. Indeed, you can use aluminium scrap, but scrap is never pure metal; it comes alloyed with other materials, which hampers hydrogen production.

‘Production of hydrogen using metal scrap’ is a subject matter of intense research today.

A group of scientists headed by Professors RB Harikrishna, Hemagni Deka, T Sundararajan and G Ranga Rao, of the Department of Chemical Engineering, IIT Madras, have demonstrated that discarded metal wastes can be used as feed-materials for thermochemical production of green hydrogen. The gas is produced by splitting water using industrial waste-metal scrap at high temperatures. This process requires significant energy input in the initial stage to attain the desirable temperature. Subsequently, the energy input can be reduced due to the exothermic nature of the process, the researchers note in a recent publication in The International Journal of Hydrogen Energy. They studied the reaction between metal scrap and steam for hydrogen production. Their method produced 500 mL of green H2 per gram of scrap material at 1150°C, with a conversion efficiency of about 94 per cent. “This is a potential method to utilise scrap metals for large scale production of green hydrogen without carbon emissions,” they say. Through this process, a ton of metal waste can produce approximately 5,00,000 litres of hydrogen. The byproduct produced is primarily magnetite, which is a potential additive for magneto-rheological fluids. This is an environmentally friendly process and can be developed as a cost-effective method for green hydrogen production. There are many other types of scrap metal materials which can also be employed to generate hydrogen by this process.

Monolithic gain

Meanwhile, US-based company in Nebraska called Monolith has claimed to have developed a technology for producing cheap green hydrogen using methane pyrolysis. It still uses natural gas, but says the emissions are just 0.45 kg of CO₂, per kg of hydrogen produced compared with 11.3 kg of the conventional, ‘steam methane reforming’ process. If the feedstock is from biogenic or recycled sources, CO₂ emissions will be negative, says Monolith.

The company is backed by investors such as Decarbonization Partners, Mitsubishi Heavy Industries, Warburg Pincus and TPR Rise Climate.

The process is simple—use electricity to super-heat methane. The process needs one-seventh of the electricity that an electrolyser would (about 55 kWhr per kg of Hydrogen). The heat breaks the bonds between the hydrogen and carbon atoms on the CO₂ molecule. Hydrogen and carbon atoms emerge out of the contrivance separately, so you end up with two useful products—hydrogen and carbon black.

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Era of high-capacity small satellites

by Hansraj Agrawal | Jan 21, 2024 | Science

Agnikul Cosmos, the Indian start-up, which is building small rockets to launch small satellites, is aiming for 30 launches a year—for starters. Its mentor, Dr Ashok Jhunjhunwala, President, IIT Madras Research Park, where Agnikul is incubated, recently said the company would build 300 rockets a year.

“There is a lot of scope,” says Srinath Ravichandran, Co-Founder and CEO of the space start-up, which is close to conducting its first sub-orbital test. “About 100 tonnes of small satellites go up to orbit per year,” he told Quantum.

Agnikul’s plans flag an increasingly obvious trend: we are witnessing the dawn of the era of small satellites.

Another fact illustrates the trend. In September 2023, when ISRO offered to transfer its small satellite launch vehicle technology to private companies, as many as 23 companies applied.

Small satellites have been around for some time now. Back in 2009, students at the Anna University in Chennai built Anusat, to study gravity and magnetic fields, which was put in orbit by an ISRO rocket. But now, the world is witnessing a big shift with the emergence of high-capacity small satellites. For example, the satellites of Elon Musk’s space internet company, Starlink (which, incidentally, is expected to get approval for Indian operations this week), are equipped with Krypton-powered ion thrusters, autonomous collision avoidance systems and star trackers. They weigh just 260 kg (though the upcoming Starlink satellites are three times as heavy). Sunil Bharti Mittal’s OneWeb has over 600 satellites, weighing about 150 kg, also equipped with items such as automatic collision avoidance systems.

While Starlink and OneWeb’s satellites are meant to provide space-served internet, other small satellites aim to do much more.

EU’s bid for space

By 2027, the European Union aims to have a constellation of 200 satellites to guarantee its sovereignty in space under its IRIS programme (Infrastructure for Resilience, Interconnectivity and Security by Satellite). The project aims at making sure of critical networking infrastructures and facilitate crisis management by governments, to supplement its terrestrial networking infrastructure. “The possibility of cheaper mass production would enable construction of large satellite constellations for entirely new commercial services and scientific applications,” says Prof Frank Schäfer, head of the Space business unit at the Fraunhofer Institute for High-Speed Dynamics EMI, based at Freiburg, Germany.

Prof Schäfer’s institute is also building military grade satellites for the German Federal Armed Forces (Bundeswehr). A military satellite called ERNST, which is about half the size of a beer crate, is being built by the institute to detect missile launches from anywhere in the world. Placed in the low-earth orbit, it features an infrared camera that can sense the heat emitted by a missile engine. But this camera can do much more—it can, for example, detect forest fires, greenhouse gas emissions and measure sea temperatures.

Fraunhofer institute sees ERNST as a platform that can generate “experiential data” for designing small satellites with high-capacity equipment. “These findings are being included in the plans for more such small satellite constellations in the future,” Schäfer told the institute’s in-house magazine.

The future high-capacity small satellites will include technologies such as “beam hopping” by which one antenna can cover multiple areas. These satellites are equipped with ‘modular phased array antennas’ and are flexible because their individual beams can be electronically controlled.

While the early small satellites were mostly one-trick ponies, the modern ones are far more potent, capable of multi-tasking. By the looks of it, their tribe—like Abou Ben Adham’s—will only increase. Launch service providers like Agnikul Cosmos are understandably excited about the prospect.

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Regulating AI: How to bell the cat?

by Hansraj Agrawal | Jan 21, 2024 | Science

With the forest-fire-like spread of AI—in our lives and possibly our jobs—there is a rising fear and scepticism about how AI will improve our lives. The fear is from two directions: fear of missing out (FOMO), and fear of new technology and loss of livelihood.

As more and more applications of AI are discovered, there’s a growing discomfort—even among the proponents of AI—around the amount of control we unknowingly cede to AI and those who own it. As always, with rapidly-spreading new technology, there’s a race between control and utilising its potential.

The European Union was one of the first to act in this area by publishing its “White Paper on Artificial Intelligence: A European Approach to Excellence and Trust” on February 2, 2020, long before all the melee around generative and general-purpose AI began. The same is the case with EU’s groundbreaking AI Act, the first draft of which was proposed in April 2021. The Act was adopted on June 14, 2023 and is set to come into effect in late 2025.

Meanwhile, the US’ approach to regulating AI has been somewhat different from that of the EU. While there is no specific Act or law for around AI regulation, the Biden administration has set new standards for AI safety with an ‘Executive Order on the Safe, Secure and Trustworthy Development and Use of Artificial Intelligence’ on October 30, 2023. The order aims to exercise a soft authority on AI and leverages the powers of federal agencies, particularly those around consumer protection. On October 4, 2022, the US President Joe Biden unveiled a ‘AI Bill of Rights’, which outlined five protections that Americans should have in the AI age—safe and effective systems; algorithmic discrimination protection; data privacy; notice and explanation; and human alternatives, consideration and fallback.

The AI Act: A breakdown

Given the EU’s path-breaking legislation and enforcement around the digital economy, including the famous General Data Protection Regulation (GDPR), and that the rest of the world uses the EU legislation for a model, it’s interesting to see how the EU’s AI Act regulates AI.

The AI Act focuses on the kind of risks arising from AI applications and classifies them into unacceptable, high, limited and minimal.

Unacceptable risk in AI systems are those that are considered a threat to people and will be banned. They include: cognitive behavioural manipulation of people or specific vulnerable groups; social scoring; biometric identification and categorisation of people; and real-time and remote biometric identification systems— such as facial recognition. There are certain exceptions available for the maintenance of law and order, with specific controls.

The AI systems that negatively affect safety or fundamental rights are considered high risk and will be divided into two categories: AI systems that are used in products falling under the EU’s product safety legislation (including toys, aviation, cars, medical devices and lifts); AI systems falling into specific areas that will have to be registered in an EU database (including management and operation of critical infrastructure, education and vocational training, employment, worker management and access to self-employment, access to and enjoyment of essential private services and public services and benefits, law enforcement, migration, asylum and border control management, assistance in legal interpretation and application of the law). All high-risk AI systems will be assessed before being put on the market.

Limited risk AI systems will have to comply with minimal transparency requirements that would allow users to make informed decisions. Users should be made aware when they are interacting with AI. This includes AI systems that generate or manipulate image, audio or video content, for example deepfakes.

The EU also has recommendations for general purpose and generative AI—disclose that the content was generated by AI; design the model to prevent it from generating illegal content; and publish summaries of copyrighted data used for training.

In addition, high-impact models would have to undergo thorough evaluations and serious incidents would have to be reported to the European Commission.

What about India?

On the home turf, India passed the Digital Personal Data Protection Act in 2023 which has its hands on data protection, privacy and consumer protection as an outcome of AI. We can also expect the proposed Digital India Bill, 2023, to have more specific rules and regulations around AI and its applications. India is also collaborating on worldwide AI policymaking by being part of the Global Partnership on Artificial Intelligence (GPAI).

So, how do we expect policies on AI to evolve? A recent EY report highlights six regulatory trends:

1. Core principles such as respect for human rights, sustainability, transparency and strong risk management.

2. Following a risk-based approach where regulations are tailored to the perceived risks of AI to values like privacy, non-discrimination, transparency and security.

3. Sector-agnostic regulation and sector-specific rules.

4. AI-related rulemaking within the context of other digital policy priorities such as cybersecurity, data privacy and intellectual property protection.

5. Private-sector collaboration with the core objective of promoting safe and ethical AI, as well as to consider the implications of higher-risk innovation associated with AI where closer oversight may be appropriate.

6. International collaboration, driven by a shared concern the risks to safety and security posed by powerful new AI systems

A large part of the EU’s AI Act spreads across all six of the trends, making it the most comprehensive even if highly critiqued approach to regulation. Recent announcements, events and government releases indicate that India has a similar path in front of it.

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New light weight anode material for Li-ion battery

by Hansraj Agrawal | Jan 7, 2024 | Science

The discovery of new, functional materials is all about manipulating the elements to form compounds as needed. This, in turn, often involves breaking the bonds.

Sonochemistry, or using high-frequency sound waves, way above human hearing range, is one of the techniques for breaking the bonds. When high-intensity sound waves slither through a watery medium, they create extremely tiny bubbles that form and collapse rapidly. This process produces extremely high temperatures and pressures.

Sonochemistry is not something new. It has been long known to scientists but seems to be making a come back for newer applications today.

Prof Kothandaraman Ramanujam of the Department of Chemistry, IIT Madras, has synthesised a new material called ‘hydride-stabilised boron nanosheets’ (H-BNS) through this technique. There are many applications of this material, but the notable three include its use as — anode material for Li-ion batteries, reducing agent for organic reactions and a medium for storing hydrogen.

Their experiments have been published in a paper in the journal ChemComm.

Making of H-BNS

Kothandaraman and his students, Swati and Dr Anand, fired sonic waves into the water that had boron, after which they allowed time for unreacted boron particles to settle down—which were removed by a centrifuge. Then the supernatant solution was centrifuged at much higher speeds and longer to collect the ‘hydride-stabilised boron nanosheets’.

What happens is, the sonic waves break the bonds between hydrogen and oxygen in water molecules simultaneously boron-boron bonds freeing boron atoms to form 2D materials. Some of the nascent hydrogen atoms pick up an extra electron from 2D boron sheets and become ‘hydrides’. These hydrides go and ‘sit’ on the boron slabs (or ‘borophites’, which are multiple layers of borophene sheets). “Sonication helps in breaking boron-boron bonds and production of hydrides,” explains Kothandaraman. The hydride settles down on the boron nanosheets, forming H-BNS.

The team measured the thickness of H-BNS using ‘atomic force microscopy’ and found it to be ~ 20 nm thick. This indicates the formation of borophites (a one-atom thick, 2-dimensional sheet of boron).

Now, if you ‘intercalate’ (or insert) lithium into H-BNS, you have yourself a potential anode material for a lithium-ion battery. Boron is lighter than carbon (graphite) and hence these batteries could have higher energy densities if optimised. And, boron is plentifully available in nature. “The potential use of H-BNS for lithium-ion battery applications was successfully demonstrated in half-cell mode,” says Kothandaraman.

Furthermore, the use of H-BNS as a reducing agent has also been studied and confirmed. Since H-BNS has hydride, it is a potential hydrogen storage material, useful for fuel cells.

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Bringing back the dead

by Hansraj Agrawal | Jan 7, 2024 | Science

In Roald Dahl’s William and Mary, the dead William’s brain, optic nerve and the eye are kept ‘alive’ in solution — the eye can ‘see’ and the brain can know what the eye is seeing. When he lived, William was a wife-abuser and now Mary took revenge by smoking a cigarette in the eye. The short story opens a scientific question: when is one really dead?

Until the 1960s, a person died when the heart stopped beating, but then came ‘Cardiopulmonary resuscitation’— CPR, which means that a still heart was not cessation of life. Now, scientists are taking it much further. Work is on to show that hours after ‘death’, brain functions can be revived. “Under appropriate conditions, certain molecular and cellular functions in the large mammalian brain may retain at least partial capacity for restoration after a prolonged post-mortem interval,” says a scientific paper on ‘Restoration of brain circulation’.

The brain stops functioning minutes after it stops receiving oxygen through blood pumped from the heart. But who is to say that if it starts receiving oxygen again after, say, a few hours, the cells will not come alive? In other words, it is possible to “treat” death. Yale University professor, Stephen Latham, who was part of a research that was able to revive brain functions of dead pigs, using a blood-infusing device that they call OrganEx, has told MIT Technology Review, that the line between life and death isn’t as clear as we once thought, and “death takes longer than we thought and at least some of the processes can be reversed.”

The brain surviving long periods of oxygen deprivation is a big breakthrough, which opens possibilities of reviving dead people with all organs intact — such as those who drowned.

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