Lifeboat Foundation: Safeguarding Humanity
Toggle light / dark theme

Blog

Category: chemistry

When it comes to turning a raw block of metal into a useful part, most processes are pretty dramatic. Sharp and tough tools are slammed into raw stock to remove tiny bits at a time, releasing the part trapped within. It doesn’t always have to be quite so violent though, as these experiments in electrochemical machining suggest.

Electrochemical machining, or ECM, is not to be confused with electrical discharge machining, or EDM. While similar, ECM is a much tamer process. Where EDM relies on a powerful electric arc between the tool and the work to erode material in a dielectric fluid, ECM is much more like electrolysis in reverse. In ECM, a workpiece and custom tool are placed in an electrolyte bath and wired to a power source; the workpiece is the anode while the tool is the cathode, and the flow of charged electrolyte through the tool ionizes the workpiece, slowly eroding it.

The trick — and expense — of ECM is generally in making the tooling, which can be extremely complicated. For his experiments, [Amos] took the shortcut of 3D-printing his tool — he chose [Suzanne] the Blender monkey — and then copper plating it, to make it conductive. Attached to the remains of a RepRap for Z-axis control and kitted out with tanks and pumps to keep the electrolyte flowing, the rig worked surprisingly well, leaving a recognizably simian faceprint on a block of steel.

Read more | >

“The changing nature of sea ice, with earlier and erratic periods of thaw, could be altering the processing and release of pollutants alongside key nutrients, which in turn affects biota at the base of the marine food web,” says environmental chemist Crispin Halsall, from Lancaster University in the UK.

Polyfluoroalkyl and perfluoroalkyl substances (PFAS) are known as ‘forever chemicals’ because they don’t naturally break down in the environment. Now a new study reveals the increasing pace of Arctic ice melt is leaking more of these chemicals into the environment.

PFAS don’t originate in the Arctic, but they do settle there – they’re used in all kinds of human-made products and processes, from pizza boxes to foam used to fight fires. Once released into the atmosphere, they’re often trapped in Arctic ice floes.

This is nothing new. But in a worrying new study by chemists from Lancaster University in the UK, it appears the concentrations of PFAS in bulk sea ice are closely related to the salinity of the water. So the more briny the sea, the more concentrated these forever chemicals get.

Read more | >

Humanity has a plastic problem, but who said the problem couldn’t also be tasty? Scientists are trying to come up with creative solutions to address the ever-growing issue every day, with some even converting plastic bottles into vanillin using bacteria. Most recently, two scientists have echoed this sentiment and won the $1.18 million (1 million euro) 2021 Future Insight Prize in the process by creating a food ‘generator’ concept that turns plastics into protein.

The names behind the project, which was initially funded by a Defense Advanced Research Projects Agency (DARPA) cooperative agreement award for $7.2 million over four years, are Ting Lu, a professor of bioengineering at the University of Illinois Urbana-Champaign, and Stephen Techtmann, associate professor of biological sciences at Michigan Technological University.

Their goal was to improve a process for converting plastic trash into protein powder and lubricants using a combination of chemicals and high heat (pyrolysis). The two scientists call their project a food ‘generator.’

Read more | >

Cigarette butts are a common type of litter for marine environments but AI-powered robot litter pickers could be the solution.

It seems many people leave behind more than just sandcastles when they go home after a trip to the beach. Beach litter is a recurring issue, and it is damaging our coastal environments and wildlife.

And there is one small item that is causing a big problem: cigarette butts. They may only be a few centimetres long, but they are full of microplastics and toxic chemicals that harm the marine environment. They don’t easily decompose, and when they come into contact with the water, harmful substances can leach out.

Unfortunately, they are also the most common type of litter, with an estimated 4.5 trillion discarded annually.

Read more | >

Hemispherical array of ultrasound transducers lifts objects off reflective surfaces.

Researchers from Tokyo Metropolitan University have developed a new technology which allows non-contact manipulation of small objects using sound waves. They used a hemispherical array of ultrasound transducers to generate a 3D acoustic fields which stably trapped and lifted a small polystyrene ball from a reflective surface. Although their technique employs a method similar to laser trapping in biology, adaptable to a wider range of particle sizes and materials.

The ability to move objects without touching them might sound like magic, but in the world of biology and chemistry, technology known as optical trapping has been helping scientists use light to move microscopic objects around for many years. In fact, half of the 2018 Nobel Prize for Physics, awarded to Arthur Ashkin (1922−2020) was in recognition of the remarkable achievements of this technology. But the use of laser light is not without its failings, particularly the limits placed on the properties of the objects which can be moved.

Read more | >

The photovoltaic effect of ferroelectric crystals can be increased by a factor of 1000 if three different materials are arranged periodically in a lattice. This has been revealed in a study by researchers at Martin Luther University Halle-Wittenberg (MLU). They achieved this by creating crystalline layers of barium titanate, strontium titanate and calcium titanate which they alternately placed on top of one another. Their findings, which could significantly increase the efficiency of solar cells, were published in the journal Science Advances.

Most solar cells are currently silicon based; however, their efficiency is limited. This has prompted researchers to examine new materials, such as ferroelectrics like barium , a mixed oxide made of barium and titanium. “Ferroelectric means that the material has spatially separated positive and negative charges,” explains physicist Dr Akash Bhatnagar from MLU’s Centre for Innovation Competence SiLi-nano. “The charge separation leads to an asymmetric structure that enables electricity to be generated from light.” Unlike silicon, ferroelectric crystals do not require a so-called pn junction to create the photovoltaic effect, in other words, no positively and negatively doped layers. This makes it much easier to produce the solar panels.

However, pure barium titanate does not absorb much sunlight and consequently generates a comparatively low photocurrent. The latest research has shown that combining extremely thin layers of different materials significantly increases the solar energy yield. “The important thing here is that a ferroelectric material is alternated with a paraelectric material. Although the latter does not have separated charges, it can become ferroelectric under certain conditions, for example at low temperatures or when its is slightly modified,” explains Bhatnagar.

Read more | >

Boston startup Form Energy has secured $200 million Series D funding for the development of what is being called a breakthrough in energy storage. #solarenergy #solarpv #solar

Solar and wind power have variability in their productive hours, as multi-day weather events can impact output. Therefore, multi-day storage that is cost effective is important in grid reliability.

Boston startup Form Energy developed technology to address this need, revealing recently the chemistry behind their iron-air batteries. The company said its iron-air batteries can deliver renewables-sourced electricity for 100 hours at system costs competitive with conventional power plants. At full-scale production, Form Energy said the modules would deliver electricity at tenth the cost of lithium-ion batteries.

The iron-air battery is composed of cells filled with thousands of iron pellets that are exposed to air and create rust. The oxygen is then removed, reverting the rust to iron. Controlling this process allows the battery to be charged and discharged.

Read more | >

The University of Surrey has built an artificial intelligence (AI) model that identifies chemical compounds that promote healthy aging — paving the way towards pharmaceutical innovations that extend a person’s lifespan.

In a paper published by Nature Communication’s Scientific Reports, a team of chemists from Surrey built a machine learning model based on the information from the DrugAge database to predict whether a compound can extend the life of Caenorhabditis elegans — a translucent worm that shares a similar metabolism to humans. The worm’s shorter lifespan gave the researchers the opportunity to see the impact of the chemical compounds.

The AI singled out three compounds that have an 80 percent chance of increasing the lifespan of elegans:

Read more | >

A new tool that enables thousands of tiny experiments to run simultaneously on a single polymer chip will let scientists study enzymes faster and more comprehensively than ever before.

For much of human history, animals and plants were perceived to follow a different set of rules than rest of the universe. In the 18th and 19th centuries, this culminated in a belief that living organisms were infused by a non-physical energy or “life force” that allowed them to perform remarkable transformations that couldn’t be explained by conventional chemistry or physics alone.

Scientists now understand that these transformations are powered by enzymes – protein molecules comprised of chains of amino acids that act to speed up, or catalyze, the conversion of one kind of molecule (substrates) into another (products). In so doing, they enable reactions such as digestion and fermentation – and all of the chemical events that happen in every one of our cells – that, left alone, would happen extraordinarily slowly.

Read more | >