Category Archives: Science

Environment, Science, Technology, United States

Ammonia is being developed as a low-carbon fuel

ENVIRONMENT

Intro: A start-up in America is developing world’s first ammonia-powered ships

THE Brooklyn Navy Yard’s sprawling industrial complex once employed 70,000 workers to build US battleships and aircraft carriers during the second world war. Almost 80 years later, it has become home to a New York city firm with a very different maritime mission – harnessing ammonia as a low-carbon fuel for the global shipping industry.

The start-up Amogy has already shown how ammonia-powered technology can work in a flying drone, a John Deere tractor and most recently a truck. Now, it is working on an ammonia-powered ship.

Most ships currently run on fossil fuels that emit greenhouse gases, accounting for 3 per cent of the world’s carbon emissions. One alternative involves converting vehicles to hydrogen power that would only emit water. But hydrogen gas needs to be compressed and liquified at -253°C for storage and transportation.

Ammonia could serve as an alternative hydrogen-bearing fuel that is more easily stored and transported in a stable liquid form at room temperature.

Hydrogen can be extracted by heating ammonia to high temperatures, which is a process that comes with its own energy cost. This is where Amogy’s technology comes in. To make ammonia power more viable, the company has developed what it describes as a more efficient and miniaturised “ammonia cracking” method that can chemically extract hydrogen from ammonia at a lower temperature. It uses a proprietary catalyst to speed up the process inside a chemical reactor that feeds into a hydrogen fuel cell.

A leading chemist at Saint Mary’s College of California says that what Amogy was able to bring to the table is that by having better catalytic technologies (all proprietary) they were able to miniaturise their ammonia cracking units and put them on board vehicles.

It was in July 2021 when Amogy first showed that its system could supply 5 kilowatts of power to a drone. By comparison, a standard ammonia cracking system for extracting that amount of hydrogen power is usually the size of a large shipping container. It also paved the way for a 100-kilowatt tractor demonstration in May 2022. That was followed by a 300-kilowatt truck demonstration in January 2023. The firm is now working towards demonstrating a 1-megawatt system in a tugboat.

Many countries already have pipelines and port facilities for handling ammonia that is produced industrially as fertiliser for agriculture. The US alone has more than 5000 kilometres of ammonia pipelines compared with 2500 kilometres of pipeline for transporting hydrogen – though it will need more to support ammonia-powered vehicles.

Another challenge is that ammonia still “has a carbon footprint associated with the production” because the standard industrial process uses natural gas. Low-carbon ammonia production would require use of carbon capture.

Cleaner alternative methods could ideally use electricity from renewable power sources to split water into hydrogen for conversion to ammonia.

. Science Book: Chemistry

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Research, Science

Scientists reveal that the proton’s size is moveable

PARTICLE PHYSICS

Intro: The radius of the proton, a subatomic particle, seems to vary depending on how you look at it

THE proton, one of the building blocks for all matter, is proving to be an awkward customer to size up. If you look at its charge, it will have one radius, but if you look at its mass, you will see a different, smaller radius.

A new picture of the proton is emerging. In the 1960s, experiments that fired electrons at protons revealed that the latter contained point-like, electrically charged particles that we now call quarks. A proton has two up quarks and a down one. Quarks were later found to be bound together by particles called gluons.

We now know more about quarks and how far their electric field extends in space, which is sometimes called the radius of the proton. But we know less about gluons, which contain most of the mass of the proton in the form of energy, because they are chargeless, and so much harder to investigate. Seeing how they are distributed can tell us about how the proton’s mass is arranged and its structure.

Scientists at the Argonne National Laboratory in Illinois have probed the proton’s gluons with particles called J/psi mesons. This is possible because even though gluons don’t have electric charge, they have a property called colour charge, which comes from the strong nuclear force, one of the universe’s four fundamental forces. J/psi mesons are made up of a charm quark and its antiquark, which also have colour charge and so are capable of interacting with gluons.

The researchers fired a beam of photons at liquid hydrogen, which is comprised mainly of just protons, and the photons interacted with the protons. These collisions produced short-lived J/psi mesons. By measuring how many of these were produced, the research team could calculate the proton’s mass distribution using quantum mechanical models that describe gluon-quark interactions.

Their results suggest that the gluons’ mass is confined to a dense core in the proton’s centre, while the charge from the quarks extends to a second, larger radius.

They also compared their results with predictions from another model of the proton, which agreed in some places and diverged at others, suggesting that the new figures need validating with more precise experiments or one that probe proton structure in a different way.

If it is confirmed, it will be a very interesting finding because it tells us something quite deep about how the proton’s constituents behave from a spatial point of view.

A different internal structure could have implications for calculating other proton properties, such as spin, angular momentum and energy distribution, which many sensitive experiments rely on. But some of the new proton findings rest on models used to calculate them, which haven’t proved entirely reliable in the past.

The results follow another revelation about the proton’s internal structure. Last year, a research team found that the proton can contain a much heavier charm quark, in addition to the three regular quarks, but asked: ‘Does the mass radius become larger or smaller?’

. Further understanding on quarks can be found:

Science Book: Physics

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Health, Science, Society, United Nations, World Health Organisation

Global cases of cholera are on the rise

CHOLERA

CASES of cholera are increasing, with 22 countries around the world experiencing an outbreak. After many years of decline, incidences rose in 2022 due to vaccine shortages, climate change and escalating conflict. It is a trend that is expected to continue.

. Science Book

Some 26,000 cholera cases were reported in Africa during the first 29 days of January 2023. This is already 30 per cent of the continent’s total in 2022. At the end of February, the World Health Organisation (WHO) said that more than 1 billion people across 43 countries are at risk.

Overall, Malawi appears to be the worst-hit country, with the highest number of deaths. It reported just under 37,000 cholera cases and 1,210 fatalities from 3 March 2022 to 9 February 2023.

This was triggered by a cyclone that hit in March 2022. This led to wastewater contaminating drinking water supplies.

Cholera is spread by the ingestion of food or water that is contaminated with the bacterium Vibrio cholerae. When it enters the body, some types of V. cholerae release a toxin that interacts with the cells lining the surface of the intestine, leading to diarrhoea.

In some cases, this can result in severe dehydration and death. In Malawi, 3.3 per cent of people with cholera die of the infection. With treatment, this is typically around 1 per cent.

In 2022, Malawi vaccinated millions of people in districts that were facing cholera outbreaks, but the cyclone has allowed the disease to spread to all of its districts, putting unvaccinated people at risk.

Extreme weather, driven by climate change, means many more countries are at risk of wastewater contamination. Cyclone Freddy, which hit Mozambique on 24 February, is expected to exacerbate the country’s cholera outbreak.

Climate change-driven droughts in countries such as Kenya and Ethiopia have also forced people to rely on water sources that may be contaminated with V. cholerae, according to UNICEF. Many people in these regions are malnourished, which affects their immune health, leaving them more vulnerable to severe cholera complications.

Displacement, whether due to conflict in countries like the Democratic Republic of the Congo or disasters such as the earthquake that hit part of Syria on 6 February, can also play a role in cholera outbreaks if people are forced to move to less sanitary areas, or if already infected people take the bacteria with them.

The destruction of health facilities and infrastructures [in Syria] that bring water to people could lead to more cases. According to the United Nations, the country reported more than 37,700 suspected cases in the cities of Idlib and Aleppo from 25 August 2022 to 7 January 2023 – 18 per cent of which were in people in displaced camps.

The unprecedented scale of the cholera outbreaks in 2022 – with 30 countries reporting cases, compared with an average of fewer than 20 in the previous five years – has also depleted global vaccine supplies. Only 37 million doses are available.

The International Coordinating Group on Vaccine Provision, which manages the WHO’s global vaccine stockpile, therefore recommends that at-risk people be vaccinated with a single dose of a cholera vaccine rather than the typical two doses. The one-dose regimen gives only about one year of protection, compared with three years with two doses. If the outbreaks continue as they are, this year of protection might not be enough time to get them under control.

Cholera has always been an issue, which prompted the UN to publish a road map in 2017 to cut 90 per cent of cholera deaths globally by 2030.

Several countries have made progress. The fact that Malawi has detected cholera outbreaks so quickly points to the work that officials have done to increase health surveillance.

But with just seven years to go until 2030, many aren’t convinced that the UN’s target will be reached. They say there hasn’t been enough investment in water infrastructure around the world to reach those goals.

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