Author Archives: raymond tang

Nuclear Power: A Solution to the Australian Energy Crisis or a Risky Gamble?

Australia is currently in the midst of an energy crisis. Electricity prices have risen significantly as coal-fired power plants around the country are shutting down, lowering electricity supply in a time where demand is skyrocketing.

As Australia is exploring new ways to generate clean and efficient electricity, one possible, yet controversial alternative have been proposed: nuclear power.

Nuclear power generates electricity by splitting radioactive isotopes, such as uranium-238, in a process called nuclear fission. The heat produced from this process is then used to heat water, which turns into steam and spins turbines to generates electricity.

Nuclear power plant. Source

Proponents of nuclear power argue that nuclear power is a clean and efficient energy source. Unlike fossil fuels, nuclear power generates little to no greenhouse gases. This makes nuclear energy a viable option for combating climate change and can help lower carbon emissions in Australia, allowing the country to meet its emission goals.

Another advantage of nuclear power is its reliability. Nuclear power plants are reliable because they can provide a consistent and reliable source of electricity as nuclear power plants require less maintenance and are designed to operate for long periods before refueling. This is in contrast to renewable energy sources such as wind or solar, which are less reliable as they are dependent on fuel availability (wind and sunlight) and require large-scale storage.

Despite the benefits of nuclear power, there are opponents who raise concerns about its safety. One reason behind this opposition is the potential for accidents. Nuclear meltdowns such as Chernobyl and Fukushima Daiichi have resulted in radioactive leaks and serious health risks for people living nearby. In fact, the areas surrounding these accidents sites have been left uninhabitable for the foreseeable future.

Damage to the Fukushima Nuclear Power Plant following the 2011 earthquake and tsunami. Source.

Another risk associated with nuclear power is the issue of nuclear waste. Nuclear power plants generate radioactive waste that can remain hazardous for thousands of years.

Radioactive waste generated from nuclear power plants poses a risk of environmental contamination, causing harm to people, animals, and the ecosystem. This waste needs to be carefully stored and disposed of to prevent contaminating the environment.

The debate over nuclear power is likely to continue for many years to come. While there are certainly benefits to nuclear power, it is also clear that there are associated risks. As Australia faces the current energy crisis, it should consider nuclear power as a viable option for generating electricity to overcome this crisis.

~ Raymond Tang

Missing Capsule of Cesium-137 Sparks Manhunt in Western Australia

Authorities in Western Australia have quite literally found a radioactive needle in a haystack.

Carrying case for radioactive capsules. Source.

On January 12th, a tiny capsule of radioactive cesium-137 from a radiation gauge fell off a transport truck that was on its way from a Rio Tinto mine site to a storage facility in Perth, Western Australia, along a 1400 km stretch of highway in the rural Australian outback.

Due to the radioactive nature of cesium-137, Australia’s Department of Fire and Emergency Services, as well as nuclear scientists quickly launched a desperate search for the tiny capsule, about 8 mm in length. As the search intensified, the public was warned to say at least 5 meters from the radioactive capsule.

Figure 1: The bar chart compares the size of cesium-137 to the size of commonly used Australian coins.

Cesium-137 is a radioactive isotope that is formed from the nuclear fission of uranium-235. Although it is tiny, cesium-137 is very dangerous to the health and wellbeing of anyone who come in contact with it. The radioactive isotope can emit both beta and gamma rays, which can penetrate skin, causing severe radiation burns, sickness, or even death.

Capsule of cesium-137. Source.

With a half-life of about 30.05 years before decaying to barium-137m, a stable and non-radioactive isotope. However, “the cesium inside the capsule will [still] be dangerous [until] the next century.” That is according to Edward Obbard, a nuclear materials engineer with the University of New South Wales.

Miraculously, on February 1st, the radioactive capsule of cesium-137 was found just off the side of the highway around 200 km from the mining site. Authorities quickly cordoned off a 20 meter perimeter and safely contained the capsule inside a lead container.

It is important for companies to be extremely careful when transporting radioactive substances. This incident highlights the need to scrutinize the transport of radioactive substances so that a similar incident will not happen again in the future.

–Raymond Tang

Enzymes – A Solution in the War Against Plastics

It should not be a surprise to people that it can take over 500 years for UV radiation – light from the sun to break down a piece of plastic. But what if there is a faster way to break down single-use plastics?

Researchers at the University of California, Berkeley invented a new way to decompose consumer plastics in a short amount of time, simply with heat, water, and nano-dispersed enzymes.

Plastic waste covering the shoreline. Source

UC Berkeley professor Dr. Ting Xu and her research group developed a nanoscale enzyme that can eat away at the polymers in plastics. These nanoscale polymer-eating enzymes can be embedded into plastics during manufacturing. The enzymes were wrapped around plastic resin beads. These beads are melted and can be manufactured into single use consumer plastics. To prevent the enzymes from activating when not required, a random heteropolymer (RHP) coating is applied to hold enzymes without restricting the flexibility of tensicity of the plastics.

Xu likened this process to organic composting. By adding water and heat, the RHP polymers is removed and starts eating away the polymers into smaller subunits.

The research conducted by Xu and her group found that the enzymes took about a week to degrade most of the plastics. Polylactic acid (PLA) and polycaprolactone (PCL) based plastics embedded with nanoscale polymer eating enzymes are able to break down the polymer chains into smaller molecules, such as lactic acid.

Plastic cups made from biodegradable plastics. Source

It is clear there is still more research needed in this field. Currently, Xu is developing other modified RHP-wrapped enzymes that can stop the degradation process at specific points in it’s degradation so that the polymers can be recycled into new plastics.

“[Humans] are taking things from the Earth at a faster rate than we return them,” said Xu. “Don’t go back to Earth to mine for these materials, but mine whatever you have, and then convert it to something else.”

As consumers, we can play an important role reducing our consumption on single use plastics and create a more sustainable environment for ourselves and future generations.

Raymond Tang

Enzymes – A Solution in the War Against Plastics

According to the United Nations Environment Programme, today, “about 400 million tonnes of plastic waste” is produced every year. The amount of plastic waste generated has risen significantly in a single decade compared to the last 40 years.

One of the biggest problem with plastic waste is that plastics can not breakdown in a short period of time. It can take up to 500 – 800 years for a piece of plastic to be broken down by UV radiation – light from the sun.

Plastic waste along the shoreline. Source

Researchers at the University of California, Berkeley have invented a new way to decompose polyester based plastics much quicker. Simply with heat, water, and nano-dispersed enzymes.

Dr. Ting Xu, a UC, Berkeley professor and her research group developed an enzyme that is able to eat away at the polymers in plastics. These nanoscale polymer-eating enzymes are embedded into plastics as they are being made. To prevent the enzymes from activating when not required, a random heteropolymer (RHP) coating is applied to hold the enzymes without restricting the flexibility of tensicity of the plastics.

Plastic cups made from biodegradable plastics. Source

The enzymes were wrapped around plastic resin beads. These beads were then melted and molded into usable consumer plastics. Xu likened this process to organic composting. By adding water and heat, the enzymes, the RHP polymer coating is removed and starts eating away the polymers into smaller subunits.

It is clear that there is still more research needed in this field. Currently, Xu is developing other modified RHP-wrapped enzymes that can stop the degradation process at specific points in it’s degradation so that the polymers can be recycled into new plastics.

Moving forward, Xu has high hopes for the polymer eating enzymes to change the way we look at recycling and that it will start a conversation about the way humans interact with the Earth.

According to Xu, “[humans] are taking things from the earth at a faster rate than we can return them. Don’t go back to Earth to mine for these materials but mine whatever you have, and then convert it to something else.”

~ Raymond Tang