Monthly Archives: May 2017

Digging Deeper

Article by Maram Razouki, student of INTO Manchester and runner up in our 2017 Science Journalism contest.

Can one doughnut kill you? Not quite, but something thing the size of a doughnut could very much do so. A landmine, not much bigger than a pastry, triggered by the slightest pressure could demolish a human body in a matter of seconds or if lucky, cause a permanent disability.

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There are two types of land mines: anti-vehicle and anti-personnel mines.  The anti-vehicle mines are large and the power of their explosion would obliterate an immense tank effortlessly, which shockingly is why they are not the problem. Because they are activated by very high pressure, such as that of a tank, and their bulky size they can easily be identified and extinguished by De-miners with ease.  On the other hand, the human-targeting low pressure activated anti-personnel mines are the needle in the stack of haystack; they have very little metal and are virtually impossible to detect accurately by existing metal detectors.

According to Dr. Liam Marsh, there are over 110000000 active land mines in the world which will require 1100 years to demine despite the fact that it takes minutes to implant thousands of them. To add insult to injury, for every 5000 mines removed one person from the demining team dies and two are injured. In addition, areas of land that contain mines are practically waste land as they are uninhibited due to their threat and are uncultivable which is a disaster considering the status of our world food bank in the past decades.

Although not ideal, the most popular tool used in demining is the metal detector. The  problem with metal detectors currently on the market are summed up as follows: firstly, current metal detectors are programmed to detect all metals including the abundant debris in the soil of war zones and high iron levels in soil (noise) ; this creates confusion and false alarms to the de-miners. Secondly, the majority of anti-personnel mines contain the minimum amount of metal possible and hence are hardly ever detected by a metal detector.

Dr. Marsh’s five-year minimum-metal landmine identification project was a successful attempt to increase the efficiency of the demining industry and the metal detectors used in particular. To overcome such obstacles, the project combines the properties of the existing metal detectors with those of the ground penetrating radar (GPR). The GPR calculates how far the object is underground by transmitting radio signals into the ground and as the reflected signals return it measures the time taken to and from the object calculating the distance accordingly. In addition, Dr.Marsh’s project creates profiles, similar to unique figure prints, to all objects based on their properties, for example, composition of iron by reducing the noise around a land mine.  It therefore acts as a sensor that would identify what the object is and how deep it is underground before wasting time and effort on professional digging. In practice, profiles of numerous objects would be created in the laboratory and installed on the project’s system; the project will then match the properties of the object detected to the matching profile on its system and using the radar technique calculate how deep the object is.

This project is important because it would identify mines with very little metal that current metal detectors cannot detect and this increase the safety of the demining process in addition to making the process more efficient. Hence, Dr. Marsh is optimistic and believes that the project facilitates the mine-clearing process and therefore is an important step towards a mine-free world.

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A HUNT ON EXPLODING CASSEROLE DISHES

Article by Greta Horvathova, student of Oswestry school and runner up in our 2017 Science Journalism contest.

How would you react, if someone told you that somewhere close to your home lies a landmine, an old decaying casserole dish lookalike, buried in your garden, or just somewhere in the middle of the street you walk down everyday to shop for groceries, or on the playground where your children play. You would probably live in constant fear, and isolation, since your friends would be too afraid to risk their lives to visit you. Such is the power of a small round landmine – a tiny iron cap filled with highly volatile explosive, which immediately ignites a larger amount of less volatile explosive, all wrapped in a case and topped up with a pressure plate.

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The scariest part? The estimated number is roughly 110 000 000 landmines scattered across more than 70 countries around the world. And since some of them are hard to detect, we won’t see a dramatic decrease in numbers any soon. The rate of demining – locating and removing mines, is 100 000 mines per year, while for every 5 000 removed one deminer is killed and two others get seriously injured. In the end, the estimated time to demine the whole world is 1 100 years, under the condition that no more mines will be planted meanwhile.

To tackle mine contamination, new technologies have to be invented. One such device, or rather a prototype had been recently successfully developed by Dr Liam Marsh from the University of Manchester. Unlike conventional mine detectors, which detect metals, this one can also “look under the ground” and tell what objects lie underneath it. This ability is useful, as many more recent mines contain a little or almost no metal and therefore can be easily looked over, presenting an even greater danger to deminers and civilians.

So, what’s the science behind this great enhancement?

Inside the newly produced prototype, a special type of ground penetrating radar (GPR) is contained. Normally, GPR devices send­off waves which enter the ground; and if there is an object below the ground, the waves will bounce off of it and go back to the device, where they are collected. The result is a beep suggesting the machine found something and that this something is lies at a certain depth. However, the upgraded GPR used in the new generation landmine detectors is a lot more sophisticated.

It is sensitive to all sorts of different materials, like plastics, and objects like rocks. In addition, the metal detecting technology used in the prototype is able to identify and classify different metal samples. All combined, the prototype system is able to recognize the nature of an object lying beneath the ground and determine whether it ́s a dangerous explosive box, which needs to be taken care of, or just a pair of keys on a keychain someone lost when going for a walk years ago.

Although it’s only a prototype, needing more development and testing before it can glimpse the light of the day, but it has a great potential in the future of “searching for casserole dish lookalikes”, increasing the rate, sufficiency and safety of clearance. This

clever machine can bring the fear, isolation and casualties involving innocent people closer to an end, so no one has to wait for 1 100 years to move around freely.

The Nuclear (Waste) War

Article by Rose Linihan, student of Xaverian College and winner of our 2017 Science Journalism contest.

The United Kingdom currently faces nuclear threat. And no, not that kind. There is in fact a potential energy crisis on its way, involving huge energy shortages and 100,000 tonnes of nScreen Shot 2017-05-26 at 14.33.25uclear waste, to be precise.

There are currently nine nuclear power stations here in the UK, providing 22% of our total electricity. The Government have decided they want nuclear power to continue to provide a portion of our energy, alongside other low-carbon options. The general public conception of nuclear power is notoriously bad, and yet nuclear power is very effective. It’s a low-carbon way of producing the energy needed to power everything in the UK, from our toasters to TVs, and radioactivity is all around us – there’s even radioactivity in bananas!

Nuclear energy itself is produced by a process called fission, whereby a very unstable isotope of an element called uranium is split into two smaller radioactive nuclei and 2 or 3 neutrons are released and lots of energy. In a nuclear reactor, uranium fuel is surrounded by graphite (material that used to be in pencils) moderators and keep the reaction under control by slowing the neutrons down so they’re at the optimum speed for a further reaction to occur. After it has done its job inside the nuclear reactor, this graphite is known as nuclear waste.

However, our current reactors are now old and so require decommissioning and replacing with new and more advanced models, or else there will be a national energy shortage. Which leaves the us with the problem of the 100,000 tonnes of radioactive nuclear waste. Not to mention 300,000 tonnes worldwide. The NDA (Nuclear Decommissioning Authority) is responsible for decommissioning nuclear waste and their present plan of how to do this is to wait 100 years and then bury the waste in a geological disposal facility. Another option is to go down a similar route to US whereby waste is shipped in containers and the stored in underground tunnels by machines. These options are both very expensive, costing a whopping £20 billion, not to mention being very time consuming and the fact that suitable geological sites are rare. So what do we do? Dump it at the bottom of the ocean? Bury it somewhere? Launch it into space? Or something else…

Alex Theodosiou is a post-doctoral research associate at Manchester University, working in the field of nuclear decommissioning as part of the Nuclear Graphite Research Group. They work as part of a consortium to come up with novel methods of tackling the nuclear waste crisis. Alex is currently researching the thermal treatment of nuclear graphite by reacting it with oxygen at high tempuratures to produce carbon dioxide. This carbon dioxide can then be managed using carbon capture techniques such as liquefication. Alex says ‘This will lead to a massive volume reduction in the graphite inventory and should help reduce overall costs involved with decommissioning, as well as reduce the lengthy timescales currently predicted.’ It could also have wider applications such as nuclear weapon disposal.

Alex’s laboratory work is small scale and involves using a few grams of nuclear grade graphite and heating it with a tube furnace under various conditions, before using a gas analyser to monitor the species formed. This lab data can then be transferred to an industrial scale by partner companies who use a plasma furnace and greater volumes of graphite, to produce results on 1000x the scale.

Alex and his colleages hope that together they can develop a commericially viable decommissioning strategy for the nuclear sector, to propose to the NDA to hopefully win the war against nuclear waste!