Playing with Solid State Benzene

molecular structure

Computational chemistry is a powerful interdisciplinary field where traditional chemistry experiments are replaced by computer simulations. They make use of the underlying physics to calculate chemical or material properties. The field is evolving as fast as the increase in computational power. The great shift towards computational experiments in the field is not surprising since they may reduce research costs by up to 90% — a welcome statistic during this financial crisis.

Keith M. Azzopardi (supervised by Dr Daphne Attard) used two distinct computational techniques to uncover the structure of a carcinogenic chemical called solid state benzene. He also looked into its mechanical properties, especially its auxetic capability, materials that become thicker when stretched. By studying benzene, Azzopardi is testing the approach to see if it can work. Many natural products incorporate the benzene ring, even though they are not toxic.

The crystalline structures of solid state benzene were reproduced using computer modelling. The first technique used the ab initio method, that uses the actual physical equations of each atom involved. This approach is intense for both the computer and the researcher. It showed that four of the seven phases of benzene could be auxetic.

The second less intensive technique is known as molecular mechanics. To simplify matters it assumes that atoms are made of balls and the bonds in between sticks. It makes the process much faster but may be unreliable on its own due to some major assumptions. For modelling benzene, molecular mechanics was insufficient.

Taken together, the results show that molecular mechanics could be a useful, quick starting point, which needs further improvement through the ab intio method.

 

This research was performed as part of a Masters of Science in Metamaterials at the Faculty of Science. It is partially funded by the Strategic Educational Pathways Scholarship (Malta). This Scholarship is part-financed by the European Union – European Social Fund (ESF) under Operational Programme II –Cohesion Policy 2007-2013, “Empowering People for More Jobs and a Better Quality Of Life”. It was carried out using computational facilities (ALBERT, the University’s supercomputer) procured through the European Regional Development Fund, Project ERDF-080 ‘A Supercomputing Laboratory for the University of Malta’.

Cockneys vs Zombies — Film Review

Film Review_NT

At a site in East London, two construction workers inadvertently unearth the tomb belonging to the late King Charles II. Upon entering the crypt, they are assaulted, bitten and unkilled by former plague victims. Meanwhile, brothers Terry (Rasmus Hardiker) and Andy (Harry Tread- away), with their cousin Katy (Mi- chelle Ryan), are planning a bank heist. The trio concoct this heinousness with a noble intent: saving their grandad’s (Alan Ford) retirement home from be- ing demolished by heartless property developers. But of course, everything goes pear-shaped when the entire neighbourhood is invaded by hordes of the undead.

Cockneys and zombies: that’s what the title promises and that’s exactly what it delivers. Given the self-conscious- ly schlocky title, you would expect a crudely-made, amateurish production,

the likes of which litter the internet. The truth is, thankfully, very different. Cockneys has quite a high production value. It’s not World War Z but footage of London enfolded in chaos and may- hem is rendered in good quality CG, as are the close-up shots of carnage.

Still, one problem with comedy zombie flicks is that they will forever be in the shadow of Edgar Wright’s masterful Shaun of the Dead (2004). Shaun was a perfect storm of comedy, horror, excellent production, inspired casting, and fortuitous timing. Just as everybody was trying to get his/her head around the seemingly dubious merits and immense popularity of tor- ture porn horror films (Saw and The Passion of the Christ were both released in 2004), in waltzed Messrs. Wright, (Simon) Pegg and (Nick) Frost who made everybody’s sides split with laughter.

Luckily, even though Cockneys vs Zombies is nowhere near as brilliant as Shaun, it still can hold its head high. Director Matthias Hoene and writers James Moran (Severance, 2005) and Lucas Roche touch upon, but don’t expand much, on the zombie-as-meta- phor angle. They just want to play it for laughs and get more hits than misses. The scene in which poor old Hamish (Richard Briers) is being chased by the notoriously slow-moving zombies is pure gold and West Ham United sup- porters can put their mind at rest that, even after death, the feud with Millwall still rages on. In an inspired scene, we are at last shown that even infants are not immune to a zombie infestation.

Cockneys is no (early) George A. Romero and does not aspire to be. It just wants you to relax, pop some corn, sip on soda, and enjoy a zombie-tour around the streets of East London.

Xemxija and Earthquakes

On February 22, 2011, a magnitude 6.3 earthquake struck the city of Christchurch, New Zealand, killing 181 people and causing widespread destruction. Curiously, this damage was not evenly distributed, even for areas right next to each other. This phenomenon is called the site effect and depends on the underlying geology.

Malta, unlike New Zealand, is not typically associated with earthquakes. The islands lack a seismic building code and many structures could be damaged with moderate shaking. Malta’s past records list several earthquakes that have damaged buildings and even caused some to collapse. Apart from not being reinforced, buildings have been built on less stable ground, which increases risk.

 

Setting up the Micromed Tromino, the instrument used to perform recordings of ambient noise measurements
Setting up the Micromed Tromino, the instrument used to perform recordings of ambient noise measurements

Sharon Pace (supervised by Dr Pauline Galea) investigated this effect in one test area — Xemxija, in the north of Malta. She studied how sites in Xemxija would respond to the energy from an earthquake by using a portable seismograph to record ambient noise (caused by sea waves, vehicular traffic, and other anthropogenic sources) at over 100 points across the village (pictured). The ground’s surface can be considered a vibrating platform, which can be shaken both by ambient noise as well as stronger waves from earthquakes. The ground may “resonate” at particular frequencies, or not at all, depending on the kind of rock or soil layers making up the top 30 to 50 metres. Analysis of ambient noise shows if such resonance phenomena exist, how they are related to the local geology, and how this would translate into actual earthquake shaking.

 

Resonant peak frequency distribution patterns around the Xemxija area
Resonant peak frequency distribution patterns around the Xemxija area

At Xemxija, the study confirmed that the presence of clay (whether at the surface or buried) does amplify the grounds motion at certain frequencies.  The results match previous studies in other areas, but this research went further by constructing geological models that can determine the ground’s underlying structure .

Taken together, the survey shows areas in Xemxija that might need extra support to survive future earthquakes and prevent deaths. Xemxija is not the only area with soft clay geology, the urbanised area of Mellieħa and historic citadel Mdina are built on top of similar structures. Considering the importance of these areas means that more studies are needed to better understand the structure of Maltese buildings and how they would respond to earthquakes.

 

This research was performed as part of a Masters of Science in Physics at the Faculty of Science. It was partially funded by the Strategic Educational Pathways Scholarship (Malta). This scholarship is part-financed by the European Union — European Social Fund (ESF) under Operational Programme II — Cohesion Policy 2007 – 2013, “Empowering People for More Jobs and a Better Quality of Life”.

Scientific beauty of diamonds

Laptops and mobiles are smaller, thinner, and more powerful than ever. The drawback is heat, since computing power comes hand in hand with temperature. Macs have been known to melt down, catch fire and fry eggs — PCs can be even more entertaining. David Grech (supervised by Prof. Emmanuel Sinagra and Dr Ing. Stephen Abela) has now produced diamond–metal matrix composites that can remove waste heat efficiently.

Diamonds are not only beautiful but have some remarkable properties. They are very hard, can withstand extreme conditions, and even transfer heat energy faster than any metals. This ability makes diamonds ideal as heat sinks and spreaders.

The gems are inflexible making them difficult to mould into the complex shapes demanded by the microelectronics industry. By linking diamonds with other materials, new architectures can be constructed. Grech squashed synthetic diamond and silver powders together at the metal’s melting point. The resulting composite material expanded very slowly when heated. The material could dissipate heat effectively, and was cheaper and simpler to produce than current methods — a step closer to use on microchips.

Grech’s current research is focused on obtaining novel types of interfaces between the diamond powders and the metal matrix. The new materials can improve the performance of heat sinks. New production techniques could help make these materials. By depositing a very thin layer of nickel (200 nanometres thick) on diamond powders using a chemical reaction, the gems would form chemical bonds with the layer while the metal matrix would form metallic bonds. The material would transfer heat quickly and expand very slowly on heating. A heat sink made out of this material would give us a cooler microprocessor and powerful electronics that does not spontaneously catch fire — good news for tech lovers.

nanoShots

 

This research was performed as part of a Bachelor of Science (Hons) at the Faculty of Science. It is funded by the Malta Council for Science and Technology through the National Research and Innovation Programme (R&I 2010-25 Project DIACOM) and IMA Engineering Services Ltd. 

Future-Safe Malta

Words by Prof. Saviour Formosa
“Extreme weather leaves Mediterranean countries picking up the pieces. Egypt and Lebanon were the hardest hit with over 1.2 million people displaced overnight. Malta didn’t fare much better. The authorities have reported over 2,300 dead or missing, thousand injured and 74,000 persons displaced. Power cuts have been reported all over the island after Turbine Two tripped at the Delimara Power Station. Enemalta have not replied. The islands have taken a major blow to their infrastructure. Debris has been reported 1 km away from the coasts. The AFM and emergency responses were immediately dispatched and are starting to clear arterial roads. Insurance companies are still counting the costs. Valletta, Floriana and parts of Isla were protected from the storm surge by centuries-old Knight’s fortifications. The following localities have been affected: Birgu, Bormia, Kalkara, Marsa, Gzira, Msida, Pietà, San Giljan, Sliema, Ta’Xbiex, Xghajra, Birzebbuga, Marsascala, Marsaxlokk, Xlendi and Marsalforn. “

The above cutout could become reality if a Category 3 storm lashes Malta with 178 to 208 km per hour winds. The chances are minimal but too probable to ignore, since in 1995 a similar storm formed close to the Maltese Islands followed by others in 1996, 2006, and 2011.  Below are two scenarios that compare Malta as it currently stands against an island with a solid disaster management plan.

 [ SCENARIO 1 – AN UNPREPARED ISLAND]

The emergency forces have been inundated with calls for help and have few plans to operate a workable rescue effort. Key personnel were lost at home or while rushing to the scene, since the infrastructure has been knocked out, paralysing the island.  Power surges or power cuts have caused fires all over the Islands creating an apocalyptic scenario. With the storm still raging, the lack of a back-end ICT network has rendered communication near impossible.

 [ SCENARIO 2 – THE IDEAL SCENARIO]

A fleet of small aerial drones is monitoring the disaster. The authorities are using them to identify the hardest hit areas and map out corridors that allow access on the ground. Emergency vehicles are being deployed safely. Services will be redeployed after safety assessments and clearing of the main infrastructure. Paramedics, NGO rescue teams, and armed forces help move people to safer grounds and carry out rescue operations. Community buildings on higher ground are converted into temporary shelters. In turn, decision-makers are kept informed using an Emergency Room for effective relief.Continue reading

Labs in solution

Imagine the smallest thing you possibly can. The eye of a needle? A human hair? A particle of dust? Think smaller, something you cannot even see, something on a molecular scale. Now imagine that molecule has the potential of a whole laboratory. This dream is now becoming a reality.

In recent years, the field of molecular sensors has grown into one of the most ground-breaking areas in Chemistry. Molecular sensors are compounds that can detect a substance, or unique mixture of substances, and provide an easily detectable output. Usually this is a change in the absorption of ultraviolet or visible light, or in the emission of Fluorescence. In other words: colours!

John Gabarretta (supervised by Dr David Magri) created a simple example of these fluorescent molecular sensors. The molecule was based on the Fluorophore-Spacer-Receptor model, where the ‘output’ part of the molecule (the fluorophore — a structure which shines light) is separated from the ‘input’ part (the receptor — a structure which is sensitive to a particular substance, such as acidity or a metal ion) by an intermediate spacer, whose main function is to link these two components together. The model means that a molecule can detect a chemical and respond by shining light or not. The process gives information about the chemicals in a solution.

The molecule’s structure, based on the Fluorophore-Spacer-Receptor model (shown as a scheme), allowed for a bright blue fluorescence when exposed to Ultraviolet light
The molecule’s structure, based on the Fluorophore-Spacer-Receptor model (shown as a scheme), allowed for a bright blue fluorescence when exposed to Ultraviolet light

 

The molecule was made by a two-step synthetic route (which took several attempts and resulted in several different colours), and its behaviour was tested by dipping into an acid. In water the molecule was switched ‘off’, but quickly turned ‘on’ in an acidic solution by giving a bright blue light when exposed to ultraviolet light (UV) — a pretty satisfying sight!

Molecular sensors have some very advanced applications — the pioneer A. P. de Silva said that there is room for a “small space odyssey with luminescent molecules”. This odyssey includes some that detect substances such as sugars.

While very advanced systems are approaching chemical computers, since they have multiple inputs and use Boolean Logic, the so-called ‘Moleculator’ or ‘gaming tic-tac-toe’ systems. The future is bright (if you pardon the pun) and with more complex structures more possibilities will appear; the molecular laboratory may become a reality detecting diseases or toxins in no time at all.

 

This research was performed as part of a Bachelor of Science (Honours) at the Faculty of Science.

Insects in Malta

Insects are vital. Insects also cover the planet, with local research showing that there might be over 6,000 species — a wonderful world awaits. Find out about the incredible world of insects in Malta!

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Valletta’s Digital Layer

Matthew Mamo
Matthew Mamo

Dérive Valletta is an initiative by digital art student Matthew Mamo (supervised by Dr Vince Briffa) aimed at increasing the visibility of our capital city’s museums and cultural institutions using augmented reality.
Augmented reality has a host of possibilities to allow people to interact with art and through this art the city itself. Inspired by the work of Israeli artist Yaacov Agam, the digital visuals featured in Dérive Valletta require the user to move around the objects being scanned in order to view the content.
Possessing its own cohesive brand and identity, this initiative is ultimately intended to contribute towards the creation of a digital cultural infrastructure within Valletta prior to 2018. Being a digital layer laid over the real world there will be no negative impact on this UNESCO World Heritage Site’s unique built environment.
The brand’s aesthetics were kept minimalistic to create an identity that can be incorporated into Valletta in an unobtrusive manner while endowing the initiative with a contemporary image. Minimalism is reflected in the restrained colour scheme and use of clean sans-serif typefaces.

The research was undertaken as part fulfilment of an MFA in Digital Arts and partially funded by the Strategic Educational Pathways Scholarship (Malta). This Scholarship is part-financed by the European Union — European Social Fund (ESF) under Operational Programme II — Cohesion Policy 2007–2013, “Empowering People for More Jobs and a Better Quality Of Life”.

Choices, Choices, Choices…

Taking the right decision can be a very challenging and daunting process. Designing a mobile phone, a makeup case, or even a pipe needs engineering teams to continuously make important choices quickly. Lawrence Farrugia (supervised by Prof. Jonathan C. Borg) developed a framework that helps engineers evaluate concepts and take these decisions practically. In a typical design process, the design team generates a number of different concepts that fulfil what is needed from the product. These design concepts are then evaluated against conflicting evaluation criteria. Criteria are chosen from the life cycle of the product and can include cost, quality, ease of use, and recyclability (pictured). Evaluation determines the concept chosen for further development.
Sketch

Although there are design tools that are intended to support engineering design teams in decision making, the reality check is that these tools are rarely used. Such tools are typically too impractical to employ in the real world. Due to the ever increasing complexity of products and the importance of early decision making, this research recognised the need to provide engineering design teams with a practical yet reliable support system.
Farrugia’s research was carried out at the Concurrent Engineering Research Unit (CERU) within the Faculty of Engineering. The framework he developed aids design teams to analyse and rank multiple design concepts against several conflicting evaluation criteria. The proposed framework was then implemented into a prototype computer aided design (CAD) tool named ACADEMI (pictured).

Figure 2

The tool developed by Farrugia allows for design concepts to be mathematically appraised and ranked automatically. The user inputs the various evaluation criteria and the best design is shown in a very short time. This ranking helps the design team rapidly figure out which design concepts should be developed. After the framework and tool were developed the research work was evaluated in the field by engineers from industry and academia. Most industry personnel said that they would be willing to adopt the computer tool in their daily professional work. ï

More information about the research work may be accessed through: www.academi.co.nr

This research was performed as part of an M.Sc. (Research) in Mechanical Engineering at the Faculty of Engineering. This research was partially funded by the Strategic Educational Pathways Scholarship (Malta). This Scholarship is part-financed by the European Union — European Social Fund (ESF) under Operational Programme II — Cohesion Policy 2007–2013, ‘Empowering People for More Jobs and a Better Quality Of Life’.

Keeping heart attacks on hold

Heart attacks and strokes kill millions every year. Most are caused by blockages to blood vessels. Vessels can be pried open by heart stents, tubular devices that are inserted and inflated to prevent vessels from collapsing or blocking. Stents incur many problems ranging from flaring at the edges to fracturing to unexpected shrinking. All lead to complications, further surgery, and even death.

Luke Mizzi (supervised by Prof. Joseph N. Grima, Dr Daphne Attard, and Dr Ruben Gatt) has studied existing stent designs to identify their weaknesses and is currently studying novel designs that overcome these problems. He used computer simulations to replicate the stresses current stents experience in the human body. These stents performed well in response to inflation and bending. However, shortening still occurs and they do not expand uniformly leading to flaring at the edges.

Mizzi found which current designs fared well but no design had all the features needed by heart stents. Crowns with a zigzagging structure allow for high expandability while S-shaped connections between crowns allow for high flexibility.

Mizzi who forms part of the Metamaterials Unit is designing new stent geometries that build on these features incorporating them all and improving stent performance. The next step for these researchers are designs that support part of the throat or oesophagus to continue saving lives.

 

This research was performed as part of Doctoral Studies at the Faculty of Science at the University of Malta. It is funded by the Malta Council for Science and Technology through its R&I programme. This project is in collaboration between the University of Malta, HM RD Ltd, part of the HalMann Vella Group of Companies, and Tek-Moulds Precision Engineering Limited.