Education

Ideal Gas Law Simulation

Merlot chemistry - 29 July, 2014 - 10:17
An effective tool to help students learn about all aspects of the ideal gas law. One of the best web gas law simulations.
Categories: Education

Assessing Blood Pressure

Merlot chemistry - 29 July, 2014 - 10:17
This learning module presents the proper technique and common errors associated with assessment of blood pressure. The information is targeted at new learners in the clinical and health sciences and can serve as a review for current practitioners. The program includes audio of blood pressure sounds, interactive simulations, and self-assessment tools.
Categories: Education

DNA from the Beginning

Merlot chemistry - 29 July, 2014 - 10:17
DNA from the Beginning is an animated tutorial on DNA, genes and heredity. The science behind each concept is explained using animations related to DNA topics, an image gallery, video interviews, problems, biographies, and links related to DNA. There are three sections, Classical Genetics, Molecules of Genetics and Organization of Genetic Material. Key features are the clear explanations of classical experiments and the excellent photographs of researchers and their labs.For information and credits on the development of DNA from the Beginning, go to http://www.dnaftb.org/dnaftb/credits.html
Categories: Education

VR Molecules

Merlot chemistry - 29 July, 2014 - 10:17
VR Molecules presents dynamically and interactively the vibration and rotation modes for 24 molecules (out of a more extensive list) containing up to twelve atoms. It allows the user to create and save on his or her hard disk documents containing, much in the same way as Power Point presentations, up to 10 "pages״, each featuring one or two molecules with specific parameters (viewpoint, active modes, etc.). These presentations can be made available through the Internet, with optional sound and text explanations associated with each page.The latest, augmented version of VR Molecules, called VR Molecules Pro 1.1, is available online as well as in a stand-alone version (Mac and Windows). To view a video of the award winning author, go to View VR Molecules - Chemistry Award Winner 2007 video VR Molécules est un logiciel de simulation (en ligne et en mode local) permettant de visualiser et d'explorer les modes de vibration et de rotation des molécules (24 molécules sont disponibles). Il peut tout aussi bien être utilisé par le professeur pour préparer des démonstrations en classe, intégrer des animations (interactives ou non) dans ses documents HTML, que par les étudiants pour revoir les démonstrations présentées en classe et explorer par eux-mêmes la vibration et la rotation des molécules.La plus récente version (1.12) de VR Molécules, est accessible en deux versions : en ligne et en mode local (à télécharger, pour Mac et Windows).
Categories: Education

Neuroscience for Kids

Merlot chemistry - 29 July, 2014 - 10:17
The entry point to an extensive site concerning the nervous system and neuroscience. The site includes descriptive materials, experiments, activities, links to articles, resources for teaching neuroscience, and a listing of Internet resources related to the neurosciences.
Categories: Education

Virtual Chemistry Laboratory

Merlot chemistry - 29 July, 2014 - 10:17
Here's your chance to mix chemicals without wearing safety goggles. You won't spill any acid on the spectrometer in this lab. Choose solutions from the vast database and mix 'em together till the cloned cows come home. Marvel as the chemical solutions react in real time.
Categories: Education

PhET - Physics Education Technology at the University of Colorado

Merlot chemistry - 29 July, 2014 - 10:17
A collection of simulations and virtual labs focusing on first-year college physics. An interview with the award winning author can be found in About us at Phet VideoPhET provides fun, interactive, research-based simulations of physical phenomena for free. We believe that our research-based approach- incorporating findings from prior research and our own testing- enables students to make connections between real-life phenomena and the underlying science, deepening their understanding and appreciation of the physical world. To help students visually comprehend concepts, PhET simulations animate what is invisible to the eye through the use of graphics and intuitive controls such as click-and-drag manipulation, sliders and radio buttons. In order to further encourage quantitative exploration, the simulations also offer measurement instruments including rulers, stop-watches, voltmeters and thermometers. As the user manipulates these interactive tools, responses are immediately animated thus effectively illustrating cause-and-effect relationships as well as multiple linked representations (motion of the objects, graphs, number readouts, etc.) PhET Interactive Simulations, University of Colorado, http://phet.colorado.edu
Categories: Education

Physlets

Merlot chemistry - 29 July, 2014 - 10:17
Educational physics applets designed to be scripted in JavaScript for use in quizzes, homework problems, and Just in Time Teaching activities. Includes applets that can be used in a wide range of classes and at different levels.
Categories: Education

Music Acoustics

Merlot chemistry - 29 July, 2014 - 10:17
The acoustics of musical instruments and the voice. The "Basics" directory introduces and explains general concepts. There are "Introduction to the Acoustics of [instrument name]״, data bases, technical material, web services (including a hearing test) and a FAQ.
Categories: Education

MecMovies

Merlot chemistry - 29 July, 2014 - 10:17
MecMovies is an extensive collection of examples, theory, and games designed to complement the entire Mechanics of Materials course. The software features impressive graphics and animation that are highly effective in visually communicating course concepts to students. Special emphasis is placed on developing the learner?s understanding and proficiency in basic concepts and skills through interactive exercises and games. Classroom implementation of the software has produced improved student performance and more positive student attitudes regarding the Mechanics of Materials course. To see a video with the award winning author, go to View MecMovies video
Categories: Education

Journal cover art that will brighten your day

Chemistry World blog (RSC) - 24 July, 2014 - 16:22

Guest post from Tom Branson

After browsing the recent chemical literature, I have finally found enlightenment. I have quite simply been left in a trance after witnessing a recent cover from Chemical Society Reviews.

A colour explosion

There’s so much colour in this image I just don’t know where to begin. So let’s start by taking a look at that green globe. Surely a prophecy of a future world when green chemistry has finally paid off and this development also seems to have led to a plethora of plant life sprouting from the Earth. Holding that planet aloft are two pairs of caring hands. An adult gently holds a child’s tiny hands and together they embrace this new future. Peace and love and chemistry, what more could you ask for?

And what about that background? Wow, they didn’t hold back with the colour palette. With some journals still charging for colour figures I bet these guys always get their money’s worth.

So there are adult hands, clasping a child’s hands, supporting the world, sprouting a bouquet of flowers, in front of a mega-rainbow, oh it’s almost enough to make me quit science and run off to join a cult.

Seriously though, the cover is a wonderful attempt to highlight sustainability and forward thinking, something that is sadly all too often lacking in modern society. The author of the paper, Jinlong Gong of Tianjin University, China, tells me of his hope that ‘this cover can call up the attention of people to consider more about the future of our world’. Nicely said.

There are not really many clues in the image as to what the published science is about but the keen eyed among you may have spotted a few water droplets on the plant leaves. Was the printer simply too close to the water cooler at Chem. Soc. Rev. headquarters, or is this paper all about solar water splitting? Aha, the latter of course.

Photocatalysis

The cover art is for a review article about a really promising solution for solar energy; tantalum-based semiconductors. Visible light can be absorbed by these semiconductors and used in solar water splitting, converting solar energy into chemical energy. The team from China highlight that while this type of photocatalyst is still far away from use in practical applications, improvements in the efficiency and stability of these systems give hope to the tantalum-based community.

Those wanting to know more about this tantal(um)ising hope for the future can access the article over at Chem. Soc. Rev.

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Categories: Education

Meet our guest bloggers – Tom Branson

Chemistry World blog (RSC) - 24 July, 2014 - 16:00

I recently completed my PhD at The University of Leeds where I was investigating protein-carbohydrate interactions and protein assembly. I’m a synthetic biologist now working on biomolecular interactions, based in The Netherlands. I also blog about science communication issues and chemistry trivia over at Chemically Cultured.

Here at Chemistry World, I will be writing a regular blog series to highlight some of the best academic journal covers – the images that grace the front of those magazines we all paw through. Many of you might think that academic journals are a place where only serious facts and tables of data find their home, but, at the very start of many journals lies an artistic outburst.

These journal covers are a great place for researchers to highlight their work and at the same time, show off their artistic skills. Many covers have caught my eye over the years and they deserve to be promoted for the talent and, more than often, eccentricities that show in these designs. Imagination, creativity and communication are core principles in the world of science and all this comes to the fore on the front cover of our favourite periodicals.

 

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Categories: Education

YMS winners

Chemistry World blog (RSC) - 10 July, 2014 - 14:50

The Royal Society of Chemistry’s 3rd Younger Members Symposium (YMS2014) was held towards the end of June at the University of Birmingham. Kicking off the day was Lesley Yellowlees who gave an inspirational plenary lecture covering her research and career path, in one of her final acts as RSC president. ‘Aspire to be the president of the Royal Society of Chemistry – it’s the best job ever,’ she told the audience. She also shared lessons she had learned over the years including: develop your own style, grasp opportunities and find ways of dealing with difficult colleagues.

Jamie Gallagher, the University of Glasgow’s public engagement officer, energised everyone after lunch by talking about his work and why public engagement makes you a better academic. Public engagement doesn’t necessarily have to involve standing on a stage like Jamie does on a regular basis. He gave some fantastic advice on the many schemes and organisations to get involved with such as Cafe Scientifique and your local RSC section.

Both excellent talks but the real meat of the day was comprised of poster sessions and seminars where attendees shared and quizzed each other on their research. Chemistry World was delighted to sponsor its first ever poster prizes in the inorganic and materials category. And the winners were…

First prize went to Giulia Bignami from the University of St Andrews.

Giulia Bignami: ‘The research work described in my poster focuses on the synthesis, according to the assembly-disassembly-organisation-reassembly (ADOR) method, of 17O-enriched UTL-derived zeolitic frameworks and their subsequent characterisation through 17O and 29Si solid-state NMR, involving both 1D and 2D spectral techniques, in magnetic fields ranging from 9.4T to 20.0T. We showed how 17O and 29Si NMR-based structural investigation proves extremely helpful to gain insights into the synthetic process employed, thus shedding light on the way new and targeted zeolitic structures could be achieved.’

Second prize went to Gurpreet Singh from the University of Central Lancashire.

Gurpreet Singh: ‘The aim of the research is to find new ion exchange materials for use in the nuclear industry. The problem with some of the current ion-exchange materials is that they are not stable to the conditions found in the waste pools at nuclear sites. Zirconium phosphates have been proposed to be more stable and by doping other metals into the structure in place of zirconium it might be possible to create new materials which have increase selectivity for the cations of interest (strontium and caesium). The work presented shows that yttrium can be successfully introduced into the structure of alpha-zirconium phosphate and the ion-exchange experiments are on-going.’

Third prize went to Daniel Lester for a poster about work he did at the University of Sussex.

Daniel Lester: ‘In the field of VOC (volatile organic compound) degradation by photocatalysis, P25 (powdered TiO2 of 75% anatase 25% rutile composition) is often seen as a benchmark material. However, in the continuous flow reactors used in industry, a powdered catalyst is impractical to use. I therefore aimed to create several supports for TiO2, which not only improved the physical durability of the catalyst but also improved the photocatalytic efficiency. Glass wool acted as a wave guide, TiO2 nanofibres served as photoactive supports and zeolites provided an electron sink to decrease hole-pair recombination and to increase contact time between the active species (TiO2) and the target VOC.’

Congratulations to all of our poster winners and to the organisers for an enjoyable symposium.

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Categories: Education

Open notebook science – memorial symposium for Jean-Claude Bradley

Chemistry World blog (RSC) - 3 July, 2014 - 16:49

Guest post by Antony Williams, chemconnector.com

Jean-Claude Bradley was a chemist, an evangelist for open science and the father of a scientific movement called Open Notebook Science (ONS). JC, as he was commonly known in scientific circles, was a motivational speaker and in his gentle manner encouraged us to consider that science would benefit from more openness. Extending the practice of open access publishing to open data, JC emphasized the practice of making the entire primary record of a research project publicly available online, primarily using wiki-type environments, and in so doing set the direction for what will likely become an increasingly common path to releasing data and scientific progress to the world.

I first met JC as a PhD student at Ottawa University, Canada, when I was the NMR facility manager and was responsible for scientists and students in their research. JC entered my lab one day to ask for support in elucidating the chemical structure for one of his samples and what began that day was a scientific relationship and friendship spanning over two decades. As one of the founders of the ChemSpider platform now hosted by the Royal Society of Chemistry, JC and I reinvigorated our friendship around a drive to increase openness of chemistry data, access to tools and systems to support chemistry, and simply to make a difference.

From too many conversations I know that some of the basic tenets of his views were shunned by many scientists in the early days of his shift towards ONS. Despite people being interested in his approach only a fractional minority of scientists fully supported ONS by being active participants. Through his activities in curating and validating scientific data, engaging chemical vendors in opening some of their datasets, and his demand that everything he did in science be open, he has produced a legacy that will continue to have influence for years to come. Right now, data he released to the public domain is being worked up into open models for release to the community. The Spectral Game that he dedicated efforts to will be supported and enhanced to assist in teaching spectroscopy. In recognition of his work and to celebrate JC’s contribution to science, a memorial symposium will be held in his honour at Cambridge University on 14 July and, of course, is OPEN to everyone.

Jean-Claude Bradley was a scientific leader, an evangelist for open science and a wonderful man. He will be missed but his legacy will survive and flourish.

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Categories: Education

June 2014: Diversity Special

Royal Society R.Science - 30 June, 2014 - 17:01

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Categories: Education

Making sense of chemical stories

Chemistry World blog (RSC) - 9 June, 2014 - 16:56

Guest post from Lauren Tedaldi, Sense About Science

Have you noticed plastic products labelled as ‘BPA-free’*, heard that Coca-Cola recently removed a specific vegetable oil from its US products** or do you remember the time when there were no blue smarties***? When companies change the way they produce common, long-standing products, we reasonably assume that they have good reasons for doing so: we all know the adage ‘If it ain’t broke, don’t fix it’ right? In reality, companies can be forced to act on the modified version: ‘If enough people think it’s broken— even if there is no evidence that it is—then you’d better fix it if you want to keep selling it.’

Consumer pressure is a force to be reckoned with. Owing in large part to the internet, consumers now have more access to information than ever before. People can search almost every online discussion ever had about a particular product or additive before making a decision. While this has the potential benefit of making people better informed, the flip-side is that the internet and media are littered with misconceptions, myths and pure fallacies, which come up time and time again. For example, the idea that you can live a ‘chemical-free’ life is used by many food-producers; and ‘natural ingredients’ is used as a synonym for ‘good’ in cosmetics and toiletries. But every single thing you come into contact with is made from chemicals: your book, your iPad, yourself! What’s more, not all naturally occurring substances are good for you: the pesticide strychnine, the highly toxic poison for which there is no antidote, is entirely natural – it’s isolated from the strychnine tree.

At Sense About Science, we spend more of our time responding to chemical scare stories, helping journalists pre-empt this narrative, than almost any other single issue. We regularly work with scientists frustrated at the hype around their research. This has changed relatively little over the 10-plus years we’ve been working to tackle chemical myths (Making sense of chemical stories was first launched in 2006). There has been some change: beauty journalists are now more aware and seek advice from a toxicologist or cosmetics scientist more often; and we regularly see detox diets and products debunked across national press and magazines. But we continue to see high profile chemical scares hitting the headlines.

When we see recurring misinformation we respond with our public guides. Teachers and midwives and others who are helping people cut through the noise, as well as journalists and policy makers – who the original guide was written for – have been requesting copies of the guide. So on 19 May 2014 we launched a new edition of Making sense of chemical stories. By capturing insights from the chemists and dieticians who developed the guide, we address six common chemical myths. Armed with these six points, anyone can critique the chemical stories they see:

  1. You can’t lead a chemical-free life
  2. Natural isn’t always good for you and man-made chemicals are not inherently dangerous
  3. Synthetic chemicals are not causing many cancers and other diseases
  4. “Detox” is a marketing myth
  5. We need man-made chemicals
  6. We are not just subjects in an unregulated, uncontrolled environment, there are checks in place

In the guide, we look at common consumer issues to debunk widespread myths. Why are labels such as ‘no artificial ingredients’ or ‘additive free’ seen as good things on our products? Dr Paul Illing, a toxicologist, talks about why additives in food are useful in some cases:

‘Additives have been around for centuries. Many agents that are essential for commercial food preparation and storage have their analogues in the kitchen. Caramel (E150a), a colouring agent, can be made at home by heating sugar. Some additives are clearly beneficial: in 1941 calcium was added to flour to prevent rickets; and antioxidants (necessary to prevent the fats in all prepared foods involving meat or pastry from going rancid) include ascorbic acid (vitamin C, E300) and the tocopherols (vitamin E, E306-309).’

 The guide highlights to consumers that products are not inherently better just because they don’t contain additives.

Professor Danka Tamburic, a specialist in cosmetic science, goes on to explain that we also need certain additives in cosmetics:

‘Most cosmetics and toiletries contain water, hence make a good substrate for growing microbes (eg bacteria or fungi). Proper preservation of cosmetics and toiletries is a necessity, not a choice. Bacterial cells are too small for the naked eye to detect, but if there are enough of them in the product, they may cause skin infections and other problems, especially if the skin is already damaged (cut, bruised or sore). Contaminated products could cause ye infections and, in extreme cases, blindness.’

We urge people, next time you are thinking about paying more for something simply because it’s ‘additive-free’, ‘100% natural’, or ‘detoxifying’, you might want to stop and think whether it’s worth paying a premium for a chemical misconception.

 

The full version of the guide can be found here or visit Sense About Science to see more of our public guides that can help you make evidence-based decisions about the products you choose to buy.

*Bis-phenol A (BPA) is a chemical that is used in manufacturing clear rigid plastic, like water bottles, and there is no compelling evidence that the level of exposure from plastic bottles and packaging is damaging to health

**Coca-Cola has removed brominated vegetable oil (BVO) from its US products (it is not in their European products) owing to consumer pressure. BVO is often incorrectly linked to the toxicity and accumulation data from brominated flame retardants

***Nestlé removed the colouring Brilliant Blue (E133) and replaced it with a natural colourant called spirulina after consumer pressure to go ‘artificial additive-free’. There is no strong evidence for a link between E133 and hyperactivity, and spirulina itself has adverse effects at high concentrations. However, it is often preferred as the natural choice

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Categories: Education

The music of molecules

Chemistry World blog (RSC) - 4 June, 2014 - 15:36

What do molecules sound like? In chemistry, we rarely take advantage of the full panoply of senses available to most humans. Although, as Phillip Ball wrote in January this year that ‘chemistry is the most sensuous science … vision, taste and smell have always been among the chemist’s key analytical tools’, we now sensibly avoid using one of these (molecular gastronomists aside, I’m not aware of a lab that encourages tasting of samples) and rarely, if ever, take advantage of our other senses: touch and hearing.

For researcher David Watts, the idea of listening to organic molecules had been ‘languishing in a notebook’ since he first visualised compounds as tiny stringed instruments. As each molecule has a vibrational signature, it should be possible to convert them to characteristic musical tones. David realised that data from Fourier transform infrared spectroscopy (FTIR) should provide all the necessary information, ‘the frequency and amplitude of absorption in the bonds’, albeit in the wrong format for direct conversion to sound. He designed a second step to create audible sound waves from those vibrations. ‘If an inverse Fourier transform is performed then the FTIR spectrum can be converted into the time/amplitude domain and the vibrations of the molecules heard.’

You can hear his results online at The sounds of chemical molecules. The sounds themselves vary between a telephone tone and the sort of discordant sounds used to create tension in budget science fiction, but making beautiful music was never the aim. This was part curiosity and part proof of principle, but Watts can already see a number of applications.

‘Having the sound of a molecule allows you to perceive it using our auditory sense,’ he told Chemistry World. ‘This alone in my view justifies the experiment.’ Most people, except perhaps those with perfect pitch, would not be able to discern structural/functional information from a static tone, but Watts argues that this isn’t the point – sound adds an additional element to a researcher’s relationship with molecules. ‘Maybe this auditory chemical perception ability can be learnt with practice and be useful for organic chemists as an additional way for them to connect or understand their molecules. A particularly interesting idea is in the auditory monitoring of a chemical reaction, maybe an online FTIR monitoring system could provide reaction progress feedback or offer insight into reactions and their intermediate states. The use of the extra sense of hearing allows you to watch and perform an experiment whilst listening to its progress.’

Giving a voice to a molecule is fairly straightforward. ‘Sounds can be created for any molecule providing a digital spectrum is available,’ says Watts. Although the exact applications are still unclear, it may be wise to start compiling the music of the molecules now, so that we’re ready when those uses do become apparent. ‘In my opinion, the auditory representation of the molecule should be obtained for all molecules and included in online databases as extra information for familiarization purposes and potential future uses,’ says Watts.

As a proof of concept, Watts’ demo proves that accessing an additional sense is well within the realms of possibility. The sine waves he generates may be somewhat grating, and I’m not sure I could bring myself to listen to them throughout the process of a reaction, but they’re just a first step. Next would be to find a waveform that is more pleasing to the ear, or modulate it with additional data. Perhaps temperature could set a rhythm, syncopated by pressure. Soon, we could all be dancing to a molecular melody.

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Categories: Education

Schrödinger’s water for the perfect cup of coffee

Chemistry World blog (RSC) - 30 May, 2014 - 11:33

How a computational chemist and an understanding of water helped a coffee shop owner to become the 2014 UK Barista Champion, set to take on the world. Guest post by Chris Hendon.

Christopher Hendon and Maxwell Colonna-Dashwood at Colonna and Smalls, Bath
© tomsmith photography

Brewing coffee might be the most practiced chemical extraction in the world. But within this process there are many variables, all of which dictate the flavour of the resulting coffee. I’ve summarised just a few of them here:

Variable Effect
Bean origin Not all beans have the same chemical composition.
Bean roast The chemical composition of the coffee bean changes throughout the roasting process.
Size of coffee grindings A consistent particle size is important as the higher the surface area, the faster the extraction.
Dry mass of coffee grindings A different extraction composition.
Temperature of extraction The temperature dictates both the rate and composition of the extraction.
Pressure of extraction Has a similar effect as temperature.
Time of extraction Increasing extraction time allows for a greater extraction.
The water This variable is less obvious, but it is clear that the chemical composition of water (i.e. dissolved ions) play a very important role.

 

Analysis of extracted coffee by gas chromatography–mass spectrometry (GC-MS) suggests that the average coffee bean contains upwards of 500 chemical compounds, excluding all of the heavy cellular material. Of this complex array, the bean is primarily a mixture of weakly acidic molecules, and the weaker acids are more desirable. A ‘bad coffee’ can be the result of any combination of the aforementioned variables going awry.

Maxwell Colonna-Dashwood, 2014 UK Barista Champion and co-owner of the specialty coffee shop Colonna and Small’s, in Bath, UK, carefully controls most of these variables. He grinds beans to a consistent particle size, weighs the dry mass, uses a constant temperature and pressure for extraction (which  he dials in for each bean on the day), and defines the extraction by the mass of the extracted coffee. However, it’s almost impossible for him to control the chemical composition of the incident water. Water’s ionic content fluctuates dramatically depending on region and quantity of rain – and it rains a lot in England. The coffee industry has designed some ways to deal with this problem, with filtration units and vague guidelines on what chemical composition to aim for.

The coffee industry has concluded that an ionic concentration of 150–300 parts per million (ppm) is ideal for coffee extraction. But that is inherently flawed; water could contain 150ppm of HCl and would certainly not taste very nice. Conversely, water could contain 150ppm of NaHCO3, which might make you burp as the acid/base reaction in your stomach rapidly releases gaseous CO2. So in search of the perfect coffee, it would be wrong to accept these guidelines without some thought as to the impact of different chemical compositions. Unfortunately, not every local barista has access to an atomic absorption spectrometer (we do). Instead this measurement is often collected (if at all) using an ionic conductivity probe, which makes two absolutely fatal assumptions:

  1. The ratio between dissolved ions (Ca2+, Mg2+, Na+, H+, HCO3-, CO32- etc) is approximately constant
  2. The ionic conductivity of all ions is approximately the same

Both of these statements are incorrect. For instance, in Bath there is much more Ca2+ present than Mg2+ (approximately 300ppm:5ppm, respectively); but in Melbourne the Ca2+:Mg2+ ratio is approximately 20ppm:20ppm. Secondly, the conductivity of an ion is dependent on, among other things, the size and charge of the ion.

Colonna-Dashwood is certainly right in challenging this accepted guideline, but what interaction do these molecules have with coffee particulates and more importantly, does it even matter?

Yes. It matters, a lot.

Christopher Hendon and Maxwell Colonna-Dashwood at Colonna and Smalls, Bath
© tomsmith photography

As is often the case in science, it was an element of serendipidy that brought me into the picture. I’m a computational chemist at the University of Bath, and overheard this discussion while waiting for my coffee. I thought I might be able to contribute to the problem, at very least help to rationalize this in terms of quantum mechanics. I had learned from fundamental chemistry that electron-rich motifs interact with electron deficient motifs. Essentially all molecules in coffee feature a heteroatom (an electron-rich motif), which should interact strongly with dissolved cations in water. Dissolved anions may act as bases, but are not expected to interact with coffee particulates. Thus, water with a high cationic concentration should facilitate a greater extraction of flavorsome notes in coffee. Along with Maxwell and his partner Lesley, we’ve recently published our results.

The world of coffee is an unusual place. As mentioned earlier, Maxwell is the 2014 UK Barista Champion. To be crowned this, you must submit an espresso, a cappuccino and a signature drink to a panel of four judges. You have 15 minutes to do so, and are judged on knowledge of the coffee, your overall presentation and cleanliness, flavour, technical ability and so on. Armed with the knowledge gleaned from our research into the interactions of ions in solutions, I designed different waters for different extractions, to bring out different flavours. This was particularly intriguing for the signature drink which featured an espresso shot mixed with two grape extracts brewed in different water – one with high cation content, one with high base content – to extract different flavours from the grapes. With this victory (for science, I like to think), we are now headed to the world barista championships in Rimini, Italy, June 8–12. I hope that our artillery of scientific knowledge will see Maxwell becoming the 2014 World Barista Champion.

If you find yourself in Bath and fancy a coffee, I would highly recommend you head down to Colonna and Small’s to see and taste the result in person, you’ll be pleasantly surprised. At very least, you can use this story to prove that work really does get done in the coffee shop.

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Categories: Education

May 2014: Engaging and educating with science

Royal Society R.Science - 28 May, 2014 - 15:13

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Share prices around merger deals are not real

Chemistry World blog (RSC) - 20 May, 2014 - 13:17

In the wake of AstraZeneca’s (AZ) stout rebuttal of Pfizer’s overtures to a takeover bid, media all over the place are reporting the ‘disappointing’ news that AZ’s share price has ‘tumbled’. In my opinion this is typical of the short-memory effect that looking at share prices seems to somehow bestow on even some quite sensible people.

Look at the facts and circumstances – AZ has just been subject of speculation over a possible takeover. This inevitably leads to an increase in the share price as speculators look to take advantage of the premium price that any bid is bound to offer, or the rising price in the build-up (partly caused by demand arising from their own speculation).

Once the possibility of that short-term gain is removed – in this case by AZ shutting the door in Pfizer’s face – the price will inevitably go down, as those short-term investors seek to cash in their holdings and go off elsewhere in search of another stock that’s on the rise.

But here’s the important bit. AZ’s share price is still significantly higher than it was in the middle of April, before all this talk started. The only people who have actually lost money are the ones who bought their shares after 25 April, and sold them yesterday or today.

— Pfizer (red) and AZ (blue) over the last month (from Google finance)

It is slightly more revealing to look at Pfizer’s share price over the last couple of months, which overall is significantly down. This wasn’t helped by some decidedly mediocre sales figures in the company’s quarterly announcement at the beginning of May. And the further Pfizer’s price falls, the less valuable that combined cash-and-stock offer becomes.

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Categories: Education

WebElements: the periodic table on the WWW [http://www.webelements.com/]

Copyright 1993-2011 Mark Winter [The University of Sheffield and WebElements Ltd, UK]. All rights reserved.