Year of Air: 2013

2 Replies

I mentioned some time ago (Noise Transfer on 3rd April, 2013) that we are privileged to have magnificent views of the river and hills beyond from our city centre house.  From the back bedroom window you can just about see the sea and we are certainly aware of it in most days due to the almost constant sea breeze (or gale).  So despite living in a city centre we are not amongst the 95 percent of EU city dwellers who are exposed to fine particles levels that exceed WHO guidelines.  However, the EU levels are well below those in Beijing that are 300 times the guidelines and probably comparable to those in London during the Great Smog of 1952 that caused cows to choke to death and contributed to the death of about 3000 people.  London has come a long way in the intervening 60 years with current levels of fine particles at about half the WHO guideline, which is 25 micrograms per cubic metre, whereas Beijing has recorded levels of 400. it has been estimated that 13,000 people die prematurely in the UK due to combustion related pollution compared to 1.2 million in China

In my post entitled ‘Extraordinary Technical Intelligence’ on 10th April, 2013 I wrote about the process of urbanisation and industrialisation that has been seen repeatedly across the world.  The progress of this process in a region can also be measured in the levels and type of pollution being generated.  The West has been where China is now, and where India and Africa are likely to go next.  Air pollution on this scale effects the neighbours of the polluter so we have an incentive to help alleviate the problem.  We should also feel a moral obligation because much of the pollution is associated with factories producing goods that we buy and probably don’t repair or recycle at the end their useful life [see ‘Old is Beautiful’ posted on May 1st, 2013] .  If we drew the system boundaries more appropriately then the pollution generated during the manufacture of these goods is as much our responsibility as the manufacturer’s [see my post on 19th December, 2012 about ‘Drawing Boundaries’].

This is the Year of Air, maybe it should have been called the Year of Clean Air to make it absolutely clear what it is all about, i.e. giving everyone on the planet the chance to live and breathe clean air!

BTW, a fine particle is one of diameter less than 2.5 microns or 1/30th diameter of one of your hairs.  One my PhD students is working on tracking nano-particles about a hundred times smaller as they interact with biological structures such as human cells, but that’s another story [see last week’s post].

Sources:

‘Under a Cloud’ by Pilita Clark in the Financial Times, July 13/14, 2013 [ http://www.ft.com/cms/s/0/83ef4b78-eae5-11e2-9fcc-00144feabdc0.html#axzz2cgRhFXMs ].

Yim SHL and Barrett SRH. Public Health Impacts of Combustion Emissions in the United Kingdom. Environmental Science and Technology, 2012, 46 (8), pp 4291–4296.

‘Air Pollution Linked to 1.2 Million Premature Deaths in China’ by Edward Wong in the New York Times on April 1, 2013 http://www.nytimes.com/2013/04/02/world/asia/air-pollution-linked-to-1-2-million-deaths-in-china.html?_r=0

Silva, R.A., et al., 2013, Global premature mortality due to anthropogenic outdoor air pollution and the contribution of past climate change, Environmental Research Letters, 8:034005. http://iopscience.iop.org/1748-9326/8/3/034005/pdf/1748-9326_8_3_034005.pdf

Toxic nanoparticles?

3 Replies

My obsession with kinematics and kinetics over the past few posts is connected to my recent trip to Italy [see my post last week] as part of a research project on the mechanics of nanoparticles.  We are interested in the toxicological effect of nanoparticles on biological cells.  Nanoparticles are finding lots of applications but we don’t completely understand their interaction with cells and organs in the body.  We are interested in particles with diameters around 10 nanometres.  The diameter of a human hair is 10,000 times bigger.  The small size of these particles has potential implications for their kinematics and kinetics as they move through the body.  We know that protein molecules can attach themselves to nanoparticles forming a corona and as part of our research we are looking at how that influences the motion of the particle.  For instance, it might be appropriate to use kinematics for a spherical metallic nanoparticle but kinetics for one with a corona.

Some of you might be thinking, why go to Italy?  Well, other than for the coffee, I have been working with a colleague there for some time on methods of tracking nanoparticles that are below the resolution of optical microscopes.  We have named the technique ‘nanoscopy’ and it allows us to look at live cells and nanoparticles simultaneously without damaging the cell.  So our current research is an extension of the earlier work (see the two papers referenced below).  Of course the more basic answer is that we get on and are very productive together.

BTW – we can’t ‘see’ our nanoparticles because visible light has wavelengths about fifty times larger than the particles, so light waves pass single particles without being reflected into our eyes or camera.  However, a particle does disturb the light wave and produce a weak optical signature, which we utilise in nanoscopy.

Research papers available on-line at:

http://onlinelibrary.wiley.com/doi/10.1002/smll.200800703/abstract

http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2818.2011.03491.x/abstract

No coffee till Christmas

Leave a reply

coffeeNot a decision to give up caffeine until the festive season but a remark by my Italian research student as he finished his cup of coffee on the flight back to England.  He doesn’t consider what we serve in the UK to be coffee and he won’t be back in Italy until the Christmas vacation.  We were in Italy visiting the laboratory with which we are collaborating on his research project.  He is right, the coffee gets much better as you move south and east from the US and UK.

Next time you are enjoying a cup of coffee watch the swirls created as you or a friend stirs in some cream.  You can see streak lines that show the path of the cream in the coffee and reveal the fluid flow in your cup.  It is even better if you have a clear glass.  You can use this as an Everyday Engineering Example to capture students’ attention and to illustrate the kinematics of fluids as in the 5E lesson plan below.

5EplanNoF3_kinematics_of_fluid_motion

Sweeping Kinetics

Leave a reply

Last week I left the rubbish on the streets and encouraged you to make a mess in the classroom.  Partly because kinematics does not help us to analyse the forces involved in sweeping rubbish or, more glamorously, an ice hockey puck.  This is the realm of kinetics in which we need to consider the forces acting on objects to cause or impede their motion, such as the push from a broom and the friction against the pavement.  See the 5E lesson plan attached for more details on how Newton’s laws of motion can be applied in these situations.

You might be thinking ‘why should engineers be interested in forces involved in sweeping rubbish?’  Well, it might not be as glamorous as designing sports equipment but someone has to design street sweeping machines that keep our towns and cities clean and it is arguably more beneficial to society and the environment.  Of course, it would be better for the environment if we didn’t drop rubbish that needed sweeping but that’s another post…

5EplanNoD2_force&acceleration

For more on 5E lesson plans see: my post entitled ‘Disease of the modern age’ on June 26th, 2013 and ‘Sizzling Sausages’ on July 3rd, 2013.

For a set of videos on kinetics try: http://www.khanacademy.org/science/physics/forces-newtons-laws