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Alan Rawle
Alan Rawle is our Applications Manager. Alan has a degree in Industrial Chemistry and a PhD in catalysis, which was where he first encountered the topic of particle size. He developed a career in liquid crystal displays engineering, electro optics and lasers, followed by 3 ½ years in technology transfer based at the Royal Signals and Radar Establishment. He joined Malvern Instruments 1990, and his current role involves assisting customers in their applications, key account support, writing, submitting & presenting peer-reviewed papers and writing application notes. He also has links with international bodies such as NIST, ISO, ASTM.

Claisse, Kinexus, Malvern Panalytical Events, Rheology »

[15 Jun 2017 | ]

To support the growing interest in Malvern PANalytical technologies for use in the food and drink industry, we held a joint free seminar devoted to this extremely important industry sector. This took place on Wednesday, June 8th in the Marriott Hotel Schaumburg, Chicago and saw more than 20 enthusiastic attendees from the food industry attend for an applications-focused set of presentations stressing the importance of Malvern PANalytical’s  complementary analytical techniques and the value they add to this sector.  We kicked off with a ‘Deluxe Continental Breakfast’ as befitting the attendees.

Personally, I must say that this was …

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Laser Diffraction, Mastersizer, Meet the Experts, Particle size, Tech Talk »

[13 Jun 2017 | ]

I recently presented a webinar exploring the practical aspects of sieving method – the advantages and disadvantages.  I compared the method to other techniques such as laser diffraction indicating the increased wealth of information that can be obtained with these more modern instrumental techniques and the common pitfalls and assumptions of the screening technique.
More than 800 of you registered for the webinar and I received a large numbers of interesting questions which I have been working steadily through. I thought it would be a good idea to share the questions and answers via the blog, so here they …

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[29 Dec 2016 | ]

In light scattering theories and approximations, we assume that for large particles the extinction coefficient, Qext, is exactly 2. This is the basis of the Fraunhofer approximation meaning that one unit of light is lost from the shadow of the particle and one unit of light by diffraction. In the far field this presents us with Babinet’s conjecture which we’ll not deal with at this time.
When we come to examine the actual light scattered by particles we find at smaller sizes that this assumption (Qext = 2) is not valid …

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Particle size, Tech Talk »

[15 Dec 2016 | ]

Paul Kippax alerted me to an interesting piece in Chemical Watch (Global Risk and Regulation News). It’s based on a comment by the European Commission Joint Research Council (JRC) that:
‘The term “particle size” does not sufficiently describe the exact quantity that is measured, across different nanomaterial particle size analysis (PSA) methods’.
‘Our findings show that the equivalent diameter values of some measurement methods do not agree and that the results of some others only agree, due to their relatively large uncertainties,” the study authors say.
“For a reliable comparison of particle size, …

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Meet the Experts »

[6 Dec 2016 | ]

To celebrate the knowledge, support and dedication of our employees we are introducing our first live panel discussion to help you solve your current challenges.
We invite you to write in your questions, comments, feedback and wish lists for our panel to answer.
Our seasonally dressed experts will be live on Webcam to help on December, 16th (10:30 EDT time).
Save the date to your calendar!
Whether it’s related to helping you gain the most value out of your current instrument or to discover more about our latest technologies we encourage you to take …

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Meet the Experts »

[21 Jun 2016 | ]

You may have read and have been interested in a recent BBC article dealing with how poll predictions can go badly wrong before an election.  Or you may not:
See: Election polls 2015: What went wrong?  http://www.bbc.co.uk/news/uk-politics-35350274
With the upcoming EU referendum in the UK and the Presidential elections in the US, what are the chances of us predicting the outcomes before the ballot papers are counted?
In a recent New York Times article by Frank Bruni (“Our insane addition to polls” Sunday January 24th, 2016) there’s a quote by Ralph Reed “There seems …

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Malvern Panalytical Events »

[9 Mar 2016 | ]

Don’t forget our remaining short courses
Today
Separations: Fundamentals of Advanced Gel Permeation & Size Exclusion Chromatography Detection – Ulf Nobbmann
Thursday, March 10, 2016
Nanocrystallite and Nanoparticle Size Analysis with an X-Ray Diffractometer – Alan Rawle & Scott Speakman (PANalytical)
Pittcon is a show where there are literally bags full of giveaways on every stand.  Every year we try to come up with something inventive that is both useful and give some publicity to the company.
This year it was interesting to see how our Spectris sister companies, PANalytical and Omega, tackled the same issue that perplexes us on a …

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Malvern Panalytical Events »

[8 Mar 2016 | ]

This year Pittcon moved a little NNE from New Orleans, LA, to Atlanta, GA, home of Coca Cola.  According to Wikipedia, Atlanta is considered an “alpha-” or “world city” ranking 36th among world cities and 8th in the nation with a gross domestic product of $270 billion.  So, probably a good city to return to.  Georgia is famous for peanuts (think Jimmy Carter) and peaches (think Allman Brothers Band – actually formed in Jacksonville, FL, just on the state border south of GA).
This year we were exhibiting on a stand …

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Taylor Dispersion Analysis, Viscosizer TD »

[25 Feb 2016 | ]

I’m reminded of de-sodium-fusion but will avoid this as an opening sentence as it will be understood by but a few chemists……  Ah well, wrong again….
In England, in the early 1800’s, there was a group formed solely for the ‘diffusion of knowledge’.  It was actually more correctly called “The Society for the Diffusion of Useful Knowledge (SDUK) founded in 1826, and wound up in 1848.  The Society published inexpensive texts intended to adapt scientific material for the rapidly expanding reading public. Wikipedia further states “An American group of the same …

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Kinexus, Rheology »

[11 Feb 2016 | ]

Rheological – geological – but not mythological…
Pluto (not the Disney character – that’s another story) is a word that provokes emotion and comment. This ‘Planet X’ discovered in 1930 by a young graduate student Clyde Tombaugh, never fails to excite the science in all of us.
Demoting Pluto as a ‘real’ planet to a ‘dwarf’ planet a few years back attracted controversy with a huge public outcry and input for and against – the case for demotion was made mainly by a small bunch of political astronomers, it has to be said, so you can …

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Particle shape, Particle size »

[25 Nov 2015 | ]

Ever thought about measuring the size of a potato?  We’ll probably be consuming vast quantities of these in various forms (fries, roasted, mashed, even potato salad which signals summer in the US). Well, the humble potato is a good example of the philosophy of the most basic particle size question “What size is my particle?”. Do we buy our potatoes on the basis of number (I can understand this for large baking potatoes or the tiny new potatoes we used to see every year in my youth in England – now of …

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Meet the Experts, Particle size, Rheology, Zeta potential »

[29 Sep 2015 | ]

When you see the words “perfect packing” are you thinking of getting ready for that vacation and neatly folding your swimming costume and other clothes into your suitcase?  Or are you thinking of the worst-suitcase scenario when you’re packing after your vacation and trying to get that didgeridoo, boomerang,  and other assorted odd-sized souvenirs into that same suitcase, finding you have a problem, and having to buy another suitcase or ship the odd-shaped ornaments by other routes?
 
I won’t bore you with the story of trying to be smart, shipping my …

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Particle size »

[21 Jul 2015 | ]

Variety is the spice of life.  And variety is the constant theme of my webinars.  We’ve looked this year at absinthe (which makes the heart grow fonder) louching, the rheology of cheese and mayo (another cheesy subject), coffee (think of your own pun), and now the particle size of spices continuing a sort-of strange food menu.
What’s the difference between an herb and a spice?  Ever wondered and asked this question?  You’ll probably grind your own pepper (or even coffee) at the time just before you consume them as an addition …

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Malvern Panalytical Events, Rheology »

[14 Apr 2015 | ]

Tough cheese! Ponderings on cheese & rheology

My mother used to tell me that if I ate cheese late at night I’d dream.  I always wondered what was wrong with dreaming…..  Cheese is one of the essential food groups along with chocolate – indeed my local Hubbertucky goat cheese producer, Westfield Farm, makes a wonderful chocolate goat cheese combining both essentials….  Cheese is a mandatory comfort food probably because of the potentially high fat content and the extraordinary amount of choice with respect to type and flavor: think of the famous …

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Malvern Panalytical Events, Mastersizer, Nanosight, Particle size, Tech Talk, Zetasizer »

[13 Feb 2015 | ]

This bad pun is the title of my next webinar scheduled for February 18th.  This title has also been used in a short book of poems by Mark Begley (of which I have copy 33/35…).
I guess you couldn’t ask for a better mix of art, science, myth, intrigue and a murder or three – ideal Valentines viewing.  Indeed “it would be difficult to find a liquor with a more sordid past than absinthe.”
A full 2 years before the forerunner of the FDA in the USA banned cocaine and heroin (in …

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Dynamic Light Scattering, Gel permeation chromatography, Laser Diffraction, Malvern Panalytical Events, Meet the Experts, Particle size, Size Exclusion Chromatography, Zeta potential »

[11 Dec 2014 | ]

Having just been down to New Orleans or Nawlins (check out Captain Beefheart and His Magic Band’s pronunciation on the classic track Click Clack – I bought the album long before most of the readers were born!) for an ASTM E56 Nanotechnology meeting, my thoughts naturally turned to my next visit when Pittcon 2015 will be there (March 8 – 12, 2015: Ernest N. Morial Convention Center; New Orleans, LA USA.  See: )
Yawl probably all recall the competition that we ran on our stand – guess the number of candies in the …

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Meet the Experts, Tech Talk »

[5 Dec 2014 | ]

Ever wanted to calculate the yield of an atomic weapon in terms of equivalent tons of TNT?  Would you ever get the opportunity?
Well, Enrico Fermi wanted to do this in 1945 at the first testing of an atomic bomb in the New Mexico desert.  As the shock wave passed he dropped small pieces of paper and the fact that they ended up around 2.5 meters (8 feet) from his body allowed him to estimate the yield as around 10 kilo tons equivalent of TNT – immediately without apparent thought.  A …

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Rheology, Tech Talk »

[8 Aug 2014 | ]

Randy Byrne, Malvern Instruments’ VP for Commercial Development, has formulated this excellent (not a trick-) question: “Which has the higher viscosity at room temperature – mayonnaise or honey? (Randy claims no originality for this question!)  We’ll return to this later……  Now, one factor that seems common to many techniques is the indescribable ‘sample preparation’ which I’ll now attempt to describe….
The specific question is “Does sample preparation affect my sample?’ The obvious and true answer in both cases is “Yes”.  So, clearly we have to reformulate the question – just as the sample preparation reformulates …

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Malvern Panalytical Events »

[6 Mar 2014 | ]

Monday was the first day of the exhibition part of the show at Pittcon and the opening ceremony that took place in McCormick Place was captured in Pittcon Today, the paperwork I talked about in the last blog:

 (Thanks to Pittcon Today for the image – http://viewer.zmags.com/publication/ece7d8b8#/ece7d8b8/1)
Our stand was also paid a visit by the ever-popular Chromeleon so there was an excellent photo-opp:

I was also talking about capturing the Chromeleon but couldn’t persuade others to rugby tackle the green lizard so that we could determine more about its personality (obviously a very friendly amphibian) …

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Malvern Panalytical Events »

[5 Mar 2014 | ]

The one thing about Pittcon is the huge amount of giveaways and technical literature given away by exhibitors.  And the gimmicks to pull people into the stand…..  The Pittcon bag is a given – this year a beer/soda cooler:

The amateurs at Pittcon are easy to spot – they’re carrying huge amounts of information and other items in the numerous canvas promotional bags.  Pens are the norm – Malvern’s “Guess the number of particles in the candy jar” promo has a particularly nice pen – a high powered light one end …

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