Search our site

Custom Search

Monday, 23 February 2015

Are Nanomaterials Toxic?

There's a lot of concern about the potential toxicity of nanomaterials, intensified by the absence of regulatory standards. This means they aren’t currently required to be safety tested before being used in commercial products. So are nanomaterials toxic, what limits our understanding and how big are the risks to our health?

What are nanomaterials?

Nanomaterials are defined purely in terms of size - they are between 1 and 100 nm in at least one dimension. 1 nm is one millionth of a mm in length, and may be occupied by as few as three atoms, depending on their kind. Nanomaterials can be sheets, wires, rods, particles or platelets, and can be made of any material and have any other properties. Natural nanomaterials include spiders' silk and cotton, and manufactured nanomaterials include carbon nanotubes, metal and metal oxide particles and soots. They occur in paints, fabrics and cosmetics, food packaging and drug delivery medicines. More than a dozen new consumer products containing nanomaterials enter the market every month[1].

Sunday, 15 February 2015

TWDK Receives All Star Award For User Engagement

Constant Contact logo
TWDK Receives 2014 Constant Contact All Star Award
Recognized for achievements using online marketing tools to drive success

[London, UK][12 Feb 2015] — Science education and communications organisation Things We Don't Know C.I.C. has been named a 2014 All Star Award winner by Constant Contact®, Inc., the trusted marketing advisor to more than 600,000 small organizations worldwide. The award, given annually to the top 10% of Constant Contact’s international customer base, recognizes these select businesses and nonprofits for their significant achievements leveraging online marketing tools to engage their customer base and drive success for their organization. TWDK is one such exemplary organization.

Since 2012, TWDK has helped scientists from across the UK, USA, Europe and Australia to explain the problems they're working on in simple, understandable language. By explaining the things we don't know or understand, how we know there's a problem with our current knowledge and why we haven't been able to answer it already, TWDK aims to improve the public understanding of and engagement with science.

We’re delighted to be recognized by Constant Contact for the way in which we engage with our users, said Ed Trollope, TWDK's founder and CEO. We strive to offer the maximum flexibility for users who wish to be notified of our latest updates - we don't want to send you emails you'd rather not get, and Constant Contact provides an easy way for our users to decide which notifications they wish to receive.

Friday, 6 February 2015

How big are atoms?

You may have heard someone mention the size of atoms, in the media or at school perhaps, and you’ll certainly have heard people talk about how small atoms are. So you may be surprised to hear that we don’t know how big atoms are - not exactly, only approximately. But why not?

There are two main problems with measuring the size of atoms - other than the fact that they’re definitely too small to measure by eye, even through a microscope:
  • Atoms don’t have defined edges
  • Atoms can change their size and shape

Atoms don’t have defined edges

We normally talk about electrons in “atomic shells”, which gives the impression of hard, discrete surfaces, like the kernel of a nut. Sometimes, instead, we say electrons travel in “orbitals”. But this conjures up an image of planetary orbitals - specific lines that electrons are restricted to, like a running track. This isn’t a good model. A better description of electrons around a nucleus is “electron clouds”. These clouds describe fuzzy areas of electron density with difficult-to-determine edges. Electron density is the same as negative charge if you assume an electron is a goo smeared out like a cloud, rather than a particle which inhabits a distinct space. This is exactly what an atom is like. We have a fancy name for it: electron density probability distributions.