Want to learn more about one of science's heroes from history, Henry Moseley? Moseley solved one of chemistry's greatest puzzles - determining what distinguishes elements from one another and developed a means of identifying elements based on their atomic characteristics. Sadly he lost his life fighting at Gallipoli in WWI.
Learn more about his life and legacy by watching our online film here.
In the periodic table, the post-transition metals sit between the transition metals on their left, and the metalloids on their right. These metallic elements include aluminium, gallium, indium, tin, thallium, lead, and bismuth. Most are soft or brittle, with poor mechanical strength, and have melting points lower than the transition metals.
Lead is one of the seven metals of antiquity that humans identified and made use of in prehistoric times (the other six are gold, silver, copper, tin, iron, and mercury). Lead is now used in alloys, solder, and roofing. Gallium and indium are semiconductors, and thallium is highly toxic and has been used as a pesticide.
Iron makes up a bit more than a third of Earth’s mass, but a lot is locked away in the core of the planet. Even so, it plays an incredibly important role in our lives. In humans and vertebrate animals, iron (in the form of hemoglobin) carries essential oxygen through the body in the bloodstream. It is also a critical element in the metabolism of hundreds of proteins and enzymes involved in body functions, such as DNA synthesis and cell growth.
Iron is a transition metal, and a workhorse element for industry. Although, historically, we’ve moved on from the Iron Age, in fact we rely on iron to make all kinds of things. It has an ability to form an astonishing range of alloys, and their properties can be finely tuned for properties such as super-hardness, extreme tensile strength, or even vibration damping. Roughly 90% of all metal refined is iron, and that’s because it’s cheap and easily welded, machined, tempered and generally moulded into whatever we need it to be. Its only flaw is that it oxidises to form rust - an intensely destructive chemical reaction that costs untold billions each year.
It’s of no surprise, then, that iron features quite often in the ground-breaking experiments scientists carry out at Diamond. They cover the whole range of sciences, from biology and medicine, through environmental sciences and engineering to fundamental physics and even heritage science. Here are a few recent examples:
Scientists from the University of Oxford and the University of Wisconsin-Madison teamed up with Diamond to see whether they could induce tiny magnetic vortices to form in a form of iron called haematite (rust, essentially). Vortices are fascinating, dynamic structures that naturally occur in sizes ranging from the immense (think tornado) to the microscopic. In some cases, their formation is thwarted by long-range forces, and the long-range forces in ferromagnetic materials (like the magnets on your fridge) make it difficult for tiny magnetic vortices to form. But haematite is an antiferromagnet, in which long-range forces don’t occur. So the scientists went looking for magnetic vortices in haematite, and not only found them, but were able then to transfer them from the haematite into a ferromagnetic material. Ultimately, this could lead to a new generation of electronic devices that move beyond the silicon we currently rely on. Read more here.
The coastal regions downstream from glaciers are highly productive ecosystems, one example of which is the large summer phytoplankton bloom in the Labrador Sea. One possible explanation for this high productivity is that meltwater from glaciers is supplying iron to these areas. Iron is an essential micronutrient for marine phytoplankton, and in large areas of the world’s oceans its availability is a limiting factor for growth for these primary producers, on which the marine food web depends. Iron supply is also a critical factor in dictating the strength of the ocean ‘biological pump’, which affects concentrations of carbon dioxide in the atmosphere, and hence the global climate. Glaciers and ice sheets are a significant source of nanoparticulate iron, but how important it is to the marine environment is still a bit of a mystery. A team of researchers from the UK and Germany used high-resolution imaging and spectroscopy at Diamond to investigate the amount and type of iron present in glacial sediments, and found they could be very important indeed. Read more here.
Humans have been using iron to make weapons, tools and ceremonial items for more than 20,000 years, but once these objects have been excavated they are at risk from corrosion, which can be accelerated in the presence of chlorine. Each recovered artefact has to be conserved to prevent it from deteriorating in the presence of air and water. Until now, a comparison of the effectiveness of different conservation methods has been hampered by the variable nature of both the artefacts found, and the environment in which they were buried.
Alzheimer’s disease is a neurodegenerative disease that is associated with dementia and shortened life expectancy. The disease is characterised by the formation of protein plaques and tangles in the brain that cause damage, and there’s a link to elevated iron levels in certain regions of the brain.
Volcanic eruptions can be triggered (or ended) by changes in the magma (molten rock) in or beneath the planet’s crust. The cause of these changes is often thought to be a result of the mixing of different batches of magma in the ‘plumbing system’ below the volcanoes. Volcanologists are working on detecting and understanding these changes, by examining volcanic rock samples, with the aim of being able to accurately forecast future eruptions.
The spinach-guzzling superhero Popeye helped to increase American spinach consumption of the vegetable by a third, but it was all based on a typo. In 1870 German chemist Erich von Wolf correctly measured the amount of iron in spinach, but when he wrote up his notes he put the decimal point in the wrong place, and recorded that spinach contained 35 milligrams of iron per 100 grams, rather than 3.5.
At 35 milligrams per 100 grams, eating spinach would be more like eating a paperclip than a salad leaf!
It wasn’t until 1937 that the error was corrected.