2019 has been declared by UNESCO as the Year of the Periodic Table. To celebrate, we are releasing a series of blogs about our favourite elements and their importance to the chemical industry. Today, on International Women’s Day, we look at the two elements radium and polonium and the part Marie Curie that played in their discovery.
Who is Marie Curie?
Marie Sklodowska and her future husband Pierre Curie.
Marie Sklodowska-Curie was born in 1867 in Poland. As a young woman she had a strong preference for science and mathematics, so in 1891 she moved to Paris, France, and began her studies in physics, chemistry and mathematics at the University of Paris.
After gaining a degree in physics, Curie began working on her second degree whilst working in an industrial laboratory. As her scientific career progressed, she met her future husband, Pierre Curie, whilst looking for larger laboratory space. The two bonded over their love of science, and went on to marry, have two children and discover two elements together.
After finishing her thesis on ‘Studies in radioactivity’, Curie became the first woman to win a Nobel Prize, the first and only woman to win twice, and the only person to win in two different sciences.
Curie, along with husband Pierre and collaborator Henri Becquerel, won the 1903 Nobel prize in Physics for their radioactivity studies, and the 1911 Nobel prize in Chemistry for the isolation and study of elements radium and polonium.
Curie won the Nobel prize twice in two different subjects. Image: Pixabay
As of 2018, Curie is one of only three women to have won the Nobel Prize in Physics and one of the five women to be awarded the Nobel Prize in Chemistry.
Polonium, like radium, is a rare and highly reactive metal with 33 isotopes, all of which are unstable. Polonium was named after Marie Curie’s home country of Poland and was discovered by Marie and Pierre Curie from uranium ore in 1898.
Polonium is not only radioactive but is highly toxic. It was the first element discovered by the Curies when they were investigating radioactivity. There are very few applications of polonium due to its toxicity, other than for educational or experimental purposes.
Radium is an alkaline earth metal which was discovered in the form of radium chloride by Marie and her husband Pierre in December 1898. They also extracted it from uranite (uranium ore), as they did with polonium. Later, in 1911, Marie Curie and André-Louis Debierne isolated the metal radium by electrolysing radium chloride.
The discovery of radium led to the development of modern cancer treatments, like radiotherapy.
Pure radium is a silvery-white metal, which has 33 known isotopes. All isotopes of radium are radioactive – some more than others. The common historical unit for radioactivity, the curie, is based on the radioactivity of Radium-226.
Famously, radium was historically used as self-luminescent paint on clock hands. Unfortunately, many of the workers that were responsible for handling the radium became ill – radium is treated by the body as calcium, where it is deposited in bones and causes damage because of its radioactivity. Safety laws were later introduced, followed by discontinuation of the use of radium paint in the 1960s.
Marie Curie: A life of sacrifice and achievement. Source: Biographics
Curie’s work was exceptional not only in its contributions to science, but in how women in science were perceived. She was an incredibly intelligent and hard-working woman who should be celebrated to this day.
English wine is on the rise. In 50 years, production has increased by more than three orders of magnitude, from a negligible 1,500 bottles/year to a respectable 5.3 million.
Meanwhile, on the other side of the English Channel, grapes are harvested around two weeks before the traditional dates. In the Champagne region, harvest kicked off on 26 August 2017, while the average date for previous years was 10 September. In Burgoyne, home of Beaujolais wines, harvest began on 23 August, also two weeks ahead of schedule. Harvest workers in that area are also doing night shifts to reduce heat stress for the sensitive grapes.
French vineyards are struggling with the changes to traditional harvests. Image: Max Pixel
Both phenomena – the success of English wine and the earlier harvests in France – are linked to climate change. In a few decades, the favourable wine-growing conditions historically enjoyed by the Champagne region may have migrated to England.
As the life cycle of the grapevine – and therefore quality and quantity of the wine obtained – is extremely sensitive to temperature and weather extremes, wine growers have already been noticing the effects of climate change for years. Researchers have detailed how conditions have changed, how they are likely to change further, and what vineyards can do to adapt.
All agricultural products are likely to be affected by climate change at some point, but wine occupies a special position due to its high value. Therefore, wine growers have always watched the weather and its effects on their vineyards very closely, and recorded their observations.
Climate scientist Benjamin Cook from Columbia University at New York and ecologist Elizabeth Wolkovich from Harvard University, have analysed harvest data spanning more than 400 years, from 1600 to 2007, from European regions, together with the weather data.
While many studies have covered the last few decades, this one reaches back to the time before the Industrial Revolution.
Higher temperatures in spring and summer generally speed the whole process and lead to earlier harvests, like the one in 2017, while cool and rainy summers can delay the phrenology and thus the harvest time. Traditionally, the observation was that a warm summer and a period of drought just before grape picking is the best recipe for an early harvest.
Grape picking is easiest after a warm summer. Image: Pixabay
‘Our research, and other work, has clearly and unequivocally demonstrated that climate change is already affecting viticulture worldwide,’ explains Cook, adding that: ‘There are lots of opportunities for adaptation in various locations, such as planting different varieties, but the most important thing is for people to starting planning for the next several decades, when conditions are likely to get even warmer still.’
Adapt or move?
So, what could be changed? Short of pulling up Pinot Noir vines in Champagne and replanting them in Dorset, there are some steps wine-makers can take to ensure a good harvest.
The Chemistry of Wine. Video: Reactions
For instance, growers could add a few days to the ripening cycle by delaying the spring pruning, or by allowing the vines to grow higher above the ground, where the air is slightly cooler than just above the soil. While these changes are benign, other measures, such as reducing the leaf area, may have complex consequences that could interfere with the quality of the wine.
In selecting the plant material, growers could reverse the trends of the 20th Century, when it made sense to select rapidly ripening varieties. Simply by adapting the choice of variety from among the range of varieties already used in a given region to the changing climate, growers can to some extent mitigate the anticipated effects.
Alternatively, wine production could migrate closer to the poles. Wines now coming from California may be produced in Washington State, and the premium fizz we now call Champagne may one day be known as Devon or Kent.