Millions of tons of lignin—a biopolymer that strengthens the cell walls of plants—are produced each year by the pulp and paper industry. Although lignin production is widescale, lignin is considered a waste product with no commercial application due to its complexity as a non-uniform material. Incorporation of lignin into commercially important polymers remains a challenge in both pure research and applied industrial environments; yet if we could understand and use this material in a predictable manner, it would have a myriad of applications. Fortunately, a 2018 study in ACS Sustainable Chemistry & Engineering has revealed how to prepare and characterize different copolymers of lignin and polylactide (PLA).
At the University of British Columbia, Professor Jaymie Matthews of the Physics and Astronomy department is seeking to improve exoplanet detection by increasing the accuracy of gravitational field measurements. In a paper published by Matthews in 2016, a new way to measure the surface gravity of stars with accuracies of 4% is presented. Matthews said: “If you don’t know the star, you don’t know the planet.” Another group of Scientist at the University of Washington as of 2014 measured the diameter of a “super-earth” with an accuracy of 1%, or about 148 miles at 300 light years away.
While stars like Pegasi 51 and it’s exoplanet might be 50.45±0.10 light years away and far from reachable, the star and planet are an endless source of curiosity for astronomers. With exoplanet detection growing as a field, the discovery of more nearby Earth-like planets might be worth watching out for.
The ability for scientist to develop new drugs for everything from rare diseases to headaches is often reliant on precedent and systematic investigations. These methods are often costly and time consuming. Similar problems arise in development of new materials that may enhance our energy production. Our limited ability to rationally design materials hampers their development. This leads to reliance on our ability to recognize the trends and behavior of already existing materials. However, what if we could amplify the ability to recognize patterns beyond human limits? Machine learning answers this problem.
A graph depicting the general algorithm machine learning follows. Source: Wikimedia Commons
While machine learning is a form artificial intelligence, our jobs are safe. Machine learning is the use of statistics and the power of computers to predict results or identify trends in data. The general method relies on the input of “training” data which is analyzed using statistics. After developing a model, information may be inferred from new data the computer encounters.
Large technology companies have recognized the advantage of integrating machine learning into technology development. Google is one example that has successfully introduced it. Gmail uses machine learning to service 1.5 billion active accounts. They claim to detect 99.9% of phishing and spam mail from entering the user’s inbox. However, machine learning is not limited to technology companies. Chemistry researchers have quickly adopted it.
Total Number of Chemistry Publications with “Machine Learning” in Title
Starting in 1969, the first chemistry journal article with “machine learning” in the title was published. By combining machine learning with a common technique called mass spectrometry, Peter Jurs at the University of Washington was able to determine chemical composition of “unknown” chemicals using the input of 348 unique patterns as “training” data.
More recently there has been an almost exponential increase in the number of chemistry publications applying machine learning. In the last two years approximately 6 times as many publications were made than in the past 48 years. Tommi Jaakkola, a Professor of Electrical Engineering and Computer Science at MIT said at a consortium about implementing machine learning in the pharmaceutical industry: “by marrying chemical insights with modern machine learning concepts and methods, we are opening new avenues for designing, understanding, optimizing, and synthesizing drugs.” The materials science community has also seen integration with the development of novel long chained molecules called polymers for photovoltaics by scientist at Osaka University. Shinji Nagasawa, the lead author explained the importance: “there’s no easy way to design polymers with improved properties. Traditional chemical knowledge isn’t enough. Instead, we used artificial intelligence to guide the design process.”
Solar cell efficiency over years showing a substantial increase. Source: Wikimedia Commons
While machine learning is not the solution to all chemical problems or spam mail, it is being widely accepted by the scientific community and technology industry for good reasons. Even with limitations, it’s effectiveness across a wide array of industry and research emphasizes the role it may play in the future of research and development.
—Jonah
References
Graph-powerd Machine Learning at Google. Google AI Blog. https://ai.googleblog.com/2016/10/graph-powered-machine-learning-at-google.html (Accessed Feb 28, 2019).
Jurs, P.C.; Kowalski, B.R.; Isenhour, T.L. Computerized Learning Machines Applied to Chemical Problems: Molecular Formula Determination From Low Resolution Mass Spectrometry. Chem. 1967, 41, 21-27.
Machine Learning, Materials Science and the New Imperial MOOC. Imperial College London. https://www.imperial.ac.uk/news/187054/machine-learning-materials-science-imperial-mooc/ (Accessed Feb 28, 2019).
More than 100 years ago a Dutch scientist named Heike Kamerlingh Onnes at Leiden University discovered a phenomenon in mercury know as superconductivity. When cooled to -269°C the mercury exhibited zero electrical resistance unlike conventional materials that release heat when transporting electricity.
Why is this important if it requires such a cold temperature? Over the past 100 years scientist and engineers have incorporated this phenomenon into our daily lives. This allowed for dramatic advancements in medicine such as the development of the MRI. Our power grid also takes advantage of this weird property. However, only select materials exhibit superconductivity when cooled below a temperature referred to as the critical temperature.
An example of a superconducting radio frequency cavity on display at Fermilab made of Niobium, a common metal in superconductivity applications. Source: Wikimedia Commons
In 1987 the technology was revolutionized when a material called yttrium barium cuprate was found to exhibit superconductivity below -181°C. This temperature is easily reached with liquid nitrogen, a widely accessible coolant. This marvelous material has found itself applied at the Large Hadron Collider in Geneva and most hospitals. While materials with higher critical temperatures have been slowly discovered, recent advancements have been shattering the records.
Timeline of Superconductive Materials Source: Wikimedia Commons
Among these superconductors are a class which only exist at extremely high pressures. The smelly gas that comes from volcanos and is reminiscent of rotten eggs, Hydrogen sulfide (H2S), is one of these. When cooled to -70°C at 1.5 million atmospheres, hydrogen sulfide exhibits an exotic form of high pressure superconductivity. This discovery in 2015 by Mikhail Eremets and Alexander Drozdov at the Max Plank Institute for Chemistry in Mainz, Germany toppled previous records by 39°C, a significant breakthrough in the search for room temperature superconducting materials. Mikhail Eremets said: “Our research into hydrogen sulfide has however shown that many hydrogen-rich materials can have a high transition temperature.”
This has held true with a recently published paper by the same team in December of 2018. Lanthanum superhydride (LaH10) was found to be superconducting at -23°C, however it was at similar pressures to the previous discovery. This value was found to be even higher at -13°C when pressurized up to 2 million atmospheres as published by scientist at George Washington University in January of 2018. Maddury Somayazuli, an associate professor at The George Washington School of Engineering and Applied Science said: “Room temperature superconductivity has been the proverbial ‘holy grail’ waiting to be found, and achieving it-albeit at 2 million atmospheres-is a paradigm-changing moment in the history of science.” Future experiments are expected to provide more breakthroughs in the field.
An engineer at the Advanced Photon Source, part of Argonne National Laboratory where GW University experiments were preformed. Source: Advanced Photon Source Flicker (CC BY-NC-SA 2.0)
While high pressure superconductors lack application, understanding this property may allow for the development of new materials. With continued research and the recent breakthroughs, the phenomenon of superconductivity may further be propelled into future technology that will have a significant impact on our quality of life.
-Jonah
References:
1.Drozdov et al, “Superconductivity at 250K in Lanthanum Hydride Under High Pressure,” arXiv:1812.0156 [cond-mat], Dec. 2018. 2.Somayazuli et al. (2019). Evidence for Superconductivity above 260K in Lanthanum Superhydride at Megabar Pressures. Physics Review Letters, (122), 027001-6. 3.Researchers Discover New Evidence of Superconductivity at Near Room Temperature. (2019, January 15). Phys.org. Retrieved from https://phys.org/news/2019-01-evidence-superconductivity-room-temperature.html 4.Superconductivity: No Resistance at Record Temperatures. (2015, August 18). Max-Planck-Gesellschaft. Retriever from https://www.mpg.de/9366213/superconductivity-hydrogen-sulfide 5.Eck, J. (2018). The History of Superconductors. Retrieved from http://www.superconductors.org/History.htm
