The science community mourns Mildred Dresselhaus, scientists unveil the first magnetic resonance microscope, new details in graphite to diamond pathways, seven Earth-sized planets detected, and more.
This week in science is a review of the most interesting scientific news of the week.
Science community in mourning.
Mildred Dresselhaus, MIT Institute professor emerita of physics and of electrical engineering and computer science, died Monday at the age of 86. Professor Dresselhaus was one of the first scientists to consider the possibility of carbon nanotubes manufacturing and was among the pioneers of nanoscience. Furthermore, she was responsible for launching a new field of energy research by exploring the thermoelectric effect at the nanoscale.
Dresselhaus was the first woman to attain the rank of full, tenured professor at MIT, where she kept working for 50 years even after retiring. Also, she was the first woman to receive the National Medal of Science in Engineering. Finally, in 2014, she was awarded the Presidential Medal of Freedom from President Obama.
Source: MIT Technology Review
Scientists have been searching for years for the reason why graphite turns into hexagonal diamond instead of the more common cubic diamond when exposed to high pressures, what contradicts the theory. But this search now seems to be over, according to a publication by a team of researchers from Fudan University and Shanghai University in China.
Both the cubic and the hexagonal types of diamond and the graphite are carbon allotropes, which means they are made of carbon atoms, but differ on the spatial arrangement. This difference has several consequences to the resulting materials and are responsible for the softness of the graphite, which makes it possible to be used in pencils, but also responsible for the hardness of both kinds of diamond.
The team of researchers has studied all the possible pathways in the graphite-to-diamond transition by using a new type of simulation, called stochastic surface walking. This new simulation allows the identification of the pathways which have the lowest-energy intermediate structures.
