Conventional methods use liquid nitrogen to cool the protein crystals (with cryoprotectants) so that low-density amorphous (LDA) ice, rather than crystalline ice, forms. Kim et al. developed a procedure known as high-pressure cryo-cooling that uses high-pressure on protein crystals to form high-density amorphous (HDA) ice instead .
While the foundational physics of scattering is common to all application areas, individual fields have diverged over the years to develop many specialized tools appropriate to the type of matter under investigation. As science advances, however, areas like structural biology, materials science, and engineering have greater overlap. We organized a dual-track workshop this year aimed at getting soft-matter scientists and biologists in one room to promote exchange.
Princeton group tests role of structure on organic electronic thin film properties through reversible control of crystalline phase
In a new article published in Advanced Functional Materials (http://dx.doi.org/10.1002/adfm.201502412), Princeton Ph.D. candidate Geoff Purdum in Lynn Loo’s group in the Chemical and Biological Engineering Department at Princeton and his co-authors shed new light on this issue. In particular, they report reversible access of two polymorphs exhibited by core-chlorinated naphthalene tetracarboxylic diimide (NTCDI-1), an organic semiconductor developed by BASF.
Nine educators and 85 students grades 3-8th from Syracuse, Tully, South Seneca, Interlaken and Ithaca were engaged in science learning through experience and exploration. Awesome!!!
X-ray “Supercrystallography” helps the structural reconstruction of nanocrystal assembly from atomic to mesoscale
Both the instrumental and analytical developments were led by Staff scientist Zhongwu Wang at Cornell High Energy Synchrotron Source (CHESS). This first-of-the-kind X-ray approach together with the growth of single supercrystal and detailed structural analysis and simulation from atomic to mesoscale level was reported in Issue September 09, 2015 at Nano Letters .
Dichtel, an associate professor in the Department of Chemistry and Chemical Biology at Cornell University, has made continuous use of CHESS over the past few years to aid his group’s studies of covalent organic frameworks (COFs). The group regularly relies on the G2 station at CHESS to characterize the crystalline and orientational order of different COFs and under different conditions [1-3], including different substrates such as single-layer graphene. Those results have contributed to the group’s development of COFs for various applications, such as vapor detection .
Josh and his students have already performed first x-ray scattering experiments related to this project at D1 station in the summer run 2015.
The NASA Program aims to support “early stage technologies that will address high-priority needs of America's space program” (see NASA Press Release). Eight projects were selected out of a national competition which will be funded for $200K per year up to three years.
We congratulate Josh and are looking forward to more exciting experiments of his group at CHESS!
The x-ray pulses have many longitudinal modes, so energy fluctuates over a finite bandwidth. Longitudinally coherent x-ray pulses can be made by sending longitudinally coherent radiation along with electrons through the undulator. This so-called “self-seeding” is done between long undulator sections by separating electron from x-ray beams using a magnetic chicane, monochromatizing the x-rays, and finally recombining beams as indicated in Figure 1.