David Turnbull died peacefully at home last Saturday, April 28th, at age 92.
He was for many years Gordon McKay Professor of Applied Physics at Harvard University. His seminal work included theoretical and experimental studies of nucleation of crystals, the glass transition and the amorphous state, crystal growth, and atomic diffusion.
Welcome to the May 2007 issue. This issue focuses on experimental nanomechanics of nanobuilding blocks. The extremely small dimensions of nanobuilding blocks (for instance, nanoparticles, nanotubes, and nanowires) have imposed great challenges to many existing instruments, methodologies, and even theories. In this issue, we will discuss – (1) experimental techniques and (2) size-effects.
Huang et al., PRL 98, 185501 (2007)
Watch movies at: http://netserver.aip.org/cgi-bin/epaps?ID=E-PRLTAO-98-002719
We report exceptional ductile behavior in individual double-walled and triple-walled carbon nanotubes at temperatures above 2000 C, with tensile elongation of 190% and diameter reduction of 90%, during in situ tensile-loading experiments conducted inside a high-resolution transmission electron microscope. Concurrent atomic-scale microstructure observations reveal that the superelongation is attributed to a high temperature creep deformation mechanism mediated by atom or vacancy diffusion, dislocation climb, and kink motion at high temperatures. The superelongation in double-walled and triple-walled carbon nanotubes, the creep deformation mechanism, and dislocation climb in carbon nanotubes are reported here for the first time.
With a shallow chemical etching the roughness with spatial frequency below a critical value grows while the roughness of higher frequency decays.
Subject: NSF Proposal Writing Workshop ( August 22-23, 2007 - Alaska)
Sponsored by NSF, a Proposal Writing Workshop will be held on August 22-23, 2007, at University of Alaska-Fairbanks. The workshop mainly aims to provide future proposal submitters (in all disciplines funded by NSF) with knowledge and tools to write good proposals, proposal review experience, and it will enable interactions with NSF program directors and recent NSF awardees. The event is targeted at an EPSCoR state, Alaska. However, the workshop is open to participants from other states as space permits.
Yesterday I had the distinct pleasure of seeing a mechanics seminar delivered "tag-team" by Ken Johnson and Jim Greenwood. (I know several people have thought I was a bit mad for jumping "across the pond" but there are really some amazing benefits of being part of the Cambridge Engineering faculty!)
Introduction
The blogosphere is abuzz with the latest report of the generalisation of the von Neumann-Mullins grain growth relation to 3 (and N) dimensions by MacPherson and Srolovitz (As an interesting aside, almost all the reports say mathematical structure of beer foam structure resolved, or words to that effect --hence, I also decided to join the bandwagon on that one). I heard Prof. Srolovitz describe the work in a seminar nearly six months ago. Based on my notes of the talk, I would like the explain their work in this post. Curvature in the following refers to mean curvature (and not Gaussian).
We have recently reported the piezoelectric thick film microcantilever, which enables the in-situ real-time detection of the protein related to disease (e.g. C reactive protein) in liquid environment. This work was published at APL (click here).
"In-situ real-time monitoring of biomolecular interactions based on resonating microcantilevers immersed in a viscous fluid"
JOM is a monthly publication of TMS--The minerals, metals, and materials society. It covers a wide range of materials topics. I expecially like the overview articles, which, in four or five pages pack lots of information. Further, the historical articles about metallurgy and materials in ancient civilizations will interest those of you who like to read about history in general, and science history, in particular.
