In Situ Transmission Electron Microscopy Study On The Phase Transitionsin Lead-Free (1−X)(Bi1/2na1/2)Tio3–Xbatio3 Ceramics, C. Ma, Xiaoli Tan
Materials Science and Engineering Publications
The phase transitions in unpoled lead-free (1−x)(Bi1/2Na1/2)TiO3–xBaTiO3 (x = 0.06 and 0.11) ceramics are investigated using hot-stage transmission electron microscopy (TEM). It is found that large ferroelectric domains in both ceramics start to disappear around Td, the depolarization temperature. After the transition, both compositions exhibit the P4bm tetragonal symmetry in the form of nanodomains. The structural transition observed by the in situTEM experiments seems to be gradual and occurs within a temperature range of several tens of degrees, in contrast to the sharp ...
Patterning Of Alloy Precipitation Through External Pressure, 2010 University of Pennsylvania
Patterning Of Alloy Precipitation Through External Pressure, Jack A. Franklin
Publicly Accessible Penn Dissertations
Due to the nature of their microstructure, alloyed components have the benefit of meeting specific design goals across a wide range of electrical, thermal, and mechanical properties. In general by selecting the correct alloy system and applying a proper heat treatment it is possible to create a metallic sample whose properties achieve a unique set of design requirements. This dissertation presents an innovative processing technique intended to control both the location of formation and the growth rates of precipitates within metallic alloys in order to create multiple patterned areas of unique microstructure within a single sample. Specific experimental results for ...
Atomic Force Microscopy For Better Probing Surface Properties At Nanoscale: Calibration, Design And Application, 2010 The University of Western Ontario
Atomic Force Microscopy For Better Probing Surface Properties At Nanoscale: Calibration, Design And Application, Yu Liu
Electronic Thesis and Dissertation Repository
To measure force by AFM with high resolution requires accurate calibration of optic – lever detection sensitivity and spring constant. On biological AFM force mode, the coupling effects of the liquid environment, spot size of laser beam and laser spot location on AFM cantilever backside, must be considered to correlate the static sensitivities from force curves in air and in liquid for calibration. An effective model has been developed first and experimentally elucidated to calibrate the static sensitivity in liquid. The proposed model eliminates inconvenience of static sensitivity calibration in liquid with possible contamination sources.
The static sensitivity based on force ...
Self-Assembly Of Colloidal Particles From Evaporating Droplets: Role Of Dlvo Interactions And Proposition Of A Phase Diagram, Rajneesh Bhardwaj, Xiaohua Fang, Ponisseril Somasundaran, Daniel Attinger
The shape of deposits obtained from drying drops containing colloidal particles matters for technologies such as inkjet printing, microelectronics, and bioassay manufacturing. In this work, the formation of deposits during the drying of nanoliter drops containing colloidal particles is investigated experimentally with microscopy and profilometry, and theoretically with an in-house finite-element code. The system studied involves aqueous drops containing titania nanoparticles evaporating on a glass substrate. Deposit shapes from spotted drops at different pH values are measured using a laser profilometer. Our results show that the pH of the solution influences the dried deposit pattern, which can be ring-like or ...