Bottom-up/top-down synthesis of stable zirconium hydroxide nanophases

Bottom-up/top-down synthesis of stable zirconium hydroxide nanophases†

It is well known that the structure of ZrO2 powder synthesized by low temperature calcination of hydrous zirconia is strongly affected by the nature and properties of precursors. In the present paper, we combined a precipitation/restructuring approach (bottom-up/top-down methodology) to produce zirconium hydroxide nanoparticles that transform into stable nanophasic tetragonal zirconia by low te...

Top-down and bottom-up approaches to stable clock synthesis

In this work we present and study bottom-up, or multiplicative, clock synthesis and compare it to a proposed and alternative top-down, or divisive, methodology. The focus of the work is on the short-term stability for each approach and the implications associated with frequency multiplication and division. The analysis and simulation demonstrate that for a common application, a top-down clock s...

Inhibition of Ice Growth and Recrystallization by Zirconium Acetate and Zirconium Acetate Hydroxide

The control over ice crystal growth, melting, and shaping is important in a variety of fields, including cell and food preservation and ice templating for the production of composite materials. Control over ice growth remains a challenge in industry, and the demand for new cryoprotectants is high. Naturally occurring cryoprotectants, such as antifreeze proteins (AFPs), present one solution for ...

Bottom-up, top-down

Bottom-Up Beats Top-Down

In PEPA, the calculation of the transitions enabled by a process accounts for a large part of the time for the state space exploration of the underlying Markov chain. Unlike other approaches based on recursion, we present a new technique that is iterative—it traverses the process’ binary tree from the sequential components at the leaves up to the root. Empirical results shows that this algorith...