Patterned carbon nanotube growth using an electron beam sensitive direct writable catalyst.

This paper reports the use of spin coatable Fe naphthenate (Fe(C(11)H(7)O(2))(2)) as an electron beam sensitive direct writable catalyst suitable for growing high quality carbon nanotubes (CNTs). Vertically aligned, densely packed, equal in height, three- to four-walled and 5-7 nm inner diameter CNTs were grown on the nanoscale stripe patterns by water-assisted chemical vapor deposition. The correlation between electron beam dosage and the growth characteristics of CNTs is also discussed.

Role of solvent for globular proteins in solution.

The properties of the solvent affect the behavior of the solution. We propose a model that accounts for the contribution of the solvent free energy to the free energy of globular proteins in solution. For the case of an attractive square-well potential, we obtain an exact mapping of the phase diagram of this model without solvent to the model that includes the solute-solvent contribution. In particular we find for appropriate choices of parameters upper critical points, lower critical points, and even closed loops with both upper and lower critical points similar to those found before [Macromolecules 36, 5843 (2003)]. In the general case of systems whose interactions are not attractive square wells, this mapping procedure can be a first approximation to understand the phase diagram in the presence of solvent. We also present simulation results for both the square-well model and a modified Lennard-Jones model.