Study of Prenucleation Ion Clusters: Correlation between Ion Mobility Spectra and Size Distributions

Additional studies regarding our earlier electrothermodynamic theory are presented. Comparisons to recent expansion cloud chamber ion mobility measurements are made, indicating general agreement with observations. This theory predicts more stable and ordered structure for prenucleation ion-water cluster systems than accounted for by the classical Thomson\u27s theory. In the limiting case of the dielectric constant ε = 1, our monopole electrostatic energy term contributed by the foreign ion center precisely converges to that of Thomson. Predicted ion cluster size distributions are found to correlate well with ion cluster size spectra obtained from the ion mobility measurements of hydrated ion clusters and Champman-Enskog theory. In view of good correlation between the theory and observation, we believe that ion mobility study at sufficiently low electric field is a powerful tool for studying prenucleation dynamics

Pressure and Temperature Effects on the Energy of Formation for Silicon Clusters

At present most theoretical studies of atomic clusters are limited to their physical properties referred to 0 K. To the best of our knowledge, there exists no theoretical study of the simultaneous dependence of cluster formation and cluster-size distributions on both pressure and temperature. In the present work both pressure and temperature effects on the formation of silicon clusters are explored. A universal semiempirical formula is obtained to show a general trend in the variation of binding energy as a function of cluster size for both atomic and molecular clusters

Lanczos exact diagonalization study of field-induced phase transition for Ising and Heisenberg antiferromagnets

Using an exact diagonalization treatment of Ising and Heisenberg model Hamiltonians, we study field-induced phase transition for two-dimensional antiferromagnets. For the system of Ising antiferromagnet the predicted field-induced phase transition is of first order, while for the system of Heisenberg antiferromagnet it is the second-order transition. We find from the exact diagonalization calculations that the second-order phase transition (metamagnetism) occurs through a spin-flop process as an intermediate step.Comment: 4 pages, 4 figure

Role of spinon and spinon singlet pair excitations on phase transitions in d−waved-wave superconductors

We examine the roles of massless Dirac spinon and spin singlet pair excitations on the phase transition in $d-wave$ superconductors. Although the massless spinon excitations in the presence of the spin singlet pair excitations do not alter the nature of the phase transition at $T = 0$, that is, the XY universality class, they are seen to induce an additional attractive interaction potential between vortices, further stabilizing vortex-antivortex pairs at low temperature for lightly doped high $T_c$ samples.Comment: 5 pages, 1 figur

Current Questions in Nucleation Theory

This poster session paper discusses the nucleation process in the formation of aerosols. Expansion cloud chamber technique for the measurement of homogeneous nucleation rates was developed

Region of Interest Selection Interface for Wide-Angle Arthroscope

We have proposed a new interface for an wide-angle endoscope for solo surgery. The wide-angle arthroscopic view and magnified region of interest (ROI) within the wide view were shown simultaneously. With a camera affixed to surgical instruments, the position of the ROI could be determined by manipulating the surgical instrument. Image features acquired by the A-KAZE approach were used to estimate the change of position of the surgical instrument by tracking the features every time the camera moved. We examined the accuracy of ROI selection using three different images, which were different-sized square arrays and tested phantom experiments. When the number of ROIs was twelve, the success rate was best, and the rate diminished as the size of ROIs decreased. The experimental results showed that the method of using a camera without additional sensors satisfied the appropriate accuracy required for ROI selection, and this interface was helpful in performing surgery with fewer assistants

Region of Interest Selection Interface for Wide-Angle Arthroscope

We have proposed a new interface for an wide-angle endoscope for solo surgery. The wide-angle arthroscopic view and magnified region of interest (ROI) within the wide view were shown simultaneously. With a camera affixed to surgical instruments, the position of the ROI could be determined by manipulating the surgical instrument. Image features acquired by the A-KAZE approach were used to estimate the change of position of the surgical instrument by tracking the features every time the camera moved. We examined the accuracy of ROI selection using three different images, which were different-sized square arrays and tested phantom experiments. When the number of ROIs was twelve, the success rate was best, and the rate diminished as the size of ROIs decreased. The experimental results showed that the method of using a camera without additional sensors satisfied the appropriate accuracy required for ROI selection, and this interface was helpful in performing surgery with fewer assistants