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ABSTRACT Bubble nucleation associated with nucleate boiling at superheated surfaces has typically focused on surfaces with features on the order of microns and bubble embryos with comparable interface radii of curvature. For such surfaces the vapor embryo growth or collapse behavior is consistent with surface tension and wetting forces being confined to the contact line region at the surface. In a pure fluid saturating a superheated nanopororus layer, random density fluctuations can lead to the formation of nanoscale bubble embryos. Said fluctuations increase as the liquid is superheated and can lead to macroscopic nucleation. Entrapment of gas when nanostructured surfaces are flooded with liquid can also result in nanoscale bubble embryos in or near the porous layer. For highly wetted nanostructured surfaces, the fluid-to-surface attractive forces are strong over much of a nanobubble embryo, and the critical bubble size that results in spontaneous bubble growth is affected more strongly by surface forces. A Lattice Boltzmann model (LBM) is used to simulate the time evolution behavior of bubble embryos, with radii ranging from 5 to 15 nanometers, close to or within nanoscale interstitial spaces of a nanostructured surface. Single vapor nanobubbles are seeded in surrounding fluid with varying degrees of contact with solid surfaces to simulate smooth or nanostructured surfaces. The effects of varying adsorption coefficient (which dictates contact angle), varying bubble surface radius of curvature, mean distance of wall nanostructures from the embryo, and varying degrees of enclosure of the embryo by surrounding wall structures are explored. The simulation results indicate that the critical radius is largely impacted by the proximity of nanostructures, demonstrating how the fluid-surface forces affect the stability of a vapor embryo. The results suggest that the hydrophilic nature of the surfaces contributes to the suppression in the onset of nucleate boiling which is often seen in hydrophilic nanoporous layers. The implications of these results on convective and nucleate boiling at and within nanostructured surfaces are also discussed. 

We present predictions and postdictions for a wide variety of hard jet-substructure observables using a multistage model within the framework. The details of the multistage model and the various parameter choices are described in []. A novel feature of this model is the presence of two stages of jet modification: a high-virtuality phase [modeled using the modular all twist transverse-scattering elastic-drag and radiation model ()], where modified coherence effects diminish medium-induced radiation, and a lower virtuality phase [modeled using the linear Boltzmann transport model ()], where parton splits are fully resolved by the medium as they endure multiple scattering induced energy loss. Energy-loss calculations are carried out on event-by-event viscous fluid dynamic backgrounds constrained by experimental data. The uniform and consistent descriptions of multiple experimental observables demonstrate the essential role of modified coherence effects and the multistage modeling of jet evolution. Using the best choice of parameters from [], and with no further tuning, we present calculations for the medium modified jet fragmentation function, the groomed jet momentum fraction $z_g$and angular separation $r_g$distributions, as well as the nuclear modification factor of groomed jets. These calculations provide accurate descriptions of published data from experiments at the Large Hadron Collider. Furthermore, we provide predictions from the multistage model for future measurements at the BNL Relativistic Heavy Ion Collider. Published by the American Physical Society2024 

The problem of detecting anomalies in time series from network measurements has been widely studied and is a topic of fundamental importance. Many anomaly detection methods are based on packet inspection collected at the network core routers, with consequent disadvantages in terms of computational cost and privacy. We propose an alternative method in which packet header inspection is not needed. The method is based on the extraction of a normal subspace obtained by the tensor decomposition technique considering the correlation between different metrics. We propose a new approach for online tensor decomposition where changes in the normal subspace can be tracked efficiently. Another advantage of our proposal is the interpretability of the obtained models. The flexibility of the method is illustrated by applying it to two distinct examples, both using actual data collected on residential routers. 

Dislocations are one-dimensional defects in crystals, enabling their deformation, mechanical response, and transport properties. Less well known is their influence on material chemistry. The severe lattice distortion at these defects drives solute segregation to them, resulting in strong, localized spatial variations in chemistry that determine microstructure and material behavior. Recent advances in atomic-scale characterization methods have made it possible to quantitatively resolve defect types and segregation chemistry. As shown here for a Pt-Au model alloy, we observe a wide range of defect-specific solute (Au) decoration patterns of much greater variety and complexity than expected from the Cottrell cloud picture. The solute decoration of the dislocations can be up to half an order of magnitude higher than expected from classical theory, and the differences are determined by their structure, mutual alignment, and distortion field. This opens up pathways to use dislocations for the compositional and structural nanoscale design of advanced materials. 

Abstract: A colorimetric indicator displacement assay (IDA) amenable to high-throughput experimentation was developed to determine the percentage of cis and trans alkenes. Using 96-well plates two steps are performed: a reaction plate for dihydroxylation of the alkenes followed by an IDA screening plate consisting of an indicator and a boronic acid. The dihydroxylation generates either erythro or threo vicinal diols from cis or trans alkenes, depending upon their syn- or antiaddition mechanisms. Threo diols preferentially associate with the boronic acid due to the creation of more stable boronate esters, thus displacing the indicator to a greater extent. The generality of the protocol was demonstrated using seven sets of cis and trans alkenes. Blind mixtures of cis and trans alkenes were made, resulting in an average error of 2% in the percentage of cis or trans alkenes, and implementing E2 and Wittig reactions gave errors of 3%. Furthermore, we developed variants of the IDA for which the color may be tuned to optimize the response for the human eye.