Correction: Self-diffusion, velocity cross-correlation, distinct diffusion and resistance coefficients of the ionic liquid [BMIM][Tf2N] at high pressure

Correction for ‘Self-diffusion, velocity cross-correlation, distinct diffusion and resistance coefficients of the ionic liquid [BMIM][Tf2N] at high pressure’ by Kenneth R. Harris et al., Phys. Chem. Chem. Phys., 2015, 17, 23977–23993, DOI: 10.1039/C5CP04277A.

Investigation of the concentration- and temperature-dependent motion of colloidal nanoparticles

Laser speckle imaging is used to study the influence of concentration and temperature on the motion of suspended gold nanoshells. Long-range interparticle interaction and viscosity of the dispersing medium sizeably affect the diffusion velocity.

Experimental Study of Aerosol Behavior During Pool Scrubbing: Part 1 — Visualization Measurement of Aerosol Particle in a Single Rising Bubble

As pool scrubbing plays an important role in fission product (FP) decontamination, a reliable model is needed. Despite the needs, mechanism of FP transfer from air-water from the swarm is not explained exactly which means that the evaluation of physical model used in pre-existing model couldn’t be done enough. Existing model for pool scrubbing is predicted in the MELCOR code. Inside the code, a simple model of bubbly jet divided in 3 regions is used: 1) Globule region where the gas including FP enter and collapse, 2) Swarm rise region where the bubble rises up stationary after the collapse is done and, 3) Entrainment region where the bubble pop out to the atmosphere. In each region, the decontamination factor (DF), the particle density ratio before and after each region, is calculated. On these region, flow and physical force inside the gas phase is predicted to be one of the driving force which cause the FP transfer. Therefore, our study aims at the particle behavior on the gas phase. As to understand the physical phenomenon individually, the study focuses on flow behavior and inner flow of a single rising bubble. As an approach, comparison of bubble containing aerosol and no aerosol has been done for each parameter of size, aspect ratio, velocity. Compared with existing equations, the rising speed of clean bubble condition and aspect ratio of CSI condition agreed well to the MELCOR code [1]. On the other hand, many difference were also measured in other condition. Application of parameters obtained from experiment were done against the MELCOR model. Calculation of velocity inside the oil droplet using the experimental parameters obtained from visualization measurement was done. The local gravitational sedimentation and centrifugal velocity took a higher value in clean bubble and OX50 condition compared to CSI condition. On the other hand, Brownian diffusion velocity had an opposite trend. PIV measurement were performed by a silicone oil to visualize the inner flow clearly and compared with the calculation. Seen from the results, the local diffusion velocity took a lower value compared to the calculation using the MELCOR model.

Magnetic field configurations of magnetars

We evaluated ambipolar diffusion velocity in a magnetar. Previous studies concerning ambipolar diffusion ignored the presence of the crust, although a magnetar has both core and crust. We considered both core and crust and examined the influence of the crust in this study. We found that the crustal magnetic field can accelerate the ambipolar diffusion in its core.

Spatio-temporal dynamics of web pages diffused in WeChat

Purpose WeChat is the largest acquaintance social networking platform in China, in which users can view and reshare web pages shared by friends. This paper aims to analyze the spatio-temporal dynamics of web pages diffused in WeChat and advice on commercials. Design/methodology/approach A large number of web pages diffused in WeChat are collected and exclusively divided into four categories according to their titles, including advertisements, news bulletins, holiday greetings and emotional essays. For each web page, an information cascade (tree structure) is constructed to describe the diffusion trace. Based on the categories, the spatio-temporal popularity is characterized; the topological, temporal and spatial properties are examined; and the spatio-temporal diffusion velocity is explored. Findings Through comparative analysis, different categories of pages show diversity. For spatio-temporal popularity, there is no significant difference in cascade size; holiday greetings usually last for a relatively short time on average; emotional essays are more likely to spread to more provinces. For topological, temporal and spatial characteristics, the diffusion process of advertisements is more likely to be broadcasting than other categories; news bulletins and holiday greetings have an obvious bursty; the number of viewing behavior decreases from east to west in general. For spatio-temporal diffusion velocity, emotional essays diffuse the fastest in topological and spatio-temporal dimensions. Originality/value These findings contribute to promoting products and providing support for data driven modeling of information diffusion and human activity in spatio-temporal dimensions.

A Phase-Field Model for Rapid Solidification with Non-Equilibrium Solute Diffusion

Since the growth velocity can be comparable with or even larger than the solute diffusion velocity in the bulk phases, modeling of rapid solidification with non-equilibrium solute diffusion becomes quite an important topic. In this paper, an effective mobility approach was proposed to derive the current phase field model (PFM). In contrast with the previous PFMs that were derived by the so-called kinetic energy approach, diffusionless solidification happens not only in the bulk phases but also inside the interface when the growth velocity is equal to the solute diffusion velocity in liquid. A good agreement between the model predictions and experimental results is obtained for rapid solidification of Si-9at.%As alloy.