Infiltration behaviour of water in a carbon nanotube under external pressure

The wetting behaviour and associated pressure effect of water in single-walled carbon nanotubes (SWCNTs) are investigated through molecular dynamics (MD) simulations. It is found that water molecules can enter SWCNTs via surface diffusion, and the effective infiltration rate increases with pressure. The effect of pressure on infiltration rate is highly non-linear, exhibiting characteristics of both hydrophilic and hydrophobic surfaces. There exists a nominal infiltration pressure that is dependent on the SWCNT size, above which the water flux is significantly increased.     

Surface tension of substantially undercooled liquid Ti–Al alloy

It is usually difficult to undercool Ti–Al alloys on account of their high reactivity in the liquid state. This results in a serious scarcity of information on their thermophysical properties in the metastable state. Here, we report on the surface tension of a liquid Ti–Al alloy under high undercooling condition. By using the electromagnetic levitation technique, a maximum undercooling of 324 K (0.19 T _L) was achieved for liquid Ti-51 at.% Al alloy. The surface tension of this alloy, which was determined over a broad temperature range 1429–2040 K, increases linearly with the enhancement of undercooling. The experimental value of the surface tension at the liquidus temperature of 1753 K is 1.094 N m^?1 and its temperature coefficient is ?1.422 × 10^?4 N m^?1 K^?1. The viscosity, solute diffusion coefficient and Marangoni number of this liquid Ti–Al alloy are also derived from the measured surface tension.     

Local translational order in the icosahedral quasicrystalline phase of V41Ni36Si23

Abstract

The local translational order of the icosahedral quasicrystalline phase in rapidly solidified V₄₁Ni₃₆Si₂₃ has been investigated by means of selected-area electron diffraction and high-resolution electron microscopy. Experimental results show that translational order always occurs in the twofold direction and can be observed when the quasicrystal is examined along its fivefold and threefold as well as twofold axes. Sometimes it occurs in two or three coplanar twofold directions simultaneously. In these cases some crystalline islands exist in the icosahedral quasicrystal and this corresponds to the initial stage of transformation from a quasicrystal to the stable crystalline phase.     

Characteristics of Unintentional Movements by a Multijoint Effector

The authors explored the phenomenon of unintentional changes in the equilibrium state of a multijoint effector produced by transient changes in the external force. The subjects performed a position-holding task against a constant force produced by a robot and were instructed not to intervene voluntarily with movements produced by changes in the robot force. The robot produced a smooth force increase leading to a hand movement, followed by a dwell time. Then, the force dropped to its initial value leading to hand movement toward the initial position, but the hand stopped short of the initial position. The undershoot magnitude increased linearly with the peak hand displacement and exponentially with dwell time (time constant of about 1 s). For long dwell times, the hand stopped at about half the total distance to the initial position. The authors interpret the results as consequences of a drift of the referent hand coordinate. Our results provide support for back-coupling between the referent and actual body configurations during multijoint actions and produce the first quantitative analysis of this phenomenon. This mechanism can also explain the phenomena of slacking and force drop after turning visual feedback off during accurate force production task.     

Different Strokes for Different Folks: The Impact of Sex Dissimilarity in the Empowerment–Performance Relationship

Organizations often utilize empowerment as a way to bolster performance. It is largely assumed, however, that its impact in this capacity is equivalent across organizational members. We tested this notion within a sample of 420 employees belonging to 75 teams in a Chinese organization and found that team empowerment related positively to supervisor‐rated in‐role and self‐rated extra‐role performance through its effect on individual psychological empowerment. More important, employee–coworker demographic dissimilarity moderated both stages of this indirect relationship. Specifically, when employee–coworker sex dissimilarity was higher, the following relationships were attenuated: (a) team empowerment–individual empowerment, (b) individual empowerment–in‐role performance, and (c) individual empowerment–extra–role performance. Collectively, the results illustrate that the impact of empowerment is contingent upon demographic dissimilarity.     

A Hierarchical Modeling Approach to Data Analysis and Study Design in a Multi-site Experimental fMRI Study

We propose a hierarchical Bayesian model for analyzing multi-site experimental fMRI studies. Our method takes the hierarchical structure of the data (subjects are nested within sites, and there are multiple observations per subject) into account and allows for modeling between-site variation. Using posterior predictive model checking and model selection based on the deviance information criterion (DIC), we show that our model provides a good fit to the observed data by sharing information across the sites. We also propose a simple approach for evaluating the efficacy of the multi-site experiment by comparing the results to those that would be expected in hypothetical single-site experiments with the same sample size.     

书法练习对儿童情绪及其调节策略发展的促进作用

本研究采用纵向设计,对170名儿童（实验组：101人;对照组：69人）进行为期两学年的追踪,旨在探讨书法练习对儿童情绪状态及认知性情绪调节策略发展的影响。研究发现,1）以前测成绩为协变量,后测时实验组的积极情绪显著高于对照组;2）实验组在“积极重新关注”、“计划”两维度上的情绪调节策略得分增量（后测-前测）显著高于对照组。结果表明,书法练习对儿童情绪及其调节策略发展具有促进作用。