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A computational model is developed to describe convection in volatile liquids evaporating in capillary tubes. Experimental work has demonstrated the existence of such convective structures. The correlation between this convection and the phase change process has been experimentally established. Temperature distribution on the liquid‐vapour interface is considered in order to characterise the minimum of radial temperature gradient required to initiate and orientate Marangoni convection. Direct numerical simulation using finite volume approximation is used to investigate the heat and mass transfer in the liquid phase. The case of a capillary tube filled with a volatile liquid is investigated for various Marangoni numbers, to characterise heat and mass transfers under conditions close to realistic operating parameters. The simulation shows that a minimum irregularity in evaporative flux along the liquid‐vapour interface is necessary to trigger thermocapillary convection. The enhancement of heat and mass transfer by Marangoni convection is also investigated.

The purpose of this study is to establish an effective numerical simulation method to describe the flow pattern and optimize the strategy of noncontact mixing induced by alternating Gaussian light inside a nanofluid droplet and analyzing the influencing factors and flow mechanism of fluid mixing inside a droplet.

First, the heat converted by the alternating incident Gaussian light acting on the nanoparticles was considered as the bulk heat source distribution, and the equilibrium equation between the surface tension and the viscous force at the upper boundary force was established; then, the numerical simulation methods for multiple-physical-field coupling was established, and the mixing index was used to quantify the mixing degree inside a droplet. The effects of the incident position of alternating Gaussian light and the height of the droplet on the mixing characteristics inside a droplet were studied. Finally, the nondimensional Marangoni number was used to reveal the flow mechanism of the internal mixing of the droplet.

Noncontact alternating Gaussian light can induce asymmetric vortex motion inside a nanofluid droplet. The incident position of alternating Gaussian light is a significant factor affecting the mixing degree in the droplet. In addition, the heat transfer caused by the surface tension gradient promotes the convection effect, which significantly enhances the mixing of the fluid in the droplet.

This study demonstrates the possibility of the chaotic mixing phenomenon induced by noncontact Gaussian light that occurs within a tiny droplet and provides a feasible method to achieve efficient mixing inside droplets at the microscale.

The present study aims to investigate the inverse-thermocapillary effect in an evaporating thin liquid film of self-rewetting fluid, which is a dilute aqueous solution (DAS) of long-chain alcohol.

A long-wave evolution model modified for self-rewetting fluids is used to study the inverse thermocapillary characteristics of an evaporating thin liquid film. The flow attributed to the inverse thermocapillary action is manifested through the streamline plots and the evaporative heat transfer characteristics are quantified and analyzed.

The thermocapillary flow induced by the negative surface tension gradient drives the liquid from a low-surface-tension (high temperature) region to a high-surface-tension (low temperature) region, retarding the liquid circulation and the evaporation strength. The positive surface tension gradients of self-rewetting fluids induce inverse-thermocapillary flow. The results of different working fluids, namely, water, heptanol and DAS of heptanol, are examined and compared. The thermocapillary characteristic of a working fluid is significantly affected by the sign of the surface tension gradient and the inverse effect is profound at a high excess temperature. The inverse thermocapillary effect significantly enhances evaporation rates.

The current investigation on the inverse thermocapillary effect in a self-rewetting evaporating thin film liquid has not been attempted previously. This study provides insights on the hydrodynamic and thermal characteristics of thermocapillary evaporation of self-rewetting liquid, which give rise to significant thermal enhancement of the microscale phase-change heat transfer devices.

The purpose of this study is to use a weak light source with spatial distribution to realize light-driven fluid by adding high-absorbing nanoparticles to the droplets, thereby replacing a highly focused strong linear light source acting on pure droplets.

First, Fe₃O₄ nanoparticles with high light response characteristics were added to the droplets to prepare nanofluid droplets, and through the Gaussian light-driven flow experiment, the Marangoni effect inside a nanofluid droplet was studied, which can produce the surface tension gradient on the air/liquid interface and induce the vortex motion inside a droplet. Then, the numerical simulation method of multiphysics field coupling was used to study the effects of droplet height and Gaussian light distribution on the flow characteristics inside a droplet.

Nanoparticles can significantly enhance the light absorption, so that the Gaussian light is enough to drive the flow, and the formation of vortex can be regulated by light distribution. The multiphysics field coupling model can accurately describe this problem.

This study is helpful to understand the flow behavior and heat transfer phenomenon in optical microfluidic systems, and provides a feasible way to construct the rapid flow inside a tiny droplet by light.

Online charitable giving is prevalent, and how to attract individuals' attention to donate is essential for charities. Little is known about the interaction effect of empathy (donor) and vulnerability (receiver) on donate intention. To bridge this gap, this study aims to investigate whether the influence of empathy on charitable giving would be moderated by receivers' vulnerability, and if yes, what is the mechanism.

Five experiments were conducted in the context of charitable giving with 1,303 participants to test our hypotheses.

When empathetic individuals confronted high vulnerable receivers, they were less likely to donate; otherwise, they were more likely to donate when they confronted low vulnerable receivers, and this interaction effect was mediated by concern about self.

The present research identifies a novel moderator of the effect of empathy on charitable giving and elucidates the underlying mechanism of concern about self. Based on these findings, the authors provide actionable implications for charities by demonstrating the interaction effect of empathy and vulnerability on donate intention.

This paper aims to draw attention to an urgent need for reform of the regulatory framework of the broader export credit system to ensure a new and comprehensive “safe haven” for officially supported export credits. The purpose is to analyse the complex debate on disciplines of the World Trade Organization (WTO) and the Organisation for Economic Co-operation and Development (OECD), creating a point of reference for future analysis of and debates around the “carve-out clause” of the Agreement on Subsidies and Countervailing Measures (ASCM) and a “safe haven” in a broader sense.

This paper takes inspiration from legal, economic and political science literature on subsidies and officially supported export credits, as well as on legal documents related to the WTO and the OECD. It examines the WTO subsidy and the OECD export credits framework, focusing on main legal and economic governance aspects. Then, it gives a critical analysis how “safe” a “safe haven” in a broader sense might be, assessing frictions of and solutions for the fundamentally different set of disciplines, limitations, financial instruments not covered by OECD regulations, as well as new challenges related to climate finance.

After assessing the challenges regarding the “carve-out clause” of the WTO subsidy framework and two tracks aiming to create a new “safe haven”, requirements for comprehensive disciplines for officially supported export credits are pointed out. Furthermore, several misunderstandings and mistakes appearing in the debate are clarified.

Desktop research rather than empirical field work.

This paper creates awareness for governments and exporters how to deal with a complex system of interrelated disciplines. The question, how “safe” a “safe haven” in a broader sense can be, has not been resolved yet. Some authors focus on the WTO disciplines not taking into account the need for an effective matching procedure of the Arrangement on Officially Supported Export Credits (the Arrangement). Furthermore, the introduction of several new pre-export financing programmes and the growing significance of climate finance-related instruments for export credit agencies creates both opportunities and challenges. This paper can serve as a reference point for the academic debate and further research. This paper also offers newcomers to the topic a comprehensive overview.

Although the “carve-out clause” and the Arrangement have been much discussed, there is limited literature review structuring both existing and new aspects of the debate, assessing (dis)advantages of arguments and interpretations. This paper both adds to the corpus of literature about the ASCM, as well as the Arrangement, and takes this corpus as the object of its analysis.

How might the profession of child protection social work be “future proofed”, i.e. remain intact and of value beyond its present existence? The paper aims to discuss this issue.

This is a discussion/“think piece” paper, in which the author argues that foregrounding the art and science of helping relationships is a way forward. Recognising and promoting the centrality of helping relationships is the direction in which the author believes (or is it hopes?) social work should head, because “more of the same” is not, in the author’s view, possible to sustain for much longer. Treading the well-worn but pot-holed path of box-ticking, endless risk assessment and perfunctory statutory visiting is likely to lead to continuing problems retaining social workers and, for those who do stay, increased burnout, compassion fatigue and secondary trauma, each of which interrupts or delays the development of working alliances with family members.

Growing reliance on thresholds and checklists to assess risk has served to increase referrals. As a result, social workers spend much of their time on triaging and filtering rather than working with the children and families that most need help and protection. Further, it is not what is in the practitioner’s toolkit that matters: rather, it is a defined set of personal skills and qualities that tips the balance to achieve lasting change. Thus, in order to “future proof” social work, we would do well to deepen our understanding of how helping relationships can lead to lasting change. Supporting social workers in this work is not just the responsibility of individual practitioners and their professional bodies, action also needs to be taken at governmental and managerial levels.

This is a discussion/“think piece”.

This paper aims to describe librarians’ efforts in reaching out to international students through vernacular language videos at both the University of Colorado Boulder and the University of Oregon. The videos were created to help international students familiarize themselves with the new library environment and to stimulate their interest in the future exploration of library resources and services.

This paper discusses the challenges of providing effective support to international students in the early stages of their academic life in the USA, explains the rationale for using vernacular language videos as a means of outreach to international students, outlines the factors considered in designing the videos that helped achieve the outreach goals and reviews promotion needs and assessment methods for evaluating the effectiveness of the videos.

Using online videos in native languages as a means to extend the reach of the libraries to international students is seen as useful and practical. Feedback from students and library colleagues shows positive reaction to the videos and provides encouragement for further outreach efforts to international students.

The strategies and experiences detailed here are easily adaptable to other institutions of higher education committed to developing outreach programs for international students.

The novelty of this case study is the librarians’ sophisticated thinking in developing vernacular language videos as a means of outreach to international students. The video project presented in the paper can function as an inspiring example for institutions preparing for the expected large influx of international students.

The anonymity of the Internet supports an increasing number of deviant behaviors such as secret affairs. This paper aims to investigate whether religiosity has a negative relationship with the incidence of secret affairs in cyberspace and how it moderates the substitution effect between the use of online and off-line channels for such deviant behaviors.

The authors constructed a cross-sectional county-level dataset containing data on US religious adherents' ratios and actual expenditures on a social website related to extramarital affairs. The data were analyzed by ordinary least squares and two-stage least squares regression models.

In general, religiosity has a negative relationship with secret affairs in cyberspace. It also moderates the relationship between using online (secret affairs websites) and off-line (entertainment facilities) channels for extramarital affairs. The deterrent effect of religiosity is weakened in religious communities with diversified religious teachings/structures and stricter requirements.

This work enriches the understanding of the role of religiosity in online deviant behaviors and provides essential insights for policymakers (e.g. in relation to spillover effects of social norms in cyberspace).

This study aims to examine the relations between service employee blame attributions in response to customer incivility and revenge desires and revenge behavior toward customers, and whether employee empathy moderated these relations.

The authors used survey data based on the critical incident method provided by a sample of 431 customer service employees.

The results suggested that blaming a customer was positively associated with desire for revenge and revenge behaviors against the uncivil customer. In addition, the authors found that blame was less strongly associated with desire for revenge when employees empathized with customers. Finally, the results show that an employee who desired revenge against the uncivil customer and who empathized with the customer was more – not less – likely to engage in revenge.

The authors found that when employees experience mistreatment from customers, it increases the likelihood that they will blame the offending customer and behave in ways that are contrary to their organization’s interests. The results suggest several points of intervention for organizations to more effectively respond to customer mistreatment.

In this study, the authors make one of the first attempts to investigate the relationships between service employee attributions of blame when they experience customer incivility, desire for revenge and customer-directed revenge behaviors. The authors also examined whether empathy moderates the relations between blame attribution, desires for revenge and revenge behavior.