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Thus far, I have introduced the reader to evidence based practice in a broad sense, and evidence based relationships across important variables. In this chapter, I further build on this by extending the need for evidence based responsiveness as applied to client factors. While the practitioner brings themselves and their bag of tools to the therapy encounter, the client brings not just their presenting problem, but their characteristic way of thinking about their problems and how they manage distress and change. Therefore, the supportive practitioner will be best served to understand how these client factors manifest for each individual that they work with. The purpose of this chapter then, is to discuss coping style, reactant level, stage of change, attachment style, and client preferences, within the context of the practitioner being responsive to these factors as they impact on therapy outcomes.

Effective performance of a direct ethanol fuel cell (FC) stack depends on the satisfactory operation of its individual cells where it is always challenging to manage the temperature gradient, water flow and distribution of reactants. In that, the design of the bipolar fuel flow path plate plays a vital role in achieving the aforementioned parameters. Further, the bipolar plates contribute 80% of the weight and 30%–40% of its total cost. Aim of this study is to enhance the efficiency of fuel to energy conversion and to minimize the overall cost of production.

The authors have specifically designed, simulated and fabricated a standard 2.5 × 2.5 cm² active area proton exchange membrane (PEM) FC flow path plate to study the performance by varying the flow fields in a single ladder, double ladder and interdigitated and varying channel geometries, namely, half curve, triangle and rectangle.

Using the 3D PEMFC model and visualizing the physical and electrochemical processes occurring during the operation of the FCs resulted in a better-performing flow path plate design. It is fabricated by using additive manufacturing technology. In addition, the assembly of the full cell with the designed flow path plate shows about an 11.44% reduction in total weight, which has a significant bearing on its total cost as well as specific energy density in the stack cell.

Simultaneous optimization of multiple flow path parameters being carried out for better performance is the hallmark of this study which resulted in enhanced energy density and reduced cost of device production.

The purpose of this paper is to introduce and analyze a new blast-wave impact-mitigation concept using advanced computational methods and tools. The concept involves the use of a protective structure consisting of bimolecular reactants displaying a number of critical characteristics, including: a high level of thermodynamic stability under ambient conditions (to ensure a long shelf-life of the protective structure); the capability to undergo fast/large-yield chemical reactions under blast-impact induced shock-loading conditions; large negative activation and reaction volumes to provide effective attenuation of the pressure-dominated shockwave stress field through the volumetric-energy storing effects; and a large activation energy for efficient energy dissipation. The case of a particular bimolecular chemical reaction involving polyvinyl pyridine and cyclohexyl chloride as reactants and polyvinyl pyridinium ionic salt as the reaction product is analyzed.

Direct simulations of single planar shockwave propagations through the reactive mixture are carried out, and the structure of the shock front examined, as a function of the occurrence of the chemical reaction. To properly capture the shockwave-induced initiation of the chemical reactions during an impact event, all the calculations carried out in the present work involved the use of all-atom molecular-level equilibrium and non-equilibrium reactive molecular-dynamics simulations. In other words, atomic bonding is not pre-assigned, but is rather determined dynamically and adaptively using the concepts of the bond order and atomic valence.

The results obtained clearly reveal that when the chemical reactions are allowed to take place at the shock front and in the shockwave, the resulting shock front undergoes a considerable level of dispersion. Consequently, the (conserved) linear momentum is transferred (during the interaction of the protective-structure borne shockwaves with the protected structure) to the protected structure over a longer time period, while the peak loading experienced by the protected structure is substantially reduced.

To the authors’ knowledge, the present work is the first attempt to simulate shock-induced chemical reactions at the molecular level, for purposes of blast-mitigation.

In the recent work, a new blast-wave impact-mitigation concept involving the use of a protective structure consisting of bimolecular reactants (polyvinyl pyridine+cyclohexyl chloride), capable of undergoing a chemical reaction (to form polyvinyl pyridinium ionic salt) under shockwave loading conditions, was investigated using all-atom reactive equilibrium and non-equilibrium molecular-dynamics analyses. The purpose of this paper is to reveal the beneficial shockwave dispersion/attenuation effects offered by the chemical reaction, direct simulations of a fully supported single planar shockwave propagating through the reactive mixture were carried out, and the structure of the shock front examined as a function of the extent of the chemical reaction (i.e. as a function of the strength of the incident shockwave). The results obtained clearly revealed that chemical reactions give rise to considerable broadening of the shockwave front. In the present work, the effect of chemical reactions and the structure of the shockwaves are investigated at the continuum level.

Specifically, the problem of the (conserved) linear-momentum accompanying the interaction of an incident shockwave with the protective-structure/protected-structure material interface has been investigated, within the steady-wave/structured-shock computational framework, in order to demonstrate and quantify an increase in the time period over which the momentum is transferred and a reduction in the peak loading experienced by the protected structure, both brought about by the occurrence of the chemical reaction (within the protective structure).

The results obtained clearly revealed the beneficial shock-mitigation effects offered by a protective structure capable of undergoing a chemical reaction under shock-loading conditions.

To the authors’ knowledge, the present manuscript is the first report dealing with a continuum-level analysis of the blast-mitigation potential of chemical reactions.

This research aims to demonstrate that coupons with short durations for redemption can backfire, lowering consumers’ attitudes toward the company.

Two experimental studies in the restaurant context demonstrate the backfire effect. A boundary condition of the effect as well as the underlying psychological process are identified.

Consumers respond adversely to coupons with restrictive requirements for redemption – in particular, a short duration. Study 1 indicates that while a short-duration (vs long-duration) coupon may backfire when its face value is low, this backfire effect is attenuated when the coupon’s face value is high. Furthermore, Studies 1 and 2 provide evidence that psychological reactance is the process underlying this backfire effect.

Consumers respond negatively to coupons with restrictive requirements for redemption because they perceive them as a company’s attempt to limit their freedom of choice. Companies should take measures, including careful target marketing, to avoid rousing this reaction from their consumers.

Focusing on firm-initiated brand communities, the purpose of this paper is to systematically examine the influence of brand community rejection on consumer evaluations and document the underlying mechanism involved.

Four empirical studies were conducted to test the proposed hypotheses. Using a similar 2 × 2 study design, different subject samples and different product categories, Studies 1-3 investigated whether a brand community rejection strategy impacted strong brands differently than weak brands. Furthermore, Study 3 measured reactance as a moderator to explore the underlying process of the impact of a brand community rejection strategy on brand evaluations for different types of brands (i.e. strong vs weak). Study 4 used a 2 × 2 × 2 between-subjects design to examine whether justification would eliminate the negative impact of brand community rejection on subsequent brand evaluations for a weak brand.

Across the four studies, the findings consistently suggest that rejection from firm-initiated brand communities harms weak brands but not strong brands. In addition, by incorporating psychological reactance as a moderator of this effect, the authors uncover the process underlying the interaction between brand community rejection and brand strength. Furthermore, the paper examines the reasons that justify rejection to find a solution that eliminates the negative impact of brand community rejection on brand evaluations for weak brands.

To the best of the authors’ knowledge, this research provides the first investigation of the effects of a brand community rejection strategy for different brands. The findings could advance the social exclusion literature and shed new light on brand community research.

This paper aims to investigate the situational and personal aspects that may trigger smokers’ psychological state reactance. It was hypothesized that situational factors, such as perceived threat to freedom and perceived loss of control, which are supposed to be triggered by an anti-smoking persuasive message, and a personality pattern, such as trait reactance proneness, predict the psychological state reactance.

An experiment and a survey were conducted on a random sample of 246 smoking undergraduate students in two Tunisian business schools. Four anti-smoking print ads, with two different levels of negative emotional intensity, were manipulated.

The findings depict the importance of the anti-smoking ads with a high negative emotional intensity, the perceived threat to freedom and trait reactance proneness in the smokers’ psychological reactance prediction.

This work seems to be important to the extent that few works have combined situational and dispositional factors to explain the smokers’ psychological reactance. The findings in this paper seem interesting insofar as they show the importance of the personality factor and the fear appeal in triggering smokers’ anger and negative cognitions that lead, in turn, to the arousal of psychological reactance. This paper should be of interest to readers in the areas of health communication, social psychology and social marketing.

Solutions of the twin plane jets HF chemical laser flow based on a turbulent kinetic theory, due to a modified Green’s function method, are presented. The calculated results of probability density function (PDF) of various chemical species in velocity space, and mass fraction concentration distributions of various reactants and products in the flow field, are revealed and discussed in this analysis. The transport phenomena of different pumping rate, collisional deactivation rate, and radiative deactivation rate in the interaction between the twin plane jets HF chemical laser show that the properties of species mass fraction concentrations, collisional reaction rate, and radiative incident intensity are the dominant factors. The present study provides the fundamentals for theoretical understanding of twin plane jets HF chemical laser and further application to multiple‐jet HF chemical laser analysis.

The purpose of this paper is to apply the numerical methods to study the heap leaching process in a bed of porous and spherical ore particles. This study is performed in two stages: first, modeling the leaching process of a soluble mineral from a spherical and porous ore particle to obtain the distribution of mineral concentrations, leaching solvent concentration and dissolved mineral in the particles (the particle model), and second, modeling the heap leaching of the mineral from a porous bed consisting of spherical and porous ore particles to obtain the distribution of mineral concentrations, leaching solvent concentration and dissolved mineral in the bed (the bed model).

The governing equations are derived for the particle model, and then converted into non‐dimensional form using reference quantities. The non‐dimensional equations are discretised on a uniform spherical grid fitted to the particle using finite difference method. The resulting algebraic equations are solved using Tri‐Diagonal Matrix Algorithm, and the governing equations are derived for the bed model, and then converted into non‐dimensional form using reference quantities. The non‐dimensional equations are discretised explicitly on a one‐dimensional and uniform grid fitted to the bed. The unknown quantities are evaluated using the corresponding values at the previous time interval.

The results obtained from numerical modeling show that, when the particle has a low diffusion resistance or a high chemical resistance, the reaction takes place slowly and homogeneously throughout the ore particle. On the other hand, when the bed has a low convection resistance, the reaction takes place homogeneously throughout the bed. As the convection resistance increases, the non‐homogeneous (local) behavior predominates. It is also noticed that, when the chemical reaction resistance is high, the reaction takes place homogeneously throughout the bed.

The dynamic diffusion and movement of solution in the ore particles and ore bed are not modeled and volumetric ratio of solution in the particles and the bed and also vertical velocity of solution in the bed are assumed to be fixed constants.

This study shows that the reaction takes place homogeneously throughout the bed when the convection resistance is low, the diffusion resistance is high, the concentration resistance is low, and the chemical reaction resistance is high.

Homogeneous reaction conditions being suitable for heap leaching operations are identified. Thus, it is recommended to approach the above conditions when preparing ore heaps and designing the relevant operation.