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The purpose of this study is to assess the performance of ANSYS Fluent^® and OpenFOAM^®, at their current state of development, to study the relevant bubbling fluidized bed (BFB) characteristics with Geldart A, B and D particles.

For typical Geldart B and D particles, both a three-dimensional cylindrical and a pseudo-two-dimensional arrangement were used to measure the bed pressure drop and solids volume fraction, the latter by digital image analysis techniques. For a typical Geldart A particle, specifically to examine bubbling and slugging phenomena, a 2 m high three-dimensional cylindrical arrangement of small internal diameter was used. The hydrodynamics of the experimentally investigated BFB cases were also simulated for identical geometries and operating conditions using OpenFOAM^® v6.0 and ANSYS Fluent^® v19.2 at identical mesh and numerical setups.

The comparison between experimental and simulated results showed that both ANSYS Fluent^® and OpenFOAM^® provide a fair qualitative prediction of the bubble sizes and solids fraction for freely-bubbling Geldart B and D particles. For Geldart A particles, operated in a slugging mode, the qualitative predictions are again quite fair, but numerical values of relevant slug characteristics (length, velocity and frequency) slightly favor the use of OpenFOAM^®, despite some deviations of predicted slug velocities.

A useful comparison of computational fluid dynamics (CFD) software performance for different fluidized regimes is presented. The results are discussed and recommendations are formulated for the selection of the CFD software and models involved.

Excess sludge is an inevitable drawback of the waste‐activated sludge process. Both the reduction of the amount of sludge produced and improving its dewaterability are of paramount importance. With more stringent environmental and legislative constraints, increasing sludge production and limited disposal options, new reduction alternatives have to be found. This paper presents different advanced sludge treatment (AST) processes, i.e. thermal hydrolysis (neutral, acid, alkaline) and chemical oxidation using H₂O₂. Semi‐pilot and pilot‐scale experiments are conducted in order to achieve optimum treatment conditions (T, pH, concentration of reagent, catalyst, etc.) with respect to sludge dewaterability. Additional targets are the removal of heavy metals and pathogens from the sludge so that the residual filter cake can be used for land application. Although all methods are promising, peroxidation gave the best results with respect to improving sludge dewaterability and product quality of the residual filter cake. The amount of dry solids per equivalent‐inhabitant per day (DS/IE.d) was reduced from 60g DS/IE.d to 33g DS/IE.d and the percentage DS of the sludge cake was 47 per cent, which is a significant improvement of traditional sludge dewatering yields. This results in a significantly reduced energy for subsequent drying (94kJ/IE.d compared to 437kJ/IE.d for the traditional treatment).

Silver has been known to mankind from time immemorial. It was one of the prized possessions of kings and nobles. From earliest times, it has been known for its intimate association with (i) monetary system, (ii) use as a silverware for household purposes and (iii) beauty and elegance when shaped into ornaments. Now, an increased understanding of the properties of silver results in its application in the rapidly developing technologies, namely communications, electronics, space explorations, etc.

The purpose of this paper is to extend the h-index framework to the case that articles are counted fractionally.

Three restrictions related to the standard h-index are explained: as the standard h-index is a natural number it is a rather coarse indicator; if a scientist has published a relatively small number of publications then the h-index is completely determined by the number of publications; the standard h-index cannot be applied if publications are counted fractionally, or when magnitude values smaller than one occur.

We recall solutions we proposed in earlier publications regarding the first two problems (the use of the interpolated h-index and of the pseudo h-index) and add a new proposal to solve the third problem. The relation between the recently introduced window/field-normalized h-type index (hwf-index) and the interpolated h-index is described. A real-world example proves the feasibility of this proposal.

Colleagues have shown that the h-index and its variations have fatal flaws and hence should never be used. Yet, not everyone agrees with this opinion.

Assuming that the h-index still has some value, this paper introduces a refinement of the interpolated h-index, called the generalized interpolated h-index. In this way the h-index framework is extended to incorporate, for instance, the case that fractional counting for publications and citations is applied.

This study explored Croatian nursing students' knowledge and attitudes regarding brominated flame retardants (BFRs) as indicators of their predisposition to educate future patients. The purpose of the study was to identify knowledge gaps and barriers and to propose possible remedies.

The cross-sectional survey was conducted on a convenience sample of 114 nursing students at undergraduate and graduate levels from three Croatian universities during the winter semester in the academic year 2018–2019. Descriptive and inferential statistical  analyses were performed using STATISTICA 13 software.

Slightly over half of the students (58.49%) were knowledgeable of BFR health effects and 45.28% showed knowledge about its presence in the environment. Only 33.02% of students identified prenatal exposure effects and 24.53% answered correctly about legislative actions. Participants expressed modest interest in the topic (M = 3.15, SD = 1.35). Although informing the public on the health consequences of BFRs was important to them (M = 4.18, SD = 1.03), they did not perceive health-care providers as primarily responsible for communicating that information.

There is a need to enhance related content in the curriculum to improve students' knowledge. Raising students' awareness regarding the role of nurses in clinical and policy arenas is proposed to facilitate active participation in improving environmental health.

Users' voluntary forwarding behavior opens a new avenue for companies to promote their brands and products on social networking sites (SNS). However, research on voluntary information disseminators is limited. This paper aims to bring an in-depth understanding of voluntary disseminators by answering the following questions: (1) What is the underlying mechanism by which some users are more enthusiastic to voluntarily forward content of interest? (2) How to identify them? We propose a theoretical model based on the Elaboration-Likelihood Model (ELM) and examine three types of factors that moderate the effect of preference matching on individual forwarding behavior, including personal characteristics, tweet characteristics and sender–receiver relationships.

Via Twitter API, we randomly crawled 1967 Twitter users' data to validate the conceptual framework. Each user’s original tweets and retweeted tweets, profile data such as the number of followers and followees and verification status were obtained. The final corpus contains 163,554 data points composed of 1,634 valid twitterers' retweeting behavior. Tweets produced by these core users' followees were also crawled. These data points constitute an unbalanced panel data and we employ different models — fixed-effects, random-effects and pooled logit models — to test the moderation effects. The robustness test shows consistency among these different models.

Preference matching significantly affects users' forwarding behavior, implying that SNS users are more likely to share contents that align with their preferences. In addition, we find that popular users with lots of followers, heavy SNS users who author tweets or forward other-sourced tweets more frequently and users who tend to produce longer original contents are more enthusiastic to disseminate contents of interest. Furthermore, interaction strength has a positive moderating effect on the relationship between preference matching and individuals' forwarding decisions, suggesting that users are more likely to disseminate content of interest when it comes from strong ties. However, the moderating effect of perceived affinity is significantly negative, indicating that an online community of individuals with many common friends is not an ideal place to engage individuals in sharing information.

This work brings about a deep understanding of users' voluntary forwarding behavior of content of interest. To the best of our knowledge, the current study is the first to examine (1) the underlying mechanism by which some users are more likely to voluntarily forward content of interest; and (2) how to identify these potential voluntary disseminators. By extending the ELM, we examine the moderating effect of tweet characteristics, sender–receiver relationships as well as personal characteristics. Our research findings provide practical guidelines for enterprises and government institutions to choose voluntary endorsers when trying to engage individuals in information dissemination on SNS.

This paper aims to overview the need for tobacco harm reduction, the consumer products that facilitate tobacco harm reduction and the barriers to its implementation. The worldwide endemic of tobacco smoking results in the death of over seven million smokers a year. Cigarette quit rates are very low, from 3%–12%, and relapse rates are high, from 75%–80% in the first six months and 30%–40% even after one year of abstinence. In addition, some smokers do not desire to quit. Cigarette substitution in tobacco harm reduction is one strategy that may reduce the burden of morbidity and mortality.

This review examines the displacement of smoking through substitution of non-combustible low-risk products such as snus, heated tobacco products and e-cigarettes.

Toxicological testing, population studies, clinical trials and randomized controlled trials demonstrate the potential reductions in exposures for smokers. Many barriers impede the implementation of product substitution in tobacco harm reduction. These products have been subjected to regulatory bans and heavy taxation and are rejected by smokers and society based on misperceptions about nicotine, sensational media headlines and unsubstantiated fears of youth addiction. These barriers will need to be addressed if tobacco harm reduction is to make the maximum impact on the tobacco endemic.

This review provides the rationale for tobacco harm reduction, evaluates the current products available and identifies the barriers to implementation.