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A review of sustainability challenges of flame retardants (FRs) for textiles has been conducted. Specifically, the purpose of this paper is to identify and recommend solutions to sustainability challenges emanating from the raw material, processing technology and performance of the FRs used for textiles.

The approach used in preparing this paper was based on the review of various scholarly databases about the subject matter. The review approach is designed to inform the readers about the sustainability challenges of FRs for textiles. The science of burning and FRs for synthetic and cellulosic fibres were reviewed. Both synthetic and natural biodegradable FRs for textiles has been identified. The obtained literature was then synthesised to get information about sustainable challenges of non-halogenated FRs both synthetic and natural biodegradable. Finally, possible approaches for mitigating the identified challenges have been recommended.

The sustainability challenges of the FRs in terms of raw material, processing, affordability and performance have been identified. Synthetic FRs suffer from sustainability challenges in terms of raw materials, processing and non-renewability. Despite the environmental friendliness and sustainability in terms of being renewability, processability and biodegradability, natural biodegradable FRs have poor performance compared to synthetic ones. Moreover, natural biodegradable FRs depend on geographical condition and lack economic variability data. Potentially, the challenges of FRs can be mitigated through eco-friendly synthesis, chemical modification and sustainable methods of applications. Because of its renewability and environmental friendliness, biodegradable FRs have a potential to becoming sustainable if researched more.

In this review, a collection of literature about sustainability challenges of FRs and the approaches to overcome the challenges has been provided. The collected information was analysed and synthesised to bring understanding of the science of burning, types and application of FRs for textiles and biodegradable FRs. Sustainability challenges have been identified, and mitigation approaches are provided.

This study aims to synthesize two different benzoxazines (Bz) monomers using bio-based and petroleum-based primary amines, respectively, and they have been compared to study their thermal and mechanical performances.

A bio-based bisphenol, Divanillin (DiVa), was formed by reacting two moles of vanillin with one mole of ethylenediamine (EDA) which was then reacted firstly with paraformaldehyde and EDA to form the benzoxazine DiVa-EDA-Bz, and secondly with paraformaldehyde and furfuryl amine (FFA) to form the benzoxazine DiVa-FFA-Bz. The molecular structure and thermal properties of the benzoxazines were characterized by fourier transform infrared spectroscopy and nuclear magnetic resonance (1H,13C) spectroscopies, differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), respectively. The benzoxazines were further coated on mild steel panels to evaluate their mechanical properties and chemical resistance.

The DSC results of DiVa-FFA-Bz showed two exothermic peaks related to crosslinking compared to the one in DiVa-EDA-Bz. The DiVa-FFA-Bz also showed a higher heat of polymerization than DiVa-EDA-Bz. The TGA results showed that DiVa-FFA-Bz exhibited higher thermal stability with a residual char of 54.10% than 43.24% for DiVa-EDA-Bz. The chemical resistance test results showed that DiVa-FFA-Bz showed better chemical resistance and mechanical properties due to its higher crosslinking density.

This study shows the use of bio-based materials, vanillin and FFA, for synthesizing a benzoxazine resin and its application at high temperatures.

This study aims to develop multifunctional, namely, superhydrophobic, flame-retardant and antibacterial, coatings over cotton fabric, using casein as green-based flame-retardant and silver nanoparticles as antibacterial agent by solution immersion method.

The cotton fabric is first coated with casein to make it flame-retardant. AgNPs synthesized using Cinnamomum zeylanicum bark extract is coated over the casein layer. Finally, stearic acid is used to coat the cotton to make it superhydrophobic. X-ray diffraction, transmission electron microscopy analysis and ultraviolet-visible spectroscopy are used to investigate the produced AgNPs. The as-prepared multifunctional cotton is characterized by scanning electron microscopy, energy dispersive X-ray analysis and attenuated total reflection-infrared studies. Flame test, limiting oxygen index test and thermogravimetric analyzer studies have also been performed to study the flame-retardant ability and thermal stability of treated fabric, respectively. The antibacterial effect of the coatings is evaluated by disc-diffusion technique. Water contact angle is determined to confirm the superhydrophobic nature of cotton fabric.

The outcomes of this study showed that the prepared multifunctional cotton fabric had maximum contact angle of greater than 150° with good flame retardancy, high thermal stability, greater washing durability and high antibacterial activity against the growth of Pseudomonas aeruginosa and Acinetobacter indicus. Additionally, the as-prepared superhydrophobic cotton showed an excellent oil–water separation efficiency.

The trilayered multifunctional cotton fabric has limiting washing durability up to 20 washing cycles. Treated functional fabric can be used as an antibacterial, therapeutic, water repellent and experimental protective clothing for medical, health care, home curtains and industrial and laboratory purposes.

The study brings out the robustness of this method in the development of multifunctional cotton fabrics.

This study aims to examine the relationship between CEO characteristics and the value of excess cash holdings from the perspective of resource-based view (RBV) theory in the context of Malaysia.

The analyses were made using ordinary least squares across 173 non-financial firms listed in Bursa Malaysia over the period of 2015–2021. The authors address potential endogeneity through the generalized method of moments. The results are also robust to alternative measures of excess cash holdings.

The results showed that female CEOs and CEOs’ educational level are significantly positively related to the value of excess cash holdings. In contrast, CEO tenure and CEO age negatively affect a firm’s excess cash valuation. The results are robust to measurement error and endogeneity issues.

The empirical results have useful policy implications. For practitioners, firms are recommended to prioritize the selection of female CEOs and CEOs with high education levels within their top management, as this initiative can result in improved value associated with excess cash holdings. In addition, policymakers are recommended to guide programs that attempt to improve educational attainment and gender diversity in business leadership. This study also provides investors with insightful information about the possible relationship between CEO traits and company performance, especially with regard to measures for managing surplus capital.

To the best of the authors’ knowledge, this study is the first to explore the role of CEO characteristics in the value of excess cash holdings based on the RBV theory.

This paper aims to analyze the performance of artificial neural networks with filling methods in predicting the minimum fluidization velocity of different biomass types for bioenergy applications.

An extensive literature review was performed to create an efficient database for training purposes. The database consisted of experimental values of the minimum fluidization velocity, physical properties of the biomass particles (density, size and sphericity) and characteristics of the fluidization (monocomponent experiments or binary mixture). The neural models developed were divided into eight different cases, in which the main difference between them was the filling method type (K-nearest neighbors [KNN] or linear interpolation) and the number of input neurons. The results of the neural models were compared to the classical correlations proposed by the literature and empirical equations derived from multiple regression analysis.

The performance of a given filling method depended on the characteristics and size of the database. The KNN method was superior for lower available data for training and specific fluidization experiments, like monocomponent or binary mixture. The linear interpolation method was superior for a wider and larger database, including monocomponent and binary mixture. The performance of the neural model was comparable with the predictions of the most well-known correlations from the literature.

Techniques of machine learning, such as filling methods, were used to improve the performance of the neural models. Besides the typical comparisons with conventional correlations, comparisons with three main equations derived from multiple regression analysis were reported and discussed.

No Olympics in recent history have come in on or under budget, with past Olympics having overrun their budgets by an average of 172% (Flyvbjerg et al., 2021). Growing concerns among taxpayers about the expense have led many cities to drop out of the bidding process for the Olympics: for the 2024 Olympic Games, bids were withdrawn by Boston, Budapest, Hamburg, and Rome (Okada & Greyser, 2018). Sports infrastructure, including the main stadium, is a major cost category for the Olympic Games. Building or renovating venues to Olympic specifications can leave cities with heavy costs of long-term maintenance as well as the cost of initial construction (Baade & Matheson, 2016). In practice, cities tend to overestimate the size and suitability of existing venues, leading to underestimated costs and budget overruns (Preuß et al., 2019). The Brisbane 2032 Olympic bid says that Brisbane’s Olympics are confident of breaking even, and avoiding building stadiums that end up as white elephants. But does the choice of Olympic stadium make a difference to the final cost overrun? This study finds that cost overruns for past Olympics have been predicted using a few characteristics of the main stadium: its age, its distance from the city centre, and its seating capacity. This has important policy implications for selecting stadiums to be used at the Olympic Games and particularly for the Brisbane 2032 Olympic Games where a stadium has been earmarked for selection without data-driven evidence to support the decision.

For the sake of sustainable development and environmental preservation, it is crucial to develop UV-curable coatings composed of renewable resources. Castor oil, being both bio-based and economical, serves as the focal point of this research paper. The purpose of this research paper is to synthesize, formulate and apply a UV-curable biobased oligomer ECOSAGMA as a wood coating, with a focus on sustainable development and environmental preservation. Castor oil, being both bio-based and economical, serves as the focal point of this research paper.

ECOSAGMA was prepared by reacting epoxidized castor oil with sebacic acid, followed by reaction with glycidyl methacrylate through ring opening reaction. The chemical structure of ECOSAGMA was confirmed by Fourier-Transform infrared spectroscopy, 13C-NMR and 1H-NMR spectroscopy. The synthesized oligomer was used for UV-curable coating formulations by combining it with varying amounts of TMPTA from 10 to 40 wt.% and studied for their rheological properties. The UV curable formulations were co-photopolymerized into thin coatings and were thoroughly examined based on thermal, chemical and mechanical properties.

The UV-cured coating containing ECOSAGMA and TMPTA exhibits exceptional mechanical, chemical and thermal properties, underscoring their potential for deployment in real-world application. It is observed that an increase in the concentration of TMPTA is associated with a notable enhancement in the properties of the UV-cured coatings. The UV-cured wood coating, composed of 40 wt.% TMPTA, demonstrates remarkable stain resistance properties.

In conclusion, by embracing eco-friendly and economically conscious principles., it is evident that this synthesized novel castor oil-based oligomer offers a range of valuable properties to the coating such as stain resistance and thermal stability as well as characteristics such as gloss, hardness, adhesion and chemical resistance.

“Immediate Gratuitousness” puts cryptocurrency and its sister industries into a history of performances of extravagance, daring, and waste. My assertion is that the people to read at this point in the development of crypto are not Mazzucato or Galbraith, Minsky or Perez (or Hayek and Mises), but Antonin Artaud, playwright of the theater of self-destruction and gratuitous gestures. This account of crypto situates it in a context of value produced through performance and ruinous waste, from burning a million British pounds on the Isle of Jura in 1994 to the production of proof-of-burn minting mechanisms, and explains how to make sense of our carnivalesque moment through the logic of the extravagantly destructive.

This study investigates the service quality dimensions of hotel resorts in renowned beach destinations of Thailand. It also explores the relationship between review text sentiment expressed in online platforms and the satisfaction ratings provided for those reviews.

The study employs a two-step analysis approach: first, supervised and unsupervised machine learning via support vector machine (SVM) and latent Dirichlet allocation (LDA) are used to identify service quality dimensions, and second, SmartPLS with PROCESS macro is applied to analyze the moderating roles of quality signals and reviewer’s experience on the relationship between sentiment and satisfaction rating. The dataset comprises 102,179 online reviews from TripAdvisor, focusing on 187 selected hotels rated from 3 to 5 stars.

Eight service quality dimensions were identified, including leisure activities, tangibles and surroundings, reliability, responsiveness, service process, food, empathy and ambience. The study underscores that the service process stands as the sole dimension exhibiting negative sentiment. Furthermore, the analysis revealed a robust positive association between sentiment of review texts and satisfaction, and reviewers’ experience and brand affiliation influenced the relationship between customer sentiment and satisfaction.

Hotel managers should focus efforts on maintaining tangible aspects while enhancing existing service quality level of other dimensions, particularly those related to intangible elements. Independent hotels might implement quality audit to ensure that service quality gaps are monitored.

This study contributes an examination of the moderating roles of quality signals and reviewer’s experience on the relationship between review sentiment and satisfaction rating in online reviews.