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This study aims to observe the coloring efficacy of coffee-based natural brown colorant for cotton dyeing under microwave (MW) treatment.

The colorant extracted in particular (neutral and acidic) media was stimulated by MW treatment up to 6 min. Dyeing variables were optimized and 2–10 g/100 mL of sustainable anchors (mordants) have been used to get colorfast shades.

It has been found that un-irradiated acidic extract (RE) containing 5% of table salt at 80 °C for 50 min has given high color yield onto MW-irradiated cotton fabric (RC = 2 min). The utilization of 2% of Fe, 10% of tannic acid and 10% of sodium potassium tartrate before bio-coloration, whereas 4% of Fe, 10% of tannic acid and 6% of sodium potassium tartrate after bio-coloration has given good color characteristics. In comparison the application of 6% of pomegranate and turmeric extracts before bio-coloration and 6% of pomegranate and 10% of turmeric extracts after bio-coloration have given good color characteristics. New bio-mordants can be added to get more new colorfast shades.

There is no research limitation for this work. New bio-mordants can be added to get more new colorfast shades.

This work has practical application for artisans, textile industry and handicrafts. It is concluded that colorant from coffee beans can be possible alternative of synthetic brown dyes and inclusion of MW rays for extraction and plant molecules as shade developers can make process more green.

Socially, it has good impact on eco-system and global community because the effluent load is not carcinogenic in nature.

The work is original and contains value-added product for textiles and other allied fields.

Drawing from organizational learning theory, social exchange theory and positive psychology approach, this study aims to examine the relationship between commitment to learning and prosocial silence, as well as the mediating role of perceived organizational support (POS) in this relationship.

The authors used path analysis to examine the relationships between research variables. Data were collected from 275 employees of private sector companies in Turkey through an online survey platform. To test the proposed hypotheses, the authors conducted regression and mediation analyses using the bootstrapping method.

The results indicate that the organization’s commitment to learning positively and significantly impacts employee prosocial silence, and POS partially mediates this relationship.

Managers who aim to promote other-oriented and helping behavior in the organization should understand how prosocial silence can be golden. They should cultivate and model a learning mindset by focusing on strengths instead of weaknesses, reward experimentation and provide employees with timely feedback allowing them to think and reflect on their failures.

Although the dominant position of previous studies endorses the detrimental sides of organizational silence, less research has focused on employees’ prosocial silence behavior and the underlying mechanisms that may explain employees’ tendency to remain silent with helpful intent, a gap this research attempts to fill.

The purpose of this paper is to help to understand the influence of the media and political issues in the perceptions of Turkey as a tourism destination. The study is conducted from the perspective of Spanish people.

The research is based on the responses provided to a web survey. The data were analyzed using descriptive statistics and Pearson's correlations.

The views of the Spanish people on the Turkish political situation were not found to be related to the perceptions of the destination, except for those regarding Turkey's candidacy to the European Union. However, an indirect relationship between the political views and the perceptions of the destination through the influence of the former on the image of the host community is proposed. Television and the written press are determined as the most significant information sources, other than word of mouth and experience.

The research points to the fact that political views regarding the country may not affect the perceptions regarding that destination. However, certain political issues seem to have a greater effect on the perceptions of the destination. Therefore, for conclusive evidence a more extensive investigation is required.

The difference between the destination's image and the political views of the country is of practical interest to developing countries, which are dependent on tourism, but generally suffer from political instability and image problems.

The dichotomy between different perceptions regarding a country is investigated. Moreover, the importance of the media in creating perceptions of a destination is analyzed.

The purpose of this paper is to explain the effect of perceived ethical leadership and perceived distributive justice on internal whistleblowing intention through trust in leader as a mediator.

Following an empirical design, data were collected from 1,296 employees of Turkish financial institutions, located in Istanbul. To test four hypotheses structural equation modelling was applied.

Results reveal that trust in a leader fully mediates the positive effects of both ethical leadership and distributive justice on the internal whistleblowing intention.

This study enhances the understanding of the ethical leadership perception and distributive justice affecting the internal whistleblowing intention in Turkey that is a developing country. Although numerous studies on whistleblowing have been conducted, this study’s originality and contribution lay in the examination of trust in the leader as a missing link between the direct relations.

This research aims to explore the potential of big data technology for sustainable management and investigate its impact on tourism. Its goal is to obtain meaningful results related to sustainable tourism to understand better how big data technology plays a role in decision-making by looking at it through the lens of various studies.

A systematic review, which is a qualitative method, was used in this study. The analysis was conducted using secondary data from the Web of Science Core Collections databases.

Big data technology has many economic benefits for businesses, but it also has managerial benefits such as forecasting, decision-making and tracking human and machine behaviour. Furthermore, big data technology offers sustainability benefits such as resource efficiency, preventive quality systems, carbon reduction and environmentally friendly production.

Big data's capabilities enable businesses to make more informed business decisions, improve overall business performance and contribute to achieving various SDGs. Big data, which aids in developing smart and sustainable tourism in the tourism sector, assists tourism managers in making economically, socially and environmentally sound decisions.

Fractional calculus provides powerful tool to build more realistic and accurate mathematical models in economic field. This paper aims to explore a proposed fractional-order differentiated Cournot duopoly game and its discretized game.

Conditions for existence and uniqueness of the proposed game’s solution are derived. The existence of Nash equilibrium point and its local and global stability are obtained. Furthermore, local stability analysis of the discretized game is investigated. The effects of fractional-order on game’s dynamics are examined, along with other parameters of the game, via the 2D bifurcation diagrams in planes of system’s parameters are acquired.

Theoretical and numerical simulation results demonstrate rich variety of interesting dynamical behaviors such as period-doubling and Neimark–Sacker bifurcations, attractors’ crises in addition to chaotic attractors. The results demonstrated that the stability Nash equilibrium point of the game can be lost by period doubling or Neimark–Sacker bifurcations.

Oligopoly games are pivotal in the mathematical modeling of some substantial economic areas such as industrial organization, airline, banking, telecommunication companies, international trade and also macroeconomic analysis of business cycles, innovation and growth.

Although the Cournot game and its variants have attracted great interest among mathematicians and economists since the time of its proposition till present, memory effects in continuous-time and discrete-time Cournot duopoly game have not been addressed yet. To the best of author’s knowledge, this can be considered as the first attempt to investigate this problem of fractional-order differentiated Cournot duopoly game. In addition, studying more realistic models of Cournot oligopoly games plays a pivotal role in the mathematical investigation and better understanding of some substantial economic areas such as industrial organization, airline, banking, telecommunication companies, international trade and also in macroeconomic analysis of business cycles, innovation and growth.

Based on the situational approach for envy, the purpose of this paper is to examine the effect of two-dimensional workplace envy (being envied and envying others) on the task and contextual performance of employees working in either private or public sector organizations.

This study was conducted on survey data collected from 988 private sector employees and 530 employees from the public sector employed in Istanbul. Following a quantitative empirical design, structural equation modeling was used to test the hypotheses.

The study results revealed that envying-others dimension has a significant negative effect on both task performance and contextual performance. In addition, the findings indicate more envious feelings of private sector employees than public sector employees. For public sector employees, male participants were found to envy others more than females.

In addition to the contributions, this study has its limitations. First, although the study was carried out with a comprehensive sample, it is limited to the views of 1,518 employees in Istanbul and is a cross-sectional study. Also, employee performance is evaluated through self-reporting, which forms another limitation; it could have been more reliable for the supervisors to assess their subordinates' performance.

Apart from scholars, our findings have implications for practitioners. Feelings such as envy that comes with a sense of competition can create an environment that stimulates people, motivates them to work, can make them productive and can also cause an ultimately destructive situation. This makes it critical to manage envy in the workplace. Though there may be facilitators behind it, one crucial factor that fuels envy in the workplace is the lack of fair human resources policies and systems. Still, human resources management is undeveloped in most public organizations. With effective human resources management, there may be some roadmaps for managers to dissolve conflicts arising from envy. First, it is imperative to have systems that will separate the employee from the others, which everyone will accept, strengthening the feelings of justice among employees. Envy often occurs following a social comparison. Management can implement an incentive system that supports employee collaboration and avoid nepotism. Especially in private organizations where the competition is more among employees, managers should give more attention to understand their subordinates' feelings. The managers' attention to expressing their feelings toward their subordinates could establish an equal distance within the workplace. In this sense, language selection is critical, and managers should be mindful of linguistic triggers. Managers should not avoid giving both positive and negative feedback to their employees. Unwarranted and unsystematic reward and/or punishment systems, made with the good intentions of increasing competition, can trigger envy. Finally, managers should implement an open-door policy and open communication that will encourage all team members to be transparent to each other.

The study was based on a rationale that envy has detrimental workplace outcomes that lead to low task and contextual performance. Although there exists a recent interest for examining the relation between workplace envy and employee performance, based on being envied and envying others dimensions, these studies are limited. This study focuses on these dimensions and performance relations, and it also provides a comparative outlook for public and private sector employees in Turkey in terms of workplace envy.

The purpose of this study is to prepare a new adsorbent activated carbon immobilized on polystyrene (ACPS) for uranium (VI) and thorium (IV) removal from an aqueous solution. Activated carbon (AC) was derived from biochar material by chemical activation to increase the active sites on its surface and enhance the adsorption capacity. Activated carbon (AC) was immobilized on polystyrene (PS) to improve the physical properties and facilitate separation from the working solution. A feasibility study for the adsorption of uranium (VI) and thorium (IV) on the new adsorbent (ACPS) has been achieved. Adsorption kinetics, isotherms, and thermodynamics models of the adsorption process were used to describe the reaction mechanism.

Activated carbon was synthesized from biochar charcoal by 2 M H₂SO₄. Activated carbon was immobilized on the pretreatment polystyrene by hydrothermal process forming new adsorbent (ACPS). Characterization studies were carried out by scanning electron microscope, energy-dispersive X-ray spectrometer, infrared spectroscopy and X-ray diffraction techniques. Different factors affect the adsorption process as pH, contact time, solid/liquid ratio, initial concentration and temperature. The adsorption mechanism was explained according to kinetic, isothermal and thermodynamic studies. Also, the regeneration of spent ACPS was studied.

The experimental results showed that pH and equilibrium time of the best adsorption were 6.0 and 60 min for U(VI), 4.0 and 90 min for Th(IV), (pH_PZC = 3.4). The experimental results fit well with pseudo-second order, Freundlich and Dubinin–Radushkevich models proving the chemisorption and heterogenous adsorption reaction. Adsorption thermodynamics demonstrated that the adsorption process is exothermic and has random nature of the solid/liquid interface. In addition, the regeneration of spent ACPS research showed that the adsorbent has good chemical stability. According to the comparative study, ACPS shows higher adsorption capacities of U(VI) and Th(IV) than other previous bio-adsorbents.

This study was conducted to improve the chemical and physical properties of bio-charcoal purchased from the local market to activated carbon by hydrothermal method. Activated carbon was immobilized on polystyrene forming new adsorbent ACPS for eliminating U(VI) and Th(IV) from aqueous solutions.