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This study aims to investigate the cross-sectional reshaping in transitioning/starting rectangular jets of aspect ratio 2 under various inlet perturbation conditions at the Reynolds number of Re = UD_h/v = 17,750.

Large eddy simulation results compared with the phase-locked particle image velocimetry data exhibit the cross-sectional jet deformations from rectangular to rounder shapes. Inflow velocity oscillations are introduced at the fundamental frequency associated with the Kelvin–Helmholtz instability characterized by the spectral analysis of the hotwire data and the linear stability predictions.

The initially rectangular cross-section of the jet reshapes into the rounder geometries with increased downstream distance while the edges of the jet become distorted due to the shear layer instability more significantly observed near the high curvature corners. The different expansion rates in the longer and shorter edges of the jet and the consequent cross-sectional reshaping are found to be sensitive to small levels of random inlet perturbations. In addition, introducing controlled sinusoidal oscillations results in the formation of more organized trailing shear layer where the stronger vortex rings go through the curvature-induced deformations.

Spatio-temporal study of vortex dynamics in transitioning rectangular jets reveals important information about the effect of the controlled jet forcing on local entrainment. Dynamics of the leading vortex dominates the entrainment in transitioning jets which are commonly used in practical applications. Near-field entrainment is also promoted proportional to the amplitude of the controlled inlet oscillations within the trailing vortex rings.

Consumer expectations of quality have grown in recent years, forcing organisations, both service and manufacturing, to adopt total quality management (TQM) principles to satisfy customer demands efficiently. However, previous studies on the performance impacts of total quality management practices have mainly focused on the financial performance of firms in the manufacturing sector. This study focusses on the research questions: (1) What is the effect of TQM practices on operational performance? and (2) How do TQM practices combine to influence the operational performance of healthcare facilities?

Using a sample of 154 health facilities (i.e. private hospitals, pharmacies, maternity clinics, and diagnostic centres), the authors applied symmetric (PLS-SEM) and asymmetric (fsQCA) data analysis approaches to examine how TQM practices influence the operational performance of health facilities in the Ashanti Region of Ghana.

The PLS-SEM results revealed that five out of the seven TQM practices investigated influenced operational performance. However, the fsQCA results identify five different complex combinations of TQM practices that lead to operational performance.

Longitudinal studies can be conducted in the future to assess changes in the variables over time. A control variable, such as firm size, should be considered to assess the level of implementation of TQM practices based on firm size. A different performance measure, for instance, sustainability indicators or the balance score card, could be used to examine performance.

A proper and coordinated integration of the TQM practices is required for firms to be able to achieve operational performance. TQM practices vary in their sufficiency for operational outcomes; therefore, management needs to carefully consider their implementation as part of the organisation's strategy.

This research, by focussing on TQM practices from both symmetrical and asymmetrical perspectives, contributes to the understanding of the literature on TQM, thereby providing actionable insight on how to invest in the various TQM practices for improved operational performance.

This study aims to investigate the application of Web 2.0 technologies in the libraries of the top 100 universities in the world to provide a model for Web 2.0 application in academic library websites.

Data were collected from the universities’ library websites for three months based on a Web 2.0 checklist. The list of universities was extracted from Webometrics Ranking of World Universities in 2015.

The research shows the priorities of these universities in their use of Web 2.0 tools include social networks and mashups at the most (94.5 per cent), followed by RSS (91.2 per cent) and social tagging (82.4 per cent) and other tools with lower priorities. Moreover, it revealed the most common applications of these tools in the mentioned websites followed by their objective evidences in different libraries. The results indicate that the total Web 2.0 application in the libraries of the top 100 universities was below average (40.23 per cent). Finally, the model for Web 2.0 application in academic library websites was designed.

The focus of this study is on the value and application of each tool in the websites and demonstrate a clear model to apply in other library websites. The model for Web 2.0 technologies application in academic library websites has not been designed and pictured before.

The purpose of this paper is to carry out a comprehensive review of some latest studies devoted to natural convection phenomenon in the enclosures because of its significant industrial applications.

Geometries of the enclosures have considerable influences on the heat transfer which will be important in energy consumption. The most useful geometries in engineering fields are treated in this literature, and their effects on the fluid flow and heat transfer are presented.

A great variety of geometries included with different physical and thermal boundary conditions, heat sources and fluid/nanofluid media are analyzed. Moreover, the results of different types of methods including experimental, analytical and numerical are obtained. Different natures of natural convection phenomenon including laminar, steady-state and transient, turbulent are covered. Overall, the present review enhances the insight of researchers into choosing the best geometry for thermal process.

A comprehensive review on the most practical geometries in the industrial application is performed.

Plant materials continue to play a major role in primary health care as therapeutic remedies in many developing countries. Medicinal herbs contain physiologically active principles that over the years have been exploited in traditional medicine for the treatment of various ailments as they contain antimicrobial properties. This paper aims to determine the antibacterial activity of Iranian endemic plants.

Antibacterial activities of ethanol extract and essential oil of ten Iranian folklore herbs including Heracleum lasiopetalum Boiss., Hypericum scabrum L., Thymus daenensis Celak., Ziziphora teniur L., Echiophora platyloba L., Dracocephalum multicaule Benth., Kelussia odoratissima Mozff., Mentha longifolia Hudson., Achillea kellalensis Boiss. and Arnebia euchroma (Royle.) Johnston. were investigated against Yersinia enterocolitica PTCC 1151 by agar disc diffusion and serial dilution assays.

Most of the extracts and essential oils showed some antibacterial activity against the tested bacteria with the diameter of inhibition zone ranging between 9 and 16 mm. Of the plants studied, the most active extracts were those obtained from essential oil of H. lasiopetalum fruits and ethanol extract of A. euchroma roots. The MIC values for active extract and essential oil ranged between 0.039 and 0.156 mg/ml.

The results obtained appeared to confirm the antibacterial potential of the plants investigated.

The essential oil <0.039 mg/ml of H. lasiopetalum fruits could be used as natural antibacterial agent Y. enterocolitica in the food preservation and human health.

This study aims at investigating the impact of total quality management (TQM) on corporate sustainability (CS) by mediating the role of corporate social responsibility (CSR) in developing countries.

A mixed research approach was adopted by conducting interviews and a survey. A survey was used as a quantitative tool for data collection from 67 respondents at different managerial levels. Partial least squares structural equation modeling (PLS-SEM) was used for analysis.

The findings demonstrate that customer focus and human resource management (HRM) were the most effective practices. Structural analysis revealed that TQM had a significant impact on CSR and CS. Furthermore, CSR partially mediates the relationship between TQM and CS.

The study has developed a conceptual framework to provide policymakers with guidelines on integrating TQM practices and CSR activities into their strategy.

This research bridges the gap between TQM and the three pillars of CS, especially in manufacturing enterprises in a developing country context. This research also supports the TQM advocate's argument that effective TQM deployment can dramatically improve organizational performance. Additionally, this study verifies the CS model based on the triple bottom line (TBL) theory and stakeholder theory by assessing the conceptual model's robustness using a mixed-method research methodology, which has never been done before from a Palestinian perspective.

Children have the ability to contribute to sustainable tourism research. A great deal of research on nature holiday has been conducted. However, it is unclear how this travel might serve as a good motivator for children to engage in environmentally responsible behaviour. To address this research gap, 72 drawings of children aged nine to 12 from Tehran, Iran, accompanied with the stories of their holiday were collected. Thematic analysis was done to assess their experience in nature and their cognitive state of environmental responsible behaviour. According to the finding, children are significantly concerned about nature, and they mostly perceived their best holidays in the natural environment. Children displayed a profound awareness of environmental responsible behaviour themes through their encounters with nature. Their experiences are classified into five levels: sensory, emotive, cognitive, behavioural and relationship. Each of these stages of experience may be used as a guideline for encouraging and training youngsters to be responsible.

The present study aims at quantifying the likely impacts of an environmental tax on macroeconomic variables and pollution in Iran.

The computable general equilibrium model, which allows the prediction of the economy-wide effects of any change in policy instruments, is applied.

The main findings reveal that gross domestic product, private consumption and income in both urban and rural areas will follow a declining trend as a result of environmental tax imposition. In a scenario with the highest level of tax, the predicted percentage change to the gross domestic product and private consumption is estimated at −21.32 and −40.96, respectively. In the same scenario, pollution emissions would decrease by 12.4–22.6% for CO2, CH4 and N2O.

This study uses a general equilibrium model to examine the effects of the carbon tax on environmental issues and household welfare, considering the unique conditions and regulations of Iran. While the related literature examines the CO2 tax, the current study covers more pollutants, including CO2, CH4, N2O, CO, SO2 and NOx. In addition, a distinguishing feature of the current study is that it applies a modified version of the social accounting matrix (SAM) database, which includes the heavy subsidies of energy products. Another significant feature of the current study is that it examines tax policy while tax rates are exerted endogenously (compared to previous studies).

This study aims to investigate the three-dimensional natural convection and entropy generation in a cuboid enclosure filled with CuO-water nanofluid.

The lattice Boltzmann method is used to solve the problem numerically. Two different multiple relaxation time (MRT) models are used to solve the problem. The D3Q7–MRT model is used to solve the temperature field, and the D3Q19 is used to solve the fluid flow of natural convection within the enclosure.

The influences of different Rayleigh numbers (10³ < Ra < 10⁶) and solid volume fractions (0 < f < 0.04) on the fluid flow, heat transfer, total entropy generation, local heat transfer irreversibility and local fluid friction irreversibility are presented comprehensively. To predict thermo–physical properties, dynamic viscosity and thermal conductivity, of CuO–water nanofluid, the Koo–Kleinstreuer–Li (KKL) model is applied to consider the effect of Brownian motion on nanofluid properties.

The originality of this work is to analyze the three-dimensional natural convection and entropy generation using a new numerical approach of dual-MRT-based lattice Boltzmann method.