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The purpose of this study is to prepare Polystyrene grafted with Zeolite Y (Zeosty) for Uranyl ion [U(VI)] adsorption from aqueous solution. The adsorption mechanism has been explained by studying kinetic, isothermal and thermodynamic models.

Polystyrene was grafted with Zeosty by a simple hydrothermal technique. Zeosty was characterized by different techniques such as X-ray diffraction, scanning electron microscope, energy dispersive X-ray and Infrared spectroscopy to confirm its structure and its molecular composition. Zeosty was used for U(VI) adsorption from an aqueous solution in a series of batch experiments. The effects of pH, contact time, initial U(VI) concentration and temperature on the adsorption process were investigated.

The results showed that the adsorption of U(VI) on the prepared reached equilibrium at pH 6 with a removal efficiency of 98.9%. Adsorption kinetics and isotherms models are studied on the experimental data to estimate the mechanism of the adsorption reaction was chemisorption and homogenous reaction. The activity of Zeosty increased at high temperatures, resulting in the adsorption capacity increase. Thermodynamic parameters ΔGo, ΔHo and ΔSo indicate that the adsorption processes are spontaneous and endothermic. Zeosty has an effective surface and could be considered a valuable adsorbent for U(VI) removal from aqueous waste. A comparison study proves that the new adsorbent has high effective behavior in the adsorption process, and it is considered a new reliable adsorbent for U(VI) removal from wastewater.

This study is complementary to the previous study using the same technique to prove that the effective fine particle adsorbents need solid support to enhance their absorption capacities.

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.

The purpose of this paper is to demonstrate a successful fabrication of 2 × 128 linear array of typical infrared (IR) detectors made of p-type tSi/porous Si Schottky barrier.

Using metal-assisted chemical etching (MaCE) as a unique approach, a sample definition of a porous Si nanostructure region for fabricating of any high-density photodetectors array has been formulated. Besides, the uniformity of pixels at different position along the array has been confirmed by optical images and measurements of photocurrent in IR regime at room temperature.

The experimental result illustrates the existence of an open-circuit voltage up to 30 mV at 1.5-μm wavelength for an area of 50 × 50 μm2. Additionally, this behavior is almost the same at different pixels of fabricated array.

The uniformity of pixels and definition of nanostructure region are two most important challenges in fabrication of any high-density photodetectors array.

MaCE guarantees formation of reproducible, high-fidelity and controllable nanometer-size porous Si with well-defined and sharp edges of the patterned areas.

The proposed method offers a low-cost and simple process to fabricate high-density arrays of Schottky detectors which are compatible with the complementary metal-oxide semiconductor process.

Food scandals and reports of food withdrawals from the market could be caused by a lack of internal reporting and speaking up about non-compliances. The aim of this paper is to examine and explain the concept of just culture (JC) and to explain the essence of other subcultures, including the culture of voice (whistleblowing), which can more effectively support the reporting of food safety (FS) incidents and, above all, enhance an overall food safety culture (FSC).

Parallels are drawn between the use of the term “just culture” and of reporting of non-compliances as a decisive factor in avoiding FS incidents. The evolution of the term is developed via the literature on JC from other high-risk sectors, particularly healthcare.

The concept of JC and its meaning in the food sector was explained. Many parallels from the healthcare have been identified and explained with regard to the reporting on FS incidents. The definitions of JC in the food sector, of whistleblowing and whistleblower were proposed. Classification of FS incidents allowing for their more effective monitoring and reporting, as well as a reporting verification matrix (RVM), has been developed.

There is still little work on the necessity and the organizational conditions conducive to FS incident reporting. JC in the food sector is completely unknown and requires wide dissemination among scientists and practitioners. This paper will be of great interest to industry, academics and public health officials and can be used as a platform for discussions and activities aimed at implementing JC in the food sector.

The purpose of this paper is to determine the required physical and social attributes of open spaces and demonstrate the effects of these attributes on place dependency, which is the functional dimension of place attachment. In this context, the paper only focused on the effects of the physical and social attributes of the environment on the place attachment.

The general framework of the study design included the determination of the place attachment value for the space through identification of its physical and social attributes by the users. The research method included the evaluation of the physical and social attributes and the place attachment.

The study model demonstrated that the place attachment increased in successful urban spaces where user needs are met at a higher level. It was demonstrated that the social attributes, in particular the social environment, had a higher impact on the functional attachment of the users when compared to the physical attributes.

The present study investigated the factors that affected place attachment in urban open spaces within the context of human–environment interaction and specifically in the context of Trabzon square parks.

The study findings are considered important for both urban planners and administrators, who are responsible for protection and development of urban spaces, and the users.

The present study attempted to investigate the effects of physical and social attributes of the place on place dependence.

While the COVID-19 pandemic has impacted the construction industry, it is still unclear from prior studies about adequately positioning the quality assurance (QA) for the post-pandemic era and future pandemics, especially cross-border construction logistics and supply chain (Cb-CLSC). Thus, this study aims to develop a managerial framework to position the QA of Cb-CLSC during pandemics and post-pandemics by taking lessons from how COVID-19 has impacted the existing QA systems and has been managed successfully.

This is achieved pragmatically through an embedded mixed-method design involving a literature review, survey and interview from experts within the Hong Kong SAR–Mainland China links, typically known as the world’s factory. The design is further integrated with the partial least squares structural equation modelling (PLS-SEM) approach.

The study revealed 10 critical managerial practices (MPs) to position the QA to be adequate for the post-pandemic and during future pandemics, with the top three including “strict observance of government regulations (MP1)”, “planning ahead the period of quality assurance with the quarantine days in host countries (MP6)” and “modification of contract to cater for uncertainties (MP4)”. This attained a relatively good percentage agreement of 53% between the industry and academia. However, the top four MPs regarded as very effective include “implementing digital collaborative inspections with subcontractors and trades (MP8)”, “implementing a digital centralized document and issue management system (MP7)”, “strict observance to government regulations, including vaccination of workers, social distancing, use of prescribed nose masks, etc. (MP1)” and “planning ahead the period of quality assurance with the quarantine days in host countries (MP6)”. Two underlying components of the MPs were revealed as policy-process (PP)-related practices and people-technology-process (PTP)-related practices, and these can be modelled into a managerial framework capable of effectively positioning the QA to be adequate during pandemics through to the post-pandemic era.

The findings of this study depicted significant theoretical and practical contributions to the proactive management of QA activities during pandemics through to the post-pandemic era. It could empower organisations to pay attention to smartly and innovatively balancing people, processes, pandemic policy and technology to inform decisions to effectively position the QA for the post-pandemic era and survive the risks of future pandemics.

The study contributes to the body of knowledge in that it develops a managerial framework to position the QA of Cb-CLSC during pandemics and post-pandemics by taking lessons from how COVID-19 has impacted the existing QA systems and has been managed successfully. It is original research with invaluable primary data in the form of surveys and interviews from experts within the Hong Kong SAR–Mainland China links, typically known as the world’s factory.

While COVID-19 mitigation measures (CMMs) aided in steady recovery during the pandemic, they also impeded movement across economies/borders, affecting quality assurance (QA) of Cross-border Construction Logistics and Supply Chain (Cb-CLSC). However, prior studies on the pandemic in the construction project industry have not revealed how CMMs have impacted QA. Thus, this study aims to evaluate the impact of the CMMs on the QA of Cb-CLSC.

This is achieved by adopting an embedded mixed-method approach involving a desk literature review and engaging 150 experts from different economies across the globe using expert surveys, and results verified via semi-structured expert interviews. Structural equation modelling-based multiple regression analysis (SEM-MRA) was integrated to examine the impact of the CMMs on the QA, along with descriptive and content analysis.

The study confirmed that CMMs have not only impacted the QA negatively but also influenced the positioning of the QA for the post-pandemic era and probably to survive the risks of future pandemics. Among all the identified CMMs, the top three critical measures include “lockdown (CMM2)”, “use of personal protective equipment, such as nose masks, disinfects, etc. (CMM5)”, and “electronic/virtual meetings (CMM7)”. However, CMM5 possesses the highest contributory power to form CMM in impacting the QA, and this can be regarded as largely positive by strengthening health and safety management systems. Its negative impact lies with the project cost increment and the inconveniences of using nose and face masks.

This study provides a better understanding to construction practitioners and policy makers on how the pandemic policies, i.e. CMMs, have impacted QA and can aid in formulating planning and operational decisions to adequately position the QA for the post-pandemic era and to endure the risks of future pandemics.

The study contributes to knowledge in that it provides a better understanding of how the pandemic policies, such as CMMs, have impacted QA and can aid in formulating planning and operational decisions to adequately position the QA for the post-pandemic era and to endure the risks of future pandemics. This area of study has been given limited attention among prior studies during the pandemic.