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Soybean oil was epoxidized in situ under established conditions. The produced epoxidized soybean oil was subjected to a sulfur containing compound of the formula (5‐phenyl‐1,3,4‐oxadiazole‐2‐(3H)‐thiones) and four of its derivatives (p‐chloro‐, p‐iodo‐, p‐methyl‐ and p‐methoxy‐) in sealed ampoules under inert atmosphere at 180‐2308C (according to the melting point of each sulfur compound). The produced adducts were added to three varnishes based on alkyd resin, chlorinated rubber and a vinyl chloride copolymer to evaluate them as corrosion inhibitors for steel surfaces. It was found that these adducts can act as good corrosion inhibitors and their efficiencies depend principally on the substituted functional group.

Traditional analytical methods are often time-consuming and require bulky instruments, making their widespread implementation challenging. This paper aims to represent the principal concepts of biosensors as an introduction of this technology to readers and offers a comprehensive understanding of its functions.

The authors provide descriptions of the components, characteristics and advantages of biosensors along with the immobilization methods, followed by a brief discussion.

A biosensor is an analytical device comprising a specific biomolecule and a transducer in conjunction with an output system. The biomolecule recognizes a specific target which leads to a change in physicochemical properties of a system. This biorecognition phenomenon is later converted into a detectable signal by the transducer. Biosensors can essentially serve as rapid and cost-effective devices with excellent sensitivity and specificity for critical purposes in innumerable fields, ranging from scientific research to day-to-day applications.

Here, the authors explain and discuss the approaches and challenges with the aim of leading to an interest in biosensor development and improving their applications.

This study aims to propose a sensitivity-based methodology for the optimum accommodation of distributed generation (DG) units in meshed power networks with appropriate technologies. The effect of load variation is incorporated into the proposed methodology to identify the most trusted locations for DG placement.

The effectiveness of minimizing active power losses is considered a key criterion. A priority list comprising both sensitivity indexes and realistic indicators is deduced to rank the optimum sites for the placement of DG units. A sorting index for distinguishing the suitable DG type(s) for each candidate location is organized. Three common DG types are considered in this work. The modified IEEE 30-bus meshed system is chosen to perform the proposed methodology.

Results demonstrate that the obtained priority index can be used to achieve the best real loss minimization rates. Numerous load buses can be safely excluded as candidate locations using the proposed approach. Consequently, the methodology can minimize the computational process of diagnosing the optimum sites for DG accommodation.

The findings determine that instead of installing many DG units at various locations with one DG type, a few certain load buses can be used to accommodate more than one DG type and significantly reduce losses.

This study is part of the valorization of local materials and the reuse of industrial waste in construction. This study aims to improve the physical-mechanical properties of sand concrete. This work is a continuation of previous studies conducted on sand concrete, the purpose of which is to introduce industrial waste into this material. For this purpose, a glass waste in powder form is added.

This study is focused on the effect of adding glass powder (GP) whose mass percentage varies from 0 to 40% with an interval of 10% to target the right composition that ensures the best compromise between the characteristics studied.

The results found show that the workability and density of the studied concretes decreased with increasing GP dosage. Indeed, the optimal addition which constitutes the best compromise between the studied properties is 10% of GP. Improvements of up to about 9% in the case of flexural strength and about 18% in the case of compressive strength. The thermal conductivity has been reduced by 12.74%, the thermal diffusivity which characterizes the notion of thermal inertia has been reduced by about 4% and the specific heat mass has been reduced by 7.80%. Also, the shrinkage has been reduced by about 20%. The microstructure of the studied composite shows a good homogeneity between the aggregates. Finally, the addition of GP to sand concrete gives very encouraging results.

The interest of this study is in two parts. The first one is the exploitation of local materials: dune sand, river sand and limestone filler to meet the growing demand for construction materials. And the second one is the reuse of glass waste, in the form of powder (GP), to solve the environmental problem. All this participates in the improvement of the physical-mechanical properties of sand concrete and the extent of its response to the development of an economical structural concrete.

The aim is to analyze the European eco-management because the global warming has become a topical issue impacting the whole world. Individual countries are trying to minimize all the catalysts of global warming, such as carbon emissions. This paper addresses this issue and analyzes the performance of European eco-management for the purpose of future energy investments being environmentally.

This paper develops a fuzzy decision-making model to study the performance indicators of selected countries based on EMAS III standard. It employs interval type-2 fuzzy DEMATEL to evaluate the performance factors and TOPSIS methodology to assess five selected European countries' performance in relation to eco-friendly, emission and renewable energy.

Eco-friendly energy plays the most critical role in this respect followed by emissions and renewable energy which constitute significant factors. The novelty of this study is identifying significant criteria regarding environmental and energy efficiency of investments and making performance assessments of European countries with a new fuzzy decision-making model. Both expert opinions and datasets are used for the analysis. This paper supports previous research about energy efficiency investments in Europe.

The innovative feature of this study is identifying significant criteria regarding environmental and energy efficiency of investments and assessing the performance of European countries with a new fuzzy decision-making model. The fact that the analysis only concerns the European region is an important limitation. In future analyses, other groups of countries can be examined. Innovations can be made regarding the method applied. In this context, analyses can be done utilizing different fuzzy numbers. Finally, the importance of the criteria can be calculated with other methods such as SWARA.

The paper fills the gap in performance analysis of European eco-management for environmentally friendly and efficient energy investments is done in this manuscript.

Analysis of European eco-management performance was done for environmentally friendly and efficient energy investments. A fuzzy decision-making model is constructed. The paper fills the gap in performance analysis of European eco-management for environmentally friendly and efficient energy investments.

The last few years have seen a stronger emphasis on patient-centred care within the international healthcare setting. Patient-centred care is clearly perceived to be important to optimise the satisfaction and well-being of patients. The purpose of this paper is to review current patient-centred practices for outpatients in both private clinics and public hospitals in Dubai. Such a comparison contributes to the identification of best management practices as a means of enhancing healthcare delivery.

This study is based on an independent survey consisting of self-administered questionnaires, in which patients were asked to rate several aspects of private clinics or government hospitals in Dubai. The questionnaire used has been drawn from the Consumer Assessment of Healthcare Providers and Systems Clinician and Group Survey, Version 3.0. Responses from 420 patients form a data set that is analysed quantitatively.

In total, 420 respondents took part in this survey. The results of the survey show that there is a considerable difference between the expectation levels of patients from government hospitals and patients from private clinics. Patients from government hospitals consistently show that time is a critical aspect of the service received, with 68 per cent of the respondents reporting this issue. Additionally, poor customer care, as reported by 14 per cent of the respondents, is also a critical issue. Timely service and appointments are among the main factors that contribute to patient satisfaction. Patients in private clinics, instead, particularly value clear explanations from doctors and nurses – this is corroborated by the fact that 11 per cent of the respondents reported appreciation of this type of service.

This paper draws attention to a patient-centric perspective of healthcare, and highlights the importance of educating patients through clear explanations.

Little evidence exists on the standards of healthcare in Dubai. The authors explore this area and present direct evidence on quality standard implementation, identify implementation shortcomings and make recommendations for future research and practice.

The purpose of this paper is to study the corrosion protective properties of modified urea and/or thiourea formaldehyde resins for steel surface.

Three butyl alcohol modified amino resins were laboratory prepared. The three modified resins were characterized using thermal gravimetric analysis and infrared; the solid content and refractive index of each were also measured.

The resins that contain both nitrogen and sulphur have excellent corrosion inhibitive activity compared with that containing nitrogen only.

The modified resins were based on urea formaldehyde resin, mixed urea and thiourea formaldehyde resin and thiourea formaldehyde resin, respectively.

The prepared resins were introduced in different coating formulations based on short‐oil alkyd resin, medium‐oil alkyd resin and plasticized chlorinated rubber. They were then tested and evaluated for corrosion protection of steel surfaces.

All the prepared resins show promising results for corrosion protection of steel surfaces.

Small businesses and start-ups have started to reopen post coronavirus disease 2019 (COVID-19) lockdowns but are facing numerous challenges mainly due to changed customer preferences and the need to fine-tune the business models. This research aims to identify the important aspects that start-ups need to focus on, as they weather the COVID-19 pandemic storm.

Research uses constructivist grounded theory methodology to analyse data collected through in-depth semi-structured interviews with entrepreneurs and senior employees at start-ups. A conceptual model based on nine categories impacting a start-up’s performance is investigated. Interview memos are thematically analysed to identify repeated ideas, concepts or elements that become apparent.

Study reveals that employees’ and customers’ safety, prudent cost management and online presence/doorstep services are key for start-ups to succeed today's changed business landscape due to COVID-19.

Findings act as a practical guide for start-ups in setting mechanisms, optimizing operations and fine-tuning strategy to address COVID-19 challenges. Start-ups are advised to evaluate the implications of the three findings on their respective businesses to successfully tackle the challenges posed by COVID-19.

This research, being cognizant of a start-up’s unique characteristics and nuances, takes a fresh approach to identify key aspects that start-ups need to focus on and fine-tune in the wake of COVID-19. The paper enriches scientific research of understanding impact of COVID-19 on organizations by specifically surfacing how start-ups can learn and adapt by knowing how other start-ups are surviving today.

The purpose of this paper is to synthesize chitosan, N-octyl chitosan (NOCh) and carboxymethyl chitosan (CMCh) derivative from prawn shell wastes and identify their applications as modifiers on cellulosic fibres, jute and cotton, to develop quality textile fibres.

Chitosan was obtained by deacetylation of chitin. NOCh was obtained by reductive amination of chitosan. Water-soluble CMCh was prepared by reacting chitosan with monochloroacetic acid in aqueous alkaline media at ambient conditions. Chitosan, NOCh and CMCh were applied on cellulosic fibres, and structure and physico-chemical characteristics of chitosan derivatives and modified fibres were investigated and analysed.

The molecular weight, degree of deacetylation and ash content of prepared chitosan were 1,39,958 Da, 85 and 2.33 per cent, respectively. The moisture content, water holding capacity and total nitrogen content were above 10, 450 and 6.5 per cent, respectively. Average degree of substitution of CMCh was 0.82 as determined by titrimetric analysis. Fourier transform infrared spectroscopy (FTIR) spectra showed characteristic peaks of carbonyl group at 1,659 cm⁻¹, –NH2 at 1,600 cm⁻¹, symmetric stretching of C-H in the methyl group at 1,520 cm⁻¹ and carboxylic group at 1,737 cm⁻¹. Thermograms showed moderate thermal stability in treated fibres compared to untreated fibres. Surface morphology of the modified fibres exhibited smoother surface due to the absorption of chitosan, NOCh and CMCh.

Modification of jute and cotton by sorption of NOCh and CMCh introduced new functional groups on the fibre surface with chemical bonding, which was confirmed by FTIR. Surface morphology of the fibres was carried out by scanning electron microscopy. As the modified fibres also showed good dyeability and colour fastness as well as other properties, the chitosan derivatives as a textile modifier would be helpful to avoid synthetic petroleum-based chemical modifiers as well as to manage the environmental pollution from prawn shell waste and other toxic chemicals.

The purpose of this paper is to evaluate the air permeability of knitted fabrics containing elastane fibre and their seams applying both the new approach based on fabric thickness measurement at different pressures and standard method.

Investigations were performed with commercially available eight polyester knitted fabrics containing different elastane yarn proportion. Bonded seams were laminated applying the urethane thermoplastic adhesive film of 0.175 mm thickness. Bonds were laminated by heat at 5.6 kPa pressure applying pressing device GTK DEA 25 R at 140°C temperature for 40 s duration. Sewn seams were assembled with 607 covering chain stitch applying 5.0 stitches per cm density and 512 overedge chain stitch applying 5.0 stitches per cm density. Specimens without and with the seams were conditioned in standard atmosphere conditions according to the standard LST EN ISO 139 before air permeability testing according to the standard LST EN ISO 9237. Standard thickness of the investigated knitted fabric was determined according to the standard EN ISO 5084. It is known from literature that the porosity is dominant factor influencing the air permeability of knitted fabrics. Therefore, the assumption was made that due to fabric porosity knitted fabric thickness being measured at different pressures also may differ. Thus, the permeability property may also be related to the difference between fabric’s thicknesses being measured under different pressures which may be applied with different material thickness gauges.

There was shown that fabric assemblies make the significant influence on the textile permeability to air. The results obtained indicate that the air permeability of the investigated knitted fabrics depends not only on their structure parameters but also on the fabric seam type. Air permeability of the specimens with the seams was lower than one of specimens without the seams. The highest decrease in permeability which ranged from 19.9 per cent up to 60.0 per cent was determined for the bonds. Fabric specimens with 607 covering chain stitch seam were in the second place with regard to the previously considered parameter. And, their permeability was decreased from 0.6 per cent up to 52.6 per cent. Changes in the air permeability of the specimens with 512 overedge chain stitch seam were lowest in the range of investigated assemblies. Based on the determined results, it was concluded that the thickness difference of the specimens with and without seams measured at different pressures is related to fabric porosity which makes the significant influence on the air permeability.

The samples of investigated fabrics were taken from the two companies which manufactures leisure clothing and sportswear such as skiing or swimming costumes, etc. Thus, the obtained investigation results are significant not only for clothing science but also leads the improvement of clothing quality in fashion industry.

Assuring the comfort of the human body is one of the most important functions of clothing, especially of sportswear and leisure wear. Knitted fabrics should not only be elastic, but also have high air permeability for easily transmit of the perspiration from the skin to the atmosphere, thus making the wearer to feel comfortable. In this research, the air permeability of commercially available polyester knitted fabrics containing different amount of elastane was investigated and the influence of fabric assemblies on the air permeability property was evaluated. A new approach based on the fabric thickness measurement at different pressures and the standard methods for the evaluation of air permeability were used.