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The purpose of this study is to investigate the presence of silicon dioxide (SiO₂) nanoparticles in o-toluidine monomer as a reactant and ammonium persulfate as an oxidant to obtain the poly(o-toluidine) (POT)/SiO₂ nanocomposites by oxidative polymerization method.

Fourier transformation infrared spectroscopy, X-ray diffraction and field emission scanning electron microscopy were used to characterize the structural properties of the composite. POT/SiO₂ nanocomposites were mixed with acrylic resin through a solution mixing method and the composites were coated onto the surface of mild steel. Electrochemical measurements were used to determine the corrosion protection efficiency (P.E.%) of polymer composite coatings using 3.5% NaCl solution as corrosion environment.

The results obtained reveals that the POT/SiO₂/acrylic resin composite coatings have got higher corrosion P.E.% than that of POT/acrylic resin coatings.

The formation of uniformly passive layer in the POT/SiO₂ composite was used to enhance the P.E.% on mild steel surface. The POT/SiO₂/acrylic resin nanocomposites showed effective anticorrosive behavior on mild steel in 3.5% NaCl solution.

The color painting of ancient buildings has high historical and artistic value but is prone to aging due to long-term outdoor exposure. The purpose of this study is to develop a new type of sealing coating to mitigate the impact of ultraviolet (UV) light on color painting.

The new coating was subjected to a 500-h UV-aging test. Compared with the existing acrylic resin Primal AC33, the UV aging behavior of the new coating, such as color difference and gloss, was studied with aging time. The Fourier infrared spectra of the coatings were analyzed after the UV-aging test.

Compared with AC33, the antiaging performance of SF8 was substantially improved. SF8 has a lower color difference value and better light retention and hydrophobicity. The Fourier transform infrared spectroscopy results showed that the C-F bond and Si-O bonds in the resin of the optimized sealing coating protected the main chain C-C structure from degradation during the aging process; thus, the resin maintained good stability. The hindered amine light stabilizer TN292 added to the coating inhibited the antiaging process by trapping active free radicals.

To address the problem of UV aging of oil-decorated colored paintings, a new type of sealing coating with excellent antiaging properties was developed, laying the foundation for its demonstration application on the surface of ancient buildings.

The purpose of this study is to distinguish the difference in tribological behavior of functionally graded composites in two sliding modes, namely, unidirectional and reciprocating.

A356-(10 Wt.%)SiCp functionally graded composite material (FGM) was prepared by vertical centrifugal casting and then a comparison was made between the tribological characteristics using pin-on-disk and pin-on-reciprocating plate configurations under identical operating conditions (sliding distance (s): 350 m; load (W): 30 = W = 120 N, in steps of 30 N; and velocity (v): 0.2 = v = 1.2 m/s, in steps of 0.2 m/s). Two types of test pins were considered, namely, a test pin taken from the outer zone of the FGM with maximum particle concentration and a test pin taken from the inner zone of the FGM in a matrix-rich region.

The study revealed that, for the test pin taken from the outer zone of the FGM in the low-velocity range (0.2–0.4 m/s), the reciprocating wear of the friction pair was dominant, while unidirectional wear was dominant in the velocity range of 0.6–0.8 m/s for the entire load range investigated. However, when the velocity was increased from 1.0 to 1.2 m/s, conflicting nature of dominancy in the wear characteristics of the friction pair was observed, depending on the loading condition. In addition, the inner zone FGM pin underwent seizure in the reciprocating mode, whereas this phenomenon was not seen in the unidirectional mode.

Differences in wear and friction characteristics of FGM friction pairs in two different sliding modes were investigated over a wide range of operating parameters.

The purpose of this paper is to outline the main features concerning the optimization of printed circuit board (PCB) fabrication by improving the manufacturing process productivity.

The author explored two different approaches to increase the manufacturing process productivity of PCBs. The first approach involved optimization of the PCB manufacturing process as a whole. The second approach was based on increasing the process productivity at the operational level.

To reduce the total manufacturing time, two heuristic algorithms for solving flowshop scheduling problems were designed. These algorithms were used for the computation of an optimal PCB manufacturing schedule. The case study shows both mono‐ and bi‐criteria optimization of the PCBs manufacturing.

While the input data used in the case study were based on random numbers, the mathematical considerations drew only the main directions for manufacturing process optimization.

The paper shows two original heuristic algorithms for solving the flowshop scheduling problem, with high performance according to the best heuristics in the field. Besides their performances, these algorithms have the advantage of simplicity and ease of implementation on a computer. Using these algorithms, the optimal schedule for the PCB manufacturing process was calculated. For the case of the bi‐criteria optimization, the study of points which belong to the Pareto‐optimal set are presented.

This review provides an overview of recent advances in electrochemical sensors for analyte detection in saliva, highlighting their potential applications in diagnostics and health care. The purpose of this paper is to summarize the current state of the field, identify challenges and limitations and discuss future prospects for the development of saliva-based electrochemical sensors.

The paper reviews relevant literature and research articles to examine the latest developments in electrochemical sensing technologies for saliva analysis. It explores the use of various electrode materials, including carbon nanomaterial, metal nanoparticles and conducting polymers, as well as the integration of microfluidics, lab-on-a-chip (LOC) devices and wearable/implantable technologies. The design and fabrication methodologies used in these sensors are discussed, along with sample preparation techniques and biorecognition elements for enhancing sensor performance.

Electrochemical sensors for salivary analyte detection have demonstrated excellent potential for noninvasive, rapid and cost-effective diagnostics. Recent advancements have resulted in improved sensor selectivity, stability, sensitivity and compatibility with complex saliva samples. Integration with microfluidics and LOC technologies has shown promise in enhancing sensor efficiency and accuracy. In addition, wearable and implantable sensors enable continuous, real-time monitoring of salivary analytes, opening new avenues for personalized health care and disease management.

This review presents an up-to-date overview of electrochemical sensors for analyte detection in saliva, offering insights into their design, fabrication and performance. It highlights the originality and value of integrating electrochemical sensing with microfluidics, wearable/implantable technologies and point-of-care testing platforms. The review also identifies challenges and limitations, such as interference from other saliva components and the need for improved stability and reproducibility. Future prospects include the development of novel microfluidic devices, advanced materials and user-friendly diagnostic devices to unlock the full potential of saliva-based electrochemical sensing in clinical practice.

The study aims to describe the main classes of antioxidants existing in fruit, beverages, vegetables and herbs and the different extraction and application of antioxidants in food. Oxidative degradation of lipids, especially induced by reactive oxygen species, leads to quality deterioration of foods and cosmetics and could have harmful effects on health. A major challenge is to develop tools to assess the antioxidant capacity and real efficacy of these molecules. Recently, many review papers regarding antioxidants from different sources and different extraction and quantification procedures have been published. However, none of them has all the information regarding antioxidants (sources, extraction and application in food).

This paper tries to take a different perspective on antioxidants for the new researcher involved in this field.

Antioxidants from fruit, vegetables and beverages play an important role in human health, for example, preventing cancer and cardiovascular diseases and lowering the incidence of different diseases. A number of plant products act as scavengers of free radical species and so have been classified as antioxidants. Antioxidants are an important group of food additives that have the ability to protect against detrimental change of oxidizable nutrients and consequently they extend shelf-life of foods.

Most of the antioxidants present in foods are phenolic and polyphenolic compounds, but their efficacy in food for the prevention of oxidation or in the body for dealing with oxidative stress and its consequences depends on different factors.

This study collected the last finding in the field of sources and applications of natural antioxidants.

Blockchain and IoT are recently developed technologies for the database creation and smooth functioning of supply chain activities. The purpose of this paper is to analyse the use of blockchain and IoT for green procurement activities. The integration of blockchain and IoT interface can solve many challenges faced by industries having green procurement.

Through a literature survey and interviews with procurement managers from different industries, challenges in green procurement were identified. Elements of blockchain and IoT were analysed to overcome the green procurement challenges. Architecture for blockchain and IoT is developed to be implemented in the green supply chain for a sustainable business.

The challenges of green procurement are categorised and ranked as per the industry survey results. The architecture shows the tasks of blockchain and IoT in green procurement activities.

Green procurement is still at developing stages in India as compared to Europe and many other countries. There is a requirement for more government involvement and participation from industry and customers to implement such methods. Environment issues and challenges faced by industries are addressed.

Blockchain–IoT integration can transform a green supply chain. This research helps industries planning to incorporate blockchain and IoT in identifying the areas to focus and better planning of resources for the successful implementation of smart technologies in their supply chains. Green initiatives ensure global competitiveness as well as recognition at the global level. Green procurement ensures the minimal usage of energy and efficient waste disposal.

The implementation of green procurement and challenges associated with it are addressed in this research. This will work as a framework for industries looking forward to implementing blockchain and IoT in their supply chains for solving green procurement challenges.

The purpose of the paper is to determine the impact of cultural values on the success of TQM implementation in Isfahan University Hospitals (IUHs), Iran, 2004.

In this paper survey questionnaires were used to elicit responses from hospital managers and employees. Data collected included the characteristics of organizational culture in IUHs and the degree of TQM success and its implementation problems in these hospitals.

The paper finds that TQM success in IUHs was medium. Implementation of TQM was very low, low, medium and highly successful respectively in 16.7, 16.7, 58.3 and 8.3 percent of hospitals. TQM had the most effect on process management, focus on customers and leadership and management and less effect on focus on suppliers, performance results, strategic planning and focus on material resources. Human resource problems, performance appraisal and strategic problems were the most important obstacles to TQM success respectively. A total of 75 and 25 percent of hospitals had mechanistic and organic structure respectively. In total 41.6 percent of hospitals had weak organizational culture versus 58.4 percent medium culture. The success of TQM in hospitals with organic organizational structure and medium organizational culture was higher than mechanistic and bureaucratic hospitals with weak organizational culture (p<0.05).

The paper shows that TQM requires a quality‐oriented organizational culture supported by senior management commitment and involvement, organizational learning and entrepreneurship, team working and collaboration, risk taking, open communication, continuous improvement, customers focus (both internal and external), partnership with suppliers, and monitoring and evaluation of quality. By replicating this study in different countries and contexts the results could be very helpful for developing a model of TQM that can be implemented successfully in a cross‐cultural context.

This study aims to investigate the optimal process parameters of the wire-cut electrical discharge machining (WCEDM) for the machining of the GZR-AA7475 hybrid metal matrix composite (HMMC). HMMCs are prepared with 2 Wt.% graphite and 4 Wt.% zirconium dioxide reinforced with aluminium alloy 7475 (GZR-AA7475) composite by using the stir casting method. The objective is to enhance the mechanical properties of the material while preserving its unique features. WCEDM with a 0.18 mm molybdenum wire electrode is used for machining the composite.

To conduct experimental studies, a Taguchi L27 orthogonal array was adopted. Input variables such as peak current (I_p), pulse-on-time (T_ON) and flushing pressure (P_F) were used. The effect of process parameters on the output responses, such as material removal rate (MRR), surface roughness rate (SRR) and wire wear ratio (WWR), were investigated. The grey relational analysis (GRA) is used to obtain the optimal combination of the process parameters. Analysis of variance (ANOVA) was also used to identify the significant process parameters affecting the output responses.

Results from the current study concluded that the optimal condition for grey relational grade is obtained at T_ON = 105 µs, I_p = 100 A and P_F = 90 kg/cm². Peak current is the most prominent parameter influencing the MRR, whereas SRR and WRR are highly influenced by flushing pressure.

Identifying the optimal process parameters in WCEDM for machining of GZR-AA7475 HMMC. ANOVA and GRA are used to obtain the optimal combination of the process parameters.