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The purpose of this study is to determine the material extrusion (MEX) printability envelope of a new kind of low-viscosity powder-binder feedstocks using rheological properties.

Formulation of 13 feedstocks (variation of solid loading 60–67 Vol.% and thickening agent proportion 3–15 Vol.%) that were characterized and printed at different temperatures.

Three rheological models were successfully used to define the viscosity envelope, producing stable and defect-free printing. At a shear deformation rate experienced by the feedstock in the nozzle ranging from 100 to 300 s^–1, it was confirmed that metal injection molding (MIM) feedstocks exhibiting a low viscosity between 100 and 150 Pa s could be printed using an extrusion temperature as low as 85 °C.

MEX can be used in synergy with MIM to accelerate mold development for a new injected part or simply as a replacement for MIM when the cost of the mold becomes too high for very small production volumes.

Correlation between the rheological properties of this new generation of low-viscosity feedstocks and MEX printability has been demonstrated for the first time.

This study aims to enhance merging of additive manufacturing (AM) techniques with powder injection molding (PIM). In this way, the prototypes could be 3D-printed and mass production implemented using PIM. Thus, the surface properties and mechanical performance of parts produced using powder/polymer binder feedstocks [material extrusion (MEX) and PIM] were investigated and compared with powder manufacturing based on direct metal laser sintering (DMLS).

PIM parts were manufactured from 17-4PH stainless steel PIM-quality powder and powder intended for powder bed fusion compounded with a recently developed environmentally benign binder. Rheological data obtained at the relevant temperatures were used to set up the process parameters of injection molding. The tensile and yield strengths as well as the strain at break were determined for PIM sintered parts and compared to those produced using MEX and DMLS. Surface properties were evaluated through a 3D scanner and analyzed with advanced statistical tools.

Advanced statistical analyses of the surface properties showed the proximity between the surfaces created via PIM and MEX. The tensile and yield strengths, as well as the strain at break, suggested that DMLS provides sintered samples with the highest strength and ductility; however, PIM parts made from environmentally benign feedstock may successfully compete with this manufacturing route.

This study addresses the issues connected to the merging of two environmentally efficient processing routes. The literature survey included has shown that there is so far no study comparing AM and PIM techniques systematically on the fixed part shape and dimensions using advanced statistical tools to derive the proximity of the investigated processing routes.

Personal Protective Equipment plays an inevitable part in the current scenario of pandemics in the world. A novel coronavirus, Severe Acute Respiratory Syndrome-Corona Virus-2 (SARS-Cov 2), began as an outbreak of pneumonia in Wuhan, China, in late December 2019, and quickly spread worldwide. It quickly escalated into an international public health crisis. This opened up the high demand for the innovation and research of new materials in the Personal Protective Equipment industry.

PubMed, Embase and Google Scholar were searched for relevant literature regarding personal protective equipment and the information was organized in a systematic way.

There are no adequate number of studies taken up in the field of use of textiles in medical applications especially with PPEs.

This structured review will generate a sense of the significance of using PPE for controlling pandemics and also awaken need for additional research and innovations in this area.

The authorities of the management should take timely intervention in choosing the right material for their PPE in their hospitals. Hence health care professionals teams have an inevitable role in preventing the adverse environmental impact due to the inadvertent disposal of PPEs.

There is a lack of systematic way of disposing contaminated single-use face masks in a safe, environmentally acceptable manner. The dumping of single-use PPE in domestic garbage has had an adverse effect on the environment. Mismanaged plastic waste endangers the health of ecosystems by polluting marine and terrestrial environments, posing a significant risk of ingestion or injury to animals and contaminating habitats.

This review article provides an in-depth review of the use of different materials in PPE and challenges regarding its long-term use and implications on the environment.

As an advanced manufacturing method, additive manufacturing (AM) technology provides new possibilities for efficient production and design of parts. However, with the continuous expansion of the application of AM materials, subtractive processing has become one of the necessary steps to improve the accuracy and performance of parts. In this paper, the processing process of AM materials is discussed in depth, and the surface integrity problem caused by it is discussed.

Firstly, we listed and analyzed the characterization parameters of metal surface integrity and its influence on the performance of parts and then introduced the application of integrated processing of metal adding and subtracting materials and the influence of different processing forms on the surface integrity of parts. The surface of the trial-cut material is detected and analyzed, and the surface of the integrated processing of adding and subtracting materials is compared with that of the pure processing of reducing materials, so that the corresponding conclusions are obtained.

In this process, we also found some surface integrity problems, such as knife marks, residual stress and thermal effects. These problems may have a potential negative impact on the performance of the final parts. In processing, we can try to use other integrated processing technologies of adding and subtracting materials, try to combine various integrated processing technologies of adding and subtracting materials, or consider exploring more efficient AM technology to improve processing efficiency. We can also consider adopting production process optimization measures to reduce the processing cost of adding and subtracting materials.

With the gradual improvement of the requirements for the surface quality of parts in the production process and the in-depth implementation of sustainable manufacturing, the demand for integrated processing of metal addition and subtraction materials is likely to continue to grow in the future. By deeply understanding and studying the problems of material reduction and surface integrity of AM materials, we can better meet the challenges in the manufacturing process and improve the quality and performance of parts. This research is very important for promoting the development of manufacturing technology and achieving success in practical application.

The purpose of this study is to explore the understanding and observance of the program “This School is a Zone of Peace” (SZOP) in schools where conflict and violence are not prevalent.

This paper followed a qualitative research tradition – narrative inquiry. Eight teachers and a school head participated in the study. Data were gathered through nonparticipant observation, photography and focus group discussion with photo elicitation.

The participants elucidated the declaration, “This School is a Zone of Peace,” as a message of assurance to the community that the school is a home for learners that is welcoming and violence free. Furthermore, learners in a school that is a zone of peace are honed holistically with the participation, cooperation and togetherness of the school community members. Teachers at the forefront viewed themselves as mentors, implementers and models. Teachers contended that peacebuilding practices in schools could be sustained through regular implementation, encouraging others to get involved and have commitment.

A handful of articles have illustrated the essence of the School as Zone of Peace program, which pointed out to create a culture of peace in schools; however, it leaned toward the negative conception of peace – the absence of conflict and violence. This study bared additional insights and fresh perspectives of the SZOP initiative observed in schools with different contexts and experiences that may be helpful to policymakers for the enhancement of the adapted program with the goal of peacebuilding to making schools highly functional.

The purpose of this study is to investigate the gendered ideas and ideals attached to an imagined ideal Entrepreneur in a post-industrial rural community in Sweden. While research has not yet clearly explained how the ideal entrepreneur is constructed, the result, i.e. the gendered representations of entrepreneurs, is well-researched. Previous results indicate a prevalent portrayal of entrepreneurship as a predominantly masculine construct characterised by qualities such as self-made success, confidence and assertiveness.

Ethnographic fieldwork was conducted in a community that is attempting to re-brand itself through garden tourism. Through inductive reasoning, this study analyses the gendered ideas and ideals regarding the community’s imagined ideal Entrepreneur who is to help the community solve its problems.

This study finds that the community forges the Entrepreneur into an imagined masculine ideal as holy, a saviour and a god and is replacing its historical masculine ironmaster with a masculine Entrepreneur. This study develops forging as a metaphor for the construction of the masculine ideal Entrepreneur, giving the community, rather than the entrepreneur himself, a voice as constructors. From social constructionism, this study emphasises how gendered ideas and ideals are shaped not only by the individual realities but more so in the reciprocal process by the realities of others.

The metaphor of forging adds an innovative theoretical dimension to the feminist constructionist approach and suggests focusing on how the “maleness” of entrepreneurship is produced and reproduced in the local. Previously, light has been shed on how male entrepreneurs perform their identities collectively; the focus of this study is on the social construction of this envisioned Entrepreneur within a rural community. The development of forging thus contributes as a way of analysing entrepreneurship in place. The choice of an ethnographic study allowed the authors to be a part of the real-life world of community members, providing rich data to explore entrepreneurship and gender.

This study aims to present an experimental approach to develop a high-strength 3D-printed recycled polymer composite reinforced with continuous metal fiber.

The continuous metal fiber composite was 3D printed using recycled and virgin acrylonitrile butadiene styrene-blended filament (RABS-B) in the ratio of 60:40 and postused continuous brass wire (CBW). The 3D printing was done using an in-nozzle impregnation technique using an FFF printer installed with a self-modified nozzle. The tensile and single-edge notch bend (SENB) test samples are fabricated to evaluate the tensile and fracture toughness properties compared with VABS and RABS-B samples.

The tensile and SENB tests revealed that RABS-B/CBW composite 3D printed with 0.7 mm layer spacing exhibited a notable improvement in Young’s modulus, ultimate tensile strength, elongation at maximum load and fracture toughness by 51.47%, 18.67% and 107.3% and 22.75% compared to VABS, respectively.

This novel approach of integrating CBW with recycled thermoplastic represents a significant leap forward in material science, delivering superior strength and unlocking the potential for advanced, sustainable composites in demanding engineering fields.

Limited research has been conducted on the in-nozzle impregnation technique for 3D printing metal fiber-reinforced recycled thermoplastic composites. Adopting this method holds the potential to create durable and high-strength sustainable composites suitable for engineering applications, thereby diminishing dependence on virgin materials.

This paper aims to evaluate the mechanical behaviour of polycarbonate/acrylonitrile butadiene styrene (PC/ABS) filaments for fusion filament fabrication (FFF). PC/ABS have emerged as a promising material for FFF due to their excellent mechanical properties. However, the optimal processing conditions and the effect of the blending ratio on the mechanical properties of the resulting workpieces are still unclear.

A statistical factorial matrix was designed, including infill pattern, printing speed, nozzle size, layer height and printing temperature as factors (with three levels). A total of 810 workpieces were printed using PC/ABS blends filament with the FFF. The workpieces’ finishing and mass were evaluated. Tensile tests were performed. Analysis of variance was performed to determine the main effects of the processing conditions on the mechanical properties.

The results showed that the PC/ABS (70/30) exhibited higher tensile. Tensile rupture corresponded to 30% of the tensile strength. The infill pattern showed the highest contribution to the responses. The concentric pattern showed higher tensile strength. Tensile strength and mass ratio demonstrated the influence of mass on tensile strength. The influence of printing parameters on deformation depended on the blend proportions. Higher printing speed and lower layer height provided better quality workpieces.

This study has implications for the design and manufacturing of three-dimensional printed parts using PC/ABS filaments. An extensive experimental matrix was applied, aiming at a complete understanding of mechanical behavior, considering the main printing parameters and combinations not explored by literature.

The purpose of this study is to propose and test an extended theory of planned behavior model to explain the significance of social media influencers’ credibility, social media usage (SMU) and social media marketing while simultaneously examining females’ intentions to purchase cosmetics online.

An online questionnaire was used to collect data from 386 female consumers of cosmetics, and the data were analyzed using partial least squares structural equation modeling (PLS-SEM) with the help of SmartPLS version 4.

First, the results indicated that SMU, social media influencers’ credibility and social media marketing significantly and positively impact the theory of planned behavior components, namely, attitude, subjective norms (SNs) and perceived behavioral control (PBC). Second, results confirmed that attitude, SNs and PBC significantly and positively influenced female consumers’ online purchase intentions (OPIs).

To the best of the authors’ knowledge, this study is one of the first to examine an integrated model that consisted of SMU, social media marketing and social media influencers along with the theory of planned behavior constructs in their proposed research model in the context of cosmetics in India. The study also enriched the body of knowledge about using the PLS-SEM approach to predict OPI for cosmetics.

The purpose of this paper is to investigate the effects of chloride ion concentration and applied bias voltage on the electrochemical migration (ECM) behavior between Cu and Ag under an NaCl thin electrolyte layer (TEL).

A self-made experimental setup for the ECM behavior between Cu and Ag was designed. An HD video measurement microscopy was used to observe the typical dendrite/corrosion morphology and pH distribution. Short-circuit time (SCT), short-circuit current density and the influence of the galvanic effect between Cu and Ag on their ECM behavior were studied by electrochemical tests. The surface morphology and composition of dendrite were characterized by FESEM/EDS.

The SCT increased with increasing NaCl concentration but decreased with increasing applied bias voltage, and the SCT between Cu and Ag was less than that between Cu and Cu because their galvanic effect accelerated the dissolution and migration of Cu. When NaCl concentration was less than or equal to 6 mmol/L, cedar-like dendrite was formed, whereas no dendrite formed and only precipitation occurred at high chloride ion concentration (100 mmol/L). The composition of the dendrite between Cu and Ag was copper.

The significance of this study is to clarify the ECM failure mechanism of printed circuit board (PCB) with an immersion silver surface finish (PCB-ImAg).

This study provides a basic theoretical basis for the selection of protective measures and metal coatings for PCB.

The social implication of this study is to predict the service life of PCB.

The ECM behavior of dissimilar metals under a TEL was investigated, the influence of the galvanic effect between them on their ECM was discussed, and the SCT increased with increasing NaCl concentration.