The demand for corrosion-resistant and mechanically reliable metallic components in marine, chemical processing, and energy conversion industries has encouraged the integration of additive manufacturing into industrial production. Wire Arc Additive Manufacturing enables the fabrication of medium- to large-scale complex metallic structures at low cost; however, the high thermal input and layer-by-layer deposition commonly lead to elemental segregation, porosity, and nonuniform microstructures that degrade corrosion performance. This study investigates the influence of a post-deposition aluminizing treatment on the surface characteristics and corrosion behavior of stainless steel ER307 and nickel-based superalloy Inconel 625 produced by Wire Arc Directed Energy Deposition. Microstructural evolution, phase transformation, hardness distribution, and corrosion behavior in a 3.5% sodium chloride environment were examined through microscopy, X-ray diffraction, hardness testing, and electrochemical analysis. The aluminizing process generated localized surface porosity and limited non-uniformity aluminide coatings of approximately 40–50 μm thickness, reduced surface roughness, and markedly improved surface hardness. Electrochemical assessments demonstrated substantial enhancements in corrosion resistance, including a 2.3-fold improvement for stainless steel and a 13.9-fold improvement for Inconel 625. These findings reveal that post-deposition aluminizing effectively mitigates intrinsic surface defects and microchemical heterogeneity, enabling significantly improved durability in chloride-containing environments. This work provides a straightforward and scalable strategy for enhancing the corrosion resistance of wire-arc-manufactured metallic structures and promotes their application in aggressive service conditions.

In the realm of renewable energy systems, the effective selection of Photovoltaic Thermal (PVT) collectors is important. This study delves into the intricacies of choosing optimal PVT collectors available in the market, emphasizing the utility of Multiple Criteria Decision Making (MCDM) methodologies. PVT collectors are differentiated based on various aspects such as their transparent front cover presence and the medium—liquid or air—used for heat transfer. The study methodologically identifies commercially available PVT collectors and establishes key performance indicators for comparison. Using an 11-point fuzzy scale, a weight matrix is determined. Subsequently, advanced MCDM techniques, including PROMETHEE II, TOPSIS, EDAS, and VIKOR, are employed to rank the alternatives. This research not only provides a systematic approach to PVT collector selection but also extends to a MATLAB-based tool for facilitating the process. The results underscore the value of the proposed methodologies in refining the selection of PVT collectors and their potential adaptability to other applications, such as PVT collector design.

Flexible working models are widely used around the world. Furthermore, several countries are currently transitioning to a 4-day workweek. These working models have significant effects on organizational behavior and the environment. The study investigates the employees' attitudes and behaviors toward flexible working and 4-day workweek and the impact on the environment. The semi-structured interview method was used in the study to determine employee attitudes and behaviors; the carbon footprint calculation method was used to determine the environmental impact of a 4-day workweek. According to the study's findings, it has been discovered that there would be a positive impact on socialization, happiness, stress factor, motivation, personal time, mental health, comfort, work-life balance, time-saving, willingness, positive working environment, personal time, and physical health. Furthermore, a 4-day workweek reduced commuting emissions by 20%, resulting in a 6,07 kg tCO₂e reduction per person. As a result, the study attempted to draw attention holistically to the positive effects of the flexible working model and 4-day workweek. The study is intended to serve as a tool for decision-makers and human resource managers.

Photovoltaic-thermal (PVT) solar collector technologies are considered a highly efficient solution for sustainable energy generation, capable of producing electricity and heat simultaneously. This paper reviews and discusses different aspects of PVT collectors, including fundamental principles, materials, diverse classifications, such as air-type and water-type, and different cooling mechanisms to boost their performance, such as nano-fluids, Phase Change Materials (PCMs), and Thermoelectric Generators (TEGs). At the system level, this paper analyses PVT technologies’ integration in buildings and industrial applications and gives a comprehensive market overview. The methodology focused on evaluating advancements in design, thermal management, and overall system efficiency based on existing literature published from 2010 to 2025. From the findings of various studies, water-based PVT systems provide electrical efficiencies ranging from 8% to 22% and thermal efficiencies between 30% and 70%, which are almost always higher than air-based alternatives. Innovations, including nanofluids, phase change materials, and hybrid topologies, have improved energy conversion and storage. Market data indicates growing adoption in Europe and Asia, stressing significant investments led by Sunmaxx, Abora Solar, Naked Energy, and DualSun. Nonetheless, obstacles to PVT arise regarding aspects such as cost, design complexity, lack of awareness, and economic incentives. According to the findings of this study, additional research is required to reduce the operational expenses of such systems, improve system integration, and build supportive policy frameworks. This paper offers guidance on PVT technologies and how they can be integrated into different setups based on current normativity and regulatory frameworks.

Climate change, as a critical global concern, has fueled our efforts to address it through different strategies. In response to the critical worldwide issue of climate change, we suggested a Photovoltaic (PV) system at the National University of Sciences and Technology (NUST) in Islamabad, Pakistan (latitude: 33.724530 N, longitude: 73.046869, terrain elevation: 552 m). Islamabad is located in a region blessed with enormous solar resources, boasting a daily horizontal solar irradiance of 1503.45 kWh/m² and an average daily solar irradiance of 5.89 kWh/m², with an exceptional solar fraction of 98.99%. The ambient air temperature, averaging 23.21 °C, reaches its maximum in June and its minimum in December. Our research thoroughly evaluates the system’s performance, accounting for various losses and utilizing modern PVsyst software. Over the course of 18 years, our PV system is expected to save 75,478.60 tons of CO₂, the equivalent of planting 348,754 teak trees. Furthermore, the cost of energy generation is an affordable 0.0141 US $/kWh, much lower than traditional rates, including the Sherif cost of 0.028$/kWh. Along with the performance research, we conducted a detailed cost analysis, projecting the starting cost and cash flow, and discovered that the plant would be in surplus within 12 years of installation. Our system is positioned to generate 11,270,771 kWh/year with a respectable performance ratio (PR) of 76.2% and a Capacity Utilization Factor (CUF) of 16%. Our findings not only highlight the potential of renewable energy but also provide important insights for future sustainable energy programs.

Concentrating Photovoltaic Thermal (CPVT) collectors are suitable for integration in limited roof space due to their higher solar conversion efficiency. Solar sunlight can be used more effectively by CPVT collectors in comparison to individual solar thermal collectors or PV modules. In this study, the experimental investigation of a novel CPVT collector called a PC (power collector) has been carried out in real outdoor conditions, and the test set-up has been designed based on ISO 9806:2013. A quasi-dynamic testing method has been used because of the advantages that this method can offer for collectors with a unique construction, such as the proposed collector, over the steady-state testing method. With a quasi-dynamic testing method, it is possible to characterize the collector within a wide range of incidence angles and a complex incidence angle modifier profile. The proposed novel collector has a gross area of 2.57 m². A maximum power output per collector unit area of 1140 W is found at 0 °C reduced temperature (1000 W/m² irradiance level), while at a higher reduced temperature (70 °C), it drops down to 510 W for the same irradiance level. The data have been fitted through a multiple linear regression method, and the obtained efficiency curve coefficients are 0.39, 0.192, 1.294, 0.023, 0.2, 0, −5929 and 0 for K_θd, b₀, c₁, c₂, c₃, c₄, c₅ and c₆, respectively. The experimental characterization carried out on the collector proved that the output powers calculated by using the obtained parameters of the quasi-dynamic testing method are in good agreement with experimental points.