Ti6Al4V titanium alloys are widely used in a variety of scientific and industrial fields. Laser beam welding is one of the most effective techniques for the joining of titanium plates. The main objective of this study was to investigate the influence of the most important laser parameters on welding performance of titanium alloy in two different physical environments such as air and water (i.e., serum) media. Specifically, the laser beam welding of 2 mm thick Ti6Al4V samples was applied using an Nd:YAG laser in open-air welding using argon as a shielding gas, and in wet welding using a serum environment. The deepest penetration was achieved at −3 mm focal position with 11 J of laser energy in both investigated media (i.e., air and serum). The maximum hardness (1130 HV) was achieved for the focal position of −4 mm in serum medium while it was 795 HV for a focal position of −5 mm in air medium. The minimum (1200 μm and 800 μm) and maximum (1960 μm and 1900 μm) weld widths were observed for air and serum medium, respectively. After the welding process, martensite, massif martensite, and transformed martensite were observed in the microstructure of Ti6Al4V. To the best of our knowledge, the underwater wet welding of titanium alloy was carried out and reported for the first time in this study.

Laser welding is an innovative method that is frequently used and required by different disciplines and represents a technique of choice in a wide range of applications due to important advantages such as precision, speed, and flexibility. However, the welding method must be used properly otherwise it may deteriorate the mechanical properties of the welded metal and its environment. Therefore, the laser parameters should be precisely determined and carefully applied to the sample. The primary objective of this study was to investigate and propose optimal welding parameters that should be adjusted during the neodymium-doped yttrium aluminum garnet (Nd: YAG)-pulsed laser welding of austenitic stainless steel 316L in an air welding environment by using Argon shielding gas and in wet welding settings in serum medium. The investigation of the welding process in serum medium was conducted in order to propose the most suitable welding parameters being important for future possible medical applications of laser welding in in-vivo settings and thus to investigate the possibilities of the welding process inside the human body. In order to evaluate the quality of welding in air and of wet welding (in serum), a detailed parameter study has been conducted by variation of the laser energy, the welding speed and the focal position. The relationship between the depth of penetration and specific point energy (SPE) was also evaluated. The microstructure of the welded metal was examined by an optical microscope and scanning electron microscope (SEM). Based on the microscopy results, it was found that the largest depth of penetration (1380 µm) was achieved with 19 J laser energy in air medium, while the depth reached the largest value (1240 µm) in serum medium at 28 J laser energy. The increasing energy level showed opposite behavior for air and serum. The results of our study imply that when welding of 316L stainless steel is implemented properly in the body fluid, it would be a promising start for future in-vivo studies.

The growing importance of laser material processing technologies in various industries, expanding application areas, and decreasing costs of laser systems make this technology critically important. This paper provides a comprehensive review of the advances, applications and impacts of laser technology in manufacturing, with a particular focus on laser surface treatment, welding, cutting, drilling and cladding. Academic research in this area is leading to the development of innovative manufacturing techniques aimed at improving product quality, designing multi-material components and supporting economic benefits. Numerous studies have been conducted to investigate and optimize the effects of lasers on materials, leading to significant advances in laser materials processing. Key findings highlight the importance of laser surface treatment in enhancing material properties, the versatility and precision provided by laser welding, the advantages of non-contact machining, the high speed and flexibility of laser cutting, and the capacity of laser drilling to effectively process hard and high-strength materials. Furthermore, it is critical to carefully determine the appropriate laser parameters to achieve the desired mechanical properties in laser-processed materials. Ongoing research is directed toward further understanding laser-material interactions and improving laser processing techniques. In brief, laser material processing technologies continue to play an important role in improving manufacturing processes and enhancing product quality.

Climate has continuously undergone change throughout history. Understanding this change contributes significantly to the determination of boundaries for different climate types. Climate classifications aim to differentiate various climate types and identify similar or different locations. This facilitates the sustainable use of local resources and the development of land use plans. Additionally, comprehending the impact of climate on property is crucial for its management and regulation, enabling a more organized approach to property utilization. In this context, various climate classification methods have been developed. These methods assist in determining local climate differences, tracking changes over time, and establishing boundaries suitable for different climate types. This study aims to create climate boundary maps for Burdur province using Köppen, Trewartha, de Martonne, Aydeniz, Erinç, and Thornthwaite methods. Within the scope of the study, data from 11 meteorological observation stations in Burdur province have been organized within a Geographic Information System (GIS) and classified into climate types. Finally, climate boundary maps representing the entire region were generated using the Kriging interpolation method based on the identified climate classification.

Maritime transportation is a keystone of the global economy, facilitating more than 90% of international trade by a fleet of nearly 90,000 vessels. However, the sector's reliance on fossil fuels brings with it significant environmental challenges, including greenhouse gas emissions, air and water pollution, and impacts on marine ecosystems. To address these issues and increase sustainability, there is a growing trend towards integrating renewable energy sources in the maritime sector. In particular, ocean-going vessels contribute more than 3% of global carbon dioxide emissions, while petroleum-based fuels emit significant amounts of nitrogen oxides and sulphur dioxide. In addition, shipping emissions are a major source of ambient air pollution in coastal areas. Projections indicate a potential 50-250% increase in carbon dioxide emissions from international shipping by 2050 if current trends continue. Renewable energy solutions such as wind, solar and nuclear power offer promising alternatives, with advances in technology increasing their efficiency and affordability. However, the transition to marine renewable energy requires overcoming technological barriers, infrastructure limitations and financial challenges. Despite these barriers, adopting renewable energy sources offers an applicable way to reduce the environmental impacts of shipping and ensure a sustainable future for the industry. This study focuses on renewable energy sources used in commercial ships and discusses alternative solutions such as wind, solar and nuclear energy. Furthermore, by highlighting the potential and advantages of renewable energy sources used on commercial ships, this study can be seen as an important step towards reducing environmental impacts and increasing sustainability in the maritime industry.

Disposable sterile needles are essential highly consumed medical tools. Medical needles are usually manufactured according to standardized protocols, which currently do not provide the specified minimum tolerance value of the penetration force which strongly depends on needle dimensions, needle cutting edge angle, and the type of the tissue surface to be penetrated. In the present study, experimental measurements were performed according to the ISO 7864 standard to investigate the needle-surface penetration effect via the experimental assessment of the influence of the needle dimensions, cutting edge angle, and three different types of biomedical textiles/artificial tissues (i.e. polyurethane (PU), polypropylene (PP), and artificial leather (AL)) on the penetration force. The results indicate that the smaller the needle's cutting-edge angle, the smaller the penetration force across the target tissue surface. An exponential decaying relationship has been found between the penetration force and the needle diameter/gauge. The results also show that PP provides similar results to other materials that are already included in ISO 7864, and it has a good potential to be accepted as a standardized biomedical textile.