Gabriel Bogdan Carp

The continuous advancement of modern weaponry has intensified the pursuit of next-generation ballistic protection systems that integrate lightweight architectures, superior flexibility, and high energy absorption efficiency. This review provides a technological overview of current trends in the design, processing, and performance optimization of metallic, ceramic, polymeric, and composite materials for ballistic applications. Particular emphasis is placed on the role of advanced surface coatings and nanostructured interfaces as enabling technologies for improved impact resistance and multifunctionality. Conventional materials such as high-strength steels, alumina, silicon carbide, boron carbide, Kevlar^®, and ultra-high-molecular-weight polyethylene (UHMWPE) continue to dominate the field due to their outstanding mechanical properties; however, their intrinsic limitations have prompted a transition toward nanotechnology-assisted solutions. Functional coatings incorporating nanosilica, graphene and graphene oxide, carbon nanotubes (CNTs), and zinc oxide nanowires (ZnO NWs) have demonstrated significant enhancement in interfacial adhesion, inter-yarn friction, and energy dissipation. Moreover, multifunctional coatings such as CNT- and laser-induced graphene (LIG)-based layers integrate sensing capability, electromagnetic interference (EMI) shielding, and thermal stability, supporting the development of smart and adaptive protection platforms. By combining experimental evidence with computational modeling and materials informatics, this review highlights the technological impact of coating-assisted strategies in the evolution of lightweight, high-performance, and multifunctional ballistic armor systems for defense and civil protection.

Agriculture may hold the key to a sustainable future. By efficiently capturing atmospheric CO₂, we can simultaneously produce food, feed, biomass, and biofuels. For more eco-friendly soil processing practices, biofuels can replace diesel in agricultural machinery, significantly reducing the carbon footprint of crop production. Thus, biofuel production can be a sustainable solution for a future with a decreasing carbon footprint. This paper examines the possibility of replacing petroleum-based fuels with 100% biofuels to continue powering heavy-duty vehicles, where the use of electric vehicles is not the optimal solution. This study particularly focused on the operating scenario of heavy-duty engines under medium to high loads, typical of transport or soil processing in agriculture. Diesel was used as a benchmark, and each alternative, such as vegetable oil, methyl ester (B100), and methyl ester–ethanol blends (90B10E, 80B20E, and 70B30E), was tested individually. To find a sustainable fuel substitute, the goal was to identify a biofuel with a kinematic viscosity similar to that of diesel for a comparable spray process. Experimental results showed that an 80% methyl ester and 20% ethanol blend had a kinematic viscosity close to that of diesel. In addition to diesel, this blend resulted in a 48.6% reduction in exhaust gas opacity and a 6.54% lower specific fuel consumption (BSEC). The main aim of the tests was to find a 100% biofuel substitute without modifying the fuel injection systems of existing engines.

One of the environmental problems worldwide is the enormous number of surgical masks used during the COVID-19 pandemic due to the measures imposed by the World Health Organization on the mandatory use of masks in public spaces. The current study is a potential circular economy approach to recycling the surgical masks discarded into the environment during the COVID-19 pandemic for use in bituminous asphalt pavement. FTIR analysis showed that the surgical masks used were made from ethylene propylene diene monomer (EPDM) rubber modified with polypropylene. The effects of the addition of surgical masks in bituminous asphalt on the performance of the base course were demonstrated in this study. The morphology and elemental composition of the bituminous asphalt pavement samples with two ratios of surgical mask composition were investigated by SEM-EDX and the performance of the modified bituminous asphalt pavement was determined by Marshall stability, flow rate, solid–liquid ratio, apparent density, and water absorption. The study refers to the technological innovation of using surgical masks in the formulation of AB 31.5 bituminous asphalt base course, which brings tremendous benefits to the environment by reducing the damage caused by the COVID-19 pandemic.

The aim of the present work is to identify the expected nearshore and offshore impact of a marine energy farm that would be implemented in the coastal environment of Portugal. Several layouts of Wave Dragon devices were considered, the distance between each system being gradually adjusted. By processing 27–years of combined wave data coming from the European Space Agency and ERA5, the most relevant conditions have been identified. The centre of each farm layout was set to approximately 3.5 km from the coast, where a more significant attenuation of wave heights in the middle of the target area was noticed, which can go up to 16% in the case of extreme events. From the analysis of the longshore currents, it was noticed that even an arrow farm layout defined by five systems may have a significant impact, by changing the peak or by smoothing the currents profile. Wave energy is an emerging renewable sector that can also contribute tocoastal protection and, therefore, the Portuguese coast represents a suitable candidate for this type of project.

The use of sewage sludge in agriculture decreases the pressure on landfills. In Romania, massive investments have been made in wastewater treatment stations, which have resulted in the accumulation of important quantities of sewage sludge. The presence of these sewage sludges coincides with large areas of degraded agricultural land. The aim of the present article is to identify the best technological combinations meant to solve these problems simultaneously. Adapting the quality and parameters of the sludge to the specificity of the land solves the possible compatibility problems, thus reducing the impact on the environment. The physico-chemical characteristics of the fermented sludge were monitored and optimal solutions for their treatment were suggested so as to allow that the sludge could be used in agriculture according to the characteristics of the soils. The content of heavy metals in the sewage sludge was closely monitored because the use of sewage sludge as a fertilizer does not allow for any increases in the concentrations of these in soils. The article identifies those agricultural areas which are suitable for the use of sludge, as well as ways of correcting some parameters (e.g., pH), which allow the improvement of soil quality and obtained higher agricultural production.