MATEC Web of Conferences, open access proceedings in Materials science, Engineering and Chemistry

External and internal microclimatic conditions, biodeterioration, anthropogenic factors, etc, influence the natural stone support for artifacts and built heritage. Based on this fact, the present study explores the effectiveness of nano-TiO₂ in preserving and enhancing the durability of natural stone used in the façades of heritage buildings, focusing on the Markovits-Mathéser House in Oradea Municipality, Romania. The investigation involved treating rock samples (fossiliferous limestone) with 2% and 5% nano-TiO₂ solutions and subjecting them to simulated extreme climatic conditions for the analyzed area in a controlled climatic chamber for six months. The treated samples demonstrated a significantly higher compressive strength than untreated benchmarks. SEM analyses confirmed that nano-TiO₂ formed a protective layer, filling micro-cracks and pores, thereby enhancing the stone’s resistance to environmental stressors. The study also found that the nanoparticle coating maintained its integrity under extreme temperature and humidity variations, with only a slight decrease in surface coverage. These findings suggest that nano-TiO₂ coatings significantly improve heritage building materials’ mechanical properties and longevity. However, the study highlights the importance of careful application and long-term evaluation to ensure environmental and health safety. Overall, nano-TiO₂ presents a promising solution for the conservation of cultural heritage, offering enhanced durability and protection against climatic and environmental challenges. Further research is recommended to optimize application workflow and formulations for broader and more effective use in heritage conservation.

Indoor air quality is paramount for the health and well-being of individuals, especially in enclosed spaces like office buildings, schools, hospitals, and homes where people spend a significant amount of time. Ensuring good indoor air quality is not only essential for reducing symptoms such as headaches, eye and respiratory irritation, fatigue, and difficulty in concentration, but it is also a key component of sustainable building practices aimed at promoting long-term health and environmental balance. This study aims to explore the impact of the microclimate and fungal microbiota on the health and cognitive performance of occupants in a university classroom, which is part of a cultural heritage building. The research delves into various microclimatic parameters, including temperature, relative humidity, CO₂, volatile organic compounds, O₂, and particulate matters (PM_2.5 and PM₁₀), to understand their influence on the development of microbiota and the manifestation of symptoms associated with Sick Building Syndrome. Over the course of a year-long investigation, microbiological samples were collected, revealing the presence of 19 fungal species, with Cladosporium, Alternaria, and Aureobasidium being the most prevalent genera. These species were found to thrive in an environment characterized by inadequate ventilation, posing potential health risks to occupants, such as allergic reactions and respiratory infections. Microclimatic parameter values such as mean temperature of 22.9 °C and mean relative humidity of 38.5% indicated moderate conditions for fungal proliferation, but occasional high levels of PM_2.5 and CO₂ indicated periods of poor indoor air quality, negatively influencing the comfort and health of the occupants. The questionnaires completed by 190 students showed that 51.5% reported headaches, 44.2% frequent sneezing, and 43.7% severe fatigue, linking these symptoms to increased levels of CO₂ and PM_2.5. The novelty of the study lies in the integrated approach to indoor air quality assessment in a heritage educational building, highlighting the need for improved ventilation and air management to enhance health and cognitive performance, while emphasizing sustainable indoor environment management that balances occupant well-being with the preservation of cultural heritage.

In this paper, a brief overview is presented, resulting from a recent literature review of some representative books or papers regarding various research on different types of parallel robots, parallel kinematic machines, or hybrid parallel mechanisms. Starting from a short introduction regarding the motivation and necessity of the emergence of such parallel mechanisms, some basic terms are presented, in the context of founding the existence of several terminologies for certain specific expressions of this subject, as well as different definitions for them. Then, after a short presentation of the advantages and disadvantages of the parallel robots, compared to serial ones, and of the parallel kinematic mechanisms compared to the conventional machine tools, some publications related to kinematics, dynamics, modeling and simulation of these types of mechanisms are highlighted. This research is realized in order to identify a solution that will be the basis for the development of a prototype, both virtual and experimental, for such mechatronic system.

In this study, high-performance gloves were developed from core–sheath yarn. Different materials were used in the core, while Kevlar fibers were used in the sheath. The filaments used in the core included glass, ultra-high-molecular-weight polyethylene (UHMWPE), and stainless steel filaments with 100D and 200D linear densities. Seamless gloves were developed from these yarns with varying characteristics to observe their effect on the performance of seamless gloves. The factors examined were the areal density (GSM) of the gloves, linear density of sheath fibers, core material, and plied structure. The mechanical behavior of the gloves was evaluated by different tests such as blade cut resistance, coupe cut resistance, tear resistance, and puncture resistance. The results demonstrated that the sheath fiber characteristics, core material type, yarn’s plied structure, and fabric’s areal density are statistically significant factors affecting the properties of gloves in relation to mechanical risk. The selection of appropriate levels of these parameters is crucial for better achievement of desired properties in workwear protection applications.

This paper presents a short part of a larger research and consists in the investigation of the compression behavior of samples printed on two 3D printers, one Delta and one Cartesian, from three types of the commonly used materials, Polylactic acid (PLA), Carbon fiber PLA (CF-PLA), and Polyethylene terephthalate glycol (PETG). After a specific introduction regarding the subject, the printing parameters used for printing the samples are exposed, in a table, followed by a paragraph on the compression testing, both with general and particular information, on this case. The research being under development, the first set of results obtained is presented, further tests and analysis following in order to realize a comprehensive characterization of the 3D printed materials’ behavior.