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Monitoring and assessment of potentially hazardous particles in high-risk workplaces in the production of Ni-Cd batteries
(Springer Nature, 2026) Tokarčíková, Michaela; Bernatíková, Šárka; Rössner ml., Pavel, Pavel; Vrbová, Kristýna; Šíma, Michal; Gabor, Roman; Běčák, Petr; Seidlerová, Jana
The manufacture of Ni-Cd batteries involves the risk of contact with and inhalation of dust particles containing heavy metals, including potential carcinogens. Three workplaces were selected that appeared to pose the greatest risk to workers in terms of exposure to heavy metal (nickel and cadmium) dust generated during the production and handling of nickel-cadmium plates. Although the limits for dust and carcinogens and mutagens are very strict, they are gradually being tightened. Therefore, the main motivation was to find the source of the highest amounts of respirable particles, determine the size of the particles, the composition of the fraction and evaluated potential toxicity of particles captured on the filters. This will help to propose additional measures to minimise concentrations of potentially carcinogenic particles in the working environment. The chemical analysis, particle size distribution, metal content and cytotoxicity of the particles trapped on the filters were investigated. While the concentration of heavy metals was well below the permissible exposure limits, the extracts obtained from the sampled filters had a significant effect on cytotoxicity, particularly those containing lower concentrations of particles.
A catalytic approach to the valorization of polyesters and biogenic waste for the production of amines
(Elsevier, 2026) Poovan, Fairoosa; Jagadeesh, Rajenahally V.; Beller, Matthias
Despite the numerous applications of polymers in human life, their excessive use has caused serious environmental hazards. Among polymer recycling methods, chemical recycling offers a streamlined approach to polymer degradation by enabling depolymerization without compromising functionality. Specifically, hydrogenolysis of polymers, a depolymerization technique that utilizes hydrogen to cleave bonds, has emerged as a powerful strategy for depolymerization, facilitating the upcycling of plastics into high-value chemicals. Previous research in this area has predominantly focused on noble metal catalysts, while the potential of base metals remains unexplored. Herein, we propose a cobalt-based hydrogenative amination approach for the depolymerization of polyesters to versatile diamines as well as amino alcohols. This strategy can also be applied to the one-pot synthesis of fatty amines from used cooking oil. The current system opens new avenues for the upcycling of waste into valuable amines, providing a viable solution to plastic pollution and a way to utilize waste as a resource.
Three-dimensional surface metrology analysis of cryogenically machined additively manufactured aluminium alloys
(Elsevier, 2026) Gupta, Munish Kumar
Surface roughness and topography play a critical role in determining the performance and reliability of additively manufactured (AM) aluminium alloys, particularly after post-processing by machining. This study presents a comprehensive three-dimensional surface metrology analysis of machined additively manufactured Al-Si-10Mg aluminum alloy under varying cooling conditions, including dry, minimum quantity lubrication (MQL), air, and cryogenic CO2 environments. Surface characterization was performed using a Sensofar microscope operating in interferometry mode to acquire high-resolution 3D surface data. A full set of amplitude, spatial, and hybrid roughness parameters was evaluated, along with material ratio and volume parameters for functional assessment. The results show that at cutting speeds of 230–270 m/min, the average roughness (Sa) remained above 0.30 μm, while the root mean square roughness (Sq) ranged from 0.45 to 0.50 μm, indicating a smooth and periodic surface trend. Cryogenic cooling produced the most refined surfaces, with Sz values of 3.3–3.5 μm at 150–230 m/min and a moderate increase to 3.9–4.0 μm at 310 m/min. The results also show that the surface formation mechanisms of AM AlSi10Mg are significantly influenced by cooling conditions, leading to variations in texture orientation, roughness distribution, and material properties. In addition, the enhanced cooling conditions yielded improved surface integrity of AM AlSi10Mg, as measured by interferometry, reflected in lower roughness values and optimized core and valley volume parameters, which are beneficial for wear and fatigue related applications.
Optimizing multi-step kinetic schemes for biomass pyrolysis in bioenergy production using multi-objective genetic algorithm: Transitioning from thermally thin to thermally thick regime
(Elsevier, 2026) Vasudev, Vikul; Tahir, Mudassir Hussain; Ram, Shri; Duan, Yanjun; Adamec, Tomáš; Najser, Tomáš
This study aims to optimize multi-step kinetic models for biomass pyrolysis to enhance bioenergy production. Utilizing three representative biomass types, i.e., Cunninghamia lanceolata (forestry-derived), rice straw (agricultural-derived), and green algae (aquatic-derived), thermogravimetric analysis was conducted across temperatures from 150 to 600 degrees C at heating rates of 5, 20, 30, and 40 degrees C/min. Three kinetic schemes with three, four, and nine reactions were parameterized using a parallelized multi-objective genetic algorithm fitting the model simultaneously to all heating rates. The four-reaction scheme achieved the highest fit quality (R-2 > 0.97 for all feedstocks), while the nine-reaction model provided detailed mechanistic insights but showed reduced accuracy for green algae (R-2 as low as 0.81). Coupling these kinetic models with a 2D heat transfer model of a thermally thick biomass particle revealed distinct thermal gradients and reaction front behaviors for each scheme, including average front propagation speeds of 0.19 mm/min and core conversion times between 27 and 34 min. The most complex scheme exhibited the fastest core conversion rate (up to 23 % faster), broadest and most diffuse reaction front, and greater char production. Whereas, simpler schemes produced sharper, localized fronts with slower conversion. This integrated experimental-computational approach quantitatively characterizes pyrolysis kinetics and thermal dynamics, advancing model development for optimized industrial bioenergy applications.
Assessing climate risk on the European financial system: a multi-scenario Analysis
(Springer Nature, 2026) Giacchetta, Gianandrea; Giacometti, Rosella; Torri, Gabriele
This paper investigates the impact of climate risk on the stability of the European financial system, with a particular focus on both transition and physical risk dimensions. Given the long-term and uncertain nature of climate-related risks, traditional econometric methods often fall short in capturing their systemic implications. To address this challenge, we develop a scenario-based framework grounded in realistic projections consistent to the theoretical framework of the Network for Greening the Financial System ("NGFS"), encompassing three climate pathways: orderly transition, disorderly transition, and hot house world. We model the relationship between climate risk drivers, European companies, and the financial system using vine copulas, enabling a flexible representation of complex dependencies. The effects of these scenarios on financial institutions are evaluated through key risk metrics (expected return, value at risk, and expected shortfall) conditioned on each climate scenario. Our results offer insights into how climate transition risks propagate through the financial system, with practical implications for financial stability assessment and systemic risk management. The primary contribution lies in integrating both transition and physical climate risks into a coherent and tractable risk assessment framework, offering valuable tools for policymakers, regulators, and financial practitioners. Results show a significant dependence of European financial system to brown companies and, thus, sizable losses in the disorderly transition scenario.