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Role of Invertebrate Biological Origin in Chitin Nanocrystal’s Morphology, Chirality, and Self-Assembly
Get PDFThe mention of chitin often evokes the Bouligand structure, which is a unique twisted configuration featuring a uniaxial planar organization of fibers. Although a large number of studies focused on Arthropoda, the architecture of chitin in many other invertebrate phyla remains largely unexplored. Herein, we unveil the distinctive architectures of chitin in both Arthropoda and Bryozoa, offering a comparative analysis of the morphological properties of native fibers and chitin nanocrystals sourced from these divergent organisms. In stark contrast to the Bouligand architecture prevalent in Arthropoda, Bryozoa exhibits a unique spiderweb-like arrangement of nanobundle structures, exclusive to this animal group. Bryozoan chitin nanofibers have a diameter smaller than those found among arthropods. After acid hydrolysis, the bryozoan nanocrystals are shorter and have a diameter smaller than those from arthropods. Although the chitin nanocrystals formed the chiral nematic phase, in the current study with the applied methodology, this was not the case with chitin nanocrystals from the studied bryozoan species. The unique chitin nanoarchitecture observed in Bryozoa could serve as an inspiration to produce advanced materials. Their smaller chitin nanocrystals can serve as a potential alternative to those of arthropods.</p
Kansallisen energia- ja ilmastopolitiikan uudet toimet ja skenaariot (KEITO) – keskipitkän aikavälin vaikutusarviot
No full textKEITO-hankkeessa (Kansallisen energia- ja ilmastopolitiikan toimet ja skenaariot) on laadittu laskennallisia ja laadullisia skenaarioita keskipitkän ja pitkän aikavälin energia- ja ilmastopoliittisen päätöksenteon tueksi. Tässä raportissa on esitetty keskipitkän aikavälin laskennallisten skenaarioarvioiden tulokset ja lähinnä laadullisesti arvioitu vaikutuksia ympäristöön (I. SOVA). Tulokset palvelevat tausta-aineistona keskipitkän aikavälin ilmastosuunnitelmalle (KAISU) ja energia- ja ilmastostrategialle
Roles in Quantum Ecosystem opening innovation paths from technology to impacts
No full textThis paper studies the co-evolution of quantum technology ecosystems across three European regions: the Basque Country, Finland, and the Netherlands. By examining the roles of ecosystem actors during the innovation path from research to commercialization, the study aims to understand how these roles facilitate the emergence and development of quantum technologies. Using a comparative multi-case study approach, the study identifies key characteristics, collaborative dynamics, and challenges within these ecosystems. The findings highlight the importance of different ecosystem types, the significance of individual and organizational roles, and the need for dynamic interaction between technology innovation and market adoption. Practical implications are provided for academics, managers, and policymakers to enhance ecosystem development and competitiveness in the field of quantum technologies
Life Cycle Cost Framework for Enhancing Sustainable Manufacturing and Energy Efficiency of Production Assets
No full textThis study presents a life cycle cost (LCC) oriented framework aimed at enhancing sustainability and energy efficiency in manufacturing processes. It contributes to cost-effective energy management and energy efficiency optimization. The framework comprises various elements and modules to assess production assets’ LCC and demonstrate cost savings from energy optimization models and technologies. The main cost categories include capital expenditures (CAPEX), direct operational expenses (OPEX), and costs associated with productivity and material losses. The framework’s productivity and material loss cost module analyzes the life cycle cost impact of material losses due to waste and scrap, rework needed due to scrapped parts, and costs associated with machine downtime, idle time, and setup time. The iterative development, testing, and validation process ensured the framework’s robustness and practical applicability. The diversity of the manufacturing sector represented by the pilot companies ensured complementary and comparable cases. Future research phases will further employ the framework and the associated LCC tool for a second round of LCC assessments in the case study companies, comparing the current state (as-is) with the projected state after the implementation of the energy optimization solutions developed in the H2020 DENiM project (to-be).</p
The Effect of Elastic–Plastic Mismatch and Interface Proximity on the Fracture Toughness of Ti‐TiN Thin Films
No full textMagnetron sputtered titanium nitride (TiN) thin films are widely used as protective coatings due to their high hardness, but suffer from inherent brittleness and low fracture toughness, limiting their applicability. The multilayering of TiN films with metallic titanium (Ti) interlayers in the form of bilayer and trilayer architectures has been studied using microcantilever fracture tests. Plastic dissipation in the Ti layer is shown to lead to an increase in crack growth resistance. The effect of the elastic–plastic mismatch between the two materials on the crack driving force as well as the size of the fully developed plastic zone in Ti have been quantified in this work for the first time. It is shown that the plastic zone size of 250 nm in Ti layer improves the overall fracture resistance of the architecture by nearly ten times compared to the initiation fracture resistance in TiN, preventing catastrophic fracture of these multilayered films. These results will aid in physics informed design of optimized thickness of metallic interlayers in multilayered thin film architectures
Ash generation options for accelerated testing of marine diesel particulate filters:Technical Paper 138
No full textParticulate matter (PM) emissions, comprising black carbon (BC), organic fraction and sulfates, pose significant health risks, and the shipping sector substantially contributes to the PM levels, especially in coastal cities. Notably, air pollution remains the main environmental cause of premature deaths.Additionally to the health risks, BC emissions from shipping strengthen the global warming effects through deposition of BC on ice and snow. Practically, north of 70° latitude, shipping is the predominant source of BC emissions. The role of ship emissions is also increasing with the anticipated rise in commercial shipping, particularly in the Arctic. Since 2011, the International MaritimeOrganization (IMO) has worked on BC emissions from shipping.Diesel particulate filters (DPF) effectively reduce BC and PM emissions. Although DPF technology is well-established for vehicles and non-road mobile machinery, its adoption for marine diesel engines presents unique challenges related to the properties of marine fuels and engine oils (sulfur content,ash), and the regeneration process of the DPF. Ash plays a crucial role, as soot can be removed from the DPF through regeneration, but the accumulated ash cannot be cleaned simultaneously. To develop and verify the performance of marine DPFs, an accelerated ash accumulation method is necessary. We investigated four different ash generation methods: 1) a burner type ash generator, 2) a modern diesel engine, 3) a robust diesel generator, and 4) injection of high-ash engine oil into the engine’s intake air. Additionally, we refined a methodology to screen the ash content of engineexhaust
Voice pathology identification using mel spectrogram features and deep learning
Get PDFVoice pathology is very important in the identification of vocal disorders. Traditional methods of diagnosing voice disorders using voice pathology are expensive, time-consuming, and subjective. The study proposed the identification of normal and pathological voices using the Arabic Voice Pathology Database (AVPD). The study evaluated the performance of Support Vector Machine (SVM), hybrid deep learning, and transfer learning approaches for identifying normal and pathological voices. These models were trained using Mel spectrogram features extracted from the voice data from the AVPD. The transfer learning model outperformed with an accuracy of 96.88%, a precision of 0.96 and 0.98, a recall of 0.98 and 0.96 in the identification of normal and pathological voices, respectively. The transfer learning model showed an F1 score of 0.97 for both normal and pathological voices. The hybrid model showed an accuracy of 92.71% and superior performance in classification metrics to identify normal and pathological voices. The SVM model achieved an accuracy of 86.46% and showed low performance in classification metrics to identify normal and pathological voices. Deep learning models, particularly the transfer learning model, outperformed across all evaluation metrics. The proposed transfer learning model achieved a 1.53% increase in accuracy over state-of-the-art approaches in identifying voice disorders using voice pathology. The proposed solution has several applications in medical diagnosis, addressing issues associated with traditional approaches for identifying vocal disorders using voice pathology
Assessing the impact of climatic conditions and feeding systems on the quality of raw bovine milk in Spain
No full textThe dairy industry faces significant challenges from climate change, requiring a deeper understanding of how climatic factors influence raw milk composition and quality. The aim of this study was to evaluate the impact of climatic variables, such as temperature, solar radiation, and carbon dioxide levels, on raw milk parameters, including somatic cell count, protein percentage, fat, and total bacterial count. Selectivity ratio and Spearman rank correlation analyses identified key associations. This study analyzed data from 53 farms in northern Spain (2014 to 2019), using 2 feeding systems: Total Mixed Ration and Hand Feeding. Temperature and solar radiation negatively correlated with fat (r = -0.68, P < 0.05), protein (r = -0.71, P < 0.05), and dry lean percentages (r = -0.65, P < 0.05), while average temperature positively correlated with somatic cell count (r = 0.70, P < 0.05). Total bacterial count showed a negative correlation with carbon dioxide levels (r = -0.66, P < 0.05). Among the climatic variables, solar radiation, and carbon dioxide were highlighted as the most influential factors through selectivity ratio analysis. Additionally, Total Mixed Ration feeding systems appeared to support better metabolic adaptation, underscoring the importance of balanced diets in mitigating climate-induced stress. These findings emphasize the need for improved farm management practices to address climate change impacts on milk quality.</p
Investigation of DC Breakdown Properties of Low GWP Gas R404a and Its Mixtures with N<sub>2</sub>/CO<sub>2</sub> as an Alternative to SF<sub>6</sub>
No full textSulfur hexafluoride (SF6), an extraordinary gas insulation medium, must be replaced by environmentally friendly gas in electric equipment because of its high global warming potential (GWP). In this research work, the DC breakdown properties of R404a gas and its mixtures with N2 and CO2 are studied under a sphere–sphere electrode configuration and uniform field conditions. The GWP of R404a is 16% of SF6 and its liquefaction temperature is also in the suitable range for practical applications. Nitrogen and carbon dioxide are mixed with R404a to reduce its boiling point and GWP. Other important parameters such as the self-recoverability, liquefaction temperature, GWP, and synergistic effect of R404a/CO2 and R404a/N2 were also studied to complement the insulation performance and the results are comparable to other gas mixtures. As a result, it was found that both the mixtures containing 80% R404a and 20% N2 or 20% CO2 possess a breakdown strength of 0.83 times that of SF6. Mixtures containing an 80% concentration of R404a possess a GWP equal to only 15% of SF6. These properties make gaseous mixtures containing 80% R404a and 20% N2 or CO2 a suitable alternative to SF6 in medium-voltage gas-insulated equipment.</p