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By leveraging the principles of electromagnetic theory and materials science, the characteristics of dielectric polymer composites can be optimized, eliminating repetitive trial‐and‐error in their application as electromagnetic absorbers (EMAs). Herein, a systematic framework for optimizing the thickness and composition of double‐layer EMAs is proposed, using a combination of transmission line, Debye relaxation, and Maxwell–Garnett theories. Following theoretical optimization, a double‐layered electrospun EMA is fabricated, which comprises a ≈1.17 mm thick matrix of styrene–butadiene–styrene (SBS) decorated with MXene on its fibrous structure. The second SBS layer, with a thickness of ≈0.52 mm, incorporates a hybrid of MXene and graphene nanoribbons (GNR) as conductive additives. The EMA exhibits durable electrical performance after 2000 tensile cycles, owing to the surface chemistry engineering and the novel in situ assembly technique. It is capable of shielding 99.9% of the incident wave and >80% absorptivity (A) over almost the entire Ku‐band. The EMA also exhibits desirable mechanical characteristics, such as >300% stretchability and full twist and wrinkle recoveries, making it an excellent choice for protective attire applications. Additionally, the introduced approach provides solutions for the advancement of tailorable polymer composite EMAs, with respect to specific criteria of the target wave frequency, effective absorption bandwidth, and absorption levels. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the influence of wax, polyethylene film (19 μm thickness) and storage time on the quantitative and qualitative characteristics and shelf life of ‘Kinnow’ mandarin fruit (Citrus reticulata Blanco cv. ‘Kinnow’) stored at 5°C for 90 days. The mandarins were analyzed for physicochemical characters such as weight loss, weight of fruit, flesh, pulp, juice and peel, as well as total soluble solids (TSS) content, titratable acidity (TA), and pH. Polyethylene film wrapping reduced fresh weight loss and resulted in the highest fruit weight at the end of the 90-day cold storage period. No significant differences were found among coating treatments in pH, TSS, TA content and TSS/TA. The results revealed an increasing trend in TSS and TSS/TA during storage. It is recommended to use polyethylene coating on ‘Kinnow’ mandarins to prevent weight loss and preserve quality during storage at low temperature (5°C) up to 90 days.

The decisions made during product development (PD) lock in 70-80 % of total product cost, and the quality of the product is also largely fixed. Therefore, these decisions have a great influence on product life cycle cost, quality, and sustainability. To improve such decisions, designers need to make high-level trade-offs among various criteria to see their effects. Therefore, developing a model to support trade-offs for sustainable product development is a significant concern for designers. This research attempts to consider sustainability, quality, and cost simultaneously to make trade-offs between environmental issues and other customer requirements to select the best design specifications on their basis. Sustainability is considered as a customer requirement, which then is translated into design specifications. In this study, sustainable design is treated as an optimization problem to maximize value-added activities while minimizing environmental effects. Multi-attribute utility theory is utilized in order to formulate combination of the customer's opinions and make a trade-off between different groups of customer requirements in the final model. An optimization model is then defined to model sustainability, quality, and cost in the product development process in order to find the optimum level of their combination thereof. By using this model, designers need not select between different solutions since they can find the optimal solution. A case study is illustrated and the results are discussed. [ABSTRACT FROM AUTHOR]

Electromagnetic pollution presents growing challenges due to the rapid expansion of portable electronic and communication systems, necessitating lightweight materials with superior shielding capabilities. While prior studies focused on enhancing electromagnetic interference (EMI) shielding effectiveness (SE), less attention is given to absorption-dominant shielding mechanisms, which mitigate secondary pollution. By leveraging material science and engineering design, a layered structure is developed comprising rGOnR/MXene-PDMS nanocomposite and a MXene film, demonstrating exceptional EMI shielding and ultra-high electromagnetic wave absorption. The 3D interconnected network of the nanocomposite, with lower conductivity (10 -3 -10 -2 S/cm), facilitates a tuned impedance matching layer with effective dielectric permittivity, and high attenuation capability through conduction loss, polarization loss at heterogeneous interfaces, and multiple scattering and reflections. Additionally, the higher conductivity MXene layer exhibits superior SE, reflecting passed electromagnetic waves back to the nanocomposite for further attenuation due to a π/2 phase shift between incident and back-surface reflected electromagnetic waves. The synergistic effect of the layered structures markedly enhances total SE to 54.1 dB over the K u -band at a 2.5 mm thickness. Furthermore, the study investigates the impact of hybridized layered structure on reducing the minimum required thickness to achieve a peak absorption (A) power of 0.88 at a 2.5 mm thickness., (© 2024 The Author(s). Small published by Wiley‐VCH GmbH.)