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Electrochemical polarization behavior and superelastic properties of a Fe–Mn–Al–Ni–Cr shape memory alloy
(2022-10-22)
The present study investigates the corrosion behavior of a Fe–Mn–Al–Ni–Cr shape memory alloy in a 5.0 wt% NaCl solution in combination with the functional properties. In a single crystalline condition, the investigated alloy shows a superior superelastic response with a maximum recovery strain of 5.2%. Furthermore, the results of the potentiodynamic polarization and impedance spectroscopy show that the addition of chromium generally improves corrosion resistance by increasing the resistance to localized corrosion. ...
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Technoeconomic analysis of standalone hybrid renewable energy systems for telecommunication sector under different climatic conditions in Saudi Arabia
(2024-04-05)
Reliance on conventional fossil fuels to fulfil the extensively increasing energy demands due to industrial development is becoming a financial burden and a huge source of global warming. Saudi Arabia, possessing nearly 15% of the world's oil reserves, confronts an intricate scenario where approximately 53% of government revenue is oil-dependent, rendering it the 11th largest global emitter of carbon gases. This proclivity underscores the urgent need for transitioning towards renewable energy sources to alleviate ...
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Combined Funnel, Concentrator, and Particle Valve Functional Element for Magnetophoretic Bead Transport Based on Engineered Magnetic Domain Patterns
(2023-10-27)
Controlled actuation of superparamagnetic beads (SPBs) within a microfluidic environment using tailored dynamic magnetic field landscapes (MFLs) is a potent approach for the realization of point-of-care diagnostics within Lab-on-a-chip (LOC) systems. Making use of an engineered magnetic domain pattern as the MFL source, a functional LOC-element with combined magnetophoretic “funnel”, concentrator, and “valve” functions for micron-sized SPBs is presented. A parallel-stripe domain pattern design with periodically ...
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Differences in enteric methane emissions across four dairy production systems in the urbanizing environment of an Indian megacity
(2024-01-17)
Low- and middle-income countries (LMICs) are rapidly urbanizing, leading to a high demand for high-quality animal products. Production increase is seen as a key to meeting this demand and reducing the global environmental impact of low-yielding dairy production system (DPS) often found in LMICs. Therefore, the present study assesses the relationship between enteric methane emissions and different dairy production strategies, taking DPS in the rural–urban interface of Bengaluru, an Indian megacity, as a case study. ...
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UVC Irradiation as a Surface Treatment of Polycarbonate to Generate Adhesion to Liquid Silicone Rubber in an Overmolding Process
(2024-04-18)
This study investigates the adhesion properties of polycarbonate (PC) and liquid silicone rubbers (LSR) through surface activation using ultraviolet C (UVC) radiation. While self-adhesive LSRs adhere easily to certain thermoplastic composites such as polybutylene terephthalate (PBT) and polyamides (PAs), bonding to PC typically requires surface treatment due to the lack of compatible functional groups. Previous methods like plasma or flame treatment have been effective, but the use of UVC radiation for surface ...
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Towards collaborative planning: deliberative knowledge utilisation and conflict resolution in urban regeneration in South China
(2024-03-22)
Urban regeneration in post-reform China has become a fertile ground for the transition towards collaborative planning, which serves as a powerful tool for managing conflicts and addressing complex urban challenges. This article aims to delve into the micro-level processes that underpin the emergence of collaborative planning in practical urban regeneration projects in China. By shedding light on these micro-level processes of conflict resolution, we aim to provide a deeper understanding of how collaborative planning ...
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Labour relations and working conditions of workers on smallholder cocoa farms in Ghana
(2023-06-16)
The millions of farm workers in the Global South are an important resource for smallholder producers. However, research on their labour organisation is limited. This article focuses on smallholder farm workers in Ghana’s cocoa sector, drawing on insights from qualitative interviews and the concept of bargaining power. We review the labour relations and working conditions of two historical and informally identified labour supply setups (LSSs) in Ghana’s cocoa sector, namely, hired labour and Abusa, a form of ...
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On the Influence of Surface Hardening Treatments on Microstructure Evolution and Residual Stress in Microalloyed Medium Carbon Steel
(2020-06-09)
Tailoring surface properties is a key to superior performance of components subjected to fatigue loadings in application. Process–microstructure–property relationships have to be established to allow for optimization of techniques employed for surface treatments such as deep rolling and induction hardening. Although both techniques are employed widely in industrial application, studies examining microstructure evolution and residual stress states for a single material in a comparative manner are missing. Amongst ...
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Influence of Microstructure and Defects on Mechanical Properties of AISI H13 Manufactured by Electron Beam Powder Bed Fusion
(2021-08-04)
Electron beam powder bed fusion (E-PBF) is a well-known additive manufacturing process. Components are realized based on layer-by-layer melting of metal powder. Due to the high degree of design freedom, additive manufacturing came into focus of tooling industry, especially for tools with sophisticated internal cooling channels. The present work focuses on the relationships between processing, microstructure evolution, chemical composition and mechanical properties of a high alloyed tool steel AISI H13 (1.2344, ...
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Evaluation of extremely steep residual stress gradients based on a combined approach using laboratory-scale equipment
(2021-11-30)
Surface treatments characterized by rapid heating and cooling (e.g. laser hardening) can induce very steep residual stress gradients in the direct vicinity of the area being treated. These gradients cannot be characterized with sufficient accuracy by means of the classical sin2Ψ approach applying angle-dispersive X-ray diffraction. This can be mainly attributed to limitations of the material removal method. In order to resolve residual stress gradients in these regions without affecting the residual stress equilibrium, ...