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The margin between a deficient (∼0.02mg day^‐1), an adequate (∼0.2mg day^‐1) and toxic (∼2.4mg day^‐1) intake of selenium is quite narrow, and this study sought to establish whether fruits grown in the Jordan Valley were safe for consumers, and yet capable of supplying a likely dietary requirement for the mineral. The mean levels of soil selenium were 0.64, 0.74 and 0.63mg kg^–1 in three different growing regions of the Valley, while the highest levels in citrus fruits were 2.5mg kg^–1 in clementines (Citrus mitis) and 3.31mg kg^–1 in the bomali (Citrus paradisi). As the latter values were on a dry weight basis, the risk of selenosis would appear to be minimal but, equally important, deficiency diseases should not be manifest either.

The net power delivered to the surface of parts (i.e. the actual heat flux) is a key parameter in the laser melting process and its exact control has a great impact on the numerical solutions. In this paper, the impact of laser additive manufacturing parameters including laser power, scanning speed and powder injection rate on thermal efficiency, net power delivered to the part and power loss due to powder flow has been investigated.

The response surface method was applied to measure the net laser power in laser deposited Inconel 718 using k-type thermocouples. The temperature history obtained by thermocouples was used to calculate the net power delivered by inverse analysis method. The applied model is Rosenthal's optimized model, in which all the thermal properties of the material are considered to vary with temperature.

The results indicated that the thermal efficiency, power delivered to the part and power loss can be optimized simultaneously at laser power of 400 W, scanning speed of 2 mm/s and powder injection rate of 200 mg/s. The microstructure analysis indicated that a high-quality sample without microstructural defects was formed under optimal condition of parameters. Moreover, the primary dendrite arm spacing for the optimal sample was higher than that obtained for other samples.

The novelty of this research summarized as follows: Prediction of the thermal efficiency and power loss during the laser metal deposition of Inconel 718 superalloy using the inverse analysis. Finding the optimal values of thermal efficiency, power delivered to the surface and power loss in the laser metal deposition of Inconel 718 superalloy. Investigating the effect of laser power, powder injection rate and scanning speed on the thermal efficiency and power loss of Inconel 718 superalloy during the laser metal deposition.

Although electric vehicles (EVs) offer promising solutions for reducing transport emissions, several obstacles hinder their adoption, and supply chain (SC) stakeholders must systematically identify and address these challenges. Prior research has explored barriers to EV adoption but lacks a global focus on last-mile delivery (LMD). Our study aims to fill this gap, providing a foundation for future research and aiding organizational shifts towards sustainable transportation.

Our study identifies 21 critical barriers to EV deployment in LMDs, validated through a quantitative survey involving 157 SC experts. The survey data are analysed using Exploratory Factor Analysis (EFA), which identifies four distinct dimensions encapsulating the identified barriers. Based on consultations with five experts, the Analytical Hierarchy Process (AHP) ranks these dimensions and individual impediments globally.

The study finds “Energy and Infrastructure Barriers” and “Financial and Resource Barriers” to be the most significant hindrances. Noteworthy individual barriers include the absence of fast-charging stations, insufficient electricity provision and the need for investment in Power Grid upgrades.

This research contributes to the existing literature by offering a robust methodology for classifying and ranking EV adoption barriers through EFA and AHP. It thus provides a globally applicable framework for stakeholders to devise targeted strategies for overcoming these barriers.