Abstract
The increasing awareness on climate issues in the built environment places a greater responsibility on the different actors to map the building emissions, reduce and optimise the use of ...materials, and thereby lower the environmental footprint. With several countries enforcing legally binding CO
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limits to assess and benchmark the negative environmental side effects from buildings using the LCA method, it is presumable that practitioners from the industry will look for higher availability of data found from Environmental Product Declarations (EPDs). As the availability of data more than likely will increase drastically over the years, the study provides an extensive look into the world of digitalised EPDs, and how to use the format to extract a comprehensive number of EPD data. The extraction of data from the ECO Platform leads to a total of 1478 entities, and when adding EPDs from EPD Denmark this study scrutinises 1644 EPDs in total, from 4 EPD Program Operators (EPD-POs). The extraction process highlights the need for transparency and more mutual agreements in the documentation methods. Further, the study scratches the surface of the revised European EPD Standard EN15804, and what the changes and the transition will mean for the applicability and transparency in the building sector and for LCA models when the majority of emissions from GWP will increase.
A study on retrospective dosimetry was performed using electronic personal dosimeters (EPDs) for reconstructing doses received by radiographic testing workers. The dosimetric properties of the ...thermoluminescence (TL) peak in the temperature range of 100–200 °C were investigated by measuring the TL of the resistors extracted from the EPDs in a darkroom environment. Results showed that this TL peak exhibited optimal dosimetric properties, with a minimum detectable dose as low as 13 mGy. To calculate the absorbed dose using the resistors, a simplified single aliquot regenerative (SAR) dose method using the TL peak was employed. The zero dose of the commercial EPD (model CLOVER) was determined to be 58 ± 72 mGy through the random selection of six EPDs. Additionally, a dose overestimation correction factor for compensating rapid sensitivity changes after TL measurement of the natural sample was calculated as 1.73 ± 0.09. Furthermore, it was observed that the TL signal faded exponentially to approximately 60% over a period of 12 weeks. Subsequently, retrospective dosimetry was performed by irradiating EPDs with a standard gamma ray dose of 1 Gy. The radiation exposure dose calculated from the TL peak of the resistors was found to be approximately 10% lower. These findings showed that the retrospective dosimetry with EPD can be utilized for accurately estimating the radiation exposure dose.
•Retrospective dosimetry was performed using resistors in electronic personal dosimeters.•The thermoluminescence dosimetric properties of resistors were investigated.•Electronic personal dosimeters are potentially suitable for retrospective dosimetry.
In this study, multi-structured coatings of biocompatible and antibacterial materials on a 316L stainless steel (SS) implant have been electrophoretically deposited for orthopedic applications. Two ...layers of composite coatings have been deposited; the first layer of composite coating biopolymer layer consists of (chitosan with Gelatin) and the second composite coating layer of bio-ceramic comprises Hydroxyapatite with chitosan. The first layer was deposited at (3 g/L concentration of Gelatin, 20 voltage, and 3 min and 0.5 g/L chitosan) parameters, and the second layer was deposited at (6 g/L, 40 voltage, 1 min, and 0.5 g/L chitosan) parameters. In this study, the stability of the suspension was evaluated using the Zeta potential test, which manifested good stability. The adhesion strength between the composite coatings' first layer and the 316L stainless steel substrate, as well as between the coating layers themselves, was determined using the Tape test, and the removal area for the first layer was 8.06% while for the second layer was 6.01%. The wettability test elucidated for the 316L stainless steel and first coating layer and the second coating layer, the second composite coating layer became super hydrophilic, and a very high wettability was exhibited with multilayer coating. Scanning electron microscopy showed that the surface's topology revealed a homogenous and defect-free composite coating. The result of the antibacterial efficiency of the 316L SS substrate improved as the number of coating composite layers increased, and the resistance to corrosion of 316L SS enhanced as the number of coating composite layers increased.
We fabricated an additive-free MAX(Ti 3 AlC 2 ) phase Li-ion battery (LIB) electrode using the electrophoretic deposition (EPD) method. In this study, MAX, a precursor of MXene, which has recently ...been receiving great attention as a negative electrode material for LIBs, was manufactured as a coin cell through EPD rather than the conventional slurry system. We excluded the effect of additives on the electrochemical performance, enabling evaluation of the intrinsic electrochemical properties related to battery charging and discharging. As a result, the battery using MAX as an anode material showed a large specific capacity of 148.2 mAh/g in the first discharge and superior cycle stability. Enhanced cycle stability and reversible electrochemical reactions were attributed to activation of faradaic and non-faradaic behavior, i.e., pseudo-capacitive behavior, caused by delamination of the MAX(Ti 3 AlC 2 ) into MXene (Ti 3 C 2 ). This was confirmed by the decrease in the charge transfer resistance and the increase in total capacitance at the interface, using electrochemical impedance spectroscopy and cyclic voltammetry measurements. In addition, the activation of pseudocapacitive behavior was confirmed by the change in kinetic mechanism, as evidenced from a significant increase in the Li ion diffusivity with cycles. These results demonstrate that MAX(Ti 3 AlC 2 ) is promising as an anode material for LIBs and at the same time shows potential for tuning electrochemical properties through the electrochemical delamination process.
(Received 1 July, 2022; Accepted 8 November, 2022)
In recent years, it has become essential to consider the total carbon footprint of a construction project. Commonly, the question has been: ’What is the best material to be used in this context?’ In ...this paper we argue that this question is incomplete, not taking the complexity of design choices into consideration. This paper intends to share light on how to analyse some factors that influence the construction of buildings in order to contribute to climate change mitigation, taking this complexity into consideration. Calculation of fossil greenhouse gas (GHG) emissions for two load-bearing structures for office buildings in 4, 8 and 16 storeys with equal functional requirements; e.g. load bearing capacity, acoustic performance, fire resistance and adaptability are addressed. The main materials for the load-bearing structures are cross laminated timber (CLT) elements and precast concrete elements respectively. The result show that one cannot on a general basis conclude that either type of load-bearing structure cause less fossil GHG emissions. It is always important to consider the building design, functionality as well as external conditions such as location when considering different load-bearing structure materials.
Because of its cost-effectiveness, good uniformity, fast deposition rate and simplicity, electrophoretic deposition (EPD) has been widely used to deposit various metal oxide films for different ...applications. As with other coating fabrication processes, the deposition rate and film quality are two crucial criteria to evaluate the effectiveness and suitability of EPD. In this review, we summarize the parameters and discuss the dynamic processes influencing the deposition behavior of ionically charged metal oxide particles. Special focus is also given to the methods to improve the film quality. In addition, the application of EPD in the fabrication of solid oxide fuel cells (SOFCs) is summarized.
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•The deposition behavior of metal oxides is influenced by parameters related to the suspension and the operation.•The increasing resistance is mainly resulted from the formation of an ion depletion zone.•The modulated electric fields appear to be particularly promising for the formation of dense green bodies.•This review also summarizes the application of EPD to the fabrication of SOFCs.
The use of environmental product declarations (EPDs) of concrete and other construction materials is gaining momentum. EPDs should enable an informed selection of products with a lower environmental ...footprint; hence, the issue of EPD comparability is highly relevant. In this paper, we identified and discussed the present shortcomings and future opportunities that can promote a meaningful EPD comparison for concrete products. Based on the published EPDs, we suggest a more comprehensive water consumption accounting, as the batching water is commonly underestimated. A set of performance metrics required to be specified for concrete are proposed to be included in the product category rules. An effort to develop a procedure for the regular calibration of existing tools with identical calculation databases and methods can produce outcomes that differ by 1–19%. The incorporation of prescriptive and consistently implemented life cycle inventory can minimize the calculation noise. The incorporation of uncertainty and variability as well as a supply-chain-specific EPD creation can help move toward a robust comparison based on the existing data in EPDs.
In this work, the synergistic effect of polyaniline (PANI) and Ce cations was utilized to develop a graphene oxide (GO) electrophoretic deposition (EPD) green epoxy (EP) coating with a physical ...barrier and corrosion inhibition. PANI and Ce cation not only form a protective layer with inhibition but also convert the negative charge of GO to a positive charge, thus satisfying the conditions of cathodic electrophoretic deposition (C-EPD). Anti-corrosion test results showed that the GO/PANI/Ce(NO3)3 (GPC)/EP composite coating has the highest impedance, with the impedance modulus at day 35 three orders of magnitude higher than that of the neat EP coating. The passivation film generated by the GPC inhibits large corrosion extensions; it produces a significant self-healing effect, as evidenced by the corrosion morphology, the XPS analysis, and the stable value of the impedance modulus. This work provides a new strategy for manufacturing high-performance electrophoretic epoxy coatings with self-healing properties.
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TiO2 Nanoparticle/Trimethoxy(propyl)silane (TMPSi) ceramic composite coating was deposited on 316L steel using a one-step electrophoretic deposition (EPD) method. Silane coupling agent (TMPSi) was ...added to the EPD bath in different concentrations (from 0.5 to 15 vol %) to decrease the surface energy of the deposited coating. TiO2 coating is hydrophilic whereas by adding varying concentrations of TMPSi, the obtained nanocomposite coating showed much better hydrophobicity. Surface wettability was measured by water contact angle (WCA) and sliding angle (SA) tests. Moreover, the effect of TMPSi concentration was determined by comparing the WCA and SA values. Surface morphology was studied through Field Emission Scanning Electron Microscopy (FESEM), and the presence of micro/nano meter roughness on the surface was confirmed. The distribution of elements were investigated by EDS analysis in which their uniform dispersion was observed. Corrosion behavior of 316L samples before and after the coating process was studied by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) tests in 3.5 wt % NaCl solution. The polarization curve proved that the superhydrophobic ceramic nanocomposite coatings (WCA = 168° and SA = 3.1°) were able to decrease the corrosion rate of bare 316L (from 12.180 to 5.621 (μm per year)).
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•A superhydrophobic nanocomposite coating was deposited on the 316L.•A one-step process was used.•The superhydrophobic nanocomposite coating improved the corrosion resistance of 316L effectively.•The deposited nanocomposite coating showed significant WCA and SA (168° and 3.1° respectively).
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