| 1. |
- Ali, Asma Mahdi, et al.
(författare)
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Nonlinear Simulation Analysis of Mechanical Behaviour of Rubberized Concrete
- 2022
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Ingår i: International Journal of GEOMATE. - : GEOMATE International Society. - 2186-2982 .- 2186-2990. ; 22:90, s. 125-137
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Tidskriftsartikel (refereegranskat)abstract
- The main objective is to simulate the representation of rubber concrete with different percentages (0, 20, 40, 60, 80, 100%) of rubber using a finite element approach with ANSYS V.15 software to evaluate the behavior of concrete under the influence of mechanical force by using a standard cylinder to calculate its compressive strength, elasticity modulus and displacements for comparison with the previous experimental study, which showed a very close agreement of 5 to 12% when compared between them. The results showed that when the percentage of rubber increases, it leads to a decrease in the compressive strength, that is, its resistance, and an increase in the corresponding displacements and deformations that occur in them, as a result of the concentration of these stresses in the rubber limits. The results also showed that the meshing distribution of the analyzed elements by the ANSYS gave higher values of compressive strength and a decrease in the corresponding displacements when they were regular i.e. homogeneous compared to the irregular ones. Finally, through statistical analysis, it was found that the mean and arithmetic mean were acceptable and close when comparing the theoretical and practical results.
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| 2. |
- Chrysafi, Anna, et al.
(författare)
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Quantifying Earth system interactions for sustainable food production via expert elicitation
- 2022
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Ingår i: Nature Sustainability. - : Springer Science and Business Media LLC. - 2398-9629. ; 5:10, s. 830-842
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Tidskriftsartikel (refereegranskat)abstract
- Several safe boundaries of critical Earth system processes have already been crossed due to human perturbations; not accounting for their interactions may further narrow the safe operating space for humanity. Using expert knowledge elicitation, we explored interactions among seven variables representing Earth system processes relevant to food production, identifying many interactions little explored in Earth system literature. We found that green water and land system change affect other Earth system processes strongly, while land, freshwater and ocean components of biosphere integrity are the most impacted by other Earth system processes, most notably blue water and biogeochemical flows. We also mapped a complex network of mechanisms mediating these interactions and created a future research prioritization scheme based on interaction strengths and existing knowledge gaps. Our study improves the understanding of Earth system interactions, with sustainability implications including improved Earth system modelling and more explicit biophysical limits for future food production.
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| 3. |
- Shafie, Siti Nur Alwani, et al.
(författare)
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[EMIM][Tf2N]-Modified Silica as Filler in Mixed Matrix Membrane for Carbon Dioxide Separation
- 2021
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Ingår i: Membranes. - : MDPI. - 2077-0375. ; 11:5, s. 1-14
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Tidskriftsartikel (refereegranskat)abstract
- This study focuses on the effect of modified silica fillers by [EMIN][Tf2N] via physical adsorption on the CO2 separation performance of a mixed matrix membrane (MMM). The IL-modified silica was successfully synthesized as the presence of fluorine element was observed in both Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectrometer (XPS) analyses. The prepared MMMs with different loadings of the IL-modified silica were then compared with an unmodified silica counterpart and neat membrane. The morphology of IL-modified MMMs was observed to have insignificant changes, while polymer chains of were found to be slightly more flexible compared to their counterpart. At 2 bar of operating pressure, a significant increase in performance was observed with the incorporation of 3 wt% Sil-IL fillers compared to that of pure polycarbonate (PC). The permeability increased from 353 to 1151 Barrer while the CO2/CH4 selectivity increased from 20 to 76. The aforementioned increment also exceeded the Robeson upper bound. This indicates that the incorporation of fillers surface-modified with ionic liquid in an organic membrane is worth exploring for CO2 separation.
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