| 1. |
- Ali, Muhammad Amjad, et al.
(författare)
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Transcription factors WRKY11 and WRKY17 are involved in abiotic stress responses in Arabidopsis
- 2018
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Ingår i: Journal of plant physiology (Print). - : Elsevier. - 0176-1617 .- 1618-1328. ; 226, s. 12-21
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Tidskriftsartikel (refereegranskat)abstract
- Plant WRKY transcription factors play a vital role in abiotic stress tolerance and regulation of plant defense responses. This study examined AtWRKY11 and AtWRKY17 expression under ABA, salt, and osmotic stress at different developmental stages in Arabidopsis. We used reverse transcriptase PCR, quantitative real-time PCR, and promoter:GUS lines to analyze expression. Both genes were upregulated in response to abiotic stress. Next, we applied the same stressors to seedlings of T-DNA insertion wrky11 and 17 knock-out mutants (single and double). Under stress, the mutants exhibited slower germination and compromised root growth compared with the wild type. In most cases, double-mutant seedlings were more affected than single mutants. These results suggest that wrky11 and wrky17 are not strictly limited to plant defense responses but are also involved in conferring stress tolerance.
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| 2. |
- Amjad, Um-e-Salma, et al.
(författare)
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Catalytic cracking of polystyrene pyrolysis oil: Effect of Nb2O5 and NiO/Nb2O5 catalyst on the liquid product composition
- 2022
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Ingår i: Waste Management. - : Elsevier. - 0956-053X .- 1879-2456. ; 141, s. 240-250
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Tidskriftsartikel (refereegranskat)abstract
- The catalytic cracking of polystyrene pyrolysis oil was investigated over a Nb2O5 and a NiO/Nb2O5 catalyst in a fixed bed reactor. First, the pyrolysis of two different polystyrene feedstock (polystyrene foam and polystyrene pellet) was carried out in a semi-batch reactor, and the resulting polystyrene pellets pyrolysis oil was selected for catalytic cracking reaction because of its high liquid yield (85%). Catalytic cracking experiments were then performed at different temperatures (350–500 °C) using Nb2O5 or NiO/Nb2O5 catalyst. Gas chromatography–mass spectrometry analysis of liquid product obtained from the catalytic cracking process showed that the dimers in the pyrolysis oil were converted to monomers during the catalytic cracking process. The catalytic cracking results also showed that the NiO/Nb2O5 catalyst (having slightly higher acidic sites) had slightly higher activity for monomer conversion than the Nb2O5 catalyst (having less acidic sites). X-ray diffraction, transmission electron microscopy, pyridine Fourier transform infrared spectroscopy, NH3 Temperature Programmed Desorption and X-ray photoelectron spectroscopy were used to characterize the catalyst. The highest catalytic cracking activity was observed at 400 °C with the Nb2O5 catalyst with 4% toluene, 6% ethylbenzene, approximately 50% styrene, 13% α-methyl styrene, and only 6% of dimers in the liquid oil. The increase in temperature positively affected the yield of gases during catalytic cracking process.
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| 3. |
- Ali, Amjad, et al.
(författare)
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Effect of Manganese Catalysts on the Performance of Anodes in Direct Carbon Fuel Cells
- 2022
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Ingår i: ACS Applied Energy Materials. - : AMER CHEMICAL SOC. - 2574-0962. ; 5:6, s. 6878-6885
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Tidskriftsartikel (refereegranskat)abstract
- The efficiency of direct carbon fuel cells is higher than that of solid oxide fuel cells. The direct carbon fuel cell transforms chemical energy into electrical energy. In this work, the La0.4Sr0.6MnxTi1-xO3-delta (x = 0.02, 0.04, 0.06, 0.08) anode material has been synthesized by the combustion method to examine the device performance. X-ray analysis confirmed the single-perovskite cubic structure with an average crystalline size of 80 nm. An electrical conductivity of 2.1 S cm-1 and fuel cell performance of 100 mW cm-2 at 600 degrees C are measured with sub-bituminous fuel. Theoretical results describe the minor contribution of manganese (Mn) in the valence band and the major one in the conduction band, and with minimum energy, the Mn electrons may jump in the conduction band. Moreover, density functional theory confirmed that with an increase in the Mn concentration, Mn and Ti energy states appear at the Fermi level, which reveals that the conductivity of the compound has improved, agreeing with the experimental results that the Mn concentration led to the enhancement of the conductivity.
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| 4. |
- Ali, Amjad, et al.
(författare)
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Electrochemical Analysis of a Titanate-Based Anode for Direct Carbon Fuel Cells
- 2020
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Ingår i: ACS Applied Energy Materials. - : American Chemical Society (ACS). - 2574-0962. ; 3:9, s. 9182-9189
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Tidskriftsartikel (refereegranskat)abstract
- The grand challenge in the commercialization of direct carbon fuel cell (DCFC) technology is the development of a cost-effective and thermally stable material, which facilitates fast ionic and electronic conduction and exhibits good resistance for carbon deposition at electrodes. Titanate-based materials have high ionic and electronic conductivity at higher temperature. Perovskite anodes based on titanate and transition metals show a good catalytic activity for hydrocarbon fuels. Therefore, perovskite materials, based on lanthanum strontium and copper titanate La0.4Sr0.6CuxTi1-3O3-delta (x = 0.02, 0.04, 0.06, and 0.08), were synthesized using the sol-gel method and examined as anodes for DCFCs. The powders were analyzed using various characterization techniques. X-ray diffraction shows that the material has a cubic perovskite structure. The conductivity of the synthesized powder LS8CT was found to be 4.21 Scm(-1) at 600 degrees C. The button cell developed using LS8CT exhibits a performance of 61mWcm 72. at 600 degrees C. The computational study using the Wien2k code has been performed, which shows that the Fermi level is at nonzero density of states (DOS) and reveals that the compound is metallic in nature. Therefore, no forbidden region occurs between the maxima of the valence band and minima of the conduction band. Results of DOS confirm the metallic nature of the compound. On the basis of theoretical and experimental studies, it can be depicted that substitution of Cu in La0.3Sr0.7TiO3 increases the conductivity. Therefore, a La0.4Sr0.6CuxTi1-xO3-delta perovskite material can be used as an anode for DCFCs.
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| 5. |
- Amin, Muhammad, et al.
(författare)
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Life cycle assessment of iron-biomass supported catalyst for Fischer Tropsch synthesis
- 2024
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Ingår i: Frontiers in Chemistry. - : Frontiers Media S.A.. - 2296-2646. ; 12
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Tidskriftsartikel (refereegranskat)abstract
- The iron-based biomass-supported catalyst has been used for Fischer-Tropsch synthesis (FTS). However, there is no study regarding the life cycle assessment (LCA) of biomass-supported iron catalysts published in the literature. This study discusses a biomass-supported iron catalyst’s LCA for the conversion of syngas into a liquid fuel product. The waste biomass is one of the source of activated carbon (AC), and it has been used as a support for the catalyst. The FTS reactions are carried out in the fixed-bed reactor at low or high temperatures. The use of promoters in the preparation of catalysts usually enhances C5+ production. In this study, the collection of precise data from on-site laboratory conditions is of utmost importance to ensure the credibility and validity of the study’s outcomes. The environmental impact assessment modeling was carried out using the OpenLCA 1.10.3 software. The LCA results reveals that the synthesis process of iron-based biomass supported catalyst yields a total impact score in terms of global warming potential (GWP) of 1.235E + 01 kg CO2 equivalent. Within this process, the AC stage contributes 52% to the overall GWP, while the preparation stage for the catalyst precursor contributes 48%. The comprehensive evaluation of the iron-based biomass supported catalyst’s impact score in terms of human toxicity reveals a total score of 1.98E−02 kg 1,4-dichlorobenzene (1,4-DB) equivalent.
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| 6. |
- Amjad, Muhammad Raiees, et al.
(författare)
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Carbonate Reservoir Quality Variations in Basins with a Variable Sediment Influx: A Case Study from the Balkassar Oil Field, Potwar, Pakistan
- 2023
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Ingår i: ACS Omega. - : American Chemical Society (ACS). - 2470-1343. ; 8:4, s. 4127-4145
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Tidskriftsartikel (refereegranskat)abstract
- The carbonate reservoir quality is strongly reliant on the compaction process during sediment burial and other processes such as cementation and dissolution. Porosity and pore pressure are the two main factors directly affected by mechanical and chemical compactions. Porosity reduction in these carbonates is critically dependent on the overburden stress and subsidence rate. A variable sediment influx in younger basins may lead to changes in the reservoir quality in response to increasing lithostatic pressure. Deposition of molasse sediments as a result of the Himalayan orogeny caused variations in the sedimentation influx in the Potwar Basin of Pakistan throughout the Neogene times. The basic idea of this study is to analyze the carbonate reservoir quality variations induced by the compaction and variable sediment influx. The Sakesar Limestone of the Eocene age, one of the proven carbonate reservoirs in the Potwar Basin, shows significant changes in the reservoir quality, specifically in terms of porosity and pressure. A 3D seismic cube (10 km2) and three wells of the Balkassar field are used for this analysis. To determine the vertical and lateral changes of porosity in the Balkassar area, porosity is computed from both the log and seismic data. The results of both the data sets indicate 2–4% porosities in the Sakesar Limestone. The porosity reduction rate with respect to the lithostatic pressure computed with the help of geohistory analysis represents a sharp decrease in porosity values during the Miocene times. Pore pressure predictions in the Balkassar OXY 01 well indicate underpressure conditions in the Sakesar Limestone. The Eocene limestones deposited before the collision of the Indian plate had enough time for fluid expulsion and show underpressure conditions with high porosities.
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| 7. |
- Hussain, Arif, et al.
(författare)
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Methoxy-methylheptane as a cleaner fuel additive : An energy- and cost-efficient enhancement for separation and purification units
- 2021
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Ingår i: Energy Science & Engineering. - : John Wiley & Sons. - 2050-0505. ; :9, s. 1632-1646
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Tidskriftsartikel (refereegranskat)abstract
- Environmental protection agencies have begun imposing stringent regulations on the existing refineries to control the levels of gasoline additives. In this context, a novel compound, 2-methoxy-2-methylheptane (MMH), had drawn attention as fuel additive for cleaner combustion. The conventional process of MMH production features three distillation columns in a direct sequence. These columns are used to maintain the required product purities and to utilize the unreacted reactants through recycling streams. The distillation system of the existing MMH plant can afford significant energy savings, leading to a reduction in the total annual costs (TAC). The aim of this investigation is to demonstrate that the reported conventional process can be significantly enhanced by modifying the design and operational parameters and by replacing two distillation columns with an intensified dividing wall column (DWC) configuration. The DWC design is further optimized using several algorithms such as the modified coordinate method (MCD), robust particle swarm paradigm (PSP), and firefly (FF) with nonlinear constraints. Compared to conventional process, the optimized DWC resulted in 24% and 11.5% savings in the plant operating and total annual costs, respectively.
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| 8. |
- Imran, Qari Muhammad, et al.
(författare)
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Transcriptome wide identification and characterization of NO-responsive WRKY transcription factors in Arabidopsis thaliana L.
- 2018
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Ingår i: Environmental and Experimental Botany. - : Elsevier. - 0098-8472 .- 1873-7307. ; 148, s. 128-143
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Tidskriftsartikel (refereegranskat)abstract
- WRKY transcription factors are important plant-specific regulatory genes characterized by one or two conserved WRKY domain(s) usually followed by a zinc-finger motif. In this study using Arabidopsis thaliana, the RNA-Seq based transcriptomic analysis showed differential expression of 33 genes encoding WRKY TFs in response to the nitric oxide (NO) donor S-Nitrosocysteine (CySNO). Interestingly, 93.9% of these TFs were up-regulated with at least 2-fold change, suggesting their putative involvement in NO mediated gene regulation. GO- analysis of all the 33 transcriptomic elements showed their putative involvement in biological processes such as abiotic stress tolerance and defense against fungal pathogens (89.39 fold enrichment). Analysis of the NO-responsive AtWRKY TFs promoter region revealed the presence of the cis-acting elements such as ABRE, EIRE, ERE, and MBS involved in osmotic stress response, maximal elicitor-mediated activation, and drought-stress regulation. The analysis of NO-responsive AtWRKY TF motifs and their comparison with rice, soybean, and tomato orthologs suggested that members of the WRKY family belonging to the same group shared similar motifs and phylogenetic tree suggested that these TFs were highly conserved. Validation of transcriptomic data through quantitative real time-PCR showed a high correlation coefficient (0.85) indicating the high reliability and similarity of both types of analysis. Comparison of the NO-responsive and non-responsive WRKYs showed the presence of tyrosine (T) and cysteine (C) residues at a distance of 7 residues from the WRKYGQK motif which may serve as potential targets for modification by NO via tyrosine nitration and S-nitrosylation. We also validated the response of WRKYs through in vivo analysis using atwrky62 loss of function mutant and the results indicated a negative role of AtWRKY62 in plant growth. Furthermore, atwrky62 showed significantly less SNO contents compared to wild type plants indicating putative role of AtWRKY62 in NO metabolism.
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| 9. |
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| 10. |
- Munir, M. Adeel, et al.
(författare)
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Blockchain Adoption for Sustainable Supply Chain Management : Economic, Environmental, and Social Perspectives
- 2022
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Ingår i: Frontiers in Energy Research. - : Frontiers Media S.A.. - 2296-598X. ; 10
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Tidskriftsartikel (refereegranskat)abstract
- Due to the rapid increase in environmental degradation and depletion of natural resources, the focus of researchers is shifted from economic to socio-environmental problems. Blockchain is a disruptive technology that has the potential to restructure the entire supply chain for sustainable practices. Blockchain is a distributed ledger that provides a digital database for recording all the transactions of the supply chain. The main purpose of this research is to explore the literature relevant to blockchain for sustainable supply chain management. The focus of this review is on the sustainability of the blockchain-based supply chain concerning environmental conservation, social equality, and governance effectiveness. Using a systematic literature review, a total of 136 articles were evaluated and categorized according to the triple bottom-line aspects of sustainability. Challenges and barriers during blockchain adoption in different industrial sectors such as aviation, shipping, agriculture and food, manufacturing, automotive, pharmaceutical, and textile industries were critically examined. This study has not only explored the economic, environmental, and social impacts of blockchain but also highlighted the emerging trends in a circular supply chain with current developments of advanced technologies along with their critical success factors. Furthermore, research areas and gaps in the existing research are discussed, and future research directions are suggested. The findings of this study show that blockchain has the potential to revolutionize the entire supply chain from a sustainability perspective. Blockchain will not only improve the economic sustainability of the supply chain through effective traceability, enhanced visibility through information sharing, transparency in processes, and decentralization of the entire structure but also will help in achieving environmental and social sustainability through resource efficiency, accountability, smart contracts, trust development, and fraud prevention. The study will be helpful for managers and practitioners to understand the procedure of blockchain adoption and to increase the probability of its successful implementation to develop a sustainable supply chain network.
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