| 1. |
- Thomas, HS, et al.
(författare)
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- 2019
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swepub:Mat__t
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| 2. |
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| 3. |
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| 4. |
- Ahmed, A., et al.
(författare)
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Highly efficient composite electrolyte for natural gas fed fuel cell
- 2016
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Ingår i: International journal of hydrogen energy. - : Elsevier. - 0360-3199 .- 1879-3487. ; 41:16, s. 6972-6979
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Tidskriftsartikel (refereegranskat)abstract
- Solid oxide fuel cells (SOFCs) have the ability to operate with different variants of hydro carbon fuel such as biogas, natural gas, methane, ethane, syngas, methanol, ethanol, hydrogen and any other hydrogen rich gas. Utilization of these fuels in SOFC, especially the natural gas, would significantly reduce operating cost and would enhance the viability for commercialization of FC technology. In this paper, the performance of two indigenously manufactured nanocomposite electrolytes; barium and samarium doped ceria (BSDC-carbonate); and lanthanum and samarium doped ceria (co-precipitation method LSDC-carbonate) using natural gas as fuel is discussed. The nanocomposite electrolytes were synthesized using co-precipitation and wet chemical methods (here after referred to as nano electrolytes). The structure and morphology of the nano electrolytes were examined by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The fuel cell performance (OCV) was tested at temperature (300-600 °C). The ionic conductivity of the nano electrolytes were measured by two probe DC method. The detailed composition analysis of nano electrolytes was performed with the help of Raman Spectroscopy. Electrochemical study has shown an ionic conductivity of 0.16 Scm-1 at 600 °C for BSDC-carbonate in hydrogen atmosphere, which is higher than conventional electrolytes SDC and GDC under same conditions. In this article reasonably good ionic conductivity of BSDC-carbonate, at 600 °C, has also been achieved in air atmosphere which is comparatively greater than the conventional SDC and GDC electrolytes.
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| 5. |
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| 6. |
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| 7. |
- Javed, A., et al.
(författare)
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Study of Effect of Superstrate on Wideband Array Antenna
- 2019
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Ingår i: RAEE 2019 - International Symposium on Recent Advances in Electrical Engineering. - : Institute of Electrical and Electronics Engineers Inc.. - 9781728130729
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Konferensbidrag (refereegranskat)abstract
- This article presents a twelve-element based wideband microstrip linear array antenna. In the array design, the elements are studded with stubs to enhance the bandwidth. Resonances are achieved in the broader band by introducing the slotted ground. The design is equipped with superstrate at a specific distance from the array antenna to improve the gain and efficiency. The proposed work has a good percentage bandwidth of 43.28% with stable radiation characteristics. The introduction of superstrate causes the proposed structure to enhance its peak gain to 7.6 dBi and the efficiency to 77%. The presented array covers the high-frequency spectrum from 24.343 GHz to 37.79 GHz, thus making it a good choice for millimeter wave applications.
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| 8. |
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| 9. |
- Kantarelis, Efthymios, PhD, 1982-, et al.
(författare)
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Engineering the Catalytic Properties of HZSM5 by Cobalt Modification and Post-synthetic Hierarchical Porosity Development
- 2019
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Ingår i: Topics in catalysis. - : Springer Science and Business Media LLC. - 1022-5528 .- 1572-9028. ; 62:7, s. 773-785
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Tidskriftsartikel (refereegranskat)abstract
- Hierarchical zeolites have been identified as special catalytic materials with improved catalytic properties. In this study, hierarchical bifunctional ZSM5 based catalysts were prepared by desilication for controlled mesoporosity development and have been modified by Co doping. Their performance in the catalytic pyrolysis of oak in a lab scale reactor was evaluated. Desilicated counterparts were proven more active in deoxygenation of bio oil, while carbon deposition on the catalysts reduced compared to non-desilicated counterparts. Increased Lewis acidity favors decarboxylation reactions, while higher olefins as well as PAH content indicate easier diffusion within and from the porous network and interactions in the mesopores. The conversion of bulky lignin molecules (alkoxy phenols) is enhanced by the mesopores, while acidity is of secondary importance. Coke deposition inside the pores is more profound in the desilicated catalysts due to larger pore size. Carbon deposition on the catalysts is reduced in the following order: HZSM5 > Co/HZSM5 > Ds-HZSM5 > Co/Ds-HZSM5. GC–MS characterization of the CH2Cl2 soluble coke indicated that for the desilicated counterparts the main coke precursors are the bulky lignin molecules which are partially deoxygenated.
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| 10. |
- Raza, Rizwan, et al.
(författare)
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Composite electrolyte with proton conductivity for low-temperature solid oxide fuel cell
- 2015
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Ingår i: Applied Physics Letters. - : American Institute of Physics (AIP). - 0003-6951 .- 1077-3118. ; 107:18
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Tidskriftsartikel (refereegranskat)abstract
- In the present work, cost-effective nanocomposite electrolyte (Ba-SDC) oxide is developed for efficient low-temperature solid oxide fuel cells (LTSOFCs). Analysis has shown that dual phase conduction of O-2 (oxygen ions) and H+ (protons) plays a significant role in the development of advanced LTSOFCs. Comparatively high proton ion conductivity (0.19 s/cm) for LTSOFCs was achieved at low temperature (460°C). In this article, the ionic conduction behaviour of LTSOFCs is explained by carrying out electrochemical impedance spectroscopy measurements. Further, the phase and structure analysis are investigated by X-ray diffraction and scanning electron microscopy techniques. Finally, we achieved an ionic transport number of the composite electrolyte for LTSOFCs as high as 0.95 and energy and power density of 90% and 550 mW/cm2, respectively, after sintering the composite electrolyte at 800°C for 4 h, which is promising. Our current effort toward the development of an efficient, green, low-temperature solid oxide fuel cell with the incorporation of high proton conductivity composite electrolyte may open frontiers in the fields of energy and fuel cell technology.
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| 11. |
- Raza, Rizwan, et al.
(författare)
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Fuel cell technology for sustainable development in Pakistan - An over-view
- 2016
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Ingår i: Renewable & sustainable energy reviews. - : Elsevier. - 1364-0321 .- 1879-0690. ; 53, s. 450-461
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Tidskriftsartikel (refereegranskat)abstract
- Fuel cell technology holds the combination of benefits, which are barely offered by any other energy generating technology. Because the fuel used in this technology is found in abundance in nature and can also be renewed/sustained. Pakistan is blessed with renewable energy resources which are suitable for fuel cell technology. Therefore, fuel cell technology offers a great opportunity to meet the demand of energy and for the sustainable development of Pakistan. The energy research group at COMSATS Institute of Information Technology (CIIT), Lahore has made efforts to study the technical aspects of fuel cell technology and its commercial benefits. The research group is interested in finding ways and means of generating and storing the energy produced by using fuel cells. In this paper, the research activities on fuel cell technology in Pakistan have been reviewed and it is also discussed how this technology can resolve the current energy crises in Pakistan and can be the source of sustainable energy. It has been also reviewed that the country would greatly benefit from fuel cells and fuel cell hybrid system (environmental friendly technology), which could be the best solution for electricity production as well for automobile industry.
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| 12. |
- Smith, Gustav, et al.
(författare)
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Discovery of Genetic Variation on Chromosome 5q22 Associated with Mortality in Heart Failure
- 2016
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Ingår i: PLoS Genetics. - : Public Library of Science (PLoS). - 1553-7390 .- 1553-7404. ; 12:5
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Tidskriftsartikel (refereegranskat)abstract
- Failure of the human heart to maintain sufficient output of blood for the demands of the body, heart failure, is a common condition with high mortality even with modern therapeutic alternatives. To identify molecular determinants of mortality in patients with new-onset heart failure, we performed a meta-analysis of genome-wide association studies and follow-up genotyping in independent populations. We identified and replicated an association for a genetic variant on chromosome 5q22 with 36% increased risk of death in subjects with heart failure (rs9885413, P = 2.7x10-9). We provide evidence from reporter gene assays, computational predictions and epigenomic marks that this polymorphism increases activity of an enhancer region active in multiple human tissues. The polymorphism was further reproducibly associated with a DNA methylation signature in whole blood (P = 4.5x10-40) that also associated with allergic sensitization and expression in blood of the cytokine TSLP (P = 1.1x10-4). Knockdown of the transcription factor predicted to bind the enhancer region (NHLH1) in a human cell line (HEK293) expressing NHLH1 resulted in lower TSLP expression. In addition, we observed evidence of recent positive selection acting on the risk allele in populations of African descent. Our findings provide novel genetic leads to factors that influence mortality in patients with heart failure.
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| 13. |
- Beier, Richard A., et al.
(författare)
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Validation of borehole heat exchanger models against multi-flow rate thermal response tests
- 2018
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Ingår i: Geothermics. - : Elsevier BV. - 0375-6505. ; 71, s. 55-68
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Tidskriftsartikel (refereegranskat)abstract
- A recently developed vertical borehole ground heat exchanger model that accounts for transit time effects and time-varying short-circuiting heat transfer has been validated against two multi-flow-rate thermal response tests (MFR-TRT). The MFR-TRT, when performed with a wide range of flow rates, results in significant changes in the borehole thermal resistance, the borehole internal thermal resistance, and the short-circuiting heat transfer between the two legs of a single U-tube. The model accounts for short-circuiting by an analytically computed weighting factor that is used to determine the mean fluid temperature. The weighting factor portion of the model can be readily utilized in other ground heat exchanger models that currently rely on a simple mean fluid temperature. Use of the weighting factor is shown to give significantly better estimations of entering and exiting fluid temperature than using the simple mean fluid temperature. The new model is also compared to an alternative approach using an effective borehole thermal resistance. While both the effective borehole thermal resistance model and the weighting factor give quite good results a few hours after a step change in flow rate, the weighting factor model gives much better results in the first few hours after a step change in flow rate.
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| 14. |
- Bournas, Iason, et al.
(författare)
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Energy renovation of an office building using a holistic design approach
- 2016
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Ingår i: Journal of Building Engineering. - : Elsevier BV. - 2352-7102. ; 7:September 2016, s. 194-206
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Tidskriftsartikel (refereegranskat)abstract
- This paper presents a holistic approach to perform energy renovations of office buildings. A real case study is used to demonstrate how different software can be used to facilitate the work of architects and engineers during different design stages. Initially, the moisture safety of the building is coupled to its energy performance to define the optimum insulation level. The new interior layout is based on an initial daylight study, rather than on architectural intuition. On a second stage, shading and natural ventilation are studied to eradicate any cooling demand, while the interdependence between heating energy and daylight is assessed for the use of light-wells. To demonstrate the trade-offs between visual control and electrical lighting, different shading systems are examined for a cellular office. Finally, two alternate HVAC systems are analyzed to investigate whether passive standards can be achieved with an all-air system and/or a hydronic system.
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| 15. |
- Guezgouz, M., et al.
(författare)
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Optimal hybrid pumped hydro-battery storage scheme for off-grid renewable energy systems
- 2019
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Ingår i: Energy Conversion and Management. - : Elsevier Ltd. - 0196-8904 .- 1879-2227. ; 199
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Tidskriftsartikel (refereegranskat)abstract
- The development of energy storage systems paves the way towards a high integration of renewable energy sources in the electricity generation sector. Considering above, this paper introduces a new energy management strategy to efficiently coordinate a hybrid energy storage system based on pumped hydro storage (long term bulk storage) with batteries (short term, more flexible). For the purpose of this analysis, hourly time series of irradiation, wind speed, temperature and real measured load (characteristic for farmstead) covering one year were gathered for the selected site in Algeria. The optimal size of the system is determined based on a multi-objective optimization using a grey wolf optimizer implemented in MATLAB software. The results indicate that the hybrid storage system enables achieving higher reliability at lower cost in comparison to a system with single storage technology. The use of hybrid storage also reduces the curtailment of renewable generation. Further findings reveal that the cost of an optimal energy supply system with 97.5% reliability is 0.162 €/kWh, 0.207 €/kWh and 1.462 €/kWh for hybrid storage, battery and pumped storage, respectively. However, sensitivity analysis shows that the optimal hybrid storage configuration is less resilient when changes in irradiation/temperature/load are considered. This indicates that special actions (upscale of installed power) must be undertaken to avoid lower performance of hybrid storage systems. In summary, the hybrid storage system seems to be better sized for consideration in optimized solar/wind conditions, but by avoiding oversizing they are less resilient to future potential changes in renewable energy availability.
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| 16. |
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| 17. |
- Javed, Muhammad Ahsan, et al.
(författare)
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Impact of intensified chemotherapy in metastatic pancreatic ductal adenocarcinoma (PDAC) in clinical routine in Europe
- 2019
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Ingår i: Pancreatology (Print). - : Elsevier. - 1424-3903 .- 1424-3911. ; 19:1, s. 97-104
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is associated with poor prognosis. Gemcitabine is the standard chemotherapy for patients with metastatic pancreatic adenocarcinoma (MPA). Randomized clinical trials evaluating intensified chemotherapies including FOLFIRINOX and nab-paclitaxel plus gemcitabine (NAB+GEM) have shown improvement in survival. Here, we have evaluated the efficacy of intensified chemotherapy versus gemcitabine monotherapy in real-life settings across Europe.METHODS: A retrospective multi-center study including 1056 MPA patients, between 2012 and 2015, from nine centers in UK, Germany, Italy, Hungary and the Swedish registry was performed. Follow-up was at least 12 months. Cox proportional Harzards regression was used for uni- and multivariable evaluation of prognostic factors.RESULTS: Of 1056 MPA patients, 1030 (98.7%) were assessable for survival analysis. Gemcitabine monotherapy was the most commonly used regimen (41.3%), compared to FOLFIRINOX (n = 204, 19.3%), NAB+GEM (n = 81, 7.7%) and other gemcitabine- or 5-FU-based regimens (n = 335, 31.7%). The median overall survival (OS) was: FOLFIRINOX 9.9 months (95%CI 8.4-12.6), NAB+GEM 7.9 months (95%CI 6.2-10.0), other combinations 8.5 months (95%CI 7.7-9.3) and gemcitabine monotherapy 4.9 months (95%CI 4.4-5.6). Compared to gemcitabine monotherapy, any combination of chemotherapeutics improved the survival with no significant difference between the intensified regimens. Multivariable analysis showed an association between treatment center, male gender, inoperability at diagnosis and performance status (ECOG 1-3) with poor prognosis.CONCLUSION: Gemcitabine monotherapy was predominantly used in 2012-2015. Intensified chemotherapy improved OS in comparison to gemcitabine monotherapy. In real-life settings, the OS rates of different treatment approaches are lower than shown in randomized phase III trials.
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| 18. |
- Javed, Muhammad Atif, et al.
(författare)
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Towards variant management and change impact analysis in safety-oriented process-product lines
- 2019
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Ingår i: Proceedings of the ACM Symposium on Applied Computing. - New York, NY, USA : Association for Computing Machinery. ; , s. 2372-2375
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Konferensbidrag (refereegranskat)abstract
- In safety-critical (software) systems, safety management embraces both processes and products, which due to e.g., product's upgrade, tend to be tailored, giving rise to safety-oriented product lines and corresponding safety-oriented process lines. To tailor these lines systematically, their inter-dependencies would have been taken into consideration. To date, however, no satisfying implemented solution is available on the shelf. Accordingly, this paper focuses on the co-engineering of process and product lines. At first, the process and product lines need to be established for which the integration between Eclipse Process Framework (EPF) Composer, Composition with Guarantees for High-integrity Embedded Software Components Assembly (CHESS) Tool and Base Variability Resolution (BVR) Tool is achieved; they are process engineering, product design and variant management solutions, respectively. After that, the process and product lines are integrated. This is done for cross-dimension variant management and change impact analysis. The applicability of the integrated lines is illustrated for the attitude and orbit control subsystem.
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| 19. |
- Le, Nha, et al.
(författare)
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Real-world clinical practice of intensified chemotherapies for metastatic pancreatic cancer : results from a Pan-European questionnaire study
- 2016
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Ingår i: Digestion. - : S. Karger AG. - 0012-2823 .- 1421-9867. ; 94:4, s. 222-229
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: Recently, FOLFIRINOX and gemcitabine + nab-paclitaxel have been introduced as a novel intensified chemotherapy regimen for patients with metastasized pancreatic cancer. This study aims to analyze the real-world clinical practice with FOLFIRINOX and gemcitabine + nab-paclitaxel across Europe.Methods: Invitations to participate in an anonymous web-based questionnaire were sent via e-mail to 5,420 doctors in 19 European countries through the network of national gastroenterological, oncological, surgical and pancreatic societies as well as the European Pancreatic Club. The questionnaire consisted of 20 questions, 14 regarding the use of intensified chemotherapy, 4 regarding demographics of the participants, and 1 to verify the active involvement in the management of metastatic pancreatic cancer.Results: Two hundred and thirteen responses were received and 153 entries were valid for analysis. Of those, 63.4% came from an academic institution, 51% were oncologists, and 52% treated more than 25 cases per year. A majority of responses (71%) were from Italy (40%), Germany (23%), and Spain (8%). As first-line therapy, 11% used gemcitabine +/- erlotinib, 42% used FOLFIRINOX, and 47% used gemcitabine + nab-paclitaxel. Of the intensified regimens, both were applied to equal parts, but the likelihood of protocol deviation was higher when using FOLFIRINOX (p < 0.01). FOLFIRINOX was considered more toxic than gemcitabine + nab-paclitaxel (neutropenia 88 vs. 68%; polyneuropathy 42 vs. 41%; rapid deterioration 42 vs. 31%). FOLFIRINOX was rated to achieve longer survival with an acceptable quality of life (52 vs. 44%). Moreover, 57% of participants thought that gemcitabine + nab-paclitaxel should be the backbone for further clinical trials in pancreatic cancer.Conclusion: Intensified chemotherapy is widely used in pancreatic cancer patients in Europe following its recent clinical approval. Interestingly, nab-paclitaxel and FOLFIRINOX were used at comparable frequency although the latter had to be de-escalated more often.
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| 20. |
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| 21. |
- Schober, Marvin, et al.
(författare)
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New Advances in the Treatment of Metastatic Pancreatic Cancer
- 2015
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Ingår i: Digestion. - : S. Karger. - 0012-2823 .- 1421-9867. ; 92:3, s. 175-184
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Forskningsöversikt (refereegranskat)abstract
- Background: Pancreatic ductal adenocarcinoma (PDAC) is characterised by an extremely poor overall survival (OS) compared to other solid tumours. As the incidence of the disease is rising and the treatment options are limited, PDAC is projected to be the 2nd leading cause of cancer-related deaths in the United States by 2030. A majority of patients are not eligible for curative resection at the time of diagnosis, and those that are resected will often relapse within the first few years after surgery. Summary: Until recently, the nucleoside analogue gemcitabine has been the standard of care for patients with non-resectable PDAC with only marginal effects on OS. In 2011, the gemcitabine-free FOLFIRINOX regimen (folinic acid, fluorouracil, irinotecan and oxaliplatin) showed a significant survival advantage for patients with metastatic PDAC in a phase III trial. In 2013, the Metastatic Pancreatic Adenocarcinoma Trial phase III trial with nano-formulated albumin-bound paclitaxel (nab-paclitaxel) in combination with gemcitabine also resulted in a significant survival extension compared to gemcitabine monotherapy. However, both intensified therapy regimens show a broad spectrum of side effects and patients need to be carefully selected for the most appropriate protocol. Key Message: In this study, recent advances in the chemotherapeutic options available to treat metastatic PDAC and their implications for today's treatment choices are reviewed.
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| 22. |
- Shahid, M., et al.
(författare)
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Serratia sp. CP-13 augments the growth of cadmium (Cd)-stressed Linum usitatissimum L. by limited Cd uptake, enhanced nutrient acquisition and antioxidative potential
- 2019
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Ingår i: Journal of Applied Microbiology. - : Oxford University Press (OUP). - 1364-5072 .- 1365-2672. ; 126:6, s. 1708-1721
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Tidskriftsartikel (refereegranskat)abstract
- Aims: The current study was aimed to evaluate the beneficial effects and bioremediation potential of a Cd-tolerant bacterial strain, Serratia sp. CP-13, on the physiological and biochemical functions of Linum usitatissimum L., under Cd stress.Methods and Results: The bacterial strain was isolated from the wastewater collection point of Chakera, Faisalabad, Pakistan, as this place contains industrial wastewater of the Faisalabad region. The Serratia sp. CP-13, identified through 16S rRNA gene sequence analysis, exhibited a significant phyto-beneficial potential in terms of in vitro inorganic phosphate solubilization, indole-3-acetic acid production and 1-aminocyclopropane-1-carboxylic acid deaminase activity. Effects of Serratia sp. CP-13 inoculation on L. usitatissimum were evaluated by growing the plants in CdCl2 (0, 5 or 10 mg kg(-1) dry soil)-spiked soil. Without inoculation of Serratia sp. CP-13, Cd stress significantly reduced the plant biomass as well as the quantity of proteins and photosynthetic pigments due to enhanced H2O2, malondialdehyde (MDA) contents and impaired nutrient homeostasis. Subsequently, Serratia sp. CP-13 increased the plant fresh and dry biomass, plant antioxidation capacity, whereas it decreased the lipid peroxidation under Cd stress. In parallel, Serratia sp. inoculation assisted the Cd-stressed plants to maintain an optimum level of nutrients (K, Ca, P, Mg, Fe and Mn).Conclusions: The isolated bacterial strain (Serratia sp. CP-13) when applied to Cd-stressed L. usitatissimum inhibited the Cd uptake, reduced Cd-induced lipid peroxidation, maintained the optimum level of nutrients and thereby, enhanced L. usitatissimum growth. The analysis of bio-concentration and translocation factor revealed that L. usitatissimum with Serratia sp. CP-13 inoculation sequestered Cd in plant rhizospheric zone.Significance and Impact of the Study: Serratia sp. CP-13 inoculation is a potential candidate for the development of low Cd-accumulating linseed and could be used for phytostabilization of Cd-contaminated rhizosphere/soil colloids.
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| 23. |
- Shoravi, Siamak, et al.
(författare)
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In silico screening of molecular imprinting prepolymerization systems : oseltamivir selective polymers through full-system molecular dynamics-based studies
- 2016
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Ingår i: Organic and biomolecular chemistry. - : Royal Society of Chemistry (RSC). - 1477-0520 .- 1477-0539. ; 14:18, s. 4210-4219
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Tidskriftsartikel (refereegranskat)abstract
- All-component molecular dynamics studies were used to probe a library of oseltamivir molecularly imprinted polymer prepolymerization mixtures. Polymers included one of five functional monomers (acrylamide, hydroxyethylmethacrylate, methacrylic acid, 2-(triflouromethyl)acrylic acid, 4-vinylpyridine) and one of three porogens (acetonitrile, chloroform, methanol) combined with the crosslinking agent ethylene glycol dimethacrylate and initiator 2,2'-azobis(2-methylpropionitrile). Polymers were characterized by nitrogen gas sorption measurements and SEM, and affinity studies performed using radioligand binding in various media. In agreement with the predictions made from the simulations, polymers prepared in acetonitrile using either methacrylic or trifluoromethacrylic acid demonstrated the highest affinities for oseltamivir. Further, the ensemble of interactions observed in the methanol system provided an explanation for the morphology of polymers prepared in this solvent. The materials developed here offer potential for use in solid-phase extraction or for catalysis. The results illustrate the strength of this in silico strategy as a potential prognostic tool in molecularly imprinted polymer design.
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| 24. |
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| 25. |
- Woodman, Nick, et al.
(författare)
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Evaluating the applicability of the radial approximation for pile heat exchangers
- 2019. - 217729
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Ingår i: Energy Geotechnics. - Cham : Springer International Publishing. - 1866-8755. ; , s. 3-10
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Konferensbidrag (refereegranskat)abstract
- This paper appraises the efficacy of using an analytical radial approximation for different thermal pile heat exchanger geometries. Unsteady radial heat-flow from fluid in a pipe set within a grouted borehole into the external ground is well-documented and can be solved analytically very rapidly using Laplace Transforms (Javed and Claesson 2011). By comparing the radial model with finite-element simulations including explicit pile geometries, this paper provides a provisional analysis of the accuracy of this approach. Initial findings suggest that the radial model may provide an appropriate approximation to pile behaviour for certain pipe configurations, albeit with small ‘mid-time’ error.
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