| 1. |
- Fu, Q. X., et al.
(författare)
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Doped ceria-chloride composite electrolyte for intermediate temperature ceramic membrane fuel cells
- 2002
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Ingår i: Materials letters (General ed.). - 0167-577X .- 1873-4979. ; 53:3, s. 186-192
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Tidskriftsartikel (refereegranskat)abstract
- A kind of oxide-salt composite electrolyte, gadolinium-doped ceria (GDC)-LiCl-SrCl2, prepared with hot-press technique, shows superior ionic conductivity, which is 2-10 times higher than that of GDC itself at the temperature range of 400-600 degreesC. More interestingly, not like the GDC electrolyte, which has some extent of electronic conduction under reducing atmosphere, the composite electrolyte is almost a pure ionic conductor, evidenced by the fuel cell's (FC) open circuit voltage (OCV) close to the theoretical one. The fuel cells based on this composite electrolyte show excellent power density output even at temperature as low as 500 degreesC (240 mW cm(-2)) in spite of the relatively thick electrolyte (0.4 mm). Such high performance, in combination with its low cost in both raw materials and fabrication process, make this kind of composite electrolyte a good candidate electrolyte material for future ultra-low-cost intermediate temperature ceramic membrane fuel cells (IT-CMFCs).
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| 2. |
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| 3. |
- Mathew, Aji P., et al.
(författare)
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Izod impact behavior of natural rubber/polystyrene interpenetrating polymer networks
- 2001
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Ingår i: Materials letters (General ed.). - 0167-577X .- 1873-4979. ; 50:2-3, s. 154-163
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Tidskriftsartikel (refereegranskat)abstract
- The impact behavior of semi and full interpenetrating polymer networks based on natural rubber (NR) and polystyrene (PS) has been studied with special reference to blend ratio and cross-linking level of PS phase. As the PS cross-linker level increases up to 4% an increase in impact strength values was observed. This behavior was explained based on blend morphology and the fractography. It was also found that in moderately cross-linked IPNs, the blend composition with 70% PS showed maximum impact strength values. At higher cross-linking levels, samples with 60% PS showed maximum impact strength values. The fracture surface morphology satisfactorily explained the nature of failure and impact performance in all cases. Addition of NR to PS has changed the failure mechanism from crazing to shear yielding
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| 4. |
- Strömme, Maria, et al.
(författare)
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What do we do with all these algae?
- 2002
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Ingår i: Materials letters (General ed.). - 0167-577X .- 1873-4979. ; 57:3, s. 569-572
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Tidskriftsartikel (refereegranskat)abstract
- The severe eutrophication of coastal areas is considered to be one of the most serious environmental threats of our time S. Nixon, Ambio 19 (1990) 101. Even if the nutrient outlet is curtailed, carpets of green algae filaments will remain for a long time as the algae life cycle feeds itself S. Naeem, D.R. Hahn, G. Schuurman, Nature 403 (2002) 762. One way to master this ecological problem is to remove algae from the cycle O. Jousson, J. Pawlowski, L. Zaninetti, F.W. Zechman, F. Dini, G. Di Guiseppe, R. Woodfield, A. Millar, A. Meinensz, Nature 408 (2000) 157. Hence, the necessity of finding some relevant use for green algae is obvious. It has been shown that cellulose powder from green algae sources has a higher level of crystallinity and a relatively larger surface area than higher plant cellulose R. Ek, C. Gustafsson, A. Nutt, T. Iversen, C, Nyström, J. Mol. Recognit. 11 (1998) 263. Could these properties possibly be advantageous in pharmaceutical tablet manufacturing? Here, we show that green algae filaments provide an alternative raw material source for the production of microcrystalline cellulose with a hitherto unobserved combination of properties desirable for a tableting excipient.
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| 5. |
- Toprak, Muhammet S., et al.
(författare)
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Chemical alloying and characterization of nanocrystalline bismuth telluride
- 2003
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Ingår i: Materials letters (General ed.). - : Elsevier BV. - 0167-577X .- 1873-4979. ; 57:24-25, s. 3976-3982
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Tidskriftsartikel (refereegranskat)abstract
- A novel chemical alloying method has been developed for the fabrication of nanocrystalline thermoelectric alloy Bismuth telluride, Bi2Te3. The method consists of a combination of solution chemical method and thermal processing under controlled heating conditions. The components have been coprecipitated from a solution and the precursor consists of a solid solution of the different intermediate compounds and exhibits high reactivity. Calcination and hydrogen reduction of the precursor at moderate temperature, 350 degreesC, for 2 h resulted in the alloying of these elements to obtain the pure phase of the thermoelectric material in fine powder. The method is simpler than conventional melt processing and produced a 95-98% yield in laboratory scale. High concentration of grain boundaries provided by nanostructuring is expected to lower the thermal conductivity of thermoelectric material and further increase the performance.
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| 6. |
- Korsunsky, Alexander M., et al.
(författare)
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Quantifying eigenstrain distributions induced by focused ion beam damage in silicon
- 2016
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Ingår i: Materials letters (General ed.). - : Elsevier. - 0167-577X .- 1873-4979. ; , s. 47-49
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Tidskriftsartikel (refereegranskat)abstract
- Abstract Eigenstrain offers a versatile generic framework for the description of inelastic deformation that acts as the source of residual stresses. Focused ion beam (FIB) milling used for nanoscale machining is accompanied by target material modification by ion beam damage having residual stress consequences that can be described in terms of eigenstrain. Due to the lack of direct means of experimental determination of residual stress or eigenstrain at the nanoscale we adopt a hybrid approach that consists of eigenstrain abstraction from molecular dynamics simulation, its application within a finite element simulation of a flexible silicon cantilever, and satisfactory comparison of the prediction with experimental observation. Directions for further enquiry are briefly discussed. ", keywords = Focused ion beam milling; Molecular dynamics; Eigenstrain; Residual stress, isbn = 0167-577X, doi=https://doi.org/10.1016/j.matlet.2016.08.111
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| 7. |
- Abbasi, Mazhar Ali, et al.
(författare)
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Fabrication of UV photo-detector based on coral reef like p-NiO/n-ZnO nanocomposite structures
- 2013
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Ingår i: Materials letters (General ed.). - : Elsevier. - 0167-577X .- 1873-4979. ; 108, s. 149-152
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Tidskriftsartikel (refereegranskat)abstract
- In this research work, a UV photo-detector is fabricated on fluorine doped tin oxide (FTO) glass substrate by exploiting the advantageous features of p-n heterojunctions based on p-NiO and n-ZnO composite nanostructures forming a coral-reef like structures. Scanning electron microscopy (SEM) and X-ray diffraction results showed uniform morphology and good crystal quality of the synthesised nanostructures respectively. I-V measurements have shown nonlinear and rectifying response of the p-NiO/n-ZnO heterojunction. The proposed photodiode exhibited excellent UV response with acceptable photocurrent generation of about 3.4 mA and the responsivity of 2.27 A/W at -3 biasing voltage.
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| 8. |
- Aboulfadl, Hisham, 1986, et al.
(författare)
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Atomic-scale characterization of diffusion kinetics in Ru/Al multilayer thin films
- 2019
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Ingår i: Materials Letters. - : Elsevier BV. - 1873-4979 .- 0167-577X. ; 254, s. 344-347
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Tidskriftsartikel (refereegranskat)abstract
- The microstructure properties of reactive multilayers play a key role in their chemical reactions. Ru/Al multilayers are investigated in as-deposited and annealed conditions using atom probe tomography to probe the interdiffusion and early phase formation. Performing atom probe analysis was accompanied with difficulties stemming from weak adhesion of the bi-layers and reconstruction artifacts. Nonetheless, it was possible to obtain valuable qualitative information concerning diffusion kinetics. Asymmetric interdiffusion during deposition is found. Grain boundary diffusion is shown to have a major contribution on enhancing mass-transport across the layers as well as on the nucleation and growth of the RuAl6 intermetallic phase.
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| 9. |
- Aboulfadl, Hisham, 1986, et al.
(författare)
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Interdiffusion in as-deposited Ni/Ti multilayer thin films analyzed by atom probe tomography
- 2019
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Ingår i: Materials Letters. - : Elsevier BV. - 1873-4979 .- 0167-577X. ; 236, s. 92-95
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Tidskriftsartikel (refereegranskat)abstract
- The nanoscale design of metallic multilayer thin films is one crucial factor that greatly influences the kinetics, often inducing unusual phase transformations. Metastable or amorphous phases may directly form in as-deposited films of certain thicknesses, which is common for Ni/Ti multilayers. Atom probe tomography and X-ray diffraction analyses are performed here to study the interdiffusion and structural changes as a function of the bilayer thickness in Ni/Ti multilayers. The films are deposited by DC magnetron sputtering with near 50:50 compositions. Multilayers with 5 nm bilayer thickness are found to be highly intermixed, with compositions up to ∼25 at.% for both diffuser metals, inducing amorphization reactions during deposition.
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| 10. |
- Afroze, Shammya, 1987, et al.
(författare)
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Insight of novel layered perovskite PrSrMn2O5+δ: A neutron powder diffraction study
- 2020
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Ingår i: Materials Letters. - : Elsevier BV. - 1873-4979 .- 0167-577X. ; 261
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Tidskriftsartikel (refereegranskat)abstract
- Neutron diffraction is very important to characterizing complex oxide materials, especially for the light element position and occupancy. In this study, a new layered perovskite oxide material, PrSrMn2O5+δ, was prepared by the solid-state reaction method and characterized by using X-ray and neutron powder diffraction, scanning electron microscopy and thermogravimetric analysis. X-ray diffraction data showed that the material adopted orthorhombic symmetry and Rietveld refinement of the neutron diffraction data gave accurate unit cell parameters (a = 3.8907 (1) Å, b = 3.8227 (1) Å, and c = 7.6846 (2) Å, atomic positions and space group (Pmmm)). Scanning electron microscopy showed a porous and interlinked microstructure. Thermogravimetric analysis exhibited two-stage weight losses up to 1000 °C from room temperature, indicating a good amount of oxygen losses and high material stability.
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