An analytical approach to integral resonant control of second-order systems

Peer reviewedPostprin

Unlocking Efficiency in Radio-Frequency Heating : Eigenfrequency Analysis for Resonance Identification and Propagation Enhancement in Nigerian Tar Sands

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A dual-loop tracking control approach to precise nanopositioning

The author(s) received no financial support for the research, authorship, and/or publication of this article.Peer reviewedPostprin

Oxidation of porous stainless steel supports for metal-supported solid oxide fuel cells

Oxidation behavior of porous P434L ferritic stainless steel, used for the fabrication of metal-supported solid oxide fuel cells (MS-SOFC), is studied under anodic and cathodic atmospheres. Temperature- and atmosphere-dependence is determined for as-sintered and pre-oxidized stainless steel. Pre-oxidation reduced the long-term oxidation rate. For pre-oxidized samples, the oxidation rate in air exceeds that in humid hydrogen for temperatures above 700 °C. The influence of PrOx, LSCF-SDC, and Ni-SDC coatings is also examined. The coatings do not dramatically impact oxide scale growth. Oxidation in C-free and C-containing anodic atmospheres is similar. Addition of CO2, CH4, and CO to humidified hydrogen to simulate ethanol reformate does not significantly impact oxidation behavior. Cr transpiration in humid air is greatly reduced by the PrOx coating, and a PrCrO3 reaction product is observed throughout the porous structure. A dense and protective chromia-based scale forms on steel samples during oxidation in all conditions. A thin silica enriched oxide layer also forms at the metal-scale interface. In general, the oxidation behavior at 700 °C is found to be acceptable

Oxidation of porous stainless steel supports for metal-supported solid oxide fuel cells

Oxidation behavior of porous P434L ferritic stainless steel, used for the fabrication of metal-supported solid oxide fuel cells (MS-SOFC), is studied under anodic and cathodic atmospheres. Temperature- and atmosphere-dependence is determined for as-sintered and pre-oxidized stainless steel. Pre-oxidation reduced the long-term oxidation rate. For pre-oxidized samples, the oxidation rate in air exceeds that in humid hydrogen for temperatures above 700 °C. The influence of PrOx, LSCF-SDC, and Ni-SDC coatings is also examined. The coatings do not dramatically impact oxide scale growth. Oxidation in C-free and C-containing anodic atmospheres is similar. Addition of CO2, CH4, and CO to humidified hydrogen to simulate ethanol reformate does not significantly impact oxidation behavior. Cr transpiration in humid air is greatly reduced by the PrOx coating, and a PrCrO3 reaction product is observed throughout the porous structure. A dense and protective chromia-based scale forms on steel samples during oxidation in all conditions. A thin silica enriched oxide layer also forms at the metal-scale interface. In general, the oxidation behavior at 700 °C is found to be acceptable

Cloning and sequencing of a gene encoding a novel extracellular neutral proteinase from Streptomyces sp. strain C5 and expression of the gene in Streptomyces lividans 1326.

The gene encoding a novel milk protein-hydrolyzing proteinase was cloned on a 6.56-kb SstI fragment from Streptomyces sp. strain C5 genomic DNA into Streptomyces lividans 1326 by using the plasmid vector pIJ702. The gene encoding the small neutral proteinase (snpA) was located within a 2.6-kb BamHI-SstI restriction fragment that was partially sequenced. The molecular mass of the deduced amino acid sequence of the mature protein was determined to be 15,740, which corresponds very closely with the relative molecular mass of the purified protein (15,500) determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The N-terminal amino acid sequence of the purified neutral proteinase was determined, and the DNA encoding this sequence was found to be located within the sequenced DNA. The deduced amino acid sequence contains a conserved zinc binding site, although secondary ligand binding and active sites typical of thermolysinlike metalloproteinases are absent. The combination of its small size, deduced amino acid sequence, and substrate and inhibition profile indicate that snpA encodes a novel neutral proteinase

The Counter Electrode Impact on Quantum Dot Solar Cell Efficiencies

The counter electrode (CE), despite being as relevant as the photoanode in a quantum dot solar cell (QDSC), has hard-ly received the scientific attention it deserves. In this study, nine CEs: single walled carbon nanotubes (SWCNTs), tungsten oxide (WO3), poly(3,4-ethylenedioxythiophene) (PEDOT), copper sulfide (Cu2S), candle soot, functionalized multiwalled carbon nanotubes ( F- MWCNTs), reduced tungsten oxide (WO3-x), carbon fabric (C-Fabric), and C-Fabric/WO3-x were prepared by using low cost components and facile procedures. QDSCs were fabricated with a TiO2/CdS film which served as a common photoanode for all CEs. The power conversion efficiencies (PCEs) were: 2.02, 2.1, 2.79, 2.88, 2.95, 3.78, 3.66, 3.96, and 4.6 % respectively, and the incident photon to current conversion efficiency re-sponse was also found to complement the PCE response. Among all CEs employed here, the C-Fabric/WO3-x outper-forms all the other CEs, for the synergy between C-Fabric and WO3-x comes to the fore during cell operation. The (i) low sheet resistance of C-Fabric, and its’ high surface area due to the mesh like morphology, enables high WO3-x load-ing during electrodeposition, and (ii) the good electrocatalytic activity of WO3-x, the very low overpotential and its high electrical conductivity that facilitate electron transfer to the electrolyte, are responsible for the superior PCE. WO3 based electrodes have not been used till date in QDSCs; the ease of fabrication of WO3 films, and their good chem-ical stability and scalability also favor their application to QDSCs. Futuristic possibilities for other novel composite CEs are also discussed. We anticipate this study to be useful for a well-rounded development of high performance QDSCs