Studies of modified lithiated NiO cathode for low temperature solid oxide fuel cell with ceria-carbonate composite electrolyte

In this work, the effect of copper, iron and cobalt oxides on electrochemical properties of lithiated NiO cathodes was reported in low temperature solid oxide fuel cell (LT-SOFC) with ceria-carbonate composite electrolyte. The modified lithiated NiO cathodes were characterized by XRD, DC conductivity, SEM and electrochemical measurements. In spite of lower conductivities of modified cathodes, Li–Ni–M (M = Cu, Fe, Co) oxides with the order of Li–Ni–Co oxide > Li–Ni–Fe oxide > Li–Ni–Cu oxide, compared with that without modification, the catalytic activities of all the Li–Ni–M oxides were improved. In particularly, cobalt oxide modification favors both charge transfer and gas diffusion for O₂ reduction reaction as confirmed by AC impedance measurements. SEM micrographs show that grains aggregate with the modification of copper oxide or iron oxide, which may be responsible for the increased gas diffusion resistance. The results indicate that the lithiated NiO modified by cobalt oxide as cathode is an alternative to improve LT-SOFC performance with ceria-carbonate composite electrolyte.     

Controlled synthesis of bilayer graphene on nickel

ABSTRACT: We report uniform and low-defect synthesis of bilayer graphene on evaporated polycrystalline nickel films. We use atmospheric pressure chemical vapor deposition with ultra-fast substrate cooling after exposure to methane at 1000C. The optimized process parameters i.e. growth-time, annealing profile and flow rates of various gases are reported. By using Raman spectroscopy mapping, the ratio of 2D to G peak intensities (I2D/IG) is in the 0.9-1.6 range over 96 percent of 200umx200um area. Moreover, the average ratio of D to G peak intensities (ID/IG) is about 0.1.     

Probing the stabilizing role of C-terminal residues in trimethylamine dehydrogenase

In trimethylamine dehydrogenase, a homodimeric iron-sulfur flavoprotein, the C-terminal 17 residues of each subunit (residues 713- 729) embrace residues on the other subunit. The role of this unusual mode of interaction at the subunit interface was probed by isolating three mutant forms of trimethylamine dehydrogenase in which the C- terminus of the enzyme was deleted by five residues [delta(725-729], 10 residues [delta(720-729)] and 17 residues [delta(713-729)]. The solution properties and conformational states of the three mutant enzymes were investigated using optical, fluorescence and circular dichroism spectroscopies, ANS binding and a novel and conformationally sensitive hydrodynamic method. The data reveal that sequential deletion of the C-terminus of trimethylamine dehydrogenase does not affect significantly dimer stability or the overall structural integrity of the enzyme. However, deletion of the C-terminus severely compromises, but does not abolish, the ability of the enzyme to become covalently coupled with the redox cofactor FMN in the active site, located over 20 A from the C-terminus. Hydrodynamic studies reveal minor conformational changes in the deletion mutants that lead to a more compact enzyme structure. These conformational changes are probably transmitted to the active site via altering the interaction of the C-terminus with the second helix in the beta/alpha barrel of trimethylamine dehydrogenase, leading to poor flavinylation during the folding of the enzyme and assembly with FMN.      

Molecular memory with atomically smooth graphene contacts

We report the use of bilayer graphene as an atomically smooth contact for nanoscale devices. A two-terminal bucky-ball (C₆₀) based molecular memory is fabricated with bilayer graphene as a contact on the polycrystalline nickel electrode. Graphene provides an atomically smooth covering over an otherwise rough metal surface. The use of graphene additionally prohibits the electromigration of nickel into the C₆₀ layer. The devices exhibit a low-resistance state in the first sweep cycle and irreversibly switch to a high-resistance state at 0.8 to 1.2 V bias. In the subsequent cycles, the devices retain the high-resistance state, thus making it write-once read-many memory.     

Effect of processing technique on the transport and mechanical properties of graphite nanoplatelet/rubbery epoxy composites for thermal interface applications

Graphite nanoplatelet (GNP)/rubbery epoxy composites were fabricated by mechanical mixer (MM) and dual asymmetric centrifuge speed mixer (SM). The properties of the GNP/rubbery epoxy were compared with GNP/glassy epoxy composites. The thermal conductivity of GNP/rubbery epoxy composite (25 wt.% GNP, particle size 15 μm) reached 2.35 W m⁻¹ K⁻¹ compared to 0.1795 W m⁻¹ K⁻¹ for rubbery epoxy. Compared with GNP/rubbery epoxy composite, at 20 wt.%, GNP/glassy epoxy composite has a slightly lower thermal conductivity but an electrical conductivity that is 3 orders of magnitude higher. The viscosity of rubbery epoxy is 4 times lower than that of glassy epoxy and thus allows higher loading. The thermal and electrical conductivities of composites produced by MM are slightly higher than those produced by SM due to greater shearing of GNPs in MM, which results in better dispersed GNPs. Compression and hardness testing showed that GNPs increase the compressive strength of rubbery epoxy ∼2 times without significantly affecting the compressive strain and hardness. The GNP/glassy epoxy composites are 40 times stiffer than the GNP/rubbery epoxy composites. GNP/rubbery epoxy composites with their high thermal conductivity, low electrical conductivity, low viscosity before curing and high conformability are promising thermal interface materials.     

Prevalence of Salmonella infecting bacteriophages associated with Ontario pig farms and the holding area of a high capacity pork processing facility

BACKGROUND: There is interest in applying bacteriophages to control Salmonella in pig production and pork processing. The following reports on the prevalence of Salmonella infecting bacteriophages within Ontario pig farms and associated with the holding area of a pork slaughterhouse. RESULTS: Salmonella infecting bacteriophages were present in 30 and 28 of the effluent manure samples collected from 36 farms using S. Typhimurium DT104 or S. Heidelberg as host cell respectively. Bacteriophages were recovered in 95–100% of the 48 samples taken from holding pens within a high capacity slaughterhouse over a 12 month period. Bacteriophages isolated from farms exhibited similar host ranges which differed to that of slaughterhouse isolates. Salmonella (n = 21) from the slaughterhouse were susceptible to the endogenous bacteriophages. Despite being susceptible to the resident phages, the Salmonella populations were found to be genetically stable with the same genotypes being recovered over successive visits. Salmonella isolated from the farms were frequently resistant to the endogenous phages. CONCLUSIONS: Bacteriophages are prevalent in the pig slaughterhouse environment although they do not have a significant impact on the genetic structure of Salmonella populations. However, there was evidence that the Salmonella population structure on farms is influenced by the presence of infecting phages. Copyright © 2010 Society of Chemical Industry     

Automated Renal Cell Carcinoma Subtype Classification Using Morphological, Textural and Wavelets Based Features

We present a new image quantification and classification method for improved pathological diagnosis of human renal cell carcinoma. This method combines different feature extraction methodologies, and is designed to provide consistent clinical results even in the presence of tissue structural heterogeneities and data acquisition variations. The methodologies used for feature extraction include image morphological analysis, wavelet analysis and texture analysis, which are combined to develop a robust classification system based on a simple Bayesian classifier. We have achieved classification accuracies of about 90% with this heterogeneous dataset. The misclassified images are significantly different from the rest of images in their class and therefore cannot be attributed to weakness in the classification system.     

A knowledge creation info-structure to acquire and crystallize the tacit knowledge of health-care experts.

Tacit knowledge of health-care experts is an important source of experiential know-how, yet due to various operational and technical reasons, such health-care knowledge is not entirely harnessed and put into professional practice. Emerging knowledge-management (KM) solutions suggest strategies to acquire the seemingly intractable and nonarticulated tacit knowledge of health-care experts. This paper presents a KM methodology, together with its computational implementation, to 1) acquire the tacit knowledge possessed by health-care experts; 2) represent the acquired tacit health-care knowledge in a computational formalism--i.e., clinical scenarios--that allows the reuse of stored knowledge to acquire tacit knowledge; and 3) crystallize the acquired tacit knowledge so that it is validated for health-care decision-support and medical education systems.     

Multi-Performance Enhancement of Knitted Wool Fabric with Citric Acid: An Eco-Compatible Cross-Linker

Herein, we report an investigation on an eco-compatible cross-linker, citric acid, to enhance multi-performance characteristics of knitted wool fabric. Citric acid reduced relaxation shrinkage after multiple washings as well as enhanced easy-care performance. Mediation of formic acid as swelling agent further improved cross-linking behavior of citric acid for wool. Shrinkage of wool in course and wale direction after one and five washes were observed, and found that presence of the highest concentration lowered the shrinkage. In addition, crease recovery angle 297°, moisture management 0.675, better dye ability with reactive and acid dye as well as antibacterial activity were achieved at 2% formic acid and 15% citric acid concentrations.     

SDN-Enabled Content Dissemination Scheme for the Internet of Vehicles

The content-centric networking (CCN) architecture allows access to the content through name, instead of the physical location where the content is stored, which makes it a more robust and flexible content-based architecture. Nevertheless, in CCN, the broadcast nature of vehicles on the Internet of Vehicles (IoV) results in latency and network congestion. The IoV-based content distribution is an emerging concept in which all the vehicles are connected via the internet. Due to the high mobility of vehicles, however, IoV applications have different network requirements that differ from those of many other networks, posing new challenges. Considering this, a novel strategy mediator framework is presented in this paper for managing the network resources efficiently. Software-defined network (SDN) controller is deployed for improving the routing flexibility and facilitating in the inter-interoperability of heterogeneous devices within the network. Due to the limited memory of edge devices, the delectable bloom filters are used for caching and storage. Finally, the proposed scheme is compared with the existing variants for validating its effectiveness.