64 research outputs found
Strategies for implementing activity-based costing in the UK manufacturing industry
The purpose of this paper is to report the findings with a case study on why activity based costing lacks impact in the UK manufacturing industry. Activity based costing was performed on selected MT range subsystems of an electrical power generator to compare with the current UNN UK’s conven-tional costing system. The results have found that the current costing system works well for the MT products and thus change of costing system is not necessary for these products. The activity based costing system can be partially implemented in UNN UK for areas requiring detailed costing infor-mation such as new renewable products. Based on the result of the case study, this paper also high-lights the strategies need to be considered in order to adopt activity based costing within a typical manufacturing environment
Electrophoretic deposition of Ag nanoparticles into TiO2 nanotube arrays and their performance as photoanode of dye-sensitized solar cells
Dye-sensitized solar cells (DSSCs) are known as next-generation solar cells because their production process costs low and is environmentally friendly compared to silicon-type solar cells, which are currently most widely used in the world. However, power conversion efficiency (PCE) of DSSCs is still lower than 12%, which is much lower than that of silicon-type solar cells. Since one of the main reasons of such a low PCE of DSSCs is a weak light absorption ability of dye molecules, researchers have been studying to improve the light harvesting ability of DSSCs by, for instance, producing new dyes, designing new DSSC structures, adding light absorbing/scattering elements/materials, etc. The addition of metal nanoparticles (NPs) to an photoanode is one of the ways to improve light harvesting ability of DSSCs, because the NPs exhibit surface plasmon resonance (SPR) which absorb and scatter light strongly. SPR is a collective oscillation of free electrons of metal, thus strong electro-magnetic (EM) field is created near the surface of metal NPs. The electrons of dyes can be easily excited by the enhanced EM field and thus the PCE of DSSCs improved. However, the improvement of PCE of DSSCs by metal NPs is generally not as high as expected, because it is difficult to control dispersion state of metal NPs in an photoanode.
In this work, Ag NPs were used as metal NPs because Ag NPs are known to create the strongest EM field by SPR among all metals. Anodic TiO2 nanotube (TNT) arrays were employed as a photoanode since the morphology of TNT arrays is known to be appropriate to reduce an electrical resistivity at photoanode. Several methods of Ag NP deposition on TNT arrays were investigated for controlling the dispersion state of Ag NPs
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5′HS5 of the Human β-globin Locus Control Region Is Dispensable for the Formation of the β-globin Active Chromatin Hub
Hypersensitive site 5 (5′HS5) of the β-globin Locus Control Region functions as a developmental stage-specific border in erythroid cells. Here, we have analyzed the role of 5′HS5 in the three dimensional organization of the β-gene locus using the Chromatin Conformation Capture (3C) technique. The results show that when 5′HS5 is deleted from the locus, both remote and internal regulatory elements are still able to interact with each other in a three-dimensional configuration termed the Active Chromatin Hub. Thus, the absence of 5′HS5 does not have an appreciable effect on the three dimensional organization of the β-globin locus. This rules out models in which 5′HS5 nucleates interactions with remote and/or internal regulatory elements. We also determined the binding of CTCF, the only defined insulator protein in mammalian cells, to 5′HS5 by using chromatin immunoprecipitation (ChIP) assays. We detect low levels of CTCF binding to 5′HS5 in primitive erythroid cells, in which it functions as a border element. Surprisingly, we also observe binding levels of CTCF to 5′HS5 in definitive erythroid cells. Thus, binding of CTCF to 5′HS5 per se does not render it a functional border element. This is consistent with the previous data suggesting that CTCF has dual functionality
Preparation of BaTiO3 nanotube arrays, CoFe2O4 nanoparticles and their composite
Multiferroic nanocomposites which possess both ferroelectric and ferromagnetic properties are attracting much attention because of their scientific interest and significant technological promise in the novel multifunctional devices. Gas-phase syntheses have been typically used to fabricate multiferroic nanocomposites [1]; however, high production cost has been hindering further expansion of the research field. In this research, the components of multiferroic nanocomposites are fabricated by anodization and hydrothermal treatment which were then used to fabricate multiferroic nanocomposites through electrophoretic deposition (EPD) as cheaper alternatives to the costly gas-phase processes.
TiO2 nanotubes arrays were firstly formed on Ti metal foils by anodization in an electrolyte containing ethylene glycol, dimethyl sulfoxide, ammonium fluoride and water. Then, BaTiO3 nanotube arrays were obtained by hydrothermal treatment of TiO2 nanotube arrays using Ba-containing aqueous solution. The morphologies and crystal structure of BaTiO3 nanotube arrays were analyzed by a scanning electron microscope (SEM) and an X-ray diffractometer (XRD).
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Cloning and Characterization of the Autoinducer Synthase Gene from Lipid-Degrading Bacterium Cedecea neteri
Effects of cesium-substituted silicotungstic acid doped with polybenzimidazole membrane for the application of medium temperature polymer electrolyte fuel cells
Inorganic-organic composite membranes were prepared by using partly cesium-substituted silicotungstic acid (CHS-WSiA) and polybenzimidazole (PBI, MRS0810H) for medium temperature polymer electrolyte fuel cells (MT-PEFCs). Cesium hydrogen sulfate (CsHSO4, CHS) and silicotungstic acid (H4SiW12O40, WSiA) were milled to obtain 0.5CHS-0.5WSiA composites by dry and wet mechanical millings. N,Ndimethylacetamide (DMAc) was used as a disperse medium in the preparation of the inorganic solid acids by wet mechanical milling and also a casting agent for fabrication of membrane. Finally, flexible and homogeneous composite membranes with several phosphoric acid doping levels (PADLs) were obtained. The wet mechanical milling using DMAc was found to effectively promote good substitution of H+ ion in WSiA by Cs+ ion of CHS and promoted the formation of smaller grain sizes of composites, compared with dry milling. A high maximum power density of 378 mWcm-2 and a good constant current stability test were obtained from a single cell test using the PBI composite membrane containing 20 wt% of 0.5CHS-0.5WSiA from wet milling and phosphoric acid doping level (PADL) of 8 mol, at 150 °C under an anhydrous condition. Wet milling CHS-WSiA crystallites were highly dispersed in PBI to give homogenized membranes and played a significant role in the enhancemance of acidity by increasing the number of proton sites in the electrolyte membrane. After the addition of CHS-WSiA into PBI membrane, the acid and water retention properties were improved and incorporated as new proton conduction path by adsorbing phosphoric acid in these composite electrolyte membranes. These observations suggest that composite membranes with 8 mol of PADL are good promising PA dopedmembranes with effective electrochemical properties for the medium temperature fuel cells
Synthesis of MRGO nanocomposites as a potential photocatalytic demulsifier for crude oil-in-water emulsion
Oil-in-water (O/W) emulsion has been a major concern for the petroleum industry. A cost-effective magnetite-reduced graphene oxide (MRGO) nanocomposite was synthesized to study the demulsification process of emulsion using said nanocomposite under solar illumination. Characterization data show that the magnetite was successfully deposited on reduced graphene oxide through redox reaction at varying loading amounts of magnetite. Demulsification of the O/W emulsion using MRGO nanocomposite shows that in general the demulsification efficiency was dependent on the loading amount of Fe3 O4 on the RGO sheet. It was proposed that the surfactant hydroxyl groups have an affinity towards Fe3 O4, which the loading amount was directly proportionate to available active site in Fe3 O4. As the loading amount increases, charge recombination centers on the RGO sheet would increase, effectively affecting the charge distribution within MRGO structure
Riverine sustainment 2012
Student Integrated ProjectIncludes supplementary materialThis technical report analyzed the Navy's proposed Riverine Force (RF) structure and capabilities for 2012. The Riverine Sustainment 2012 Team (RST) examined the cost and performance of systems of systems which increased RF sustainment in logistically barren environments. RF sustainment was decomposed into its functional areas of supply, repair, and force protection. The functional and physical architectures were developed in parallel and were used to construct an operational architecture for the RF. The RST used mathematical, agent-based and queuing models to analyze various supply, repair and force protection system alternatives. Extraction of modeling data revealed several key insights. Waterborne heavy lift connectors such as the LCU-2000 are vital in the re-supply of the RF when it is operating up river in a non-permissive environment. Airborne heavy lift connectors such as the MV-22 were ineffective and dominated by the waterborne variants in the same environment. Increase in manpower and facilities did appreciable add to the operational availability of the RF. Mean supply response time was the biggest factor effecting operational availability and should be kept below 24 hours to maintain operational availability rates above 80%. Current mortar defenses proposed by the RF are insufficient.N
Examining the generalizability of research findings from archival data
This initiative examined systematically the extent to which a large set of archival research findings generalizes across contexts. We repeated the key analyses for 29 original strategic management effects in the same context (direct reproduction) as well as in 52 novel time periods and geographies; 45% of the reproductions returned results matching the original reports together with 55% of tests in different spans of years and 40% of tests in novel geographies. Some original findings were associated with multiple new tests. Reproducibility was the best predictor of generalizability—for the findings that proved directly reproducible, 84% emerged in other available time periods and 57% emerged in other geographies. Overall, only limited empirical evidence emerged for context sensitivity. In a forecasting survey, independent scientists were able to anticipate which effects would find support in tests in new samples
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