101,039 research outputs found
State Control of Interstate Air Pollution
Global warming is an unequivocal fact proved by the persistent rise of the average temperature of the earth. IPCC reported that scientists were more than 90 % certain that most of the global warming was caused by increasing concentrations of greenhouse gases (GHG) produced by human activities. One alternative to combat the GHG is to explore technologies for utilizing CO2 already generated by current energy systems and develop methods to convert CO2 into useful combustible gases. Two-step conversion of CO2 with catalysts is one of the most promising methods. Ceria (CeO2) is chosen as the main catalyst for this conversion in the thesis. It releases O2 when it is reduced in a heating process, and then absorbs O2 from CO2 to produce CO when it is re-oxidized in a cooling process. To make the conversion economic, solar power is employed to drive the conversion system. In this thesis, a flexible system with fluidized bed reactors (FBRs) is introduced. The thermogravimetric analysis (TGA) was carried out to examine the performance of ceria during its reduction and oxidation. Subsequently, the exergy analysis was used to evaluate the systemâs capability on exporting work. The theoretical fuel to chemical efficiency varied from 4.85 % to 43.2 % for CO2 conversions. To investigate the operation mechanism of the system, a mathematical model was built up for the dynamic simulation of the system. Variables such as temperatures and efficiencies were calculated and recorded for different cases. The optimum working condition was found out to be at 1300 â°C for the commercial type of ceria. Finally, an experimental system was set up. The hydrodynamics and heat transfer in the fluidized bed reactor were studied. A CFD model was built up and validated with the experimental trials around 120 â°C. The model was then used as a reliable tool for the optimization of the reactor. The entire work in the thesis follows the procedure of developing an engineering system. It forms a solid basis for further improvements of the system to recycle CO2.QC 20141006</p
Taste-Masking: Function of Exaggerated Prandial Drinking in Desalivate Mice
Taste thresholds for the bitter compound sucrose octaacetate (SOA) were elevated by desalivation in mice. Thresholds were determined for control and experimental animals both before and after ligation of all salivary ducts. There was a significant increase in SOA thresholds in the desalivate mice, and the pre- to post-operative differences in threshold between the control and experimental groups were significant. The altered response to SOA by desalivate mice is shown to be due to the assumption of a prandial pattern of drinking as a result of desalivation. This conclusion is based on experiments with wet mash which failed to show any differences in threshold between the same control and desalivate mice that demonstrated a significant difference when tested on fluids and dry pellets
Role of Olfaction in Taste-Aversion to PTC in Mice
The objective of most taste research involving choice is to eliminate from the experiment all cues to the animal except those that are strictly gustatory. Among those potentially confounding cues, one of the most obvious is olfaction, although it often remains uncontrolled in taste experiments. The present report clearly demonstrates the role played by olfaction in a discrimination experiment with C57B1/6 and CFW mice as regards their response to phenylthiocarbamide (PTC) when paired with water. The results have implications for conclusions drawn by other investigators who have attributed differences in PTC sensitivity in mice to taste alone
Communities Working for Better Schools
This report is a call to action for community organizations, reformers, and funders to ensure that communities have the information and resources to create sustainable school and community partnerships that result in high-quality, equitable education for all students
Effect of solid propellant rocket exhaust impingement on spacecraft materials Final report, 18 Mar. 1966 - 21 Feb. 1969
Solid propellant rocket exhaust impingement effect on spacecraft material
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