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The first commercially available plug-in hybrid electric vehicle (PHEV), the General Motors (GM) Volt, was introduced into the market in mid-December 2010. The Volt uses a series-split powertrain architecture, which provides benefits over the series architecture that typically has been considered for use in electric-range extended vehicles (EREVs). A specialized EREV powertrain, called the Voltec, drives the Volt through its entire range of speed and acceleration with battery power alone and within the limit of battery energy, thereby displacing more fuel with electricity than a PHEV, which characteristically blends electric and engine power together during driving. This paper assesses the benefits and drawbacks of these two different plug-in hybrid electric architectures (series versus series-split) by comparing component sizes, system efficiency, and fuel consumption over urban and highway drive cycles.

In this paper we present the results of full-scale chassis dynamometer testing of two hybrid transit bus configurations, parallel and series and, in addition, quantify the impact of air conditioning. We also study the impact of using an electrically controlled cooling fan. The main trend that is noted, and perhaps expected, is that a significant fuel penalty is encountered during operation with air conditioning, ranging from 17-27% for the four buses considered. The testing shows that the series hybrid architecture is more efficient than the parallel hybrid in improving fuel economy during urban, low speed stop and go transit bus applications. In addition, smart cooling systems, such as the electrically controlled cooling fan can show a fuel economy benefit especially during high AC (or other increased engine load) conditions.

A one-dimensional two-phase model of an adsorptive catalytic monolith reactor is used to analyze the Lean NOx Trap (LNT). The model simulates the features of NOx storage and reduction (NSR), a periodic process involving the sequential trapping on a storage component and conversion of NOx to nitrogen on a precious metal catalyst under lean conditions found in the exhaust of lean burn and diesel vehicles. A detailed storage kinetic model is used for the simulations. The NOx storage phase on Pt/BaO/Alumina catalyst has been studied in detail with particular attention to the effect of fluid velocity, storage time and storage component loading. The reductive phase is also analyzed. The simulated results are compared with our lab experimental data. The model predictions are in good agreement with the experimental observations and trends reported in the literature.

Membranes are highly desirable for separating gases in life-support applications. They are small, light, efficient, selective and require little operational or physical maintenance. Facilitated transport membranes have particularly high flux and selectivity. We created enzyme-based facilitated transport membranes using isozymes and mutants as immobilized arrays alone and in conjunction with polymeric membranes. The enzyme operates efficiently at the low CO2 concentrations encountered in respiratory gases and can bring CO2 to near ambient levels. CO2 flux is greatly enhanced and selectivities for CO2 over O2 of 200:1 or greater are possible. The enzymes are robust and stable for long periods under a variety of storage and use conditions.

In preparation for the 21st Century, NASA Johnson Space Center is designing and building a habitat (Bio-Plex) intended for use in long duration missions where all life support systems will be recycled and reused. Crops grown on-board will be used for air and water recycling and also serve as a food source. Space food development for Bio-Plex marks a departure from previous NASA missions yet some basic principles still apply. The differences and similarities will be discussed. The United States space food program has progressed from tubes and cubes in the earlier years to eating familiar food from open containers using normal utensils. All space food development problems include weight and volume restrictions, nutrition, crew acceptability and consumption, and management of food generated waste. To date, food for spaceflight has been carried onboard or delivered in space. Preparation has been limited to rehydration and heating to serving temperature.

This research focused on the testing of the original potable water processor aboard Space Station Freedom that was to produce potable water from the humidity condensate and additional water generated by carbon dioxide reduction. Humidity condensate was simulated by an influent water model “Ersatz.” The humidity condensate was treated with multifiltration (MF) beds that consisted of a train of sorption beds (referred to as “Unibed”) designed to remove specific contaminants. For the complete simulated MF system runs tested for 100 bed volumes (BV) (volume processed/total column volume), 0.6% of the TOC was removed by the SAC/IRN 77 (Strong Acid Cation exchange resin), 39.6% of the total organic carbon (TOC) was removed by the WBA/IRA 68 (Weak Base Anion exchange resin), 13.2% of the TOC was removed by activated carbon adsorption (580-26), and the remaining sorbent media acted as polishing units to remove an additional 1.6% of the TOC at steady state.