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Due to various concerns involving conventional gasoline, there has been a growing interest in the study of alternative fuels and their use in the automotive industry. There has been particular interest in the fuel effects of varying levels of ethanol blends and other alternative fuels on vehicle emissions and fuel economy. This paper will examine and compare both exhaust emissions and fuel economy for various ethanol blended fuels, and a 16 % butanol blended fuel. The results were generated using the U.S. Federal Test Procedure. Vehicles that are certified to U.S., European, and Brazilian government standards were tested. These vehicles include a flex fuel capable (FFV) 2007 Chevrolet Zafira (E100-FFV), 2007 Chevrolet Suburban (E85-FFV), 2007 Saab 9-5 BioPower (E85-FFV), 2007 Chevrolet Suburban, 2007 Pontiac G5, and a 2006 Pontiac G6. The fuels examined were E10, E20, E85, and Bu16. Each fuel was splash blended to make up the proper finished fuel blend. Fuel economy and emissions results from these fuels were compared with those from Tier 2 Emissions Certification fuel.

The potential use of vegetable oil derived industrial oils continues to be of great interest because vegetable oils are relatively non-toxic, biodegradable, and a sustainably produced basestock alternative to petroleum oil, a non-renewable basestock. For the conservation of the environment, bio-mass materials, such as vegetable oils, are desirable as substitutes for petroleum oil in heat treatment. Therefore, it is expected that these basestock materials will continue to be of increasing interest in the heat treatment industry. However, the fatty ester components containing conjugated double bonds of the triglyceride structure of vegetable oils typically produce considerably poorer thermal oxidative stability than that achievable with petroleum basestocks under typical use conditions. This is especially true when a vegetable oil is held in an open tank with agitation and exposure to air at elevated temperatures for extended periods of time (months or years). Furthermore, when used as quenchants, furnace loads of hot steel (850 °C) are typically rapidly immersed and cooled to approximately 50 °C to 60 °C bath temperatures for steel hardening applications. Clearly, for this application, reasonable thermal-oxidative stability is essential. This paper reviews the work completed thus far in screening various vegetable oils as potential steel quenchants both with and without antioxidants. Particular focus is placed, where possible, on comparing pressure differential scanning calorimetry as a potential screening method with the more commonly used (for this application) modified Indiana Stirring Oxidation Test. In addition, the general impact of oxidation on the quenching performance of the better vegetable oil candidates is shown.

Experiments on immobilization of cellulase complex (cellulase, Novozymes) and enzyme complex (cellulases and hemicellulases, Novozymes) were performed on porous Siran™ beads using covalent and non-covalent bonding methods. Free enzyme complex was used for hydrolyzing various pretreated biomass such as corn stover, distillers dried grain with solubles, switch grass and blue stem grass. Maximum activity of enzyme complex was found with corn stover and was used as a substrate for measuring cellulase and hemicellulases activities. Protein loading for immobilized cellulase complex and enzyme complex on Siran™ carriers was found in the range of 10.776–18.000 % and 19.932–23.082 %, respectively. Activity loading for immobilized cellulase complex with avicel was in the range of 16.610–22.026 %. For enzyme complex, activity loading was found in the range of 43.558–61.222 %, 8.274–19.124 %, and 7.180–14.114 % with avicel, xylan, and corn stover as substrates, respectively. Recycling experiments for immobilized cellulase complex and enzyme complex were carried out using various substrates, and the residual enzyme activity was measured after the third cycle. Carbodiimide bonded cellulase complex retained more residual enzyme activity with avicel (49.460 %), which indicates a good cross linker for cellulase immobilization. The enzyme complex bonded to carbodiimide, and glutaraldehyde retained residual activity of 44.160 % with xylan and 73.230 % with corn stover, respectively. Recycling studies showed greater retention in residual enzyme activity with covalent bonded enzymes than non-covalent bonded enzymes. Glutaraldehyde and carbodiimide were found to be effective cross linkers for immobilizing both cellulase and hemicellulases in covalent bonding method.

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