Abstract: Methods and systems are provided for improving fuel usage while addressing knock by adjusting the use of spark retard and direct injection of a knock control fluid based on engine operating conditions and the composition of the injected fluid. One or more engine parameters, such as EGR, VCT, boost, throttle position, and CMCV, are coordinated with the direct injection to reduce torque and EGR transients.

Abstract: A fuel compensation factor (FCF) is determined to account for the amount of oxygenated fuel blended in diesel fuel. In one embodiment, the FCF is based on an expected exhaust gas oxygen concentration compared to an actual exhaust gas oxygen concentration. The FCF is used to estimate an amount of oxygenated fuel in the blend. Such estimate can be used to adjust the exhaust temperature model, which is used at least in determining the temperature in aftertreatment devices, the fuel dilution model which affects oil change recommendations, and the diesel particulate filter loading model which affects regenerations. Biodiesels are more prone to waxing at lower temperatures. The estimated amount of biodiesel and the temperature in the injection system are used to prevent and/or delay starting when it is predicted that too much wax exists in the fuel system.

Abstract: Methods and systems are provided for improving fuel usage while addressing knock by adjusting the use of spark retard and direct injection of a knock control fluid based on engine operating conditions and the composition of the injected fluid. One or more engine parameters, such as EGR, VCT, boost, throttle position, and CMCV, are coordinated with the direct injection to reduce torque and EGR transients.

Abstract: A fuel compensation factor (FCF) is determined to account for the amount of oxygenated fuel blended in diesel fuel. In one embodiment, the FCF is based on an expected exhaust gas oxygen concentration compared to an actual exhaust gas oxygen concentration. The FCF is used to estimate an amount of oxygenated fuel in the blend. Such estimate can be used to adjust the exhaust temperature model, which is used at least in determining the temperature in aftertreatment devices, the fuel dilution model which affects oil change recommendations, and the diesel particulate filter loading model which affects regenerations. Biodiesels are more prone to waxing at lower temperatures. The estimated amount of biodiesel and the temperature in the injection system are used to prevent and/or delay starting when it is predicted that too much wax exists in the fuel system.

Abstract: Methods for analyzing, selecting, characterizing or classifying compositions of a co-polymer, e.g., glatiramer acetate are described. The methods entail analysis of pyro-glutamate in the composition, and, in some methods, comparing the amount of pyro-glutamate present in a composition to a reference standard.

Abstract: Methods for analyzing, selecting, characterizing or classifying compositions of a co-polymer, e.g., glatiramer acetate are described. The methods entail analysis of pyro-glutamate in the composition, and, in some methods, comparing the amount of pyro-glutamate present in a composition to a reference standard.

Abstract: Methods for analyzing, selecting, characterizing or classifying compositions of a co-polymer, e.g., glatiramer acetate are described. The methods entail analysis of pyro-glutamate in the composition, and, in some methods, comparing the amount of pyro-glutamate present in a composition to a reference standard. In some cases, the methods entail treating the co-polymer with pyro-glutamate aminopeptidase to cleave N-terminal pyro-glutamate residues.