In this work, biomass growth is maintained just above maximum oxidative growth rate by regulating ethanol concentration in the fermenter. The state feedback linearizing control strategy is developed and applied to the technical scale fed-batch Tipifarnib mouse yeast fermentations. The proposed control algorithm is constructed on the reliable
state estimation algorithm developed previously and the biomass concentrations and ethanol measurements are then used in the control algorithm. The ethanol concentration is successfully controlled at fixed and time varying set values. By this approach the specific growth rate is controlled just over the critical value by regulating minimal ethanol concentration in order to maximize the biomass productivity. (C) 2010 Elsevier B.V. All rights reserved.”
“The transport behaviors of La0.5Ca0.5MnO3/LaMnO3/SrTiO3:Nb heterojunctions with a LaMnO3 layer thickness of between
0 and 12 nm have been systematically studied. The effect of the magnetic field on the junction without the buffer layer is weak. The influence of the magnetic field on the junction is maximized when the layer thickness is similar to 3 nm, demonstrated by a significant field-induced increase in current when the bias voltage is fixed. The corresponding magnetoresistance of the junction is negative, and its maximal value is similar to-32% for a field change of 5 T at 80 K. Based on a quantitative analysis of the current-voltage characteristics, the interfacial barrier can be derived, and it shows a complex variation with an increase in layer thickness, first decreasing and then increasing. This is GSI-IX the apparent reason for the change in buffer-layer-enhanced negative magnetoresistance of the junctions for different layer thicknesses. (C) 2011 American Institute of Physics. [doi:10.1063/1.3562916]“
“Trichoderma reesei and Aspergillus awamori enzymes were concentrated, pooled and assessed for the hydrolysis of steam-pretreated
sugarcane bagasse. The enzyme profile of T. reesei gave (IU/L): 1700 FPA, 20,000 CMCase, 340 beta-glucosidase and 12,600 xylanase. FPA and CMCase activities that were 4-fold higher than those of A. awamori (420 and 4900 IU/L, respectively). However the beta-glucosidase and xylanase activities PP2 cost were 134- and 6-fold lower than those of A. awamori (45,600 and 79,100 IU/L, respectively). Furthermore, A. awamori produced ferulic acid esterase (160 IU/L) which acts synergistically with cellulolytic-xylanolytic enzymes in the hydrolysis of lignocellulosic materials. The FPA and CMCase activities in the T. reesei-A. awamori blends were enhanced synergistically by 2-fold. Moreover, the hydrolytic effectiveness of the blends was superior to the use of unblended T. reesei or A. awamori enzymes, under corresponding conditions (10 FPU/g bagasse, 20 g bagasse/L and 50 degrees C). Hydrolysis experiments, presenting either 20 or 200 g/L bagasse, resulted in 3.9 or 40g glucose/L, respectively.