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82.
This paper investigates the benefits that the partial least squares (PLS) modelling approach offers engineers involved in the operation of fed-batch fermentation processes. It is shown that models developed using PLS can be used to provide accurate inference of quality variables that are difficult to measure on-line, such as biomass concentration. It is further shown that this model can be used to provide fault detection and isolation capabilities and that it can be integrated within a standard model predictive control framework to regulate the growth of biomass within the fermenter. This model predictive controller is shown to provide its own monitoring capabilities that can be used to identify faults within the process and also within the controller itself. Finally it is demonstrated that the performance of the controller can be maintained in the presence of fault conditions within the process. 相似文献
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The hot corrosion of alloys comprises a complex series of interacting processes. Despite the difficulties involved, the thermodynamic analysis of corrosion ought to take into account the multicomponent nature of the alloy, the constitution of the gas, and the microenvironments present in the corrosion layer. Most importantly the metallic, oxide, sulphide, and salt phases ought to be treated as solutions (mixtures). The methods for assessment and calculations involving solution phases are demonstrated by reference to the salt system NaCl-NaOH-Na2CrO4-Na2S04 and its equilibrium with Cr2O3 as the protect!ve oxide layer and the gaseous combustion products. The data requirements assa.ciated with these developments and their possible application to kinetic analysis are discussed. 相似文献
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Nancy J. McGraw Nida Napawan Mitchell R. Toland John Schulze Barry M. Tulk Elaine S. Krul 《Journal of food science》2014,79(9):H1832-H1840
Consumption of protein hydrolysates has been proposed to stimulate muscle anabolism more than intact (nonhydrolyzed) proteins via accelerated delivery of amino acids for muscle protein synthesis (MPS). We evaluated whether the rate of amino acid uptake and transport across intestinal cells was enhanced for soy protein hydrolysates versus nonhydrolyzed soy protein. Intact and partially hydrolyzed proteins were subject to simulated gut digestion and applied to the apical surface of Caco‐2 monolayers. Basolateral media was harvested after 3 h and quantitatively analyzed for free amino acids using ion‐exchange chromatography and comparison to an included reference standard. Basolateral concentrations of all amino acids were higher (mean 32%) for hydrolyzed versus nonhydrolyzed protein with the greatest differences in histidine, lysine, and valine. Scale‐up production of the soy protein hydrolysate did not diminish its enhanced absorption properties. These data support the hypothesis that hydrolyzed soy protein may provide dietary amino acids that are more rapidly transported across the intestinal epithelium versus intact soy protein. This would be important under conditions where rapid and increased levels of amino acids are needed such as in the stimulation of MPS. 相似文献
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Andre Matthew Loyd Roger W. Nightingale Yin Song Jason F. Luck Hattie Cutcliffe Barry S. Myers Cameron ‘Dale’ Bass 《Accident; analysis and prevention》2014
Given the high incidence of TBI, head injury has been studied extensively using both cadavers and anthropomorphic test devices (ATDs). However, few studies have benchmarked the response of ATD heads against human data. Hence, the objective of this study is to investigate the response of adult and ATD heads in impact, and to compare adult Hybrid III head responses to the adult head responses. 相似文献
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Clare Robinson D.A. Barry Irina Kouznetsova 《The Science of the total environment》2009,407(16):4560-4573
Enhanced reductive dehalogenation is an attractive treatment technology for in situ remediation of chlorinated solvent DNAPL source areas. Reductive dehalogenation is an acid-forming process with hydrochloric acid and also organic acids from fermentation of the electron donors typically building up in the source zone during remediation. This can lead to groundwater acidification thereby inhibiting the activity of dehalogenating microorganisms. Where the soils' natural buffering capacity is likely to be exceeded, the addition of an external source of alkalinity is needed to ensure sustained dehalogenation. To assist in the design of bioremediation systems, an abiotic geochemical model was developed to provide insight into the processes influencing the groundwater acidity as dehalogenation proceeds, and to predict the amount of bicarbonate required to maintain the pH at a suitable level for dehalogenating bacteria (i.e., > 6.5). The model accounts for the amount of chlorinated solvent degraded, site water chemistry, electron donor, alternative terminal electron-accepting processes, gas release and soil mineralogy. While calcite and iron oxides were shown to be the key minerals influencing the soil's buffering capacity, for the extensive dehalogenation likely to occur in a DNAPL source zone, significant bicarbonate addition may be necessary even in soils that are naturally well buffered. Results indicated that the bicarbonate requirement strongly depends on the electron donor used and availability of competing electron acceptors (e.g., sulfate, iron (III)). Based on understanding gained from this model, a simplified model was developed for calculating a preliminary design estimate of the bicarbonate addition required to control the pH for user-specified operating conditions. 相似文献