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Showing 1 to 20 of 128 for “"VFA"”.
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The Effects Of Ph On Enhanced Biological Phosphorus Removal (ebpr) With Propionic Acid As The Dominant Volatile Fatty Acid (vfa)
pH control is a tool to improve some aspects of Enhanced Biological Phosphorus Removal (EBPR) process. Filipe et al (2001a, 2001b, and 2001c) found strong evidence that the stability of EBPR systems can be improved by increasing the pH of the anaerobic zone, thereby creating conditions where …
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Volatile Fatty Acid Production in Ruminants
Volatile fatty acids (VFA) are important products of ruminal fermentation. The VFA are not only the major source of energy to the ruminant animals but also influence methane production in the rumen. Therefore it is important to understand mechanism controlling VFA production and to depict VFA …
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Biorefining Sewage for Energy and Green Chemicals
… of AD, biohydrogen and volatile fatty acids (VFAs) are produced which are gaining increased attention due to their higher energy density and higher market value, respectively.<br/><br/>For their production to be adopted at industrial scale however, the yields of biohydrogen and VFAs need to be …
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EVALUATION OF A METHOD TO MEASURE VOLATILE FATTY ACIDS AND GASES IN VITRO WITH MATHEMATICAL MODELING
… linked with volatile fatty acid (VFA) profiles in ruminant animals. For example, a shift from acetate to propionate may decrease carbon dioxide (CO2) and hydrogen (H2) production, and in turn, decrease conversion of CO2 and H2 to methane. In vitro methods have been developed to …
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Adaptive output-feedback control and applications to Very Flexible Aircraft
Very Flexible Aircraft (VFA) corresponds to an aerial platform whose flight dynamics critically depends on its flexible wing shape, and has been investigated as a potential solution to generate high-altitude low-endurance flights. The dominant presence of model uncertainties and potential actuator …
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Sensor Technologies for Nutritional Management of Ruminants
… to monitor ruminal volatile fatty acid (VFA) concentrations using pH sensing. Four ruminally cannulated Holstein cows at maintenance were included in a Latin Square Design. Treatments consisted of a) chopped grass hay, b) 85% chopped grass hay and 15% cracked corn and soybean meal, c) 70% …
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A Bioelectrochemical Sensing System for Measuring Acidic Bioprocess Fermentation End Products
… gas composition and volatile fatty acids (VFAs) concentration. To date the most reliable methods for offline VFA measurement are gas chromatography (GC) and high performance liquid chromatography (HPLC). Attempts have been made to develop in situ enzyme based sensor for online VFA …
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Integration of Ruminal Volatile Fatty Acid Production Methods, Ruminal Fluid Sampling Techniques, and Mathematical Modeling
… the rate of ruminal volatile fatty acid (VFA) production and a practical but effective way of sampling ruminal fluid. In experiment 1, an in vitro technique (procedure and mathematical approach) were developed to estimate ruminal VFA production in vivo. This method provides a practical …
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Characterization and application of vortex flow adsorption for simplification of biochemical product downstream processing
… a novel unit operation, vortex flow adsorption (VFA), is created. In VFA, the rotation of the inner cylinder facilitates the fluidization of the adsorbent resin. In addition, VFA has high fluid voidage so that it can be used to recover biochemical products directly from fermentation broths or …
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Effect of feeding fumaric or citric acid on weanling pig performance and selected intestinal digesta measurements at varying times postweaning
… digesta pH, chloride ion concentration (Cl-), VFA profile and microflora populations was studied. In study 1, feeding citric acid improved ADG and feed conversion (F:G), whereas fumaric acid only numerically improved ADG and F:G. No significant dietary effect on intestinal pH, Cl- or VFA …
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The Investigation of Nitrite Accumulation and Biological Phosphorus Removal in an Intermittently Aerated Process Combining Shortcut Nitrogen Removal and Sidestream Biological Phosphorus Removal
… (SBPR) and an A-stage WAS fermenter that feeds VFA into the SBPR (the supernatant of the fermenter is called fermentate) were implemented in order to enhance biological phosphorus removal. About 8 months after the RAS and WAS fermenter implementation, there was a 28 day consecutive period of low …
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Harnessing <i>Haloferax mediterranei</i> for Bioplastic Production from Organic Waste
… and the needs for efficient volatile fatty acid (VFA) generation. Then, ex-situ VFA recovery from digestate was experimentally evaluated using hydrophobic deep eutectic solvents with omniphobic membranes, and kinetic-affinity relationships guided the separation design. To bypass VFA purification …
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Alternative Analytical and Experimental Procedures to Explore Rumen Fermentation as Driven by Nutrient Supplies
… and to estimate rumen volatile fatty acid (VFA) dynamics under different nutrient supplies. The objective of the first study was to explore the strengths and limitations of mixed-model meta-analysis, recursive feature elimination (RFE), and additive Bayesian networking (ABN) in identifying …
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Anaerobic Digestion of Separated Cattle Slurry
… the degraded solids were attributed to lipids, VFA and crude protein. These differences accounted for the higher gas yield (per VS destroyed) and richer quality of biogas from SCS, and the more rapid fall in the gas yield from WCS as the retention time was dropped. A third factor, particle size …
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Enhanced Biological Phosphorus Removal from Dairy Manure to Meet Nitrogen:Phosphorus Crop Nutrient Requirements
… The fermentation potential (volatile fatty acid (VFA) production) of dairy manure was determined through laboratory analysis to be 15.3% of the total COD. Total VFA production was composed of 57, 23, and 20% acetic, propionic, and butyric acids, respectively. The EBPR component of the BioWin …
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Defining effective fiber content of dairy rations
… balance (NB), rumen volatile fatty acids (VFA), and rumen fluid (RFD) and solids (RSD) dilution rates. DMI was highest for added fiber rations and higher for CSH than hay rations. Digestibility of DM was depressed for added fiber rations with lowest for CSH. Most favorable NB was for CSH …
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GENERATING BIOENERGY AND HIGH-VALUE PRODUCTS FROM HIGH SALINITY FOOD WASTE
Bioenergy generation and volatile fatty acids (VFAs) production from household food waste and high salinity food processing waste were explored using anaerobic digestion and dark fermentation processes, respectively. This study tested adding value to three organic waste streams: household food …
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Evaluation Of Prefermentation As A Unit Process Upon Biological Nutrient Removal Including Biokinetic And Wastewater Parameters
… wastewater occurred even when all additional VFA production exceeded VFA requirements using typical design criteria (e.g. 6 g VFA per 1 g P removal). • Prefermentation increased RBCOD content by an average of 28.8% and VFA content by an average of 18.8%, even for a septic domestic wastewater. …
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Evaluation of in vitro and in vivo equine microbial population shifts in response to colic conditions
… in order to investigate treatment effects on VFA and NH3 concentration, and pH following starvation or starch overload. This research indicated that total volatile fatty acid (VFA) concentration may be affected by treatment following starch overload. Additionally, branched chain VFA, and …
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The effect of operational and environmental parameters on the acid-phase anaerobic digestion of primary sludge
… and lipids) to short-chain volatile fatty acids (VFAs) and other soluble end-products. The experiments were conducted using two continuous-flow three-liter reactors having different configurations: a completely mixed reactor (CMR) with a clarifier and sludge recycle, and an upflow anaerobic sludge …
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