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Engineering Commons™

Open Access. Powered by Scholars. Published by Universities.®

1998

University of Nebraska - Lincoln

Biomedical Engineering and Bioengineering

Articles 1 - 8 of 8

Full-Text Articles in Engineering

A Continuous Process For The Conversion Of Vegetable Oils Into Methyl Esters Of Fatty Acids, Hossein Noureddini, D Harkey, V Medikonduru Dec 1998

A Continuous Process For The Conversion Of Vegetable Oils Into Methyl Esters Of Fatty Acids, Hossein Noureddini, D Harkey, V Medikonduru

Papers in Biomaterials

A continuous process for the transesterification of triglycerides to methyl esters was investigated in a pilot plant. The process was equipped with a motionless and a high-shear mixer. The experimental studies explored variations in the mixing intensity, stoichiometry, and catalyst concentration on the overall conversion. The combined as well as individual effect of mixers was examined. The developed process resulted in high conversions of vegetable oils into methyl esters. Conversion of triglycerides to methyl esters in excess of 98% was achieved. Larger excess amounts of alcohol favored higher conversions. The motionless and high-shear mixers each provided adequate mixing for the …

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Enzymatic Glycerolysis Of Soybean Oil , Hossein Noureddini, S E. Harmeier Oct 1998

Enzymatic Glycerolysis Of Soybean Oil , Hossein Noureddini, S E. Harmeier

Papers in Biomaterials

Enzymatic glycerolysis of soybean oil was studied. Of the nine lipases that were tested in the initial screening, Pseudomonas sp. resulted in the highest yield of monoglycerides. Lipase from Pseudomonas sp. was further studied for the influence of temperature, thermal stability, enzyme/oil ratio, and glycerol/oil ratio. A full factorial optimization approach was performed. The following conditions were tested over the specified ranges: temperature (30?70°C), thermal stability (30?70°C), enzyme/oil ratio (0.05?0.2 g enzyme/10 g oil), glycerol/oil ratio (1:1?3:1 glycerol/oil molar ratio) and 1 h reaction time. The stability of the enzyme at the reaction temperature was also incorporated as a separate …

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Runoff And Erosion Following Field Application Of Beef Cattle Manure And Compost, John E. Gilley, Bahman Eghball Jul 1998

Runoff And Erosion Following Field Application Of Beef Cattle Manure And Compost, John E. Gilley, Bahman Eghball

Biological Systems Engineering: Papers and Publications

Manure or compost from beef cattle feedlots can be excellent sources of nutrients and organic matter when added to soils. This study was conducted to determine the effect of a single application of manure and compost on runoff and erosion under no-till and tillage conditions. Tillage consisted of a single disking operation up and down the slope on a Sharpsburg soil which was cropped to grain sorghum or wheat the previous season. Manure and compost were applied at rates required to meet corn fertility requirements. Additional experimental treatments included the application of inorganic fertilizer and an untreated check. The addition …

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Biodiesel Fuel From Animal Fat. Ancillary Studies On Transesterification Of Beef Tallow, Fangrui Ma, L. Davis Clements, Milford Hanna Jan 1998

Biodiesel Fuel From Animal Fat. Ancillary Studies On Transesterification Of Beef Tallow, Fangrui Ma, L. Davis Clements, Milford Hanna

Nebraska Center for Biotechnology: Faculty and Staff Publications

Transesterification of beef tallow was investigated. The solubility of ethanol in beef tallow was much higher than that of methanol. At 100 °C the solubility of methanol was 19% (w/w). The solubility of ethanol in beef tallow reached 100% (w/w) at about 68 °C. For the distribution of methanol between beef tallow methyl esters (BTME) and glycerol, the percentage of total methanol in the glycerol phase was higher than that in the fatty acid methyl ester (FAME) phase in a simulated system at room temperature. At 65-80 °C, however, the percentage of total methanol in FAME (60% (w/w)) was higher …

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Production Of Ethers Of Glycerol From Crude Glycerol - The By-Product Of Biodlesel Production, Hossein Noureddini, W R. Dailey, B A. Hunt Jan 1998

Production Of Ethers Of Glycerol From Crude Glycerol - The By-Product Of Biodlesel Production, Hossein Noureddini, W R. Dailey, B A. Hunt

Papers in Biomaterials

Methyl esters of fatty acids (also known as biodiesel), made from the transesterification of vegetable oils and animal fats with methanol, have shown a lot of promise as alternative diesel fuels. Glycerol is the inevitable byproduct of the trans-esterification process. While there are existing markets for glycerol, a significant increase in availability of glycerol, re-sulting from the expanded use of vegetable oils and animal fats, would destabilize the glycerol market. Direct addition of glycerol to the fuel is not possible, however, derivatives of glycerol such as ethers have potential for use as additives with biodiesel, diesel or biodiesel-diesel blends. In …

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Design Of Tapered Augers For Uniform Unloading Particulate Material From Rectangular Cross-Section Containers, M. S. Burr, Michael F. Kocher, David D. Jones Jan 1998

Design Of Tapered Augers For Uniform Unloading Particulate Material From Rectangular Cross-Section Containers, M. S. Burr, Michael F. Kocher, David D. Jones

Biological Systems Engineering: Papers and Publications

The design equation for an auger to provide uniform unloading of particulate material from a container with a rectangular cross-section (Jones and Kocher, 1995) was revised to account for the minimum flighting height that could effectively unload particles with a known average smallest diameter. A minimum flighting height that was about 64% of the average smallest diameter of the particles was experimentally determined to obtain mean slopes of the top surface of the material not significantly different from zero for screened soybeans. A linear taper that best fit the square root curve for the inside diameter of the auger was …

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Relationships Among Grain Sorghum Quality Factors, Roberto A. Buffo, Curtis L. Weller, Anne M. Parkhurst Jan 1998

Relationships Among Grain Sorghum Quality Factors, Roberto A. Buffo, Curtis L. Weller, Anne M. Parkhurst

Biological Systems Engineering: Papers and Publications

Correlations among grain sorghum quality factors (proximate composition, physical properties, and water absorption properties) were evaluated. Samples of 46 commercial hybrids (24 and 22 from crop years 1993 and 1994) were analyzed for starch, protein, crude free fat, test weight, absolute density, 1,000 kernel weight, percent kernel abraded, water absorption index, initial water absorption rate, and moisture saturation point. Test weight, absolute density, and percent kernel abraded were positively correlated among themselves (r > 0.5). Protein was negatively correlated with both test weight and absolute density (r < -0.5), while moisture saturation point showed negative correlations with test weight, absolute density, 1,000 kernel weight, and percent kernel abraded (r < -0.4). Principal component factor analysis through the covariance matrix explained 95% of the total variation of quality factors among hybrids (two factors), and, through the correlation matrix, 85% of the total variation (five factors). Water absorption rate decreased with increasing starch content of grain sorghum kernels as water absorption rate increased and amount of water for saturation decreased with softening of kernels.

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Opto-Electronic Sensor System For Rapid Evaluation Of Planter Seed Spacing Uniformity, Michael F. Kocher, Yubin Lan, Changhe Chen, John A. Smith Jan 1998

Opto-Electronic Sensor System For Rapid Evaluation Of Planter Seed Spacing Uniformity, Michael F. Kocher, Yubin Lan, Changhe Chen, John A. Smith

Biological Systems Engineering: Papers and Publications

An opto-electronic seed spacing evaluation system that measured time intervals between seeds and detected front-to-back location of seed drop events relative to the planter was used to rapidly determine planter seed spacing uniformity in the laboratory. The seed detection sensor for the opto-electronic system consisted of a rectangular photogate with 24 phototransistors receiving light beams from 24 LEDs opposite to them. The system also included circuitry to interface the photogate with a digital I/O board in a personal computer. The opto-electronic system was tested with three planter configurations. During the tests, the photogate was positioned beneath the seed drop tube …

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