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Articles 31 - 35 of 35

Full-Text Articles in Biological Engineering

Mechanical And Barrier Properties Of Edible Corn And Wheat Protein Films, T. P. Aydt, Curtis Weller, R. F. Testin Jan 1991

Mechanical And Barrier Properties Of Edible Corn And Wheat Protein Films, T. P. Aydt, Curtis Weller, R. F. Testin

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Published methods for production of homogeneous edible films from com and wheat proteins were adapted. Barrier and mechanical properties of the edible films were evaluated with procedures commonly used on polymeric films. Mechanical property data included thickness, elongation, tensile strength, tear strength, and burst strength measurements. Barrier property data included water vapor, oxygen, and carbon dioxide gas transmission rate measurements. Homogeneous com and wheat protein films were found to have low tensile strengths, far less than cellophane. Com films were brittle while wheat films were elastic in comparison to cellophane. All three types of film had low permeabilities for dry …


A Cooperative Educational Program To Reduce Soil Erosion, David P. Shelton, Elbert C. Dickey, Paul J. Jasa, David A. Biere, Susan Smydra Krotz Jan 1991

A Cooperative Educational Program To Reduce Soil Erosion, David P. Shelton, Elbert C. Dickey, Paul J. Jasa, David A. Biere, Susan Smydra Krotz

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Eastern Nebraska, especially the northeastern portion, has a history of severe soil erosion, due in part to a predominance of steep slopes and highly erodible soils (12). While the average annual allowable soil loss ("T" value) for most of these soils is five tons per acre, some fields have annual soil erosion rates that exceed 100 tons per acre. The loss of topsoil is critical, of course, but erosion from cropland also results in the removal of fertilizers and pesticides, which degrades water quality.

Even though farmers are generally aware that soil erosion is a national problem, many …


Estimating Percent Residue Cover Using The Line-Transect Method, David P. Shelton, Elbert C. Dickey, Roger Kanable, Stewart W. Melvin, Charles A. Burr Jan 1991

Estimating Percent Residue Cover Using The Line-Transect Method, David P. Shelton, Elbert C. Dickey, Roger Kanable, Stewart W. Melvin, Charles A. Burr

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Estimating Percent Residue Cover Using the Line-Transect Method

The line-transect method is one of the easiest method to use in the field to determine the percent residue cover on the surface. Accurate measurement is necessary to determine if enough cover is present to comply with the conservation plan.

The following is a step-by-step procedure for using the line-transect method to measure the percentage of residue cover.

Step 1

Use a 100-foot or 50-foot measuring tape for measuring residue cover. Other measuring length or even knotted ropes can be used if the appropriate multiplication factor is used to calculate the percentage. …


Residue Management To Control Soil Erosion By Water, Elbert C. Dickey, David P. Shelton, Paul J. Jasa, Michael C. Hirschi Jan 1991

Residue Management To Control Soil Erosion By Water, Elbert C. Dickey, David P. Shelton, Paul J. Jasa, Michael C. Hirschi

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The Erosion Process

Erosion of topsoil begins when water detaches individual soil particles from clod and other soil aggregates. A single raindrop may seem insignificant, yet collectively, raindrops strike the ground with surprising force. During an intense storm, rainfall can loosen and detach up to 100 tons of soil per acre and can be especially erosive when residue mulch or vegetation are not present to absorb their impact.

Two problems often occur during rainstorms. The rate of rainfall can exceed the rate at which water can enter the soil and raindrop impact forces can partially seal the soil surface. In …


Equipment For Ridge Planting, Elbert C. Dickey, Paul J. Jasa Jan 1991

Equipment For Ridge Planting, Elbert C. Dickey, Paul J. Jasa

Department of Agricultural and Biological Systems Engineering: Faculty Publications

In ridge plant systems, crops are planted into ridges formed during cultivation of the previous crop.

Row cleaning devices on the planter push weed seed and residue lying on the soil surface from the ridge to the area between the rows, or row middles. The crop seed is planted into the old row in a cleanly tilled strip at a higher elevation than the row middles. A band application of herbicide behind the planter typically is used in the row for weed control. Crop cultivation controls weeds between the row and rebuilds ridges for the following year.

Ridge plant systems …