Characterization of soil organic matter under varying conservation management practices

Title from PDF of title page (University of Missouri--Columbia, viewed on May 15, 2013).The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file.Dissertation advisors: Drs. Keith W. Goyne and Peter P. MotavalliIncludes bibliographical references.Vita.Ph. D. University of Missouri--Columbia 2012."May 2012."This study examined the effects of three conservation management practices (i.e., no-till, grass vegetative filter strips (VFS) and agroforestry VFS) and four landscape positions (i.e., summit, shoulder, backslope and footslope) on many aspects of soil organic matter (SOM) quantity and quality. Initial work indicated that losses of dissolved organic carbon in runoff and stocks of soil organic carbon were not significantly different among conservation management practices 10 years after installation; therefore more sensitive indicators of SOM quality were required to detect changes in SOM at this spatial and temporal scale. Using multiple physical, chemical and biological indicators, this study demonstrated that VFS enhance aggregate-associated organic carbon in the particulate, adsorbed and occluded fraction, water-extractable organic carbon, labile KMnO4-oxidizable organic carbon, aggregate stability and microbial enzyme activity. Spectroscopic analysis of confirmed the greater proportions of partially degraded plant residues and a lower index of degradation under grass VFS. This may be the result of differing quantity and/or quality of organic matter inputs to the soil, or the result of differences in the decomposition rate due to protection in soil aggregates under the perennial vegetation of VFS. Overall, this study contributes to a greater understanding of conservation management practices on a field scale, and has implications for the role of management practices in the global soil carbon cycle.Includes bibliographical reference

Optical properties of metal nanoparticles investigated using polarised light.

The number of applications of metal nanoparticles (MNPs) are growing, and one of their most interesting properties is the interactions between MNPs and light. Especially in the visible regime, MNPs are very good at absorbing light at specific wavelengths, which opens interesting opportunities for use in many technological branches ranging from quantum dot displays to solar energy conversion. The principle behind the light absorption is the localised surface plasmon (LSPR) effect, in which the oscillating electric field of the light wave excites the electrons of the particle. The resonance of these oscillations is dependent on the size, shape, metal type and surrounding medium of the particle, and as such these parameters can be tailored depending on the application. Because of the surrounding mediums effect on the resonance wavelength, nanoparticles can be used in sensors to detect changes in refractive index. The goal of this thesis work is to investigate the viability of nanoparticle arrays as sensor devices, and more specifically explore a phenomenon in which the LSPR is selectively supressed to decrease the width of the plasmon peak, enhancing the sensitivity of potential sensor applications. Large arrays (1 x 1 mm) of gold nanoparticles with varying interparticle distances were fabricated using electron beam lithography (EBL), and the fabrication process was iteratively improved due to an initial lack of particle adhesion to the substrate surface, resulting in samples with a quality high enough to perform optical measurements. The particles were analysed by means of transmission spectroscopy, employing both polarised and unpolarised light, the former using a novel spectrometer. The measurements presented here are the first measurements carried out with polarised light at the UiB nanostructures laboratory. The results demonstrate the suppression of the LSPR, and the spectral positions of these suppression dips, as well as the relationship between the optical response of the particles when subjected to polarised light as compared to unpolarised light. This lays the foundation for further investigation into a refractive index sensor based on nanoparticles.Masteroppgave i nanovitenskapMAMN-NANONANO39

Disinfection by-product precursors and formation potentials of Missouri reservoirs

The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file.Title from title screen of research.pdf file (viewed on August 29, 2007)Includes bibliographical references.Thesis (M.S.) University of Missouri-Columbia 2006.Dissertations, Academic -- University of Missouri--Columbia -- Fisheries and wildlife.Dissolved organic carbon (DOC) in surface water affects the formation of halogenated disinfection by-products (DBP) in drinking water. Both the quality and quantity of DOC impact DBP formation. Allochthonous DOC is more reactive with chlorine than autochthonous DOC and our goal was to determine the relative influence of allochthonous and autochthonous inputs on the DBP precursor pool in Missouri. Samples were collected from 76 reservoirs spanning a 12 month period from January 2004 through December 2004 and regression models were developed for DBP surrogates. DOC, hydraulic flushing rate and total phosphorus were the best explanatory variables. Additionally, plots of stream discharge coincided well with UV₂₅₄ absorbance peaks. Chlorophyll was only weakly correlated with the DBP surrogates. These results indicate that watershed hydrology controlled the DBP precursor pool in Missouri reservoirs in 2004 and that hydraulic flushing rate may have more predictive value than chlorophyll when modeling DBP formation

Antibiotics and other additives for swine

Some material in this guide is adapted from Pork Industry Factsheet (PIH-31).John C. Rea and Trygve L. Veum (Animal Husbandry Department, College of Agriculture)Revised 7/80/5

Vitamin requirements of swine (1990)

Vitamins are essential nutrients for swine. The trend toward complete confinement swine production, however, has focused more attention on the need to supplement practical rations with adequate dietary sources of vitamins. This Guide will help swine producers overcome vitamin deficiencies in rations. It is a summary of important aspects of vitamin requirements of swine, with emphasis on meeting the needs of hogs fed practical swine rations in Missouri.Revised 5/90/5M

Relationships between the chemically determined body components of domestic animals

Cover title.Includes bibliographical references (pages 7-8)

Feeding the sow and gilt

"Gilts selected for breeding should be kept from getting fat. You can usually leave meat-type gilts on a high-energy finishing ration until they weigh 175 ti 209 pounds. Then select replacement gilts, remove them from the finishing herd and feed a restricted amount of growing ration."--First page.John C. Rea and Trygve L. Veum (Department of Animal Science, College of Agriculture)Revised 3/87/6

Evaluating additives for swine rations

"Swine producers today are making decisions about feed additives, which are promoted as an aid in reducing feed required per pound of gain. Additives on the market have been selected from a large number investigated for use in treatment of swine disease or as growth promoters."--First page.John C. Rea and Trygve L. Veum (Department of Animal Science, College of Agriculture)Revised 9/87/6

Mineral needs for swine rations

"Swine producers have known for years that minerals must be supplied in swine rations for optimum performance. Increased confinement raising of hogs has stimulated more interest in defining and meeting mineral needs of hogs."--First page.John C. Rea and Trygve L. Veum (Department of Animal Science, College of Agriculture)Revised 5/85/6

Vitamin E and selenium in swine rations

"2/88/5M""In recent years concern has increased for shortages of vitamin E or selenium in practical swine operations in Missouri or the Midwest. Problems which have occurred on some hog farms for these two nutrients have resulted in a change in recommendations."--First page.John C. Rea and Trygve L. Veum (Department of Animal Sciences, College of Agriculture