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Full-Text Articles in Life Sciences

Generation And Calibration Of Standard Gas Mixtures For Volatile Fatty Acids Using Permeation Tubes And Solid Phase Microextraction, Jacek A. Koziel, Jarett P. Spinhirne Oct 2003

Generation And Calibration Of Standard Gas Mixtures For Volatile Fatty Acids Using Permeation Tubes And Solid Phase Microextraction, Jacek A. Koziel, Jarett P. Spinhirne

Jacek A. Koziel

Volatile fatty acids (VFAs) are major components of odors associated with agricultural operations and livestock housing, solid waste processing and disposal, and industrial and municipal wastewater collection and treatment systems. Emissions estimation and assessment of odor control methods depend on reliable air sampling and analysis methods for VFAs. The objective of this research was to develop and test a method for continuous and reliable generation of standard gas mixtures for VFAs based on permeation tubes. Standard gas mixtures for acetic, propionic, isobutyric, butyric, isovaleric, valeric, and hexanoic acids were generated with permeation tubes and monitored for a 100-day period. The ...


Estimations Of Ammonia And Hydrogen Sulfide Fluxes From Cattle Feedlot Surfaces In Texas High Plains, Bok-Haeng Baek, Jacek A. Koziel, Jarett P. Spinhirne, David B. Parker, Nolan A. Cole Oct 2003

Estimations Of Ammonia And Hydrogen Sulfide Fluxes From Cattle Feedlot Surfaces In Texas High Plains, Bok-Haeng Baek, Jacek A. Koziel, Jarett P. Spinhirne, David B. Parker, Nolan A. Cole

Jacek A. Koziel

A dynamic flow-through chamber system and continuous analyzers were used for on-site measurements of ammonia-nitrogen (NH 3 -N) and hydrogen sulfide-sulfur (H 2 S-S) fluxes from commercial feedlot surfaces in northwestern Texas during two week period in the summer of 2002. Ambient air and air inside chamber temperatures, and manure pack temperature were measured continuously. Manure pack moisture content, pH, and TKN were measured daily to characterize its correlation with NH 3 -N fluxes. The preliminary average NH 3 -N flux from the feedlot surface for the entire measurement period was 1,669 ± 1,212 NH 3 -N µ g ...


Ammonia Concentrations In Poultry Broiler Production Units Treated With Liquid Alum, K. A. Armstrong, Robert T. Burns, F. R. Walker, L. R. Wilhelm, D. Raj Raman Oct 2003

Ammonia Concentrations In Poultry Broiler Production Units Treated With Liquid Alum, K. A. Armstrong, Robert T. Burns, F. R. Walker, L. R. Wilhelm, D. Raj Raman

D. Raj Raman

High ammonia concentrations in commercial broiler production houses can result in poor bird performance, lower feed conversion ratios, and higher mortalities. Growers have traditionally controlled in-house ammonia levels by increasing ventilation. During cold weather, increased ventilation rates result in higher heating energy requirements. Granular alum (aluminum sulfate, Al2(SO4)3 · 14H2O) has been successfully used as a litter amendment to reduce ammonia volatilization from litter inside broiler production houses. In this study, liquid aluminum sulfate was investigated as a litter amendment for ammonia suppression in four commercial poultry-broiler units. This project investigates four treatment levels of liquid alum in four ...


Release And Transport Of Bacteria And Nutrients From Livestock Manure Applied To Pastureland, Michelle L. Soupir Jul 2003

Release And Transport Of Bacteria And Nutrients From Livestock Manure Applied To Pastureland, Michelle L. Soupir

Michelle L. Soupir

Transport of fecal bacteria and nutrients from point and nonpoint sources to surface water bodies is of significant concern in Virginia and the United States. In Virginia, 4,320 river miles are impaired for one or more beneficial use and 72% of the streams are impaired due to pathogen indicators (VDEQ, 2002). Land applications of manure from confined animal systems and by direct deposit by grazing animals are both major sources of fecal bacteria and nutrients in runoff. Therefore, an understanding of the overland transport mechanisms for fecal bacteria and nutrients is very important for the development of best management ...


Assessment Of Moisture Control And Additives For Odor Reduction From Open-Lot Feedyard Surfaces, Jocelyn D. Buchanan, David B. Parker, Marty B. Rhoades, Jacek A. Koziel, William J. Rogers Jul 2003

Assessment Of Moisture Control And Additives For Odor Reduction From Open-Lot Feedyard Surfaces, Jocelyn D. Buchanan, David B. Parker, Marty B. Rhoades, Jacek A. Koziel, William J. Rogers

Jacek A. Koziel

Amendments for reducing odor from open-lot beef cattle feedyards were evaluated in the laboratory. Manure was placed in small Tupperware® containers. Water and amendments were added to the manure surface and the containers were attached to a vacuum pump that continually passed 2.5 L/min of carbon-filtered air over the surface. Eleven different amendments were tested, at two different concentrations, in a series of five experiments. Odor samples were collected 3 times during a 10-day period in each experiment and were analyzed by trained panelists for detection threshold (DT), intensity and hedonic tone. None of the amendments showed any ...


Development Of A Controller Area Network Based Handheld Data Acquisition System For Identity Preservation, Matthew J. Darr, Jason Kellam Ward, Timothy S. Stombaugh, Michael D. Montross Jul 2003

Development Of A Controller Area Network Based Handheld Data Acquisition System For Identity Preservation, Matthew J. Darr, Jason Kellam Ward, Timothy S. Stombaugh, Michael D. Montross

Matthew J. Darr

The development of a diverse, modular and portable system to accurately measure and record field operations is required to effectively bring identity preservation of crops to all farms and farmers. A demonstration system has been built based on a worldwide standard communications protocol and was evaluated for its ability to efficiently measure a variety of field operations and management practices. The CAN Bus 2.0B communication protocol was used to record GPS location data, ground speed and simulated spraying system data. This data was compiled and stored in a form that was compatible with multiple software programs for the purposes ...


Soil Moisture Estimation From Remotely Sensed Hyperspectral Data, Amy L. Kaleita, Lei F. Tian, Haibo Yao Jul 2003

Soil Moisture Estimation From Remotely Sensed Hyperspectral Data, Amy L. Kaleita, Lei F. Tian, Haibo Yao

Amy L. Kaleita

A methodology for mapping surface soil moisture content across an agricultural field from optical remote sensing and ground sampling is developed. This study uses both ground-based and remotely sensed spectral measurements of soil reflectance in visible and near-infrared wavelengths and concurrent measurements of volumetric soil moisture within the top 6 cm. After determining appropriate wavelengths for soil moisture estimation from spectral reflectance, a cokriging scheme was used to generate soil moisture maps. Results indicate that combining reflectance and ground measurements can yield more detailed maps of soil moisture than ground measurement alone.


Properties Of Corn Masa Processing Byproducts, Kurt A. Rosentrater Jul 2003

Properties Of Corn Masa Processing Byproducts, Kurt A. Rosentrater

Kurt A. Rosentrater

The production of corn masa-based products in the U.S. has been increasing over the last several years, and as a result, so has the quantity of waste materials generated from this industry. These byproduct materials may have potential for value-added processing and utilization, which are options that hold the promise of economic benefits for masa processors and decreased potential pollution for the environment. Fundamental to any byproduct development, however, is a full characterization of the processing residue, because physical and nutritional properties are necessary for the proper design of processing operations and applications. Vital physical properties include moisture content ...


Characterization Of Volatile Organic Compounds In Bovine Breath Using Solid-Phase Microextraction And Gas Chromatography-Mass Spectrometry, Jacek A. Koziel, Jarett P. Spinhirne, Norbert K. Chirase Jul 2003

Characterization Of Volatile Organic Compounds In Bovine Breath Using Solid-Phase Microextraction And Gas Chromatography-Mass Spectrometry, Jacek A. Koziel, Jarett P. Spinhirne, Norbert K. Chirase

Jacek A. Koziel

A face mask sampling device, DVB/Carboxen/PDMS 50/30 µ m solid phase microextraction (SPME) fibers, and a gas chromatograph with a mass spectrometer detector (GC-MS) were used for sampling and analysis of volatile organic compounds (VOCs) in bovine breath. Breath of 3 morbid steers with respiratory tract infections and 3 healthy steers were sampled 7 times in 19 days for 15 min at each sampling. A total of 21 VOCs were detected, many of them for the first time in cattle breath. Preliminary statistical analyses using Chi-square Test on the frequency of detection of each VOC in each ...


Odor Characterization At Open-Lot Beef Cattle Feedyards Using Triangular Forced Choice Olfactometry, David B. Parker, Marty B. Rhoades, Brent W. Auvermann, Jacek A. Koziel Jul 2003

Odor Characterization At Open-Lot Beef Cattle Feedyards Using Triangular Forced Choice Olfactometry, David B. Parker, Marty B. Rhoades, Brent W. Auvermann, Jacek A. Koziel

Jacek A. Koziel

Odor samples were collected two to four times per month over a one-year period in 2002-2003 at three large open-lot beef cattle feedyards in the Texas panhandle. Samples were collected in 10 L Tedlar bags using a vacuum chamber upwind of the feedyard, downwind of the pens, and downwind of the runoff storage pond. Samples were analyzed in the odor lab for detection threshold (DT) using triangular forced choice olfactometry with trained human odor panelists. Full-strength odor samples were also analyzed for intensity and hedonic tone. Weather data was collected on-site at each of the feedyards for correlation to odor ...


Using Efficient Software Architecture For Computer-Based Training Programs To Promote International Development, Kurt A. Rosentrater, Kari Pape Rosentrater Jul 2003

Using Efficient Software Architecture For Computer-Based Training Programs To Promote International Development, Kurt A. Rosentrater, Kari Pape Rosentrater

Kurt A. Rosentrater

Many international agencies offer volunteer services to improve agricultural knowledge and infrastructure in developing countries. Although effective, these efforts are severely constrained by limited funding and personnel, and can only address a fraction of current global educational needs. Computer-based training programs, either in the form of CD-ROM-based or Internet-based incarnations, hold the promise of removing many of the obstacles that currently confront international volunteer efforts. The art of web programming has drastically accelerated in recent years, both in terms of capacity as well as complexity. One reason for this is that advanced software has been developed to simplify and speed ...


Background Odors In Tedlar® Bags Used For Cafo Odor Sampling, David B. Parker, Marty B. Rhoades, Jacek A. Koziel, Jarett Spinhirne Jul 2003

Background Odors In Tedlar® Bags Used For Cafo Odor Sampling, David B. Parker, Marty B. Rhoades, Jacek A. Koziel, Jarett Spinhirne

Jacek A. Koziel

Tedlar® film is manufactured in a wet solvent process and continues to emit organic compounds after manufacturing. Tedlar® bags are used for odor sampling at concentrated animal feeding operations (CAFOs). Odor regulations for CAFOs vary widely, but maximum detection thresholds (DTs) of 2 to 15 have been proposed downwind of feeding operations. Results at the WTAMU Olfactometry Laboratory have shown that both commercially available Tedlar® bags and homemade Tedlar® bags have a detectable background odor (DTs of 20 to 60 typical) even following standard protocols for purging. Purging the bags before sampling was not effective in reducing DTs to acceptable ...


Estimation Of Ammonia And Hydrogen Sulfide Emissions From Cattle Feedlots In Texas, Bok-Haeng Baek, Jacek A. Koziel, Jarett P. Spinhirne, David B. Parker, Nolan A. Cole Jul 2003

Estimation Of Ammonia And Hydrogen Sulfide Emissions From Cattle Feedlots In Texas, Bok-Haeng Baek, Jacek A. Koziel, Jarett P. Spinhirne, David B. Parker, Nolan A. Cole

Jacek A. Koziel

A dynamic flow-through chamber system and continuous analyzers were used for on-site measurements of ammonia-nitrogen (NH 3 -N) and hydrogen sulfide-sulfur (H 2 S-S) fluxes from commercial feedlot surfaces in northwestern Texas during two week period in the summer of 2002. Manure pack moisture content, pH, and TKN were measured daily to characterize its relation with NH 3 -N fluxes. The preliminary average NH 3 -N and H 2 S-S flux from the feedlot surface were 1,669 ± 1,212 NH 3 -N µ g/m 2 /min and 1.884 ± 1.497 H 2 S-S µ g S/m ...


Soil Moisture Estimation From Remotely Sensed Hyperspectral Data, Amy L. Kaleita, Lei Tian, Haibo Yao Jul 2003

Soil Moisture Estimation From Remotely Sensed Hyperspectral Data, Amy L. Kaleita, Lei Tian, Haibo Yao

Amy L. Kaleita

A methodology for mapping surface soil moisture content across an agricultural field from optical remote sensing and ground sampling is developed. This study uses both ground-based and remotely sensed spectral measurements of soil reflectance in visible and near-infrared wavelengths and concurrent measurements of volumetric soil moisture within the top 6 cm. After determining appropriate wavelengths for soil moisture estimation from spectral reflectance, a cokriging scheme was used to generate soil moisture maps. Results indicate that combining reflectance and ground measurements can yield more detailed maps of soil moisture than ground measurement alone.


Modeling Of Sediment Trapping In A Vegetative Filter Accounting For Two-Dimensional Overland Flow, Matthew J. Helmers, Dean E. Eisenhauer, Thomas G. Franti, Michael G. Dosskey Jul 2003

Modeling Of Sediment Trapping In A Vegetative Filter Accounting For Two-Dimensional Overland Flow, Matthew J. Helmers, Dean E. Eisenhauer, Thomas G. Franti, Michael G. Dosskey

Matthew J. Helmers

Vegetative filters (VF) are used to remove sediment and other pollutants from overland flow. When modeling the hydrology of VF it is often assumed that overland flow is planar but our research indicates that it can be two-dimensional with converging and diverging pathways. Our hypothesis is that flow convergence will negatively influence the sediment trapping capability of VF. The objectives were to develop a two-dimensional modeling approach for estimating sediment trapping in VF and to investigate the impact of converging overland flow on sediment trapping by VF. In this study, the performance of a VF that has field-scale flow path ...


Generation And Calibration Of Standard Gas Mixtures For Volatile Fatty Acids Using Permeation Tubes And Solid-Phase Microextraction, Jacek A. Koziel, Jarett P. Spinhirne Jan 2003

Generation And Calibration Of Standard Gas Mixtures For Volatile Fatty Acids Using Permeation Tubes And Solid-Phase Microextraction, Jacek A. Koziel, Jarett P. Spinhirne

Jacek A. Koziel

Volatile fatty acids (VFAs) are major components of odors associated with agricultural operations and livestock housing, solid waste processing and disposal, industrial and municipal wastewater collection, and treatment systems. Emission estimation and assessment of odor control methods depend on reliable air sampling and analysis methods for VFAs. The objective of this research was to develop and test a method for continuous and reliable generation of standard gas mixtures for VFAs based on permeation tubes. Standard gas mixtures for acetic, propionic, isobutyric, butyric, isovaleric, valeric, and hexanoic acids were generated with permeation tubes and monitored for a 100-day period. The gravimetric ...


Characterizing Volatile Fatty Acids And Other Gases In A Rumen Closed In Vitro Fermentation System Using Solid Phase Microextraction, Jarett P. Spinhirne, Jacek A. Koziel, Norbert K. Chirase Jan 2003

Characterizing Volatile Fatty Acids And Other Gases In A Rumen Closed In Vitro Fermentation System Using Solid Phase Microextraction, Jarett P. Spinhirne, Jacek A. Koziel, Norbert K. Chirase

Jacek A. Koziel

A new method for rapid sampling and qualitative characterization of the headspace gases of closed in vitro cultures using solid phase microextraction (SPME) was evaluated for ruminal fluid and ruminal fluid with feed containing a feed additive. Gas sample collection was achieved by exposing a DVB/Carboxen/PDMS 50/30 .m SPME fiber to the headspace of cultures for 1 min every hour. This was followed by immediate analysis on a GC–MS and then reuse of the SPME fiber. Acetic, propionic, isobutyric, butyric, isovaleric, valeric, and hexanoic acids and toluene, dimethyl disulfide, and pentadecane were identified in the headspace ...