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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Microbiological Analysis of Residuals and Process Wastewater from Human and Animal Wastes: An Internship with the United States Environmental Protection Agency in Cincinnati, Ohio

Hayes, Gina L. 15 November 2006 (has links)
No description available.
22

Predication of Ammonia Emission From Poultry Layer and Dariy Houses Using an Alternative Mass Balance Method

Wang, Shunli 27 September 2010 (has links)
No description available.
23

The diet and management of domestic sheep and goats at Neolithic Makriyalos.

Mainland, Ingrid L., Halstead, P. 21 October 2009 (has links)
No / Until recently, osteological studies into ancient diet and health have primarily focused upon human remains. As a result, these areas of research are still in their infancy in the field zoo-archaeology. Animals have paid a heavy price for many major human advances, such as those in agriculture and transport. This use (and often abuse) of animals has left many tell-tale signs in their teeth and bones. Along with the many advantages in animal exploitation have also come major problems for humans. Thus, infectious diseases passed from animals to humans must have long played a significant evolutionary role in the development of society. The zooarchaeological record could provide an extremely important temporal framework for exploring and understanding past and current issues of human health and animal welfare. This volume provides one of the first contributions to the field, and may stimulate many more.
24

REGULATION OF CONCENTRATED ANIMAL FEEDING OPERATIONS: AN APPLICATION OF ECONOMIC THEORY TO FIRM DECISION MAKING AND APPLICATIONS FOR PUBLIC POLICY

Gramig, Benjamin 01 January 2004 (has links)
The livestock industry in the United States has experienced significant concentration and vertical integration in recent years. This change has resulted in greater observed levels of pollution attributed to concentrated animal feeding operations (CAFO) and society has attempted to use regulation to remedy these problems. Despite regulation at the federal and local level no documented improvement in water quality has been observed to date. This thesis is concerned with the response of profit-maximizing economic agents to the form of environmental regulation adopted at the federal level. A theoretical model of firm profit is proposed and analyzed using comparative statics to derive a variety of firm and policy relevant results. A qualitative discussion of monitoring and enforcement aspects of regulation and transaction costs in public policy implementation is provided. Results suggest that the form that regulation has taken fails to address the economic decision making process of the firm and thus fails to create incentives for more environmentally benign behavior.
25

Proteinabbau einheimischer Futtermittel im Pansen

Alert, Hans-Joachim 24 July 2013 (has links) (PDF)
Mit Hilfe der Pansen-Beutel-Methode wurde an drei trockenstehenden Kühen der intraruminale Rohproteinabbau von Futtermitteln ermittelt. Daraus wurden folgende UDP-Gehalte (k = 5 %/h) abgeleitet: Sojaextraktionsschrot: 30 %, Rapsextraktionsschrot: 33 %, Rapskuchen: 15 %, Roggenpressschlempe: 43 %, Weizen/Gerste-Trockenschlempe: 25 %, Ackerbohnen: 22-26 %, Körnerfuttererbsen: 20-24 %, Blaue Lupinen: 27-35 %, Leguminosen-Gras-Gemenge: 18-35 %. Bei Körnermaisschrot (trocken bzw. feucht konserviert) wurde der intraruminale Stärkeabbau bestimmt: trocken 42 % Abbau, feucht 18 % Abbau. Außerdem wurde an vier hochleistenden Kühen die Wirkung von Einzelfuttermitteln im Rahmen von Mischrationen auf die Pansenfermentation untersucht (pH-Wert, NH 3 -Gehalt, Gehalt an FFS im Pansensaft). Trotz des höheren intraruminalen Stärkeabbaus führte Feuchtkornmais zu keinem erhöhten Acidoserisiko (etwa gleicher Pansen-pH-Wert-Verlauf wie bei Trockenmais). Anhand der NH 3 -Gehalte im Pansensaft wurde ein verringerter Rohproteinabbau bei Einsatz des pansengeschützten Sojaextraxtionsschrots Soypass 50 nachgewiesen. Durch mikronisierte Rapssaat in der TMR konnte der Rohfettgehalt in der Rationstrockenmasse auf > 6 % erhöht werden, ohne dass die Pansenfermentation nachteilig beeinflusst wurde. Die Broschüre fasst alle Untersuchungsergebnisse zusammen.
26

Design and performance of an ammonia measurement system

Boriack, Cale Nolan 25 April 2007 (has links)
Ammonia emissions from animal feeding operations (AFOs) have recently come under increased scrutiny. The US Environmental Protection Agency (EPA) has come under increased pressure from special interest groups to regulate ammonia. Regulation of ammonia is very difficult because every facility has different manure management practices. Different management practices lead to different emissions for every facility. Researchers have been tasked by industry to find best management practices to reduce emissions. The task cannot be completed without equipment that can efficiently and accurately compare emissions. To complete this task, a measurement system was developed and performance tested to measure ammonia. Performance tests included uncertainty analysis, system response, and adsorption kinetics. A measurement system was designed for measurement of gaseous emissions from ground level area sources (GLAS) in order to sample multiple receptors with a single sensor. This multiplexer may be used in both local and remote measurement systems to increase the sampling rate of gaseous emissions. The increased data collection capacity with the multiplexer allows for nearly three times as many samples to be taken in the same amount of time while using the same protocol for sampling. System response analysis was performed on an ammonia analyzer, a hydrogen sulfide analyzer, and tubing used with flux chamber measurement. System responses were measured and evaluated using transfer functions. The system responses for the analyzers were found to be first order with delay in auto mode. The tubing response was found to be a first order response with delay. Uncertainty analysis was performed on an ammonia sampling and analyzing system. The system included an analyzer, mass flow controllers, calibration gases, and analog outputs. The standard uncertainty was found to be 443 ppb when measuring a 16 ppm ammonia stream with a 20 ppm span. A laboratory study dealing with the adsorption kinetics of ammonia on a flux chamber was performed to determine if adsorption onto the chamber walls was significant. The study found that the adsorption would not significantly change the concentration of the output flow 30 minutes after a clean chamber was exposed to ammonia concentrations for concentrations above 2.5 ppm.
27

Mesquite pod utilization for livestock feed: An economic development alternative in central Mexico

Silbert, Michele Sue, 1960- January 1988 (has links)
In central Mexico's semi-arid highlands, mesquite (Prosopis spp.) pods are utilized for food and livestock feed. In 1975, a union of 53 rural communities opened a storage and processing facility for mesquite pods. A study of the operation and the regional collection, sales, and use of mesquite was conducted to evaluate the industry's potential. Twenty-six communities were visited, and formal interviews were held with 35 subsistence farmers, 12 mesquite feed dealers, eight large-scale ranchers, and members of the mesquite union. The effect of climatic factors on mesquite pod harvests was analyzed. The study examined opportunity costs for land and labor and the costs and returns of improvements to the operation. The mesquite facility has increased income production for rural farmers and provided a local source of nutritious livestock feed. Potential improvements to the industry include pest control, production of mixed feeds, improved management, and marketing. Similar operations could succeed in areas with dense mesquite woodlands, a history of pod collection and use, and a need for seasonal income production.
28

Spurenelementversorgung bei Milchrindern

Steinhöfel, Olaf, Fröhlich, Brigitte, Zentek, Jürgen, Kriesten, Anett, Männer, Klaus 02 October 2013 (has links) (PDF)
In den Mischfutterrationen für Milchrinder wurde ein mittlerer Gehalt von Kupfer, Zink, Mangan und Selen ermittelt, der 2,5-fach über der Versorgungsempfehlung liegt. Neben den umweltrelevanten Konflikten dieser Praxis sind auch Versorgungsprobleme bei den Milchrindern aufgrund unerwünschter Interaktionen der Elemente nicht auszuschließen. In elf sächsischen Milchviehbetrieben wurden die Ursachen der Überversorgung untersucht und Vorschläge zur Optimierung der Spurenelementversorgung von Milchrindern erarbeitet. Dabei konnte die mittlere Kupfer-, Zink- und Selenkonzentration in den TMR um im Mittel 25 %, d. h. auf ein mittleres Versorgungsniveau der Tiere von 150 % der Versorgungsempfehlung reduziert werden. Das Heft fasst die Ergebnisse der Untersuchungen zusammen.
29

Emissions From Concentrated Animal Feeding Operations During Wet and Dry Periods in the Southeastern United States

Winchester, Jesse N. F. 01 May 2015 (has links)
Air quality modeling is a recent development in atmospheric science dedicated to simulating the characteristics of surface emissions within the context of a variety of meteorological conditions. In western Kentucky, there are several concentrated animal feeding operations (CAFOs) that emit a variety of gases, including sulfur dioxide (SO2). The hypothesis was that the concentration and spread of SO2 emissions from these sources would differ between wet and dry periods over the CAFO locations. In this thesis, point emissions from locations representing CAFOs in western Kentucky and the transit of SO2throughout the southeastern U.S. were simulated in multiple sensitivity experiments using the Weather Research and Forecasting model with Chemistry (WRFChem). Simulations were performed for the convective precipitation events that occurred over western Kentucky between July 7 and July 13, 2012. The spatial coverage of SO2 emissions originating from the locations was reduced during precipitation events and expanded during dry periods. The average concentration of SO2 over the study area was also higher during the breaks between precipitation events than during times when precipitation was occurring. The highest concentrations of SO2 exceeding 1,000 pptv remained within close range of the emission locations for the majority of the simulations, except for when local surface winds were blowing at higher speeds. Most emissions from the locations remained limited to the surface and 850 mb levels.
30

Precipitation of Phosphate Minerals from Effluent of Anaerobically Digested Swine Manure

Lin, Alex Y. 01 January 2012 (has links)
Swine production represents approximately 40% of the world's meat production, and its wastes contain high concentrations of organic carbon, nitrogen (N), and phosphorus (P). Anaerobic digestion is an increasingly popular technology for treating animal wastes while simultaneously generating energy. Its propagation and ability to solubilize organic N and P make adding a struvite recovery process attractive. Recovering struvite (MgNH4PO4) from anaerobically digested swine waste can address global P shortages, meet P discharge guidelines, and produce slow-release fertilizer, which can be sold for revenue. Anaerobic digesters were operated with at organic loading rates of 3.4-3.9 g volatile solids per liter per day to provide consistent effluent for struvite precipitation studies. Three research questions about struvite precipitation were addressed in this study, specifically what is the (1) required Mg:PO4 ratio, (2) effect of organic matter, and (3) effect of storage time and conditions on struvite precipitation from effluent of anaerobically digested swine manure? Mg:PO4 ratios between 1.3-1.8 were determined to be the economic optimum and precipitated 81-90% of P from synthetic wastewater with calcium phosphate minerals dominating. Under P-limited conditions, a chemical equilibrium model (Visual MINTEQ v.3.0) predicted over 99% P removal with a precipitate mixture of struvite, calcium phosphates, and magnesite. Synthetic wastewater experiments without organic matter removed approximately 85% P with a precipitate mixture of struvite, dolomite, calcite, brucite, and calcium phosphates. Real swine effluent removed more than 95% of P and had a similar mixture of precipitates as synthetic wastewater, but in different concentrations. Organic acids were suspected to prevent struvite formation. Stored anaerobically digested swine wastewater under varying conditions all suggest calcium phosphates form naturally over time. Precipitation of struvite is best carried out as soon as possible to increase the purity of struvite. Although struvite recovery was possible, the conditions for struvite precipitation must be controlled carefully to obtain highly pure struvite.

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