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39 Uppsatser om Nitrate - Sida 1 av 3

The effect of additional nitrate and sulfur in the diet on the methane production in cattle

A growing population together with a change in food habits to a more diverse diet containing more animal products such as meat and milk makes the possibility to produce and sell products of cattle a growing market. And at the same time there is an ongoing debate about global warming, where raising cattle is questioned due to their high production of enteric methane. To be able to raise animals in a more environmental friendly way and at the same time improve productivity in a developing country such as Vietnam would be favorable. The use of feed additives with high electron affinity could decrease the methane production and at the same time improve the gross energy digested. Nitrate and Sulfur are both good electron acceptors, but due to its toxic effects the use of Nitrate in feed has been neglected.

Nitrat i grundvattnet : Modellanalys av vattenflöde till Hörviks vattentäkt

A well, situated on Listerlandet in the western part of Blekinge in Sweden, has a very high content of Nitrate. Water with a too high content of Nitrate is hazardous to human health, in particular to small children. The area surrounding the well is mostly drained agricultural land with some larger farms for chicken and mink. The well takes its water from the bedrock and is deeper than most other wells affected by Nitrate. The bedrock in the area is dominated by limestone with a relatively high flow of water.This thesis was performed in order to find the source of the Nitrate.

Protesutveckling

This report investigates the possibility of developing a new and improved hip prosthesis. The result were five different materials that could be used for the prosthesis. These five solutions were Silicone Nitrate on Cobolt Chrome, phase stabilized Zirconium Oxide on Cobolt Chrome, Silicone Nitrate on Silicone Nitrate, DLC coated phase stabilized Zirconium Oxide and Chromium nitride coated Cobolt Chrome on Cobolt Chrome. In addition to this it was also investigated how to best market the prosthesis and how to transport them from production sites to hospitals..

Biologisk reducering av nitrat och nitrit i vatten

During the summer 2007 was a scrubber tested at Gruvön papper mill in Grums. The scrubber reduced NOx with 90 % in flue gas. NOx was transferred from the flue gas to a scrubber liquid as Nitrate and nitrite. The scrubber liquid needs to be purified from Nitrate and nitrite. One possible solution is to clean the scrubber liquid in Gruvön biologic cleaning construction.Microorganisms in the biologic cleaning construction need to assimilate nitrogen. There are environments free from oxygen in the cleaning construction.

Kan kväve bevaras i dräneringsvatten från åkermarksom lagras i dammar? : ett laboratorieförsök

The aim of this thesis was to examine if it is possible to keep nitrogen in the form of Nitrate(NO3-) in ponds from one season to another by keeping a high concentration of oxygen in thepond water. This hypothesis was tested by doing a lab experiment where two systems werecompared according to Nitrate concentration. One system had high concentration of oxygen inthe water and one had low concentration of oxygen. Before the main experiment wasconducted I did a pilot study to test the system setup and included parameters. The result fromthis study and the main study did not show the same result.

Kvävestatus och risk för nitrifikation i två avverkade skogsområden i Halland

Nitrogen deposition leads to environmental damage in areas where the nitrogen deposition is high. Southwest Sweden receives an annual nitrogen deposition of up to 20 kg N/ha. Nitrogen that is not assimilated by the vegetation is accumulated in the soil, which may lead to nitrogen saturation and an elevated risk of nitrogen leaching. Nitrogen leaching from forest areas in southern Sweden has proven to be higher than from agricultural areas, which have been thought to be the main contributors to elevated nitrogen levels in rivers and lakes. The amount of nitrogen that leaches depends on the fraction of the total nitrogen in the soil that consists of Nitrate, since Nitrate is easily transported through the soil.

Närsalter och bottenlevande organismer i Mönsteråsviken

The focus of this study was to examine the nutrients and benthic organisms of the bay ?Mönsteråsviken?, which is influenced by eutrophication. The purpose was also to look at an interesting gradient forming in the bay, namely the distance from the river outflow of Lillån. At 18 sampling sites in the bay samples of water, sediments and benthic organisms were collected in late April of 2011. The water was analyzed for Nitrate, phosphate and chlorophyll.

Nya tillämpningar för utandningstest kopplade till Kibions diagnostikinstrument IRIS ®

The focus of this study was to examine the nutrients and benthic organisms of the bay ?Mönsteråsviken?, which is influenced by eutrophication. The purpose was also to look at an interesting gradient forming in the bay, namely the distance from the river outflow of Lillån. At 18 sampling sites in the bay samples of water, sediments and benthic organisms were collected in late April of 2011. The water was analyzed for Nitrate, phosphate and chlorophyll.

Grundvattenskydd och markanvändning i tre olika länder- effekter för miljö och samhälle

AbstractDrinking water is an important resource on Earth both for humans and animals. Although most of the surface is covered by water only a small quantity is available as drinking water. Our manner of living creates a lot of pollution which has an environmental impact. Groundwater has a protracted turnover time in the soil and it can take many years before the effects of human impact are detected. The Swedish environmental object is ?Good groundwater quality? which aims to provide a safe and sustainable supply of drinking water today and in the future.

Bottensubstrat och dess inverkan på reducering av BOD5, COD och TKN i lakvatten genom konstruerade rotzonsanläggningar : En pilotstudie vid Univates, Lajeado ? RS Brasilien

Treatment wetlands been showed efficient for reducing pollutant in waste water. In Lajeado ? RS, Brazil the landfill has poor leachate water treatment. It is necessary to supplement the treatment plant because they need to reduce BOD, COD and Nitrate of the water going to recipient. A subsurface flow wetland (SSF) can be a good choice.  In order to be able to design an efficient SSF it is important to understand how the grain sizes of a substrate affect the reducing of pollutants in waste water.

Tillsats av biokol till en svensk sandjord : effekter på lustgasavgång, kväveretention och andel vattenfyllda porer

In a column experiment the effect of three different biochars on nitrous gas emissions, nitrogenretention and water filled pore space (WFPS) were studied in a Swedish sandy soil, classified as aCryopsamment. Ammonium retention was positively correlated, while KCl-extractable ammoniumwas negatively correlated, with the specific area of the biochars. The question was raised whether thenegative correlation between extractable ammonium and biochar specific area reflects the amount ofammonium present in the soil or its extractability from the biochar, and whether methods forextracting soil mineral nitrogen, like KCl-extractions, have to be modified for application on biocharamended soils. There was a tendency of increased Nitrate retention and KCl-extractable Nitrate withbiochar and KCl-extractable Nitrate was positively correlated with the specific area of the biochar. pHwas higher for all biochars compared with control, although the differences were not significant, andWFPS was lowered by biochar addition, significantly in one case.

Methane emission from nitrate-treated tannin rich feed for cattle in Vietnam

In developing countries such as Vietnam the population consumes more animal products for example milk and meat than before which requires greater livestock production. Ruminants contributes to more methane emission which creates a dilemma between food production and its environmental impact. By feeding ruminants with nutritive crops which humans can not assimilate the animal performance will increase in terms of better growth and milk production without inpinging on food that can be consumed directly by humans. Increasing animal performance reduces methane emission in terms of amount of methane in kg-1 milk and meat which today is much greater in developing countries than developed countries. The aim of the study was to investigate tropical tannin-rich legumes for their potential as a feed supplement for ruminants made in vitro.

Grundvattensänkning till följd av järnvägstunnel genom Hallandsås : miljökonsekvenser relaterade till förändrad kväveomsättning i mark

This thesis was carried out to give some background information to a report of SLU (Swedish University of Agricultural Sciences) for the Swedish National Rail Administration (Banverket). The requested information was to provide basic data for an environmental impact assessment of the construction of the tunnel through Hallandsås. The aim with the thesis work was to discuss and quantify the leaching of Nitrate and the emission of nitrous oxide from the soil at the groundwater level established through the tunnel project. The nitrogen related processes that could be affected were described and discussed. The different areas where a decreased groundwater level can cause changes in the nitrogen processes are the wet and moist areas.

Water balance and nitrate leaching from arable land in a changed climate : a model study

This thesis aims to present the essential background on how to perform climate changeimpact assessments, and to present the results from a climate impact assessment on waterbalance and Nitrate leaching for an arable Swedish soil. The soil is a sandy soil in southwesternSweden, grown with spring cereals. This study is meant to be a benchmark example,and cannot be seen as a regional or national assessment for Sweden, rather as an approachto present and analyze the most important parts of these kinds of assessments.A dynamical simulation model (COUP, Jansson and Karlberg, 2004) was used for thisstudy. The model was parameterized and calibrated against data from an experimental site,located in Mellby in Hallands county, south western Sweden. Measurements were carriedout between 1st of April 1988 and 1st of April 1991.

The effect of arginine on root system development in Norway spruce (Picea abies L. Karst) somatic embryos

The demands for higher production yields and better quality materials from the forests are increasing globally. Tree breeding programs are directed to meet the future demands on forests. In order to capture the full benefits from the breeding programs, clonal propagation is necessary. For most conifer species, somatic embryogenesis (SE) is the only available option for large scale clonal propagation of Elite clonal material. For Norway spruce (Picea abies L.

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