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71 Uppsatser om Anaerobic - Sida 4 av 5

Kväveomsättning i gräsmark med olika artantal och artsammansättningar :

This study was carried out at the Swedish University of Agricultural Sciences, Dept. of Agricultural Research for Northern Sweden. The aim of the study was to determine how plant species richness and diversity influence the nitrogen pools and nitrogen fluxes in the soil. Plant and soil samples from a biodiversity experiment in grasslands were used. Thirty plots with 12 grassland plant species (legumes, grasses, and non-legume herbs), combined from 1-12 species were investigated.

Validation of Steins/Arla Foods method for lactate fermenting clostridia in milk

One of the most serious and economically important defects caused by clostridia in milk products is the late blowing of semi-hard cheeses.Clostridia occur naturally in soil and can contaminate milk through crops contaminated by dung and soil followed by a less successful silage process, that give them opportunity to grow unaerobically. When Anaerobic conditions occur, such as storage of semi-hard cheese, they ferment lactic acid to butyric acid and the gases CO2 and H2.At the fusion of Arla and MD Foods, a series of changes were conducted on the MPN method for lactic acid fermentation for clostridia in milk. These changes resulted in an increased accuracy due to an increased number of test tubes and the change of media from MRCM to BBB, Bryant & Burkey Broth, that was thought to be more selective for Cl. tyrobutyricum, the organism mostly found in hard cheese. When the number of dairy farmers that were given quality reduction fines increased, the new method was suspected and a validation was conducted.The validation included inoculation of different clostridia and bacillus strains into BBB substrate and enzymatic testing of positive samples with Rapid ID 32A.

Korsförlamning hos häst : fodrets påverkan

The purpose of this thesis has been to gather knowledge about the complaints of tying-up in horses and to show that the importance of feeding. The thesis includes a literature review of tying-up how preventative measures by feeding can be made. In the equine sport, crosscountry, horses occasionally suffers from tying-up, a muscle disease. An increased knowledge about the disease is demanded by riders and trainers as the disease disrupts training and competition of suffered horses. A cross-country horse works very hard in training and during competitions but the work bouts are long enough for the muscle cells to use aerobic pathways in the metabolism.

Clostridium difficile toxins in meat-producing guinea pigs in the highlands of Peru

The guinea pig is an important meat-producing animal in Peru as well as in several other South American countries. They are held in different kinds of systems, from the small backyard breeders with few animals to the large commercial farms with thousands of guinea pigs. One of the major issues at the farms is animals dying of unknown causes. Salmonellosis is often considered as a major cause, but samples for confirmation are rarely taken. It has been known for a long time that Clostridium difficile (C.

Teknisk undersökning : Rötgaskammare för småskalig biogasproduktion

Biogas mainly consists of methane and carbon dioxide, where methane is theenergy-rich gas, and is naturally created when organic matter breaks down in absenceof oxygen, also known as Anaerobic digestion. A biogas plant re-creates the Anaerobicconditions inside a digester where the organic substrate is fed into and digests toproduce biogas. The gas is then used to produce energy by combustion and can beseen as a completely renewable fuel.Today, energy from biogas is used primarily by major stakeholders such asmunicipalities and thus the plants become very large with high investment- andconstruction costs. There are currently few small plants in Sweden, even though thepotential for agriculture and medium-sized to smaller farms to become self-sufficientin terms of electricity and heat is great. Farms have a natural stock of digestibleorganic material in form of manure or crops for example, which are constantlyavailable.

Outnyttjade resurser inom park- och naturvård

As a small and land scarce country, effective waste management is ofoutmost importance in Singapore. In this study the production of biogasthrough Anaerobic digestion from the organic fraction of municipal solidwaste (OFMSW) was compared to incineration of the waste. At the momentalmost all of the OFMSW in Singapore is incinerated. Three differentscenarios were compared to the reference scenario (incineration): one with alarge scale biogas plant that can treat half of all OFMSW in Singapore, onewith a medium scale biogas plant about 15 times smaller than the large oneand one with a small scale biogas plant that can treat waste from e.g. ashopping center or a food center.By using life cycle assessment (LCA) the different scenarios were comparedin terms of global warming potential (GWP), acidification, eutrophication,energy use and land use.

Metanpotential för alger och bioslam blandat med pappersfiber

In this thesis the methane gas potential of three different substrates, two algaes Saccharina latissima and Laminaria digitata and biosludge mixed with paper fiber was studied. This was done by batch experiments in a laboratory environment to examine the gas production and composition of the produced gas.Biogas production is a complex Anaerobic digestion process in which various microorganisms decompose the substrate in steps and at the end produce biogas and a residue. Many factors affect the production of gas, for example the substrate content, temperature and pH in the digester.The analysis of methane potential were divided into two experiments. In experiment 1 substrates were digested along with inoculum from Växjö waste water treatment plant in a temperature of about 37 ?C.

Biogas till kraftvärme på Wapnö : en projektanalys utifrån ett företagsekonomiskt perspektiv

Biogas is a gaseous fuel, rich in methane, produced through a biological route in an Anaerobic digester. A gas engine generates combined heat and power, which can be used at the farm to reduce energy cost. The process also generates a digestate, with better utilization of nutrient compared to cattle manure. The aim of this study is to analyze the profitability of a farm-scale biogas plant for combined heat and power (CHP) at Wapnö. Wapnö is an agriculture company located in the southern part of Sweden.

Environmental impact assessment of energy recovery from food waste in Singapore : comparing biogas production to incineration

As a small and land scarce country, effective waste management is ofoutmost importance in Singapore. In this study the production of biogasthrough Anaerobic digestion from the organic fraction of municipal solidwaste (OFMSW) was compared to incineration of the waste. At the momentalmost all of the OFMSW in Singapore is incinerated. Three differentscenarios were compared to the reference scenario (incineration): one with alarge scale biogas plant that can treat half of all OFMSW in Singapore, onewith a medium scale biogas plant about 15 times smaller than the large oneand one with a small scale biogas plant that can treat waste from e.g. ashopping center or a food center.By using life cycle assessment (LCA) the different scenarios were comparedin terms of global warming potential (GWP), acidification, eutrophication,energy use and land use.

Produktion av Pyrolysolja från kvistrejekt

Fast pyrolysis is a method for converting biomass into three energy rich products: char, gas and bio-oil, where the latter is most interesting.  Pyrolysis is an endothermic process where biomass is heated in an Anaerobic environment and, with the right operating conditions, up to 80 %wt bio-oil can be extracted. Key parameters for fast pyrolysis are: stable reactor temperature (~500°C), short residue time for gas in the reactor (<2 s) and a very high heating rate for the biomass. Today there are several different process solutions for fast pyrolysis, where fluidized beds and rotating cones are most developed. Bio-oil has compared to fossil oil: lower heating value, low pH and also polymerizes with time. Because of this upgrading is desirable for increasing competitiveness.

Analys av system för rening av avloppsvatten i en anaerob membranbioreaktor

The most common way to treat wastewater in Sweden today is by a combination of an activated sludge process and a chemical treatment. These processes are not very energy efficient and may not be the most environmentally friendly. That is why it is interesting to evaluate new alternative methods to see if they can be less harmful to the environment and help to a lower resource consumption. New techniques are tested in a pilot installation at Hammarby Sjöstad, Sjöstadsverket. To be able to evaluate these techniques in a wide perspective system analyses are conducted where different impacts can be considered, advantages and disadvantages in the systems.Five system structures for water treatment have been constructed in Matlab/Simulink in this study.

En validitetsstudie på beeptestet : avseende maximal aerob kapacitet för elitishockeyspelare

Introduction: This study aimed to investigate the validity and reliability of the 20m multistage shuttle run test (MST) for elite ice hockey players as a predictor of the maximal aerobic capacity and the how the result is affected by the players age, aerobic and Anaerobic capacity, body composition and test surface. The purpose of this was to find out the potential of the 20-m shuttle run test as a measuringtool for the maximal aerobic capacity in frequent testing periods during the season. It is very interesting to be able to administer this easily because the competative phase of the season is very long compared to the pre-seasonal phase and earlier studies have shown that the aerobic capacity is being lowered during this competative phase of the season for elite icehockey players.Methods: 34 elite ice hockey players participated in this study (20.0±3.6 yrs, BMI 24.2±1.6 and VO2-max 58.0±4.8 ml O2?kg-1?min-1). During 3-5 days they underwent 2 MST tests (wood and rubber surface), treadmill running with VO2-max assessed with open-circuit technique, Wingate10% and FFM-assessment with underwater-technique.

Biogasproduktion genom tvåstegsrötning av drankvatten

During the 19-century a global warming has been observed, which includes increases in global air and ocean temperatures, widespread melting of ice and snow, and rising global sea level. There is a clear connection between emissions of greenhouse gases caused by the human and the increase in temperature. Climatic changes caused by global warming can be stopped trough decreased emission of fossil fuels, for example by an increased use of biogas. Biogas is a renewable energy source which is produced through Anaerobic (oxygen free) digestion of organic material. The gas is a mixture of methane (CH4) and carbon dioxide (CO2) and can be among others used as fuel in vehicles.

Energianalys av hygieniseringssystem : jämförelse av befintlig pastörisering med integrerad termofil hygienisering på Kungsängens gårds biogasanläggning i Uppsala

The biogas plant Kungsängens gård, owned by Uppsala Vatten och Avfall AB, produces biogas and biomanure from organic household waste, food processing waste and slaughterhouse waste. In year 2012, 4.4 million Nm3 of biogas were produced from 25 200 tons of waste. Before digestion all substrate is sanitized by pasteurization at 70°C in order to kill pathogens. Another method, integrated thermophilic sanitation (ITS), is of interest in order to decrease the energy demand. The method implies that the substrate is sanitized during ten hours in the digestion chamber, where the temperature is 52°C.

Uppvärmningens betydelse för hopphöjd och fem sekunders sprintprestation : En experimentell studie om hur anaerob prestation påverkas av uppvärmningsintensitet

Syfte och frågeställningarStudien genomfördes med syftet att specificera vilken intensitet och duration vid uppvärmning som är optimal för att få ut största möjliga effekt vid anaerob prestation i form av maximalt vertikalhopp och fem sekunders maximal cykelsprint. Studien byggde på tre frågeställningar: På vilket sätt påverkar uppvärmningen prestationen vid ett maximalt vertikalhopp? På vilket sätt påverkar uppvärmningen prestationen vid ett maximalt fem sekunders sprinttest? Vilken uppvärmning är optimal för maximal muskulär explosivitet?MetodDesignen var en kvantitativ experimentell studie som innefattade fyra fysiskt aktiva kvinnor med genomsnittsålder på 24 år. Testerna bestod av nio tillfällen där en slumpad uppvärmning på ergometercykel genomfördes varje gång. Därefter genomfördes tre vertikalhopp, så kallade counter movement jump, på en kraftplatta och tre fem-sekunders sprint (5sCST) på Monarks Peak Bike.

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