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574 Uppsatser om Temperature gradient - Sida 31 av 39

Kolbalansen vid olika skötselstrategier för skogen på Tagels fastighet.

Since the 19th century the concentration of CO2 in the atmosphere hasincreased by 40 percent as an effect of the use of fossil energy sources.Increased concentration of CO2 will likely lead to increased temperature,changes in precipitation, rising sea level and increased frequency of extremeweather like storm events. A step to reduce emissions of CO2 and mitigateclimate change, for the property of Tagel, can be to adopt new silviculturalstrategies and analyse which is the most effective. As a result of that, threescenarios was produced, business-as-usual (BAU), increased set aside landand energy. An introduction of windpower at Tagels estate (property) andeffects on carbon balance was also examined. By using the Heureka systemand LCA-analysis in this study, it showed that the scenario of increased setaside land was the most efficient way to reduce carbon dioxide (CO2)emissions for the analysed period of 100 years.

The welfare of the laboratory mouse : comparison in development of mouse pups in three different individual ventilated cage (IVC) systems

Today the individual ventilated cage system (IVC-system) is a commonly used housing system for mice in research facilities. IVC systems have HEPA- filters and are designed to control both supply and exhausted air at cage level, as well as temperature and relative humidity in the cages. This creates an optimal environment for the mouse and at the same time a protection against the risk of cross-infection between cages and the outside environment. The aim of this study was to evaluate the health and welfare of breeding females and pups of two different strains of laboratory mice (NMRI nude mice and C57BL/6N) in three different kinds of IVC-systems; Arrowmight, Allentown and Tecniplast. The NMRI nude (Nu) females gave birth to 18 litters in Allentown, 16 litters in Arrowmight and 15 litters in Tecniplast.

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.

Provning av parallellkopplade hydraulpumpar i hjullastare

Volvo Construction Equipment is a world leading company in construction machinery. Tomaintain the best products, development is prioritized. The master thesis regards sound reductionof the hydraulic system on a wheel loader. The background to the master thesis is asimulation made on the hydraulic system, performed autumn 2005. The result of the simulationshows that the energy of the pressure ripple is reduced when the paralleled hydraulicpumps are phase shifted and reduces each others pump pulsations.

When does the protein profile in milk normalize after antibiotic treatment against clinical mastitis?

Concentration of protein in bovine milk is one of the most significant milk quality parameters, to a large extent determining the price for milk to the producer. Mastitis is a common disease among dairy cows, negatively affecting not only milk yield but also milk protein composition. Milk from mastitic cows tends to have lower cheese yield, negatively affected processability properties and sensory quality, due to changed protein quality and composition. Poorer milk protein quality would have an economically negative impact on dairy industry. Only few studies have investigated the short term effects of mastitis on milk protein composition.

Anestesi av ödlor

The anatomy and physiology of reptiles and mammals are in many ways different, and will therefore possibly complicate anesthetic administration. Lizards are ectothermic and one should keep in mind that a decrease in the lizard?s environmental temperature may result in reductions in anesthetic metabolism. Respiratory depression is a profound problem because lizards lack a diaphragm, making inhalation and expiration completely active processes. This, in combination with cardiac shunting and breath holding makes the effects of anesthesia unpredictable.

Dogs on the move : a study of the travel habits of Swedish dogs and their owners? awareness of infectious diseases.

ABSTRACTThe principal aim of the study was to compare the feeding behaviour of cattle, sheep and goats on pasture and explain any differences between speices. Furthermore, I compared foraging behaviour between dry season and the beginning of the rainy season, in order to see any relationships between weather and behaviour.The study was carried out in Shompole in southern Kenya. Behavioural data were collected by observing herds of cattle, sheep and goats on pasture. The livestock were herded on pasture during the days and kept in bomas, where people live, during the nights. The weather in Shompole is characterized by high ambient temperature and low, bimodal rainfall.

Effekt av sönderdelningsgrad och planteringsdjup på uppkomsten från rhizom av Tussilago farfara :

Tussilago farfara, coltsfoot, is a troublesome perennial weed with deep lying rhizome, which can vegetatively generate new plants. The mechanical control of coltsfoot that is used today, "starvation", which consists of several cultivations of the soil, which fragmentises the rhizome. This results in production of new shoots, which leads to depletion of nutrient resources; as long the new plant is not allowed to establish. However, very little research has been done to investigate how the starving technique affects the regenerative ability of coltsfoot. The purpose of this experiment with coltsfoot was to investigate how fragmentation and burial depths affect the time of emergence, number of emerged shoots per rhizome fragment, number of shoots per node, and if the germination ability within nodes changes during the experiment.

Kaliumgödsling på torvmark - effekt på tillväxten hos planterade granar (Picea abies)

Peat  lands  are  a  great  potential  resource  for  increased  forest  growth  in  Sweden, there  are  approximately  6.5  million  hectares  of  peat  lands,  whereof  around  70% produce less wood than one m3sk/ha and year and are therefore classed as forest waste  land.  There  are  over  200  000  hectares  of  peat  land  that  is  already  drained and  wooded,  and  that may  be  suitable  for  fertilization.  Forest  production  on  peat soils  usually  requires  drainage  and  fertilization.  Dewatering  requires  ditching  the area, so that the roots can have access to oxygen. Nitrogen is often abundant in the peat but other nutrients; especially potassium is in short supply. The  purpose  of  this  work  was  to examine  the effects  of  potassium  fertilization  on the  growth  of  spruces  that  were  planted  on  drained  peat  land  and  how  different amount of fertilizers affects the growth. Potassium deficiency is strongly growth inhibiting, since potassium is important for substance  transport  in  the  tree.  Potassium  is  also  important  for  the  carbohydrate formation, and because increasing the sugar content of the cells constitutes a lower freezing temperature does potassium availability in the soil play a major role in the winter  resistance  of  many  species.  Potassium  is  not  found  in  any  organic compounds in the tree, but is present in cell and tissue fluids. A fertilization trial was started in 1978 in Siljansfors Experimental Forest. The plots in the experiment were fertilized with different amounts of potassium and one plot was  left  without  fertilization.  All  plots  that  were  fertilized  with  potassium  grew considerably better than the unfertilized plot. The difference in production between the unfertilized plot and the plot that received the most potassium was 7.2 m3sk/ha and year. The unfertilized plot can still be classified as waste land. The theoretical production capacity was estimated using a Swedish system for site quality  estimation  of  wetlands  after  ditching  (dikningsbonitering).  The  plot  with most  potassium  produced  after  fertilizationaproximately  in  level  with  theoretical estimations.  Key  words:  Peat  land,  Fertilization,  Ditching,  Growth,  site  quality..

Tidig postoperativ övervakning av smådjur : förekomst av standardiserade rutiner

Background. Anesthetic-related death in small animal anesthesia is about ten times more common than in human anesthesia. Recent research identifies the early postoperative period as particularly risky and highlights the need for regular and careful monitoring of the veterinary patient during this period. Objective. The aims of this study were to investigate whether there are standard procedures in terms of regulated routine patient observations and record-keeping during the early postoperative period at Swedish veterinary clinics, and if there are any guidelines for monitoring the veterinary patient during recovery. Methods. A small survey including ten Swedish veterinary clinics was carried out as well as a literature review. Results.

En studie av fysiska, organisatoriska och individuella riskfaktorer hos arbetstagare med datorarbete

Musculoskeletal disorders (MSD) are common in individuals with computer based work. Thecurrently known risk factors for these disorders is in the literature derived to physical,organizational and individual factors. A recent survey of three working groups at a companyin Stockholm explored that more than 50% of the employees had neck and shoulder problems.Aim: The study aims to create a better understanding for the current musculoskeletalproblems at the company. Such an understanding is created by examining the physical,organizational and individual risk factors in the workplace and the result can provide a goodbasis for intervention proposals.Method: In order to answer the aim of the study the authors chosed to use both qualitativeand quantitative methods of data collection through interviews and questionnaire survey. Theinterview and questionnaire was designed to create both a specific and comprehensive pictureof the physical, organizational and individual risk factors having a bearing effect on theexisting MSD problem.Result: Seven categories were compiled from interviews, which largely deals with the factthat high demands can lead to behaviors that may pose a significant risk for the occurrence ofMSD.

Passivhus av helväggselement i träull

Environmental destruction is a growing problem in our world. Almost every day there are new reports concerning that we have to do something about the greenhouse gasses. Simultaneously is the human constantly more eager to have a life with higher standards and therefore uses more energy. The environment is a question that is highly up-to-date and more people try to find solutions on how to save our planet. One way to decrease the energy demand is to build passive houses, where the houses don?t have any active heating.

Wallenbergare : En jämförelse i sensorisk kvalitet

Inledning Wallenbergare var från början en elegant restaurangmaträtt bestående av en panerad kalvfärsbiff serverad med potatispuré, ärtor, lingon och skirat smör. Rätten torde vara uppkallad efter häradshövdingen Marcus Wallenberg någon gång under 1930- talet. Det finns många historier om Wallenbergarens uppkomst men ingen tycks veta med säkerhet vem som serverade den för alldra första gången.Syfte Syftet med denna uppsats var att undersöka hur val av styckningsdetalj, kryddning, temperatur och mixning påverkar den sensoriska kvaliteten i en Wallenbergare.Metod/material De tre metoder som användes under denna studie var en provmatlagning med en större mängd av variabler, en enkätundersökning gällande tidigare erfarenheter och uppfattningar om Wallenbergare samt en sensorisk bedömning av biffens sensoriska kvalitet.Resultat För att Wallenbergaren ska uppnå en konsistens av hög sensorisk kvalitet bör denna bestå av 75 % malt kalvinnanlår, 25 % kalvbräss, äggula, grädde och salt. En Wallenbergare bör endast smaksättas med salt och nymald vitpeppar.Provernas samtliga ingredienser skall vara väl kylda för att uppnå högsta sensoriska kvalitet. De prover som blandades med handkraft erhöll en lägre sensorisk kvalitet än de prover som blandades mekaniskt.

Fuktåterföring i roterande värmeväxlare

För att ha en chans att ändra trenden med ökande utsläpp av växthusgaser är internationella samarbeten nödvändiga. Därför har EU genom miljökvalitetsmålet Begränsad Miljöpåverkan satt krav på högsta tillåtna utsläpp av växthusgaser. Att sänka energianvändningen för upp- värmning är ett steg i att även sänka utsläpp av koldioxid, som är en av växthusgaserna. Sänkning av energianvändning kan göras på flera sätt, bl.a. genom att öka tjockleken på isoleringen eller återvinna värmen i frånluften. Men dessa åtgärder ska inte helt okritiskt göras.

Grazing behavior of Ankole and Boran cattle in an improved herding production system

To be able to provide the growing human population with food, the productivity of the animals as well as land use needs to be improved and intensified. Hence, understanding the behavior of animals is crucial both for animal welfare and productivity as well as the management of the cattle. There are many factors affecting the grazing behavior of cattle in tropical conditions, such as human-animal interactions, herd management, breed, season and temperature. The purpose of this study was to investigate the grazing behavior of two tropical cattle breeds, Ankole and Boran cattle. Kenyan Boran belongs to a zebu type of cattle and is preferred to many other breeds due to the higher productive and reproductive capacity and adaptability to tropical conditions.

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