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57 Uppsatser om Crude Oils - Sida 4 av 4

Latent värmelagring i vattenburet uppvärmningssystem med elpanna för byggnadsapplikationer

Latent heat storage is a way to store thermal energy when a phase change material undergoes a phase change. The advantage of latent heat storage is the capability to store more energy per mass unit than other heat storage methods. The most commonly used phase change in latent heat storage is the transition between solid and liquid. Phase change materials can be divided into organics, inorganics and eutectics.In the Nordic electricity market the price of electricity is set every hour by Nordpool spot, which leads to price fluctuations because of changes in demand. The main goal of this report is to create a latent heat storage system in a single-family home and investigate the possibility to save money by charging the latent heat storage system when the price of electricity is low, and discharge when the price is high.The thermodynamic model consisted of a ?tube-in-tube? heat exchanger with phase change material in the outer tube and water as the heat transfer fluid in the inner tube.

Uppfödning av gyltor till hållbara suggor

Half of Sweden?s 140 000-150 000 sows are culled and replaced by 75 000 gilts annually. Culling of old sows is necessary and allows new breeding material to enter the herd. However, many of the culled sows are young, and have not yet become profitable at the time for culling. Therefore, it is an important question for the pig industry, how to raise gilts to sows with a high and sustainable production level.

Yeast in forage crops and silage aerobic stability at 15 Swedish dairy farms

This study investigates the role of yeast in green crop and its impact on the aerobic stability of silage. Fresh crop was collected from 15 farms in southern and middle parts of Sweden during the summer 2014; samples from the primary harvest was collected from eight farms and samples from the first regrowth harvest was collected from seven farms. The grass was ensiled in 1.7 l glass silos. After three months of ensiling, silos were opened and silages were stored aerobically for 10 days. Samples from both harvests were ensiled in completely airtight silos, but samples from the second harvest were also ensiled in slightly ventilated silos. Chemical analyses and yeast counts were performed for fresh crop and silage.

Påverkan på Valboåsen från verksamheter inom Svedens industriområde samt närliggande områden : hot mot grundvattnets kvalitet och kvantitet?

The aim of this work was to find out what potential contaminants from roads, residential area and businesses within Svedens industrial area that can affect groundwater quality and quantity. Data collection was from SGU, VISS, internal material from Gävleborg county Administrative Board and Gävle municipality archive. GIS software ArcGIS was used to create the map images in the work. The studied area is located approximately ten kilometers west of Gävle city and consists of the esker Valboåsen, which is a glacifluvial deposit that in its central parts consist of coarse material that is overlaid by sand, clay and silt. North of esker Valboåsen there are the river Gavleån which has an inflow to the groundwater in the esker. This inflow represents the largest part of the groundwater recharge.

Nutrient efficiency in Swedish dairy cows fed total mixed rations or partial mixed rations

The relatively poor economy in European dairy farming might be improved from efficient feeding systems and dietary management. Increasing herd sizes and transition to loose housing systems in Sweden, increases the possibilities for other feeding systems than separate feeding that is the traditional feeding system in Sweden. Other possible feeding systems are partial mixed ration (PMR) and total mixed ration (TMR), where the TMR system sometimes is associated with overfeeding and thereby increased environmental impact and high feed cost. Diets providing nutrients above or below animal requirements are considered as unbalanced, which in turn are associated with reductions in health, fertility and milk production. On the other hand, a balanced feed ration improves feed efficiency, nitrogen utilization and profitability.

Böklåda med torv på rastgårdsytan i ekologisk slaktsvinsproduktion : effekter på beteende och emission av kväve (NH3 och N2O)

In organic animal production, synthetic amino acids are not allowed. Therefore, a higher level of crude protein is needed in the diet to pigs, which lead to more nitrogen (N) excreted in the faeces and urine. N can be emitted to the air in the form of e.g. ammonia (NH3), which contributes to eutrophication and acidification and as nitrous oxide (N2O), which is a very potent greenhouse gas. The emission of N can be reduced by e.g.

Magnesium chloride in dry cow silage to prevent hypocalcaemia

Milk fever, or parturient paresis, is the second most common disease in Swedish dairy cows. The disorder is associated with the onset of lactation when some cows are unable to meet the metabolic demands of calcium to support milk production and therefore develop a state of hypocalcaemia. Clinical hypocalcaemia (milk fever) may lead to coma and death in severe cases but subclinical hypocalcaemia has also been shown to have negative effects on e.g. feed intake and production and to increase the susceptibility of the cow to develop secondary diseases. The nutritional strategy applied precalving is of great importance in preventing milk fever and e.g.

Svampar associerade med raps : betydelse för uppkomst och grödetablering

Oilseed rape is an important crop in Sweden and is grown on about 90000 ha today. The interest in oil seed pro-duction is increasing because of growing demand and high prices for oil seed both in Sweden and Europe. However, an increased intensity in the oil seed production can bring higher risk of yield losses due to fungal diseases. The purpose of this study was to investigate what different fungi are associated with oilseed rape under field conditions and if their incidence is correlated to crop establishment problems. This study was carried out in three parts: 1) investigations on fungal community structure in roots and rhizosphere soils from young spring- and winter rape plants sampled in failed respectively good establishment patches in four fields, 2) investigations on the pathogenicity of fungi isolated from oilseed rape in controlled environment and 3) investigations on the effect of different fungicide seed treatments on germination and early plant development in a field soil naturally infested with damping off- and Verticillium wilt pathogens. The studies on community structure using a combined approach of standard fungal isolation techniques and DNA based methods revealed a high fungal diversity in three out of four studied fields of spring rape and winter rape. For some unknown reason, very few fungal species were identified from the fourth field.

Om förtryckande strukturer

This paper is a critique of an article in the Swedish magazine Filosofisk Tidskrift (Philosophical Magazine), in which professor Per Bauhn maintains that there is something wrong with having a group perspective in moral and political matters. In this article Bauhn makes three conclusions. The first one is that you violate Hume's law if you draw the conclusion that something is an oppression only from descriptive premises, which for example communitarians does according to Bauhn. He argues that ?oppression? is a normative term, and therefore it requires at least one normative premise.

Agroprotein som fodermedel till slaktkyckling

Destillers dried grains with soluble (DDGS) is a by-product when producing ethanol. DDGS from wheat has a high crude protein content and a good amino acid profile, which makes it an interesting feed ingredient for poultry. The disadvantage of feeding DDGS from wheat to poultry is that it also contains a high fiber content that chickens don?t have the ability to break down. Lantmännen Agroetanol has developed a new protein feedstuff from DDGS by extracting wheat protein from DDGS, the product name is Agroprotein SD.

Peas as feed for dairy cows

AbstractAn approaching overproduction of cereals and a future uncertain supply of non genetic modified vegetable protein feedstuffs have increased the interest in an expansion of the domestic production of protein feedstuffs in Norway. Besides rapeseed (Brassica campestris), peas (Pisum sativum) may be the most suitable crop for this purpose. Peas are characterized by having a relatively high content of crude protein, ranging between 20-26%, a high content of starch, 42-51%, and a low content of fat. In general, the energy value for peas is higher than for barley but lower than for rapeseed and soybean meal.Pea protein consists of albumins and globulins to 85-100%, which leads to the fact that a large part of the pea protein is soluble and degradable in the rumen. Starch in peas is on the other hand to a large extent resistant to rumen degradation compared to starch from other starch rich feedstuffs.

Etanolmarknaden i Brasilien : etanol som fordonsbränsle

According to the EC fuel regulations 2 % bio fuel has to be blended in all fuel by the year 2005, and 5.75 % by the year 2010, which means ethanol for gasoline driven vehicles, so there will be a substantial demand for ethanol. Brazil already has an established industry for producing ethanol and is the leading producer and exporter of fuel ethanol. My purpose with this paper is to investigate why Brazil decided to develop ethanol production on a large-scale operation and to find out today?s situation. Focus will mainly be on ethanol production with sugarcane as a feedstock.

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