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697 Uppsatser om Wood density - Sida 16 av 47

Förändrad aptering av massaved från 3- till 4-meterslängder vid gallring inom Södra : en systemanalys av effekter från avverkning till levererad virkesråvara

The costs of logging and of transportation with truck are dominating the total cost of wood delivered at industry. To support the profitability for the members' forestry the processing and handling with the timber has to be as efficient as possible. Increased length of pulpwood in thinning is one conduct that can result in higher productivity and/or lower costs. The study is scaled as a system analysis with the aim to exemplify the differences between working with 3- and 4-meter as standard length of pulpwood, related to biological aspects, timber receipts, cost of logging and cost of transportation with truck. Important aspects are if the change is technically and biologically feasible and economically profitable.

Den bäcknära zonen vid små skogliga vattendrag i Värmland : generell beskrivning, förekomst av traktorspår samt kvicksilverhalter i körpåverkat ytvatten

Forest streams and the associated riparian zones are sensitive to disturbances and changes that occur within these riparian areas. Particularly sensitive are small streams of low order, which will have large impacts down-stream. The disturbances that occur in the riparian zones are reflected quickly in the stream. Driving with forestry machines in the riparian zone will have detrimental effects to the soil and water. Driving the machines will lead to changes in the mineral soil composition, resulting in the reduction of porosity, less infiltration, compaction, and an increased bulk density.

Alternativa finansieringsmöjligheter av företagsfastigheter

It is essential to reuse- and recycles residues to decrease the amount of deposit materials and reach sustainable energy use. Two ways to work towards this is to recycle wood ashes to the forest as nutrient compensation and extract biogas from combustion of biomass.The aim with this study was to decide whether wood ashes that been used for biogas upgrading with accelerated carbonation also can be used as a nutrient compensation in the woods according to recommendations from the Swedish Forest Agency (Skogsstyrelsen).The ashes that were used in this study came from Johan Andersson who works at JTI in Uppsala, who also treated the ashes with biogas. The ashes have, in both untreated and treated condition, been analyzed in this study according to contents of elements, leaching properties, hardening properties and contents of crystalline phases, to evaluate what impact carbonation with biogas has on the ashes.The accelerated carbonation led to hardening of the ash, and decreased amount of CaO- and increased amount of CaCO3. The CO2-uptake also entails a dilution of the elements, and the content of nutrients and trace elements decreases. However the results show an indication of an uptake of S from the biogas to the ash, since the dilution had a smaller impact on S than the rest of the elements.

?R KUSTN?RA ALK?RR I BOHUSL?N ETT ?BLUE CARBON? HABITAT?

In coastal wetlands carbon/organic matter can be stored for long periods of time thanks to, among other things, the presence of water which slows down the decomposition. Because of this, restauration and management of such habitats have the potential to decrease the emission of greenhouse gasses and help mitigate climate. Internationally these environments are called ?blue carbon? ecosystems. In Sweden, alder (Alnus glutinosa and Alnus incanata) covered wetlands along the coast is a nature type that potentially could function as a ?blue carbon? habitat.

Variationer av klor, svavel och aska i havrekärna : odlingsfaktorernas inverkan på havrens bränsleegenskaper

The increasing oil prices during the last years have made it profitable to use cereal grains as a fuel. When compared with wood, cereals contain higher amounts of Cl, S and ash. The Cl and S content makes the gases from cereal combustion more corrosive than gases from wood combustion. The goal of this master thesis was to find out the variation of Cl, S and ash content for oat grain grown under different conditions. Oats was chosen because in Sweden it's considered as the cereal with the best fuel qualities.

Energianalys av etanolproduktion : en fallstudie av Lantmännen Agroetanols produktionssystem i Norrköping

In this thesis an energy analysis of ethanol production at the ethanol plant of Lantmännen Agroetanol in Norrköping has been performed. The ethanol plant has been studied in combination with Händelöverket, the combined heat and power plant which provides the ethanol process with steam. The purpose of this study was to determine the energy consumption for the whole production chain from grain to ethanol. The analysis has included the energy consumption for cultivation of grain, production of chemicals, the production chain for wood chips, the steam production and the ethanol plant. The grain and wood chips are both considered raw materials there for the energy content in these are not included as energy input in the system.

Energianalys av etanolproduktion : en fallstudie av Lantmännen Agroetanols produktionssystem i Norrköping

In this thesis an energy analysis of ethanol production at the ethanol plant of Lantmännen Agroetanol in Norrköping has been performed. The ethanol plant has been studied in combination with Händelöverket, the combined heat and power plant which provides the ethanol process with steam. The purpose of this study was to determine the energy consumption for the whole production chain from grain to ethanol. The analysis has included the energy consumption for cultivation of grain, production of chemicals, the production chain for wood chips, the steam production and the ethanol plant. The grain and wood chips are both considered raw materials there for the energy content in these are not included as energy input in the system.

Tillämpning av nya beräkningsmetoder för branddimensionering av  träkonstruktioner - analyser och jämförelser

To build high-rise buildings made of timber has for long been limited by national laws, due to the lack of knowledge in engineering solutions. Frame structures made of wood has for a long time been associated with major fire hazards and consequently lower safety and this connection is still being made today. The increased environmental awareness in recent years has contributed to the exploitation of indigenous building materials, including wood from our own Swedish forests and has become increasingly common. Increased knowledge about how structures behave in fire and how they can be protected in order to achieve safe timber structures has resulted in a growing interest in these structures in the construction industry. Research in the area is constantly updated and new laws allow any number of storeys in wooden buildings in Sweden as long as the performance requirements are fulfilled.The main part of this work has involved calculations of the fire resistance and load bearing capacity of floor and wall constructions.

Kvalitet och ekonomi i utförandet av förstagallring baserat på olika gallrings- och underväxtröjningsprogram :

Stora Enso Skog has a long term contract regarding felling rights and silvicultural activities on forest owned by Bergvik Skog. In the autumn 2006, Bergvik Skog proposed a new thinning program, ?Bergvikgallring?. The new program implied an increased focus on extraction of smaller trees compared to the present thinning program, Stora Enso Skog?s ?Kvalitetsgallring?.

Amyloid beta inducerad klyvning av NG2 medierad via LRP-1 receptorn

Bakgrund: Deposition av fibrillär amyloid beta 1-42 (A?) i hjärnan är ett välkänt kännetecken för den neurodegenerativa sjukdomen Alzheimer?s (AD). Dessa ansamlingar påverkar pericyter, en celltyp involverad i blodkärlsfunktion och upprätthållande av blodhjärnbarriären (BBB). Pericyter uttrycker både receptorn low density lipoprotein receptor related protein 1 (LRP-1) till vilken A?1-42 binder, och proteoglykanet NG2.

Sorterar skotaren bort det timmer som skördaren har tillrett? :

The efficiency of the harvesters work is more often reviewed, than the work of the forwarders. In a local Stora Enso office the differences between the harvesters reported volume of timber, and the actual volume delivered to the industry had been noticed. Therefore, the decision was made to do a review on the forwarders work. The review was conducted together with a worker from Vmf Qbera, who is working daily with wood measurement, in order to get a valid evaluation of the logs. Eight sites were included in the survey, and on each site 50 logs were marked. Approximately one third of the marked logs were pulpwood, and the remaining logs marked were timber.

Sittande i väntan på hållbarhet - Nyhaga vilfåtölj

The Sitting while waiting for sustainability project goal was to make a functional model for a resting chair and to make it by using furniture and artefacts as material. A try of understanding the process of re-design and to use it to design was driving the project through. The result was a prototype made out of a bed frame and 18 pair of jeans and with details made out of leather..

Effekter av gödsling i äldre tallbestånd på renbetesväxter i fält- och bottenskikt :

Reindeer husbandry and Forestry are both area related industries and will in big extent use the same lands. Conflicts often arise because of that the industries have different interests. Many of the activities done by the forestry influences the reindeer husbandry in an undesirable way, simultaneously as the reindeer husbandry activities can have negative consequences for the forestry. One such forestry activity is fertilization. It was during the 1960´s forest fertilization began to be practiced and the reason was that the increase in growth that the fertilization gave could be able to cover for the future shortage in wood many feared. During the 1970´s when the fertilizing activities were most intensive about 200 000 ha was fertilized annually.

Brandrelaterade insekters lokala artrikedom i förhållande till olika miljövariabler : Fokus på betydelsen av konnektivitet på brandfält i boreal skog i Västerbottens län

The last century, forest fires have decreased in frequency due to efficient fire-suppression along with the growth of the industrial forestry. Since 1990, fire has been reintroduced under controlled forms to recreate burnt habitats. Many species that are dependent on, or benefits from, forest fires have increased since fire was reintroduced. The importance of connectivity is often addressed in ecological research. This is particularly important for species dependent on short-lived habitats such as burnt forests.

Kraftvärmeverk i glesbygd - en möjlighet?

Our purpose in this paper is to examine if there is any profitability for a company with a factory in the timber industry to invest in a combined heat and power, CHP. Based on analysis and the results that the paper generates, we will give Derome AB a suggestion on how it is a profitable investment or not to installing in a CHP.By investing in a CHP plant, you can get a high efficiency, which means that companies can use their resources more effectively. The Swedish wood industry has by-products of production that can be used for combustion in their boiler which is an advantage.The essay is a qualitative study where we have a case company, Derome AB. In this company, we interviewed two employees who have knowledge in the study. They have helped us to provide information and data about their business.We chose to use the pay-off- and the net present value method, NPV, to see if there are profitable advantages for the investment.

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