Sök:

Sökresultat:

249 Uppsatser om Zink layer - Sida 5 av 17

Vindfällning, tillväxt och plantuppslag i en 13-årig granskärm i Medelpad :

The interest for alternative forest regeneration methods increased significantly during the 1990´s after 50 years dominance of the clear-cutting system (Holgén & Hånell 2000). One reason for this was that clear-cutting was being more and more questioned by different envi-ronmental organizations and because the forest sector for economical reasons wanted to find cheaper ways to regenerate forests. In the beginning of the 1990´s two shelterwood experi-ments were established in a joint effort by Svenska Cellulosa Aktiebolaget (SCA) and the Dept of Silviculture, Swedish University of Agricultural Sciences (SLU). The experiments include various forms of cutting and shelterwood densities and represent productive spruce forests in central and north Sweden (Roggsjön in the province of Medelpad and Skikkis-jöberg in the province of Västerbotten, respectively ). The experiment next to Roggsjön has been reported earlier in three MSc theses, and is also the focus of this thesis.

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.

Effekt av spädningsvätska på spermiemembranintegritet analyserad med NucleoCounter SP-100 :

This study is a part of a larger project where the aim has been to evaluate different methods to assure the quality in stallion semen, due to the fact that some stallions in horse breeding have poor semen quality. The increased use of transport semen requires new methods to ensure good semen quality. In this part of the project the viability and concentration in fresh and cooled semen was examined with NucleoCounter SP-100. A comparison between two different commercially available semen extenders, Kenney?s and INRA 96, was made.

Risk för metallspridning vid efterbehandling av en zinkgruva

Vittring av pyrit och andra sulfidmineraler orsakar stora miljöproblem i form av ett surt lakvatten (AMD) och höga halter tungmetaller. Svärtträskgruvan är en nedlagd zinkgruva varifrån lakvatten innehållande metaller såsom zink, kadmium och nickel bildas från oxiderande gråbergsdeponier som finns i området och sprids till recipienten. I dagsläget samlas allt lakvatten till en utsläppspunkt där det behandlas med kalk och järnsulfat innan det når en sedimentationsbassäng. Sedimentationsbassängen mynnar sedan via ett utlopp direkt ut i Börtingbäcken. En effekt av detta är att pH-värdet i den övre delen av Börtingbäcken har ökat.Flera mindre gråbergsdeponier är idag utspridda över gruvområdet.

137Cesium i myrsamhällen i Gävleborgs län 24 årefter Tjernobylolyckan

24 years have passed since the Chernobyl accident when radionuclides were spread over largeareas of Europe, including the Scandinavian countries. Today, measurable activities of 137Csare still observed in many Swedish ecosystems.Ants (belonging to the order Hymenoptera) are social insects which collect organic materialfrom a large area around their nests. This study focuses on the 137Cs activity in ant nests andthe cesium accumulation in these nests. The aims were (1) to estimate the 137Cs fall-out in1986, (2) estimate the radiation exposure of ants and (3) find how 137Cs is distributed in an anthill. Seven ant hills (occupied by the species Formica polyctena) were studied near the villageof Hille, situated north of the city of Gävle in central Sweden.

Laborationsmätning av vindtäthetens betydelse för en väggs U-värde

To fulfill the climate target that EU and the Swedish government have decided to apply, it becomes increasingly important that the energy efficiency of existing buildings and making new buildings energy efficient as possible. Of Sweden?s total energy consumption in 2011 was 40% used by residential and service. Of the 40% of the energy consumption was 60% used for heating and domestic hot water. A report from year 2012 shows that one reason why the heating volume is so great could be due to underestimating on the energy consumption for the heating in the planning of the building.

Att arbeta med webbaserad sfi-undervisning : Sfi-elevers syn på internetbaserad undervisning som komplement till lärarledda lektioner

What are the basic thoughts formulated in the Heraclitean fragments? A cosmology, a philosophy of nature, the idea that all can be reduced to a single substance? There is always a risk that Heraclitus is fitted into a thought pattern he doesn?t belong to, if we ? from our present horizon ? focus on continuity in an attempt to frame his thinking as part of an overall progress, running from the so-called pre-Socratics to Aristotle, in the history of philosophy. If we picture the dawn of Western civilization as an early development of scientific thinking, built on a gradual and continuous growth of knowledge, we will easily go astray as we try to discover the Greek origins of philosophy. Assuming, for example, that the readings of Heraclitus as a natural philosopher have come to a dead end, can we approach the fragments from a different angle?The aim of this paper is not to give a systematized reading of all the remaining fragments of Heraclitus, but neither to necessarily contradict the various interpretations that emphasise how these shattered remains reflect a coherent philosophy.

Optimering av sotningsfrekvens i biobränsleeldad CFB-panna : panna 5, Mälarenergi AB, Västerås

During the past 30 years the fuels for energy production in heating and power plants have changed. Fossil fuels have decreased in usage whereas bio fuels in Sweden have increased with 60% since the 1970's. Different fuels affects combustion and the release of various substances and particles into the flue gas. This is caused by the diverse components and chemical structures of fossil fuels and bio fuels. When the flue gas leave the combustion chamber and enters the path to the chimney particles in the gas are being transported out of the combustion chamber.

Utveckling av beslutsstöd för kreditvärdighet

The aim is to develop a new decision-making model for credit-loans. The model will be specific for credit applicants of the OKQ8 bank, becauseit is based on data of earlier applicants of credit from the client (the bank). The final model is, in effect, functional enough to use informationabout a new applicant as input, and predict the outcome to either the good risk group or the bad risk group based on the applicant?s properties.The prediction may then lay the foundation for the decision to grant or deny credit loan.Because of the skewed distribution in the response variable, different sampling techniques are evaluated. These include oversampling with SMOTE, random undersampling and pure oversampling in the form of scalar weighting of the minority class.

Solär Tragedi : Herakleitos Fragm 94

What are the basic thoughts formulated in the Heraclitean fragments? A cosmology, a philosophy of nature, the idea that all can be reduced to a single substance? There is always a risk that Heraclitus is fitted into a thought pattern he doesn?t belong to, if we ? from our present horizon ? focus on continuity in an attempt to frame his thinking as part of an overall progress, running from the so-called pre-Socratics to Aristotle, in the history of philosophy. If we picture the dawn of Western civilization as an early development of scientific thinking, built on a gradual and continuous growth of knowledge, we will easily go astray as we try to discover the Greek origins of philosophy. Assuming, for example, that the readings of Heraclitus as a natural philosopher have come to a dead end, can we approach the fragments from a different angle?The aim of this paper is not to give a systematized reading of all the remaining fragments of Heraclitus, but neither to necessarily contradict the various interpretations that emphasise how these shattered remains reflect a coherent philosophy.

Utveckling av en HBV/PULS-model med sammanfogade markfuktighets- och responsrutiner

Soil properties affect the chemical composition of soil water. When studying transport of chemical substances through a basin, it is therefore important to know from which soil layer the main part of the runoff is generated. The aim of this study is to develop an HBV/PULSE model with merged soil moisture and response routines, which generates good approximations of groundwater levels. It should be possible to extend the model to simulate transport of substances and take into account which soil layer the groundwater level is currently in. The hydrological version of HBV/PULSE is used since there is no need to account for pH or alcalinity at this stage.

Rening av oljeförorenat vatten med torvabsorbent

Hässleholms Renhållare AB är ett avfallsbolag som innehar en oljebehandlingsanläggning på deras centrala avfallsanläggning i Vankiva. På oljebehandlingsanläggningen tar de emot slam från oljeavskiljare och bilvårdsanläggningar samt i mindre mängd förorenade massor. Från behandlingsanläggningen utgår det en vattenfas som leds via ett avloppssystem vidare till det lokala behandlingssystemet för lakvattnet. I bolagets tillstånd för Vankiva avfallsanläggning har det föreskrivits att varje delflöde till den lokala behandlingen av lakvattnet måste kontrolleras för att inte fastställda gränsvärden för olja och tungmetaller ska överskridas. Under våren 2006 kompletterades avloppssystemet från oljebehandlingsanläggningen till lakvattenbehandlingen med en filterbrunn.

Nutritions betydelse för förbyggande av trycksår hos patienter över 65 år med genomgången höftfraktur

Trycksår är en komplikation hos patienter med höftfraktur som ofta tillskrivs sängläge men som kan uppstå vid olika långvariga inaktivitet och belastningstillstånd. Syftet med denna litteraturstudie var att undersöka eventuellt sambandet mellan nutrition och förebyggandet av trycksår hos patienter över 65 år med genomgången höftfraktur. En systematisk databassökning har skett i Pubmed och Cinahl. Denna studie genomfördes för att söka relevanta vetenskapliga artiklar och sju artiklar selekterades. Författarna fann att olika näringsämnen framförallt serumalbumin, arginin, zink, vitamin C kan påverka sårläkningsprocessen.

Kvalitén hos SLC-selekterad hingstsperma : mitokondriella membranpotentialen och produktion av ROS

Studiens målsättning var att utvärdera kvalitén hos hingstsperma selekterad med hjälp av Single Layer Centrifugation (SLC), med huvudsyftet att studera den mitokondriella membranpotentialen (??m) och förekomsten av reaktiva syreföreningar (ROS) hos hingstspermier före och efter SLC. Ett insemineringsförsök med SLC selekterad och rutinspädd sperma genomfördes även på ett litet antal ston, men inga slutsatser kunde dras av resultaten. Humanstudier har visat att spermier med låg ??m mer frekvent har återfunnits hos män med fertilitetsproblem. Mätning av ??m har gjorts genom att tillsätta den lipofila JC-1, vilket i både studier på både humana- och ekvina spermier har visat sig vara en känslig metod för att särskilja spermier med låg respektive hög ??m.

PlusTak

Today´s roofing of dwelling houses is a very time consuming procedure, which includes a lot of different steps on the construction site. Not only does it cost a lot of money, but often do problems with rot and mold occur in the attics of houses today. The use of prefabricated modules has seen a great breakthrough in the field of construction of dwelling houses; at least when it comes to foundations and walls, where this type of approach makes the construction process way more efficient. What no one previous has succeeded to develop is a corresponding system for roofs that meets the demands of a dwelling house. Accordingly the goal of PlusTak has been to come up with a proper module system for roofing of dwelling houses, where the roofing is completed to meet the demands of the Scandinavian market. During the project a lot of effort has been put into customer contacts and the usability of the product, as well in the manufacturing process as on the construction site. This development has gone hand in hand with several practical tests and tryouts.

<- Föregående sida 5 Nästa sida ->