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352 Uppsatser om Organic hydroponic - Sida 20 av 24

Foderbetor och kogödsel som substrat för biogasproduktion; anaerob mesofil samrötning i labbskala

One of Sweden?s sixteen national environmental objectives strives to decrease the impact on the climate. By 2020, green house gas emissions should be 40 % less compared to the levels of 1990 and a minimum of 50 % of the energy consumption should come from renewable energy sources. Because of this there is a great need of increasing the production of renewable energy. This is where biogas comes in as a competitive alternative.

Family or State? Communitarian Perspectives on Economic Responsibility for Unemployed Youth

At the beginning of the 21st century, youth unemployment is paid attention to by the Swedish government and media. A grand part of the unemployed youth live at their parents´ house because of economic reasons contrary to their primary goal to be able to make their own living. It can be argued that the young unemployed´ s social citizenship is inferior to working citizens´ social citizenship. The thesis will not deal with suggestions on practical solutions, but rather seek for theoretical answers to whether the responsibility for the young people referred to should be a responsibility of the State or of the family. Communitarianism is a relatively young theory which is interesting for this thesis because it sheds light on the dichotomy individual - community.

LCA av dricksvattendesinfektion : en jämförelse av klor och UV-ljus

Disinfection methods for drinking-water produced at the two water works of Stockholm Water Co are compared in this study. Three different nethods are compared; disinfection with chlorine gas, disinfection with sodium hypochlorite and disinfection with UV-light and monochloramine. The method used is Life cycle assessment, LCA. LCA is defined as the compilation and evaluation of the inputs, outputs and potential environmental impact of a product system shroughout its life cycle. The environmental burden is compared for the three different disinfection methods.

Energieffektivisering av aerbo reningsprocess : Tillsats av biprodukter i skogsindustriellt avloppsvatten

In the production of pulp, paper and cardboard, a large amount of water is used daily. The water has to be purified in the internal purifying plant before it reaches the receiving body of water. In the biological purifying stage at the Stora Enso Skoghall mill, an aerated basin is used where the microorganisms, using oxygen, oxidize the organic material to carbon dioxide. The air is pumped from the bottom of the basin and the oxygen can then be transported from the air bubbles to the water through diffusion. The problem with aeration of waste water from the forest industry is that wood residues, such as fatty acids, are making the transport of oxygen in water more difficult.

Finns det rätta livsmedelsvalet?

Outdoor recreation habits in metropolis and rural areasThis study aims to examine the perception of nature and outdoor recreation habits from an urban-rural prospective. The urbanization process continues in Sweden and the populations of the cities are growing continuously. Trends to build more compact and ?climate smart? reigns and with this a risk that green areas and areas where outdoor recreation can be practiced are situated further and further away from the urban population. Analyzing the responses from a survey made by the research program Friluftsliv i förändring 2007 we have examined if and which differences exists between urban and rural areas regarding their perception of nature, outdoor recreation habits and factors influencing the practice of outdoor recreation.

Autumn water sources for understory vegetation and fungi in a boreal forest : an evaluation using stable isotopes

Understory vegetation and fungi are regarded as important ecological drivers of processes like productivity and nutrient cycling in boreal forests. Whilst those processes are linked to soil water content, relatively little is known about the sources of soil water for these forest components. During early autumn in boreal forests, temperature falls and large events of rain are frequent which may influence soil water availability. To better understand the autumn plant-soil-fungi water relationships in this ecosystem, I used stable isotopes techniques in this study to examine the water sources for ericaceous shrubs and fungi in a Scots pine forest following a large, early autumn rain event. I hypothesize that ericaceous shrubs of two functional groups (evergreen vs.

Frystorkning Kontrollerad torkning av kulturhistorisk dräkt?

Cultural objects may become wet by deliberate water cleaning, water disaster or watersoaked for other reasons. Air drying textile objects and even other organic materials from awater wet state, involves many problems depending on the strong capillarity action of water.Damages and changes such as bleeding of dyes, stains or lines of impurities from watermovement, shrinking or stiffness can occur. Freeze-drying as an alternative drying methodhas often been used for wet archaeological and marine objects, but more seldom for historicalmaterials.This bachelor thesis addresses the issue of whether freeze-drying can be an alternative controlleddrying method for historic costumes. Costumes and related objects are often compositeobjects, consisting of multiple materials, as well as being three dimensional, all of whichwill complicate drying. The purpose of this study was to investigate whether it is possible tohandle costume objects after wet cleaning for drying by freeze-drying, and if damages due tosurface tension of water, can be avoided in this way.

Surhetstillståndet i bäckar uppströmskalkdoserare i Dalarnas län

The acid deposition of sulphur- and nitrogenoxides from combustion of coal and oil cause acidification that lowers pH and gives increased contents of metals and altered aquatic biodiversity in the stream. The liming of lakes and streams, which was introduced to resist the acidification, demand large economic resourses despite of the decreased deposition of the acidifyng substances. Some of the streams are influenced by the acid deposition, while others are naturally acidic. It is therefore importaint to separate the anthropogenically acidified waters from the naturally acidic, in order to optimize the use of governmental fundings for liming. This thesis aims to estimate the acidity status and impact of acidification on 24 catchments upstream liming dispensers, which is part of the liming activities at the County of Dalarna.The acidity status of the streams was classified according to the Swedish Environmental Protection Agency old classification system (Naturvårdsverket 1999) as very acid to acid, with small ability to withstand a pH-change (alkalinity) due to acid deposition.

Migration och vegetationsupptag av radiocesium i åkermark - en långtidsserie av mätdata samt en långsiktig simuleringsmodell :

Abstract The accident in 1986 at the nuclear power station in Chernobyl, Ukraine, dispersed radioactive cesium over large areas of Europe. The half life of 137Cs is 30 years and this radionuclide also behaves like potassium, which means that it can easily be taken up by the vegetation or be adsorbed in to the structure of clays, principally illitic clays. When radiocesium decays ionizing radiation is emitted, which is harmful to humans that are exposed, either directly or indirectly through food intake. It is there-fore important to know what happens to the cesium that is dispersed into the environ-ment. In this project a simulation model was constructed to simulate the adsorption and transport of radiocesium in the soil and plant uptake.

Nedfästning av oljemåleri på puts.En fallstudie från salongen på Mostorps slott i Halland

This thesis, designed as a case study, is about complications concerning conservation of a decorative oil paint on lime plaster from the drawing-room in Mostorp castle sited in the county of Halland in south-west of Sweden. The building was built 1878-80 with an exterior of granite. The interior walls were made of clay bricks, lime mortar and lime plaster. The oil paint is applied to a layer of putty. The combination of different materials, which are organic and inorganic, affects the movement caused by internal and external stress.

ENERGIÅTERVINNING I GRANSHOT® - PROCESSEN

Uvån Hagfors Teknologi AB (UHT) has developed a process ? GRANSHOT® ? for quicksolidification of metals in water baths. In the process liquid metal is splintered ? granulated ?into small drops. The drops are rapidly cooled in a water bath where all the heat energy from theliquid metal is transferred into the water.

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.

Årstidsdynamik för kvicksilver i ett sövattensediment :

The limit for mercury in fish, set by health authorities, is exceeded in about half of the lakes in Sweden. Methyl mercury (MeHg) is the most toxic form of mercury and accumulates in fish. Therefore transformation of inorganic mercury (Hg) to methylmercury (MeHg) is an important process that we need to understand in order to possibly counteract the negative effects of mercury in the environment. The seasonal dynamics of mercury biogeochemistry is likely of great importance for the accumulation of MeHg in the aquatic food web. In thesis the chemical speciation and transformations of Hg and MeHg in bottom waters and sediments is followed in Ängessjön, a small lake located on the east coast in the middle of Sweden. The lake is not directly affected by any industrial pollution and concentrations of Hg in the sediment reflect the atmospheric deposition in this area, as well as processes taking place along the hydrological pathways from soil to lake. Samples from sediment, bottom- and streamwater were collected in average every second month during the period Feb.

Den offentliga arbetsförmedlingen : Vilka skillnader finns det mellan den offentliga arbetsförmedlingen och privata arbetsförmedlingar?

During half a century the society has been changed from an industrial to knowledge-driven society. Industry companies have standardized requirements and companies that works with development in production has unique qualifications. The public employment office was created during a time that each tailored to then general requirements were dominating and the adaptation average appropriate worker and appropriate work where general. When the monopoly was stopped, crew companies begun to settle down on the market that flexibly adapt themselves to carried out now specialized needs that require sophisticated adaptation average work and job seekers. Companies lose the confidence for the public employment office and politicians threaten the organization with big closure.

Rostfärgat slam i dränagesystem vid vattenkraftsanläggningar : orsaker och åtgärder

From embankment dams is something that has long been noticed and given rise to different questions. The most serious question is if the sludge is a result of inner erosion through the dam, and thus consists of material transported from the dam. Concerns have also been raised whether the sludge could interfere with the systems drainage capacity and thereby lead to high pore pressure in the dam, or if the measurement of seepage is disturbed, as the measuring is usually made via Thomson weirs, which could risk being blocked. The result of this investigation shows that the sludge is a result of the oxidation of iron by iron bacteria, and to the greater part consists of these oxides as well as the bacteria?s own structures. The iron oxidizing bacteria, FeOB, oxides ferrous iron to ferric as a part of their metabolism, and thereby create large quantities of iron(oxy)hydroxides.

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