Sökresultat:
653 Uppsatser om Chemical composition - Sida 41 av 44
Modellering av organiskt material i avloppsvatten vid mekanisk tillverkning av pappersmassa : Regressionsanalys baserad på COD- och TOC-analyser vid olika grader av blekning och raffinering
I avloppsreningen på Hallsta pappersbruk i Hallstavik reduceras dagligen tonvis med organiskt material innan avloppsvattnet släpps ut i den intilliggande Edeboviken. Bruket är ett så kallat integrerat pappersbruk vilket innebär att man tillverkar både pappersmassan och pappret på plats. Det är främst vid framställningen av massa som det organiska materialet löses ut ur veden och hamnar i processvattnet som så småningom når brukets avloppsreningsverk. På bruket tillverkas papper i olika ljusheter, vilket kräver olika stora insatser i form av blekkemikalier så som väteperoxid och hydrosulfit (även känt som ditionit). Blekningen varierar över tid i produktionscykler och det är sedan tidigare känt att en ökad blekning av massan löser ut mer organiska föreningar.
Miljöanpassad offentlig upphandling: effektivt styrmedel mot koldioxidutsläpp? : En studie av kostnadseffektivitet, transaktionskostnader och teknisk utveckling
Green public procurement (GPP) can be used as an instrument to reduce carbon dioxide emissions, and consideration of environmental aspects within public procurement is becoming more common in Sweden and internationally. Two product groups that have been pointed out as especially important are transports and electricity, where the opportunities for public purchasers to reduce emissions are relatively large. This paper studies GPP which aims at reducing emissions, primarily of carbon dioxide, through environmental requirements within these two product groups. A theoretical analysis of cost-effectiveness, transaction costs and effects on technological development is performed, followed by a closer study of how these aspects appear in practice within GPP.
The results indicate that a cost-effective allocation of reductions between the two product groups is most likely to be attained if the main part of emission reduction is achieved through environmental requirements on electricity. The cost for emission reduction within transports is relatively high, especially for heavy transports.
For transportation services, more generally focused requirements on emission reductions could probably give greater environmental gains, but the existence of transaction costs steer the environmental requirements towards more technology specific types.
Retention of stumps on wet ground at stump-harvest and its effects on saproxylic insects
Low stumps represent on their own up to 80% of the dead wood remaining on clear cuts and therefore supply suitable habitat for saproxylic insects i.e. insects depending on dead wood for their survival. Recent stump harvesting activities threaten this substrate of ecological importance and increase the anthropogenic negative impacts on these species. Because of technical and environmental reasons (nutrient leakage, erosion) guidelines for stump harvesting recommend to retain stumps standing in wet parts of clear cuts. However, stumps in wet positions might not be a satisfactory substrate for saproxylic insects and therefore might not be as much used as stumps in dry positions.
Minskande andelar kraftfoder i foderstaten under betesperioden : effekt på mjölkavkastning och betesbeteende hos mjölkkor
Feed costs constitute a large part of the expenses of dairy farmers. Pasture is a high quality feed with a low cost. However, feeding with concentrates has been shown to enhance milk yield (Leaver, 1985; Bargo et al., 2003; Stockdale, 2004). The purpose with this study was to investigate how milk yield and milk composition were affected as the concentrate proportion in the diet decreased. Pasture behaviour was examined to see if the different concentrate levels affected the time cows spent grazing and ruminating.
The major food trees of the Angola black-andwhitecolobus (Colobus angolensis palliatus)in Diani Forest, Kenya
The Angola black-and-white colobus (Colobus angolensis palliatus) is a subspecies of Colobus angolensis inhabiting fragmented forests in coastal Kenya and Tanzania. C. angolensis is regarded as Least Concern in the red list of IUCN because its populations are abundant. However, the populations of C. a.
Use of oxytocin to improve diagnosis of subclinical mastitis caused by Staphylococcus aureus
Mastitis, inflammation in the udder tissue, caused by S. aureus is a big problem in dairy cattle production. It causes suffering for the cow and curing or replacing the infected cow is costly for the farmer. It is known that beef cattle also suffer from mastitis caused by S. aureus.
Kokvigeproduktion baserad på köttraser : en fältstudie
Most of the beef production in Sweden has been integrated with milk production. Since the 1990:s, the number of dairy cows has decreased. A specialised beef production has developed in purpose to compensate for this decrease. The consumption of beef have increased in the last decade, but the Swedish production has no followed this trend. In 2004, the percentage of beef self-sufficiency in Sweden was 60 %.
Konsten att lyckas med förankring
The purpose of this thesis work is to formulate a model with methods that describe key success factors to get understanding and awareness in organizational change projects. We have used a project within the township of Gothenburg as a case and connected to this single project the purpose is to identify key success factors to get understanding and awareness among employees within the township of Gothenburg. We hope that our result will be useful in other large organizational change projects. Theoretic basis for our study have been models and methods, while our purpose have been to construct a model with suitable methods for anchoring. Theories about coaching and process management are examples of methods to get understanding and awareness among employees in change projects.
Flygbildsanalys av trädskiktets status efter brand : en metodstudie
During the past years fire has been identified as an important factor for nature conservation in the forest landscape. To accurately quantify the size of a burnt area is obviously important, but also to quantify the degree of fire damage to the tree canopy. Such data are important for assessing the conservation value, and to support planning and management of the burned area in the future.
I have examined how to estimate the status of tree crowns after fire from interpretation of aerial photographs. This is possible because fire changes the structure of tree crowns and this influences the colours in aerial photographs by spectral reflection.
Included in the study are four areas, three of which burned in 2005 and one in 2006.
Effekten av mjölkkors rang på ?antistresshormonet? oxytocin, mjölkavkastning, mjölkflöden och besökstider i mjölkningsenheten i ett automatiskt mjölkningssystem :
The study was carried out at the Kungsängen Research Centre, Department of Animal Nutrition and Management, Swedish University of Agriculture Sciences, Uppsala.
The technical development in dairy production has resulted in a housing system where feeding and milking is done automatically without human contact, a so called automatic milking system. The motives for utilising an automatic milking system, is to increase the animal welfare and to decrease the need for manual labour. However, the system does involve a change for the animals, among the effects is the deprival or the diminishment of a chance for synchronous behaviour and the animals have to agree among themselves in which order they use the feeding stations and the milking unit itself. How and if this affects the animals well-being and production is yet to be solved. A possible way to form an opinion on this, is to study the animals ranking order along with hormone profiles and production.
The purpose of this work was to study the effect of low- vs.
Lärares bedömning av bildämnet vid en lärarutbildning i Sydafrika : En minor Field study
Bedömning av estetiska ämnen har varit ifrågasatt gällande dess kvalité, rättvisa, funktion och hur det påverkar ämnet och individen. Studien syftar till att beskriva bedömning av det estetiska ämnet Visual Arts vid en lärarutbildning i Sydafrika presenterat ur ett lärarperspektiv. Forskningsfrågorna utgår från ämnesdidaktikens teori gällande Vad bedöms, Hur kommuniseras bedömningen och Varför görs bedömningen. Metoden som använts är ett två månaders fältarbete vid en bildlärarutbildning där jag följt tre lärare och deras arbete genom deltagande observation, samtal, intervjuer och insamling av vissa dokument.Det empiriska materialet har analyserat från de tre didaktiska frågorna. Resultatet visar att lärarna, som var utbildade konstnärer lade ned mycket tid och engagemang på bedömning.
Kan nutritionsbehandling bidra till läk-ning av trycksår bland äldre patienter?
Sahlgrenska Academyat University of GothenburgDepartment of Internal Medicine and Clinical NutritionTitle: Can nutritional support contribute to the healing of pressure ulcers in elderly patients?Author: Anton Kinnander, Sandra SmidelikSupervisor: Elisabet RothenbergExaminer: Anna WinkvistProgramme: Dietician study programme, 180/240 ECTSType of paper: Examination paper, 15 hpDate: 12-04-11Background The number of elderly patients with co-morbidity is increasing in the western world. It is therefore reasonable to predict increasing incidence and prevalence of pressure ulcers. One study, published 2009, found that as many as 59 % of geriatric patients within the Swedish health care system had developed pressure ulcers. Symptoms vary from mild erythema to severe deep tissue damage and development of pressure varies from hours to weeks.
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.
Klövviltets besöksfrekvens och bete i sydsvenska poppelplanteringar
Energy is an essential part of the society and for a sustainable future we need to use the energy resources in a sustainable way. The forest is Sweden?s most important resource for renewable energy and a higher production combined with shorter rotation periods (time from planting to clear cutting) can increase the access to energy. The tree genus poplar (Populus spp.) is interesting as energy resource as it has both high production and short rotation period.
But browsing ungulates are a major threat to the establishment of poplar plants and therefore the poplar plantations need to be fenced in today. To use fences is expensive and time consuming; this makes it interesting to find more cost-effective solutions where there is no need to fence.
The aim with this study was to look at the ungulates? occupation rate and browsing pressure in poplar plantations without fence.
Grupper vs. Individer : en kvantitativ studie om gruppers risktolerans i förhållande till individers
Beslut angående finansiella investeringar sker för den enskilde individen likaväl som i företag. Besluten följer den finansiella världens utveckling och blir därmed alltmer komplexa. Placeringar av monetära tillgångar med förväntan att generera inkomst eller värdestegring innebär en risk. Risknivån på investeringen beror på investeringsbeteendet hos beslutsfattaren som kan ge konsekvenser på den finansiella marknaden och kan så småningom leda till finanskriser om ett överdrivet behov av risk uppstår hos beslutsfattare.Genom att studera vad som påverkar risktolerans öppnas dörrar för att kunna förstå vad som ligger bakom vilken risk som väljs vid en finansiell investering. När förändring i risktolerans studeras tas hänsyn till vilka sorters beslutsfattare som finns på den finansiella marknaden.