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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
181

Emission av mikroplast vid hushållstvätt : En kritiskt granskning av nuvarande forskning inom mikroplastemission vid tvätt

Vu, Jennifer, Ekberg, Julia January 2020 (has links)
Den här studien är under projektet MinShed som drivs av RISE. MinShed är ett 3årigt projekt som undersöker mikroplastemission från syntetiska textilier vid tvätt. Den här studien har som syfte att genomföra en Critical Review på tidigare studier inom ämnet: Olika syntetiska material som släpper mikroplaster via hushållstvätt. Samtliga studier har sammanfattats i en framtagen matris där information om studiernas materialdata presenteras. Den främsta anledningen till varför en sådan matris ska presenteras är för att finna textilteknologiska gap som existerar i nuvarande forskning. Vad som omfattar textilteknologi kommer förklaringar ges mer ingående under litteraturgenomgången. I dagsläget finns det inte tillräckligt spårbara material för existerande forskning, därav är det svårt att avgöra exakt vilka textilparametrar som orsakar mer eller mindre emission vid tvätt. Därför kan företag heller inte prioritera smartare designval för att reducera mikroplastemission. Av de18 undersökta studierna var det enbart 2 av dessa som hade full kontroll överprovmaterialet. Detta betyder att ytterligare forskning inom området är aktuellt. Vad som kan hindra forskningen att utvecklas är förnärvarande textilbranschen. Det finns ingen trovärdig uppsikt över textilmaterial och dess processer, vilket försvårarutförandet att spåra de textilparametrar som orsakar emission vid tvätt. För att dra slutsatser mellan emission och konstruktionsparametrar för textil så bör man i framtiden tänka på att enbart testa en parameter åt gången. Utifrån resultatet från denna studie rekommenderas en egen tillverkning av materialet för att få en spårbartextilproduktion, då det ger ett mer trovärdigt resultat på grund av mer kontroll över processerna som textiler genomgår. / This study is performed under the project MinShed run by RISE. MinShed is a 3-year project that investigates in Microplastics emissions from synthetic textiles during domestic washing. The aim of the study is to do a Critical Review on previous research in the subject: Various synthetic materials that release microplastics during domestic laundry. The previous research is presented in a matrix, where information about the presented by the investigated laundry parameters, as well as the textile parameters. The main reason why such matrix is needed is to find the gap that contains the textile parameters for the various researches. Some of the most important textile parameters will be described during the literature review. At present, there is not enough traceable material for existing research, hence it is difficult to determine exactly which textile parameters which cause during washing. Therefore, companies cannot prioritize smarter design choices in order to reduce microplastics emissions from the materials. Of the 18research studies which were analyzed, only 2 of them had full control over their sample material. This means that further research in this area is needed. What can prevent future research is currently the textile industry. There is no reliable oversight of textile materials and their processes, which makes it difficult to track textile parameters that cause emission when washing. In order to be able to draw conclusions between emission and textile design parameters, researchers should remember to test only one parameter at a time and have an inhouse or own production of the specimens, this will give a better control of the results.
182

Advertising Skepticism : The influence of demographic factors, consumerism and green washing in the organic food industry

Van Kenhove, Nathalie, Biro, Lotti January 2016 (has links)
In 2016, it is no longer possible to deny the existence of global warming and its harmful effects on our planet and the environment. Not only experts, but also consumers, have become increasingly concerned about the environment. This increased awareness and concern has increased consumers’ interest in purchasing environmentally friendly food products, and has caused companies to focus on programs intent on reducing their environmental impact and helping the environment. Companies have introduced more environmentally friendly food products, accessible on a large scale, and have changed their communication to focus more on green products and green product attributes. Scandinavian countries have some of the largest numbers of organic food consumers in Europe and the world, with the Swedish organic food industry measuring the highest growth rate in organic food sales in 2015. Therefore, this study focuses on the Swedish green food industry. A major way for companies to make consumers aware of their available environmentally friendly food products is through green advertising. An increasingly frequent problem, however, is that consumers tend to distrust these green ads. They have knowledge of green washing practices and misleading information in green advertising. In this thesis, the relationships between green consumerism, green washing and green advertising skepticism were investigated. The potential relationship between demographic factors such as gender, age, income and level and area of study, and green advertising skepticism were tested as well. A research model with three main hypotheses was used in this thesis. The results showed a significant relationship between green consumerism and green advertising skepticism when green washing was a moderator. There was also a significant negative relationship between attitude towards green products and green advertising skepticism and a positive relationship between environmental concern and green advertising skepticism. There existed no significant relationship between the tested demographic factors and green advertising skepticism in the Swedish green food industry.
183

Integrated processes for removal of persistent organic pollutants : soil washing and electrochemical advanced oxidation processes combined to a possible biological post-treatment

Mousset, Emmanuel, Mousset, Emmanuel 02 December 2013 (has links) (PDF)
Soils contaminated by hydrophobic organic pollutants like polycyclic aromatic hydrocarbons (PAHs) are a common concern since they are extremely difficult to remove and their potential toxicological impacts are significant. As an alternative to traditional thermal or physical treatments, soil washing and soil flushing processes appear to be conceivable and efficient approaches, especially for higher level of pollution. However, the treatment of highly loaded soil washing/flushing solutions is another challenge to overcome. In that way, a new integrated approach is suggested: soil washing/flushing processes combined to an electrochemical advanced oxidation process (EAOP) in a combination with a recirculation loop (to save extracting agents) and/or a biological post-treatment step (to minimize energy cost).Extraction efficiency of the extracting agent like hydroxypropyl-beta-cyclodextrin (HPCD) is compared to the traditional non-ionic surfactant Tween 80 in synthetic and real soil washing solutions. A new simple fluorescent sensitive and selective quantification method is developed to monitor Tween 80 oxidation. Two EAOPs were compared: electro-Fenton (EF) and anodic oxidation (AO). Platinum (Pt) (in EF process) and boron doped diamond (BDD) (in both treatment) anodes are the respective electrodes employed to recycle effluents and to consider a biological post-treatment, respectively. Regarding the extracting agent recovery, the biodegradability evolution of effluent and the energy consumption (in kWh (kgTOC)-1) during EAOP, HPCD is more advantageous than Tween 80. However, in terms of extraction efficiency, costs of extracting agents and impact on soil respirometry, Tween 80 is much more efficient. By considering all these advantages and drawbacks, Tween 80 could still appear to be the best option
184

Razvoj modela praćenja procesnih parametara štampe tekstilnih materijala / Model for textile printing process parameters monitoring

Kašiković Nemanja 19 May 2012 (has links)
<p>U disertaciji je prikazan postupak razvoja modela praćenja procesnih parametara štampe tekstilnih materijala koji za rezultat ima kvalitetnu i postojanu štampu sa upravljivim i predvidivim procesom. U radu su date osnove praćenja procesnih parametara štampe tekstilnih materijala. Pratio se uticaj povećanja broja nanosa boje na različitim tekstilnim materijalima, i njihov uticaj na otpornost odštampanih uzoraka na svetlost, pranje, toplotno dejstvo i trljanje što je osnova razvoja modela disertacije.</p> / <p>The dissertation presents development of the process parameters monitoring model for textile printing which provides high-quality and consistent printing with controllable and predictable process parameters. The thesis provides the basis for monitoring of textile printing process parameters such as influence of number of ink layers printed on light fastness, washing fastness, scrubbing and thermal treatment various textile materials.</p>
185

Détermination du béryllium dans les cheveux humains non exposés, les poils et les os de souris exposées à des poussières de béryllium

Drolet-Vives, Katherine January 2009 (has links)
Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal.
186

Středověká a raně novověká exploatace zlata na Vodňansku. Studium opomíjené součásti historické sídelní infrastruktury a ekonomiky regionu / Medieval and Early Modern Age exploitation of gold in Vodňany. Study of neglected parts of historical residential infrastructure and economy of the region.

MAŠLOVÁ, Kateřina January 2017 (has links)
This diploma thesis presents the results of the study of historical exploitation of gold in Vodňany, which were partly introduced in previous bachelor thesis. The core of the thesis is a list of locations that have been researched mainly through studying lidar pictures, field and heavy minerals prospecting, professional literature and geological maps. Based on the observation of common or different features of the individual areals, the thesis further solved questions related to the morphology of the areals, the probable occurrence of gold, the method of its mining, and, consequently, property and settlement links.
187

Diversidade de fungos do solo da Mata Atlântica / Soil fungi diversity in the Atlantic Forest

Carvalho, Vivian Gonçalves 12 March 2012 (has links)
A Mata Atlântica é reconhecida como área de prioridade de conservação na América do Sul, devido ao grande número de espécies endêmicas e constantes ameças à sua biodiversidade em decorrência da substituição da vegetação natural. Embora várias informações sobre a diversidade vegetal e animal estejam disponíveis, pouco se sabe sobre a diversidade de microorganismos existentes no solo desse bioma. A diversidade de fungos do solo foi avaliada em três unidades de conservação da Mata Atlântica do estado de São Paulo: Parque Estadual de Carlos Botelho (PECB), Estação Ecológica de Assis (EEA) e Parque Estadual da Ilha do Cardoso (PEIC). Ao todo, foram analisadas 90 amostras de solo, coletadas em épocas de alta e baixa pluviosidade, e sob a copa de três espécies arbóreas: Cabralea canjerana, Guapira opposita e Maytenus robusta. Foram utilizados métodos independentes (PCR-DGGE e pirosequenciamento) e um método dependente do cultivo (lavagem de solo e filtração de partículas) para a análise da diversidade e estrutura das comunidades de fungos do solo. Os resultados obtidos foram analisados conjuntamente com os dados de atributos químicos do solo e frações da matéria orgânica do solo a fim de verificar suas possíveis relações com as comunidades de fungos. Os resultados obtidos sugerem uma grande diversidade de fungos no solo da Mata Atlântica. Através do método de cultivo, um total de 142 espécies de fungos foi identificado nas três áreas, sendo que a estrutura das comunidades de fungos não foi influenciada pelas espécies arbóreas, mas sim pelas áreas e épocas de amostragem. As comunidades de fungos cultiváveis do PECB e do PEIC foram mais similares entre si do que em relação às comunidades de fungos do solo da EEA, assim como os valores dos atributos químicos do solo dessas áreas foram mais semelhantes entre si. Pelo método de PCR-DGGE, as estruturas das comunidades de fungos das três áreas sofreram influência das espécies arbóreas sob a copas das quais as amostras foram coletadas. Somente a estrutura das comunidades de fungos no solo do PEIC não sofreu influência da época de amostragem. Usando pirosequenciamento, foram obtidas 39.152 sequências da região ITS de fungos, as quais foram agrupadas em 1.800 Unidades Taxonômicas Operacionais (UTOs). A diversidade de fungos na EEA e no PEIC variou em função das espécies arbóreas e épocas de coleta. A análise de NMS de cada área amostrada indicou que as comunidades de fungos do solo são muito homogêneas. O filo Ascomycota foi mais frequentemente detectado, tanto usando metodologia dependente quanto independente de cultivo. De maneira geral, as comunidades de fungos cultiváveis apresentaram maior relação com atributos químicos do solo, áreas e épocas de coleta, e as comunidades de fungos acessadas por PCRDGGE mostraram maior relação com as épocas de coleta e espécies arbóreas sob as quais as amostras de solo foram coletadas. A análise dos metadados usando rede neural revelou uma dependência da diversidade de fungos em relação às concentrações de ácidos húmicos, ácidos fúlvicos e humina no solo, além do pH e concentração de matéria orgânica total. / Brazilian Atlantic Forest is recognized as a top priority for conservation in South America because of its large number of innate species and the threats for the biodiversity due to vegetation changes. Although a plethora of data on plant and animal diversity in the Atlantic Forest is available, the diversity of soil microorganisms in this biome is still mostly unknown. Therefore, soil fungi diversity was evaluated in three Atlantic Forest conservation areas of São Paulo state: Estação Ecológica de Assis (EEA), Parque Estadual de Carlos Botelho (PECB) and Parque Estadual da Ilha do Cardoso (PEIC). A total of 90 soil samples were analyzed, collected in two different seasons (high and low precipitation seasons), and under the canopy projection of three tree species: Cabralea canjerana, Guapira opposita and Maytenus robusta. Two independent cultivation methods (PCR-DGGE and pyrosequencing) and one dependent method (soil washing and particles filtration method) were used for the analysis of soil fungi diversity and community structure. The results of these methods were analyzed together with the data on soil chemical attributes and organic matter fractions in the same samples, in order to verify the possible relations with soil fungi communities. The results suggest a great diversity of soil fungi in the Atlantic Forest. Through the cultivation method, a total of 142 fungi species were identified for the three areas. The structure of fungi communities was not affected by the tree species, but were affected by the sampling areas and seasons. Cultivable fungi community in PECB and PEIC were more similar to each other than in EEAs soil fungi community. In addition, the values of the chemical properties of these areas were more similar to each other. The structure of soil fungi community accessed by PCR-DGGE showed that the three areas were influenced by the tree species under the canopy where the soil samples were collected. Only the structure of PEICs fungi communities was not influenced by the season. By means of pyrosequencing, 39,152 sequences were retained from the ITS rDNA region, which were clustered in 1,800 Operational Taxonomic Unities (OTUs). Fungal diversity in EEA and PECB areas was influenced by the tree species and seasons. NMS analysis of each sampled area showed that soil fungi communities are very homogenous. Ascomycota was the most frequent phylum detected by both dependent and independent cultivation methods. Overall, the communities of cultivable fungi were more related to soil chemical attributes, sampling areas and seasons. Fungal communities accessed by PCR-DGGE showed greater relation with the seasons and tree species where the soil samples were collected. Analysis of metadata using neural network revealed fungal diversity dependence of humic acids, fulvic acids and humin concentrations in soil, as well as pH and organic matter concentrations.
188

Diversidade de fungos do solo da Mata Atlântica / Soil fungi diversity in the Atlantic Forest

Vivian Gonçalves Carvalho 12 March 2012 (has links)
A Mata Atlântica é reconhecida como área de prioridade de conservação na América do Sul, devido ao grande número de espécies endêmicas e constantes ameças à sua biodiversidade em decorrência da substituição da vegetação natural. Embora várias informações sobre a diversidade vegetal e animal estejam disponíveis, pouco se sabe sobre a diversidade de microorganismos existentes no solo desse bioma. A diversidade de fungos do solo foi avaliada em três unidades de conservação da Mata Atlântica do estado de São Paulo: Parque Estadual de Carlos Botelho (PECB), Estação Ecológica de Assis (EEA) e Parque Estadual da Ilha do Cardoso (PEIC). Ao todo, foram analisadas 90 amostras de solo, coletadas em épocas de alta e baixa pluviosidade, e sob a copa de três espécies arbóreas: Cabralea canjerana, Guapira opposita e Maytenus robusta. Foram utilizados métodos independentes (PCR-DGGE e pirosequenciamento) e um método dependente do cultivo (lavagem de solo e filtração de partículas) para a análise da diversidade e estrutura das comunidades de fungos do solo. Os resultados obtidos foram analisados conjuntamente com os dados de atributos químicos do solo e frações da matéria orgânica do solo a fim de verificar suas possíveis relações com as comunidades de fungos. Os resultados obtidos sugerem uma grande diversidade de fungos no solo da Mata Atlântica. Através do método de cultivo, um total de 142 espécies de fungos foi identificado nas três áreas, sendo que a estrutura das comunidades de fungos não foi influenciada pelas espécies arbóreas, mas sim pelas áreas e épocas de amostragem. As comunidades de fungos cultiváveis do PECB e do PEIC foram mais similares entre si do que em relação às comunidades de fungos do solo da EEA, assim como os valores dos atributos químicos do solo dessas áreas foram mais semelhantes entre si. Pelo método de PCR-DGGE, as estruturas das comunidades de fungos das três áreas sofreram influência das espécies arbóreas sob a copas das quais as amostras foram coletadas. Somente a estrutura das comunidades de fungos no solo do PEIC não sofreu influência da época de amostragem. Usando pirosequenciamento, foram obtidas 39.152 sequências da região ITS de fungos, as quais foram agrupadas em 1.800 Unidades Taxonômicas Operacionais (UTOs). A diversidade de fungos na EEA e no PEIC variou em função das espécies arbóreas e épocas de coleta. A análise de NMS de cada área amostrada indicou que as comunidades de fungos do solo são muito homogêneas. O filo Ascomycota foi mais frequentemente detectado, tanto usando metodologia dependente quanto independente de cultivo. De maneira geral, as comunidades de fungos cultiváveis apresentaram maior relação com atributos químicos do solo, áreas e épocas de coleta, e as comunidades de fungos acessadas por PCRDGGE mostraram maior relação com as épocas de coleta e espécies arbóreas sob as quais as amostras de solo foram coletadas. A análise dos metadados usando rede neural revelou uma dependência da diversidade de fungos em relação às concentrações de ácidos húmicos, ácidos fúlvicos e humina no solo, além do pH e concentração de matéria orgânica total. / Brazilian Atlantic Forest is recognized as a top priority for conservation in South America because of its large number of innate species and the threats for the biodiversity due to vegetation changes. Although a plethora of data on plant and animal diversity in the Atlantic Forest is available, the diversity of soil microorganisms in this biome is still mostly unknown. Therefore, soil fungi diversity was evaluated in three Atlantic Forest conservation areas of São Paulo state: Estação Ecológica de Assis (EEA), Parque Estadual de Carlos Botelho (PECB) and Parque Estadual da Ilha do Cardoso (PEIC). A total of 90 soil samples were analyzed, collected in two different seasons (high and low precipitation seasons), and under the canopy projection of three tree species: Cabralea canjerana, Guapira opposita and Maytenus robusta. Two independent cultivation methods (PCR-DGGE and pyrosequencing) and one dependent method (soil washing and particles filtration method) were used for the analysis of soil fungi diversity and community structure. The results of these methods were analyzed together with the data on soil chemical attributes and organic matter fractions in the same samples, in order to verify the possible relations with soil fungi communities. The results suggest a great diversity of soil fungi in the Atlantic Forest. Through the cultivation method, a total of 142 fungi species were identified for the three areas. The structure of fungi communities was not affected by the tree species, but were affected by the sampling areas and seasons. Cultivable fungi community in PECB and PEIC were more similar to each other than in EEAs soil fungi community. In addition, the values of the chemical properties of these areas were more similar to each other. The structure of soil fungi community accessed by PCR-DGGE showed that the three areas were influenced by the tree species under the canopy where the soil samples were collected. Only the structure of PEICs fungi communities was not influenced by the season. By means of pyrosequencing, 39,152 sequences were retained from the ITS rDNA region, which were clustered in 1,800 Operational Taxonomic Unities (OTUs). Fungal diversity in EEA and PECB areas was influenced by the tree species and seasons. NMS analysis of each sampled area showed that soil fungi communities are very homogenous. Ascomycota was the most frequent phylum detected by both dependent and independent cultivation methods. Overall, the communities of cultivable fungi were more related to soil chemical attributes, sampling areas and seasons. Fungal communities accessed by PCR-DGGE showed greater relation with the seasons and tree species where the soil samples were collected. Analysis of metadata using neural network revealed fungal diversity dependence of humic acids, fulvic acids and humin concentrations in soil, as well as pH and organic matter concentrations.
189

A study of the importance of various elements of the marketing-mix in the purchase of laundry detergent powder.

January 1990 (has links)
by Monica Cheung Wai, Eppie Wong Yuen Yee. / Thesis (M.B.A.)--Chinese University of Hong Kong, 1990. / Bibliography: leaf 65. / ABSTRACT --- p.ii / TABLE OF CONTENTS --- p.iii / ACKNOWLEDEGMENTS --- p.v / Chapter I. --- INTRODUCTION --- p.1 / Chapter II. --- STUDY OF THE PURCHASE OF DETERGENT POWDER / Chapter 2.1 --- Market Situation for Detergent Powderin Hong Kong --- p.3 / Chapter 2.2 --- Rationale of the Study --- p.4 / Chapter 2.3 --- Scope of the Study --- p.5 / Chapter 2 .4 --- Objectives of the Study --- p.6 / Chapter III. --- LITERATURE REVIEW / Chapter 3.1 --- Relevance of Understanding Consumer Purchase Behaviour in the Marketing Concept --- p.8 / Chapter 3.2 --- Howard Model of Consumer Behaviour --- p.8 / Chapter 3.3 --- "Engel, Kollat and Blackwell Model" --- p.9 / Chapter 3.4 --- Definition of Detergent Powder Purchase --- p.10 / Chapter 3.5 --- Research Findings : Hoyer --- p.11 / Chapter 3.6 --- Choice Tactics in Detergent Powder Purchase --- p.13 / Chapter 3.7 --- Product Information in Memory --- p.16 / Chapter 3.8 --- Applicability of Hoyer's Research Findings --- p.17 / Chapter 3.9 --- Relevance of Judgmental Models in Detergent Powder Purchase --- p.17 / Chapter IV. --- METHODOLOGY AND FRAMEWORK FOR ATTACK / Chapter 4.1 --- The Pilot Study --- p.21 / Chapter 4.2 --- The Observation Phase --- p.22 / Chapter 4.3 --- The Questionnaire Survey --- p.23 / Chapter V. --- SUMMARY OF RESEARCH FINDINGS / Chapter 5.1 --- Observation Survey --- p.27 / Chapter 5.2 --- Salience of Various Evaluative Criteria --- p.28 / Chapter 5.3 --- Propensity for Brand Switching --- p.29 / Chapter 5.4 --- Consumers' Evaluation of the Product Attributes of their Current Brand --- p.32 / Chapter 5 .5 --- Attitude --- p.34 / Chapter 5.6 --- Difference in Purchase Behaviour among Consumers across Demographic Profiles --- p.35 / Chapter 5.7 --- Demographic Profile of the Sample --- p.38 / Chapter VI. --- DISCUSSION AND IMPLICATIONS / Chapter 6.1 --- Decision Process Behaviour and Advertising Strategy --- p.43 / Chapter 6.2 --- Brand Switching Behaviour and Promotional Strategy --- p.45 / Chapter 6.3 --- Satisfaction with Current Brand and Relevance of Promotional Efforts --- p.46 / Chapter 6.4 --- Salience of Evaluative Criteria -- Pricing and Product --- p.47 / Chapter 6.5 --- Purchase Behaviour among Consumers across Demographic Profiles -- and its Marketing Implications --- p.48 / Chapter 6.6 --- Limitations of the Study and Suggestions for Further Research --- p.49 / APPENDICES / Chapter Appendix A: --- Observation Sheet --- p.51 / Chapter Appendix B: --- Schedule of Questionnaire Survey --- p.52 / Chapter Appendix C: --- The Questionnaire (English and Chinese versions) --- p.53 / Chapter Appendix D: --- Research Data --- p.58 / Chapter Appendix E: --- T-test Table- --- p.61 / Chapter Appendix F: --- F-test Table --- p.63 / BIBLIOGRAPHY --- p.65
190

Faktorer för effektiv infiltration av dagvatten hos permeabel asfalt / Factors for effective infiltration of storm water in permeable asphalt

Hedlöf Ekvall, Linnea January 2019 (has links)
För att permeabel asfalt skall vara ett bra sätt att ta hand om dagvatten i en stad med allt fler hårdgjorda ytor är det viktigt att den långsiktigt kan infiltrera dagvatten. Då det inte går att undvika att permeabel asfalt utsätts för små partiklar finns det en risk för att den skall sätta igen och förlora sin förmåga att infiltrera dagvatten. Som en skötselåtgärd för att förhindra att den sätter igen kan rengöring med högtryckstvätt och vakuumsugning göras. I detta examensarbete undersöktes det vilken effekt rengöring med högtryckstvätt och vakuumsugning har på permeabel asfalts infiltrationskapacitet. Vidare undersöktes även vilken typ av uppbyggnad av den permeabla asfalten som var mest lämplig för en effektiv infiltration. Litteraturstudie och intervjuer om permeabel asfalt samt infiltrationsförsök har utförts. För att uppbyggnaden av permeabel asfalt hydrologiskt sett skall fungera på ett bra sätt framkom det, i litteraturstudier och intervjuer, att det är viktigt att alla lager i uppbyggnaden verkligen är permeabla och att uppbyggnaden bör anpassas efter rådande förhållanden på anläggningsplatsen. Förhållanden som till exempel bör tas hänsyn till är underliggande jordart och närheten till grundvattenyta. I litteraturstudier och intervjuer framkom det att regelbunden skötsel av den permeabla asfalten är mycket viktig för dess långtidsfunktion att kunna infiltrera dagvatten. Infiltrationsförsöken skedde på två platser med permeabel asfalt i Uppsala; på en parkering vid ett köpcentrum i Gnista och på en lokalgata i Gränby backe. Infiltrationskapaciteten uppmättes innan och efter rengöring med högtryckstvätt och vakuumsugning på den permeabla asfalten. Vid Gnista kunde ingen infiltration uppmätas varken före eller efter rengöring. I Gränby backe ökade infiltrationskapaciteten från 0,47–0,71 mm/min till 1,24–12,23 mm/min efter rengöring. Denna infiltrationskapacitet visar på att den permeabla asfalten i Gränby backe kunde infiltrera dimensionerade regn med allt från 7 års återkomsttid till över 1000 års återkomsttid och med 10 minuters varaktighet. Det framkom i litteraturstudien att högtryckstvätt och vakuumsugning i olika studier har haft en positiv effekt på att upprätthålla och till viss del återskapa infiltrationskapaciteten hos permeabel asfalt. Vid infiltrationsförsöken i detta examensarbete påvisades även en positiv effekt, till viss del, av denna rengöringsmetod på infiltrationskapaciteten. Utifrån detta skulle rengöring med högtryckstvätt och vakuumsugning kunna rekommenderas som skötselmetod på permeabel asfalt.  Resultaten i Gnista skiljde sig från de i Gränby backe då det i Gnista varken före eller efter rengöring fanns någon infiltrationskapacitet. Det skiljer sig endast ett år i ålder mellan de båda försöksplatserna, de har skötts på liknande sätt sedan anläggning och litteratur visar på att rengöring med högtryckstvätt och vakuumsugning skall ha en effekt på infiltrationskapaciteten. Detta kan tyda på att bristen på infiltrationsförmåga i Gnista kan bero på något annat än igensättning av den permeabla asfalten. / It is important that permeable asphalt is able to infiltrate storm water in the long-term for it to be a viable alternative for handling storm water. Permeable asphalt will always, in some way, be exposed to fine particles and therefore there is a risk that clogging will occur and that the permeable asphalt will lose its ability to infiltrate storm water. As a mean of maintenance cleaning with high pressure washing and vacuum cleaning can be done to prevent clogging. In this master thesis the effect of high pressure washing and vacuum cleaning on the infiltration capacity of permeable asphalt was examined.  Also, the most suitable type of substructure for effective infiltration was examined. A literature study and interviews were conducted in combination with infiltration experiments on two locations with permeable asphalt in Uppsala. Literature studies and interviews state that for the substructure to be hydrologically well functioning it is important that every layer in the substructure really is permeable. The substructure should also be adapted to the conditions at the site where it is built. For example, conditions to take into consideration are soil type and highest level of groundwater. All through literature and interviews regular maintenance is said to be very important for the long-term functioning and infiltration of permeable asphalt. The infiltration experiments were conducted at a parking lot at a shopping center in Gnista and a small local street in Gränby backe. The infiltration capacity of the permeable asphalt was measured before and after maintenance with high pressure washing and vacuum suction. No infiltration capacity could be measured before or after maintenance at Gnista. In Gränby backe the infiltration capacity was 0,47-0,71 mm/min before maintenance and 1,24-12,23 mm/min after. According to this infiltration capacity the permeable asphalt in Gränby backe can infiltrate design rains with return periods of 7 years to over 1000 years and with a duration of 10 minutes. In research, high pressure washing, and vacuum suction were found to be able to maintain, and in some cases restore, infiltration capacity. In this master thesis’ infiltration experiments a positive effect on infiltration capacity by cleaning with high pressure washing and vacuum suction was partially found. According to this high pressure washing and vacuum suction can be recommended as a maintenance method on permeable pavement. The results from the two experiment sites stood apart from each other as Gnista had no infiltration capacity neither before nor after cleaning. In age, the two sites only differ by one year, and since they were built they have received similar maintenance and literature shows that high pressure washing and vacuums suction have an effect on infiltration capacity. This might indicate that the lack of infiltration capacity at Gnista might be due to something else than clogging.

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