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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.
1

Měření a analýza usazování vláken z izolační minerální vaty v dýchacím systému / Measurement and analysis of deposition of fibers from mineral wool in respiratory system

Hájek, Ondřej January 2020 (has links)
This master thesis deals with inhalation of fine particles and fibres into human lungs. This is a scientific field where computer modelling is used to describe the movement of fibres and their deposition in the lungs. However, the results of these simulations must be verified experimentally. The prediction of fibres behaviour is important from a toxicology point of view where it is important to know deposition hot-spots and places where fibres could possibly cause problems. The review of the state-of-the-art is focused on the deposition of particles in human lungs followed with a chapter on fibre as a type of particle, and occupational exposure limits set by different world associations. The last theoretical chapter describes human lungs and its diseases which can evolve when limits for occupational exposure are not met. The experimental chapter consists of a description of the used experimental setup and results from an experiment together with a comparison of results with other similar experiments.
2

Återvinning av glasull : Mot en mer hållbar utveckling / Glas wool recycling : Towards a more sustainable development

Marija, Milacic, Johanna, Persson January 2023 (has links)
Studiens syfte undersökte återvinningsproblematiken kring materialet glasull och varför glasull i hög grad hamnar på deponi. Studien är utförd som en kvalitativ studie med semistrukturerade intervjuer för att få mer detaljerade svar och mer kunskap om glasull från organisationer som arbetar med materialet. Teorierna som har använts i studien är institutionell teori och cirkulär ekonomi. Resultaten visade att det krävs mer samarbete och kommunikation mellan tillverkare, användare, och avfallsstation för att hitta lösningar som möjliggör återvinning. Det framkom även att sortering och separering av material på rivningsplatsen har en stor betydelse för återvinning av glasull, eftersom det skapar möjlighet för en ökad cirkularitet. Vidare visade resultatet glasullavfallets låga värde vilket leder till mindre motivation att återvinna materialet.   Studiens slutsats är att d​​et som görs idag inte är tillräckligt för att nå en mer hållbar utveckling, inte ens för att minimera glasull på deponin.  “Vi har bara en planet och det är ett gemensamt ansvar”. / The purpose of the study was to investigate the recycling problems associated with the material glass wool and why glass wool largely ends up in landfill. The study is conducted as a qualitative study with semi-structured interviews to get more detailed answers and more knowledge about glass wool from the organizations that work with the material. The theories that have been used in the study are institutional theory and circular economy. The results showed that more cooperation and communication between manufacturers, users, and waste stations is needed to find solutions that enable recycling. It also emerged that sorting and separating materials at the demolition site is of great importance for glass wool recycling, as it creates the opportunity for increased circularity. Furthermore, the result showed the low value of glass wool waste, which leads to less motivation to recycle the material.   The conclusion of the study is that what is being done today is not enough to achieve a more sustainable development, not even to minimize glass wool in the landfill.  "We only have one planet and it is a shared responsibility".
3

Optimierung der Glaswollefiltration von menschlichen Ejakulaten zum Zwecke der assistierten Reproduktion für labordiagnostische Untersuchungen

Weber, Holm 01 April 1999 (has links)
Mittels Glaswolle (Microfibre code 112) in einer speziellen Filtrations-Anordnung steht ein effektives Spermienpräparationsverfahren zur Verfügung. Durch Ausnutzung eines gefäßforminduzierten Konzentrierungseffektes kann auf samenzellschädigende Zentrifugation zur Spermatozoen-Anreicherung verzichtet werden. Folgend aufgeführte Ergebnisse sind Mittelwerte aus 30 Messungen. Die Computer-Assistierte Spermienmotilitäts-Analyse (CASA) zeigt eine gegenüber dem nativen Ejakulat signifikante Erhöhung der Spermienkonzentration im Filtrat (27,45 vs. 69,56 Mio/ml). Das Verteilungsverhältnis der Samenzell-Populationen nach Glaswolle- Filtration bietet gute Voraussetzungen für assistierte Reproduktion. Unter Abnahme des immotilen Anteils auf 1/5 (54,53 vs. 11,66 %), erhöht sich konsekutiv der motile Spermien-Anteil (39,53 vs. 82,06 %). In der weiteren Spezifisierung motiler Spermatozoen, kann eine Verschiebung zugunsten linear motiler Spermien registriert werden. Während die Verringerung der nicht linear motilen Subpopulation nur zufälligen Charakters ist, weist der Kreisläuferanteil post filtrationem einen signifikanten Rückgang auf (34,96 vs. 31,1 %). Der Zuwachs linear motiler Samenzellen ist jedoch von besonderem Interesse (7,36 vs. 12,43 %). Bei Zugrundelegung von Absolut- zahlenwerten, läßt sich (auch für oligozoosperme Ejakulate) ein nahezu 9-facher Anstieg linear motiler Spermatozoen von nativ 0,8 auf 7,1 Mio/ml nach Filtration demonstrieren. Ihre Spurgeschwindigkeit (curvilinear velocity-VCL) nimmt dabei überproportional zu (41,26 vs. 62,66 µm/s), während sich über alle motilen Spermien im Mittel nur eine filtrationsbedingte VCL-Erhöhung von 10 µm/s abzeichnet. Weiterhin kam ein Cell Counter + Analyser System (CASY®) zum Einsatz, das ein Verfahren der Partikelmeßtechnik nutzt. So gelang der Nachweis, daß die Glaswolle-Filtration unter Reduktion klein- und großkorpuskulärer Bestandteile (zelluläre und nichtzelluläre) eine deutliche Anreicherung einer Samenzell-Population mit medianen Membrandurchmesser von 3,47 µm bewirkt. Die Ergebnisse der morphologischen Differenzierung (strict criteria) stehen damit im Einklang. Nach Filtration konnte eine signifikante Zunahme der Normalform (13,33 vs. 19,16 %) bei adäquater Verminderung von Makro- und Mikroköpfen (6,5 vs. 3,03 %) sowie Vorstufen (8,33 vs. 5,96 %) registriert werden. Auf den raster-elektronen-mikroskopischen Aufnahmen wird deutlich, wie besonders membrandefekte Spermatozoen und muköses Eiweiß der Glaswolle-Faseroberfläche verhaften. / An efficient procedure for sperm preparation is presented using glass wool (microfibre code 112) in a special filter arrangement. Centrifugation as a means of spermatozoa concentration, a process which is extremely harmful to the sperm cells, can be dispensed with by making use of a concentration effect induced by the form of the vessel. The results that follow are mean values from 30 measurements. Computer-Assisted Sperm-motility Analysis (CASA) shows a significant rise of the sperm cell contents in the filtrate (27,45 vs. 69,56 million/ml) as compared with the native ejaculate. The distribution ratio of sperm populations observed after glass wool filtration provides favourable conditions for assisted reproduction. Reduction of the immotile portion to one fifth (54,53 vs. 11,66 %) yields a consecutive rise of the portion of motile sperms (39,53 vs. 82,06 %). Further specification of motile spermatozoa shows a shift in favour of sperms moving in a straight line. The decrease of the portion moving in circles is significant (34,96 vs. 31,1 %) after filtration, whereas the reduction in the subpopulation of sperms not moving in a straight line is of a rather incidental nature. Of particular interest, however, is the increase in sperm cells moving in straight lines (7,36 vs. 12,43 %). Basing considerations on absolute figures , a nine-fold increase in spermatozoa moving in straight lines, from the native value of 0,8 to 7,1 million/ml, can be demonstrated (even for oligozoospermial ejaculates) after filtration. Their curvilinear velocity (VCL) rises, in this connection, to a disproportionately high degree (41,26 vs. 62,66 µm/sec), whereas a filtration-induced rise of the VCL by only 10 µm/sec is observed for all motile spermatozoa on the average. Furthermore, a Cell Counter + Analyser System (CASY®) was employed making use of a particle test procedure. In this way, it could be proved that glass wool filtration produces a marked enrichment in a population of sperm cells with a mean membrane diameter of 3,47 µm with simultaneous reduction of the small- and large-corpuscular (cellular and non-cellular) fractions. In keeping with this are the results of the morphological differentiation (strict criteria). A significant increase in the standard form (13,33 vs. 19,16 %) with an adequate reduction in macro and micro heads (6,5 vs. 3,03 %) as well as in prestages (8,33 vs. 5,96 %) could be observed after filtration. Pictures taken with the electron-scan microscope clearly show that spermatozoa presenting membrane defects as well as mucous proteins, in particular, attach to the glass wool fibre surface.
4

Separação espermática pré refrigeração do sêmen equino / Sperm separation for cooling of equine sperm

Pessoa, Gilson Antonio January 2016 (has links)
As biotécnicas da reprodução na espécie equina avançaram na última década, tanto em conhecimento agregado por pesquisas como também pela demanda do mercado. No entanto, na espécie equina machos com subfertilidade são diagnosticados frequentemente com elevado número de espermatozoides com alterações morfológica e/ou imóveis. A utilização apenas de células viáveis para realizar o processo de resfriamento busca evitar perda de material (diluente) e produção de metabólitos tóxicos aos espermatozoides viáveis. O objetivo deste estudo foi utilizar a separação espermática (lã de vidro e centrifugação com Androcoll®) pré-resfriamento para incrementar a viabilidade do sêmen de garanhões pôneis refrigerados a 5ºC durante 48h. Os parâmetros motilidade, funcionalidade de membrana (HOST), viabilidade espermática (CFDA/PI), atividade mitocondrial e morfologia espermática foram avaliados no sêmen fresco e refrigerado (24 e 48h). A utilização da filtração por lã de vidro ou Androcoll® pré-resfriamento do sêmen equino selecionou espermatozoides com maior motilidade, funcionalidade de membrana, viabilidade espermática e atividade mitocondrial. Adicionalmente, a filtração por lã de vidro proporcionou refrigerar sêmen com elevado número de células morfologicamente normais sem perdas significativas de espermatozoides pelo processo de filtração. Tanto a técnica de lã de vidro como a centrifugação com Androcoll® mostraram-se eficientes em separar ejaculados com maior viabilidade para o resfriamento. Já a técnica de lã de vidro apresenta-se como uma técnica de baixo custo e de fácil execução para ser aplicada tanto para pequenos, ou grandes volumes de sêmen. / The reproduction biotechnologies in equine species have advanced in the last decade both in aggregate knowledge by research as well as the market demand. However, it in the equine species often with male subfertility where the ejaculate has a high number of sperm with morphological and / or property changes. The use of only viable cells to perform the cooling process seeks to avoid loss of material (diluent) and production of toxic metabolites to viable sperm. The aim of this study was to use the sperm separation (glass and spin wool with Androcoll®) pre-cooling to increase the viability of semen chilled ponies stallions at 5 ° C for 48 hours. We evaluated the motility parameters, membrane functionality (HOST), sperm viability (CFDA / PI), mitochondrial activity and morphology in fresh and chilled semen (24 and 48h). The use of filtration glass wool or Androcoll® pre-cooling of equine semen selected sperm with higher motility, functionality membrane, sperm viability and mitochondrial activity. In addition to filtration through glass wool afforded cooling semen with a high number of morphologically normal cells without significant losses of spermatozoids the filtration process. Both glass wool technique as centrifugation with Androcoll® were efficient in separating ejaculated more viability for cooling. Already glass wool technique presents itself as a low cost and simple technique to be applied to both small or large volumes of semen.
5

Separação espermática pré refrigeração do sêmen equino / Sperm separation for cooling of equine sperm

Pessoa, Gilson Antonio January 2016 (has links)
As biotécnicas da reprodução na espécie equina avançaram na última década, tanto em conhecimento agregado por pesquisas como também pela demanda do mercado. No entanto, na espécie equina machos com subfertilidade são diagnosticados frequentemente com elevado número de espermatozoides com alterações morfológica e/ou imóveis. A utilização apenas de células viáveis para realizar o processo de resfriamento busca evitar perda de material (diluente) e produção de metabólitos tóxicos aos espermatozoides viáveis. O objetivo deste estudo foi utilizar a separação espermática (lã de vidro e centrifugação com Androcoll®) pré-resfriamento para incrementar a viabilidade do sêmen de garanhões pôneis refrigerados a 5ºC durante 48h. Os parâmetros motilidade, funcionalidade de membrana (HOST), viabilidade espermática (CFDA/PI), atividade mitocondrial e morfologia espermática foram avaliados no sêmen fresco e refrigerado (24 e 48h). A utilização da filtração por lã de vidro ou Androcoll® pré-resfriamento do sêmen equino selecionou espermatozoides com maior motilidade, funcionalidade de membrana, viabilidade espermática e atividade mitocondrial. Adicionalmente, a filtração por lã de vidro proporcionou refrigerar sêmen com elevado número de células morfologicamente normais sem perdas significativas de espermatozoides pelo processo de filtração. Tanto a técnica de lã de vidro como a centrifugação com Androcoll® mostraram-se eficientes em separar ejaculados com maior viabilidade para o resfriamento. Já a técnica de lã de vidro apresenta-se como uma técnica de baixo custo e de fácil execução para ser aplicada tanto para pequenos, ou grandes volumes de sêmen. / The reproduction biotechnologies in equine species have advanced in the last decade both in aggregate knowledge by research as well as the market demand. However, it in the equine species often with male subfertility where the ejaculate has a high number of sperm with morphological and / or property changes. The use of only viable cells to perform the cooling process seeks to avoid loss of material (diluent) and production of toxic metabolites to viable sperm. The aim of this study was to use the sperm separation (glass and spin wool with Androcoll®) pre-cooling to increase the viability of semen chilled ponies stallions at 5 ° C for 48 hours. We evaluated the motility parameters, membrane functionality (HOST), sperm viability (CFDA / PI), mitochondrial activity and morphology in fresh and chilled semen (24 and 48h). The use of filtration glass wool or Androcoll® pre-cooling of equine semen selected sperm with higher motility, functionality membrane, sperm viability and mitochondrial activity. In addition to filtration through glass wool afforded cooling semen with a high number of morphologically normal cells without significant losses of spermatozoids the filtration process. Both glass wool technique as centrifugation with Androcoll® were efficient in separating ejaculated more viability for cooling. Already glass wool technique presents itself as a low cost and simple technique to be applied to both small or large volumes of semen.
6

Separação espermática pré refrigeração do sêmen equino / Sperm separation for cooling of equine sperm

Pessoa, Gilson Antonio January 2016 (has links)
As biotécnicas da reprodução na espécie equina avançaram na última década, tanto em conhecimento agregado por pesquisas como também pela demanda do mercado. No entanto, na espécie equina machos com subfertilidade são diagnosticados frequentemente com elevado número de espermatozoides com alterações morfológica e/ou imóveis. A utilização apenas de células viáveis para realizar o processo de resfriamento busca evitar perda de material (diluente) e produção de metabólitos tóxicos aos espermatozoides viáveis. O objetivo deste estudo foi utilizar a separação espermática (lã de vidro e centrifugação com Androcoll®) pré-resfriamento para incrementar a viabilidade do sêmen de garanhões pôneis refrigerados a 5ºC durante 48h. Os parâmetros motilidade, funcionalidade de membrana (HOST), viabilidade espermática (CFDA/PI), atividade mitocondrial e morfologia espermática foram avaliados no sêmen fresco e refrigerado (24 e 48h). A utilização da filtração por lã de vidro ou Androcoll® pré-resfriamento do sêmen equino selecionou espermatozoides com maior motilidade, funcionalidade de membrana, viabilidade espermática e atividade mitocondrial. Adicionalmente, a filtração por lã de vidro proporcionou refrigerar sêmen com elevado número de células morfologicamente normais sem perdas significativas de espermatozoides pelo processo de filtração. Tanto a técnica de lã de vidro como a centrifugação com Androcoll® mostraram-se eficientes em separar ejaculados com maior viabilidade para o resfriamento. Já a técnica de lã de vidro apresenta-se como uma técnica de baixo custo e de fácil execução para ser aplicada tanto para pequenos, ou grandes volumes de sêmen. / The reproduction biotechnologies in equine species have advanced in the last decade both in aggregate knowledge by research as well as the market demand. However, it in the equine species often with male subfertility where the ejaculate has a high number of sperm with morphological and / or property changes. The use of only viable cells to perform the cooling process seeks to avoid loss of material (diluent) and production of toxic metabolites to viable sperm. The aim of this study was to use the sperm separation (glass and spin wool with Androcoll®) pre-cooling to increase the viability of semen chilled ponies stallions at 5 ° C for 48 hours. We evaluated the motility parameters, membrane functionality (HOST), sperm viability (CFDA / PI), mitochondrial activity and morphology in fresh and chilled semen (24 and 48h). The use of filtration glass wool or Androcoll® pre-cooling of equine semen selected sperm with higher motility, functionality membrane, sperm viability and mitochondrial activity. In addition to filtration through glass wool afforded cooling semen with a high number of morphologically normal cells without significant losses of spermatozoids the filtration process. Both glass wool technique as centrifugation with Androcoll® were efficient in separating ejaculated more viability for cooling. Already glass wool technique presents itself as a low cost and simple technique to be applied to both small or large volumes of semen.
7

JÄMFÖRELSE AV KLIMATPÅVERKANFÖR GLASULL OCH POLYURETAN : MPARISON OF CLIMATE IMPACT FOR GLASS WOOL AND POYURETHANE

Abraham, Kaleb, Lust, Andreas January 2023 (has links)
This study examines the climate impact of the thermal insulation materials, glass wool and polyurethane. Two wall constructions with a size of one square meter are used in the study to compare their carbon footprints and determine which material has the lowest environmental impact. For the walls to be comparable, they need to have the same U-value. The study will be limited to only examining the materials from a cradle-to-gate perspective. Literature searches will be conducted for data collection. For the calculation of environmental impact, the study will examine Life Cycle Assessment (LCA), Environmental Product Declarations (EPDs), and the Boverket’s Climate Declaration.Environmental data for building materials is calculated using LCA, and from this, EPDs can be generated, which contain summarized environmental data. This study collects environmental data from EPDs Boverket’s Climate Database. U-values are calculated using the U- and λ-value method, and then the mean value is derived. Subsequently, the quantities of the materials are determined, and the walls' total Global Warming Potential (GWP) is calculated.According to the results of the study, walls with polyurethane and glass wool insulation show a significant difference in their carbon footprints. GWP calculations show that the wall with polyurethane insulation emits approximately 33 kg CO2e (carbon dioxide equivalents), while the wall with glass wool insulation emits around 17 kg CO2e. The results also indicate that the insulation layers alone exhibit a significant difference in carbon footprint, approximately 20 kg CO2e for polyurethane and 4.0 kg CO2e for glass wool. The significant difference may be attributed to the oil-based production of polyurethane. The study also found that the manufacturing stage contributes the most to the climate impact for both insulation materials.When selecting insulation materials, other material properties also need to be investigated, such as fire resistance, acoustic performance, and more. The economic aspect also plays a significant role in the selection process.From an environmental perspective, the conclusion indicates that glass wool insulation is the better choice. / I denna undersökning kommer klimatpåverkan av värmeisoleringsmaterialen glasull och polyuretan undersökas. Två väggkonstruktioner med en storlek på en kvadratmeter används i studien för att jämföra dess koldioxidavtryck för att avgöra vilket material som har lägst miljöpåverkan. För att väggarna ska vara jämförbara behöver de ha samma U-värde. Studien kommer begränsa sig till att bara undersöka materialen från vagga-till-port.Litteratursökningar kommer genomföras för informationsinsamling. För beräkning av miljöpåverkan kommer studien undersöka LCA (livscykelanalys), EPD:er(miljövarudeklarationer) och Boverkets Klimatdeklaration.Miljödata för byggnadsmaterial beräknas genom LCA, och från detta kan man ta fram EPD:er som innehåller dess sammanfattade miljödata. Den här studien hämtar miljödata från EPD:er och Boverkets Klimatdatabas. Beräkning av U-värden utfördes med U- och λ-värdesmetodendär sedan medelvärdet tas fram. Därefter mängdas materialen och sedan beräknas väggarnas totala GWP (global uppvärmningspotential).Enligt studiens resultat visar väggarna med polyuretan- och glasullsisolering en stor skillnad på deras koldioxidavtryck. Beräkningar av GWP visar väggen med polyuretanisolering har utsläpp på ca 33 kg CO2e (koldioxidekvivalenter) medan väggen med glasullisolering har utsläpp på ca 17 kg CO2e. Resultatet visar också att enbart värmeisoleringsskikten har stor skillnad i koldioxidavtrycket, ca 20 kg CO2e för polyuretan och ca 4,0 kg CO2e för glasull.Den stora skillnaden kan bero på att framställningen av polyuretan är oljebaserad. Studien visade också att den största klimatpåverkan kommer från tillverkningsskedet för båda isoleringsmaterialen.Vid val av isoleringsmaterial behöver även andra materialegenskaper undersökas till exempelbrandmotstånd, akustik med mera. Även den ekonomiska aspekten har betydelse för valet.Slutsatsen ur ett miljöperspektiv visar att glasullsisoleringen är det bättre valet.
8

Efeito da adi??o de microfibras de l? de vidro na tenacidade ? ruptura de pastas de cimento para po?os de petr?leo

Paiva, Luanna Carla Matias 02 September 2013 (has links)
Made available in DSpace on 2014-12-17T14:08:56Z (GMT). No. of bitstreams: 1 LuannaCMP_DISSERT.pdf: 3195149 bytes, checksum: 9c2b834c5beeb3439f6a0d1955159637 (MD5) Previous issue date: 2013-09-02 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / Although there are a wide variety of additives that act in fresh state, to adjust the properties of cement, there is also a search by additions that improve the tenacity of the cement in the hardened state. This, in turn, can often be increased by inserting fibers, which act on the deflection of microcracks. This study aimed to use a microfiber glass wool (silica-based) as an additive reinforcing the cement matrix, improving the rupture tenacity, in order to prevent the propagation of microcracks in the cement sheath commonly found in oil wells submitted to high temperatures. The fibers were added at different concentrations, 2 to 5% (BWOC) and varied average sizes, grinding for 90 s, 180 s, 300 s, 600 s. The cement slurries were made with a density of 1,90 g/ cm3 (15,6 lb/gal), using Portland cement CPP- Special Class as the hydraulic binder and 40% silica flour. The characterization of the fiber was made by scanning electron microscopy (SEM), particle size by sieving, X-ray fluorescence (XRF), X-ray diffraction (XRD) and thermogravimetry (TG / DTG). Were performed technological tests set by the API (American Petroleum Institute) by rheology, stability, free water, compressive strength, as well as testing rupture energy, elastic modulus and permeability. The characterization results showed good thermal stability of the microfiber glass wool for application in oil wells submitted to steam injection and, also, that from the particle size data, it was possible to suggest that microfibers milled up to 300 s, are ideal to act as reinforcement to the cement slurries. The rheological parameters, there was committal of plastic viscosity when larger lengths were inserted of microfiber (F90). The values obtained by free water and stability were presented according to API. The mechanical properties, the incorporation of microfiber to the cement slurries gave better rupture tenacity, as compared to reference cement slurries. The values of compressive strength, elastic modulus and permeability have been maintained with respect to the reference cement slurries. Thus, cement slurries reinforced with microfiber glass wool can ensure good application for cementing oil wells submitted to steam injection, which requires control of microcracks, due to the thermal gradients / Embora exista uma grande variedade de aditivos que atuam no estado fresco, para ajuste das propriedades do cimento, existe tamb?m uma busca por adi??es que melhorem a tenacidade do cimento no estado endurecido. Esta, por sua vez, pode comumente ser aumentada pela inser??o de fibras, as quais agem na deflex?o de microtrincas. Este trabalho tem como objetivo utilizar microfibras de l? de vidro (? base de s?lica) como aditivo de refor?o ? matriz ciment?cia, melhorando a tenacidade ? ruptura, a fim de evitar a propaga??o de microfissuras na bainha cimentante comumente encontradas em po?os de petr?leo submetidos a altas temperaturas. As fibras foram adicionadas em diferentes teores, de 2 a 5% (BWOC), e variados tamanhos m?dios, obtidos variando o tempo de moagem de 90 s, 180 s, 300 s e 600 s. As pastas foram formuladas com densidade de 1,90 g/ cm3 (15,6 lb/gal), utilizando o cimento Portland CPP-Classe Especial como aglomerante hidr?ulico e 40% de s?lica flour. A caracteriza??o da fibra foi feita por microscopia eletr?nica de varredura (MEV), granulometria por peneiramento, fluoresc?ncia de raios X (FRX), difra??o de raios X (DRX) e termogravimetria (TG/DTG). Foram realizados ensaios tecnol?gicos padronizados pela API (American Petroleum Institute) de reologia, estabilidade, ?gua livre, resist?ncia ? compress?o, bem como testes de energia de ruptura, m?dulo de elasticidade e permeabilidade. Os resultados da caracteriza??o mostraram boa estabilidade t?rmica da microfibra de l? de vidro para aplica??o em po?os submetidos ? inje??o de vapor. A partir dos dados de granulometria, foi poss?vel verificar que microfibras mo?das at? 300 s s?o ideais para agirem como refor?o ? pasta de cimento. Dos par?metros reol?gicos, houve o comprometimento da viscosidade pl?stica quando foram inseridos comprimentos maiores de microfibra (F90). Os valores obtidos de ?gua livre e estabilidade se apresentaram conformes ? norma API. Das propriedades mec?nicas, a incorpora??o de microfibra ? pasta de cimento conferiu melhor tenacidade ? ruptura, comparada a pasta de refer?ncia. Os valores obtidos de resist?ncia ? compress?o, m?dulo de elasticidade e permeabilidade foram mantidos com rela??o ? pasta padr?o. Desse modo, pastas ciment?cias refor?adas com microfibra de l? de vidro podem garantir boas aplica??es em cimenta??o de po?os de petr?leo sujeitas ? inje??o de vapor, que exija o controle de microfissuras em virtude do gradiente de temperatura
9

Livscykelanalys och livscykelkostnad för byggnad isolerad med hampfiber jämfört med alternativ isolering / Life cycle analysis and life cycle cost of building insulated with hemp fiber compared to alternative insulation

Eriksson, Ylva, Mathilda, Hult, Karlsmo, Sara January 2021 (has links)
Det finns en oro kring konsekvenserna av ökade växthusgasutsläpp. Därför har bland annat EU:s medlemsländer tecknat avtal om att minska utsläppen. I Sverige har det lett till krav att från och med 2022 redovisa byggmaterials miljöpåverkan genom klimatdeklarationer. Byggsektorn har potential att minska klimatpåverkan. Byggnadsmaterial ger olika utsläpp av växthusgaser och valet av material är viktigt. Isoleringsmaterial med naturlig härkomst anses orsaka mindre utsläpp än konventionell isolering. Hampa är ett exempel på ett naturligt material som kan användas i småhusbebyggelse. Hampan kan bli en kolsänka då biomaterial binder kol. Tyvärr finns det idag mycket begränsad forskning på just hampfiberisolering i svenskt klimat.  Syftet med studien är att bidra med ökad kunskap inför valet av isoleringsmaterial i ett småhus, av modellen Eneryda av Rörvikshus, placerat i Växjö. I arbetet jämförs klimatpåverkan och kostnader för isoleringsmaterialen hamp-, cellulosa- och glasullsisolering genom en livscykelanalys (LCA) och en livscykelkostnad (LCC) i en vald husmodell. I studien undersöks skedena A-D, d.v.s. från vagga till grav. Resultatet visar att byggnaden isolerad med hampfiber orsakar det lägsta nettoutsläppet på 124 följt av cellulosa 132 och glasull 139 CO₂e/m². Kostnaden för byggnaden med isolering av hampfiber är 5467, cellulosa 4830 och glasull 4861 SEK/m²BOA. Genom att välja hampfiberisolering istället för glasull kan utsläppen för husmodellen Eneryda minskas med 12 % samtidigt som kostnaden ökar med 20 %. Att välja cellulosaisolering i stället för glasullsisolering ger en minskning av nettoutsläppen med 5 % och kostnaderna förblir detsamma.  Studiens känslighetsanalyser visar effekten av indata. Om råvaran till cellulosa byts ut från oanvänt papper till återvunnen råvara orsakar det att nettoutsläppen för byggnaden Eneryda minskar med 13 %. Det innebär att småhuset Eneryda isolerad med cellulosa från återvunnen produkt orsakar 15 % lägre utsläpp än glasullshuset - utan att påverka priset. Största påverkan på nettoutsläppen hade Enerydas värmesystem. Att använda bergvärme istället för Veab:s fjärrvärme ökade nettoutsläppen med 56 – 63 %. Slutligen ledde resultatet av studien till en diskussion om avsaknaden av en entydig definition och metod för användandet av biogent kol i klimatdeklarationer. Att exkludera biogent kol leder till att hampfiberisoleringen bidrar med högst utsläpp tätt följt av cellulosan och sist glasullsisoleringen som släpper ut minst. Studiens resultat påvisar vikten av vaksamhet och att Boverket borde blir tydligare kring det biogena kolet i klimatberäkningar. Enheten bör utvecklas mer av institut för standarder. Av resultaten framgår också vikten av att ta tidsaspekten av biomaterialets förnyelsetid i beaktande vid beräkningarna för att material som hampfiber binder kol snabbare än exempelvis trä. / The concern of climate change has influenced the building sector in Sweden to become more climate neutral. The choice of building materials affect the emissions of carbon dioxide equivalents [CO₂e]. The purpose of the study is to provide more basis for the choice of insulation material looking into the climate- and cost implication of hemp fibre, cellulose and stone wool insulation.  The study includes an accounting-LCA from cradle to grave (A – D) and an LCC. The study looks at the climate shell of a one-story single-family house, model Eneryda from Rörvikshus, in Växjö over the lifetime 50 years.  The result shows that Eneryda net emissions for hemp fiber insulation is 124 CO₂e/m²BOA and the cost is 5467 SEK/m2 BOA. The result of emissions for the hempfiber-model is 12% less and the cost is 20% higher than the glass wool-model. Cellulose insulation results in net emissions of 132 CO₂e/m² and a cost of 4830 SEK/m2 BOA. Cellulose results in 5% less emissions and nearly the same cost as the glass wool building.
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The Impact of Insulation Materials on a Climate Declaration : A Study of a Swedish Preschool

Hallkvist, Isabelle, Nilsson, Elin January 2021 (has links)
To reach the net-zero carbon goal by 2045, the Swedish government want to push the building and construction sector to lower their greenhouse gas emissions. This push is performed by implementing a law requiring building developers to perform a climate declaration over greenhouse gas emissions, to receive a building’s final clearance. The climate declaration is limited to only include emissions from material extraction until completed building. However, there is a varying knowledge level in the industry regarding how to perform a climate declaration as well as how different materials impact the result. Therefore, this study aims to bring clarity concerning the topic, by investigating where the major and minor climate impacts occur in a building process. Additionally, the impact of different insulations materials and how they influence the result of a climate declaration is studied. To answer the research questions, a climate declaration is performed on a Swedish preschool. The insulation material in the building is altered between glass wool, stone wool, cellulose fibre, foam glass, and polystyrene insulation in different scenarios to see how it impacts the result. The stone wool scenarios use both carbon neutral and non-carbon neutral insulation. Cellulose fibre uses both loose wool with data from an EPD and board insulation with data from Boverket’s climate database in the scenarios. The major climate impact derives from the product stage (A1–A3), meaning material selection have a significant impact on the climate declaration result. The building element with the highest climate impact is the inner walls followed by the foundation, while the floor construction, roof and outer walls have the lowest climate impact. On a material level, plaster board, building plywood and concrete have the highest climate impact in the reference building. The cedar panel have the lowest climate impact and is the only carbon negative material in the reference building. However, this is due to different assumptions made in the climate impact data concerning the binding of carbon in organic materials. The results showed that the insulation material with the highest climate impact is non-carbon neutral stone wool that is 16 % higher than the original construction with glass wool, while loose cellulose wool has the lowest climate impact. The climate impact from the scenario with non-carbon neutral stone wool in the wall and roof construction is 33 % higher compared to the corresponding loose cellulose wool scenario. The scenario with the lowest climate impact, with loose cellulose wool, is approximately 13 % lower than the corresponding glass wool scenario. The carbon neutral stone wool scenario has a similar result to glass wool. Foam glass has a 9.5 % higher climate impact compared to polystyrene insulation in the foundation. Regarding the selection of insulation material, it influences the climate declaration by changing the climate impact. The influence derives from a combination of climate impact per unit and material quantity used in the building. The material quantity is partly dependant on the thermal conductivity (λ-value) of the insulation material. The climate declaration shows a limited view of a building’s environmental impact for a limited part of its lifecycle. Therefore, we would recommend additional lifecycle stages and environmental impacts to be part of the climate declaration in the future, as a means to avoid suboptimization and unintentional problem shifting. / För att nå klimatneutralitetsmålet 2045 vill den svenska regeringen driva bygg- och fastighetssektorn till att sänka sina växthusgasutsläpp. Denna insats utförs genom att införa en lag som kräver att byggherrar utför en klimatdeklaration över växthusgasutsläpp för att få ett slutbesked för byggnaden. Klimatdeklarationen är begränsad till att endast omfatta utsläpp från materialutvinning fram till färdig byggnad. Det finns dock en varierande kunskapsnivå i branschen om hur en klimatdeklaration utförs samt hur olika material påverkar resultatet. Därför syftar denna studie till att ge klarhet angående ämnet genom att undersöka var de större och mindre inflytandena på klimatpåverkan förekommer i en byggprocess. Dessutom studeras effekterna av olika isoleringsmaterial och hur de påverkar resultatet av en klimatdeklaration. För att besvara frågeställningarna utförs en klimatdeklaration på en svensk förskola. Isoleringsmaterialet i byggnaden ändras mellan glasull, stenull, cellulosafiber, skumglas och cellplast i olika scenarier för att se hur det påverkar resultatet. I stenullscenarierna används både koldioxidneutral och icke-koldioxidneutral isolering. Cellulosafibrer använder både lösull med data från en EPD och skivisolering med data från Boverkets klimatdatabas i scenarierna. Den största klimatpåverkan kommer från produktstadiet (A1–A3), vilket innebär att materialvalet har en betydande inverkan på klimatdeklarationsresultatet. Byggnadselementet med störst klimatpåverkan är innerväggarna följt av grunden, medan bjälklaget, taket och ytterväggarna har lägst klimatpåverkan. På materialnivå har gipsskivor, plywood och betong den högsta klimatpåverkan i referensbyggnaden. Cederpanelen har lägst klimatpåverkan och är det enda koldioxidnegativa materialet i referensbyggnaden. Detta beror dock på olika antaganden i klimatpåverkan angående bindningen av kol i organiska material. Resultaten visade att isoleringsmaterialet med den högsta klimatpåverkan är icke-koldioxidneutral stenull, som är 16 % högre än originalkonstruktionen med glasull, medan lös cellulosaull har lägst klimatpåverkan. Klimatpåverkan från scenariot med icke koldioxidneutral stenull i vägg- och takkonstruktion är 33 % högre jämfört med motsvarande scenario med lös cellulosaull. Scenariot med lägst klimatpåverkan, med lös cellulosaull, är cirka 13 % lägre än motsvarande glasullscenario. Det koldioxidneutrala stenullscenariot har ett liknande resultat som glasull. Skumglas har 9,5 % högre klimatpåverkan jämfört med cellplasten i grunden. När det gäller valet av isoleringsmaterial påverkar det klimatdeklarationen genom att förändra klimatpåverkan. Påverkan härstammar från en kombination av klimatpåverkan per enhet och mängden material som används i byggnaden. Mängden material beror delvis på isoleringsmaterialets värmekonduktivitet (λ-värde). Klimatdeklarationen visar en begränsad bild av en byggnads miljöpåverkan under en begränsad del av dess livscykel. Därför rekommenderar vi att ytterligare livscykelstadier och miljöindikatorer ingår i klimatdeklarationen i framtiden, för att undvika suboptimeringar och oavsiktliga problembyten.

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