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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.
11

Low Temperature Performance of Wax Modified Mastic Asphalt

Butt, Ali Azhar January 2009 (has links)
The current interest in energy saving asphalt production techniques is great and several new processes have been developed to reduce the mixing and compaction temperatures for hot mix asphalt. In particular, mastic asphalt products (Gussasphalt) require high working temperatures, and harder requirements concerning bitumen fumes and carbon dioxide emissions have been introduced for such products. Consequently, the need of a new means of producing and placing mastic asphalt at lower temperatures is particularly large. One way of reducing asphalt mixture temperature is by using special flow improving additives like wax. This technique has successively been tried in several studies for polymer modified mastic asphalt used for bridge decks and parking areas in Sweden. However, there still are uncertainties about possible negative impact on crack susceptibility at lower temperatures due to the addition of wax. In this study, 4% montan wax (Asphaltan A) was used for one particular polymer modified mastic asphalt product. Type and amount of wax additive was selected based on results from earlier studies. The impact on binder, binder/filler mixtures and mastic asphalt from production was tested in the laboratory, focusing on low temperature performance. The bending beam rheometer (BBR) was used for determining low temperature creep compliance and the tensile stress restrained specimen test (TSRST) for determining fracture temperatures. Binder properties were determined using dynamic mechanical analysis (DMA), Fourier transform infrared (FTIR) spectroscopy and conventional tests (softening point, penetration, elastic recovery, Fraass breaking point, viscosity and storage stability). Aging was performed using the rolling thin film oven test (RTFOT) at 200°C. As expected, the addition of wax to the polymer modified binder showed a viscosity reduction at higher temperatures, corresponding to a similar positive effect of more than 10°C on production and laying temperature for the mastic asphalt. DMA and BBR results showed some increase in stiffness and a more elastic response of the wax modified binder at medium and low temperatures. The TSRST fracture temperature was 5 °C higher for the mastic asphalt containing 4% wax, indicating however no dramatic negative impact on crack susceptibility.
12

Modeling static creep with stress reversals of mastic asphalt.

Tigabu, Romel January 2011 (has links)
This thesis studies the strain response of mastic asphalt to arbitrary tension, arbitrary compression, alternating tension/compression, loading, zigzag loading and sinusoidal loading. In order to model the strain response to different loading histories, the scissors model is employed. Matlab modules are developed that are able to predict strain response not only for creep loading but also for other types of non constant stress loading such as zigzag loading and sinusoidal loading. In addition, another phenomological model, i.e. the viscoelastoplastic continuum damage model, is summarized and discussed in detail with respect to its applicability for the available data set.
13

On the quantification of healing in asphalt materials

Varma, Remya January 2021 (has links)
Asphalt materials exhibit self-healing characteristics. In order to evaluate the healing capabilities of these materials, numerous investigations are carried out by researchers. These investigations include various definitions of healing and mechanical test methods to quantify the extent of healing. Irrespective of these extensive studies, there is no unique method to evaluate the healing in asphalt materials. The biasedness to the test conditions and complexity due to the involvement of other phenomena such as stress relaxation and strain recovery make the characterization of healing a challenging process. The work presented in this thesis includes the development of experimental and analytical approaches to contribute to the understanding of healing in asphalt materials. The thesis focuses on both fracture mechanics and damage mechanics-based approaches to evaluate the healing in asphalt materials. In the first case, three-point bending tests are carried out to characterize the healing following the fracture. The experimental protocol is carefully designed to avoid the effect due to low temperature physical hardening of the material during the rest period. Different healing indices appealing to linear elastic fracture mechanics and viscoelastic fracture mechanics are compared. While healing is generally defined based on the recovery of certain parameters following the rest period, the comparison across healing indices shows that the quantitative interpretations of healing are dependent on the post-processing methods. The damage mechanics-based approach discussed in this study includes creep and recovery tests in shear. Here, unlike the first case, the samples are not fractured during the test. The damage is considered to be a part of the viscoplastic deformation and the recovery of viscoplastic deformation is defined as the healing. The method proposed in this study is useful to isolate the viscoelastic effects to quantify the healing of damage. / Asfaltmaterial uppvisar självläkande egenskaper. För att utvärdera dess läkande förmågor utförs många undersökningar av forskare. Dessa undersökningar inkluderar olika definitioner av läkning och mekaniska testmetoder för att kvantifiera graden av läkningen. Trots dessa omfattande studier finns det ingen unik metod för att utvärdera läkning i asfaltsmaterial. Påverkan av testförhållandena och komplexiteten från inverkan av andra fenomen, såsom spänningsrelaxation och töjningsåterhämtning, gör karakteriseringen av läkning en utmanande process. Arbetet som presenteras i denna uppsats inkluderar utvecklingen av experimentella och analytiska metoder för att bidra till förståelsen av läkning i asfaltsmaterial. Uppsatsen fokuserar på både brottmekaniks- och skademekaniksbaserade metoder för att utvärdera läkning i asfaltsmaterial. I det första fallet utförs trepunktsböjningstest för att karakterisera läkningen efter brott. Det experimentella protokollet är noggrant designat för att undvika effekten av hårdnande vid låg temperatur under viloperioden. Dessutom jämförs olika läkningsindex baserade på linjärelastisk brottmekanik och viskoelastisk brottmekanik. Trots att läkning generellt definieras baserat på återhämtningen av vissa parametrar efter viloperioden, så visar jämförelsen av läkningsindexen att den kvantitativa tolkningen av läkning beror på metoderna för efterbehandling.  Den skademekaniksbaserade metoden som diskuteras i denna studie inkluderar kryp- och återhämtningstest i skjuvning. Till skillnad mot det första fallet så spricker här inte proven. Skadan anses istället vara del av den viskoplastiska deformationen och återhämtningen av viskoplastisk deformation är definierad som läkning. Metoden som föreslås i denna studie är användbar för att isolera de viskoelastiska effekterna för att kvantifiera läkningen av skada.
14

Influência do fíler mineral em propriedades de misturas asfálticas densas / Mineral filler influence on hot mix asphalt properties

Bardini, Vivian Silveira dos Santos 25 March 2013 (has links)
Esta pesquisa tem por objetivo contribuir para o melhor entendimento dos efeitos do fíler mineral sobre o comportamento mecânico de misturas asfálticas densas, particularmente em relação ao tipo e teor de fíler. O comportamento mecânico de misturas asfálticas densas foi avaliado em função do tipo e teor de fíler (diferentes propriedades físicas, geométricas, mineralógica e comportamento físico-químico), do tipo de agregado (diferentes origens mineralógicas) e do tipo de ligante asfáltico (diferentes consistências). Para alcançar o objetivo geral, a pesquisa foi dividida em três partes: o estudo da mistura asfáltica completa, através de ensaios mecânicos; o estudo do mástique, resultante da mistura de fíler com ligante asfáltico, através dos ensaios comumente aplicados aos ligantes asfálticos puros; e o estudo do comportamento de trincamento dos mástiques nas temperaturas intermediárias, através das características de energia fratura. A análise de variância dos resultados auxiliou na identificação dos fatores com influência significativa nas propriedades apresentadas pelas misturas e mástiques asfálticos. Quanto aos resultados de vida de fadiga, as misturas asfálticas compostas com cal hidratada apresentaram as maiores vidas de fadiga e quanto maior o teor de fíler, maior a vida de fadiga. Em relação à deformação permanente, as misturas asfálticas contendo o menor teor de fíler apresentam os menores valores de deformação não recuperável, enquanto que as misturas contendo o valor intermediário de fíler apresentam os maiores valores. As propriedades reológicas dos mástiques mostraram que a adição de fíler torna o ligante asfáltico mais rígido e a cal hidratada é o fíler que provoca o maior aumento do valor do G*. A elasticidade do mástique aumenta com a adição dos fileres e é mais expressivo para os mástiques compostos pelo fíler de cal hidratada e cimento Portland. Quanto maior o teor de fíler utilizado, maior a temperatura correspondente a G*/sen \'delta\' \'> ou =\' 1,0 kPa da especificação Superpave, o que pode se refletir em misturas asfálticas com maior resistência à deformação permanente. Nas propriedades a baixa temperatura, a utilização de maiores teores de fíler prejudicam a resposta ao trincamento a baixas temperaturas e diminuem a eficiência na dissipação das tensões formadas durante a contração do ligante asfáltico, quando a temperatura do pavimento cai abruptamente, aumentando a formação de trincas e fissuras. Analisando os resultados da energia de fratura, a adição de fíler no mástique diminui a resistência ao trincamento por fadiga nas temperaturas intermediárias, porém a presença de fíler na mistura durante o envelhecimento torna seus efeitos menos prejudiciais. / The objective of this research is to contribute to the better understanding of mineral filler effects on the mechanical behavior of hot mix asphalt (HMA), particularly related to the filler type and content. The hot mix asphalt mechanical behavior was evaluated according to: the filler type and content (different physical, geometrical, mineralogical properties, and the physical-chemical behavior); the aggregate type (different mineralogical source); and the asphalt binder type (different consistency). To reach the global objective, the research was divided in three parts: the study of the complete HMA, through the mechanical tests; the study of the mastic, resulting from mixture of mineral filler and asphalt binder, through tests commonly applied to pure asphalt binder; and the study of cracking performance behavior at intermediate temperature, through the fracture energy characteristics. The analysis of variance of the results assisted to identify the factors with significant influence in properties of the hot mix and mastic asphalt. Regarding the results of the fatigue life, the HMA composed with the hydrated lime presented the longer fatigue life and the higher the filler content the longer the fatigue life. Related to the permanent deformation, the HMA containing the lowest content of filler presented the lowest non-recoverable strain, while the HMA containing an intermediate value of filler presented the highest values. The mastics rheological properties showed that addition of filler makes the asphalt binder stiffer, and the hydrated lime causes the greatest increase of G*. The mastic elasticity increases with the filler, and its more notorious when the mastic is composed by the hydrated lime and Portland cement. The higher the filler content, the higher the temperature corresponding to G*/sen \'delta\' \'> ou =\' 1,0 kPa of the Superpave specification, which may be reflected in HMA with higher permanent deformation resistance. At low temperature properties, the use of higher filler content prejudice the low temperatures cracking response, and decrease the efficiency of stress dissipation formed during contraction of the asphalt binder when the pavement temperature drops abruptly, increasing the formation of cracks and fissures. Analyzing the energy fracture results, adding filler to the mastic decrease the cracking resistance by fatigue at intermediate temperature, but the filler presence in the mixture during aging makes the effect less damaging.
15

Influência do fíler mineral em propriedades de misturas asfálticas densas / Mineral filler influence on hot mix asphalt properties

Vivian Silveira dos Santos Bardini 25 March 2013 (has links)
Esta pesquisa tem por objetivo contribuir para o melhor entendimento dos efeitos do fíler mineral sobre o comportamento mecânico de misturas asfálticas densas, particularmente em relação ao tipo e teor de fíler. O comportamento mecânico de misturas asfálticas densas foi avaliado em função do tipo e teor de fíler (diferentes propriedades físicas, geométricas, mineralógica e comportamento físico-químico), do tipo de agregado (diferentes origens mineralógicas) e do tipo de ligante asfáltico (diferentes consistências). Para alcançar o objetivo geral, a pesquisa foi dividida em três partes: o estudo da mistura asfáltica completa, através de ensaios mecânicos; o estudo do mástique, resultante da mistura de fíler com ligante asfáltico, através dos ensaios comumente aplicados aos ligantes asfálticos puros; e o estudo do comportamento de trincamento dos mástiques nas temperaturas intermediárias, através das características de energia fratura. A análise de variância dos resultados auxiliou na identificação dos fatores com influência significativa nas propriedades apresentadas pelas misturas e mástiques asfálticos. Quanto aos resultados de vida de fadiga, as misturas asfálticas compostas com cal hidratada apresentaram as maiores vidas de fadiga e quanto maior o teor de fíler, maior a vida de fadiga. Em relação à deformação permanente, as misturas asfálticas contendo o menor teor de fíler apresentam os menores valores de deformação não recuperável, enquanto que as misturas contendo o valor intermediário de fíler apresentam os maiores valores. As propriedades reológicas dos mástiques mostraram que a adição de fíler torna o ligante asfáltico mais rígido e a cal hidratada é o fíler que provoca o maior aumento do valor do G*. A elasticidade do mástique aumenta com a adição dos fileres e é mais expressivo para os mástiques compostos pelo fíler de cal hidratada e cimento Portland. Quanto maior o teor de fíler utilizado, maior a temperatura correspondente a G*/sen \'delta\' \'> ou =\' 1,0 kPa da especificação Superpave, o que pode se refletir em misturas asfálticas com maior resistência à deformação permanente. Nas propriedades a baixa temperatura, a utilização de maiores teores de fíler prejudicam a resposta ao trincamento a baixas temperaturas e diminuem a eficiência na dissipação das tensões formadas durante a contração do ligante asfáltico, quando a temperatura do pavimento cai abruptamente, aumentando a formação de trincas e fissuras. Analisando os resultados da energia de fratura, a adição de fíler no mástique diminui a resistência ao trincamento por fadiga nas temperaturas intermediárias, porém a presença de fíler na mistura durante o envelhecimento torna seus efeitos menos prejudiciais. / The objective of this research is to contribute to the better understanding of mineral filler effects on the mechanical behavior of hot mix asphalt (HMA), particularly related to the filler type and content. The hot mix asphalt mechanical behavior was evaluated according to: the filler type and content (different physical, geometrical, mineralogical properties, and the physical-chemical behavior); the aggregate type (different mineralogical source); and the asphalt binder type (different consistency). To reach the global objective, the research was divided in three parts: the study of the complete HMA, through the mechanical tests; the study of the mastic, resulting from mixture of mineral filler and asphalt binder, through tests commonly applied to pure asphalt binder; and the study of cracking performance behavior at intermediate temperature, through the fracture energy characteristics. The analysis of variance of the results assisted to identify the factors with significant influence in properties of the hot mix and mastic asphalt. Regarding the results of the fatigue life, the HMA composed with the hydrated lime presented the longer fatigue life and the higher the filler content the longer the fatigue life. Related to the permanent deformation, the HMA containing the lowest content of filler presented the lowest non-recoverable strain, while the HMA containing an intermediate value of filler presented the highest values. The mastics rheological properties showed that addition of filler makes the asphalt binder stiffer, and the hydrated lime causes the greatest increase of G*. The mastic elasticity increases with the filler, and its more notorious when the mastic is composed by the hydrated lime and Portland cement. The higher the filler content, the higher the temperature corresponding to G*/sen \'delta\' \'> ou =\' 1,0 kPa of the Superpave specification, which may be reflected in HMA with higher permanent deformation resistance. At low temperature properties, the use of higher filler content prejudice the low temperatures cracking response, and decrease the efficiency of stress dissipation formed during contraction of the asphalt binder when the pavement temperature drops abruptly, increasing the formation of cracks and fissures. Analyzing the energy fracture results, adding filler to the mastic decrease the cracking resistance by fatigue at intermediate temperature, but the filler presence in the mixture during aging makes the effect less damaging.
16

Determination of thermal conductivity for mastic asphalt by combining previously performed laboratory work and TASEF / Bestämning av termisk konduktivitet för gjutasfalt genom kombination av tidigare utfört laborationsarbete och TASEF

Kruse Lindgren, Martin January 2021 (has links)
Mastic asphalt is a material which in Sweden mainly is used as coating for bridges, parking decks, courtyards and terraces. Mastic asphalt is a material built-up by a combination of bitumen (a type of binder), well-graded aggregate (consists of both coarse and fine ballast), filler, sand and sometimes also fine graded macadam. Mastic asphalt is described as a material which in Sweden have potential to expand further.  At the same time, it is becoming increasingly popular to construct buildings with solid timber frames. In 2019, the Swedish market for forestry and algaculture was analyzed, after which cross-laminated timber proved to be the construction-material that increases most in popularity. In constructions, mastic asphalt and timber may be combined. In Växjö Sweden for example, a parking deck called Limnologen is constructed with both timber frames and mastic asphalt as pavement. Another example were mastic asphalt and timber have been combined is an enormous car park built in Studen, Switzerland, which have 2142 parking lots. The aim of this master thesis was to develop a temperature-dependent thermal conductivity (for mastic asphalt BPGJA-11) which resulted in temperature development curves that correlated well with the results presented in Ellinor Sanned’s bachelor thesis “Insulation of timber with concrete and cast asphalt”. Sanned performed laboratory work were two different samples of mastic asphalt was tested in a cone calorimeter. The cone calorimeter was set to 51 kW/m2 and Sanned measured the temperature development beneath the mastic asphalt. The thermal conductivities for mastic asphalt were, in this master thesis, developed by using inverse calculation in the finite element program TASEF (Temperature Analysis in Structures Exposed to Fire). To form a reliable setup in TASEF, a sensitivity analysis was initially conducted. Information regarding thermal properties of mastic asphalt at elevated temperatures was in general considered challenging to find. Due to this, assumptions of the parameters set in TASEF had to be made. The thermal conductivities were developed at 0 ℃, 300 ℃ and 660 ℃. The results indicates that the thermal conductivity of the mastic asphalt (BPGJA-11) tested by Sanned decreases between 0 ℃ and 300 ℃, and then more or less stabilizes.  The presented thermal conductivities should however be used with great caution. The reason for this is due to uncertainties in the experimental cone calorimeter results, uncertainties within the setup in TASEF as well as within the specific method used. In particular the application on materials which both melts and boils (such as mastic asphalt) should be made with great care. To increase the reliability of the results, more research and laboratory work should therefore be performed within the area.  The method used within this master thesis (inverse calculation using TASEF) is simple and cost effective when determining the thermal conductivity. / Mastic asphalt (som i denna sammanfattning benämns som gjutasfalt) är ett material som i Sverige huvudsakligen används som beläggning för broar, parkeringshus, gårdsplaner och terrasser. Gjutasfalt är ett material som är byggt upp av en kombination av bitumen (en typ av bindemedel), välgraderat stenmaterial (består av både grov och fin ballast), filler, sand och ibland även finmakadam. Gjutasfalt beskrivs som ett material som i Sverige har stor potential att expandera.  Samtidigt blir det alltmer populärt att konstruera byggnader med solida träkonstruktioner. År 2019 analyserades den svenska marknaden för skog och lantbruk, varpå kors-laminerat trä visade sig vara det konstruktionsmaterial som ökar mest i popularitet.  I konstruktioner kan gjutasfalt och trä kombineras. Parkeringshuset Limnologen i Växjö Sverige är ett exempel på en träkonstruktion som kombinerats med gjutasfalt som beläggning. Ett annat exempel är ett enormt parkeringshus i Studen, Schweiz, som har 2142 parkeringsplatser.  Målet med denna masteruppsats var att bestämma den temperaturberoende termiska konduktiviteten (för gjutasfalt BPGJA-11) vilken resulterar i en temperaturutvecklingskurva som korrelerar väl med resultaten presenterade i Ellinor Sanneds examensarbete ”Isolering av trä med betong och gjutasfalt”. Sanned genomförde en laboration där två olika prov av gjutasfalt testades i en konkalorimeter. Konkalorimetern var inställd på 51 kW/m2 och Sanned uppmätte temperaturutvecklingen på undersidan av gjutasfalten.  De termiska konduktiviteterna för gjutasfalt i denna masteruppsats arbetades fram genom ”inversberäkning” i det finita elementprogrammet TASEF (Temperature Analysis in Structures Exposed To Fire). För att bilda en tillförlitlig uppsättning i TASEF, genomfördes inledningsvis en känslighetsanalys. Information gällande termiska egenskaper av gjutasfalt vid förhöjda temperaturer var generellt sätt svåra att finna. För parametrarna som användes i TASEF gjordes därför antaganden.  De termiska konduktiviteterna arbetades fram vid 0 ℃, 300 ℃ and 660 ℃. Resultaten indikerar att den termiska konduktiviteten för den gjutasfalt (BPGJA-11) som testades av Sanned minskar mellan 0 ℃ och 300 ℃, för att därefter mer eller mindre stabiliseras. De termiska konduktiviteterna som har presenteras bör dock användas med stor försiktighet. Anledningen till detta beror på osäkerhet för de resultat som presenterades av Sanned, osäkerheter för uppsättningen i TASEF samt för den specifika metod som används. Speciellt anbefalles försiktighet med att använda metoden för material som både smälter och kokar (såsom gjutasfalt). För att öka resultatens tillförlitlighet bör därför mer forskning och laboratoriearbete utföras inom området. Metoden som har använts inom denna masteruppsats (inversberäkning med TASEF) är enkel och kostnadseffektiv för att bestämma den termiska konduktiviteten.
17

Posouzení nízkohlučného asfaltového koberce mastixového s CRmB / Evaluation of Low Noise Stone Mastix Asphallt with CRmB

Zavřel, Tomáš January 2012 (has links)
The aim of diploma thesis is to design mixture SMA LA 8 with crumb rubber modified bitumen (9,9 %) and a modifier additive TecRoad (22 %) and the test of water sensitivity, the resistance to permanent deformation and to frost cracking, the determination of the stiffness and fatigue characteristics. Test methods are described and evaluated.
18

Etude chimique des matériaux résineux : oliban, dammar et mastic : application à des prélèvements artistiques et archéologiques / Chemical study of resinous materials : olibanum, dammar and mastic : application to artistic and archaeological samples

Aksamija, Amra 21 December 2012 (has links)
Ce travail porte principalement sur l’étude de la partie triterpénique de trois résines végétales naturelles et commercialement disponibles, l’oliban, la dammar et la mastic, par diverses techniques analytiques (IRTF, CLHP/UV, CLHP/UV/Fluorimétrie etCPG-SM). Une étude fluorimétrique a été réalisée sur ces trois résines via réaction de greffage d’un marqueur de fluorescence(chlorure de dansyle), ce qui a permis de détecter les molécules triterpéniques par fluorimétrie, de diminuer leur seuil de détection et d’obtenir une empreinte digitale fluorimétrique spécifique pour chaque résine étudiée. Ce protocole a été appliqué avec succès sur un échantillon archéologique (G14) et le matériel résineux a été identifié (résine oliban, espèce B. frereana). La partie triterpénique a été extraite par divers procédés d’extraction (le reflux, le Soxhlet et les ultrasons) en utilisant trois différents solvants (le méthanol, le n-hexane et le d-limonène) dans le but de déterminer les conditions optimales pour l’extraction et l’identification des molécules triterpéniques par CLHP/UV. Deux colonnes de phase inverse ont été testés dans ce travail : une colonne classique RP-18 (Merck) et une colonne «core-shell» Kinetex (Phenomenex) pour essayer d’optimiser les conditions d’analyse. La colonne Kinetex a permis une diminution de temps d’analyse de 73% pour l’oliban et de 70% pour la dammar et la mastic, ce qui représente un résultat très encourageant. Le protocole optimisé a été appliqué avec succès sur l’échantillon archéologique G12 supposé contenir de la mastic, ce qui a été confirmé par les analyses CLHP/UV et CPG-SM. Une étude quantitative de rendement et d’aire relative du pic a été également réalisée. Les extraits ont été analysés par CLHP/UV etCPG-SM. Pour l’analyse en CPG-SM, la préparation des échantillons a été faite à travers la formation des dérivés TMS(triméthylsilylés) dans le but de créer une base de données de dérivés TMS pour les résines dammar et mastic. L’identification des composés caractérisés dans ce travail a été faite selon la littérature spécialisée, les tR et les spectres UV correspondants. Led-limonène, un solvant «vert», a été utilisé pour la première fois pour l’extraction de ce genre de matériaux, à notre connaissance et il permet une formation directe des dérivés TMS, en présence de solvant d’extraction. Au même temps, sep téchantillons artistiques supposés contenir un vernis à base d’une résine naturelle, en provenance de la Galerie Nationale de Sarajevo (Bosnie-Herzégovine) ont été analysés et seulement pour un de ces sept échantillons, il a été mis en évidence la présence d’une gomme-résine naturelle. L’étude scientifique des échantillons bosniens agrandira la documentation sur l’Art et sur le patrimoine culturel de Bosnie-Herzégovine, qui rencontre une période difficile depuis la dernière guerre (1992-1995) / This work is focused on the study of triterpene part of three natural plant resins commercially available, olibanum(frankincense), dammar and mastic, by various analytical techniques (FTIR, HPLC / UV, HPLC / UV / Fluorimetry and GC -MS). Afluorimetric study was conducted on these three resins via grafting reaction of a fluorescent marker (dansyl chloride), whichallowed to detected triterpene molecules by fluorimetry, decreasing their detection threshold and to obtain a specificfluorimetric fingerprint for each studied resin. This protocol has been successfully applied on an archaeological sample (G14)and the resinous material has been identified (the olibanum resin, the species B. frereana). A triterpenic fraction was extractedby various extraction procedure (reflux, Soxhlet and ultrasounds) using three different solvents (methanol, n-hexane, and dlimonene)in order to determine the optimal conditions for the extraction and identification of triterpenic molecules by HPLC /UV. Two reversed phase columns were tested in this work: a classical column RP-18 (Merck) and column «core-shell» Kinetex(Phenomenex) to try to optimize the analysis conditions. Kinetex column has allowed a reduction of analysis time to 73% foranalyses of olibanum and to 70% for analyses of dammar and mastic resin, and this is a very encouraging result. The optimizedprotocol was successfully applied on the archaeological sample G12, which was supposed to contain mastic resin and thishypothesis was confirmed by HPLC/UV and GC-MS analysis. A quantitative study of performance and the relative area of thepeaks were also performed. The extracts were analyzed by HPLC / UV and GC-MS. Concerning GC-MS analysis, samplepreparation was done through formation of TMS derivatives (trimethylsilyl) with the aim of creating a database of TMSderivatives for dammar and mastic resins. The identification of compounds characterized in this work was done according tothe literature, and corresponding tR et UV spectra. D-limonene, one of «green» solvents, has been used for the first time for theextraction of these materials, according to our knowledge and it allows a direct formation of TMS derivatives in the presence ofextraction solvent. At the same time, seven artistic samples supposed to contain a varnish based on a natural resin from theNational Gallery of Sarajevo (Bosnia and Herzegovina) were analyzed and for only one of these seven samples we found thepresence of a natural gum resin. The scientific study of Bosnian samples expands the scientific documentation in art andcultural heritage of Bosnia and Herzegovina, which encounters a difficult period after the last war (1992-1995)
19

Nové směry v oblasti asfaltových koberců mastixových / New trends in the field of stone mastic asphalts

Pfeiferová, Magdaléna January 2012 (has links)
The work consists of two parts. The first part is focused on the determination of an anti-skid properties of the test section on Vídenská street. The anti-skid properties will be measured using a pendulum tester and macrotexture will be set at the same time. Microtexture will be measured using a volumetric patch technique. In the second part we will try to gain an initial experience with design and testing of a low noise stone mastic asphalt. We will set basic characteristics and at the same time compare with a standard stone mastic asphalt. For the comparison two various bituminous binders are used. The water sensitivity, resistance against rutting and stiffness moduli are compared.
20

Etude chimique des matériaux résineux : oliban, dammar et mastic : application à des prélèvements artistiques et archéologiques

Aksamija, Amra 21 December 2012 (has links) (PDF)
Ce travail porte principalement sur l'étude de la partie triterpénique de trois résines végétales naturelles et commercialement disponibles, l'oliban, la dammar et la mastic, par diverses techniques analytiques (IRTF, CLHP/UV, CLHP/UV/Fluorimétrie etCPG-SM). Une étude fluorimétrique a été réalisée sur ces trois résines via réaction de greffage d'un marqueur de fluorescence(chlorure de dansyle), ce qui a permis de détecter les molécules triterpéniques par fluorimétrie, de diminuer leur seuil de détection et d'obtenir une empreinte digitale fluorimétrique spécifique pour chaque résine étudiée. Ce protocole a été appliqué avec succès sur un échantillon archéologique (G14) et le matériel résineux a été identifié (résine oliban, espèce B. frereana). La partie triterpénique a été extraite par divers procédés d'extraction (le reflux, le Soxhlet et les ultrasons) en utilisant trois différents solvants (le méthanol, le n-hexane et le d-limonène) dans le but de déterminer les conditions optimales pour l'extraction et l'identification des molécules triterpéniques par CLHP/UV. Deux colonnes de phase inverse ont été testés dans ce travail : une colonne classique RP-18 (Merck) et une colonne "core-shell" Kinetex (Phenomenex) pour essayer d'optimiser les conditions d'analyse. La colonne Kinetex a permis une diminution de temps d'analyse de 73% pour l'oliban et de 70% pour la dammar et la mastic, ce qui représente un résultat très encourageant. Le protocole optimisé a été appliqué avec succès sur l'échantillon archéologique G12 supposé contenir de la mastic, ce qui a été confirmé par les analyses CLHP/UV et CPG-SM. Une étude quantitative de rendement et d'aire relative du pic a été également réalisée. Les extraits ont été analysés par CLHP/UV etCPG-SM. Pour l'analyse en CPG-SM, la préparation des échantillons a été faite à travers la formation des dérivés TMS(triméthylsilylés) dans le but de créer une base de données de dérivés TMS pour les résines dammar et mastic. L'identification des composés caractérisés dans ce travail a été faite selon la littérature spécialisée, les tR et les spectres UV correspondants. Led-limonène, un solvant "vert", a été utilisé pour la première fois pour l'extraction de ce genre de matériaux, à notre connaissance et il permet une formation directe des dérivés TMS, en présence de solvant d'extraction. Au même temps, sep téchantillons artistiques supposés contenir un vernis à base d'une résine naturelle, en provenance de la Galerie Nationale de Sarajevo (Bosnie-Herzégovine) ont été analysés et seulement pour un de ces sept échantillons, il a été mis en évidence la présence d'une gomme-résine naturelle. L'étude scientifique des échantillons bosniens agrandira la documentation sur l'Art et sur le patrimoine culturel de Bosnie-Herzégovine, qui rencontre une période difficile depuis la dernière guerre (1992-1995)

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