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Visbys färger : exteriör färgsättning av bostadshus i Visby innerstad 1860–1930 / The colours of Visby : exterior colour schemes of dwellings in the historic centre of Visby 1860–1930Laserna, Max January 2013 (has links)
The main aim of this research is to survey the general colour scheme for private dwellings inVisby, built 1860–1930. During this period the visual appearance of the town of Visby changedsubstantially, since the increased local production of lime led to the plastering of many woodenbuildings. Which colour schemes were chosen for the different building types of the historic centreof Visby, and which colours came to dominate the time period? The methods used for answeringthese questions have partly been field studies on site and sampling of selected buildings, andpartly critical reading and observation of iconographic material (paintings, drawings, aquarelles,postcards and photographs). The field study includes about 45 objects, in which a number ofsamples are taken from each building element (mouldings, plaster, windows and doors). Thesamples were first analysed ocularly as cross sections. A selection of cross sections have then beenanalysed by means of scanning electron microscopy analysis. The results show a unitary colourscheme, based on earth pigment and carbon black. The dwellings erected during the 19th centuryin Visby, represent a significant part of its building stock, and the lack of scientifically groundedresearches makes implementation of adequate maintenance difficult. It also appears that a largenumber of these dwellings have recently been (or are soon to be) restored, causing a serious lossof primary source of information, as well as affecting town and streetscape with new colourings.
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The transverse tensile strength of clay-starch coatings as a function of adhesive distributionEames, Arnold Charles 01 January 1959 (has links)
No description available.
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Archaeometrical Studies On Plasters Of Some Historical BuildingsCiftci, Burcu Devrim 01 February 2007 (has links) (PDF)
The present study aims to investigate the composition of historical plasters to get information about their material characteristics and their technology. Plaster samples were obtained from four Ankara Citadel houses built in late Ottoman period.
In order to determine the raw material characteristics and mineralogical properties of plasters / chemical analyses, optical observation of cross sections, petrographic analyses of thin sections, elemental analyses by ICP-OES, X-ray powder diffraction analyses for the determination of mineral phases, thermogravimetric analyses and FTIR analyses were carried out. Interpretation of all the analytical examination was used to understand the composition and unique character of plaster samples studied.
Observation of thin sections revealed more plaster layers than those observed in cross sections. Up to twelve layers could be observed with different colours, such as blue, red, yellow, green, white and brown.
Generally, thicknesses of white plaster layers were found to be thicker than the others. In two samples, two black boundaries between plaster layers were identified which could be an indication of the use of asphalt for isolation purposes, like dampness proofing or heat insulation. Soluble salt contents of the plaster samples were in the range 3.04%-9.22%, with an average being 6.62%. The anions identified were Cl-, SO42-. In few samples, PO43-, NO2- and NO3- were found. Binder was found to be lime and gypsum. The amount of binder in terms of total calcium oxide, CaO, was found to be in the range of 33.5-43.6%, with an average being 37.9%. Amount of aggregate was about 62.1% as average. The main minerals identified in plaster samples were calcite and gypsum. Gypsum might be added to increase the strength of the plaster. Beside calcite and gypsum, quartz and pozzolanic activity related mineral, Opal-A, were found in some of the samples. In red plaster layers hematite mineral was also identified. Other colour effective elements were found to be Fe, Sb, Mn, Cu, Cr and Ni. Presence of organic additives was observed but clear identification was not established.
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Bio-optical Properties Of The Turkish SeasOrek, Hasan 01 March 2007 (has links) (PDF)
Optical properties of the seas surrounding Turkey (i.e. Mediterranean Sea, Black Sea and Aegean Sea) are investigated utilizing the data collected from years 2001-2005. Pigment, light (irradiance), absorption samples were collected and analyzed. SeaWiFS and MODIS satellite observations between years 1997-2006 has been collected, processed and analyzed. High temporal and spatial variability is observed in the optical properties of the three basins. The Mediterranean Sea and the Black Seas are the two typical examples of the Case I and the Case II waters, respectively. SeaWiFS and MODIS derived chlorophyll data obtained during the time period where the data were coexistent (2002-2004) gave consistent results. Thus, data from both sensors are used to establish temporal continuity. Optical classification of the water types based on the Jerlov model shows that the Mediterranean has clear (Type 1) and very clear water type characteristics and the Black Sea and the Marmara waters are turbid (Type 5). Absorption from yellow substance (or so-called CDOM) does not optically dominate the Mediterranean allowing accurate estimation of pigment concentrations by remote sensing methods. This study is further extended to analyze the main contributing phytoplankton groups to the bio-optical characteristics in the three basins. HPLC measurements show that the diatoms are the main group in the Black Sea ecosystem. Whereas in Mediterranean Cyanophyta dominates. Phytoplankton group compositions in the offshore and coastal regions of the Mediterranean do not show considerable difference. The main differences are the higher Prymnesiophyceae (nearly two times higher then the offshore) and lower Cyanophyta contribution in the coastal regions compared to offshore regions.
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Material Characterization Of Ancient Mural Paintings And Related Base Materials: A Case Study Of Zeugma Archaeological AreaAkyol, Ali Akin 01 September 2009 (has links) (PDF)
In this study, two sample sets from Zeugma Archaeological Area had been
examined. The sample Set I includes 7 sediment, 18 stone, 4 brick/roof tile, 9 mortar,
4 plaster samples and the sample Set II consists of 24 mural painting samples.
Samples were examined to get their raw material characteristics, mineralogical and
chemical compositions, and microstructural properties using various analytical
techniques such as Optical Microscopy, XRD, FTIR, PED-XRF, SEM-EDX and
Raman Spectroscopy. In addition, mikroclimatic monitorings for temperature and
relative humidity were also performed in that area.
Sediments were calcereous soils of Eocene. Rock types of stones were mainly
limestone which had 3 subgroups: micritic, biomicritic and recrytallised micritic
limestones. The source of the limestones should be from the local formation.
The firing temperature of brick/roof tile samples were estimated as 800-850° / C.
Binder of mortar samples were mainly lime.
Aggregate materials of brick/roof tiles, mortars, plasters and mural paintings may
come from the river deposites of Euphrates.
Mural painting samples have one intonaco layer, and single or double arriccio layers.
The mural painting technique was fresco technique.
Calcite was common mineral identified for all pigments. The sources of white, black
and green coloured pigments were found as vaterite, graphite and malachite
respectively. The sources of yellow coloured pigments were identified as ankerite,
siderite and goethite. The red colours were identified as hematite, jasper and red
earth/ochre. Jasper and vaterite, jasper and calcite, red earth/ochre and calcite, and
hematite were the colour forming minerals of pink coloured pigments.
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Contribution à la chimie des flavonoïdes élaboration de squelettes flavylium sophistiqués, nouvelle voie d'accès aux flavan-3-ols et aux proanthocyanidines /Stotz, Marie Brouillard, Raymond. Goeldner, Maurice. January 2008 (has links)
Thèse de doctorat : Chimie organique : Strasbourg 1 : 2008. / Titre provenant de l'écran-titre. Bibliogr. p. 305-321.
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Photopigments as descriptors of phytoplankton assemblages for biotic assessment of Illinois lakes and reservoirs : an HPLC aided analysis /Krenz, Robert J., January 2009 (has links) (PDF)
Thesis (M.S.)--Eastern Illinois University, 2009. / Includes bibliographical references (leaves [117]-125).
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Trophodynamics of the benthic food webs in the Chukchi and Beaufort Seas, AlaskaMcTigue, Nathan David 11 March 2014 (has links)
The Chukchi and Beaufort Sea shelves host diverse and productive seafloor ecosystems important for carbon and nitrogen cycling for the Arctic Ocean. The benthic food web transfers energy from primary producers to high trophic level organisms (e.g., birds, fish, and mammals), which are important for cultural practices and subsistence hunting by Native Alaskans. This work focuses on the trophic ecology of arctic food webs through use of several different approaches. First, variation in the natural abundance of stable carbon and nitrogen isotopes facilitated the identification of trophic pathways and, subsequently, allowed the comparison of trophic guilds and food webs from the Chukchi and Beaufort Seas. Compared to water column and sedimentary organic matter end-members, second trophic level grazers and suspension feeders were conspicuously ¹³C-enriched throughout the Chukchi Sea, which supports the hypothesis that microbial degradation of organic matter occurred prior to metazoan assimilation. Second, food web recovery from disturbances caused by exploratory oil drilling at the seafloor that had occurred approximately 20 years prior were assessed in both the Chukchi and Beaufort Seas. Based on isotopic trophic niche overlap between organisms common to drilled and reference sites in the Chukchi and Beaufort Seas, the oil drilling sites had similar food web structure, indicating recovery from the activity associated with the drilling process. Third, photosynthetic pigment biomarkers were used to better understand the diagenetic process, specifically focusing on how both microbial and metazoan grazing pathways degrade organic matter in relation to seasonal sea ice retreat in the Chukchi Sea. The benthic macrofaunal and microbial food web caused rapid degradation of organic matter upon the initial pulse of microalgal food sources to the seafloor. These diagenetic pathways are linked to the ¹³C-enrichment of residual organic matter, which corresponds to the stable isotope values measured in the benthic macrofauna. Lastly, high-precision liquid chromatography and spectrophotometry were compared for estimating sedimentary pigments in the marine environment. Substantial differences in pheopigment (chlorophyll degradation products) concentrations were observed between the two techniques, suggesting the need for revisions to the monochromatic spectrophotometric equation that relates absorbance to pigment concentrations. One pheopigment, pheophorbide, was found to interfere with the accuracy of the spectrophotometric equation and caused the overestimation of pheopigments. / text
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Εκτίμηση του ποσού των περιεχόμενων φωτοσυνθετικών χρωστικών σε καρπούς με τη χρήση φασμάτων της in vivo ανακλαστικότηταςΚυζερίδου, Αλεξάνδρα 03 May 2010 (has links)
Οι πράσινοι καρποί φέρουν ενεργούς χλωροπλάστες, οι οποίοι επιτελούν φωτοσύνθεση και αναπτύσσονται σε ένα ιδιαίτερο μικροπεριβάλλον, που διαφέρει σημαντικά από αυτό των φύλλων. Συγκεκριμένα, χαρακτηρίζεται από υποξία, πολύ υψηλές συγκεντρώσεις CO2 και χαμηλές εντάσεις φωτός, ιδιαίτερα στα εσώτερα σημεία του καρπού. Οι συνθήκες αυτές διαμορφώνονται από τα ανατομικά χαρακτηριστικά των καρπών και από τον υψηλό μεταβολικό ρυθμό που επιδεικνύουν. Τα ιδιαίτερα χαρακτηριστικά του εσωτερικού του καρπού επηρεάζουν αντίστοιχα τα επίπεδα των συνολικών χλωροφυλλών (Chla+b) και τις σχετικές αναλογίες των φωτοσυνθετικών χρωστικών του (Chla/b, Car/Chla+b).
Στην παρούσα εργασία, το ενδιαφέρον μας εστιάζεται στη μελέτη των φωτοσυνθετικών χρωστικών των καρπών και στη σύγκριση του προτύπου που διαμορφώνεται μεταξύ φύλλων, περικαρπίων και σπερμάτων, σε όσο το δυνατόν περισσότερα φυτικά είδη. Για τον σκοπό αυτό επιλέξαμε να αξιοποιήσουμε τους αντίστοιχους δείκτες της in vivo ανακλαστικότητας (NDI, δείκτης Chla/b και PRI) ως μια γρήγορη, ευαίσθητη και μη καταστρεπτική μέθοδο εκτίμησης των φωτοσυνθετικών χρωστικών. Παράλληλα, θέλοντας να ελέγξουμε την αξιοπιστία των ανωτέρω δεικτών ανακλαστικότητας και στους καρπούς, προσδιορίσαμε τα επίπεδα των φωτοσυνθετικών χρωστικών και των σχετικών αναλογιών τους και με την παραδοσιακή μέθοδο της εκχύλισης-φασματοφωτομέτρησης.
Τα αποτελέσματά μας έδειξαν ότι σε όλες τις περιπτώσεις, τα περικάρπια περιέχουν σαφώς λιγότερες συνολικές χλωροφύλλες και ακολουθούν τα σπέρματα με ακόμα λιγότερες. Η σχετική αναλογία Chla/b είναι χαμηλότερη στα περικάρπια και τα σπέρματα έναντι των φύλλων, γεγονός που μπορεί εν μέρει να ερμηνευθεί ως σκιόφιλη προσαρμογή (περίπτωση σπερμάτων). Ωστόσο, οι εξωτερικές (πλήρως φωτιζόμενες) και οι εσωτερικές (σκιαζόμενες) πλευρές των περικαρπίων εμφανίζουν ίδια επίπεδα του λόγου Chla/b στα περισσότερα είδη που μελετήθηκαν. Αυτό μας υποδεικνύει ότι, ενδεχομένως, άλλοι παράγοντες πέραν του φωτός επηρεάζουν τη σχετική αναλογία των δύο χλωροφυλλών. Επιπρόσθετα, παρατηρήθηκε μη αναμενόμενη, αυξημένη σχετική αναλογία των συνολικών καροτενοειδών σε σχέση με τις συνολικές χλωροφύλλες (Car/Chla+b) των περικαρπίων και των σπερμάτων έναντι των αντίστοιχων φύλλων, εύρημα που χρήζει επίσης περαιτέρω μελέτης. / Green fruits contain active chloroplasts, which are driving the reactions of photosynthesis and function in a particular microenvironment, completely different from that of leaves. This microenvironment is characterized by hypoxia, extremely high internal CO2 concentrations and low light intensity, especially in the inner part of the fruit. The above conditions are shaped by fruit anatomical features and their high metabolic rhythm. The special characteristics of the fruit’s internal affect the total chlorophyll concentration (Chla+b), the ratio of Chla to Chlb (Chla/b) and the carotenoid to chlorophylls ratio (Car/Chla+b).
In this study, the photosynthetic pigment profile of green fruits (pericarps and seeds) of 15 different species was investigated, with the corresponding leaves serving as controls. To this aim, the appropriate in vivo spectral reflectance indices (NDI, Chla/b index and PRI) were used, as a rapid, sensitive and non-destructive method for photosynthetic pigment estimation. In order to assess the reliability of the above indices in fruits, we estimated in parallel the photosynthetic pigment levels and their ratios with traditional extracting methods.
Our results indicated that compared to leaves, pericarps are characterized by lower levels of total chlorophylls followed by seeds with even lower. The Chla/b ratio is lower in pericarps and seeds. As a consequence the lower Chla/b ratio could only partly be attributed to a shade adaptation. However, the exposed and shaded sides of pericarps displayed similar values for Chla/b ratio in the most of the species tested. Moreover, pericarps and seeds showed unexpectedly, higher carotenoid/chlorophyll ratios.
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Probing molecular tracers in geobiological systems using imaging mass spectrometryLeefmann, Tim 11 April 2013 (has links)
No description available.
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