Search results for "pigments."
showing 10 items of 133 documents
Identification of plant cells in black pigments of prehistoric Spanish Levantine rock art by means of a multi-analytical approach. A new method for s…
2017
We present a new multi-analytical approach to the characterization of black pigments in Spanish Levantine rock art. This new protocol seeks to identify the raw materials that were used, as well as reconstruct the different technical gestures and decision-making processes involved in the obtaining of these black pigments. For the first of these goals, the pictorial mat- ter of the black figurative motifs documented at the Les Dogues rock art shelter (Ares del Maestre, Castello ́ n, Spain) was characterized through the combination of physicochemical and archeobotanical analyses. During the first stage of our research protocol, in situ and non- destructive analyses were carried out by means of…
Лабораторные химико-препаративные упражнения: методы получения промежуточных продуктов искусственных органических пигментов из исходных материалов
1907
Uz vāka izdošanas gads: 1908.
Sicilian Byzantine Icons through the Use of Non-Invasive Imaging Techniques and Optical Spectroscopy: The Case of the Madonna dell’Elemosina
2021
The iconographic heritage is one of the treasures of Byzantine art that have enriched the south of Italy, and Sicily in particular, since the early 16th century. In this work, the investigations of a Sicilian Icon of Greek-Byzantine origin, the Madonna dell’Elemosina, is reported for the first time. The study was carried out using mainly non-invasive imaging techniques (photography in reflectance and grazing visible light, UV fluorescence, infrared reflectography, radiography, and computed tomography) and spectroscopic techniques (X-ray fluorescence and infrared spectroscopy). The identification of the constituent materials provides a decisive contribution to the correct historical and arti…
Carotenoids and Color of Fruit Juice and Milk Beverage Mixtures
2007
Seventeen commercially available, "ready to drink" fortified beverages consisting of mixtures of fruit juices and milk were analyzed to evaluate their carotenoid profile (including their Z/E stereoisomers) and color during their commercial shelf life. Lightness (L*) was found to be correlated with the content of milk in the mixtures (r= 0.649) whereas red-yellow colors were correlated with the contents of alpha-carotene, beta-cryptoxanthin, and beta-carotene supplied by the fruit. The beverages stored under refrigeration (4 +/- 2 degrees C) showed higher luminosity (L*) and higher saturation of color (C*) and yellowness (b*). Differences (P < 0.05) in the levels of carotenoids were found am…
"Historical pigments characterisation by quantitative X-ray fluorescence"
2014
Abstract Most of the historical paints are mainly constituted by inorganic pigments, either pure or mixed, spread on the surfaces using different binding agents. The knowledge of the exact amount of different constituents of the paint, as well as of the mixing and pictorial techniques, is crucial for a careful program of conservation of polychrome works. Moreover, since the availability of these pigments has been changing through the centuries, their identification and chemical characterisation is useful to acquire or deepen information about the artist and his/her work. This information can also be useful for authentication purposes through relative dating because the identification of one…
Colours of the « images of the floating world ». non-invasive analyses of Japanese ukiyo-e woodblock prints (18th and 19th centuries) and new contrib…
2019
Abstract In the Edo (1615–1868) and Meiji (1868–1912) periods, Japanese woodblock prints were a commercial form of art that reproduced the everyday life of ordinary people (the ukiyo-e style). Since different dyes and pigments were used to produce these prints, changing over time, the knowledge of these materials can be very important for the history and the conservation of ukiyo-e prints. This study will present the results of the investigation of several woodblock prints, produced between the 18th and 19th centuries. The artworks belong to the Asian art collection at the Museum of Zaragoza (Spain). The aim of the study is the identification of organic colorants and inorganic pigments empl…
Human NCL Neuropathology
2015
AbstractThe neuronal ceroid lipofuscinoses (NCL) currently encompass fourteen genetically different forms, CLN1 to CLN14, but are all morphologically marked by loss of nerve cells, particularly in the cerebral and cerebellar cortices, and the cerebral and extracerebral formation of lipopigments. These lipopigments show distinct ultrastructural patterns, i.e., granular, curvilinear/rectilinear and fingerprint profiles. They contain−although to a different degree among the different CLN forms−subunit C of ATP synthase, saposins A and D, and beta-amyloid proteins. Extracerebral pathology, apart from lipopigment formation, which provides diagnostic information, is scant or non-existent. The ret…
Retina in various animal models of neuronal ceroid-lipofuscinosis
1992
The childhood forms of human neuronal ceroid-lipofuscinosis (NCL) are invariably associated with a severe progressive retinopathy which commences at the photoreceptor level morphologically and proceeds to a final loss of neuronal cells accompanied by severe gliosis. In respective spontaneous animal conditions of NCL, in English setters, Dalmatian dogs, and New Zealand sheep, retinal involvement is not commensurate although the retina does not seem to be completely unaffected. In canine NCL, there might be functional and electro-physiological impairment of retinal cells, but retinal atrophy is not obvious. In ovine NCL, the retina, apart from accumulating NCL-specific lipopigments within neu…
Differential response of benthic microbes and meiofauna to fish-farm disturbance in coastal sediments
2001
Bacterial and meiofaunal abundance and biomass and their response to the disturbance induced by fish-farm biodeposition were investigated from March to October 1997 on a monthly basis at two stations of the Gaeta Gulf (Tyrrhenian Sea, Mediterranean Sea). The biopolymeric fraction of the organic matter was characterized by high concentrations which was similar at both fish-farming-impacted and control stations. Similarly, bacteria accounted for a small fraction of the biopolymeric organic carbon (<1%), while the contribution due to auto-fluorescent cell biomass (i.e. prokaryotic and eukaryotic cells displaying auto-fluorescence) to the total biopolymeric carbon was quantitatively negligible …
Indoor lighting quality: Effects of different wall colours
2016
This paper reports the results of measurements performed in a test room to investigate the impact of using different wall colours and light scenes on indoor lighting quality. Eye level spectral irradiances were measured for a user located inside the room and seated at a desk. These measurements allow the use of the Irradiance Toolbox, which makes it possible to calculate equivalent illuminances for the photopigments in the human eye. Moreover, the CIECAM02 colour appearance model was used to investigate the variations in hue and chroma values of the different wall colours when changing the light scene. The results demonstrate that there are significant variations in eye level spectral irra…