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1.
Using inductively coupled plasma–atomic emission spectrometry (ICP-AES), atomic absorption spectrometry (AAS) and instrumental neutron activation analysis (INAA) the concentration of Ag, As, Au, Bi, Cu, Fe, Ga, In, Ni, Sb, Sn, and Zn in 53 samples taken from archaeological finds dated to 4th–2nd century BC and found in the territory of ancient Thracia was determined. Additionally using inductively coupled plasma–mass spectrometry (ICP-MS) and MS for determination of the lead isotope ratios in the samples was carried out. On the basis of these analytical results using cluster analysis for grouping the samples on the bases of the similarity in chemical and isotopic content and the available data from the literature for lead ore deposits in the Balkan Peninsula, the geological origin of the investigated archaeological finds was evaluated. That confirms the expectation that sources of lead might be almost all possible deposits of lead ores on the Balkan Peninsula—from Lavrion through Chalkidiki to the Rhodope mountain. The result indicates that the Thrace did not utilize one single lead source continuously but that lead was provided according to availability from different production centers.  相似文献   

2.
During the 13th and 14th centuries, the commune of Massa Marittima successfully exploited the nearby base-metal mines (copper, lead and silver). Several smelting sites were active. Twenty-seven slag specimens were sampled at Marsiliana, Arialla and Rocchette Pannocchieschi. Slags have been analysed by X-ray fluorescence spectrometry, X-ray powder diffraction, optical microscopy, scanning electron microscopy and energy dispersive X-ray spectrometry. The slags from the three sites differ in chemical composition. The most abundant pyrometallurgic phases in the glassy matrix are calcic clinopyroxene, kirschsteinite, melilite, accompanied by spinel, wüstite, sulphides, metals and metal alloys. The three sites produced more than 2000 t of copper, 6000 t of lead and 2 t of silver. Copper was mostly smelted at Marsiliana, and silver-bearing lead was smelted at Arialla and Rocchette Pannocchieschi. The minerals underwent only a mild roasting prior to smelting. Flux lime was added to the mineral charge, and the resulting viscosity index of the melts (from 0.9 to 3.7) assured effective metal segregation. Furnace temperatures reached 1150–1300 °C.  相似文献   

3.
A significant number of archaeological finds of the 13th–16th century from the Tuscan sites of Germagnana and Gambassi in Valdelsa—FI, was studied by different physico-chemical investigations (SEM–EDS, ICP, Mössbauer spectroscopy, XRD, XRF, TG-DTA) in order to contribute to clarify the production methodology and the pre-industrial glass manufacture technology. The studied samples are mainly non-vitreous finds as production waste, refractory materials, crucibles and raw materials; also vitreous finds as frits, skims, glasses (glass masses, glass working waste and finished products) have been taken into consideration. The obtained petrographic and physico-chemical data strongly suggest that both Gambassi and Germagnana glass manufactures were strictly connected with the sources of vitrifiable materials, situated in Tuscan sand quarries. In particular a comparison between sands from the neighbouring quarries and appropriate finds of the two archaeological sites evidences that the employed vitrifiable materials possibly belong to La Casina La Cava resort. The archaeological classification, based on macroscopic observation and stratigraphic position, was compared and verified with the scientific classification of the examined finds of Germagnana and Gambassi sites based on their composition, morphology and physico-chemical properties.  相似文献   

4.
The paper conducts a statistical analysis of the dynamics of the sale of new music (product differentiation innovation) in the record industry. In pursuing this goal the paper generates new data and analyses a previously unutilized data set. The paper finds that there is a strong correlation between new music innovation in the audio singles and albums market. This is found to be mainly concurrent in the same quarter and to have a reasonably short product life. The paper discovers that these features also characterise the dynamics of record company performance. The research indicates that record companies are willing to sell singles at a loss due to advertising rather than learning externalities. At the industry level, the paper finds that new music innovation does not effect market size significantly and mainly causes business stealing effects between record companies, with exceptional cases of multiplier effects.  相似文献   

5.
This study considers the Australian DVD industry using a data set of retail sales for over 44,800 titles 1997–2007. A sub-sample of 760 titles which also received an initial theatrical release reveals that the DVD revenue distribution has thicker tails than the theatrical revenue distribution implying the top-ranked DVDs earning a greater share of revenues than their theatrical contemporaries. A comparison of revenues finds not only a high degree of correlation between the two markets, but a relationship that is nonlinear and increasing at higher theatrical revenue levels. This finding is consistent with a word-of-mouth momentum effect and more institutional flexibility in the DVD market. The high levels of correlation are present across all genres/ratings and are observed to be stronger for large release titles. Finally, a seemingly unrelated regression structure is proposed to jointly consider the two markets, which is shown to be empirically valid.  相似文献   

6.
Structure and organization seems to be at the root of many of the questions raised about institutional behaviour; however, with respect to research on university capacity building, few studies have examined research organizational problems, particularly in developing countries. This study investigates academic reactions to the structure and organization of research at four leading Vietnamese universities. Through document analysis and semi-structured interviews with 55 participants, the study finds that the four case-study Vietnamese universities have accomplished a number of the more visible tasks of research management such as creating research and research management positions; deciding primary organizational units for research delivery; creating a research office; and creating research oversight committees. However, they seem to neglect the other less visible tasks of organizing and structuring research such as developing rules for research integrity; developing a mechanism for evaluating the quality of research outcomes; preparing researchers and research managers for the necessary skills and knowledge; and deciding vertical and horizontal decentralization. The study concludes that even though research has been formally structured and organized, the management of research has not yet been professionalized. The key problem in organizing and structuring research is the lack of an effective system for research behaviour formalization. A more effective system for better formalizing research behaviours should be developed so that Vietnamese universities can integrate more successfully into the global research.  相似文献   

7.
The oil painting “La Medusa” executed by Caravaggio at the end of the XVI century on a wooden shield, was investigated by integrated physical–chemical and analytical methodologies in order to obtain scientific data capable of elucidating the state of conservation and the painting technique. Optical (OM) and electronic (SEM-EDS) microscopy, micro-FT-IR spectroscopy, gas chromatography–mass spectrometry (GC–MS) and pyrolysis GC–MS were applied on two microfragments and some organic samples obtained by solvent extraction using the swab cleaning technique. The obtained results indicated that Caravaggio probably reused an old shield as a previous gypsum preparation layer has been detected under the original painting layers. He used white lead, natural earths, verdigris and lead–tin yellow type I mixed with drying oils to paint. The considerable amount of amorphous particles of copper chlorides found in the green pigment verdigris suggests that it could have been produced according to the ancient recipe of verde salsum described by Theophilus. Mordant gilding has been identified on the upper part of the shield that can be related to an abandoned experiment to give the painting a mirror-like reflecting effect. Three different varnishes layers have been detected above the painted surface. The original and restoration varnishes have been identified and they contain a mixture of drying oil, mastic and turpentine and some beeswax. Cleaning tests, performed with different organic solvents, suggest the use of isopropyl alcohol as cleaning agent because it is less efficient in comparison to others solvents; thus it ensures a careful and controlled removal of the varnishes.  相似文献   

8.
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9.
Biodeterioration of Incralac used for the protection of bronze monuments   总被引：2，自引：0，他引：2  
Outdoor bronze sculptures are highly susceptible to corrosion in many environments and organic coatings are widely used for their protection. The purpose of this study was to determine the susceptibility of the commonly used coating Incralac to biodeterioration by microorganisms. A yeast was isolated from a bronze statue treated with Incralac and its ability to degrade Incralac was determined using growth curves, scanning electron microscopy (SEM), and electrochemical impedance spectroscopy (EIS). The organism grew slowly on Incralac in liquid culture, but SEM images demonstrated its ability to adhere to Incralac coated metal. Additionally, the yeast caused a rapid drop in the low frequency impedance of Incralac coated metal that was not observed under sterile conditions, indicating that the organism accelerated deterioration of the coating. The potential for microbial growth to accelerate deterioration of Incralac should be considered when developing a maintenance strategy for the protection of outdoor metal monuments.  相似文献   

10.
The literature of cultural economics generally finds that an artistic education has no significant impact on artists’ income and careers in the arts. In artists’ labor markets, indefinable features such as talent and artistic creativity apparently contribute more to success or higher rates of payment than education and training. In this article, we will readdress this question by looking at the artists’ survival in the arts occupations. We find it reasonable to expect than an artistic education can have a significant impact on artists’ careers because of the importance of technical skills, networks and signaling effects. We analyze the question by using a unique longitudinal dataset for five different groups of artists in Denmark, using the Cox model to apply survival functions and semi-parametric analysis. The results show, among other things, that an artistic education has a significant impact on artists’ careers in the arts, and we find important industry differences.  相似文献   

11.
Acetic and formic acid vapors emitted from woodwork in historical organs are very important corrosive agents for lead pipes. These acids are slowly released from the wood both during playing and when the pipes are silent. To inhibit this emission process, the wood surface can be modified, by creating a protective layer with alkaline features. However, a coating of wood is not recommended since this could modify the appearance and create a layer not perfectly compatible with the substrate. For this reason, we propose to use some innovative nanotechnology that has been successfully applied for the deacidification of wood samples coming from the Vasa shipwreck. Application of calcium (or magnesium) hydroxide nanoparticles, with sizes ranging from 30–150 nm, allowed a homogeneous distribution of particles through the surface layer of wood simply by soaking (or spraying) it in a alcoholic (or mixed with less polar solvents) dispersion of nanoparticles. Nanoparticles do not modify the wood appearance and distribute randomly within the first layers of wood. The small size of particles accounts for the high reactivity with CO2 from the air, to give the alkaline reserve of carbonates that provide high efficacy in the neutralization of gaseous acids. The emission of volatile organic compounds (VOC) from the treated wood was determined by using an emission test cell, Field and Laboratory Emission Cell (FLEC). The results show that the emissions of acetic acid vapor from nanoparticles treated wood was very low (< 70 μg/m2 h) during the first 13 month. In contrast, untreated wood emitted high concentrations of acetic acid vapor (200–400 μg/m2 h).  相似文献   

12.
The pigments, organic materials and techniques used on a post-Byzantine icon of St Nicholas were determined by means of several micro-analytical techniques. The icon painter covered the leather support with silver leaf about 3 μm thick to create a smooth working surface. Animal glue was used to secure the leaf to the leather, and FTIR spectroscopy has identified another layer, 30–60 μm thick, of the same material applied as a primer above the silver. Above that, a layer of lead white covering the entire surface creates a white substratum serving the same purpose as the gesso on a wood panel. The colour palette, determined by means of scanning electron microscopy and FTIR spectroscopy, is very simple. Only seven colours were identified: lead white, caput mortuum, red and yellow ochre, cinnabar, carbon black and smalt. As far as we know, this is the first time that smalt has been found on a Byzantine icon. Since smalt was chemically synthesised only after 1500 AD, it may be concluded that this icon was painted after the end of the 15th century. Beeswax was used as a protective varnish.  相似文献   

13.
During the restoration plan of the famous painting “Madonna col Bambino e S. Giovannino” by Sandro Botticelli, located in the Museo Civico of Piacenza (Italy), a study on painting materials was carried out. The pigments, the binders and the materials used for the application of ground and priming layers were studied using micro-Raman spectroscopy, gas chromatography coupled with mass spectrometry (GC/MS), optical and electronic microscopies. Gypsum and anhydrite were found in the ground layer, while carbon black and lead white were used in the priming layers. The precious pigments of the artist's palette and the binders used (egg and animal glue) were determined.  相似文献   

14.
Along the Umbria-Marche stretch of the Flaminia Consular Road (220 B.C.) several archaeological finds of the most important monumental works, are well preserved. The stones, employed to build many bridges, substructions and sewerages, are represented by carbonatic breccias whose geological environment of formation and source areas had never been established. On the basis of mineralogical, petrographic and micropalaeontological analyses, two groups of these lithotypes employed in Roman age were distinguished: “monogenic carbonatic breccias” only constituted by clasts of the Maiolica Unit (Late Jurassic – Early Cretaceous) and “polygenic carbonatic breccias” made of fragments (in different proportions) of Calcare Massiccio (Early Jurassic), Corniola (Early Jurassic), Maiolica (Late Jurassic – Early Cretaceous) and Scaglia Rossa (Late Cretaceous – Early Paleogene) Units. The possible source areas of the breccias are compatible with stratified slope-waste to scarp-base deposits of periglacial origin belonging to the Upper Pleistocene. In particular, among the seven investigated areas, we pointed out the most probable provenances (Monte Faeto-Colle, Costacciaro, Scirca, Foci, Secchiano) along the flanks of the Apennine Mesozoic chain of the Umbria and Marche regions. Although the Romans could have exploited the whole thickness of some outcrops (now disappeared) of these carbonatic lithotypes at the deepest part of the valleys, we have constrained a local provenance of the breccias so commonly used in the monumental works of the Flaminia.  相似文献   

15.
Abstract

Global perspectives and national approaches have dominated studies of climate-change communication, reflecting the global nature of climate change as well as the traditional research focus on national media systems. In the absence of a global public sphere, however, transnational issue attention is largely dependent on regional media systems, yet the role this regional dimension plays has been largely overlooked. This article presents a comparative study of climate-change coverage in three geo-cultural regions, The Middle East, Scandinavia, and North America, and explores the link between global climate-change communication and regional media systems. It finds that regional variations in climate-change communication carry important communicative implications concerning perceptions of climate change's relevance and urgency.  相似文献   

16.
Within the framework of an excavation project aimed to systematically characterize the various aspects of settlement and activities in Northern Jordan, a considerable collection of slag lumps and iron artifacts of different forms and typologies excavated from the archaeological site of Barsinia were collected. Excavations have revealed other metallurgical materials such as pottery tuyeres and furnace-like structure. Studying those finds was important because of their archaeological and technological interests. For the analytical and metallurgical study, X-ray diffraction was used to identify the mineralogical composition of samples. Inductively coupled plasma-optical emission spectrometer, energy dispersive X-ray and X-ray fluorescence spectrometer were used to determine the accurate elemental composition of these finds. Furthermore examinations by using metallographic, polarizing microscope and scanning electron microscopy were employed to diagnose the characteristic morphology and environmental effects of these archaeometallurgical finds. Microstructural investigations emphasized that iron production processes were performed locally at the archaeological site of Barsinia even if the iron ores were imported from other mining location in Jordan. Direct or “bloomer” was the main method used for smelting iron ores followed by smithing methods to locally produce iron artifacts. This, most probably, was the state of technology from the Bronze Age to the Byzantine period. To ensure the stability of these deteriorated finds for future research, required treatment and conservation processes were successfully carried out.  相似文献   

17.
The protection against graffiti has become a serious problem in most cities. Unfortunately such form of vandalism does not save the cultural heritage. The use of anti-graffiti coatings is a common treatment that can also temporary protect the surface from degradation due to interactions with the environment. Aspects that have not yet been sufficiently investigated from a metal artefact perspective are whether the presence of the anti-graffiti coating will influence the patina composition and reduce the degree of patina dissolution. Long-term (four years) effects of wax-based anti-graffiti coatings on bare copper sheet and pre-patinated copper exposed to urban atmospheric conditions are presented and discussed in terms of changes in patina dissolution rates, barrier properties and composition. The investigation is based on a multi-analytical approach combining chemical analysis, analytical and electrochemical tools (stereomicroscopy, FTIR, XRD, SEM/EDS, AAS, EIS, colorimetric measurements). Results are believed to provide important information related to the long-term applicability of such coatings to preserve the Cultural Heritage.  相似文献   

18.
This article reports the first occurrence of the combined use of lead and tin yellow type I and type II identified on the same paint layer. The two forms have been identified by Raman microscopy on a green layer from the background of the painting Gonfalone della Giustizia (confraternity of Justice banner) executed at Perugia around 1496 by Pietro Perugino.  相似文献   

19.
The paper is concerned with the issue of whether international copyright legislation is effective in curbing audio software counterfeiting. The paper finds that copyright conventions have not been effective in reducing audio counterfeiting to comparatively low levels. This result holds even when allowances are made for the duration of copyright convention membership and the specificity of the articles of the convention. Economic development is found to be the main determinant of low counterfeit levels. This would tend to support anecdotal evidence which indicates that economic development is a necessary condition for the active recognition of audio property rights by the general public, judiciary and police. It is also consistent with a view that pirate audio software, being an inferior good, has a more buoyant market in less developed economies. From a policy perspective the research would seem to suggest that the extensive efforts and copious attention to detail by legal experts has made little impact on counterfeit activity and is secondary in importance to the socio-economic environment in which these laws are being applied.  相似文献   

20.
In 1990, the Act governing theUnited States' National Endowment for the Arts wasamended requiring the Chairperson to ensure thatjudges of grant applications should take intoconsideration ``general standards of decency andrespect for the diverse beliefs and values of theAmerican public'. This provision has been widelydebated, and was challenged on the basis of whether itviolated the right of freedom of expression. But arecent decision by the U.S. Supreme Court found theprovision to be constitutional. This paper examinesrationales that have been put forward by philosophicalliberals, economists, and communitarians in support ofpublic funding of the arts. It finds that for each ofthese rationales the decency-and-respect provision onfunding is justifiable. The paper concludes with aspeculative discussion of the economics of the``artworld'.  相似文献   

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