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1.
The costs for deterioration and soiling of different materials due to air pollution are huge and the damage to culture targets endangers seriously the rich European cultural heritage. Within the sixth Framework Programme of the EU, the overall aim of the CULT-STRAT project has been to assess and predict the effects of different pollutants on materials and objects of cultural heritage in a multipollutant scenario and to identify indicators and thresholds levels of pollutants. In particular, the present paper reports one of the studies carried out in the CULT-STRAT project at city level and focused on the town of Madrid (Spain). Different maps are shown for the past, present and possible future scenarios: inventory of stock of cultural heritage for each selected material, concentration of selected pollutants (SO2, NO2, O3 and PM10), corrosion (cast bronze) and recession (Portland limestone), exceedance of tolerable degradation thresholds for each material and corrosion-cultural heritage overlapped maps. The model and the methodology developed could be useful if apply it to towns, regions or countries in order to quantify the percentage of Cultural Heritage at risk or to quantify the percentage of the area where corrosion/recession exceeds the established tolerable levels.  相似文献   

2.
In this study, passive samplers were used to measure ozone exposure distribution maps over the historical peninsula of Istanbul, Turkey. The study area is partially important due to the presence of cultural and historical buildings and structures distributed all over the peninsula. Unesco's World Heritage list covers four zones located in this historical peninsula in Istanbul. It is necessary to evaluate the pollution distribution in high resolution to construct effective risk management strategies. For this purpose, 50 sampling stations were installed within the study area. Three sampling campaigns within different seasons (summer, winter and fall) showing different ozone distribution characteristics were carried out. Seasonal measurements of ozone exposure values were used to obtain a yearly exposure level, which is an important part of risk characterization. Seasonal ozone exposure maps over the historical peninsula were obtained using Geographical Information Systems (GIS) based interpolation models with high resolution. Risk maps including five regions, based on ozone exposure levels were created. Structures and historical regions located within these risk zones were identified. Based on the defined exposure regions, we found that the Archaeological Park, one of the items on UNESCO's list, is located within the most risky region.  相似文献   

3.
Several climate parameters affect the growth of organisms and, hence, their capacity to accumulate biomass. In the present research, we analyse the influence of two parameters, temperature and precipitation, on biomass accumulation on stone substrate, and propose a function to estimate it in temperate areas. The expression is subsequently used for the first time to evaluate the impact that climate change would have in biomass accumulation in Europe. The models on climate change predict an increase in temperature and precipitation in northern areas of Europe for the far future (2070–2099), which would lead to a higher accumulation of biomass. Otherwise, a significant reduction in precipitation is expected in southern areas of Europe, associated with a lower biomass accumulation in such areas.  相似文献   

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Electrochemical realkalisation is a technique aimed at stopping rebar corrosion in carbonated concrete. The alkalinity of the concrete around the rebars is restored, and an environment favourable to the passivation of steel is re-created. The technique is based on the application of a DC current from an anode, placed on the external surface of the concrete, and the rebar. The anode is usually embedded in cellulose pulp soaked with a solution of sodium or potassium carbonate. The rebar and the anode are connected to a DC current feeder, the rebar to the negative terminal and the anode to the positive terminal. The applied current produces alkalinity at the surface of the rebar, while the alkaline electrolyte in which the anode is immersed penetrates from the external surface. In this way the concrete is realkalised, its protective characteristics towards the steel are restored and rebars can return to passive conditions. The treatment is temporary: this feature makes it very attractive in the field of historical buildings and cultural heritage, where the conservation of the original materials and surfaces is often a stringent requirement in the design of the repair. This paper shows the advantages of this technique applied to historical structures by describing the application to a bell tower built in the 1920s. The electrochemical realkalisation treatment was applied to eight columns on the bell tower where a traditional repair (based on the substitution of carbonated concrete with a repair mortar) would have been practically impossible. The application of the treatment followed two steps: initially, a trial was made on two sections of two columns, so as to calibrate the process parameters such as current density, time length and type of anode. Subsequently, the treatment was applied to all the columns. The analyses carried out on the concrete after the application of the treatment showed that the protection to the reinforcement was mainly connected to the alkaline layer produced around the steel, which is expected to prevent further corrosion of the steel.  相似文献   

6.
The impact of lighting, heating and people in re-using historical buildings are discussed for the case study concerning the ceremony room (i.e. the Giant Hall) of a mediaeval palace in Padova. The Hall has substantially four major problems for conservation: (i) the impact of heating, lighting and people when the room is used; (ii) many cracks on the oak panels of the coffered ceiling; (iii) the soiling by dust and soot particles deposited on the frescoes; (iv) the stained glass windows. A microclimate study was performed to know the impact of the environmental variables, and the use of the room, on the artworks preserved inside. The study has proved the impact of the lamps (both incandescence and compact fluorescent lamps) on the ceiling, the penetration of external air in the room, the heat and the moisture released by people, the impact of sunshine through windows and the scatter diagram of the daily cycles in temperature (T) and relative humidity (RH). During winter concerts, the strips of lead which are wrapped round the edge of the cut glass pieces in stained glass windows easily drop below the dew point and form condensation, starting corrosion. A discussion concerns the allowed variability, which should not exceed risk thresholds. A safe interval can be established within the area determined by the most frequent T and RH natural cycles. In fact, both of the cycles were compatible with the artefacts, or the artefacts were already damaged to allow the exceeding dimensional changes. Attention should be paid in the variability external to this area, especially approaching or exceeding a limit equal to twice the mode of the natural variability.  相似文献   

7.
The reliable identification of proteinaceous binders in historical mortars and plasters represents a complicated analytical problem. In this paper the possibility of peptide mass mapping (PMM) in connection with the mass spectrometry is demonstrated. The presence of milk and collagen proteins was trustworthy proved in the samples of mortars taken from the Romanesque rotunda of Saint Catherine in Znojmo (Czech Republic).  相似文献   

8.
历史文化名村名镇建设除了景观保护与建设外,还应关注名村名镇的声景营造。声景营造对当地历史文化的传承保护有着特殊的作用和意义。声景大致分为自然声景和社会人文声景。对社会人文声景的主要层面、现状以及创新实践手段进行探讨,归纳出历史文化名镇名村声景营造的可行路径。  相似文献   

9.
The ablation of biofilms by excimer laser radiation was systematically examined in a series of model studies during which the biofilms originating from different historical panels were simulated on model glasses. The composition of these model glasses was modelled on that of the original historical glasses. Our studies have shown that glass composition, climatic conditions and biofilm formation are factors which interact synergetically. It could be observed that various biofilms grow differently on the same type of model glass and that the same type of biofilm shows a different development on various model glasses. The decisive factors for the effectiveness of biofilm ablation by laser irradiation is the formation of the biofilm on the one hand and its corrosive potential on account of its ability to accumulate moisture and to produce glass-damaging metabolites on the other. Glasses of low chemical stability promote the growth of dense biofilms and can be cleaned only with a high energy density, whereas glasses of high chemical stability merely allow for a slow growth of a biofilm spreading two-dimensionally on the glass surface which can be gently removed using low energy density.  相似文献   

10.
In many historical and monumental Italian buildings, frescoes or stuccoes of artistic and historical value are present on the lower surface of flat light vaults, made by wooden arches, reeds and plaster. These vaults are often suspended by wooden or metallic ties to the upper bearing structures. When differential settlements of the wooden arches happen (i.e.: due to a bad working of their hangings) cracks appear on these precious surfaces. This paper experimentally and numerically investigates on this issue, pointing out which constructive parameters mainly influence the cracking behaviour of the frescoed or stuccoed lower surface, and thus providing guide lines for designing compatible conservation and retrofitting interventions.  相似文献   

11.
This note of research argues that Reitlinger's series, and all other series such as Meyer's which are based on official auction sales reports, suffer from significant distortions. This distortion is caused by two main factors: a) the absence of data relating to the identity and the profession of the market agents involved in the transactions recorded in time series; b) the criteria of selection adopted to construct the historical series of prices.  相似文献   

12.
This research focuses on the characterization of historical mortars collected from a covered dockyard, called tezone 105, erected in the Arsenal of Venice during the XVI century. The mortars date back to different building phases. A stratigraphical analysis of tezone 105 has proposed a chronology of building interventions. The building phases recognized by the stratigraphical analysis belong to the original structure (XVI century) and to later interventions from XVI to XX century. Mortar samples are investigated by granulometric analysis, infrared spectroscopy (FT-IR), simultaneous thermal analysis (DSC/TG) and X-ray diffraction analysis (XRD) in order to identify the technology peculiar of each building phase. Mortar sampling was carried out on indoor masonry and foundation. Masonry mortars appeared to be characterized by the application of air-hardening binders, whereas foundation mortars were characterized by hydraulic binders.  相似文献   

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ABSTRACT

As financial transactions are increasingly digitized, old and new kinds of intermediaries are only expanding in importance. Intermediaries, mediators and brokers sit at critical junctures and operate between diverse financial arenas and pathways. We argue that mapping the intermediate entails identifying how different kinds of actors—human and non-human, objects and interfaces, institutions and practices—delimit or reify but also stitch together and overcome spatial and temporal differences in people's financial lives, while taking on varying burdens of risk. Mapping the intermediate is both an empirical and methodological exercise. Empirically, it requires following the agents and traders, brokers and material objects that facilitate transactions and add, extract, or re-work different kinds of value. Methodologically, intermediaries and the intermediate are not only the objects of analysis but act as analytical tools in their own right, making the process and politics of transactions visible and tangible. Attending to the intermediate in our inquiries around money, currency and new digital financial technologies, thereby, offers new directions for grounding finance in politics and history and better connecting micro and macro and local and global economic processes.  相似文献   

16.
This article presents new research, which has the objective of quantifying the knowledge produced by historical technological innovations in the field of olive oil industrial heritage. It studies inventions related to the mechanical processes of the extraction of olive oil between 1826 and 1966, which are recorded in the Historical Archive of the Spanish Patent and Trademark Office. It uses a new adaptation of the methodology of knowledge management (KM) defined by Nonaka and Takeuchi. We have obtained the knowledge value of each innovation according to the level of technological knowledge registered at the time, while distinguishing between the historical evolution of inventions relating to milling and those relating to pressing. In the first analysis, the results show a recession in the quantitative level of knowledge in the olive oil sector with respect to the technological potential of the time. However, when contrasted with the events relating to industrial heritage at the time, it is possible to account for this technological evolution and prove the validity of the methodology used. The results show that general evolution of the knowledge generated has decreased, particularly in the pressing process, although this is not the case in the milling process.  相似文献   

17.
Expenses in the performing arts have historically increased at a rate faster than earned revenues due to the labour reliance of the sector. Flanagan (The perilous life of symphony orchestras: artistic triumphs and economic challenges. Yale University Press, New York, 2012) found that US symphony orchestras were able to avoid the negative consequences of this earning gap by fostering strong private support. In the present study, we find that, in contexts where private funding is not as readily accessible, like in Canada, arts organizations have more incentive to keep expenses under control. This can be understood in terms of resource dependence where government funding bodies, due to a homogeneous set of demands, put pressure on organizations to control their expenses and reach greater audiences. Using panel data covering a period of 8 years and forty-eight orchestras, the results show that Canadian orchestras, when compared to US ones, achieve a lower rate of expense increases over time and are more reactive to economic downturns.  相似文献   

18.
Correct interventions on cultural heritage should have as their starting point an accurate diagnosis of its health, in order to design a compatible care. NDTs seem to offer a promising way in this sense. This paper deals with the combined use of IRT and LDV for the investigation of historical thin vaults made by timber arches, reeds, and plaster and it demonstrates that they can effectively support a deeper knowledge of these vaults as it concerns the presence of detached areas among the different mortar layers of the plaster and of detached areas among the mat of reeds and the nailed connection with the wooden bearing elements. This is a very important goal because these ND methodologies can be employed only on the lower surface of these vaults and sufficiently far from it, and they do not have any mechanical interaction with the historical, eventually frescoed or stuccoed, plaster, thus saving money and time.  相似文献   

19.
The impact of video recorders on cinema attendance   总被引:2,自引:1,他引:1  
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20.
The impact of cultural economics on economic theory   总被引:1,自引:1,他引:0  
The paper asks what kind of impact cultural economics has had on the development of economic theory. Six research areas are discussed: productivity differentials between artistic and non-artistic labor, variations of the public good concept, particularly in relation to environmental goods, endogenous changes in preferences, long-term rates of return on paintings, impact of new media technologies and the autonomy of artistic valuation.It is shown that these topics have relevance beyond their applications in the cultural field, and that the theoretical issues involved challenge standard assumptions and standard modelling procedures in economic theory.Presidential address delivered at the 9th international conference of the Association for Cultural Economics, held in Boston, May 8–11, 1996.  相似文献   

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