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1.
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   

2.
Piperno, a Late Quaternary magmatic rock cropping out on the eastern side of the Campi Flegrei (Italy), is probably the most important building stone of Naples, used over a time-span from at least the Roman age until the beginning of the 20th century. Despite its wide diffusion in the monumental architecture of Naples, very little is known about this rock, as regards its technical features, as well as the geological aspects. This paper aims at providing a first overall contribution towards a rediscovery of this long-time-used material, in view of careful restoration works, which nowadays at Naples only take into account the proper geological features of the stone in a few peculiar cases. Thus, it seems of extreme importance to understand the basic parameters of Piperno and, above all, its response to weathering agents. Main mineralogical, petrographical and engineering–geological properties are presented here for the first time, with specific reference to two sampling areas, located at Pianura and Soccavo, in the western sector of the Neapolitan urban area. As far as many of its physico–mechanical features are concerned, Piperno extends over a wide range of values, which allow different varieties of the rock to be identified. This preliminary result is seemingly in accordance with data from old historical literature, which stated the existence of six horizons in the Piperno formation.  相似文献   

3.
This contribution is focused on collective and individual stories of precarity in Italy. At the present time, when work and the imaginaries socially constructed around it are more and more individualised and fragmented, imaginaries and collective references – whether they be social movements, trade unions or professional groups – have given way to ever more particularistic and singular experiences, which hinder the construction of a coherent identity for workers. In this scenario the question to be asked is then: how is it possible to elaborate a new collective imaginary of precarity and reclaim new rights? After a focus on the phenomenon of precarity in Italy, this contribution move to consider the activities of the network of San Precario, a cultural phenomenon that managed to develop new kinds of social claims based on bottom-up and horizontal practices. It is then discussed that the current return to an almost exclusively individual approach to the question of precarity, which forces subjects to bear the management of their professional life trajectories. Finally, an analysis of social movements' recent efforts of self-organisation and some reflections on the possible role of social sciences in elaborating tools for planning a renewed welfare system are offered.  相似文献   

4.
The survey of materials constituting the buildings of the ancient city centre of Naples and of their decay typologies was carried out. Reports were entered in a database which enabled us to draw two thematic maps in a digital format: one of materials and lithotypes, and one showing weathering. On this basis, quantitative evaluations of the lithotypes were carried out. The research pointed out that the use of different lithotypes was mainly as a result of their availability and/or ease of exploitation. Furthermore, the importance of the preservation of the quarrying sites was stressed, both for their historical and cultural interest and, above all, for possible forthcoming provisioning finalized to restorations. The analysis of the results, made on a geo-mineralogical basis, as well as the thematic maps, gives a basic tool which will be very useful to those professionals involved in preservation of cultural heritage.  相似文献   

5.
This paper presents the first investigation on the remote sensing of stone monuments by fluorescence lidar. The advantages of this technique are manifold and can lead to a fast, extensive and inexpensive control of the stone cultural heritage. The experiments were carried out in both the laboratory and the field, and include the survey of stones coming from different quarries, of epilithic photosynthetic biodeteriogens and of a monument, the Parma Baptistery. The results constitute a first step towards a non-destructive spectral analysis of stone monument surfaces.  相似文献   

6.
Consolidants based on tetraethoxysilane (TEOS) have been widely used for the consolidation of decaying stone heritages. These products polymerize within the porous structure of the decaying stone, significantly increasing the cohesion of the material. However, TEOS-based consolidants suffer from practical drawbacks, such as crack formation of the gel during the drying phase due to the developed capillary force, which is typical for TEOS-based consolidants. We have prepared new consolidants TEOS-based consolidants containing flexible (3-glycidoxypropyl) trimethoxysilane (GPTMS) and silica nanoparticles in order to reduce capillary force development during gel drying, and have characterized them for the application of stone consolidants. Different sizes of silica nanoparticles were used, which were smaller than the pore size of the tested stone. The properties of the TEOS/GPTMS/nanoparticle composite solution were compared with those of the commercial products Wacker OH and Unil sandsteinfestiger OH 1:1. The gelation time was similar to that of commercial consolidants, and the TEOS/GPTMS/nanoparticle solution was stable over a period of up to six months. The contact angle of the surface increased with the addition of the nanoparticle, as well as with the addition the GPTMS, which is higher than that of commercial Wacker OH. The addition of a nanoparticle, as well as GPTMS having flexible segment, provided a crack-free material, while the gels obtained from the commercial consolidants exhibited cracking.  相似文献   

7.
As universities are increasingly called by their national governments for a more entrepreneurial management of public research results, they started to develop internal structures and policies to take a proactive role in the commercialisation of university research. For the first time, this paper presents a detailed chronicle of how country-level reforms on Intellectual Property Rights (IPRs) were translated into organisation-level mechanisms to regulate university-patenting activity. The analysis is based on the complete list of patent policies issued between 1993 and 2009 by the population of Italian universities. Our evidence suggests that universities first dealt with legislative changes on IPRs by enacting isomorphic behaviours, then by creating a community of practices, and finally by leveraging on such community to influence government reforms on IP-related matters. We discuss our results in the light of institutional theory and public policy.  相似文献   

8.
Hybrid stone consolidants prepared from tetraethoxysilane (TEOS) and α,ω-hydroxyl-terminated polydimethylsiloxane (PDMS-OH) have been considered as one of the most promising approaches to improve the effectiveness of traditional alkoxysilane-based formulations. They have emerged as response to the negative reports commonly found in the literature: the resulting silica gel phase (SiO2) tends to develop fractures and fissures inside the stone as the gel shrinks during the drying stage. In this work, we employed SEM, solid-state 29Si NMR spectroscopy and compressive tests to characterize SiO2-PDMS hybrid gels. We report the morphological characteristics exhibited by gels prepared in vitro and in situ. It was found an appreciable reduction of gel fracture for hybrids prepared from 5% w/w of PDMS. As TEOS polycondenses, PDMS-OH is chemically incorporated into the gel matrix via Si-O-Si bonds. The inclusion of these elastic chains provides the necessary flexibility to resist the stress imposed by capillary pressure. Additionally, an important hydrophobic character is imparted to the stone.  相似文献   

9.
Adobe is a construction technique that uses raw clayey earth mixed and moulded to form blocks to realize a bearing wall. Romans were also used to add sand or coarse sand into the mixture to “degrease” clay and to allow to make it into a mixture. Fibres such as straw were often added into the mixture. Anyway, ancient home brick-makers have not had a chance to do scientific experimental investigation on the balance of ingredients and the optimisation of this production. This paper elaborates on how workability and mechanical properties of Roman ancient adobe earthen bricks change by varying the percentage of an on situ soil, straw and coarse sand into the mixture to produce them. The comparisons were also made with the only-earth samples. Breaking manners of all the samples were also compared.  相似文献   

10.
11.
The susceptibility to weathering of eleven carbonate and evaporitic Spanish building rocks was studied by means of dissolution experiments. Mineralogy, petrology, geochemistry and porosity of the rocks were also characterized in order to determine the potential relationships between these properties of the rocks and their dissolution rates. Rock slabs were submerged in a 0.1 M HCl acid solution for 72 h and the amounts of Ca, Mg and S released were measured, as well as the weight loss of the samples during the acid attack. Alabasters, which presented very low porosity, were dissolved to a lesser extent than limestones and dolostones in the time of the experiment. A significant positive correlation was found for connected with the weight loss of the rocks during dissolution and with the kinetic rate of Ca dissolution. Overall, the results highlight the influence of the porous network in the degradability of building stones by controlling their rate of dissolution. There is a positive correlation for all the rocks between weight loss along acidic attack and connected porosity, but no relationship between mineralogical and petrographical composition and susceptibility to dissolution.  相似文献   

12.
The performance of five synthetic coatings for the protection of stone monuments of Hellenistic and Byzantine period has been evaluated. The selected coatings included four commercially available siloxane-, siloxane/acrylic- and perfluoroether-based compositions, as well as a new composition based on newly synthesized fluoro-organosilane. The coatings were applied onto petrologically different stone substrates, such as marble, travertine, sandstone and a newly baked brick compatible with Roman period bricks, used for the restoration processes in Galerius Palace, Thessaloniki, Greece. The coatings' protective efficiency was investigated by measurement of water–stone contact angles, water vapor permeability, and water absorption by capillarity. The optical properties of the applied coatings were also investigated and they were also ranked with regard to their optical characteristics.  相似文献   

13.
In this paper the consolidating and protective products used in the restoration of stone manufactured objects of artistic interest are discussed; advantages of the different products and the relevant properties of the polymeric materials are underlined. The penetration of polymeric consolidating materials is very small and the in situ polymerisation of the monomers is suggested as an alternative technique to using macromolecular solutions. Some experimental results are presented showing that the in situ polymerisation improves the consolidating and the protective properties of polymers.  相似文献   

14.
栗子 《文化交流》2010,(8):31-35
在意大利第20届巴勒塔国际青少年音乐家钢琴比赛上,她在年纪最小的A组夺得第一名,并以一曲《浏阳河》获得全场唯一的“亚洲杰出音乐家奖”。这并不是偶然的昙花一现,此前她已经获得了5个浙江省金奖、第九届CCTV少儿艺术电视大赛钢琴儿童组金奖、2009年舒曼青少年国际钢琴大赛亚太地区儿童组第三名等大奖。  相似文献   

15.
An investigation has been undertaken at St Andrew’s church, Walpole St Andrew, Norfolk, to establish the underlying causes of the observed stone decay to the upper parts of the six stone piers. The stone decay was first recorded in the early 1930s. The salt-contaminated masonry within the church has been shown to undergo severe salt decay during the summer, with little damage occurring over the winter months. The south aisle piers have been shown to decay 2.5 times faster than the north aisle piers. Although crystallization–hydration cycles have been identified, the rate of decay is at its greatest when the cycling is relatively infrequent. This was not the expected trend. Furthermore, it has been shown that during extended periods where the ambient relative humidity is less than 75%, the rate of decay reaches a maximum. It is the length of this ‘drying’ period that apparently has the greatest influence on the rate of decay and could explain the significant difference in the rate of decay between the south and north aisle piers. The results have serious implications for passive conservation, where it is often recommended to lower the ambient relative humidity to well below the equilibrium relative humidity of the salt contaminant, to avoid crystallization–hydration cycles. Since, at the time of building, the church was situated on the coast, it is possible that the sodium chloride contamination occurred during the building process (1440–1520), particularly since the area was prone to sea-flooding at this time. Alternatively, the salt could have been applied as a treatment during the general restoration of 1897. Whatever the source of the salt, it seems likely that the ambient environment was changed by the insertion of a sealed floor in 1897, which could account for the onset of the salt decay.  相似文献   

16.
Rural buildings have undergone deep changes with the historical transition from traditional agriculture to industrial society. This paper discusses these trends in Italy, focusing on major changes in agriculture, design approach, and land-use planning, referring to some regional cases and relative building typologies. The analysis of the main historical treatises on the subject of farm building design allowed us to evaluate how the evolution of the technical approach influenced the architectural quality of rural buildings. This latter was traditionally based on a close relation between aesthetic values, functionality, and simplicity, broadly acknowledged only recently, as shown by the loss of landscape integration of farm buildings constructed in the last decades. By analysing the processes of reuse of historical buildings and construction of new farm buildings, we have found out different and time-evolving ways of referring to rural heritage and identity. In some cases, they have been considered important references, even through typological evolution aimed at combining traditional values with new needs and available techniques. In other cases, old farm buildings have been considered unsuitable things of the past, or rather have inspired new constructions based on an idealized and mystified concept of rurality. Since landscape integration of rural buildings plays a crucial role in the EU concept of agriculture, the choice of architectural quality postulates to be adopted for the design of new rural buildings is a key theme. Both consistency with pre-industrial tradition and typological discontinuity must necessarily consider consciously the relationships with historical buildings, whose important values have increasingly come to the fore over the last years. Once consistency with historical farm buildings is assumed as a design postulate, contemporary interpretation of traditional typologies through modern building techniques is a very challenging and topical field of study. Various degrees of consistency with traditional typologies are possible. Therefore, this approach calls for the development of analytic and metadesign methods aimed at decomposing rural building typologies into their essential physiognomical features, allowing designers to modulate them to meet ever-changing requirements.  相似文献   

17.
Titanium dioxide (TiO2) can be used to realize transparent self-cleaning coatings on stone surfaces as an active and preventive protection system, limiting cleaning and maintenance actions, reducing their costs in Architectural Heritage. This self-cleaning ability is due to photo-induced hydrophilicity on treated surfaces. The aim of this investigation is to analyze this effect, since it could bring to a greater water absorption, a potential source of damage for stone surfaces. Titania sol, obtained by sol-gel and hydrothermal processes, was deposited on travertine by spray coating, in two different ways. Water absorption by capillarity, static contact angle and a specific surface water absorption analysis were assessed before and after the TiO2 treatments. The effects of deposited amount of titania on the characteristics of treated surfaces were evaluated. It was shown that there were no evident changes in the substrate reactivity without ultraviolet (UV) light exposure, while it seems that hydrophilicity due to UV light does not lead to higher water absorption, thus encouraging the use of TiO2 coatings in the field of Architectural Heritage. However, before widely applying this conservative treatment, some further researches are recommended in order to better assess its durability and sustainability.  相似文献   

18.
The Sos Furrighesos necropolis (Anela) is considered to be one of the most important funerary monuments in Sardinia. The hypogeum consists of various graves, called Domus de Janas, which are decorated with Neolithic mural paintings and sculptures. This work was undertaken in order to clarify which techniques were used in the past, through the identification of pigments and binding media. The samples, scraped off from the paint surface, were studied by using various analytical techniques in order to characterise both the pigments and the binding media. The main problems concerning the characterisation were due to the small sizes (1–5 mg) of the samples and their complex nature. As regards pigments, X-ray diffraction and scanning electron microscopy-energy dispersive X-ray spectrometry analyses were performed on the samples. These techniques are well suited to the characterisation of inorganic pigments and have led to the identification of the red pigment as haematite. In order to characterise the organic binders, the samples were analysed by a procedure based on a gas chromatography–mass spectrometry technique, which allows proteinaceous and lipidic media determination in the same sample. In most of the samples, the presence of egg was suggested.  相似文献   

19.
Almost everywhere public intervention in cultural heritage (CH) conservation is widespread. Using Italy as a case study, the paper analyses public capital expenditure for CH conservation and investigates whether the high degree of specialization of contracting authorities affects the efficiency of CH conservation works. A two-stage analysis is carried out. At a first stage, a nonparametric approach (Data Envelopment Analysis—DEA) investigates the relative efficiency scored by each single work; at a second stage, the determinant factors of the scores variability are investigated. The empirical analysis shows that, ceteris paribus, the expertise affects the efficiency of CH works.  相似文献   

20.
景观地图与社区地图作为生态博物馆的实践工具,能够帮助人们阅读本地景观、展示地方价值、识别发展问题,同时增强社区凝聚力,促进乡村遗产价值传播。地图工具伴随生态博物馆实践在欧洲得到了广泛应用。对意大利实践中的地图工具进行理论研究与案例解读,总结经验要点,并结合国内实践相关问题,提出促进国内生态博物馆建设以及乡村遗产保护和乡村振兴的启示:地图工具能够有效增强居民对本地景观价值的意识;生态博物馆的实践不能忽略乡村社会经济发展议题;生态博物馆实践中应有更多文化景观视角研究的介入。  相似文献   

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