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1.
Rustum Roy 《Minerva》1984,22(3-4):316-328
Conclusion The questions of scientific choice which were left unresolved when the rapid expansion of academic science in the United States began in the early 1960s have come back to trouble the scientific community. There is now widespread dissatisfaction with the process of review by peers as one of the major systems for the allocation of public funds for research. While earlier criticisms had been brushed off by the assertion—unsupported by facts—that no other systems existed, the present situation cannot be so easily dismissed.A serious examination of other national and international arrangements shows that a wide variety of procedures are in use and there is no research which shows that one system is either more productive scientifically, or more cost-effective in bringing about valuable scientific research. New systems which may be considered should avoid the major defects of the system of peer review as now practised: the enormous waste of scientists' time, the great potential for conflicts of interest, and the inherent bias against innovation.The principal system which I have proposed here combines the best elements of peer review with the simplicity and efficiency of the use of a formula. Moreover, this formula based on peer review of performance incorporates all the elements for which the academic scientific establishment should be accountable to its patron, which is the public treasury. A final virtue of the proposed system is that it provides simple and convenient procedures through the use of numerical weighting factors for the policy-maker to guide the support of scientific research as a whole.  相似文献   

2.
This paper presents the results of a geochemical study on obsidian fragments by Inductively Coupled Plasma Mass Spectrometry associated with Laser Ablation (LA-ICP-MS). This analytical method, almost non-destructive, has proven to be a powerful tool for “in situ” determination of trace elements, and is very useful in characterizing and determining the provenance of obsidian fragments of archeological interest. Its major advantage is that 29 trace and rare earth elements can be analysed in a very short time, without any sample manipulation.Analyses were carried out on 27 representative obsidian samples, collected from the main geological outcrops of Sardinia and the minor islands of Lipari, Pantelleria and Palmarola, in the peri-Tyrrhenian area, and on eight obsidian fragments recovered from three different Italian archeological sites of Neolithic age. The geological samples show variable trace element and REE compositions, and differences in Cs, Y, Zr, Nb, Ba, La, Nd, Ho, Er and Yb were great enough to allow the various source areas to be distinguished. The fragments fall into seven compositional groups. Three, which are homogeneous but clearly distinct from each another, include the Lipari, Palmarola and Pantelleria samples. The other four groups refer to the obsidian of Monte Arci in Sardinia, already known in the literature as SA, SB1, SB2 and SC. LA-ICP-MS established the definite origin and source areas of the artefacts.Analytical results indicate that, for obsidian samples from the peri-Tyrrhenian area, significant geochemical differences exist in their trace and REE compositions, which identify their source areas and establish their provenance for archeometric purposes.  相似文献   

3.
This work is focused on the petro-archeometric characterization of the fine pottery production of the archaeological site of Gela (Sicily). Thirty-five samples coming from three Archaic and Hellenistic kilns and five coming from an Hellenistic house, were investigated by means of optical microscopy, XRD and XRF analysis. With the exception of some ceramics which are undoubtedly imported, all the samples have similar petrographic features, but on the basis of chemical composition, we can distinguish two different groups. The presence of two local productions is confirmed by the comparison with locally outcropping sediments and with archaic and modern bricks of sure Geloan production. This result is particularly significant for the definition of reference groups of this wealthy polis that played an important trading role in the Mediterranean area.  相似文献   

4.
From 18 archaeological sites of the Lagoon of Venice 75 bricks belonging to Roman and medieval building levels have been analysed. Chemical composition and geometric measures allow the characterization of a group of 24 Roman bricks of Imperial age. The group formed by means of fuzzy c-means cluster analysis applied on chemical data have been tested by principal component analysis and finally subjected to discriminant analysis to estimate the relative weights of original variables and classify new elements. Correlations among the data of the major chemical elements confirm the reliability of the complex of chemical data. The aim of this research was to obtain a chemical characterization of Roman bricks (and later, of the medieval ones) coming from the lagoon of Venice thus making it possible: 1) to recognize the age of a brick by means of its chemical analysis; 2) to date the layers of archaeological excavations or the ground where there are medieval building foundations by means of membership bricks; 3) to calculate the rate of local ground lowering in the elapsed years by the difference in level from one layer to another; 4) to estimate local rates of land subsidence by comparison with mean values already known.  相似文献   

5.
宽敞的屋子里摆满了各种各样精巧可爱的竹编:玲珑剔透的竹篮、上圆下方的箩筐、圆圆的竹筛、尖尖的斗笠…… 墙上挂满了琳琅满目的竹编书画,线条如行云流水、灵动飘逸…… 江安然的竹编是临安昱岭关下一道美丽的风景。  相似文献   

6.
Several authors or practitioners have remarked that Q-switched lasers have an immediate blackening effect on mineral pigments such as vermilion (HgS), minium (Pb3O4), white lead [2PbCO3. Pb(OH)2], malachite [Cu2CO3.(OH)2] and yellow ochre (FeOH2). A similar blackening effect can also be obtained on veined Carrara marble. This stone contains several trace elements, particularly iron and manganese. The latter is responsible for a particular response in electronic paramagnetic resonance spectroscopy (EPRS). We investigated the effect of a Q-switched Nd:YAG laser irradiation on the EPRS trace of Carrara marble. Further experiments were performed with the same analytical tool on synthetic calcite powders that had been doped with iron or manganese. It appeared that no significant change of EPRS trace could be put into evidence after laser irradiation of both bulk Carrara marble or doped calcite powders, although some samples had actually blackened. It is concluded that the blackening effect is not due to an oxidation of manganese ions. Colour measurements were also performed within the framework of this investigation. They showed that the colour shift to black is proportional to the fluence applied to the stone surface  相似文献   

7.
Salt crystallization is a major cause of damage in porous materials such as stone, brick and ceramics. The paper reports results of an analytical study on tiles of glazed ceramics that are seriously damaged by acetate salt crystallization. Measurements of the ionic composition of the salt mixture in the tiles and in the efflorescences were carried out. Based on the available information on the phase equilibria in the system comprising of the main constituents chloride, nitrate, acetate, calcium and sodium, the crystallization pathways of the various solid phases are traced. It is shown that a combination of qualitative XRD analysis of the phases present in the efflorescences together with a quantitative determination of the ionic composition is sufficient for the quantitative analysis of major crystalline species in the efflorescences, i.e. Ca3(CH3COO)3Cl(NO3)2 · 7H2O, thecotrichite, and NaCl, halite. The concentrations of these salts are obtained from a solution of the mass balance by least squares analysis. Their formation from the salt mixtures present in the tiles that are subject to acetic acid vapor attack is consistent with the solubility diagram of the above mentioned quinary system. Finally, the possibilities of preventive conservation of salt contaminated ceramics in typical museum environments are discussed.  相似文献   

8.
Substitution of slate roofing tiles is a conventional operation during building restoration, since tiles are very difficult to restore or clean because of the high degree of alteration they suffer. Criteria for replacement of historical building stones must be based on geological, geotechnical and esthetic parameters, among which color is of great importance. In this sense, this paper constitutes a comprehensive and useful colorimetric study of roofing slates from the Iberian Peninsula, for the purposes of restoration. The color of 50 commercial varieties of roofing slate mined in quarries from the 12 mining districts in the Iberian Peninsula was analyzed with a spectrophotometer device, by considering the CIELAB color space. The results of the study were used to develop a protocol for characterizing the color of roofing slate and to define the color range of roofing slate from the Iberian Peninsula. In addition, the similarities and differences in the color and microstructure of the different commercial varieties of Iberian roofing slate were established and the limit of acceptability of replacement of one type of slate by another was determined. Parameter hab was found to be the most important CIELAB color coordinate as regards the formation of homogeneous color groups, and the specular component excluded (SCE) mode was most sensitive as regards detecting color differences between two samples.  相似文献   

9.
Fifteenth century porcelains and celadons are the most interesting ancient Vietnamese ceramics, both from the material and aesthetic points of view. This paper reports on composition, microstructure and technological processing of the Chu Ðâu-My Xa (Hai Duong province) ceramics. Samples come either from the kiln site or from the Cù Lao Chàm (Hôi An) shipwreck. Chemical analysis, scanning electron microscopy, EDX analysis, X-ray diffraction, Raman spectroscopy, thermal expansion/shrinkage and open porosity measurements were systematically performed. The results show the Ca (+K)-based glaze, high-temperature-fired bodies, by one- or multi-step firings. Mullite phase (3Al2O3·2SiO2) was formed in large amount indicating the true porcelain quality of the samples under study. The matrices used for overglaze colouring (e.g., the green, red and metallic-lustre) are lead-based low-firing-temperature glasses. Comparison was made for the structural elements and fluxing agents between the 15th century Vietnamese porcelains and the time-corresponding Chinese ones.  相似文献   

10.
The application of a new class of organogels as cleaning tools for painted surfaces is described. It combines some of the most attractive features of cleaning liquids and normal gels while diminishing the deleterious characteristics of both. Thus, the ‘latent’ gellant, polyethyleneimine (PEI), reacts with CO2 at room temperature in solutions of several organic liquids to produce an ammonium carbamate form (PEICO2). This charged species organizes itself into 3D polymer networks which immobilize the liquids as gels. The properties of the original solution (i.e. a free-flowing liquid) are re-established immediately after addition of a small amount of a weak acid which displaces the CO2 molecules and makes the PEI chains positively charged. The visual changes are substantiated by rheological analyses. Results from analytical tests to determine the utility of these gels as cleaning tools for painted surfaces of historical and artistic interest, have been obtained from contact angle and FTIR measurements as well as visual comparisons of the surfaces before and after application of the gels. The analyses indicate that the PEICO2-based organogels were very effective in removing different surface patinas from painted supports. A surface layer of dammar was completely removed from a test canvas with oil paint, an aged painting from the XIX century, and a XV century oil-on-wood panel attributed to Mariotto di Cristoforo. Finally, a surface acrylic polymeric resin (used in a restoration performed during the 1960s) was also successfully removed from Renaissance wall paintings decorating the Santa Maria della Scala Sacristy in Siena, Italy. The isothermally rheoreversible gel approach described in this work represents a new, highly versatile, and very efficient method for removing aged surface patinas from works of art.  相似文献   

11.
Orchids have fascinated humans since ancient times. Not only the particular morphology of their flowers and hypogean organs, but also their reproductive biology have inspired myths, legends and popular traditions in many cultures, all around the world. Despite these facts, their representations on ancient artefacts have never been described in the scientific literature. No clear data exist for Eastern culture, and in Western countries, the first certain representations of orchids in art date back to the XV-XVI century CE. This paper documents different identifications of orchids on Roman monuments changing the common belief that these plants first appeared in art more recently. Floral elements of Cephalanthera spp., Spiranthes spiralis (L.) Chevall, of Orchis tridentata Scop., and of other orchids were observed in different architectonical elements (cornices and ceilings) throughout the Roman period, and in the external frieze of the Ara Pacis monument (I century CE). These representations seem to refer to a symbolism of fertility and sexuality, and their absence in medieval time can be explained only considering religion influences.  相似文献   

12.
Irwin Feller 《Minerva》2009,47(3):323-344
Neoliberal precepts of the governance of academic science-deregulation; reification of markets; emphasis on competitive allocation processes have been conflated with those of performance management—if you cannot measure it, you cannot manage it—into a single analytical and consequent single programmatic worldview. As applied to the United States’ system of research universities, this conflation leads to two major divergences from relationships hypothesized in the governance of science literature. (1) The governance and financial structures supporting academic science in the United States’ system of higher education are sufficiently different from those found in many other OECD countries where these policies have been adopted to produce political pressures for an increase rather than a decrease in governmental control over university affairs. (2) The major impact upon academic science of performance measurement systems has come not externally from new government requirements but internally from the independent adoption of these techniques by universities, initially in the name of rational management and increasingly as devices to foster reputational enhancement. The overall thrust of the two trends in the U.S. has been less a shift as experienced elsewhere from bureaucratic to market modes of governance than the displacement of professional-collegial control by internal bureaucratic control.  相似文献   

13.
Different techniques and tools currently exist to generate three-dimensional models of small elements, buildings and cities. Apart from being easier to interpret than two-dimensional drawings, these models facilitate data necessary for reconstruction projects, preservation or rehabilitation of the architectural or archaeological heritage. Traditional surveying only enables us to obtain discrete information of the characteristic lines that define each surface, edge, slope change etc. whereas work with massive capture techniques allows us to obtain continuous points of the surfaces. Photogrammetry or laser scanning combined with conventional photography provides information of the building in addition to its geometry. We carried out a review of the different techniques showing the advantages and disadvantages of each technique as well as the information that can be obtained by applying these techniques to the survey of the great Gate of Antioch in the town of Aleppo, declared a World Heritage Site by UNESCO in 1986, in Syria.  相似文献   

14.
Here we present the framework of a new approach to assessing the capacity of research programs to achieve social goals. Research evaluation has made great strides in addressing questions of scientific and economic impacts. It has largely avoided, however, a more important challenge: assessing (prospectively or retrospectively) the impacts of a given research endeavor on the non-scientific, non-economic goals—what we here term “public values”—that often are the core public rationale for the endeavor. Research programs are typically justified in terms of their capacity to achieve public values, and that articulation of public values is pervasive in science policy-making. We outline the elements of a case-based approach to “public value mapping” of science policy, with a particular focus on developing useful criteria and methods for assessing “public value failure,” with an intent to provide an alternative to “market failure” thinking that has been so powerful in science policy-making. So long as research evaluation avoids the problem of public values, science policy decision makers will have little help from social science in making choices among competing paths to desired social outcomes.  相似文献   

15.
Superstar museums are characterized by (1) great prominence among tourists and world fame among the general population; (2) a large number of visitors; (3) a collection of generally known painters and individual paintings; (4) an exceptional architecture; and (5) a large role of commercialization, including a substantial impact on the local economy. The superstar phenomenon is caused by factors both on the demand and the supply side of the market. Superstar museums are forced to offer total experience to the visitors; they have to relate to events in history, technology, politics, films and TV, and they have to provide for everything from education, food, gifts, shopping to entertainment. The development of superstar status strongly affects museum policy. The strategic orientation emphasizes visitors' demands; the organization has to be decentralized into processes each devoted to particular segments of visitors, to special exhibitions or support activities. There are also major consequences for human resource management, in particular, relating to flexibility and staff composition of paid employees and volunteers.  相似文献   

16.
The paper focuses on an interdisciplinary research project concerning the preservation of the XVII century monumental building of Monte di Pietà in Naples, Italy. The building underwent a series of restorations being the structural walls affected by humidity and cracks. The importance of this monumental building in the historical city center of Naples led to design an extensive surveying program to provide the designers of strengthening with a detailed investigation of the geometry of the entire structure, and particularly of the entrance façade, with great details on several materials, thicknesses and restraints. A preliminary investigation was performed on the historical phases of this monumental building to have a clear knowledge of its vicissitudes, and then in situ structural assessment included 3D laser scanner techniques probing radar, in situ stress measures. This surveying phase was crucial especially for the subsequent Finite Elements modeling (F.E.M.) of the façade. The scope of the numerical refined analyses was to evaluate the state of stress in the structural elements of the façade putting in evidence structural ‘weak points’ and finally to design a retrofit intervention having a detailed map of the ‘intervention areas’. The theoretical damage assessment has been compared with on-site assessment and in situ stress measures. The damage primarily concerned the entrance façade and its valuable decorations. Furthermore, the basic principles for the design of the strengthening have been discussed.  相似文献   

17.
Historical evidence on the use of mortars to meet several needs has existed for millennia. With reference to the characteristic historical periods of the city of Rhodes, mortar sampling was performed on historical constructions, masonry and architectural surfaces. In the present work the different mortar technologies are investigated aiming to answer questions regarding their finality, i.e. whether their differences arise mainly from the various historical periods of construction or from the purposes they had to serve, imparting to the mortars the properties required by their function in the structure. Mineralogical, chemical, physical and mechanical investigations have been performed on characteristic samples after gradation. The exponentially declining function of the ratio CO2/H2O structurally bound to the CO2 content shows a continuous evolution of the kinetics governing the various mechanisms of carbonation of the binder or the formation of hydraulic components during setting, hardening and ageing of the mortars. The grouping of mortars in well-distinct ‘hydraulic levels’ is ascribed to the physico-chemical cohesion and adhesion bonds developed at the matrix and matrix/aggregate interfaces, respectively, allowing for the mortars to either bear continuous stresses and strains as joint mortars or provide compact impermeable renderings which harden even more on contact with water. Hence, parameters determining the diversification of the resulting mortar/matrix types concern the raw materials employed as binding materials and the production processing.  相似文献   

18.
The concentrations of CO2, CO, formaldehyde (H2CO) and water vapour were simultaneously monitored in various sections of a mountain church situated in the village of Rocca Pietore in the Italian Alps. The performance of a conventional, hot-air heating system and a novel design for heating the church, consisting of low-temperature heating elements, such as electrically heated pews and carpets, were compared for the supply, transport and removal of gases, the deposition and/or transformation of which may affect the preservation of displayed works of art. Experiments with sulphur hexafluoride (SF6) tracer-gas showed a considerable influx of external air through the hot air carrier ducts of the old heating system, and also the leakage of the internal air mostly via the apertures of the doors. The ventilation rates for the total volume of the church with the hot-air heating system (on for 1.5 h), the new heating system (on for 2 h), and without heating were calculated to be 0.25, 0.18, and 0.13 h−1, respectively. Without heating, a nearly homogeneous distribution of gases has been observed along both the horizontal and the vertical cross-sections of the church. Immediately after switching on the hot-air heating system, the levels of CO2 and water vapour showed a sharp increase. After turning this system off, the levels of gases showed a slow fall and they developed a highly non-homogeneous spatial distribution indoors for many hours. In the upper region of the church, being airtight, higher concentrations of the pollutants could be detected. The low levels of CO and H2CO, mostly originating from incense burning during services, were correlated to that of CO2. The hot-air heating system has been proved to present a potential deterioration risk to artworks, as it increases the supply, transport and deposition probability of air pollutants. On the other hand, the novel, symmetrical heating system eliminates these undesirable effects, thus its application is advantageous to all churches involved in the preservation of works of art.  相似文献   

19.
20世纪以来,包括易学文献在内的一系列重大考古发现极大地开阔了人们的学术视野,对《易经》在西方的译介产生了深刻的影响。西方学者在翻译和诠释的过程中用出土易学文献来替代通行本部分对应文字,或者结合甲骨文、金文以及古文化遗址的考古发现对《易经》的意义进行重塑,打破传统经学的藩篱,在《易经》的诠释上走出一条全新的道路。  相似文献   

20.
Salt crystallization in porous materials constitutes one of the most frequent causes of decay of buildings in a wide range of environments. Up to now no definitive solution exists to limit salt crystallization damage, unless of removing either the salt or the moisture. The possibility of making the process of salt crystallization less harmful by means of crystallization inhibitors has only recently been considered. Crystallization inhibitors are known to delay nucleation and to modify the growth rate of the crystals in bulk solution, but their possible application for the prevention of salt decay in porous material is still controversial.The present paper reports a series of systematic investigations performed on three different materials (a limestone, a sandstone and a brick) contaminated with two types of salt (sodium chloride and sodium sulphate) and two types of inhibitors (sodium-ferrocyanide and diethylenetriaminepentakis methylphosphonic acid). Drying experiments have been performed to study the effect of the inhibitors on the salt solution transport. Accelerated crystallization experiments have investigated the possible consequences of the application of the inhibitor on salt crystallization damage (quantified as material loss).Environmental Scanning Electron Microscope (ESEM) has been used to study how the presence of inhibitors affects the crystallization morphology of salt in the material.The results show that the effect of the inhibitor strongly depends on the type of substrate. NaFeC, when applied on NaCl contaminated limestone and brick was able to enhance the drying and to favour the appearance of efflorescences, whereas the effect on the sandstone was very limited. DTPMP enhanced the drying of Na2SO4 laden sandstone, but had no influence on the drying of both brick and limestone. These different have been attributed to the properties of the materials, in particular pore size distribution and composition.The effects of the inhibitor on salt crystallization damage were less evident: no differences in surface damage, quantified as material loss, were observed between specimens with and without inhibitor.  相似文献   

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