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Gianna Giachi Chiara Capretti Nicola Macchioni Benedetto Pizzo Ines Dorina Donato 《Journal of Cultural Heritage》2010,11(1):91-101
The aim of the work is to set up a methodological approach to verify the effectiveness of the treatments of decayed waterlogged archaeological wood and to point out the proper thermo-hygrometric conditions for its preservation after treatment. The treatments were performed on wood samples of maritime pine (Pinus pinaster Aiton), oak (Quercus sp. caducifolia), elm (Ulmus cf. minor) and strawberry tree (Arbutus unedo L.), obtained from stems pertaining to the original vegetation found in the excavation site of the Ancient Ships in Pisa (Italy), and dated from seventh century BC to second century AD The utilised products were: Polyethylene Glycols (PEG) of various molecular weights, a Polypropylene Glycol (PPG 425), Trehalose (α-D-glucopyranosyl-α-D-glucopyranoside), and their mixtures, and also a Hydroxypropylcellulose (Klucel). The main objective to be pursued by the treatments was considered the stabilisation of the original size and shape of samples. The various steps of this approach were: the execution of a preliminary diagnostic survey on untreated samples; the characterisation of treatment solutions ‘as such’ to establish the property to be monitored during the treatment; the evaluation of the main physical characteristics of wood after the treatment were determined. Among the latter, the coefficient of dimensional stability during the exposure to a series of selected thermo-hygrometric conditions and the retention of consolidants after the treatment. These two measurements allowed the definition of the ‘efficacy of a treatment’, φT, a new parameter firstly utilised in this work. It measures the stabilisation capability of the percent unit of retained product, and its value permits to put in evidence the consolidants that stabilise wood with the lowest amount of product. Conversely, it was not possible to measure the Anti-Shrink Efficiency (ASE), one of the most utilised parameters for the evaluation of treatments, because of the serious distortions and fractures observed in all the heavily degraded untreated samples. 相似文献
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Gianna Katsiampoura 《Science & Education》2008,17(6):663-668
There is thus nothing paradoxical about the inclusion of alchemy in the ensemble of the physical sciences nor in the preoccupation
with it on the part of learned men engaged in scientific study. In the context of the Medieval model, where discourse on the
physical world was ambiguous, often unclear, and lacking the support of experimental verification, the transmutation of matter,
which was the subject of alchemy, even if not attended by a host of occult features, was a process that was thought to have
a probable basis in reality. What is interesting in this connection is the utilization of the scientific categories of the
day for discussion of transmutation of matter and the attempt to avoid, in most instances in the texts that survive, of methods
reminiscent of magic.
Gianna Katsiampoura is researcher of History and History of Science in the Byzantine Era and she has taught at the University of Crete, Greece. Her Ph.D. Dissertation is about Perception, Transmission and Function of Science in Middle Byzantine Era and the Quadrivium of 1008, Department of Sociology, Panteion University of Social and Political Science, Athens 2004. She has published papers in referred journals on History and Philosophy of Science in Byzantium. Her research interests include history and philosophy of science, history of education and the relation between history of science and political and economic history of Byzantium. 相似文献
| Gianna KatsiampouraEmail: |
Gianna Katsiampoura is researcher of History and History of Science in the Byzantine Era and she has taught at the University of Crete, Greece. Her Ph.D. Dissertation is about Perception, Transmission and Function of Science in Middle Byzantine Era and the Quadrivium of 1008, Department of Sociology, Panteion University of Social and Political Science, Athens 2004. She has published papers in referred journals on History and Philosophy of Science in Byzantium. Her research interests include history and philosophy of science, history of education and the relation between history of science and political and economic history of Byzantium. 相似文献
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G. Giachi S. Lazzeri M. Mariotti Lippi N. Macchioni S. Paci 《Journal of Cultural Heritage》2003,4(4):269-283
During the excavation of the Etruscan and Roman harbour of Pisa, several shipwrecks were found. The wooden timbers constituting the ship C and ship F (which date back to the first and the second century A.D., respectively, as attested by archaeological findings) were selected in order to collect information about the technological knowledge of the time. Pinus pinaster Aiton was essentially utilised for the planking of ship C and Quercus sp. caducifolia for that of ship F. The choice of timber for the other parts of ship C hull was much more differentiated. Ship C seems to be built in a careful way and its characteristics when added to its overall lightness, seem to reflect its use as a higher capacity boat built for sea sailing. Ship F seems more linked to short voyages in inner fresh waters. The utilisation of different woods was linked not only to the technological characteristics of wood, but also to their easy availability. Palynological analysis, carried out on the clay sediments embedding the shipwrecks, has shown that the flora of Pisa area in that time period would have allowed the acquisition of all the timber species used for both the ships’ construction, with the exception of the fig wood. However, a foreign origin of the timber from somewhere else in the Northern Mediterranean area has not been excluded. 相似文献
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Deborah L. Floyd Rivka A. Felsher Gianna Ramdin 《Community College Journal of Research & Practice》2016,40(1):5-22
In the 40th publication year of the Community College Journal of Research and Practice (CCJRP), the authors present a 39-year retrospective on research on the community college through the lens of the journal. It is not known exactly what the body of community college research wholly consists of. Without access to the larger picture of community college research, both the research and practitioner communities remain generally unaware of the existing research, areas lacking in study, and opportunities to build upon past research and to explore adaptation of practices that have been implemented at other institutions. The purpose of this study was to explore the evolution of community college research by surveying topics in community college research published over the past 39 years within the context of the CCJRP, highlighting implications for future research, policy, and practice. Findings from this content analysis study demonstrate more attention to student success, teaching and learning, and community college leadership than other topics. Overtime, topics such as college mission and international perspectives cycled across the decades, while others, such as access, held steady. Findings also show the popularity of policy and innovation topics and changes in authorship over time, particularly as related to gender. 相似文献
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