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81.
防霉防腐剂的抗流失性及防霉效果的研究   总被引:3,自引:0,他引:3  
为筛选适合木质文物使用的防霉防腐剂,对ML 208、咪鲜胺、戊唑醇、MV OP-10 4种防霉防腐剂进行了抗流失性和抑菌效果的研究。结果表明,4种药剂表现出不同的抗流失性,其抗流失性顺序为ML 208>咪鲜胺>戊唑醇>MV OP-10;MV OP-10的抗流失性虽较差,但雨水冲刷后仍具有较好的防霉效果;ML 208的抗流失性虽较强,但对霉菌的抗菌效果较差。  相似文献   
82.
Symbolic or incomplete trephinations are very common in Hungary in 9th–11thcentury AD skeletal series connected to early Hungarians, although they also occur in the preceding Avar Age (6th–9th c. AD) material. During the compilation of a database of regional cranial modification data, the authors found rare almond‐shaped symbolic trephinations in both periods, while these had formerly only been reported in Early Hungarian series. In this study, the new almond‐shaped lesions are described along with other symbolic trephinations of 14 newly found skulls from the 8th–11thcenturies AD in the Southern Great Plain of Hungary. The authors review the research of the phenomenon. The new findings may strengthen the theory of direct and very close cultural connections of these two ethnic groups, adding a new aspect to the debate over the origin and relationship of Late Avar (late 7th–early 9th c. AD) and Early Hungarian (9th–11th c. AD) populations. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
83.
The Baix Penedès Fault zone records successive karstic systems. The outcrops studied correspond to different segments of the fault, which were temporarily connected and disconnected, allowing for different diagenetic processes to occur. The first karstic system affected the Mesozoic rocks due to subaerial exposure after Paleogene compression, an event characterized by widespread dissolution and the generation of vug and cavern porosity. The δ18O values of the dolomitic sediment filling the initial vuggy porosity are similar to those of the host dolomite, indicating that the sediment comes from the erosion and reworking of the host rock. The second karstic system is related to the upward propagation of the Baix Penedès Fault. This deformation was characterized by random‐fracture fabrics with dolomite cement and sediment. The stable isotopes values and Sr/Ca ratios of both the dolomite cement and sediments are similar to those of the host rock. In contrast, the more depleted δ13C values indicate the influence of soil‐derived CO2 and the opening of the system to meteoric waters. During the third karstic event, the δ18O, δ13C, Sr/Ca ratios, and 87Sr/86Sr values of diagenetic cements suggest a marine signature, indicating that the karstic sediments were dolomitized under the influence of late Burdigalian‐Langhian marine waters. These marine waters were probably expelled from poorly buried sediments and circulated through faults producing dolomitization of the karstic sediments. A final karst system developed during a period of uplift and subaerial exposure. The δ18O values, the Mg/Ca and Sr/Ca ratios, and the high radiogenic values of the calcite cements formed during this period indicate precipitation from meteoric waters. The results of this study have implications for carbonate hydrocarbon reservoir analogs subject to karstic influence in the Valencia Trough and elsewhere.  相似文献   
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85.
This is the thirty‐fourth list of AMS radiocarbon determinations measured at the Oxford Radiocarbon Accelerator Unit (ORAU). Amongst the dates obtained for archaeological sites included here are the latest series of determinations from the key sites of Proskynas (Greece), Kova?evo (Bulgaria) and Khirbet Qeiyafa (Israel), as well as others dating to the Palaeolithic, Mesolithic and later periods. Submitters of the material provide comments on the significance of the results.  相似文献   
86.
The Canadian ‘staples thesis’ literature has documented both the risks (in the tradition of Harold Innis) and the opportunities (in the tradition of W. A. Macintosh) inherent in economies that are dependent on the export of minimally processed natural resources. The key risk is that of retarded long‐term growth as a result of a lack of diversification and over‐dependence on foreign capital and markets. This article argues that the demographic consequences of staples approaches to development also make it difficult to achieve diversification. It profiles Australia's Northern Territory as an example of a mining‐dependent (fiscal) economy that demonstrates a particular demographic profile consistent with what might be expected of a resource frontier. The article argues, however, that restrictive demographic characteristics persist (high sex ratios, high population mobility, disadvantaged position of indigenous people and remote dwellers) even though mining has become an insignificant direct employer (less than one percent of the workforce) and the services sector drives the labour market. This persistence can be linked to the Territory and federal government expectations of economic development patterns in the region and the frontier mythology created around the Northern Territory. Addressing the demographic imbalance is a critical step towards realizing ambitions for economic diversification.  相似文献   
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Although the “food desert” concept has captured the public imagination and spurred public policy efforts in many North American cities, the term has been critiqued by academics for being definitionally and methodologically vague, and for providing an incomplete picture of the complexity of food access. Rather than dismiss the study of urban, inner‐city food deserts, however, scholars can study disparities in retail food access through a historical, critical political economy lens to understand underserved retail landscapes as a product of capital formation and rescaling over time. The purpose of this article is to conduct such an analysis, using the case study of a low‐income community in Kingston, Ontario. Using historical research and qualitative interviews, the major finding of this analysis is that the physical accessibility of retail food appears to have declined over time in relation to the capitalization of the retail food sector. An imperfect relationship can be outlined over three phases of Canadian urban economic history to suggest that the food desert problem emerged largely in the transition from a decentralized, small‐scale, and neighbourhood‐embedded retail food industry to the scaled‐up, disembedded industry that now dominates the landscape. This industry‐level rescaling is contributing to a new urban politics of class and consumption through subtle, everyday activities such as food shopping.  相似文献   
89.
Avulsion fractures of the transverse processes of vertebrae have not been previously identified in the archaeological record. This paper provides a case study of a 21–25 year old male skeleton from the 10th century cemetery at Raunds Furnells (Northamptonshire, UK) with bilateral avulsion fractures of the transverse processes of the first thoracic vertebra. Possible aetiologies of this condition are discussed and conclusions drawn about the impact of this condition upon the individual. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
90.
Agricultural land‐cover changes in Eastern Ontario from 1826 to 2006: environmental effects. Stormont, Dundas and Glengarry (SDG) counties, Eastern Ontario, are among the first areas in Ontario to welcome settlers. In 1784, they established themselves in a forested land where wetlands are very important. Today, a large part of the wetlands has disappeared, but the landscape is wooded, masking the radical changes that took place over the course of the last two centuries. Analysis of census data from 1826 to 2006 allows the reconstruction of the history of land‐cover changes. It reveals the nature and rates of change for which a first analysis is presented. Four periods are identified. First, agriculture conquers the land and establishes its dominance. A plateau is reached in 1891 as agriculture maintains its supremacy until 1941. Then, as fast as agriculture invaded land, it fades away until 1986 when agricultural land‐cover stops shrinking. The opening of forest for cultivation was relatively slow in SDG because of biophysical and socio‐economical conditions associated with an absence of growth of agricultural population. Deforestation and wetland drainage led to a degradation of agricultural life but resulted in consideration of the environment in agriculture. Today, wooded and agricultural land covers are more balanced and environmental effects less acute.  相似文献   
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