应用电位活化理论研究青铜器的腐蚀与保护(二)——关于多孔氧电极的加速腐蚀机理研究

为了探讨铜盐等腐蚀产物对青铜器腐蚀的影响,采用腐蚀膏试验和微电极测试腐蚀电流的方法研究了氯化亚铜、碱式氯化铜、碱式碳酸铜等对青铜试片和铜电极腐蚀的影响,得出氯化亚铜是加速青铜器腐蚀的最有害物质的结论。红外光谱分析表明,以苯骈三氮唑为主钝化剂的高效防护剂同时改变了氯化亚铜的结构,起到了有效抑制青铜器腐蚀的作用。应用电位活化理论阐述了青铜器粉状锈小孔腐蚀的电化学行为,提出了氯化亚铜加速青铜器腐蚀的多孔氧电极催化模型。     

青铜病的闭塞孔穴腐蚀特征的研究

为探求符合文物保护要求的青铜器保护处理方法,对青铜病形成的过程和原因进行了模拟小孔腐蚀实验研究。对青铜模拟闭塞电池内的化学和电化学状态的变化,进行了不同Cl~-浓度和不同的pH值溶液条件下的电化学测试。实验结果证明,青铜闭塞孔穴腐蚀能导致蚀孔内Cl~-浓缩,pH值降低,腐蚀电流增大,局部腐蚀的加速,导致青铜病的形成。青铜病的闭塞孔穴腐蚀特征的研究,对进一步探求符合文物保护要求的青铜器保护处理方法具有较好的理论指导意义。     

澄城刘家洼遗址出土青铜器腐蚀成因研究

刘家洼遗址出土大量珍贵的青铜器对研究春秋早期芮国历史具有重要价值,但由于青铜器受到长期腐蚀影响,其蕴含的部分信息可能发生损失。为研究刘家洼青铜器的工艺、保存状况与稳定性,揭示关中东部黄土塬区出土青铜器的土壤腐蚀特征,并为文物保护修复提供参考依据,本工作对刘家洼青铜器腐蚀成因进行综合研究。本工作利用金相显微镜观察、扫描电镜-能谱、X射线衍射、拉曼光谱等分析手段对刘家洼遗址出土6件青铜器样品的锈蚀物相与锈层结构进行表征。结果表明,青铜器腐蚀产物以赤铜矿、孔雀石以及白铅矿为主。部分青铜器表面存在浅绿色粉状腐蚀产物,但并非含氯腐蚀产物。刘家洼青铜器锈层结构自金属基体向外依次为过渡层、原始表面内非金属层、原始界面、原始表面外原位沉积层及扩散沉积层。原始界面内非金属层Cu/Sn值低于基体,表明基体内的铜元素腐蚀后向外迁移以及锡元素腐蚀后形成锡石原位沉积。原始界面外Cu/Sn比值显著高于原始界面内非金属层,表明外迁的铜离子在埋藏环境作用下沉积。本工作通过对青铜器附着土壤样品pH值、氧化还原电位以及离子色谱分析,结果表明刘家洼青铜器埋藏环境为弱碱性氧化型环境,土壤中氯离子含量不高,这与出土青铜器的腐蚀...     

青铜病的闭塞孔穴腐蚀特征的研究

为探求符合物保护要求的青铜器保护处理方法,对青铜病形成的过程和原因进行了模拟小孔腐蚀实验研究,对青铜模拟闭塞电池的化学和电化学状态的变化,进行了不同Cl^-1浓度和不同的PH值溶液条件下的电化学测试。实验结果证明,青铜闭塞孔穴腐蚀能导致蚀孔内CI^-浓缩,PH值降低,腐蚀电流增大,局部腐蚀的加速,导致青铜病的形成。青铜病的闭塞孔穴腐蚀特征的研究,对进一步探求符合物保护要求的青铜器保护处理方法具有较好的理论指导意义。     

古代青铜器的腐蚀性破坏

青铜器为什么生了很多锈?为什么有的青铜器光滑无锈;有的青铜器却锈成了一堆,看不出器形?为什么青铜器表皮具有不同颜色的“地子”?铜器的锈又有不同的形状?为什么有的铜器非常坚固;有的铜器却又腐朽不堪,一碰就坏?所有这些问题,都可以用“青铜器的腐蚀”来解释和回答。因此,青铜器腐蚀对文物、考古工作者来说,是一个应该认识、应该了解的重要问题;特别是在博物馆收藏品中,对青铜器保管、保养、修复、复制等技术工作有着密切的关系,更应该了解它,认识它,并进而掌握它。这里,我仅将个人多年从事青铜器修复工作的一点经验、体会介绍出来,作为工作中的参考。     

青铜器腐蚀特征与土壤腐蚀性的关系

青铜器腐蚀特征与土壤腐蚀性的关系铁付德出土文物至少经历了土壤和大气两种以上的环境。古代青铜器经历了漫长的岁月,大都经历了两、三千年的历史,无论其流传经过怎样,始终与腐蚀环境相接触,只是这种腐蚀环境也处于不断变化之中。腐蚀是一种物质由于与环境作用而引起...     

九连墩墓地1、2号墓出土青铜器上锈蚀产物分析

采用XRD、XRF和显微照相等方法,测试分析了九连墩1、2墓中出土青铜器锈蚀产物的成分和物相组成,发现该产物的物相主要为氧化亚铜.结合埋藏环境土壤的理化分析,探讨了这些锈蚀产物的形成原因,以及其对青铜文物的影响.同时使用XRD分析方法研究了这批青铜器在大气中的腐蚀情况,发现了一部分文物已经滋生了"粉状锈".     

应用电位活化理论研究青铜器的腐蚀与保护

应用电位活化理论分析和阐述了青铜器腐蚀的观点和防护理念。对青铜器腐蚀的全过程提出了致密膜保护期、保护膜破坏局部腐蚀期和小孔腐蚀粉状锈加速期三个阶段的看法。用高效钝化保护剂对处于不同腐蚀阶段的青铜器保护膜进行修复和改性 ,结果表明 ,理论腐蚀电阻RC 从 10 5Ω提高到 10 7Ω ,并具有可间断涂覆、可回复的特点 ,可应用于青铜文物的保护试验。     

青铜器的腐蚀与保护探讨

青铜器在人类明史上占有重要的地位,它是祖先们大约在四千年以前,开始冶炼铜的过程中逐渐发现和掌握的精湛冶铜铸造技艺中独具特色的工艺,漫长的青铜时代为我们留下无数精美的古代青铜作品。在数千年遗留的传世品和出土青铜器中,有些由于外界环境的影响和自身结构的缺陷,出现了不同程度的腐蚀。要使这类受腐蚀的青铜器能够长期保存下去,关键是针对已腐蚀青铜器的情况,采取适宜的措施,抑制腐蚀的继续蔓延,尽量减少环境带给它们的危害。     

西宁博物馆汉代摇钱树的保护与修复

在数千年遗留的传世品和出土青铜器中,有些由于外界环境的影响和自身结构的缺陷,出现了不同程度的腐蚀,部分出土的青铜器甚至破烂不堪。要使这类受腐蚀的青铜器能够长期的保存下去,关键在于深入分析其损害因素,采取相应保护措施,尽快对受损器物进行保护修复。     

Telling small stories: spaces of knowledge and the practice of geography

This article examines how the practice of learning geography, and the arenas in which knowledge-making takes place, can be usefully positioned within changing histories of the discipline. It contends that networks of action – understood through the intersection of social sites, subjects and sources – present a conceptual framework and narrative focus for the re-consideration of specific episodes from geography's past. The interventions made here are informed and illustrated by a 'small story' about the doing of geography. Based on different personal accounts, the story revives a series of events, encounters, dialogues and images dating back to the winter of 1951 at Glenmore Lodge, Scotland. This educational institution in the Cairngorm mountains offered children from urban areas the opportunity to learn field studies and the skills of 'outdoor citizenship'. Initially, the focus falls on Margaret Jack, a 14-year-old field-course participant. Her learning experiences are traced through personal letters, a diary and a field journal dating from that time, and her recent recollections of this event. Margaret's account dovetails with the story of her field studies instructor, Robin Murray. Robin's role is traced through his learning experiences as a geography undergraduate at Aberdeen University, and the recent recollections of Catriona Murray, his wife.     

Das Wissen der Schulden. Recht,Kulturtechnik und Alltagserfahrung im liberalen Kapitalismus

The Knowledge of Debt: Law, Media Technique, and Everyday Experience in Liberal Capitalism. Performing an object such as ‘the economy’ hinges on practices of formatting knowledge. The article proposes to look at such instituting moments in connection with social conflicts over the legitimate rules of exchange. This is exemplified by way of recounting the story of the codification of Swiss bankruptcy law in 1889. In order to homogenize the legal procedures of debt collection and bankruptcy, two subject categories were instituted: ‘merchants’ and ‘non-merchants’. These different categories were thought to account for the diverging temporalities and spaces of credit exchange in everyday economic life. The introduction of the commercial register, a media-technical apparatus, enabled a formal distinction between ‘merchants’ and ‘non-merchants’. However, this boundary was contested and proved to be porose.     

Two radiocarbon dates for freshwater shells from hierakonpolis: Archaeological and geological interpretations

Shells of two species of freshwater bivalve (Unio willcocksi Bullen Newton and Etheria elliptica Lamarck) from the predynastic Gerzean (Nagada II) Decorated Tomb at Hierakonpolis, Egypt have given dates of 5000±90 bp for the tomb, and 12,900±120 bp for an episode of Nile terrace accumulation (correlated here with the Sahaba-Darau aggradation event). The archaeological and geological significance of these results is discussed, together with an outline of problems associated with radiocarbon dating of shell. Comparisons are made with the few other radiocarbon dates available for the Predynastic period in Egypt and possible reasons for the presence of shells in the tomb are considered.     

Some chronological implications of a fossil molluscan assemblage from a neolithic site at Brook,Kent, England

The later post-glacial history of a valley in the chalk escarpment near Brook, Kent, is described, based on molluscan stratigraphy, archaeological evidence and radio-carbon dating. Differences in size and colour banding, respectively, of fossil and living representatives of two species of land snails, Pomatias elegans (Müller) and Cepaea nemoralis (L.), are correlated with climatic change during the post-glacial period. The problems of the use of fossil shells of these species as samples for radiocarbon dating are discussed.     

China's Dynamic Industrial Sector: The Internet Industry

A Singapore-based economic geographer explores and analyzes the spatially uneven evolution of the Internet industry in China, arguing that the country's immense regional disparity in the provision of Internet services is best explained by the interplay of place- and path-dependence. The author demonstrates how the highly uneven regional endowments in relevant industrial and entrepreneurial resources have led to the substantial and persistent regional imbalance within China's emerging "new economy." His initial survey of the country's 100 leading Internet content providers (firms), identified from a listing of ca. 11,700 commercial websites, is selectively augmented to reflect an increase of over 70 million Internet users in 2007, reaching a total of 253 million in June 2008, and thus overtaking the United States as the world's largest Internet market. Journal of Economic Literature, Classification Numbers: L10, L86, O30. 6 figures, 1 table, 53 references.     

The 1911 International Exposition in Rome: architecture, archaeology, and national identity

This paper discusses the 1911 International Exposition in Rome and illustrates how this patriotic celebration of the fiftieth anniversary of the Italian Sate utilized symbolic landscapes of architecture and archaeology to promote nationalist sentiments of italianità and romanità centered on the young capital of Rome. Through modern art exhibitions at the Valle Giulia, scientific conferences at the Castel Sant’Angelo, archaeological exhibits on the Roman Empire in the Baths of Diocletian, and regional Italian pavilions in the Piazza d’Armi, exposition officials offered a complex representation of Italian national identity that was modern yet ancient, cosmopolitan yet bucolic, European yet regional, and imperial yet developing.     

The Rise and Fall of Alexander the Great – The Need for Medical Analysis: Reply to Commentaries

Alexander the Great died in 323 B.C. from an unknown cause. By elucidating the nature of his death, we can better interpret various aspects of Alexandrian history. Alexander’s death may have ensued from the sequelae of a congenital scoliotic syndrome. It would therefore be of significance to note that one of the greatest leaders in history who conquered much of the then known world may have been suffering from a physical disability.     

LEAD ISOTOPE ANALYSES OF ISLAMIC POTTERY GLAZES FROM FUSTAT,EGYPT*

Lead isotope analyses have been undertaken on a group of Islamic lead‐glazed pottery artefacts from Fustat, Egypt, spanning the period from the eighth to the 14th century ad , that had previously been the subject of a comprehensive typological, chronological, petrographic and technological study. Comparison of the lead isotope ratios for the glazes with those for lead ores from Egypt, Iran, Tunisia, Anatolia, Greece, Sardinia and Spain provided information on the possible sources of the lead used in the production of the glazes. The results show that the lead used in glaze production by the Islamic potters at Fustat was most probably obtained from distant ore sources in Iran or Tunisia, Sardinia, Spain and the Taurus Mountains. Different ore sources were favoured in different periods and, to a limited extent, for different types of pottery, but at no time did the Fustat potters use the potentially more accessible Egyptian ore sources.     

Australian Cenozoic Bryozoa, 2: Free-living Cheilostomata of the Eocene St. Vincent Basin,S.A., including Bonellina gen. nov

Schmidt, R., March 2007. Australian Cenozoic Bryozoa, 2: Free-living Cheilostomata of the Eocene St. Vincent Basin, S.A., including Bonellina gen. nov. Alcheringa 31, 67-84. ISSN 0311-5518.

Free-living bryozoans are diverse in the Eocene sediments of the St. Vincent Basin, South Australia. They include Bonellina pentagonalis gen. et sp. nov., Otionellina sp. cf. O. exigua (Tenison Woods), Otionellina sp. cf. O. cupola (Tenison Woods), Tubiporella magna (Tenison Woods), Celleporaria nummularia (Tenison Woods), and an indeterminate species only found as moulds. This diversity and abundance is highest in the sediments representing the initial transgressive marine facies, where they occur in ‘sand fauna’ bryozoan assemblages (e.g. with Melicerita and Siphonicytara). Free-living bryozoans decrease up-section and are absent from latest Eocene sediments, indicating a significant environmental shift.

Rolf Schmidt [rschmid@museum.vic.gov.au], Museum Victoria, Melbourne, Vic 3001, Australia; received 18.3.2005, revised 14.12.2005.