Dynamic Stability and Design of C-Bent Columns

Symmetrically reinforced bridge columns with a horizontal cantilever in one direction, called C-bent columns, tend to deform predominantly in the direction of applied moment when subject to strong earthquake shaking. For this reason, the strength in the direction of applied moment is generally increased in design. This article describes the use of inelastic dynamic time history analyses with a suite of ground motion records to quantify the amount of strength increase required to minimize likely peak and permanent displacement demands. It is shown that the strength should be increased by approximately 2.3 times the applied moment in design.     

ECONOMIC DEVELOPMENT AND ENVIRONMENTAL CHANGE IN THE WEST SIBERIAN PLAIN

The various types of natural landscapes of West Siberia are analyzed in terms of the environmental impacts of the more common forms of human activity. These are natural gas extraction and reindeer herding in the northern tundra; oil extraction and logging in the middle taiga, and agriculture as well as manufacturing in the southern wooded steppe and steppe. The impacts of human activity on specific natural processes (cryogenesis, bog formation, salinization) are discussed. The territory of West Siberia is broken down into three types of environmental impact regions: regions of significant impacts (from oil and gas extraction and agriculture); regions of moderate impacts (from logging and reindeer herding); and a region in which natural landscape structures have remained virtually unaffected by human activity.     

Comment on ‘Did China Import Metals from Africa in the Bronze Age?’

Lead isotope compositions provide a direct means of assessing provenance. The lead contents in bronzes cannot be used to argue against lead isotopes. Any claim for the origin of the source material for the origin of Yin‐Shang bronzes must satisfy the measured lead isotope compositions. Thus far, only southern African sources are found to meet this criteria.     

Clay‐shoveler's fracture: an uncommon diagnosis in palaeopathology

An archaeological case of clay‐shoveler's fracture was observed in an adult male exhumed from a Roman necropolis dated to the 1st–3rd century AD and located in the city of Barcelona, Spain. Clay‐shoveler's fracture is a breakage of a lower cervical or upper thoracic spinous process as a result of mechanical stress. Different mechanisms have been related to this injury, generally in labour‐related contexts. This paper reviews the literature concerning this uncommon finding, focusing especially on its mechanism and on activity‐related lesions. Copyright © 2006 John Wiley & Sons, Ltd.     

澳大利亚旅游网站信息流对旅游人流的导引:过程、强度和机理问题

这篇文章以澳大利亚旅游网站为对象,研究旅游网站信息流导引旅游人流的若干问题,旨在证实虚拟流动对现实流动的作用性。文章首先分析了旅游信息流因素的变化;而后透视了基于旅游网站功能性与服务性的信息流对旅游人流导引的过程;再后给出了旅游网站信息流对不同类型旅游人流导引的强度,最后从旅游网站使用比和旅游网站信息比两个方面揭示了旅游网站对旅游人流导引的机理。     

TECHNOLOGY AND PROVENANCE OF A COLLECTION OF ISLAMIC COPPER‐BASED OBJECTS AS FOUND BY CHEMICAL AND LEAD ISOTOPE ANALYSIS*

Chemical and lead isotope analyses were utilized to determine the composition, technology and origin of a collection of Islamic copper‐based objects found in Jordan. The atomic absorption spectrometry results show that the objects were made of different types of copper‐base alloys that contain various amounts of zinc, tin and lead. The use of brass, highly leaded brass and quaternary alloys of Cu‐Zn‐Sn‐Pb in the manufacture of everyday, household objects strongly points to Islamic traditions. The lead isotope compositions of the objects match very well that of the copper ore mined from the Dolomite‐Limestone‐Shale unit of the Arabah copper mines.     

安徽南陵出土部分青铜器研究

安徽省南陵县是长江下游地区最早而且规模最大的冶炼中心之一,其古代矿冶遗址可上溯至西周晚期。本研究对南陵出土的不同年代和类别的青铜器样品进行了金相检测及合金成分定量分析。结果表明,只有容器存在铜铅二元合金和铜锡铅三元合金,但是热锻淬火的容器却不含铅,含锡量恰好位于适合该工艺操作并具有良好性能的区间。兵器、工具、车马饰均为铜锡二元合金,说明当时的工匠对于合金成分配比与性能的关系有明确的认识。越式鼎腹部样品具有热锻淬火马氏体组织,同样的金属结构还见于汉代铜锣等乐器、峡江地区战国中晚期青铜剑、江都大桥镇南朝青铜器窖藏出土的多件青铜容器,而镇江地区出土吴国青铜戈则具有铸造淬火组织,工艺稍有差别。这些器物中发现高锡青铜淬火组织不是偶然的,高锡青铜热锻淬火技术至少可以上溯至春秋战国时期,用以改善高锡青铜的机械性能。     

The Use of Menthol as Temporary Consolidant in the Excavation of Qin Shihuang's Terracotta Army

Temporary consolidation is widely used to protect delicate artefacts or other fragile relics in art conservation. Although cyclododecane is extensively accepted, the safety‐related issues have become an increasing concern and its short working time is always annoying. Inspired by its low melting point, polar structure, well‐established safety profile, easy local availability and low cost, we propose menthol as a new temporary consolidant on the new excavation site of Qin Shihuang's Terracotta Army. In this paper, we offer a preliminarily exploration of the kinetics of menthol sublimation on two different matrices, its residue after volatilization, its penetrability and distribution in simulated terracotta samples, as well as other important properties in the laboratory. The results obtained from these tests reveal that the sublimation of menthol can be a zero‐ or a first‐order process, depending on the porosity of the matrices, and its best operational temperature resides in the range of 60–80°C. Finally, two field cases at the archaeological site of Qin Shihuang's Terracotta Army are presented to show that menthol is a very effective temporary consolidant.