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251.
一项新研究表明:氧气正在从越来越广泛的海域中逐渐消失,这可能又是一个由全球变暖所造成的环境问题。如果这个趋势继续下去,海洋生态系统将会遭到破坏。  相似文献   
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ABSTRACT

In this century Chinese tourists in Australia have rapidly become the most numerous national source. Relatively little is known about their socio-economic status, their geographical origins and expectations of tourism, and their attitudes to and perceptions of Australia, although every Australian state has devised a specific Chinese tourism strategy to tap into this market. Chinese tourism is concentrated in metropolitan areas in the eastern states, has evolved from group tours to individual plans, and is relatively high spending. Unless geographical and tourism research on Chinese tourism aligns with contemporary theoretical developments in tourism studies, the type of knowledge being produced will be limited. Whilst there is value in extending existing knowledge, important social insights into the Chinese tourists’ experience of Australia will not emerge. Although Chinese tourism is similar to earlier waves from East Asia, it constitutes a distinct component of the contemporary Australian market. A deeper understanding of this phenomenon requires the adoption of practice theories that privilege social practices as the entry point for theorising and conducting research. In advocating such an approach, we highlight challenges of linguistic and cultural differences, scale and governmentality in providing a qualitative research agenda for geographical and tourism studies’ engagements with Chinese tourism.  相似文献   
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Marked, 19th‐century kiln bricks and rocks from Caledonia Springs (CS) have black glass coatings that can easily be mistaken for glass produced at the elusive CS glassworks (c. 1844–1846). The glass‐on‐brick material, however, is more aluminous (nearly 20% Al2O3) than virtually any analyzed historical glass, and the glass‐on‐rock is compositionally similar to the rock itself, which shows clear signs of having undergone extensive melting. Mineral thermometry (Cpx‐Ol, Pl‐melt) indicates that parts of the kiln‐achieved temperatures of approximately 1200–1300°C. The CS samples show that caution must be exercised when identifying seemingly obvious waste glass near defunct glassworks sites. © 2005 Wiley Periodicals, Inc.  相似文献   
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This paper presents the results of a research programme conducted on the geotechnical centrifuge at The University of Western Australia to investigate coupled heat and contaminant transport in the soil surrounding a buried waste source. The phenomena which govern heat and contaminant transport through porous media are discussed, the principles of geotechnical centrifuge modelling are outlined, and relevant scaling laws that govern the relationship between a centrifuge model and the prototype, with respect to the problem of coupled waste transport, are presented. A model test, simulating two-dimensional migration from a buried heat and contaminant source, is described, and the results from four model tests are presented. The experimental data show that hydraulic instability is responsible for the transport of contaminant in the soil around the source and that the mode of instability is determined by the magnitude of the effective Rayleigh number.  相似文献   
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Information technology changes corporate office activity   总被引:1,自引:0,他引:1  
Corporate office activity is concentrated close to head offices in South Eastern England. It is often argued that information technology could change the location of offices by reducing the cost of provincial workplaces. The reorganisation of office functions associated with the introduction of information technology could also provide an opportunity to decentralise administrative structures.Two case studies in offices in manufacturing industry suggest that information technology can in fact be used to support either the centralisation or decentralisation of office work. The impact of the technology varies between corporate structures. In Unilever, a decentralised organisation, information technology has encouraged the decentralisation of routine administrative functions. In the more tightly-controlled Ford accounting function the mechanisation of accounts has been associated with the centralisation of administration at key sites. In both corporate structures it seems that information technology is being used to centralise important management functions.  相似文献   
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Reservoir resettlement in China: past experience and the Three Gorges Dam   总被引:2,自引:0,他引:2  
This paper reviews involuntary resettlement resulting from dam-building, which has been ignored relative to the dominant focus of migration research in China, rural to urban migration. Reservoir resettlement in China has a long history, often of misery and hardship for those displaced. Relocatees affected by the Three Gorges Project (1994–2009) on the Yangtze River face a similar situation. In China priority has been given to building the dam to provide electricity, flood control and navigation. Less attention has been paid to the problems of the people affected by the reservoir inundation. The rural population forced to relocate and rural-urban migrants in general have been discriminated against by national policies.  相似文献   
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