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41.
The melting of summer sea ice in the Canadian Arctic allows for better accessibility and therefore increased development of marine tourism. This paper highlights a significant increase in cruise ships and pleasure craft in the Canadian Arctic Archipelago since the 1990s, especially in the strategic areas of the Lancaster Sound and southeast of Baffin Island. Based on spatial analysis, cruise ships and pleasure craft were mostly sailing inside the primary corridors and outside the secondary corridors; this is particularly obvious for the fourth secondary corridor of the western Arctic. Moreover, marine tourism activity related to cruise ships or pleasure craft occurred within a distance of 15 nautical miles and beyond the outer limit of a corridor, whether primary or secondary. The Northern Marine Transportation Corridors Initiative is an important tool to manage marine traffic in the Canadian Arctic and we need to continue to encourage its development through a multipartite approach and taking traditional Inuit knowledge into account.  相似文献   
42.
Established techniques that have been successfully used to characterize pore systems in conventional reservoir rocks lack the resolution and scalability required to adequately characterize the nano‐ to micrometer scale pore systems found in shale and cannot be applied on stressed samples. We have therefore investigated the utility of Klinkenberg gas slippage measurements for shale pore structure characterization. In contrast to other approaches, slippage measurements characterize the effective porosity of core samples and can be applied at stress conditions experienced in the reservoir during production. Slippage measurements on horizontally and vertically oriented samples from the Eagle Ford Shale Formation, Texas, USA, at a range of stress states revealed two orders of magnitude in slippage variation over five orders of magnitude permeability range. Slippage measurements are negatively correlated with permeability and follow similar trends to those found in other studies on higher permeability rocks. The samples had varying degrees of slippage anisotropy, which allowed interpretation of the relative contribution of tortuosity and pore size to permeability anisotropy. Slippage and therefore average effective pore size was found to vary up to one order of magnitude at a given permeability, warranting investigation of the significance this might have on flow properties and ultimately hydrocarbon production from shale.  相似文献   
43.
The author advances an interesting and somewhat controversial argument for the dismal state of affairs in central Russia's countryside. Programs addressing problems in the countryside should focus not on reversing the tide of outmigration and agricultural employment loss, but on reducing labor intensity in agriculture and recognizing social and other realities working to the disadvantage of remote rural areas. What is needed is not expensive and unfeasible “revitalization” of the countryside, but the regulated decline of its agricultural workforce and the selective introduction of new labor-saving technologies and alternative land uses. Translated by H. L. Haslett, Leamington Spa, UK from: Evolyutsiya rasseleniya v SSSR, Chast' I (Evolution of Settlement in the USSR, Part I), G. M. Lappo, Zh. A. Zayonchkovskaya, and P. M. Polyan, eds. Moscow: Akademiya Nauk SSSR and Pol'skaya Akademiya Nauk, 1989, pp. 43-59.  相似文献   
44.
The Impact of Energy,Transport, and Trade on Air Pollution in China   总被引:1,自引:0,他引:1  
A team of U.S.- and China-based geographers examines the relationship between China's economic development and its environment by modeling the effects of energy, transport, and trade on local air pollution emissions (sulfur dioxide and soot particulates) using the Environmental Kuznets model. Specifically, the latter model is investigated using spatial econometrics that take into account potential regional spillover effects from high-polluting neighbors. The analysis finds an inverted-U relationship for sulfur dioxide but a U-shaped curve for soot particulates. This suggests that soot particulates such as black carbon may pose a more serious environmental problem in China than sulfur dioxide. Journal of Economic Literature, Classification Numbers: C50, F10, Q43, R40. 4 figures, 3 tables, 47 references.  相似文献   
45.
“华光礁一号”南宋沉船船板中硫铁化合物分析   总被引:1,自引:0,他引:1  
鉴于硫铁化合物对海洋出水木质文物的特殊危害,通过 X射线衍射(XRD)、等离子体发射光谱(ICP-AES)和 X射线光电子能谱(XPS)等分析手段,对“华光礁一号”南宋沉船船板残块中的硫铁化合物进行了分析研究。结果表明,所采集的样品中含有大量的 Fe和 S元素,并且其分布深度至少可达 4cm。两种元素的化学状态基本可分为铁的氧化物、硫铁化合物、硫酸盐和其它还原性硫四大类。其中,硫铁化合物主要以 FeS和 FeS2形式存在,并已部分氧化成硫酸盐。因此,在后续的保护处理过程需着重对其酸化过程进行控制,以有利于文物的长期保存。  相似文献   
46.
Carbon and nitrogen isotope analysis was undertaken on collagen extracted from eel bone from six Mesolithic and Neolithic sites in northern Europe. The results were compared with data obtained on other archaeological fish remains and modern eel caught in fresh and brackish water and from the sea. The possibility of discriminating between freshwater, brackish and marine signals in archaeological eel bone is evaluated and the implications for archaeology discussed. Our data suggest that eel found at coastal Mesolithic and Neolithic sites have carbon isotope signals consistent with a marine origin with no evidence of freshwater residency. The sample of eel bone from one inland site is small but indicates carbon isotope values more consistent with freshwater residency or at least values intermediate between freshwater and marine carbon pools.  相似文献   
47.
The differences between boiled or unboiled bones are not often studied. However, they are crucial to understand postmortem rituals and to establish defleshing procedures and mortuary practices. In this work, human bones boiled in sea or fresh water are characterized. The bone composition, as well as the compounds present in the resulting materials, shows that salt alters the boiling process mechanism. Hence, from structural and morphological criteria, it is possible to distinguish if a bone has been boiled in salt or fresh water. In both sets of samples, the smoothness of the bone surface depends on boiling time, but only in bones boiled in seawater, filaments are observed apparently pouring out of the pores.Those differences which are mainly morphological (smoothness of the surface) are explained in terms of a collagen diffusional mechanism favored by sodium and chloride ions. For a boiling time of 6 h, the surface is covered by a thick layer or crusts of degraded collagen. Experiments with seawater may be used as model experiments to simulate taphonomical alterations in bones exposed to salt water.  相似文献   
48.
The author got a chance to visit Turkey for investigating the damage of industrial facilities in the 1999 Kocaeli Earthquake which occurred on 17 August 1999 in the Kocaeli province of Turkey.

This report provides a brief investigation obtained through the seismic damage survey, particularly, focused on the damages to industrial facilities. The epicentral area in the Kocaeli province is the most industrial region of Turkey. Severe excitation attacked this region and industrial plants and structures were more or less damaged. Since the author could only visit a few sites, the report mainly describes the damages of two plants; TÜPRA? oil refinery where big fire occurred and TOYOTA-SA car manufacturing factory where no significant damage appeared.  相似文献   
49.
China's Economic and Political Penetration in Africa   总被引:1,自引:0,他引:1  
A senior American specialist on China and noted geographer presents a study of that country's economic and political penetration into the African continent. The author identifies three key elements of China's objectives and plan, namely (1) support for Chinese policies in international affairs, particularly with regard to Taiwan, (2) search for oil and other mineral resources, and (3) creation of a new market for Chinese goods and services in tandem with additional jobs in China. The paper includes four case studies highlighting economic activities stimulated by Chinese loans and investments in the Republic of South Africa, Egypt, Sudan, and Angola. Considerable attention is devoted to oil imports, exports of cheap consumer goods, and construction and repair of infrastructure by Chinese technicians and laborers, as well as the competition between Chinese imports and host-country manufacturing and the PRC's diplomatic support of rogue African nations. Journal of Economic Literature, Classification Numbers: F020, F210, F350, F540. 11 figures, 1 table, 47 references.  相似文献   
50.
Two economic geographers examine the impacts of economic transition on the efficiency of energy use in China, the second-largest energy consumer in the world. Following a brief review of reform and deregulation in China's energy sector, they proceed to systematically test the relationship between economic transition (conceptualized as a triple process of marketization, decentralization, and globalization) and energy intensity using a panel data set. The statistical units of analysis are China's 30 provincial-level administrative regions, facilitating the investigation of spatial variations in energy intensity. Journal of Economic Literature, Classification Numbers: O53, P20, Q40, Q43. 9 figures, 5 tables, 62 references.  相似文献   
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