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971.
The skeletal remains uncovered from the 2nd and 3rd century underground tombs of Palmyra, Syria, retain traces of arthritis and mottled enamel. A brown discoloration was also observed in the teeth. In order to clarify that these facts can be related to fluorosis, the teeth excavated from Tomb C and F in the Southeast Necropolis were analyzed. The fluoride contents of the fluorosis-suspected teeth (0.56 ± 0.16% (n = 7)) were higher than those of normal teeth (0.16 ± 0.18% (n = 7)). The highest content (0.85%) proved that 22% of the hydroxide in apatite was substituted by fluoride. The fluoride concentrations of the natural water including deep well water available today in this area ranged from 0.3 to 3.0 mg l−1. The highest fluoride concentration was found to be regulated by the dissolution equilibrium of fluorite, CaF2, through the process of evaporation and concentration in this arid region. Because of the common ion effect by calcium ions in a high concentration, the fluoride concentration was lower than that expected from the solubility product of fluorite (8.2 mg l−1). The mechanism of this process has probably remained unchanged since ancient times and therefore the drinking water used by the ancient people of Palmyra was estimated to contain fluoride at a level causing fluorosis. 相似文献
972.
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974.
Peter Ho 《Development and change》2006,37(1):3-28
This edited volume argues that China's development poses the greatest ever environmental challenge for the modern world in terms of speed, size and scarcity. The volume is organized around the greening of the Chinese state and society: can the inclusion of sustainable development principles into governance, management and daily practices by social actors lead to sustainable development per se? This introduction sketches the different scholarly camps around greening and sustainable development, ranging from sceptical to radical environmentalism. The contributions demonstrate that China is showing clear signs of greening as new institutions and regulations are created, environmental awareness increases and green technologies are implemented. However, the question remains whether this is sufficient to effectuate long‐term sustainable development. The key factors here are the sheer speed of China's economic growth, the size of its population, and the relative scarcity of its natural and mineral resources. Chinese development presents compelling reasons for rethinking the viability of greening. It is necessary to move beyond both alarmist visions of an environmental doomsday, and optimistic notions that incremental changes in technology, institutions and lifestyles are sufficient for sustainability. It might be more fruitful — and not only for China — to consider ‘precautionary’ rather than ‘absolute’ limits to growth. 相似文献
975.
The focus of this contribution is the Hong Kong Special Administrative Region (HKSAR) of China, and more particularly the processes of environmental reform in the region. The authors discuss developments in environmental policy over the past three decades and explore the utility of Ecological Modernization Theory as a basis for future environmental reform at the local level and as a mechanism for tackling broader regional environmental concerns. The contribution also explores linkages between technology policy and the environment in Hong Kong, arguing that while the SAR possesses certain competitive advantages, greater attention must be given to fostering and facilitating technological innovation in the environmental sector. 相似文献
976.
Although China is one of the world's largest producers and consumers of genetically modified (GM) crops and derived food products, little is known about the level of Chinese consumer awareness, understanding and acceptance of GM food. Initially, China pursued relatively aggressive policies for biotechnology development, but in recent years, the central government has become more sensitive to the potential environmental risks of transgenic food crops. To protect domestic biotech industries, the state plays a critical role in the politics of biotechnology, and does not allow GM food to become a prominent public issue. This contribution reports on a survey of 1,000 urban respondents. It demonstrates that most consumers lack the most basic understanding of biotechnology and its potential risks. The majority of the respondents (60 per cent) were either unwilling to consume GM food or were neutral about the idea, but when given neutrally‐worded information about potential GM food allergenicity, the willingness to buy dropped sharply. This might point to future scenarios of consumer resistance against GM food as has happened in European Union member states. This effect demonstrates the malleability of the Chinese consumer in a context of limited understanding and inadequate access to information. 相似文献
977.
The UNESCO Biosphere Reserve Program in Australia: constraints and opportunities for localized sustainable development 总被引:1,自引:0,他引:1
Since their creation under the auspices of the United Nations Educational, Scientific and Cultural Organization (UNESCO) Man and the Biosphere (MAB) Program in 1976, biosphere reserves have provided an international framework for linking protected areas with their associated working landscapes. In Australia, twelve biosphere reserves were added to the World Network between 1977 and 1982. That initial flurry of activity has been followed by twenty-five years of limited interest and development in biosphere reserves in this country, although evidence suggests that new energies are being directed to it. After sketching the origins of the biosphere reserve concept and its central tenets, we explore those environmental, cultural and institutional factors that may be promoting renewed interest in the program. We then review the initial implementation and current status of the Australian Biosphere Reserve Program. Factors supporting the limited success that exists in the program in Australia are highlighted, and the new form of biosphere reserve is illustrated with reference to Australia's recent and only urban biosphere reserve, at the Mornington Peninsula, in the state of Victoria. We speculate that prospects for biosphere reserves in Australia are brighter because of the provision for biosphere reserves under the Commonwealth of Australia's Environment Protection and Biodiversity Conservation Act (DEH 1999), the conceptual relevance of the biosphere reserve to bioregional and catchment management more generally and the continued success of existing model biosphere reserves. 相似文献
978.
Thigh‐spinning and spindle‐spinning, methods for making yarn and string, have been used through the millennia to produce substantial quantities of yarn for textiles. Productivity data were gathered in a replication study of thigh‐spun and spindle‐spun yarns and were recompiled from the literature. Calculated production rates allow comparison of the spinning methods. Factors influencing production rate include intrinsic fibre properties, fibre preparation and particular details of spinning technique, as well as the experience and motivation of the spinner. The role of efficiency in technology transition between thigh‐spinning and spindle‐spinning is discussed. 相似文献
979.
Wendy S. Shaw R.D.K. Herman G. Rebecca Dobbs 《Geografiska annaler. Series B, Human geography》2006,88(3):267-276
ABSTRACT. In an era of postcolonialism and postcolonization, Indigenous struggles continue. Within 'settler societies' issues of dispossession—particularly of lands—remain largely unresolved. As part of the discipline of geography's active movement away from its colonizing project, this introduction to this special edition of Geografiska Annaler B seeks to (re)focus a disciplinary lens, and (re)open a dialogue—and potential research trajectory - about 'indigenous geographies'. As the papers in this special issue demonstrate, new cultural geographies have begun a process of re-engagement with issues of indigeniety through careful, sensitive, inclusive, representative and emancipatory research projects. 相似文献
980.