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991.
Marine Protected Areas (MPAs) are a cost-efficient and management-effective tool. Fishery Resource Conservation Zones (FRCZs) are one type of MPA in Taiwan, and they were designated to ensure the sustainability of fishery resources since 1976; however, government appropriations are the only financing source for FRCZs, leading to manpower and equipment shortages for FRCZ management. This study selected the Touching and Suao FRCZs in Yilan County of Taiwan as cases studies. To assess the feasibility of establishing a sustainable financing mechanism for MPAs, the Contingent Valuation Method (CVM) was applied to examine respondents׳ willingness to pay (WTP) to setup a fund for FRCZ management. The empirical results indicated that approximately 90% of respondents would be willing to donate funding for MPAs, and the WTP per respondent is NT$586.51 (US$19.6). Thus, establishing an MPA fund is a feasible way to operate Taiwanese MPAs through a co-management framework involving the central government, local government, local communities and stakeholders. However, based on our empirical results, a co-management financing mechanism for MPAs should be established to ensure stable and diverse financing sources.  相似文献   
992.
Climate change impacts on marine environments have been somewhat neglected in climate change research, particularly with regard to their social dimensions and implications. This paper contributes to addressing this gap through presenting a UK focused mixed-method study of how publics frame, understand and respond to marine climate change-related issues. It draws on data from a large national survey of UK publics (N = 1,001), undertaken in January 2011 as part of a wider European survey, in conjunction with in-depth qualitative insights from a citizens’ panel with participants from the East Anglia region, UK. This reveals that discrete marine climate change impacts, as often framed in technical or institutional terms, were not the most immediate or significant issues for most respondents. Study participants tended to view these climate impacts ‘in context’, in situated ways, and as entangled with other issues relating to marine environments and their everyday lives. Whilst making connections with scientific knowledge on the subject, public understandings of marine climate impacts were mainly shaped by personal experience, the visibility and proximity of impacts, sense of personal risk and moral or equity-based arguments. In terms of responses, study participants prioritised climate change mitigation measures over adaptation, even in high-risk areas. We consider the implications of these insights for research and practices of public engagement on marine climate impacts specifically, and climate change more generally.  相似文献   
993.
为探讨耐热直接溶血毒素(Thermostabile direct hemolysin,TDH)在体内和体外对小鼠黑色素瘤细胞B16的抑制作用,本研究通过MTT法、克隆形成试验、凋亡试验、Caspase-8和Caspase-3的活性试验、线粒体膜电位的检测以及体内C57BL/6小鼠(Mus musculus)荷瘤实验,比较TDH作用于不同细胞的半抑制浓度(IC50),评价TDH对小鼠黑色素瘤细胞B16的体内外抑制作用。结果发现:人结肠上皮细胞NCM460、人正常肝细胞LO2、人肝癌细胞SMMC-7721和小鼠黑色素瘤细胞B16在TDH处理24 h之后,细胞的半抑制质量浓度IC50分别为151、118、54和48 μg/mL,正常细胞的IC50高出癌细胞近2~3倍。当质量浓度低于20 μg/mL时,TDH以剂量依赖性的方式抑制B16细胞的克隆形成,6 mg/kg TDH在移植瘤模型中显著抑制体内肿瘤的生长(P<0.001)。流式细胞术和荧光试剂盒检测表明:20 μg/mL的TDH能诱导19.4%的B16细胞发生早期凋亡,并激活Caspase-8和Caspase-3,但不影响线粒体膜电位。TDH具有体内外的抗肿瘤活性,可能通过细胞表面的死亡受体介导的凋亡信号通路引起凋亡,从而发挥抗肿瘤作用。  相似文献   
994.
Although there have been numerous studies of the meanings ascribed to terrestrial places, their applicability or otherwise to coastal and marine places has received limited attention. Through the process of photo-elicitation, the meanings ascribed to a remote coastal camping environment are examined, with the coastline of Ningaloo Marine Park in north-western Australia the focus for this study. Thirty participants were provided with digital cameras and the ascribed place meanings were explored when their photographs were discussed in subsequent in-depth interviews. Key meanings related to the physical environment providing opportunities for escape, participating in multiple marine-based activities, bonding with family and like-minded people, and offering a rewarding experience that makes everybody happy. This emergent meaning of ‘everybody's happy’ progresses the understanding of the affective elements of place, especially those realised by families and groups of friends. The paper traces important implications of this meaning, and provides a paradoxical perspective on isolation evident from the interviews, for managing coast-based recreation.  相似文献   
995.
Ecosystem services (ES) and ecosystem services assessment (ESA) have become common parlance in the environmental field. Scientists, policy-makers and activists have promoted the ES approach as a means of conveying the extent of threats to natural ecosystems with the goal of crafting socially acceptable and effective policy to address ecological threats and biodiversity conservation. Yet there are some significant challenges to wide acceptance of the ES approach which hinder its absorption into the mainstream geography literature. This paper reviews the historical development of the ES approach focusing on its relevance to applied geography at different stages of its development, describes the present state-of-the-art of ES, and synthesizes the results from several seminal papers and reports. I posit that there are two major stumbling blocks: 1) the difficulty of simplifying complexities between services so that statutory planning processes can incorporate the approach, and 2) the lack of cross-landscape assessment methods and examples. If we focus on the most immediately surmountable challenges to the ES approach much progress could be made in a short time. The subsequent and final substantive section of this review summaries these challenges and offers some suggestions for moving forward.  相似文献   
996.
The Philippine Sea Plate is located at the convergence zone of the Eurasian Plate,the Pacific Plate,and the Indo-Australian Plate.This paper divides the Philippine Sea Plate into two second-order tectonic units and eight third-order tectonic units by summarizing the marine geological,geophysical,and submarine geomorphological data of the Philippine Sea Plate collected for years and referring to the seafloor spreading theory and the trench-arc-basin system.The two second-order tectonic units are the West Philippine Sea block and the Izu-Bonin-Mariana arc-basin system.The former includes the West Philippine Basin,the Huatung Basin,the Daito Basin,and the Palau Basin,while the latter consists of the Kyushu-Palau Ridge,the Shikoku-Parece Vela Basin,the Izu-Bonin Arc,and the Mariana Arc.Furthermore,this study concludes that the Philippine Sea Plate has undergone three stages of tectonic evolution,namely the early stage of the evolution of marginal basins with Cretaceous basement(Early Cretaceous),the middle stage of the spreading of the West Philippine Basin(Eocene),and the late stage of the subduction of the Izu-Bonin-Mariana arc-basin system(Oligocene-present).The Kyushu-Palau Ridge is a window to discover the tectonic evolution of the Philippine Sea Plate due to its unique geographical location.  相似文献   
997.
Perfluorinated compounds (PFCs), widely used for their hydro-oil repellent properties, are almost non-degradable in the environment; there is scientific evidence that indicate bioaccumulation. They represent a threat to many organisms, because they are toxic and are endocrine disruptors. Scientific studies have demonstrated the presence of PFCs in blood and liver samples of fish, turtles, birds and mammals of marine ecosystems in different geographical areas. The aim of this study was to determine the distribution of PFOS and PFOA in blood samples of the marine turtle Caretta caretta, using a minimally invasive sampling procedure. 49 blood samples of marine turtle, taken from several Italian marine turtle rescue centers, were analyzed. While PFOA was never detected, measurable concentrations of PFOS were found in 15 blood samples; the values show a range from 1.14 ng/g to 28.51 ng/g (wet wt.). No differences between groups of samples taken from different areas were found.  相似文献   
998.
A baseline dataset from 2005 was used to identify the spatial distribution of macrofaunal assemblages across the eastern English Channel. The range of sediment composition found in association with each assemblage was used to define limits for acceptable change at ten licensed marine aggregate extraction areas. Sediment data acquired in 2010, 4 years after the onset of dredging, were used to assess whether conditions remained within the acceptable limits. Despite the observed changes in sediment composition, the composition of sediments in and around nine extraction areas remained within pre-defined acceptable limits. At the tenth site, some of the observed changes within the licence area were judged to have gone beyond the acceptable limits. Implications of the changes are discussed, and appropriate management measures identified. The approach taken in this study offers a simple, objective and cost-effective method for assessing the significance of change, and could simplify the existing monitoring regime.  相似文献   
999.
Geographic information service (GIService) has become popular in the last decade to develop applications for addressing global challenges. Performance is one of the most important criteria to help users select distributed online GIService for developing geospatial applications including natural hazards and emergency responses. However, performance accuracy is limited by the single-location-based evaluation mechanism while service performance is dynamic in space and time between end-users and services. We propose a spatiotemporal performance evaluation mechanism to improve the accuracy. Specially, a cloud and volunteer computing mechanism is proposed to collect performance information of globally distributed GIServices. A global spatiotemporal performance model is designed to integrate spatiotemporal dynamics for better performance evaluation for users from different regions at different times. This model is tested to support GIService selection in global spatial data infrastructures (SDIs). The experiment confirms that the proposed model provides more accurate evaluations for global users and better supports geospatial resource utilizations in SDIs than previous mechanisms. The methodology can be adopted to improve the services of other regional and global distributed operational systems.  相似文献   
1000.
Suspended particles (SP) are increasing dramatically in Bohai Bay, China and may affect the growth and composition of phytoplankton assembly. To determine the effects of SP on the growth of two dominant phytoplankton species, Phaeodactylum tricornutum Bohlin and Gymnodinium sp., we cultured and tested their growth characteristics under SP concentrations ranging from 0 g L−1 to 0.8 g L−1. Our results show that the increase in the SP concentrations results in significant decrease in the maximum cell densities and the maximum specific growth rates of these two species. The half maximal inhibitory concentration (IC50) of SP to P. tricornutum and Gymnodinium sp. were 1.07 g L−1 and 0.68 g L−1 respectively, indicating the inhibitory effect of SP on Gymnodinium sp. was greater than on P. tricornutum. These results suggest that SP inhibits the growth of the two algal species and P. tricornutum is more tolerant to SP than Gymnodinium sp.  相似文献   
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