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31.
High-resolution temporal rainfall data sequences serve as inputs for a range of applications in planning, design and management of small (especially urban) water resources systems, including continuous flow simulation and evaluation of alternate policies for environmental impact assessment. However, such data are often not available, since their measurements are costly and time-consuming. One alternative to obtain high-resolution data is to try to derive them from available low-resolution information through a disaggregation procedure. This study evaluates a random cascade approach for generation of high-resolution rainfall data at a point location. The approach is based on the concept of scaling in rainfall, or, relating the properties associated with the rainfall process at one temporal scale to a finer-resolution scale. The procedure involves two steps: (1) identification of the presence of scaling behavior in the rainfall process; and (2) generation of synthetic data possessing same/similar scaling properties of the observed rainfall data. The scaling identification is made using a statistical moment scaling function, and the log–Poisson distribution is assumed to generate the synthetic rainfall data. The effectiveness of the approach is tested on the rainfall data observed at the Sydney Observatory Hill, Sydney, Australia. Rainfall data corresponding to four different successively doubled resolutions (daily, 12, 6, and 3 h) are studied, and disaggregation of data is attempted only between these successively doubled resolutions. The results indicate the presence of multi-scaling behavior in the rainfall data. The synthetic data generated using the log–Poisson distribution are found to exhibit scaling behaviors that match very well with that for the observed data. However, the results also indicate that fitting the scaling function alone does not necessarily mean reproducing the broader attributes that characterize the data. This observation clearly points out the extreme caution needed in the application of the existing methods for identification of scaling in rainfall, especially since such methods are also prevalent in studies of the emerging satellite observations and thus in the broader spectrum of hydrologic modeling.  相似文献   
32.
Twenty-five drinking water samples collected from the household property and from the Sydney Regional Municipality well bores and lakes were analyzed to evaluate the various inorganic parameters, level of concentrations of the priority elements and polyaromatic hydrocarbons (PAHs). The pH of the majority of the water samples was below the guidelines adopted by Health and Welfare Canada (1996), although the drinking waters supplied by the Sydney Regional Municipality were within the guidelines. Only three water samples (13 and 14: Point Aconi area and 16: Port Morien fish plant) have elevated concentrations of various PAHs compared to the detection limit. Eight samples have higher concentrations of manganese and two samples (number 7: Sydney Airport and number 1: RCMP Office; Reserve Mines) have higher concentrations of priority elements (especially lead) than the recommended guidelines (>0.05 mg/l). These priority elements and the PAHs in the drinking water samples may have originated from the leaching of the individual coal seams within that part of the Sydney Basin. Other potential sources of these elements and PAHs (Power Plant disposal, Sydney Tar Pond, metalliferous rocks, hydrocarbon reservoir rocks) are not located close enough to the sampling sites of the water samples. Therefore, they are not considered the source of these elements and PAHs.  相似文献   
33.
The advent of chemical abrasion-isotope dilution thermal ionisation mass spectrometry (CA-IDTIMS) has revolutionised U–Pb dating of zircon, and the enhanced precision of eruption ages determined on volcanic layers within basin successions permits an improved calibration of biostratigraphic schemes to the numerical time-scale. The Guadalupian and Lopingian (Permian) successions in the Sydney, Gunnedah, Bowen and Canning basins are mostly non-marine and include numerous airfall tuff units, many of which contain zircon. The eastern Australian palynostratigraphic scheme provides the basis for much of the local correlation, but the present calibration of this scheme against the numerical time-scale depends on a correlation to Western Australia, using rare ammonoids and conodonts in that succession to link to the standard global marine biostratigraphic scheme. High-precision U–Pb zircon dating of tuff layers via CA-IDTIMS allows this tenuous correlation to be circumvented—the resulting direct calibration of the palynostratigraphy to the numerical time-scale highlights significant inaccuracies in the previous indirect correlation. The new data show: the top of the Praecolpatites sinuosus Zone (APP3.2) lies in the early Roadian, not the middle Kungurian; the top of the Microbaculispora villosa Zone (APP3.3) lies in the middle Roadian, not the early Roadian; the top of the Dulhuntyispora granulata Zone (APP4.1) lies in the Wordian, not in the latest Roadian; the top of the Didecitriletes ericianus Zone (APP4.2) lies in the first half of the Wuchiapingian, not the latest Wordian; the Dulhuntyispora dulhuntyi Zone (APP4.3) is exceptionally short and lies within the Wuchiapingian, not the early Capitanian; and the top of the Dulhuntyispora parvithola Zone (APP5) lies at or near the Permo-Triassic boundary, not in the latest Wuchiapingian.  相似文献   
34.
As the social, ecological and economic benefits of green buildings become more established, firms, especially professional service firms, are responding by adopting sustainable office space (SOS). Accelerating this uptake demands a nuanced appreciation of firms’ understandings of and motivations for adopting SOS. Through a qualitative study of professional service firms in Sydney, this paper brings together a decentred understanding of the contemporary firm drawn from the ‘new economic geographies’ approach and theories of corporate social responsibility to trace and interpret the diverse and overlapping motivations shaping the uptake of SOS amongst these firms. The firm is shown to be a site of plurality and agency, governed by multiple logics. Whilst motivations informed by economic logic remain persuasive and pervasive, the adoption of SOS is simultaneously informed by a wider palette of logics, including environmental and social logics. The paper argues that a decentred conceptualisation of the firm brings the multiplicity of firms’ orientations towards SOS into view and, in so doing, has the potential to inform a politics of intervention for steering firms towards more socially and environmentally sustainable behaviours.  相似文献   
35.
构造煤中煤层气扩散-渗流特征及其机理   总被引:2,自引:0,他引:2       下载免费PDF全文
煤层气产出一般要经过解吸、扩散和渗流三个阶段,而煤层气在变形较强的构造煤中的扩散过程不同于在原生结构煤或变形较弱的煤体中的扩散。外界压力的变化只是构造煤吸附与解吸整个过程的一种外在因素,构造煤的变形和结构变化以及吸附势场的转换才是构造煤吸附与解吸的内在因素,是导致解吸过程不可逆性的根本原因。当构造煤体与CH4等多元气体间的吸附平衡状态遭到破坏时,变形较强的构造煤在降压后会产生解吸滞后现象;而变形较弱的煤,分子结构中的气体会很快解吸,第一阶段是气体解吸作用,第二阶段是游离气体从微孔向较大孔隙扩散的过程,气体扩散速率主要由第二阶段决定。构造煤气体扩散机理主要是由孔隙形状、大小、连通性和多元气体性质和状态所决定的。韧性变形煤的微孔隙比较发达,所以韧性变形煤以Knudsen扩散为主,脆性变形煤的中、大孔隙所占比例较大,而且脆性变形煤的孔隙之间具有很好的连通性,所以脆性变形煤以Fick型扩散为主,脆-韧性变形煤以及接近脆-韧性变形煤的脆性变形煤和韧性变形煤均以过渡型扩散为主。在试井渗透率比较中,一定变形程度的脆性变形煤>韧性变形煤,脆性变形煤中以过渡孔为主,其余为微孔,测不出亚微孔和极微孔,脆性变形还增加了各孔隙之间的相互连通性。韧性变形煤中过渡孔比表面积所占比例下降,微孔和亚微孔增高,扩散主要发生在微孔和过渡孔中,所以韧性变形煤的试井渗透率低于脆性变形煤的试井渗透率。  相似文献   
36.
Microgeographies of Retailing and Gentrification   总被引:2,自引:0,他引:2  
It has long been argued that gentrification is a process of consumption as well as production but, in the main, analyses of consumption and gentrification have only tangentially or anecdotally considered the retail spaces of gentrified neighbourhoods. In this paper we investigate the nature of the retail landscapes of gentrification, using empirical evidence from Sydney, Australia. We point to micro retailscapes that differ between gentrified neighbourhoods that suggest a divergence of consumption practices between different groups of gentrifiers. These consumption practices are considered both in terms of their relations to identity (through food and the conception of the body) and to the spaces of the city. The paper concludes by drawing out the implications for future research on the consumption practices of the new middle class and the working class in an international context .  相似文献   
37.
The environment in which we live greatly influences our health. One particular factor that has been related to morbidity and mortality is dwelling crowding. A range of mechanisms have been proposed as links between dwelling crowding and disease, including increased exposures to allergens, respiratory irritants and infectious agents in crowded dwellings. While studies of dwelling crowding have been conducted in many locations around the world, this factor has received little attention in Australian health studies. We examine relationships between dwelling crowding and health in Sydney, using three case studies at the local government area (LGA) level within the Sydney Statistical Division. Dwelling and demographic data from the 1996 Australian census are used, along with four socio-economic indexes produced by the Australian Bureau of Statistics, and hospital inpatient data for the period 1 July 1994 to 30 June 1997 as the health indicator. Results suggest that dwelling crowding is a significant factor in certain diseases in Sydney. Asthma hospital separations are not correlated with dwelling crowding, although multiple linear regression analysis produces three models which include crowding and three of the socio-economic indexes as significant variables. Separations for bronchitis and emphysema, and all causes combined, are positively correlated with dwelling crowding. Dwelling crowding is strongly negatively correlated with all but one of the socio-economic indicators.  相似文献   
38.
39.
Non‐recognition is one of the key modes of re‐inscribing the Other. In Sydney's anti‐mosque politics this form of oppression was manifest as a discourse of absence. Sydney Muslims have been portrayed as non‐existent within, or external to, localities where mosques have been proposed. In these circumstances claims to belonging and citizenship by Sydney Muslims have been fundamentally injured. Census data are used to challenge the historical and contemporary constructions of Islamic absence in Australia. Sydney Muslims are a culturally diverse and somewhat disparate faith group. They are increasingly present in areas outside of the initial zones of residential focus. This diversity and dynamism is a substantial challenge for Islamic community building (Ummah) in Sydney and presents rich foci for further research.  相似文献   
40.
阐述了煤成油研究对挖潜和扩大石油的勘探范围,完善和发展石油勘探理论都具有重要的现实和理论意义,并从有机岩石学观点出发,对煤成不同的研究现状和进展进行了评述。  相似文献   
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