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81.
中国煤成油研究进展和展望 总被引:2,自引:1,他引:2
中国煤和含煤岩系内石油的发现是在50 ̄60年代,而提出应在我国进行煤和含煤岩成油问题的研究是80年代初,自提出煤成油问题以来短短的十余年时间里,不仅在有机岩石学,煤成油地球化学,热模拟实验和煤成油综合研究等煤和含煤岩系成油理论上取得了进展,而且在油勘探的实践上,在吐鲁番和彩南取得了重要的进展。 相似文献
82.
ABSTRACTMuch has changed since the first mapping of single-sex couples and families from the 2006 Australian census. An increasing willingness to allow their identification in the census has accompanied increasing public acceptance of same-sex couples culminating in significant support for legalising same-sex marriage in a 2017 national survey. Technological advances permit complex cross-tabulations of Australian census data and more detailed characterisations of same-sex couples. New geographies differentiate between male and female couples with children, showing same-sex couples are not just a feature of some inner-city areas, though these remain important, but also of suburban, regional and some rural areas. Drawing on the 2016 census, contemporary geographies of same-sex couples with and without children in Australia and changes over the past decade in Sydney are analysed at a time of increased interest in this demographic. 相似文献
83.
低变质煤的有机地球化学指标,如“A”/Cor,“H”/Cor,IH,T(max)OEP,Pr/Ph,S1+S2,C3-菲/总烷基菲等随其在泥炭化过程中经受的氧化还原作用程度的变化而呈规律性变化,显示了氧化还原作用的各种特征.氧化作用以脱去一个至多个碳原子的脱羧基作用或断裂作用的形式,改变正烷烃,类异戊二烯烷烃和烷基菲的组成。并在其对残余部分性质所给予的影响的意义上,可被视为一种“超前煤化作用”。还原作用促进有机质向烃转化,随还原作用加深而发生的镜质组更加富氢的变化比镜质组数量的变化更能提高煤的产烃潜量。只有在查明了煤氧化还原程度的前提条件下,应用这些指标评价成熟度才可能更为准确。 相似文献
84.
Lynette C. McLoughlin 《The Australian geographer》2000,31(2):183-208
Described by Governor Phillip as 'the finest harbour in the world', Sydney Harbour was affected by accelerated sedimentation very soon after settlement in 1788. Dredging began in 1842 to deal with the problems caused by sedimentation and to enhance foreshore amenity. By the end of the nineteenth century, dredging was also excavating the bottom of the Harbour and its bays to accommodate larger ships with deeper draughts, and dredged sediment was increasingly used to reclaim mudflats or marshes deemed unhealthy or unsightly, thereby creating additional useful waterfront land. There was virtually continuous dredging in some part or other of the Harbour and its tributaries for almost 140 years. With increasing costs and mounting environmental concerns, dredging is now intermittent, and carried out largely to facilitate navigation for specific projects, despite continued sedimentation. While there was an early lack of understanding of the Australian environment and the impact of clearing on soils, the causes of increased sedimentation had been documented by the 1860s. However, measures to seriously address causes were not introduced until late in the twentieth century. This paper briefly outlines the development of the Sydney estuary to 1788, considers the impact of settlement in accelerating sedimentation, traces the development of dredging and reclamation, and discusses their significance for a number of areas of current research and environmental management, as well as to social and economic history. Within the limitations of the data available, annual sediment dredged, annual expenditure, cost per tonne, and areas reclaimed by dredging and filling are included. 相似文献
85.
《Urban geography》2013,34(2):92-119
What makes places different from one another in the context of globalization? An analysis of 17 emblematic practices in two global cities, Los Angeles and Sydney, provides the empirical basis for answering this question. Evidence from the built environment, the social geography, and the patterns of disorder in the inner cities of these two global places shows that these cities were more alike in the late 1960s than they are today. The differentiation of the two places has increased as the effects of globalization have become more pervasive. The evidence presented in this paper suggests that there is nothing inherent in contemporary globalization that requires global cities to have inner city slums, ghettoes, massive homelessness, residential disinvestment, White flight, relict or suboptimally-utilized brownfields, illegal prostitution, a war on drugs, public spaces awash with guns, and so forth. Places are viewed here as constellations of distinctive practices configured in particular geographical settings at the intersection of specific conjunctures of historical change. Places matter in the epoch of globalization as differentially embedded, bounded particularities consisting of a mixed assortment of human practices forming causally consequential fields of effects. 相似文献
86.
Charishma Ratnam 《Urban geography》2013,34(8):1198-1209
Australia publicly espouses its multiculturalism as a key component of its national identity. In this paper, I argue that despite the importance of multiculturalism to Australia’s identity, political decisions and discourse has muddied its remit with respect to humanitarian migrant intake programs and outcomes. Australia’s history of selective migrant intake and restrictive refugee policy continues the Othering of past policies into contemporary settings. Refugee policy has become a political football. During the most recent national election campaign (May 2019), the plight of sick and ill refugees, currently housed offshore in detention centers, was used as a political pawn. Lost amid this political rhetoric were the traumatic narratives of forced migrants resettling in Australia’s cities. Without possibility for a loud voice in public discourse, there is little opportunity for more Australians to understand how refugees experience detention centers, struggle to attain residency visas, and make “home” in multicultural Australia. I draw on research with Sri Lankan refugees in Sydney to give voice to these micro-level, place-based experiences of vulnerable arrivals. These stories, I think, can (re)shape and enrich Australia’s multicultural identity because they challenge us to not only accept difference but recognize the circumstances through which Australia’s diversity seeds its narrative. 相似文献
87.
Moving foreign human and financial capital through landed property is not a new phenomenon in Sydney. It is a recurring geopolitical strategy that is replete with intercultural tension and deep colonial roots. In contemporary Australia, there is an assumption in public policy and media rhetoric that there is a high level of public concern about foreign investment. However, there is little empirical data that examines public perceptions. In this study, we are interested in whether the dominant voices in this debate represent broad public views about this issue. We sought to fill this gap by conducting a survey of almost 900 Sydney residents, looking at their perceptions of foreign and Chinese investment. We find high levels of public concern and discontent about foreign investment amongst Sydneysiders, with Chinese investors being a key target of this discontent. In the context of high housing prices in Sydney, there were widely held concerns about housing affordability. Survey respondents had a sophisticated understanding of what influences house prices, but with an overemphasis on the role of foreign investment. There is a general lack of support for policy that encourages foreign investment, and a lack of confidence in how the government is regulating foreign investment. Half of our participants reported that they would not welcome Chinese foreign investment in their suburb. 相似文献
88.
Cities were once thought to be crucibles of secularisation, where the retreat from religion and its expression would be most pronounced. This decline in faith was linked to the heightened levels of heterogeneity and cosmopolitanism within cities. However, there is recent evidence of both the continuation and of the recession of the secularisation process in contemporary Western societies, with the mix and pace of these trends being quite unique to different countries. Significantly, this combination of processes has been argued to be part of a ‘post-secularist’ paradigm. Drawing on census data, this paper examines the spatial patterns of religious affiliation and non-belief in the Australian city of Sydney. Sydney has divergent geographies of faith and non-faith indicating the spatial multiplicities of religious belief. The decrease in Christianity in some areas of the city has been matched by an increase in non-Christian faiths, while in other areas there has been little change. Some parts of the city—especially those areas with a strong mix of affluence, diversity and cosmopolitanism—betray the strongest levels of secularisation and the retreat of faith. At least five geographies of faith and non-belief are recognisable within Sydney. While post-secularisation has been recognised as internationally uneven, this research demonstrates that it is also uneven across a world city like Sydney. The Sydney variations in (de)secularisation reflect city-based effects, including the historic and contemporary patterns of immigrant settlement, established and emerging religious communities, the segmented geographies of class and affluence, and the development of zones of cosmopolitanism. The findings point to the need for further research on the micro-geographies of religious belief and non-belief and community relations, and the on links between religious communities and civil society. 相似文献
89.
Many hydrological and agricultural studies require simulations of weather variables reflecting observed spatial and temporal dependence at multiple point locations. This paper assesses three multi-site daily rainfall generators for their ability to model different spatio-temporal rainfall attributes over the study area. The approaches considered consist of a multi-site modified Markov model (MMM), a reordering method for reconstructing space–time variability, and a nonparametric k-nearest neighbour (KNN) model. Our results indicate that all the approaches reproduce adequately the observed spatio-temporal pattern of the multi-site daily rainfall. However, different techniques used to signify longer time scale observed temporal and spatial dependences in the simulated sequences, reproduce these characteristics with varying successes. While each approach comes with its own advantages and disadvantages, the MMM has an overall advantage in offering a mechanism for modelling varying orders of serial dependence at each point location, while still maintaining the observed spatial dependence with sufficient accuracy. The reordering method is simple and intuitive and produces good results. However, it is primarily driven by the reshuffling of the simulated values across realisations and therefore may not be suited in applications where data length is limited or in situations where the simulation process is governed by exogenous conditioning variables. For example, in downscaling studies where KNN and MMM can be used with confidence. 相似文献
90.
On the basis of a numerical simulation, Klose [Earth Planet. Sci. Lett. 256: 547–553 (2007)] proposed that the MW = 5.2–5.6 earthquake that nucleated beneath Newcastle (New South Wales, Australia) at 10.30 AM December 28, 1989 (AEST), was the result of 200yr of coal mining in the region. We argue here that Klose's [Earth Planet. Sci. Lett. 256: 547–553 (2007)] ultimate conclusion is not supported by his own model or by available geological and seismic data. In particular, the 1989 Newcastle earthquake was not anomalous with respect to regional seismic activity. 相似文献