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101.
The genetic relationships between microenvironment of the Late Paleozoic peat-forming swamp and the sulfur contents of coal in North China have been studied by using coal-facies parameters involving gelification degree, tissue preservation index, vegetation index, transportation index, groundwater influence index, water medium indicator and swamp type index, etc. Among the various controlling factors of swamp microenvironment, swamp water medium elaborates a dominant action to sulfur accumulation in the marine-influenced coals; while coal-forming plant type, hydrodynamic state and water covering depth are more important to sulfur accumulation in the fresh water-influenced coals. Geological fractionation of sulfur isotopes reflects that sulfur accumulation experienced multi-stages evolution. Pyrite sulfurs formed earlier than organic sulfur and the sulfur isotopic δ34Sp shows lower values than organic sulfur isotopic δ34So. In the brine-influenced coals, sulfur accumulation processed relatively a long time span, the distribution of sulfur isotopes dispersed, and the coals are provided with high sulfur contents. In the fresh-water-influenced coals, sulfur accumulation occurred mainly at the syngenetic-penesyngenetic stage and the early diagenetic stage, and the total sulfur is lower and mainly composed of organic sulfur.  相似文献   
102.
The role of planning in Sydney's economic development since the mid-1970s is explored, focusing on its role in reducing spatial disparities across the region. Planning policies during the period of each State government--Labor (1976-88), Liberal-National (1988-95) and Labor (1995-present)--are reviewed. The paper analyses a hierarchy of factors underlying the relative failure of policies to lessen disparities, notably intra-government failure to produce effective policies, the influence of prevailing ideology, local institutions and political culture, and the wider context of globalisation and the mode of capitalist accumulation. Each of these has been significant in limiting planning's role in addressing uneven development across the region.  相似文献   
103.
Maltese symbolic and lived identities are examined to explore the changes that occur in cultural identity between generations and place of residence within metropolitan Sydney. The results are employed to problematise Sandberg's straight-line theory, that is, that ethnic identity will decline with each successive generation. Our results, exploring ethnic identity in both its symbolic and lived-experience forms, confirm arguments that global cities are not homogeneous territories, as implied by Sandberg, but rather sites of cultural difference. The results suggest that, regardless of place of residence or generation, the symbolic Maltese identities remain similar, combating the old, naive assimilationist assumption that all immigrants would quickly abandon their ethnic identity, and favouring arguments supporting hybrid identities. Similarly, results for Maltese identity as lived experience suggest that their Maltese identity is less important only for those second-generation Maltese living in census collection districts with less than 10 per cent of the population born in Malta.  相似文献   
104.
A suite of samples from the Funan Mine, N.E. China, has allowed a comparison to be made between hydrocarbon-rich coals and coaly shales. These are immature coals and the known geological history suggests that they have experienced only a mild geothermal history. Analyses of the di- and sesquiterpenoid components show that compounds based on the kaurane skeleton are absent unlike Australian brown coals; and the diterpenes isopimarane, pimarane and 16α (H)-phyllocladane relate to a different community of higher plants such as Pinaceae and Taxodiaceae from those recognized in Australian brown coals. A consideration of geochimical parameters and biomarker composition leads to the conclusion that the geolipid concentrations in the sample suite are environmentally determined. It is concluded, therefore, that 22R-17β (H),21β (H)-bishomohopanoic acid and the 22R-17α (H),21β (H)-homohopane, both predominant components in their respective classes, are derived from different sources. Labdanic acids have been identified in these coals. They are likely to be derived from resin constituents of the coal and not from microbial biomass. They could potentially be developed as a maturation parameter. Cis and trans isomers of a triaromatic hydrocarbon based on the oleanane skeleton which has been previously identified in Victorian brown coal are present in the Funan coals. The more oxidizing the environment the less advanced is the isomerization of cis to trans and again the environment of deposition is the controlling factor. This study emphasizes the importance of understanding pathways of early diagenesis for the interpretation of data derived from more mature samples.  相似文献   
105.
This paper presents an analysis of a neglected area of study by geographers; that of resident action groups. During the 1980s there has been a significant increase in the number of resident action groups throughout Sydney. Resident activism has influenced local planning processes, the location of noxious facilities and subsequent urban form. This has initiated important reactions by government at both the local and State levels. Urban collective activisms have been hypothesised as single‐issue, self‐serving nimby groups. However, RAGs are also empowering forces, in which women and men are introduced to the political structures and become engaged in protest and resistance that can challenge the social and spatial order. RAGs can, either singularly or cumulatively, force a re‐aligning of existing power relations, and they can necessitate changed modes of governance (or govern‐mentality).  相似文献   
106.
晚石炭世末期-三叠纪东澳大利亚的鲍恩-冈尼达-悉尼(Bowen- Gunnedah-Sydney)盆地系是位于拉克伦(Lachlan)褶皱带和新英格兰(New England)褶皱带之间的一个长条形的构造盆地。从北部的冈尼达(Gunnedah)到南部的巴特曼斯(Batemans)湾,悉尼盆地是鲍恩-冈尼达-悉尼盆地系南端的一个次级盆地。悉尼盆地的二叠系包括河流、三角洲、滨浅海沉积岩和火山岩地层。南悉尼盆地的西南部二叠系不整合覆盖于变形变质的拉克伦(Lachlan)褶皱带之上。二叠系由下部的塔拉特郎(Tallaterang)群、中部的肖尔黑文群(Shoalhaven Group)和上部的伊勒瓦拉煤系(Illawarra Coal Measures)组成。从晚石炭世末到中三叠世悉尼盆地经历了弧后扩张到典型的前陆盆地的不同阶段:弧后扩张阶段、被动热沉降阶段和挤压挠曲负载阶段。  相似文献   
107.
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   
108.
拉曼光谱能够反映碳材料结构的有序程度和结构缺陷,可用来表征高煤级煤—隐晶质石墨演化过程中结构变化。通过对受岩浆热变质影响的不同变形变质程度样品的拉曼参数与面网间距(d002)之间关系的研究表明:G峰位置与d002呈现阶梯变化,能较好地区分出石墨与高煤级煤,S2峰位、D1、G半峰宽与d002呈较好的线性关系;D1与G峰峰位差和半峰宽比随d002减小而减小,S2与S4峰的峰位差随d002减小先增大后减小,而其强度比及面积比逐渐增大;d002与拉曼参数关系显示两次明显的结构演化跃变,即无烟煤至变质无烟煤阶段,Rmax>6.5%、P(D1-G)<235 cm-1、P(S2-S4)>525 cm-1以及半峰宽比显著下降、La/Lc迅速降低,为芳构化、芳环缩合作用增强向芳环叠片拼叠转变;半石墨至石墨演化阶段,P(D1-G)、ID1/IG与AD1/AG显著降低,La、Lc迅速增加。以d002为标度能较好地反映煤结构在不同演化阶段的Raman光谱特征。   相似文献   
109.
Variability of chlorophyll (as an index of micro-algal abundance) between warm and cool seasons at different heights on (distances across) the shore was investigated on intertidal mudflats in warm-temperate Australia. Chlorophyll was measured using ratios of reflectances from field spectrometry and minimal fluorescence (F0) from PAM fluorometry to compare patterns obtained using these two methods. A single sampling period comprised 2 days of sampling, one for each mudflat, with 2 sampling periods nested within each month, 2 months within each of a cool and warm season in each of 2 years. Large differences in amounts of chlorophyll were found between the two mudflats, although spatial and temporal patterns of variation were generally similar. There were greater amounts of chlorophyll in the cooler months than in the warmer months in each location in each year, which contrasts with many of the patterns reported from elsewhere. There was more chlorophyll on the upper than on the lower shore and the increases from summer to winter were generally greater at the higher levels. Large variation in chlorophyll from week to week within each month demonstrated the need for adequate replication in studies of seasonal patterns of variability. Measurements made by a field spectrometer and a PAM fluorometer were largely consistent, but, at certain times, they showed an opposite pattern. The reasons for these differences were investigated further by looking at differences in other pigments, but the different results from the two methods could not to be explained by changes in composition of the micro-algal assemblage and, as yet, remain unexplained.  相似文献   
110.
煤成油油源对比问题讨论   总被引:3,自引:0,他引:3  
戴卿林  卢双舫 《地球化学》1996,25(4):324-330
通过吐哈盆地煤的低温排烃模拟实验及源岩与原油之间组分分析,发现煤与泥岩的排烃作用存在明显差异。煤成油在排驱过程中,由于地质色层作用使组分分布特征产生了明显变化而难以与母源对比。煤成油的油源对比不适宜引用以往"油一源必然相似"的原则。  相似文献   
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