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排序方式: 共有75条查询结果,搜索用时 31 毫秒
21.
Rezvandehy Mehdi Leung Juliana Y. Ren Weishan Hollands Ben Pan Guoai 《Natural Resources Research》2019,28(3):777-811
Natural Resources Research - Production forecasts are extremely sensitive to the spatial distribution of certain reservoir parameters, especially permeability, which controls fluid flow and... 相似文献
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de Jesús Arrieta Baldovino Jair dos Santos Izzo Ronaldo Luis Rose Juliana Lundgren Avanci Mônica Angélica 《Geotechnical and Geological Engineering》2021,39(6):4655-4657
Geotechnical and Geological Engineering - 相似文献
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Juliana Mansvelt 《New Zealand geographer》2012,68(3):187-200
Consumption practices involving disposal can provide important insights into how ‘being’ is accumulated. Analysis of 36 semi‐structured interviews with 13 individuals aged 59–70 in the Manawatu, Kapiti, Rangitikei and Horowhenua regions of the North Island in New Zealand illustrates how practices of gifting, ridding and passing on goods as legacy contribute to the production of familial and individual subjectivities. The research revealed that practices of disposal are performative, with both the absent presence of the objects placed away and the practices by which this occurs having agentic effects. The places that objects were assumed to occupy in the real and imagined lives of others and the moving of things away contributed to older adults' identities as caring parents, productive citizens and individuals of significance. Disposal practices consequently enabled participants to stabilise and order parent and child relations and one's relative position in the life course. 相似文献
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Integrated assessment of smallholder farming’s vulnerability to drought in the Brazilian Semi-arid: a case study in Ceará 总被引:1,自引:0,他引:1
Diego Pereira Lindoso Juliana Dalboni Rocha Nathan Debortoli Izabel Ibiapina Parente Flávio Eiró Marcel Bursztyn Saulo Rodrigues-Filho 《Climatic change》2014,127(1):93-105
Smallholder farming is among the most vulnerable sectors due to its great social and economic sensitivity. Despite future climate change, current climate variability is already an issue of concern that justifies adaptation efforts. In Brazil, the Semi-Arid Region is a climate hotspot, well known for both historic socioeconomic setbacks, and agriculture failures caused by dry spells and severe droughts. In 2010, the Brazilian government enacted the National Policy on Climate Change, which states as one of its key goals the identification of vulnerabilities and the adoption of adequate measures of adaptation to climate change. The improvement of vulnerability assessment tools is a response to the growing demand of decision makers for regular information and indicators with high spatial and temporal resolution. This article aims at undertaking a comparative assessment of smallholder farming’s vulnerability to droughts. An integrated assessment system has been developed and applied to seven municipalities located in the Brazilian Semi-Arid Region (within the State of Ceará). Results show regional vulnerability contrasts driven by institutional and socioeconomic factors, beyond climatic stressors. 相似文献
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Marcelo S. de la Fuente Aldo M. Umazano Juliana Sterli José L. Carballido 《Cretaceous Research》2011,32(4):527-537
A new chelid species (Prochelidella cerrobarcinae nov. sp.) are described from the Aptian-Albian? Puesto La Paloma Member, Cerro Barcino Formation, northern of Chubut Province, Argentina. The basal section of this member, which bears the turtle remains, is composed of tuffaceous mudstones with plane parallel lamination, asymmetrical ripples and a chert intercalation suggesting sub-aqueous deposition in a relatively shallow lacustrine environment. Pr. cerrobarcinae nov. sp. is represented by post-cranial remains of several specimens that not only represents the oldest pleurodiran chelid record in the world but, together with the chelid remains of Albian Lightning Ridge, New South Wales, Australia, indicates that chelid diversification began well before the final fragmentation of southern Gondwana. 相似文献
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Juliana?TrochEmail authorView authors OrcID profile Ben?S.?Ellis Axel?K.?Schmitt Anne-Sophie?Bouvier Olivier?Bachmann 《Contributions to Mineralogy and Petrology》2018,173(7):54
The Island Park-Mount Jackson series in the Yellowstone volcanic field, Wyoming (USA), is a suite of rhyolitic domes and lavas that erupted between the caldera-forming eruptions of the Mesa Fall Tuff (1.3 Ma) and the Lava Creek Tuff (0.6 Ma). Combined zircon U/Pb geochronology, Raman spectroscopy, oxygen isotopic and trace elemental compositions document storage conditions of these magmas between consecutive supereruptions. Based on comparison with co-erupted melt compositions and textural criteria, four zircon compositional groups are identified that record different stages along a continuous magmatic evolution from trace element-poor rhyolite at high temperatures to extremely fractionated rhyolite where zircon trace elements are highly enriched (e.g., >?1000 ppm U). These latter zircon domains are dark in cathodoluminescence images and show broadened Raman peaks relative to near-endmember zircon, indicating that substitution of non-stoichiometric trace elements into zircon leads to distortion of the crystal lattice. Some of these zircon domains contain inclusions of U-Th-REE-phases, likely originating from coupled dissolution–reprecipitation of metastable trace element-rich zircon in the presence of a fluid phase. Rhyolite-MELTS simulations indicate that at the conditions required to produce the observed enrichment in trace elements, a fluid phase is likely present. These findings illustrate that zircons can be assembled from a variety of co-existing magmatic environments in the same magma reservoir, including near-solidus volatile-rich melts close to the magmatic–hydrothermal transition. 相似文献
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Juliana Maantay 《The Professional geographer》2013,65(3):406-408
The North Carolina Hispanic population has grown at a rapid pace in recent years. Before 1980, the majority of Hispanics in North Carolina were engaged primarily in migrant agricultural work. Hispanics who are part of the new influx are arriving in urban areas and are working at nonagricultural pursuits. Previous research and anecdotal evidence suggest that Hispanic newcomers come from other U.S. jurisdictions and from abroad. Labor migration occurs in response to demand for labor, and labor demand is meditated by employers’ preferences and hiring practices. However, focusing solely on employer demand for labor ignores the role of past U.S. immigration policy and the large growth in services employment in the Sunbelt that have fueled the Hispanic in–migration. This research project explored the attitudes and recruiting behavior of employers in the Triangle region of North Carolina. A newspaper content analysis was undertaken, and interviews were conducted with selected intermediaries and a group of employers. Qualitative analysis of the data collected revealed that these employers utilize the social networks of their immigrant Hispanic employees to recruit new workers. They also use a variety of other recruiting methods to recruit Hispanics both locally and from abroad. If this practice is widespread, it may be fueling the influx of Hispanic immigrants to North Carolina. Employers interviewed extolled the work ethic of Hispanic workers and often bypassed native–born workers, whom they felt were inferior employees. These findings have ramifications for future immigration policy and for the success of welfare–to–work programs. Employer demand for labor is one factor that must be considered when formulating new immigration policy. 相似文献
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