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1.
As inter-generational support is the primary source of support for the Chinese elderly in rural areas, such support is likely to affect their physical and psychological health. This paper investigates the effects of four types of inter-generational support on the mortality risk of the elderly in Anhui Province. Results showed that mortality risk was influenced significantly only by receiving household support. Financial support and personal care had no effect. Results also indicated that household and emotional support were effective in reducing mortality when delivered at closer proximity, suggesting that quality of support may be enhanced by co-residence and ready access to children. Conclusions about the health benefits of tangible forms of support need to be tempered by an understanding that poor health predisposes inter-generational co-residence, and that the quality of household assistance and emotional support may be sensitive to the geographic distance between older parents and their adult children in rural China.  相似文献   
2.
In recent years, H/V measurements have been increasingly used to map the thickness of sediment fill in sedimentary basins in the context of seismic hazard assessment. This parameter is believed to be an important proxy for the site effects in sedimentary basins (e.g. in the Los Angeles basin). Here we present the results of a test using this approach across an active normal fault in a structurally well known situation. Measurements on a 50 km long profile with 1 km station spacing clearly show a change in the frequency of the fundamental peak of H/V ratios with increasing thickness of the sediment layer in the eastern part of the Lower Rhine Embayment. Subsequently, a section of 10 km length across the Erft-Sprung system, a normal fault with ca. 750 m vertical offset, was measured with a station distance of 100 m. Frequencies of the first and second peaks and the first trough in the H/V spectra are used in a simple resonance model to estimate depths of the bedrock. While the frequency of the first peak shows a large scatter for sediment depths larger than ca. 500 m, the frequency of the first trough follows the changing thickness of the sediments across the fault. The lateral resolution is in the range of the station distance of 100 m. A power law for the depth dependence of the S-wave velocity derived from down hole measurements in an earlier study [Budny, 1984] and power laws inverted from dispersion analysis of micro array measurements [Scherbaum et aL, 2002] agree with the results from the H/V ratios of this study.  相似文献   
3.
The Indian state of Kerala leads the demographic transition and characteristically showcases emigration of predominantly male adult children, leaving behind parents, spouses and children. When men emigrate, gendered contexts burden women, especially spouses and daughters-in-law, with caregiving duties including elder care. Employing the social exchange perspective and drawing on in-depth interviews of left-behind caregivers to older adults in emigrant households, we explore reciprocal motives, expectations and perceptions of burden. Findings resonate gendered expectations of care and social sanction that ensure women do much of the caregiving. Daughters-in-law sacrificed careers and endured separation from husbands to transition into caregiving roles, costs borne to effectuate their husband's filial role. Perceived non-reciprocity, unbalanced exchanges and unmet expectations increased perceptions of burden for caregivers. Temporary financial autonomy could hardly alleviate perceptions of burden among women caregivers who perceived emotional and functional support exchanges from husbands, older adults themselves or other family members as supportive.  相似文献   
4.
Potential of palaeofluid analysis for understanding oil charge history   总被引:2,自引:0,他引:2  
J. PARNELL 《Geofluids》2010,10(1-2):73-82
Fluid inclusion data, particularly the distribution of hydrocarbon fluid inclusions and their chemistry, can provide insights into oil charge in a petroleum-prospective region. Examples from the UK Atlantic margin show how we can understand thermal regime, timing and chemistry of oil charge. Data from the UK Atlantic margin based on fluid inclusion temperature profiles shows anomalously high temperatures which are highest at the top of the Triassic–Eocene sequence. This is interpreted as a product of hot fluid flow, probably reflecting hydrothermal activity related to intrusion of sills at depth. The preservation of high temperatures also implies rapid migration from depth through fracture systems. Ar–Ar analysis of oil-bearing K-feldspar cements, and petrographic studies of oil inclusion distribution help delimit timing and migration pathways for the hot fluid charge and later fluid migration events. Coupled with compositional data for oils measured destructively (organic geochemistry) or non-destructively (fluorescence), these approaches allow the development of oil charge histories based on real data rather than theoretical modelling.  相似文献   
5.
The pre-Magdalenian phase of the Côa River Valley open-air rock art is mostly distributed at the boundary between the rocky valley slopes and the floodplain that correspond to the most favourable geomorphological setting for the preservation of pecked and deeply superposed engravings of the most famous artistic phase of the area. The natural vertical panels of the engraved art located at this geomorphological interface have suffered weathering during two cold events of the Lateglacial. They were buried by several colluvial and alluvial deposits. The reconstruction of the sedimentary and archaeological context of the CôaRiver Valley engraving permits a better assessment of the preservation processes and interpretation of Palaeolithic open-air rock art.  相似文献   
6.
7.
Abstract:

Concern has been growing recently in China about the well-being of children, women and the elderly “left behind” on the farm when family members leave the village in search of waged work. Increasingly, the left-behind are portrayed in academic and policy discourse as a “vulnerable group” of passive dependants, sidelined by modernisation and abandoned by their families. This paper challenges this discourse, arguing that while attention to the well-being of the left-behind is vital, there is an urgent need for a shift in focus from their vulnerability to their agency. The paper focuses on the agency of left-behind women between the ages of 50 and 80. It aims, first of all, to point the way toward an empirically richer understanding of the social construction of older women’s agency and well-being. The second aim of the paper is to suggest how different conceptualisations of “agency” and “older women” might contribute to more ethical and politically effective strategies for development and the improvement of women’s well-being. To further these two aims, the paper draws on fieldwork conducted in rural Ningxia, north-western China, and on critiques of the “capability approach” to development expounded by Amartya Sen and Martha Nussbaum.  相似文献   
8.
B. Jung  G. Garven  J. R. Boles 《Geofluids》2014,14(2):234-250
Fault permeability may vary through time due to tectonic deformations, transients in pore pressure and effective stress, and mineralization associated with water‐rock reactions. Time‐varying permeability will affect subsurface fluid migration rates and patterns of petroleum accumulation in densely faulted sedimentary basins such as those associated with the borderland basins of Southern California. This study explores the petroleum fluid dynamics of this migration. As a multiphase flow and petroleum migration case study on the role of faults, computational models for both episodic and continuous hydrocarbon migration are constructed to investigate large‐scale fluid flow and petroleum accumulation along a northern section of the Newport‐Inglewood fault zone in the Los Angeles basin, Southern California. The numerical code solves the governing equations for oil, water, and heat transport in heterogeneous and anisotropic geologic cross sections but neglects flow in the third dimension for practical applications. Our numerical results suggest that fault permeability and fluid pressure fluctuations are crucial factors for distributing hydrocarbon accumulations associated with fault zones, and they also play important roles in controlling the geologic timing for reservoir filling. Episodic flow appears to enhance hydrocarbon accumulation more strongly by enabling stepwise build‐up in oil saturation in adjacent sedimentary formations due to temporally high pore pressure and high permeability caused by periodic fault rupture. Under assumptions that fault permeability fluctuate within the range of 1–1000 millidarcys (10?15–10?12 m2) and fault pressures fluctuate within 10–80% of overpressure ratio, the estimated oil volume in the Inglewood oil field (approximately 450 million barrels oil equivalent) can be accumulated in about 24 000 years, assuming a seismically induced fluid flow event occurs every 2000 years. This episodic petroleum migration model could be more geologically important than a continuous‐flow model, when considering the observed patterns of hydrocarbons and seismically active tectonic setting of the Los Angeles basin.  相似文献   
9.
J. S. BELL  S. E. GRASBY 《Geofluids》2012,12(2):150-165
All available information relevant to in situ stress orientations and magnitudes in the Western Canadian Sedimentary Basin (WCSB) were examined to provide a better understanding of how regional stress fields may affect geothermal development. The smallest principal stress is horizontal over most of the Western Canadian Sedimentary Basin, and it varies in magnitude across the region. Horizontal stress trajectories show that SHmax axes are generally aligned SW–NE. A total of 1643 measurements of microfracture and minifracture closure pressures, leak‐off pressures and fracture breakdown pressures have been harnessed to map SHmin gradients across the basin at depths of 156–500, 500–1000, 1000–4185 and 2000–4185 m. Vertical stress magnitudes, calculated in 91 wells, showed that at constant depth, SV increases towards the Canadian Rocky Mountains. Resultant regional stress maps show consistent trends in orientation of stress axes. As a result, predictions can be made that propagation axes of subsurface hydraulic fractures will be dominantly SW–NE, except over the Peace River Arch area, where they will trend more towards SSW–NNE. Engineered geothermal systems in the WCSB can be optimised by drilling horizontal wells parallel to SHmin.  相似文献   
10.
This study examines links between migration status and location of adult children and measures associated with the well-being of older parents. Data come from older adults born between 1940 and 1950 living in a region in northwest Cambodia near the Thai border with good access to Phnom Penh. Analyses are conducted from the perspectives of the older adult and adult children. Results show that high rates of out-migration do not leave their older parents without alternative means of support. Migrant children often remain in contact by telephone. Most adult children remit money to their parents, but the majority of remittances are small. While large remittances are atypical, adult children living in Phnom Penh or across the border in Thailand are more likely to provide substantial amounts. The analysis presents a picture of an area where people are on the move but families still share resources and time with older adults.  相似文献   
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