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101.
Tu m'as repondu     
ABSTRACT

Literal biblical interpretation advocates the view that at the outset of the paradise story Adam and Eve were only banned to eat of the tree of knowledge. The present paper challenges this view through an economic, ra-tional choice interpretation and the application of a self-interested decision calculus (model of economic man). I mount the thesis that, on grounds of a rational choice reconstruction, Adam and Eve must have been implicitly banned from the outset not to eat of the tree of life, despite no explicit ban be-ing stated in Genesis. The paper argues for the validity and insightfulness of such a rational choice analysis of the paradise story, which considerably clari-fies the conceptual logic and structure of the Eden story.  相似文献   
102.
ABSTRACT

We investigate the inherent characteristics of 2D basins subjected to vertically propagating P-SV waves using the finite difference approach. The ratio of fundamental frequencies between an inhomogeneous basin (f0) and its equivalent flat layers (fh) is found to be a function of both its outer overall geometry and inner geometric formation. 2D resonance can occur in inhomogeneous basins under certain conditions, and the f0/fh can be used to demarcate deep from shallow basin behaviors. With other conditions remaining the same, changing a basin from homogeneity to inhomogeneity results in a lower f0/fh and makes 2D resonance less likely to occur.  相似文献   
103.
The aim of this study was to determine the process–structure–property relationships between the pre‐ and post‐CO2 injection pore network geometry and the intrinsic permeability tensor for samples of core from low‐permeability Lower Triassic Sherwood Sandstone, UK. Samples were characterised using SEM‐EDS, XRD, MIP, XRCT and a triaxial permeability cell both before and after a three‐month continuous‐flow experiment using acidic CO2‐rich saline fluid. The change in flow properties was compared to those predicted by pore‐scale numerical modelling using an implicit finite volume solution to the Navier–Stokes equations. Mass loss and increased secondary porosity appeared to occur primarily due to dissolution of intergranular cements and K‐feldspar grains, with some associated loss of clay, carbonate and mudstone clasts. This resulted in a bulk porosity increase from 18 to 25% and caused a reduction in mean diameter of mineral grains with an increase in apparent pore wall roughness, where the fractal dimension, Df, increased from 1.68 to 1.84. All significant dissolution mass loss occurred in pores above c. 100 μm mean diameter. Relative dilation of post‐treatment pore area appeared to increase in relation to initial pore area, suggesting that the rate of dissolution mass loss had a positive relationship with fluid flow velocity; that is, critical flow pathways are preferentially widened. Variation in packing density within sedimentary planes (occurring at cm‐scale along the ‐z plane) caused the intrinsic permeability tensor to vary by more than a factor of ten. The bulk permeability tensor is anisotropic having almost equal value in ‐z and ‐y planes but with a 68% higher value in the ‐x plane (parallel to sedimentary bedding planes) for the pretreated sample, reducing to only 30% higher for the post‐treated sample. The intrinsic permeability of the post‐treatment sample increased by one order of magnitude and showed very close agreement between the modelled and experimental results.  相似文献   
104.
Various thermodynamic properties of H2O that are defined as pressure or temperature derivatives of some other variable, such as isothermal compressibility (β, pressure derivative of density), isobaric thermal expansion (α, temperature derivative of density), and specific isobaric heat capacity (cf, temperature derivative of enthalpy), all show large magnitudes near the critical point, reflecting large variations in fluid density and specific enthalpy with small changes in temperature and pressure. As a result, mass (related to fluid density) and energy (related to fluid enthalpy) transport in this PT region are sensitive to changing PT conditions. Addition of NaCl to H2O causes the region of anomalous behavior, here defined as the critical region, to migrate to higher temperatures and pressures. The critical region is defined as that region of PT space in which the dimensionless reduced susceptibility  ≥ 0.5. When NaCl is added to H2O, the critical region migrates to higher temperature and pressure. However, the absolute magnitudes of thermodynamic properties that are defined as temperature and/or pressure derivatives (α, β, and cf) all decrease with increasing salinity. Thus, the mass and energy transporting capacities of hydrothermal fluids in the critical region become less sensitive to changing PT conditions as the salinity increases. For example, quartz solubility can be described as a function of fluid density, and because density becomes less sensitive to changing PT conditions as salinity increases, quartz solubility also becomes less sensitive to changing PT conditions as fluid salinity increases. Similarly, fluxibility describes the ability of a fluid to transport heat by buoyancy‐driven convection, and fluxibility decreases with increasing salinity. Results of this study show that the mass and energy transport capacity of fluids in the Earth's crust are maximized in the critical region and that the sensitivity to changing PT conditions decreases with increasing salinity.  相似文献   
105.
有研究表明,相较于传统的干燥技术,利用超临界CO2流体干燥技术对出土饱水竹木器进行干燥具有周期短、变形小的优势。与出土饱水竹木器相比,海洋出水木质文物除了含水率高外,还含有较多的难溶性盐分,在文物的长期保存和展览中,盐分与水分、空气、文物本身进行化学反应会加速文物的老化和腐蚀。因此,本研究以“南海Ⅰ号”船体的部分构件为研究对象,开展了将超临界CO2流体干燥技术应用于海洋出水木质文物的探索实验研究。实验结果表明,在温度40 ℃,压力20 MPa的条件下,超临界CO2流体干燥海洋出水木质文物效果明显,样品的三向干缩率均低于或者接近健康木材阴干的三向干缩率;含水率大幅度下降,经过超临界技术干燥后不需再做其他干燥处理就能满足文物保存的要求。文物干燥前后含盐率的测量结果表明,此干燥技术还具有明显脱盐的效果。  相似文献   
106.
The ‘Movius–Schick hypothesis’ claims that an absence of Levallois (Mode 3) technologies in East Asia is due to the lack of a strong ancestral Acheulean (Mode 2) tradition in that region. Hence, this hypothesis is based on the assumption that similarities between Acheulean handaxes and Levallois cores can be interpreted as being phylogenetically homologous (i.e. due to common technological ancestry) as opposed to being homoplasic (i.e. due to convergent technological evolution). Here, the phylogenetic basis of this hypothesis is tested using a formal cladistic procedure. Under the framework of an ‘iterative’ approach to phylogenetic analysis, a series of post-hoc tests and re-evaluations of results follow the initial cladistic analysis. Results of these combined analyses indicate that morphological similarities between Mode 2 Acheulean handaxes and Mode 3 Levallois cores can, most parsimoniously, be seen as phylogenetically homologous. Hence, these results support the tenets of the ‘Movius–Schick’ hypothesis in suggesting that a lack of Levallois industries in East Asia may be due to the paucity of an ancestral Acheulean tradition in that region. The implications of these phylogenetic analyses for the concept of Palaeolithic ‘Modes’ are discussed. It is further suggested that low demographic levels (i.e. small effective population sizes) in East Asia may have constrained the technological phylogenetic trajectory of East Asia compared with that seen in other regions of the Old World during the Lower Palaeolithic. In addition, it is hoped that several methodological issues discussed here will contribute to the growing field of cultural phylogenetic analysis.  相似文献   
107.
One of the critical factors that control the efficiency of CO2 geological storage process in aquifers and hydrocarbon reservoirs is the capillary‐sealing potential of the caprock. This potential can be expressed in terms of the maximum reservoir overpressure that the brine‐saturated caprock can sustain, i.e. of the CO2 capillary entry pressure. It is controlled by the brine/CO2 interfacial tension, the water‐wettability of caprock minerals, and the pore size distribution within the caprock. By means of contact angle measurements, experimental evidence was obtained showing that the water‐wettability of mica and quartz is altered in the presence of CO2 under pressures typical of geological storage conditions. The alteration is more pronounced in the case of mica. Both minerals are representative of shaly caprocks and are strongly water‐wet in the presence of hydrocarbons. A careful analysis of the available literature data on breakthrough pressure measurements in caprock samples confirms the existence of a wettability alteration by dense CO2, both in shaly and in evaporitic caprocks. The consequences of this effect on the maximum CO2 storage pressure and on CO2 storage capacity in the underground reservoir are discussed. For hydrocarbon reservoirs that were initially close to capillary leakage, the maximum allowable CO2 storage pressure is only a fraction of the initial reservoir pressure.  相似文献   
108.
This paper identifies external factors affecting the capacity of Australia's now‐formalised 56 regional natural resource management (NRM) bodies and their community‐based Boards to meet planning and management responsibilities. It demonstrates that little is known about the basic capacity‐related characteristics of NRM regions, despite the lengthy and elaborate process of regionalism that Australia has embarked upon, with its associated and substantial devolution of responsibilities and resources. A suite of indicators is used to develop an ‘exploratory’ capacity typology of NRM regions. The ten regional ‘types’ identified are found to attract varying budget allocations under the Natural Heritage Trust Extension and National Action Plan for Salinity and Water Quality. There are indications that State and regional interests within and outside NRM can significantly influence the distribution of resources. An examination of resources allocated to capacity‐building activities shows significant differences between regions in the scale of resources allocated (0–96% of total budget). The paper argues the case for intervention to reduce the gap between ‘have’ and ‘have not’ regions, and for further exploration of disparities in the allocation of resources to capacity‐building activities. Clarification is needed of the extent to which capacity‐building activities adequately target regional NRM bodies and their Boards.  相似文献   
109.
Eastern Sicily (southern Italy) is characterised by the presence of many natural gas emissions (mofettes, mud volcanoes). These gases are mostly carbon dioxide and methane, with minor amounts of helium, hydrogen, carbon monoxide and hydrocarbons. In this study, the extent and orientation of soil gas anomalies (He and CO2) were investigated on a wide area (approximately 110 km2) located just SW of Mt. Etna. From a structural point of view, this area lays on a typical foredeep–foreland system that marks the boundary between the southern part of the Eurasian plate and the northern part of the African plate in the central Mediterranean. No tectonic structure was revealed in this area by surface geological surveys. Very high soil emissions were found, and their spatial pattern reveals the existence of some active faults all directed about N50°E. This direction coincides with that of two major fault systems that cut eastern Sicily and are evident, respectively, NE and SW of the study area. Soil gas data suggest that these fault systems are the expression of a single continuous structural line which is probably responsible for the past and present magma uprise in eastern Sicily. Isotopic values of carbon of CO2 suggest a minor contribution of organic carbon. Moreover, in the highest degassing sites the isotopic values of He found in association with CO2 (He abundance = 11–70 p.p.m.; R/Ra between 6.0 and 6.2) suggest that both gases are mantle derived. The extent of the areas affected by high gas emissions and the amounts of deep CO2 emitted in the investigated area (several hundred tonnes per day) may provide additional supporting evidence of a mantle upwelling taking place beneath this region.  相似文献   
110.
“石屿二号”沉船遗址位于西沙群岛石屿东侧的珊瑚礁石上,是西沙群岛海域一处重要水下文化遗存。该遗址出水了青花、卵白釉、白釉、青灰釉、酱釉等多种瓷器,是探索古代海上丝绸之路和外销瓷贸易的关键窗口。虽然前人通过青花瓷器类型学分析确定了遗址的相对年代,但由于未发现船体痕迹无法进行碳十四测年,而热释光测年方法则为确定遗址的绝对年代提供了一种替代手段。为了探究该遗址出水青花瓷器的热释光性质及年代,本研究利用前剂量饱和指数法对16件青花瓷片进行了古剂量测试。使用电感耦合等离子体质谱仪(ICP-MS)和电感耦合等离子体发射光谱仪(ICP-OES)分析样品的放射性元素U、Th、40K的含量。在剂量率的计算过程中综合考虑了样品的经纬度、埋藏深度、含水率以及放射性元素含量等参数,并首次使用综合矿物分析(TIMA)揭示了瓷胎中的石英粒径分布情况,以提高剂量率计算的准确度。热释光年代结果表明,这批青花瓷烧制于元代至明代早期,在释光有限的误差范围内符合传统鉴定方法得出的该遗址属于元代这一结论。这有助于揭示该历史时期相关器物的制作工艺、实际用途和可能的产地。此外,这也为理解该历史时期青花瓷器在...  相似文献   
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