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本文研究适用于ＩＣＦ实验的ＣＴ技术，并已用于“星光Ⅱ”装置的激光等离子体的实验Ｘ光测量，重建出Ｘ光的三维分布，获得了有意义的结果，表明该技术在ＩＣＦ实验中的应用的可能性。 相似文献
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This study integrates newly acquired stratigraphic data, geologic mapping, and paleocurrent data to constrain the stratigraphic evolution of the oldest channel-lobe complex in the Upper Cretaceous Cerro Toro Formation in the Silla Syncline area of the Magallanes Basin, termed the Pehoe member. The Pehoe member ranges in thickness from 60 m in the north to at least 410 m farther down system and comprises three separate divisions (A, B, and C). A lower conglomerate unit and an upper one, termed Pehoe A and C divisions respectively, represent the fill of major incised submarine channels or channel complexes. These are separated by stratified sandstone of the Pehoe B division, representing a weakly confined lobe complex, either transient or terminal.The integration of new data with observations from previous studies reveal that the three main coarse-grained conglomerate and sandstone members in the Cerro Toro Formation in the Silla Syncline include at least seven distinct submarine channels or channel complexes and two major lobe complexes. The thinning and disappearance of these units along the eastern limb of the syncline reflect confinement of the flows to a narrow trough or mini-basin bounded to the east by a topographic high. This confinement resulted in unidirectional paleocurrents to the south and southeast in all deposits. Changes in depositional geometries are interpreted as reflecting changes in sediment supply and relative confinement. Submarine channels were from 700 m to 3.5 km wide and occupied a fairway that was 4-5 km wide. Flows moving south and southeast in this mini-basin probably crossed the eastern topographic high south of the present exposures and joined those moving southward along the axis of the foreland basin at least 16 km to the east. 相似文献
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This work evaluates the effects of caging, a known confinement stress, in Nile tilapia (Oreochromis niloticus) during an environmental study in Cubatão river, southern Brazil. Caging animals for 7 days, regardless of being at the reference or at a contaminated site, resulted in lower levels of antioxidant-related defenses (glutathione, glutathione S-transferase, glucose-6-phosphate dehydrogenase) in liver and physiological parameters (blood glucose and lactate) as compared with free-swimming animals. Higher hepatic glutathione reductase activity and elevated Hb content could be associated to contaminant exposure. In conclusion, the confinement stress in caged Nile tilapia biochemical and physiological disturbances, acting as a confounding factor in field studies. 相似文献
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Aggradational lobe fringes: The influence of subtle intrabasinal seabed topography on sediment gravity flow processes and lobe stacking patterns 
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下载免费PDF全文 Yvonne T. Spychala David M. Hodgson Christopher J. Stevenson Stephen S. Flint 《Sedimentology》2017,64(2):582-608
Seabed topography is ubiquitous across basin‐floor environments, and influences sediment gravity flows and sediment dispersal patterns. The impact of steep (several degrees) confining slopes on sedimentary facies and depositional architecture has been widely documented. However, the influence of gentle (fraction of a degree) confining slopes is less well‐documented, largely due to outcrop limitations. Here, exceptional outcrop and research borehole data from Unit A of the Permian Laingsburg Formation, South Africa, provide the means to examine the influence of subtle lateral confinement on flow behaviour and lobe stacking patterns. The dataset describes the detailed architecture of subunits A.1 to A.6, a succession of stacked lobe complexes, over a palinspastically restored 22 km across‐strike transect. Facies distributions, stacking patterns, thickness and palaeoflow trends indicate the presence of a south‐east facing low angle (fraction of a degree) lateral intrabasinal slope. Interaction between stratified turbidity currents with a thin basal sand‐prone part and a thick mud‐prone part and the confining slope results in facies transition from thick‐bedded sandstones to thin‐bedded heterolithic lobe fringe‐type deposits. Slope angle dictates the distance over which the facies transition occurs (hundreds of metres to kilometres). These deposits are stacked vertically over tens of metres in successive lobe complexes to form an aggradational succession of lobe fringes. Extensive slides and debrites are present at the base of lobe complexes, and are associated with steeper restored slope gradients. The persistent facies transition across multiple lobe complexes, and the mass flow deposits, suggests that the intrabasinal slope was dynamic and was never healed by deposition during Unit A times. This study demonstrates the significant influence that even subtle basin‐floor topography has on flow behaviour and depositional architecture of submarine lobe complexes. In addition, we present a new aggradational lobe fringe facies associations and recognition criteria for subtle confinement in less well‐exposed and subsurface basin fills. 相似文献
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Seismic upgrading of old masonry buildings by seismic isolation and CFRP laminates: a shaking-table study of reduced scale models 总被引：2，自引：2，他引：0
The efficiency of improving the seismic resistance of old masonry buildings by means of seismic isolation and confining the
structure with CFRP laminate strips has been investigated. Five models of a simple two-story brick masonry building with wooden
floors without wall ties have been tested on the shaking table. The control model has been built directly on the foundation
slab. The second model has been separated from it by a damp-proof course in the form of a PVC sheet placed in the bed-joint
between the second and the third course, whereas the third model has been isolated by rubber isolators placed between the
foundation slab and structural walls. Models four and five have been confined with CFRP laminate strips, simulating the wall
ties placed horizontally and vertically at floor levels and corners of the building, respectively. One of the CFRP strengthened
models has been placed on seismic isolators. Tests have shown that a simple PVC sheet damp-proof course cannot be considered
as seismic isolator unless adequately designed. Tests have also shown that the isolators alone did not prevent the separation
of the walls. However, both models confined with CFRP strips exhibited significantly improved seismic behavior. The models
did not collapse even when subjected to significantly stronger shaking table motion than that resisted by the control model
without wall ties. 相似文献
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Improved estimators of the transfer function (H2, H3, H4), in addition to the conventional estimator (H1), were used to evaluate the dynamic soil properties and to study the effect of confinement duration on damping and shear modulus of soils. In this study, two types of cohesive soils, a kaolinite and a bentonite, were tested using a resonant column apparatus under random torsional excitation conditions. Root meam square strain levels in the range of 10−3–10−2 and confining pressures in the range of 34.47–150 kPa were considered. The confinement duration ranged from 500 to 20 000 min. The results of this study indicate that as time increases, the difference in damping values obtained by the various estimators of the transfer function decreases, whereas the shear moduli are not influenced by the variation in confinement duration. 相似文献
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