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Upper Barremian – Lower Aptian inner platform “Urgonian” limestones in the Mont de Vaucluse region, SE France, consist of alternating metre-scale microporous and tight intervals. This paper focuses on the influence of structural deformation on the reservoir properties of the Urgonian limestone succession in a study area near the town of Rustrel. Petrographic, petrophysical and structural data were recovered from five fully-cored boreholes, from the walls of a 100 m long underground tunnel, and from a 50 m long transect at a nearby outcrop. The data allowed reservoir property variations in the Urgonian limestones to be studied from core to reservoir scale. Eleven Reservoir Rock Types (RRTs) were identified based on petrographic features (texture, grain size), reservoir properties (porosity, permeability), and the frequency of structural discontinuities such as fractures, faults and stylolites. Tight and microporous reservoir rock types were distinguished. Tight reservoir rock types were characterised by early cementation of intergranular pore spaces and by the presence of frequent structural discontinuities. By contrast microporous reservoir rock types contained preserved intragranular microporosity and matrix permeability, but had very few structural discontinuities. Observed vertical alternations of microporous and tight rock types are interpreted to have been controlled by the early diagenesis of the Urgonian carbonates. Deformation associated with regional-scale tectonic phases, including Albian – Cenomanian “Durancian” uplift (∼105 to 96 Ma) and Pyrenean compression (∼55 to 25 Ma), resulted in the modification of the initial petrophysical properties of the Urgonian limestones. An early diagenetic imprint conditioned both the intensity of structural deformations and the associated circulations of diagenetic and meteoric fluids. Evolution of the Reservoir Rock Types is therefore linked both to the depositional conditions and to subsequent phases of structural deformation.  相似文献   
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The term atmospheric residue describes the material at the bottom of the atmospheric distillation tower having a lower boiling point limit of about 340°C; the term vacuum residue (heavy petroleum fractions) refers to the bottom of the vacuum distillation, which has an atmospheric equivalent boiling point (AEBP) above 540°C. In this work, the objective is to evaluate the behavior of different kinds of Brazilian atmospheric and vacuum residues using molecular distillation. The Falling Film Molecular Distillator was used. For the results obtained through this process, a significant range of temperature can be explored avoiding the thermal decomposition of the material. So these results are very important to the refinery decisions and improvements. The Experimental Factorial Design results showed that the temperature has more influence on the process than the feed flow rate, when a higher percentage of distillate is required.  相似文献   
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The three-dimensional morphology of polyethylene single crystals grown from dilute solution has been examined by atomic force microscopy. Single crystals were deposited on a soft ground of aqueous solution of poly(vinyl alcohol) (PVA) to avoid the collapse of thin lamellar crystals with thickness of 10 nm. The observation of single crystals on dried PVA clarifies the morphology of a chair type crystal as well as well-known hollow pyramidal type. It has been confirmed that the screw dislocations in the chair type follow a selection rule of the handedness in a manner to relieve the distortion in the chair type.  相似文献   
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The gamma aminobutyric acid-A (GABAA) agonist, muscimol, the glutamate N-methyl-D-aspartate (NMDA) receptor antagonist, D-2-amino-5-phosphonopentanoic acid (AP5), and the inhibitor of the extracellularly regulated kinases (ERKs), UO 126, cause retrograde amnesia when administered to the hippocampus. In the present study, the authors found that they all cause retrograde amnesia for 1-trial inhibitory avoidance, not only when infused into the dorsal CA1 region of the hippocampus, but also when infused into the basolateral amygdala or the entorhinal, parietal, and posterior cingulate cortices. The posttraining time course of the effect of each drug was, however, quite different across brain structures. Thus, in all of them, NMDA receptors and the ERK pathway are indispensable for memory consolidation, and GABAA receptor activation inhibits memory consolidation: but in each case, their influence is interwoven differently. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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A quasi-analytical method for computing the quasi-static-TEM parameters of the generalized coplanar waveguide (GCPW) is reported. The structure is assumed to be enclosed in a rectangular frame and embedded in a layered medium. Essentially, the method is an analytically enhanced spectral domain formulation. Its application leads to virtually exact results in very short CPU times, making it suitable for CAD purposes. Although the method is somewhat more time consuming than conformal mapping approaches, it is a useful alternative because of its exactness and ability to deal with multilayer structures. © 1994 John Wiley & Sons, Inc.  相似文献   
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Recent research has proposed the use of asphalt and tall-oil-pitch emulsions for stabilizing radioactive contamination deposited on surfaces in urban areas. The objective of this project was to investigate whether surface applied emulsions could capture airborne radioactive particulate. Laboratory experiments included wind-blown particulate capture studies using an acrylic column and particulate retainment experiments using a wind box capable of producing wind speeds of 96?km/h. A probe methodology was developed to relate particulate retainment to a tack force on the emulsion surface. Experiments were also performed to determine the potential for such emulsions to absorb particulate matter into their emulsion matrix. Tall-oil-pitch emulsions outperformed asphalt emulsions in terms of particulate retention, tack force, and the ability to absorb magnesium silicate. Both tall-oil-pitch and asphalt emulsions were capable of extracting 22–24?g?m?2 of powder from particulate-laden airflow. Tall-oil-pitch emulsions were capable of retaining as much as 5–10% of magnesium silicate powder applied (i.e., retainment densities of 10–20?g?m?2) even after seven?days of curing and after applying 96.5?km/h (60?mph) wind. Tall-oil-pitch emulsions were able to absorb surface-applied magnesium silicate (approximately 0.1–0.2?g of magnesium silicate per 1.0?g of emulsion within three?days) into their emulsion matrix, preventing the magnesium silicate from being exposed to the external environment. Initial results with these five different emulsion formulations suggested particulate capture was feasible. Future emulsion formulations (i.e., longer curing times with greater acid concentrations) should be tested to optimize this postdetonation response strategy.  相似文献   
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There is no better place to test life-saving resuscitation interventions than in the prehospital setting. Patients rarely survive cardiac arrest if resuscitation techniques have failed before leaving the scene. Also, paramedics are usually very experienced in key initial resuscitative techniques, and they routinely operate under strict paramilitary protocol, resulting in better study compliance. In addition, the large study populations that are derived from emergency medical services (EMS) systems lead to faster study completion and statistically stronger data. Most important, by reinforcing standardized care, rigidly scrutinized trials improve patient care, regardless of the effect of the study intervention. The success of productive EMS research centers requires routine communication between hospital and EMS administrators and their medical directors, designation of mutually acceptable data collectors who guarantee confidentiality, reciprocal exchange of study data provided as educational seminars to the hospitals, commitments to support the budget requests of an EMS program and appropriate system modifications, inclusion of EMS personnel in study design from the very beginning, prospective education of the medical community and media before protocol implementation, an authoritative grassroots medical director, and a paramedic supervisor system.  相似文献   
10.
Gut involvement in bladder tumours is low, even exceptional in the presence of surface, low-grade neoplasia. The authors explain their experience in the diagnosis and management of a patient treated endoscopically for a vesical surface tumour which subsequently exhibited peritoneal and gut metastatic seeding. The various mechanisms for gut dissemination of vesical neoplasias and the repercussion of their endoscopic management are discussed.  相似文献   
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