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Articles de revues sur le sujet "MRP FLUID"

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Paswan, Sunil K., et Anant K. Singh. « Analysis of finishing performance in rotating magnetorheological honing process with the effect of particles motion ». Proceedings of the Institution of Mechanical Engineers, Part E : Journal of Process Mechanical Engineering 235, no 4 (26 janvier 2021) : 1104–18. http://dx.doi.org/10.1177/0954408921990132.

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The particles used in magnetorheological polishing (MRP) fluid are the key components of the magnetorheological (MR) finishing processes. The rotational magnetorheological honing (R-MRH) process is recently developed as a highly productive MR finishing process which is used for finishing the internal surface of the industrial cylindric components. The involvement of micron-sized abrasive particles of MRP fluid in the finishing operation results in the invisible observation of the finishing mechanism which enables the urge of analyzing the motion of the particles during the present R-MRH process. Therefore, the effect of motions of the MRP-fluid’s particles is analyzed for nano-finishing performance on the inside surface of the cylindric workpieces. The motions performed by active abrasive particles on the inside surface of the rotating hollow cylindric workpiece cause a higher finishing rate. The effects of particle motions on the reduction in surface roughness and improvement in surface morphology confirm the usefulness of the R-MRH process. The surface finish with the effect of the particles' motions of the MRP-fluid in the R-MRH process on the stationary workpiece’s inner surface is achieved upto 100 nm from 420 nm of the initial ground surface in 60 min of finishing. Whereas, the same aforementioned surface of the rotating workpiece is finished upto 50 nm from the same initial ground surface in only 40 min of finishing with the effect of the particles' motions of the MRP-fluid. The improvement in the surface finish is also noticed through the scanning electron micrographs in this work. The significant change in surface finish obtained in experimentations confirms the integrity of the analytical study conducted for understanding the effects of motions of particles while finishing with the R-MRH process.
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Smits, Katrien, Yannick Gansemans, Laurentijn Tilleman, Filip Van Nieuwerburgh, Margot Van De Velde, Ilse Gerits, Cyrillus Ververs et al. « Maternal Recognition of Pregnancy in the Horse : Are MicroRNAs the Secret Messengers ? » International Journal of Molecular Sciences 21, no 2 (9 janvier 2020) : 419. http://dx.doi.org/10.3390/ijms21020419.

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The signal for maternal recognition of pregnancy (MRP) has still not been identified in the horse. High-throughput molecular biology at the embryo–maternal interface has substantially contributed to the knowledge on pathways affected during MRP, but an integrated study in which proteomics, transcriptomics and miRNA expression can be linked directly is currently lacking. The aim of this study was to provide such analysis. Endometrial biopsies, uterine fluid, embryonic tissues, and yolk sac fluid were collected 13 days after ovulation during pregnant and control cycles from the same mares. Micro-RNA-Sequencing was performed on all collected samples, mRNA-Sequencing on the same tissue samples and mass spectrometry was conducted previously on the same fluid samples. Differential expression of miRNA, mRNA and proteins showed high conformity with literature and confirmed involvement in pregnancy establishment, embryo quality, steroid synthesis and prostaglandin regulation, but the link between differential miRNAs and their targets was limited and did not indicate the identity of an unequivocal signal for MRP in the horse. Differential expression at the embryo–maternal interface was prominent, highlighting a potential role of miRNAs in embryo–maternal communication during early pregnancy in the horse. These data provide a strong basis for future targeted studies.
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Jayant et V. K. Jain. « Analysis of finishing forces and surface finish during magnetorheological abrasive flow finishing of asymmetric workpieces ». Journal of Micromanufacturing 2, no 2 (9 avril 2019) : 133–51. http://dx.doi.org/10.1177/2516598418818260.

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Magnetorheological abrasive flow finishing (MRAFF) is an advanced hybrid process for producing ultrafine finished surfaces. Such surfaces reduce frictional forces and thereby minimize wear and tear to increase functional lifetime of the components. In the present research work, a model has been developed for simulating the results of MRAFF process. First, magnetic field is simulated and then a detailed study on the rheology of the magnetorheological polishing (MRP) fluid is conducted to develop a viscosity model for the flow of non-Newtonian shear thinning fluid. To calculate the forces acting in the process of material removal, the flow of MRP fluid around an asymmetric workpiece (knee joint) in a spatially varying magnetic field is simulated. Finishing forces exerted by the abrasive particles on the workpiece surface are analysed to develop a model for predicting surface roughness. A methodology has been proposed to evolve a variable correction factor to determine active abrasive particles at different locations on the workpiece surface for accurate simulation of surface finish operation. It is found that the magnetic field greatly influences the process performance by governing the viscosity of the MRP fluid and the distribution of the abrasive particles in the medium. During finishing of an asymmetric workpiece, the surface finish obtained at different locations on the workpiece surface is different. The developed model is capable to predict final surface finish within the acceptable accuracy when compared with the experimental results.
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KORDONSKI, W. I., et S. D. JACOBS. « MAGNETORHEOLOGICAL FINISHING ». International Journal of Modern Physics B 10, no 23n24 (30 octobre 1996) : 2837–48. http://dx.doi.org/10.1142/s0217979296001288.

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The technology of finishing for optics, ceramics, and semiconductors is one of the most promising uses of the magnetorheological effect. It perfectly coupled with computer control, allowing in quantity production the unique accuracy and quality of a polished surface to be achieved. The polishing process may appear as follows. A part rotating on the spindle is brought into contact with an magnetorheological polishing (MRP) fluid which is set in motion by the moving wall. In the region where the part and the MRP fluid are brought into contact, the applied magnetic field creates the conditions necessary for the material removal from the part surface. The material removal takes place in a certain region contacting the surface of the part which can be called the polishing spot or zone. The polishing process comes to the program-simulated movement of the polishing spot over the part surface. The mechanism of the material removal in the contact zone is considered as a process governed by the particularities of the Bingham flow in the contact zone. The problem like the hydrodynamic theory of lubrication is treated for plastic film. As this takes place the shear stresses distribution in the film is obtained from the experimental measurements of the pressure distribution in the contact spot. Reasonable correlation between calculated and experimental magnitudes of the material removal rate for glass polishing lends support to the validity of the approach.
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Michot, Jean-Michel, Marie F. Heremans, Nancy E. Caceres, Marie-Paule Mingeot-Leclercq, Paul M. Tulkens et Françoise Van Bambeke. « Cellular Accumulation and Activity of Quinolones in Ciprofloxacin-Resistant J774 Macrophages ». Antimicrobial Agents and Chemotherapy 50, no 5 (mai 2006) : 1689–95. http://dx.doi.org/10.1128/aac.50.5.1689-1695.2006.

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ABSTRACT Ciprofloxacin is the substrate for a multidrug resistance-related protein (MRP)-like multidrug transporter in J774 mouse macrophages, which also modestly affects levofloxacin but only marginally affects garenoxacin and moxifloxacin (J.-M. Michot et al., Antimicrob. Agents Chemother. 49:2429-2437, 2005). Two clones of ciprofloxacin-resistant cells were obtained by a stepwise increase in drug concentration (from 34 to 51 to 68 mg/liter) in the culture fluid. Compared to wild-type cells, ciprofloxacin-resistant cells showed (i) a markedly reduced ciprofloxacin accumulation (12% of control) and (ii) a two- to threefold lower sensitivity to the enhancing effect exerted by MRP-inhibitors (probenecid and MK571) on ciprofloxacin accumulation or by ciprofloxacin itself. ATP-depletion brought ciprofloxacin accumulation to similarly high levels in both wild-type and ciprofloxacin-resistant cells. Garenoxacin and moxifloxacin accumulation remained unaffected, and levofloxacin showed an intermediate behavior. DNA and protein synthesis were not impaired in ciprofloxacin-resistant cells for ciprofloxacin concentrations up to 100 mg/liter (∼85 and 55% inhibition, respectively, in wild-type cells). In Listeria monocytogenes-infected ciprofloxacin-resistant cells, 12-fold higher extracellular concentrations of ciprofloxacin were needed to show a bacteriostatic effect in comparison with wild-type cells. The data suggest that the resistance mechanism is mediated by an overexpression and/or increased activity of the MRP-like ciprofloxacin transporter expressed at a basal level in wild-type J774 macrophages, which modulates both the intracellular pharmacokinetics and activity of ciprofloxacin.
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Zheng, Cheng, Bingsan Chen, Xiaoyu Yan, Yongchao Xu et Shangchao Hung. « The three-point eccentric magnetorheological polishing technology for hard brittle alumina ceramics ». Mechanical Sciences 13, no 1 (20 mai 2022) : 473–83. http://dx.doi.org/10.5194/ms-13-473-2022.

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Abstract. This work presents the design of a pressurised three-point eccentric magnetorheological polishing (MRP) device, for alumina ceramics' hard and brittle characteristics, and a carrier disc magnetic field generator and a single closed-loop uniform magnetic field generator for a more uniform and increased magnetic field distribution. When compared with the traditional gap type, this device considerably enhances polishing efficiency. This apparatus has also been used to explore the mechanism of MRP. Static magnetic field simulations were conducted, and the fundamentals of the three-point eccentric magnetorheological process were addressed. Alumina ceramics were polished with a three-point eccentric wheel MRP equipment. Polishing tests were conducted to explore the effects of rotational speed, working pressure, abrasive type, abrasive particle size and polishing duration on polishing properties, and optimised polishing parameters were established. The surface roughness (Ra) of the samples was dramatically reduced from 500 to 22.41 nm using the three-point eccentric MRP device. The pit markings on the alumina ceramics' surface vanished after polishing. Therefore, the approach has considerable polishing potential for hard and brittle materials that can be nanofabricated with minimal surface sub-damage.
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Lundy, Fionnuala T., Rod Chalk, Philip-John Lamey, Christopher Shaw et Gerard J. Linden. « Quantitative analysis of MRP-8 in gingival crevicular fluid in periodontal health and disease using microbore HPLC ». Journal of Clinical Periodontology 28, no 12 (7 juillet 2008) : 1172–77. http://dx.doi.org/10.1111/j.1600-051x.2001.281213.x.

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Lundy, Fionnuala T., Rod Chalk, Philip-John Lamey, Christopher Shaw et Gerard J. Linden. « Quantitative analysis of MRP-8 in gingival crevicular fluid in periodontal health and disease using microbore HPLC ». Journal of Clinical Periodontology 28, no 12 (décembre 2001) : 1172–77. http://dx.doi.org/10.1034/j.1600-051x.2001.281213.x.

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Achouiti, Ahmed, Thomas Vogl, Anne J. Van der Meer, Ingrid Stroo, Sandrine Florquin, Onno J. de Boer, Johannes Roth et al. « Myeloid-related protein-14 deficiency promotes inflammation in staphylococcal pneumonia ». European Respiratory Journal 46, no 2 (18 mars 2015) : 464–73. http://dx.doi.org/10.1183/09031936.00183814.

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Staphylococcus aureus has evolved as an important cause of pneumonia in both hospital and community settings. Staphylococcal lung infection can lead to overwhelming pulmonary inflammation. During infection, neutrophils release complexes of myeloid-related protein (MRP)8 and MRP14 (MRP8/14). MRP8/14 has been shown to exert pro-inflammatory and chemotactic activity, and to assist in the killing of S. aureus. In the current study we sought to determine the role of MRP8/14 in the host response during S. aureus pneumonia.Pneumonia was induced in wildtype and MRP14-deficient mice (mice unable to form MRP8/14) by intranasal inoculation of 1×107 CFU of S. aureus USA300. Mice were sacrificed at 6, 24, 48 or 72 h after infection for analyses.S. aureus pneumonia was associated with a strong rise in MRP8/14 in bronchoalveolar lavage fluid and lung tissue. Surprisingly, MRP14 deficiency had a limited effect on bacterial clearance and was associated with increased cytokine levels in bronchoalveolar lavage fluid and aggravated lung histopathology. MRP14 deficiency in addition was associated with a diminished transmigration of neutrophils into bronchoalveolar lavage fluid at late time-points after infection together with reduced release of nucleosomes.MRP8/14 serves in an unexpected protective role for the lung in staphylococcal pneumonia.
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Kukreja, Rishabh, Pratyush Tanwar, Vatsal Verma et Niranjan M S. « Design and Analysis of a Polishing Tool for Different MRP Fluid in the Magnetic Field Assisted Finishing (MFAF) Process ». International Journal of Engineering Trends and Technology 68, no 5 (25 mai 2020) : 54–61. http://dx.doi.org/10.14445/22315381/ijett-v68i5p210s.

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Thèses sur le sujet "MRP FLUID"

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Lefèvre, Xavier. « Grafting of ‘push-pull’ systems on germanium : towards the electric passivation ». Palaiseau, Ecole polytechnique, 2012. https://theses.hal.science/tel-00782709.

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Les excellentes propriétés électroniques du germanium limitées par la faible qualité isolante de son oxyde rendent le développement de nouveaux matériaux diélectriques nécessaires. En outre, la sensibilité du germanium requiert la création d'une couche passivante de surface pour le protéger. Bien que de nombreuses études soient réalisées pour le développement de nouveaux diélectriques inorganiques, ce projet de recherche en rupture concerne la conception, la réalisation et le développement de film mince diélectrique organique passivant sur le germanium pour des applications en nanoélectronique. Le travail réalisé porte principalement sur la synthèse de nouvelles molécules " push-pull " (systèmes conjugués linéaires portant de part et d'autres un groupe donneur et un groupe accepteur) et sur la fonctionnalisation du germanium. Plusieurs nouveaux systèmes donneur-accepteur ainsi que des systèmes conjugués linéaires contenant une fonction d'ancrage ont été synthétisés selon de nouvelles voies. En particulier, une série de dérivés azobenzène contenant différents accepteurs (groupes fluorés, pyridinium, nitro) et donneurs (amines, alcoxyl) ainsi que des fonctions d'ancrage variées (thiol, acide carboxylique, sel de diazonium, triazene) a été obtenue. En parallèle, la préparation et la fonctionnalisation de surfaces de germanium ont été étudiées. Un nouveau procédé permettant d'enlever l'oxyde natif de la surface et d'obtenir des surfaces halogénées de faible rugosité a été développé. Les substrats de germanium ont été fonctionnalisés par des thiols mais également par des sels de diazonium. Ce nouveau processus de greffage spontané a permis d'abaisser considérablement le temps de réaction (15 minutes de greffage spontané des sels de diazonium contre 3 jours pour la formation de monocouches auto-assemblées de thiols) tout en travaillant dans des conditions douces. Les films minces ainsi obtenus présentent une stabilité comparable à celles des monocouches de thiols. Des systèmes conjugués linéaires ont été greffés à la fois sous forme de thiol et sous forme de sels de diazonium afin de déterminer l'influence du noyau aromatique sur la formation du film et sur ses propriétés. Enfin, les systèmes " push-pull " ont également été greffés. Des premières études électroniques sur or avec les systèmes conjugués linéaires ont été réalisées. Ces études ont été étendues au germanium et laissent envisager des résultats significatifs avec les molécules " push-pull "
Despite its excellent electronic properties, germanium is limited by the low passivation of its oxide. Therefore, new dielectrics must be developed. Furthermore, germanium sensitivity requires the creation of a passivation layer on the surface. Even if numerous studies were carried out on new inorganic dielectrics, this research project concerns the design, the realization and the development of thin passivating organic dielectric films on germanium for nanoelectronics applications. This work principally involves the synthesis of new push-pull molecules (π-conjugated systems bearing a donor and an acceptor part) and germanium functionalization. New donor-acceptor systems and π-conjugated linear systems containing an anchoring group were synthesized through new ways. In particular, a series of azobenzene derivatives with different acceptors (fluorinated groups, pyridinium, nitro) and donors (amines, alkoxyl) and various anchoring groups (thiol, carboxylic acid, diazonium salt, triazene) was obtained. Meanwhile, preparation and functionalization of germanium surfaces was studied. A new process to etch the native oxide and obtain halogenated surfaces with low roughness was developed. Germanium substrates were then functionalized with thiol but also with diazonium salts. This new spontaneous grafting process considerably decreased the reaction time (15 minutes spontaneous grafting of diazonium salts against 3 days for self-assembled monolayers of thiol formation) in mild conditions. Thin films obtained present stability similar to the one of thiol monolayers. Π-conjugated linear systems were grafted both as thiol and diazonium salt to probe the influence of the aromatic core on the film formation and properties. Finally, push-pull systems were also grafted. Electronic studies on gold with π-conjugated systems were realized. These studies were extended to germanium and allow expecting significant results with push-pull molecules
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Bergman, Robert Loring. « Matrix Metalloproteinases 2 and 9 in Normal Canine Cerebrospinal Fluid ». Thesis, Virginia Tech, 2001. http://hdl.handle.net/10919/33750.

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Cerebrospinal fluid (CSF) analysis is a standard part of a diagnostic evaluation. Commonly evaluated components include the cell count, protein concentration, glucose, and cytology. CSF analysis can be diagnostic in some diseases such as fungal infections and CNS lymphoma. Often, CSF analysis is not specific, but more information can be obtained. Matrix Metalloproteinases (MMPs) are enzymes that have been found in human CSF. They are calcium and zinc dependent endoproteinases with overlapping substrates. They hydrolyze at least one component of tissue extracellular matrix (ECM), such as collagen or elastin. They are important in normal physiologic processes such as angiogenesis, reproduction and wound healing. One class of MMPs, the gelatinases, degrade gelatins and type IV collagen include MMP 2 and MMP 9. MMPs are important in many pathological processes that involve unregulated matrix destruction such as arthritis, neoplasia and CNS diseases. MMP2 is known to be constituitively produced in CSF while MMP 9 is present only in certain pathologic conditions such as multiple sclerosis, neoplasia and inflammatory diseases. We hypothesize that MMP2 is present in normal canine CSF while MMP 9 is absent. Cerebrospinal fluid samples were taken from 23 normal dogs that were being used for other research purposes. Each CSF sample was evaluated immediately for red blood cells (RBCs), white blood cells (WBCs), protein, and glucose, and then stored at -70°C. Cytological examination was also performed. CSF samples were considered normal if the protein was less than 25 mg/dl, WBCs were less than 6 µl, and RBCs were less than 25 µl. Each dog was euthanized and the brains processed for routine histopathology. MMP analysis was done using gelatin zymography and an enzyme linked immunosorbent assay (ELISA). Bands of enzyme activity were visible following staining due to enzyme degradation of the gelatin. A commercially available polyclonal sandwich ELISA was used to identify the pro form of MMP2. The mean WBC count for the CSF samples was 0.96 WBC/ml with a range of 0-3 WBC/ml. The mean protein was 12 mg/dl, with a range of 8-17 mg/dl. The mean RBC count was 3.65 RBC/ml with a range of 0-21 RBC/ml. All normal samples of CSF contained a band of clearing that corresponded to the human commercial standard of proMMP2. No other major bands of clearing were noted on normal samples. The commercial human standards also contained ProMMP2. Other bands were present, but were faint and variable. Using a polyclonal antibody based sandwich ELISA, with samples run in triplicate, the mean pro MMP 2 levels were determined to be 5.61 ng/ml with a range of 3.36 - 10.83 ng/ml. We conclude that normal CSF values are narrower than what has been previously reported for protein concentration and WBC count. Also, the pro form of MMP 2 is present in normal canine CSF based on results of gelatin zymography and ELISA.
Master of Science
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Al-Mugheiry, Mohammed Adil Said. « MRI studies of fluids permeating porous media ». Thesis, University of Nottingham, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.321376.

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Valkov, Boris Ivanov. « A blurred interface formulation of The Reference Map Technique for Fluid-Solid Interactions and Fluid-Solid-Solid Interactions ». Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/92123.

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Thesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2014.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 143-144).
In this work we present a blurred interface method for Fluid-Solid Interactions (FSI) and multiple solids immersed in a fluid or FSSI (Fluid-Solid-Solid Interactions) based on the reference map technique as presented by Kamrin and Rycroft. I will follow the chain of thought which lead from the initial sharp interface technique to the newer blurred interface one. We will present its capabilities of doing fully-coupled simulations of a compressible Navier-Stokes fluid and highly non-linear solid undergoing large deformations all performed on a single Eulerian grid with no Lagrangian particles whatsoever. The Reference Map Technique (RMT) provides an Eulerian simulation framework allowing to compute fully coupled fluid/soft-solid interactions. However, due to the extrapolations inherent to the Ghost Fluid Method (GFM) for fluid/fluid interactions, on which the RMT is based, numerical artifacts get created in the resulting pressure and velocity fields whenever the levelset defining the interface crosses a gridpoint from the fixed cartesian grid utilized in this method. We will therefore follow the creation and propagation of these artifacts as well as analyze how the blurred technique solves or avoids these problems.
by Boris Ivanov Valkov.
S.M.
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Aydar, Gokhan. « A new magneto-rheological fluid (MRF) washing machine damper and a novel two-way-controllable MRF valve ». abstract and full text PDF (free order & ; download UNR users only), 2006. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1441431.

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Davies, Colin John Stephen. « MRI studies of complex fluids and microchannel flows ». Thesis, University of Cambridge, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.598355.

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This thesis considers the use of NMR (Nuclear Magnetic Resonance) in investigating both the formulation, using microchannels, and characterisation of complex fluids using NMR techniques. Multiphase microchannel flows have many applications and understanding the hydrodynamics and mass transfer is essential for developing such systems. Time-averaged velocity images of the parallel flow of PDMS (polydimethylsiloxane) and water in a 500 μm x 250 μm microchannel were compared with an analytical solution and simulations. This was extended into imaging multiphase flows in a smaller (250 μm x 100 μm) microchannel. Poor signal-to-noise levels in this geometry led to the adoption of a spatially- and chemical-shift-resolved propagator acquisition. This was used to differentiate two different flow regimes: parallel flow and droplet production. RheoNMR is the use of NMR techniques in the study of rheology. Time-averaged velocity imaging was used to image a shear-banding micellar solution, cetylpyridinum chloride with sodium salicylate (CPyC1 / NaSal) in sodium chloride brine, in a variety of standard rheological geometries. The fast velocity measurement sequence GERVAIS was used to measure starting and stopping of flows of the CPyC1 / NaSal solution in a wide-gap Couette cell; these were compared to similar experiments performed using PDMS. The propagation of an elastic wave across the cell was seen during start-up and an unusual rebounding oscillation was evident in the stopped flow experiments in the CPyC1 sample. The fast diffusion measurement sequence, Difftrain, was modified to reduce the achievable incremental observation time (at the expense of slightly reduced chemical resolution). This was applied to two case studies: measuring the surface-to-volume ratio of a model porous medium and the droplet sizing of oil-in-water emulsions manufactured with fast-diffusing oils. Finally, NMR relaxometry and diffusometry were used to investigate a phase transition in the structure of a sample of a commercial face cream.
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Balasubramanian, Ganapathi Raman. « Low-order coupled map lattices for estimation of wake patterns behind vibrating flexible cables ». Link to electronic thesis, 2003. http://www.wpi.edu/Pubs/ETD/Available/etd-0908103-105504.

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Thesis (Ph. D.)--Worcester Polytechnic Institute.
Keywords: fluid-structure interaction; low dimensional models; coupled map lattices; vortex shedding; cylinder wake patterns; flow control; multi-variable least squares algorithm; neural networks; adaptive estimation. Includes bibliographical references (p. 147-149).
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Johnson, Kevin Robert. « In Vivo Coronary Wall Shear Stress Determination Using CT, MRI, and Computational Fluid Dynamics ». Diss., Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/14482.

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Wall shear stress (WSS) has long been identified as a factor in the development of atherosclerotic lesions. Autopsy studies have revealed a strong tendency for lesion development at arterial branch sites and along the inner walls of curvature areas that, in theory, should experience low WSS. Calculations of coronary artery WSS have typically been based upon average models of coronary artery geometry with average flow conditions and then compared to average lesion distributions. With all the averaging involved, a more detailed knowledge of the correlation between WSS and atherosclerotic lesion development might be obscured. Recent advancements in hemodynamic modeling now enable the calculation of WSS in individual subjects. An image-based approach for patient-specific calculation of in vivo WSS using computational fluid dynamics (CFD) would allow a more direct study of this correlation. New state-of-the-art technologies in multi-detector computed tomography (CT) and 3.0 Tesla magnetic resonance imaging (MRI) offer potential improvements for the measurement of coronary artery geometry and blood flow. The overall objective of this research was to evaluate the quantitative accuracy of multi-detector CT and 3.0 Tesla MRI and incorporate those imaging modalities into a patient-specific CFD model of coronary artery WSS. Using a series of vessel motion phantoms, it has been shown that 64-detector CT can provide accurate measurements of coronary artery geometry for heart rates below 70 beats per minute. A flow phantom was used to validate the use of navigator-echo gated, phase contrast MRI at 3.0 Tesla to measure velocity of coronary blood flow. Patient-specific, time-resolved CFD models of coronary WSS were created for two subjects. Furthermore, it was determined that population-average velocity curves or steady state velocities can predict locations of high or low WSS with high degrees of accuracy compared to the use of patient-specific blood flow velocity measurements as CFD boundary conditions. This work is significant because it constitutes the first technique to non-invasively calculate in vivo coronary artery WSS using image-based, patient-specific modeling.
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Alrwaili, Amgad, et Martin Bencsik. « Quantification of MRI sensitivity for mono-disperse microbubbles to measure subatmospheric fluid pressure changes ». Diffusion fundamentals 18 (2013) 4, S. 1-5, 2013. https://ul.qucosa.de/id/qucosa%3A13710.

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It would be very beneficial to perform MRI of fluids and sense the fluid pressure changes. Our aim is to demonstrate a contrast agent capable of MR sensitivity to sub-atmospheric pressure changes. To achieve this, monodisperse microbubbles were prepared with an optically measured mean radius of 1.4 ± 0.8 μm. A repeated pressure change cycle was applied on the microbubble contrast agent, until it produced an MR signal change solely due to the bubble radius change. The bubbles’ contribution to the relaxation rate before and after applying sub-atmospheric pressure changes was estimated and its echo time dependence modelled, so as to inform the mean radius change. The periodic subatmospheric pressure change was further applied until the MR signal change was only due to the bubble radius change. An excellent MR sensitivity of 28 % bar-1 is demonstrated, bubble radii of 2.4 and 1.8 μm are numerically estimated before and after the application of pressure, and the simulations are further used to estimate the optimum bubble radius maximising the MR sensitivity to a small change in radius.
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Alrwaili, Amgad, et Martin Bencsik. « Quantification of MRI sensitivity for mono-disperse microbubbles to measure subatmospheric fluid pressure changes ». Universitätsbibliothek Leipzig, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-184234.

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It would be very beneficial to perform MRI of fluids and sense the fluid pressure changes. Our aim is to demonstrate a contrast agent capable of MR sensitivity to sub-atmospheric pressure changes. To achieve this, monodisperse microbubbles were prepared with an optically measured mean radius of 1.4 ± 0.8 μm. A repeated pressure change cycle was applied on the microbubble contrast agent, until it produced an MR signal change solely due to the bubble radius change. The bubbles’ contribution to the relaxation rate before and after applying sub-atmospheric pressure changes was estimated and its echo time dependence modelled, so as to inform the mean radius change. The periodic subatmospheric pressure change was further applied until the MR signal change was only due to the bubble radius change. An excellent MR sensitivity of 28 % bar-1 is demonstrated, bubble radii of 2.4 and 1.8 μm are numerically estimated before and after the application of pressure, and the simulations are further used to estimate the optimum bubble radius maximising the MR sensitivity to a small change in radius.
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Livres sur le sujet "MRP FLUID"

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The craniocervical syndrome and MRI. Basel : Karger, 2015.

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Rajeev, S. G. Fluid Mechanics. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198805021.001.0001.

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Starting with a review of vector fields and their integral curves, the book presents the basic equations of the subject: Euler and Navier–Stokes. Some solutions are studied next: ideal flows using conformal transformations, viscous flows such as Couette and Stokes flow around a sphere, shocks in the Burgers equation. Prandtl’s boundary layer theory and the Blasius solution are presented. Rayleigh–Taylor instability is studied in analogy with the inverted pendulum, with a digression on Kapitza’s stabilization. The possibility of transients in a linearly stable system with a non-normal operator is studied using an example by Trefethen et al. The integrable models (KdV, Hasimoto’s vortex soliton) and their hamiltonian formalism are studied. Delving into deeper mathematics, geodesics on Lie groups are studied: first using the Lie algebra and then using Milnor’s approach to the curvature of the Lie group. Arnold’s deep idea that Euler’s equations are the geodesic equations on the diffeomorphism group is then explained and its curvature calculated. The next three chapters are an introduction to numerical methods: spectral methods based on Chebychev functions for ODEs, their application by Orszag to solve the Orr–Sommerfeld equation, finite difference methods for elementary PDEs, the Magnus formula and its application to geometric integrators for ODEs. Two appendices give an introduction to dynamical systems: Arnold’s cat map, homoclinic points, Smale’s horse shoe, Hausdorff dimension of the invariant set, Aref ’s example of chaotic advection. The last appendix introduces renormalization: Ising model on a Cayley tree and Feigenbaum’s theory of period doubling.
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Oikonomopoulou, Katerina, et Vinod Chandran. Biomarkers of psoriatic arthritis outcomes. Oxford University Press, 2018. http://dx.doi.org/10.1093/med/9780198737582.003.0022.

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Psoriatic arthritis is an inflammatory musculoskeletal disease that occurs in patients suffering from psoriasis. The disease manifests with symptoms affecting the skin, peripheral and axial joints, and periarticular structures. Diagnosis and management of psoriatic arthritis is challenging due to its heterogeneous presentation. However, early diagnosis and subsequent appropriate treatment reduces disease activity, prevents joint damage, and improves long-term outcome. It is hoped that biomarkers for disease progression and activity will aid in cost-effective clinical management of patients. Potential biomarkers under investigation for psoriatic arthritis are disease-related components derived from skin and articular tissues, biological fluids, such as blood and synovial fluid, and arthritis-associated cell populations. Imaging including ultrasound and MRI are also being evaluated as biomarkers for diagnosis, activity and outcome. Despite the challenge of bringing these new markers into the clinic, many of these markers hold promise for the future management of patients with psoriatic arthritis.
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Keshav, Satish, et Palak Trivedi. Investigation in liver disease. Sous la direction de Patrick Davey et David Sprigings. Oxford University Press, 2018. http://dx.doi.org/10.1093/med/9780199568741.003.0208.

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This chapter discusses investigations in liver disease, including blood tests (liver chemistry and liver function tests, alpha-fetoprotein, viral serology, antibodies and immunoglobulins), ascetic fluid analysis, imaging (hepatobiliary ultrasound, CT, MRI, endoscopic ultrasound), and liver biopsy.
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Wood Ranch thermal anomaly, Iron County, Utah : self-potential survey and fluid chemistry. Utah Geological Survey, 1991. http://dx.doi.org/10.34191/mp-91-4.

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Klimo, Paul, et Nir Shimony. Ependymomas. Oxford University Press, 2018. http://dx.doi.org/10.1093/med/9780190696696.003.0026.

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Pediatric posterior fossa tumors are usually ependymoma, pilocytic astrocytoma, or medulloblastoma. Ependymoma appears well-demarcated with heterogeneous enhancement on magnetic resonance imaging (MRI). Full neural axis MRI is indicated to assess for metastatic disease. Management is typically surgical resection of the tumor, with consideration for cerebrospinal fluid diversion if patients present with severe hydrocephalus. Extent of resection of the tumor is the most important factor in predicting recurrence and overall survival, and gross total resection is ideal. Infratentorial ependymomas have 2 molecular subtypes, which has implications for responsiveness to adjuvant therapy and prognosis. Infratentorial ependymomas are biologically different from supratentorial ependymomas. Postoperative radiation improves local control.
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Chappell, Michael, Bradley MacIntosh et Thomas Okell. Partial Volume Effects. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780198793816.003.0006.

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Partial volume effects are present in all medical imaging methods, and they play a specific role in arterial spin labeling (ASL) MRI measurements of perfusion. This chapter demonstrates how differences in the perfusion properties of gray matter, white matter, and cerebrospinal fluid give rise to the distinctive visual appearance of cerebral perfusion images. The implications of this for quantification of perfusion in gray matter are discussed and solutions to correct for partial volume effects presented.
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Bates, David. Brainstem syndromes. Oxford University Press, 2012. http://dx.doi.org/10.1093/med/9780199204854.003.02409_update_001.

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Case History—A 78 yr old woman presenting with brainstem signs following a seizure.Brainstem syndromes typically cause ipsilateral cranial nerve lesions and contralateral long tract signs. They are commonly due to brainstem ischaemia, but can also be caused by neoplasia, demyelination, infective and hamartomatous lesions. Imaging, ideally with MRI rather than CT, is obligatory and only then—and possibly following other investigations to identify systemic abnormality or cerebrospinal fluid changes—can appropriate therapy be introduced....
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Flanagan, Eoin P., et Richard J. Caselli. Other Proven and Putative Autoimmune Disorders of the CNS. Oxford University Press, 2017. http://dx.doi.org/10.1093/med/9780199937837.003.0093.

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The historical term “Hashimoto’s encephalopathy” describes a serologically diverse spectrum of autoimmune encephalopathies that tend to be highly steroid responsive and unassociated with cancer. Patients typically present with subacute cognitive decline and serological evidence of autoimmunity that includes but is not limited to thyroid antibodies. An inflammatory spinal fluid and, in a subset of patients, MRI signal abnormalities are supportive. Patients often respond promptly to corticosteroids but relapses are typical. The continued discovery of novel neural-specific-autoantibodies such as voltage-gated-potassium-channel-autoantibodies associated with autoimmune encephalopathies highlights why the term “Hashimoto’s” is misleading. The authors advocate the more general term “autoimmune encephalopathy.”
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Sedel, Frédéric. Krabbe Disease in Adults. Oxford University Press, 2016. http://dx.doi.org/10.1093/med/9780199972135.003.0051.

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Krabbe disease (globoid cell leukodystrophy) is an autosomal recessive lysosomal storage disease caused by mutations in the lysosomal galactocerebrosidase (galactosyl ceramidase) gene. Krabbe disease usually presents as a severe leukodystrophy in early infancy and childhood. In contrast, adult patients usually present with progressive spastic paraparesis. Other signs of the disease include peripheral neuropathy, dysarthria, cerebellar ataxia, pes cavus deep sensory signs, tongue atrophy, optic neuropathy, cognitive decline. Cerebrospinal fluid protein concentration is moderately increased in adults. High signals of cortico-spinal tracts on brain MRI are highly suggestive and this typical aspect may be associated with hyper-intensities of optic radiations, and of the posterior part of the corpus callosum.
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Chapitres de livres sur le sujet "MRP FLUID"

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Webb, Gary. « The Lagrangian Map ». Dans Magnetohydrodynamics and Fluid Dynamics : Action Principles and Conservation Laws, 191–208. Cham : Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-72511-6_10.

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Puente, Gorka, et Oscar Díaz. « Wiki Refactoring as Mind Map Reshaping ». Dans Notes on Numerical Fluid Mechanics and Multidisciplinary Design, 646–61. Cham : Springer International Publishing, 2012. http://dx.doi.org/10.1007/978-3-642-31095-9_42.

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Seitz, Timo, Ansgar Lechtenberg et Peter Gerlinger. « Rocket Combustion Chamber Simulations Using High-Order Methods ». Dans Notes on Numerical Fluid Mechanics and Multidisciplinary Design, 381–94. Cham : Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-53847-7_24.

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Abstract High-order spatial discretizations significantly improve the accuracy of flow simulations. In this work, a multi-dimensional limiting process with low diffusion (MLP$$^\text {ld}$$) and up to fifth order accuracy is employed. The advantage of MLP is that all surrounding volumes of a specific volume may be used to obtain cell interface values. This prevents oscillations at oblique discontinuities and improves convergence. This numerical scheme is utilized to investigate three different rocket combustors, namely a seven injector methane/oxygen combustion chamber, the widely simulated PennState preburner combustor and a single injector chamber called BKC, where pressure oscillations are important.
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Annunziata, P. « Cerebrospinal fluid markers of demyelination : MBP and anti-brain protein antibodies ». Dans Cerebrospinal Fluid Analysis in Multiple Sclerosis, 105–12. Milano : Springer Milan, 1996. http://dx.doi.org/10.1007/978-88-470-2205-8_9.

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Furtado, Ana I., Raquel Viveiros et Teresa Casimiro. « MIP Synthesis and Processing Using Supercritical Fluids ». Dans Molecularly Imprinted Polymers, 19–42. New York, NY : Springer US, 2021. http://dx.doi.org/10.1007/978-1-0716-1629-1_3.

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Runge, Val M., et Johannes T. Heverhagen. « Fluid-Attenuated IR With Fat Saturation (FLAIR FS) ». Dans The Physics of Clinical MR Taught Through Images, 96–97. Cham : Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-85413-3_45.

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Decher, Reiner. « The Vortex—A Journey into Beauty and Mystery ». Dans The Vortex and The Jet, 1–4. Singapore : Springer Singapore, 2022. http://dx.doi.org/10.1007/978-981-16-8028-1_1.

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AbstractVorticity is everywhere. We cannot live without it and we cannot fly without it. The vortex as a construct of fluid motion is necessary for the wing to lift. The propulsion system, be it a propeller or a jet engine, also needs a vorticity to provide the force needed to overcome the resistance of motion through air. This chapter is a road map of how we will proceed on a journey of exploration that will take us from abstract ideas to the observation of beauty and the realization of great flight performance.
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Kaiya, Haruhiko, Masaaki Tanigawa, Shunichi Suzuki, Tomonori Sato et Kenji Kaijiri. « Spectrum Analysis for Quality Requirements by Using a Term-Characteristics Map ». Dans Notes on Numerical Fluid Mechanics and Multidisciplinary Design, 546–60. Cham : Springer International Publishing, 2009. http://dx.doi.org/10.1007/978-3-642-02144-2_42.

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Fietzke, Benjamin, Matthias Kiesner, Arne Berthold, Frank Haucke et Rudibert King. « Map Estimation for Impingement Cooling with a Fast Extremum Seeking Algorithm ». Dans Notes on Numerical Fluid Mechanics and Multidisciplinary Design, 367–78. Cham : Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-98177-2_23.

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El Ayadi, Nesrin, et Virginie Mamadouh. « Language Crossing, Fluid Identities, and Spatial Mobility : Representing Language, Identity, and Place in an Amsterdam-Based Movie ». Dans Handbook of the Changing World Language Map, 2381–98. Cham : Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-02438-3_184.

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Actes de conférences sur le sujet "MRP FLUID"

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Jha, Sunil, et V. K. Jain. « Evaluation of Rheological Properties of Magnetorheological Polishing Fluid and Their Effect on Surface Finish in Ultra Precision Finishing Processes ». Dans World Tribology Congress III. ASMEDC, 2005. http://dx.doi.org/10.1115/wtc2005-64260.

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Magnetorheological finishing (MRF) process for automated lens finishing and Magnetorheological abrasive flow finishing (MRAFF) for internal geometries rely on unique smart behavior of MRP-fluid. The rheological properties of MRP-fluid depend on carbonyl iron particle (CIP) and silicon carbide (SiC) particle size, their volume concentration, magnetic properties and applied magnetic field strength. To study the effect of particle size on rheological properties of MRP-fluid, a hydraulically driven specially designed capillary rheometer is fabricated. The best surface finish improvement was obtained with MRP-fluid containing approximately equal diameter of abrasive particles and CIPs. Least improvement was noticed with smaller CIPs and bigger abrasive combinations used. This is because the smaller size CIPs are incapable of providing the necessary finishing forces for bigger abrasive particles, which results in weak bonding strength.
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Ravnik, J., et L. Škerget. « BEM simulation of transient fluid flow phenomena ». Dans BEM/MRM 2011. Southampton, UK : WIT Press, 2011. http://dx.doi.org/10.2495/be110051.

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Dobashi, Yoshinori, Shoichi Hasegawa, Mitsuaki Kato, Makoto Sato, Tsuyoshi Yamamoto et Tomoyuki Nishita. « A fluid resistance map method for real-time haptic interaction with fluids ». Dans ACM SIGGRAPH 2005 Sketches. New York, New York, USA : ACM Press, 2005. http://dx.doi.org/10.1145/1187112.1187211.

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Dobashi, Yoshinori, Makoto Sato, Shoichi Hasegawa, Tsuyoshi Yamamoto, Mitsuaki Kato et Tomoyuki Nishita. « A fluid resistance map method for real-time haptic interaction with fluids ». Dans the ACM symposium. New York, New York, USA : ACM Press, 2006. http://dx.doi.org/10.1145/1180495.1180515.

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Cammarata, Robert. « On the Thermodynamics of Solid-Fluid Surfaces ». Dans 2008 MRS Fall Meetin. Materials Research Society, 2008. http://dx.doi.org/10.1557/proc-1152-tt02-02.

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GNITKO, VASYL I., ARTEM O. KARAIEV, KYRYL G. DEGTYARIOV, IVAN A. VIERUSHKIN et ELENA A. STRELNIKOVA. « SINGULAR AND HYPERSINGULAR INTEGRAL EQUATIONS IN FLUID–STRUCTURE INTERACTION ANALYSIS ». Dans BEM/MRM 45. Southampton UK : WIT Press, 2022. http://dx.doi.org/10.2495/be450061.

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Murphy, William M. « Secondary Minerals and Ambient Fluid Flow at Yucca Mountain ». Dans 2008 MRS Fall Meetin. Materials Research Society, 2008. http://dx.doi.org/10.1557/proc-1124-q08-06.

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Kelly, J. M., E. A. Divo et A. J. Kassab. « A GPU-accelerated meshless method for two-phase incompressible fluid flows ». Dans BEM/MRM 2013. Southampton, UK : WIT Press, 2013. http://dx.doi.org/10.2495/bem130021.

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Gnitko, V., V. Naumenko, U. Ogorodnyk et E. Strelnikova. « Coupled multi-domain BEM and FEM for fluid-structure interaction analysis ». Dans BEM/MRM 2013. Southampton, UK : WIT Press, 2013. http://dx.doi.org/10.2495/bem130041.

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Škerget, L., et J. Ravnik. « Numerical analysis of compressible fluid flow in a channel with sharp contractions ». Dans BEM/MRM 29. Southampton, UK : WIT Press, 2007. http://dx.doi.org/10.2495/be070181.

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Rapports d'organisations sur le sujet "MRP FLUID"

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Crawford, E. D. Magnetic Resonance Spectroscopy (MRS) of Prostatic Fluids for Early Detection of Prostate Cancer. Fort Belvoir, VA : Defense Technical Information Center, octobre 2005. http://dx.doi.org/10.21236/ada462810.

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King, E. L., A. Normandeau, T. Carson, P. Fraser, C. Staniforth, A. Limoges, B. MacDonald, F. J. Murrillo-Perez et N. Van Nieuwenhove. Pockmarks, a paleo fluid efflux event, glacial meltwater channels, sponge colonies, and trawling impacts in Emerald Basin, Scotian Shelf : autonomous underwater vehicle surveys, William Kennedy 2022011 cruise report. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/331174.

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A short but productive cruise aboard RV William Kennedy tested various new field equipment near Halifax (port of departure and return) but also in areas that could also benefit science understanding. The GSC-A Gavia Autonomous Underwater Vehicle equipped with bathymetric, sidescan and sub-bottom profiler was successfully deployed for the first time on Scotian Shelf science targets. It surveyed three small areas: two across known benthic sponge, Vazella (Russian Hat) within a DFO-directed trawling closure area on the SE flank of Sambro Bank, bordering Emerald Basin, and one across known pockmarks, eroded cone-shaped depression in soft mud due to fluid efflux. The sponge study sites (~ 150 170 m water depth) were known to lie in an area of till (subglacial diamict) exposure at the seabed. The AUV data identified gravel and cobble-rich seabed, registering individual clasts at 35 cm gridded resolution. A subtle variation in seabed texture is recognized in sidescan images, from cobble-rich on ridge crests and flanks, to limited mud-rich sediment in intervening troughs. Correlation between seabed topography and texture with the (previously collected) Vazella distribution along two transects is not straightforward. However there may be a preference for the sponge in the depressions, some of which have a thin but possibly ephemeral sediment cover. Both sponge study sites depict a hereto unknown morphology, carved in glacial deposits, consisting of a series of discontinuous ridges interpreted to be generated by erosion in multiple, continuous, meandering and cross-cutting channels. The morphology is identical to glacial Nye, or mp;lt;"N-mp;lt;"channels, cut by sub-glacial meltwater. However their scale (10 to 100 times mp;lt;"typicalmp;gt;" N-channels) and the unique eroded medium, (till rather than bedrock), presents a rare or unknown size and medium and suggests a continuum in sub-glacial meltwater channels between much larger tunnel valleys, common to the eastward, and the bedrock forms. A comparison is made with coastal Nova Scotia forms in bedrock. The Emerald Basin AUV site, targeting pockmarks was in ~260 to 270 m water depth and imaged eight large and one small pockmark. The main aim was to investigate possible recent or continuous fluid flux activity in light of ocean acidification or greenhouse gas contribution; most accounts to date suggested inactivity. While a lack of common attributes marking activity is confirmed, creep or rotational flank failure is recognized, as is a depletion of buried diffuse methane immediately below the seabed features. Discovery of a second, buried, pockmark horizon, with smaller but more numerous erosive cones and no spatial correlation to the buried diffuse gas or the seabed pockmarks, indicates a paleo-event of fluid or gas efflux; general timing and possible mechanisms are suggested. The basinal survey also registered numerous otter board trawl marks cutting the surficial mud from past fishing activity. The AUV data present a unique dataset for follow-up quantification of the disturbance. Recent realization that this may play a significant role in ocean acidification on a global scale can benefit from such disturbance quantification. The new pole-mounted sub-bottom profiler collected high quality data, enabling correlation of recently recognized till ridges exposed at the seabed as they become buried across the flank and base of the basin. These, along with the Nye channels, will help reconstruct glacial behavior and flow patterns which to date are only vaguely documented. Several cores provide the potential for stratigraphic dating of key horizons and will augment Holocene environmental history investigations by a Dalhousie University student. In summary, several unique features have been identified, providing sufficient field data for further compilation, analysis and follow-up publications.
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Patil et Cerkovnik. PR-425-123722-R01 Internally Lined Steel Risers as an Alternative to CRAs. Chantilly, Virginia : Pipeline Research Council International, Inc. (PRCI), octobre 2013. http://dx.doi.org/10.55274/r0010573.

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Carbon steel and low alloy steel are the common, cost effective materials of choice for design of production risers in deep water. They are, however, often challenged by high stress and fatigue loadings. When production fluids are corrosive and or sour, steel risers may not be feasible without the protection from corrosive effects. To mitigate degradation, the only proven solution to date is the use of corrosion resistant alloys (CRA), either in homogeneous or clad/lined steel pipe product. However, corrosion resistant alloys are very expensive and market supply is limited due to the number of developments worldwide requiring CRA solutions and the limited number mills capable of supplying the product. This study looks at the feasibility and current state of development of alternatives to clad steel in steel catenary risers (SCR). The study focuses on polymer liners and coatings as a way to prolong the life of the risers in corrosive hydrocarbon service. The study includes an industry survey of candidate liners and a risk assessment based on the threats and failure modes. FMECA is conducted on the more promising candidates. The gaps in the knowledge base are identified and a map of further qualification requirements is made. SCRs are currently fabricated with girth welds. However, there is significant amount of testing that indicates that mechanical connectors are a feasible alternative. The potential use of mechanical connectors in conjunction with a coating or liner solution to mitigate corrosion risks is also addressed.
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