Kinetics of solid hydrate formation by carbon dioxide: Phase field theory of hydrate nucleation and magnetic resonance imaging

2004 ◽  
Vol 6 (9) ◽  
pp. 2327-2334 ◽  
Author(s):  
B. Kvamme ◽  
A. Graue ◽  
E. Aspenes ◽  
T. Kuznetsova ◽  
L. Gránásy ◽  
...  
2021 ◽  
Vol 5 (5) ◽  
pp. 1567-1583 ◽  
Author(s):  
Mehrdad Vasheghani Farahani ◽  
Xianwei Guo ◽  
Lunxiang Zhang ◽  
Mingzhao Yang ◽  
Aliakbar Hassanpouryouzband ◽  
...  

A magnetic resonance imaging study was conducted to explore the kinetics and spatial characteristics of the thermally induced methane hydrate formation in both synthetic and natural sediment samples.


1998 ◽  
Vol 88 (4) ◽  
pp. 984-992 ◽  
Author(s):  
Jean-Francois Payen ◽  
Albert Vath ◽  
Blanche Koenigsberg ◽  
Virginie Bourlier ◽  
Michel Decorps

Background Noninvasive techniques used to determine the changes in cerebral blood volume in response to carbon dioxide are hampered by their limited spatial or temporal resolution or both. Using steady state contrast-enhanced magnetic resonance imaging, the authors determined regional changes in cerebral plasma volume (CPV) induced by hypercapnia in halothane-anesthetized rats. Methods Cerebral plasma volume was determined during normocapnia, hypercapnia and recovery in the dorsoparietal neocortex and striatum of each hemisphere, in cerebellum, and in extracerebral tissue of rats with either intact carotid arteries (group 1) or unilateral common carotid ligation (group 2). Another group was studied without injection of a contrast agent (group 3). Results Hypercapnia (partial pressure of carbon dioxide in arterial blood [PaCO2] approximately 65 mmHg) resulted in a significant increase in CPV in the striatum (+42 +/- 8%), neocortex (+34 +/- 6%), and cerebellum (+49 +/- 12%) compared with normocapnic CPV values (group 1). Carotid ligation (group 2) led to a marked reduction of the CPV response to hypercapnia in the ipsilateral striatum (+23 +/- 14%) and neocortex (+27 +/- 17%) compared with the unclamped side (+34 +/- 15% and +38 +/- 16%, respectively). No significant changes in CPV were found in extracerebral tissue. In both groups, the CPV changes were reversed by the carbon dioxide washout period. Negligible changes in contrast imaging were detected during hypercapnia without administration of the contrast agent (group 3). Conclusions The contrast-enhanced magnetic resonance imaging technique is sensitive to detect noninvasively regional CPV changes induced by hypercapnia in rat brain. This could be of clinical interest for determining the cerebrovascular reactivity among different brain regions.


SPE Journal ◽  
2018 ◽  
Vol 23 (03) ◽  
pp. 772-787 ◽  
Author(s):  
Armin Afrough ◽  
M.. Shakerian ◽  
M. S. Zamiri ◽  
Bryce MacMillan ◽  
Florea Marica ◽  
...  

Summary Magnetic-resonance imaging (MRI) provides a wealth of information on petroleum-flooding-displacement mechanisms and in-situ pore-level behavior. This study demonstrates MRI methods that have potential for studying the mechanisms of carbon dioxide (CO2) displacement processes in Berea core plugs during the recovery of decane and heavy oil. The correlation between fluid saturation and transverse relaxation time (T2) revealed the contrast in decane/pore-surface interaction between miscible and immiscible drainage of decane by CO2. T2 profiles demonstrated changes in the composition and viscosity of the heavy oil caused by the extraction of light components by CO2.


2020 ◽  
Vol 2 (2) ◽  
Author(s):  
Carissa L Patete ◽  
Michael Plastini ◽  
Prakash J Mathew ◽  
Jason J Yoo ◽  
Zubin Panthaki

Abstract Implant-based reconstruction is the most common form of breast reconstruction following mastectomy. It is most often performed in 2 stages using saline-based tissue expanders, which are then exchanged for permanent implants. Serial expansions are performed by accessing a port in the office, an inconvenient and sometimes painful process. A carbon dioxide tissue expander is a device that provides a needle-free, patient-controlled expansion utilizing a remote-controlled CO2 canister. While a patient-controlled expansion offers convenience, given that the CO2 reservoir holds approximately 1500 mL of gas, the potential for malfunction resulting in an uncontrolled expansion in unique to this device. The authors present a case report of a patient with bilateral pre-pectoral tissue expanders who underwent magnetic resonance imaging, resulting in uncontrolled expansion. Level of Evidence: 5


2011 ◽  
Vol 25 (7) ◽  
pp. 3083-3092 ◽  
Author(s):  
S. Alireza Bagherzadeh ◽  
Igor L. Moudrakovski ◽  
John A. Ripmeester ◽  
Peter Englezos

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