It becomes increasingly clear that non-uniform distribution of immiscible fluids in porous rock is particularly relevant to seismic wave dispersion. White proposed a patchy saturation model in 1975, in which spherical...It becomes increasingly clear that non-uniform distribution of immiscible fluids in porous rock is particularly relevant to seismic wave dispersion. White proposed a patchy saturation model in 1975, in which spherical gas pockets were located at the center of a liquid saturated cube. For an extremely light and compressible inner gas, the physical properties can be approximated by a vacuum with White＇s model. The model successfully analyzes the dispersion phenomena of a P-wave velocity in gas-water- saturated rocks. In the case of liquid pocket saturation, e.g., an oil-pocket surrounded by a water saturated host matrix, the light fluid-pocket assumption is doubtful, and few works have been reported in White＇s framework. In this work, Poisson＇s ratio, the bulk modulus, and the effective density of a dual-liquid saturated medium are formulated for the heterogeneous porous rocks containing liquid-pockets. The analysis of the difference between the newly derived bulk modulus and that of White＇s model shows that the effects of liquid-pocket saturation do not disappear unless the porosity approaches zero. The inner pocket fluid can no longer be ignored. The improvements of the P-wave velocity predictions are illustrated with two examples taken from experiments, i.e., the P-wave velocity in the sandstone saturated by oil and brine and the P-wave velocity for heavy oils and stones at different temperatures.展开更多
Objective:To determine the characteristics of postprandial proximal gastric acid pockets(PPGAPs)and their association with gastroesophageal acid reflux in patients with Barrett’s esophagus(BE).Methods:Fifteen patient...Objective:To determine the characteristics of postprandial proximal gastric acid pockets(PPGAPs)and their association with gastroesophageal acid reflux in patients with Barrett’s esophagus(BE).Methods:Fifteen patients with BE(defined by columnar lined esophagus of≥1 cm)and 15 healthy individuals that were matched for age,gender,and body mass index,were recruited.The fasting intragastric p H and the appearance time,length,lowest p H,and mean p H of the PPGAP were determined using a single p H electrode pull-through experiment.For BE patients,a gastroesophageal reflux disease questionnaire(Gerd Q)was completed and esophageal 24-h p H monitoring was carried out.Results:The PPGAP was significantly longer(5(3,5)cm vs.2(1,2)cm)and the lowest p H(1.1(0.8,1.5)vs.1.6(1.4,1.9))was significantly lower in patients with short-segment BE than in healthy individuals.The PPGAP started to appear proximally from the gastroesophageal p H step-up point to the esophageal lumen.The acidity of the PPGAP was higher in the distal segment than in the proximal segment.In short-segment BE patients,there were significant correlations between the acidity and the appearance time and length of the PPGAP.The length and acidity of the PPGAP were positively associated with gastroesophageal acid reflux episodes.The acidity of the PPGAP was associated with the De Meester scores,the Gerd Q scores,and the fasting intragastric p H.Conclusions:In patients with short-segment BE,a PPGAP is commonly seen.Its length and acidity of PPGAP are associated with gastroesophageal acid reflux,the De Meester score,and the Gerd Q score in patients with short-segment BE.展开更多
基金Project supported by the Open Foundation of SINOPEC Key Laboratory of Geophysics(No.WTYJY-WX2013-04-02)the National Key Basic Research Program of China(973 Program)(No.2014CB239006)the 12th 5-Year Basic Research Program of China National Packaging Corporation(CNPC)(No.2014A-3611)
文摘It becomes increasingly clear that non-uniform distribution of immiscible fluids in porous rock is particularly relevant to seismic wave dispersion. White proposed a patchy saturation model in 1975, in which spherical gas pockets were located at the center of a liquid saturated cube. For an extremely light and compressible inner gas, the physical properties can be approximated by a vacuum with White＇s model. The model successfully analyzes the dispersion phenomena of a P-wave velocity in gas-water- saturated rocks. In the case of liquid pocket saturation, e.g., an oil-pocket surrounded by a water saturated host matrix, the light fluid-pocket assumption is doubtful, and few works have been reported in White＇s framework. In this work, Poisson＇s ratio, the bulk modulus, and the effective density of a dual-liquid saturated medium are formulated for the heterogeneous porous rocks containing liquid-pockets. The analysis of the difference between the newly derived bulk modulus and that of White＇s model shows that the effects of liquid-pocket saturation do not disappear unless the porosity approaches zero. The inner pocket fluid can no longer be ignored. The improvements of the P-wave velocity predictions are illustrated with two examples taken from experiments, i.e., the P-wave velocity in the sandstone saturated by oil and brine and the P-wave velocity for heavy oils and stones at different temperatures.
基金Project supported by the Natural Science Foundation of Inner Mongolia Autonomous Region(Nos.2019LH08042 and 2018MS08050)the Natural Science Foundation of Baotou Medical College(No.BYJJ-YF-2018024),China。
文摘Objective:To determine the characteristics of postprandial proximal gastric acid pockets(PPGAPs)and their association with gastroesophageal acid reflux in patients with Barrett’s esophagus(BE).Methods:Fifteen patients with BE(defined by columnar lined esophagus of≥1 cm)and 15 healthy individuals that were matched for age,gender,and body mass index,were recruited.The fasting intragastric p H and the appearance time,length,lowest p H,and mean p H of the PPGAP were determined using a single p H electrode pull-through experiment.For BE patients,a gastroesophageal reflux disease questionnaire(Gerd Q)was completed and esophageal 24-h p H monitoring was carried out.Results:The PPGAP was significantly longer(5(3,5)cm vs.2(1,2)cm)and the lowest p H(1.1(0.8,1.5)vs.1.6(1.4,1.9))was significantly lower in patients with short-segment BE than in healthy individuals.The PPGAP started to appear proximally from the gastroesophageal p H step-up point to the esophageal lumen.The acidity of the PPGAP was higher in the distal segment than in the proximal segment.In short-segment BE patients,there were significant correlations between the acidity and the appearance time and length of the PPGAP.The length and acidity of the PPGAP were positively associated with gastroesophageal acid reflux episodes.The acidity of the PPGAP was associated with the De Meester scores,the Gerd Q scores,and the fasting intragastric p H.Conclusions:In patients with short-segment BE,a PPGAP is commonly seen.Its length and acidity of PPGAP are associated with gastroesophageal acid reflux,the De Meester score,and the Gerd Q score in patients with short-segment BE.
