Underpressured reservoirs are widespread in the Huatugou （黄土沟） oUfield of the western uplift in Qaidam basin, western China. At depths between 462 and 1 248 m, the pressure of Neogene reservoirs in the Huatugou o...Underpressured reservoirs are widespread in the Huatugou （黄土沟） oUfield of the western uplift in Qaidam basin, western China. At depths between 462 and 1 248 m, the pressure of Neogene reservoirs in the Huatugou oUfield is only about 40% to 80% of hydrostatic pressure. Based on a study of the geological characteristics of these underpressured reservoirs, this work used fluid inclusion analysis and numerical simulation to investigate the mechanism creating these abnormal pressures and to evaluate the characteristics of the hydrocarbon distribution. The results show that the underpressured reservoirs are all well-sealed by undercompacted and thick mudrocks. The large-scale tectonic uplift in the late Himalayan plays an important role in the generation of underpressure in the Huatugou oilfield. At the beginning of this movement, the field was overpressured due to episodic petroleum accumulation. Later, structural uplift and erosion led to porous rebound and a temperature decrease, which produced the underpressure.展开更多
A generator to induce simulated underpressure of blast waves has been designed andapplied for the study of underpressure injuries in animals.The generator consists of a vacuumchamber,a vacuum pump,an experimental cham...A generator to induce simulated underpressure of blast waves has been designed andapplied for the study of underpressure injuries in animals.The generator consists of a vacuumchamber,a vacuum pump,an experimental chamber,a membrane-rupturing device,and apressure-measuring system.When the pressure in the vacuum chamber is reduced with the suc-tion of the vacuum pump to a given level,the membrane separating the vacuum chamber andthe experimental chamber,in which the experimental animal is fixed,is ruptured instantly by asharp pointer.Underpressure occurs in the experimental chamber as soon as its pressure is re-duced rapidly.The physical parameters of the simulated underpressure of blast waves rangefrom-13 to-90 kPa for the peak level,1 to 90 ms for the decreasing time and 14 to 2000 msfor the duration.Animal experimentation with the generator verified that underpressure can in-flict injuries on living bodies as well.展开更多
To explore the protective effects of earplug and barrel on auditory organs of guinea pigs exposed to experimental blast underpressure （BUP）. Methods： The hearing thresholds of the guinea pigs were assessed with au...To explore the protective effects of earplug and barrel on auditory organs of guinea pigs exposed to experimental blast underpressure （BUP）. Methods： The hearing thresholds of the guinea pigs were assessed with auditory brainstem responses （ABR）. The traumatic levels of tympanic membrane and ossicular chain were observed under stereo-microscope. The rate of outer hair cells （OHCs） loss was analyzed using a light microscope. The changes of guinea pigs protected with barrel and earplug were compared with those of the control group without any protection. Results： An important ABR threshold shift of the guinea pigs without any protection was detected from 8h to 14d after being exposed to BUP with a peak ranging from -64.5 kPa to -69.3 kPa （P〈0.01）. The rate of perforation of tympanic membrane reached 87.5 % and that of total OHCs loss was 19.46%± 5.38% at 14d after exposure. The guinea pigs protected with barrel and earplug had lower ABR threshold and total OHCs loss rate compared with the animals without any protection （P 〈0.01 ）. All of the tympanic membrane and ossicular chain of the protected animals maintained their integrities. Meanwhile, the guinea pigs protected with the barrel had lower ABR threshold and total OHCs loss rate than those with earplug （ P 〈 0.01 ）. Conclusions. The earplug and barrel have protective effects against BUP-induced trauma on auditory organs of the guinea pigs and the protective effects of barrel are better than those of earplug.展开更多
基金supported by the National Natural Science Foundation of China (Nos. 40802027, 40730422)the National Basic Research Program of China (973) (No. 2009CB219604)+1 种基金the Key Project of the National Science & Technology (No. 2008ZX05034)the Risk Innovation Foundation of PetroChina Co. Ltd. (No. 0706d01040102)
文摘Underpressured reservoirs are widespread in the Huatugou （黄土沟） oUfield of the western uplift in Qaidam basin, western China. At depths between 462 and 1 248 m, the pressure of Neogene reservoirs in the Huatugou oUfield is only about 40% to 80% of hydrostatic pressure. Based on a study of the geological characteristics of these underpressured reservoirs, this work used fluid inclusion analysis and numerical simulation to investigate the mechanism creating these abnormal pressures and to evaluate the characteristics of the hydrocarbon distribution. The results show that the underpressured reservoirs are all well-sealed by undercompacted and thick mudrocks. The large-scale tectonic uplift in the late Himalayan plays an important role in the generation of underpressure in the Huatugou oilfield. At the beginning of this movement, the field was overpressured due to episodic petroleum accumulation. Later, structural uplift and erosion led to porous rebound and a temperature decrease, which produced the underpressure.
基金This study was supported by the National Natural Science Fundation of China(NSFC)
文摘A generator to induce simulated underpressure of blast waves has been designed andapplied for the study of underpressure injuries in animals.The generator consists of a vacuumchamber,a vacuum pump,an experimental chamber,a membrane-rupturing device,and apressure-measuring system.When the pressure in the vacuum chamber is reduced with the suc-tion of the vacuum pump to a given level,the membrane separating the vacuum chamber andthe experimental chamber,in which the experimental animal is fixed,is ruptured instantly by asharp pointer.Underpressure occurs in the experimental chamber as soon as its pressure is re-duced rapidly.The physical parameters of the simulated underpressure of blast waves rangefrom-13 to-90 kPa for the peak level,1 to 90 ms for the decreasing time and 14 to 2000 msfor the duration.Animal experimentation with the generator verified that underpressure can in-flict injuries on living bodies as well.
文摘To explore the protective effects of earplug and barrel on auditory organs of guinea pigs exposed to experimental blast underpressure （BUP）. Methods： The hearing thresholds of the guinea pigs were assessed with auditory brainstem responses （ABR）. The traumatic levels of tympanic membrane and ossicular chain were observed under stereo-microscope. The rate of outer hair cells （OHCs） loss was analyzed using a light microscope. The changes of guinea pigs protected with barrel and earplug were compared with those of the control group without any protection. Results： An important ABR threshold shift of the guinea pigs without any protection was detected from 8h to 14d after being exposed to BUP with a peak ranging from -64.5 kPa to -69.3 kPa （P〈0.01）. The rate of perforation of tympanic membrane reached 87.5 % and that of total OHCs loss was 19.46%± 5.38% at 14d after exposure. The guinea pigs protected with barrel and earplug had lower ABR threshold and total OHCs loss rate compared with the animals without any protection （P 〈0.01 ）. All of the tympanic membrane and ossicular chain of the protected animals maintained their integrities. Meanwhile, the guinea pigs protected with the barrel had lower ABR threshold and total OHCs loss rate than those with earplug （ P 〈 0.01 ）. Conclusions. The earplug and barrel have protective effects against BUP-induced trauma on auditory organs of the guinea pigs and the protective effects of barrel are better than those of earplug.
