PetroChina seized the favorable opportunity when the international oil price was raising and the domestic market demand in China was strong to enlarge production and optimize the operation management actively in the f...PetroChina seized the favorable opportunity when the international oil price was raising and the domestic market demand in China was strong to enlarge production and optimize the operation management actively in the first half of this year, which making it＇s all indicators of the production and operation see fully upgraded and enabling sustainable rapid and effective development.展开更多
Objective To choose one optimal extrinsic positive end-expiratory pressure (PEEPe) for ventilated patients with chronic obstructive pulmonary disease (COPD) and to compare two methods for choosing the optimal level o...Objective To choose one optimal extrinsic positive end-expiratory pressure (PEEPe) for ventilated patients with chronic obstructive pulmonary disease (COPD) and to compare two methods for choosing the optimal level of PEEPe.Methods Ten ventilated patients with COPD were included in the study. First, static intrinsic positive end-expiratory pressure (PEEPi,st) was measured when PEEPe was zero, and the PEEPi,st was called PEEPi,stz. PEEPe at 0%, 40%, 50%, 60%, 70%, 80%, 90% and 100% of PEEPi,stz, respectively, were applied randomly. Respiratory mechanics, hemodynamics, and oxygen dynamics were recorded 30 minutes after the level of PEEPe was changed.Results When PEEPe was not higher than 80% of PEEPi,stz, no measurement changed significantly. When PEEPe was increased to 90% and 100% of PEEPi,stz, PEEPi,st, peak inspiratory pressure, plateau pressure, pulmonary capillary wedge pressure and central venous pressure increased significantly, P<0.01. Cardiac output and left ventricular work index decreased significantly, P<0.01. Oxygen delivery decreased significantly, P<0.05. When PEEPe was increased to 100% of PEEPi,stz, the right ventricular work index decreased significantly, P<0.05.Conclusion Eighty percent of PEEPi,stz was the upper limit of PEEPe. The results of the two methods used to set the level of PEEPe were identical.展开更多
Objective To investigate the effects of extrinsic positive end-expiratory pressure (PEEPe) on work of breathing in patients with chronic obstructive pulmonary disease (COPD) and their corresponding mechanism.Methods...Objective To investigate the effects of extrinsic positive end-expiratory pressure (PEEPe) on work of breathing in patients with chronic obstructive pulmonary disease (COPD) and their corresponding mechanism.Methods Ten ventilated patients with COPD were included in the study. A Bicore CP-100 pulmonary monitor (Bicore Monitoring System, USA) was used for monitoring respiratory mechanics. First, dynamic intrinsic positive end-expiratory pressure (PEEPi,dyn) was measured when PEEPe was zero, which was called PEEPi,dynz. Then the PEEPe was set randomly at 0%, 40%, 60%, 80% and 100% of PEEPi,dynz respectively. Pulmonary mechanics and other parameters (heart rate, blood pressure and blood gas analysis) were measured 30 minutes after the level of PEEPe was changed.Results Work of breathing patient (WOBp), pressure time product, difference of esophageal pressure and PEEPi,dyn decreased significantly when PEEPe was applied, and continued decreasing as PEEPe was increased. Work of breathing ventilator increased significantly when PEEPe was increased to 80% and 100% of PEEPi,dynz. Significantly positive linear correlation was found between the changes in WOBp and in PEEPi,dyn.Conclusions WOBp decreases gradually as PEEPe is increased. WOBp decreases by narrowing the difference between the alveolus pressure and the central airway pressure at the end of expiration when PEEPe is applied.展开更多
A new self-powered active gas sensor for realtime monitoring of automotive exhaust gas was devised.The pipe-shaped device was fabricated from polydimethylsiloxane/polypyrrole(PDMS/Ppy)triboelectric gas-sensing unit ar...A new self-powered active gas sensor for realtime monitoring of automotive exhaust gas was devised.The pipe-shaped device was fabricated from polydimethylsiloxane/polypyrrole(PDMS/Ppy)triboelectric gas-sensing unit arrays.The gas-sensing units can actively convert the mechanical energy of gas flow into a triboelectric current.The output current signal depends on the species and concentrations of the target chemical gases(CO,NH3,NO)in the gas flow,and thus can be used as a sensing signal.The device consists of seven gas-sensing units with different Ppy derivatives.As the different sensing units respond to the gases in different ways,the device can differentiate between gas species.The working mechanism is attributed to the coupling effect between the triboelectric effect of PDMS/Ppy and the gas-sensing properties of Ppy.The device can be installed in the tailpipe of an automobile,and can thus analyze the exhaust gas in real time without the need for any external electrical power.The results of the present study spur a new research direction for the development of automotive exhaust gas monitoring systems,thus playing an important role in the detection of air pollution.展开更多
文摘PetroChina seized the favorable opportunity when the international oil price was raising and the domestic market demand in China was strong to enlarge production and optimize the operation management actively in the first half of this year, which making it＇s all indicators of the production and operation see fully upgraded and enabling sustainable rapid and effective development.
文摘Objective To choose one optimal extrinsic positive end-expiratory pressure (PEEPe) for ventilated patients with chronic obstructive pulmonary disease (COPD) and to compare two methods for choosing the optimal level of PEEPe.Methods Ten ventilated patients with COPD were included in the study. First, static intrinsic positive end-expiratory pressure (PEEPi,st) was measured when PEEPe was zero, and the PEEPi,st was called PEEPi,stz. PEEPe at 0%, 40%, 50%, 60%, 70%, 80%, 90% and 100% of PEEPi,stz, respectively, were applied randomly. Respiratory mechanics, hemodynamics, and oxygen dynamics were recorded 30 minutes after the level of PEEPe was changed.Results When PEEPe was not higher than 80% of PEEPi,stz, no measurement changed significantly. When PEEPe was increased to 90% and 100% of PEEPi,stz, PEEPi,st, peak inspiratory pressure, plateau pressure, pulmonary capillary wedge pressure and central venous pressure increased significantly, P<0.01. Cardiac output and left ventricular work index decreased significantly, P<0.01. Oxygen delivery decreased significantly, P<0.05. When PEEPe was increased to 100% of PEEPi,stz, the right ventricular work index decreased significantly, P<0.05.Conclusion Eighty percent of PEEPi,stz was the upper limit of PEEPe. The results of the two methods used to set the level of PEEPe were identical.
文摘Objective To investigate the effects of extrinsic positive end-expiratory pressure (PEEPe) on work of breathing in patients with chronic obstructive pulmonary disease (COPD) and their corresponding mechanism.Methods Ten ventilated patients with COPD were included in the study. A Bicore CP-100 pulmonary monitor (Bicore Monitoring System, USA) was used for monitoring respiratory mechanics. First, dynamic intrinsic positive end-expiratory pressure (PEEPi,dyn) was measured when PEEPe was zero, which was called PEEPi,dynz. Then the PEEPe was set randomly at 0%, 40%, 60%, 80% and 100% of PEEPi,dynz respectively. Pulmonary mechanics and other parameters (heart rate, blood pressure and blood gas analysis) were measured 30 minutes after the level of PEEPe was changed.Results Work of breathing patient (WOBp), pressure time product, difference of esophageal pressure and PEEPi,dyn decreased significantly when PEEPe was applied, and continued decreasing as PEEPe was increased. Work of breathing ventilator increased significantly when PEEPe was increased to 80% and 100% of PEEPi,dynz. Significantly positive linear correlation was found between the changes in WOBp and in PEEPi,dyn.Conclusions WOBp decreases gradually as PEEPe is increased. WOBp decreases by narrowing the difference between the alveolus pressure and the central airway pressure at the end of expiration when PEEPe is applied.
基金supported by the National Natural Science Foundation of China (11674048)the Fundamental Research Funds for the Central Universities (N170505001 and N160502002)the Program for Shenyang Youth Science and Technology Innovation Talents (RC170269)
文摘A new self-powered active gas sensor for realtime monitoring of automotive exhaust gas was devised.The pipe-shaped device was fabricated from polydimethylsiloxane/polypyrrole(PDMS/Ppy)triboelectric gas-sensing unit arrays.The gas-sensing units can actively convert the mechanical energy of gas flow into a triboelectric current.The output current signal depends on the species and concentrations of the target chemical gases(CO,NH3,NO)in the gas flow,and thus can be used as a sensing signal.The device consists of seven gas-sensing units with different Ppy derivatives.As the different sensing units respond to the gases in different ways,the device can differentiate between gas species.The working mechanism is attributed to the coupling effect between the triboelectric effect of PDMS/Ppy and the gas-sensing properties of Ppy.The device can be installed in the tailpipe of an automobile,and can thus analyze the exhaust gas in real time without the need for any external electrical power.The results of the present study spur a new research direction for the development of automotive exhaust gas monitoring systems,thus playing an important role in the detection of air pollution.
