The Experts below are selected from a list of 107082 Experts worldwide ranked by ideXlab platform
Robert M. Kacmarek - One of the best experts on this subject based on the ideXlab platform.
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set positive end expiratory Pressure during protective ventilation affects lung injury
Anesthesiology, 2002Co-Authors: Muneyuki Takeuchi, Dean R. Hess, Sven Goddon, Marisa Dolhnikoff, Motomu Shimaoka, Marcelo B P Amato, Robert M. KacmarekAbstract:Background: The most appropriate method of determining positive end-expiratory Pressure (PEEP) level during a lung protective ventilatory strategy has not been established. Methods: In a lavage-injured sheep acute respiratory distress syndrome model, the authors compared the effects of three approaches to determining PEEP level after a recruitment maneuver: (1) 2 cm H 2 O above the lower inflection point on the inflation Pressure-volume curve, (2) at the point of maximum curvature on the deflation Pressure-volume curve, and (3) at the PEEP level that maintained target arterial oxygen partial Pressure at a Fraction of inspired oxygen of 0.5. Results: Positive end-expiratory Pressure set 2 cm H 2 O above the lower inflection point resulted in the least injury over the course of the study. PEEP based on adequate arterial oxygen partial Pressure/Fraction of inspired oxygen ratios had to be increased over time and resulted in higher mRNA levels for interleukin-8 and interleukin-1β and greater tissue inflammation when compared with the other approaches. PEEP at the point of maximum curvature could not maintain eucapneia even at an increased ventilatory rate. Conclusion: Although generating higher plateau Pressures, PEEP levels based on Pressure-volume curve analysis were more effective in maintaining gas exchange and minimizing injury than PEEP based on adequate oxygenation. PEEP at 2 cm H 2 O above the lower inflection point was most effective.
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optimal mean airway Pressure during high frequency oscillation predicted by the Pressure volume curve
Anesthesiology, 2001Co-Authors: Sven Goddon, Yuji Fujino, Jonathan Hromi, Robert M. KacmarekAbstract:Background: A number of groups have recommended setting positive end-expiratory Pressure during conventional mechanical ventilation in adults at 2 cm H 2 O above the lower corner Pressure (P CL ) of the inspiratory Pressure-volume (P-V) curve of the respiratory system. No equivalent recommendations for the setting of the mean airway Pressure (P aw ) during high-frequency oscillation (HFO) exist. The authors questioned if the P aw resulting in the best oxygenation without hemodynamic compromise during HFO is related to the static P-V curve in a large animal model of acute respiratory distress syndrome. Methods: Saline lung lavage was performed in seven sheep (28 ± 5 kg, mean ± SD) until the arterial oxygen partial Pressure/Fraction of inspired oxygen ratio decreased to 85 ± 27 mmHg at a positive end-expiratory Pressure of 5 cm H 2 O (initial injury). The P CL (20 ± 1 cm H 2 O) on the inflation limb and the point of maximum curvature change (PMC; 26 ± 1 cm H 2 O) on the deflation limb of the static P-V curve were determined. The sheep were subjected to four 1-h cycles of HFO at different levels of P aw (P CL + 2, + 6, + 10, + 14 cm H 2 O), applied in random order. Each cycle was preceded by a recruitment maneuver at a sustained P aw of 50 cm H 2 O for 60 s. Results: High-frequency oscillation with a P aw of 6 cm H 2 O above P CL (P CL + 6) resulted in a significant improvement in oxygenation (P < 0.01 vs. initial injury). No further improvement in oxygenation was observed with higher P aw , but cardiac output decreased, pulmonary vascular resistance increased, and oxygen delivery decreased at P aw greater than P CL + 6. The PMC on the deflation limb of the P-V curve was equal to the P CL + 6 (r = 0.77, P < 0.05). Conclusion: In this model of acute respiratory distress syndrome, optimal P aw during HFO is equal to P CL + 6, which correlates with the PMC.
Du Guangchao - One of the best experts on this subject based on the ideXlab platform.
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Selective extraction of vanadium from pre-oxidized vanadium slag by carbochlorination in fluidized bed reactor
'Elsevier BV', 2019Co-Authors: Du Guangchao, Yang Haitao, Fan Chuanlin, Zhu QingshanAbstract:Most of the vanadium (V) is industrially extracted from vanadium slag, a byproduct in steelmaking, via the sodium roasting-water leaching or calcification roasting-acid leaching process, which usually suffers from environment pollution or decrease in product purity. In this paper, a novel process of vanadium extraction featuring carbochlorination of pre-oxidized vanadium slag with chlorine (Cl-2) and nitrogen (N-2) mixture in a fluidized bed reactor was proposed. And the selectivity between vanadium and iron (Fe) in the slag was primarily concerned, due to the high content of the latter in vanadium slag. The thermodynamic analysis reveals that there exists a favorable zone for selective chlorination of V from Fe compounds. Subsequently, carbochlorination experiments were conducted to investigate the influences of chlorination temperature and time, addition amount of petroleum coke and Pressure Fraction of chlorine on extraction of V and Fe. And 87.47% of V together with 18.79% of Fe can be extracted from the pre-oxidized vanadium slag by chlorination at 650 degrees C for 120 min with chlorine Pressure Fraction [P(Cl-2)/ P(Cl-2+N-2)] = 0.5 and petroleum coke mass Fraction in raw materials for chlorination Rc = 10%. The results demonstrate that the selective chlorination process has good potential to recover vanadium from vanadium slags in efficient and clean ways. (C) 2019 Elsevier Ltd. All rights reserved
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Selective extraction of vanadium from pre-oxidized vanadium slag by carbochlorination in fluidized bed reactor
Journal of Cleaner Production, 2019Co-Authors: Du Guangchao, Chuanlin Fan, Yang Haitao, Qingshan ZhuAbstract:Abstract Most of the vanadium (V) is industrially extracted from vanadium slag, a byproduct in steelmaking, via the sodium roasting-water leaching or calcification roasting-acid leaching process, which usually suffers from environment pollution or decrease in product purity. In this paper, a novel process of vanadium extraction featuring carbochlorination of pre-oxidized vanadium slag with chlorine (Cl2) and nitrogen (N2) mixture in a fluidized bed reactor was proposed. And the selectivity between vanadium and iron (Fe) in the slag was primarily concerned, due to the high content of the latter in vanadium slag. The thermodynamic analysis reveals that there exists a favorable zone for selective chlorination of V from Fe compounds. Subsequently, carbochlorination experiments were conducted to investigate the influences of chlorination temperature and time, addition amount of petroleum coke and Pressure Fraction of chlorine on extraction of V and Fe. And 87.47% of V together with 18.79% of Fe can be extracted from the pre-oxidized vanadium slag by chlorination at 650 °C for 120 min with chlorine Pressure Fraction [P(Cl2)/P(Cl2+N2)] = 0.5 and petroleum coke mass Fraction in raw materials for chlorination Rc = 10%. The results demonstrate that the selective chlorination process has good potential to recover vanadium from vanadium slags in efficient and clean ways.
Qingshan Zhu - One of the best experts on this subject based on the ideXlab platform.
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Selective extraction of vanadium from pre-oxidized vanadium slag by carbochlorination in fluidized bed reactor
Journal of Cleaner Production, 2019Co-Authors: Du Guangchao, Chuanlin Fan, Yang Haitao, Qingshan ZhuAbstract:Abstract Most of the vanadium (V) is industrially extracted from vanadium slag, a byproduct in steelmaking, via the sodium roasting-water leaching or calcification roasting-acid leaching process, which usually suffers from environment pollution or decrease in product purity. In this paper, a novel process of vanadium extraction featuring carbochlorination of pre-oxidized vanadium slag with chlorine (Cl2) and nitrogen (N2) mixture in a fluidized bed reactor was proposed. And the selectivity between vanadium and iron (Fe) in the slag was primarily concerned, due to the high content of the latter in vanadium slag. The thermodynamic analysis reveals that there exists a favorable zone for selective chlorination of V from Fe compounds. Subsequently, carbochlorination experiments were conducted to investigate the influences of chlorination temperature and time, addition amount of petroleum coke and Pressure Fraction of chlorine on extraction of V and Fe. And 87.47% of V together with 18.79% of Fe can be extracted from the pre-oxidized vanadium slag by chlorination at 650 °C for 120 min with chlorine Pressure Fraction [P(Cl2)/P(Cl2+N2)] = 0.5 and petroleum coke mass Fraction in raw materials for chlorination Rc = 10%. The results demonstrate that the selective chlorination process has good potential to recover vanadium from vanadium slags in efficient and clean ways.
Zhu Qingshan - One of the best experts on this subject based on the ideXlab platform.
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Selective extraction of vanadium from pre-oxidized vanadium slag by carbochlorination in fluidized bed reactor
'Elsevier BV', 2019Co-Authors: Du Guangchao, Yang Haitao, Fan Chuanlin, Zhu QingshanAbstract:Most of the vanadium (V) is industrially extracted from vanadium slag, a byproduct in steelmaking, via the sodium roasting-water leaching or calcification roasting-acid leaching process, which usually suffers from environment pollution or decrease in product purity. In this paper, a novel process of vanadium extraction featuring carbochlorination of pre-oxidized vanadium slag with chlorine (Cl-2) and nitrogen (N-2) mixture in a fluidized bed reactor was proposed. And the selectivity between vanadium and iron (Fe) in the slag was primarily concerned, due to the high content of the latter in vanadium slag. The thermodynamic analysis reveals that there exists a favorable zone for selective chlorination of V from Fe compounds. Subsequently, carbochlorination experiments were conducted to investigate the influences of chlorination temperature and time, addition amount of petroleum coke and Pressure Fraction of chlorine on extraction of V and Fe. And 87.47% of V together with 18.79% of Fe can be extracted from the pre-oxidized vanadium slag by chlorination at 650 degrees C for 120 min with chlorine Pressure Fraction [P(Cl-2)/ P(Cl-2+N-2)] = 0.5 and petroleum coke mass Fraction in raw materials for chlorination Rc = 10%. The results demonstrate that the selective chlorination process has good potential to recover vanadium from vanadium slags in efficient and clean ways. (C) 2019 Elsevier Ltd. All rights reserved
Sven Goddon - One of the best experts on this subject based on the ideXlab platform.
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set positive end expiratory Pressure during protective ventilation affects lung injury
Anesthesiology, 2002Co-Authors: Muneyuki Takeuchi, Dean R. Hess, Sven Goddon, Marisa Dolhnikoff, Motomu Shimaoka, Marcelo B P Amato, Robert M. KacmarekAbstract:Background: The most appropriate method of determining positive end-expiratory Pressure (PEEP) level during a lung protective ventilatory strategy has not been established. Methods: In a lavage-injured sheep acute respiratory distress syndrome model, the authors compared the effects of three approaches to determining PEEP level after a recruitment maneuver: (1) 2 cm H 2 O above the lower inflection point on the inflation Pressure-volume curve, (2) at the point of maximum curvature on the deflation Pressure-volume curve, and (3) at the PEEP level that maintained target arterial oxygen partial Pressure at a Fraction of inspired oxygen of 0.5. Results: Positive end-expiratory Pressure set 2 cm H 2 O above the lower inflection point resulted in the least injury over the course of the study. PEEP based on adequate arterial oxygen partial Pressure/Fraction of inspired oxygen ratios had to be increased over time and resulted in higher mRNA levels for interleukin-8 and interleukin-1β and greater tissue inflammation when compared with the other approaches. PEEP at the point of maximum curvature could not maintain eucapneia even at an increased ventilatory rate. Conclusion: Although generating higher plateau Pressures, PEEP levels based on Pressure-volume curve analysis were more effective in maintaining gas exchange and minimizing injury than PEEP based on adequate oxygenation. PEEP at 2 cm H 2 O above the lower inflection point was most effective.
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optimal mean airway Pressure during high frequency oscillation predicted by the Pressure volume curve
Anesthesiology, 2001Co-Authors: Sven Goddon, Yuji Fujino, Jonathan Hromi, Robert M. KacmarekAbstract:Background: A number of groups have recommended setting positive end-expiratory Pressure during conventional mechanical ventilation in adults at 2 cm H 2 O above the lower corner Pressure (P CL ) of the inspiratory Pressure-volume (P-V) curve of the respiratory system. No equivalent recommendations for the setting of the mean airway Pressure (P aw ) during high-frequency oscillation (HFO) exist. The authors questioned if the P aw resulting in the best oxygenation without hemodynamic compromise during HFO is related to the static P-V curve in a large animal model of acute respiratory distress syndrome. Methods: Saline lung lavage was performed in seven sheep (28 ± 5 kg, mean ± SD) until the arterial oxygen partial Pressure/Fraction of inspired oxygen ratio decreased to 85 ± 27 mmHg at a positive end-expiratory Pressure of 5 cm H 2 O (initial injury). The P CL (20 ± 1 cm H 2 O) on the inflation limb and the point of maximum curvature change (PMC; 26 ± 1 cm H 2 O) on the deflation limb of the static P-V curve were determined. The sheep were subjected to four 1-h cycles of HFO at different levels of P aw (P CL + 2, + 6, + 10, + 14 cm H 2 O), applied in random order. Each cycle was preceded by a recruitment maneuver at a sustained P aw of 50 cm H 2 O for 60 s. Results: High-frequency oscillation with a P aw of 6 cm H 2 O above P CL (P CL + 6) resulted in a significant improvement in oxygenation (P < 0.01 vs. initial injury). No further improvement in oxygenation was observed with higher P aw , but cardiac output decreased, pulmonary vascular resistance increased, and oxygen delivery decreased at P aw greater than P CL + 6. The PMC on the deflation limb of the P-V curve was equal to the P CL + 6 (r = 0.77, P < 0.05). Conclusion: In this model of acute respiratory distress syndrome, optimal P aw during HFO is equal to P CL + 6, which correlates with the PMC.
