In order to inhibit hydrogen evolution and enhance current efficiency of Zn-Fe alloy electrodeposition from alkaline zincate solution, hydrogen inhibitors composed of the sulfur group elements were optimized on the ba...In order to inhibit hydrogen evolution and enhance current efficiency of Zn-Fe alloy electrodeposition from alkaline zincate solution, hydrogen inhibitors composed of the sulfur group elements were optimized on the basis of atom structures analysis. The effects of hydrogen inhibitor on the current efficiency of Zn-Fe alloy electroplating and their electrochemical behaviors were studied. The results indicate that hydrogen inhibitor can increase the current efficiency of Zn-Fe alloy electroplating evidently, from 63.28% without hydrogen inhibitor up to 83.54% with a hydrogen inhibitor at a volume fraction of 2.0%, while it has a minor influence on that of pure Zn plating, which maintains at 80%. The optimum volume fraction of hydrogen inhibitor is 2.0%.展开更多
The effect of hydrogen inhibitor on partial current densities of Zn, Fe and differential capacitance of electrodeelectrolyte interface, and adsorbing type of hydrogen inhibitor were studied by the methods of electroch...The effect of hydrogen inhibitor on partial current densities of Zn, Fe and differential capacitance of electrodeelectrolyte interface, and adsorbing type of hydrogen inhibitor were studied by the methods of electrochemistry. The mechanism of current efficiency improvement were explained from the point of valence electron theory. The results indicate that the partial current density of Fe increases in addition of hydrogen inhibitor, which reaches the maximum of 0.14 Adm2 when current density is 0.2 Adm2. Differential capacitance of electrodeelectrolyte interface decreases obviously from 20.3 μFcm2 to 7 μFcm2 rapidly with the concentration varying from 0 to 20 mLL, because hydrogen inhibitor chemically adsorbs on active points of Fe electrode surface selectively. Element S in hydrogen inhibitor with negative electricity and strong capacity of offering electron shares isolated electrons with Fe. The adsorption of H atom is inhibited when adsorbing on active points of Fe electrode surface firstly, and then current efficiency of Zn-Fe alloy electroplating is improved accordingly.展开更多
Objective To test the resuscitative effects from prolonged ventricular fibrillation by epinephrine combined with sodium hydrogen exchanger isoform 1 inhibitor Cariporide. Methods 16 rats were received a 3 mg/kg bolu...Objective To test the resuscitative effects from prolonged ventricular fibrillation by epinephrine combined with sodium hydrogen exchanger isoform 1 inhibitor Cariporide. Methods 16 rats were received a 3 mg/kg bolus of Cariporide or the same volume of 0.9%NaCl solution (control) 15 seconds before completion 12 minutes untreated VF. Chest compression (CC) was started for a total of 8 minutes. Adjusted the depth of compressor so that the aortic diastolic pressure to 25~28 mmHg during the 2nd minute of CC. Fix the depth of the piston and this depth was used throughout the remaining 6 minutes of CC. 10 seconds before starting the 3rd minute of chest compression, injected epinephrine (30 μg/kg). Recorded the time at which restoration of spontaneous circulation (ROSC) occurred in Cariporide treated rats. Electrical defibrillation was timed in control group to match the time of spontaneous defibrillation in Cariporide treated rats. To the rats, which cant be defibrillated spontaneously, received chest compression and rescues electrical shocks. Results compared with control group, with the same CC depth, Cariporide treated rats received the higher and longer lasting coronary perfusion pressure (P< 0.05), higher resuscitative rate (P< 0.05), less post resuscitative ventricular ectopic activities (P< 0.001), better hemodynamic effects and longer survival time (P< 0.05). Conclusion Epinephrine combined with sodium hydrogen exchanger isoform 1 inhibitor Cariporide may represent a novel and remarkably effective intervention for resuscitation from prolonged VF.展开更多
Myeloperoxidase (MPO) is a neutrophil enzyme that employs hydrogen peroxide (H2O2) to catalyze the oxidation of chloride (Cl–) to hypochlorous acid (HOCl). Accepted mechanism is based on rapid reaction of native MPO ...Myeloperoxidase (MPO) is a neutrophil enzyme that employs hydrogen peroxide (H2O2) to catalyze the oxidation of chloride (Cl–) to hypochlorous acid (HOCl). Accepted mechanism is based on rapid reaction of native MPO with H2O2to produce Compound I (MPO-I) which oxidizes Cl– through a 2e– transition generating MPO and HOCl. MPO-I also reacts with H2O2 to generate Compound II (MPO-II) which is inactive in 2e oxidation of Cl–. Nitrite ( NO2-) inhibits the 2e oxidation of Cl– by reaction with MPO-I through 1e transition generating MPO-II and nitrite radical. H2O2 consumption during steady- state catalysis was monitored amperometrically by a carbon fiber based H2O2-biosensor at 25oC. Results demonstrated that in absence of NO2- reactions were monophasic and rapid (complete H2O2 consumption occurs in 2- increases, reactions change to biphasic (rapid step followed by a slow step) and both steps have been inhibited by NO2- . A predictive kinetic model describing the inhibittory effect of NO2- was developed and applied to experimental results The model is based on the assumption that MPO–I cannot be detected during steady-state catalysis. Calculated rate constants are in agreement with those obtained from pre-steady state kinetic methods.展开更多
Capsid protein enterovirus 71 (EV71) is one of the major viruses that cause the severe encephalitis and thus result in a high mortality in children less than 5 years of age.In an effort to discover new potent inhibi...Capsid protein enterovirus 71 (EV71) is one of the major viruses that cause the severe encephalitis and thus result in a high mortality in children less than 5 years of age.In an effort to discover new potent inhibitors against EV71,a novel three-dimensional pharmacophore model was developed on 24 inhibitors with different molecular structures and bioactivities.The best hypothesis (Hypo1) has a high predictive power and consists of four features,namely,one hydrophobic point (HY) and three hydrogen-bond acceptors (HA).Two key features of the best Hypo1,HY1 and HA3 match well with an important narrow hydrophobic canyon and with the surface of LYS274 in the target EV71 active site,respectively.The more versatile feature,HA1,is firstly found to be very influential on these compounds’ bioactivities,which may interact with the other side of the active site in the EV71 receptor.The application of the model is successful in predicting the activities of 30 known EV71 inhibitors with a correlation coefficient of 0.831.Furthermore,Hypo1 demonstrates a superior screening capability for retrieving inhibitors from the database with a high enrichment factor of 70.This study provides some important clues in search for more potent inhibitors against EV71 infection.展开更多
基金Project(50274073) supported by the National Natural Science Foundation of China
文摘In order to inhibit hydrogen evolution and enhance current efficiency of Zn-Fe alloy electrodeposition from alkaline zincate solution, hydrogen inhibitors composed of the sulfur group elements were optimized on the basis of atom structures analysis. The effects of hydrogen inhibitor on the current efficiency of Zn-Fe alloy electroplating and their electrochemical behaviors were studied. The results indicate that hydrogen inhibitor can increase the current efficiency of Zn-Fe alloy electroplating evidently, from 63.28% without hydrogen inhibitor up to 83.54% with a hydrogen inhibitor at a volume fraction of 2.0%, while it has a minor influence on that of pure Zn plating, which maintains at 80%. The optimum volume fraction of hydrogen inhibitor is 2.0%.
基金Projects(50274073) supported by the National Natural Science Foundation of China
文摘The effect of hydrogen inhibitor on partial current densities of Zn, Fe and differential capacitance of electrodeelectrolyte interface, and adsorbing type of hydrogen inhibitor were studied by the methods of electrochemistry. The mechanism of current efficiency improvement were explained from the point of valence electron theory. The results indicate that the partial current density of Fe increases in addition of hydrogen inhibitor, which reaches the maximum of 0.14 Adm2 when current density is 0.2 Adm2. Differential capacitance of electrodeelectrolyte interface decreases obviously from 20.3 μFcm2 to 7 μFcm2 rapidly with the concentration varying from 0 to 20 mLL, because hydrogen inhibitor chemically adsorbs on active points of Fe electrode surface selectively. Element S in hydrogen inhibitor with negative electricity and strong capacity of offering electron shares isolated electrons with Fe. The adsorption of H atom is inhibited when adsorbing on active points of Fe electrode surface firstly, and then current efficiency of Zn-Fe alloy electroplating is improved accordingly.
文摘Objective To test the resuscitative effects from prolonged ventricular fibrillation by epinephrine combined with sodium hydrogen exchanger isoform 1 inhibitor Cariporide. Methods 16 rats were received a 3 mg/kg bolus of Cariporide or the same volume of 0.9%NaCl solution (control) 15 seconds before completion 12 minutes untreated VF. Chest compression (CC) was started for a total of 8 minutes. Adjusted the depth of compressor so that the aortic diastolic pressure to 25~28 mmHg during the 2nd minute of CC. Fix the depth of the piston and this depth was used throughout the remaining 6 minutes of CC. 10 seconds before starting the 3rd minute of chest compression, injected epinephrine (30 μg/kg). Recorded the time at which restoration of spontaneous circulation (ROSC) occurred in Cariporide treated rats. Electrical defibrillation was timed in control group to match the time of spontaneous defibrillation in Cariporide treated rats. To the rats, which cant be defibrillated spontaneously, received chest compression and rescues electrical shocks. Results compared with control group, with the same CC depth, Cariporide treated rats received the higher and longer lasting coronary perfusion pressure (P< 0.05), higher resuscitative rate (P< 0.05), less post resuscitative ventricular ectopic activities (P< 0.001), better hemodynamic effects and longer survival time (P< 0.05). Conclusion Epinephrine combined with sodium hydrogen exchanger isoform 1 inhibitor Cariporide may represent a novel and remarkably effective intervention for resuscitation from prolonged VF.
文摘Myeloperoxidase (MPO) is a neutrophil enzyme that employs hydrogen peroxide (H2O2) to catalyze the oxidation of chloride (Cl–) to hypochlorous acid (HOCl). Accepted mechanism is based on rapid reaction of native MPO with H2O2to produce Compound I (MPO-I) which oxidizes Cl– through a 2e– transition generating MPO and HOCl. MPO-I also reacts with H2O2 to generate Compound II (MPO-II) which is inactive in 2e oxidation of Cl–. Nitrite ( NO2-) inhibits the 2e oxidation of Cl– by reaction with MPO-I through 1e transition generating MPO-II and nitrite radical. H2O2 consumption during steady- state catalysis was monitored amperometrically by a carbon fiber based H2O2-biosensor at 25oC. Results demonstrated that in absence of NO2- reactions were monophasic and rapid (complete H2O2 consumption occurs in 2- increases, reactions change to biphasic (rapid step followed by a slow step) and both steps have been inhibited by NO2- . A predictive kinetic model describing the inhibittory effect of NO2- was developed and applied to experimental results The model is based on the assumption that MPO–I cannot be detected during steady-state catalysis. Calculated rate constants are in agreement with those obtained from pre-steady state kinetic methods.
基金Sponsored by the National Natural Science Foundation of China (No. 30800719)
文摘Capsid protein enterovirus 71 (EV71) is one of the major viruses that cause the severe encephalitis and thus result in a high mortality in children less than 5 years of age.In an effort to discover new potent inhibitors against EV71,a novel three-dimensional pharmacophore model was developed on 24 inhibitors with different molecular structures and bioactivities.The best hypothesis (Hypo1) has a high predictive power and consists of four features,namely,one hydrophobic point (HY) and three hydrogen-bond acceptors (HA).Two key features of the best Hypo1,HY1 and HA3 match well with an important narrow hydrophobic canyon and with the surface of LYS274 in the target EV71 active site,respectively.The more versatile feature,HA1,is firstly found to be very influential on these compounds’ bioactivities,which may interact with the other side of the active site in the EV71 receptor.The application of the model is successful in predicting the activities of 30 known EV71 inhibitors with a correlation coefficient of 0.831.Furthermore,Hypo1 demonstrates a superior screening capability for retrieving inhibitors from the database with a high enrichment factor of 70.This study provides some important clues in search for more potent inhibitors against EV71 infection.