Combining improved injector, gas line and valve-driving models, a gas chromatograph (GC) equipped with Hydrogen Flame Ionization Detector (FID) and Electron Capture Detector (ECD), can measure CH4, CO2, and N2O simult...Combining improved injector, gas line and valve-driving models, a gas chromatograph (GC) equipped with Hydrogen Flame Ionization Detector (FID) and Electron Capture Detector (ECD), can measure CH4, CO2, and N2O simultaneously in an air sample in four minutes. Test results show that the system has high sensitivity, resolution, and precision; the linear response range of the system meets the requirement of flux measurements in situ. The system is suitable for monitoring fluxes of the main greenhouse gases in a short-plant field since it is easy to use, efficacious, and constant and reliable in collecting data.展开更多
The dynamics differential equations are constructed, and the initial conditions are also given. Simulation shows the following conclusions： The water pressure in cylinder has great instantaneous pulsation and phase s...The dynamics differential equations are constructed, and the initial conditions are also given. Simulation shows the following conclusions： The water pressure in cylinder has great instantaneous pulsation and phase step when outlet valve or inlet valve opens, but is more gently in other time; The volume efficiency is influenced by the output pressure slightly, and decreases as the working rotational speed increases; When the inherent frequency of the valves is integer multiple of the working frequency, the volume efficiency of system will decrease evidently.展开更多
Background Neovascular glaucoma （NVG） is a refractory disease which is difficult to manage. This study aimed at evaluating the efficacy and safety of adjunctive intravitreal bevacizumab （IVB） injection in conjunct...Background Neovascular glaucoma （NVG） is a refractory disease which is difficult to manage. This study aimed at evaluating the efficacy and safety of adjunctive intravitreal bevacizumab （IVB） injection in conjunction with Ahmed glaucoma valve implantation （AGVI） in the management of NVG. Methods This was a retrospective study of patients with NVG in whom AGVI was performed between October 2008 and May 2012. The sample was divided into two groups according to the pretreatment： with adjunctive IVB injection （the IVB group, n=25 eyes） and without adjunctive IVB injection （the control group, n=28 eyes）. The surgical success rate, number of antiglaucoma medications used, best-corrected visual acuity （BCVA）, postoperative complications, regression, and recurrence of iris neovascularization （NVI） were analyzed between the groups. Results The surgical outcomes of the two groups were compared. The complete success rates in the IVB and control groups were 84.0% and 64.3% at 12 months and 80.0% and 53.6% at 18 months, respectively. There was a significant difference between the two groups （P=0.041）. Mean postoperative intraocular pressures, mean number of postoperative antiglaucoma medications, and BCVA were not significant between the two groups. The NVI in 22 （88.0%） eyes had completely regressed within 2-8 days after IVB. However, NVI recurred in 10 eyes （40.0%） 2-9 months later after IVB. The IVB group had only 1 case （4.0%） of hyphema out of 25 eyes, while there were 8 （28.6%） cases of hyphema out of 28 eyes in the control group （P=0.026）.Conclusions This study showed that preoperative IVB injection reduced NVI remarkably, decreased hyphema, and led to higher surgical success rates. Pre-operative IVB injection may be an effective adjunct to AGVI in the management of NVG.展开更多
Objective： To investigate the protective effect of Shenfu Injection （参附注射液, SFI） against myocardium ischemia/reperfusion injury （IRI） in mitral valve replacement （MVR） with cardiopulmonary bypass （CPB）. ...Objective： To investigate the protective effect of Shenfu Injection （参附注射液, SFI） against myocardium ischemia/reperfusion injury （IRI） in mitral valve replacement （MVR） with cardiopulmonary bypass （CPB）. Metheds： Forty patients undergoing selective MVR were randomly assigned to the control group and trial Groups Ⅰ, Ⅱ,Ⅲ, and Ⅳ according to the different administrations of SFI, 8 patients in each group. The changes of systolic blood pressure （SBP）, mean blood pressure （MBP）, diastolic blood pressure （DBP） in each group were monitored, respectively. The recovering percentage of spontaneous heart beat, the heart rate （HR） and cardiac rhythm as well as the abnormal duration of ECG-ST segment were recorded after the restoration of heart beat. The serum concentration of cardiac troponin Ⅰ （cTnl）, malondialdehyde （MDA） and the activity of superoxide dismutase （SOD） were determined as well. Results： （1） The SBP, MBP and DBP values, the recovering rate of spontaneous heart beat, HR, ECG-ST, atrioventricular block and ventricular arrhythmia were significantly improved in group Ⅳ compared with any other groups. （2） Compared with the control group, the postoperative serum contents of cTnl and MDA were significantly decreased, but the activity of SOD was significantly increased in group Ⅳ. Cenclusiens： SFI had a certain protective effect against myocardium IRI. Moreover, better efficacy was seen with the administration of 1.5 mL/kg SFI into CPB priming fluid and pumping 1.5 mL/kg SFI via CPB as soon as the clamped aorta was unclamped.展开更多
Proportional direction valve is one of the most fundamental elements in electronic-hydraulic control technique. Its function is to control the operating speed, direction, position, and strength of output force of the ...Proportional direction valve is one of the most fundamental elements in electronic-hydraulic control technique. Its function is to control the operating speed, direction, position, and strength of output force of the hydraulic actuator continuously. Considering the different application and the cost, the existing technique mainly includes the internal feedback valve used in open loop system, and the electronic closed loop controlled valve used in closed loop system. Because of their different mechanical structure and the gre at different in performance, it brings inconvenience for customer to select, also inconvenience for enterprise to produce. Aiming at this problem, the idea of combining the above two kinds of valves into one body is proposed first, and then the new valve＇s structure to realize this target is designed. The idea intends to apply the displacement pilot flow feedback control principle in present 2-position 2-way valve system to the proportional direction valve of 3-position 4-way system. Newly designed feed forward controller can decouple the interference between the internal feedback and the electronic closed loop. Redundant conversion is designed to electronic switch mode. Experiment on dynamic and static characteristic of new proportional direction valve in internal feedback control mode and electronic closed loop control mode is discussed to prove the new theory is correct. Although the new valve is of excellent dynamic response characteristic, its steady control characteristic in open loop control mode needs to be improved further. The research results prepare one new fundamental element for electronic-hydraulic control technology.展开更多
文摘Combining improved injector, gas line and valve-driving models, a gas chromatograph (GC) equipped with Hydrogen Flame Ionization Detector (FID) and Electron Capture Detector (ECD), can measure CH4, CO2, and N2O simultaneously in an air sample in four minutes. Test results show that the system has high sensitivity, resolution, and precision; the linear response range of the system meets the requirement of flux measurements in situ. The system is suitable for monitoring fluxes of the main greenhouse gases in a short-plant field since it is easy to use, efficacious, and constant and reliable in collecting data.
基金This project is supported by National Natural Science Foundation of China(No.10342003).
文摘The dynamics differential equations are constructed, and the initial conditions are also given. Simulation shows the following conclusions： The water pressure in cylinder has great instantaneous pulsation and phase step when outlet valve or inlet valve opens, but is more gently in other time; The volume efficiency is influenced by the output pressure slightly, and decreases as the working rotational speed increases; When the inherent frequency of the valves is integer multiple of the working frequency, the volume efficiency of system will decrease evidently.
基金ZHOU Min-wen and WANG Wei contributed equallyto this study. This research was supported by grants from the National Natural Science Foundation of China （No. 81170849）, and the Fundamental Research Funds of State Key Laboratory of Ophthalmology （No. 2011 C02）.
文摘Background Neovascular glaucoma （NVG） is a refractory disease which is difficult to manage. This study aimed at evaluating the efficacy and safety of adjunctive intravitreal bevacizumab （IVB） injection in conjunction with Ahmed glaucoma valve implantation （AGVI） in the management of NVG. Methods This was a retrospective study of patients with NVG in whom AGVI was performed between October 2008 and May 2012. The sample was divided into two groups according to the pretreatment： with adjunctive IVB injection （the IVB group, n=25 eyes） and without adjunctive IVB injection （the control group, n=28 eyes）. The surgical success rate, number of antiglaucoma medications used, best-corrected visual acuity （BCVA）, postoperative complications, regression, and recurrence of iris neovascularization （NVI） were analyzed between the groups. Results The surgical outcomes of the two groups were compared. The complete success rates in the IVB and control groups were 84.0% and 64.3% at 12 months and 80.0% and 53.6% at 18 months, respectively. There was a significant difference between the two groups （P=0.041）. Mean postoperative intraocular pressures, mean number of postoperative antiglaucoma medications, and BCVA were not significant between the two groups. The NVI in 22 （88.0%） eyes had completely regressed within 2-8 days after IVB. However, NVI recurred in 10 eyes （40.0%） 2-9 months later after IVB. The IVB group had only 1 case （4.0%） of hyphema out of 25 eyes, while there were 8 （28.6%） cases of hyphema out of 28 eyes in the control group （P=0.026）.Conclusions This study showed that preoperative IVB injection reduced NVI remarkably, decreased hyphema, and led to higher surgical success rates. Pre-operative IVB injection may be an effective adjunct to AGVI in the management of NVG.
文摘Objective： To investigate the protective effect of Shenfu Injection （参附注射液, SFI） against myocardium ischemia/reperfusion injury （IRI） in mitral valve replacement （MVR） with cardiopulmonary bypass （CPB）. Metheds： Forty patients undergoing selective MVR were randomly assigned to the control group and trial Groups Ⅰ, Ⅱ,Ⅲ, and Ⅳ according to the different administrations of SFI, 8 patients in each group. The changes of systolic blood pressure （SBP）, mean blood pressure （MBP）, diastolic blood pressure （DBP） in each group were monitored, respectively. The recovering percentage of spontaneous heart beat, the heart rate （HR） and cardiac rhythm as well as the abnormal duration of ECG-ST segment were recorded after the restoration of heart beat. The serum concentration of cardiac troponin Ⅰ （cTnl）, malondialdehyde （MDA） and the activity of superoxide dismutase （SOD） were determined as well. Results： （1） The SBP, MBP and DBP values, the recovering rate of spontaneous heart beat, HR, ECG-ST, atrioventricular block and ventricular arrhythmia were significantly improved in group Ⅳ compared with any other groups. （2） Compared with the control group, the postoperative serum contents of cTnl and MDA were significantly decreased, but the activity of SOD was significantly increased in group Ⅳ. Cenclusiens： SFI had a certain protective effect against myocardium IRI. Moreover, better efficacy was seen with the administration of 1.5 mL/kg SFI into CPB priming fluid and pumping 1.5 mL/kg SFI via CPB as soon as the clamped aorta was unclamped.
基金supported by National Natural Science Foundation of China (Grant No. 50575156)Shanxi Provincial Natural Science Foundation of China (Grant No. 2008011053)
文摘Proportional direction valve is one of the most fundamental elements in electronic-hydraulic control technique. Its function is to control the operating speed, direction, position, and strength of output force of the hydraulic actuator continuously. Considering the different application and the cost, the existing technique mainly includes the internal feedback valve used in open loop system, and the electronic closed loop controlled valve used in closed loop system. Because of their different mechanical structure and the gre at different in performance, it brings inconvenience for customer to select, also inconvenience for enterprise to produce. Aiming at this problem, the idea of combining the above two kinds of valves into one body is proposed first, and then the new valve＇s structure to realize this target is designed. The idea intends to apply the displacement pilot flow feedback control principle in present 2-position 2-way valve system to the proportional direction valve of 3-position 4-way system. Newly designed feed forward controller can decouple the interference between the internal feedback and the electronic closed loop. Redundant conversion is designed to electronic switch mode. Experiment on dynamic and static characteristic of new proportional direction valve in internal feedback control mode and electronic closed loop control mode is discussed to prove the new theory is correct. Although the new valve is of excellent dynamic response characteristic, its steady control characteristic in open loop control mode needs to be improved further. The research results prepare one new fundamental element for electronic-hydraulic control technology.
