Methane conversion to C2 hydrocarbons has been investigated with the addition of hydrogen in a plasma reactor of abnormal glow discharge at atmospheric pressure. The aim of this experiment is to minimize coke formatio...Methane conversion to C2 hydrocarbons has been investigated with the addition of hydrogen in a plasma reactor of abnormal glow discharge at atmospheric pressure. The aim of this experiment is to minimize coke formation and improve discharge stability. The typical conditions in the experiment are 300 ml of total feed flux and 400 W of discharge power. The experimental results show that methane conversion is from 91.6% to 35.2% in mol, acetylene selectivity is from 90.2% to 57.6%, and ethylene selectivity is approximately from 7.8% to 3.6%, where the coke increases gradually along with the increase of CH4/H2 from 2 : 8 to 9 : 1. A stable discharge for a considerable running time can be obtained only at a lower ratio of CH4/H2 = 2:8 or 3: 7. These phenomena indicate that the coke deposition during methane conversion is obviously reduced by adding a large amount of hydrogen during an abnormal glow discharge. A qualitative interpretation is presented, namely, with abundant hydrogen, the possibility that hydrogen molecules are activated to hydrogen radicals is increased with the help of the abnormal glow discharge. These hydrogen radicals react with carbon radicals to form C2 hydrocarbon products. Therefore, the deposition of coke is restrained.展开更多
Propylene carbonate (PC) has a great potential to be used as an energy storage medium in the compact pulsed power sources due to its high dielectric constant and large resistivity. We investigate both the positive a...Propylene carbonate (PC) has a great potential to be used as an energy storage medium in the compact pulsed power sources due to its high dielectric constant and large resistivity. We investigate both the positive and negative breakdown characteristics of PC. The streamer patterns are obtained by ultra-high-speed cameras. The experimental results show that the positive breakdown voltage of PC is about 135% higher than the negative one, which is abnormal compared with the common liquid. The shape of the positive streamer is filamentary and branchy, while the negative streamer is tree-like and less branched. According to these experimental results, a charge layer structure model at the interface between the metal electrode and liquid is presented. It is suggested that the abnormal polarity effect basically arises from the electric field strength difference in the interface between both electrodes and PC. What is more, the recombination radiation and photoionization also play an important role in the whole discharge process.展开更多
Atmospheric pressure abnormal glow discharge (APAGD) was carried out simply with a transformer of 1 : 500 driven by a alternating current with a frequency of 50 Hz. Typical stable discharge parameters, namely volta...Atmospheric pressure abnormal glow discharge (APAGD) was carried out simply with a transformer of 1 : 500 driven by a alternating current with a frequency of 50 Hz. Typical stable discharge parameters, namely voltage of 400 V to 850 V and current of 60 mA to 110 mA were measured by oscillograph. Simulation of the discharge process suggested that the stable discharge was supported by the impedance from the secondary coil of the transformer, which offered a negative feedback to prevent the discharge from turning into an arc. An interpretation was given for the oscillogram of the sinuous discharge current and square voltage. Furthermore, the electron temperature and electron density averaged in the discharge channel of APAGD were estimated.展开更多
Abstract In the four-anode device, the mirror magnetic field affects the characteristics of charged particles motion, so that the current-voltage relations of glow discharge are changed. Firstly, the discharge device ...Abstract In the four-anode device, the mirror magnetic field affects the characteristics of charged particles motion, so that the current-voltage relations of glow discharge are changed. Firstly, the discharge device is introduced, and the distribution of mirror magnetic field generated by the loops surrounding the discharge chamber is presented. Both the discharge current-voltage characteristics and the radial distributions of electron density are measured, respectively, with/without the magnetic field. When the discharge occurs in a 99.99% helium with a pressure ranging from 100 Pa to 800 Pa without magnetic field, the voltage, sustaining a certain abnormal glow discharge current, decreases with the increase in gas pressure. With a mirror magnetic field of certain intensity, the discharge voltage increases with the current in a rate slower than that without the magnetic field. Moreover, when the magnetic field intensity increases, the discharge voltage first decreases then increases. Simultaneously, the mirror magnetic field affects the moving characteristics of charged particles, and causes a more inhomogeneous electron density.展开更多
Background: Vaginal discharge is one of the most common troubles faced by childbearing age women. About 20% - 25% of women who visit service of gynecology complain of vaginal discharge and leucorrhoea. Management of v...Background: Vaginal discharge is one of the most common troubles faced by childbearing age women. About 20% - 25% of women who visit service of gynecology complain of vaginal discharge and leucorrhoea. Management of vaginal discharge in low-income countries generally depends on syndromic approach, which limits the understanding of specific responsible agents. Thus targeted management is based on the identification of causal organism and targeting of therapy against it, while syndromic management is based on presence of high risk factors. Thus the oral combination kit (Azimyn FS Kit®) offers convenience of a one-day treatment compared to other multidose treatments, which will also ensure high patient adherence to treatment, thus increasing chances of desired results. Due to its widespread use, it is proposed to evaluate the effectiveness of this oral association kit therapy in management of vaginal discharge in the population of our milieu in the Democratic Republic of Congo (DRC) particularly those received in outpatient consultation in some medical facilities in city of Kinshasa. Expensive laboratory tests and the associated waiting period for result mean that patient remains without treatment while waiting for test results. Therefore, by adopting a syndromic management approach, patient’s eligibility for treatment will be decided based on abnormal vaginal discharge, their characteristics, severity and other presentations symptomatic. This approach will also avoid losing sight of patients during follow-up and will help to reduce financial burden for patients. Objectives: To determine the efficacy and safety of oral combination kit therapy containing secnidazole, azithromycin and fluconazole (Azimyn FS Kit®) in syndromic treatment of abnormal vaginal discharge in patients received in outpatient consultation in some medical facilities in the city of Kinshasa;to measure rate of recurrence of abnormal vaginal discharge in these patients. And to identify the adverse effects observed in these patients who received treatment with the combined oral kit containing secnidazole, azithromycin and fluconazole (Azimyn FS Kit®) in outpatient consultation in some medical facilities in the city of Kinshasa. Methods: It will be a cross-sectional descriptive study. Sample size will be 319 women of childbearing age who consult the gynecology department with complaint of abnormal vaginal discharge and suspicion of vaginal infection, who agree to abstain from sex during treatment and who have given their written consent to use their personal and/or health data in the study. Conclusion: A study on clinical efficacy of oral combination therapy based on secnidazole, azithromycin and fluconazole is beneficial.展开更多
Background: Vaginal discharge is one of most common and nagging problems that women face. About 20% - 25% of women who visit gynecology department complain of vaginal discharge and leucorrhoea. An orally administered ...Background: Vaginal discharge is one of most common and nagging problems that women face. About 20% - 25% of women who visit gynecology department complain of vaginal discharge and leucorrhoea. An orally administered combination kit, containing 2 g secnidazole, 1 g azithromycin and 150 mg fluconazole (Azimyn FS Kit), has been successfully evaluated in clinical trials and used in several countries for management syndromic vaginal discharge due to infections. Methods: This is a longitudinal study which aimed to verify the clinical efficacy of the combined oral kit containing secnidazole, azithromycin and fluconazole (Azimyn FS Kit<sup><sup>®</sup></sup>) in the syndromic treatment of abnormal vaginal discharge in patients received in outpatient consultations in Kinshasa/DR Congo from March to September 2023. Results: Majority of patients had whitish vaginal discharge (51.6%) of average abundance (56.2%), accompanied by pruritus in 72.1% of cases, and dyspareunia in 23.5% of cases and hypogastralgia in 40.2% of cases. One week after treatment with the Azimyn FS<sup><sup>®</sup></sup> combined kit, at the greatest majority of patients (97.3%), abnormal vaginal discharge had decreased by more than 50% (84.1%). Two weeks after treatment with the Azimyn FS<sup><sup>®</sup></sup> combined kit, almost all patients (97.3%) no longer had abnormal vaginal discharge which had completely disappeared. Conclusion: A single dose of secnidazole, azithromycin and fluconazole in the form of an oral combi-kit (Azimyn FS Kit) has shown excellent therapeutic effectiveness in the syndromic treatment of abnormal vaginal discharge wherein patients were treated without diagnostic confirmation.展开更多
基金National Natural Science Foundation of China (No. 10475060)
文摘Methane conversion to C2 hydrocarbons has been investigated with the addition of hydrogen in a plasma reactor of abnormal glow discharge at atmospheric pressure. The aim of this experiment is to minimize coke formation and improve discharge stability. The typical conditions in the experiment are 300 ml of total feed flux and 400 W of discharge power. The experimental results show that methane conversion is from 91.6% to 35.2% in mol, acetylene selectivity is from 90.2% to 57.6%, and ethylene selectivity is approximately from 7.8% to 3.6%, where the coke increases gradually along with the increase of CH4/H2 from 2 : 8 to 9 : 1. A stable discharge for a considerable running time can be obtained only at a lower ratio of CH4/H2 = 2:8 or 3: 7. These phenomena indicate that the coke deposition during methane conversion is obviously reduced by adding a large amount of hydrogen during an abnormal glow discharge. A qualitative interpretation is presented, namely, with abundant hydrogen, the possibility that hydrogen molecules are activated to hydrogen radicals is increased with the help of the abnormal glow discharge. These hydrogen radicals react with carbon radicals to form C2 hydrocarbon products. Therefore, the deposition of coke is restrained.
基金Supported by the National Natural Science Foundation of China under Grant No 51677190the Hunan Provincial Natural Science Foundation of China under Grant No 2017JJ1005
文摘Propylene carbonate (PC) has a great potential to be used as an energy storage medium in the compact pulsed power sources due to its high dielectric constant and large resistivity. We investigate both the positive and negative breakdown characteristics of PC. The streamer patterns are obtained by ultra-high-speed cameras. The experimental results show that the positive breakdown voltage of PC is about 135% higher than the negative one, which is abnormal compared with the common liquid. The shape of the positive streamer is filamentary and branchy, while the negative streamer is tree-like and less branched. According to these experimental results, a charge layer structure model at the interface between the metal electrode and liquid is presented. It is suggested that the abnormal polarity effect basically arises from the electric field strength difference in the interface between both electrodes and PC. What is more, the recombination radiation and photoionization also play an important role in the whole discharge process.
基金National Natural Science Foundation of China(No.10475060)
文摘Atmospheric pressure abnormal glow discharge (APAGD) was carried out simply with a transformer of 1 : 500 driven by a alternating current with a frequency of 50 Hz. Typical stable discharge parameters, namely voltage of 400 V to 850 V and current of 60 mA to 110 mA were measured by oscillograph. Simulation of the discharge process suggested that the stable discharge was supported by the impedance from the secondary coil of the transformer, which offered a negative feedback to prevent the discharge from turning into an arc. An interpretation was given for the oscillogram of the sinuous discharge current and square voltage. Furthermore, the electron temperature and electron density averaged in the discharge channel of APAGD were estimated.
基金Program for New Century Excellent Talents in University (NCET) of ChinaFundation of the Key Lab of Infrared and Low Temperature Plasma of Anhui Province of China(No.2007A003003U)
文摘Abstract In the four-anode device, the mirror magnetic field affects the characteristics of charged particles motion, so that the current-voltage relations of glow discharge are changed. Firstly, the discharge device is introduced, and the distribution of mirror magnetic field generated by the loops surrounding the discharge chamber is presented. Both the discharge current-voltage characteristics and the radial distributions of electron density are measured, respectively, with/without the magnetic field. When the discharge occurs in a 99.99% helium with a pressure ranging from 100 Pa to 800 Pa without magnetic field, the voltage, sustaining a certain abnormal glow discharge current, decreases with the increase in gas pressure. With a mirror magnetic field of certain intensity, the discharge voltage increases with the current in a rate slower than that without the magnetic field. Moreover, when the magnetic field intensity increases, the discharge voltage first decreases then increases. Simultaneously, the mirror magnetic field affects the moving characteristics of charged particles, and causes a more inhomogeneous electron density.
文摘Background: Vaginal discharge is one of the most common troubles faced by childbearing age women. About 20% - 25% of women who visit service of gynecology complain of vaginal discharge and leucorrhoea. Management of vaginal discharge in low-income countries generally depends on syndromic approach, which limits the understanding of specific responsible agents. Thus targeted management is based on the identification of causal organism and targeting of therapy against it, while syndromic management is based on presence of high risk factors. Thus the oral combination kit (Azimyn FS Kit®) offers convenience of a one-day treatment compared to other multidose treatments, which will also ensure high patient adherence to treatment, thus increasing chances of desired results. Due to its widespread use, it is proposed to evaluate the effectiveness of this oral association kit therapy in management of vaginal discharge in the population of our milieu in the Democratic Republic of Congo (DRC) particularly those received in outpatient consultation in some medical facilities in city of Kinshasa. Expensive laboratory tests and the associated waiting period for result mean that patient remains without treatment while waiting for test results. Therefore, by adopting a syndromic management approach, patient’s eligibility for treatment will be decided based on abnormal vaginal discharge, their characteristics, severity and other presentations symptomatic. This approach will also avoid losing sight of patients during follow-up and will help to reduce financial burden for patients. Objectives: To determine the efficacy and safety of oral combination kit therapy containing secnidazole, azithromycin and fluconazole (Azimyn FS Kit®) in syndromic treatment of abnormal vaginal discharge in patients received in outpatient consultation in some medical facilities in the city of Kinshasa;to measure rate of recurrence of abnormal vaginal discharge in these patients. And to identify the adverse effects observed in these patients who received treatment with the combined oral kit containing secnidazole, azithromycin and fluconazole (Azimyn FS Kit®) in outpatient consultation in some medical facilities in the city of Kinshasa. Methods: It will be a cross-sectional descriptive study. Sample size will be 319 women of childbearing age who consult the gynecology department with complaint of abnormal vaginal discharge and suspicion of vaginal infection, who agree to abstain from sex during treatment and who have given their written consent to use their personal and/or health data in the study. Conclusion: A study on clinical efficacy of oral combination therapy based on secnidazole, azithromycin and fluconazole is beneficial.
文摘Background: Vaginal discharge is one of most common and nagging problems that women face. About 20% - 25% of women who visit gynecology department complain of vaginal discharge and leucorrhoea. An orally administered combination kit, containing 2 g secnidazole, 1 g azithromycin and 150 mg fluconazole (Azimyn FS Kit), has been successfully evaluated in clinical trials and used in several countries for management syndromic vaginal discharge due to infections. Methods: This is a longitudinal study which aimed to verify the clinical efficacy of the combined oral kit containing secnidazole, azithromycin and fluconazole (Azimyn FS Kit<sup><sup>®</sup></sup>) in the syndromic treatment of abnormal vaginal discharge in patients received in outpatient consultations in Kinshasa/DR Congo from March to September 2023. Results: Majority of patients had whitish vaginal discharge (51.6%) of average abundance (56.2%), accompanied by pruritus in 72.1% of cases, and dyspareunia in 23.5% of cases and hypogastralgia in 40.2% of cases. One week after treatment with the Azimyn FS<sup><sup>®</sup></sup> combined kit, at the greatest majority of patients (97.3%), abnormal vaginal discharge had decreased by more than 50% (84.1%). Two weeks after treatment with the Azimyn FS<sup><sup>®</sup></sup> combined kit, almost all patients (97.3%) no longer had abnormal vaginal discharge which had completely disappeared. Conclusion: A single dose of secnidazole, azithromycin and fluconazole in the form of an oral combi-kit (Azimyn FS Kit) has shown excellent therapeutic effectiveness in the syndromic treatment of abnormal vaginal discharge wherein patients were treated without diagnostic confirmation.