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Application of a new daytime surgery and same-day discharge mode in cataract clinic
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作者 Liqi Huang Xia Xiao Sufen Lu 《Annals of Eye Science》 2021年第1期28-32,共5页
Background:This study aims to investigate the application and effect of a new daytime surgery and same-day discharge mode in cataract clinic.Methods:Two hundred patients with cataract intended to undertake daytime sur... Background:This study aims to investigate the application and effect of a new daytime surgery and same-day discharge mode in cataract clinic.Methods:Two hundred patients with cataract intended to undertake daytime surgery from August 2019 to January 2020 in the Cataract department were enrolled for the study.Among them,100 patients from January 2020 with the new daytime surgery and same-day discharge were the experimental group.While the other 100 patients without the designated set-up from August 2019 worked as a control group.The length and cost of hospitalization,the length of waiting for the elevator,the patient satisfaction,and the awareness rate of health education were evaluated.Results:After application of the new daytime surgery and same-day discharge set-up,the patients’satisfaction rate increased from 91%to 95%,and the rate of awareness of health education increased from 87%to 90%,the difference was statistically significant(χ^(2)=0.61,P=0.04 andχ^(2)=0.22,P=0.01).The length of hospitalization,hospitalization costs and waiting time for elevators were much reduced than those without this set-up.Conclusions:The application of the cataract daytime surgery and same-day discharge set-up can effectively alleviate the overcrowding of the ward environment,reduce the workload of medical staff,and improve patient satisfaction.Therefore,the daytime surgery and same-day discharge set-up has wide clinical applications. 展开更多
关键词 CATARACT daytime surgery same-day discharge
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Feasibility of same-day discharge following endoscopic submucosal dissection for esophageal or gastric early cancer 被引量:2
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作者 Jing Wang Shi-Jie Li +6 位作者 Yan Yan Peng Yuan Wei-Feng Li Chang-Qi Cao Wei-Gang Chen Ke-Neng Chen QiWu 《World Journal of Gastroenterology》 SCIE CAS 2022年第41期5957-5967,共11页
BACKGROUND Endoscopic submucosal dissection(ESD)is an established technique for the treatment of early gastrointestinal neoplasia.Generally,multi-day(M-D)admission is required for patients undergoing ESD due to potent... BACKGROUND Endoscopic submucosal dissection(ESD)is an established technique for the treatment of early gastrointestinal neoplasia.Generally,multi-day(M-D)admission is required for patients undergoing ESD due to potential complications.AIM To evaluate the feasibility of a same-day(S-D)discharge strategy for ESD of the esophagus or stomach.METHODS The data of patients who underwent esophageal or gastric ESD were retrospectively collected from January 2018 to December 2021 at Peking University Cancer Hospital.The propensity score matching(PSM)method was applied to balance the unevenly distributed patient baseline characteristics between the S-D and M-D groups.Intraoperative and postoperative parameters were compared between the matched groups.RESULTS Among the 479 patients reviewed,470 patients,including 91 in the S-D group and 379 in the M-D group,fulfilled the inclusion and exclusion criteria.Following PSM,78 patients in each group were paired using the 1:1 nearest available score match algorithm.No significant difference was found between groups with respect to intraoperative and postprocedural major adverse events(AEs).Tumor size,complete resection rate,and procedural duration were comparable between the groups.The S-D group demonstrated a significantly shorter length of hospital stay(P<0.001)and lower overall medical expenses(P<0.001)compared with the M-D group.CONCLUSION The S-D discharge strategy may be feasible and effective for esophagogastric ESD,and the procedural-related AEs can be managed successfully. 展开更多
关键词 Endoscopic submucosal dissection Early esophageal cancer Early gastric cancer same-day surgery Adverse event
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The Current State of Transradial Access:A Perspective on Transradial Outcomes,Learning Curves,and Same-Day Discharge
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作者 Jennifer A.Rymer Sunil V.Rao 《Cardiovascular Innovations and Applications》 2018年第B07期149-162,共14页
The adoption of transradial access in the United States and internationally has been growing over the past few years.In the population of patients presenting with acute coronary syndromes,particularly ST-elevation myo... The adoption of transradial access in the United States and internationally has been growing over the past few years.In the population of patients presenting with acute coronary syndromes,particularly ST-elevation myocardial infarction,transradial access has the benefit of fewer vascular and bleeding complications and lower mortality rates over transfemoral access.We will examine the current evidence supporting transradial access for several patient populations,including those patients presenting with acute coronary syndromes.We will review the literature regarding the learning curve for transradial access with new operators,as well as experienced transfemoral operators new to transradial access.Finally,we will investigate the role of transradial access in same-day discharge for stable patients undergoing percutaneous coronary intervention. 展开更多
关键词 TRANSRADIAL PERCUTANEOUS coronary intervention learning curves OUTCOMES same-day discharge
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Sustainable nitrogen fixation by bubble discharge plasma:Performance optimization and mechanism
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作者 Yuankun Ye Xiaoyang Wei +2 位作者 Li Zhang Sen Wang Zhi Fang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第11期692-701,共10页
Sustainable nitrogen fixation driven by renewable energy sources under mild conditions has been widely sought to replace the industrial Haber-Bosch process.The fixation of nitrogen in the form of NO_(x)^(-)and NH_4^(+... Sustainable nitrogen fixation driven by renewable energy sources under mild conditions has been widely sought to replace the industrial Haber-Bosch process.The fixation of nitrogen in the form of NO_(x)^(-)and NH_4^(+)into aqueous solutions using electricity-driven gas-liquid discharge plasma is considered a promising prescription.In this paper,a scalable bubble discharge excited by nanosecond pulse power is employed for nitrogen fixation in the liquid phase.The nitrogen fixation performance and the mechanisms are analyzed by varying the power supply parameters,working gas flow rate and composition.The results show that an increase in voltage and frequency can result in an enhanced NO_(3)^(-)yield.Increases in the gas flow rate can result in inadequate activation of the working gas,which together with more inefficient mass transfer efficiencies can reduce the yield.The addition of O_(2) effectively elevates NO_(3)^(-)production while simultaneously inhibiting NH_4^(+) production.The addition of H_(2)O vapor increases the production of OH and H,thereby promoting the generation of reactive nitrogen and enhancing the yield of nitrogen fixation.However,the excessive addition of O_(2) and H_(2)O vapor results in negative effect on the yield of nitrogen fixation,due to the significant weakening of the discharge intensity.The optimal nitrogen fixation yield was up to 16.5 μmol/min,while the optimal energy consumption was approximately 21.3 MJ/mol in this study.Finally,the mechanism related to nitrogen fixation is discussed through the optical emission spectral(OES) information in conjunction with the simulation of energy loss paths in the plasma by BOLSIG+.The work advances knowledge of the effect of parameter variations on nitrogen fixation by gas-liquid discharge for higher yield and energy production. 展开更多
关键词 Nitrogen fixation Gas-liquid discharge plasma Bubble discharge MECHANISM
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Comparative analysis of single-crater parameters in ultrasonic-assisted and unassisted micro-EDM of Ti6Al4V using discharge plasma imaging
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作者 Sohaib Raza Chandrakant Nirala 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2024年第2期11-24,共14页
Ultrasonic-assisted micro-electro-discharge machining(EDM)has the potential to enhance processing responses such as material removal rate(MRR)and surface finish.To understand the reasons for this enhancement,the physi... Ultrasonic-assisted micro-electro-discharge machining(EDM)has the potential to enhance processing responses such as material removal rate(MRR)and surface finish.To understand the reasons for this enhancement,the physical mechanisms responsible for the individual discharges and the craters that they form need to be explored.This work examines features of craters formed by single discharges at various parameter values in both conventional and ultrasonic-assistedEDM of Ti6Al4V.High-speed imaging of the plasma channel is performed,and data on the individual discharges are captured in real-time.A 2D axisymmetric model using finite element software is established to model crater formation.On the basis of simulation and experimental results,a comparative study is then carried out to examine the effects of ultrasonic vibrational assistance on crater geometry.For every set ofEDM parameters,the crater diameter and depth from a single discharge are found to be higher in ultrasonic-assistedEDM than in conventionalEDM.The improved crater geometry and the reduced bulge formation at the crater edges are attributed to the increased melt pool velocity and temperature predicted by the model. 展开更多
关键词 Ultrasonic vibration discharge crater Plasma diameter Single discharge
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Effect of dielectric material on the uniformity of nanosecond pulsed dielectric barrier discharge
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作者 Wenhao ZHOU Dongxuan ZHANG +3 位作者 Xiaohui DUAN Xi ZHU Feng LIU Zhi FANG 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第9期79-87,共9页
Dielectric barrier discharge(DBD)is considered as a promising technique to produce large volume uniform plasma at atmospheric pressure,and the dielectric barrier layer between the electrodes plays a key role in the DB... Dielectric barrier discharge(DBD)is considered as a promising technique to produce large volume uniform plasma at atmospheric pressure,and the dielectric barrier layer between the electrodes plays a key role in the DBD processes and enhancing discharge uniformity.In this work,the uniformity and discharge characteristics of the nanosecond(ns)pulsed DBD with dielectric barrier layers made of alumina,quartz glass,polycarbonate(PC),and polypropylene(PP)are investigated via discharge image observation,voltage-current waveform measurement and optical emission spectral diagnosis.Through analyzing discharge image by gray value standard deviation method,the discharge uniformity is quantitatively calculated.The effects of the space electric field intensity,the electron density(Ne),and the space reactive species on the uniformity are studied with quantifying the gap voltage Ug and the discharge current Ig,analyzing the recorded optical emission spectra,and simulating the temporal distribution of Ne with a one-dimensional fluid model.It is found that as the relative permittivity of the dielectric materials increases,the space electric field intensity is enhanced,which results in a higher Ne and electron temperature(Te).Therefore,an appropriate value of space electric field intensity can promote electron avalanches,resulting in uniform and stable plasma by the merging of electron avalanches.However,an excessive value of space electric field intensity leads to the aggregation of space charges and the distortion of the space electric field,which reduce the discharge uniformity.The surface roughness and the surface charge decay are measured to explain the influences of the surface properties and the second electron emission on the discharge uniformity.The results in this work give a comprehensive understanding of the effect of the dielectric materials on the DBD uniformity,and contribute to the selection of dielectric materials for DBD reactor and the realization of atmospheric pressure uniform,stable,and reactive plasma sources. 展开更多
关键词 dielectric barrier discharge dielectric material UNIFORMITY discharge characteristics
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On the evolution and formation of discharge morphology in pulsed dielectric barrier discharge
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作者 陈星宇 李孟琦 +3 位作者 王威逸 张权治 彭涛 熊紫兰 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第4期101-113,共13页
The discharge morphology of pulsed dielectric barrier discharge(PDBD) plays important roles in its applications. Here, we systematically investigated the effects of the voltage amplitude,discharge gap, and O_(2)conten... The discharge morphology of pulsed dielectric barrier discharge(PDBD) plays important roles in its applications. Here, we systematically investigated the effects of the voltage amplitude,discharge gap, and O_(2)content on the PDBD morphology, and revealed the possible underlying mechanism of the U-shaped formation. First, the morphological evolution under different conditions was recorded. A unique U-shaped region appears in the middle edge region when the gap is larger than 2 mm, while the entire discharge region remains columnar under a 2 mm gap in He PDBD. The width of the discharge and the U-shaped region increase with the increase in voltage, and decrease with the increase of the gap and O_(2)content. To explain this phenomenon,a two-dimensional symmetric model was developed to simulate the spatiotemporal evolution of different species and calculate the electric thrust. The discharge morphology evolution directly corresponds to the excited-state atomic reduction process. The electric thrust on the charged particles mainly determines the reaction region and strongly influences the U-shaped formation.When the gap is less than 2 mm, the electric thrust is homogeneous throughout the entire region,resulting in a columnar shape. However, when the gap is larger than 2 mm or O_(2)is added, the electric thrust in the edge region becomes greater than that in the middle, leading to the U-shaped formation. Furthermore, in He PDBD, the charged particles generating electric thrust are mainly electrons and helium ions, while in He/O_(2)PDBD those that generate electric thrust at the outer edge of the electrode surface are mainly various oxygen-containing ions. 展开更多
关键词 low-temperature plasma dielectric barrier discharge discharge morphology particle distribution electric thrust
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Predictors of Abnormal Vaginal Discharge among Women of Reproductive Age in Southeast Nigeria
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作者 Jideuma Egwim Victor Dike +5 位作者 Hope Igbonagwam Nkechinyere Oke Uzoma Amajo Akuchi Okafor Angela Izegbune Ijedimma Okafor 《International Journal of Clinical Medicine》 CAS 2024年第7期240-256,共17页
Background: An abnormal vaginal discharge is a common complaint among women of reproductive age, and it can indicate serious conditions like pelvic inflammatory disease and cervical cancer. This study aimed to assess ... Background: An abnormal vaginal discharge is a common complaint among women of reproductive age, and it can indicate serious conditions like pelvic inflammatory disease and cervical cancer. This study aimed to assess the predictors of abnormal vaginal discharge in women of reproductive age group in Imo State, Southeast Nigeria. Methods: A cross-sectional study was conducted among 368 women of reproductive age group attending the clinic at Federal University Teaching Hospital Owerri, in Imo State, Nigeria. Respondents were recruited using a systematic sampling technique. Data were collected using a pre-tested interviewer-administered questionnaire. Multivariable analysis was performed to determine predictors of abnormal vaginal discharge. Statistical significance was set at p Results: The mean age of the respondents was 30 ±  4.5 years. Predictors of abnormal vaginal discharge were: age 36 - 45 years (OR: 4.5;95% C.I: 1.023 - 8.967, p = 0.041), being a student (OR: 2.4: 95% C.I: 1.496 - 7.336, p = 0.003), use of oral contraceptives (OR: 3.4;95% C.I: 1.068 - 6.932, p = 0.010), use of water cistern (OR: 4.7;C.I: 1.654 - 5.210, p = 0.028) anal hygiene practices (OR: 2.7;95% C.I: 1.142 - 4.809, p Conclusion: These findings suggest that targeted sexual and reproductive health interventions should be provided to reduce the risk of abnormal vaginal discharge in women of reproductive age group. 展开更多
关键词 PREDICTORS ABNORMAL VAGINAL discharge
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Discharge and mass transfer characteristics of atmospheric pressure gas-solid two-phase gliding arc
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作者 Min ZHU Yuchen PING +2 位作者 Yinghao ZHANG Chaohai ZHANG Shuqun WU 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第9期88-96,共9页
In this work,a gas-solid two-phase gliding arc discharge(GS-GAD)reactor was built.Gliding arc was formed in the gap between the blade electrodes,and solid powder was deposited on the sieve plate positioned beneath the... In this work,a gas-solid two-phase gliding arc discharge(GS-GAD)reactor was built.Gliding arc was formed in the gap between the blade electrodes,and solid powder was deposited on the sieve plate positioned beneath the blade electrodes.A range of experimental parameters,including the inter-electrode spacing,gas flow rate,applied voltage,and the type of the powder,were systematically varied to elucidate the influence of solid powder matter on the dynamics of gliding arc discharge(GAD).The discharge images were captured by ICCD and digital camera to investigate the mass transfer characteristics of GS-GAD,and the electrical parameters,such as the effective values of voltage,current,and discharge power were record to reveal the discharge characteristics of GS-GAD.The results demonstrate that powder undergoes spontaneous movement towards the upper region of the gliding arc due to the influence of electric field force.Increasing the discharge voltage,decreasing relative dielectric constant of the powder and reducing the electrode-to-sieve-plate distance all contribute to a greater involvement of powder in the GAD process,subsequently resulting in an enhanced powder concentration within the GAD region.Additionally,powder located beneath the gliding arc experiences downward resistance caused by the opposing gas flow and arc.Excessive gas flow rate notably hampers the powder concentration within the discharge region,and the velocity of powder motion in the upper part of the GAD region is reduced.Under the condition of electrode-to-sieve-plate distance of 30 mm,gas flow rate of 1.5 L/min,and peak-to-peak voltage of 31 kV,the best combination of arc gliding and powder spark discharge phenomena can be achieved with the addition of Al_(2)O_(3) powder. 展开更多
关键词 gliding arc discharge atmospheric pressure plasma multiphase discharge mass transfer
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Novel method for identifying the stages of discharge underwater based on impedance change characteristic
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作者 高崇 康忠健 +3 位作者 龚大建 张扬 王玉芳 孙一鸣 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第4期133-145,共13页
It is difficult to determine the discharge stages in a fixed time of repetitive discharge underwater due to the arc formation process being susceptible to external environmental influences. This paper proposes a novel... It is difficult to determine the discharge stages in a fixed time of repetitive discharge underwater due to the arc formation process being susceptible to external environmental influences. This paper proposes a novel underwater discharge stage identification method based on the Strong Tracking Filter(STF) and impedance change characteristics. The time-varying equivalent circuit model of the discharge underwater is established based on the plasma theory analysis of the impedance change characteristics and mechanism of the discharge process. The STF is used to reduce the randomness of the impedance of repeated discharges underwater, and then the universal identification resistance data is obtained. Based on the resistance variation characteristics of the discriminating resistance of the pre-breakdown, main, and oscillatory discharge stages, the threshold values for determining the discharge stage are obtained. These include the threshold values for the resistance variation rate(K) and the moment(t).Experimental and error analysis results demonstrate the efficacy of this innovative method in discharge stage determination, with a maximum mean square deviation of Scrless than 1.761. 展开更多
关键词 discharge underwater discharge stage identification impedance characteristics strong tracking filter
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Experimental study on the effect of H_(2)O and O_(2) on the degradation of SF_(6) by pulsed dielectric barrier discharge
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作者 李亚龙 万昆 +5 位作者 王宇非 张晓星 杨照迪 傅明利 卓然 王邸博 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第2期125-131,共7页
SF_(6) has excellent insulation performance and arc extinguishing ability,and is widely used in the power industry.However,its global warming potential is about 23,500 times that of C0_(2),it can exist stably in the a... SF_(6) has excellent insulation performance and arc extinguishing ability,and is widely used in the power industry.However,its global warming potential is about 23,500 times that of C0_(2),it can exist stably in the atmosphere,it is not easily degradable and is of great potential harm to the environment.Based on pulsed dielectric barrier discharge plasma technology,the effects of H_(2)O and 0_(2) on the degradation of SF_(6) were studied.Studies have shown that H_(2)O can effectively promote the decomposition of SF_(6) and improve its degradation rate and energy efficiency of degradation.Under the action of a pulse input voltage and input frequency of 15 kV and 15 kHz,respectively,when H_(2)O is added alone the effect of 1% H_(2)O is the best,and the rate and energy efficiency of degradation of SF_(6) reach their maximum values,which are 91.9% and 8.25 g kWh^(-1),respectively.The synergistic effect of H_(2)O and O_(2) on the degradation of SF_(6) was similar to that of H_(2)O.When the concentration of H_(2)O and O_(2) was 1%,the system obtained the best rate and energy efficiency of degradation,namely 89.7% and 8.05 g kWh~(-1),respectively.At the same time,different external gases exhibit different capabilities to regulate decomposition products.The addition of H_(2)O can effectively improve the selectivity of S0_(2).Under the synergistic effect of H_(2)O and O_(2),with increase in O_(2) concentration the degradation products gradually transformed into SO_(2)F_(2).From the perspective of harmless treatment of the degradation products of SF_(6),the addition of O_(2) during the SF_(6) degradation process should be avoided. 展开更多
关键词 SF_(6) pulsed dielectric barrier discharge DEGRADATION discharge gas
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Progress in the creation of long-lived atmospheric luminous formations in a pulsed electric discharge with an electrolytic electrode
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作者 Jingfeng YAO Jianfei LI +6 位作者 Shixin ZHAO Chengxun YUAN Lin MIAO Nie CHEN A.M.ASTAFIEV A.A.KUDRYAVTSEV G.D.SHABANOV 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第12期82-88,共7页
This work presents an analysis of the research conducted in many countries in recent years on the so-called Gatchina discharge.The findings indicate that the Gatchina discharge exhibits the majority of the characteris... This work presents an analysis of the research conducted in many countries in recent years on the so-called Gatchina discharge.The findings indicate that the Gatchina discharge exhibits the majority of the characteristics of natural ball lightning,making it the most effective method for reproducing and studying this phenomenon.To a large extent,our new results are based on experiments performed for the first time to visualize dust particles arising in an erosive emission,as well as the formation of vortex flows.These experiments make it possible to explain the ability of the Gatchina discharge to maintain its shape for a long time in the afterglow. 展开更多
关键词 Gatchina discharge ball lightning SELF-ORGANIZATION dusty plasma
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Experimental study of the effect of gas discharge on ionic liquid electrospray
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作者 石文 杨鹏飞 +1 位作者 宋培义 吴健 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第4期37-43,共7页
Ionic liquid electrospray(ILE) in an atmospheric environment is often accompanied by the gas discharge phenomenon. It interferes with the normal operation of the electrospray and the measurement of experimental parame... Ionic liquid electrospray(ILE) in an atmospheric environment is often accompanied by the gas discharge phenomenon. It interferes with the normal operation of the electrospray and the measurement of experimental parameters. In this study, electrospray experiments were conducted on the ionic liquid EMI-BF4. The observations revealed that the operating modes of the ionic liquid depend on the voltage polarity at high voltages. Additionally, a correspondence between the operating mode of ILE and the current signal in the circuit was established. The shape of the liquid cone formed at the needle tip bore a striking resemblance to the plume of corona discharge, suggesting that the motion trajectory of electrons influenced the curvature of the liquid cone. Steamer theory provided a clear explanation for the change in curvature as the voltage increased. 展开更多
关键词 ionic liquid ELECTROSPRAY Taylor cone jet corona discharge
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Role of micro-Ca/In alloying in tailoring the microstructural characteristics and discharge performance of dilute Mg-Bi-Sn-based alloys as anodes for Mg-air batteries
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作者 Fei-er Shangguan Wei-li Cheng +6 位作者 Yu-hang Chen Ze-qin Cui Hui Yu Hong-xia Wang Li-fei Wang Hang Li Hua Hou 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第1期251-266,共16页
The influence of micro-Ca/In alloying on the microstructural charac teristics,electrochemical behaviors and discharge properties of extruded dilute Mg-0.5Bi-0.5Sn-based(wt.%)alloys as anodes for Mg-air batteries are e... The influence of micro-Ca/In alloying on the microstructural charac teristics,electrochemical behaviors and discharge properties of extruded dilute Mg-0.5Bi-0.5Sn-based(wt.%)alloys as anodes for Mg-air batteries are evaluated.The grain size and texture intensity of the Mg-Bi-Sn-based alloys are significantly decreased after the Ca/In alloying,particularly for the In-containing alloy.Note that,in addition to nanoscale Mg_(3)Bi_(2)phase,a new microscale Mg_(2)Bi_(2)Ca phase forms in the Ca-containing alloy.The electrochemical test results demonstrate that Ca/In micro-alloying can enhance the electrochemical activity.Using In to alloy the Mg-Bi-Sn-based alloy is effective in restricting the cathodic hydrogen evolution(CHE)kinetics,leading to a low self-corrosion rate,while severe CHE occurred after Ca alloying.The micro-alloying of Ca/In to Mg-Bi-Sn-based alloy strongly deteriorates the compactness of discharge products film and mitigates the"chunk effect"(CE),hence the cell voltage,anodic efficiency as well as discharge capacity are greatly improved.The In-containing alloy exhibits outstanding discharge performance under the combined effect of the modified microstructure and discharge products,thus making it a potential anode material for primary Mg-air battery. 展开更多
关键词 Mg-air batteries Mg-Bi-Sn based alloys Electrochemical behaviors discharge properties
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Discharge evolution law of debris flow based on a sharp bend physical modeling test
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作者 LU Ming SUN Hao +3 位作者 LIU Jinfeng Abrar HUSSAIN SHANG Yuqi FU Hang 《Journal of Mountain Science》 SCIE CSCD 2024年第6期1904-1915,共12页
For the basins with debris flow development,its channel terrain exhibits a tortuous shape,which significantly restricts the movement of debris flows and leads to severe erosion effects on the concave bank.Therefore,th... For the basins with debris flow development,its channel terrain exhibits a tortuous shape,which significantly restricts the movement of debris flows and leads to severe erosion effects on the concave bank.Therefore,this study aims to analyze the shear force of debris flows within the bend channel.We established the relationship between the shear force and bend curvature through laboratory experiments.Under the long-term erosion by debris flows,the curvature radius of bends gradually increases,however,when this increasing trend reaches an equilibrium state with the intensity of debris flow discharge,there will be no significant change in curvature radius.In general,the activity pattern and discharges of debris flows would remain relatively stable.Hence,we can infer the magnitude of debris flow discharges from the terrain parameters of the bend channel. 展开更多
关键词 Debris flow discharge Erosion effect Bend channel Curvature radius
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Performance of pulsed plasma thruster at low discharge energy
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作者 李鸿俊 林泽豪 +3 位作者 胡浩俊 吴文东 陈爱虹 杜德扬 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第4期122-132,共11页
As the size of satellites scales down, low-power and compact propulsion systems such as the pulsed plasma thruster(PPT) are needed for stabilizing these miniature satellites in orbit. Most PPT systems are operated at ... As the size of satellites scales down, low-power and compact propulsion systems such as the pulsed plasma thruster(PPT) are needed for stabilizing these miniature satellites in orbit. Most PPT systems are operated at 2 J or more of discharge energy. In this work, the performance of a PPT with a side-fed, tongue-flared electrode configuration operated within a lower discharge energy range of 0.5-2.5 J has been investigated. Ablation and charring of the polytetrafluoroethylene propellant surface were analyzed through field-effect scanning electron microscopy imaging and energy-dispersive X-ray spectroscopy. When the discharge energy fell below 2 J, inconsistencies occurred in the specific impulse and the thrust efficiency due to the measurement of the low mass bit. At energy ≥2 J, the performance parameters are compared with other PPT systems of similar configuration and discussed in depth. 展开更多
关键词 pulsed plasma thruster low discharge energy performance parameters
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Reconfigurable(4, 6^(2)) and(4, 8^(2)) Archimedean plasma photonic crystals in dielectric barrier discharge
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作者 李蕊 王启晗 +5 位作者 刘富成 高匡雅 侯笑含 贾萌萌 李庆 范伟丽 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第6期70-78,共9页
Archimedean photonic crystal has become a research area of great interest due to its various unique properties. Here, we experimentally demonstrate the realization of reconfigurable(4, 6^(2))and(4, 8^(2)) Archimedean ... Archimedean photonic crystal has become a research area of great interest due to its various unique properties. Here, we experimentally demonstrate the realization of reconfigurable(4, 6^(2))and(4, 8^(2)) Archimedean plasma photonic crystals(APPCs) by use of dielectric barrier discharges in air. Dynamical control on both the macrostructures including the lattice symmetry and the crystal orientation, and the microstructures including the fine structures of scattering elements has been achieved. The formation mechanisms of APPCs are studied by time-resolved measurements together with numerical simulations. Large omnidirectional band gaps of APPCs have been obtained. The tunable topology of APPCs may offer new opportunities for fabricating multi-functional and highly-integrated microwave devices. 展开更多
关键词 Archimedean lattice plasma photonic crystals dielectric barrier discharge
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Suppression of current-induced membrane discharge of bipolar membranes by regulating ion crossover transport
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作者 Tingting Yu Haolan Tao +2 位作者 Jingkun Li Cheng Lian Honglai Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期387-395,共9页
Bipolar membranes(BPMs)exhibit the unique capability to regulate the operating environment of electrochemical system through the water dissociation-combination processes.However,the industrial utilization of BPMs is l... Bipolar membranes(BPMs)exhibit the unique capability to regulate the operating environment of electrochemical system through the water dissociation-combination processes.However,the industrial utilization of BPMs is limited by instability and serious energy consumption.The current-induced membrane discharge(CIMD)at high-current conditions has a negative influence on the performance of anion-exchange membranes,but the underlying ion transport mechanisms in the BPMs remain unclear.Here,the CIMD-coupled Poisson-Nernst-Planck(PNP)equations are used to explore the ion transport mechanisms in the BPMs for both reverse bias and forward bias at neutral and acid-base conditions.It is demonstrated that the CIMD effect in the reverse-bias mode can be suppressed by enhancing the diffusive transport of salt counter-ions(Na^(+)and Cl^(−))into the BPMs,and that in the forward-bias mode with acid-base electrolytes can be suppressed by matching the transport rate of water counter-ions(H_(3)O^(+)and OH^(−)).Suppressing the CIMD can promote the water dissociation in the reverse-bias mode,as well as overcome the plateau of limiting current density and reduce the interfacial blockage of salt co-ions(Cl^(−))in the anion-exchange layer in the forward-bias mode with acid-base electrolytes.Our work highlights the importance of regulating ion crossover transport on improving the performance of BPMs. 展开更多
关键词 Bipolar membranes Current-induced membrane discharge Salt ion crossover Diffusion-migration-reaction process
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Discharge plasma for prebiotic chemistry: Pathways to life’s building blocks
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作者 DingWei Gan LongFei Hong +9 位作者 TianYu Li TianQi Zhang XiangYu Wang JiePing Fan RuSen Zhou DingXin Liu JianXi Ying Patrick JCullen YuFen Zhao RenWu Zhou 《Earth and Planetary Physics》 EI CAS CSCD 2024年第6期823-835,共13页
Discharge plasmas, recognized as unique platforms for investigating the origins of chemical life, have garnered extensive interest for their potential to simulate prebiotic conditions. This paper embarks on a comprehe... Discharge plasmas, recognized as unique platforms for investigating the origins of chemical life, have garnered extensive interest for their potential to simulate prebiotic conditions. This paper embarks on a comprehensive overview of recent advancements in the plasma-enabled synthesis of life’s building blocks, charting the complex environmental parameters believed to have surrounded life’s inception. This discussion elaborates on the fundamental mechanisms of discharge plasmas and their likely role in fostering conditions necessary for the origin of life on early Earth. We consider a variety of chemical reactions facilitated by plasma, specifically the synthesis of vital organic molecules - amino acids, nucleobases, sugars, and lipids. Further, we delve into the impact of plasmas on prebiotic chemical evolution. We expect this review to open new horizons for future investigations in plasma-related prebiotic chemistry that could offer valuable insights for unraveling the mysteries of life's origin. 展开更多
关键词 origin of life discharge plasma prebiotic chemistry chemical evolution
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Electron characteristics and dynamics in sub-millimeter pulsed atmospheric dielectric barrier discharge
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作者 方骏林 张亚容 +4 位作者 卢陈梓 顾莉莉 徐少锋 郭颖 石建军 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期496-502,共7页
The discharge characteristics and mechanism of sub-millimeter pulsed dielectric barrier discharge in atmosphericpressure helium are investigated experimentally and theoretically, demonstrating that when the discharge ... The discharge characteristics and mechanism of sub-millimeter pulsed dielectric barrier discharge in atmosphericpressure helium are investigated experimentally and theoretically, demonstrating that when the discharge gap distance is reduced from 1.00 mm to 0.20 mm, the discharge ignition time is reduced to approximately 40 ns and discharge intensity is enhanced in terms of the discharge optical emission intensity and density of the plasma species,(energetic electrons with energy above 8.40 e V). The simulated results show that as the discharge gap distance is further reduced to 0.10 mm,the number of energetic electrons decreases, which is attributable to the contraction of plasma bulk regime and reduction of electron density in the discharge bulk. Conversely, the proportion of energetic electrons to the total electrons in the discharge monotonically increases as the discharge gap distance is reduced from 1.00 mm to 0.10 mm. It is proposed that a gap distance of 0.12 mm is optimal to achieve a high concentration and proportion of energetic electrons in sub-millimeter pulsed atmosphere dielectric barrier discharge. 展开更多
关键词 sub-millimeter pulsed discharge plasma simulation electron dynamics and sheath
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