This study aims to revise the Belief in a Just World Scale(BJWS)for Chinese college students and test its reliability and validity(construct validity,convergent and divergent validity).Two samples of 546 and 595 colle...This study aims to revise the Belief in a Just World Scale(BJWS)for Chinese college students and test its reliability and validity(construct validity,convergent and divergent validity).Two samples of 546 and 595 college students were selected,respectively,using stratified cluster random sampling.Item analysis,exploratory factor analysis(EFA),confirmatory factor analysis(CFA),reliability analysis and convergent and divergent validity tests were carried out.The results showed that the 13 items of the BJWS have good item discrimination.The corrected item–total correlation in the general belief in a just world subscale was found to range from 0.464 to 0.655,and that in the personal belief in a just world subscale was 0.553 to 0.715.The internal consistency coefficients of the revised version of the BJWS and its subscales are good.The EFA and CFA results show that the structure and items of the revised scale are the same as those of the original scale.Belief in a just world was found to have significant positive correlations with gratitude and empathy,and has a significant negative correlation with anxiety,thereby exhibiting good convergent and divergent validity.Therefore,the Chinese revised version of the BJWS has good reliability and validity.展开更多
Lithium–sulfur batteries have been regarded as the most promising high-energy electrochemical energy storage device owing to the high energy density, low cost and environmental friendliness. However, traditional lith...Lithium–sulfur batteries have been regarded as the most promising high-energy electrochemical energy storage device owing to the high energy density, low cost and environmental friendliness. However, traditional lithium–sulfur batteries using ether-based electrolytes often suffer from severe safety risks(i.e. combustion). Herein, we demonstrated a novel kind of flame-retardant concentrated electrolyte(6.5 M lithium bis(trifluoromethylsulphonyl)imide/fluoroethylene carbonate) for highly-safe and widetemperature lithium–sulfur batteries. It was found that such concentrated electrolyte showed superior flame retardancy, high lithium-ion transference number(0.69) and steady lithium plating/stripping behavior(2.5 m Ah cm^(-2) over 3000 h). Moreover, lithium–sulfur batteries using this flame-retardant concentrated electrolyte delivered outstanding cycle performance in a wide range of temperatures(-10 °C, 25 °C and 90 °C). This superior battery performance is mainly attributed to the LiF-rich solid electrolyte interphase formed on lithium metal anode, which can effectively suppress the continuous growth of lithium dendrites. Above-mentioned fascinating characteristics would endow this flame-retardant concentrated electrolyte a very promising candidate for highly-safe and wide-temperature lithium–sulfur batteries.展开更多
BACKGROUND Suspension training(SET)is a method of neuromuscular training that enables the body to carry out active training under unstable support through a suspension therapy system.However,there have been few report...BACKGROUND Suspension training(SET)is a method of neuromuscular training that enables the body to carry out active training under unstable support through a suspension therapy system.However,there have been few reports in the literature on the application of SET to anterior cruciate ligament reconstruction(ACLR)patients.It is not clear what aspects of the patient's function are improved after SET.AIM To investigate the effect of SET on the neuromuscular function,postural control,and knee kinematics of patients after ACLR surgery.METHODS Forty participants were randomized to an SET group or a control group.The SET group subjects participated in a SET protocol over 6 wk.The control group subjects participated in a traditional training protocol over 6 wk.Isokinetic muscle strength of the quadriceps and hamstrings,static and dynamic posture stability test,and relative translation of the injured knee were assessed before and after training.RESULTS The relative peak torque of the quadriceps and hamstrings in both groups increased significantly(P<0.001),and the SET group increased by a higher percentage than those in the control group(quadriceps:P=0.004;hamstrings:P=0.011).After training,both groups showed significant improvements in static and dynamic posture stability(P<0.01),and the SET group had a greater change than the control group(P<0.05).No significant improvement on the relative translation of the injured knee was observed after training in either group(P>0.05).CONCLUSION Our findings show that SET promotes great responses in quadriceps and hamstring muscle strength and balance function in ACLR patients.展开更多
In this paper,we propose a neoteric and high-efficiency single image dehazing algorithm via contrast enhancement which is called STRASS(Spatio-Temporal Retinex-Inspired by an Averaging of Stochastic Samples)dehazing,i...In this paper,we propose a neoteric and high-efficiency single image dehazing algorithm via contrast enhancement which is called STRASS(Spatio-Temporal Retinex-Inspired by an Averaging of Stochastic Samples)dehazing,it is realized by constructing an efficient high-pass filter to process haze images and taking the influence of human vision system into account in image dehazing principles.The novel high-pass filter works by getting each pixel using RSR and computes the average of the samples.Then the low-pass filter resulting from the minimum envelope in STRESS framework has been replaced by the average of the samples.The final dehazed image is yielded after iterations of the high-pass filter.STRASS can be run directly without any machine learning.Extensive experimental results on datasets prove that STRASS surpass the state-of-the-arts.Image dehazing can be applied in the field of printing and packaging,our method is of great significance for image pre-processing before printing.展开更多
The oxygen plasma reactor based on dielectric barrier discharge principle can produce a high concentration of reactive oxygen species,which can cooperate with hydraulic cavitation gas-liquid mixer to realize the appli...The oxygen plasma reactor based on dielectric barrier discharge principle can produce a high concentration of reactive oxygen species,which can cooperate with hydraulic cavitation gas-liquid mixer to realize the application of advanced oxidation technology in water treatment.In this technology,the work pressure of the oxygen plasma reactor is decreased by the vacuum suction effect generated in the snap-back section of the gas-liquid mixed container.In this paper,the characteristics of single micro-discharge at different pressures were investigated with the methods of discharge image,electrical characteristics and spectral diagnosis,in order to analyze the electrical characteristics and reactive oxygen species generation efficiency of oxygen plasma reactor at the pressure range from 60 kPa to 100 kPa.The study indicated that,when the pressure decreases,the duty ratio of ionization in the discharge gap and number of electrons with high energy increases,leading to a rise in reactive oxygen species production.When the oxygen reaches the maximum ionization,the concentration of reactive oxygen species is the highest.Then,the discharge intensity continues to increase,producing more heat,which will decompose the ozone and lower the production of reactive oxygen species.The oxygen plasma reactor has an optimum working pressure at different input powers,which makes the oxygen plasma reactor the most efficient in generating reactive oxygen species.展开更多
Matching optimization of resonant parameters among the high power inverters,low power transformers and plasma reactors have significant effects on the performance and output of the reactor array when applying the part...Matching optimization of resonant parameters among the high power inverters,low power transformers and plasma reactors have significant effects on the performance and output of the reactor array when applying the partitioned operation method.In this paper,the Matlab/Simulink electrical model was established based on the method of partitioned operation.The matching relation between resonant parameters is analyzed on the basis of experimental result.As a consequence,transformer leakage inductance and working frequency are the important parameters influencing the operational efficiency of system,leakage inductance of transformer should be adjusted based on the equivalent capacitance of plasma reactor to realize the matching optimization of resonant parameters.展开更多
BACKGROUND Currently,endoscopic retrograde cholangiopancreatography(ERCP)plus laparoscopic cholecystectomy(LC)is the main treatment for cholecystolithiasis combined with choledocholithiasis.However,the treatment is un...BACKGROUND Currently,endoscopic retrograde cholangiopancreatography(ERCP)plus laparoscopic cholecystectomy(LC)is the main treatment for cholecystolithiasis combined with choledocholithiasis.However,the treatment is unsatisfactory,and the development of better therapies is needed.AIM To determine the clinical efficacy of LC plus cholangioscopy for cholecystolithiasis combined with choledocholithiasis.METHODS Patients(n=243)with cholecystolithiasis and choledocholithiasis admitted to The Affiliated Haixia Hospital of Huaqiao University(910th Hospital of Joint Logistic Support Force)between January 2019 and December 2023 were included in the study;111 patients(control group)underwent ERCP+LC and 132 patients(observation group)underwent LC+laparoscopic common bile duct exploration(LCBDE).Surgical success rates,residual stone rates,complications(pancreatitis,hyperamylasemia,biliary tract infection,and bile leakage),surgical indicators[intraoperative blood loss(IBL)and operation time(OT)],recovery indices(postoperative exhaust/defecation time and hospital stay),and serum inflammatory markers[C-reactive protein(CRP)],tumor necrosis factor-α(TNF-α),and interleukin-6(IL-6)were compared.RESULTS No significant differences in surgical success rates and residual stone rates were detected between the observation and control groups.However,the complication rate,IBL,OT,postoperative exhaust/defecation time,and hospital stays were significantly reduced in the observation group compared with the control group.Furthermore,CRP,TNF-α,and IL-6 Levels after treatment were reduced in the observation group compared with the levels in the control group.CONCLUSION These results indicate that LC+LCBDE is safer than ERCP+LC for the treatment of cholecystolithiasis combined with choledocholithiasis.The surgical risks and postoperative complications were lower in the observation group compared with the control group.Thus,patients may recover quickly with less inflammation after LCBDE.展开更多
Con ventio nal liquid electrolytes based sodium metal batteries suffer from severe safety hazards owing to electrolyte leakage,in flammability and dendritic sodium deposit!on.Herein,we report a flame-retardant quasi-s...Con ventio nal liquid electrolytes based sodium metal batteries suffer from severe safety hazards owing to electrolyte leakage,in flammability and dendritic sodium deposit!on.Herein,we report a flame-retardant quasi-solid polymer electrolyte with poly(methyl vinyl ether-alt-maleic an hydride)(P(MVE-alt-MA))as host,bacterial cellulose(BC)as reinforceme nt,and triethyl phosphate/vinyle ne carb on ate/sodium perchlorate(TEP/VC/NaClO4)as plasticizer for highly safe sodium metal batteries.The as-obtained quasi-solid polymer electrolyte exhibits superior flame retardancy(self-extinguish within 1 s),complete non-leakage property and wide electrochemical windows(4.4 V).More importantly,Na3V2(PO4)3/Na metal batteries using such polymer electrolyte delivers superior I on g-term cycli ng stability(84.4%capacity rete ntion after 1000 cycles)which is significantly better than that(only 2%after 240 cycles)of liquid electrolyte.In addition,this flame-retardant quasi-solid polymer electrolyte provides favorable cycle performance(80.2%capacity retention after 70 cycles at 50°C and 84.8%capacity retention after 50 cycles at-10°C)for Na3V2(PO4)3/Na metal batteries.And this battery also displayed a normal charge/discharge property even at-15°C.These fascinating cycle properties are mainly ascribed to the effective pro怕ctive layers formed on Na3V2(PC>4)3 cathode and sodium metal ano de.More thorough in vestigati on elucidates that such flame-retardant quasi-solid polymer electrolyte plays a multif unctional role in the adva need sodium metal batteries:(1)being in volved in the formatio n of a favorable cathode electrolyte in terface(CEI)to inhibit the dissolutio n of van adium and maintai n the structure integrity of the Na3V2(PO4)3;(2)participati ng in building a stable solid electrolyte in terface(SEI)to suppress the growth of Na dendrites;(3)integrating flame-retardanee into polymer sodium batteries to enhance flame-resistanee,eliminate electrolyte leakage,and thus improve safety of sodium batteries.Based on these results,we further assembled Na3V2(PO4)3/MoS2 pouch cell which can withsta nd harsh conditions(be nded or cut off a corn er),confirming the obtai ned polymer electrolyte with superior non-leakage property.In all,these outstanding characteristics would endow this flame-retardant quasi-solid polymer electrolyte a very promising can didate for highly-safe sodium metal batteries.展开更多
The gradient porous Ti3Zr2Sn3Mo25Nb(TLM)alloy rods were fabricated through sintering the alloyed powder to a solid core.The porous sample was then modified by a Micro Arc Oxidation(MAO)treatment in an electrolyte cont...The gradient porous Ti3Zr2Sn3Mo25Nb(TLM)alloy rods were fabricated through sintering the alloyed powder to a solid core.The porous sample was then modified by a Micro Arc Oxidation(MAO)treatment in an electrolyte containing calcium and phosphate,a hydrothermal treatment enabled secondary microporous hydroxyapatite(HA)coating,and a further bone morphogenetic protein-2(BMP-2)loading treatment through immersion and freeze-drying.The treatment led to an orderly secondary microporous coating containing HA nano-particles and evenly distributed BMP-2 in the porous coatings.As a result,osteoblasts could adhere and grow well on the coatings with a high cell adhesion rate and cell functional activity.The in-situ shear testing indicated that the interfacial strength had been enhanced significantly.Improvement of the bond formation and osseointegration with the titanium implant is attributed to increased surface area for the cell to attach,creating voids for the cell to grow in,and activating titanium surface by introducing bioactive ingredients such as HA and BMP-2.展开更多
This paper proposes a neural-network-based state estimation(NNSE)method that aims to achieve higher time efficiency,improved robustness against noise,and extended observability when compared with the conventional weig...This paper proposes a neural-network-based state estimation(NNSE)method that aims to achieve higher time efficiency,improved robustness against noise,and extended observability when compared with the conventional weighted least squares(WLS)state estimation method.NNSE consists of two parts,the linear state estimation neural network(LSE-net)and the unobservable state estimation neural network(USE-net).The LSE-net functions as an adaptive approximator of linear state estimation(LSE)equations to estimate the nominally observable states.The inputs of LSE-net are the vectors of synchrophasors while the outputs are the estimated states.The USE-net operates as the complementary estimator on the nominally unobservable states.The inputs are the estimated observable states from LSE-net while the outputs are the estimation of nominally unobservable states.USE-net is trained off-line to approximate the veiled relationship between observable states and unobservable states.Two test cases are conducted to validate the performance of the proposed approach.The first case,which is based on the IEEE 118-bus system,shows the comprehensive performance of convergence,accuracy,and robustness of the proposed approach.The second case study adopts real-world synchrophasor measurements,and is based on the Jiangsu power grid,which is one of the largest provincial power systems in China.展开更多
Low-frequency oscillations are hazardous to power system operation,and can lead to cascading failures if not detected and mitigated in a timely manner.This paper presents a robust and automated real-time monitoring sy...Low-frequency oscillations are hazardous to power system operation,and can lead to cascading failures if not detected and mitigated in a timely manner.This paper presents a robust and automated real-time monitoring system for detecting grid oscillations and analyzing their mode shapes using PMU measurements.A novel Extended Kalman Filtering(EKF)based approach is introduced to detect and analyze oscillations.To further improve the accuracy and efficiency of the presented software system,the EKF approach takes advantages of three effective signal processing methods(including Prony’s Method,Hankel Total Least Square(HTLS)Method,EKF)and adopts a novel voting schema to significantly reduce the computation cost.Results from these methods are processed through a timeseries filter to ensure the consistency of detected oscillations and reduce the number of false alarms.The Density-based Spatial Clustering of Applications with Noise(DBSCAN)method is used to accurately classify oscillation modes and the PMU measurement channels.The LFODA system has been functioning well in the State Grid Jiangsu Electric Power Company with 176 PMUs and 1000+channels since February 2018,demonstrating outstanding performance in reducing false alarms with much less computational cost.展开更多
With more data-driven applications introduced in wide-area monitoring systems(WAMS),data quality of phasor measurement units(PMUs)becomes one of the fundamental requirements for ensuring reliable WAMS applications.Thi...With more data-driven applications introduced in wide-area monitoring systems(WAMS),data quality of phasor measurement units(PMUs)becomes one of the fundamental requirements for ensuring reliable WAMS applications.This paper proposes a doubly-fed deep learning method for bad data identification in linear state estimation,which can:(1)identify bad data under both steady states and contingencies;(2)achieve higher accuracy than conventional pre-filtering approaches;(3)reduce iteration burden for linear state estimation;(4)efficiently identify bad data in a parallelizable scheme.The proposed method consists of four key steps:(1)preprocessing filter;(2)online training of short-term deep neural network;(3)offline training of long-term deep neural network;(4)a decision merger.Through delicate design and comprehensive training,the proposed method can effectively differentiate the bad data from event data without relying on real-time topology information.An IEEE 39-bus system simulated by DSATools TSAT and a provincial electric power system with real PMU data collected are used to verify the proposed method.Multiple test scenarios are applied,which include steady states,three-phase-to-ground faults with(un)successful auto-reclosing,low-frequency oscillation,and low-frequency oscillation with simultaneous threephase-to-ground faults.The proposed method demonstrates satisfactory performance during both the training session and the testing session.展开更多
To verify the formation behaviors and mechanisms of intra-granular acicular ferrite（ IAF） grains nucleated by Mg-Al-O in low carbon steel,the steels containing different Mg contents were refined in a vacuum inductio...To verify the formation behaviors and mechanisms of intra-granular acicular ferrite（ IAF） grains nucleated by Mg-Al-O in low carbon steel,the steels containing different Mg contents were refined in a vacuum induction furnace. The effect of Mg addition on the formation of IAF structure in Al-killed low carbon steel was investigated by optical microscope（ OM） and scanning electron microscope with energy dispersive X-ray spectroscope（ SEM-EDX）. It reveals that the IAFs are only detected in Mg-added steels,and the volume fraction of IAF increases with the Mg concentration from 8 × 10^（-6） to 26 × 10^（-6）. It shows that not only the MgO-Al_2O_3-MnS and MgO-Al_2O_3-P_2O_5 particles are the effective nucleation sites for IAF,but also the pure MgO·Al_2O_3 phase can promote the ferrite nucleation. A Mn-depletion zone（ MDZ） is characterized adjacent to the MgO-Al_2O_3-MnS,which is believed to be one of the possible mechanisms to explain the IAF nucleation. The MDZ around the MgO-Al_2O_3-MnS inclusion would be induced by the Mn S precipitation on the inclusion. It seems that the ability of Mg-containing inclusions to induce the nucleation of ferrite might be attributed to a new mechanism,i. e.,the Prich zone formed on a few Mg-Al-O inclusions might be another factor for promoting the IAF formation.展开更多
Online estimation of electromechanical oscillation parameters provides essential information to prevent system instability and blackout and helps to identify event categories and locations.We formulate the problem as ...Online estimation of electromechanical oscillation parameters provides essential information to prevent system instability and blackout and helps to identify event categories and locations.We formulate the problem as a state space model and employ the extended Kalman filter to estimate oscillation frequencies and damping factors directly based on data from phasor measurement units.Due to considerations of communication burdens and privacy concerns,a fully distributed algorithm is proposed using diffusion extended Kalman filter.The effectiveness of proposed algorithms is confirmed by both simulated and real data collected during events in State Grid Jiangsu Electric Power Company.展开更多
基金Key Project of Party Building and Ideological and Political Education Research from University of Science and Technology Liaoning for the Year 2023(2023KDDJ-X01)awarded to Zhe Yu.
文摘This study aims to revise the Belief in a Just World Scale(BJWS)for Chinese college students and test its reliability and validity(construct validity,convergent and divergent validity).Two samples of 546 and 595 college students were selected,respectively,using stratified cluster random sampling.Item analysis,exploratory factor analysis(EFA),confirmatory factor analysis(CFA),reliability analysis and convergent and divergent validity tests were carried out.The results showed that the 13 items of the BJWS have good item discrimination.The corrected item–total correlation in the general belief in a just world subscale was found to range from 0.464 to 0.655,and that in the personal belief in a just world subscale was 0.553 to 0.715.The internal consistency coefficients of the revised version of the BJWS and its subscales are good.The EFA and CFA results show that the structure and items of the revised scale are the same as those of the original scale.Belief in a just world was found to have significant positive correlations with gratitude and empathy,and has a significant negative correlation with anxiety,thereby exhibiting good convergent and divergent validity.Therefore,the Chinese revised version of the BJWS has good reliability and validity.
基金supported by the National Social Science Foundation of China(No.14ZDB014,No.17ZDA026)the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement(No.690974)
基金financially supported by the National Key R&D Program of China (Grant No. 2017YFE0127600)the National Natural Science Foundation of China (Nos. 51703236 and U1706229)+1 种基金the National Science Fund for Distinguished Young Scholars (No. 51625204)Key Scientific and Technological Innovation Project of Shandong (No. 2017CXZC0505)。
文摘Lithium–sulfur batteries have been regarded as the most promising high-energy electrochemical energy storage device owing to the high energy density, low cost and environmental friendliness. However, traditional lithium–sulfur batteries using ether-based electrolytes often suffer from severe safety risks(i.e. combustion). Herein, we demonstrated a novel kind of flame-retardant concentrated electrolyte(6.5 M lithium bis(trifluoromethylsulphonyl)imide/fluoroethylene carbonate) for highly-safe and widetemperature lithium–sulfur batteries. It was found that such concentrated electrolyte showed superior flame retardancy, high lithium-ion transference number(0.69) and steady lithium plating/stripping behavior(2.5 m Ah cm^(-2) over 3000 h). Moreover, lithium–sulfur batteries using this flame-retardant concentrated electrolyte delivered outstanding cycle performance in a wide range of temperatures(-10 °C, 25 °C and 90 °C). This superior battery performance is mainly attributed to the LiF-rich solid electrolyte interphase formed on lithium metal anode, which can effectively suppress the continuous growth of lithium dendrites. Above-mentioned fascinating characteristics would endow this flame-retardant concentrated electrolyte a very promising candidate for highly-safe and wide-temperature lithium–sulfur batteries.
文摘BACKGROUND Suspension training(SET)is a method of neuromuscular training that enables the body to carry out active training under unstable support through a suspension therapy system.However,there have been few reports in the literature on the application of SET to anterior cruciate ligament reconstruction(ACLR)patients.It is not clear what aspects of the patient's function are improved after SET.AIM To investigate the effect of SET on the neuromuscular function,postural control,and knee kinematics of patients after ACLR surgery.METHODS Forty participants were randomized to an SET group or a control group.The SET group subjects participated in a SET protocol over 6 wk.The control group subjects participated in a traditional training protocol over 6 wk.Isokinetic muscle strength of the quadriceps and hamstrings,static and dynamic posture stability test,and relative translation of the injured knee were assessed before and after training.RESULTS The relative peak torque of the quadriceps and hamstrings in both groups increased significantly(P<0.001),and the SET group increased by a higher percentage than those in the control group(quadriceps:P=0.004;hamstrings:P=0.011).After training,both groups showed significant improvements in static and dynamic posture stability(P<0.01),and the SET group had a greater change than the control group(P<0.05).No significant improvement on the relative translation of the injured knee was observed after training in either group(P>0.05).CONCLUSION Our findings show that SET promotes great responses in quadriceps and hamstring muscle strength and balance function in ACLR patients.
基金This work was supported in part by National Natural Science Foundation of China under Grant 62076199in part by the Open Research Fund of Beijing Key Laboratory of Big Data Technology for Food Safety under Grant BTBD-2020KF08+2 种基金Beijing Technology and Business University,in part by the China Postdoctoral Science Foundation under Grant 2019M653784in part by Key Laboratory of Spectral Imaging Technology of Chinese Academy of Sciences under Grant LSIT201801Din part by the Key R&D Project of Shaan’xi Province under Grant 2021GY-027。
文摘In this paper,we propose a neoteric and high-efficiency single image dehazing algorithm via contrast enhancement which is called STRASS(Spatio-Temporal Retinex-Inspired by an Averaging of Stochastic Samples)dehazing,it is realized by constructing an efficient high-pass filter to process haze images and taking the influence of human vision system into account in image dehazing principles.The novel high-pass filter works by getting each pixel using RSR and computes the average of the samples.Then the low-pass filter resulting from the minimum envelope in STRESS framework has been replaced by the average of the samples.The final dehazed image is yielded after iterations of the high-pass filter.STRASS can be run directly without any machine learning.Extensive experimental results on datasets prove that STRASS surpass the state-of-the-arts.Image dehazing can be applied in the field of printing and packaging,our method is of great significance for image pre-processing before printing.
基金supported by National Key Technology Research and Development Program of the Ministry of Science and Technology of China(No.2013BAC06B02)Public Science and Technology Research Funds Projects of Ocean(No.201305027)+2 种基金National Natural Science Foundation of China(Nos.51877024,61427804,51309039)Liaoning Scientific Research Project of Department of Education of Liaoning Province(No.LZ2015007)High Level Talent Innovation Project of Dalian(No.2016RQ040)
文摘The oxygen plasma reactor based on dielectric barrier discharge principle can produce a high concentration of reactive oxygen species,which can cooperate with hydraulic cavitation gas-liquid mixer to realize the application of advanced oxidation technology in water treatment.In this technology,the work pressure of the oxygen plasma reactor is decreased by the vacuum suction effect generated in the snap-back section of the gas-liquid mixed container.In this paper,the characteristics of single micro-discharge at different pressures were investigated with the methods of discharge image,electrical characteristics and spectral diagnosis,in order to analyze the electrical characteristics and reactive oxygen species generation efficiency of oxygen plasma reactor at the pressure range from 60 kPa to 100 kPa.The study indicated that,when the pressure decreases,the duty ratio of ionization in the discharge gap and number of electrons with high energy increases,leading to a rise in reactive oxygen species production.When the oxygen reaches the maximum ionization,the concentration of reactive oxygen species is the highest.Then,the discharge intensity continues to increase,producing more heat,which will decompose the ozone and lower the production of reactive oxygen species.The oxygen plasma reactor has an optimum working pressure at different input powers,which makes the oxygen plasma reactor the most efficient in generating reactive oxygen species.
基金supported by National Key Technology Research and Development Program of the Ministry of Science and Technology of China(No.2013BAC06B02)Public Science and Technology Research Funds Projects of Ocean (No.201305027)+2 种基金National Natural Science Foundation of China(No.51877024)Liaoning Scientific Research Project of Department of Education of Liaoning Province(No.LZ2015007)High Level Talent Innovation Project of Dalian(No.2016RQ040)
文摘Matching optimization of resonant parameters among the high power inverters,low power transformers and plasma reactors have significant effects on the performance and output of the reactor array when applying the partitioned operation method.In this paper,the Matlab/Simulink electrical model was established based on the method of partitioned operation.The matching relation between resonant parameters is analyzed on the basis of experimental result.As a consequence,transformer leakage inductance and working frequency are the important parameters influencing the operational efficiency of system,leakage inductance of transformer should be adjusted based on the equivalent capacitance of plasma reactor to realize the matching optimization of resonant parameters.
文摘BACKGROUND Currently,endoscopic retrograde cholangiopancreatography(ERCP)plus laparoscopic cholecystectomy(LC)is the main treatment for cholecystolithiasis combined with choledocholithiasis.However,the treatment is unsatisfactory,and the development of better therapies is needed.AIM To determine the clinical efficacy of LC plus cholangioscopy for cholecystolithiasis combined with choledocholithiasis.METHODS Patients(n=243)with cholecystolithiasis and choledocholithiasis admitted to The Affiliated Haixia Hospital of Huaqiao University(910th Hospital of Joint Logistic Support Force)between January 2019 and December 2023 were included in the study;111 patients(control group)underwent ERCP+LC and 132 patients(observation group)underwent LC+laparoscopic common bile duct exploration(LCBDE).Surgical success rates,residual stone rates,complications(pancreatitis,hyperamylasemia,biliary tract infection,and bile leakage),surgical indicators[intraoperative blood loss(IBL)and operation time(OT)],recovery indices(postoperative exhaust/defecation time and hospital stay),and serum inflammatory markers[C-reactive protein(CRP)],tumor necrosis factor-α(TNF-α),and interleukin-6(IL-6)were compared.RESULTS No significant differences in surgical success rates and residual stone rates were detected between the observation and control groups.However,the complication rate,IBL,OT,postoperative exhaust/defecation time,and hospital stays were significantly reduced in the observation group compared with the control group.Furthermore,CRP,TNF-α,and IL-6 Levels after treatment were reduced in the observation group compared with the levels in the control group.CONCLUSION These results indicate that LC+LCBDE is safer than ERCP+LC for the treatment of cholecystolithiasis combined with choledocholithiasis.The surgical risks and postoperative complications were lower in the observation group compared with the control group.Thus,patients may recover quickly with less inflammation after LCBDE.
基金This original research was financially supported by the National Natural Science Foundation of China(Nos.51703236 and U1706229)the National Science Fund for Distinguished Young Scholars(No.51625204)+1 种基金the National Key Research and Development Program of China(No.2018YFB0104300)Think-Tank Mutual Fund of Qingdao Energy Storage Industry Scientific Research,Key Scientific and Technological Innovation Project of Shandong(No.2017CXZC0505).
文摘Con ventio nal liquid electrolytes based sodium metal batteries suffer from severe safety hazards owing to electrolyte leakage,in flammability and dendritic sodium deposit!on.Herein,we report a flame-retardant quasi-solid polymer electrolyte with poly(methyl vinyl ether-alt-maleic an hydride)(P(MVE-alt-MA))as host,bacterial cellulose(BC)as reinforceme nt,and triethyl phosphate/vinyle ne carb on ate/sodium perchlorate(TEP/VC/NaClO4)as plasticizer for highly safe sodium metal batteries.The as-obtained quasi-solid polymer electrolyte exhibits superior flame retardancy(self-extinguish within 1 s),complete non-leakage property and wide electrochemical windows(4.4 V).More importantly,Na3V2(PO4)3/Na metal batteries using such polymer electrolyte delivers superior I on g-term cycli ng stability(84.4%capacity rete ntion after 1000 cycles)which is significantly better than that(only 2%after 240 cycles)of liquid electrolyte.In addition,this flame-retardant quasi-solid polymer electrolyte provides favorable cycle performance(80.2%capacity retention after 70 cycles at 50°C and 84.8%capacity retention after 50 cycles at-10°C)for Na3V2(PO4)3/Na metal batteries.And this battery also displayed a normal charge/discharge property even at-15°C.These fascinating cycle properties are mainly ascribed to the effective pro怕ctive layers formed on Na3V2(PC>4)3 cathode and sodium metal ano de.More thorough in vestigati on elucidates that such flame-retardant quasi-solid polymer electrolyte plays a multif unctional role in the adva need sodium metal batteries:(1)being in volved in the formatio n of a favorable cathode electrolyte in terface(CEI)to inhibit the dissolutio n of van adium and maintai n the structure integrity of the Na3V2(PO4)3;(2)participati ng in building a stable solid electrolyte in terface(SEI)to suppress the growth of Na dendrites;(3)integrating flame-retardanee into polymer sodium batteries to enhance flame-resistanee,eliminate electrolyte leakage,and thus improve safety of sodium batteries.Based on these results,we further assembled Na3V2(PO4)3/MoS2 pouch cell which can withsta nd harsh conditions(be nded or cut off a corn er),confirming the obtai ned polymer electrolyte with superior non-leakage property.In all,these outstanding characteristics would endow this flame-retardant quasi-solid polymer electrolyte a very promising can didate for highly-safe sodium metal batteries.
基金financial support of the National Natural Science Foundation of China(32071327)National Key Research and Development Program of China(2016YFC1102003)+2 种基金International Science and Technology Cooperation Base of Shaanxi Province(2017GHJD-014)Science and Technology Program of Shaanxi Province(2019GY-200)Key Research and Development Program of Shaanxi Province(2019ZDLSF03-06)。
文摘The gradient porous Ti3Zr2Sn3Mo25Nb(TLM)alloy rods were fabricated through sintering the alloyed powder to a solid core.The porous sample was then modified by a Micro Arc Oxidation(MAO)treatment in an electrolyte containing calcium and phosphate,a hydrothermal treatment enabled secondary microporous hydroxyapatite(HA)coating,and a further bone morphogenetic protein-2(BMP-2)loading treatment through immersion and freeze-drying.The treatment led to an orderly secondary microporous coating containing HA nano-particles and evenly distributed BMP-2 in the porous coatings.As a result,osteoblasts could adhere and grow well on the coatings with a high cell adhesion rate and cell functional activity.The in-situ shear testing indicated that the interfacial strength had been enhanced significantly.Improvement of the bond formation and osseointegration with the titanium implant is attributed to increased surface area for the cell to attach,creating voids for the cell to grow in,and activating titanium surface by introducing bioactive ingredients such as HA and BMP-2.
基金This work was supported by the State Grid Corporation of China(No.SGJS0000DKJS1801231).
文摘This paper proposes a neural-network-based state estimation(NNSE)method that aims to achieve higher time efficiency,improved robustness against noise,and extended observability when compared with the conventional weighted least squares(WLS)state estimation method.NNSE consists of two parts,the linear state estimation neural network(LSE-net)and the unobservable state estimation neural network(USE-net).The LSE-net functions as an adaptive approximator of linear state estimation(LSE)equations to estimate the nominally observable states.The inputs of LSE-net are the vectors of synchrophasors while the outputs are the estimated states.The USE-net operates as the complementary estimator on the nominally unobservable states.The inputs are the estimated observable states from LSE-net while the outputs are the estimation of nominally unobservable states.USE-net is trained off-line to approximate the veiled relationship between observable states and unobservable states.Two test cases are conducted to validate the performance of the proposed approach.The first case,which is based on the IEEE 118-bus system,shows the comprehensive performance of convergence,accuracy,and robustness of the proposed approach.The second case study adopts real-world synchrophasor measurements,and is based on the Jiangsu power grid,which is one of the largest provincial power systems in China.
基金This work is supported by SGCC Science and Technology Program under project“AI based oscillation detection and control”(SGJS0000DKJS1801231).
文摘Low-frequency oscillations are hazardous to power system operation,and can lead to cascading failures if not detected and mitigated in a timely manner.This paper presents a robust and automated real-time monitoring system for detecting grid oscillations and analyzing their mode shapes using PMU measurements.A novel Extended Kalman Filtering(EKF)based approach is introduced to detect and analyze oscillations.To further improve the accuracy and efficiency of the presented software system,the EKF approach takes advantages of three effective signal processing methods(including Prony’s Method,Hankel Total Least Square(HTLS)Method,EKF)and adopts a novel voting schema to significantly reduce the computation cost.Results from these methods are processed through a timeseries filter to ensure the consistency of detected oscillations and reduce the number of false alarms.The Density-based Spatial Clustering of Applications with Noise(DBSCAN)method is used to accurately classify oscillation modes and the PMU measurement channels.The LFODA system has been functioning well in the State Grid Jiangsu Electric Power Company with 176 PMUs and 1000+channels since February 2018,demonstrating outstanding performance in reducing false alarms with much less computational cost.
基金supported by the Science and Technology Program of State Grid Corporation of China under project“AI based oscillation detection and control”(No.SGJS0000DKJS1801231)
文摘With more data-driven applications introduced in wide-area monitoring systems(WAMS),data quality of phasor measurement units(PMUs)becomes one of the fundamental requirements for ensuring reliable WAMS applications.This paper proposes a doubly-fed deep learning method for bad data identification in linear state estimation,which can:(1)identify bad data under both steady states and contingencies;(2)achieve higher accuracy than conventional pre-filtering approaches;(3)reduce iteration burden for linear state estimation;(4)efficiently identify bad data in a parallelizable scheme.The proposed method consists of four key steps:(1)preprocessing filter;(2)online training of short-term deep neural network;(3)offline training of long-term deep neural network;(4)a decision merger.Through delicate design and comprehensive training,the proposed method can effectively differentiate the bad data from event data without relying on real-time topology information.An IEEE 39-bus system simulated by DSATools TSAT and a provincial electric power system with real PMU data collected are used to verify the proposed method.Multiple test scenarios are applied,which include steady states,three-phase-to-ground faults with(un)successful auto-reclosing,low-frequency oscillation,and low-frequency oscillation with simultaneous threephase-to-ground faults.The proposed method demonstrates satisfactory performance during both the training session and the testing session.
基金Item Sponsored by National Natural Science Foundation of China(51374059,51374060)Scientific Research Fund of Liaoning Provincial Education Department of China(2012221013)
文摘To verify the formation behaviors and mechanisms of intra-granular acicular ferrite（ IAF） grains nucleated by Mg-Al-O in low carbon steel,the steels containing different Mg contents were refined in a vacuum induction furnace. The effect of Mg addition on the formation of IAF structure in Al-killed low carbon steel was investigated by optical microscope（ OM） and scanning electron microscope with energy dispersive X-ray spectroscope（ SEM-EDX）. It reveals that the IAFs are only detected in Mg-added steels,and the volume fraction of IAF increases with the Mg concentration from 8 × 10^（-6） to 26 × 10^（-6）. It shows that not only the MgO-Al_2O_3-MnS and MgO-Al_2O_3-P_2O_5 particles are the effective nucleation sites for IAF,but also the pure MgO·Al_2O_3 phase can promote the ferrite nucleation. A Mn-depletion zone（ MDZ） is characterized adjacent to the MgO-Al_2O_3-MnS,which is believed to be one of the possible mechanisms to explain the IAF nucleation. The MDZ around the MgO-Al_2O_3-MnS inclusion would be induced by the Mn S precipitation on the inclusion. It seems that the ability of Mg-containing inclusions to induce the nucleation of ferrite might be attributed to a new mechanism,i. e.,the Prich zone formed on a few Mg-Al-O inclusions might be another factor for promoting the IAF formation.
基金This work is supported by the Science and Technology Project of State Grid Corporation(No.5455HJ160007).
文摘Online estimation of electromechanical oscillation parameters provides essential information to prevent system instability and blackout and helps to identify event categories and locations.We formulate the problem as a state space model and employ the extended Kalman filter to estimate oscillation frequencies and damping factors directly based on data from phasor measurement units.Due to considerations of communication burdens and privacy concerns,a fully distributed algorithm is proposed using diffusion extended Kalman filter.The effectiveness of proposed algorithms is confirmed by both simulated and real data collected during events in State Grid Jiangsu Electric Power Company.
