A new probe for atmospheric electric field mill is introduced.It consists of three parts:signal acquisition circuit for atmospheric electric field,preamplifier circuit and phase sensitive detection circuit.The signal...A new probe for atmospheric electric field mill is introduced.It consists of three parts:signal acquisition circuit for atmospheric electric field,preamplifier circuit and phase sensitive detection circuit.The signal acquisition circuit adopts the double-stator structure to form differential input circuit,thus double-precision is obtained.Preamplifier circuit is made of current-to-voltage (I-V) conversion circuit,differential amplifier circtuit and secondary amplifying circuit.The polarity of electric field is obtained via phase sensitive detection circuit.Simulation results are obtained using Multisim,and the feasibility of the designed probe is verified.展开更多
High-energy electron precipitation in the high latitude regions enhances the ionization of the atmosphere,and subsequently increases the atmospheric conductivities and the vertical electric field of the atmosphere nea...High-energy electron precipitation in the high latitude regions enhances the ionization of the atmosphere,and subsequently increases the atmospheric conductivities and the vertical electric field of the atmosphere near the ground as well.The High-Energy Electron Flux(HEEF) data measured by the Fengyun-3 meteorological satellite are analyzed together with the data of nearsurface atmospheric vertical electric field measured at the Russian Vostok Station.Three HEEF enhancements are identified and it is shown that when the HEEF increases to a certain level,the local atmospheric vertical electric field near the ground can increase substantially than usual.The response time of the electric field to HEEF enhancement is about 3.7 to 4 days.展开更多
In this paper, an improved air discharge fluid model under non-uniform electric field is constructed based on the plasma module COMSOL Multiphysics with artificial stability term, and the boundary conditions developed...In this paper, an improved air discharge fluid model under non-uniform electric field is constructed based on the plasma module COMSOL Multiphysics with artificial stability term, and the boundary conditions developed in the previous paper are applied to the calculation of photoionization rate. Based on the modified model, the characteristics of low temperature subatmospheric air discharge under 13 kV direct current voltage are discussed, including needle-plate and needle-needle electrode structures. Firstly, in order to verify the reliability of the model, a numerical example and an experimental verification were carried out for the modified model respectively. Both verification results show that the model can ensure the accuracy and repeatability of the calculation. Secondly, according to the calculation results of the modified model, under the same voltage and spacing, the reduced electric field under low temperature subatmosphere pressure is larger than that under normal temperature and atmospheric pressure. The high electric field leads to the air discharge at low temperature and sub atmospheric pressure entering the streamer initiation stage earlier, and has a faster propagation speed in the streamer development stage, which shortens the overall discharge time. Finally, the discharge characteristics of the two electrode structures are compared, and it is found that the biggest difference between them is that there is a pre-ionization region near the cathode in the needle-needle electrode structure. When the pre-ionization level reaches 1013 cm-3, the propagation speed of the positive streamer remains unchanged throughout the discharge process, and is no longer affected by the negative streamer. The peak value of electric field decreases with the increase of pre-ionization level, and tends to be constant during streamer propagation. Based on the previous paper, this paper constructs the air discharge model under non-uniform electric field, complements with the previous paper, and forms a relatively complete set of air discharge simulation system under low temperature and sub atmospheric pressure, which provides a certain reference for future research.展开更多
Data loss or distortion causes adverse effects on the accuracy and stability of the thunderstorm point charge localization.To solve this problem,we propose a data complementary method based on the atmospheric electric...Data loss or distortion causes adverse effects on the accuracy and stability of the thunderstorm point charge localization.To solve this problem,we propose a data complementary method based on the atmospheric electric field apparatus array group.The electric field component measurement model of the atmospheric electric field apparatus is established,and the orientation parameters of the thunderstorm point charge are defined.Based on the mirror method,the thunderstorm point charge coordinates are obtained by using the potential distribution formulas.To test the validity of the basic algorithm,the electric field component measurement error and the localization accuracy are studied.Besides the azimuth angle and the elevation angle,the localization parameters also include the distance from the apparatus to the thunderstorm cloud.Based on a primary electric field apparatus,we establish the array group of apparatuses.Based on this,the data measured by each apparatus is complementarily processed to regain the thunderstorm point charge position.The results show that,compared with the radar map data,this method can accurately reflect the location of the thunderstorm point charge,and has a better localization effect.Additionally,several observation results during thunderstorm weather have been presented.展开更多
In this work,the effects of the methane gas flow and the internal oscillating electric field between electrodes on radio-frequency(RF)atmospheric pressure argon/methane plasma jet and process of diamond-like carbon(DL...In this work,the effects of the methane gas flow and the internal oscillating electric field between electrodes on radio-frequency(RF)atmospheric pressure argon/methane plasma jet and process of diamond-like carbon(DLC)film deposition have been investigated.Properties of RF atmospheric Ar/methane plasma jet such as active species density,length,electron temperature,appearance and ionization process of argon/methane plasma jet are changed due to the changing of methane flow content and electric field vector and its gradient.With increasing methane flow,the formation of C2 hydrocarbon and CH band content is decreased because injected electrical energy to a mixture of Ar/methane gases is insufficient to stabilize the ionization process of methane gas and the electrical-chemical reaction rate is decreased.With shortening the gas gap between two electrodes,electric field strength and its gradient are increased leading to more energy injection to the electron.Electrical-chemical reactions are strengthened leading to increasing the CH band content.These phenomena introduce the Ar/methane plasma jet in different modes causing to deposit the DLC film with different structures and properties.With using quartz glass and alumina ceramic as dielectric barriers tubes,RF atmospheric pressure Ar/methane plasma jet has been used to deposit DLC coating in different modes.Increasing methane content and shortening the gas gap leads to decreasing sp3 bonded content and the quality of the deposited film.展开更多
The paper presents research data on positive and negative coronas inatmospheric pressure air in a highly inhomogeneous electric field. Thedata show that irrespective of the polarity of pointed electrodes placed ina hi...The paper presents research data on positive and negative coronas inatmospheric pressure air in a highly inhomogeneous electric field. Thedata show that irrespective of the polarity of pointed electrodes placed ina high electric field (200 kV/cm), this type of discharge develops via ballstreamers even if the gap voltage rises slowly (0.2 kV/ms). The start voltageof first positive streamers, compared to negative ones, is higher andthe amplitude and the frequency of their current pulses are much lower:about two times and more than two orders of magnitude, respectively.The higher frequency of current pulses from negative streamers provideshigher average currents and larger luminous areas of negative coronascompared to positive ones. Positive and negative cylindrical streamersfrom a pointed to a plane electrode are detected and successive dischargetransitions at both polarities are identified.展开更多
This article proposes the hybrid method to inverse the equivalent electric charge of thunder cloud based on the data of multi-station atmospheric electric field. Firstly,the method combines the genetic algorithm( GA) ...This article proposes the hybrid method to inverse the equivalent electric charge of thunder cloud based on the data of multi-station atmospheric electric field. Firstly,the method combines the genetic algorithm( GA) and New ton method through the mosaic hybrid structure. In addition,the thunder cloud equivalent charge is inversed based on the forw ard modeling results by giving the parameters of the thunder cloud charge structure. Then an ideal model is built to examine the performance compared to the nonlinear least squares method. Finally,a typical thunderstorms process in Nanjing is analyzed by Genetic-New ton algorithm with the help of weather radar. The results show the proposed method has the strong global searching capability so that the problem of initial value selection can be solved effectively,as well as gets the better inversion results. Furthermore,the mosaic hybrid structure can absorb the advantages of tw o algorithms better,and the inversion position is consistent with the strongest radar echo.The inversion results find the upper negative charge is small and can be ignored,w hich means the triple-polarity charge structure is relatively scientific,w hich could give some references to the research like lightning forecasting,location tracking.展开更多
The long time practice of observational research on earthquake prediction has shown that the information on shortterm and imminent earthquake precursors can hardly be detected, but it is very important for practical ...The long time practice of observational research on earthquake prediction has shown that the information on shortterm and imminent earthquake precursors can hardly be detected, but it is very important for practical and effective earthquake prediction. The result of analysis and study in this paper has shown that the anomaly of quasi static atmospheric electric field may be a kind of reliable information on short term and imminent earthquake precursors.On such a basis, the 20 years′ continuous and reliable data of atmospheric electric field observed at the Baijiatuan seismic station are used to study the correlation between the anomalies in seismic activity and relative quiet periods bear on the occurrence of near earthquakes within 200 km range around Beijing after the Tangshan earthquake. The observational results recently reported before hand in written form and earthquakes that actually occurred in near field in corresponding time periods are compared and analyzed. The efficacy of these written prediction opinions about near earthquakes in the recent 10 years is tested. From the test results, the brilliant prospect that the anomaly of quasi static atmospheric electric field may really become a reliable mark for making short term and imminent earthquake predictions is discussed. Besides, as a preliminary step, some judgment indexes for predicting earthquakes by use of the observational data of atmospheric electric field before earthquakes are put forward. In the last part, it is pointed out that it would be possible to obtain more believable judgment indexes for determining the three elements of near earthquakes before greater earthquakes ( M S5) only if a relatively reasonable station network (2~4 stations every 10 000 km 2) is deployed and further investigation is made.展开更多
[Objective] The research aimed to analyze characteristics of atmospheric electric field in polluted area. [Method] By using data of atmospheric electric field meter in Taiyuan in 2009, daily and annual changes of atmo...[Objective] The research aimed to analyze characteristics of atmospheric electric field in polluted area. [Method] By using data of atmospheric electric field meter in Taiyuan in 2009, daily and annual changes of atmospheric electric field in Taiyuan were analyzed. [ Result] Atmospheric electric field intensity in Taiyuan was higher than that in other areas. Daily change was double-peak double-valley type. The first highest value appeared at nightfall, and the second highest value was before the noon. The first lowest value appeared in early morning, while the second low- est value appeared after the noon. Annual change was single-peak single-valley type. The maximum appeared in winter, while the minimum ap- peared in summer. [ Conclusion] When forecasting thunderstorm, in the area with higher aerosol content, alarm threshold of electric field should be adjusted via comparison with actual observation, which had very strong regional characteristics. By analyzing real-time monitoring data of atmospheric electric field, thunderstorm forecast could be realized, and timeliness and accuracy of warning and forecast could be increased.展开更多
Based on ground observation,lightning locator and atmospheric electric field instrument data,the characteristics of lightning and atmospheric electric field in Nanchang County were analyzed. The warning effect of the ...Based on ground observation,lightning locator and atmospheric electric field instrument data,the characteristics of lightning and atmospheric electric field in Nanchang County were analyzed. The warning effect of the atmospheric electric field instruments on lightning was studied,and the threshold of some atmospheric electric field instruments was adjusted according to the expectation of the warning accuracy rate. In Nanchang County,the annual number of thunderstorm days averaged 48. 6. Lightning mainly occurred from March to August,with a maximum of 8. 8 d in August. The lightning areas were mainly concentrated in the south,followed by the north,and the frequency of lightning in the middle was relatively low. The diurnal variation of lightning was obvious,and lightning happened most frequently from afternoon to evening. Five atmospheric electric field instruments were set up according to the lightning areas of Nanchang County. The average electric field intensity on a sunny day was 0. 06,0. 05,0. 16,0. 07,and 0. 17 kV/m respectively,with certain seasonal variations. The field intensity in June was the lowest in the whole year. The atmospheric electric field on a sunny day also had obvious diurnal variation characteristics,generally presenting the characteristics of double peaks and double valleys. The first peak of atmospheric electric field intensity appeared one hour later than that of relative humidity,and then the change trends were relatively consistent. After the adjustment,the warning accuracy rate of the atmospheric electric field instruments was greatly improved to meet the expectation.展开更多
From April 1st to August 14th, 2006, thunderstorms had been recorded at Yangbajing Cosmic Ray Observatory by ARGO-YBJ experiment. This paper analyzed the correlation between atmospheric electric field (AEF) and "sc...From April 1st to August 14th, 2006, thunderstorms had been recorded at Yangbajing Cosmic Ray Observatory by ARGO-YBJ experiment. This paper analyzed the correlation between atmospheric electric field (AEF) and "scaler mode" counting rate during thunderstorm. Counting rates of multiplicities n=1,2 were found to have a large increase (from 1.02% to 9.03%), while there was few or no changes in those of multiplicities n=3 and n≥4 during the thunderstorms. The counts of different multiplicities had different feedbacks on the violent change of AEF, which showed that their energy and most components were distinguishing.展开更多
The association between the lunar phases and the atmospheric electric field has been investigated from the superposed epoch analysis of the long series of continuous data of the vertical electric field for Colaba, Bom...The association between the lunar phases and the atmospheric electric field has been investigated from the superposed epoch analysis of the long series of continuous data of the vertical electric field for Colaba, Bombay (18 ° 53'N, 73 ° 48'E 11 mASL) for the period 1947-1966. Also the periodicities in the atmospheric electric field have been studied from the spectral analysis of the data. The study has indicated that when the full moon is within 4 of the ecliptic plane i.e.,Bf 4 ° , the electric field peaks on the day of the full moon followed by a steep fall in the field values up to 4 days following the full moon day and there after it showed a steep increase. Also, the electric field has exhibited 5-9 day periodicity and its multiples are nearly always present. The periodicity in the electric field corresponds with the average time interval between the successive magnetic sector boundary (MSB ) crossings i.e., 7 days. On most of the occasions, the MSB crossing day is associated with a maximum of one or more of the wavelengths derived from the spectral analysis of the atmospheric electric field.展开更多
The variations noticed in the atmospheric electric field recorded at Pune (18°32'N, 73°51'E, 559 m ASL), a tropical inland station located in Dcccan Plateau, India, during the period 1930-1987, have ...The variations noticed in the atmospheric electric field recorded at Pune (18°32'N, 73°51'E, 559 m ASL), a tropical inland station located in Dcccan Plateau, India, during the period 1930-1987, have been examined in relation to the variations observed in the Angstrom turbidity coefficient (β) and selected meteorological parameters. The monthly and annual mean values of the atmospheric electric field. Angstrom turbidity coefficient (β), rainfall, temperature and relative humidity for the years 1930-1938, 1957-1958, 1964-1965, 1973-1974 and 1987 were considered in the study.The results of the above study indicated gradual increases in the atmospheric electric field over the period of study (1930-1987) which is statistically significant at less than 5%level. The increases noticed during different periods varied from 30 to 109%. The increase noticed during the period (1930-1938) and (1973-1974) was maximum (109%). The Angstrom turbidity coefficient also showed systematic increases during the period of study, which is consistent. The diurnal curve of the atmospheric electric field at the station by and large, showed a double oscillation, which is generally observed in the conlinental environments.展开更多
This paper presents a high performance electric field micro sensor with combined differential structure.The sensor consists of two backward laid micro-machined chips,each packaged by polymer and metal.The novel combin...This paper presents a high performance electric field micro sensor with combined differential structure.The sensor consists of two backward laid micro-machined chips,each packaged by polymer and metal.The novel combined differential structure effectively reduces various environmental affections,such as thermal drift,humidity drift and electrostatic charge accumulation.The sensor is tested in near-ground place as well as balloon-borne sounding.In different weather conditions,the measurement results showed good agreement with those of the commercial electric field mill.展开更多
Electric field is an important parameter of plasma,which is related to electron temperature,electron density,excited species density,and so on.In this work,the electric field of an atmospheric pressure plasma jet is d...Electric field is an important parameter of plasma,which is related to electron temperature,electron density,excited species density,and so on.In this work,the electric field of an atmospheric pressure plasma jet is diagnosed by the electric field induced second harmonic(E-FISH)method,and the time-resolved electric field under different conditions is investigated.When positive pulse voltage is applied,the electric field has a peak of about 25 kV cm-1at the rising edge of the voltage pulse.A dark channel is left behind the plasma bullet and the electric field in the dark channel is about 5 kV cm-1.On the other hand,when negative pulse voltage is applied,the electric field has a peak of-16 kV cm-1when the negative voltage is increased to-8 kV.A relatively bright channel is left behind the plasma head and the electric field in this relatively bright channel is about-6 kV cm-1.When the pulse rising time increases from 60 to 200 ns,the peak electric field at both the rising edge and the falling edge of the voltage decreases significantly.When 0.5%of oxygen is added to the main working gas helium,the peak electric field at the rising edge is only about 15 kV cm-1.On the other hand,when 0.5%nitrogen is added,the peak electric field increases especially at the falling edge of the voltage pulse,where it increases reversely from-12 to-16 kV cm-1(the minus sign only represents the direction of electric field).展开更多
A pulse generator with a voltage rise time of~1.5 ns and voltage amplitude variable from 30 kV to 200 kV was designed for generating runaway electron beams in atmospheric pressure air with different interelectrode ga...A pulse generator with a voltage rise time of~1.5 ns and voltage amplitude variable from 30 kV to 200 kV was designed for generating runaway electron beams in atmospheric pressure air with different interelectrode gaps.The influence of the voltage amplitude and gap length on the generation was studied.In the gas diode geometry under study,the gap voltage at which the generation of a runaway electron beam begins was determined.Decreasing the voltage pulse amplitude does not increase the beam current pulse width measured with a time resolution of~0.1 ns.It is shown that the escape of beam electrons to the downstream of the foil is sync in time with the voltage drop across the gap,and that the delay of beam current generation increases gradually from 1.1 ns to 2.6 ns as the voltage pulse amplitude across the gap decreases from~100 kV to 40 kV.展开更多
In this paper we have extended the semi-analytical model presented by Yashunin et al.to compute both of the lightning vertical and horizontal electric field considering the effect of nonlinear atmospheric electric par...In this paper we have extended the semi-analytical model presented by Yashunin et al.to compute both of the lightning vertical and horizontal electric field considering the effect of nonlinear atmospheric electric parameters,and validate its accuracy by using our 2-D FDTD method.It is noted that the semi-analytical model can predict not only the lightning vertical field,but also the horizontal electric field with a satisfied accuracy in a small region with a radius ranging from 5 to 30 km at a height from 80 to 90 km above the lightning strike point.Compared with the results in the free space with a vacuum,the conducting altitude atmosphere has a relatively little effect on the radiated field component,but it has much effect on the electrostatic and induction component because their duration times are longer than the local relaxation time.For example,the induction field component in the conducting nonlinear medium decreases by about 43%,compared with that in the free space with a vacuum.The induction field is larger than the radiation field component within a radius of 25 km at a height of 80 km above the lightning strike point.Therefore,although the induction component may be likely one extra energy source(except for the radiation field)for creating the pancake shape of some elves with a luminous central part,we have to take into account the effect of nonlinear atmospheric electric parameters on the prediction of induced field component peak value that is needed for the production of elves.展开更多
Atmospheric pressure glow discharge(APGD) plasma in air has high application value. In this paper, the methods of generating APGD plasma in air are discussed, and the characteristics of dielectric barrier discharge...Atmospheric pressure glow discharge(APGD) plasma in air has high application value. In this paper, the methods of generating APGD plasma in air are discussed, and the characteristics of dielectric barrier discharge(DBD) in non-uniform electric field are studied. It makes sure that APGD in air is formed by DBD in alternating current electric field with using the absorbing electron capacity of electret materials to provide initial electrons and to end the discharge progress. Through designing electric field to form two-dimensional space varying electric field and three-dimensional space varying electric field, the development of electron avalanches in airgap is suppressed effectively and a large space of APGD plasma in air is generated. Further,through combining electrode structures, a large area of APGD plasma in air is generated. On the other hand, by using the method of increasing the density of initial electrons, millimeter-gap glow discharge in atmospheric pressure air is formed, and a maximum gap distance between electrodes is 8 mm. By using the APGD plasma surface treatment device composed of contact electrodes, the surface modification of high polymer materials such as aramid fiber and polyester are studied and good effect of modifications is obtained. The present paper provides references for the researchers of industrial applications of plasma.展开更多
In order to form an atmospheric-pressure plasma jet without airflow, a needle–ring electrode structure is proposed in this paper. When heteropolar potentials are applied to a needle and a ring, a marked electric fiel...In order to form an atmospheric-pressure plasma jet without airflow, a needle–ring electrode structure is proposed in this paper. When heteropolar potentials are applied to a needle and a ring, a marked electric field strength enhancement around the needle’s pointed end has been found. When the same potential is applied to both the needle and the ring, the lateral electric field strength for the needle can be weakened. By using the above two methods, an increase of the difference between the pointed end electric field strength and the lateral one is achieved and stable plasma jets are formed. A symmetrical space electric field distribution is established at the pointed end of the needles when several sets of heteropolar needle–ring electrodes are uniformly arranged, which is conducive to forming a uniform array plasma jet. Under DC discharge conditions, a safe and stable plasma jet of high density and an array plasma jet are successfully achieved.展开更多
<div style="text-align:justify;"> Electric field superposition principle and Gauss’s law are the basis of electrostatics. By extended analysis on the electric field lines of a charge, it is shown that...<div style="text-align:justify;"> Electric field superposition principle and Gauss’s law are the basis of electrostatics. By extended analysis on the electric field lines of a charge, it is shown that electric field superposition principle and Gauss’s law are not tenable in some states, involving the electric field of ion atmosphere that is a key concept in Debye-Hückel theory of electrolyte solution and plasma. Unveiling Debye shield, ion atmosphere (Debye spherical layer 1) actually is equivalent to continue to transmit the electric field originated from the central ion, just changing the direction of the electric field. Debye spherical layer 2 and multiple Debye spherical layers generate in the transmission. Due to the effect of the multiple Debye spherical layers of charged particles in the universe, gravitation originates from electric force. </div>展开更多
文摘A new probe for atmospheric electric field mill is introduced.It consists of three parts:signal acquisition circuit for atmospheric electric field,preamplifier circuit and phase sensitive detection circuit.The signal acquisition circuit adopts the double-stator structure to form differential input circuit,thus double-precision is obtained.Preamplifier circuit is made of current-to-voltage (I-V) conversion circuit,differential amplifier circtuit and secondary amplifying circuit.The polarity of electric field is obtained via phase sensitive detection circuit.Simulation results are obtained using Multisim,and the feasibility of the designed probe is verified.
基金Supported by the National Basic Research Program of China(2011CB811404)the Natural Science Foundation of China(40774081)+1 种基金the Specialized Research Fund for State Key LaboratoriesCAS-NSSC-135 project
文摘High-energy electron precipitation in the high latitude regions enhances the ionization of the atmosphere,and subsequently increases the atmospheric conductivities and the vertical electric field of the atmosphere near the ground as well.The High-Energy Electron Flux(HEEF) data measured by the Fengyun-3 meteorological satellite are analyzed together with the data of nearsurface atmospheric vertical electric field measured at the Russian Vostok Station.Three HEEF enhancements are identified and it is shown that when the HEEF increases to a certain level,the local atmospheric vertical electric field near the ground can increase substantially than usual.The response time of the electric field to HEEF enhancement is about 3.7 to 4 days.
基金the National Key RESEARCH and Development Program of the Ministry of Science and Technology‘Life Prediction and Operation Risk Assessment of UHV Equipment under long-term Service conditions(No.2017YFB0902705)’for supporting this workthe No.703 Research Institute of CSIC(China Shipbuilding Industry Corporation)Yunnan Electric Test&Research Institute Group CO.,Ltd for assistance in this paper.
文摘In this paper, an improved air discharge fluid model under non-uniform electric field is constructed based on the plasma module COMSOL Multiphysics with artificial stability term, and the boundary conditions developed in the previous paper are applied to the calculation of photoionization rate. Based on the modified model, the characteristics of low temperature subatmospheric air discharge under 13 kV direct current voltage are discussed, including needle-plate and needle-needle electrode structures. Firstly, in order to verify the reliability of the model, a numerical example and an experimental verification were carried out for the modified model respectively. Both verification results show that the model can ensure the accuracy and repeatability of the calculation. Secondly, according to the calculation results of the modified model, under the same voltage and spacing, the reduced electric field under low temperature subatmosphere pressure is larger than that under normal temperature and atmospheric pressure. The high electric field leads to the air discharge at low temperature and sub atmospheric pressure entering the streamer initiation stage earlier, and has a faster propagation speed in the streamer development stage, which shortens the overall discharge time. Finally, the discharge characteristics of the two electrode structures are compared, and it is found that the biggest difference between them is that there is a pre-ionization region near the cathode in the needle-needle electrode structure. When the pre-ionization level reaches 1013 cm-3, the propagation speed of the positive streamer remains unchanged throughout the discharge process, and is no longer affected by the negative streamer. The peak value of electric field decreases with the increase of pre-ionization level, and tends to be constant during streamer propagation. Based on the previous paper, this paper constructs the air discharge model under non-uniform electric field, complements with the previous paper, and forms a relatively complete set of air discharge simulation system under low temperature and sub atmospheric pressure, which provides a certain reference for future research.
基金This work is supported by the National Key Research and Development Program of China(Grant No.2021YFE0105500)the National Natural Science Foundation of China(Grant No.61671248)+2 种基金the Key Research and Development Plan of Jiangsu Province,China(Grant No.BE2018719)Postgraduate Research and Practice Innovation Program of Jiangsu Province(Grant No.SJCX19_0309)the Advantage Discipline Information and Communication Engineering of Jiangsu Province,China.
文摘Data loss or distortion causes adverse effects on the accuracy and stability of the thunderstorm point charge localization.To solve this problem,we propose a data complementary method based on the atmospheric electric field apparatus array group.The electric field component measurement model of the atmospheric electric field apparatus is established,and the orientation parameters of the thunderstorm point charge are defined.Based on the mirror method,the thunderstorm point charge coordinates are obtained by using the potential distribution formulas.To test the validity of the basic algorithm,the electric field component measurement error and the localization accuracy are studied.Besides the azimuth angle and the elevation angle,the localization parameters also include the distance from the apparatus to the thunderstorm cloud.Based on a primary electric field apparatus,we establish the array group of apparatuses.Based on this,the data measured by each apparatus is complementarily processed to regain the thunderstorm point charge position.The results show that,compared with the radar map data,this method can accurately reflect the location of the thunderstorm point charge,and has a better localization effect.Additionally,several observation results during thunderstorm weather have been presented.
文摘In this work,the effects of the methane gas flow and the internal oscillating electric field between electrodes on radio-frequency(RF)atmospheric pressure argon/methane plasma jet and process of diamond-like carbon(DLC)film deposition have been investigated.Properties of RF atmospheric Ar/methane plasma jet such as active species density,length,electron temperature,appearance and ionization process of argon/methane plasma jet are changed due to the changing of methane flow content and electric field vector and its gradient.With increasing methane flow,the formation of C2 hydrocarbon and CH band content is decreased because injected electrical energy to a mixture of Ar/methane gases is insufficient to stabilize the ionization process of methane gas and the electrical-chemical reaction rate is decreased.With shortening the gas gap between two electrodes,electric field strength and its gradient are increased leading to more energy injection to the electron.Electrical-chemical reactions are strengthened leading to increasing the CH band content.These phenomena introduce the Ar/methane plasma jet in different modes causing to deposit the DLC film with different structures and properties.With using quartz glass and alumina ceramic as dielectric barriers tubes,RF atmospheric pressure Ar/methane plasma jet has been used to deposit DLC coating in different modes.Increasing methane content and shortening the gas gap leads to decreasing sp3 bonded content and the quality of the deposited film.
文摘The paper presents research data on positive and negative coronas inatmospheric pressure air in a highly inhomogeneous electric field. Thedata show that irrespective of the polarity of pointed electrodes placed ina high electric field (200 kV/cm), this type of discharge develops via ballstreamers even if the gap voltage rises slowly (0.2 kV/ms). The start voltageof first positive streamers, compared to negative ones, is higher andthe amplitude and the frequency of their current pulses are much lower:about two times and more than two orders of magnitude, respectively.The higher frequency of current pulses from negative streamers provideshigher average currents and larger luminous areas of negative coronascompared to positive ones. Positive and negative cylindrical streamersfrom a pointed to a plane electrode are detected and successive dischargetransitions at both polarities are identified.
基金supported by the National Natural Science Foundation of China ( Grant No. 61072133 )the Production,Learning and Research Joint Innovation Program of Jiangsu Province, China ( Grant Nos. BY2013007-02, SBY201120033)+2 种基金the Major Project Plan for Natural science Research in Colleges and Universities of Jiangsu Province, China( Grant No. 15KJA460008)the Open Topic of Atmospheric Sounding Key Open Laboratory of China Meteorological Administration ( Grant No. KLAS201407)the advantage discipline platform " Information and Communication Engineering" of Jiangsu Province,China
文摘This article proposes the hybrid method to inverse the equivalent electric charge of thunder cloud based on the data of multi-station atmospheric electric field. Firstly,the method combines the genetic algorithm( GA) and New ton method through the mosaic hybrid structure. In addition,the thunder cloud equivalent charge is inversed based on the forw ard modeling results by giving the parameters of the thunder cloud charge structure. Then an ideal model is built to examine the performance compared to the nonlinear least squares method. Finally,a typical thunderstorms process in Nanjing is analyzed by Genetic-New ton algorithm with the help of weather radar. The results show the proposed method has the strong global searching capability so that the problem of initial value selection can be solved effectively,as well as gets the better inversion results. Furthermore,the mosaic hybrid structure can absorb the advantages of tw o algorithms better,and the inversion position is consistent with the strongest radar echo.The inversion results find the upper negative charge is small and can be ignored,w hich means the triple-polarity charge structure is relatively scientific,w hich could give some references to the research like lightning forecasting,location tracking.
文摘The long time practice of observational research on earthquake prediction has shown that the information on shortterm and imminent earthquake precursors can hardly be detected, but it is very important for practical and effective earthquake prediction. The result of analysis and study in this paper has shown that the anomaly of quasi static atmospheric electric field may be a kind of reliable information on short term and imminent earthquake precursors.On such a basis, the 20 years′ continuous and reliable data of atmospheric electric field observed at the Baijiatuan seismic station are used to study the correlation between the anomalies in seismic activity and relative quiet periods bear on the occurrence of near earthquakes within 200 km range around Beijing after the Tangshan earthquake. The observational results recently reported before hand in written form and earthquakes that actually occurred in near field in corresponding time periods are compared and analyzed. The efficacy of these written prediction opinions about near earthquakes in the recent 10 years is tested. From the test results, the brilliant prospect that the anomaly of quasi static atmospheric electric field may really become a reliable mark for making short term and imminent earthquake predictions is discussed. Besides, as a preliminary step, some judgment indexes for predicting earthquakes by use of the observational data of atmospheric electric field before earthquakes are put forward. In the last part, it is pointed out that it would be possible to obtain more believable judgment indexes for determining the three elements of near earthquakes before greater earthquakes ( M S5) only if a relatively reasonable station network (2~4 stations every 10 000 km 2) is deployed and further investigation is made.
文摘[Objective] The research aimed to analyze characteristics of atmospheric electric field in polluted area. [Method] By using data of atmospheric electric field meter in Taiyuan in 2009, daily and annual changes of atmospheric electric field in Taiyuan were analyzed. [ Result] Atmospheric electric field intensity in Taiyuan was higher than that in other areas. Daily change was double-peak double-valley type. The first highest value appeared at nightfall, and the second highest value was before the noon. The first lowest value appeared in early morning, while the second low- est value appeared after the noon. Annual change was single-peak single-valley type. The maximum appeared in winter, while the minimum ap- peared in summer. [ Conclusion] When forecasting thunderstorm, in the area with higher aerosol content, alarm threshold of electric field should be adjusted via comparison with actual observation, which had very strong regional characteristics. By analyzing real-time monitoring data of atmospheric electric field, thunderstorm forecast could be realized, and timeliness and accuracy of warning and forecast could be increased.
基金Supported by General Project of Jiangxi Meteorological Bureau in 2018(201818)
文摘Based on ground observation,lightning locator and atmospheric electric field instrument data,the characteristics of lightning and atmospheric electric field in Nanchang County were analyzed. The warning effect of the atmospheric electric field instruments on lightning was studied,and the threshold of some atmospheric electric field instruments was adjusted according to the expectation of the warning accuracy rate. In Nanchang County,the annual number of thunderstorm days averaged 48. 6. Lightning mainly occurred from March to August,with a maximum of 8. 8 d in August. The lightning areas were mainly concentrated in the south,followed by the north,and the frequency of lightning in the middle was relatively low. The diurnal variation of lightning was obvious,and lightning happened most frequently from afternoon to evening. Five atmospheric electric field instruments were set up according to the lightning areas of Nanchang County. The average electric field intensity on a sunny day was 0. 06,0. 05,0. 16,0. 07,and 0. 17 kV/m respectively,with certain seasonal variations. The field intensity in June was the lowest in the whole year. The atmospheric electric field on a sunny day also had obvious diurnal variation characteristics,generally presenting the characteristics of double peaks and double valleys. The first peak of atmospheric electric field intensity appeared one hour later than that of relative humidity,and then the change trends were relatively consistent. After the adjustment,the warning accuracy rate of the atmospheric electric field instruments was greatly improved to meet the expectation.
基金National Natural Science Foundation of China (No.10120130794)
文摘From April 1st to August 14th, 2006, thunderstorms had been recorded at Yangbajing Cosmic Ray Observatory by ARGO-YBJ experiment. This paper analyzed the correlation between atmospheric electric field (AEF) and "scaler mode" counting rate during thunderstorm. Counting rates of multiplicities n=1,2 were found to have a large increase (from 1.02% to 9.03%), while there was few or no changes in those of multiplicities n=3 and n≥4 during the thunderstorms. The counts of different multiplicities had different feedbacks on the violent change of AEF, which showed that their energy and most components were distinguishing.
文摘The association between the lunar phases and the atmospheric electric field has been investigated from the superposed epoch analysis of the long series of continuous data of the vertical electric field for Colaba, Bombay (18 ° 53'N, 73 ° 48'E 11 mASL) for the period 1947-1966. Also the periodicities in the atmospheric electric field have been studied from the spectral analysis of the data. The study has indicated that when the full moon is within 4 of the ecliptic plane i.e.,Bf 4 ° , the electric field peaks on the day of the full moon followed by a steep fall in the field values up to 4 days following the full moon day and there after it showed a steep increase. Also, the electric field has exhibited 5-9 day periodicity and its multiples are nearly always present. The periodicity in the electric field corresponds with the average time interval between the successive magnetic sector boundary (MSB ) crossings i.e., 7 days. On most of the occasions, the MSB crossing day is associated with a maximum of one or more of the wavelengths derived from the spectral analysis of the atmospheric electric field.
文摘The variations noticed in the atmospheric electric field recorded at Pune (18°32'N, 73°51'E, 559 m ASL), a tropical inland station located in Dcccan Plateau, India, during the period 1930-1987, have been examined in relation to the variations observed in the Angstrom turbidity coefficient (β) and selected meteorological parameters. The monthly and annual mean values of the atmospheric electric field. Angstrom turbidity coefficient (β), rainfall, temperature and relative humidity for the years 1930-1938, 1957-1958, 1964-1965, 1973-1974 and 1987 were considered in the study.The results of the above study indicated gradual increases in the atmospheric electric field over the period of study (1930-1987) which is statistically significant at less than 5%level. The increases noticed during different periods varied from 30 to 109%. The increase noticed during the period (1930-1938) and (1973-1974) was maximum (109%). The Angstrom turbidity coefficient also showed systematic increases during the period of study, which is consistent. The diurnal curve of the atmospheric electric field at the station by and large, showed a double oscillation, which is generally observed in the conlinental environments.
基金Supported by the National High Technology Research and Development Program of China(863 Program,2011AA-040405)the National Natural Science Foundation of China(Nos.61101049,61201078,61302032,61327810)
文摘This paper presents a high performance electric field micro sensor with combined differential structure.The sensor consists of two backward laid micro-machined chips,each packaged by polymer and metal.The novel combined differential structure effectively reduces various environmental affections,such as thermal drift,humidity drift and electrostatic charge accumulation.The sensor is tested in near-ground place as well as balloon-borne sounding.In different weather conditions,the measurement results showed good agreement with those of the commercial electric field mill.
基金National Key Research and Development Program of China(No.2021YFE0114700)National Natural Science Foundation of China(Nos.52130701 and 51977096)。
文摘Electric field is an important parameter of plasma,which is related to electron temperature,electron density,excited species density,and so on.In this work,the electric field of an atmospheric pressure plasma jet is diagnosed by the electric field induced second harmonic(E-FISH)method,and the time-resolved electric field under different conditions is investigated.When positive pulse voltage is applied,the electric field has a peak of about 25 kV cm-1at the rising edge of the voltage pulse.A dark channel is left behind the plasma bullet and the electric field in the dark channel is about 5 kV cm-1.On the other hand,when negative pulse voltage is applied,the electric field has a peak of-16 kV cm-1when the negative voltage is increased to-8 kV.A relatively bright channel is left behind the plasma head and the electric field in this relatively bright channel is about-6 kV cm-1.When the pulse rising time increases from 60 to 200 ns,the peak electric field at both the rising edge and the falling edge of the voltage decreases significantly.When 0.5%of oxygen is added to the main working gas helium,the peak electric field at the rising edge is only about 15 kV cm-1.On the other hand,when 0.5%nitrogen is added,the peak electric field increases especially at the falling edge of the voltage pulse,where it increases reversely from-12 to-16 kV cm-1(the minus sign only represents the direction of electric field).
基金Project supported by Russian Foundation for Basic Research (12-08-91150-GFEN_a), National Natural Science Foundation of China (51222701, 51207154, 51211120183), National Basic Research Program of China (973 Program) (20llCB209402), Opening Project of State Key Laboratory of Electrical Insulation and Power Equipment in Xi'an Jiaotong University (EIPEI2204), Chinese Academy of Sciences Visiting Professorship for Senior International Scientists (2012TtG0021).
文摘A pulse generator with a voltage rise time of~1.5 ns and voltage amplitude variable from 30 kV to 200 kV was designed for generating runaway electron beams in atmospheric pressure air with different interelectrode gaps.The influence of the voltage amplitude and gap length on the generation was studied.In the gas diode geometry under study,the gap voltage at which the generation of a runaway electron beam begins was determined.Decreasing the voltage pulse amplitude does not increase the beam current pulse width measured with a time resolution of~0.1 ns.It is shown that the escape of beam electrons to the downstream of the foil is sync in time with the voltage drop across the gap,and that the delay of beam current generation increases gradually from 1.1 ns to 2.6 ns as the voltage pulse amplitude across the gap decreases from~100 kV to 40 kV.
基金Supported by the Application of the Forecasting Warning System for Lightning Disaster in Yunan Plateau(YNKJXM20190733)National Natural Science Foundation of China(41775006).
文摘In this paper we have extended the semi-analytical model presented by Yashunin et al.to compute both of the lightning vertical and horizontal electric field considering the effect of nonlinear atmospheric electric parameters,and validate its accuracy by using our 2-D FDTD method.It is noted that the semi-analytical model can predict not only the lightning vertical field,but also the horizontal electric field with a satisfied accuracy in a small region with a radius ranging from 5 to 30 km at a height from 80 to 90 km above the lightning strike point.Compared with the results in the free space with a vacuum,the conducting altitude atmosphere has a relatively little effect on the radiated field component,but it has much effect on the electrostatic and induction component because their duration times are longer than the local relaxation time.For example,the induction field component in the conducting nonlinear medium decreases by about 43%,compared with that in the free space with a vacuum.The induction field is larger than the radiation field component within a radius of 25 km at a height of 80 km above the lightning strike point.Therefore,although the induction component may be likely one extra energy source(except for the radiation field)for creating the pancake shape of some elves with a luminous central part,we have to take into account the effect of nonlinear atmospheric electric parameters on the prediction of induced field component peak value that is needed for the production of elves.
文摘Atmospheric pressure glow discharge(APGD) plasma in air has high application value. In this paper, the methods of generating APGD plasma in air are discussed, and the characteristics of dielectric barrier discharge(DBD) in non-uniform electric field are studied. It makes sure that APGD in air is formed by DBD in alternating current electric field with using the absorbing electron capacity of electret materials to provide initial electrons and to end the discharge progress. Through designing electric field to form two-dimensional space varying electric field and three-dimensional space varying electric field, the development of electron avalanches in airgap is suppressed effectively and a large space of APGD plasma in air is generated. Further,through combining electrode structures, a large area of APGD plasma in air is generated. On the other hand, by using the method of increasing the density of initial electrons, millimeter-gap glow discharge in atmospheric pressure air is formed, and a maximum gap distance between electrodes is 8 mm. By using the APGD plasma surface treatment device composed of contact electrodes, the surface modification of high polymer materials such as aramid fiber and polyester are studied and good effect of modifications is obtained. The present paper provides references for the researchers of industrial applications of plasma.
基金supported by National Natural Science Foundation of China (No. 51577011)
文摘In order to form an atmospheric-pressure plasma jet without airflow, a needle–ring electrode structure is proposed in this paper. When heteropolar potentials are applied to a needle and a ring, a marked electric field strength enhancement around the needle’s pointed end has been found. When the same potential is applied to both the needle and the ring, the lateral electric field strength for the needle can be weakened. By using the above two methods, an increase of the difference between the pointed end electric field strength and the lateral one is achieved and stable plasma jets are formed. A symmetrical space electric field distribution is established at the pointed end of the needles when several sets of heteropolar needle–ring electrodes are uniformly arranged, which is conducive to forming a uniform array plasma jet. Under DC discharge conditions, a safe and stable plasma jet of high density and an array plasma jet are successfully achieved.
文摘<div style="text-align:justify;"> Electric field superposition principle and Gauss’s law are the basis of electrostatics. By extended analysis on the electric field lines of a charge, it is shown that electric field superposition principle and Gauss’s law are not tenable in some states, involving the electric field of ion atmosphere that is a key concept in Debye-Hückel theory of electrolyte solution and plasma. Unveiling Debye shield, ion atmosphere (Debye spherical layer 1) actually is equivalent to continue to transmit the electric field originated from the central ion, just changing the direction of the electric field. Debye spherical layer 2 and multiple Debye spherical layers generate in the transmission. Due to the effect of the multiple Debye spherical layers of charged particles in the universe, gravitation originates from electric force. </div>