Dimmers are very widely applied in theatres,cinemas,dancing-parties, auditoriums and signal systems.They are usually supplied by single-stage AC/AC converters in the past with voltage regulation technique with the dis...Dimmers are very widely applied in theatres,cinemas,dancing-parties, auditoriums and signal systems.They are usually supplied by single-stage AC/AC converters in the past with voltage regulation technique with the disadvantages of high total harmonic distortion,low power factor and poor power transfer efficiency.This paper introduces a novel method-DC-modulation that implements DC/DC conversion technology into AC/AC converters.The DC-modulated single-stage PFC AC/AC converters effectively improved the power factor up to 0.999 and the power transfer efficiency up to 97.8 %.The experimental results verified our design and calculation.This technique will be widely used in light dimming and other industrial applications.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
Breakdown of atmospheric pressure air gaps with combined design of the cathode at the voltage pulse rise rate equal to 1014V/s has been studied with picoseconds’temporal resolution.Cathode assembly has a structure co...Breakdown of atmospheric pressure air gaps with combined design of the cathode at the voltage pulse rise rate equal to 1014V/s has been studied with picoseconds’temporal resolution.Cathode assembly has a structure consisting of a flat thin foil and a grid of parallel foil thin wires.In the space behind the cathode foil a fast electron flow was recorded.The current value of the fast electron beam recorded behind the cathode is essentially influenced by the anode material.At a grid cathode and flat anode,the spectra of fast electrons generated both in direct(towards the anode)and reverse directions have been reconstructed by the attenuation curves.展开更多
The paper proposes an experimental method of material inspection,which is based on digital processing of multi-frequency eddy current measurement data.The influences of various factors(conductivity,the gap between the...The paper proposes an experimental method of material inspection,which is based on digital processing of multi-frequency eddy current measurement data.The influences of various factors(conductivity,the gap between the sample surface and the sensor,the thickness of the sample) on the obtained hodographs are examined by taking the aluminum alloys for example,and the possibility of separation of various factors is analyzed.The results obtained are indicative of how much promise the proposed method offers for the inspection and testing of products made of aluminum alloys.展开更多
We suppose that in order to maintain high accuracy of holes and to lower residual stresses after cold expansion of thick-walled cylinders, which undergo cross-section plastic deformation, it is necessary to perform ax...We suppose that in order to maintain high accuracy of holes and to lower residual stresses after cold expansion of thick-walled cylinders, which undergo cross-section plastic deformation, it is necessary to perform axial plastic compression and subsequent cold expansion with small interferences. To test this hypothesis, we studied hoop, radial and axial residual stresses in cylinders made of carbon steel AISI 1050 with hole diameter of 5 mm, outer diameter of 15 mm and length of 30 mm by Sachs method as well as accuracy of expanded holes. It is found that double cold expansion with total interference equal to 5.1% generates hoop residual stresses with largest absolute value equal to 284 MPa and ensures high holes accuracy(IT7). After plastic compression with strain equal to 0.5 and 1% the mentioned stresses reduced to 120 and 75 MPa respectively,and accuracy of the holes reduced as well. Subsequent cold expansion with small interference equal to 0.9% helps to restore holes accuracy(IT7)gained by double cold expansion and ensure that absolute value of hoop residual stresses(177 MPa) is lower compared to double cold expansion.展开更多
Nazimskaya oil zone is situated in Khanty-Mansiysk autonomous district.It covers two oil fields: Srednenazimskoe and Galyanovskoe,and has rather wide stratigraphical range of oil content(Paleozoic -lower Cretaceous de...Nazimskaya oil zone is situated in Khanty-Mansiysk autonomous district.It covers two oil fields: Srednenazimskoe and Galyanovskoe,and has rather wide stratigraphical range of oil content(Paleozoic -lower Cretaceous deposits).However,it is suggested that the widespread Bazhenovo-Upper Abalak oil subcomplex(upper Jurassic) in Nazimskaya oil zone is the most perspective object.Current goal of research is to identify zones of superior展开更多
The examination of macroelements and natural radionuclides in the bottom sediments of small lakes and soils in the catchment areas of the Baikal region allows for the study of the mechanism of inflow and the source of...The examination of macroelements and natural radionuclides in the bottom sediments of small lakes and soils in the catchment areas of the Baikal region allows for the study of the mechanism of inflow and the source of these materials.On the basis of the results of rentgenostructural analysis lake sediments are divided into four types:terrigenous,carbonate, terrigenous-carbonate and organogenic.Through the analysis of gamma-ray spectrometry and ato-展开更多
Zones of combustion metamorphism(CM)are frequently associated with oil fields and adjacent bituminous marine sediments.A typical example is the Mottled Zone(MZ)complexes located within carbonate strata at the western ...Zones of combustion metamorphism(CM)are frequently associated with oil fields and adjacent bituminous marine sediments.A typical example is the Mottled Zone(MZ)complexes located within carbonate strata at the western margin of the Arabian petroleum province(Israel,Jordan).Being localized upon the eroded surface of Upper Cretaceous stratum, the MZ complexes are composed of brecciated sediments of the underlying Cretaceous sequence uplifted from depths of at least 1.5 km.They展开更多
There are many serious problems of the industrial wastewater cleaning in the mining and enriching industry caused by their great volumes.The current works are devoted to investigating actions of the natural and artifi...There are many serious problems of the industrial wastewater cleaning in the mining and enriching industry caused by their great volumes.The current works are devoted to investigating actions of the natural and artificial geochemical barriers to decrease toxic drainage waters from the sulphide-containing tailings.Belovs Zinc Plant(Kemerovo region,Russian Federation) tailing and natural(not modified) bentonitic clay from Kamalinskoe deposit(Krasno-展开更多
文摘Dimmers are very widely applied in theatres,cinemas,dancing-parties, auditoriums and signal systems.They are usually supplied by single-stage AC/AC converters in the past with voltage regulation technique with the disadvantages of high total harmonic distortion,low power factor and poor power transfer efficiency.This paper introduces a novel method-DC-modulation that implements DC/DC conversion technology into AC/AC converters.The DC-modulated single-stage PFC AC/AC converters effectively improved the power factor up to 0.999 and the power transfer efficiency up to 97.8 %.The experimental results verified our design and calculation.This technique will be widely used in light dimming and other industrial applications.
基金Supported by the Ministry of Science and Technological Development of the Republic Serbia and“Super-Intense Laser-Matter Interactions”-SILMI Project,European Scientific Foundation
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Project supported by Russian Foundation for Basic Research(12-08-00081_a,12-08-00105-a)
文摘Breakdown of atmospheric pressure air gaps with combined design of the cathode at the voltage pulse rise rate equal to 1014V/s has been studied with picoseconds’temporal resolution.Cathode assembly has a structure consisting of a flat thin foil and a grid of parallel foil thin wires.In the space behind the cathode foil a fast electron flow was recorded.The current value of the fast electron beam recorded behind the cathode is essentially influenced by the anode material.At a grid cathode and flat anode,the spectra of fast electrons generated both in direct(towards the anode)and reverse directions have been reconstructed by the attenuation curves.
基金supported by Program for Basic Scientific Research of the State Academies of Sciences for 2013e2020the RF Ministry of Education and Science (Contract No. 02.G25.31.0063)
文摘The paper proposes an experimental method of material inspection,which is based on digital processing of multi-frequency eddy current measurement data.The influences of various factors(conductivity,the gap between the sample surface and the sensor,the thickness of the sample) on the obtained hodographs are examined by taking the aluminum alloys for example,and the possibility of separation of various factors is analyzed.The results obtained are indicative of how much promise the proposed method offers for the inspection and testing of products made of aluminum alloys.
基金Lyudmila Petrova for invaluable metrological support. A.I.D. also thanks RFBR grant no. 15-08-01511a
文摘We suppose that in order to maintain high accuracy of holes and to lower residual stresses after cold expansion of thick-walled cylinders, which undergo cross-section plastic deformation, it is necessary to perform axial plastic compression and subsequent cold expansion with small interferences. To test this hypothesis, we studied hoop, radial and axial residual stresses in cylinders made of carbon steel AISI 1050 with hole diameter of 5 mm, outer diameter of 15 mm and length of 30 mm by Sachs method as well as accuracy of expanded holes. It is found that double cold expansion with total interference equal to 5.1% generates hoop residual stresses with largest absolute value equal to 284 MPa and ensures high holes accuracy(IT7). After plastic compression with strain equal to 0.5 and 1% the mentioned stresses reduced to 120 and 75 MPa respectively,and accuracy of the holes reduced as well. Subsequent cold expansion with small interference equal to 0.9% helps to restore holes accuracy(IT7)gained by double cold expansion and ensure that absolute value of hoop residual stresses(177 MPa) is lower compared to double cold expansion.
文摘Nazimskaya oil zone is situated in Khanty-Mansiysk autonomous district.It covers two oil fields: Srednenazimskoe and Galyanovskoe,and has rather wide stratigraphical range of oil content(Paleozoic -lower Cretaceous deposits).However,it is suggested that the widespread Bazhenovo-Upper Abalak oil subcomplex(upper Jurassic) in Nazimskaya oil zone is the most perspective object.Current goal of research is to identify zones of superior
文摘The examination of macroelements and natural radionuclides in the bottom sediments of small lakes and soils in the catchment areas of the Baikal region allows for the study of the mechanism of inflow and the source of these materials.On the basis of the results of rentgenostructural analysis lake sediments are divided into four types:terrigenous,carbonate, terrigenous-carbonate and organogenic.Through the analysis of gamma-ray spectrometry and ato-
文摘Zones of combustion metamorphism(CM)are frequently associated with oil fields and adjacent bituminous marine sediments.A typical example is the Mottled Zone(MZ)complexes located within carbonate strata at the western margin of the Arabian petroleum province(Israel,Jordan).Being localized upon the eroded surface of Upper Cretaceous stratum, the MZ complexes are composed of brecciated sediments of the underlying Cretaceous sequence uplifted from depths of at least 1.5 km.They
文摘There are many serious problems of the industrial wastewater cleaning in the mining and enriching industry caused by their great volumes.The current works are devoted to investigating actions of the natural and artificial geochemical barriers to decrease toxic drainage waters from the sulphide-containing tailings.Belovs Zinc Plant(Kemerovo region,Russian Federation) tailing and natural(not modified) bentonitic clay from Kamalinskoe deposit(Krasno-
