Experimental beneficiation processes of quartz concentrate in arc plasma torches of two different types and electric powers were studied. An emission scanning electron microscope and a universal laser analyzer were us...Experimental beneficiation processes of quartz concentrate in arc plasma torches of two different types and electric powers were studied. An emission scanning electron microscope and a universal laser analyzer were used to investigate the structures as well as the size distributions of grains and microparticles. Inductively coupled plasma–mass spectrometry was used to determine the chemical compositions of nonstructural solid-phase mineral impurities in quartz concentrate. Results related to the modified grains' structure and size distribution, the compositions of impurities, and the gas–liquid inclusions in the quartz concentrate were investigated. The total impurities concentrations in the processed grains were found to satisfy the IOTA-STD standard(industry standard for grading high quality fused quartz products). The optimal condition(i.e., the optimal specific plasma enthalpy) for the production of high-purity quartz in arc plasma torches was found to depend on the geological-genetic type and the structural and textural features(i.e., chemical composition and gas–liquid inclusions) of the quartz concentrate.展开更多
Thrust-vectoring capability has become a critical feature for propulsion systems as space missions move from static to dynamic.Thrust-vectoring is a well-developed area of rocket engine science.For electric propulsion...Thrust-vectoring capability has become a critical feature for propulsion systems as space missions move from static to dynamic.Thrust-vectoring is a well-developed area of rocket engine science.For electric propulsion,however,it is an evolving field that has taken a new leap forward in recent years.A review and analysis of thrust-vectoring schemes for electric propulsion systems have been conducted.The scope of this review includes thrust-vectoring schemes that can be implemented for electrostatic,electromagnetic,and beam-driven thrusters.A classification of electric propulsion schemes that provide thrust-vectoring capability is developed.More attention is given to schemes implemented in laboratory prototypes and flight models.The final part is devoted to a discussion on the suitability of different electric propulsion systems with thrust-vectoring capability for modern space mission operations.The thrust-vectoring capability of electric propulsion is necessary for inner and outer space satellites,which are at a disadvantage with conventional unidirectional propulsion systems due to their limited maneuverability.展开更多
文摘Experimental beneficiation processes of quartz concentrate in arc plasma torches of two different types and electric powers were studied. An emission scanning electron microscope and a universal laser analyzer were used to investigate the structures as well as the size distributions of grains and microparticles. Inductively coupled plasma–mass spectrometry was used to determine the chemical compositions of nonstructural solid-phase mineral impurities in quartz concentrate. Results related to the modified grains' structure and size distribution, the compositions of impurities, and the gas–liquid inclusions in the quartz concentrate were investigated. The total impurities concentrations in the processed grains were found to satisfy the IOTA-STD standard(industry standard for grading high quality fused quartz products). The optimal condition(i.e., the optimal specific plasma enthalpy) for the production of high-purity quartz in arc plasma torches was found to depend on the geological-genetic type and the structural and textural features(i.e., chemical composition and gas–liquid inclusions) of the quartz concentrate.
基金performed at large-scale research facility"Beam-M"of Bauman Moscow State Technical University following the government task by the Ministry of Science and Higher Education of the Russian Federation(No.FSFN-2024-0007).
文摘Thrust-vectoring capability has become a critical feature for propulsion systems as space missions move from static to dynamic.Thrust-vectoring is a well-developed area of rocket engine science.For electric propulsion,however,it is an evolving field that has taken a new leap forward in recent years.A review and analysis of thrust-vectoring schemes for electric propulsion systems have been conducted.The scope of this review includes thrust-vectoring schemes that can be implemented for electrostatic,electromagnetic,and beam-driven thrusters.A classification of electric propulsion schemes that provide thrust-vectoring capability is developed.More attention is given to schemes implemented in laboratory prototypes and flight models.The final part is devoted to a discussion on the suitability of different electric propulsion systems with thrust-vectoring capability for modern space mission operations.The thrust-vectoring capability of electric propulsion is necessary for inner and outer space satellites,which are at a disadvantage with conventional unidirectional propulsion systems due to their limited maneuverability.
