Exploding foil initiator(EFI)is a kind of advanced device for initiating explosives,but its function is unstable when it comes to directly igniting pyrotechnics.To solve the problem,this research aims to reveal the ig...Exploding foil initiator(EFI)is a kind of advanced device for initiating explosives,but its function is unstable when it comes to directly igniting pyrotechnics.To solve the problem,this research aims to reveal the ignition mechanism of EFIs directly igniting pyrotechnics.An oscilloscope,a photon Doppler velocimetry,and a plasma spectrum measurement system were employed to obtain information of electric characteristics,impact pressure,and plasma temperature.The results of the electric characteristics and the impact pressure were inconsistent with ignition results.The only thing that the ignition success tests had in common was that their plasma all had a relatively long period of high-temperature duration(HTD).It eventually concludes that the ignition mechanism in this research is the microconvection heat transfer rather than the shock initiation,which differs from that of exploding foil initiators detonating explosives.Furthermore,the methods for evaluating the ignition success of semiconductor bridge initiators are not entirely applicable to the tests mentioned in this paper.The HTD is the critical parameter for judging the ignition success,and it is influenced by two factors:the late time discharge and the energy of the electric explosion.The longer time of the late time discharge and the more energy of the electric explosion,the easier it is to expand the HTD,which improves the probability of the ignition success.展开更多
In order to provide reference for high quality tobacco producion,this experiment adopted a randomized block design in a field plot,and analyzed the effects of boron fertilizer on the growth,development on comprehensiv...In order to provide reference for high quality tobacco producion,this experiment adopted a randomized block design in a field plot,and analyzed the effects of boron fertilizer on the growth,development on comprehensive quality of flue-cured tobacco by using mathematical statistics methods such as multiple comparison with NC297 as test material.The results showed that:spraying boron fertilizer on flue-cured tobacco leaves can promote the growth of flue-cured tobacco NC297 to a certain extent,effectively reduce the total particulate matter and tar content of tobacco,and play a positive role in regulating the total sugar,reducing sugar,nicotine and potassium content of flue-cured tobacco;the comprehensive quality of NC297 was the best when boron was applied at medium potassium level(K2B1).展开更多
Brine extremely rich in potassium,boron and bromine has been discovered from the Middle Triassic Leikoupo Formation at a depth of 4300 m in Sichuan Province.It contains-50g/L of K^+,>92g/L of Na^+,>12g/L of B2O3...Brine extremely rich in potassium,boron and bromine has been discovered from the Middle Triassic Leikoupo Formation at a depth of 4300 m in Sichuan Province.It contains-50g/L of K^+,>92g/L of Na^+,>12g/L of B2O3,>2.36g/L of Br^- and -0.030g/L of I^+.The solid precipitates during evaporation at 25℃ include KB5O8·4H2O,K2B4O7·3H2O,MgCl2·6H2O and KMgCl3·6H2O.The brine ranges from 2.2‰,to2.8‰(SMOW)inδ^18O,-38‰-53‰(SMOW)in δD,15.6‰inδ^34S,and 13.5‰-15.1‰inδ^11B.These data,particularly the isotopic composition of boron,indicate that the brine has a composite derivation from marine and nonmarine brines and dissolved marine evaporites in the Triassic system.展开更多
文摘Exploding foil initiator(EFI)is a kind of advanced device for initiating explosives,but its function is unstable when it comes to directly igniting pyrotechnics.To solve the problem,this research aims to reveal the ignition mechanism of EFIs directly igniting pyrotechnics.An oscilloscope,a photon Doppler velocimetry,and a plasma spectrum measurement system were employed to obtain information of electric characteristics,impact pressure,and plasma temperature.The results of the electric characteristics and the impact pressure were inconsistent with ignition results.The only thing that the ignition success tests had in common was that their plasma all had a relatively long period of high-temperature duration(HTD).It eventually concludes that the ignition mechanism in this research is the microconvection heat transfer rather than the shock initiation,which differs from that of exploding foil initiators detonating explosives.Furthermore,the methods for evaluating the ignition success of semiconductor bridge initiators are not entirely applicable to the tests mentioned in this paper.The HTD is the critical parameter for judging the ignition success,and it is influenced by two factors:the late time discharge and the energy of the electric explosion.The longer time of the late time discharge and the more energy of the electric explosion,the easier it is to expand the HTD,which improves the probability of the ignition success.
文摘In order to provide reference for high quality tobacco producion,this experiment adopted a randomized block design in a field plot,and analyzed the effects of boron fertilizer on the growth,development on comprehensive quality of flue-cured tobacco by using mathematical statistics methods such as multiple comparison with NC297 as test material.The results showed that:spraying boron fertilizer on flue-cured tobacco leaves can promote the growth of flue-cured tobacco NC297 to a certain extent,effectively reduce the total particulate matter and tar content of tobacco,and play a positive role in regulating the total sugar,reducing sugar,nicotine and potassium content of flue-cured tobacco;the comprehensive quality of NC297 was the best when boron was applied at medium potassium level(K2B1).
文摘Brine extremely rich in potassium,boron and bromine has been discovered from the Middle Triassic Leikoupo Formation at a depth of 4300 m in Sichuan Province.It contains-50g/L of K^+,>92g/L of Na^+,>12g/L of B2O3,>2.36g/L of Br^- and -0.030g/L of I^+.The solid precipitates during evaporation at 25℃ include KB5O8·4H2O,K2B4O7·3H2O,MgCl2·6H2O and KMgCl3·6H2O.The brine ranges from 2.2‰,to2.8‰(SMOW)inδ^18O,-38‰-53‰(SMOW)in δD,15.6‰inδ^34S,and 13.5‰-15.1‰inδ^11B.These data,particularly the isotopic composition of boron,indicate that the brine has a composite derivation from marine and nonmarine brines and dissolved marine evaporites in the Triassic system.
