SF_(6) has excellent insulation performance and arc extinguishing ability,and is widely used in the power industry.However,its global warming potential is about 23,500 times that of C0_(2),it can exist stably in the a...SF_(6) has excellent insulation performance and arc extinguishing ability,and is widely used in the power industry.However,its global warming potential is about 23,500 times that of C0_(2),it can exist stably in the atmosphere,it is not easily degradable and is of great potential harm to the environment.Based on pulsed dielectric barrier discharge plasma technology,the effects of H_(2)O and 0_(2) on the degradation of SF_(6) were studied.Studies have shown that H_(2)O can effectively promote the decomposition of SF_(6) and improve its degradation rate and energy efficiency of degradation.Under the action of a pulse input voltage and input frequency of 15 kV and 15 kHz,respectively,when H_(2)O is added alone the effect of 1% H_(2)O is the best,and the rate and energy efficiency of degradation of SF_(6) reach their maximum values,which are 91.9% and 8.25 g kWh^(-1),respectively.The synergistic effect of H_(2)O and O_(2) on the degradation of SF_(6) was similar to that of H_(2)O.When the concentration of H_(2)O and O_(2) was 1%,the system obtained the best rate and energy efficiency of degradation,namely 89.7% and 8.05 g kWh~(-1),respectively.At the same time,different external gases exhibit different capabilities to regulate decomposition products.The addition of H_(2)O can effectively improve the selectivity of S0_(2).Under the synergistic effect of H_(2)O and O_(2),with increase in O_(2) concentration the degradation products gradually transformed into SO_(2)F_(2).From the perspective of harmless treatment of the degradation products of SF_(6),the addition of O_(2) during the SF_(6) degradation process should be avoided.展开更多
With the growing demand of oil worldwide,heavy oil has increasingly become vital in the world energy market.However,further development of heavy oil reservoirs are limited by regular enhanced oil recovery(EOR)methods....With the growing demand of oil worldwide,heavy oil has increasingly become vital in the world energy market.However,further development of heavy oil reservoirs are limited by regular enhanced oil recovery(EOR)methods.In situ upgrading technology provides potential for the development of heavy oil and bitumen reservoirs.This study reviews three categories of in situ upgrading methods:solvent-based,in situ combustion(ISC),and catalytic.Solvent-based methods,including cyclic solvent injection,vapor extraction,and hybrid processes,have recently received attention and have been progressed in both laboratory and field applications.However,high solvent costs in relation to the low price of heavy oil have continued to limit the field applications of these techniques.ISC,which may have the potential to develop particularly harsh reservoirs with extremely viscous crude oil,involves complex reaction mechanisms and consists of three main steps:oxidation,combustion,and gas flooding.Yet,complex operating conditions and a low success rate have restricted its application.Catalytic methods,which have demonstrated the potential to refine and upgrade crude oil in a more economic and environmentally friendly way,are often accompanied by conventional thermal EOR methods,such as steam flooding and ISC,and involve a series of hydroprocessing or hydrotreating reactions,such as hydrocracking,hydrodesulfurization,hydrodenitrogenation,hydrodeoxygenation,and hydrodemetallization.However,the high cost and complexity of the reaction mechanisms have limited their applications.展开更多
新蝎蛉属Neopanorpa van der Weele,1909是典型的东洋区昆虫类群,在中国西南地区有着最高的多样性。本文描述新蝎蛉属2新种:棒状新蝎蛉Neopanorpa leptorhapis sp.nov.采自云南,弯月新蝎蛉Neopanorpa lunulivalva sp.nov.采自广西。Neop...新蝎蛉属Neopanorpa van der Weele,1909是典型的东洋区昆虫类群,在中国西南地区有着最高的多样性。本文描述新蝎蛉属2新种:棒状新蝎蛉Neopanorpa leptorhapis sp.nov.采自云南,弯月新蝎蛉Neopanorpa lunulivalva sp.nov.采自广西。Neopanorpa lindsleyi Bicha,2015原始记载于越南,本文首次报导于广西。展开更多
基金supported by Guizhou Province (Ceneral), grant/award number Qian Ke He Zhi Cheng [2022] General 207, National Natural Science Foundation of China (No. 52307170)Natural Science Foundation of Hubei Province, China (No. 2023AFB382)。
文摘SF_(6) has excellent insulation performance and arc extinguishing ability,and is widely used in the power industry.However,its global warming potential is about 23,500 times that of C0_(2),it can exist stably in the atmosphere,it is not easily degradable and is of great potential harm to the environment.Based on pulsed dielectric barrier discharge plasma technology,the effects of H_(2)O and 0_(2) on the degradation of SF_(6) were studied.Studies have shown that H_(2)O can effectively promote the decomposition of SF_(6) and improve its degradation rate and energy efficiency of degradation.Under the action of a pulse input voltage and input frequency of 15 kV and 15 kHz,respectively,when H_(2)O is added alone the effect of 1% H_(2)O is the best,and the rate and energy efficiency of degradation of SF_(6) reach their maximum values,which are 91.9% and 8.25 g kWh^(-1),respectively.The synergistic effect of H_(2)O and O_(2) on the degradation of SF_(6) was similar to that of H_(2)O.When the concentration of H_(2)O and O_(2) was 1%,the system obtained the best rate and energy efficiency of degradation,namely 89.7% and 8.05 g kWh~(-1),respectively.At the same time,different external gases exhibit different capabilities to regulate decomposition products.The addition of H_(2)O can effectively improve the selectivity of S0_(2).Under the synergistic effect of H_(2)O and O_(2),with increase in O_(2) concentration the degradation products gradually transformed into SO_(2)F_(2).From the perspective of harmless treatment of the degradation products of SF_(6),the addition of O_(2) during the SF_(6) degradation process should be avoided.
基金This work was supported by the National Natural Science Foundation of China(Grant No:51704245)Petro China Inno-vation Foundation(2019D-5007-0212).
文摘With the growing demand of oil worldwide,heavy oil has increasingly become vital in the world energy market.However,further development of heavy oil reservoirs are limited by regular enhanced oil recovery(EOR)methods.In situ upgrading technology provides potential for the development of heavy oil and bitumen reservoirs.This study reviews three categories of in situ upgrading methods:solvent-based,in situ combustion(ISC),and catalytic.Solvent-based methods,including cyclic solvent injection,vapor extraction,and hybrid processes,have recently received attention and have been progressed in both laboratory and field applications.However,high solvent costs in relation to the low price of heavy oil have continued to limit the field applications of these techniques.ISC,which may have the potential to develop particularly harsh reservoirs with extremely viscous crude oil,involves complex reaction mechanisms and consists of three main steps:oxidation,combustion,and gas flooding.Yet,complex operating conditions and a low success rate have restricted its application.Catalytic methods,which have demonstrated the potential to refine and upgrade crude oil in a more economic and environmentally friendly way,are often accompanied by conventional thermal EOR methods,such as steam flooding and ISC,and involve a series of hydroprocessing or hydrotreating reactions,such as hydrocracking,hydrodesulfurization,hydrodenitrogenation,hydrodeoxygenation,and hydrodemetallization.However,the high cost and complexity of the reaction mechanisms have limited their applications.
基金supported by the National Natural Science Foundation of China (31872278,31672341)。
文摘新蝎蛉属Neopanorpa van der Weele,1909是典型的东洋区昆虫类群,在中国西南地区有着最高的多样性。本文描述新蝎蛉属2新种:棒状新蝎蛉Neopanorpa leptorhapis sp.nov.采自云南,弯月新蝎蛉Neopanorpa lunulivalva sp.nov.采自广西。Neopanorpa lindsleyi Bicha,2015原始记载于越南,本文首次报导于广西。