This study uses Baidu News data and introduces a novel proxy for the rate of information flow to examine its relationship with return volatility in Chinese commodity futures and to test two competing hypotheses.We exa...This study uses Baidu News data and introduces a novel proxy for the rate of information flow to examine its relationship with return volatility in Chinese commodity futures and to test two competing hypotheses.We examine the contemporaneous relationships using correlation coefficient analysis,and find apparent differences between the information flow-return volatility relationship and the information flowtrading volume relationship.The empirical evidence contradicts the mixture of distribution hypothesis(MDH)and suggests that the rate of information flow distinctly affects trading volume and volatility.We conducted linear and nonlinear Granger causality tests to explore the sequential information arrival hypothesis(SIAH).The empirical results prove that a lead-lag linear and nonlinear causality exists between the information flow and return volatility of commodity futures,which is consistent with SIAH.In other words,a partial equilibrium exists before reaching the ultimate equilibrium when the new information arrives in the market.Finally,these findings are robust to alternative measurement of return volatility and subperiod analysis.Our findings reject the MDH and support the SIAH in the context of Chinese commodity futures.展开更多
Capacitive deionization(CDI)is a novel electrochemical water-treatment technology.The electrode material is an important factor in determining the ion separation efficiency.Activated carbon(AC)is extensively used as a...Capacitive deionization(CDI)is a novel electrochemical water-treatment technology.The electrode material is an important factor in determining the ion separation efficiency.Activated carbon(AC)is extensively used as an electrode material;however,there are still many deficiencies in commercial AC.We adopted a simple processing method,ball milling,to produce ball milled AC(BAC)to improve the physical and electrochemical properties of the original AC and desalination efficiency.The BAC was characterized in detail and used for membrane capacitive deionization(MCDI)and flow-electrode capacitive deionization(FCDI)electrode materials.After ball milling,the BAC obtained excellent pore structures and favorable surfaces for ion adsorption,which reduced electron transfer resistance and ion migration resistance in the electrodes.The optimal ball-milling time was 10 h.However,the improved effects of BAC as fixed electrodes and flow electrodes are different and the related mechanisms are discussed in detail.The average salt adsorption rates(ASAR)of FCDI and MCDI were improved by 134%and 17%,respectively,and the energy-normalized removal salt(ENRS)were enhanced by 21%and 53%,respectively.We believe that simple,low-cost,and environmentally friendly BAC has great potential for practical engineering applications of FCDI and MCDI.展开更多
Membrane capacitive deionization(MCDI)is an efficient desalination technology for brine.Penicillin fermentation residue biochar(PFRB)possesses a hierarchical porous and O/N-doped structure which could serve as a high-...Membrane capacitive deionization(MCDI)is an efficient desalination technology for brine.Penicillin fermentation residue biochar(PFRB)possesses a hierarchical porous and O/N-doped structure which could serve as a high-capacity desalination electrode in the MCDI system.Under optimal conditions(electrode weight,voltage,and concentration)and a carbonization temperature of 700℃,the maximum salt adsorption capacity of the electrode can reach 26.4 mg/g,which is higher than that of most carbon electrodes.Furthermore,the electrochemical properties of the PFRB electrode were characterized through cyclic voltammetry(CV)and electrochemical impedance spectroscopy(EIS)with a maximum specific capacitance of 212.18 F/g.Finally,biotoxicity tests have showed that PFRB was non-biotoxin against luminescent bacteria and the MCDI system with the PFRB electrode remained stable even after 27 adsorption–desorption cycles.This study provides a novel way to recycle penicillin residue and an electrode that can achieve excellent desalination.展开更多
Flow-electrode capacitive deionization(FCDI)is an innovative technology in which an intermediate chamber plays an important role in the desalination process.However,relatively few studies have been conducted on the st...Flow-electrode capacitive deionization(FCDI)is an innovative technology in which an intermediate chamber plays an important role in the desalination process.However,relatively few studies have been conducted on the structures of these intermediate chambers.In this study,we propose a novel flow-electrode capacitive deionization device with a spindle-shaped inlet chamber(S-FCDI).The desalination rate of the S-FCDI under optimal operating conditions was 36%higher than that of the FCDI device with a conventional rectangular chamber(R-FCDI).The spindle-shaped chamber transferred 1.2μmol more ions than the rectangular chamber,based on energy per joule.Additionally,we performed a detailed analysis of different inlet chamber shapes using computational fluid dynamics software.We concluded that S-FCDI has a relatively low flow resistance and almost no stagnation zone.This provides unique insights into the development of intermediate chambers.This study may contribute to the improvement of the desalination performance in industrial applications of FCDI.展开更多
基金supported by the National Social Science Fund of China(24CGL027)the National Natural Science Foundation of China(72101009,72141304,72201122)National Key Research and Development Program of China(2022YFC3303304).
文摘This study uses Baidu News data and introduces a novel proxy for the rate of information flow to examine its relationship with return volatility in Chinese commodity futures and to test two competing hypotheses.We examine the contemporaneous relationships using correlation coefficient analysis,and find apparent differences between the information flow-return volatility relationship and the information flowtrading volume relationship.The empirical evidence contradicts the mixture of distribution hypothesis(MDH)and suggests that the rate of information flow distinctly affects trading volume and volatility.We conducted linear and nonlinear Granger causality tests to explore the sequential information arrival hypothesis(SIAH).The empirical results prove that a lead-lag linear and nonlinear causality exists between the information flow and return volatility of commodity futures,which is consistent with SIAH.In other words,a partial equilibrium exists before reaching the ultimate equilibrium when the new information arrives in the market.Finally,these findings are robust to alternative measurement of return volatility and subperiod analysis.Our findings reject the MDH and support the SIAH in the context of Chinese commodity futures.
基金supported by the Science and Technology Project of Hebei Education Department(No.QN2022038)the State Key Joint Laboratory of Environment Simulation and Pollution Control(No.22K05ESPCT)the Hebei University of Science and Technology Graduate Innovation Funding Program(No.XJCXZZSS2022009).
文摘Capacitive deionization(CDI)is a novel electrochemical water-treatment technology.The electrode material is an important factor in determining the ion separation efficiency.Activated carbon(AC)is extensively used as an electrode material;however,there are still many deficiencies in commercial AC.We adopted a simple processing method,ball milling,to produce ball milled AC(BAC)to improve the physical and electrochemical properties of the original AC and desalination efficiency.The BAC was characterized in detail and used for membrane capacitive deionization(MCDI)and flow-electrode capacitive deionization(FCDI)electrode materials.After ball milling,the BAC obtained excellent pore structures and favorable surfaces for ion adsorption,which reduced electron transfer resistance and ion migration resistance in the electrodes.The optimal ball-milling time was 10 h.However,the improved effects of BAC as fixed electrodes and flow electrodes are different and the related mechanisms are discussed in detail.The average salt adsorption rates(ASAR)of FCDI and MCDI were improved by 134%and 17%,respectively,and the energy-normalized removal salt(ENRS)were enhanced by 21%and 53%,respectively.We believe that simple,low-cost,and environmentally friendly BAC has great potential for practical engineering applications of FCDI and MCDI.
基金This work was supported by the Natural Science Foundation of Hebei Province(China)(Nos.B2021208035,B2020208064,and E2020208054).
文摘Membrane capacitive deionization(MCDI)is an efficient desalination technology for brine.Penicillin fermentation residue biochar(PFRB)possesses a hierarchical porous and O/N-doped structure which could serve as a high-capacity desalination electrode in the MCDI system.Under optimal conditions(electrode weight,voltage,and concentration)and a carbonization temperature of 700℃,the maximum salt adsorption capacity of the electrode can reach 26.4 mg/g,which is higher than that of most carbon electrodes.Furthermore,the electrochemical properties of the PFRB electrode were characterized through cyclic voltammetry(CV)and electrochemical impedance spectroscopy(EIS)with a maximum specific capacitance of 212.18 F/g.Finally,biotoxicity tests have showed that PFRB was non-biotoxin against luminescent bacteria and the MCDI system with the PFRB electrode remained stable even after 27 adsorption–desorption cycles.This study provides a novel way to recycle penicillin residue and an electrode that can achieve excellent desalination.
基金Science and Technology Project of Hebei Education Department(China)(No.QN2022038)special fund of State Key Joint Laboratory of Environment Simulation and Pollution Control(China)(No.22K05ESPCT)。
文摘Flow-electrode capacitive deionization(FCDI)is an innovative technology in which an intermediate chamber plays an important role in the desalination process.However,relatively few studies have been conducted on the structures of these intermediate chambers.In this study,we propose a novel flow-electrode capacitive deionization device with a spindle-shaped inlet chamber(S-FCDI).The desalination rate of the S-FCDI under optimal operating conditions was 36%higher than that of the FCDI device with a conventional rectangular chamber(R-FCDI).The spindle-shaped chamber transferred 1.2μmol more ions than the rectangular chamber,based on energy per joule.Additionally,we performed a detailed analysis of different inlet chamber shapes using computational fluid dynamics software.We concluded that S-FCDI has a relatively low flow resistance and almost no stagnation zone.This provides unique insights into the development of intermediate chambers.This study may contribute to the improvement of the desalination performance in industrial applications of FCDI.
