The utilization of coal fly ash derived from circulating fluidized bed combustion(CFBFA)still faces great challenges because of its unique characteristics.In this study,a zeolitic material with Na-P1 zeolite as the ma...The utilization of coal fly ash derived from circulating fluidized bed combustion(CFBFA)still faces great challenges because of its unique characteristics.In this study,a zeolitic material with Na-P1 zeolite as the main phase was successfully synthesized via a hydrothermal method by using CFBFA as the raw material.The effects of hydrothermal temperature,time,and added CTAB amount on the characterizations of synthesized materials were investigated by XRD,SEM,and XPS.The properties of the optimal zeolitic material and its adsorption performance for Pb^(2+)in aqueous solution were evaluated.The influences of pH,initial concentration,dosage,and temperature on Pb^(2+)adsorption were also examined.Results revealed the following optimal parameters for the synthesis of zeolitic material:NaOH concentration of 2 mol·L^(-1),solid-to-liquid ratio of 1:10 g·ml^(-1),hydrothermal temperature of 110℃,hydrothermal time of 9 h,and CTAB amount of 1 g(per 100 ml solution).The adsorption capacities of the zeolitic material reached 329.67,424.69,and 542.22 mg·g^(-1) when the pH values of aqueous solution were 5,6,and 7,respectively.The Pb^(2+)removal efficiency can reach more than 99%in aqueous solution with the initial concentrations of 100-300 mg·L^(-1) under pH 6 and suitable adsorbent dosage.The adsorption and kinetics of Pb^(2+)on the zeolitic material can be described by Langmuir isotherm and pseudo-second-order kinetic models,respectively.The ion exchange between Pb^(2+)and Na^(+)and chemisorption are the main adsorption mechanism.All these findings imply that the synthesis of low-cost adsorbent for Pb^(2+)removal from weak acid and neutral aqueous solution provides a highly effective method to utilize CFBFA.展开更多
Bio-asphalt has a great application prospect in the replacement of petroleum-based asphalt to pave and maintain asphalt pavement. However, the problems of flow-induced crystallization and phase separation caused by fl...Bio-asphalt has a great application prospect in the replacement of petroleum-based asphalt to pave and maintain asphalt pavement. However, the problems of flow-induced crystallization and phase separation caused by flowinduced crystallization had severely restricted its application. This paper describes the progress of research on preparation, property evaluation and phase separation mechanism of bio-asphalt. The advantages and disadvantages of preparation methods of bio-asphalt are states. The fundamental physical and rheological properties of bio-asphalt are investigated, especially for flow-induced crystallization. There exists obvious flow-induced crystallization because bio-asphalt is rich in waxes that crystallize easily. Owing to the existence of excess biochar,bio-asphalt appears phase separation. A brief review of the effect of bio-oil and biochar on asphalt volatile organic compounds(VOCs) is presented. Research find that bio-oil/biochar are not only replenish the light components of asphalt, but also improve the flow-induced crystallization and phase separation of bio-asphalt. There exists synergistic effect of biochar and bio-oil in asphalt modification. Moreover, biochar can improve the durability of bio-oil modified asphalt, but excessive addition of biochar to bio-oil modified asphalt can cause phase separation.Adding an appropriate amount of bio-oil and biochar to asphalt can improve its high-temperature resistance, lowtemperature crack resistance, and system compatibility.展开更多
In microwave communication systems,focusing and imaging have attracted widespread attention due to their application prospects in the information processing and communication fields.Most existing multi-channel focusin...In microwave communication systems,focusing and imaging have attracted widespread attention due to their application prospects in the information processing and communication fields.Most existing multi-channel focusing and imaging are implemented by interleaved metasurfaces.However,the disadvantages of their large size and low efficiency limit their practical applications in large-capacity and low-loss integrated systems.To solve these issues,here,we propose a non-interleaved polarization-frequency multiplexing metasurface for high-efficiency multi-channel focusing and imaging.The meta-atoms of the non-interleaved metasurface are composed of a metallic ground plate,two dielectric layers,a larger cross-shaped metal structure,and a smaller cross-shaped metal structure embedded by a circular metal aperture.By altering the size of two cross-shaped structures,the designed meta-atom can obtain the independent complete 2π phase coverage with high reflection efficiency at two different frequency ranges for two orthogonal linear polarization(LP)incidences,realizing polarization multiplexing and frequency multiplexing.Moreover,two types of metasurfaces based on the above meta-atoms are designed to realize multi-channel focusing and imaging with high efficiency.As a proof,the focusing metasurface is fabricated and measured,and the measured results are well consistent with simulated results.Therefore,the proposed scheme has the advantages of high efficiency,multi-channel,and compact size,which possesses broad application prospects in low-loss and multichannel communication integrated systems.展开更多
The multidimensional dynamic manipulation of spoof surface waves(SSWs)is crucial for terahertz(THz)on-chip integrated systems.However,existing metasurfaces are limited to passive,single-function wavefront shaping of S...The multidimensional dynamic manipulation of spoof surface waves(SSWs)is crucial for terahertz(THz)on-chip integrated systems.However,existing metasurfaces are limited to passive,single-function wavefront shaping of SSWs,which precludes on-chip multidimensional dynamic control and hinders their practical applications.To address these limitations,we propose a polarization multiplexing THz graphene metasurface.展开更多
基金supported by National Natural Science Foundation of China(22078181,U1810205)the Bidding Project of Shanxi Province(20191101007).
文摘The utilization of coal fly ash derived from circulating fluidized bed combustion(CFBFA)still faces great challenges because of its unique characteristics.In this study,a zeolitic material with Na-P1 zeolite as the main phase was successfully synthesized via a hydrothermal method by using CFBFA as the raw material.The effects of hydrothermal temperature,time,and added CTAB amount on the characterizations of synthesized materials were investigated by XRD,SEM,and XPS.The properties of the optimal zeolitic material and its adsorption performance for Pb^(2+)in aqueous solution were evaluated.The influences of pH,initial concentration,dosage,and temperature on Pb^(2+)adsorption were also examined.Results revealed the following optimal parameters for the synthesis of zeolitic material:NaOH concentration of 2 mol·L^(-1),solid-to-liquid ratio of 1:10 g·ml^(-1),hydrothermal temperature of 110℃,hydrothermal time of 9 h,and CTAB amount of 1 g(per 100 ml solution).The adsorption capacities of the zeolitic material reached 329.67,424.69,and 542.22 mg·g^(-1) when the pH values of aqueous solution were 5,6,and 7,respectively.The Pb^(2+)removal efficiency can reach more than 99%in aqueous solution with the initial concentrations of 100-300 mg·L^(-1) under pH 6 and suitable adsorbent dosage.The adsorption and kinetics of Pb^(2+)on the zeolitic material can be described by Langmuir isotherm and pseudo-second-order kinetic models,respectively.The ion exchange between Pb^(2+)and Na^(+)and chemisorption are the main adsorption mechanism.All these findings imply that the synthesis of low-cost adsorbent for Pb^(2+)removal from weak acid and neutral aqueous solution provides a highly effective method to utilize CFBFA.
基金supported by the National Natural Science Foundation of China (No. 52378456, No. W2421062, No. 52008235)the Special Foundation of Achievements Transformation Guide of Department of Science and Technology of Shanxi Province (No. 202204021301075, No.201804D131034)+1 种基金the Patent Transformation Project of Shanxi Province(No. 202306009)Shanxi Graduate Education Innovation Plan(2024SJ027)。
文摘Bio-asphalt has a great application prospect in the replacement of petroleum-based asphalt to pave and maintain asphalt pavement. However, the problems of flow-induced crystallization and phase separation caused by flowinduced crystallization had severely restricted its application. This paper describes the progress of research on preparation, property evaluation and phase separation mechanism of bio-asphalt. The advantages and disadvantages of preparation methods of bio-asphalt are states. The fundamental physical and rheological properties of bio-asphalt are investigated, especially for flow-induced crystallization. There exists obvious flow-induced crystallization because bio-asphalt is rich in waxes that crystallize easily. Owing to the existence of excess biochar,bio-asphalt appears phase separation. A brief review of the effect of bio-oil and biochar on asphalt volatile organic compounds(VOCs) is presented. Research find that bio-oil/biochar are not only replenish the light components of asphalt, but also improve the flow-induced crystallization and phase separation of bio-asphalt. There exists synergistic effect of biochar and bio-oil in asphalt modification. Moreover, biochar can improve the durability of bio-oil modified asphalt, but excessive addition of biochar to bio-oil modified asphalt can cause phase separation.Adding an appropriate amount of bio-oil and biochar to asphalt can improve its high-temperature resistance, lowtemperature crack resistance, and system compatibility.
基金National Natural Science Foundation of China(62075052,6227419)National Key Research and Development Program of China(2024YFE0108300)+2 种基金Science and Technology Major Project of Guangxi,China(Gui Ke AA21077015,Gui Ke AA24263032)Science Foundation of the National Key Laboratory of Science and Technology on Advanced Composites in Special Environments(JCKYS2020603C009,6142905212711)Project of Innovative and Entrepreneurship Training Program for College Students in Heilongjiang Province(201810214105)。
文摘In microwave communication systems,focusing and imaging have attracted widespread attention due to their application prospects in the information processing and communication fields.Most existing multi-channel focusing and imaging are implemented by interleaved metasurfaces.However,the disadvantages of their large size and low efficiency limit their practical applications in large-capacity and low-loss integrated systems.To solve these issues,here,we propose a non-interleaved polarization-frequency multiplexing metasurface for high-efficiency multi-channel focusing and imaging.The meta-atoms of the non-interleaved metasurface are composed of a metallic ground plate,two dielectric layers,a larger cross-shaped metal structure,and a smaller cross-shaped metal structure embedded by a circular metal aperture.By altering the size of two cross-shaped structures,the designed meta-atom can obtain the independent complete 2π phase coverage with high reflection efficiency at two different frequency ranges for two orthogonal linear polarization(LP)incidences,realizing polarization multiplexing and frequency multiplexing.Moreover,two types of metasurfaces based on the above meta-atoms are designed to realize multi-channel focusing and imaging with high efficiency.As a proof,the focusing metasurface is fabricated and measured,and the measured results are well consistent with simulated results.Therefore,the proposed scheme has the advantages of high efficiency,multi-channel,and compact size,which possesses broad application prospects in low-loss and multichannel communication integrated systems.
基金National Key Research and Development Program of China(2024YFE0108300,2023YFB3210400)Science and Technology Major Projects of Guangxi(Gui Ke AA24263032,Gui Ke AA21077015)+3 种基金Open Fund Project of Key Laboratory of Integrated Circuits and Microsystems in Guangxi Universities(ICM-25-02)National Natural Science Foundation of China(62075052,6227419)Science Foundation of the National Key Laboratory of Science and Technology on Advanced Composites in Special Environments(JCKYS2020603C009,6142905212711)Project of Innovative and Entrepreneurship Training Program for College Students in Heilongjiang Province(201810214105)。
文摘The multidimensional dynamic manipulation of spoof surface waves(SSWs)is crucial for terahertz(THz)on-chip integrated systems.However,existing metasurfaces are limited to passive,single-function wavefront shaping of SSWs,which precludes on-chip multidimensional dynamic control and hinders their practical applications.To address these limitations,we propose a polarization multiplexing THz graphene metasurface.
