The microstructure and mechanical properties of the compact strip production(CSP)processed quenching and partitioning(Q&P)steels were investigated through experimental methods to address the challenge of designing...The microstructure and mechanical properties of the compact strip production(CSP)processed quenching and partitioning(Q&P)steels were investigated through experimental methods to address the challenge of designing high-performance Q&P steels.Compared with the conventional process(CP)produced samples,with slightly reduced strength,the total elongation of the CSP produced samples was increased by nearly 7%.Microstructural analysis revealed that variations in austenite stability were not the primary cause for the differences in mechanical properties between the CSP and the CP.The CSP processed Q&P steel exhibited milder center segregation behavior in contrast to the CP processed Q&P steel.Consequently,in the CSP processed Q&P steel,a higher proportion of austenite and a lower proportion of martensite were observed at the center position,delaying the crack initiation in the central region and contributing to the enhanced ductility.The investigation into the CSP process reveals its effect on alleviation of segregation and enhancement of mechanical properties of the Q&P steel.展开更多
Coal fly ash(FA),a valuable industrial solid residue generated from coal combustion,is composed of various metal oxides and has a high thermal stability.Given that the coal-based energy will continue to account for a ...Coal fly ash(FA),a valuable industrial solid residue generated from coal combustion,is composed of various metal oxides and has a high thermal stability.Given that the coal-based energy will continue to account for a significant portion of global electricity generation in the coming years,the lack of effective management strategies exacerbates the threat of FA wastes to the surrounding environment and human health.For a sustainable development,green and renewable hydrogen economy and CO_(2)capture efforts provide appealing opportunities to valorize FA as catalysts and/or sorbents due to their appealing physicochemical properties.Hydrogen applications along with carbon neutrality are potential strategies to mitigate climate change crisis,but high processing costs(catalysts/sorbents)are challenging to realize this purpose.In this context,the utilization of FA not only enhances industrial competitiveness(by reducing manufacturing costs),but also provides ecologically friendly approaches to minimizing this solid waste.This state-of-the-art review highlights a wide-ranging outlook on the valorization of FA as catalysts and sorbents for hydrogen-rich gas production via conventional/intensified processes(CO_(2)/H_(2)O reforming,ammonia decomposition,hydride hydrolysis).The fundamental physicochemical characterizations and hazards/utilization of FA,which significantly affect the FA's utilization in various fields,are first introduced.The influence of several factors(like FA types and catalysis/sorption operation conditions)on the activity performance of FA-based materials is then discussed in detail.This critical review aims to open the window to further innovative ideas regarding the application of different FA residues in other catalytic and sorption processes.展开更多
PSN-PZN-PZT + x wt. %Cr2O3, X = 0.0-0-9, were prepared by conventional mixed oxide techniques at sintering temperatures of 1220 degrees C-1300 degrees C for 2 h. The effect of sintering temperature on the microstructu...PSN-PZN-PZT + x wt. %Cr2O3, X = 0.0-0-9, were prepared by conventional mixed oxide techniques at sintering temperatures of 1220 degrees C-1300 degrees C for 2 h. The effect of sintering temperature on the microstructure and the piezoelectric properties was investigated by XRD, SEM, and other conventional measurement. The result indicated that with temperature increasing, the valence of Cr ion from Cr5+ or Cr6+ changes into C3+, and the piezoelectric properties turn hard. With increasing Cr2O3 content, the amount of rhombohedral phases increases and the morphotropic boundary phase is correspondingly shifts to rhombohedral phase. A uniform microstructure and excellent comprehensive properties were obtained at 1240 degrees C as the amount of Cr2O3 is 0.5 wt.%.展开更多
Transient electronics,which can be controllably broken down with zero environmental impact,hold significant potential in implantable devices,hardware security,and disposable sensors.While miniaturization is essential ...Transient electronics,which can be controllably broken down with zero environmental impact,hold significant potential in implantable devices,hardware security,and disposable sensors.While miniaturization is essential for enhancing device performance,increasing integration density,and enabling new applications,degradable materials often face challenges with conventional microfabrication processes like lithography due to their sensitivity to heat and solvents.In this paper,we present a UV photodetector(PD)with micro-scale patterning,fabricated using a novel solvent-free material patterning method.The PD,consisting of molybdenum(Mo)as the electrode,zinc oxide(ZnO)as the photoactive material,and polyvinyl alcohol(PVA)as the substrate,can be dissolved in deionized(DI)water,leaving behind non-toxic byproducts.The device exhibits high responsivity over 50 A/W and an obvious response to varying sunlight intensities,demonstrating its potential for temporary,eco-friendly UV sensing applications.Additionally,we demonstrated that the photoresist used in the solvent-free material patterning method can be reused for subsequent fabrication while maintaining good registration,enhancing efficiency and reducing material waste.This approach provides a scalable and high-efficiency microfabrication strategy for integrating functional materials into unconventional platforms,offering broader applicability in next-generation transient,biodegradable,and flexible sensor technologies.展开更多
The N2O production in two nitrogen removal processes treating domestic wastewater was investigated in laboratory-scale aerobic-anoxic sequencing batch reactors （SBRs）. Results showed that N2O emission happened in th...The N2O production in two nitrogen removal processes treating domestic wastewater was investigated in laboratory-scale aerobic-anoxic sequencing batch reactors （SBRs）. Results showed that N2O emission happened in the aerobic phase rather than in the anoxic phase. During the aerobic phase, the nitrogen conversion to N2O gas was 27.7% and 36.8% of NH＋-N loss for conventional biologic N-removal process and short-cut biologic N-removal process. The dissolved N2O was reduced to N2 in the anoxic denitrification phase. The N2O production rate increased with the increasing of nitrite concentration and ceased when NH＋-N oxidation was terminated. Higher nitrite accumulation resulted in higher NEO emission in the short-cut nitrogen removal process. Pulse-wise addition of 20 mg NO2 -N. L- 1 gave rise to 3-fold of N2O emission in the conventional N-removal process, while little change happened with 20 mg NOS-N L-1 was added to SBR1.展开更多
基金support from the National Key R&D Program of China(No.2021YFB3702403).
文摘The microstructure and mechanical properties of the compact strip production(CSP)processed quenching and partitioning(Q&P)steels were investigated through experimental methods to address the challenge of designing high-performance Q&P steels.Compared with the conventional process(CP)produced samples,with slightly reduced strength,the total elongation of the CSP produced samples was increased by nearly 7%.Microstructural analysis revealed that variations in austenite stability were not the primary cause for the differences in mechanical properties between the CSP and the CP.The CSP processed Q&P steel exhibited milder center segregation behavior in contrast to the CP processed Q&P steel.Consequently,in the CSP processed Q&P steel,a higher proportion of austenite and a lower proportion of martensite were observed at the center position,delaying the crack initiation in the central region and contributing to the enhanced ductility.The investigation into the CSP process reveals its effect on alleviation of segregation and enhancement of mechanical properties of the Q&P steel.
基金supported by the Natural Sciences and Engineering Research Council of Canada(NSERC)the China Scholarship Council(CSC,201708130079)。
文摘Coal fly ash(FA),a valuable industrial solid residue generated from coal combustion,is composed of various metal oxides and has a high thermal stability.Given that the coal-based energy will continue to account for a significant portion of global electricity generation in the coming years,the lack of effective management strategies exacerbates the threat of FA wastes to the surrounding environment and human health.For a sustainable development,green and renewable hydrogen economy and CO_(2)capture efforts provide appealing opportunities to valorize FA as catalysts and/or sorbents due to their appealing physicochemical properties.Hydrogen applications along with carbon neutrality are potential strategies to mitigate climate change crisis,but high processing costs(catalysts/sorbents)are challenging to realize this purpose.In this context,the utilization of FA not only enhances industrial competitiveness(by reducing manufacturing costs),but also provides ecologically friendly approaches to minimizing this solid waste.This state-of-the-art review highlights a wide-ranging outlook on the valorization of FA as catalysts and sorbents for hydrogen-rich gas production via conventional/intensified processes(CO_(2)/H_(2)O reforming,ammonia decomposition,hydride hydrolysis).The fundamental physicochemical characterizations and hazards/utilization of FA,which significantly affect the FA's utilization in various fields,are first introduced.The influence of several factors(like FA types and catalysis/sorption operation conditions)on the activity performance of FA-based materials is then discussed in detail.This critical review aims to open the window to further innovative ideas regarding the application of different FA residues in other catalytic and sorption processes.
文摘PSN-PZN-PZT + x wt. %Cr2O3, X = 0.0-0-9, were prepared by conventional mixed oxide techniques at sintering temperatures of 1220 degrees C-1300 degrees C for 2 h. The effect of sintering temperature on the microstructure and the piezoelectric properties was investigated by XRD, SEM, and other conventional measurement. The result indicated that with temperature increasing, the valence of Cr ion from Cr5+ or Cr6+ changes into C3+, and the piezoelectric properties turn hard. With increasing Cr2O3 content, the amount of rhombohedral phases increases and the morphotropic boundary phase is correspondingly shifts to rhombohedral phase. A uniform microstructure and excellent comprehensive properties were obtained at 1240 degrees C as the amount of Cr2O3 is 0.5 wt.%.
基金supported by the National Natural Science Foundation of China(No.52375580)the Guangdong Basic and Applied Basic Research Foundation(No.2024A1515011397)+2 种基金the Department of Education of Guangdong Province(No.2023ZDZX1036)the Guangzhou-HKUST(GZ)Joint Funding Program(No.2023A03J0688)the Guangzhou Basic and Applied Basic Research Scheme(No.2024A04J6466).
文摘Transient electronics,which can be controllably broken down with zero environmental impact,hold significant potential in implantable devices,hardware security,and disposable sensors.While miniaturization is essential for enhancing device performance,increasing integration density,and enabling new applications,degradable materials often face challenges with conventional microfabrication processes like lithography due to their sensitivity to heat and solvents.In this paper,we present a UV photodetector(PD)with micro-scale patterning,fabricated using a novel solvent-free material patterning method.The PD,consisting of molybdenum(Mo)as the electrode,zinc oxide(ZnO)as the photoactive material,and polyvinyl alcohol(PVA)as the substrate,can be dissolved in deionized(DI)water,leaving behind non-toxic byproducts.The device exhibits high responsivity over 50 A/W and an obvious response to varying sunlight intensities,demonstrating its potential for temporary,eco-friendly UV sensing applications.Additionally,we demonstrated that the photoresist used in the solvent-free material patterning method can be reused for subsequent fabrication while maintaining good registration,enhancing efficiency and reducing material waste.This approach provides a scalable and high-efficiency microfabrication strategy for integrating functional materials into unconventional platforms,offering broader applicability in next-generation transient,biodegradable,and flexible sensor technologies.
基金This work was supported by the Science and Technology Research and Developmental Program of Hebei, China （No.12273611） and the National Natural Science Foundation of China （Grant No. 51008005）.
文摘The N2O production in two nitrogen removal processes treating domestic wastewater was investigated in laboratory-scale aerobic-anoxic sequencing batch reactors （SBRs）. Results showed that N2O emission happened in the aerobic phase rather than in the anoxic phase. During the aerobic phase, the nitrogen conversion to N2O gas was 27.7% and 36.8% of NH＋-N loss for conventional biologic N-removal process and short-cut biologic N-removal process. The dissolved N2O was reduced to N2 in the anoxic denitrification phase. The N2O production rate increased with the increasing of nitrite concentration and ceased when NH＋-N oxidation was terminated. Higher nitrite accumulation resulted in higher NEO emission in the short-cut nitrogen removal process. Pulse-wise addition of 20 mg NO2 -N. L- 1 gave rise to 3-fold of N2O emission in the conventional N-removal process, while little change happened with 20 mg NOS-N L-1 was added to SBR1.
