We present a bidirectional reflection distribution function （BRDF） model for thermal coating surfaces based on a three-component reflection assumption, in which the specular reflection is given according to the micr...We present a bidirectional reflection distribution function （BRDF） model for thermal coating surfaces based on a three-component reflection assumption, in which the specular reflection is given according to the microfacet theory and Snell＇s law, the multiple reflection is considered Nth cosine distributed, and the volume scattering is uniformly distributed in reflection angles according to the experimental results. This model describes the reflection characteristics of thermal coating surfaces more completely and reasonably. Simulation and measurement results of two thermal coating samples SR107 and S781 are given to validate that this three-component model significantly improves the modeling accuracy for thermal coating surfaces compared with the existing BRDF models.展开更多
Silver coatings on the exterior surface of monolithic activated carbon（MAC） with different morphology were prepared by directly immersing MAC into [Ag（NH3）2]NO3 solution. Acid and base treatments were employed to ...Silver coatings on the exterior surface of monolithic activated carbon（MAC） with different morphology were prepared by directly immersing MAC into [Ag（NH3）2]NO3 solution. Acid and base treatments were employed to modify the surface oxygenic groups of MAC, respectively. The MACs＇ Brunauer-EmmettTeller（BET） surface area, surface groups, and silver coating morphology were characterized by N2 adsorption, elemental analysis（EA）, X-ray photoelectron spectroscopy（XPS）, and scanning electron microscopy（SEM）, respectively. The coating morphology was found to be closely related to the surface area and surface functional groups of MAC. For a raw MAC which contained a variety of oxygenic groups, HNO3 treatment enhanced the relative amount of highly oxidized groups such as carboxyl and carbonates, which disfavored the deposition of silver particles. By contrast, Na OH treatment significantly improved the amount of carbonyl groups, which in turn improved the deposition amount of silver. Importantly, lamella silver was produced on raw MAC while Na OH treatment resulted in granular particles because of the capping effect of carbonyl groups. At appropriate [Ag（NH3）2]NO3 concentrations, silver nanoparticles smaller than 100 nm were homogeneously dispersed on Na OH-treated MAC. The successful tuning of the size and morphology of silver coatings on MAC is promising for novel applications in air purification and for antibacterial or aesthetic purposes.展开更多
Functionalization of polymer foams by surface coating is of great interest for advanced flow-interactive materials working with well-controlled 3D open channels.However,realizing heavy functional coating via a fast an...Functionalization of polymer foams by surface coating is of great interest for advanced flow-interactive materials working with well-controlled 3D open channels.However,realizing heavy functional coating via a fast and recyclable way remains a big challenge.Here,inspired by the battery electrodes,we propose a scalable mechanic-assisted heavy coating strategy based on the design of sticky jammed fluid(SJF)to conquer the above challenge.Similar to the electrode slurry,the SJF is dominated by a high concentration of active material(≥20 wt%of active carbon,for instance)uniformly dispersed in a protein binder solution.Due to the sticky and solidrich nature of the SJF,one can realize a high coating efficiency of 60 wt%gain per coating.The critical factors controlling the coating processing and quality are further identified and discussed.Furthermore,the functionalized foam is demonstrated as a high-performance shape-customizable toxic gas remover,which can absorb formaldehyde very efficiently at different circumstances,including static adsorption,flow-based filtration,and source interception.Finally,the foam skeleton and the active materials are easily recycled by a facile solvent treatment.This study may inspire new scalable way for fast,heavy,and customizable functionalization of polymeric foams.展开更多
Two-dimensional（2 D） materials have attracted increasing attentions recently due to their unique physical and chemical properties. We herein report the synthesis of four chemically stable 2 D covalent organic nanosh...Two-dimensional（2 D） materials have attracted increasing attentions recently due to their unique physical and chemical properties. We herein report the synthesis of four chemically stable 2 D covalent organic nanosheets（CONs） with large lateral sizes（up to 200 mm） and high aspect ratios（〉20 000） at the air-water interface through the Langmuir-Blodgett method. These CONs exhibit good crystallinity proved by high resolution transmission electron microscopy（HRTEM） and selected area electron diffraction（SAED）. In addition, the hydrophobicity of these CONs can be systematically adjusted by the introduction of various functional groups, making them suitable as functional coating and membrane materials.展开更多
文摘We present a bidirectional reflection distribution function （BRDF） model for thermal coating surfaces based on a three-component reflection assumption, in which the specular reflection is given according to the microfacet theory and Snell＇s law, the multiple reflection is considered Nth cosine distributed, and the volume scattering is uniformly distributed in reflection angles according to the experimental results. This model describes the reflection characteristics of thermal coating surfaces more completely and reasonably. Simulation and measurement results of two thermal coating samples SR107 and S781 are given to validate that this three-component model significantly improves the modeling accuracy for thermal coating surfaces compared with the existing BRDF models.
基金Funded by the Interdisciplinary Program of Shanghai Jiao Tong University(YG2016MS24)
文摘Silver coatings on the exterior surface of monolithic activated carbon（MAC） with different morphology were prepared by directly immersing MAC into [Ag（NH3）2]NO3 solution. Acid and base treatments were employed to modify the surface oxygenic groups of MAC, respectively. The MACs＇ Brunauer-EmmettTeller（BET） surface area, surface groups, and silver coating morphology were characterized by N2 adsorption, elemental analysis（EA）, X-ray photoelectron spectroscopy（XPS）, and scanning electron microscopy（SEM）, respectively. The coating morphology was found to be closely related to the surface area and surface functional groups of MAC. For a raw MAC which contained a variety of oxygenic groups, HNO3 treatment enhanced the relative amount of highly oxidized groups such as carboxyl and carbonates, which disfavored the deposition of silver particles. By contrast, Na OH treatment significantly improved the amount of carbonyl groups, which in turn improved the deposition amount of silver. Importantly, lamella silver was produced on raw MAC while Na OH treatment resulted in granular particles because of the capping effect of carbonyl groups. At appropriate [Ag（NH3）2]NO3 concentrations, silver nanoparticles smaller than 100 nm were homogeneously dispersed on Na OH-treated MAC. The successful tuning of the size and morphology of silver coatings on MAC is promising for novel applications in air purification and for antibacterial or aesthetic purposes.
基金sponsored by the Double First-Class Construction Funds of Sichuan University and National Natural Science Foundation of China(NNSFC)financial support from the National Natural Science Foundation of China(NNSFC grants 51873126,51422305,and 51721091).
文摘Functionalization of polymer foams by surface coating is of great interest for advanced flow-interactive materials working with well-controlled 3D open channels.However,realizing heavy functional coating via a fast and recyclable way remains a big challenge.Here,inspired by the battery electrodes,we propose a scalable mechanic-assisted heavy coating strategy based on the design of sticky jammed fluid(SJF)to conquer the above challenge.Similar to the electrode slurry,the SJF is dominated by a high concentration of active material(≥20 wt%of active carbon,for instance)uniformly dispersed in a protein binder solution.Due to the sticky and solidrich nature of the SJF,one can realize a high coating efficiency of 60 wt%gain per coating.The critical factors controlling the coating processing and quality are further identified and discussed.Furthermore,the functionalized foam is demonstrated as a high-performance shape-customizable toxic gas remover,which can absorb formaldehyde very efficiently at different circumstances,including static adsorption,flow-based filtration,and source interception.Finally,the foam skeleton and the active materials are easily recycled by a facile solvent treatment.This study may inspire new scalable way for fast,heavy,and customizable functionalization of polymeric foams.
基金supported by National University of Singapore No. CENGas R-261-508-001-646)Ministry of Education – Singapore ( 13No. MOE Ac RF Tier 1 R-279-000-472-112)
文摘Two-dimensional（2 D） materials have attracted increasing attentions recently due to their unique physical and chemical properties. We herein report the synthesis of four chemically stable 2 D covalent organic nanosheets（CONs） with large lateral sizes（up to 200 mm） and high aspect ratios（〉20 000） at the air-water interface through the Langmuir-Blodgett method. These CONs exhibit good crystallinity proved by high resolution transmission electron microscopy（HRTEM） and selected area electron diffraction（SAED）. In addition, the hydrophobicity of these CONs can be systematically adjusted by the introduction of various functional groups, making them suitable as functional coating and membrane materials.
