Cellulose is the most abundant organic macromolecule in nature and is renewable,degradable,and biocompatible.The structure of native cellulose has not yet been completely elucidated.Part of cellulose is tightly combin...Cellulose is the most abundant organic macromolecule in nature and is renewable,degradable,and biocompatible.The structure of native cellulose has not yet been completely elucidated.Part of cellulose is tightly combined with lignin macromolecules through chemical bonds to form cellulose-lignin complexes(CLC).The existence of the CLC structure inhibits the complete separation of cellulose from lignocellulosic material,which not only increases the consumption of chemicals in the cooking process and causes environmental pollution,but also makes the cellulose subject to certain degradation during the deep delignification process.Therefore,elucidation of the relationship between the cellulose-lignin connection structure and performance is of great significance for efficient separation of cellulose.This article reviews the current research status of CLC and discusses the research progress regarding its biodegradation characteristics.展开更多
Near-infrared (NIR) transparent optical filters show great promise in night vision and receiving windows. However, NIR optical filters are generally prepared by laborious, environmentally unfriendly processes that inv...Near-infrared (NIR) transparent optical filters show great promise in night vision and receiving windows. However, NIR optical filters are generally prepared by laborious, environmentally unfriendly processes that involve metal oxides or petroleum-based polymers. We propose a lignin capturing–fusing approach to manufacturing optical biofilters based on molecular collaboration between lignin and cellulose from waste agricultural biomass. In this process, lignin is captured via self-assembly in a cellulose network;then, the lignin is fused to fill gaps and hold the cellulose fibers tightly. The resulting optical biofilter featured a dense structure and smooth surface with NIR transmittance of ~90%, ultralow haze of close to 0%, strong ultraviolet-visible light blocking (~100% at 400 nm and 57.58% to 98.59% at 550 nm). Further, the optical biofilter has comprehensive stability, including water stability, solvent stability, thermal stability, and environmental stability. Because of its unique properties, the optical biofilter demonstrates potential applications in the NIR region, such as an NIR-transmitting window, NIR night vision, and privacy protection. These applications represent a promising route to produce NIR transparent optical filters starting from lignocellulose biomass waste.展开更多
With the ability to generate forms with high efficiency and elegant geometry,topology optimization has been increasingly used in architectural and structural designs.However,the conventional topology optimization tech...With the ability to generate forms with high efficiency and elegant geometry,topology optimization has been increasingly used in architectural and structural designs.However,the conventional topology optimization techniques aim at achieving the structurally most efficient solution without any potential for architects or designers to control the design details.This paper introduces three strategies based on Bi-directional Evolutionary Structural Optimization(BESO)method to artificially pre-design the topological optimized structures.These strategies have been successfully applied in the computational morphogenesis of various structures for solving practical design problems.The results demonstrate that the developed methodology can provide the designer with structurally efficient and topologically different solutions according to their proposed designs with multi-filter radii,multi-volume fractions,and multi-weighting coefficients.This work establishes a general approach to integrating objective topology optimization methods with subjective human design preferences,which has great potential for practical applications in architecture and engineering industry.展开更多
Coal moisture control (CMC) in coking process, which reduces coal moisture before loading the coal into the coke oven, allows substantial reduction in coking energy consumption and increase in coke productivity. The...Coal moisture control (CMC) in coking process, which reduces coal moisture before loading the coal into the coke oven, allows substantial reduction in coking energy consumption and increase in coke productivity. The technology is seeking to integrate the coal classification, thus calling it the coal classifying moisture control (CCMC), to separate the fine and coarse coal fractions in the CMC process so that the downstream coal crushing can only treat the coarse fraction. CCMC adopts a reactor that integrates a fluidized bottom section and a pneumatic conveying top section. The present work investigates the pneumatic classification behavior in a laboratory CCMC reactor with such a configuration by removing the coal fraction below a given size (e.g., 3.0 mm) from a 0 to 20.0 mm coal feed. The results show that the coal classification were dominated by the gas velocity in the top conveying section, and the required gas velocity for ensuring the maximal degree of removing a fine coal fraction could be roughly predicted by the Richardson and Zaki equation. The effect of bottom fluidization on the performance of CCMC is also examined.展开更多
基金The authors are grateful for the support of the National Natural Science Foundation of China(No.21878070)Hubei Provincial Universities Outstanding Young and Middle-aged Technological Innovation Team Project(No.T201205).
文摘Cellulose is the most abundant organic macromolecule in nature and is renewable,degradable,and biocompatible.The structure of native cellulose has not yet been completely elucidated.Part of cellulose is tightly combined with lignin macromolecules through chemical bonds to form cellulose-lignin complexes(CLC).The existence of the CLC structure inhibits the complete separation of cellulose from lignocellulosic material,which not only increases the consumption of chemicals in the cooking process and causes environmental pollution,but also makes the cellulose subject to certain degradation during the deep delignification process.Therefore,elucidation of the relationship between the cellulose-lignin connection structure and performance is of great significance for efficient separation of cellulose.This article reviews the current research status of CLC and discusses the research progress regarding its biodegradation characteristics.
基金This research was undertaken with funding from Hubei Provincial Universities Outstanding Young and Middle-aged Technological Innovation Team Project (grant no. T201205)the Foundation of Key Laboratory of Pulp and Paper Science and Technology of Ministry of Education, Qilu University of Technology (grant no. KF201623)+1 种基金C.C. acknowledges the National Natural Science Foundation of China (grant no. 52273091)the Fundamental Research Funds for the Central Universities (grant no. 2042022kf1177)' the start-up fund from Wuhan University (grant no. 691000003).
文摘Near-infrared (NIR) transparent optical filters show great promise in night vision and receiving windows. However, NIR optical filters are generally prepared by laborious, environmentally unfriendly processes that involve metal oxides or petroleum-based polymers. We propose a lignin capturing–fusing approach to manufacturing optical biofilters based on molecular collaboration between lignin and cellulose from waste agricultural biomass. In this process, lignin is captured via self-assembly in a cellulose network;then, the lignin is fused to fill gaps and hold the cellulose fibers tightly. The resulting optical biofilter featured a dense structure and smooth surface with NIR transmittance of ~90%, ultralow haze of close to 0%, strong ultraviolet-visible light blocking (~100% at 400 nm and 57.58% to 98.59% at 550 nm). Further, the optical biofilter has comprehensive stability, including water stability, solvent stability, thermal stability, and environmental stability. Because of its unique properties, the optical biofilter demonstrates potential applications in the NIR region, such as an NIR-transmitting window, NIR night vision, and privacy protection. These applications represent a promising route to produce NIR transparent optical filters starting from lignocellulose biomass waste.
文摘With the ability to generate forms with high efficiency and elegant geometry,topology optimization has been increasingly used in architectural and structural designs.However,the conventional topology optimization techniques aim at achieving the structurally most efficient solution without any potential for architects or designers to control the design details.This paper introduces three strategies based on Bi-directional Evolutionary Structural Optimization(BESO)method to artificially pre-design the topological optimized structures.These strategies have been successfully applied in the computational morphogenesis of various structures for solving practical design problems.The results demonstrate that the developed methodology can provide the designer with structurally efficient and topologically different solutions according to their proposed designs with multi-filter radii,multi-volume fractions,and multi-weighting coefficients.This work establishes a general approach to integrating objective topology optimization methods with subjective human design preferences,which has great potential for practical applications in architecture and engineering industry.
基金support of the National Natural Science Foundation of China (21076217)the National Basic Research Program of China(2011CB201304)+2 种基金the National Key Technology Development Programs(2009BAC64B05 and 2010BAC66B01)the National High-Tech R&D Program of China(2009AA02Z209)the cooperation of Henan Shuncheng Coal Chemical Group Company
文摘Coal moisture control (CMC) in coking process, which reduces coal moisture before loading the coal into the coke oven, allows substantial reduction in coking energy consumption and increase in coke productivity. The technology is seeking to integrate the coal classification, thus calling it the coal classifying moisture control (CCMC), to separate the fine and coarse coal fractions in the CMC process so that the downstream coal crushing can only treat the coarse fraction. CCMC adopts a reactor that integrates a fluidized bottom section and a pneumatic conveying top section. The present work investigates the pneumatic classification behavior in a laboratory CCMC reactor with such a configuration by removing the coal fraction below a given size (e.g., 3.0 mm) from a 0 to 20.0 mm coal feed. The results show that the coal classification were dominated by the gas velocity in the top conveying section, and the required gas velocity for ensuring the maximal degree of removing a fine coal fraction could be roughly predicted by the Richardson and Zaki equation. The effect of bottom fluidization on the performance of CCMC is also examined.