Microwave(MW)assisted catalyst-free hydrolysis of fibrous cellulose(FC,cellulolysis)at 200℃promoted a cellulose conversion o f ca.37.2%and quantitative production o f valuable C5/C6 sugars(e.g.,glucose)and the accord...Microwave(MW)assisted catalyst-free hydrolysis of fibrous cellulose(FC,cellulolysis)at 200℃promoted a cellulose conversion o f ca.37.2%and quantitative production o f valuable C5/C6 sugars(e.g.,glucose)and the according platform biochemicals(e.g.,5-hydroxymethylfurfliral),corresponding to an overall selectivity o f 96.5%.Conversely,conventional hydrothermal cellulolysis under similar conditions was not effective,even after 24 h,carbonising the FC.Based on the systematic study of MW-assisted cellulolysis,the specific interaction between water molecules and macroscopic FC under the MW irradiation was proposed,accounting for the interpretation o f the experimental observation.The kinetic energy o f water molecules under the MW irradiation facilitated the C-C(in the non-hindered surface-CH2OH groups)and C-O-C bond breaking(inside the cellulose cavities)in FC,producing primary cellulolysis products of xylose,glucose and cellobiose.展开更多
N^+ ion irradiation is utilized to tune the structure and mechanical properties of a Cu48Zr47.2Al4Nb0.8 bulk metallic glass composite(BMGC). Ion irradiation increases the disorder near the surface, as probed by neutro...N^+ ion irradiation is utilized to tune the structure and mechanical properties of a Cu48Zr47.2Al4Nb0.8 bulk metallic glass composite(BMGC). Ion irradiation increases the disorder near the surface, as probed by neutron diffraction, and, moreover, causes the phase transformation from B2Cu Zr to B19’ CuZr martensitic phase in the studied BMGC. The tensile plasticity of the BMGC is dramatically improved after ion irradiation, which results from multiple shear banding on the surface and the martensitic transformation of the B2 to B19’ Cu Zr martensitic phase. The experimental results are strongly corroborated by complementary molecular dynamic simulations.展开更多
文摘Microwave(MW)assisted catalyst-free hydrolysis of fibrous cellulose(FC,cellulolysis)at 200℃promoted a cellulose conversion o f ca.37.2%and quantitative production o f valuable C5/C6 sugars(e.g.,glucose)and the according platform biochemicals(e.g.,5-hydroxymethylfurfliral),corresponding to an overall selectivity o f 96.5%.Conversely,conventional hydrothermal cellulolysis under similar conditions was not effective,even after 24 h,carbonising the FC.Based on the systematic study of MW-assisted cellulolysis,the specific interaction between water molecules and macroscopic FC under the MW irradiation was proposed,accounting for the interpretation o f the experimental observation.The kinetic energy o f water molecules under the MW irradiation facilitated the C-C(in the non-hindered surface-CH2OH groups)and C-O-C bond breaking(inside the cellulose cavities)in FC,producing primary cellulolysis products of xylose,glucose and cellobiose.
基金financially supported by the National Natural Science Foundation of China (Nos. 51871076, 51671070, 51827801, 51671067, and 51671071)the Opening Funding of the State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology, China (No. AWJ-Z16-02)the Chinese Scholarship Council (CSC) and the German Science Foundation (DFG) (Nos. PA 2275/2-1, PA 2275/4-1, and PA 2275/6-1)
文摘N^+ ion irradiation is utilized to tune the structure and mechanical properties of a Cu48Zr47.2Al4Nb0.8 bulk metallic glass composite(BMGC). Ion irradiation increases the disorder near the surface, as probed by neutron diffraction, and, moreover, causes the phase transformation from B2Cu Zr to B19’ CuZr martensitic phase in the studied BMGC. The tensile plasticity of the BMGC is dramatically improved after ion irradiation, which results from multiple shear banding on the surface and the martensitic transformation of the B2 to B19’ Cu Zr martensitic phase. The experimental results are strongly corroborated by complementary molecular dynamic simulations.