Microwave(MW)drying method was adopted to enhance the liquid permeability of Scots pine lumber.Structure changes were characterized by stereoscope microscope,scanned electron microscope(SEM)and transmission electron m...Microwave(MW)drying method was adopted to enhance the liquid permeability of Scots pine lumber.Structure changes were characterized by stereoscope microscope,scanned electron microscope(SEM)and transmission electron microscope(TEM)examination.Pore parameters before and after MW treatment were detected by mercury intrusion porosimetry(MIP)method,and the effect of structure changes on liquid permeability were analyzed.As stereoscope microscope,SEM and TEM examination results showed,macro and micro checks mainly developed at intercellcular of tracheids,intercellular of ray parenchyma and tracheid,while these checks extend main along the radial-longitudinal plane.Pit border destruction,aspirated pits’orus translocation and micro-checks in tracheid cell wall were also observed.MIP test shown that pore volume and pore area increased as macro and micro checks generated to form new cavities.Microstructure changes would increase the quantity of pores or enlarge the pore diameter.Liquid flow pathways increased as macro and micro checks generated,aspirated pits reopened to form new pathways;liquid flow efficiency improved as porosity,pore volume and pore diameter increased which facilitated the liquid flow.展开更多
Recent studies have suggested that rare earth(RE)elements in catalysts significantly influence the performance of the ammonia synthesis.The REs appear in various forms in the ammonia synthesis catalysts including supp...Recent studies have suggested that rare earth(RE)elements in catalysts significantly influence the performance of the ammonia synthesis.The REs appear in various forms in the ammonia synthesis catalysts including supports(oxides,hydrides,and nitrides),promotors,and intermetallic.Besides the conventional RE oxide-supporting catalysts(mainly Ru/REO),some new RE-containing catalyst systems,such as electrode and nitride systems,could drive the ammonia synthesis via a benign Mars-van Krevelen mechanism or multi-active-site mode,affording high ammonia synthesis performance under mild conditions.These works demonstrate the great potential of RE-containing catalysts for more efficient ammonia synthesis.This review summarizes the contributions of different kinds of RE-based catalysts and highlights the function mechanism of incorporated REs.Finally,an overview of this area and the challenges for further investigation are provided.展开更多
基金supported by Key Research&Development Program of Zhejiang Province(2021C02012)Chinese National Natural Science Foundation,Study on Pore Structure and Liquid Permeate Mechanism of Moso Bamboo(31700489).
文摘Microwave(MW)drying method was adopted to enhance the liquid permeability of Scots pine lumber.Structure changes were characterized by stereoscope microscope,scanned electron microscope(SEM)and transmission electron microscope(TEM)examination.Pore parameters before and after MW treatment were detected by mercury intrusion porosimetry(MIP)method,and the effect of structure changes on liquid permeability were analyzed.As stereoscope microscope,SEM and TEM examination results showed,macro and micro checks mainly developed at intercellcular of tracheids,intercellular of ray parenchyma and tracheid,while these checks extend main along the radial-longitudinal plane.Pit border destruction,aspirated pits’orus translocation and micro-checks in tracheid cell wall were also observed.MIP test shown that pore volume and pore area increased as macro and micro checks generated to form new cavities.Microstructure changes would increase the quantity of pores or enlarge the pore diameter.Liquid flow pathways increased as macro and micro checks generated,aspirated pits reopened to form new pathways;liquid flow efficiency improved as porosity,pore volume and pore diameter increased which facilitated the liquid flow.
基金the National Natural Science Foundation of China(Nos.51872242 and 21802120)the Fundamental Research Funds for the Central Universities(No.D5000220172)+1 种基金the Postdoctoral Research Foundation of China(No.2021M692634)are greatly appreciatedsupported by the JSPS Kahenhi Grant-in-Aid(No.17H06153).
文摘Recent studies have suggested that rare earth(RE)elements in catalysts significantly influence the performance of the ammonia synthesis.The REs appear in various forms in the ammonia synthesis catalysts including supports(oxides,hydrides,and nitrides),promotors,and intermetallic.Besides the conventional RE oxide-supporting catalysts(mainly Ru/REO),some new RE-containing catalyst systems,such as electrode and nitride systems,could drive the ammonia synthesis via a benign Mars-van Krevelen mechanism or multi-active-site mode,affording high ammonia synthesis performance under mild conditions.These works demonstrate the great potential of RE-containing catalysts for more efficient ammonia synthesis.This review summarizes the contributions of different kinds of RE-based catalysts and highlights the function mechanism of incorporated REs.Finally,an overview of this area and the challenges for further investigation are provided.
