A silylated melamine sponge(SMS)was prepared by two simple steps,namely,immersion and dehydration of a melamine sponge coated with methyltrichlorosilane.The silylated structure of SMS was characterized by FT-IR(Fourie...A silylated melamine sponge(SMS)was prepared by two simple steps,namely,immersion and dehydration of a melamine sponge coated with methyltrichlorosilane.The silylated structure of SMS was characterized by FT-IR(Fourier-transform infrared)spectroscopy,SEM(Scanning electron microscopy)and in terms of water contact angles.Its oil-water absorption and separation capacities were measured by FT-IR and UV-visible spectrophoto-metry.The experimental results have shown that oligomeric silanol covalently bonds by Si-N onto the surface of melamine sponge skeletons.SMS has shown superhydrophobicity with a water contact angle exceeding 150°±1°,a better separation efficiency with regard to diesel oil(by 99.31%(wt/wt%)in oil-water mixture and even up to 99.99%(wt/wt%)for diesel oil in its saturated aqueous solution.Moreover,SMS inherited the intrinsicflame retardancy of the melamine sponge.In general,SMS has shown superhydrophobicity,high porosity,excellent selectivity,remarkable recyclability,and better absorption capacity for various oils and organic solvents,and a high separation efficiency for oil in saturated aqueous solutions.展开更多
It is a new attempt to extend the differential quadrature method(DQM)to stability analysis ofthe straight and curved centerline pipes conveying fluid.Emphasis is placed on the study of the influences ofseveral paramet...It is a new attempt to extend the differential quadrature method(DQM)to stability analysis ofthe straight and curved centerline pipes conveying fluid.Emphasis is placed on the study of the influences ofseveral parameters on the critical flow velocity’.Compared to other methods,this method can more easily dealwith the pipe with spring support at its boundaries and asks for much less computing effort while giving ac-ceptable precision in the numerical results.展开更多
基金funded by Qingyang Science and Technology Support Project(KT2019-03)。
文摘A silylated melamine sponge(SMS)was prepared by two simple steps,namely,immersion and dehydration of a melamine sponge coated with methyltrichlorosilane.The silylated structure of SMS was characterized by FT-IR(Fourier-transform infrared)spectroscopy,SEM(Scanning electron microscopy)and in terms of water contact angles.Its oil-water absorption and separation capacities were measured by FT-IR and UV-visible spectrophoto-metry.The experimental results have shown that oligomeric silanol covalently bonds by Si-N onto the surface of melamine sponge skeletons.SMS has shown superhydrophobicity with a water contact angle exceeding 150°±1°,a better separation efficiency with regard to diesel oil(by 99.31%(wt/wt%)in oil-water mixture and even up to 99.99%(wt/wt%)for diesel oil in its saturated aqueous solution.Moreover,SMS inherited the intrinsicflame retardancy of the melamine sponge.In general,SMS has shown superhydrophobicity,high porosity,excellent selectivity,remarkable recyclability,and better absorption capacity for various oils and organic solvents,and a high separation efficiency for oil in saturated aqueous solutions.
基金National Key Project of China (No.PD9521907)the National Science Foundation of China (No.19872025).
文摘It is a new attempt to extend the differential quadrature method(DQM)to stability analysis ofthe straight and curved centerline pipes conveying fluid.Emphasis is placed on the study of the influences ofseveral parameters on the critical flow velocity’.Compared to other methods,this method can more easily dealwith the pipe with spring support at its boundaries and asks for much less computing effort while giving ac-ceptable precision in the numerical results.
