Well aligned nanotubes with diameter of 30—50 nm have been synthesized on a porous alumina template by microwave plasma enhanced chemical vapor deposition (MW PECVD). By this means, the control over either diameter o...Well aligned nanotubes with diameter of 30—50 nm have been synthesized on a porous alumina template by microwave plasma enhanced chemical vapor deposition (MW PECVD). By this means, the control over either diameter or length of the nanotubes could be realized. The hollow structure and vertically aligned features have been verified by scanning electron and transmission electron microscopic images. In comparison with the reported fabrication methods, lower synthesis temperature (below 520 ℃) and simpler process (no negative dc bias applied) have been achieved, which could be of great importance for both theoretical research and pratical applications.展开更多
Spherical or dendritic silver nanoparticles have been synthesized by an electrochemical technique in an aqueous solution containing L cysteine or citric acid. The silver nanoparticles are characterized by powder X ray...Spherical or dendritic silver nanoparticles have been synthesized by an electrochemical technique in an aqueous solution containing L cysteine or citric acid. The silver nanoparticles are characterized by powder X ray diffraction(XRD), transmission electron microscope(TEM) and UV Vis absorption spectrum. A typical XRD pattern of the as prepared silver nanoparticles shows the presence of the diffraction peaks corresponding to the (111), (200), (220), (311) planes. All the peaks in the XRD pattern can be indexed as a fcc structure(JCPDS, No.4 0783). The TEM image in the presence of L cysteine shows spherical nanoparticles. But the TEM image in the presence of citric acid shows dendritic nanoparticles. [WT5HZ]展开更多
The chemiluminescence (CL) generated from the hydrogen peroxide oxided by periodate could be enhanced differently by polyhydrophenols, such as pyrogallol, phloroglucinol, pyrocatechol, resorcinol and parodioxybenzene....The chemiluminescence (CL) generated from the hydrogen peroxide oxided by periodate could be enhanced differently by polyhydrophenols, such as pyrogallol, phloroglucinol, pyrocatechol, resorcinol and parodioxybenzene. Furthermore, the CL could be improved in the presence of the trace non-polar organic solvent, the possible mechanism was proposed. Based on which a sensitive CL method for polyhydrophenols has been built. The linear ranges of determination for pyrogallol, phloroglucinol, pyrocatechol, resorcinol and parodioxybenzene were 1×10-5～2×10-7 mol/L, 1×10-3～1×10-5 mol/L, 1×10-4～6×10-6 mol/L, 1×10-3～2×10-5 mol/L and 1×10-3～6×10-5 mol/L, respectively, and their detection limits were 7.2×10-8 mol/L, 6.8×10-6 mol/L, 2.1×10-6 mol/L , 7.1×10-6 mol/L and 2.2×10-5 mol/L respectively.展开更多
文摘Well aligned nanotubes with diameter of 30—50 nm have been synthesized on a porous alumina template by microwave plasma enhanced chemical vapor deposition (MW PECVD). By this means, the control over either diameter or length of the nanotubes could be realized. The hollow structure and vertically aligned features have been verified by scanning electron and transmission electron microscopic images. In comparison with the reported fabrication methods, lower synthesis temperature (below 520 ℃) and simpler process (no negative dc bias applied) have been achieved, which could be of great importance for both theoretical research and pratical applications.
文摘Spherical or dendritic silver nanoparticles have been synthesized by an electrochemical technique in an aqueous solution containing L cysteine or citric acid. The silver nanoparticles are characterized by powder X ray diffraction(XRD), transmission electron microscope(TEM) and UV Vis absorption spectrum. A typical XRD pattern of the as prepared silver nanoparticles shows the presence of the diffraction peaks corresponding to the (111), (200), (220), (311) planes. All the peaks in the XRD pattern can be indexed as a fcc structure(JCPDS, No.4 0783). The TEM image in the presence of L cysteine shows spherical nanoparticles. But the TEM image in the presence of citric acid shows dendritic nanoparticles. [WT5HZ]
文摘The chemiluminescence (CL) generated from the hydrogen peroxide oxided by periodate could be enhanced differently by polyhydrophenols, such as pyrogallol, phloroglucinol, pyrocatechol, resorcinol and parodioxybenzene. Furthermore, the CL could be improved in the presence of the trace non-polar organic solvent, the possible mechanism was proposed. Based on which a sensitive CL method for polyhydrophenols has been built. The linear ranges of determination for pyrogallol, phloroglucinol, pyrocatechol, resorcinol and parodioxybenzene were 1×10-5～2×10-7 mol/L, 1×10-3～1×10-5 mol/L, 1×10-4～6×10-6 mol/L, 1×10-3～2×10-5 mol/L and 1×10-3～6×10-5 mol/L, respectively, and their detection limits were 7.2×10-8 mol/L, 6.8×10-6 mol/L, 2.1×10-6 mol/L , 7.1×10-6 mol/L and 2.2×10-5 mol/L respectively.
