： The four heteropoly isomers K3H2[α-,β i-SiW11Fe(H2O)O39]· xH2O(β i=β 1,β 2,β 3)were prepared and Characterized by elementary analysis, IR and UV Spectroscopy. Its electrochemical behavior in aqueous solu...： The four heteropoly isomers K3H2[α-,β i-SiW11Fe(H2O)O39]· xH2O(β i=β 1,β 2,β 3)were prepared and Characterized by elementary analysis, IR and UV Spectroscopy. Its electrochemical behavior in aqueous solution has been discussed. The order of Polarographic half-wave potential E1/2 of heteropoly anions is as follows:β 2 >β 1 >β 3 >α . Its reduction process involves an one-electron reduction of Fe? and a pair of two-electron reduction of W? . Epolidation of maleic acid with H2O2 Catalyzed by heteropoly positional isomers was studied.β 3 isomers are the most active.展开更多
The four heteropoly isomers K3H3[α ,β i SiW11Zn(H2O)O39]· XH2O(β i=β 1,β 2,β 3) were prepared and characterized by elementary analysis, IR and UV spectroscopy, polargraphy and cyclic voitammetry, 183W NMR a...The four heteropoly isomers K3H3[α ,β i SiW11Zn(H2O)O39]· XH2O(β i=β 1,β 2,β 3) were prepared and characterized by elementary analysis, IR and UV spectroscopy, polargraphy and cyclic voitammetry, 183W NMR and XPS experiments. And these compounds can catalyze epoxidation reaction of olefine.展开更多
A new precusor of activated carbon material--sugar was pyrolyzed under many different conditions. Experiments were carried out to search for optimal pyrolyzing conditions. It was found that sugar should be carbonized ...A new precusor of activated carbon material--sugar was pyrolyzed under many different conditions. Experiments were carried out to search for optimal pyrolyzing conditions. It was found that sugar should be carbonized at 700 ℃ and activated with potassium hydroxide at 800 ℃. The activated carbon prepared from pyrolytic treatment of sugar is therefore potential candidates as electrode material of electric double layer capacitor.展开更多
Carhons were prepared at different temperatures by pyrolytic treatment of phenolformaldehyde resin molded with ZnCl2 in advance. X-ray structure analyses have shown that these carbon are essentially amorphous with rat...Carhons were prepared at different temperatures by pyrolytic treatment of phenolformaldehyde resin molded with ZnCl2 in advance. X-ray structure analyses have shown that these carbon are essentially amorphous with rather loose structure of molecular size order with an interlayer distance of 0.36—0.37 nm. Using electrochemical methods, we have studied the insertion of lithium within these materials. Resole resins, heated to 580 ℃, have a reversible capacity of about 400 mA·h/g, which is beyond the theoretical capacity of graphite（372 mA·h/g） and discover that carbons with a smaller crystallite size and large interlayer distance have the larger discharge capacity.展开更多
文摘： The four heteropoly isomers K3H2[α-,β i-SiW11Fe(H2O)O39]· xH2O(β i=β 1,β 2,β 3)were prepared and Characterized by elementary analysis, IR and UV Spectroscopy. Its electrochemical behavior in aqueous solution has been discussed. The order of Polarographic half-wave potential E1/2 of heteropoly anions is as follows:β 2 >β 1 >β 3 >α . Its reduction process involves an one-electron reduction of Fe? and a pair of two-electron reduction of W? . Epolidation of maleic acid with H2O2 Catalyzed by heteropoly positional isomers was studied.β 3 isomers are the most active.
文摘The four heteropoly isomers K3H3[α ,β i SiW11Zn(H2O)O39]· XH2O(β i=β 1,β 2,β 3) were prepared and characterized by elementary analysis, IR and UV spectroscopy, polargraphy and cyclic voitammetry, 183W NMR and XPS experiments. And these compounds can catalyze epoxidation reaction of olefine.
文摘A new precusor of activated carbon material--sugar was pyrolyzed under many different conditions. Experiments were carried out to search for optimal pyrolyzing conditions. It was found that sugar should be carbonized at 700 ℃ and activated with potassium hydroxide at 800 ℃. The activated carbon prepared from pyrolytic treatment of sugar is therefore potential candidates as electrode material of electric double layer capacitor.
文摘Carhons were prepared at different temperatures by pyrolytic treatment of phenolformaldehyde resin molded with ZnCl2 in advance. X-ray structure analyses have shown that these carbon are essentially amorphous with rather loose structure of molecular size order with an interlayer distance of 0.36—0.37 nm. Using electrochemical methods, we have studied the insertion of lithium within these materials. Resole resins, heated to 580 ℃, have a reversible capacity of about 400 mA·h/g, which is beyond the theoretical capacity of graphite（372 mA·h/g） and discover that carbons with a smaller crystallite size and large interlayer distance have the larger discharge capacity.
