Meihua brand supermolecute polyethylene, a product of the Beijing No.2 Assistant Factory, is a chemically resistant thermoplastic for industrial use, grinding, and punching. With a low friction coefficient, it is good...Meihua brand supermolecute polyethylene, a product of the Beijing No.2 Assistant Factory, is a chemically resistant thermoplastic for industrial use, grinding, and punching. With a low friction coefficient, it is good in lubrication and insulauon situations and can be used at under -269 C in liquid展开更多
Supermolecular compounds of glycine monosubstituted heteropolytungstates isomer with Keggin structure βi-K6-n(HGly)n SiW11M(H2O)O39 ·xH2O (M=Co2+, Ni2+; βi=β2, β3) were synthesized and characterized by means ...Supermolecular compounds of glycine monosubstituted heteropolytungstates isomer with Keggin structure βi-K6-n(HGly)n SiW11M(H2O)O39 ·xH2O (M=Co2+, Ni2+; βi=β2, β3) were synthesized and characterized by means of elementary analysis, IR, UV, TG-DTA, X-ray diffraction, polarography and CV. The results indicate that glycin combines the electrostatic effect with heteropolytungstates isomer. The heteropoly anion still remains its Keggin structure in supermolecular compounds. The electrochemical behavior of the compound in 1 mol·L-1 HAc-NaAc shows that two redox waves correspond to two two-electron processes attributing to the reduction of SiW11Co(H2O)O39 6-. Steady-state fluorescence spectrum shows two intenser fluorescence emission peaks in 447 nm and 486 nm appeared after the supermolecular compound being excited by the excitation wavelength in 274 nm.展开更多
文摘Meihua brand supermolecute polyethylene, a product of the Beijing No.2 Assistant Factory, is a chemically resistant thermoplastic for industrial use, grinding, and punching. With a low friction coefficient, it is good in lubrication and insulauon situations and can be used at under -269 C in liquid
文摘Supermolecular compounds of glycine monosubstituted heteropolytungstates isomer with Keggin structure βi-K6-n(HGly)n SiW11M(H2O)O39 ·xH2O (M=Co2+, Ni2+; βi=β2, β3) were synthesized and characterized by means of elementary analysis, IR, UV, TG-DTA, X-ray diffraction, polarography and CV. The results indicate that glycin combines the electrostatic effect with heteropolytungstates isomer. The heteropoly anion still remains its Keggin structure in supermolecular compounds. The electrochemical behavior of the compound in 1 mol·L-1 HAc-NaAc shows that two redox waves correspond to two two-electron processes attributing to the reduction of SiW11Co(H2O)O39 6-. Steady-state fluorescence spectrum shows two intenser fluorescence emission peaks in 447 nm and 486 nm appeared after the supermolecular compound being excited by the excitation wavelength in 274 nm.
