Ab initio and density functional theory calculations have been carried out to investigate the reaction of hydroxyl radical （OH） and 1,1,1-trichloroethane （CH3CCl3）. The potential energy surface has been given acco...Ab initio and density functional theory calculations have been carried out to investigate the reaction of hydroxyl radical （OH） and 1,1,1-trichloroethane （CH3CCl3）. The potential energy surface has been given according to the relative energies calculated at the MP2/cc-pVTZ level after the spin projection （PMP2）. Five reaction channels were identified and the intramolecular hydrogen bonding was observed in some transition state structures. The barrier heights and reaction enthalpies calculated for all possible channels show that the hydrogen abstraction channel is predominant kinetically and thermodynamically. The contribution from other channels was predicted to be minor.展开更多
Reduction of a series of N,N＇-diaryl adipyl bis-azo compounds using hydrazine hydrate as reductant was investigated. The products were characterized by elemental analysis, IR and 1H NMR methods and confirmed to be N,...Reduction of a series of N,N＇-diaryl adipyl bis-azo compounds using hydrazine hydrate as reductant was investigated. The products were characterized by elemental analysis, IR and 1H NMR methods and confirmed to be N,N＇-diaryl adipyl dihydrazine. The results show that hydrazine hydrate can selectively reduce azo bonds with other potential reducible bonds intact in the N,N＇-diaryl adipyl bis-azo compounds. The yields are high up to 92% under mild reaction conditions. According to the previous reports, this reduction process was attributed to an indirect reduction mechanism through an intermediate diimide.展开更多
The reaction mechanism of 1-chloroethane with hydroxyl radical has been investigated by using density functional theory （DFT） B3LYP/6-31G （d, p） method. All bond dissociation enthalpies were computed at the same t...The reaction mechanism of 1-chloroethane with hydroxyl radical has been investigated by using density functional theory （DFT） B3LYP/6-31G （d, p） method. All bond dissociation enthalpies were computed at the same theoretical level. It was found that hydrogen abstraction pathway is the most favorable. There are two hydrogen abstraction pathways with activation barriers of 0.630 and 4.988 kJ/mol, respectively, while chlorine abstraction pathway was not found. It was observed that activation energies have a more reasonable correlation with the reaction enthalpy changes （ΔHr） than with bond dissociation enthalpies （BDE）.展开更多
Based on the Onion-Peeling algorithm （OPA） principle, we present a simplified model for analysing photoion and photoelectron images, which allows the analysis of experimental raw images. A three-dimensional distribu...Based on the Onion-Peeling algorithm （OPA） principle, we present a simplified model for analysing photoion and photoelectron images, which allows the analysis of experimental raw images. A three-dimensional distribution of the nascent charged particles, from which the radial and angular distributions are deduced, can be obtained more easily by this model than by the commonly used procedures. The analysis results of Xe photoelectron images by this model are compared with those from the standard Hankel-Abel inversion. The results imply that this model can be used for complicated （many peaks） and ＇ditffcult＇ （low signal-to-noise） images with cylindrical symmetries, and can provide a reliable reconstruction in some cases when the commonly used Haukel Abel transform method fails.展开更多
Fragmentation of CO in a linearly polarized femtosecond laser field within the intensity order of 10^14 W.cm^-2 at 820nm is investigated experimentally by using velocity mapping technique. According to the observed ki...Fragmentation of CO in a linearly polarized femtosecond laser field within the intensity order of 10^14 W.cm^-2 at 820nm is investigated experimentally by using velocity mapping technique. According to the observed kinetic energy and angular distributions of different charged fragment ions, fragmentation channels of CO are proposed. The angular distributions provide helpful information for assigning the dissociation channels.展开更多
基金supported by the National Natural Science Foundation of China (No. 20573029)the Natural Science Foundation of Heilongjiang Province (No. B200905)
文摘Ab initio and density functional theory calculations have been carried out to investigate the reaction of hydroxyl radical （OH） and 1,1,1-trichloroethane （CH3CCl3）. The potential energy surface has been given according to the relative energies calculated at the MP2/cc-pVTZ level after the spin projection （PMP2）. Five reaction channels were identified and the intramolecular hydrogen bonding was observed in some transition state structures. The barrier heights and reaction enthalpies calculated for all possible channels show that the hydrogen abstraction channel is predominant kinetically and thermodynamically. The contribution from other channels was predicted to be minor.
基金Supported by the Science Foundation of Education Department of Heilongjiang Province(12511142)
文摘Reduction of a series of N,N＇-diaryl adipyl bis-azo compounds using hydrazine hydrate as reductant was investigated. The products were characterized by elemental analysis, IR and 1H NMR methods and confirmed to be N,N＇-diaryl adipyl dihydrazine. The results show that hydrazine hydrate can selectively reduce azo bonds with other potential reducible bonds intact in the N,N＇-diaryl adipyl bis-azo compounds. The yields are high up to 92% under mild reaction conditions. According to the previous reports, this reduction process was attributed to an indirect reduction mechanism through an intermediate diimide.
基金This work was supported by the grants from NSFC Foundations (No. 20473090 and 20633070) Foundation from Harbin Normal University (KM2005-02)
文摘The reaction mechanism of 1-chloroethane with hydroxyl radical has been investigated by using density functional theory （DFT） B3LYP/6-31G （d, p） method. All bond dissociation enthalpies were computed at the same theoretical level. It was found that hydrogen abstraction pathway is the most favorable. There are two hydrogen abstraction pathways with activation barriers of 0.630 and 4.988 kJ/mol, respectively, while chlorine abstraction pathway was not found. It was observed that activation energies have a more reasonable correlation with the reaction enthalpy changes （ΔHr） than with bond dissociation enthalpies （BDE）.
基金Supported by the National Natural Science Foundation of China under Grant Nos 20633070 and 20473090.
文摘Based on the Onion-Peeling algorithm （OPA） principle, we present a simplified model for analysing photoion and photoelectron images, which allows the analysis of experimental raw images. A three-dimensional distribution of the nascent charged particles, from which the radial and angular distributions are deduced, can be obtained more easily by this model than by the commonly used procedures. The analysis results of Xe photoelectron images by this model are compared with those from the standard Hankel-Abel inversion. The results imply that this model can be used for complicated （many peaks） and ＇ditffcult＇ （low signal-to-noise） images with cylindrical symmetries, and can provide a reliable reconstruction in some cases when the commonly used Haukel Abel transform method fails.
基金Supported by the National Natural Science Foundation of China under Grant Nos 20633070 and 20473090.
文摘Fragmentation of CO in a linearly polarized femtosecond laser field within the intensity order of 10^14 W.cm^-2 at 820nm is investigated experimentally by using velocity mapping technique. According to the observed kinetic energy and angular distributions of different charged fragment ions, fragmentation channels of CO are proposed. The angular distributions provide helpful information for assigning the dissociation channels.
