三维石墨烯气凝胶具有可调控的孔结构、大的比表面积、优异的压缩性、弹性和润湿性,是一种高效的油水分离吸附剂。然而,三维石墨烯气凝胶的制备方法通常包括高温过程,导致高成本、能耗高和耗时长。本文以磷钼酸为交联剂和促进剂,水合肼...三维石墨烯气凝胶具有可调控的孔结构、大的比表面积、优异的压缩性、弹性和润湿性,是一种高效的油水分离吸附剂。然而,三维石墨烯气凝胶的制备方法通常包括高温过程,导致高成本、能耗高和耗时长。本文以磷钼酸为交联剂和促进剂,水合肼为还原剂,在室温条件下同时将氧化石墨烯还原与自组装,制备出三维多孔的多金属氧酸盐复合石墨烯气凝胶(POM-GA),并证明其是一种高效、可回收的油水分离吸收剂。研究表明,POM-GA具有三维连通的多孔结构、大的比表面积、优异的压缩性、弹性和润湿性,对不同的有机溶剂具有良好的吸附能力(100~210 g g^−1),可快速去除水中的各种有机污染物,优于先前报道的大多数高温合成的石墨烯基宏观组装体。经10次吸附-挤压和吸附-挤压-燃烧循环后,POM-GA的吸油量保持率分别达到96%和90%。因此,三维POM-GA具有广泛的适用性和优异的耐用性,在高效油水分离方面具有良好的应用前景。展开更多
Preparation of photocatalytic regenerationable activated carbon (AC) is the key step for the practical application of in situ regeneration of exhausted AC. A novel photocatalytic regenerationable AC was prepared by ...Preparation of photocatalytic regenerationable activated carbon (AC) is the key step for the practical application of in situ regeneration of exhausted AC. A novel photocatalytic regenerationable AC was prepared by sol-gel TiO2 in this work. The adsorption and regeneration performance of TiO2/AC were evaluated using phenol as model compound. Scanning electron microscope (SEM) and nitrogen (77 K) adsorption isotherm were used to determine the surface area, pore structure and the distribution of TiO2. The results showed that with the increase of TiO2 loading, adsorption capacity of TiO2/AC decreased and the regeneration efficiency increased. The photocatalytic regenerationable AC with suitable TiO2 loading (2 wt%) exhibited suitable adsorption capacity and regeneration efficiency. TiO2 located mainly in the entrance of macro-pore of carbon. The prepared TiO2/AC exhibited similar surface structure and pore structure with material carbon.展开更多
Raman spectra and ultraviolet-visible(UV-Vis) absorption spectra of linear polyene molecule-canthaxan-thin in n-hexane are measured and analyzed.In addition,the optimized structure of canthaxanthin was calculated vi...Raman spectra and ultraviolet-visible(UV-Vis) absorption spectra of linear polyene molecule-canthaxan-thin in n-hexane are measured and analyzed.In addition,the optimized structure of canthaxanthin was calculated via density functional theory(DFT) functional B3LYP.With decreasing the concentration,Raman scattering cross section (RSCS) of fundamental frequency is extremely high,and the UV-Vis absorption bands become narrower.The results of coherent weakly damped electron-Lattice vibration model were analyzed.展开更多
We theoretically and experimentally study the relationship between Fermi resonance and solvent effects and investigate the Fermi resonance of p-benzoquinone and cyclopentanone in different solvents and the Fermi reson...We theoretically and experimentally study the relationship between Fermi resonance and solvent effects and investigate the Fermi resonance of p-benzoquinone and cyclopentanone in different solvents and the Fermi resonance of CS_(2)in C_(6)H_(6)at different concentrations.Also,we investigate the Fermi resonance of C_(6)H_(6)and CCl_(4)in their solution at different pressures.It is found that solvent effects can be utilized to search Fermi resonance parameters such as coupling coefficient and spectral intensity ratio,etc.,on the other hand,the mechanism of solvent effects can be revealed according to Fermi resonance at high pressure.展开更多
We have determined the Raman scattering cross sections(RSCSs) of fl-carotene for C=C and C-C stretching modes, with the 1444 cm^-1 Raman band of cyclohexane as internal standard, in different solvents at low concent...We have determined the Raman scattering cross sections(RSCSs) of fl-carotene for C=C and C-C stretching modes, with the 1444 cm^-1 Raman band of cyclohexane as internal standard, in different solvents at low concentrations by measuring Raman intensity. The results show that RSCSs of β-carotene were 10^6-10^7 times larger than the general RSCSs, we analyzed that this enhancement was caused not only by the resonance Raman effect but also by nonlinear coherent CC vibration in aqueous β-carotene. Moreover, overtone and combinations of it were also observed and their intensities were 10%-20% of those of their fundamentals when β-carotene was dissolved in non-polar solvents, respectively.展开更多
The two-photon absorption(TPA)and TPA-induced frequency upconversion emission properties of the dyes 4-[P-(dicyanoethylamino)crystal]-N-methypyrdinium iodide and the complex of 4-[P-(dicyanoethylamino)crystal]-N...The two-photon absorption(TPA)and TPA-induced frequency upconversion emission properties of the dyes 4-[P-(dicyanoethylamino)crystal]-N-methypyrdinium iodide and the complex of 4-[P-(dicyanoethylamino)crystal]-N-methypyrdinium iodide and Ce(NO3)3 were experimentally studied.It was found that the TPA cross section for the dye sensitized by Ce3+ is two factors larger than that of the dye without being sensitized.A three-level system model of the dye molecules was used to analyze the enhancement of TPA by the sensitizer Ce3+,which indicated that the sensitizer results in the increase of the transition dipole moment from the one-photon allowed excited state(1Bu)to the two-photon allowed excited state(2Ag).展开更多
文摘三维石墨烯气凝胶具有可调控的孔结构、大的比表面积、优异的压缩性、弹性和润湿性,是一种高效的油水分离吸附剂。然而,三维石墨烯气凝胶的制备方法通常包括高温过程,导致高成本、能耗高和耗时长。本文以磷钼酸为交联剂和促进剂,水合肼为还原剂,在室温条件下同时将氧化石墨烯还原与自组装,制备出三维多孔的多金属氧酸盐复合石墨烯气凝胶(POM-GA),并证明其是一种高效、可回收的油水分离吸收剂。研究表明,POM-GA具有三维连通的多孔结构、大的比表面积、优异的压缩性、弹性和润湿性,对不同的有机溶剂具有良好的吸附能力(100~210 g g^−1),可快速去除水中的各种有机污染物,优于先前报道的大多数高温合成的石墨烯基宏观组装体。经10次吸附-挤压和吸附-挤压-燃烧循环后,POM-GA的吸油量保持率分别达到96%和90%。因此,三维POM-GA具有广泛的适用性和优异的耐用性,在高效油水分离方面具有良好的应用前景。
基金The National Natural Science Foundation of China (No. 30400339) and the Heilongjiang Province Natural Science Foundation(No.C2004-29)
文摘Preparation of photocatalytic regenerationable activated carbon (AC) is the key step for the practical application of in situ regeneration of exhausted AC. A novel photocatalytic regenerationable AC was prepared by sol-gel TiO2 in this work. The adsorption and regeneration performance of TiO2/AC were evaluated using phenol as model compound. Scanning electron microscope (SEM) and nitrogen (77 K) adsorption isotherm were used to determine the surface area, pore structure and the distribution of TiO2. The results showed that with the increase of TiO2 loading, adsorption capacity of TiO2/AC decreased and the regeneration efficiency increased. The photocatalytic regenerationable AC with suitable TiO2 loading (2 wt%) exhibited suitable adsorption capacity and regeneration efficiency. TiO2 located mainly in the entrance of macro-pore of carbon. The prepared TiO2/AC exhibited similar surface structure and pore structure with material carbon.
基金Supported by the National Natural Science Foundation of China(No.10974067)the Natural Science Foundation of Jilin Province,China(No.20101508)the Technology Development Projects of Jilin Province,China(No.20090534)
文摘Raman spectra and ultraviolet-visible(UV-Vis) absorption spectra of linear polyene molecule-canthaxan-thin in n-hexane are measured and analyzed.In addition,the optimized structure of canthaxanthin was calculated via density functional theory(DFT) functional B3LYP.With decreasing the concentration,Raman scattering cross section (RSCS) of fundamental frequency is extremely high,and the UV-Vis absorption bands become narrower.The results of coherent weakly damped electron-Lattice vibration model were analyzed.
基金Supported by the National Natural Science Foundation of China under Grant Nos 10774057 and 10974067.
文摘We theoretically and experimentally study the relationship between Fermi resonance and solvent effects and investigate the Fermi resonance of p-benzoquinone and cyclopentanone in different solvents and the Fermi resonance of CS_(2)in C_(6)H_(6)at different concentrations.Also,we investigate the Fermi resonance of C_(6)H_(6)and CCl_(4)in their solution at different pressures.It is found that solvent effects can be utilized to search Fermi resonance parameters such as coupling coefficient and spectral intensity ratio,etc.,on the other hand,the mechanism of solvent effects can be revealed according to Fermi resonance at high pressure.
基金Supported by the National Natural Science Foundation of China(No.10774057)the Foundation of Jilin Provincial Science & Technology Department,China(No.20090534)the Opened Fund of State Key Laboratory of Integrated Optoelectronics, China(No.IOSKL-KF200908)
文摘We have determined the Raman scattering cross sections(RSCSs) of fl-carotene for C=C and C-C stretching modes, with the 1444 cm^-1 Raman band of cyclohexane as internal standard, in different solvents at low concentrations by measuring Raman intensity. The results show that RSCSs of β-carotene were 10^6-10^7 times larger than the general RSCSs, we analyzed that this enhancement was caused not only by the resonance Raman effect but also by nonlinear coherent CC vibration in aqueous β-carotene. Moreover, overtone and combinations of it were also observed and their intensities were 10%-20% of those of their fundamentals when β-carotene was dissolved in non-polar solvents, respectively.
基金Supported by the National Natural Science Foundation of China(No.10074020).
文摘The two-photon absorption(TPA)and TPA-induced frequency upconversion emission properties of the dyes 4-[P-(dicyanoethylamino)crystal]-N-methypyrdinium iodide and the complex of 4-[P-(dicyanoethylamino)crystal]-N-methypyrdinium iodide and Ce(NO3)3 were experimentally studied.It was found that the TPA cross section for the dye sensitized by Ce3+ is two factors larger than that of the dye without being sensitized.A three-level system model of the dye molecules was used to analyze the enhancement of TPA by the sensitizer Ce3+,which indicated that the sensitizer results in the increase of the transition dipole moment from the one-photon allowed excited state(1Bu)to the two-photon allowed excited state(2Ag).