This study deals with the enhanced solubilization of polycyclic aromatic hydrocarbons (PAHs) such as phenanthrene (PHE) and fluorene (FLR) in a pure cationic gemini (G6) and three conventional surfactants [pol...This study deals with the enhanced solubilization of polycyclic aromatic hydrocarbons (PAHs) such as phenanthrene (PHE) and fluorene (FLR) in a pure cationic gemini (G6) and three conventional surfactants [polyethylene glycol dodecyl ether (Brij35), cetyltrimethyl ammonium bromide (CRAB) and sodium lauryl sulfate (SDS)] as well as in their equimolar binary combinations (G6-Brij35, G6-CTAB and G6-SDS). Their solubilization efficiency toward PHE and FLR has been quantified in terms of the molar solubilization ratio (MSR) and the micelle-water partition coefficient (Kin). The ideality/nonideality of the mixed micelles is discussed with the help of Clint, Rubingh and Rosen's approaches. These theories determine the deviation of experimental critical micelle concen- tration (CMC) values from ideal critical micelle concentration, which was measured by evaluating the interaction parameters (/3m and/3). Negative values ofβm were observed in all the equimolar binary systems, which show synergism in the mixed micelles. Whereas at air/liquid interface synergism was observed in the systems G6-CrAB and G6-Brij35; G6-SDS exhibited an antagonistic effect. The order of MSR and Km was G6-CTAB 〉 G6- Brij35 〉 G6-SDS for phenanthrene as well as for fluorene.展开更多
By numerically solving the Maxwell-Bloch equations using an iterative predictor-corrector finite-difference time-domain technique, we investigate propagating properties of a few-cycle laser pulse in a 4,4'-bis(di-n-...By numerically solving the Maxwell-Bloch equations using an iterative predictor-corrector finite-difference time-domain technique, we investigate propagating properties of a few-cycle laser pulse in a 4,4'-bis(di-n-butylamino) stilbene (BDBAS) molecular medium when a static electric field exists. Dynamical two-photon absorption (TPA) cross sections are obtained and optical limiting (OL) behavior is displayed. The results show that when the static electric field intensity increases, the dynamical TPA cross section is enhanced and the OL behavior is improved. Moreover, both even- and odd-order harmonic spectral components are generated with existence of the static electric field because it breaks the inversion symmetry of the BDBAS molecule. This work provides a method to modulate the nonlinear optical properties of the BDBAS compounds.展开更多
The excited-state double proton transfer(ESDPT)properties of 1,5-dihydroxyanthraquinone(1,5-DHAQ)in various solvents were investigated using femtosecond transient absorption spectroscopy and the DFT/TDDFT method.The s...The excited-state double proton transfer(ESDPT)properties of 1,5-dihydroxyanthraquinone(1,5-DHAQ)in various solvents were investigated using femtosecond transient absorption spectroscopy and the DFT/TDDFT method.The steady-state fluorescence spectra in toluene,tetrahydrofuran(THF)and acetonitrile(ACN)solvents presented that the solvent polarity has an effect on the position of the ESDPT fluorescence emission peak for the 1,5-DHAQ system.Transient absorption spectra show that the increasing polarity of the solvent accelerates the rate of excited state dynamics.Calculated potential energy curves analysis further verified the experimental results.The ESDPT barrier decreases gradually with the increase of solvent polarity from toluene,THF to ACN solvent.It is convinced that the increase of solvent polarity can promote the occurrence of the ESDPT dynamic processes for the 1,5-DHAQ system.This work clarifies the mechanism of the influence of solvent polarity on the ESDPT process of 1,5-DHAQ,which provides novel ideas for design and synthesis of new hydroxyanthraquinone derivatives.展开更多
Reaction of unique [W(CN)6(phen)]- with a magnetically anisotropic Mn Schiff base yielded a wv(5d)-Mnm(3d) bimetallic compound with a linear chain structure. The magnetic properties of the chain complex featur...Reaction of unique [W(CN)6(phen)]- with a magnetically anisotropic Mn Schiff base yielded a wv(5d)-Mnm(3d) bimetallic compound with a linear chain structure. The magnetic properties of the chain complex feature a ferrimagnetic behavior as well as slow magnetic relaxation typical for a single-chain magnet.展开更多
文摘This study deals with the enhanced solubilization of polycyclic aromatic hydrocarbons (PAHs) such as phenanthrene (PHE) and fluorene (FLR) in a pure cationic gemini (G6) and three conventional surfactants [polyethylene glycol dodecyl ether (Brij35), cetyltrimethyl ammonium bromide (CRAB) and sodium lauryl sulfate (SDS)] as well as in their equimolar binary combinations (G6-Brij35, G6-CTAB and G6-SDS). Their solubilization efficiency toward PHE and FLR has been quantified in terms of the molar solubilization ratio (MSR) and the micelle-water partition coefficient (Kin). The ideality/nonideality of the mixed micelles is discussed with the help of Clint, Rubingh and Rosen's approaches. These theories determine the deviation of experimental critical micelle concen- tration (CMC) values from ideal critical micelle concentration, which was measured by evaluating the interaction parameters (/3m and/3). Negative values ofβm were observed in all the equimolar binary systems, which show synergism in the mixed micelles. Whereas at air/liquid interface synergism was observed in the systems G6-CrAB and G6-Brij35; G6-SDS exhibited an antagonistic effect. The order of MSR and Km was G6-CTAB 〉 G6- Brij35 〉 G6-SDS for phenanthrene as well as for fluorene.
文摘By numerically solving the Maxwell-Bloch equations using an iterative predictor-corrector finite-difference time-domain technique, we investigate propagating properties of a few-cycle laser pulse in a 4,4'-bis(di-n-butylamino) stilbene (BDBAS) molecular medium when a static electric field exists. Dynamical two-photon absorption (TPA) cross sections are obtained and optical limiting (OL) behavior is displayed. The results show that when the static electric field intensity increases, the dynamical TPA cross section is enhanced and the OL behavior is improved. Moreover, both even- and odd-order harmonic spectral components are generated with existence of the static electric field because it breaks the inversion symmetry of the BDBAS molecule. This work provides a method to modulate the nonlinear optical properties of the BDBAS compounds.
基金supported by the National Basic Research Program of China(No.2019YFA0307701)the National Natural Science Foundation of China(No.11874180)the Young and Middle-aged Scientific and Technological Innovation leaders and Team Projects in Jilin Province(No.20200301020RQ)。
文摘The excited-state double proton transfer(ESDPT)properties of 1,5-dihydroxyanthraquinone(1,5-DHAQ)in various solvents were investigated using femtosecond transient absorption spectroscopy and the DFT/TDDFT method.The steady-state fluorescence spectra in toluene,tetrahydrofuran(THF)and acetonitrile(ACN)solvents presented that the solvent polarity has an effect on the position of the ESDPT fluorescence emission peak for the 1,5-DHAQ system.Transient absorption spectra show that the increasing polarity of the solvent accelerates the rate of excited state dynamics.Calculated potential energy curves analysis further verified the experimental results.The ESDPT barrier decreases gradually with the increase of solvent polarity from toluene,THF to ACN solvent.It is convinced that the increase of solvent polarity can promote the occurrence of the ESDPT dynamic processes for the 1,5-DHAQ system.This work clarifies the mechanism of the influence of solvent polarity on the ESDPT process of 1,5-DHAQ,which provides novel ideas for design and synthesis of new hydroxyanthraquinone derivatives.
基金supported by the National Research Foundation of Korea Funded by the Korean Government (2011-0003264)by the Priority Research Centers Program through the National Research Foundation of Korea (NRF) Funded by the Ministry of Education, Science and Technology (NRF20110018396)
文摘Reaction of unique [W(CN)6(phen)]- with a magnetically anisotropic Mn Schiff base yielded a wv(5d)-Mnm(3d) bimetallic compound with a linear chain structure. The magnetic properties of the chain complex feature a ferrimagnetic behavior as well as slow magnetic relaxation typical for a single-chain magnet.