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Ding J.,Changzhou University | Yuan L.,Jiangsu University | Gao L.,Yancheng Entry Exit Inspection and Quarantine Bureau | Chen J.,Yancheng Institute of Technology
Journal of Luminescence | Year: 2012

A new rhodamine derivative (RhB-Im) was synthesized as an on-off chemosensor for Cu 2+ in an acidic aqueous solution. RhB-Im exhibited chemically reversible and highly selective and sensitive fluorescence response toward Cu 2+ in aqueous acetate-buffer/DMF solution (pH 3.6) over other competitive metal ions. Upon addition of Cu 2+, RhB-Im displayed remarkable fluorescence quenching accompanied by a clear color change from pink to red. Based on the analysis of Stern-Volmer plots, a static quenching mode was proposed to be primarily responsible for the fluorescence quenching event when the concentration of Cu 2+ was low, but, the energy- and electron-transfer processes cannot be ruled out. © 2012 Elsevier B.V. All rights reserved.

Xu S.,Nanjing University of Science and Technology | Liu D.-B.,Nanjing University of Science and Technology | Wang X.-F.,Xian Modern Chemistry Research Institute | Wang J.-L.,Xian Modern Chemistry Research Institute | And 2 more authors.
Tuijin Jishu/Journal of Propulsion Technology | Year: 2011

External fire tests were performed to determine the applicability of heat flux estimation method to propellants. The heat fluxes of three propellants were measured by a radiometer and calculated through the estimation method respectively. The average values of measured heat fluxes were 2.87kW/m2, 2.65kW/m2 and 3.44kW/m2, while the corresponding calculated values were 4.06kW/m2, 7.62kW/m2 and 3.67kW/m2. The results show that, as the burning time is greater than 5s, the calculated heat flux is in accordance with the measured value; and as the burning time is less than or equal to 5s, measuring the heat flux by radiometer is proposed, because the ratio of radiant heat to combustion heat used in estimation method (0.33) is greater than the actual ratio, and it will lead an abnormal calculated value.

Liu S.,Jiangsu University | Pan J.,Jiangsu University | Cao J.,Yancheng Entry Exit Inspection and Quarantine Bureau | Dai X.,Jiangsu University | And 4 more authors.
Chemical Engineering Journal | Year: 2016

A hierarchical porous PUPDAMSNs sponge with reversible "shape memory" effect was employed in this investigation for the simultaneous adsorption of Pb(II) and 2,4,6-trichlorophenol (TCP). Our strategy was based on facile conjugation of carboxyl groups modified mesoporous silica nanoparticles (MSNs) to poly(dopamine) (PDA) coated polyurethane (PU) sponge (PUPDA), and the as-prepared PUPDAMSNs sponge possessed the advantages of less operation time, convenient adsorbent collection and regeneration owing to its reversible "shape memory" effect. In single system, Pb(II) and TCP adsorption were implemented at pH=6.0, and their max monolayer adsorption amount at 298k were 104.2mgg-1 and 184.2mgg-1, respectively. However, the binary system exhibited that the coexistence of Pb(II) and TCP could obviously accelerate jointly adsorption at low concentrations, due to partial complexation between Pb(II) and TCP during the 10-30mgL-1 of Pb(II) and TCP. While at higher concentrations, TCP adsorption was inhibited in relation to the competition from Pb(II), but Pb(II) adsorption was scarcely affected due to its smaller size and strong complexation with amino groups from PUPDAMSNs sponge. The PUPDA sponge could be simply recycled and maintained stability after seven adsorption/desorption cycles in the regeneration steps. © 2015.

Yin Y.,Jiangsu University | Pan J.,Jiangsu University | Cao J.,Yancheng Entry Exit Inspection and Quarantine Bureau | Ma Y.,Jiangsu University | And 5 more authors.
Chemical Engineering Journal | Year: 2016

Herein we reported a novel method for preparation of hybrid molecularly imprinted polymer foams (MIPFs) via a twice imprinting strategy. Firstly, based on halloysite nanotubes (HNTs) cores, three molecularly imprinted nanomaterials (MIPs-S, MIPs-M and MIPs-L) with controlled thickness of imprinted shells (i.e., 7.0. nm, 17. nm and 36. nm, respectively), were prepared by precipitation polymerization. The surface hydrophobicity of MIP nanomaterials gradually enhanced with the increasing thickness of imprinted shells. Secondly, three hybrid MIP foams (MIPFs-S, MIPFs-M, MIPFs-L) were successively fabricated by W/O Pickering high internal phase emulsions (HIPEs) template stabilized by the corresponding MIPs nanomaterials. Due to the increased hydrophobicity of the MIPs nanomaterials, the amount of interconnecting pores in hybrid MIPFs was continuously decreased until a closed-cell structure appeared, while the average void diameter increased from 10. μm to 28. μm. Binding experiments demonstrated that optimized hybrid MIP foams (MIPFs-M) possessed enhanced adsorption capacity, fast kinetics and excellent recognition ability towards λ-cyhalothrin (LC). Therefore, this two-step imprinting strategy could not only figure out the difficulty in solid-liquid phase separation and the recycling of nano-sized MIPs but also overcome the disadvantage of stabilizing solid particles on the surface of MIPFs referring to the lack of specific adsorption activity. © 2015 Elsevier B.V.

Pan J.,Jiangsu University | Qu Q.,Jiangsu University | Cao J.,Yancheng Entry Exit Inspection and Quarantine Bureau | Yan D.,Jiangsu University | And 3 more authors.
Chemical Engineering Journal | Year: 2014

The water-in-oil Pickering high internal phase emulsions (HIPEs) were firstly stabilized by hydrophobic silica particles with adding small amounts of nonionic surfactant Hypermer 2296. Then molecularly imprinted polymer foams (MIPFs) derived from Pickering HIPEs were evaluated as adsorbents for the selective adsorption of λ-cyhalothrin. The results of characterization indicated that MIPFs possessed open-cell structure, interconnecting pores, thermal stability, moderate hydrophobicity and mechanical robust. The adsorption capacity for λ-cyhalothrin were closely related with the morphologies of the MIPFs, such as void diameter and interconnectivity, which could be easily tailored by varying the parameters of Pickering HIPEs. The batch mode experiments proved that as-prepared MIPFs exhibited the excellent adsorption capacity for λ-cyhalothrin (46.10μmolg-1 at 25°C) and enhanced recognition towards λ-cyhalothrin over fenvalerate and diethyl phthalate. © 2014 Elsevier B.V.

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