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Li X.-Y.,Beijing Institute of Fashion Technology | Feng L.-X.,Beijing Key Laboratory of Clothing Materials RandD and Assessment
Journal of Beijing Institute of Clothing Technology (Natural Science Edition) | Year: 2010

Synthesized two kinds of ionic liquid, which is 1-allyl-1-3- methylimidazolium chloride [AMIMCI] and 1-allyl-1. 3-bimethylimidazolium chloride [(MA)MIMCI], and investigated the dissolved properties of the silk fibroin in the ionic liquid. At the same time, the properties of regenerated silk fibroin were tested by X-ray diffraction, FTIR and TGA. Results showed that at the temperature of 90 °C , the maximum concentration of the silk fibroin dissolved in the two kinds of ionic liquids in 30 min could attain to 15% . After the silk being dissolved in the ionic liquid, the molecular conformation of the generation silk have not changed, the derivative reaction has not occured, but the thermal stability and thermal decomposition temperature decreased. Source

Xu S.-X.,Beijing Institute of Fashion Technology | Liu T.-Y.,Beijing Institute of Fashion Technology | Liu T.-Y.,Beijing Key Laboratory of Clothing Materials RandD and Assessment
Journal of Beijing Institute of Clothing Technology (Natural Science Edition) | Year: 2011

To study the separation and purification of polysaccharide of mulberry by strong alkalinity ion-exchange fiber on the dynamic conditions, the influences of velocity, pH value, concentration and volume of the polysaccharide solution on dynamic adsorption and desorption were investigated respectively and the dynamic adsorption activation energy was obtained. The results showed that when the initial concentration was 0. 38 mg/mL, pH value was 6, the volume was 30 mL and the velocity was 0. 5 mL/min, the activation energy was 37. 45 kJ/mol, the adsorption capacity was 232. 22 mg/ g. The optimum condition for desorption could be obtained when the desorption agent was ethanol solution which volume fraction was 60% , pH value was 1 and the volume ratio of desorption agent to the bed of fiber was 5. The method of using ion exchange fiber to extract and refine polysaccharide is feasible, which opens up a new channel and a new foundation for extracting and refining polysaccharide. Source

Li C.-J.,Beijing Institute of Fashion Technology | Li C.-J.,Beijing Key Laboratory of Clothing Materials RandD and Assessment | Xu G.-R.,Beijing Institute of Fashion Technology
Applied Surface Science | Year: 2011

TiO2 micro/nanospheres were synthesized by a combination process contains hydrolysis of titanium tetra-n-butyl in mixed solution of anhydrous ethanol/ammonia and the subsequent calcination under 550 °C for 7 h. The pH values of the mixed solution were tuned to be 10.4, 11.0 and 11.6, respectively, by adding different amounts of ammonia. Scanning electron microscope (SEM) and transmission electron microscope (TEM) were used to characterize the morphologies and the crystallinity. X-ray diffraction (XRD) patterns indicated that pH value of the precursors has an important effect on the crystal phase composition. UV-vis diffuse reflectance spectrum was applied to characterize the optical properties of samples. Degradation of methylene blue under the irradiation of 300 W Hg lamp confirmed the enhanced photocatalytic activity of TiO2 micro/nanospheres. In addition, the formation mechanism was proposed. © 2010 Elsevier B.V. All rights reserved. Source

Yan D.,Beijing University of Chemical Technology | Fan G.,Beijing University of Chemical Technology | Guan Y.,Peking University | Meng Q.,Beijing University of Chemical Technology | And 4 more authors.
Physical Chemistry Chemical Physics | Year: 2013

Tuning and controlling the solid-state luminescence of molecular solids play a key role in developing multi-color displays and tunable dye laser. In this work, we report the tunable blue and red luminescence by the formation of solvate crystals of 1,4-bis(5-phenyl-2-oxazolyl)benzene (POPOP) and 4-(dicyanomethylene)-2-methyl-6-(4-dimethylaminostyryl)-4H-pyran (DCM). Upon introduction of guest solvents (chloroform and dichloromethane) into the POPOP and DCM host matrices, the obtained solvate crystals exhibit an alternated stacking arrangement, interaction fashion, and crystal symmetry compared with the pristine chromophore solids. Furthermore, the solvates of POPOP (CCl 3H) and DCM (CCl2H2) present changeable luminescent properties (such as one-/two-photon emissive wavelength, fluorescence lifetime and photoluminescent quantum yield) in the blue/red regions relative to the pristine POPOP and DCM. In addition, the second harmonic generation can also be obtained for the DCM (CCl2H2) due to the transformation of the centrosymmetric to a non-centrosymmetric structure from pristine DCM. Periodic density functional theoretical calculations suggest that the guest solvents do not participate in the frontier orbital distribution within the solvate crystals. Therefore, by the combination of experimental and theoretical studies on the solvate crystals, this work not only reports the supramolecular assembly of new types of host-guest photoactive systems, but also provides a detailed understanding of the electronic structures of the solid-state luminescent materials. © 2013 The Owner Societies. Source

Xu G.-R.,Beijing University of Chemical Technology | Wang J.-N.,Beijing Institute of Fashion Technology | Wang J.-N.,Beijing Key Laboratory of Clothing Materials RandD and Assessment | Li C.-J.,Beijing University of Chemical Technology | And 2 more authors.
RSC Advances | Year: 2013

Binary zeolite microspheres (BZMs) with tunable hierarchical architectures, including particles (BZMs-PS, nanosheets-assembled microspheres (BZMs-NA), urchin-like microspheres with short nanorods (BZMs-US), and urchin-like microspheres with long nanorods (BZMs-UL) were prepared directly by self-crystallization via a facile and effective hydrothermal method without any additives from inorganic sources. The obtained BZMs were composed of hydroxyl sodalite (HS) and hydroxyl cancrinite (HC). The growth process of BZMs was explored and it was speculated that the tunable architecture formation was determined by the bi-phase crystallization differential. In addition, reversed crystal growth involving surface-to-core crystallization was detected, which was supposed to be the reason for the formation of hollow cores. The adsorption experiments indicated that the BZMs-NA exhibit the highest adsorption capacity of 45.6 mg g-1, and all the BZMs showed a fast adsorption rate. All the factors that might influence the adsorption abilities of the BZMs, including surface area, pore sizes, zeta potentials, and intraparticle diffusion, were investigated. The results suggested that the adsorption was predominantly affected by the surface area accompanied by the electrostatic attraction, and intraparticle diffusion was excluded. Therefore, this work provides an effective strategy for the synthesis of spherical sodalite/cancrinite materials with tunable architectures, which can potentially be used in the field of separation and catalysis. © The Royal Society of Chemistry 2013. Source

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