Beijing Key Laboratory of Clothing Materials RandD and Assessment

Beijing, China

Beijing Key Laboratory of Clothing Materials RandD and Assessment

Beijing, China
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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.


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.


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.


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.


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.


Zhang M.,Beijing Institute of Fashion Technology | Zhang M.,Beijing Key Laboratory of Clothing Materials RandD and Assessment | Wang J.,Beijing Institute of Fashion Technology | Wang J.,Beijing Key Laboratory of Clothing Materials RandD and Assessment | And 2 more authors.
Polymer Engineering and Science | Year: 2015

A new thin film nanofibrous composite (TFNC) membrane for Cr (VI) removal was prepared by layer-by-layer assembly of chitosan/alginate on the surface of the electrospinning nanofibrous substrates. Scanning electron microscopy and static contact angle measurement were applied to characterize surface morphology and hydrophilicity, respectively. The mechanism of Cr (VI) removal and some factors, including positive/negative charge of terminating layer, bilayers, and Cr (VI) concentration, were investigated by a dead-end filter. These TFNC membranes exhibited a high Cr (VI) removal efficiency and an advantage of saving energy (the operating pressure was only 0.7 bar). The high efficiency was supposed to be the adsorption and Donnan effect which acted simultaneously for Cr (VI) removal. Besides, the research of recyclable property indicated that these TFNC membranes were easily regenerated and had a stable recycle property. Additionally, simple fabrication, low cost, and abundant species of polyelectrolytes showed these membranes had a good potential in heavy metal removal. © 2014 Society of Plastics Engineers.


Li X.-Y.,Beijing Institute of Fashion Technology | Wang J.-N.,Beijing Institute of Fashion Technology | Wang J.-N.,Beijing Key Laboratory of Clothing Materials RandD and Assessment | Zhang L.-L.,Beijing Institute of Fashion Technology | And 3 more authors.
Journal of Materials Science | Year: 2012

A novel magnetically separable composite photocatalyst-〈La-doped TiO 2〉/CoFe 2O 4 nanofiber-was prepared by a two-spinneret electrospinning method combined with sol-gel method. The nanofibers were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscope (TEM), Energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), and vibrating sample magnetometer (VSM). It was shown that the diameter of 〈1.0% La-doped TiO 2〉/CoFe 2O 4 nanofibers was 100-150 nm after calcination at 600 °C for 2 h. EDS and XPS measurements on the photocatalytic material indicated the existence of La 3+ oxidation states in 〈1.0% La-doped TiO 2〉/CoFe 2O 4 nanofibers. The photocatalytic activity of as-prepared nanofibers was evaluated using methylene blue (MB) as a model organic compound and the result revealed that the 〈1.0% La-doped TiO 2〉/CoFe 2O 4 nanofibers have an efficient photocatalytic property, and the degradation rate of MB could reach 93% in 150 min. Moreover, the magnetic property of the nanofibers has also been characterized, and the nanofibers show a good magnetic response, which indicates that the possibility of the magnetic nanofibers' potential recycling property. © 2011 Springer Science+Business Media, LLC.


Li C.-J.,Beijing Institute of Fashion Technology | Li C.-J.,Beijing Key Laboratory of Clothing Materials RandD and Assessment | Huang B.-N.,Beijing Institute of Fashion Technology | Huang B.-N.,Beijing Key Laboratory of Clothing Materials RandD and Assessment | And 2 more authors.
Journal of Materials Science | Year: 2013

BaFe12-x Al x O19 nanofibers (x = 0-2.0) with average diameter 110 nm have been prepared via the electrospinning and subsequent heat treatment at 1100 C for 2 h. Individual BaFe12O 19 nanofibers were composed of numerous nanocrystallites stacking alternatively along the long axis of fiber and the single crystallites on each nanofibers had random orientations. With increasing Al3+ ions substitution contents from 0 to 2.0, the diameter and morphology of nanofibers were almost no change. However, the lattice parameters decreased due to Fe 3+ ions substituted by smaller Al3+ ions and the average grain size calculated by the Scherrer's equation reduced from 47 to 42 nm. The crystallites possessed a hexagonal plate-like shape at x = 0 while they became rod-like with various Al3+ ions substitution. The X-ray diffraction patterns show that single-phase barium hexaferrite was formed when Al 3+ ions substitution contents were less than and equal to 1.0, while other impurity phases were detected when they were more than 1.0. The chemical analysis shows that the element Al was all incorporated into the lattice of BaFe12O19 and evenly distributed throughout the BaFe 12-x Al x O19 nanofibers. The magnetic testing shows that the saturation magnetization (M s) decreased obviously from 63.92 to 29.70 A m2/kg, while coercivity (H c) increased significantly from 288.2 to 740.7 kA/m with increasing Al3+ ions substitution. © 2012 Springer Science+Business Media New York.


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.
Applied Surface Science | Year: 2013

TiO2 nanomaterials with tunable morphologies including nanotubes, nanofibers-nanoparticles, and nanoparticles were fabricated using electrospun nanofibers as the template and ammonium as the additives. The morphologies and the crystallization of the obtained samples were characterized by scanning electron microscope (SEM) and X-ray diffraction (XRD), respectively. The formation mechanism was explored and it was supposed that the formation of tunable morphologies of the samples was realized by the hydrogen bonding interaction between the TiO2 precursor and the nanofibers, which can be modulated by the ammonium. The photocatalytic activities of the samples obtained under different circumstances were invested by degradation of Methylene Blue (MB) under the irradiation of mercury lamp of 300 W. The morphologies are in close relation with the photocatalytic activities. The nanotubes and nanoparticles exhibit similar and higher photocatalytic activities while the nanofibers-nanoparticles composites show lower one. The research work can provide some fundamental research for the photocatalysis area. Additionally, the fabrication method adopted here seems to be simple and can be easily extended to prepare other semiconductor materials. © 2013 Published by Elsevier B.V.


Li C.-J.,Beijing Institute of Fashion Technology | Li C.-J.,Beijing Key Laboratory of Clothing Materials RandD and Assessment | Wang B.,Beijing Institute of Fashion Technology | Wang B.,Beijing Key Laboratory of Clothing Materials RandD and Assessment | And 2 more authors.
Journal of Magnetism and Magnetic Materials | Year: 2012

Ba (1-x)La xFe 12O 19 (0.00≤x≤0.10) nanofibers were fabricated via the electrospinning technique followed by heat treatment at different temperatures for 2 h. Various characterization methods including scanning electron microscopy (SEM), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), and microwave vector network analyzer were employed to investigate the morphologies, crystalline phases, magnetic properties, and complex electromagnetic parameters of nanofibers. The SEM images indicate that samples with various values of x are of a continuous fiber-like morphology with an average diameter of 110±20 nm. The XRD patterns show that the main phase is M-type barium hexaferrite without other impurity phases when calcined at 1100 °C. The VSM results show that coercive force (H c) decreases first and then increases, while saturation magnetization (M s) reveals an increase at first and then decreases with La 3 ions content increase. Both the magnetic and dielectric losses are significantly enhanced by partial substitution of La 3 for Ba 2 in the M-type barium hexaferrites. The microwave absorption performance of Ba 0.95La 0.05Fe 12O 19 nanofibers gets significant improvement: The bandwidth below -10 dB expands from 0 GHz to 12.6 GHz, and the peak value of reflection loss decreases from -9.65 dB to -23.02 dB with the layer thickness of 2.0 mm. © 2011 Elsevier B.V. All rights reserved.

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