An energy distribution theory was presented based on regular evolvement of energy fraction of acous-tic signals with fluidization velocity. Wavelet packet analysis was used in processing the acoustic sig-nals originat...
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An energy distribution theory was presented based on regular evolvement of energy fraction of acous-tic signals with fluidization velocity. Wavelet packet analysis was used in processing the acoustic sig-nals originated from particle impact on the wall of a fluidized bed. A new criterion of judging incipient fluidization(Umf) velocity and minimum turbulent velocity(Umt) was proposed according to the energy distribution theory. Experiments were performed with five groups of high density polyethylene(PE) particles and one bimodal PE to acquire incipient fluidization velocity and minimum turbulent velocity by using the criterion. The feasibility of this method in obtaining characteristic fluidization parameters was further verified by comparing it to results from the pressure drop method and the empirical value from industry.
Various novel double metal cyanide （DMC） catalysts were successfully prepared by modifying the central metal （M） and one of cyanide ion （CN-） in Zna[M（CN）b]c complex. Such modifications have significant impact...
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Various novel double metal cyanide （DMC） catalysts were successfully prepared by modifying the central metal （M） and one of cyanide ion （CN-） in Zna[M（CN）b]c complex. Such modifications have significant impact on the catalytic efficiency as well as the polymer selectivity for the reaction of PO/CO2. Zn-Ni（Ⅱ） DMC is a potential catalyst for alternating copolymerization of PO/CO2,and DMC catalysts based on Zn3[Co（CN）5X]2 （X = Br^- and N3^-） exhibit moderate efficiency for the production of *** research presents the preliminary exploration of novel DMC complex via chemical modification of its central metal and ligand.
Back Cover: Poly[2,7‐(9,9‐dihexylfluorene)]‐ block ‐poly‐(methyl methacrylate) (PF‐ b ‐PMMA) electrospun fibers formed various PF‐aggregated structures of dotlike, linelike, and ellipselike shape for different...
Back Cover: Poly[2,7‐(9,9‐dihexylfluorene)]‐ block ‐poly‐(methyl methacrylate) (PF‐ b ‐PMMA) electrospun fibers formed various PF‐aggregated structures of dotlike, linelike, and ellipselike shape for different THF/DMF solvent ratios, which led to distinct photophysical properties. Further details can be found in the article by C.‐C. Kuo, Y‐C. Tung, C.‐H. Lin, and W.‐C. Chen * on page 1711.
Cover: The cover shows the variation in refractive index of acrylic polymer‐titania hybrid films as a function of the titania content, along with a high‐resolution TEM image of the nanocrystalline domain in the hybr...
Cover: The cover shows the variation in refractive index of acrylic polymer‐titania hybrid films as a function of the titania content, along with a high‐resolution TEM image of the nanocrystalline domain in the hybrid film. Further details can be found in the article by H.‐W. Su and W.‐C. Chen on page 1778.
A novel geminal imidazolium ionic liquid with long hydrocarbon group, 1,4-bis （3-tetradecylimidazolium- 1-yl） butane bromide was synthesized and an efficient synthesized method was introduced detailedly. Its structu...
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A novel geminal imidazolium ionic liquid with long hydrocarbon group, 1,4-bis （3-tetradecylimidazolium- 1-yl） butane bromide was synthesized and an efficient synthesized method was introduced detailedly. Its structure was determined by FT-IR, ^1H NMR and elemental analysis.
PU/PMMA hybrid particles are synthesized by using the method of two-step miniemulsion polymerization. In the first step, PU prepolymer is synthesized by isophorone diisocyanates (IPDI) and poly(propylene glycol) (PPG)...
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PU/PMMA hybrid particles are synthesized by using the method of two-step miniemulsion polymerization. In the first step, PU prepolymer is synthesized by isophorone diisocyanates (IPDI) and poly(propylene glycol) (PPG) with methyl methacrylate (MMA) as a solvent. Then the oil phase, including the NCO-terminated prepolymer, MMA, hexadecane (HD), a chain extender as 1,4-butanediol (BD) or bisphenol A (BisA), a cross-linking agent trimethylol propane (TMP), and a catalyst dibutyltin dilaurate (SnDBL) is dispersed in the water phase containing SDS. Then the mixtures form miniemulsion by ultrasonication. Two kinds of initiators, BPO and KPS, are applied for the polymerization of MMA. The influences of chain extenders, initiators and PU/MMA weight ratios on the morphology of PU/PMMA latex particles are investigated. Conversion of MMA is measured and discussed. Particle sizes are analyzed by dynamic lighting scattering (DLS) and transmission electron microscopy (TEM). The cross section morphology of the hybrid particles is also characterized by TEM. For BD/BPO and BD/KPS systems, when increasing the load of PU component, PU-rich phase is moved to the outside of hybrid particles. A core-shell structure can be observed. However, for BisA/KPS system, while using hydrophobic bisphenol A as chain extender of PU, the boundary of PMMA and PU phases is not clear. A more homogeneous structure of hybrid particles is obtained.
A preparation manner for monodispersed polystyrene(PS)nanoparticles polymerized by using a novel addition procedure of a monomer is *** systems containing a smaller amount of surfactant compared with conventional micr...
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A preparation manner for monodispersed polystyrene(PS)nanoparticles polymerized by using a novel addition procedure of a monomer is *** systems containing a smaller amount of surfactant compared with conventional microemulsion polymerization,the polymerization processes consists of three stages:adding dropwise the first part of the monomer for a few minutes at 80℃ and polymerizing for 1 h;adding collectively the residual part of the monomer and polymerizing at the same temperature for another 1 h;and then polymerizing at 85℃ for another 1 *** on discussions on the nucleation mechanism of particles in the polymerization system,the influences of monomer weight added dropwise,and amounts of initiator and emulsifier on the size and distribution of PS particles were *** nanoparticles with smaller diameter such as a number-average diameter of 18.7 nm and better monodispersity were obtained since the dropped styrene amount was suitable under 20wt-% emulsifier amount and 3wt-% initiator amount based on the monomer.
We consider electron transport through a mobile island (i.e., a nanomechanical oscillator) which can accommodate one or two excess electrons and show that, in contrast to immobile islands, the Coulomb blockade peaks, ...
We consider electron transport through a mobile island (i.e., a nanomechanical oscillator) which can accommodate one or two excess electrons and show that, in contrast to immobile islands, the Coulomb blockade peaks, associated with the first and second electrons entering the island, have different functional dependences on the nano-oscillator parameters when the island coupling to its leads is asymmetric. In particular, the conductance for the second electron (i.e., when the island is already charged) is greatly enhanced in comparison to the conductance of the first electron in the presence of an external electric field. We also analyze the temperature dependence of the two conduction peaks and show that these exhibit different functional behaviors.
Cover: A three‐dimensional biocomposite scaffold of hydroxyapatite with electrospun nanofibers of chitosan (or N ‐carboxyethyl chitosan)/poly(vinyl alcohol) (CS or CECS/PVA) is prepared by a mineralization approach ...
Cover: A three‐dimensional biocomposite scaffold of hydroxyapatite with electrospun nanofibers of chitosan (or N ‐carboxyethyl chitosan)/poly(vinyl alcohol) (CS or CECS/PVA) is prepared by a mineralization approach in supersaturated CaCl 2 and KH 2 PO 4 solution. It shows a uniform distribution, a good controllability of hydroxyapatite components, and good biocompatibility. It is expected to be used as a bone tissue engineering scaffold. Further details can be found in the article by D. Yang, Y. Jin, Y. Zhou, G. Ma, X. Chen, F. Lu, J. Nie * on page 239.
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