Conductivity of crosslinked low surface energy epoxy coatings

A new and straightforward method has been studied to prepare crosslinked low surface energy semiconductive epoxy coatings. The low surface energy is obtained by adding a small amount of partially fluorinated bifunctional primary amine Jeffamine D230 crosslinker and the conductivity is achieved by adding a small amount of semiconductive nanosized Cobalt(III) phthalocyanine particles. The use of partially fluorinated crosslinker strongly influences the conductivity, the conductive particle network structure, and the network distribution in the coatings. Compared to coatings that are free of fluorine, variations in fractal dimension, percolation threshold, particle‐containing layer thickness, and conductivity level are observed as the amount of fluorinated species is varied. These differences can be explained by (local) differences in effective Hamaker constant, viscosity, curing rate, evaporation of the solvent, and presence or absence of polymer matrix between the particles in the network. Our results suggest that other crosslinked semiconductive low surface energy epoxy coatings can be realized in a similar manner, but careful optimization of processing conditions is required to obtain the desired conductivity levels at low filler concentration. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Chem 47: 366–380, 2009     

Novel four-hydrogen-bond assembled oligoamide dimer with pyrazoline moieties and its photoluminescent properties

In this paper,the synthesis and characterization of a triarylpyrazoline modified four-H-bonded molecular duplex are described. Its molecular structure has been confirmed by ~1H NMR and ESI-MS.The duplex emits strong pure blue light peaking at 448 and 452 nm under UV photoexcitation in solution and solid state,respectively,and its relative photoluminescence quantum efficiency in solution is determined as 0.778 using quinine sulfate as reference.In concentration of>40 mmol/L,the duplex can gelate DMSO, and...     

Effect of preparation methods on Pt/alumina catalysts for the hydrogen iodide catalytic decomposition

Three kinds of Pt/alumina catalysts were prepared by impregnation-hydrogen reduction,impregnation-hydrazine reduction and electroless plating methods.Their differences in the structures,specific areas and particle sizes were characterized by XRD,BET and TEM,respectively.Furthermore,their catalytic activities for the hydrogen iodide(HI)decomposition were evaluated in a fixed bed reactor.The results show that the catalyst 5%Pt/Al_2O_3 prepared by the electroless plating has the optimum catalytic properties...     

Generation of Multi-ion Graph States with Trapped Ions in Thermal Motion

We propose a scheme for generating multi-ion graph states using many trapped ions in thermal motion. Our generation scheme is insensitive to external state since the interaction between ions and laser fields does not involve the external degree of freedom. The scheme can be well realized within the current experimental technique.     

Quantum Superdense Coding Based on Coherent States in Cavity QED

A physical scheme for the implementation of quantum superdense coding has been proposed in Cavity QED. The detuned interaction between Λ-type three-level atoms and coherent fields constitute the main superdense coding process. The quantum superdense coding can be realized in an easier way, and the atoms are not excited during the whole process, so the effect of atomic decay is eliminated naturally.     

Numerical simulations on the formation of laser speckles with nanofluids

Our recent work revealed that speckles can be formed when nanofluids containing a proper volume fraction of nanoparticles are illuminated by a monochromatic laser beam [Qian M, Liu J, Yan M-S, Shen Z-H, Lu J, Ni XW, et al. Investigation on utilizing laser speckle velocimetry to measure the velocities of nanoparticles in nanofluids. Opt Express 2006; 14: 7559–66]. In this paper, two different physical models are established to figure out the speckle-formation mechanism. The photon–nanoparticle-collision model emphasizes the random collisions between photons and nanoparticles, and Monte Carlo method is used to simulate how the incident photons move in the vessel containing nanofluids. However, in the electric-dipole model, each illuminated nanoparticle becomes an electric dipole and sends out scattering lights, and the coherent addition of the scattering lights from nanoparticles is numerically calculated. Finally, from the numerical results, the speckle-formation mechanism is figured out.     

SUPER TOUGH GELS WITH A DOUBLE NETWORK STRUCTURE

Living tissues work with fantastic functions in soft and wet gel-like state.Thus,hydrogels have attracted much attention as excellent soft and wet materials,suitable tot making artificial organs for medical treatments.However, conventional hydrogels are mechanically too weak for practical uses.We have created double network (DN) hydrogels with extremely high mechanical strength in order to overcome this problem.DN gels are interpenetrating network (IPN) hydrogels consisting of rigid polyelectrolyte and s...     

数域Q(P_1~(1/2),…,P_t~(1/2))(t≥4)的类数为偶数

设t≥4，ｐ１，…，ｐｔ为不同的模４余１的素数，本文证明了数域P1~(1/2)，…，Pt~(1/2)的类数为偶数．