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GZO transparent conductive thin films were deposited by the direct current magnetron sputtering method from a ZnO target doped with Ga2O3 of 3wt% on glass slide substrates under high pressure of argon. The effect of substrate temperature on the GZO film’s morphology, optical and electrical properties is investigated by using scanning electron microscopy (SEM), UV spectrophotometer, four point probe and Spectroscopic Ellipsometer. The results showed that GZO thin films with high quality could be fabricated under the high pressure of argon.When substrate temperature is 250℃ or below, surface morphology of thin films can be significantly improved.With the increase of substrate temperature, the crystal grain become larger, the crystal boundaries narrow and become clear, and reach a best case at 250℃. At the same time, the resistivity of GZO thin films decrease and reach the minimum which is 1.099×10-3 Ω•cm at 300℃ while the average transmittance increase to 90%. Consequently, the properties of morphology began to get worse with the increase of temperature above 300℃.

ABS/PVC blends were prepared over a range of compositions by mixing PVC, SAN, and PB‐g‐SAN. All samples were designed to have a constant rubber level of 12 wt % and the ratio of total‐SAN to PVC in the matrix of the blends varied from 70.5/17.5 to 18/80. Transmission electron microscope and scanning electron microscope have been used to study deformation mechanisms in the ABS/PVC blends. Several different types of microscopic deformation mechanisms, depending on the composition of blends, were observed for the ABS/PVC blends. When the blend is a SAN‐rich system, the main deformation mechanisms were crazing of the matrix. When the blend is a PVC‐rich system, crazing could no longer be detected, while shear yielding of the matrix and cavitation of the rubber particles were the main mechanisms of deformation. When the composition of blend is in the intermediate state, both crazing and shear yielding of matrix were observed. This suggests that there is a transition of deformation mechanism in ABS/PVC blends with the change in composition, which is from crazing to shear deformation. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 687–695, 2006

Polybutadiene‐g‐poly(styrene‐co‐acrylonitrile) (PB‐g‐SAN) impact modifiers with different polybutadiene (PB)/poly(styrene‐co‐acrylonitrile) (SAN) ratios ranging from 20.5/79.5 to 82.7/17.3 were synthesized by seeded emulsion polymerization. Acrylonitrile–butadiene–styrene (ABS) blends with a constant rubber concentration of 15 wt % were prepared by the blending of these PB‐g‐SAN copolymers and SAN resin. The influence of the PB/SAN ratio in the PB‐g‐SAN impact modifier on the mechanical behavior and phase morphology of ABS blends was investigated. The mechanical tests showed that the impact strength and yield strength of the ABS blends had their maximum values as the PB/SAN ratio in the PB‐g‐SAN copolymer increased. A dynamic mechanical analysis of the ABS blends showed that the glass‐transition temperature of the rubbery phase shifted to a lower temperature, the maximum loss peak height of the rubbery phase increased and then decreased, and the storage modulus of the ABS blends increased with an increase in the PB/SAN ratio in the PB‐g‐SAN impact modifier. The morphological results of the ABS blends showed that the dispersion of rubber particle in the matrix and its internal structure were influenced by the PB/SAN ratio in the PB‐g‐SAN impact modifiers. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 2165–2171, 2005

Inclusion complexation kinetics of methyl-β-cyclodextrin (m-β-CD) to hydrophobic molecules confined in an isolated droplet was investigated with optical tweezers. The radius of the droplet shrank over time as m-β-CD was introduced into the sample chamber due to complexation between the hydrophobic molecules and the m-β-CD molecules. The short time behavior of the droplet shrinkage can be described by a model based on Brownian kinetics. The probability of complexation was greater for a branched 2-hexadecanol than for hexadecane. The probability decreased with increasing chain length for short alkanes. The long time behavior of the droplet shrinkage is surprising because the droplets stopped shrinking even when the uncomplexed m-β-CD concentration was still high. We speculate that surface activities of m-β-CD might have slowed the reaction.

The characterization of hydrophobically modified alkali-soluble emulsions (HASE) using conventional techniques such as gel permeation chromatography or static light scattering is difficult because of the hydrophobic association. Two different approaches were taken to prevent the hydrophobic association of HASE polymers in aqueous solution:  (1) hydrolyze the polymer to dislodge the hydrophobic constituents, and (2) use methyl-β-cyclodextrin, which has a hydrophobic cavity and a hydrophilic outer shell, to shield the hydrophobes from associating. Using these two approaches, the molecular weight (Mw), hydrodynamic radius (Rh), and radius of gyration (Rg) of single chains of these polymers were determined using gel permeation chromatography (GPC) and dynamic (DLS) and static (SLS) light scattering techniques. The molecular weight of the control polymer (i.e., polymers with similar composition but with no hydrophobe) is found to be ~7.0 × 10⁵ g/mol. The molecular weights of these polymers with C8, C16, and C20 hydrophobes were found to be ~2.0 × 10⁵ g/mol. By comparing GPC and SLS results, we were able to determine that, except for one chemical site, branching or grafting did not occur in the polymer chain during synthesis.

Powder X-ray diffraction and electrical-resistivity measurement were used to study the structure and the Tcvariation of Y(Ba1−xRx)2Cu3O7−δ(0≤x≤0.2; R=La, Pr, and Nd). The solubility limit was estimated as x=0.05, 0.075, and >0.2 with R=Nd, Pr, and La, respectively, which depends on the ionic radius of dopants. All three series undergo an orthorhombic-to-tetragonal transition at x≈0.15-0.2. Meanwhile, the Tcincreases slightly through a maximum at x≈0.025; then decreases rapidly with x, indicating an overdoped system for YBa2Cu3O7−δ. Whereas, the normal-state resistivity increases with x for all temperature ranges. The similarities and differences with various dopants are discussed in conjunction with ionic size, valence change and hole-filling mechanism.

We have studied the effects of oxygen defects in CuO2planes by 80 keV electron irradiation on YBCO thin films. Similar to the results of Zn-doped YBCO, a significant increase in eesidual resistivity accompaniesTcsuppression, and the relation could be described in the framework of pair-breaking. However, theTcsuppression rate is three times as slow, as predicted byd-wave pairing symmetry. For irradiated samples, (dHc2/dT) nearTcis consistent with the scenario of double pair-breaking, in contrast to the case of Pr-doped YBCO.

Films were deposited on glass substrates by a DC magnetron sputtering method using a ZnO target doped with 2wt% Al2O3. Effects of sputtering on the structural, optical, and electrical properties of ZnO:Al films were investigated. The results showed that film's crystalline quality could be improved along the c-axis direction by increasing the sputtering pressure. Below 12.5Pa, grain size became more refined and the film's surface became more uniform. The resistivity of ZnO:Al films reached a minimum of 1.66×10−3 Ω·cm at 12.5Pa. The films' average transmittances were higher than 80% in the visible (400nm-800nm) region. Furthermore, the bathochromic shift phenomenon of absorption edge had been found in this process. Consequently, the properties of optical, electrical degraded with the increase of pressure above 12.5 Pa.