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A two-stage system for octachlorinated dibenzo-p-dioxin (OCDD)-contaminated soil remediation was developed. Soil washing using emulsified oil (EO) was applied in the first stage for OCDD extraction followed by the second stage of bioremediation using P. mendocina NSYSU for remaining OCDD biodegradation. The major tasks included (1) determination of optimal soil washing conditions for OCDD extraction by EO, (2) evaluation of feasibility of OCDD biodegradation by P. mendocina NSYSU under aerobic cometabolic conditions using EO as the primary substrate, and (3) assessment of the effectiveness of OCDD removal using the two-stage system. During the soil washing stage, EO with two different oil-to-water ratios (1:50 and 1:200) and pore volumes were tested with initial soil OCDD concentration of 21,000 µg/kg. Results indicate that EO could effectively improve the solubility and desorption of OCDD in soils. Up to 74% of OCDD removal could be obtained after washing with 60 PVs of EO and dilution factor of 50. After the soil washing process, enriched P. mendocina NSYSU solution was added into the reactor to enhance the aerobic biodegradation of remaining OCDD in soils. P. mendocina NSYSU could use adsorbed EO globules as substrates and caused significant OCDD degradation via the aerobic cometabolic mechanism. Approximately 82% of the remaining OCDD could be removed after 50 days of operation, and P. mendocina NSYSU played important roles in OCDD biodegradation. Up to 87% of OCDD was removed through the EO washing and biodegradation process. The two-stage system is a potential technology to remediate dioxin-contaminated soils.

The individuals of tertiary amines, including imidazole (1-amine), 1,2-dimethylimidazole (2-amine), 2,4,6-tris(dimethylamino-methyl)phenol (3-amine), 1-methylimidazole (4-amine), and 2-methylimidazole (5-amine), were added into UV-curable epoxide resins, respectively, and the effects on UV/thermal conversions, thermal properties and adhesion strengths for various types of substrates were investigated. According to the experimental results, the extent of effects of amines on physical properties was found in the order of: 3-amine > 4-amine > 1-amine > 2-amine > 5-amine. The resin with 3-amine exhibited the highest glass transition temperature ( T g = 72.3 °C) value and the lowest coefficient of thermal expansion (CTE = 70.8 ppm/°C), which also exhibited the highest adhesion strengths on various substrates, on glass (greater than 199 kg/cm 2 ), ITO (greater than 182 kg/cm 2 ), PET (115 kg/cm 2 ), and stainless steel (232 kg/cm 2 ), and possesses great potentials for advanced opto-electronic applications.

Preparation of UV-curable intercalated/exfoliated epoxide/acrylateclays nanocomposite resins with the addition of specific monomers and solvent via the consideration of solubility parameter and chemical reactivity was carried out in this work. Due to the good compatibility with surfactant in acrylateclays and the cationic oligomer in resin matrix, the two additive monomers dispersed uniformly in resin matrix with the swollen acrylateclays before UV curing. As revealed by conversion ratio and DTG analyses, chemical bonds between the two additive monomers, the cationic oligomers and surfactant in acrylateclays were formed during UV irradiation. This, in turn, generated a hybrid acrylate-based/epoxy network and effectively enlarged the lamellae spacing of inorganic clays in nanocomposite resins prepared in this work. The XRD and TEM characterizations revealed that the intercalated clay domains containing exfoliated lamellae about 1 nm in thickness uniformly disperse in polymeric matrix. The nanocomposite resin containing 5 wt.% inorganic filler possessed the physical properties as follows: T d-5% = 213 °C, CTE = 80.5 ppm/°C, moisture absorption = 6.12%, average optical transmittance = 83.17%, and adhesion strength on glass substrate = 43.8 kgf/cm2. The analyses above indicated that the formation of polymeric interpenetrating networks and nanometer-scale exfoliation of clay lamellae not only improve the thermal properties and resistance to moisture permeation, but also retain highly optical transmittance and satisfactory adhesion strength of nanocomposite resins prepared in this work. A better device lifetime property was hence achieved when the nanocomposite resins were applied to the packaging of OLEDs.

The work reported demonstrates that the yellowness of UV-curable epoxide resins can be improved by adding certain tertiary amines in appropriately determined amounts. According to the results of our experiments, 2.0 wt% benzoyl peroxide added to a resin effectively enhances the crosslinking density, and phenolic free radicals are produced during UV curing, which consequently induce yellowness via the reaction of oxygen and the free radicals. Imidazole (1-amine) and tertiary amines, including 1,2-dimethylimidazole (2-amine), 2,4,6- tris(dimethylaminomethyl)phenol (3-amine), 1-methylimidazole (4-amine) and 2-methylimidazole (5-amine), were chosen to be added to resins, and their effects on UV conversion and yellowness were investigated. According to the experimental results, tertiary amines in the resin can provide a certain degree of improvement in yellowness index (� YI) and color parameter (� E ∗ ab) of the resin sample. Whatever the type of tertiary amine, it is found that the optimum content of amine in resin is 1.0 wt%. Also, among the studied amines, the 3-amine exhibits the highest UV reactivity and the best efficiency for yellowness improvement with values ofa ∗ , � b ∗ , � YI andE ∗ ab as low as −1.4, 6.23, 11.27 and 6.48, respectively.  2007 Society of Chemical Industry

This work studies the effects of the monomer types, the number of hydroxyl functional groups (–OH) on polyol monomers, and the equivalent weight ratio of dicycloaliphatic epoxide to polyol for cationic polymerization (the R value) on the adhesion strength of UV-curable epoxy resins applied to organic light-emitting device (OLED) packaging. It was found that the volume shrinkage of resins after UV curing is related to the crosslinking density of the resin. The smallest volume shrinkage implied the highest adhesion strength of resin on glass substrate since the internal stress was minimized. This study observed that the resin containing polyol monomer is able to achieve the smallest degree of shrinkage (1.72%) and the highest adhesion strength (153.35 kg/cm 2 ) on glass substrate.

Preparation and property characterization of encapsulation resin contained hexagonal boron nitride (hBN) as inorganic filler were carried out in this work. The dielectric properties, coefficient of thermal expansion (CTE), thermal conductivity, curing kinetics, adhesion strength and viscosity of the resins with the load of hBN filler ranging from 9.2 to 25.7 vol.% (20–70 wt.%) were evaluated. It was found that the dielectric properties of resin containing SiO2 filler are inferior to that containing hBN. Also, the resins possessed lower CTE and the higher T g when the hBN contents were high (>15 vol.%) and the resin containing 25.7 vol.% hBN exhibited the largest thermal conductivity of 1.08 W/m K. Adhesion strength of the composite resins decreased with increase of hBN content and the adhesion strength on various substrates was found to be in the order of: alumina > Si wafer > eutectic PbSn solder.

In this study we investigated five different types of organo-functional silanes containing vinyl, epoxy, amino, methacrylic and acrylic groups in the cationic polymerization of epoxide resin and studied their effects on epoxide adhesion strength to indium tin oxide (ITO) substrate via a pull test. The adhesion strength of epoxide resins was found to be in the order vinyl > methacrylic > acrylic > epoxy > amino. The silane containing vinyl group enhanced the adhesion strength, since it was able to promote free-radical polymerization. As to the silane containing amino group, it retarded the photo-polymerization of cationic photoinitiator in the resin and thus the lowest adhesion strength was observed. It was found that the resin sample containing 1 wt% of vinyl group silane possessed the highest adhesion strength of 91.42 kg/cm2 to ITO glass. An excessive amount of silane added in the resin generated too much H2O that diluted the concentration of resin and deteriorated the adhesion strength.

The phase space for a heterogeneous system containing a grain boundary involves a relatively large number of variables (i.e., at least six plus the number of components), and it is therefore conceptually possible to induce a large variety of grain boundary phase transitions by selectively varying these parameters. Despite this, a review of the literature reveals that there have been virtually no clear-cut experimental observations of transitions reported in which the boundary structure has been observed as a function of time under well defined conditions. In current work, we are searching for roughening/faceting transitions and melting transitions for boundaries in Al by hot stage transmission electron microscopy. A clear example of a reversible roughening/faceting transition has been found. No evidence for melting has been found for temperatures as high as 0.96 T/sub m/ (by monitoring GBD core delocalization in several special boundaries with ..sigma.. less than or equal to 13) or 0.999 T/sub m/ (by observing the local diffraction contrast at general boundaries in polycrystalline specimens).