Activation of timber surfaces by flame and corona treatments to improve adhesion

Long-term durability of a structural adhesive joint is an important requirement, because it has to be able to support the required design loads, under service conditions, for the planed lifetime of the structure. One way of improving bond durability is through the use of surface treatments prior to bonding, which will activate the adherends’ surface, making it more receptive to the adhesive. In this study, the effects of two surface pre-treatments (corona discharge and flame ionization) on three timbers (maritime pine, iroko, and European oak) were evaluated quantitatively through contact angle measurements. These measurements allowed the determination of the changes in the timber surface thermodynamic characteristics, thus indicating which pre-treatment performed better. The results showed that both techniques increased each timber's surface free energy, which could translate into a durability enhancement of bonded joints. Overall, the corona-discharge treatment looks more promising, since this treatment leads to a bigger increase in the timber's surface energy, especially in its polar component, whilst also tended to be less species specific, less susceptible to variation, and the treatment effects lasted longer for this type of treatment.     

Modeling the energy potential of biomass – H2RES

Modeling biomass as a renewable energy source poses many challenges with respect to feedstock variability, which are difficult to account for. It is found that at the preliminary stages of energy planning, heating value and moisture content of the feedstock are the most important factors. In addition, the effects of harvesting, transportation and storage are found to be significant even though they are often overlooked. Using the gathered information a biomass module for energy planning is created and integrated to H₂RES, a renewable energy planning program. Using this excel based software, a case study for a wood processing factory is performed, using the waste wood as feedstock. Comparing various scenarios, it is concluded that using a combination of solid oxide fuel cells, solar panels and steam turbines can satisfy the factories energy requirements with excess sold to the grid.     

Application of high-throughput computing in bioinformatics

We describe the challenges faced when developing a Linux/PC-based cluster to apply bioinformatics algorithms to the rapidly increasing raw genomics data available. The calculations, which take around two months to complete, result in a powerful resource that can be used for data mining--most obviously for the human genome. Our current infrastructure consists of a 1314 node cluster with 1734 processors supporting both production and research. This paper highlights the problems in achieving high data throughput with such systems and shows that raw computer power is only one component of a complex problem.     

Uterine activity patterns in uterine rupture: a case-control study

The effects of methylprednisolone therapy on the susceptibility of dystrophin-deficient myofibers to contraction-induced injury were evaluated in the mdx mouse diaphragm model of Duchenne dystrophy. Mdx myofibers were abnormally vulnerable to injury induced by high-stress eccentric contractions. However, methylprednisolone therapy did not significantly alter the degree of contraction-induced injury. These data suggest that beneficial effects of corticosteroid therapy in Duchenne dystrophy are unlikely to be related to a change in the threshold for contraction-induced myofiber damage.     

Salmonella carriage in an Irish pig herd: correlation between serological and bacteriological detection methods

Salmonella carriage in pigs represents a serious health problem that undoubtedly contributes to the spread of human disease. Thus, the efficient and reliable testing of farm animals for bacteria such as Salmonella is an important aspect of any efficient control strategy. Serological analysis of 15 meat juice samples detected antibodies against Salmonella in some. but not all, of the animals identified bacteriologically as harboring the pathogen, indicating a lack of correlation between the bacteriological and serological methods used for Salmonella detection. The results suggest that testing by enzyme-linked immunosorbent assay is appropriate at the herd level, with culture methods preferable for individual animal analysis. A novel culture protocol detected Salmonella in the cecal contents of 15 pigs, whereas a method based on the European Standard identified only 9 pigs as being Salmonella-positive. During the study, an unusual finding was the relatively high incidence of Salmonella London carriage in the pigs tested.     

Effect of environmental hydrogen pressure on the hydrogen yield from x-irradiated polyethylenes

An experimental assembly incorporating a capacitance-type, differential pressure transducer, which provides resolutions of 3 × 10^?4 torr at pressures extending to 30 torr, has been employed to monitor the effect of hydrogen environmental pressure on the hydrogen yield from x-irradiated polyethylenes. Contrary to the observations of previous investigators, the hydrogen yield is found to be independent of hydrogen environmental pressures extending over the critical range up to at least 30 torr. It is demonstrated that neglecting the temperature and density gradients inherent in closed-volume irradiation assemblies employing cryogenic traps to separate liberated gases into condensable and noncondensable fractions may lead to erroneous conclusions with respect to gas yields arising from the irradiation of materials. A homogeneous, variable-plate separation ion chamber consisting of a polyethylene body and utilizing flowing ethylene as the cavity gas was employed to obtain total volatile G values of 3.6 ± 0.4, 3.8 ± 0.4, and 4.0 ± 0.4 molecules/100 e.v., for Marlex 6002, Dow Ziegler (Q 917.5), and DuPont A-1410 polyethylenes, respectively. A hydrogen contribution of approximately 98 mole-% was obtained with this experimental method.