Significant Improvement in Activity and Stability of Pt/TiO2 Catalyst for Water Gas Shift Reaction Via Controlling the Amount of Na Addition

Na promoted Pt/TiO₂ catalysts have been studied under high severity, near equilibrium, conditions for use as a single stage WGS catalyst. Addition of 3 wt% Na to a 1 wt% Pt/TiO₂ catalyst has been found to improve water gas shift activity significantly compared to Pt/TiO₂, Pt/CeO₂, and Pt–Re/TiO₂ catalysts. This catalyst is stable when the reaction temperature is higher than 250 °C. Deactivation occurred when the reaction temperature was lower than 250 °C, however, returning the temperature to higher than 250 °C fully recovered activity. TEM observations revealed that addition of Na inhibited Pt particle sintering. These results suggest that Na promoted Pt/TiO₂ is a promising single stage water gas shift catalyst for small scale hydrogen production.     

The scanning micro-sclerometer: a new method for scratch hardness mapping

A new surface engineering research tool, called a scanning microsclerometer (SMS), has been developed. It uses nano-indentation technology and a piezoelectric transducer positioning system to generate high-precision scratch patterns on the surfaces of metals and, by monitoring the instantaneous displacement of the stylus tip, can generate scratch hardness and scratching force maps of the surface. A dual-stroke process is used. The first stroke at low load profiles the surface to establish a reference datum and the second pass, in the opposite direction and at higher load, produces the indentation scratch. Examples of micro-scratch hardness mapping experiments, using scratch spacings of 1·0 μm, on a silicon carbide-based ceramic composite are used to illustrate the capabilities of the SIVIS. Using end-on fibers in the rectangular stylus scanning area, the difference in scratch hardnesses of the fibers, the matrix, and even the thin carbon coatings in the fiber-matrix interface could be detected. The SMS was originally developed to produce scratch hardness maps, but it is also useful for conducting accurately controlled, single-point micro-machining patterns and in studies of differential material abrasion.     

Acceptance and values-based action in chronic pain: A study of treatment effectiveness and process.

Developing approaches within cognitive behavioral therapy are increasingly process-oriented and based on a functional and contextual framework that differs from the focus of earlier work. The present study investigated the effectiveness of acceptance and commitment therapy (S. C. Hayes, K. Strosahl, & K. G. Wilson, 1999) in the treatment of chronic pain and also examined 2 processes from this model, acceptance and values-based action. Participants included 171 completers of an interdisciplinary treatment program, 66.7% of whom completed a 3-month follow-up assessment as well. Results indicated significant improvements for pain, depression, pain-related anxiety, disability, medical visits, work status, and physical performance. Effect size statistics were uniformly medium or larger. According to reliable change analyses, 75.4% of patients demonstrated improvement in at least one key domain. Both acceptance of pain and values-based action improved, and increases in these processes were associated with improvements in the primary outcome domains. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A Comparison of Measures for Detecting Natural Shapes in Cluttered Backgrounds

We propose a new measure of perceptual saliency and quantitatively compare its ability to detect natural shapes in cluttered backgrounds to five previously proposed measures. As defined in the new measure, the saliency of an edge is the fraction of closed random walks which contain that edge. The transition-probability matrix defining the random walk between edges is based on a distribution of natural shapes modeled by a stochastic motion. Each of the saliency measures in our comparison is a function of a set of affinity values assigned to pairs of edges. Although the authors of each measure define the affinity between a pair of edges somewhat differently, all incorporate the Gestalt principles of good-continuation and proximity in some form. In order to make the comparison meaningful, we use a single definition of affinity and focus instead on the performance of the different functions for combining affinity values. The primary performance criterion is accuracy. We compute false-positive rates in classifying edges as signal or noise for a large set of test figures. In almost every case, the new measure significantly outperforms previous measures.     

Effects of Interface Roughness on Residual Stresses in Thermal Barrier Coatings

Using a newly developed object-oriented finite-element analysis method, both an actual microstructure and model microstructures of a plasma-sprayed thermal barrier coating system were numerically simulated to analyze the full-field residual stresses of this coating system. Residual stresses in the actual microstructure were influenced by both the irregular top-coat/bond-coat interface and cracks in the top coat. By treating the microcracked top coat as a more-compliant solid microstructure, the effects of the irregular interface on residual stresses were examined. These results then could be compared to results that have been obtained by analyzing a model microstructure with a sinusoidal interface, which has been considered by some earlier investigators.     

Do Source of Income Anti-discrimination Laws Facilitate Access to Less Disadvantaged Neighborhoods?

Vouchers have come to be seen as a tool for promoting economic and racial/ethnic integration. Discrimination based on Source of Income (SOI), however, could hinder the use of vouchers to move to more desirable neighborhoods. State and local SOI anti-discrimination laws (SOI laws) are one policy response to address this issue. SOI laws make it illegal for landlords to discriminate against voucher recipients solely on the basis of their having a voucher. The research presented here tested whether SOI laws in the USA improve locational outcomes for voucher recipients. This research found that the impacts of SOI laws on locational outcomes are mixed. We found substantively important reductions in neighborhood poverty rates associated with the implementation of SOI laws and small but statistically significant reductions in minority concentration as well. The concentration of voucher recipients in a neighborhood, however, does not appear to be related to SOI law implementation.     

Stereological estimation of the total volume of MR visible brain lesions in patients with multiple sclerosis

Point counting represents a convenient and efficient technique for estimating the area of transects through multiple sclerosis (MS) lesions on magnetic resonance (MR) images obtained for sections through the brain. When sectioning has been performed according to the Cavalieri method, unbiased estimates of the total volume of MR-visible MS plaques can be obtained with a precision of 3–5% in 5–10 min.     

Revised Estimates of Dimension and Exercise Variance Components in Assessment Center Postexercise Dimension Ratings.

The authors reanalyzed assessment center (AC) multitrait-multimethod (MTMM) matrices containing correlations among postexercise dimension ratings (PEDRs) reported by F. Lievens and J. M. Conway (2001). Unlike F. Lievens and J. M. Conway, who used a correlated dimension-correlated uniqueness model, we used a different set of confirmatory-factor-analysis-based models (1-dimension-correlated Exercise and 1-dimension-correlated uniqueness models) to estimate dimension and exercise variance components in AC PEDRs. Results of reanalyses suggest that, consistent with previous narrative reviews, exercise variance components dominate over dimension variance components after all. Implications for AC construct validity and possible redirections of research on the validity of ACs are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Overt and Relational Aggression and Perceived Popularity: Developmental Differences in Concurrent and Prospective Relations.

Relations of overt and relational aggression with perceived popularity among children and early adolescents were examined in 2 studies (Ns = 607 and 1,049). Among older youths, positive concurrent relations found between overt aggression and perceived popularity became nonsignificant when relational aggression was controlled, whereas positive associations found between relational aggression and perceived popularity held when overt aggression was controlled. Aggression and perceived popularity were not positively related for the younger participants. The 2nd study also examined the temporal ordering of these relations over 6 months. For older girls, positive relations between relational aggression and perceived popularity were bidirectional. For older boys, relational aggression did not predict increased perceived popularity, but perceived popularity predicted increased relational aggression. Implications for intervention are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)