Vibrational spectra and dissociation of aqueous Na2SiO3 solutions

To facilitate molecular spectroscopic observation of the mysterious transition of dissolved sodium silicate molecules into nanoparticles of desired silica gel and zeolite structures, the IR and Raman spectra of Na₂H₂SiO₄ monomers are studied here in details. It is demonstrated that the 3–0.2 mol/L aqueous solutions of Na₂SiO₃ and Na₂SiO₃ × 9H₂O contain mostly Na₂H₂SiO₄ monomers dissociated about 30%–80%, respectively. In contrast to the common belief the Si–O vibrations of these monomers depend on their dissociation level generating FTIR and Raman bands which are frequently associated with polymer silica structures in the current literature. To stay consistent with the molweight and dissociation measurements, these vibrational assignments are revised in this paper. Some unique and unexpected effects of D₂O used instead of H₂O as solvent are also reported.     

Predictors of high-risk alcohol consumption in young offenders on community orders: Policy and treatment implications.

The present study examined the relationship between a set of individual and contextual variables and high-risk alcohol use among young offenders placed on community orders in New South Wales, Australia. Participants (n = 777) were compared on a set of factors known to be strong predictors of high-risk alcohol use among adolescents. The authors assessed the strength of the relationship between gender, age, ethnicity, geographical region of residence, school attendance, father absence, history of childhood trauma, and the presence of severe conduct disorder on weekly levels of alcohol use. Living in rural locations, not currently attending school, being female, and not having been raised with a biological father present were associated with significantly increased odds of alcohol abuse. Father absence was a more important risk factor for rural young offenders, but school dropout was associated with more hazardous drinking among young offenders in urban areas. Accordingly, the authors suggest family-focused intervention programs for young offenders living in rural areas and school-based programs for vulnerable young people living in urban areas, although programs should consider including both factors for both groups if feasible and warranted. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Minimum cost design of a welded orthogonally stiffened cylindrical shell

In this study the optimal design of a cylindrical orthogonally stiffened shell member of an offshore fixed platform truss, loaded by axial compression and external pressure, is investigated. Ring stiffeners of welded box section and stringers of halved rolled I-section are used. The design variables considered in the optimization are the shell thickness as well as the dimensions and numbers of stiffeners. The design constraints relate to the shell, panel ring and panel stringer buckling, as well as manufacturing limitations. The cost function includes the cost of material, forming of plate elements into cylindrical shape, welding and painting. In the optimization a number of relatively new mathematical optimization methods (leap-frog - LFOPC, Dynamic-Q, ETOPC, and particle swarm - PSO) are used, in order to ensure confidence that the finally computed optimum design is accurately determined, and indeed corresponds to a global minimum. The continuous optimization procedures are adapted to allow for discrete values of the design variables to be used in the final manufacturing of the truss member. A comparison of the computed optimum costs of the stiffened and un-stiffened assemblies, shows that significant cost savings can be achieved by orthogonal stiffening, since the latter allows for considerable reduction of the shell thickness, which results in large material and manufacturing cost savings.     

WATER FLOW AND BINDER MIGRATION DURING DRYING OF COATED PAPER

The aim of this study has been to develop a mathematical model for water flow and binder migration in coated paper. The model can be used for simulation of the stages starting after the coating applicator including infrared and air drying sections. On the basis of the model the moisture, temperature and binder distribution can be determined across the paper thickness. Approximating equations concerning the paper properties are used in the model. We have measured the diffusion coefficient between the water and binder substances. Representative numerical examples are presented for separate and combined infrared and air drying processes.     

Importance of interactions between nutrients and environmental contaminants as a factor in experimental design in toxicological research: with emphasis on selenium and ascorbic acid.

Interactions between dietary components and environmental contaminants may influence the outcome of toxicological testing. A comparison was made between the vitamin and mineral content of laboratory animal basal diets as supplied by two major feed companies. Striking differences in nutrient content of Guinea pig, rat, and primate diets, as supplied by these companies are cited. Attention is drawn to the lack of data on selenium content of these feeds. The importance of Vitamin C in regards to ameliorating toxic effects of heavy metals is discussed.     

Optimal design of a welded I-section frame using four conceptually different optimization algorithms

The purpose of this study is to investigate the suitability of four conceptually different optimization algorithms for specifically the optimal design of welded I-section frames. The cost function to be minimized is the volume of the frame. Constraints on lateral-torsional buckling as well as local buckling of the beam and column webs and flanges are taken into consideration. The algorithms evaluated include a genetic algorithm, a novel leap-frog gradient method without line searches, as well as an orthogonal search method requiring no gradients and the differential evolution technique. Received September 26, 2001 RID="*" ID="*"Part of this paper was presented at the World Congress on Structural and Multidisciplinary Optimization, June 4–8 2001, Dalian, China     

Peter Novak,Mental Symbols: A Defence of the Classical Theory of Mind. Studies in Cognitive Systems 19, Dordrecht,Netherlands: Kluwer Academic Publishers, 1997, xxii + 266 pp., $114.00, ISBN 0-7923-4370-0.

Minds and Machines -     

Automatic Verification of a Behavioural Subset of UML Statechart Diagrams Using the SPIN Model-checker

Statechart Diagrams provide a graphical notation for describing dynamic aspects of system behaviour within the Unified Modelling Language (UML). In this paper we present a translation from a subset of UML Statechart Diagrams - covering essential aspects of both concurrent behaviour, like sequentialisation, parallelism, non-determinism and priority, and state refinement - into PROMELA, the specification language of the SPIN model checker. SPIN is one of the most advanced analysis and verification tools available nowadays. Our translation allows for the automatic verification of UML Statechart Diagrams. The translation is simple, proven correct, and promising in terms of state space representation efficiency. Received September 1999 / Accepted in revised form February 2000     

Genetic testing and psychology: New roles, new responsibilities.

Advances in genetics and genetic testing promise to catalyze a fundamental change in the practice of medicine. Psychologists have much to offer as psychotherapists, researchers, educators, and policymakers to a society heavily influenced by the genetic revolution. To make the most of new opportunities available to mental health professionals in genetics, psychologists must know basic genetic principles and learn what is new about 21st-century genetics. The core competencies for all health professionals developed by the National Coalition for Health Professional Education in Genetics are related in this article to the significant roles psychologists can play in helping individuals with genetic concerns to cope with vulnerability, optimize family interaction, and improve health behaviors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)