Gallium (III) Triflate Catalyzed Beckmann Rearrangement

Gallium triflate catalyzed Beckmann rearrangement is described. Various aliphatic or aromatic amides are obtained from the corresponding ketoximes in good yields. Gallium triflate exhibits high catalytic activity for a wide variety of substrates.     

An improved method for high-curvature detection with applications to automated inspection

Digital curve acquisition with a vision system introduces a large amount of degradation. At the same time ‘corners’ convey important visual information. Unfortunately they are found in the same spectral domain as the quantization noise. Low-pass filtering of the curvature function is compared with more sophisticated methods that keep the angles ‘sharp’. An automated inspection is successfully performed, demonstrating the efficiency of a new method.     

The tightness of retail packaging: A selection of test methods to be used for a wide range of packed products

The tightness of retail packagings and of their closures is of primary importance both for domestic and industrial products. For this reason, a research programme designed to establish proper testing methods for a wide range of ‘packaging + product’ combinations, in order to check their tightness or permeability, was set up. All the available testing methods were reviewed, the most reliable ones selected and their sensitivity determined. More than 200 combinations of ‘packaging + product’ belonging to five families of consumer products were examined and their tightness/permeability problems noted. Finally, specific testing methods were assigned to each combination of ‘packaging + product’. All these examples are currently in use in the packaging laboratory as a guideline for the testing of every kind of packaging.     

Reliability Criteria when Standardizing High Contact Density Connectors

The following paper presents the results of a comparative reliability study conducted on three tpes of high density circular connectors, conforming to NAS 1599, MIL. C. 38 999, and MIL. C. 81 511. After runing numerous relability tests, Souriau has been able to develop a highly successful high density connector.     

Assessment of the method for calculating the Lewis number of H2/CO/CH4 mixtures and comparison with experimental results

This paper investigates the various techniques used in the literature to calculate the effective Lewis number of two-component (H₂/CO and H₂/CH₄) and three-component fuels (H₂/CO/CH₄ and H₂/CO/CO₂) over a wide range of equivalence ratios (0.6 ≤ φ ≤ 1.4) under laminar flame conditions. The most appropriate effective Lewis number formulation is identified through comparison with experimentally extracted Lewis numbers (Le). The paper first identifies the proper methodology to extract the experimental Le from the burned Markstein length of an outwardly propagating flame. Second, the different methodologies for the calculation of the effective Le are presented and compared to experimental results for H₂/CH₄ and H₂/CO mixtures. Based on the experimental results, it is shown that the calculation of the effective Le of mixtures can be divided into a three-step procedure depending on the equivalence ratio: (1) calculation of the Le for each fuel and the oxidizer; (2) use of the Le mixing rule; and (3) assessment of the necessity or not of combining the fuel's and oxidizer's Lewis numbers. The paper shows that, in rich mixtures, the oxidizer Le needs to be taken into account. Lastly, the methodology is validated for H₂/CO/CH₄ and H₂/CO/CO₂ fuels.     

Training system issues in the year 2000.

This article discusses the influence of future changes in the demographics of working populations and the characteristics of the workplace on research, development, and policy for training systems. Analyses of these changes indicate that there will be more expectations that training programs will serve as a positive hope to maximize the potential of each person. This will result in increased emphasis on research to identify abilities required to perform more cognitively complex jobs. Also, research on basic skill and support programs to permit unskilled youth to enter the world of work will be required. In addition, there will be a need for research on training necessary to help future managers and leaders work with members of a more diverse work force. Finally, the implications of these changes suggest that we need policies that consider research and development on retraining as a national need to help all individuals maximize their individual talents. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Composites realized by hand lay-up process in a civil engineering environment: initial properties and durability

The repair, the reinforcement as well as the setting in safety of buildings and existing reinforced and/or pre-stressed concrete structure is a real technological stake and a socio-economic problem for the near future. The introduction of composites in civil engineering is an interesting answer to these goals, but they brought an important amount of new problems that have to be solved for safe structural applications under combined mechanical and environmental loadings. In fact during the past five years, we have witnessed exponential growth in research or field demonstrations of fiber-reinforced composites in civil engineering. Manufacturers and designers have now access to a wide range of composite materials. However, they face great problems with forecasting the reliability of composite materials. Their introduction in civil engineering applications is a difficult operation due to working environment and weathering conditions. The objective of this paper is to study the effect of these conditions and their consequences on the mechanical properties of the final composite. An analysis of the rheological (viscoelastic) properties was carried out in order to observe the glass transition temperature evolution according to reactive mixture stoichiometry and weathering conditions.     

The modified quasi-chemical model: Part II. Multicomponent solutions

Further improvements to the modified quasi-chemical model in the pair approximation for shortrange ordering (SRO) in liquids are extended to multicomponent solutions. The energy of pair formation may be expanded in terms of the pair fractions or in terms of the component fractions, and coordination numbers are permitted to vary with composition. The model permits complete freedom of choice to treat any ternary subsystem with a symmetric or an asymmetric model. An improved general functional form for “ternary terms” in the excess Gibbs energy expression is proposed. These terms are related to the effect of a third component upon the binary pair interaction energies. It is shown how binary subsystems that have been optimized with the quasi-chemical model can be combined in the same multicomponent Gibbs energy equation with binary subsystems that have been optimized with a random-mixing Bragg-Williams model and a polynomial expression for the excess Gibbs energy. This is of much practical importance in the development of large databases for multicomponent solutions. The model also applies to SRO in solid solutions as a special case, when the number of lattice sites and coordination numbers are constant.     

The modified quasi-chemical model: Part III. Two sublattices

The modified quasi-chemical model in the pair approximation for short-range ordering (SRO) in liquids is extended to solutions with two sublattices. Short-range ordering of nearest-neighbor pairs is treated, and the effect of second-nearest-neighbor (SNN) interactions upon this ordering is taken into account. The model also applies to solid solutions, if the number of lattice sites and coordination numbers are held constant. It may be combined with the compound-energy formalism to treat a wide variety of solution types. A significant computational simplification is achieved by formally treating the nearest-neighbor pairs as the “components” of the solution. The model is applied to an evaluation/optimization of the phase diagram of the Li,Na,K/F,Cl,SO₄ system.