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A new approach that takes advantage of both soft-modeling and pattern recognition methods is proposed to analyze kinetic data monitored spectrometrically to classify structurally similar nitroaniline isomers. The colorimetric condensation reaction of 1,2-naphthoquinone-4-sulfonate (NQS) with amines has been used to classify 2-, 3-, and 4-nitroaniline on the basis of their different kinetic properties. These nitroanilines react differentially with NQS at pH 7 to produce a colored product. Soft-modeling approaches such as multivariate curve resolution–alternating least squares (MCR–ALS) and simple-to-use interactive self-modeling mixture analysis (SIMPLISMA) followed by multiplicative signal correction have been used as preprocessing procedures to obtain patterns diagnostic for the analytes. Rank analysis was initially performed using determination of rank by augmentation to detect any species present during the course of the reaction in the system under investigation. The spectra and kinetic profiles of all absorbing species present in the raw measurements were obtained from SIMPLISMA and MCR–ALS resolution. The kinetic profiles were then used as input of the pattern recognition algorithm. The response patterns were systematically classified using linear discriminant analysis with high classification accuracy. Either all or one of the resolved profiles related to the components involved in the reaction can be used for identification of nitroaniline isomers. Copyright © 2013 John Wiley & Sons, Ltd.

SUMMARY At present, corrugated plates have numerous applications such as web of plate girders and aerospace applications. Higher out-of-plane stiffness and initial elastic strength of the corrugated plates compared with flat plates are reasons for consideration. This study investigates the behavior of trapezoidally corrugated steel plate shear walls (TCSPSWs) under monotonic and cyclic loadings. Finite element analyses that include both material and geometric nonlinearities are employed for the examination. The results from finite element analysis are verified through tested specimen findings. Moreover, the behavior of the steel shear walls with the flat infill panels and the corrugated plate infill panels is compared. The results show that explicit dynamic analysis is the most suitable analysis for the TCSPSWs under quasi-static loading. Furthermore, although strength of the TCSPSWs obtained from the finite element analysis and the test are fully coincident in elastic region, nonetheless, they are fairly coincident in elastic–plastic and plastic region. Copyright © 2012 John Wiley & Sons, Ltd.

Summary Studies on corrugated steel shear walls (CSSWs) generally indicate noticeable increase of energy absorption, as well as increasing shear buckling capacity of corrugated plates being more likely rather than the flat plates. In this paper, the effect of variation in the angle of trapezoidal plate on the behavior of CSSWs has extensively been investigated. Three specimens of CSSW with 1 story and single bay in half scale are tested under cyclic load. The observations of experiment do indicate that stress concentration has been increased in the corner of subpanels, by increasing of the corrugation angle. Development of the tensile field and wall yield and damage depends on the geometry of the plate. By increasing the corrugation angle, the stiffness and energy dissipation decrease; in addition, large loss of strength takes place. Comparing the numerical and experimental results indicates that for a closer look at behavior of trapezoidal CSSWs, fracture mechanics, fatigue, and damping of materials should be considered by numerical analysis.

Summary Different ways have been presented to prevent elastic buckling of steel shear walls. One of these solutions is corrugated shear wall. In this type of wall, shear buckling strength increases without increasing the thickness of the panel. Numerical modeling results indicate that, always, shear buckling strength of corrugated panels is more than the flat panels and with the right choice of the geometric parameters of corrugated panels; without increasing the thickness of the panel, we can improve buckling strength significantly. In the trapezoidal corrugated panels, reducing the width of the subpanels do not always increase buckling strength of the panel, but it changes the panel buckling shape from the local buckling mode to the global buckling. In addition, in panels, with the low width of the subpanels, elastic buckling does not happen in the subpanels. Comparing numerical analysis with the theoretical relations showed that the results of numerical analysis with the relations that include local buckling, global buckling, and shear yielding stress, have a better approximation and in another word, interaction buckling is the combination of the local buckling, global buckling, and shear yielding stress.

Bipyridinium tribromide reacts with thiols in the presence of thionyl chloride to yield symmetric trisulfide derivatives (RSS(O)SR) as the major products. Two possible mechanisms are advanced to explain the chemistry.