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SYNOPSISProton Nuclear Magnetic Resonance (NMR) spectroscopy was used to study the adsorption of a hexadecyl-terminated poly(oxyethy1ene) surfactant (nominal molecular weight of 1120 g/mol) onto hydrophobic polystyrene latex particles. The adsorption process affects the NMR response of the surfactant; various surfactant populations are represented by different features in the NMR spectra. An analytical method that utilizes surfactant systems with and without polystyrene latex particles was employed to determine the capability of NMR to observe adsorbed surfactant close to the particle surface. At the initial stages of surfactant adsorption, the oxyethylene chain interacts with the particle surface in a pancake-like conformation. At higher surfactant concentrations, surfactant molecules are bound to the particle surface and also exist as micelles or are free in solution; approximately one-third of the bound, 20-unit oxyethylene chains are near the surface and are not detected by NMR. Using a theoretical monomer density profile, laser light-scattering measurements, and the NMR results, an effective NMR detection limit of 1 nm from the particle surface has been calculated. 0

Drawing on second language (L2) motivation constructs modelled on Dörnyei's (2009) L2 Motivational Self System, this study explores the relationship between language testing experience and the motivation to learn English among young adolescents (aged 12-15) in South Korea. A 40-item questionnaire was administered to middle-school students (N = 341) enrolled in a private language school (hakwan). Exploratory factor analysis (EFA) identified five salient L2 motivation factors. These factors were compared to four learner-background characteristics: gender, grade level, L2 test-preparation time, and experience taking a high-stakes university-level language test. The results suggest that second language motivation, based on the L2 motivation factors identified as most salient in this educational context, was significantly associated with the amount of time spent preparing for language tests and experience taking a high-stakes language test intended primarily for university-entrance purposes. Young South Korean adolescent learners' testing experiences and their motivation to learn English are discussed in relation to the social consequences of test use and ethical assessment practices.

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