Poly(acrylic acid) (PAA) and cetyltrimethylammonium bromide (C16TAB) are found to interact strongly in aqueous solution. The properties of the system are determined mainly by the parameter β, defined as [C16TAB]/[PAA]; the PAA concentration is expressed as monomers. Light scattering measurements in dilute solutions show that a single PAA chain binds several C16TAB micelles to form a complex. At β ≈ 1 (independent of the PAA concentration), the complex is saturated with surfactant. At higher β, free micelles coexist with the complexes. The hydrodynamic radius of the complex is smaller than (β < 1) or similar to (β > 1) the radius of the surfactant-free PAA coil. Estimates of the hydrodynamic virial coefficient show that the effective repulsion between complexes increases with β up to β ≈ 1 where a dramatic change is brought about by the screening effect of free micelles. Time-resolved fluorescence quenching shows that the aggregation number of the micelles in the complex increases from 50 at β = 0.35 to 90 at β = 1. (The aggregation number for 20 mM C16TAB in the absence of polymer is estimated as 107.) Pyrene lifetime measurements indicate that this change is accompanied by an increase of the apparent degree of bromide ion binding to the micelles from 50% to 95% of the value for free C16TAB micelles. Furthermore, the decreasing influence of the polymer on the surfactant assembly with increasing β is supported by the variation of the intramicellar quenching rate constant. Viscosity measurements confirm that no multipolymer complexes form in the studied concentration range. pH measurements show that the degree of dissociation of the polymer acidic groups increases when the polymer binds to the micelles.

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This article investigates the situation of Swedish upper secondary school students who have been subject to distance education during the COVID-19 pandemic crisis. We understand the transition from onsite education to distance education as a recontextualization of pedagogical practice, our framing follows loosely concepts from Bernstein. Given that the field of upper secondary education is highly socially structured it is relevant to enquire into the social dimensions of distance education. For this purpose, we have analysed answers to an open-ended question in a survey answered by 3,726 students, and related them to a cluster analysis distinguishing three main clusters of students: urban upper-middle-class, immigrant working-class, and rural working-class. The urban upper-middle-class students experienced problems decoding new requirements and were troubled by blurred boundaries between school and home. This group invests the most in schooling, and therefore expresses comparatively more anxiety for reaching anticipated achievements. Immigrant working-class students were comparatively more discontented by a lack of school support | 551 LIDEGRAN Et AL.

We seek to consider the use of Pierre Bourdieu's 'cultural capital' within Swedish sociology of education focusing on the adoption of the term and asking how the 'cultural capital' is related to the specific context in Sweden. Here we consider the historical context and disciplinary route through which the concept travelled. The Swedish educational system promoted the ideal of meritocracy: everyone had an equal chance to access education, which in turn should facilitate social mobility. Even if the economic barriers to accessing education had been removed and higher education was available, social equality had not been achieved. The concept of cultural capital allowed for precise analyses of social groups' use of the education system. The studies were able to show that the meritocratic ideal also concealed an inequality, where the school's embrace of culture was something different from, and more than, what the teaching was supposed to convey.