In deze publicatie staan de verhalen van drie Poolse mannen in Den Haag centraal. De onderzoeker, Karijn Nijhoff, heeft zeer intensief deze mannen gevolgd en hun verhalen opgetekend. We lezen over aankomst, vertrek en terugkomst. We zien een grillig proces van werken en niet werken, klussen en diverse vormen van inkomensverwerving. De werkelijkheid heeft tinten wit, zwart en grijs. Integratie, een veel gebezigd woord in de wereld van bestuur en beleid, ziet er soms heel anders uit dan het geplande en gefaseerde proces op papier. There is also an English version of this report in this database: "Fluidity of bounderies".
A kinetic model for the formation of acrylamide in a glucose-asparagine reaction system is proposed. Equimolar solutions (0.2 M) of glucose and asparagine were heated at different temperatures (120-200°C) at pH 6.8. Besides the reactants, acrylamide, fructose, and melanoidins were quantified after predetermined heating times (0-45 min). Multiresponse modeling by use of nonlinear regression with the determinant criterion was used to estimate model parameters. The proposed model resulted in a reasonable estimation for the formation of acrylamide in an aqueous model system, although the behavior of glucose, fructose, and asparagine was slightly underestimated. The formation of acrylamide reached its maximum when the concentration of sugars was reduced to about 0. This supported previous research, showing that a carbonyl source is needed for the formation of acrylamide from asparagine. Furthermore, it is observed that acrylamide is an intermediate of the Maillard reaction rather than an end product, which implies that it is also subject to a degradation reaction.
