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Separation techniques are usually presented in the undergraduate organic laboratory to teach students how to purify and isolate compounds. Often the concept of liquid chromatography is introduced by having students create "silica gel columns" to separate components of a reaction mixture. Although useful, column chromatography can be a laborious technique for students to perform. The separation efficiency can be compromised if students do not prepare the column correctly, and the time required to separate substances can extend beyond a typical laboratory period. Herein, the use of radial chromatography (centrifugal thin-layer chromatography) as an alternative to the traditional column chromatography technique utilized in many teaching laboratories is discussed. Radial chromatography can be used to introduce the principles that underlie liquid chromatography, with the added benefit of providing a relatively fast and highly efficient separation. An experiment for the efficient separation of a mixture containing 2-nitroaniline and 3-nitroanilne using radial chromatography is presented. Typical student results show that each substance can be collected with a high percent recovery ([approxiamately 70-80%). Furthermore, the melting range of each isolated substance is found to be in agreement with literature values. The separation can be completed in 40-50 min once the sample has been loaded. (Contains 1 figure.)

Major theories of single-party dominance underestimate the causality with which citizens, in their discontents, and electoral contests, in heightening these grievances, can advance democratic change. In their factor sequencing, these theories prioritize economic crisis, the party's loss of patronage resources, elite-level defections, and correspondingly invigorated opposition parties. But this fails to account for recent events in Malaysia wherein the United Malays National Organization (UMNO), long dominating politics, was recently dealt so striking an electoral setback that a democratic transition appeared to have begun. This article demonstrates, then, that change, especially in the wake of the government's pledges to reform, was initiated by citizens, alienated over precisely the patronage resources by which UMNO had perpetuated its dominance. They were animated also by the manipulations of elections, further encouraging them to vote with new determination. Throughout, this article shows that in gauging the motivations of citizens to initiate change, their perceptions of the government's legitimacy, involving institutional conformity, and policy performance offer a useful analytical tool. Keywords: Malaysia, Legitimacy, Democratic Transition, Single-Party Dominance, Elections. Importantes teorias del predominio del partido unico en Malasia subestiman la causalidad con la que los ciudadanos, en su descontento, y los fraudes electorales que lo aumentan considerablemente, pueden promover el cambio democrdtico. En la secuencia de esosfactores, estas teorias dan prioridad a la crisis economica, la perdida del partido de fuentes de apoyo, las deserciones de la elite, y la vigorizacion proporcional de lospartidos de oposicion. Estas teorias omiten tomar en cuenta los eventos recientes en Malasia donde las politicas de predominio de la Organizacion Nacional Malaya Unida (UMNO, por sus siglas en ingles) sufrieron recientemente un reves tan asombroso que parece que ha dado inicio a una transicion democrdtica. Este articulo demuestra, entonces, que el cambio, justo cuando el gobierno habia prometido reformarse, fue iniciado por los ciudadanos, motivados principalmente por el agravio que les provocaba el dispendioso patronazgo clientelar con el que la UMNO habia venido perpetuando su dominio. Los ciudadanos tambien resintieron la manipulation electoral, lo que los alento aun mds a votar por una nueva administracion. Este articulo demuestra que una util herramienta analitica es considerar las motivaciones de los ciudadanos para iniciar el cambio y sus percepciones de la legitimidad del gobierno que involucran tanto la conformidad institutional asi como el desempeno de las politicas., Although a useful analytical tool, the notion of political legitimacy is imprecise, subjective, and often tautological. But in applying it to Malaysia, we may nonetheless discover some unique utility. Alone [...]