Citronella essential oil has more than eighty components, of which the most important ones are citronellal, geranial and limonene. They are present at high concentrations in the oil and are responsible for the repellent properties of the oil. The oil was extracted using supercritical carbon dioxide due to the high selectivity of the solvent. The operational conditions studied varied from 313.15 to 353.15 K for the temperature and the applied pressures were 6.2, 10.0, 15.0 and 180.0 MPa. Better values of efficiency of the extracted oil were obtained at higher pressure conditions. At constant temperature, the amount of extracted oil increased when the pressure increased, but the opposite occurred when the temperature increased at constant pressure. The composition of the essential oil was complex, although there were several main components in the oil and some waxes were presented in the extracted oils above 10.0 MPa. The results were modeled using a mathematical model in a predictive way, reproducing the extraction curves over the maximum time of the process

Este artigo apresenta a análise das manifestações da crise adolescência na correlação que estas mantêm com o funcionamento social contemporâneo como indicador privilegiado para pensar a operação da ciência e seus efeitos no campo do sujeito. A análise parte do exame da incidência da ciência sobre a linguagem como domínio a partir do qual o sujeito se constitui. Aborda questões próprias da clínica psicanalítica com adolescentes - tais como a dificuldade de elaboração de uma referência à alteridade e seus impasses diante do sexo e a morte -, refletindo sobre a vinculação destas dificuldades com o que é desencadeado pelas transformações do discurso e do laço social constitutivas da prática da ciência.