Thermal gravimetric analysis (TGA) has been used for decades to study the thermal decomposition of cellulose. Unfortunately, reported kinetic parameters extracted from TGA‐based datasets for cellulose pyrolysis vary greatly; activation energies between 166 and 250 kJ/mol have been reported. In addition to heat and mass transfer limitations and source of biomass, which have previously been used to explain such variations, this work shows that the choice of regression objective function and optimization strategy are also important factors. Taking all into consideration, the activation energy of slow pyrolysis of microcrystalline cellulose was estimated to be 199 ± 2.0 kJ/mol.

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Kinetic models for pyrolysis of switchgrass and tall fescue were obtained using thermogravimetric analysis and a newly proposed parameter-extraction methodology. The optimization strategy demonstrates the use of the Akaike information criterion for the statistical identification of the number of distinct processes and a robust global search method. The effects of sample mass, heating rates, particle size, and crystallinity index on the kinetic parameters of each feedstock were considered. For whole biomass particles, the kinetic parameters of the cellulose component was found to be similar to that of pure microcrystalline cellulose. Further particle size reduction through extensive milling reduced the activation energy of cellulose by 48%. X-ray diffraction indicated that the cellulose fraction of highly milled whole biomass becomes largely amorphous and that the amorphization of the cellulose, not the particle size reduction, is likely responsible for the decrease in activation energy.

In Three Essays on the Theory of Sexuality, Freud (1986) wrote of a relationship between hysteria and sexuality and commented that hysteria was precipitated by the onset of a real sexual situation. Here, the scores on a measure of hysteria and sexual fantasies of student women who were (n ϭ 93) and were not (n ϭ 26) intercourse active were compared. Women who were intercourse active had higher scores on the PDQ4ϩ Histrionic scale (Hyler, 1994), p Ͻ .0001, and higher scores on Wilson's Total Sexual Fantasies (Wilson, 1988), p Ͻ .0001. In contrast, the PDQ4ϩ Obsessiveness scale (Hyler, 1994) scores of women in the 2 groups did not differ, p ϭ .65. The results provide empirical support for a relationship between hysteria and sexuality.