Browsing by Issue Date, starting with "1996"
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- As crises de mortalidade no concelho de Évora na segunda metade do século XIXPublication . Mendonça, Alice Maria Ferreira
- Small-amplitude solitons in a nonlocal sine-Gordon modelPublication . Cunha, M. D.; Konotop, V. V.; Vázquez, L.It is shown that small amplitude solitons of a nonlocal sine-Gordon model corresponding to different frequencies of the carrier wave can create coupled states. The effect is due to a change of the dispersion originated by a nonlocal nonlinearity. Within the framework of the multiscale expansion such pulses are described by a system of nonlinear Schtidinger equations which possesses coupled mode solutions in the form of running localized waves (breathers). Such breathers consist of modes with different frequencies and are characterized by two internal frequencies.
- La pêche à la senne de plage à Nazaré, Portugal: systèmes techniques et sociaux d`exploitationPublication . Escallier, Christine
- Contra a unicidade curricularPublication . Fino, Carlos Nogueira
- Isolation and characterization of a lignin-like polymer of the cork of Quercus suber LPublication . Neto, C. Pascoal; Cordeiro, N.; Seca, A.; Domingues, F.; Gandini, A.; Robert, D.A lignin-like polymer was successfully extracted from the cork of Quercus suber L. using an organosolv-based technique. This material was characterized by elemental analysis, functional group analysis, nitrobenzene oxidation followed by HPLC analysis of the oxidation products, FTIR and liquid I3C NMR. The evidence thus obtained indicated that the extracted material was composed mainly of a lignin-like polymer covalently bound to residual aliphatic structures which are not present in common lignins and which have been assigned to suberin. The latter is likely to be attached to the oxygenated side chains of the phenolic polymer but bonding through the aromatic ring can also be envisaged. No residual carbohydrates were detected. The phenolic polymer, composed mainly of guaiacyl-type units and small amounts of syringyl-type units, had a low methoxy content and a high degree of condensation. This polymer showed the presence of a fraction containing CeCn units with n < 3 or even n < 2.
- A integração de alunos com necessidades educativas especiais e a formação de professoresPublication . Pocinho, Margarida Maria Ferreira Diogo Dias
- Parasites of the black scabbard fish Aphanopus carbo Lowe, 1839 from MadeiraPublication . Costa, G.; Eiras, J. C.; Mckenzie, K.; Berland, B.In ninety specimens of black-scabbard fish, Aphanopus carbo, examined from October 93 to October 94, five different helminth parasites and a myxosporean species were found infecting the digestive tract and gonads. Larval stages of Eucestoda, Trypanorhyncha, Tentacularia coryphaenae Bosc, 1802, Sphyriocephalus tergestinus Pintner, 1913 and Nybelinia lingualis (Cuvier, 1817) Poche, 1926 were found infecting the stomach mucosa, with prevalences reaching 13.3%, 5.6% and 3.3% respectively. Larval stages of the acanthocephalan Bolbosoma sp. Porta, 1908 (probably Bolbosoma vasculosum Rudolphi, 1819) attached to the external wall of stomach, intestine and gonads reached a prevalence of 45.6% and larval stages of the nematode Anisakis sp. Dujardin, 1845 was found infecting the viscera of all the fish examined, particularly the external walls of stomach and intestine. Spores and plasmodial stages of the myxosporean, Ceratomyxa tenuispora Kabata, 1960 were found in the gall bladder, with prevalence reaching 39.4%. All parasites, except the myxosporean, are first records for the black-scabbard fish.