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  • Author or Editor: C. Ramos x
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Three new species in the genus Esenbeckia Kunth ( E. bicolor, E. stephani, E. velutina ) are described, E. ovata is reconsidered and E. collina subsp. conspecta is elevated to species rank based on a new concept evolved by the author, different from that of Kaastra (1977, 1982).

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Esenbeckia dorantesii, a new species in the genus Esenbeckia Kunth (Rutaceae) is described. This species from the coastal zone of the state Veracruz, Mexico, is similar to E. macrantha Rose from the state of Oaxaca.

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Attilaea abalak is described. This species belongs to the new Attilaea genus in the Anacardiaceae family. Its principal characters are the scandent habit and the bicarpelar gynoecium. Actually is only known from collections in limestone soils.

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A new species of Guettarda is described, at this time it has been collected only in the type locality. It is similar to the Mesoamerican species G. tikalana Lundell.

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Se describe una nueva especie del genero Esenbeckia (Rutaceae) de la cuenca baja del rio Balsas, en la llamada “Tierra Caliente”.

A new species of the genus Esenbeckia (Rutaceae) is herein described; it was found in the lower Balsas River basin, in the zone referred to as “Tierra Caliente”.

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Abstract  

We investigated the features of the glass transition relaxation of two room temperature ionic liquids using DSC. An important observation was that the heat capacity jump, that is the signature of the glass transition relaxation, shows a particularly strong value in this type of new and promising materials, candidates for a range of applications. This suggests a high degree of molecular mobility in the supercooled liquid state. The study of the influence of the heating rate on the temperature location of the glass transition signal, allowed the determination of the activation energy at the glass transition temperature, and the calculation of the fragility index of these two ionic glass-formers. It was concluded that this kind of materials belong to the class of relatively strong glass-forming systems.

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Esenbeckia vazquezii, a new species of Esenbeckia Kunth (Rutaceae) with round fruit is described. It was found in the Spa “El Texcal” located in the Chichinautzin lava beds near Cuernavaca, Morelos. Because it is growing in an urbanised area, probably it is endangered.

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Abstract  

In the search of a useful method for determining excess enthalpies as a function of temperature Calvet calorimetry was employed. To this end, excess molar enthalpies

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at 298.15 and 333.15 K and excess molar heat capacities
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within 283.15–333.15 K were determined for the 1-decanol+n-decane system over the whole composition range. An isothermal flow Calvet-type calorimeter was used for
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measurements, whereas
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were determined by means of a Setaram Micro DSC calorimeter. Excess enthalpies within 283.15–333.15 K were indirectly obtained through the integration of
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(T) data using
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at 298.15 K. The results obtained at 333.15 K agreed with those determined directly, implying the thermodynamic consistency of the measured data and, therefore, the reliability of the indirect method.

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Se describe una nueva especie del género Esenbeckia Kunth (Rutaceae) procedente del Istmo de Tehuantepec, México. Esta nueva especie se encontró conviviendo con E. collina Brandegee.

A new species in the genus Esenbeckia (Rutaceae) from the Tehuantepec Isthmus, Mexico – A new species in the genus Esenbeckia Kunth (Rutaceae) is described. This species from the Tehuantepec Isthmus, Mexico is sympatric with E. collina Brandegee.

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A new species of Chomelia is described; at this time it has been collected only at the type locality. It is similar to the Mexican–Mesoamerican species Chomelia longituba (Borhidi) Borhidi, but can be easily distinguished by the position of the inflorescence, by the form of the stigma lobes and the size of the fruit.

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