DCA - Artigos em Revistas Internacionais / Articles in International Journals
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- The Cave-Dwelling Ground Beetles on the Azores (Col.: Carabidae)Publication . Borges, Paulo A. V.; Oromí, PedroIn the present paper, the taxonomy of endemic species of "Thalassophillus" and "Trechus" from the Azores is studied, and the ecology, biogeography and possible evolution of these beetles are briefly discussed.
- The thermal conductivity of 1-chloro-1,1-difluoroethane (HCFC-142b)Publication . Sousa, Ana T.; Fialho, Paulo; Nieto de Castro, Carlos A.; Tufeu, R.; Le Neindre, B.The thermal conductivity of 1-chloro-l,l-difluoroethane (HCFC-142b) has been measured in the temperature range 290 to 504 K and pressures up to 20 MPa with a concentric-cylinder apparatus operating in a steady-state mode. These temperature and pressure ranges cover all fluid states. The estimated accuracy of the method is about 2 %. The density dependence of the thermal conductivity has been studied in the liquid region.
- Density of HCFC 142b and of its mixture with HCFC 22Publication . Sousa, Ana T.; Fialho, Paulo; Nieto de Castro, Carlos A.; Tufeu, R.; Le Neindre, B.The density of the binary mixture 40/60 wt% of monochlorodifluoromethane (HCFC 22) and 1-chloro-1,1-difluoroethane (HCFC 142b) in the liquid phase, has been measured between 300 and 370 K and pressures up to 19 MPa, with an oscillating fork sendimeter, operating in a relative mode. Toluene and vacuum have been used as calibrating fluids. The accuracy of the data is 0.08 %. An equation for the dependence of density in temperature and pressure for HCFC 142b and for this mixture is also presented.
- First records for the mesocavernous shallow stratum (M.S.S.) from the Azores.Publication . Borges, Paulo A. V.During a pitfall survey accomplished in the Azores by the author in 1989, 1990 and 1991 (see BORGES, 1992a and in prep.), the mesocavernous shallow stratum - M.S.S. ["Milieu Souterrain Superficiel" sensu JUBERTHIE (1983)] was investigated. The field work in St. Maria was done during the Zoological Expedition of the University of Azores (Department of Biology) between 11th and 19th June 1990. The presence of the M.S.S. in volcanic islands was only previously described from the Canary Islands (see MEDINA, 1991), also belonging to the same biogeographical region of the Azores, the Macaronesia. The existence of this habitat (in that time named "Superficial Underground Compartment") in the Canary islands was first cited by OROMÍ et aI., only in 1986. The first record of a troglobite from the Azorean M.S.S. was made by BORGES and OROMÍ (1991), refering the presence of the ground-beetle "Trechus terceiranus" Machado in this habitat of Terceira Island. The goal of the current work is to present a preliminary overview on the occurrence of the mesocavernous shallow stratum (sensu ASHMOLE et al, 1990) in two Azorean islands, the geologically young island of Terceira (0.30 m.y.) (FERAUD et al., 1980) and the oldest island of the archipelago, S. Maria (8.12 m.y.) (ABDEL-MONEM et al., 1975).
- New taxa of Poecilini (Coleoptera, Carabidae, Pterostichinae) from the Azores.Publication . Borges, Paulo A. V.; Serrano, Artur R. M.A new genus (Cedrorum n. gen.), a new species (C. azoricus n. sp.) including its nominate subspecies (C. a. azoricus) and a new subspecies (C. a. caveirensis n. ssp.) of Poecilini are described (Coleoptera, Carabidae, Pterostichinae), collected during a pitfall survey in the Azorean Climax pattern of autochthonous forest from the Terceira island (1989-1991) and during the Expeditions "Santa Maria e Formigas 90" (June 1990) and "Laurel-Pico 92" (July 1992) to the islands of S. Maria and Pico respectively. Some comments on the systematic, distribution and origin of the new taxa are made. The seasonality of the Terceira population is also presented.
- Thermophysical properties of alkali metal vapours. Part I.A - prediction and correlation of transport properties for monatomic systemsPublication . Fialho, Paulo; Ramires, Maria de Lurdes V.; Fareleira, João M.N.A.; Nieto de Castro, Carlos A.New calculations of the collision integrals for the singlet potential functions involved in the determination of viscosity, thermal conductivity and self-diffusion coefficients of the monatomic alkali metal vapours are presented. An interpolation procedure for the calculation of the monatomic systems transport coefficients in a large temperature range is provided. This is based on temperature correlations of the collision integrals for the singlet and triplet potential functions. The calculations have been carried out using a new potential function for the ground singlet state of the alkali diatomics. This is a recent version of the Extended Hartree-Fock Approximate Correlation Energy (EHFACE2U), proposed by Varandas et al., which is believed to give a correct description of the potential energy to vanishing internuclear distances. The results which are compared with previous calculations, are intended to be utilized in Part II of this paper in order to assess available experimental data on the viscosity and thermal conductivity coefficients of the alkali metal vapours.
- Thermophysical properties of alkali metal vapours. Part II - assessment of experimental data on thermal conductivity and viscosityPublication . Fialho, Paulo; Ramires, Maria de Lurdes V.; Nieto de Castro, Carlos A.; Fareleira, João M.N.A.; Mardolcar, Umesh V.An analysis of the available data on the viscosity and thermal conductivity coefficients of the alkali metal vapours is presented. The analysis is based upon theoretical calculations of the properties of the monatomic systems, described in the preceding parts I and I.A of the present paper, and making use of the kinetic theory of a binary gas reacting mixture. A summary of the measurement techniques used, including, whenever possible, the magnitude of the corrections performed on the raw data and the nominal precision of the results, complements the analysis. It is concluded that it is possible to select precise and mutually consistent sets of experimental results for both viscosity and thermal conductivity coefficients of lithium, sodium and potassium vapours among the available literature data and to classify all the data in uncertainty classes. Regarding rubidium and cesium no systematic discussion is possible due to a lack of experimental data with sufficient precision.
- The density of 1,1-dichloro-1-fluoroethane (HCFC 141b).Publication . Sousa, Ana T.; Fialho, Paulo; Nieto de Castro, Carlos A.In this Note we present the density of HCFC 141b, measured between 293.15 and 300.15 K, with an mechanical oscillator densimeter, with an uncertainty of 0.007%. The results are compared with the densities estimated by the reduced hard-sphere-DeSantis equation of state and with the experimental data obtained by several authors.
- Characterization of in situ dry matter and protein degradation of green and ensiled oats forages at three stages of growthPublication . Borba, Alfredo Emílio Silveira de; Ribeiro, João Ramalho
- Seasonal Activity of a Ground-Beetle (Coleoptera: Carabidae) Assemblage in a remnant of a Salty-Lake from Terceira (Azores).Publication . Borges, Paulo A. V.Ground-beetle species were sampled on the remnant of a salty-lake from Terceira (Azores) during one year using pitfall trapping. Three strongly hygrophilous species were found to be dominant: Notaphus (s. str.) semipunctatus (Donavan, 1806), Omaseus aterrimus nigerrimus Dejean, 1828 and Agonum marginatum (Linnaeus , 1758). The former and top dominant one, N. semipunctatus, is a new record for the Azores and Macaronesia. The activity density peak of these dominant species occurred in July. Thus, a «spring-breeder» ground-beetle guild was found to be characteristic of this heterogeneous sally biotope.