81,332 research outputs found
Entraves d'amour : valse pour piano / A. Cervi
No full textTitre uniforme : Cervi, A. (18..-19.. ; compositeur). Compositeur. [Entraves d'amour. Piano]Valses (piano) -- +* 1900......- 1999......+:20e siècle:Piano, Musique de -- +* 1900......- 1999......+:20e siècle
CARATTERIZZAZIONE ELETTRICA E SPETTROSCOPICA AD IMPEDENZA DI OSSIDI METALLICI NANOSTRUTTURATI PER IL RILEVAMENTO DI ALCANI VOLATILI
No full textChemoresistive gas sensors using semiconductor metal-oxides have proven to be excellent in important characteristics such as sensitivity, long-term stability, robustness and price. Solid solutions of mixed Sn and Ti oxides have shown promising results in combining the properties of the separate components. Basic science of these mixed oxides is far from being satisfactorily elucidated. Further progress in basic understanding is required to establish the principles to operate them as gas sensors.
Knowledge of the space charge width of the nanostructured powder grains is needed for the comparison of the mean grain radius to determine sensing properties of the nanostructure. A new method has been addressed using impedance spectroscopy technique to estimate the electric permittivity of these Sn and Ti oxides, which is fundamental for the determination of the space charge width and capacitive response.
A study of the sensing properties of chemoresistive metal-oxides vs. light alkanes has been undertaken under dry and wet conditions and even in presence of ethanol. Screen-printed films of pure Sn and Ti oxides and solid solutions of mixed Sn and Ti oxides have been selected for the purpose. It has been demonstrated that the films are capable of detecting 500ppm of methane or 100ppm of other light alkanes under either dry or wet condition, i.e. concentrations two levels by far lower than the alarm thresholds for such gases. Information about the working mechanism of chemical reactions on the surface has been discussed under either dry or wet condition. Ethanol is known to be a harmful interfering gas, though its concentration can be reduced to values lower than 10ppm by proper activated carbon filtering. It has been shown that, even in presence of 10ppm of ethanol, the films steadily responded to alkanes
Stability analysis of the Generation-IV nuclear reactors by means of the root locus criterion
No full textPassiflora junqueirae Imig & Cervi 2014, sp. nov.
No full textPassiflora junqueirae Imig & Cervi, sp. nov. (Fig. 1 A–G) Diagnosis: –– Passiflora amethystina et P. loefgrenii similis sed lobulis foliorum oblongo-lanceolatis et absentis glandulis in sinubus, alternatis bracteis, corona 7 seriebus filamentorum disposita, petalis et sepalis albis cum maculis lilacinis differt. Type: –– BRAZIL. Espírito Santo: National Park of Caparaó, 20°28’22,14”S, 41°49’ 30,23”W. s.d. Cultured stakes at EMBRAPA CERRADOS, Planaltina –DF, 03 February 2014, D. C . Imig; N. T. V. Junqueira & F. C. Pinheiro 296 (Holotype MBM!, Isotypes UPCB!, RB!; VIES! MBML!). Vine, herbaceous, sparsely hairy, especially on the petioles, young stems, peduncles, flower buds and outer surface of calyx tube, with usually inconspicuous trichomes, 0.4–1.0 mm long. Stem cylindrical, striate, light green. Stipules persistent, reniform, 1.3–2.2 x 0.4–0.6 cm, inserted laterally on the stem, membranous, apex acute to acuminate, base asymmetric, margin entire, glabrous, glaucous on abaxial surface. Leaves with cylindrical petioles 3.0– 5.5 cm, grooved on adaxial surface, 3.0– 5.5 cm with 3–6 stipitate glands, usually 3–4 glands dispersed from the middle portion of petioles, and 2 glands near the blade. Blades 3-lobed, oblong-lanceolate lobes, median lobe 5.0–9.0 x 1.0– 1.5 cm, lateral lobes 5.0–7.5 x 0.7–1.4 cm, divaricate to slightly ascending, margin entire and without glands in the sinus, apex obtuse to acute, acuminate, base truncate and sub-peltate, petiole inserted 1.4–2.3 mm from the base into the blade, membranous, glabrous, glaucous on abaxial surface, three main veins from the base, secondary veins reticulate. Tendrils well developed, thin, glabrous or sparsely hairy at the base. Peduncles solitary, 4.5–9.5 cm, pedicel 0.5–0.8 cm. Bracts alternate, linear, 0.3–0.5 cm, inserted from the median portion, alternating 0.8–1.0 cm from each other, apex acute, base truncate, margin entire, membranous, early deciduous, leaving discrete brown scar. Flowers 7.0– 10.5 cm diam.; calyx tube campanulate, 0.4–0.5 x 0.8–1.0 cm, outer surface sparsely hairy, glaucous; sepals oblong-lanceolate 2.0–2.3 x 0.4–0.5 cm, fleshy, concave, apex obtuse, abaxial surface light green, sparsely hairy, apex acute, dorsal awns 2.0– 3.4 cm, adaxial surface white with slight lilac nuances; petals oblong-lanceolate, 2.0–2.7 x 0.7–0.9 cm, membranous, apex obtuse, white on both faces, with slight lilac nuances on adaxial surface. Corona of filaments in seven unequal series, filaments of outer series cylindrical, 1.0– 1.4 cm long., radiating, dark purple at the base, one white band in the middle portion, followed by light lilac to white at the apex; filaments of second series flattened at the base, the upper third filamentous until the apex (awl-shaped), radiating, 1.0– 1.4 cm long., dark purple at the base, with one white band in the middle portion, followed by light lilac to white at the apex; the remaining five series of filaments threadlike, (0.3) 0.5–0.7 cm long., capitate or bilobed at the apex, dark purple, erect; operculum membranous at the base, 1.0– 1.5 mm, followed by a filamentous portion with 4.0– 4.5 mm, apex of the membranous portion slightly plicate, with dentiform projections on the base of the filamentous portion, facing the inner side of the calyx tube, erect filamentous portion, bordering the androgynophore, with filaments capitate or bilobed at the apex, dark purple; nectariferous ring membranous, 0.1–1.5 mm long., revolute at the apex; limen membranous, ca. 0.5 cm, adhering to the androgynophore, free portion ca. 0.1 cm, projecting horizontally and wavy at the apex. Androgynophore 1.3–1.5 cm long., light green spotted with purple; staminal filaments 0.6–0.8 cm long., light green spotted with purple; styles ca. 0.6 cm long., light green spotted with purple. Ovary oblong, tomentose, usually covered by yellowish trichomes. Fruits berries, elliptical, yellowish green when ripe, sparsely hairy. Seeds obovate, 0.5 x 0.3 cm, rigid, toothed at the apex, dark brown, deeply reticulated. Aril transparent, with slightly acidic flavor. Etymology: —The epithet honors Dr. Nilton Tadeu Vilela Junqueira, researcher in Embrapa Cerrados-Planaltina, DF. Distribution and habitat: — Passiflora junqueirae is known only from Espírito Santo state, in Brazil, in the National Park of Caparaó, in elevations from 1,400 to 2,100 m. In nature, the flowers reach anthesis in the morning. Paratypes: — BRAZIL. Espírito Santo. National Park of Caparaó, 20°28’22”S, 41°49’30”W. 2100m elev., 19 December 2011, D. C . Imig & A. C. Cervi 45 (HACC!- Centro Universitário Campos de Andrade, not indexed); ib., 10 August 1999, F . C. Campos Neto s.n. (CEN!); ib., 17 September 2013, F . C. Campos Neto s.n. (CEN!, UPCB!, HRJ!, UB!, NY!, MO!, BHMH!, FLOR!, ACCH!); Cultured stakes at EMBRAPA CERRADOS, Planaltina –DF, 31 January 2014, F . C. Pinheiro & N. T.V. Junqueira 844 (VIES!; HCF!); ib., 24 December 2013, N . T.V. Junqueira s.n. (CURD!; UPCB!). Discussion: — Passiflora junqueirae Imig & Cervi is morphologically similar to P. amethystina J.C. Mikan (1825: 37) and P. loefgrenii Vitta (1997: 210), but several characteristics distinguish these species. P. junqueirae is a plant sparsely hairy, leaves are 3–lobed and the lobes are oblong-lanceolate, the base of the blade is sub-peltate and without glands in sinus. The bracts are linear and alternate. It has seven series of filaments in the corona, the second series of filaments are flattened from the base to the middle portion, and filamentous until the apex (awl-shaped). The sepals have dorsal awns 2.0– 3.5 cm long, petals and the adaxial side of the sepals are white, with discrete portions of pale lilac, ovary tomentose (Fig. 2, A–E). P. amethystina differs from P. junqueirae, being totally glabrous, except for the ovary, the 3-lobed leaves have lobes which are oval or elliptical, the base of the blade is cordate or subcordate and has glands in the sinus. The bracts are ovate or ovate-lanceolate and verticillate. Corona of filaments is in 4–5 rarely 6 series, with threadlike filaments, radially, not showing flattened expansion, the sepals have dorsal awns, but do not exceed 1.0– 1.5 cm, the petals and adaxial side of the sepals are purple. P. loefgrenii is vegetatively similar to P. amethystina, but differs from P. junqueirae, because the bracts are ovate-lanceolate, verticillate. FIGURE 1. Passiflora junqueirae. A. Detail of flower in abaxial surface; B. Habit and detail of flowering branch. C. Detail of a bract. D. Flower detail in longitudinal section. E. Detail of second series of filaments. F. Fruit. G. Seed. (A–G based on D.C. Imig et al. 296). Key to P. junqueirae and related species: 1. Blades with oblong-lanceolate lobes, glands absent in sinus, bracts linear and alternate, sepals and petals with the adaxial surface white with discrete portions of light lilac....................................................................................................................... P. junqueirae - Blades with elliptic to oval lobes, glands present in sinus, bracts ovate and verticillate, petals and sepals with the adaxial surface purple or lilac......................................................................................................................................................................................2 2. Ovary glabrous................................................................................................................................................................. P. loefgrenii - Ovary tomentose........................................................................................................................................................... P. amethystinaPublished as part of Imig, Daniela Cristina & Cervi, Armando Carlos, 2014, A new species of Passiflora L. (Passifloraceae), from Espírito Santo, Brazil, pp. 292-296 in Phytotaxa 186 (5) on pages 292-296, DOI: 10.11646/phytotaxa.186.5.7, http://zenodo.org/record/515379
Coupling geomorphic field observation and Lidar derivatives to map complex landslides.
No full textHigh resolution LiDAR DEMs from regional or site specific surveys were used to map complex landslides such as deep-seated rockslides and earth slides-earth flows. Regional surveys DEMs were used to produce shaded relief maps that allowed delimiting rock slide units and sub-units at the slope scale. Multitemporal site-specific survey DEMs were used in eath slides-earth flows case studies to derive roughness maps that allowed defining the curvature fingerprint of the most active parts of earth flows, and to derive differential elevation maps that allowed assessing depletion and accumulation areas occurring in the slope as a consequence of post-failure dynamics
Cheap Conic OPF Models for Low-Voltage Active Distribution Networks
Full text linkThe increasing focus on the active participation of low-voltage (LV) active distribution networks (DNs) in electricity markets requires the real-time optimal control of these DNs. To achieve this goal, a cheap semi-definite programming (SDP)-based optimal power flow (OPF) model for active neutral-equipped DNs, hosting both wye- and delta-connected loads, is proposed in this paper, aiming at overcoming the high computational requirement of the primal SDP-based OPF model. The coupled power injections between conductors are explicitly represented for each conductor by utilizing the network admittance matrix-based approach. Furthermore, three novel propositions (P1, P2 and P3) are proposed for the modelling of the constant current component of ZIP end-users in the context of the proposed OPF model. Moreover, the impact of the voltage-angle deviation on the exactness of the P1- and P2-based models is discussed. Simulations are carried out on several LV active DNs for various parameters of ZIP end-users, and the quality of the proposed OPF model is verified through the %optimality gap, power mismatch, voltage violation and root-mean-square error criteria. It is successfully shown that the proposed OPF model provides an optimal and feasible solution for all load types (wye, delta, mixed wye-delta) under a large range of ZIP load parameters. Furthermore, among the three propositions, the P3-based OPF model appears to be the most accurate in terms of determining an optimal and feasible solution. Finally, the reduced computational time of the cheap conic model allows its real-time implementation for medium- and large-sized DNs for which the primal multi-phase SDP-based model is practically difficulty to realize
A complete analytical solution to the integro-differential model for nucleation and evolution of crystals in a metastable system
Full text linkA nonlinear system of time-dependent integro-differential equations that describes the processes of phase transforma- tions in metastable melts and solutions is investigated. Using the saddle-point method for calculating the Laplace-type integral, a complete analytical solution was constructed, which determines the dynamic dependencies of the crystal size distribution function and the supercooling (supersaturation) of the system. The maximum size of the growing crystals, the average number of crystals and their average size as functions of time are found. It is shown that to correctly describe the evolution of a metastable system, it is necessary to take into account both the fundamental contribution of the saddle-point method and the following four contributions of the asymptotic expansion. The theory under consideration is in good agreement with experimental data. © 2019 Author(s).Russian Science Foundation, RSF: 18-19-00008This work was supported by the Russian Science Foundation (grant number 18-19-00008)
Centralized OPF in Unbalanced Multi-Phase Neutral Equipped Distribution Networks Hosting ZIP Loads
Full text linkAuthor and poet Lily Brett at the National Library of Australia, Canberra, 18 October 2012 /
No full textTitle from acquisitions documentation.; Part of the collection: Portraits of author and poet Lily Brett at the National Library of Australia, Canberra, 18 October 2012.; Acquired in digital format; access copy available online.; Mode of access: Online.; Photographed by a staff member of the National Library of Australia
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