Search results for "Allium"
showing 10 items of 385 documents
CCDC 906037: Experimental Crystal Structure Determination
2013
Related Article: B.P.Waldron, D.Parker, C.Burchardt, D.S.Yufit, M.Zimny, F.Roesch|2013|Chem.Commun.|49|579|doi:10.1039/c2cc37544c
CCDC 906038: Experimental Crystal Structure Determination
2013
Related Article: B.P.Waldron, D.Parker, C.Burchardt, D.S.Yufit, M.Zimny, F.Roesch|2013|Chem.Commun.|49|579|doi:10.1039/c2cc37544c
High‐Quality Si‐Doped β‐Ga 2 O 3 Films on Sapphire Fabricated by Pulsed Laser Deposition
2020
The EU Horizon 2020 project CAMART2 is acknowledged for partly supporting the project, and the Ion Technology Centre, ITC, in Sweden is acknowledged for ion beam analysis (ERDA).
Structural, optical, and luminescence properties of ZnO:Ga optical scintillation ceramic
2018
This paper discusses the characteristics of ZnO and ZnO:Ga ceramics fabricated by uniaxial hot pressing. The short-wavelength transmission limit of zinc oxide ceramics is in the 370-nm region; the long-wavelength limit is determined by the free-charge-carrier concentration and lies in the interval from 5 to 9 μm. The total transmittance of such ceramics in the visible and near-IR regions is about 70% when the sample is 0.5 mm thick. The luminescence spectrum is represented by a broad emission band with maximum at 580 nm, having a defect nature. The introduction of 0.03–0.1 mass % gallium into the zinc oxide structure inhibits grain growth and increases the free-charge-carrier concentration …
Barrier inhomogeneity in vertical Schottky diodes on free standing gallium nitride
2019
Abstract In this paper, the electrical behavior of a Ni/Au Schottky barrier on free standing GaN has been studied employing a variety of techniques and correlated with the material and interface quality. The temperature dependence of the ideality factor (n) and of the Schottky barrier height (ΦB) revealed a spatial inhomogeneity of the barrier. This behavior has been described by means of the Tung's model on inhomogeneous Schottky barriers. The origin of the barrier inhomogeneity can be likely associated to the surface quality of the GaN epilayer or to microstructure of the Ni/GaN interface.
Current Spreading Length and Injection Efficiency in ZnO/GaN-Based Light-Emitting Diodes
2019
We report on carrier injection features in light-emitting diodes (LEDs) based on nonintentionally doped-ZnO/p-GaN heterostructures. These LEDs consist of a ZnO layer grown by chemical-bath deposition (CBD) onto a p-GaN template without using any seed layer. The ZnO layer (~1- $\mu \text{m}$ thickness) consists of a dense collection of partially coalesced ZnO nanorods, organized in wurtzite phase with marked vertical orientation, whose density depends on the concentration of the solution during the CBD process. Due to the limited conductivity of the p-GaN layer, the recombination in the n-region is strongly dependent on the spreading length of the holes, ${L}_{h}$ , coming from the p-contact…
Allium nazarenum (Amaryllidaceae), a new species of the section Codonoprasum from Israel
2017
Allium nazarenum, a new species of A. sect. Codonoprasum, is described and illustrated from Israel. Within this species, two well distinct subspecies have been recognized, represented by the subsp. nazarenum and subsp. ramonense respectively. The first one occurs in northern and central Israel, which falls within the Mediterranean bioclimate, while the second one is circumscribed to the Negev desert. Both taxa are diploid with 2n = 16 and are found on various substrata usually in the batha or steppic plant communities. This species shows close relationships with the species belonging to the A. staticiforme group, from which it differs in several relevant diacritic features. Its morphology, …
Interspecific variation of inflorescence scents and insect visitors in Allium (Amaryllidaceae: Allioideae)
2019
Allium is a large monocotyledonous genus, with many species of high economic importance. Knowledge of the pollination biology and the chemical ecology of pollination in this genus is far from being complete. We studied flower visitors of some Allium species in their native habitat and how these interaction partners communicate by olfactory cues. Floral volatiles of five Mediterranean species were investigated by dynamic headspace and thermal desorption-gas chromatography/mass spectrometry (TD-GC/MS). Floral visitors were observed and captured. The physiological activity of scent components in antennae of flower visitors and congeneric species was tested by gas chromatographic/electroantenno…
Allium istanbulense, a new autumnal species of A. sect. Codonoprasum (Amaryllidaceae) from Turkey and its taxonomic position among allied species
2018
Allium istanbulense, a new species of Allium sect. Codonoprasum, is described and illustrated from Istanbul surroundings (European Turkey). It is a late-flowering diploid species (2n = 16), occurring in the undergrowth of oak or pine woods mainly on sandy or incoherent soils. Its morphology, karyology, leaf anatomy, seed micromorphology, ecology, conservation status and taxonomic relationships are examined. A taxonomic comparison with the most allied late flowering species of sect. Codonoprasum and identification keys of the group are also provided.
An inventory of the names of native, non-endemic vascular plants described from Italy, their loci classici and types
2019
The census of the loci classici of 1,227 native, non-endemic vascular plants described from Italy is here presented and described. The effective place of publication of accepted names, basionyms and homotypic synonyms were identified and critically verified. The geographic information on the loci classici was excerpted from the protologues, as well as information on typification for the taxa described before 1 January 1958. The names without a holotype are 1,165. For 591 names a lecto- or neo-typification is available in literature, while 572 currently accepted taxa still need a type designation. For ten of these names showing previous ineffective typification, nomenclatural types are desig…