1,730,850 research outputs found
New species and records of tree ferns (Cyatheaceae, Pteridophyta) from the northern Andes
No full textFour new species of Cyatheaceae from Ecuador are described: Alsophila conantiana Lehnert, Cyathea brucei Lehnert, C. moranii Lehnert, and C. sylvatica Lehnert. Range extensions are documented for Alsophila esmeraldensis R.C. Moran and Cyathea macrocarpa (C. Presl) Domin
New species and records of tree ferns (Cyatheaceae, Pteridophyta) from the northern Andes
No full textFour new species of Cyatheaceae from Ecuador are described: Alsophila conantiana Lehnert, Cyathea brucei Lehnert, C. moranii Lehnert, and C. sylvatica Lehnert. Range extensions are documented for Alsophila esmeraldensis R.C. Moran and Cyathea macrocarpa (C. Presl) Domin
Cyathea uleana Lehnert 2011
No full textCyathea uleana (Sampaio 1923: 65) Lehnert (2011b: 43) Distribution and habitat: — Colombia, Ecuador, Peru, Brazil and Bolivia.Published as part of Lehnert, Marcus, 2012, A synopsis of the species of Cyathea (Cyatheaceae-Polypodiopsida) with pinnate to pinnate-pinnatifid fronds, pp. 17-36 in Phytotaxa 61 (1) on page 32, DOI: 10.11646/phytotaxa.61.1.2, http://zenodo.org/record/506168
On the identification of Cyathea pallescens (Sodiro) Domin (Cyatheaceae): typifications, reinstatements and new descriptions of common Neotropical tree ferns
No full textBased on studies of type material collected by Sodiro, several Andean tree fern species formerly united in Cyathea pallescens (Sodiro) Domin are here distinguished: C. pallescens s.s. is an exindusiate species synonymous with C. halonata R.C.Moran & B.Ollgaard and is restricted to the western slopes of the Cordillera Occidental in southern Colombia and northern Ecuador. Reinstated species are C. brachypoda Sodiro, C. tungurahuae Sodiro and C. cystolepis Sodiro with var. cystolepis, var. boreopallescens Lehnert var. nov. and var. leonis Lehnert var. nov. from the northern Andes; Cyathea austropallescens Lehnert is newly described from the central Andes. New descriptions of all species and illustrations of important characters are given and several lectotypifications are made. Added in shorter descriptions for comparison are C. atahuallpa (R.M.Tryon) D.B.Lellinger, C. bettinae Lehnert, C. corallifera Sodiro, C. dintelmannii Lehnert, C. divergens (Baker) Domin, C. simplex R.M.Tryon, C. straminea H.Karst. and C. ruiziana Klotzsch (= C. boliviana R.M.Tryon). (C) 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 158, 621-649.EAP (Education Abroad Program
Cyathea bettinae (Cyatheaceae), a new tree fern from Bolivia
No full textLehnert, M. (Albrecht-von-Haller Institut, Abt. Systematische Botanik, Universitat Gottingen, Untere Karspule 2, 37073 Gottingen, Germany; email: [email protected]). Cyathea bettinae, a new tree fern from Bolivia. Brittonia 56: 210-212. 2004-A new species of Cyatheaceae is described and illustrated: Cyathea bettinae. It is a small tree fern from the mountain forest of northwestern Bolivia
Melpomene anazalea, a New Species of Grammitid Fern (Polypodiaceae)
No full textA new species of grammitid fern, Melpomene anazalen Sundue & Lehnert from Colombia, is described and illustrated. it stands out in the genus for its particularly small size and abundantly setose lamina. it is known from protected rock crevices in relatively dry paramos
Melpomene anazalea, a New Species of Grammitid Fern (Polypodiaceae)
No full textA new species of grammitid fern, Melpomene anazalen Sundue & Lehnert from Colombia, is described and illustrated. it stands out in the genus for its particularly small size and abundantly setose lamina. it is known from protected rock crevices in relatively dry paramos
Suggestion of Raspailia (Hymeraphiopsis) septentrionalis as replacement name for Raspailia (Hymeraphiopsis) fruticosa Lehnert & Stone, 2015
No full textLehnert, Helmut, Stone, Robert P. (2016): Suggestion of Raspailia (Hymeraphiopsis) septentrionalis as replacement name for Raspailia (Hymeraphiopsis) fruticosa Lehnert & Stone, 2015. Zootaxa 4092 (1): 139-139, DOI: 10.11646/zootaxa.4092.1.
Reconsideration of Alsophila odonelliana (Cyatheaceae), an Andean tree fern
No full textLehnert, M. (Albrecht-von-Haller Institut, Abt. Systematische Botanik, Universitat Gottingen, Untere Karspule 2, 37073 Gottingen, Germany; e-mail: [email protected]). Reconsideration of Alsophila odonelliana (Cyatheaceae), an Andean tree fern. Brittonia 57: 228-236. 2005. Two Andean tree fern species formerly united are hereby distinguished: Alsophila incana from Colombia, Ecuador, and Peru, and Alsophila odonelliana from southern Bolivia and northern Argentina. New descriptions of both species as well as illustrations of important characters are given. Vegetative reproduction by means of stolons is reported for an Andean species of the genus for the first time
Spectroscopic investigations of the H3PO4 and H2O uptake of polybenzimidazole membranes for fuel cells
No full textPolybenzimidazole (PBI) doped with H3PO4 is the most commonly used membrane material for high-temperature polymer fuel cells. Proton conductivity is strongly dependent on acid doping and water content (humidity). Despite these facts, only little is known on the chemical equilibria of all species inside the membrane as a function of the composition of the ternary system PBI - H3PO4 - H2O. This includes details on the proton transfer processes, on the dominant conduction mechanisms and on the condensation equilibria, leading to the formation of diphosphoric acid and higher homologues species.
In this study, Raman and NMR spectroscopy is used to investigate the chemical inter¬actions between H3PO4, H2O and PBI vs. the H3PO4 doping level. We obtained information on the H-bond formation between H3PO4 and the polymer chains, on tautomeric processes as well as on the presence of not directly bound H3PO4 at high doping levels. Investigations were performed with uncrosslinked and crosslinked m-PBI and AB-PBI [1-4]. [1] F. Conti, A. Majerus, V. Di Noto, C. Korte, W. Lehnert, D Stolten, Phys. Chem. Chem. Phys. 14, 10022-10026 (2012) [2] F. Conti, S. Willbold, S. Mammi, C. Korte, W. Lehnert, D. Stolten, New J. Chem. 37, 152-156 (2013). [3] A. Majerus, F. Conti, C. Korte, W. Lehnert, D. Stolten, ECS Transaction, in press. [4] G. A. Giffin, F. Conti, S. Lavina, A. Majerus, G. Pace, C. Korte, W. Lehnert, V. Di Noto, Int. J. Hydrogen Energy, submitted
- …
