Results 51 to 60 of about 16,231 (179)

Triterpenes from Protium Hebetatum Resin [PDF]

Natural Product Communications, 2010
Three olean (β-amyrenone, β-amyrin and maniladiol), three ursane (α-amyrinone, α-amyrin and breine) and four tirucallane (3-oxotirucalla-8,24-dien-21-óic acid, 3α-hydroxytirucalla-8,24-dien-21-oic acid, 3α-acetoxytirucalla-8,24-dien-21-oic acid and 3α-hydroxytirucalla-7,24-dien-21-oic acid) triterpenes were isolated from the oleoresin of Protium ...
Delcio Dias, Marques, Ilmar Bernardo, Graebner, Telma Leda Gomes, de Lemos, Luciana Lucas, Machado, Jõao Carlos Costa, Assunção, Francisco José Queiroz, Monte   +5 more
openaire   +2 more sources

Stability and hyperfine structure of the four- and five-body muon-atomic clusters $a^{+} b^{+} \mu^{-} e^{-}$ and $a^{+} b^{+} \mu^{-} e^{-} e^{-}$

, 2012
Based on the results of accurate variational calculations we demonstrate stability of the five-body negatively charged ions $a^{+} b^{+} \mu^{-} e^{-} e^{-}$. Each of these five-body ions contains two electrons $e^{-}$, one negatively charged muon $\mu^{-
A. M. Frolov, A.M. Frolov, A.M. Frolov, A.M. Frolov, D. M. Wardlaw, N.N. Kolesnikov   +5 more
core   +1 more source

Efeito de duas intensidades de colheita de madeira na estrutura de uma floresta natural na região de Paragominas, Pará. [PDF]

, 2013
Foram estudadas as mudanças na estrutura de 108ha de uma floresta primária submetida a duas intensidades de colheita de madeira, na Fazenda Rio Capim, pertencente à Cikel Brasil Verde Madeiras Ltda., no município de Paragominas, Pará.
CARVALHO, J. O. P. de, FRANCEZ, L. M. de B., JARDIM, F. C. da S., PINHEIRO, K. A. O., QUANZ, B.   +4 more
core   +1 more source

Process Simulation of a Temperature Swing Absorption Process for Hydrogen Isotope Separation

Energies
Temperature Swing Absorption (TSA) is the primary candidate for the Isotope Rebalancing and Protium Removal (IRPR) system within the envisioned EU-DEMO fusion reactor fuel cycle.
Annika Uihlein, Jonas Caspar Schwenzer, Stefan Hanke, Thomas Giegerich   +3 more
doaj   +1 more source

Metal Hydrides‐Based Hydrogen Purification Systems—A Review

MetalMat, Volume 3, Issue 1, March 2026.
Metal hydrides as an innovative means to purify hydrogen can enable new avenues in the use of hydrogen as a clean energy vector across its production methods. ABSTRACT This review investigates the critical role of purification for enabling the use of hydrogen from various production pathways.
Cameron Reid, Wei Liu, Kondo‐Francois Aguey‐Zinsou   +2 more
wiley   +1 more source

Temperature dependence of dynamic, tunnelling and kinetic isotope effects in formate dehydrogenase [PDF]

, 2018
The origin of the catalytic power of enzymes has been a question of debate for a long time. In this regard, the possible contribution of protein dynamics in enzymatic catalysis has become one of the most controversial topics.
Castillo, Raquel, Moliner, Vicent, Oliva, Mónica, Roca, Maite, Ruiz-Pernía, José Javier   +4 more
core   +2 more sources

Soil Properties and Plant Species Identity Independently Influence Arbuscular Mycorrhizal Fungal Composition Across Lowland Tropical Forests

Biotropica, Volume 58, Issue 2, March 2026.
We found that plant species identity and soil properties, especially soil phosphorus availability, independently structured arbuscular mycorrhizal fungal (AMF) community composition in tropical forests across central Panama. We also found that soil nutrient availability may mediate the interaction networks between plants and AMF. ABSTRACT Plant species
Mareli Sánchez‐Juliá, Blaine D. Martin, Iker R. Yturralde, Sunshine A. Van Bael   +3 more
wiley   +1 more source

Regularized estimation for highly multivariate log Gaussian Cox processes

, 2019
Statistical inference for highly multivariate point pattern data is challenging due to complex models with large numbers of parameters. In this paper, we develop numerically stable and efficient parameter estimation and model selection algorithms for a ...
Choiruddin, Achmad, Coeurjolly, Jean-François, Cuevas-Pacheco, Francisco, Waagepetersen, Rasmus   +3 more
core   +4 more sources

Phytosociological importance of an ombrophilous forest fragment in the State of Roraima, Brazil = Importância fitossociológica de um fragmento de floresta ombrófila densa no estado de Roraima, Brasil

Agro@mbiente On-line, 2016
The aim of this study was to characterise the phytosociology of a fragment of native forest in the town of Caroebe, in the State of Roraima, Brazil. All trees with a DBH ≥ 15 cm were inventoried in 18 permanent plots of 15 x 20 m (300 m²). There were 175
Luiz Fernandes Silva Dionisio, Osmar Serra Bonfim Filho, Bruno Roberto de Souza Crivelli, Jefferson Peixoto Gomes, Marcelo Henrique Silva de Oliveira, João Olegário Pereira de Carvalho   +5 more
doaj   +1 more source

Forest Reorganisation After Natural Disturbance: A Synthesis

Global Ecology and Biogeography, Volume 35, Issue 3, March 2026.
ABSTRACT Aim Natural disturbances are intensifying under global change, yet a global synthesis of their effects on forest structure and composition remains lacking. We aimed to assess the prevalence of structural versus compositional changes and to identify common post‐disturbance reorganisation pathways across forest biomes.
Judit Lecina‐Diaz, Monica G. Turner, Rupert Seidl   +2 more
wiley   +1 more source