177,800 research outputs found
Fruits of Sabia (Sabiaceae) from the Miocene of western North America and their biogeographic significance
No full textDistinctive, reticulately sculptured ellipsoidal endocarp impressions have been discovered in Middle Miocene lake deposits of Idaho and eastern Oregon in the northwestern USA. We describe a new species based on these endocarp impressions and compare them morphologically with previously described extinct and extant species of Sabia (Sabiaceae) using light microscopy and micro-CT scanning. Sabia megacarpa sp. nov. endocarps are distinguished by their large size but resemble other species of Sabia in their asymmetric elliptical shape, reticulate surface ribs, unilocular morphology and gland-dotted endocarp surface. Although Sabia is now native to Southeast Asia and Malesia, the fossil record indicates this genus was formerly present in Europe and North America. The new species indicates that Sabia survived until at least 16 million years ago in western North America
A new aporphine alkaloid from Sabia yunnanensis
No full textA new aporphine alkaloid, 1-hydroxy-2,3-dimethoxy-6-formyl-6a,7-dehydroaporphine, along with 15 known compounds have been isolated from the stems and leaves of Sabia yunnanensis. Their structures were established on the basis of spectral analysis
Two new pentacyclic triterpenes from Sabia parviflora
No full textTwo new pentacyclic triterpene acids, 1alpha 3beta-dihydroxyl-olean-12-en-28-oic acid and 1alpha, 2alpha, 3beta-trihydroxyl-olean-12-en-28-oic acid, were isolated from the arial parts of Sabia parviflora
Implementing a composite indicator approach for prioritizing activated sludge-based wastewater treatment plants at large spatial scale
No full textSuccessful implementation of the European Urban Wastewater Treatment Directive requires a deepened and multidisciplinary knowledge of the wastewater systems. The development of ready-to-use tools for decision makers is, in this sense, a challenge. This paper proposes a methodology to efficiently prioritize wastewater treatment plants (WWTPs) on the basis of the relative environmental, social and public health impacts, taking into account the territorial context issues. The proposed methodology has led to the implementation of a composite indicator. The several choices made for its development, from the definition of framework to the final outcomes, have been evaluated in depth and are supported through methodological and statistical techniques. The potential use of the composite indicator with the inherent advantages and limitations are discussed in order to provide a ready-to-use tool for final users for WWTPs prioritization. Moreover, a concise methodology for composite index implementation is described. © 2016 Elsevier Lt
Dynamic behavior of clobazam on high-performance liquid chromatography chiral stationary phases
No full textClobazam, a 1,5-benzodiazepin-2,4-dione, is a chiral molecule because its ground state conformation features a nonplanar seven-membered ring lacking reflection symmetry elements. The two conformational enantiomers of clobazam interconvert at room temperature by a simple ring-flipping process. Variable temperature HPLC on the Pirkle type (R)-N-(3,5-dinitronenzoyl)phenylglycine and (R,R)-Whelk-O1 chiral stationary phases (CSPs) allowed us to separate for the first time the conformational enantiomers of clobazam and to observe peak coalescence-decoalescence phenomena due to concomitant separation and interconversion processes occurring on the same time scale. Clobazam showed temperature dependent dynamic high-performance liquid chromatography (HPLC) profiles with interconversion plateaus on the two CSPs indicative of on-column enantiomer interconversion. (enantiomerization) in the column temperature range between Tcol = 10°C and Tcol = 30°C, whereas on-column interconversion was absent at temperature close to or lower than Tcol = 5°C. Computer simulation of exchange-deformed HPLC profiles using a program based on the stochastic model yielded the apparent rate constants for the on-column enantiomerization and the corresponding free energy activation barriers. At Tcol = 20°C the averaged enantiomerization barriers, ΔG(‡) , for clobazam were found in the range 21.08-21.53 kcal mol(-1) on the two CSPs. The experimental dynamic chromatograms and the corresponding interconversion barriers reported in this article are consistent with the literature data measured by DNMR at higher temperatures and in different solvents
Sabian, a novel flavonoid from Sabia yunnanensis
No full textA novel flavonoid, [2-(3,4-dihydroxy-phenyl)-3,5,7-trihydroxy-4-oxo-4 H -chromen-8-yl]-[8-hydroxy-7-( E -4-hydroxy-3-methyl-but-2-enyl)-2,2-dimethyl-chroman-5-yl]-acetic acid methyl ester (10), trivially named sabian, along with 11 known compounds, have been isolated from the stems and leaves of Sabia yunnanensis . Their structures were established on the basis of spectral analysis
Optimal post-combustion conditions for the purification of CO₂-rich exhaust streams from non-condensable reactive species
No full textAbstract not availableM. de Joannon, A. Chinnici, P. Sabia, R. Ragucc
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