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91.
Andrs Seoane Cezar Comanescu Noelia Casanova Rebeca García‐Fandio Xabier Diz Jos L. Mascareas Moiss Gulías 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(6):1714-1718
o‐Alkenyl N‐triflylanilides underwent rhodium(III)‐catalyzed oxidative annulations with alkynes to produce different types of naphthylamides in a process which involves the cleavage of two C?H bonds. Remarkably, besides formal dehydrogenative (4C+2C) cycloadducts, the reaction also produces variable amounts of isomeric naphthylamides, whose formation requires a formal migration of the alkenyl moiety from the ortho to the meta position of the anilide. The annulation reaction can be efficiently carried out in the absence of external oxidants, such as Cu(OAc)2. 相似文献
92.
Abad A Agulló C Cuñat AC de Alfonso I Navarro I Vera N 《Molecules (Basel, Switzerland)》2004,9(5):287-299
The commercially available monoterpene carvone has been efficiently converted into the tricyclo[3.2.1.0(2.7)]octane and bicyclo[3.2.1]octane systems characteristic of some biologically active compounds. The sequence used for this transformation involves as key features an intramolecular Diels-Alder reaction of a 5-vinyl-1,3-cyclohexadiene and a cyclopropane ring opening. 相似文献
93.
Vera Mara L. Palacios Camilo J. O. Daz Nieto Csar H. Palacios Noelia A. Di Carlantonio Natalia Luna Franco G. Torres Walter R. Flexer Victoria 《Journal of Solid State Electrochemistry》2022,26(9):1981-1994
Journal of Solid State Electrochemistry - It is expected that lithium sourcing from aqueous sources in the medium term will account for over half of worldwide production, since reserves in brines... 相似文献
94.
The suitability of coacervates for the preservation of organic pollutants after their extraction from water samples was investigated for the first time. Acid-induced sodium dodecanesulfonic acid (SDSA) micelle-based coacervates were selected for this purpose. Their capacity to preserve benzalkonium homologue (C12, C14 and C16) surfactants (BASs) and different polycyclic aromatic hydrocarbons (PAHs) [benzo(a)pyrene (BaP), benzo(b)fluoranthene (BbF), benzo(k)fluoranthene (BkF), benzo(ghi)perylene (BghiP), benzo(a)anthracene (BaA) and indene(1,2,3-c-d)pyrene (IP)] was investigated. BASs and PAHs were efficiently extracted by the coacervate by formation of mixed aggregates and hydrophobic interactions, respectively. Their stability into the coacervate was investigated under three temperature conditions (room temperature, 4 °C and −20 °C) and two hydrochloric acid concentrations (3.75 M and 4.2 M), which was used to induce coacervation. No losses were observed during at least 3 months at the different experimental conditions tested. The increase of the temperature up to 35 °C for a month did not affect the stability of the target compounds. No influence of the water matrix (distilled, river or wastewater) on the stabilization of BASs and PAHs was observed. The high-stabilizing capacity of the coacervate for the target compounds and its low volume make easy the transport and storage of analytes. 相似文献
95.
Patricia Reboredo-Rodríguez Carmen Gonzlez-Barreiro Elena Martínez-Carballo Noelia Cambeiro-Prez Raquel Rial-Otero María Figueiredo-Gonzlez Beatriz Cancho-Grande 《Molecules (Basel, Switzerland)》2021,26(21)
The Mediterranean diet includes virgin olive oil (VOO) as the main fat and olives as snacks. In addition to providing nutritional and organoleptic properties, VOO and the fruits (olives) contain an extensive number of bioactive compounds, mainly phenolic compounds, which are considered to be powerful antioxidants. Furthermore, olive byproducts, such as olive leaves, olive pomace, and olive mill wastewater, considered also as rich sources of phenolic compounds, are now valorized due to being mainly applied in the pharmaceutical and nutraceutical industries. The digestive system must physically and chemically break down these ingested olive-related products to release their phenolic compounds, which will be further metabolized to be used by the human organism. The first purpose of this review is to provide an overview of the current status of in-vitro static digestion models for olive-related products. In this sense, the in-vitro gastrointestinal digestion methods are widely used with the following aims: (i) to study how phenolic compounds are released from their matrices and to identify structural changes of phenolic compounds after the digestion of olive fruits and oils and (ii) to support the functional value of olive leaves and byproducts generated in the olive industry by assessing their health properties before and after the gastrointestinal process. The second purpose of this review is to survey and discuss all the results available to date. 相似文献
96.
97.
Elena Gómez Noelia Calvar Eugénia A. Macedo Ángeles Domínguez 《The Journal of chemical thermodynamics》2012,45(1):9-15
In this paper, physical properties of a high purity sample of the ionic liquid 1-propyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, [PMim][NTf2], and its binary mixtures with methanol, ethanol, 1-propanol, and 2-propanol were measured at atmospheric pressure. The temperature dependence of density, refractive index and speed of sound (293.15 to 343.15) K and dynamic viscosity (298.15 to 343.15) K were studied at atmospheric pressure by conventional techniques for the pure ionic liquid. For its mixtures with alcohols, density, speed of sound, and refractive index were measured at T = 298.15 K over the whole composition range. The thermal expansion coefficient of the [PMim][NTf2] was calculated from the experimental results using an empirical equation, and values of the excess molar volume, excess refractive index, and excess molar isentropic compressibility for the binary systems at the above mentioned temperature, were calculated and fitted to the Redlich–Kister equation. The heat capacity of the pure ionic liquid at T = 298.15 K was determined using DSC. 相似文献
98.
N Araújo SF Jenkinson RF Martínez AF Glawar MR Wormald TD Butters S Nakagawa I Adachi A Kato A Yoshihara K Akimitsu K Izumori GW Fleet 《Organic letters》2012,14(16):4174-4177
Ring closure of a 3,5-di-O-triflate derived from d-altrose with benzylamine allowed the formation of both monocyclic and bicyclic azetidine analogues of swainsonine. 相似文献
99.
This study focuses on a method for simultaneously determining personal care products in a wide range of polarities in different water matrices. The method is based on stir‐bar sorptive extraction followed by thermal desorption‐gas chromatography‐mass spectrometry. Prior to extraction, the parabens were acetylated to improve their affinity for the polydimethylsiloxane phase of the stir bar. The method showed good linearity, repeatability and reproducibility between days for all compounds and limits of detection at low ng/L levels (between 0.02 and 0.3 ng/L). The proposed method is also environmentally friendly, because it does not use organic solvents, and reduces the risk of external pollution, due to the minimal manipulation of the sample required. The method developed was successfully applied for the analysis of personal care products in different kinds of water matrices: influents and effluents of urban and industrial wastewater treatment plants, effluents of a reverse osmosis treatment plant and river waters. The influents of urban treatment plants generally showed the highest values for synthetic musks, with concentrations of up to 2219 ng/L of galaxolide, whereas the highest concentrations of parabens were detected in the industrial treatment plants influents. 相似文献
100.
Sebastián R Calvin V Mendoza N Pérez-Pé R García D Carreras C Cebrián-Pérez JA Muiño-Blanco T 《Journal of separation science》2012,35(10-11):1388-1398
The current methods of isolation of adipose tissue-derived stem cells result in a heterogeneous population that might interfere with their differentiation potential and makes it difficult to compare the results between different groups. Partition in aqueous two-phase systems is one of the few techniques that separate cells on the basis of surface properties, gentle enough to isolate fragile cell types in isotonic conditions without altering their structure, and can be easily scaled. In this study, stem cells isolated from human adipose tissue seeded and expanded in vitro were fractionated by using centrifugal countercurrent distribution in an aqueous two-phase system. The separated subpopulations revealed the high heterogeneity of adipose tissue-derived stem cell samples. Comparative partition analyses showed that aging induces a loss of heterogeneity, which is not due to a loss of cell viability associated to age. The phosphatidylserine externalization, an apoptotic feature, is the main factor in cell partition that results in a decreased hydrophobicity of the cell surface. This procedure may be suitable for separating adipose tissue-derived stem cell populations enriched in some functional and/or structural surface characteristics. The possibility of a very effective separation of different subpopulations in opposite phases would be an interesting development of the method. 相似文献