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排序方式: 共有619条查询结果,搜索用时 15 毫秒
611.
In the acetylation of an oxygenated calix[4]arene homologue in the presence of CsF as a base, relaxation of the reaction system to the equilibrium composition takes place through several intra- and intermolecular steps that can be easily controlled to obtain the various acetyl derivatives. The effect of different bases is also discussed. 相似文献
612.
Summary: The influence of the crystalline structure on the pollutant sorption properties of high porosity syndiotactic polystyrene (sPS) aerogels has been made visible by using azulene, a blue dye, capable to form a clathrate phase with sPS. The bluish coloration observed for aerogels with the nanoporous δ-form and the absence of coloration for aerogels with the densely-packed γ-form clearly establish that the crystalline nanopores play a key role for the removal of pollutant traces from water or air. 相似文献
613.
The notion of ideal convergence is a generalization of statistical convergence which has been intensively investigated in last few years.For an admissible ideal ∮N× N,the aim of the present paper is to introduce the concepts of ∮-convergence and ∮*-convergence for double sequences on probabilistic normed spaces(PN spaces for short).We give some relations related to these notions and find condition on the ideal ∮ for which both the notions coincide.We also define ∮-Cauchy and ∮*-Cauchy double sequences on PN spaces and show that ∮-convergent double sequences are ∮-Cauchy on these spaces.We establish example which shows that our method of convergence for double sequences on PN spaces is more general. 相似文献
614.
Arminas Urbonavi
ius Graziana Fortunato Emilija Ambrazaityt Elena Plytninkien Aurimas Bieliauskas Vaida Miliinait Renzo Luisi Egl Arba
iauskien Sonata Kriktolaityt Algirdas a
kus 《Molecules (Basel, Switzerland)》2022,27(12)
An efficient synthetic route to construct diverse pyrazole-based chalcones from 1-phenyl-1H-pyrazol-3-ols bearing a formyl or acetyl group on the C4 position of pyrazole ring, employing a base-catalysed Claisen–Schmidt condensation reaction, is described. Isomeric chalcones were further reacted with N-hydroxy-4-toluenesulfonamide and regioselective formation of 3,5-disubstituted 1,2-oxazoles was established. The novel pyrazole-chalcones and 1,2-oxazoles were characterized by an in-depth analysis of NMR spectral data, which were obtained through a combination of standard and advanced NMR spectroscopy techniques. 相似文献
615.
Lidiani Figueiredo Santana Bruna Larissa Spontoni do Espirito Santo Mariana Bento Tatara Fbio Juliano Negro Júlio Croda Flvio Macedo Alves Wander Fernando de Oliveira Filiú Leandro Fontoura Cavalheiro Carlos Eduardo Domingues Nazrio Marcel Arakaki Asato Bernardo Bacelar de Faria Valter Arago do Nascimento Rita de Cssia Avellaneda Guimares Karine de Cssia Freitas Priscila Aiko Hiane 《Molecules (Basel, Switzerland)》2022,27(19)
Background: Studies indicate that different parts of Carica papaya Linn have nutritional properties that mean it can be used as an adjuvant for the treatment of various pathologies. Methods: The fatty acid composition of the oil extracted from the seeds of Carica papaya Linn was evaluated by gas chromatography, and an acute toxicity test was performed. For the experiment, Swiss mice were fed a balanced or high-fat diet and supplemented with saline, soybean oil, olive oil, or papaya seed oil. Oral glucose tolerance and insulin sensitivity tests were performed. After euthanasia, adiposity, glycemia, total cholesterol and fractions, insulin, resistin, leptin, MCP-1, TNF-α, and IL-6 and the histology of the liver, pancreas, and adipose tissue were evaluated. Results: Papaya seed oil showed predominance of monounsaturated fatty acids in its composition. No changes were observed in the acute toxicity test. Had lower food intake in grams, and caloric intake and in the area of adipocytes without minimizing weight gain or adiposity and impacting the liver or pancreas. Reductions in total and non-HDL-c, LDL-c, and VLDL-c were also observed. The treatment had a hypoglycemic and protective effect on insulin resistance. Supplementation also resulted in higher leptin and lower insulin and cytokine resistance. Conclusions: Under these experimental conditions, papaya seed oil led to higher amounts of monounsaturated fatty acids and had hypocholesterolemic, hypotriglyceridemic, and hypoglycemic effects. 相似文献
616.
Graciliana Lopes Elisabete Gomes Mariana Barbosa Joo Bernardo Patrícia Valento 《Molecules (Basel, Switzerland)》2022,27(22)
Background: The use of plants for therapeutic purposes has been supported by growing scientific evidence. Methods: This work consisted of (i) characterizing the phenolic compounds present in both aqueous and hydroethanol (1:1, v/v) extracts of camel grass, by hyphenated liquid chromatographic techniques, (ii) evaluating their anti-inflammatory, antioxidant, and neuromodulation potential, through in vitro cell and cell-free models, and (iii) establishing a relationship between the chemical profiles of the extracts and their biological activities. Results: Several caffeic acid and flavonoid derivatives were determined in both extracts. The extracts displayed scavenging capacity against the physiologically relevant nitric oxide (•NO) and superoxide anion (O2•−) radicals, significantly reduced NO production in lipopolysaccharide (LPS)-stimulated macrophages (RAW 264.7), and inhibited the activity of hyaluronidase (HAase), acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). Some of these bioactivities were found to be related with the chemical profile of the extracts, namely with 3-caffeoylquinic, 4-caffeoylquinic, chlorogenic, and p-coumaric acids, as well as with luteolin and apigenin derivatives. Conclusions: This study reports, for the first time, the potential medicinal properties of aqueous and hydroethanol extracts of camel grass in the RAW 264.7 cell model of inflammation, and in neurologically related conditions. 相似文献
617.
Victoria Mae Tsuruzaki Shinkai Izana Marize Oliveira Sampaio Eline Gomes dos Santos Adan Jesús Galu-Parra Dionisia Pelaes Ferreira Drielly Dayanne Monteiro Santos Baliza Neidiane Farias Ramos Raphael Sanzio Pimenta Rommel Mario Rodriguez Burbano Chubert Bernardo Castro Sena Barbarella Matos Macchi Irlon Maciel Ferreira Edilene Oliveira Silva Jos Luiz Martins do Nascimento 《Molecules (Basel, Switzerland)》2022,27(24)
618.
Olivo-Alanís Daniel Atilano-Camino Marina Montserrat García-González Alcione Humberto-Álvarez Luis García-Reyes Refugio Bernardo 《Journal of Sol-Gel Science and Technology》2021,100(3):538-554
Journal of Sol-Gel Science and Technology - A novel method was proposed to incorporate chlorophyll molecules into the phenolic resins for the photocatalytic degradation of methylene blue and... 相似文献
619.
Francesco Ciardelli Angelina Altomare Giuseppe Conti Guillermo Arribas Bernardo Mendez Alida Ismayel 《Macromolecular Symposia》1994,80(1):29-44
Macromolecular ligands have been widely used in the past two decades with the objective of preparing structurally defined heterogeneous catalysts from soluble organometallic complexes. This activity has been largely reconsidered and focused on few specific systems. In this connection the present paper reviews recent data concerning the preparation of macromolecular metal complexes derived from transition metals which can produce active catalytic complexes for olefin polymerization and oligomerization and comparison is made about the suitability of both organic resins (crosslinked polystyrene) and inorganic materials (silica, alumina and zeolites). 相似文献