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941.
Lina Raudone Viktorija Puzeryt Gabriele Vilkickyte Aurelija Niekyte Juozas Lanauskas Jonas Viskelis Pranas Viskelis 《Molecules (Basel, Switzerland)》2021,26(16)
Sea buckthorn (Hippophae rhamnoides L. (HR)) leaf powders are the underutilized, promising resource of valuable compounds. Genotype and processing methods are key factors in the preparation of homogenous, stable, and quantified ingredients. The aim of this study was to evaluate the phenolic, triterpenic, antioxidant profiles, carotenoid and chlorophyll content, and chromatic characteristics of convection-dried and freeze-dried HR leaf powders obtained from ten different female cultivars, namely ‘Avgustinka’, ‘Botaniceskaja Liubitelskaja’, ‘Botaniceskaja’, ‘Hibrid Percika’, ‘Julia’, ‘Nivelena’, ‘Otradnaja’, ‘Podarok Sadu’, ‘Trofimovskaja’, and ‘Vorobjovskaja’. The chromatic characteristics were determined using the CIELAB scale. The phytochemical profiles were determined using HPLC-PDA (high performance liquid chromatography with photodiode array detector) analysis; spectrophotometric assays and antioxidant activities were investigated using ABTS (2,2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)) and FRAP (ferric ion reducing antioxidant power) assays. The sea buckthorn leaf powders had a yellowish-green appearance. The drying mode had a significant impact on the total antioxidant activity, chlorophyll content, and chromatic characteristics of the samples; the freeze-dried samples were superior in antioxidant activity, chlorophyll, carotenoid content, and chromatic profile, compared to convection-dried leaf powder samples. The determined triterpenic and phenolic profiles strongly depend on the cultivar, and the drying technique had no impact on qualitative and quantitative composition. Catechin, epigallocatechin, procyanidin B3, ursolic acid, α-amyrin, and β-sitosterol could be used as quantitative markers in the phenolic and triterpenic profiles. The cultivars ‘Avgustinka’, ‘Nivelena’, and ‘Botaniceskaja’ were superior to other tested cultivars, with the phytochemical composition and antioxidant activity. 相似文献
942.
D. Fischer D. Pospiech U. Scheler R. Navarro M. Messori P. Fabbri 《Macromolecular Symposia》2008,265(1):134-143
Summary: The sol-gel synthesis of organic-inorganic hybrids based on triethoxysilane- terminated poly(ethylene oxide) and tetraethylorthosilicate was monitored in-situ using three spectroscopic methods (FTIR/ATR, Raman, NIR). These spectroscopic methods allow in-situ monitoring of the evolution of hybrid materials starting from the modification of the polymer and the early steps of hydrolysis up to the network formation. By application of 29Si solid-state NMR spectroscopy the assignment and quantification of the Raman bands to different end groups and different cross-linking states was made. The sol-gel reaction was also followed by in-line NIR spectroscopy. A multivariate data analysis was accomplished to obtain a conversion-time curve. Furthermore, we investigated spin-coated films on wafers using FTIR transmission spectroscopy. 相似文献
943.
Annamalai Subashini Madhukar Hemamalini P. Thomas Muthiah Gabriele Bocelli Andrea Cantoni 《Journal of chemical crystallography》2009,39(2):112-116
Abstract The structure of the title compound (C17H15N3O4S)2 the schiff base, bis(N-(5-methyl-3-isoxazolyl)-4-[(2-hydroxy benzylidene)-amino]) benzene sulfonamide was elucidated by H1, C13 NMR, UV–VIS and IR spectroscopic techniques. The X-ray structure was determined in order to establish the conformation of
the molecule. The compound crystallizes in the triclinic space group P-1, with a = 11.419(1), b = 11.426(0), c = 13.316(1) ?, α = 71.94(2), β = 89.79(1), γ = 89.14(2)° and Z = 4. Two benzene rings and azomethine group are practically coplanar, as a result of intramolecular hydrogen bonds involving
the hydroxy O atom and azomethine N atom. The component species further interact via N–H···N and C–H···O hydrogen bonds and
π–π stacking interactions.
Index Abstract The title compound (C17H15N3O4S)2, Schiff base, bis(N-(5-methyl-3-isoxazolyl)-4-[(2-hydroxy benzylidene)-amino]) benzene sulfonamide was synthesized by the condensation of 4-amino-N-(5-methyl-3-isoxazolyl) benzene sulfonamide (SMZ) and 2-hydroxy benzaldehyde (SA). Its structure was confirmed by single
crystal X-ray diffraction analysis.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
944.
Belletti F Cotallo M Cruz A Fernandez LA Gordillo-Guerrero A Guidetti M Maiorano A Mantovani F Marinari E Martin-Mayor V Sudupe AM Navarro D Parisi G Perez-Gaviro S Ruiz-Lorenzo JJ Schifano SF Sciretti D Tarancon A Tripiccione R Velasco JL Yllanes D 《Physical review letters》2008,101(15):157201
We study numerically the nonequilibrium dynamics of the Ising spin glass, for a time spanning 11 orders of magnitude, thus approaching the experimentally relevant scale (i.e., seconds). We introduce novel analysis techniques to compute the coherence length in a model-independent way. We present strong evidence for a replicon correlator and for overlap equivalence. The emerging picture is compatible with noncoarsening behavior. 相似文献
945.
Gold vicinal surfaces (788), with a high density of steps, along with (111) flat surfaces taken as a reference, have been nanoindented and their resulting penetration curves and related defect structure comparatively analyzed by AFM and atomistic simulations. Stepped surfaces are shown to yield at smaller loads than (111) ones in agreement with calculations of the critical resolved shear stress needed to nucleate a dislocation. In the stepped surfaces, a novel intermediate state is identified in which the penetration curves depart from a Hertzian behavior prior to the appearance of pop-ins. This state is shown to result from heterogeneous nucleation at preexisting surface steps of dislocation loops, most of which retract and vanish when the indenter load is removed. 相似文献
946.
The car following model under discussion is a system of ordinary differential equations describing N cars moving around a circular road. We extend the stability analysis of the model in two directions: variable reaction time (depending on the headway) and an additional part describing the aggressive driving tendency. We study the global bifurcation dynamics and in particular its dependence on these two new ingredients. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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