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1.
Vladimir Fal’ko Andre Geim Sankar Das Sarma Allan MacDonald Philip Kim 《Solid State Communications》2009,149(27-28):1039-1040
2.
The avocado peel is an agro-industrial by-product that has exhibited a massive increase in its production in the last few years. The reuse and valorisation of this by-product are essential since its disposal raises environmental concerns. In the present study, ethanolic extracts of avocado peels of the Hass variety were obtained, for three extraction times (1.5 h, 3 h and 4 h) and analysed for their antioxidant and antibacterial properties. Antioxidant evaluations of the extracts revealed that the extraction time of 1.5 h exhibited the best results amongst the three, with a DPPH inhibition percentage of 93.92 ± 1.29 and an IC50 percentage, the necessary concentration of the extract to inhibit 50% of DPPH, of 37.30 ± 1.00. The antibacterial capacity of the extracts was evaluated and it was revealed that they were able to inhibit the growth and development of bacteria of the Staphylococcus family. The obtained extract was incorporated in two types of cosmetic formulations (oil-in-water and water-in-oil) and their stability was evaluated and compared with formulations containing synthetic preservatives (BHT and phenoxyethanol). The results of the stability evaluation suggest that the avocado peel extract has the potential to be incorporated in both types of emulsions, acting as an antioxidant and antibacterial agent, proving it to be a viable option to reduce/replace the use of synthetic preservatives. Furthermore, the avocado peel extract proved to be more effective and stable in oil-in-water emulsions. These results highlight the possibility of obtaining sustainable cosmetics, significantly reducing the negative impacts on the environment by the incorporation of extracts sourced from the avocado peel, an interesting source of phenolic compounds, an abundant and low-cost by-product. 相似文献
3.
[structure: see text] Sterically hindered tetraaminomethylated resorcarenes form inclusion complexes in CDCl(3) with acetonitrile and acetaldehyde, which are kinetically stable on the NMR time scale at 233 K. 相似文献
4.
N. I. Solin V. A. Kazantsev L. D. Fal’kovskaya S. V. Naumov 《Physics of the Solid State》2005,47(10):1900-1908
Variations in the thermopower, electrical resistivity, magnetoresistance, thermal expansion coefficients, and their anisotropy with temperature were detected near room temperature in single crystals of weakly doped lanthanum manganites La1?xAxMnO3 (A = Ca, Sr; x = 0.07–0.125) with orthorhombic structure. The results obtained are discussed in terms of a model of phase separation related to polaron anisotropy. Due to a gain in exchange and elastic energies in the lattice, small-radius magnetic polarons can merge to form polarons of a larger size, which would contain now not one but rather a few electrons (equal in number to the polarons in the cluster). As a result, short-range order in a cluster and phase separation set in at a temperature Tps ≈ 250–300 K, which is approximately equal to the Curie temperature TC of conducting manganites with x ≈ 0.2–0.3. 相似文献
5.
W.?Barszczewska J.?Kopyra J.?Wnorowska I.?SzamrejEmail author N. L.?Asfandiarov S. A.?Pshenichnyuk S. A.?Fal’ko 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2005,35(2):323-326
Thermal electron attachment rate constants for CH2ClCHBrCH3 and
CH2ClCH2CH2Br have been measured using electron swarm method.
Corresponding rate constants are equal to 3.5×10-10 and
2.5×10-10 cm3 molec-1 s-1, respectively. Parallely,
negative ion mass spectra of these compounds as well as CH2FCH2Br,
CH2ClCH2Br, CH2BrCH2Br and CF3CHClBr has been
measured with negative ion mass spectrometry method. The rate constants have
been compared with the negative ion mass spectra. 相似文献
6.
Joseph Aswathy Fal Jacek Żyła Gaweł Mathew Suresh 《Journal of Thermal Analysis and Calorimetry》2019,135(2):1373-1380
Journal of Thermal Analysis and Calorimetry - Understanding the behavior of ionic liquids (ILs) in ionic liquid-based nanofluids has great significance for its proper application. The phase changes... 相似文献
7.
The concept of an extended Brillouin zone is used to analyze the intensity of phonon modes observed in optical and Raman investigations
of different polytypes of silicon carbide. It is shown that the relative intensity of these modes agrees with the magnitude
of the splitting of the doublets, which are degenerate in the extended zone.
Pis’ma Zh. éksp. Teor. Fiz. 69, No. 3, 247–250 (10 February 1999) 相似文献
8.
The influence of a potential barrier on the transition radiation in the form of volume and surface electromagnetic waves emitted
by a charged particle crossing an interface between media is investigated. It is shown that the volume-wave radiation field
arises not only as a result of the jump in the dielectric constant at the boundary but also as a result of the velocity jump
and the reflection of an electron induced by the presence of a nonuniform potential barrier. The angular distribution of the
transition radiation intensity is obtained.
Zh. Tekh. Fiz. 68, 11–14 (January 1998) 相似文献
9.
M. N. Zizin S. N. Zizina L. V. Kryakvin V. A. Pitilimov V. A. Tereshonok 《Physics of Atomic Nuclei》2011,74(14):1908-1911
The effectiveness of the VVER-1000 reactor scram system is analyzed using ionization chamber currents with different sets
of kinetic parameters with allowance for the isotopic composition in the calculation of these parameters. The most “correct,
aesthetically acceptable” results are obtained using the eight-group constants of the ROSFOND (BNAB-RF) library. The difference
between the maximum and minimum values of the scram system effectiveness calculated with different sets of kinetic parameters
slightly exceeds 2β. The problems of introducing corrections due to spatial effects are not considered in this study. 相似文献
10.
M. A. Ivanov V. Ya. Mitrofanov L. D. Fal’kovskaya A. Ya. Fishman B. S. Tsukerblat 《JETP Letters》2005,81(1):15-18
The possibility of a considerable increase in NMR intensity has been shown for absorption on mixed-valence 3d ions in magnetically ordered crystals. This effect is determined by the high intensity of electric dipole transitions between the ground and low excited levels of a mixed-valence complex, as well as by the existence of the unfrozen orbital angular momentum in such complexes, which mixes nuclear and electron states. 相似文献