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111.
Mediterranean Journal of Mathematics - We provide some invariance properties for a closed graph with respect to quasi-autonomous semilinear differential inclusion. As applications, we study a... 相似文献
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If \(\pi :E\rightarrow X\) is a locally trivial holomorphic fiber bundle, with positive dimensional connected fiber and with the total space E being a Stein manifold, and \(D\subset X\) is an arbitrary connected open subset, then there exists an open, connected Stein subset \(\widetilde{D}\subset E\) such that \(\pi (\widetilde{D})=D\). 相似文献
114.
Gabriela Niculae Nicoleta Badea Aurelia Meghea Ovidiu Oprea Ioana Lacatusu 《Photochemistry and photobiology》2013,89(5):1085-1094
The coencapsulation of two UV filters, butyl‐methoxydibenzoylmethane (BMDBM) and octocrylene (OCT), into lipid nanocarriers was explored to develop stable cosmetic formulations with broad‐spectrum photoprotection and slow release properties. Different types of nanocarriers in various concentrations of the two UV filters were tested to find the combination with the best absorption and release properties. Solid lipid nanoparticles (SLNs) and nanostructured lipid carriers (NLCs) have been the two types of lipid nanocarriers used. The NLCs were based on either medium chain triglycerides (MCT) or squalene (Sq). The following physicochemical properties of the nanocarriers have been evaluated: particle size, morphology, zeta potential (ZP), entrapment efficiency, loading capacity, and thermal behavior. The nanocarriers have been formulated into creams containing low amounts of UV filters (2.5% BMDBM and 1% OCT). The best photoprotection results were obtained with the cream based on NLCs prepared with MCT, having a sun protection factor (SPF) of 17.2 and an erythemal UVA protection factor (EUVA–PF) of 50.8. The photostability of the encapsulated BMDBM filter was confirmed by subjecting the nanocarriers‐based creams to in vitro irradiation. The prolonged UV‐protection efficacy was coupled with a slow in vitro release of the synthetic UV filters, which followed the Higuchi release model. 相似文献
115.
Ying Ma Dr. Yujing Ren Dr. Yanan Zhou Dr. Wei Liu Dr. Walid Baaziz Prof. Dr. Ovidiu Ersen Dr. Cuong Pham-Huu Dr. Mark Greiner Prof. Dr. Wei Chu Prof. Dr. Aiqin Wang Prof. Dr. Tao Zhang Prof. Dr. Yuefeng Liu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(48):21797-21803
Single-atom catalysts (SACs) have shown superior activity and/or selectivity for many energy- and environment-related reactions, but their stability at high site density and under reducing atmosphere remains unresolved. Herein, we elucidate the intrinsic driving force of a Pd single atom with high site density (up to 5 wt %) under reducing atmosphere, and its unique catalytic performance for hydrogenation reactions. In situ experiments and calculations reveal that Pd atoms tend to migrate into the surface vacancy-enriched MoC surface during the carburization process by transferring oxide crystals to carbide crystals, leading to the surface enrichment of atomic Pd instead of formation of particles. The Pd1/α-MoC catalyst exhibits high activity and excellent selectivity for liquid-phase hydrogenation of substituted nitroaromatics (>99 %) and gas-phase hydrogenation of CO2 to CO (>98 %). The Pd1/α-MoC catalyst could endure up to 400 °C without any observable aggregation of single atoms. 相似文献
116.
We establish new necessary and sufficient conditions for local invariance referring to semilinear differential inclusions,
conditions expressed in terms of a new suitable defined tangency concept. An application to the study of the Hamilton-Jacobi-Bellman
equation is given. 相似文献
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Alexandrina Nan Rodica Turcu Izabell Craciunescu Ovidiu Pana Holger Scharf Jürgen Liebscher 《Journal of polymer science. Part A, Polymer chemistry》2009,47(20):5397-5404
The graft polymerization of ε‐caprolactone (ε‐CL) onto magnetite was carried out under microwave irradiation in the presence of tin(II) 2‐ethylhexanoate. The molar ratio of ε‐CL to tin(II) 2‐ethylhexanoate was 300, whereas the molar ratio of ε‐CL to magnetite was 5. The chemical structures of the obtained poly(ε‐caprolactone) coated magnetic nanoparticles were characterized by FTIR and XPS spectroscopy. These magnetic‐polymer hybrid nanostructures were further investigated by X‐ray diffraction and magnetization measurements. The morphology of the magnetic core‐shell nanostructures were determined by TEM. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5397–5404, 2009 相似文献
119.
The present article applies the method of Geometric Analysis to the study H ‐type groups satisfying the J2 condition and finishes the series of works describing the Heisenberg group and the quaternion H ‐type group. The latter class of H ‐type groups satisfying the J2 condition is related to the octonions. The relations between the group structure and the boundary of the corresponding Siegel upper half space are given. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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