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1.
Our empirical analysis focuses on the effect of regional policies on migration attraction factors in Europe. We employ a regression discontinuity design to assess the causal relationship between the reception of large amounts of public funds and migration flows in the EU-15 regions. In highly-subsidised regions, we find a large increase in the share of foreign citizens from less-developed countries when compared to low-subsidised regions with similar pre-treatment characteristics. The analysis shows that such an increase is due to the positive impact of the European regional policy on job market opportunities as well as the improvement of public goods supply. 相似文献
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A highly hydrophobic silica mesostructure was synthesized by a modification on the conventional co-condensation procedure that involved the partial substitution of hexadecytltrimethylammonium, used as mesostructure directing agent, by hexadecyltrimethoxysilane. That modification allowed the production of a highly ordered hexagonal silica mesostructure with the mesopores partially filled with high amounts of hexadecyl chains, covalently bonded to inorganic framework. After extracting the reminiscent template molecules, ibuprofen was loaded into the mesostructure in order to evaluate its drug release properties. The drug loading amount (21 wt%) was comparable to the one reported for MCM-41 with grafted propylamine groups (25 wt%), indicating that C16-chains were not fully compacted occluding the pores. A slow ibuprofen release was observed in simulated body fluid (pH 7.2) by a process controlled by an anomalous transport with contribution of diffusional and relaxational components, according to the Korsmeyer-Peppas kinetics model. That hydrophobic mesostructure produced has the potential of being use as a carrier for low water soluble drugs with an extended delivery effect, but without the disadvantages of co-releasing toxic surfactant molecules or the need of non-toxic specific templates to be prepared. 相似文献
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Roberta Bastos Vasques Marjory Moreira Levy Matheus Souza Rodrigues Francisco Wagner de Queiroz Almeida Neto Leonardo Paes da Silva Gustavo Leitão Vaz Álvaro Augusto Oliveira Magalhães Pedro de Lima-Neto Walney Silva Araújo 《工业材料与腐蚀》2021,72(8):1417-1432
Phosphate ester was investigated as a corrosion inhibitor for AISI 1018 carbon steel in carbon dioxide-saturated chloride solutions at different temperatures and pressures. The corrosion tests were realized by electrochemical techniques, weight loss measurements, bubble tests, and a high-pressure/high-temperature autoclave system. The corrosion tests demonstrated that the investigated molecule is an excellent corrosion inhibitor. The inhibiting effect is even bigger at high pressure and temperature than at atmospheric pressure and room temperature. The thermodynamic parameters were calculated and determined to obey the Langmuir isotherm. Polarization studies revealed that the evaluated inhibitor is a mixed type. 相似文献
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Lopez Daniel Andres Sanchez Chagas Luciana Gomes Batista Aline Domingues Guaita Maria Gabriella Detone Amorin Luís Henrique Cardozo da Silva Paulo Rogério Catarini Yamanishi Gustavo Zaia Dimas Augusto Morozin de Santana Henrique Urbano Alexandre 《Journal of Materials Science: Materials in Electronics》2021,32(13):17462-17472
Journal of Materials Science: Materials in Electronics - The increasing demand for lithium-ion batteries has stimulated the investigation of new compounds in order to reduce the costs and the... 相似文献
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Mobile Networks and Applications - Blockchain applications have continuously improved ever since its first debut on cryptocurrency. From then on, its uses have branched out from the financial... 相似文献
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da Silva Breno Augusto Tabosa Thome Pascoalino Liege Aguiar de Souza Ricardo Luiz Muniz Edvani Curti Curti Priscila Schroeder 《Polymer Bulletin》2020,77(3):1157-1176
Polymer Bulletin - In this work, electrospun fibers of poly(butylene adipate-co-terephthalate) (PBAT) and poly(N-isopropylacrylamide) (PNIPAAm) blends, PBAT/PNIPAAm, with different mass ratios,... 相似文献
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