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91.
A. J. Cavaleiro A. S. Ramos R. M. S. Martins C. Baetz M. T. Vieira F. M. Braz Fernandes 《Journal of Materials Engineering and Performance》2014,23(7):2446-2449
Joining shape-memory alloys (SMA) to other materials is strongly required in order to enlarge their fields of application. Fusion welding induces strong compositional and microstructural changes that significantly affect the shape-memory effect and the superelastic behavior of these alloys. The exothermic and in some cases self-propagating character of some nano-multilayer reactions is explored in this study as an alternative for joining SMA. To follow these very fast reactions, high brilliance sources, such as synchrotron radiation, are required. In situ high-resolution x-ray diffraction data, giving the phase evolution sequence with temperature of the Ni/Ti multilayer thin films under study, are presented. A correlation between the multilayer design and the tendency for the sequence of phase formation is established. 相似文献
92.
Water loss is a big challenge for water supply companies worldwide, and the Water Network Partitioning (WNP) is an excellent tool for water loss management–particularly in the current difficult economic and financial conditions. WNP is a recent research line and consists in dividing the water distribution network into smaller zones called District Metered Areas (DMAs) with one (or more, in exceptional cases) supply point, to reduce the network complexity and/or allow pressure management. Since there are several possible future scenarios, such as the water demand and/or the infrastructure degradation forecasts, which may have different impacts on the hydraulic behaviour, in this paper a computational application, based on an optimization model, is proposed to achieve a compromise between robustness required for the DMAs design (using a baseline scenario) and different decision makers’ options (using other scenarios with a lower “probability” of occurrence), to reduce the total cost. The objective function reflects the minimization of the squared deviations between the total cost of the DMAs design and the minimum cost for each scenario forecasted for the project plan, multiplied by the weight or “probability” of occurrence for each of the scenarios. The performance of the computational application is illustrated with a case study, and the results are encouraging. 相似文献
93.
Soraya Mendes de Souza Lineu Jose Pedroso Paulo Marcelo Vieira Ribeiro 《土木工程与建筑:英文版》2013,(9):1111-1117
Problems of fluid structure interactions are governed by a set of fundamental parameters. This work aims at showing through simple examples the changes in natural vibration frequencies and mode shapes for wall-cavity systems when the structural rigidity is modified. Numerical results are constructed using ANSYS software with triangular finite elements for both the fluid (2D acoustic elements) and the solid (plane stress) domains. These former results are compared to proposed analytical expressions, showing an alternative benchmark tool for the analyst. Very rigid wall structures imply in frequencies and mode shapes almost identical to those achieved for an acoustic cavity with Neumann boundary condition at the interface. In this case, the wall behaves as rigid and fluid-structure system mode shapes are similar to those achieved for the uncoupled reservoir case. 相似文献
94.
This paper adopts two perspectives. The first is a framing process aimed at defining and examining the conditions for adopting adaptive coastal governance. The second applies to relevant themes of changing coastal policy, central to the testing of adaptive coastal governance, namely cooperative science, risk-sensitive planning, socially fair insurance cover and effective ways to design, finance and engage with local communities over actual coastal change. We illuminate both missions through case studies in North Norfolk (England) and Portugal, all notably affected by coastal change. In England and Portugal, there is a broad understanding and acceptance of the likely effects of climate change. This recognition encourages debates over risk-averse planning, the design of proactive insurance cover, creative relocation of endangered property and new ways of predicting and paying for coastal adjustment. Yet, moving from a basic willingness to engage with coastal change to actual practices of landscape adjustment through such policy shifts is proving very difficult. In this research, we find that coastal landscapes are lived experiences, resigned acceptances of inevitable change and hopeful imaginings. Coastal management institutions are not geared to resolving this incompatibility and this paper explains why. 相似文献
95.
Territorial development in the Cape Verde archipelago under the Estado Novo dictatorship (1953–1974)
Despite Portugal's neutrality in the Second World War (1939–1945), the subsequent new world order meant that the Portuguese Government felt obliged to revise its overseas policies. A new regional awareness could be seen in the Six-Year National Development Plans launched by Estado Novo from 1953 until the revolution of 1974. The territory and its strategic potential were emphasized in the context of national policies of overseas urbanization. Interventions in Cape Verde are visible particularly in the First Development Plan, which was based on equipping the province's public facilities. The methodology of intervention involved setting up missions aimed at planning a set of specific public works which were essential to the development of existing settlements. A sharp increase in the development of the territory through the work of specialized brigades took place in the Third Development Plan, when a set of public works on road, hydraulic and electricity networks was undertaken. The planning of infrastructures that was undertaken in these years was essential to the development of the archipelago and the resulting regional and urban land-use planning of the various islands. 相似文献
96.
Rayssa Ferreira Zanatta Tatiane Josefa da Silva Maria Filomena Rocha Lima Huhtala Alessandra Bühler Borges Carlos Rocha Gomes Torres 《Journal of Adhesion Science and Technology》2016,30(23):2557-2564
Purpose: The aim of this study was to evaluate the influence of previous application of an adhesive system on bond strength of resinous liner materials to dentin. Methods: Ninety bovine incisors crowns had a 6 × 6 mm area of dentin exposed, with minimum of 2 mm thickness. They were embedded in acrylic resin, and the dentin was polished with P600 SiC sandpaper for 30 s to standardize the smear layer. The specimens were divided into 6 groups (n = 15) according to the application or not of a self-etching system (Futurabond U – Voco) and the type of resinous liner used: A+Ionoseal (adhesive and Ionoseal – Voco); Ionoseal (Ionoseal only); A+Vitrebond (adhesive and Vitrebond – 3M/ESPE); Vitrebond (Vitrebond only); A+Ionosit (adhesive and Ionosit – DMG) and Ionosit (Ionosit only). Adhesives were used following manufacturer’s instructions, and the liner materials were applied inside a 2-mm-depth matrix and light-cured for 20 s. The bond strength was measured by microtensile test, using a universal testing machine with a cross-speed of 1 mm/min. Data were analyzed using one-way ANOVA and Tukey’s test (p < 0.05). Results: The adhesive system application increased bond strength of all liners tested. Ionoseal presented the highest bond strength when the adhesive system was used and exhibited similar performance to Vitrebond without adhesive. Ionosit without adhesive showed the smallest bond strength compared with the other liners tested. Conclusion: The application of an adhesive system prior to the use of the resinous liners improved the bond strength to dentin and should be preconized. 相似文献
97.
A Quinacrine Analogue Selective Against Gastric Cancer Cells: Insight from Biochemical and Biophysical Studies
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Ana Gomes Dr. Iva Fernandes Dr. Cátia Teixeira Prof. Nuno Mateus Prof. M. J. Sottomayor Prof. Paula Gomes 《ChemMedChem》2016,11(24):2703-2712
One of the earliest synthetic antimalarial drugs, quinacrine, was recently reported as interesting for the treatment of acute myeloid leukemia. Inspired by this and similar findings, we evaluated a set of quinacrine analogues against gastric (MKN‐28), colon (Caco‐2), and breast (MFC‐7) cancer cell lines and one normal human fibroblast cell line (HFF‐1). All the compounds, previously developed by us as dual‐stage antimalarial leads, displayed antiproliferative activity, and one of the set stood out as selective toward the gastric cancer cell line, MKN‐28. Interestingly, this compound was transported across an in vitro MKN‐28 model cell line in low amounts, and approximately 80 % was trapped inside those cells. Nuclear targeting of the same compound and its interactions with calf thymus DNA were assessed through combined fluorescence microscopy, spectroscopy, and calorimetry studies, which provided evidence for the compound's ability to reach the nucleus and to interact with DNA. 相似文献
98.
Inside Cover: Pro‐oxidant and Antioxidant Effects in Photodynamic Therapy: Cells Recognise that Not All Exogenous ROS Are Alike (ChemBioChem 9/2016)
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99.
Simões S. Ramos A. S. Viana F. Emadinia O. Vieira M. T. Vieira M. F. 《Journal of Materials Engineering and Performance》2016,25(10):4394-4401
Journal of Materials Engineering and Performance - Ni/Al multilayers are known to transform into NiAl in a highly exothermic and self-sustaining reaction. The fact that this reaction has a high... 相似文献
100.
Viviane Muniz da Silva Fragoso Carla Patrícia de Morais Coura Luanda Yanaan Hoppe Marília Amável Gomes Soares Dilson Silva Celia Martins Cortez 《International journal of molecular sciences》2016,17(1)
The aim of this work was to study the interaction of sulpiride with human serum albumin (HSA) and bovine serum albumin (BSA) through the fluorescence quenching technique. As sulpiride molecules emit fluorescence, we have developed a simple mathematical model to discriminate the quencher fluorescence from the albumin fluorescence in the solution where they interact. Sulpiride is an antipsychotic used in the treatment of several psychiatric disorders. We selectively excited the fluorescence of tryptophan residues with 290 nm wavelength and observed the quenching by titrating HSA and BSA solutions with sulpiride. Stern-Volmer graphs were plotted and quenching constants were estimated. Results showed that sulpiride form complexes with both albumins. Estimated association constants for the interaction sulpiride–HSA were 2.20 (±0.08) × 104 M−1, at 37 °C, and 5.46 (±0.20) × 104 M−1, at 25 °C. Those for the interaction sulpiride-BSA are 0.44 (±0.01) × 104 M−1, at 37 °C and 2.17 (±0.04) × 104 M−1, at 25 °C. The quenching intensity of BSA, which contains two tryptophan residues in the peptide chain, was found to be higher than that of HSA, what suggests that the primary binding site for sulpiride in albumin should be located next to the sub domain IB of the protein structure. 相似文献