Search results for "bridge"
showing 10 items of 355 documents
Concrete arch bridges erected by suspended cantilever method vs cable–stayed bridges
2011
Fenomeni lenti nelle fasi di costruzione ed esercizio degli impalcati da ponte precompressi
2010
Creep effects and stress adjustments in cable-stayed bridges with concrete deck
2010
In construction stages of cable-stayed bridges with prestressed concrete deck, the influence of creep on stresses and strains is very important in order to foresee the final patterns of internal forces and displacements. In cantilever construction, the concrete deck can be considered, in each stage, as a continuous beam resting on elastic restraints, which modify with successive additions of new segments, until the last one has been assembled. In these stages stress relaxation in concrete occurs as well as vertical displacements increase. Ehen structure has been closed by inserting midspan segment, stress redistribution begins, due to creep. Deformation and internal force development in con…
A stress ribbon footbridge as the tie of an arch bridge.
2008
Dispositions légales concernant les ponts dans la législation de Justinien
2019
Many bridges built in the ancient Rome have survived to the present time. In this presentation, the author does not focus his attention on the architectural, archaeological, construction or statistical aspects. He discusses, above all, the legal regulations concerning the bridges in the Justinian's legislation. He is looking for an answer to the question of who in the ancient times at the Romans’ supervised the bridges. He wonders if the curatores pontis existed? It touches on the question of building a "private" bridge, the correlation of bridge issues and servitude, the bridge versus assassination, the bridge versus a suicide or the bridge versus taxes paid by the Church. The Romans did n…
Overview and experimental analysis of MC SPWM techniques for single-phase five level cascaded H-bridge FPGA controller-based
2016
This paper presents an overview and experimental analysis of the MC SPWM techniques for single-phase cascaded H-bridge inverter. The multilevel power converters are an alternative to traditional converters known as “three-level converters”. The voltage waveforms and the related frequency spectra, which have been obtained by simulation analysis in Matlab-Simulink environment, are here reported for all the proposed modulation techniques. The simulation results have been experimentally validated through means of a DC/AC, five-level, single-phase converter prototype with an appropriate test bench.
WITTA Between Globalization and Localization: New Challenges in View of Geopolitical Developments, Impending Digitalization, and Artificial Intellige…
2020
Internationalization of higher education also concerns the training of translators, interpreters, and other language service providers. Their services will continue to be of paramount importance for global development, where they become increasingly important as a bridge for economic and cultural exchanges. The Belt and Road Initiative of China will strengthen the demand for language services in an increasingly transnational environment. Since new forms of cooperation are necessary and desirable, WITTA as a new association should strive at becoming an autonomous transnational Think Tank that generates policy-oriented research, analysis, and advice on domestic and international issues in the…
Alternating Ferro/Antiferromagnetic Copper(II) Chain Containing an Unprecedented Triple Formato/Hydroxido/Sulfato Bridge.
2016
The first example of a triple formato/hydroxido/sulfato (FHS) bridge for any metal is reported in compound [Cu2(bpym)(OH)(HCO2)(SO4)(H2O)2]·3H2O (1). Its structure shows the presence of alternating triple FHS bridges and 2,2'-bipyrimidine (bpym) ones. Although in the initial synthesis the sulfate anions were introduced accidentally, here we report the rational synthesis and the magnetic properties of this compound. The magnetic properties show that 1 is an alternating ferro/antiferromagnetic (F/AF) chain compound with predominant antiferromagnetic interactions and were fit to an alternating F/AF S = (1)/2 chain with g = 2.103, JAF = -139 cm(-1), and JF = 116 cm(-1) (α = JF/|JAF| = 0.83). Th…
Group 13 complexes of dipyridylmethane, a forgotten ligand in coordination chemistry.
2015
The reactions of dipyridylmethane (dpma) with group 13 trichlorides were investigated in 1 : 1 and 1 : 2 molar ratios using NMR spectroscopy and X-ray crystallography. With 1 : 1 stoichiometry and Et2O as solvent, reactions employing AlCl3 or GaCl3 gave mixtures of products with the salt [(dpma)2MCl2](+)[MCl4](-) (M = Al, Ga) as the main species. The corresponding reactions in 1 : 2 molar ratio gave similar mixtures but with [(dpma)MCl2](+)[MCl4](-) as the primary product. Pure salts [(dpma)AlCl2](+)[Cl](-) and [(dpma)AlCl2](+)[AlCl4](-) could be obtained by performing the reactions in CH3CN. In the case of InCl3, a neutral monoadduct (dpma)InCl3 formed regardless of the stoichiometry emplo…
Synthesis of Optically Active 15-epi-9,14-Methylene Lipoxin A4
2018
The synthesis of lipoxin A4 and B4 analogues (LXA4, LXB4) to gain access to stabilized inflammation resolving compounds is an important field of research. Starting from known structural requirements of the natural compounds displaying biological activity and a broad investigation of their rapid metabolism, various LXA4 derivatives have been developed and tested. Focusing on variation and stabilization of the conjugated E,E,Z,E C7–C14 tetraene moiety of natural LXA4, a methylene bridge introduced between C9 and C14 might suppress any Z/E isomerization of the C11–C12 olefin. Intending to enable at least known structure variations in connection with the C1–C7 and the C15–C20 fragments, a conve…