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Applicability study of a low cost seismic isolator prototype using recycled rubber

In order to protect buildings against earthquakes that are categorized as "common" according to the Peruvian Earthquake Resistant Standard, a prototype of Recycled Rubber Seismic Isolator ("RRSI") was developed in the structural laboratory of the Japan-Peru Center for Earthquake Engineering Research and Disaster Mitigation - CISMID, Peru. The raw material used to manufacture this device was recycled rubber tires; the rubber tire was cut into square shape sheets with 190mmx190mm of cross-section and a total thickness of around 11 mm. Rubber tire sheets were joined to each other by a vulcanization process, including rubber layers with 3mm of thickness made of recycled rubber tire powder in between rubber tire sheets; and in between the rubber tire sheet and the steel plate at both ends of the bearing.
 Two specimens were tested in a shaking table under a free vibration impulse or displacement in order to get their natural vibration frequency, natural period, and inherent damping. Then, to obtain the hysteretical behavior, a cyclic lateral reversal-loading test was conducted on three different specimens applying a constant axial load of 330MPa, 270MPa, and 220MPa respectively and a lateral displacement pattern with different levels of shear deformations up to the failure, which occurs at a shear strain of around 100%.
 From the experimental results, a nonlinear hysteretic behavior and energy dissipation were observed, decoupling the lateral movement. Finally, a numerical model was proposed to model the nonlinear hysteretic behavior of the RRSI based on a Modified Bouc-Wen model. This numerical model was simulated by using the specimens as base isolators for buildings.

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Real Estate, Usufruct Right and the Issue of the Waqf Assets in Egypt.

In the last decade, Egypt became more and more integrated with the global economy starting from its participation in the Union for Mediterranean (UfM), a partnership with the goal of creating a European Mediterranean Free Trade Area (EMFTA). Nevertheless, Egypt has been and still is an Islamic State still retaining some of the characteristics of the traditional Islamic legal system. This coexistence of Western practices and values of Islamic tradition makes it a fascinating case study in the field of economy and law. In this paper we will pay particular attention to the development of the law of real estate and land property in Egypt; specifically, we will illustrate how the Islamic character of Egyptian traditional law, attempts of international openness and Egyptian nationalism has combined together during the years. Firstly, we will summarise the key points in the process of reforms that have been put into practice starting from the Prime Ministerial decree 350/2007 establishing that companies and enterprises have the right to own real estates and lands regardless of their nationality or the nationality of their partners and shareholders. This opening to foreign companies was strongly discourage in 2012, by law no. 14 which gives the Minister of the Defence the responsibility of setting regulations concerning land attributions in the Sinai Peninsula. Minister of the Defence banned any foreigners land ownerships (so called ‘Sinai law’), this decision severely affecting the real estate market in the Sinai area, where foreign investments had been a key factor. In 2015 amendments to law no 14 have been introduced, loosening the restrictions on investors that wish to acquire land rights in the area on the Sinai Peninsula. It extends the scope of persons that are outside the range of the Sinai law allowing Non-Egyptians that receive title to a land by inheritance, testament or gift to keep the right of usufruct under certain conditions. We will then focus on the crucial role of the usufruct right. We point out that due to the above-mentioned legal innovation, the usufruct system in Egypt also upholds national security, and guarantees that land–especially that of a special nature like the Sinai Peninsula–will not fall into the hands of foreigners. A particular case of usufruct is the “ waqf ” or religious endowment, consisting of income-producing property whose usufruct is assigned by its original owner to a mosque or to carry out charitable works (e.g. building schools, orphanages and hospitals). The original owner of an endowed property retains his or her ownership in it, but the usufruct right is conveyed to an endowment authority. In Egypt, the Endowments Authority, established since 1971, is affiliated with the Ministry of Religious Endowments: it is the sole competent authority empowered to manage and invest in endowment assets. Such investments can have an impact in real estate system and in the usufruct right scheme in the name of a more pervasive State involvement in this field of investments. All these aspects will be broadly analysed in this paper.

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A reactivity-selectivity study of the Friedel-Crafts acetylation of 3,3'-dimethylbiphenyl and the oxidation of the acetyl derivatives.

BackgroundFriedel-Crafts acetylation is an important route to aromatic ketones, in research laboratories and in industry. The acetyl derivatives of 3,3′-dimethylbiphenyl (3,3′-dmbp) have applications in the field of liquid crystals and polymers and may be oxidized to the dicarboxylic acids and derivatives that are of interest in cancer treatment.FindingsThe effect of solvent and temperature on the selectivity of monoacetylation of 3,3’-dmbp by the Perrier addition procedure was studied using stoichiometric amounts of reagents. 4-Ac-3,3′-dmbp was formed almost quantitatively in boiling 1,2-dichloroethane and this is almost twice the yield hitherto reported. Using instead a molar ratio of substrate:AcCl:AlCl3 equal to 1:4:4 or 1:6:6 in boiling 1,2-dichloroethane, acetylation afforded 4,4′- and 4,6′-diacetyl-3,3′-dmbp in a total yield close to 100%. The acetyl derivatives were subsequently converted to the carboxylic acids by hypochlorite oxidation. The relative stabilities of the isomeric products and the corresponding σ-complexes were studied by DFT calculations and the data indicated that mono- and diacetylation followed different mechanisms.ConclusionsFriedel-Crafts acetylation of 3,3′-dmbp using the Perrier addition procedure in boiling 1,2-dichloroethane was found to be superior to other recipes. The discrimination against the 6-acetyl derivative during monoacetylation seems to reflect a mechanism including an AcCl:AlCl3 complex or larger agglomerates as the electrophile, whereas the less selective diacetylations of the deactivated 4-Ac-3,3′-dmbp are suggested to include the acetyl cation as the electrophile. The DFT data also showed that complexation of intermediates and products with AlCl3 does not seem to be important in determining the mechanism.

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