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The preparation and characterization of two families of building blocks for molecule-based magnetic and conducting materials are described in three projects. In the first project the synthesis and characterization of three bis-imine ligands LI - L3 is reported. Coordination of LI to a series of metal salts afforded the five novel coordination complexes Sn(L4)C4 (I), [Mn(L4)(u-CI)(CI)(EtOH)h (II), [CU(L4)(u-sal) h(CI04)2 (sal = salicylaldehyde anion) (III), [Fe(Ls)2]CI (IV) and [Fe(LI)h(u-O) (V). All complexes have been structurally and magnetically characterized. X-ray diffraction studies revealed that, upon coordination to Lewis acidic metal salts, the imine bonds of LI are susceptible to nucleophilic attack. As a consequence, the coordination complexes (I) - (IV) contain either the cyclised ligand L4 or hydrolysed ligand Ls. In contrast, the dimeric Fe3+ complex (V) comprises two intact ligand LI molecules. In. this complex, the ligand chelates two Fe(III) centres in a bis-bidentate manner through the lone pairs of a phenoxy oxygen and an imine nitrogen atom. Magnetic studies of complexes (II-V) indicate that the dominant interactions between neighbouring metal centres in all of the complexes are antiferromagnetic. In the second project the synthesis and characterization two families of TTF donors, namely the cyano aryl compounds (VI) - (XI) and the his-aryl TTF derivatives (XII) - (XIV) are reported. The crystal structures of compounds (VI), (VII), (IX) and (XII) exhibit regular stacks comprising of neutral donors. The UV -Vis spectra of compounds (VI) - (XIV) present an leT band, indicative of the transfer of electron density from the TTF donors to the aryl acceptor molecules. Chemical oxidation of donors (VI), (VII), (IX) and (XII) with iodine afforded a series of CT salts that where possible have been characterized by single crystal X -ray diffraction. Structural studies showed that the radical cations in these salts are organized in stacks comprising of dimers of oxidized TTF donors. All four salts behave as semiconductors, displaying room temperature conductivities ranging from 1.852 x 10-7 to 9.620 X 10-3 Scm-I. A second series of CT salts were successfully prepared via the technique of electrocrystallization. Following this methodology, single crystals of two CT salts were obtained. The single crystal X-ray structures of both salts are isostructural, displaying stacks formed by trimers of oxidized donors. Variable temperature conductivity measurements carried out on this series of CT salts reveal they also are semiconductors with conductivities ranging from 2.94 x 10-7 to 1.960 X 10-3 S em-I at room temperature. In the third project the synthesis and characterization of a series of MII(hfac)2 coordination complexes of donor ligand (XII) where M2+ = Co2+, Cu2+, Ni2+ and Zn2+ are reported. These complexes crystallize in a head-to-tail arrangement of TTF donor and bipyridine moieties, placing the metal centres and hfac ligands are located outside the stacks. Magnetic studies of the complexes (XV) - (XVIII) indicate that the bulky hfac ligands prevent neighbouring metal centres from assembling in close proximity, and thus they are magnetically isolated.

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Receipts from the Park Lawn Cemetery Co. Ltd., Bloor St. West, Toronto. Receipt no. 851 for payment in full for a Lot no.91 in section H received from Percy C. Bands [Band]. Receipt no. 852 for payment for corner stones for Lot no.91 in section H received from Percy C. Bands [Band]. The unnumbered receipt is for opening an adult grave for Sarah Lawrence. Payment was received from Percy C. Bands [Band], Feb. 23, 1926.

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UANL

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Affiliation: Pierre Dagenais : Hôpital Maisonneuve-Rosemont, Faculté de médecine, Université de Montréal

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ABSTRACT: Polyaniline was synthesized by using ammonium persulfate initiator in the presence of 1M HC1. It was dried under different drying conditions like room temperature drying (for 48 h), oven drying (at 50-60°C for 8 h under a vacuum), and vacuum drying (at room temperature for 16 h). The conductivities of these samples were measured at microwave frequencies. These samples were also pelletized and the measurements were repeated. The cavity perturbation technique was used for the study.

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This thesis investigates a method for human-robot interaction (HRI) in order to uphold productivity of industrial robots like minimization of the shortest operation time, while ensuring human safety like collision avoidance. For solving such problems an online motion planning approach for robotic manipulators with HRI has been proposed. The approach is based on model predictive control (MPC) with embedded mixed integer programming. The planning strategies of the robotic manipulators mainly considered in the thesis are directly performed in the workspace for easy obstacle representation. The non-convex optimization problem is approximated by a mixed-integer program (MIP). It is further effectively reformulated such that the number of binary variables and the number of feasible integer solutions are drastically decreased. Safety-relevant regions, which are potentially occupied by the human operators, can be generated online by a proposed method based on hidden Markov models. In contrast to previous approaches, which derive predictions based on probability density functions in the form of single points, such as most likely or expected human positions, the proposed method computes safety-relevant subsets of the workspace as a region which is possibly occupied by the human at future instances of time. The method is further enhanced by combining reachability analysis to increase the prediction accuracy. These safety-relevant regions can subsequently serve as safety constraints when the motion is planned by optimization. This way one arrives at motion plans that are safe, i.e. plans that avoid collision with a probability not less than a predefined threshold. The developed methods have been successfully applied to a developed demonstrator, where an industrial robot works in the same space as a human operator. The task of the industrial robot is to drive its end-effector according to a nominal sequence of grippingmotion-releasing operations while no collision with a human arm occurs.

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Resumen basado en el de la publicaci??n

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Resumen basado en el de la publicaci??n

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Resumen basado en el de la publicaci??n

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El libro se divide en cuatro capítulos en cada uno de los cuales las autoras presentan una serie de esquemas sobre temas relacionados con la orientación escolar: el marco de referencia (antecedentes y LOGSE), la planificación de programas de Orientación, el diseño de programas y su evaluación, además de una guía y actividades prácticas.

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El contenido de la asignatura, en mi caso del Derecho Financiero y Tributario debe ser transmitido a los alumnos. Esto, que en sí es una perogrullada, lamentablemente no siempre se tiene presente cuando el profesor, encaramado a la tarima, se enfrenta al alumnado. Pero hay que tener bien presente, que la función de todo profesor es la de transmitir conocimientos. (...)

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En muchas ocasiones, el alumnado no es capaz de establecer relaci??n entre la obra literaria y su propio entorno. Piensan que las creaciones literarias pertenecen a un mundo remoto en el tiempo y en el espacio. No obstante, tienen referencias indirectas de que su ciudad ha sido cuna o residencia de algunos autores famosos. El paseo literario es una actividad complementaria que tiene como objetivo reducir ese distanciamiento entre la obra literaria y el entorno cotidiano del alumnado, mostr??ndole que comparte con los autores un mismo referente. Adem??s se promueven objetivos relacionados con el inter??s por la lectura y la creaci??n literaria, as?? como la valoraci??n de la cultura e historia de su entorno. Para que esta actividad alcance los objetivos previstos es necesario prepararla cuidadosamente y con cierta antelaci??n en clase.