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The synthesis, spectroscopic characterization, and electrochemistry of 12 different neutral, singly and doubly oxidized heteroleptic double-decker complexes of the type [M^jPjjPc)]" where = 0, +1, or +2, M = Zr or Hf, P = the dianion of octaethylporphyrin (OEP) or tetraphenylporphyrin (TPP), and Pc = the dianion of phthalocyanine are reported. Each neutral compound was characterized by NMR, UV-visible, and IR spectroscopy while each oxidized or reduced compound was characterized by UV-visible and/or EPR spectroscopy. The neutral compounds all undergo two reversible ring-centered oxidations and two reversible ring-centered reductions.Comparison is made with data obtained for the corresponding actinide double-decker complexes containing Th(IV) or U(IV) central metal ions and correlations examined between £1/2 for all of the compounds and either the metal ionic radius or the absorbance band energy of the porphyrin Soret or phthalocyanine UV-band. The half-wave potentials depend upon the type of macrocycle. They also vary with the size of metal ion in the case of oxidation but not in reduction, where £1/2 values are relatively unaffected and shift by only 20-40 mV upon going from Hf(P)(Pc) to Th(P)(Pc) as compared to a much larger 220-280 mV shift between Em for the first oxidation of the same compounds.

Abstract:Purpose: The purpose of this paper is to explore obstacles to ISO 9001 quality management system implementation in Moroccan firms.Design/methodology/approach: A questionnaire survey has been conducted among a heterogeneous sample of 200 organizations, operating in different sectors in Morocco, yielding a response rate of 57.5%. The authors have studied barriers to quality initiatives in general and obstacles to QMS implementation in particular through an extensive literature review. Questions related to profiles of respondents, reasons of seeking certification, external consultancy and barriers to ISO 9001 implementation experienced by surveyed organizations. For the purpose of this study, authors considered three categories of quality inhibiting factors: organizational, technical and costs related barriers. Findings:Results indicate that surveyed companies sought ISO 9001 certification mainly for marketing reasons and experienced many difficulties during the implementation process. Barriers reported by respondents were mostly organizational. Resistance to change headed the list according to participants' opinion. Also, findings highlighted the prominence of bureaucracy and poor interdependence between departments in organizations. Lack of communication, poor top management commitment and insufficient trainings were also ascertained to be obstacles to QMS implementation in Morocco. Originality/value: Earlier studies were led by different researchers in different countries about barriers to quality initiatives in general and to ISO 9001 implementation in particular. Few of those studies were conducted in Arab speaking countries but no research has been carried in Morocco. This study on obstacles to QMS implementation in Morocco will help in completing the jigsaw of difficulties faced by organizations worldwide when preparing to ISO 9001 certification. Research limitations/implications:This research is limited by the geographic context of the study Morocco, although results can be extrapolated to Arab speaking countries in general. Practical implications:The findings of this paper provide Moroccan managers with a practical understanding of the factors that are likely to obstruct ISO 9001 QMS implementation. Managers should overcome these barriers to achieve a successful implementation and higher QMS performance.

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In order to master and improve the quality and properties of the final products, the major industrial challenge lies in the possibility of controlling the morphology, size of microstructures that reside within the molded pieces, as well as their defects; this is the fundamental reason according to which we are more and more interested in mastering the growth and germination of such alloys, as well as the developing structures, at the time of solidification process. The modeling reveals as a valuable aid in the mastery of the formation of such heterogeneousness: segregation cells that are incompatible with industrial requirements.   The whole work focuses upon the modeling of the segregation phenomenon of the four hypoeutectic alloys, Al1%Cu, Al2%Cu, Al3%Cu et Al4%Cu, as well as the copper effect upon certain mechanical properties of aluminum. Usually, the microstructure and mechanical behavior of such alloys as Al-Cu are directly influenced by some parameters such as composition, cooling velocity and homogenization process.