2 research outputs found

    One-pot synthesis of nano-crystalline MCM-22

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    [EN] Nano-crystalline MCM-22 zeolite was synthesized in a one-pot procedure by the use of an organosilane (dimethyl-octadecyl-(3-trimethoxysilylpropyl)-ammonium chloride, TPOAC) in the zeolite synthesis gel. This crystal growth inhibition procedure introduced mesopores in the MCM-22 crystallites. The lower mechanical stability of the nano-crystalline MCM-22 zeolite compared with bulk MCM-22 can be countered to some extent by pillaring. The increased external surface of the microporous zeolite domains resulted in increased accessibility of the Bronsted acid sites, as followed from the better performance in liquid-phase benzene alkylation with propylene as compared with bulk MCM-22. The increased accessibility of the internal acid sites in Mo-loaded hierarchical MCM-22 was also evident from the improved benzene selectivity during methane aromatization. Silylation of hierarchical Mo/MCM-22 was detrimental for the catalytic performance in MDA. The nano-crystalline MCM-22 has physico-chemical and catalytic properties intermediate between those of MCM-22 and ITQ-2 with the benefit over ITQ-2 that it can be synthesized in a single step. (C) 2015 Elsevier Inc. All rights reserved.Funding from the 7th Framework Program of the European Commission through the Collaborative Project Next-GTL (agreement no 229183) and financial support by the Spanish Government-MINECO through "Severo Ochoa" (SEV 2012-0267), Consolider Ingenio 2010-Multicat (CSD2009-00050) and MAT2012-31657 are acknowledged. Marta E. Martinez Armero thanks MINECO for economical support through pre-doctoral fellowship for doctors training (BES-2013-066800). The authors thank B. Esparcia for technical assistance.Tempelman, CHL.; Portilla Ovejero, MT.; MartĂ­nez Armero, ME.; Mezari, B.; De Caluwe, NGR.; MartĂ­nez, C.; Hensen, EJM. (2016). One-pot synthesis of nano-crystalline MCM-22. Microporous and Mesoporous Materials. 220:28-38. https://doi.org/10.1016/j.micromeso.2015.08.018S283822

    Making SENS: exploring the antecedents and impact of store environmental stewardship climate

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    Retailers increasingly recognize that environmental responsibility is a strategic imperative. However, little research has investigated or identified the factors that facilitate the successful implementation of environmentally responsible strategies across a network of customer-facing sales units (stores). We propose that a store manager’s ability to lead by example facilitates this process by fostering a supportive climate for store environmental stewardship (SENS-climate). By examining the influence of store managers’ actions on sales associates’ perceptions of the SENS-climate, as well as the subsequent impact on their performance—measured by margins, as well as sales of green and regular products—this study demonstrates that store managers can foster a SENS-climate by articulating their prioritization of environmental responsibility in their operational decisions. These positive effects are sustained by relational factors, such as the moderating effect of the store manager–sales associate dyadic tenure. In contrast, when store managers display high variability in their environmental orientation, it hinders the development of SENS-climate perceptions among sales associates. If sales associates perceive an enabling SENS-climate, they achieve higher margins and more green but fewer regular sales
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