ABSTRACT
Failing to recognize the role of leaders in quality and equitable schooling is unfortunate and must be redressed. Leadership is fundamentally about organized agency and collective vision, not managerialism, since it is an organizational quality, not merely a positionality attribute. Most important, if change is to be systemic and transformative, it cannot occur uniquely at the individual teachers' level. School organization is fundamental to circulating and consolidating new innovative actions, cognitive schemes, and behaviors in coherent collective practices. This article engages with the relevance of governance patterns, school organization, and wider cultural and pedagogical factors that shape various leadership configurations. It formulates several assumptions that clarify the importance of leadership in any organized change. The way teachers act and represent their reality is strongly influenced by the architecture of their organization, while their ability to act with agency is directly linked to the existence of flat or prominent hierarchies, both potentially problematic for deep and systemic change. A hierarchical imposition from above as well as a lack of leadership vision in fragmented school cultures cannot determine any transformation.
ABSTRACT
In this manuscript an improved sorbent based on modified exfoliated carbon nanoplatelets, applied in the removal of ammonium from aqueous samples, is presented. This sorbent showed better efficiency in comparison with the previous one obtained in our group for ammonium removal, the values of the maximum sorption capacity being improved from 10 to 12.04 mg/g. In terms of kinetics and sorption characteristic parameters, their values were also improved. Based on these results, a sorption mechanism was proposed, taking into account ion-exchange and chemisorption processes at the surface of the oxidized exfoliated carbon nanoplatelets. Future applications for simultaneous removal of other positive charged contaminants from natural waters might be possible.
