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Nitrogen-containing activated carbons are materials of great interest. However, their main preparation methods are not able to control the formation of specific nitrogen groups on the carbon surface. The method here proposed is the selective nitrogen functionalization of activated carbons, by different oxidation and reduction treatments. Results indicated that the presence of stable phosphorus groups in the carbon obtained by chemical activation with phosphoric acid (ACP), favored the incorporation of higher amounts of nitrogen heteroatoms, mainly in form of nitro groups, during the treatment with only nitric acid. Subsequently, the activated carbons were reduced by thermal or chemical treatments, this last one by only using NaBH 4 as reducing reagent. Both methods were successfully used to reduce the nitro groups. Thermal reduction produced more condensed nitrogen (such as pyridinic and pyrrolic) structures in the activated carbons, containing (ACP) or not (AC) phosphorus groups on their surfaces. However, chemical reduction provided the selective formation of amine groups only with ACP carbons, suggesting the important role of phosphorus groups in the mechanism of amine formation. The presence of amine groups was confirmed by Ninhydrin test, for the first time, used in the detection of amino groups bonded to the carbon surface.

Influence of phosphorus on functionalization of activated carbons with nitric acid has been reviewed in this study. Results indicate that during treatment with nitric acid, phosphorus-containing carbons seem to graft more surface nitrogen, particularly as nitro groups, than those without phosphorus, where the nitrogen is found in lower oxidation state. A reaction pathway has been proposed to clarify the oxidation/nitration mechanism of phosphorus-containing carbons. The model consists of three independent mechanisms occurring simultaneously, with each one involving different phosphorus species present in the activated carbons.

We have developed a new graduate elective in the MSW degree program called Evaluacion e Intervencion en Espanol (Assessment and Intervention in Spanish). This class, taught entirely in Spanish, is designed to train Spanish-speaking MSW students in culturally and linguistically competent clinical practice with Hispanic clients. In this case study, we summarize the course.

This paper presents the results obtained from the IBE-CNC/DAQ-090827 project, conducted by the company “Titania Servicios Tecnolo´gicos, S.L.” in collaboration with the “Instituto de Seguridad Industrial, Radiofi´sica y Medioambiental” (ISIRYM), in the “Universidad Polite´cnica de Valencia”, for the company “Iberdrola Generacio´n S.A”. The objective is the acquisition of the pressure sensor signal and the measurement at points C85 and N32 from the cabin of the Turbine Control System in Cofrentes Nuclear Power Plant. With the study of previous data, one can obtain the Bode plot of the crossed signals as requested in the technical specification IM 0191 I. Frequency response (i.e. how the system varies its gain and offset depending on the frequency) defines the dynamics.

The synchronization of physiological and physical speech studies would seem to be the logical next step in analyses of their characteristics. Not only should a study be made of the physical characteristics as manifest in the oscillographic record, but the physiological position at any exact instant should also be known if a complete understanding is to be had. It is obvious that both records will have to be automatic. The x‐ray exposure time will have to be reduced to at least 1/120th of a second if a study of normal speech is to be made. Prolonged or sung vowels are not characteristic of normal speech. Consequently such x‐ray procedures have long since been discarded by careful investigators. Since motion picture x‐rays consisting of 1/120th of a second are not yet feasible, the instantaneous x‐ray exposure used in this study is chosen as the next best technique. Sound picture records likewise synchronized therewith serve as a check back on the final resultant.