En este trabajo el primer paso consistió en llevar a cabo un suavizado y un filtrado de la señal, con el fin de eliminar el ruido y la información no relevante. La segunda parte consiste en la ...determinación automática de las longitudes de onda de los picos o máximos. Luego, se lleva a cabo la identificación elemental química de los picos empleando una base de datos especializada. Después de esto, el software permite la determinación de características necesarias para los cálculos como intensidad, FWHM (por su sigla en inglés Full Width at half Maximum, en español Ancho total a la Mitad del Máximo), los valores del continuo y el perfil de las líneas. Estos parámetros fueron empleados junto con métodos espectroscópicos tales como la gráfica de Boltzmann, relación entre intensidades de líneas de diferente grado de ionización y relación línea-continuo para determinar Texc= 4778.32 K, n e=2.54 10(17) cm-3 y Te= 2668 K respectivamente. Estos valores son similares a los reportes, para este tipo de plasmas. El beneficio principal del software consintió en llevar a cabo todo el estudio del plasma en tiempo muy corto (del orden de segundos), mientras que su análisis manual puede tomar varios días.
•We synthesise fluorogenic sensory monomer and polymer for detecting Al(III).•The sensory polymer is a solid manageable crosslinked film, or dense membrane.•The solid system is used as a solid kit ...for “dip-in” Al(III) detection.•The detection of Al(III) is carried out in pure water media.•The detection limit of Al(III) by the sensory material is in the ppb range.
A solid substrate comprised of a cross-linked polymer network is shaped as a film with gel-like behaviour and is used to detect aluminium ions in water; concurrently, a water soluble sensory polymer synthesised towards the same purpose is also discussed. The detection in both systems was achieved via fluorescence “turn-on”. The limits of detection for Al(III) were 1.6 and 25ppb for the former and latter materials, respectively; these levels are significantly lower than the EPA recommendations for drinking water.
This work aims to improve the outstanding thermal and mechanical properties of commercialized wholly aromatic polyamide fibers (i.e., aramids), by crosslinking the materials. The introduction of a ...reactive azide group into the polymer structure leads to functional aramids. Crosslinking processes can be easily performed using an inexpensive thermal treatment after fiber spinning with current spin production facilities.
This work describes the strategy of crosslinking aromatic polyamides to increase the outstanding thermal and mechanical performances of these materials. The introduction of a reactive azide group into the polymer structure leads to a 3D network after transformation and upon heating. An important fact is that cross‐linking can be easily achieved with current aramid fiber production facilities.
This study developed sensory polymeric materials for the colorimetric sensing of TNT in aqueous media. Solid films and coated fabrics permitted the detection of TNT, through colour change, and its ...quantification, by taking a picture of the materials and processing their RGB parameters to define the evolved colour.
The naked eye detection of TNT in aqueous environments using solid colorimetric sensory polymers and fibres, and in surfaces using water-soluble sensory polymers.
A water-insoluble organic chemosensor has been chemically modified by introducing a polymerizable methacrylamide moiety via copolymerization with a hydrophilic comonomer (vinylpyrrolidone), producing ...a water-soluble acrylic copolymer that is able to sense environmentally poisonous cations in pure aqueous media. The chemosensor is a derivative of Rhodamine B, which behaves as a fluorescent and chromogenic sensor toward various heavy cations, particularly Hg(II). Titration curves of Hg(II) were constructed using rapid, cheap, and widely available techniques, such as fluorescence and UV/Vis spectroscopies. Furthermore, a colorimetric response from the copolymer chemosensor permitted the detection of Hg(II) by eye due to the development of a pink color when this cation interacted with the copolymer in aqueous media.
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▶ A chromogenic and fluorogenic copolymer chemosensor has been prepared. ▶ The sensory material permits the detection and quantification of mercury cations. ▶ The sensory motif, a Rhodamine dye, was hydrophobic and insoluble in water. ▶ However, the prepared copolymer was highly hydrophilic and water soluble. ▶ This methodology allows the exploitation of water insoluble organic dyes in water.
We have designed and successfully prepared polymer membranes as manageable films for colorimetric sensor materials for the visual detection of the acidity of water in the low pH range, below 4, and ...beyond the pH scale, up to a concentration of 11.6 M of perchloric acid. For this purpose, two monomers with weakly basic groups were synthesised, with these monomers containing up to four protonisable groups in the aforementioned acidic regions. The p K a values were calculated for the membranes in water, which exhibited gel behaviour, and ranged between 2.7 and −6.5. Accordingly, visual colour changes qualitatively indicated the acidity of water containing perchloric acid, and the quantification was performed inexpensively by UV/Vis spectroscopy. Titration with other acids is foreseen for practical applications. Moreover, polymer coatings of conventional cotton and high-tech p -aramid fibres, using the designed sensor monomers, yielded smart fabrics, which responded colorimetrically to the acidity of the water media. Furthermore, both membranes and smart fibres exhibited colour changes in air under acidic atmospheres, demonstrating the future development of fully sensory apparels and smart tags with envisaged health and safety applications. In addition, the sensor materials are reusable, because the protonation under acidic conditions is reverted by washing with water, and are highly stable under acidic conditions for long periods of time.
This work describes the design of efficient, inexpensive and easily prepared selective sensory polymers with chemically anchored amine groups as 2,4,6-trinitrotoluene (TNT)-sensing motifs as ...materials for the selective visual detection of TNT in aqueous media and as vapours. The materials are prepared as handleable sensory films or dense membranes from which sensory discs are cut, as well as smart fibres by coating conventional and commercial cotton fabrics. Both types of material exhibited a highly visible colour development from colourless to red upon contact with TNT both in the gas phase and in solution, and the colour change was used to build titration curves using the colour definition parameters of a digital image acquired with a smartphone, i.e. , the RGB system. The materials were selective, remaining silent with other nitroaromatic compounds, such as 4-nitrotoluene and 2,4-dinitrotoluene, and the detection limit in solution was close to the micromolar range.
We present colorimetric sensory membranes for detecting Hg(ii) in aqueous media. The colour response of the sensory materials can be tuned for detection with the naked eye, such as the maximum ...contaminant level of Hg(ii) that is set by the United States Environmental Protection Agency (EPA) for drinking water. Furthermore, the concentration of Hg(ii) can be monitored using digital pictures of the membranes taken with conventional cameras. Thus, nanomolar concentration of Hg(ii) could be detected by the naked eye due to colour changes of membranes, and the concentration of Hg(ii) could be quantified, within the millimolar to nanomolar range, by means of analysing the digital information of pictures taken of the membranes after dipping them in water containing this environmentally poisonous cation.
We have designed and successfully prepared polymer membranes as manageable films for colorimetric sensor materials for the visual detection of the acidity of water in the low pH range, below 4, and ...beyond the pH scale, up to a concentration of 11.6 M of perchloric acid. For this purpose, two monomers with weakly basic groups were synthesised, with these monomers containing up to four protonisable groups in the aforementioned acidic regions. The p
K
a
values were calculated for the membranes in water, which exhibited gel behaviour, and ranged between 2.7 and −6.5. Accordingly, visual colour changes qualitatively indicated the acidity of water containing perchloric acid, and the quantification was performed inexpensively by UV/Vis spectroscopy. Titration with other acids is foreseen for practical applications. Moreover, polymer coatings of conventional cotton and high-tech
p
-aramid fibres, using the designed sensor monomers, yielded smart fabrics, which responded colorimetrically to the acidity of the water media. Furthermore, both membranes and smart fibres exhibited colour changes in air under acidic atmospheres, demonstrating the future development of fully sensory apparels and smart tags with envisaged health and safety applications. In addition, the sensor materials are reusable, because the protonation under acidic conditions is reverted by washing with water, and are highly stable under acidic conditions for long periods of time.
Reusable smart films and textiles as colorimetric sensor materials for high acidity environments.
El presente estudio presenta una revisión de la literatura de artículos publicados entre los años 2012 al 2022 en distintos países, sobre el tema del uso de las tecnologías en los niveles de primaria ...y secundaria, como base para el desarrollo del talento tecnológico. La metodología utilizada fue con un enfoque cualitativo-documental, con una búsqueda en diferentes bases de datos, de donde se depuraron un total de 22 investigaciones encontradas en torno al tema. Los resultados del análisis permitieron establecer cuatro ejes temáticos: los alumnos con aptitudes sobresalientes, las cuestiones de género, la tecnología y la escuela y los retos a enfrentar por parte del estudiantado con aptitudes sobresalientes y/o talento tecnológico. También se encuentra que en España se ha efectuado más trabajo en la temática, así como que el enfoque mayormente utilizado en los artículos analizados es el cuantitativo y la técnica que más aparece es el uso de cuestionarios. Se concluye que es necesario tener más estudios sobre el desarrollo del talento tecnológico a edades tempranas, pues existe poca literatura sobre el tema, no se abordan aspectos específicos de estos casos y existe una brecha todavía muy amplia para establecer condiciones y contextos donde se puede desarrollar este tipo de talento.
