Caracterización fisicoquímica de cuarzo en el municipio de La Playa de Belén, departamento de Norte de Santander

Quartz is a silicate, available in a variety of geological conditions, it appears in many igneous and metamorphic rocks, and it is a major constituent of granite pegmatite. Among minerals, quartz is the closest to a pure chemical compound and has constant physical properties, and due to their applications and uses it becomes a material that contributes to improving the living conditions of man. For that reason, it is necessary to know their properties to propose optimal applications. This work presents the physicochemical characterization of quartz in the municipality of La Playa de Belen (North Santander Department, Colombia) using elementary techniques through studies to establish the physical and chemical properties of this mineral. Techniques such as scanning electron microscopy (SEM) with disperse energy analyzer (EDS), X-ray diffraction (XRD), thermogravimetric (TGA) and differential thermogravimetric analysis (DTG) were used. The compositional, chemical and morphological characteristics are obtained, and the thermal behavior is evaluated according to the composition.El cuarzo es un silicato, se presenta en una gran variedad de condiciones geológicas, aparece en muchas rocas ígneas y metamórficas, y es un constituyente principal de pegmatitas graníticas. Entre los minerales, el cuarzo es el más próximo a un compuesto químico puro y tiene propiedades físicas constantes. Debido a sus aplicaciones y usos, se convierte en un material que contribuye a mejorar las condiciones de vida del hombre, por tal razón se hace evidente la necesidad de conocer sus propiedades para proponer aplicaciones óptimas. Este trabajo describe las propiedades físicas y químicas del cuarzo en el municipio de La Playa de Belén, departamento de Norte de Santander, Colombia, mediante el uso de técnicas elementales. Se utilizan las técnicas de Microscopía Electrónica de Barrido (MEB) con analizador de energías dispersas (EDS), difracción de rayos X (DRX), análisis termogravimétrico (TGA) y diferencial termogravimétrico (DTG). Con este análisis se obtuvieron las características composicionales, químicas, morfológicas y se evaluó el comportamiento térmico de acuerdo con la composición

Canto de cigarras

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Stents bronquiales bioabsorbibles y factores que afectan su velocidad de degradación

The causes that can lead to obstruction of the central airway can be of functional origin, due to obstruction of the light, organic parietal lesion or extrinsic compression; in turn, they can also be grouped into malignant and non-malignant obstructions. When an obstruction reduces more than 50% of the lumen of the airway causes debilitating symptoms and is an indication to implant a bronchial stent. The bronchial stents currently available are an incomplete solution for obstructions of the airways. On the other hand, an ideal bronchial stent must comply with many characteristics, such as being biocompatible, in many cases bioabsorbable, radio opaque, that does not generate an inflammatory reaction, having characteristics similar to those of the airway to decrease the accumulation of secretions, between others. For this reason, bioabsorbable bronchial stents are presented as an attractive alternative that offers certain advantages, although they are still in development. This article seeks to describe the advances around the bioabsorbable bronchial stents and the factors that affect the degradation of the polymers with which they have been manufactured.Las causas que pueden conducir a la obstrucción de la vía aérea central pueden ser de origen funcional, por obstrucción de la luz, por lesión orgánica parietal o compresión extrínseca; a su vez, también pueden agruparse en obstrucciones malignas y no malignas. Cuando una obstrucción reduce el 50 % de la luz de la vía aérea causa síntomas debilitantes y es una de las indicaciones para implantar un stent bronquial. Los stents bronquiales actualmente disponibles son una solución incompleta para las obstrucciones de las vías aéreas. Por otra parte, un stent bronquial ideal debe cumplir con muchas características, tales como ser biocompatible, en muchos casos bioabsorbible, radio opaco, que no genere reacción inflamatoria, tener características similares a las de la vía aérea para disminuir la acumulación de secreciones, entre otras. Por esta razón los stents bronquiales bioabsorbibles se presentan como una alternativa atractiva que ofrece ciertas ventajas, aunque aún se encuentran en desarrollo. El presente artículo busca describir los avances alrededor de los stents bronquiales bioabsorbibles y los factores que afectan la degradación de los polímeros con los cuales se han fabricado

Caracterización fisicoquímica de cuarzo en el municipio de La Playa de Belén, departamento de Norte de Santander

Quartz is a silicate, available in a variety of geological conditions, it appears in many igneous and metamorphic rocks, and it is a major constituent of granite pegmatite. Among minerals, quartz is the closest to a pure chemical compound and has constant physical properties, and due to their applications and uses it becomes a material that contributes to improving the living conditions of man. For that reason, it is necessary to know their properties to propose optimal applications. This work presents the physicochemical characterization of quartz in the municipality of La Playa de Belen (North Santander Department, Colombia) using elementary techniques through studies to establish the physical and chemical properties of this mineral. Techniques such as scanning electron microscopy (SEM) with disperse energy analyzer (EDS), X-ray diffraction (XRD), thermogravimetric (TGA) and differential thermogravimetric analysis (DTG) were used. The compositional, chemical and morphological characteristics are obtained, and the thermal behavior is evaluated according to the composition.El cuarzo es un silicato, se presenta en una gran variedad de condiciones geológicas, aparece en muchas rocas ígneas y metamórficas, y es un constituyente principal de pegmatitas graníticas. Entre los minerales, el cuarzo es el más próximo a un compuesto químico puro y tiene propiedades físicas constantes. Debido a sus aplicaciones y usos, se convierte en un material que contribuye a mejorar las condiciones de vida del hombre, por tal razón se hace evidente la necesidad de conocer sus propiedades para proponer aplicaciones óptimas. Este trabajo describe las propiedades físicas y químicas del cuarzo en el municipio de La Playa de Belén, departamento de Norte de Santander, Colombia, mediante el uso de técnicas elementales. Se utilizan las técnicas de Microscopía Electrónica de Barrido (MEB) con analizador de energías dispersas (EDS), difracción de rayos X (DRX), análisis termogravimétrico (TGA) y diferencial termogravimétrico (DTG). Con este análisis se obtuvieron las características composicionales, químicas, morfológicas y se evaluó el comportamiento térmico de acuerdo con la composición

CARACTERIZACIÓN FISICOQUÍMICA DE CUARZO EN EL MUNICIPIO DE LA PLAYA DE BELÉN DEPARTAMENTO NORTE DE SANTANDER

Quartz is a silicate, is available in a variety of geological conditions, appears in many igneous and metamorphic rocks, and is a major constituent of granite pegmatite. Among the minerals, quartz is the closest to a pure chemical compound and has constant physical properties due to their applications and uses becomes a material that contributes to improving the living conditions of man; for that reason becomes obvious know their properties to propose optimal applications. To this end the physicochemical characterization of quartz in the town of Playa of Belen Norte de Santander (Colombia) Department, using elementary techniques through studies to establish the physical and chemical properties of this mineral is described. A technique of scanning electron microscopy (SEM) was used to disperse energy analyzer (EDS), X-ray diffraction (XRD), thermogravimetric (TGA) and differential thermogravimetric analysis (DTG). The compositional, chemical and morphological characteristics are obtained and the thermal behavior of the composition according to is evaluated

Caracterización fisicoquímica de cuarzo en el municipio de La Playa de Belén, departamento de Norte de Santander

Quartz is a silicate, available in a variety of geological conditions, it appears in many igneous and metamorphic rocks, and it is a major constituent of granite pegmatite. Among minerals, quartz is the closest to a pure chemical compound and has constant physical properties, and due to their applications and uses it becomes a material that contributes to improving the living conditions of man. For that reason, it is necessary to know their properties to propose optimal applications. This work presents the physicochemical characterization of quartz in the municipality of La Playa de Belen (North Santander Department, Colombia) using elementary techniques through studies to establish the physical and chemical properties of this mineral. Techniques such as scanning electron microscopy (SEM) with disperse energy analyzer (EDS), X-ray diffraction (XRD), thermogravimetric (TGA) and differential thermogravimetric analysis (DTG) were used. The compositional, chemical and morphological characteristics are obtained, and the thermal behavior is evaluated according to the composition.El cuarzo es un silicato, se presenta en una gran variedad de condiciones geológicas, aparece en muchas rocas ígneas y metamórficas, y es un constituyente principal de pegmatitas graníticas. Entre los minerales, el cuarzo es el más próximo a un compuesto químico puro y tiene propiedades físicas constantes. Debido a sus aplicaciones y usos, se convierte en un material que contribuye a mejorar las condiciones de vida del hombre, por tal razón se hace evidente la necesidad de conocer sus propiedades para proponer aplicaciones óptimas. Este trabajo describe las propiedades físicas y químicas del cuarzo en el municipio de La Playa de Belén, departamento de Norte de Santander, Colombia, mediante el uso de técnicas elementales. Se utilizan las técnicas de Microscopía Electrónica de Barrido (MEB) con analizador de energías dispersas (EDS), difracción de rayos X (DRX), análisis termogravimétrico (TGA) y diferencial termogravimétrico (DTG). Con este análisis se obtuvieron las características composicionales, químicas, morfológicas y se evaluó el comportamiento térmico de acuerdo con la composición

Production of bioabsorbible nanoparticles of polycaprolactone by using a tubular recirculating system

Encapsulation and controlled release of substances using polymeric nanoparticles require that these have a high reproducibility, homogeneity, and control over their properties, especially when they are to be used in medical, pharmaceutical or nutritionalapplications among others. This work shows a high productivity system to synthesize nanoparticles in an easy, fast and controlled way.This study shows theeffect of molecular weight of the polymer, the type of surfactant and the relationship between the volumes of the aqueous andthe organic phases. Itwas found that the first two variables have a statistically significant effect on the diameter of the nanoparticles while the relationship between the volume of the aqueous phase and the organic phase does not significantly affect the diameter of the nanoparticles. Additionally, it was found that none of the three variables significantly affects the polydispersity index (PI) ofthe nanoparticle.La encapsulación y la liberación controlada de sustancias que utilizan nanopartículas poliméricas requieren que estas tengan una alta reproducibilidad, homogeneidad y control sobre sus propiedades, especialmente cuando se van a utilizar en aplicaciones médicas, farmacéuticas o nutricionales entre otras. Este trabajo muestra un sistema de alta productividad para sintetizar nanopartículas poliméricas de una forma fácil, rápida y de manera controlada.Este estudio muestra el efecto del peso molecular del polímero, el tipo de tensioactivo y la relación entre los volúmenes de las fases acuosa y orgánica. Se encontró que las dos primeras variables tienen un efectoestadísticamente significativo sobre el diámetro de las nanopartículas, mientras que la relación entre el volumen de la fase acuosa y la fase orgánica no afecta significativamente el diámetro de las nanopartículas. Además, se encontró que ninguna de las tres variables afecta significativamente el índice de polidispersidad de las nanopartículas

Production of bioabsorbible nanoparticles of polycaprolactone by using a tubular recirculating system

Encapsulation and controlled release of substances using polymeric nanoparticles require that these have a high reproducibility, homogeneity, and control over their properties, especially when they are to be used in medical, pharmaceutical or nutritional applications among others. This work shows a high productivity system to synthesize nanoparticles in an easy, fast and controlled way. This study shows the effect of molecular weight of the polymer, the type of surfactant and the relationship between the volumes of the aqueous and the organic phases. It was found that the first two variables have a statistically significant effect on the diameter of the nanoparticles while the relationship between the volume of the aqueous phase and the organic phase does not significantly affect the diameter of the nanoparticles. Additionally, it was found that none of the three variables significantly affects the polydispersity index (PI) of the nanoparticles

Production of bioabsorbible nanoparticles of polycaprolactone by using a tubular recirculating system

Encapsulation and controlled release of substances using polymeric nanoparticles require that these have a high reproducibility, homogeneity, and control over their properties, especially when they are to be used in medical, pharmaceutical or nutritional applications among others. This work shows a high productivity system to synthesize nanoparticles in an easy, fast and controlled way. This study shows the effect of molecular weight of the polymer, the type of surfactant and the relationship between the volumes of the aqueous and the organic phases. It was found that the first two variables have a statistically significant effect on the diameter of the nanoparticles while the relationship between the volume of the aqueous phase and the organic phase does not significantly affect the diameter of the nanoparticles. Additionally, it was found that none of the three variables significantly affects the polydispersity index (PI) of the nanoparticles

Tribological properties of carbon nanotubes as lubricant additive in oil and water for a wheel–rail system

Since their discovery in 1991 carbon nanotubes (CNTs) have attracted much interest due to their remarkable mechanical, thermal, electrical, chemical and optical properties. In connection with their mechanical properties, CNTs have been studied in various forms for tribological applications including their use as lubricant additives for oil and water. In this work, the tribological properties of functionalized nanotubes (single and multi-walled) modified with carboxylic acid when used as lubricant additives at different concentrations (0.01, 0.05%) were studied under rolling-sliding conditions in a twin-disk testing machine. The tests were performed using 5% of creepage and pressures of 0.8 GPa and 1.1 GPa. The results indicated that the presence of carbon nanotubes leads to a decrease in both friction coefficient and wear rate for both systems studied (oil and water)