62 research outputs found

    Estudio físico, químico y microestructural de geopolímeros base ceniza volante

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    En este trabajo se analizó el comportamiento físico, químico y microestructural de la ceniza volante activada alcalinamente. Para ello fueron utilizados diferentes tamaños de partícula de ceniza volante (CV), obtenidos por molienda manual, mezcladas con NaOH y curadas durante 7, 14 y 28 días. Las técnicas de caracterización utilizadas fueron: TGA, FTIR, MEB, adsorción física de gases y pruebas de resistencia a compresión, además del software NIVision Assistant. Los resultados muestran que la disminución de tamaño de partículas, favoreció la geopolimerización del gel N-A-S-H y mejoró las propiedades cementantes en los geopolímeros, logrando resistencias a compresión hasta de 23 MPa, por otro lado, se indica mediante análisis de imagen, que los porcentajes de porosidad en cada uno de los morteros evaluados disminuyen conforme se alejan de la zona de transición interfacial (ZTI), los cuales se corroboran con los resultados de porosimetría. (ANGLÈS) In this paper was analyzed the physical, chemical and microstructural behavior of alkali activated fly ash. This comparison was used with different particle sizes of fly ash (CV), obtained by manual milling, mixed with NaOH and cured for 7, 14 and 28 days. The characterization techniques used: TGA, FTIR, SEM, physical adsorption of gases and compressive strength tests, as well NIVision Assistant software. The results show that decreasing particle size favored NASH gel Geopolymerization and improved cementitious properties in geopolymer, achieving compressive strengths up to 23 MPa. On the other hand, indicated by image analysis, the percentages of porosity in each of the mortars evaluated decrease as they move away from the interfacial transition zone (ZTI), these results are corroborated by porosimetry method.Peer ReviewedPostprint (published version

    Efficacy of bendamustine and rituximab in unfit patients with previously untreated chronic lymphocytic leukemia. Indirect comparison with ibrutinib in a real-world setting. A GIMEMA-ERIC and US study

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    Limited information is available on the efficacy of front-line bendamustine and rituximab (BR) in chronic lymphocytic leukemia (CLL) with reduced renal function or coexisting conditions. We therefore analyzed a cohort of real-world patients and performed a matched adjusted indirect comparison with a cohort of patients treated with ibrutinib. One hundred and fifty-seven patients with creatinine clearance (CrCl) 6 were treated with BR. The median age was 72 years; 69% of patients had ≥2 comorbidities and the median CrCl was 59.8 mL/min. 17.6% of patients carried TP53 disruption. The median progression-free survival (PFS) was 45 months; TP53 disruption was associated with a shorter PFS (P = 0.05). The overall survival (OS) at 12, 24, and 36 months was 96.2%, 90.1%, and 79.5%, respectively. TP53 disruption was associated with an increased risk of death (P = 0.01). Data on 162 patients ≥65 years treated with ibrutinib were analyzed and compared with 165 patients ≥65 years treated with BR. Factors predicting for a longer PFS at multivariable analysis in the total patient population treated with BR and ibrutinib were age (HR 1.06, 95% CI 1.02-1.10, P < 0.01) and treatment with ibrutinib (HR 0.55, 95% CI 0.33-0.93, P = 0.03). In a post hoc analysis of patients in advanced stage, a significant PFS advantage was observed in patient who had received ibrutinib (P = 0.03), who showed a trend for OS advantage (P = 0.08). We arrived at the following conclusions: (a) BR is a relatively effective first-line regimen in a real-world population of unfit patients without TP53 disruption, (b) ibrutinib provided longer disease control than BR in patients with advanced disease stage

    Multimessenger NuEM Alerts with AMON

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    The Astrophysical Multimessenger Observatory Network (AMON), has developed a real-time multi-messenger alert system. The system performs coincidence analyses of datasets from gamma-ray and neutrino detectors, making the Neutrino-Electromagnetic (NuEM) alert channel. For these analyses, AMON takes advantage of sub-threshold events, i.e., events that by themselves are not significant in the individual detectors. The main purpose of this channel is to search for gamma-ray counterparts of neutrino events. We will describe the different analyses that make-up this channel and present a selection of recent results

    Nurses' perceptions of aids and obstacles to the provision of optimal end of life care in ICU

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    Contains fulltext : 172380.pdf (publisher's version ) (Open Access

    Estudio Comparativo de la porosidad en morteros de geopolímero por las técnicas de imagen y adsorción física de gases

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    La finalidad de esta investigación radica en evaluar los porcentajes de porosidad mediante la técnica no destructiva de análisis de imagen en muestras de morteros elaborados con ceniza volante activada alcalinamente, también llamados geopolímeros. Y además compararla con la técnica de adsorción física de gases comúnmente utilizada. Los resultados presentados muestran que a menor tamaño de partícula menor será el porcentaje de porosidad presente en los morteros, los cuales disminuyen conforme se alejan de la zona de transición interfacial (ZTI). La comparativa entre las técnicas anteriormente mencionadas arroja resultados de porosidad similares, destacando que la mayoría de los poros presentes en los morteros son de tipo mesoporoso. (ANGLÈS) The purpose of this investigation was assessing the percentage of non-destructive porosity by image analysis technique in samples of mortars made with alkali activated fly ash, also called geopolymer. And compared with the technique of physical adsorption of gases commonly used. The results presented show that the smaller the particle size smaller the percentage of porosity present in mortars, which decrease as they move away from the interfacial transition zone (ITZ). A comparison between the aforementioned techniques yields results similar porosity, noting that most of the pores present in mortars are mesoporous type

    Estudio Comparativo de la porosidad en morteros de geopolímeros por las técnicas de imagen y adsorción física de gases

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    La contaminación es una de las principales problemáticas, donde la industria de la construcción aporta. Aporta grandes emisiones de CO2 a la atmosfera con el uso de cemento Portland. La utilización de materiales cementantes suplementarios, provenientes de desecho industriales como la ceniza volante al ser activados alcalinamente adquieren propiedades mecánicas similares a las del cemento Portland.Peer Reviewe

    Estudio Comparativo de la porosidad en morteros de geopolímero por las técnicas de imagen y adsorción física de gases

    No full text
    La finalidad de esta investigación radica en evaluar los porcentajes de porosidad mediante la técnica no destructiva de análisis de imagen en muestras de morteros elaborados con ceniza volante activada alcalinamente, también llamados geopolímeros. Y además compararla con la técnica de adsorción física de gases comúnmente utilizada. Los resultados presentados muestran que a menor tamaño de partícula menor será el porcentaje de porosidad presente en los morteros, los cuales disminuyen conforme se alejan de la zona de transición interfacial (ZTI). La comparativa entre las técnicas anteriormente mencionadas arroja resultados de porosidad similares, destacando que la mayoría de los poros presentes en los morteros son de tipo mesoporoso. (ANGLÈS) The purpose of this investigation was assessing the percentage of non-destructive porosity by image analysis technique in samples of mortars made with alkali activated fly ash, also called geopolymer. And compared with the technique of physical adsorption of gases commonly used. The results presented show that the smaller the particle size smaller the percentage of porosity present in mortars, which decrease as they move away from the interfacial transition zone (ITZ). A comparison between the aforementioned techniques yields results similar porosity, noting that most of the pores present in mortars are mesoporous type.Postprint (published version
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