Structural and microstructural characterization of tin(II) oxide useful as anode material in lithium rechargeable batteries obtained from a different synthesis route at room temperature

Monthly market at Pinsk. Garlic in strings of one foot in length, cost 50 gr. Each. The men in the picture are all wearing boots or shoes. The women are bare footed. This is often the case in Poland. The men rarely go bare footed. October 3, 1934.P1766; 10-34GrayscaleLouise A. Boyd, Box 53

Evaluación del desempeño del pretratamiento con peróxido de hidrógeno sobre bagazo de caña de azúcar para remoción de lignina

La producción de bioetanol otorga beneficios ambientales, económicos y sociales, reduce la dependencia y preserva las fuentes energéticas fósiles. Esta investigación evaluó el desempeño del pretratamiento químico oxidativo con peróxido de hidrógeno (H2O2) para aumentar la disponibilidad de la celulosa, a partir de mezclas de biomasas lignocelulósicas como bagazo de caña panelero y hojarasca, en proporción (90:10). Fueron evaluadas tres variables (tiempo, temperatura y concentración) utilizando un diseño experimental 23 con triplicado en el punto central, se alcanzó una remoción de lignina del 70% con condiciones de reacción a 60 min, 45°C, 5% de peróxido de hidrógeno. Los resultados obtenidos en la etapa de pretratamiento a 25°C presentaron un buen rendimiento del 88,5% de remoción de lignina soluble y 79,5% de remoción de lignina insoluble a diferentes concentraciones, tales como 7% y 3% de peróxido de hidrógeno, durante un tiempo de 80 y 40 minutos, respectivamente. El diseño experimental identificó las variables significativas del modelo, las cuales fueron el tiempo, la temperatura y la interacción 1*3 que corresponde al tiempo y la concentración, con un 95% de confianza, se trazaron las superficies de respuesta para ver la tendencia de estas interacciones, estableciendo las condiciones óptimas del proceso para reducir costos y tiempo.Bioethanol production provides environmental, economic and social benefits, reduces dependency and preserves fossil energy sources. This investigation evaluated the performance of oxidative chemical pretreatment with hydrogen peroxide (H2O2), to increase the availability of cellulose, from mixtures of lignocellulosic biomasses such as bagasse from panelero cane, and litter, in proportion (90:10), carried out in order to evaluate the behavior of the biomasses when they are mixed, maintaining a greater proportion of sugarcane bagasse. Three variables were evaluated (time, temperature, and concentration) using an experimental design 23 with triplicate in the central point, a lignin removal of 70% was achieved with reaction conditions at 60 min, 45 ° C, 5% peroxide hydrogen. The results obtained in the pretreatment stage show a good removal performance of insoluble lignin of 88.5% with effect conditions at 80 min, 25 ° C, 7% hydrogen peroxide and a yield of 79.5% removal under conditions at 40 min, 25 ° C, 3% hydrogen peroxide. For soluble lignin with 58.8% removal and conditions at 80 min, 25 ° C, 7% hydrogen peroxide, and a reagent yield of 61.67% at 40 min conditions, 25 ° C 7% hydrogen peroxide. The experimental design shows by means of a statistical analysis the conditions of the process to reduce costs and time, identifying from the significant variables of the model that time, temperature and interaction 1 * 3 that corresponds to time and concentration, with 95% confidence, will bring the surfaces and respond to see the trend of these interactions

A comparative study on conversion of industrial coal by-products in low sio2 zeolite of faujasite type

Colombian industrial coal by-products were evaluated as raw materials in the synthesis at laboratory scale of low SiO2 zeolite of faujasite type using an alkaline fusion step followed by the hydrothermal treatment under various experimental conditions. By fusion with NaOH followed by hydrothermal reaction, coal by-products were converted into zeolite of faujasite type. The process of faujasite formation is discussed

Ciguatoxin-like toxicity distribution in flesh of amberjack (Seriola spp.) and dusky grouper (Epinephelus marginatus)

Ciguatoxins (CTXs) are marine neurotoxins that cause ciguatera poisoning (CP), mainly through the consumption of fish. The distribution of CTXs in fish is known to be unequal. Studies have shown that viscera accumulate more toxins than muscle, but little has been conducted on toxicity distribution in the flesh, which is the main edible part of fish, and the caudal muscle is also most commonly targeted for the monitoring of CTXs in the Canary Islands. At present, whether this sample is representative of the toxicity of an individual is undisclosed. This study aims to assess the distribution of CTXs in fish, considering different muscle samples, the liver, and gonads. To this end, tissues from four amberjacks (Seriola spp.) and four dusky groupers (Epinephelus marginatus), over 16.5 kg and captured in the Canary Islands, were analyzed by neuroblastoma-2a cell-based assay. Flesh samples were collected from the extraocular region (EM), head (HM), and different areas from the fillet (A-D). In the amberjack, the EM was the most toxic muscle (1.510 CTX1B Eq·g−1), followed by far for the caudal section of the fillet (D) (0.906 CTX1B Eq·g−1). In the dusky grouper flesh samples, D and EM showed the highest toxicity (0.279 and 0.273 CTX1B Eq·g−1). In both species, HM was one of the least toxic samples (0.421 and 0.166 CTX1B Eq·g−1). The liver stood out for its high CTX concentration (3.643 and 2.718 CTX1B Eq·g−1), as were the gonads (1.620 and 0.992 CTX1B Eq·g−1). According to these results, the caudal muscle next to the tail is a reliable part for use in determining the toxicity of fish flesh to guarantee its safe consumption. Additionally, the analysis of the liver and gonads could provide further information on doubtful specimens, and be used for CTX monitoring in areas with an unknown prevalence of ciguatera.info:eu-repo/semantics/publishedVersio

First Report on the Geologic Occurrence of Natural Na–A Zeolite and Associated Minerals in Cretaceous Mudstones of the Paja Formation of Vélez (Santander), Colombia

© 2021 The Authors. Published by MDPI. This is an open access article available under a Creative Commons licence. The published version can be accessed at the following link on the publisher’s website: https://doi.org/10.3390/cryst11020218This study reports for the first time the geologic occurrence of natural zeolite A and associated minerals in mudstones from the Cretaceous Paja Formation in the urban area of the municipality of Vélez (Santander), Colombia. These rocks are mainly composed of quartz, muscovite, pyrophyllite, kaolinite and chlorite group minerals, framboidal and cubic pyrite, as well as marcasite, with minor feldspar, sulphates, and phosphates. Total organic carbon (TOC), total sulfur (TS), and millimeter fragments of algae are high, whereas few centimeters and not biodiverse small ammonite fossils, and other allochemical components are subordinated. Na–A zeolite and associated mineral phases as sodalite occur just beside the interparticle micropores (honeycomb from framboidal, cube molds, and amorphous cavities). It is facilitated by petrophysical properties alterations, due to processes of high diagenesis, temperatures up to 80–100 °C, with weathering contributions, which increase the porosity and permeability, as well as the transmissivity (fluid flow), allowing the geochemistry remobilization and/or recrystallization of pre-existing silica, muscovite, kaolinite minerals group, salts, carbonates, oxides and peroxides. X-ray diffraction analyses reveal the mineral composition of the mudstones and scanning electron micrographs show the typical cubic morphology of Na–A zeolite of approximately 0.45 mμ in particle size. Our data show that the sequence of the transformation of phases is: Poorly crystalline aluminosilicate → sodalite → Na–A zeolite. A literature review shows that this is an unusual example of the occurrence of natural zeolites in sedimentary marine rocks recognized around the world.Published onlin

Estudio estructural de un derivado metálico del ácido α-hidroxicarboxílico

En este trabajo se estudia la sintesis y caracterización del bencilato de cesio, aben-cs. El compuesto se obtuvo mediante la mezcla en agitación contínua, por 2 horas a temperatura ambiente, de una solución acuosa de ácido bencílico y carbonato de cesio en una relación molar 1:1. El aben-cs se caracterizó por espectroscopia infrarroja con transformadas de Fourier, difracción de rayos-X de cristal único y de muestras policristalinas. El compuesto cristaliza en el sistema ortorrómbico, con grupo espacial Pbca con parámetros de celda a= 7,4232(5) Å, b=13,998(1) Å, c=25,998(2) Å. En el arreglo cristalino se observan principalmente interacciones intermoleculares del tipo ion dipolo y puente de hidrógeno.Cesium benzilate Aben-cs was obtained by mixing under continuous stirring for 2 hours at room temperature, an aqueous solution of benzylic acid and cesium carbonate in a molar ratio 1: 1. This new complex was characterized by FT-IR, single crystal and polycrystalline X-ray diffraction. The compound aben-cs crystallizes in the orthorhombic system, space group Pbca, with cell parameters a = 7.4232 (5) Å, b = 13,998 (1) Å, c = 25.998 (2) Å. The crystal packing is governed by hydrogen bonding and ion-dipole interactions

Estudio arqueométrico de la composición mineral y química de la cerámica pre-Hispánica de “Los Teres”, Mesa de Los Santos (Colombia)

  A set of selected fragments of pre-Hispanic pottery sherds that were excavated from the Mesa de Los Santos region’s archaeological site (Colombia) were investigated by different analytical techniques and principal component and hierarchical cluster analyses. This study is very useful to understand more about the raw materials (and provenance) for ancient pottery production and their manufacturing technology. In addition to establish stratigraphic and anthropological relationships, the pottery sherds were analyzed to determine their mineralogical and chemical composition, as well as their structural characteristics using X-ray powder diffraction, wavelength dispersive X-ray fluorescence, scanning electron microscopy, and attenuated total reflectance Fourier transform infrared spectroscopy. The results indicated that the pre-Hispanic pottery sherds were manufactured using poor carbonates and iron oxide-bearing clays with no significant changes in the technology of manufacture, firing the pastes at the proper temperatures or selecting and processing the raw materials to fulfill their use. The manufacture of pre-Hispanic pottery was probably carried out using local raw materials, compatible with the regional geological context, and the archaeometric study reveals that the pre-Hispanic cultures who lived in this region hardly had access to trade of raw materials.  Un conjunto de fragmentos seleccionados de tiestos de cerámica pre-Hispánica que fueron excavados del sitio arqueológico de la región de la Mesa de Los Santos (Colombia) fueron investigados por diferentes técnicas analíticas y componentes principales y análisis de conglomerados jerárquicos. Este estudio es muy útil para comprender más sobre las materias primas (y procedencia) para la producción de cerámica antigua y su tecnología de fabricación. Además de establecer relaciones estratigráficas y antropológicas, se analizaron los tiestos de cerámica para determinar su composición mineralógica y química, así como sus características estructurales mediante difracción de rayos X de polvos, Fluorescencia de rayos X de dispersión por longitud de onda, microscopía electrónica de barrido y espectroscopía infrarroja con transformadas de Fourier - reflectancia total atenuada. Los resultados indicaron que los tiestos de cerámica pre-Hispánica se fabricaron utilizando arcillas pobres en carbonatos y óxidos de Fe sin cambios significativos en la tecnología de fabricación, cociendo las pastas a las temperaturas adecuadas o seleccionando y procesando las materias primas para cumplir con su uso. La fabricación de cerámica pre-Hispánica probablemente se llevó a cabo utilizando materias primas locales, compatibles con el contexto geológico regional, y el estudio arqueométrico revela que las culturas pre-Hispánicas que vivían en esta región difícilmente tuvieron acceso al comercio de materias primas.

Rapid health evaluation in migrant peoples in transit through Darien, Panama: protocol for a multimethod qualitative and quantitative study.

BACKGROUND: The world is currently unprepared to deal with the drastic increase in global migration. There is an urgent need to develop programs to protect the well-being and health of migrant peoples. Increased population movement is already evident throughout the Americas as exemplified by the rising number of migrant peoples who pass through the Darien neotropical moist broadleaf forest along the border region between Panama and Colombia. The transit of migrant peoples through this area has an increase in the last years. In 2021, an average of 9400 people entered the region per month compared with 2000-3500 people monthly in 2019. Along this trail, there is no access to health care, food provision, potable water, or housing. To date, much of what is known about health needs and barriers to health care within this population is based on journalistic reports and anecdotes. There is a need for a comprehensive approach to assess the health care needs of migrant peoples in transit. This study aims to describe demographic characteristics, mental and physical health status and needs, and experiences of host communities, and to identify opportunities to improve health care provision to migrant peoples in transit in Panama. STUDY DESIGN AND METHODS: This multimethod study will include qualitative (n = 70) and quantitative (n = 520) components. The qualitative component includes interviews with migrant peoples in transit, national and international nongovernmental organizations and agencies based in Panama. The quantitative component is a rapid epidemiological study which includes a questionnaire and four clinical screenings: mental health, sexual and reproductive health, general and tropical medicine, and nutrition. CONCLUSION: This study will contribute to a better understanding of the health status and needs of migrant peoples in transit through the region. Findings will be used to allocate resources and provide targeted health care interventions for migrant peoples in transit through Darien, Panama

Innovación turística y desarrollo regional

Libro que se compila 14 capítulos asociados a las temáticas de innovación y desarrollo tecnológico en el sector turístico, emprendimiento y tecnologías emergentes, políticas estratégicas y tácticas para mejorar la competitividad en las empresas, políticas públicas y educación para el desarrollo regional y responsabilidad social ambientalBook that compiles 14 chapters associated to the themes of innovation and technological development in the tourism sector, entrepreneurship and emerging technologies, strategic and tactical policies to improve competitiveness in companies, public policies and education for regional development and environmental social responsibilityInnovación social como estrategia para el desarrollo de las poblaciones palafíticas de la ciénaga grande de santa marta mediante la oferta de productos turísticos / Gregoria Polo de Lobatón; José Luis Rosenstiehl Martínez; Daulis Lobatón Polo -- Uso de las tic para mejorar la competitividad turística en San Basilio de Palenque / Jesús Llerena Cabrera; Raúl José Martelo Gómez; David Franco Borré -- Plataforma web niu (nuevo, ideas y usados) / Néstor José Ocampo Ardila -- Posicionamiento estratégico del turismo urbano de eventos como atributo de la personalidad del espacio territorial de la ciudad de santa marta / Zuleidy María Ruíz Torres -- Identificación competitiva de la oferta exportadora de la región ariari para fortalecer el desarrollo social y económico en zonas de posconflicto basado en el comercio exterior y logística / Keyla Karina González Martínez -- Tecnologías integradas en gestión sostenible de operadores turísticos en zonas de posconflicto del departamento del meta / Carlos Hernán Cruz Castro; óscar Eduardo Sarmiento Saavedra -- Herramienta online de control de ingresos y facturación: una solución dinámica para las pequeñas y medianas empresas / Esmerlis Camargo Torres; Antonio José González Liñán; Marieth Orcasitas Peñaloza; Yerson Monroy Contreras -- Modelo de cadena productiva dinamizado a través de la educación y las estrategias TIC para el desarrollo regional sostenible en Risaralda / Beatriz Elena Franco Cárdenas; Patricia Henao Montoya; Marco Aurelio Aristizabal Valencia -- Evaluación físico - química de adhesivo de yuca (manihot esculenta) como alternativa comercial para la Orinoquia / Yarithza Molina Caro; Wilfran Hernán Cortes Conde -- Formulaciones nutracéuticas alimenticias para estilos de vida saludables / Daldo Araujo Vidal; Daniel Mendoza Cujia; Maresa Anaya de oro -- Competencias tecnológicas como estrategia formativa en los aprendices de gestión de redes de datos del SENA regional guajira / Carlos Antonio Salas Solano; Alejandro Jesús Osorio Amaya; Alda Pérez Campuzano; Duvan Andrés rondón bravo -- Uso y apropiación del computador como herramienta para las prácticas educativas de los docentes / Alda Pérez Campuzano; Carlos Antonio Salas Solano; Elkin Fuentes Jiménez; Kira Rodríguez Moscote -- El aviturismo como eje transformador de cultura ambiental y desarrollo sustentable / Lina María Gamarra Pineda; Néstor Alejandro Tascón Arias -- Huella ecológica (he), indicador de condición ambiental para evaluar la sostenibilidad en instituciones de educación (ie) / Cristian David Trujillo CardonaPrimera ediciónna169 página