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Combustible and noncombustible notions have evolved with time, along with the associated fire tests by which legislation classifies building materials. New Zealand, Japan, and Europe are just some of the many legislations that have followed this evolution, except for North American regulations, which remain attached to methods dating back to 1944. To better understand this stagnation in North American practices, this document first traces the evolution of Canadian regulations on fire classification of materials. Then, a parallel is drawn with the evolution of reaction to fire tests mandated in the National Building Code of Canada. Finally, this paper will review the current fire classification of materials concerning the combustibility concept based on the Steiner tunnel test and the flame spread rating criteria. The analysis reveals that the relevance of the test and its results are questionable, and the reciprocity between test measurement and its classification does not always coincide. Despite the revisions made through time, the classification of materials based on their fire properties remains distinctly binary. [ABSTRACT FROM AUTHOR]

Reduced reliance on synthetic chemical fertilizers necessarily requires using renewable biomaterial-derived soil organic amendments (SOAs) in agriculture for sustained retention of nutrients through improvement in the soil organic matter (SOM). SOM replenishment through SOAs derived from wasted materials could help in its valorization by furthering the sustainability prospects of agronomic crop production systems. In the current study, compost (CP) and biochar (BC) were derived as SOAs from combustible and compostable fractions of municipal solid waste (MSW) for their potential valorization by adding SOAs as potential sustainable sources of nutrients as a replacement of chemical fertilizers (CF) for sunflower crops cultivated in potted soils. The experimental design included quadruplicated soil application of MSW-derived BC and CP in discrete and combined forms, each in three doses (% w:w), viz., low (L), medium (M), and high (H), i.e., BC-L, BC-M, BC-H; CP-L, CP-M, CP-H; and BC + CP-L, BC + CP-M, BC-CP-H. The results showed that, compared to the control (soil only), the sunflower growth and harvestable yield were significantly greater in BC + CF with a medium dose and were comparable to the growth and yield obtained in soils with CF. Sunflower growth in the discrete SOAs remained less than in the combined SOAs (BC + CP) and was attributed to the comprehensive soil health improvement rendered by the applied SOAs. The soil health improvement factors included SOM, CEC, and concentrations of total and available NPK. The dose-effect comparison of the SOAs showed highly variable trends, i.e., the sunflower growth did not correspond with the increase in dose of the SOAs. It is concluded that the combined application of BC + CP derived from MSW components at a medium dose could act as a potential alternative to CF. The developed approach resulted in MSW valorization, which improved soil health and yielded a better sunflower crop. [ABSTRACT FROM AUTHOR]

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Copyright of Industrial Minerals & Processing / Huagong Kuangwu yu Jiagong is the property of Industrial Minerals & Processing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Water quality, trace gas (SO2, CO2, and NO2), particulate matter (PM 10 as well as PM2.5), and effluent emissions were quantified near cement and oil factories and nearby suburban areas within Delta Nigeria. Results display that ambient air particulate matter PM2.5 varies between 2.1 to 7.9 μg/m3 and VOC (0.013−8.53 μg/m3), while CO and CO2 were 100% and 30% respectively not within regulatory limits, consequently leading to asthma, coughing, and difficulty breathing. Four out of nine sites investigated for noise effects were above WHO stipulated limits. While some parameters such as BOD and COD display critical levels for effluent scrutiny and conductivity, calcium, TDS, total hardness, DO (Dissolved oxygen) and total alkalinity were also above clean water specifications. Wastewater consists of spills and other water effects which produce pollutants such as soluble organic chemicals that deplete dissolved oxygen, anions, volatile materials, and other heavy metals. Based on age, the greatest impact (52%) was seen in ages varying from 0 to 16 while that of the age set 16 to 60 was 45%. Curbing of oil and cement particulate pollutants and requesting a buffer region between the cement and oil depots and neighborhoods, complemented with regulatory enforcement and persistent monitoring, should be a top precedence to the regulatory authority.

Copyright of Ingenius, Revista Ciencia y Tecnología is the property of Universidad Politecnica Salesiana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Reduced reliance on synthetic chemical fertilizers necessarily requires using renewable biomaterial-derived soil organic amendments (SOAs) in agriculture for sustained retention of nutrients through improvement in the soil organic matter (SOM). SOM replenishment through SOAs derived from wasted materials could help in its valorization by furthering the sustainability prospects of agronomic crop production systems. In the current study, compost (CP) and biochar (BC) were derived as SOAs from combustible and compostable fractions of municipal solid waste (MSW) for their potential valorization by adding SOAs as potential sustainable sources of nutrients as a replacement of chemical fertilizers (CF) for sunflower crops cultivated in potted soils. The experimental design included quadruplicated soil application of MSW-derived BC and CP in discrete and combined forms, each in three doses (% w:w), viz., low (L), medium (M), and high (H), i.e., BC-L, BC-M, BC-H; CP-L, CP-M, CP-H; and BC + CP-L, BC + CP-M, BC-CP-H. The results showed that, compared to the control (soil only), the sunflower growth and harvestable yield were significantly greater in BC + CF with a medium dose and were comparable to the growth and yield obtained in soils with CF. Sunflower growth in the discrete SOAs remained less than in the combined SOAs (BC + CP) and was attributed to the comprehensive soil health improvement rendered by the applied SOAs. The soil health improvement factors included SOM, CEC, and concentrations of total and available NPK. The dose-effect comparison of the SOAs showed highly variable trends, i.e., the sunflower growth did not correspond with the increase in dose of the SOAs. It is concluded that the combined application of BC + CP derived from MSW components at a medium dose could act as a potential alternative to CF. The developed approach resulted in MSW valorization, which improved soil health and yielded a better sunflower crop.

El desarrollo de modelos matemáticos han ayudado a explicar comportamiento sociales, económicos y ambientales, para este caso, la construcción de un modelo de combustible de la vegetación del Parque Natural Regional Los Besotes se convierte en fundamental para la toma de decisiones y la gestión del territorio, por lo cual, esta investigación se centró en desarrollarlo mediante imágenes satelitales de la plataforma Landsat 7 ETM+ C2 L1, datos del periodo 2011 a 2020, con el cual se obtuvieron dos modelos de combustibles, resaltando el constituido con los indicadores EVI de Jung, SAVI y ARVI, ya que poseen características atípicas con la morfología del terreno y consideran variables físicas externas en sus fórmulas. Los modelos fueron predichos a una probabilidad inferior a Alpha (p-value < 0,05), lo que indica una excelente predicción de la combustión vegetal.

En los últimos años, el ambiente se ha visto afectado a causa de la contaminación producida por los vehículos. El presente proyecto de investigación tuvo como objetivo determinar la incidencia del aire acondicionado (A/C) en el índice de consumo de combustible vehicular en el cantón Shushufindi, por medio de pruebas reales de tráfico, modo de conducción eficiente y empleo de gasolina extra y súper, para la selección de la mejor alternativa. El estudio se realizó en una ruta de mayor flujo de vehículos, especialmente en la hora normal (9 a. m.) y pico (5 p. m.) que comprende 16.17 km, para ello se utilizó el combustible Extra (85 octanos) y Súper (92 octanos). La toma de datos se ejecutó mediante un sistema OBD2 ELM 327. Los resultados obtenidos en la caracterización del ciclo mixto representativo de 9 a. m. se obtuvo una velocidad máxima de 81 km/h y una velocidad media de 39 km/h en un tiempo de recorrido de 1446 s; mientras que el ciclo mixto de 5 p. m. la velocidad máxima es de 70 km/h y una velocidad media de 37 km/h con un tiempo de recorrido de 1632 s. El menor índice de consumo de combustible se evidenció en el horario normal, sin A/C y combustible extra (T3) siendo sus valores entre 0.0584 – 0.060 (L/km), y en el horario normal, sin A/C y combustible súper (T7) que se encuentran entre 0.0561-0.0585 (L/km).

Copyright of Journal of Indonesian Civil & Environmental Engineering / Jurnal Teknik Sipil & Lingkungan is the property of IPB University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This article updates earlier publications of an ongoing research project on worldwide fire incidents that occurred in tank farms, which store products ranging from low flashpoint materials to crude and heavier hydrocarbons. The incidents and information in the database came from almost 300 sources, including technical reports and news releases. This research supports tank farm hazard identification/risk assessment and the reliability analysis of fire water protection systems (FWS). The research provides valuable insights such as the frequency of tank farm fires, the frequency of boilovers, the frequency of injuries/fatalities, the probability of failure of the FWSs, and the time to extinguish (TtEx) the fires. When the database provides sufficient information, these numbers appear as a function of the stored product. The data also allows plotting TtEx as a function of time for over a century. Additionally, this article illustrates the results of a confidence level analysis of the risk assessment of a distribution terminal that handles low and high‐flashpoint products. [ABSTRACT FROM AUTHOR]

The development of mathematical models have helped to explain social, economic and environmental behavior, for this case, the construction of a fuel model of the vegetation of the Los Besotes Regional Natural Park becomes essential for decision making and land management, therefore, this research focused on developing it through satellite images from the Landsat 7 ETM+ C2 L1 platform, data from the period 2011 to 2020, with which two fuel models were obtained, highlighting the one made up of Jung's EVI, SAVI and ARVI indicators, since they have atypical characteristics with the morphology of the terrain and consider external physical variables in their formulas. The models were predicted at a probability lower than Alpha (p-value < 0.05), indicating an excellent prediction of plant combustion. [ABSTRACT FROM AUTHOR]

Introducción: El aceite de fúsel es un residuo del proceso de rectificación del etanol, compuesto por diferentes alcoholes ligeros donde predomina el alcohol isoamílico y el isobutanol. Objetivo: Realizar una revisión bibliográfica que permita conocer los principales usos del aceite de fúsel en la actualidad. Materiales y Métodos: Se consultan trabajos realizados por diferentes autores que permiten identificar las ventajas del uso del aceite de fúsel como combustible alternativo en motores de combustión interna, para la generación de vapor y para la obtención de ésteres. Resultados y Discusión: El aceite de fúsel como combustible alternativo en motores de combustión interna reduce la densidad, el poder calorífico y el número de cetano de los combustibles modificados. Las mezclas de aceite de fúsel y diésel en estos motores aumentan la presencia de hidrocarburos hasta un 40 % y reduce el contenido de óxidos de nitrógeno en las emisiones de gases. El empleo como combustible en generadores de vapor de las destilerías permite un ahorro de fuel de un 2,12 % en relación al total requerido en el proceso de obtención de alcohol. En la esterificación a partir del isobutanol y el alcohol isoamílico se alcanzan rendimientos molares de 57,48 % y 54,04 % para el acetato de isobutilo y acetato de isoamilo respectivamente, ésteres que son demandados en la industria alimenticia. Conclusiones: El aceite de fúsel tiene amplias utilidades industriales al emplearlo como combustible y como fuente de materia prima para la obtención de productos de alto valor agregado como los ésteres.

Objective: to compare air pollution’s behavior during quarantine in the city of Bogota, in regard to other cities in the world in aspects such as population, area, among others, through a statistical analysis of the concentration data of pollutants PM10, PM2.5 and NO2, for the period from January to July 2020. Materials and methods: 20 cities were selected according to the matrix for the study. Using the BOOTSTRAPPING technique, a correlation matrix and histograms were made for each of the pollutants per phase. For the application of the PCA, the analysis was carried out using MATLAB software, with respect to the averages per phases and change magnitudes. SPSS software was used to normalize the data for the treatment of the variables of interest. Making use of ARIMA and ETS modeling, the data were analyzed longitudinally, the forecast of concentrations with and without quarantine, including the comparison between cities. Results: In the reactivation phase, Bogota presented a significant increase in its pollution levels, especially in PM10. In the differences between the phases before and reactivation, Bogota obtained a lower magnitude in the case of PM2.5, while for NO2 it was more remarkable. Conclusions: In the quarantine, Bogota experienced a significant decrease in the concentration of PM10 and NO2. This was not the case for PM2.5 concentration due to different temporary events (fires and particulate matter transportation). [ABSTRACT FROM AUTHOR]

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Purpose: develop an engineering method for determining sulfur in mineral impurities to predict the hazardous properties of mine seams in mining operations. Methodology: The research methodology and the development of the method are based on a close correlation dependence of the sulfur content in the combustible part of the fuel on the total sulfur for coals of almost all mine seams of the Donetsk and Lvov-Volyn basins. The ratios between the organic mass and mineral impurities are characterized by the yield of ash. The ratio of ash content of reservoir and enriched samples, as well as information about the content of total sulfur and sulfur in the combustible part, make it possible to estimate the sulfur content in mineral impurities by calculation. All the initial data necessary for the development of the method were established experimentally by standard methods over several decades and are given in the reference and regulatory documents on the consumer qualities of coals. Results: The percentage of total sulfur for the entire set of considered coal seams can either exceed the sulfur content in the combustible part of the fuel or vice versa. The difference between the content of total sulfur and its presence in the combustible part of the fuel is, in the first approximation, a criterion for assessing the possible sulfur content in the conditionally non-combustible part of the fuel. Negative values of the criterion indicate the predominant sulfur content in the combustible part, and positive values, in the conditionally non-combustible (mineral) impurities. Based on the available initial experimental data on the content of total sulfur in the combustible part of the fuel, the yield of ash from reservoir and enriched samples, dependencies are proposed for calculating the sulfur content in conditionally non-combustible components. Between the calculated values of the sulfur content in the conditionally non-combustible part and the proposed criterion, correlations are considered for seven sets of coal seams. The formation of the populations was done taking into account the possible influence of enrichment processes and positive or negative values of the proposed criterion. Based on the analysis of empirical dependences of the considered sets of coal seams, the necessary conditions were established for obtaining the most reliable results of the calculated determination of sulfur in conditionally non-combustible (mineral) impurities of fossil coals. Scientific novelty: For the first time, empirical dependences of the sulfur content in conditionally non-combustible (mineral) impurities were established according to the proposed criterion. Practical value: The results are necessary to improve the regulatory framework for the safety of mining operations in terms of predicting the manifestation of hazardous properties of coal seams due to the presence of sulfur varieties.

Actualmente, la matriz energética en Bolivia depende en gran medida de los combustibles fósiles, hecho que conlleva a problemas económicos especialmente considerando que la producción de gasolina en Bolivia no cubre la demanda del mercado interno y que se tiene que recurrir a la importación a precios elevados. Además, la transición hacia una matriz energética más limpia también puede impulsar la innovación y desarrollo de nuevas tecnologías y soluciones para abordar el cambio climático y proteger el medio ambiente, aspectos que son promovidos por las Naciones Unidas con los Objetivos de Desarrollo Sostenible 7 y 11. En este sentido, este trabajo se centra en el estado del arte de la influencia de mezclas etanol-gasolina en el desempeño de motores de combustión interna, con el objetivo de tener un punto de partida para un posible uso de estas mezclas en el país y así reducir el consumo de gasolina. Inicialmente, se realizó un estudio de las propiedades fisicoquímicas de diferentes mezclas de combustible gasolina-etanol encontrados en la literatura. Después, se analizó el efecto del porcentaje de etanol en la mezcla en parámetros que definen el desempeño de un motor como: la eficiencia térmica, el consumo especifico de combustible al freno, la máxima torsión de frenado y el consumo especifico de combustible. Finalmente, se realizó un análisis exhaustivo de la literatura concerniente a efectos de la mezcla etanol-gasolina en el impacto al medio ambiente y efectos negativos al motor.

This article presents several insights from research of fire incident data from tank farms from around the world, which store products ranging from low flashpoint materials to crude and heavier hydrocarbons. The incidents and information in the database came from over 130 mostly publicly available sources, including technical and news reports. Updating of the database takes place when new studies require analysis of previous incidents. The database contained 595 fire incidents at the time of preparation of this article, and this research has already supported the analysis of the reliability of fire water protection system, hazard identification, and risk assessment for several tank farms. The research provided valuable insights regarding the frequency of tank farm fires, the frequency of boilovers, the frequency of injuries/fatalities, the expected numbers of injuries/fatalities per incident, the frequency of dike fires, the probability of failure of the fire water system, the time to extinguish (TtEx) the fires, the ignition source, and the types of tank roofs. When the database provided sufficient information, these numbers appear as a function of the material or product. The data also allowed plotting TtEx as a function of the (a) time for over a century, (b) tank diameter, and (c) number of tanks on fire. [ABSTRACT FROM AUTHOR]

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En Costa Rica existe un vacío en la creación de políticas para la gestión eficiente del consumo de recursos y del desarrollo de estadísticas de consumo de energía, que permita medir el desempeño de la sostenibilidad en la construcción. Por lo tanto, se realizó una investigación con el propósito de reconocer el estado de desarrollo de control y la gestión eficiente de recursos de consumo energético en la construcción a nivel internacional y nacional. Posteriormente, se desarrollaron procesos y herramientas para la creación de una metodología, con el fin de generar una primera aproximación para estimar y registrar el consumo energético de edificaciones verticales en construcción y definir estadísticas en desempeño. Esta se aplicó en dos proyectos de edificios verticales durante la construcción de obra gris, con el fin de analizar la gestión del consumo de recursos. Además, esta metodología propuesta obtuvo un alto grado de aceptación por parte de un comité de validación, la cual fue considerada válida para la estimación y registro de estadísticas de sostenibilidad a lo largo del desempeño en el proyecto, lo cual ayuda a tener un control de los consumos de recursos.

Abstract Background Cigarette smoking is three times more prevalent among youth experiencing homelessness compared with the general population. Co-use of tobacco and marijuana is also common. The aim of this study is to characterize tobacco and marijuana use among youth experiencing homelessness who use combustible tobacco in a Midwestern city to inform smoking cessation intervention. Methods This study included 96 youth (ages 14–24 years; 52% male, 39% female, 5% transgender/non-binary) attending a homeless drop-in center who had used at least one combustible tobacco product in the past week. We assessed past-month use of tobacco products and marijuana, other product use characteristics (e.g., frequency, brand and flavor), and psychosocial predictors of more frequent (i.e., daily) use of combustible tobacco and marijuana. Results Most youth experiencing homelessness with past-week combustible tobacco use had used cigarettes (n = 85, 88.5%), cigars (n = 89, 92.7%), and marijuana (n = 82, 85.4%) in the past month. One-third (n = 34) used electronic vapor products (EVPs), 19.8% (n = 19) smoked hookah, and 11.5% (n = 11) used smokeless tobacco (ST). Most marijuana users co-administered with tobacco (n = 67, 69.8%). Daily combustible tobacco smoking was associated with having a child and smoking out of boredom/habit. Daily marijuana use was associated with using substances to cope with one’s housing situation. Newport (n = 66, 72.5%) and Black & Mild (n = 48, 51.1%) were the most popular brands of cigarettes and cigars among ever users. Most non-combustible tobacco ever users reported not having a usual brand (EVPs: n = 51, 73.9%; ST: n = 16, 57.1%). Cigar smokers reported the most varied selection of flavors. Conclusions Young combustible tobacco users experiencing homelessness engage in high-risk use patterns, including poly-tobacco use, co-use of tobacco with marijuana, and frequent combustible product use. Interventions that consider the full context of tobacco and marijuana use are needed to support smoking cessation in this population.

Introduction: There is an established link between tobacco use and adverse oral health outcomes. However, there is a paucity of research exploring the effect of various tobacco products on clinically diagnosed adverse oral health outcomes.Methods: Data were pooled from three cycles of the National Health and Nutrition Examination Survey: 2009-2010; 2011-2012; and 2013-2014 (n = 11,453). Multivariable logistic regressions examined the associations between periodontitis and dental caries with the type of tobacco product used (combustible, non-combustible or both).Results: Overall, 42.3% of the study sample had any periodontitis, 7.8% had severe periodontitis and 21.7% had dental caries. There was a higher prevalence of periodontitis and caries among combustible tobacco users than non-combustible tobacco use; 62.1% of combustible tobacco smokers had any periodontitis, 17.1% had severe periodontitis, while 39.4% of adults with dental caries were dual users. Compared to non-smokers, combustible tobacco use increased the odds of any periodontitis (adjusted odds ratio [aOR] 2.81, 95% confidence interval [CI] 2.28, 3.45) and severe periodontitis (aOR 2.62, 95% CI 1.90, 3.61). Compared to non-smokers, both combustible tobacco (aOR 2.11, 95% CI 1.61, 2.76) and non-combustible tobacco use (aOR 2.09, 95% CI 1.19, 3.66) increased the odds of dental caries.Discussion and Conclusions: In this study of US adults, combustible tobacco use was associated with periodontitis and dental caries, while non-combustible tobacco use was associated with dental caries. In addition to conducting extensive oral health screening among all smokers, oral health-care providers should counsel smokers on the need for smoking cessation. [ABSTRACT FROM AUTHOR]

Introduction: Fusel oil is a residue from the ethanol rectification process, composed of different light alcohols where isoamyl alcohol and isobutanol predominate. Objective: To carry out a literature review that allows us to know the main uses of fusel oil at present. Materials and Methods: Works carried out by different authors are consulted to identify the advantages of the use of fusel oil as an alternative fuel in internal combustion engines, for steam generation and for obtaining esters. Results and Discussion: Fusel oil as an alternative fuel in internal combustion engines reduces the density, calorific value and cetane number of the modified fuels. The blends of fusel oil and diesel in these engines increase the presence of hydrocarbons up to 40 % and reduce the content of nitrogen oxides in gas emissions. Its use as fuel in steam generators in distilleries allows a fuel oil saving of 2.12 % in relation to the total required in the process of obtaining alcohol. In the esterification from isobutanol and isoamyl alcohol, molar yields of 57.48 % and 54.04 % are achieved for isobutyl acetate and isoamyl acetate respectively, esters that are demanded in the food industry. Conclusions: Fusel oil has wide industrial utilities by employing it as fuel and as a source of raw material for obtaining high value-added products such as esters. [ABSTRACT FROM AUTHOR]

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La temperatura de fusión de las cenizas de un combustible es un parámetro crítico ligado a la calidad del mismo y resulta imprescindible su conocimiento para valorar un posible comportamiento de aquellas en el interior del hogar de una caldera de vapor. Este parámetro es una característica del estado físico que adquieren las cenizas de una biomasa utilizada como combustible cuando se las somete a un calentamiento progresivo bajo ciertas condiciones y es función del tipo de biomasa, la composición química y el tipo de atmósfera circundante. Es una medida del potencial que tienen los materiales combustibles para formar escorias y que, finalmente, generan obturaciones e incrustaciones indeseables sobre las superficies interiores del hogar de las calderas, entre ellas los tubos de refrigeración de la cámara de combustión y paredes radiantes, los pasajes de aire en grillas, entre los tubos del sobrecalentador y el haz convectivo, etc. El presente trabajo muestra los resultados del análisis de la fusibilidad de las cenizas de bagazo y residuos agrícolas de cosecha (RAC) de la variedad LCP-85-384 de caña de azúcar de Tucumán - Argentina, según norma ASTM D 1857, determinados con un equipo analizador de fusibilidad de cenizas automatizado que trabaja bajo atmósferas controladas. Se analizaron 20 muestras de bagazos y 20 muestras de RAC, las cuales se procesaron en el Laboratorio de Ensayos y Mediciones Industriales (LEMI) de la Estación Experimental Agroindustrial Obispo Colombres (EEAOC), operando en atmósferas oxidante y reductora. Los resultados indican que las temperaturas promedio de inicio de la fusión (DT) para cenizas de bagazo se encuentran dentro del mismo orden magnitud y no muestran diferencias significativas cuando se las someten a un calentamiento en atmósferas oxidantes y/o reductoras. Un comportamiento similar se observó con las cenizas de RAC. Además, se observó que las temperaturas DT resultaron sensiblemente menores en el RAC respecto a la del bagazo para las atmósferas analizadas (1054,4 ºC vs. 1081,1 ºC, para atmósfera reductora; y de 1058,0 ºC vs. 1110,0 ºC para atmósfera oxidante, respectivamente).

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In the research carried out, the objective is to determine the energy and operating costs of the assembly formed with the tractor MF 275, the forage corn harvester KUHN MC 90S TWIN, and a trailer, in the farm "La Ceibana", state Trujillo, Venezuela. In this work the total energy costs of the agricultural operation amounted to 804,77 MJ/h; the energy cost component of the energy required in the fuel represented 600,37 MJ/h, the highest value. being 74,6% of the total energy costs, a value very significant, and the other 25,39% corresponds to the energy required for repair and maintenance with 87,98 MJ/h (10,93%); materials, manufacturing and transport with 68,2 MJ/h (8,47%), lubricants 30,02 MJ/h (3,73%), labor force 18., MJ/h (2,26%) and finally, the total energy costs per unit of mass harvested amounted to 758,25 MJ/t. On the other hand, the total direct operating costs of the whole for the harvest of forage corn amounted to 1 316, 46 Bs/h. The operating cost component that represented the highest value was reflected in maintenance and repairs with 1 047,2 Bs/h, representing 79,54% of the total operating costs, with around 20% distributed between the salary of service personnel 156,25 Bs/h (11,86%), the amortization of machinery 112,13 Bs/h (8,51%) and fuel 0,88 Bs/h (0,0006% ); operating costs per unit of harvested mass 787,4 Bs/t and finally the costs per unit of total energy required in the forage harvest process reach 1,629 Bs/MJ. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Scientific & Technical Applications / Revista de Aplicación Científica & Técnica is the property of ECORFAN-Mexico S.C. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Este artículo describe la distribución de las amenazas tecnológicas en el cantón La Unión de Cartago y muestra los radios de máximo alcance por eventuales explosiones en gasolineras. En las industrias, gasolineras y el poliducto de la Refinadora Costarricense de Petróleo (RECOPE) podrían suscitarse incidentes tecnológicos lo que demanda estudios para conocer su capacidad destructiva. El trabajo da a conocer el potencial de los incidentes tecnológicos en el cantón La Unión y servirá para manejar más eficientemente estos peligros tecnológicos. Se utilizó una relación de linealidad y proporcionalidad con datos del Servicio Geológico Mexicano para estimar el alcance de explosiones en gasolineras. Con el fin de conocer la extensión de las fugas de gases industriales se utilizó como guía un estudio sobre amenazas químico-tecnológicas de la Gran Área Metropolitana (GAM) y se revisó referencias sobre incidentes ocurridos previamente. Un estudio de campo, para verificar la presencia de asentamientos humanos cerca del poliducto, y revisión bibliográfica permitieron tener una idea del potencial de amenaza del poliducto. Los resultados indican que los radios de máximo peligro asociados a explosiones de gasolineras en La Unión varían entre 6,85 y 13,08 metros y que la fuga de gases puede tener impacto en áreas de un radio cercano a los 10 km.

Background: Cigarette smoking is three times more prevalent among youth experiencing homelessness compared with the general population. Co-use of tobacco and marijuana is also common. The aim of this study is to characterize tobacco and marijuana use among youth experiencing homelessness who use combustible tobacco in a Midwestern city to inform smoking cessation intervention.Methods: This study included 96 youth (ages 14-24 years; 52% male, 39% female, 5% transgender/non-binary) attending a homeless drop-in center who had used at least one combustible tobacco product in the past week. We assessed past-month use of tobacco products and marijuana, other product use characteristics (e.g., frequency, brand and flavor), and psychosocial predictors of more frequent (i.e., daily) use of combustible tobacco and marijuana.Results: Most youth experiencing homelessness with past-week combustible tobacco use had used cigarettes (n = 85, 88.5%), cigars (n = 89, 92.7%), and marijuana (n = 82, 85.4%) in the past month. One-third (n = 34) used electronic vapor products (EVPs), 19.8% (n = 19) smoked hookah, and 11.5% (n = 11) used smokeless tobacco (ST). Most marijuana users co-administered with tobacco (n = 67, 69.8%). Daily combustible tobacco smoking was associated with having a child and smoking out of boredom/habit. Daily marijuana use was associated with using substances to cope with one's housing situation. Newport (n = 66, 72.5%) and Black & Mild (n = 48, 51.1%) were the most popular brands of cigarettes and cigars among ever users. Most non-combustible tobacco ever users reported not having a usual brand (EVPs: n = 51, 73.9%; ST: n = 16, 57.1%). Cigar smokers reported the most varied selection of flavors.Conclusions: Young combustible tobacco users experiencing homelessness engage in high-risk use patterns, including poly-tobacco use, co-use of tobacco with marijuana, and frequent combustible product use. Interventions that consider the full context of tobacco and marijuana use are needed to support smoking cessation in this population. [ABSTRACT FROM AUTHOR]

The main disadvantage of using biodiesel is its price, which is due to high costs of raw material and oil conditioning to obtain biodiesel by conventional transesterification, which prevents it from competing with fossil fuels. An alternative method was investigated to obtain biodiesel by in-situ transesterification or reactive extraction (RE) from Jatropha Curcas L. seeds. This alternative process seeks to reduce stages in the production process, and thus, reduce operational costs with respect to the conventional method. The influence of temperature, catalyst mass concentration (g NaOH/g oil), and methanol to oil molar ratio, in order to maximize yield and FAME concentration of biodiesel obtained, was determined through a central composite design (DCC) with response surface methodology. The most appropriate conditions to obtain biodiesel by in-situ transesterification occur at 44°C, with a mass concentration of catalyst 1,2 g NaOH/100 g oil, and with a methanol to molar ratio of 135:1 with the presence of hexane, keeping constant stirring speed (635 rpm) and reaction time (3h). In these conditions, a yield of 71,99% w/w (g biodiesel/g oil) and a FAME content of 90,36% w/w (g FAME/g biodiesel) were reached. The results of this study provide an alternative process for obtaining biodiesel without the need of extraction and pretreatment stages employed in the traditional method, in addition to reducing excess washes in the conventional process, which increase process costs and environmental impact. [ABSTRACT FROM AUTHOR]

For the development of this research, sludge from the fur process was used in the production of leathers that are treated in the RWTPI of the tanners association of La María. As an alternative to the final disposal of these sludges in a sanitary landfill, it is proposed to use them as a source of biogas generation, for which the parameters of organic matter were quantified as volatile TS calcined at 550 ° C / 6 hours, oxidizable organic matter such as COD, % Moisture and amount of methane generated in ml using the Mariotte bottle technique; the process was carried out with the use of 3 bio-inputs (Indigo Biowish, Biorenova), determining the optimal time to maximize methane generation. [ABSTRACT FROM AUTHOR]

The purpose of the research was to design a methodological guide for the preparation of the cash flow statement by the direct method under the IFRS for SMEs that provides information for decision-making in the fuel companies of the city of Cuenca. it was developed under a descriptive non-experimental type. 62.5% of administrators (see figure 3) do not analyze the cash flow statement to make decisions. It was found that the majority of the administrators of the service stations of the city of Cuenca do not make their decisions based on the cash flow statement if they do not support their decisions in the income statement, which shows the ignorance of the information that provides the cash flow statement for the proper management of financial resources.

Fire protection of timber structures and finishing structural materials is actual due to the high combustibility of these materials. The technical characteristics for protected timber structures in case of fire, determined by the single burning item test (SBI), are considered in the paper. Nine thin-layered lacquers and paints fire protections, which were differed by the type of fire resistance and chemical contents, were analyzed. The timber specimens treated by such fire protections as the paints, impregnations, lacquers and water glass were tested by SBI method. It was shown, that the lacquer on the base of the acryl resin has a significant influence on the fire growth rate indices FIGRA and smoke growth rate SMOGRA on the initial stage of combustion (FIGRA – 2948.78 W/s, SMOGRA – 101.28 m2/s2). Traditional fire protection by the water glass shows the high fire growth rate indices FIGRA (268.63 W/s) and total smoke production TSP600s (163.13 m2). The low levels of the both values did not confirm a classic consideration of the water glass as effective fire protection of timber members. Type of timber base and assembling method (with or without air gap) has a significant influence on the effectiveness of fire protection. Analogous results obtained for the intumescent paint and two types of lacquers. The modern water impregnations that contains phosphoric acids characterized by the low expenditure (mean value 250 g/m2) and low values of smoke growth rate and total smoke production in 3MJ and 33 m2, correspondingly. These impregnations provides a class Bs1d0 of fire protection by the European classification.

Una desventaja del uso de biodiésel es su precio, debido a los altos costos de la materia prima y al acondicionamiento del aceite requerido para obtenerlo por medio de una transesterificación tradicional, lo que le impide alcanzar precios más accesibles y dificulta su competitividad con el diésel de petróleo. Por esta razón, se investigó una alternativa para la obtención de biodiésel mediante transesterificación in situ o extracción reactiva (ER) a partir de semillas de Jatropha curcas L. Con esta alternativa en auge, que no compite con el mercado alimenticio, se busca reducir etapas en el proceso de producción y así disminuir costos de operación respecto al método y aceites convencionales. Se determinó la influencia de la temperatura, concentración másica de catalizador (g NaOH/g aceite) y relación molar metanol:aceite, con el fin de maximizar el rendimiento y la concentración de FAME del biodiésel obtenido, mediante un diseño experimental central compuesto (DCC) con método de superficie de respuesta. Se encontró que las condiciones más apropiadas para la obtención de biodiésel por transesterificación in situ fueron una temperatura de reacción de 44 °C, con una concentración másica de catalizador respecto al aceite de 1,2 g NaOH/100 g aceite y una relación molar metanol:aceite de 135:1, con presencia de hexano, manteniendo constantes la velocidad de agitación (635 rpm) y el tiempo de reacción (3 h). En estas condiciones, se alcanza un rendimiento de 71,99 % p/p (g biodiésel/g aceite) y un contenido de FAME del 90,36 % p/p (g FAME/g biodiésel). Los resultados de este estudio establecen las bases para una alternativa al proceso tradicional que no necesita las etapas de extracción y pretratamiento de los aceites utilizados como materia prima, además de disminuir los lavados necesarios en el proceso convencional, que incrementan los costos de dicho proceso industrial e impactan en el medioambiente.

Oil and its derivatives are very important goods in the world, not only because of their huge use but also because the consequences of that use. The literature has plenty of works with economic analysis of the use of oil. Having available a huge amount of data, we propose an innovative approach: based on daily information of sales in a gas station since 2001 to 2018, we make a seasonality analysis of those sales. In separate analysis, using information of the both existing shifts, of the week day and of the month, we conclude that seasonality in sales is significant. This is an important information for firm managers, which could use this information to better define their strategies. [ABSTRACT FROM AUTHOR]

The present research study aims to develop a novel methodology for estimating the VKT (Vehicle Kilometers Traveled) indicator and the energy consumption according to road transport type. Calculations are made for the Province of Loja (Ecuador) for the year 2014 by using an OLADE (Latin American Energy Organization) energy balance method. This is combined with a model similar to the Hardy Cross hydraulic flow systems solution with linear equations. The transportation system is represented as an energy balance and the inputs are: total fleet and vehicle type, specific average consumption for each vehicle type, and global fuel sales. The results show that there is a 2% variation between calculated consumed energy and total dispatched energy. The total energy used is 1,123,198 BEP, of which 24.65% is for passenger transport and 66.18% for cargo transport. It is concluded that the proposed methodology is appropriate, applicable nation-wide, and replicable in other provinces. [ABSTRACT FROM AUTHOR]

Copyright of Revista Didasc@lia: Didáctica y Educación is the property of Universitaria de Las Tunas, Centro de Estudios de Didactica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

El autor informa sobre sus experimentos con 55 maderas pertenecientes a especies de la flora tucumana. Para cada madera se da el poder calorífico superior e inferior del núcleo, la albura y la corteza, valores que se determinaron con la ayuda del calorímetro Mahler-Kröker. También se calcularon los valores caloríficos prácticos y los correspondientes valores equivalentes de una tonelada de gasóleo o hulla en cada una de las maderas examinadas.

The Grenfell Tower fire has brought the regulatory system that permitted combustible materials on high-rise buildings in England into question. At the heart of that system is the BS 8414 test, and the BR 135 criteria used to demonstrate compliance with the Building Regulations. The test is empirical and the criteria arbitrary: there is no scientific link between test performance and how a building will perform in the event of a fire; nor any detailed analysis of why fires spread through façade systems which have passed the test. Following the Grenfell tragedy, the UK government commissioned a series of tests on Grenfell Tower-type facades, using BS 8414. This paper critically analyses BS 8414, the BR 135 criteria and the government tests. It shows that important aspects of the standard are poorly defined: the heat flux imposed on the façade is not measured and the fire load can vary by at least a factor of 2; the ambient ventilation has a significant impact on the thermal attack but is not adequately controlled; judicious location of the cavity barriers can confer compliance or failure on a façade system. As the vehicle for allowing combustible products on tall buildings, the test does not specify the extent of cavity barrier deployment, while ignoring features present in real buildings, such as windows, vents or other openings, despite a test rig height of more than 8 m. There is no restriction on debris, or molten or burning droplets falling from the façade during the test. The BR 135 criteria only specify that the test must run for the full 60 min duration without flames reaching the top, and the temperature rise at thermocouples 5 m above the fire chamber must only remain below 600°C for the first 15 min. It is unclear how the fire safety of the occupants behind the façade system can be ensured, when the criteria specify such a high temperature for such a short period, so early in the test. There is no direct connection between the façade system in the test and the actual façade system the results deem compliant. Worse, "desktop studies", using large-scale test data, have been allowed to confer compliance on systems which have never been subject to the test. The UK government tests used heavy-duty welded aluminium "window pods", preventing flames from entering the cavity within the façade. They also used a disproportionately large number of vertical and horizontal cavity barriers of a higher specification than required by statutory guidance. These aids to meeting the criteria are not proscribed by BS 8414-1 but are not commonly found in actual rainscreen system designs. [ABSTRACT FROM AUTHOR]

The objective of the research was to develop a procedure to evaluate the maintenance function implemented in a fleet of fuel transport vehicles by road. The Hyundai brand equipment was taken as a sample, analyzing the existing information from the year 2017. Statistical methods, analysis and synthesis, theoretical modeling, systemic analysis of the maintenance process, of vehicles, systems and components were used; as well as reliability indicators. The systemic analysis and stratified evaluation of the results made it possible to determine the critical systems and components, as well as to base the most effective technical actions, which were incorporated into the maintenance system, as well as the demand for parts, pieces and supplies, as part of the own procedure. The results obtained show the effectiveness of the proposed procedure. [ABSTRACT FROM AUTHOR]

El transporte terrestre, en la actualidad, es una necesidad; su funcionamiento es generado principalmente por el uso de combustibles fósiles que, por medio de una combustión incompleta en los vehículos automotores, producen la energía necesaria para su movimiento así como la emisión de monóxido de carbono, dióxido de carbono, óxidos de nitrógeno, óxidos de azufre y compuestos orgánicos volátiles que, al entrar en contacto con el ser humano, son consideradas las principales causas de las enfermedades respiratorias, cancerígenas y sanguíneas. En este sentido, en el presente artículo se realiza un compilado de las investigaciones efectuadas a nivel global, que permitan determinar la relación entre la combustión asociada con el funcionamiento del transporte terrestre y los niveles de contaminación que afectan la calidad del aire y la salud de las personas. De acuerdo con las investigaciones a nivel global, se encuentra que el material particulado (PST, PM10 y PM2.5) es el principal contaminante relacionado con la influencia del transporte terrestre en la salud pública. Land transportation is a necessity today, whose operation is generated mainly by the use of fossil fuels, which through incomplete combustion in motor vehicles generate the energy necessary for their movement, as well as the emission of carbon monoxide, carbon dioxide, nitrogen oxides, sulfur oxides and volatile organic compounds, which in contact with humans are considered the main causes of respiratory, carcinogenic and blood diseases. In this sense, in this article a compilation of the investigations carried out at a global level is made, which will determine the relationship between the combustion associated with the operation of land transport and the levels of pollution that check air quality and public health. According to global research, it is found that particulate matter (PST, PM10 and PM2.5) is the main pollutant that is related to the influence of land transport on public health. [ABSTRACT FROM AUTHOR]

Abstract A catalytic combustible type single-chip micro gas sensor was fabricated by MEMS technology and responses with input powers and methane and hydrogen gas concentrations were characterized. The ranges of responses at Pt thickness of 450 nm and input power of 128 mW were 1.076–2.433 mV for methane concentrations of 2315–5787 ppm, and 0.965–2.514 mV for hydrogen concentrations of 282–706 ppm, respectively. The ranges of responses at Pt thickness of 150 nm and input power of 112 mW were 0.192–0.438 mV for methane concentrations of 2315–5787 ppm and 0.949 mV to 2.496 ppm for hydrogen concentrations of 282–706 ppm, respectively. The responses to H2 concentration ratios were 3.65 mV/103 ppm for a micro gas sensor with a 450 nm thick heater and 3.81 mV/103 ppm for a micro gas sensor with a 150 nm thick heater. But in the case of methane gas response, the response to concentration ratios of the micro gas sensor using the 150 nm thick Pt heater was remarkably different from the case of the 450 nm thick Pt heater. The ratios for CH4 were 3.51 mV/104 ppm for the micro gas sensor with a 450 nm thick heater and 0.6 mV/104 ppm for the micro gas sensor with a 150 nm thick heater, respectively. From these results, the micro gas sensor that has the thicker heater with a thickness of 450 nm showed higher sensitivity to methane gas than the micro gas sensor with a thinner heater with a thickness of 150 nm.

La biomasa como fuente de energía renovable puede sustituir algunas de las demandas de energías del mundo que actualmente satisfacen los combustibles fósiles. Por ello, el estudio de las propiedades físico químicas y energéticas de estas resulta fundamental a la hora de evaluar su posible utilización como combustible de calderas de vapor. El contenido de sílice total (%SiO2) en las cenizas de una biomasa representa la mayor proporción del material inerte que constituye la misma y que podría generar problemas de corrosión por erosión y formación de escorias durante el proceso de combustión en el interior del hogar de un generador de vapor. La industria azucarera de Tucumán cuenta con una importante cantidad de biomasa que podría utilizarse con fines energéticos; por ejemplo, los residuos de cosecha de la caña de azúcar (RAC). Por ello resulta necesario evaluar el contenido de %SiO2 en este material. Se ha determinado el contenido de %SiO2 siguiendo el método gravimétrico indicado en la norma ASTM E 887-88. Se trabajó con 33 muestras de RAC recolectadas de diferentes campos cañeros de Tucumán. Se encontró un contenido de %SiO2 en un rango entre 37,90% y 70,20%, con un promedio de 57,66% y un coeficiente de variación (CV%) de 15,41%. Para medir la exactitud del método empleado se estudió la recuperación porcentual (%R) de %SiO2, la misma se encontró en un rango entre 80,76% a 99,91%, con un valor promedio de 88,48% y un (CV%) de 6,64.

In this research it was studied the effect of the type of catalyst, the reaction temperature and the catalyst/ paraffins weight ratio in the transformation of paraffins waste obtained from the pyrolysis of plastics by catalytic cracking. It was chosen the Zeolite Y and Zeolite ZSM-5 as catalysts, the catalyst/paraffin weight ratios of 0.4:1 and 0.20:1 and the reaction temperatures of 400˚C and 440˚C. The catalytic cracking reaction of the paraffins was carried out in a fixed bed reactor. By the statistical analysis it was determined that the type of catalyst has the most outstanding effect, thus with the Zeolite ZSM-5 an average yield of 27.43% was reached. In contrast, with the Zeolite Y was obtained a 13.10%. In addition, it was found that the yield increased by 1.2% when a temperature of 400 ° C was used compared to 440°C. The catalyst/paraffin weight ratio does not significantly affect the yield. According to the analyzes performed by gas chromatography to the liquid reaction products, it would be expected that through this process products like diesel, Jet A-1 aviation fuel and gasoline could be obtained. [ABSTRACT FROM AUTHOR]