12 research outputs found
Análise da precarização e intensificação do trabalho docente no Instituto Federal de Pernambuco
O principal objetivo da pesquisa foi analisar as condições de precarização e intensificação do trabalho docente no Instituto Federal de Pernambuco. Foram utilizados como metodologia o levantamento bibliográfico e a análise de dados primários a partir dos questionários respondidos eletronicamente pelos docentes. A reestruturação da Rede Federal de Educação e a criação dos novos regimentos legais e normativos impactaram o exercÃcio docente, e com isso, estabelecendo uma nova cultura institucional
Evaluation of the performance of bio-oil obtained through pyrolysis of coffee waste
Bio-oils are a complex blend of organic compounds formed by fragmentation of the structures present in biomass after undergoing a thermal process known as pyrolysis. Coffee waste is an organic residue discarded in large quantities in Brazil. This work aimed to evaluate some chemical and physicochemical characteristics of this oil, to seek economically viable uses for the product. Five pyrolysis procedures were employed and an average bio-oil yield of 18% was obtained. The oil was subjected to tests such as infrared, pour point and ash content. Infrared spectroscopy revealed an intense aliphatic character of the structure, which also had considerable presence of oxygen due to the presence of functional groups such as carbonylates, carboxylates, esters, ketones, amides and ether, as well as aromatics. The pour point determined for the bio-oil was 20° C and the ash content was less than 1%.
Morpho-physiological responses of Bos indicus, Bos taurus and crossbred weaned heifers to seasonal variations
Animals kept in extensive production systems are constantly exposed to the effects of climatic aspects, which could favour thermal discomfort, decreasing productive and reproductive performances. Utilisation of Bos taurus crosses with Bos indicus animals is increasing in the tropics aimed at improving production and it is now well known how these animals respond in such environment. The objective was to characterize the morpho-physiological thermoregulation responses of weaned heifers from four different genetic groups to infer regarding the different degrees of adaptation to heat under tropical conditions Forty-eight, pasture-kept, 6-month-old, weaned heifers from four distinct genetic groups: (1) Nellore; (2) Senepol; (3) Angus x Nellore; and, (4) ¼ Brahman x ¼ Nellore x ½ Senepol (Tri-cross) were evaluated. Skin, hair coat and rectal temperatures; sweating rate; respiratory and heart rates; visual analysis of hair and hair coat colour; hair coat temperature and thickness; and length, diameter, density and number of hairs were evaluated. In addition, the temperature-humidity index, black-globe temperature and humidity index, and radiant thermal load were determined. Angus x Nellore animals presented the lowest (P=0.008) respiratory rate. Rectal temperature did differ (P=0.001) between seasons. Angus x Nellore heifers showed the greatest (P=0.001) values for the morphological measures in the evaluated months, coinciding with thermal comfort indexes above those considered comfortable for cattle.  Nellore (Bos indicus), Brahman x Nellore x Senepol, and Senepol (B. taurus) present the best adaptive traits in savanna. The utilisation of B. indicus animals or adapted breed confers desirable morphological characteristics for the tropical environment. Beef cattle kept in extensive systems are constantly exposed to the effects of the climate. In tropical and intertropical regions, the reproductive management of Bos taurus animals with B. indicus animals is an alternative for zootechnical improvement. The objective was to evaluate morphophysiological characteristics of heat adaptation of beef heifers on pasture. For this, fifty-four animals from four distinct genetic groups: (1) Nellore, (2) Senepol, (3) Angus x Nellore and (4) ¼ Brahman x ¼ Nellore x ½ Senepol (Tri-cross), with six months-old, were evaluated during the summer and autumn seasons of 2016. The morphological characteristics of the coat (length, diameter, thickness, density and number of hairs and coat color) and physiological (skin, hair and rectal temperature; sweat rate; respiratory and heart rate) were evaluated. The environment was evaluated using the temperature and humidity index, black globe temperature, humidity index and radiation thermal load. We observed that the production environment presented thermal discomfort for the animals. Thus, the animals’ rectal temperature differed between seasons. All groups studied showed some adaptive characteristic to the tropical environment. Angus x Nellore heifers had the highest values for the morphological measures in the months evaluated, coinciding with thermal comfort indexes above those considered comfortable for cattle and the lowest value of respiratory rate when compared between the crossing. In conclusion, all genetic groups have at least three adaptive characteristics to the tropical environment when analyzing the physiological responses
Estudo de fatores que influenciam o cálculo de incerteza da medição de atenuação em lÃquidos
Incerteza é um parâmetro metrológico definido e inerente a qualquer experimento cientÃfico. Determinar, quantificar e combinar as incertezas melhora o padrão de qualidade e a confiabilidade metrológica dos resultados obtidos. Neste trabalho, a incerteza da medição de atenuação de lÃquidos foi estudada com o objetivo de se identificar os principais parâmetros que influenciam nesta incerteza. Para medir a atenuação utilizou-se o método ultrassônico de transmissão => recepção. Portanto, para cada frequência estudada, empregou-se um par de transdutores de mesma frequência nominal de ressonância. Foram utilizados 4 transdutores e 9 pontos de frequências variando entre 1.0 MHz e 5.0 MHz. Para o arranjo experimental proposto, foram encontradas incertezas combinadas inferiores a 1% em todos os casos
Use of biochar obtained from coffee grounds as adsorbent of dyes and solid biofuel
Brazil is the world's largest coffee producer and the second largest consumer. In 2016, the coffee crop was one of the largest in the country's history. One of the main residues of the coffee industry is coffee grounds. They are a daily waste in almost all residences, shops, bars and restaurants. The high production ends up generating an accumulation of waste due to the low processing capacity of this material. Thus, this work had the objective of finding alternative uses for this waste, to add value through the production of solid biofuel and activated biochar to remove contaminants. These bioproducts, as well as being good alternatives to minimize production waste, reduce the use of petroleum and consequently emissions of greenhouse gases. Biochar was obtained by slow pyrolysis of coffee grounds. In order to evaluate the the fuel capacity, characterization was carried out through physical-chemical analyses to measure moisture, ash, volatile material and fixed carbon contents, and elemental analysis to determine theoretical calorific value. The activated biochar was also tested as an adsorbent of organic dyes
Low temperature conversion (LTC) of castor seeds : a study of the oil fraction (pyrolysis oil)
5 p. : il.The low temperature conversion (LTC) process applied to a castor seed sample at 380 8C produced pyrolysis oil (50%,w/w), pyrolytic char (29%, w/w), water (13%, w/w) and gas (8%, w/w) fractions. The oil fraction was subjected to analysis of by FTIR, 1H NMR, 13C NMR, GCMS and physical–chemical analysis such as sulfur content, distillation, density, flash-point, kinematic viscosity, Ramsbottom carbon residue, ash content, corrosivity to copper, water content and sediment, cold filter plugging point, and gross calorific value
Estudo de fatores que influenciam o cálculo de incerteza da medição de atenuação em lÃquidos
12 p. : il.Incerteza é um parâmetro metrológico definido e inerente a qualquer experimento
cientÃfico. Determinar, quantificar e combinar as incertezas melhora o padrão de
qualidade e a confiabilidade metrológica dos resultados obtidos. Neste trabalho, a
incerteza da medição de atenuação de lÃquidos foi estudada com o objetivo de se
identificar os principais parâmetros que influenciam nesta incerteza. Para medir a
atenuação utilizou-se o método ultrassônico de transmissão => recepção. Portanto,
para cada frequência estudada, empregou-se um par de transdutores de mesma
frequência nominal de ressonância. Foram utilizados 4 transdutores e 9 pontos de
frequências variando entre 1.0 MHz e 5.0 MHz. Para o arranjo experimental
proposto, foram encontradas incertezas combinadas inferiores a 1% em todos os
casos
Sensibility of hydrous ethanol adulteration detection using ultrasonic parameters validated in a metrological base
7 p. : il.The aim of this study is to identify possible changes in fuels, in this case hydrous ethanol, through ultrasonic parameters such as attenuation and propagation speed. The system setup and method were implemented at Inmetro’s Laboratory of Ultrasound. Experiments and method uncertainties were assessed accordingly to ISO/IEC Guide 98 1:2009 (Uncertainty of measurement – Part 1: Introduction to the expression of uncertainty in measurement). Mixtures of ethanol and water varying from 90% to 94% of alcohol in mass were used as testing samples. Attenuation and propagation speed were accurately measured and uncertainties evaluated. The accordingly to Brazilian biofuel regulations, the concentration of water in hydrous ethanol can be accepted at a maximum concentration of 93.8 and minimum of 92.6 of alcohol in mass. To achieve that figure, a functional combination of tested parameters should be implemented. Those results could be used as a tool to identify adulteration of biofuel, even in analysis performed on site
Pyrolysis Oil from the Fruit and Cake of Jatropha curcas Produced Using a Low Temperature Conversion (LTC) Process: Analysis of a Pyrolysis Oil-Diesel Blend
Highly Functionalized Microporous Activated Biochar from Syagrus coronata Waste: Production, Characterization, and Application in Adsorption Studies
The presence of emerging contaminants in water can harm both the environment and human health. Traditional water and wastewater treatment cannot eliminate them, so different alternatives for their removal are being studied. The use of activated carbon as an adsorbent is emphasized due to its high adsorption capacity and lower cost, and to the possibility of obtaining it from biomass wastes. Thus, this study evaluated the use of Syagrus coronata waste to produce activated biochars and their adsorption capacity of isoniazid from an aqueous medium. For this, the biochar obtained through slow pyrolysis was chemically activated using two different agents, H2SO4 or KOH. The adsorbent’s acidic and textural properties were studied and correlated with adsorption behavior tested in batch and fixed-bed column systems, using commercial activated carbon as a comparison. The KOH activation process produced a predominantly microporous material (BAC), with a high surface area (1006 m2·g−1) and a high content of oxygenated functional groups (1.98 mmol·g−1). BAC outperformed all other materials tested and ones found in other works using isoniazid as a contaminant model, having a high adsorption capacity (712.42 mg·g−1). Thus, this work successfully obtained an efficient adsorbent produced from an agro-industrial waste, with superior performance