Microscopic Displacement of Bitumen During Solvent-Steam-Flooding: Effects of Reservoir Clays and Solvent Type

Solvent-steam-flooding (SSF) processes have several advantages over steamflooding for bitumen extraction. It is well known that the addition of solvent increases oil production and mitigates environmental impacts due to steam generation. However, there exist numerous unknowns on the mutual interactions of solvent with steam, reservoir oil, and reservoir rock which affect the overall performance of the EOR method. Through an experimental approach, this study investigates the microscopic displacement efficiency of SSF for the extraction of Peace River bitumen. Two types of gas phase solvents were tested: hydrocarbon (propane) and nonhydrocarbon (carbon dioxide - CO2). Propane was chosen for its good solubility in oil, whereas CO2 was selected as an environmentally friendly option to decrease the project’s carbon footprint by re-injecting boiler combustion or associated gas. Solvent flooding (CO2 flooding and propane flooding), steam-flooding, and SSF performances to extract Peace River bitumen were investigated with 12 one-dimensional core flooding experiments. Process performances were evaluated with cumulative oil recovery, sweep efficiency, produced oil and residual oil quality analyses. To investigate the effect of reservoir fines (clays), experiments were performed with and without clays on the reservoir rock. The phase behavior of the solvent-crudeasphaltene interactions was also studied by analyzing asphaltene precipitation. Finally, the impacts of varying the solvent flowrate were also studied. This research study suggests that CO2 or propane insoluble fractions (asphaltenes) decrease permeability and increase oil viscosity during solvent flooding due to their interactions with clays. These problems are enhanced by solvent-steam co-injection, which also causes the formation of emulsions. Clay migration to oil phase during production is more significant for propane-steam co-injection. It is believed that the polar nature of asphaltenes is the reason behind the interactions with clays and water

Estratégias de desenvolvimento industrial e dinâmicas territoriais de contestação social e confronto político

O artigo discute o conflito socioambiental estabelecido na interação entre o desenvolvimento de estratégias industriais em rede, através da Companhia Siderúrgica Nacional (CSN), e formas emergentes de contestação social e confronto politico nas localidades siderúrgicas e de extração mineral de Volta Redonda (RJ) e Congonhas (MG). O argumento central enfatiza a importância dessas formas de enraizamento social como condicionantes da ação econômica, considerando principalmente a natureza inovadora da integração de questões do trabalho e do meio ambiente nos territórios pesquisados

Determination of Copper Price Expectations in the International Market: Some Important Variables

The purpose of this work is to identify variables that are relevant to the copper price setting in the international market. Thus statistical hypothesis tests and statistical tools that help to identify historical relevance and to measure the intensity of the impact of each variable on the copper price on several time horizons were applied. At the end, a regression model that aims to assess the combined effect of the considered time series was estimated. The global industrial production and the aluminum price showed the greatest evidences of being relevant to the copper price. The results suggest that copper stocks, foreign exchange rates and crude oil price should also be considered

USE OF NANOCOMPOSITE HYDROGEL WITH N-UREA IN THE PRODUCTION OF EGGPLANT SEEDLINGS

The use of quality seedlings of eggplant is directly related to the success of their production, with polymers added to the substrate, which work as water conditioners, increase the water retention capacity, and provide better seedling quality. The study aimed to evaluate the use of nanocomposite hydrogel enriched with different proportions of N-urea in the production of eggplant seedlings. The experiment was conducted at the State University of Mato Grosso do Sul, Cassilândia, MS, Brazil, from June to August 2019, under sombrite® 30%. Five treatments were evaluated, using the commercial substrate, Carolina Soil®: 1) commercial substrate without hydrogel; 2) commercial substrate with 0.075g of pure hydrogel (0.00g of N-urea)/15 mL of a substrate; 3) commercial substrate with 0.075g of hydrogel and 10% N-urea/15 mL of a substrate; 4) commercial substrate with 0.075g of hydrogel and 20% N-urea/15 mL of a substrate, and 5) commercial substrate with 0.075g of hydrogel and 40% N-urea/15 mL of a substrate. The experiment was conducted with four replications of 25 seedlings. The emergence speed index, percentage of emergence, height, number of leaves, stem diameter, shoot dry matter, root dry matter, and total dry matter were evaluated, as well as the Dickson Quality Index. The data were subjected to analysis of variance (SPEEDSTAT statistical software) and grouping test of means. A regression analysis was performed to adjust equations for some of the variables. The best seedlings can be obtained using the dosage of 28.83% N-urea with 0.075g of hydrogel per 15 ml of the substrate, according to the DQI adjustment, which includes several traits of the seedlings, thus reflecting on its quality

RRH: síndrome de envenenamento por 200 ferroadas de abelhas africanizadas

Envenoming syndrome from Africanized bee stings is a toxic syndrome caused by the inoculation of large amounts of venom from multiple bee stings, generally more than five hundred. The incidence of severe toxicity from Africanized bee stings is rare but deadly. This report reveals that because of the small volume of distribution, having fewer stings does not exempt a patient from experiencing an unfavorable outcome, particularly in children, elderly people or underweight people.A síndrome de envenenamento por ferroadas de abelhas africanizadas é causada pela inoculação de uma grande quantidade de peçonha por múltiplas ferroadas de abelhas, geralmente acima de quinhentas. A incidência de uma intoxicação severa por ferroadas de abelhas africanizadas é rara, porém letal. Este relato de caso aponta que, devido a um menor volume de distribuição do veneno, um número menor de ferroadas por abelhas africanizadas não exime o paciente de apresentar envenenamentos com desfecho desfavorável, principalmente em crianças, idosos e pessoas com baixo peso

Sistemas fuzzy complementam a detecção de socialbots por aprendizado de máquina / Fuzzy systems complement machine learning socialbot detection

A detecção de socialbots em Redes Sociais Online tem sido objeto de diversos estudos baseados em aprendizado de máquina. Este trabalho apresenta o uso de um comitê de classificadores para melhorar a acurácia da identificação de socialbots. O comitê associa o conhecimento obtido por algoritmos de aprendizado de máquina ao conhecimento heurístico humano, obtido por entrevistas e formalizado por regras fuzzy. Os resultados mostram que estas abordagens são complementares, uma vez que o uso conjunto destes algoritmos em um comitê apresenta uma acurácia acima de 93%, maior do que os mesmos algoritmos utilizados isoladamente. 

Clinical trial for evaluation of Ricinus communis and sodium hypochlorite as denture cleanser

The development of opportunistic infections due to poor denture hygiene conditions justified the search for effective hygiene protocols for controlling denture biofilm. Objective This study evaluated Ricinus communis and sodium hypochlorite solutions in terms of biofilm removal ability, remission of candidiasis, antimicrobial activity, and participant satisfaction. Material and Methods It was conducted a controlled clinical trial, randomized, double-blind, and crossover. Sixty-four denture wearers with (n=24) and without candidiasis (n=40) were instructed to brush (3 times/day) and immerse their dentures (20 min/day) in different storage solutions (S1 / S2: 0.25% / 0.5% sodium hypochlorite; S3: 10% R. communis; S4: Saline).The trial period for each solution was seven days and a washout period of seven days was used before starting the use of another solution. The variables were analyzed at baseline and after each trial period. The biofilm of inner surfaces of maxillary dentures was disclosed, photographed, and total and dyed areas were measured (Image Tool software). The percentage of biofilm was calculated. Remission of candidiasis was assessed by visual scale and score were attributed. Antimicrobial activity was assessed by the DNA-Checkerboard hybridization method. Patient satisfaction was measured using a questionnaire. Results S1 (4.41±7.98%) and S2 (2.93±5.23%) were more effective then S3 (6.95±10.93%) in biofilm remotion(

Non-neoplastic bulky mediastinal mass presentation in an adolescent patient: a case report

Abstract : Introduction Mediastinal masses in pediatric patients are very heterogeneous in origin and etiology. In the first decade of life, 70% of the mediastinal masses are benign whereas malignant tumors are more frequent in the second decade of life. Among the mediastinal masses, lymph nodes are the most common involved structures and could be enlarged due to a lymphoma, leukemia, metastatic disease, or due to infectious diseases as sarcoidosis, tuberculosis and others. Case presentation. We report a case of a 13-year-old Caucasian girl who came to the emergency room with a history of intermittent fever, weight loss and night sweating for at least 1 month. A radiologic image work-up presented an anterior and posterior mediastinal mass. The 18F-fluorodeoxyglucose positron emission tomography presented a high maximum standard uptake value, which directed our decision for mediastinal biopsy for diagnostic elucidation. Histologic examination described the mass as granulomatous tuberculosis. The patient was treated with anti-tuberculosis therapy and developed a full clinical recovery. Conclusions . The present case report demonstrates that a bulky mediastinal lymphadenopathy detected on 18F-fluorodeoxyglucose positron emission tomography is not always a malignant lesion, and in countries where tuberculosis is endemic, this etiology should not be forgotten during clinical investigations. There is a need for more accurate cut-off values for this technology; meanwhile, the further investigation of patients with bulky mediastinal masses with procedures such as the open biopsy is indispensable

Uso de redes neurais artificais na predi??o de valores gen?ticos para peso aos 205 dias em bovinos da ra?a Tabapu?.

Dados de 19240 animais Tabapu?, provenientes de 152 fazendas localizadas em diversos estados brasileiros, nascidos entre 1976 e 1995, foram utilizados para predi??o do valor gen?tico do peso aos 205 dias de idade (VG_P205) por meio de redes neurais artificiais (RNAs) e usando o algoritmo LM ? Levenberg Marquardt ? para treinamento dos dados de entrada. Por se tratar de rede com aprendizado supervisionado, foram utilizados, como sa?da desejada, os valores gen?ticos preditos pelo BLUP para a caracter?stica P205. Os valores gen?ticos do P205 obtidos pela RNA e os preditos pelo BLUP foram altamente correlacionados. A ordena??o dos valores gen?ticos do P205 oriundos das RNAs e os valores preditos pelo BLUP (VG_P205_RNA) sugeriram que houve varia??o na classifica??o dos animais, indicando riscos no uso de RNAs para avalia??o gen?tica dessa caracter?stica. Inser??es de novos animais necessitam de novo treinamento dos dados, sempre dependentes do BLUP.Data from 19,240 Tabapu? animals from 152 farms located in different states of Brazil, born from 1976 to 1995, were used to predict the genetic value of body weight at 205 days of age (BV_P205) of Tabapu? beef cattle using Artificial Neural Networks (ANN) and LM algorithm - Levenberg Marquardt training for data entry. Due to the use of networks with supervised learning, the predicted breeding values for P205 from BLUP were used as desired output. The breeding values for P205 obtained from RNA and those predicted by BLUP were highly correlated. The ranked breeding values for body weight at 205 days through RNA and those predicted by BLUP (VG_P205_RNA) showed a variation in the classification of animals indicating risks in the use of ANNs procedure for genetic evaluation of this trait. Insertions of new animals require new training data always dependent on BLUP