cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.6084/m9.figshare.14290484
title: The effect of SDS surfactant on surface reaeration coefficient: a laboratory scale approach

description: Abstract Surface reaeration coefficient (K2), which represents the transfer of oxygen at the air-water interface, is an important variable in aquatic ecosystems. K2 is influenced by several factors, including surfactants; furthermore, this coefficient is used in water-quality models, which requires its correct estimation. This study evaluated the effects of the surfactant Sodium Dodecyl Sulfate (SDS) on K2 in two different experimental systems. In a cylindrical reactor with a turbine-type mechanical stirrer, 15 reaeration experiments were carried out with SDS concentrations of 0.0; 0.25; 0.5; 1.0 and 1.5 mMol L-1 and stirrer rotation velocities of 25, 50 and 100 rpm. In a circular hydraulic channel, 8 reaeration experiments were carried out, in triplicate, with SDS concentrations of 0 and 1.5 mMol L-1 and agitation levels of Reynolds 4,500, 37,500; 49,200 and 54,000. In the reactor, regardless of the rotation velocity, the surfactant reduced K2 by 20%, due to a superficial film formation at the interface that made oxygen transfer difficult, due to a phenomenon known as “barrier effect”. In the channel, an approximate K2 reduction of 15% occurred at higher levels of water agitation. In the presence of surfactants, and at low levels of agitation, phenomena that increase K2 (i.e., Marangoni effect) may coexist with those that reduce K2 (i.e., barrier effect). We concluded that the presence of SDS in aquatic environments should be considered when estimating the surface reaeration coefficient, because this surfactant can contribute to uncertain K2 estimation.
DOI: 10.6084/m9.figshare.14290484.v1
title: The effect of SDS surfactant on surface reaeration coefficient: a laboratory scale approach

description: Abstract Surface reaeration coefficient (K2), which represents the transfer of oxygen at the air-water interface, is an important variable in aquatic ecosystems. K2 is influenced by several factors, including surfactants; furthermore, this coefficient is used in water-quality models, which requires its correct estimation. This study evaluated the effects of the surfactant Sodium Dodecyl Sulfate (SDS) on K2 in two different experimental systems. In a cylindrical reactor with a turbine-type mechanical stirrer, 15 reaeration experiments were carried out with SDS concentrations of 0.0; 0.25; 0.5; 1.0 and 1.5 mMol L-1 and stirrer rotation velocities of 25, 50 and 100 rpm. In a circular hydraulic channel, 8 reaeration experiments were carried out, in triplicate, with SDS concentrations of 0 and 1.5 mMol L-1 and agitation levels of Reynolds 4,500, 37,500; 49,200 and 54,000. In the reactor, regardless of the rotation velocity, the surfactant reduced K2 by 20%, due to a superficial film formation at the interface that made oxygen transfer difficult, due to a phenomenon known as “barrier effect”. In the channel, an approximate K2 reduction of 15% occurred at higher levels of water agitation. In the presence of surfactants, and at low levels of agitation, phenomena that increase K2 (i.e., Marangoni effect) may coexist with those that reduce K2 (i.e., barrier effect). We concluded that the presence of SDS in aquatic environments should be considered when estimating the surface reaeration coefficient, because this surfactant can contribute to uncertain K2 estimation.
DOI: 10.6084/m9.figshare.14290486
title: Control charts for monitoring drip irrigation with different hydraulic heads

description: Abstract This study monitored a drip irrigation system with different hydraulic heads, using control charts. The study included 25 tests, and was conducted at the Experimental Nucleus of Agricultural Engineering of the State University of Western Paraná, located in the municipality of Cascavel, Paraná. The drip irrigation system was operated by gravity, and had four hydraulic heads (10, 11, 12 and 15 kPa). The uniformity of the system was determined based on uniformity distribution. Uniformity monitoring was performed using Shewhart and exponentially weighted moving-average (EWMA) control charts. An increase in the hydraulic head increased uniformity. The use of 12 and 15 kPa hydraulic heads yielded good performance, whereas 10 and 11 kPa yielded regular performance. The use of control charts proved to be efficient; the Shewhart control chart was more robust, whereas the EWMA control chart, which indicated trends and deviations not shown by Shewhart control charts, was more sensitive.
DOI: 10.6084/m9.figshare.14290489.v1
title: Connectivity as the control key to intensity of flood pulse in Taquari River oxbow lakes

description: Abstract The Taquari River is one of the most important tributaries of the Paraguay River, whose sediments are carried and deposited on the plain forming the largest alluvial fan in the world, known as Pantanal. In the floodplain, the course of the river has been modified by the sedimentation process, resulting in lakes with different degrees of connectivity with the river. This study assessed the influence of connectivity on the physical and chemical characteristics of water along a hydrological cycle in oxbow lakes of the Taquari River floodplain, in Mato Grosso do Sul, Brazil. Sampling was carried out monthly, from May 2005 to June 2006.The physical and chemical data of the water and the variables of river level and rainfall intensity were correlated by Principal Component Analysis (PCA). Limnological differences resulted from distinct degrees of connectivity between the oxbow lakes and the Taquari River. Variations in the dry and rainy seasons established a gradient that extends over a space-time continuum and generates greater environmental heterogeneity and, consequently, greater biodiversity. Thus we conclude that this mosaic of lakes and the surrounding landscape requires protection and preservation because of its importance for biodiversity conservation.
DOI: 10.6084/m9.figshare.14290486.v1
title: Control charts for monitoring drip irrigation with different hydraulic heads

description: Abstract This study monitored a drip irrigation system with different hydraulic heads, using control charts. The study included 25 tests, and was conducted at the Experimental Nucleus of Agricultural Engineering of the State University of Western Paraná, located in the municipality of Cascavel, Paraná. The drip irrigation system was operated by gravity, and had four hydraulic heads (10, 11, 12 and 15 kPa). The uniformity of the system was determined based on uniformity distribution. Uniformity monitoring was performed using Shewhart and exponentially weighted moving-average (EWMA) control charts. An increase in the hydraulic head increased uniformity. The use of 12 and 15 kPa hydraulic heads yielded good performance, whereas 10 and 11 kPa yielded regular performance. The use of control charts proved to be efficient; the Shewhart control chart was more robust, whereas the EWMA control chart, which indicated trends and deviations not shown by Shewhart control charts, was more sensitive.
DOI: 10.6084/m9.figshare.14290489
title: Connectivity as the control key to intensity of flood pulse in Taquari River oxbow lakes

description: Abstract The Taquari River is one of the most important tributaries of the Paraguay River, whose sediments are carried and deposited on the plain forming the largest alluvial fan in the world, known as Pantanal. In the floodplain, the course of the river has been modified by the sedimentation process, resulting in lakes with different degrees of connectivity with the river. This study assessed the influence of connectivity on the physical and chemical characteristics of water along a hydrological cycle in oxbow lakes of the Taquari River floodplain, in Mato Grosso do Sul, Brazil. Sampling was carried out monthly, from May 2005 to June 2006.The physical and chemical data of the water and the variables of river level and rainfall intensity were correlated by Principal Component Analysis (PCA). Limnological differences resulted from distinct degrees of connectivity between the oxbow lakes and the Taquari River. Variations in the dry and rainy seasons established a gradient that extends over a space-time continuum and generates greater environmental heterogeneity and, consequently, greater biodiversity. Thus we conclude that this mosaic of lakes and the surrounding landscape requires protection and preservation because of its importance for biodiversity conservation.
DOI: 10.6084/m9.figshare.14290492
title: Potentialities of water charge in the management of Brazilian water resources

description: Abstract We investigated the application of economic instruments in the management of Brazilian water resources as mechanisms to stimulate the rational use of water and to recognise its economic value. We analysed water-charge scenarios at the national and international levels as a methodology to provide an economic estimate of environmental services related to water resources. Through bibliographical and documentary research, we identified the economic instruments applied to Brazilian water-resource management, describing the methodologies and values used Brazilian water charges and in some member states of the Organization for Economic Cooperation and Development. We identified how economic valuation methods of environmental resources could contribute to the improvement of water charges, considering the environmental services offered by a healthy river basin. In the Brazilian and the international scenarios, water charge methodologies include the volumetry of abstracted or consumed water, associating some elements that indicate the pollution level. The prices per cubic meter of water are still very low in all the scenarios. Environmental valuation techniques can be an essential tool for rethinking the methodologies and costs applied in water charges, increasing the potential of water’s rational use through economic instruments.
DOI: 10.6084/m9.figshare.14290494
title: Impact of fulvic acid and free amino acids on paclobutrazol absorption by ‘Keitt’ mango

description: Abstract This study evaluated the impact of fulvic acid and free amino acids on paclobutrazol soil residue, their absorption and effects on ‘Keitt’ mango grown in tropical semi-arid environmental conditions. The experiment was carried out from 2017 to 2018 simultaneously in two orchards with the same plants and management characteristics, located in Cabrobó, Pernambuco, Brazil. The experimental design was randomized blocks with four treatments, five replications and four plants per replication. The treatments consisted of paclobutrazol combinations with acid fulvic and free amino acids, as follows: Treatment 1: paclobutrazol + water (control); Treatment 2: paclobutrazol + fulvic acids; Treatment 3: paclobutrazol + free amino acids; and Treatment 4: paclobutrazol + fulvic acids + free amino acids. According to the results, the use of fulvic acids, free amino acids or both affects the paclobutrazol absorption by 'Keitt' mango. The addition of fulvic acid to the paclobutrazol improves the absorption of this molecule by the plant, with greater inhibition of vegetative growth of 'Keitt' mango and lower soil residues.
DOI: 10.6084/m9.figshare.14290494.v1
title: Impact of fulvic acid and free amino acids on paclobutrazol absorption by ‘Keitt’ mango

description: Abstract This study evaluated the impact of fulvic acid and free amino acids on paclobutrazol soil residue, their absorption and effects on ‘Keitt’ mango grown in tropical semi-arid environmental conditions. The experiment was carried out from 2017 to 2018 simultaneously in two orchards with the same plants and management characteristics, located in Cabrobó, Pernambuco, Brazil. The experimental design was randomized blocks with four treatments, five replications and four plants per replication. The treatments consisted of paclobutrazol combinations with acid fulvic and free amino acids, as follows: Treatment 1: paclobutrazol + water (control); Treatment 2: paclobutrazol + fulvic acids; Treatment 3: paclobutrazol + free amino acids; and Treatment 4: paclobutrazol + fulvic acids + free amino acids. According to the results, the use of fulvic acids, free amino acids or both affects the paclobutrazol absorption by 'Keitt' mango. The addition of fulvic acid to the paclobutrazol improves the absorption of this molecule by the plant, with greater inhibition of vegetative growth of 'Keitt' mango and lower soil residues.
DOI: 10.6084/m9.figshare.14290492.v1
title: Potentialities of water charge in the management of Brazilian water resources

description: Abstract We investigated the application of economic instruments in the management of Brazilian water resources as mechanisms to stimulate the rational use of water and to recognise its economic value. We analysed water-charge scenarios at the national and international levels as a methodology to provide an economic estimate of environmental services related to water resources. Through bibliographical and documentary research, we identified the economic instruments applied to Brazilian water-resource management, describing the methodologies and values used Brazilian water charges and in some member states of the Organization for Economic Cooperation and Development. We identified how economic valuation methods of environmental resources could contribute to the improvement of water charges, considering the environmental services offered by a healthy river basin. In the Brazilian and the international scenarios, water charge methodologies include the volumetry of abstracted or consumed water, associating some elements that indicate the pollution level. The prices per cubic meter of water are still very low in all the scenarios. Environmental valuation techniques can be an essential tool for rethinking the methodologies and costs applied in water charges, increasing the potential of water’s rational use through economic instruments.
DOI: 10.6084/m9.figshare.14290498
title: Water resources, public policies and the COVID-19 pandemic

description: Abstract The novel coronavirus pandemic has resulted in global socioeconomic impacts; however, there is still a need to improve understanding and data about its form and patterns of propagation. Therefore, studies on the role of water resources and sanitation should be prioritized, given the potential to serve as a means of dispersing the SARS-CoV-2 virus, which causes COVID-19 disease. So far, the RNA of the transmitting virus has been detected in domestic sewage in several countries, but there is, so far, no evidence of contamination by direct contact with these effluents. Even so, poor regions without adequate treatment of water and sewage, as occur in Brazil, must act in order to develop efficient policies to improve water quality aimed at public health. One of the options is the formation of a Hub that aggregates the various interrelated aspects of water and sanitation into a cohesive and actionable whole. It is essential to combine investment, research, and monitoring of water and effluent quality to improve sanitary security, water quality and human health, with an emphasis on the poorest sectors. The Hub would also serve as a means of controlling and monitoring the dispersion of pathogens such as the SARS-CoV-2 virus, thus mitigating economic and societal impacts.
DOI: 10.6084/m9.figshare.14290496
title: Evaluation of water quality and sanitation of reservoirs used in field activities of a military unit in the state of Rio de Janeiro

description: Abstract In the Armed Forces' campaign activities, large troops may be exposed to serious health risks even before war itself. In 2010, for example, the Brazilian Army sent nearly 2,000 men to join the United Nations peacekeeping mission in Haiti, which was experiencing a cholera epidemic. This work therefore investigated the water quality and sanitation of the various types of reservoirs used in four field-training activities of a Brazilian Army Unit located in the state of Rio de Janeiro. Physicochemical and microbiological analyses of the water were carried out, and visual inspections and swab samples were collected from the inner surface of these reservoirs for counting coliform bacteria and counting mesophilic aerobic microorganisms. Physicochemical and microbiological analyses of water from different types of reservoirs revealed a lack of conformity with American Public Health Association and Ordinance Number 518, of 03/25/04, of the Brazilian Ministry of Health . It was observed that 50% of the collective and individual reservoirs did not have the desirable minimum levels of Free Residual Chlorine. In addition, in 35.7% of the total collective and individual reservoirs evaluated there was growth of coliform group bacteria and in 28.57% of them the number of heterotrophic bacteria exceeded the maximum recommendation. According to the swabs performed on the inner surfaces, results of the total viable mesophilic aerobic counts were above the recommended levels in 78.57% of the total evaluated reservoirs. Besides that, in the Lyster bags of activities 1 and 2, there was growth of coliforms, or 14.28% of the total evaluated reservoirs. It was concluded that there were failures in the management of multiple barriers during storage and / or distribution, as well as in the maintenance of disinfection to prevent or eliminate microbial contamination, indicating the need for corrective measures.
DOI: 10.6084/m9.figshare.14290496.v1
title: Evaluation of water quality and sanitation of reservoirs used in field activities of a military unit in the state of Rio de Janeiro

description: Abstract In the Armed Forces' campaign activities, large troops may be exposed to serious health risks even before war itself. In 2010, for example, the Brazilian Army sent nearly 2,000 men to join the United Nations peacekeeping mission in Haiti, which was experiencing a cholera epidemic. This work therefore investigated the water quality and sanitation of the various types of reservoirs used in four field-training activities of a Brazilian Army Unit located in the state of Rio de Janeiro. Physicochemical and microbiological analyses of the water were carried out, and visual inspections and swab samples were collected from the inner surface of these reservoirs for counting coliform bacteria and counting mesophilic aerobic microorganisms. Physicochemical and microbiological analyses of water from different types of reservoirs revealed a lack of conformity with American Public Health Association and Ordinance Number 518, of 03/25/04, of the Brazilian Ministry of Health . It was observed that 50% of the collective and individual reservoirs did not have the desirable minimum levels of Free Residual Chlorine. In addition, in 35.7% of the total collective and individual reservoirs evaluated there was growth of coliform group bacteria and in 28.57% of them the number of heterotrophic bacteria exceeded the maximum recommendation. According to the swabs performed on the inner surfaces, results of the total viable mesophilic aerobic counts were above the recommended levels in 78.57% of the total evaluated reservoirs. Besides that, in the Lyster bags of activities 1 and 2, there was growth of coliforms, or 14.28% of the total evaluated reservoirs. It was concluded that there were failures in the management of multiple barriers during storage and / or distribution, as well as in the maintenance of disinfection to prevent or eliminate microbial contamination, indicating the need for corrective measures.
DOI: 10.6084/m9.figshare.14290498.v1
title: Water resources, public policies and the COVID-19 pandemic

description: Abstract The novel coronavirus pandemic has resulted in global socioeconomic impacts; however, there is still a need to improve understanding and data about its form and patterns of propagation. Therefore, studies on the role of water resources and sanitation should be prioritized, given the potential to serve as a means of dispersing the SARS-CoV-2 virus, which causes COVID-19 disease. So far, the RNA of the transmitting virus has been detected in domestic sewage in several countries, but there is, so far, no evidence of contamination by direct contact with these effluents. Even so, poor regions without adequate treatment of water and sewage, as occur in Brazil, must act in order to develop efficient policies to improve water quality aimed at public health. One of the options is the formation of a Hub that aggregates the various interrelated aspects of water and sanitation into a cohesive and actionable whole. It is essential to combine investment, research, and monitoring of water and effluent quality to improve sanitary security, water quality and human health, with an emphasis on the poorest sectors. The Hub would also serve as a means of controlling and monitoring the dispersion of pathogens such as the SARS-CoV-2 virus, thus mitigating economic and societal impacts.
DOI: 10.6084/m9.figshare.14290500
title: DOF/DAF comparison for the treatment of milk industry wastewater

description: Abstract The objective of this study was to evaluate the efficiency of dissolved ozone flotation (DOF) in comparison to dissolved air flotation (DAF) for treatment of milk industry wastewater (MW). In the first phase of the experiment, a synthetic milk wastewater (SMW) was used to evaluate DOF and DAF, with and without addition of hydrogen peroxide, at pH 4.0 and pH 11.4. In the DOF tests, the concentration of ozone was equal to 19 (± 0.5) mg L-1 and in the tests with addition of hydrogen peroxide, the H2O2/O3 ratios tested were 0.5, 1.0 and 1.5. In the second phase, tests were performed using three MW from three different industries to validate the results obtained and to determine the DOF system's ability to treat this type of effluent. The parameters tested during validation were turbidity, total suspended solids, oils and greases (O&G), chemical oxygen demand (COD), biochemical oxygen demand (BOD), total nitrogen (TN) and total phosphorus (TP). It was observed that the efficiency of the treatments was better at pH 4.0. The results showed a reduction of the efficiency with the use of DOF. The addition of H2O2 in DAF and DOF also resulted in reduced system efficiency. The results obtained with SMW only approximated those obtained with the MW from one of the industries that contained the largest traces of milk and cheese.
DOI: 10.6084/m9.figshare.14290500.v1
title: DOF/DAF comparison for the treatment of milk industry wastewater

description: Abstract The objective of this study was to evaluate the efficiency of dissolved ozone flotation (DOF) in comparison to dissolved air flotation (DAF) for treatment of milk industry wastewater (MW). In the first phase of the experiment, a synthetic milk wastewater (SMW) was used to evaluate DOF and DAF, with and without addition of hydrogen peroxide, at pH 4.0 and pH 11.4. In the DOF tests, the concentration of ozone was equal to 19 (± 0.5) mg L-1 and in the tests with addition of hydrogen peroxide, the H2O2/O3 ratios tested were 0.5, 1.0 and 1.5. In the second phase, tests were performed using three MW from three different industries to validate the results obtained and to determine the DOF system's ability to treat this type of effluent. The parameters tested during validation were turbidity, total suspended solids, oils and greases (O&G), chemical oxygen demand (COD), biochemical oxygen demand (BOD), total nitrogen (TN) and total phosphorus (TP). It was observed that the efficiency of the treatments was better at pH 4.0. The results showed a reduction of the efficiency with the use of DOF. The addition of H2O2 in DAF and DOF also resulted in reduced system efficiency. The results obtained with SMW only approximated those obtained with the MW from one of the industries that contained the largest traces of milk and cheese.