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1.
Rev Environ Contam Toxicol ; 248: 111-189, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30671689

RESUMO

Metal-rich sediments have the potential to impair life in freshwater streams and rivers and, thereby, to inhibit recovery of ecological conditions after any remediation of mine water discharges. Sediments remain metal-rich over long time periods and have long-term potential ecotoxicological interactions with local biota, unless the sediments themselves are physically removed or replaced by less metal-rich sediment. Laboratory-derived environmental quality standards are difficult to apply to the field situation, as many complicating factors exist in the real world. Therefore, there is a strong case to consider other, field-relevant, measures of toxic effects as alternatives to laboratory-derived standards and to seek better biological tools to detect, diagnose and ideally predict community-level ecotoxicological impairment. Hence, this review concentrated on field measures of toxic effects of metal-rich sediment in freshwater streams, with less emphasis on laboratory-based toxicity testing approaches. To this end, this review provides an overview of the impact of metal-rich sediments on freshwater stream life, focusing on biological impacts linked to metal contamination.


Assuntos
Monitoramento Ambiental , Metais/análise , Mineração , Rios , Poluentes Químicos da Água/análise , Água Doce , Sedimentos Geológicos/química
2.
Rev Environ Contam Toxicol ; 249: 133-152, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30879139

RESUMO

Mercury (Hg) is an environmental contaminant that has been reported in many wildlife species worldwide. The organic form of Hg bioaccumulates in higher trophic levels, and thus, long-lived predators are at risk for higher Hg exposure. Although ecological risk assessments for contaminants such as Hg include pertinent receptor species, snakes are rarely considered, despite their high trophic status and potential to accumulate high levels of Hg. Our current knowledge of these reptiles suggests that snakes may be useful novel biomarkers to monitor contaminated environments. The few available studies show that snakes can bioaccumulate significant amounts of Hg. However, little is known about the role of snakes in Hg transport in the environment or the individual-level effects of Hg exposure in this group of reptiles. This is a major concern, as snakes often serve as important prey for a variety of taxa within ecosystems (including humans). In this review, we compiled and analyzed the results of over 30 studies to discuss the impact of Hg on snakes, specifically sources of exposure, bioaccumulation, health consequences, and specific scientific knowledge gaps regarding these moderate to high trophic predators.


Assuntos
Monitoramento Ambiental , Mercúrio/metabolismo , Serpentes/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Biomarcadores/metabolismo , Ecossistema , Humanos
3.
Rev Environ Contam Toxicol ; 251: 1-24, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31011831

RESUMO

Heavy metal pollution in surface water is a global environmental problem. This study analyzed the trends, health risks, and sources of eight dissolved heavy metal species in river and lake water across five continents (Africa, Asia, Europe, North America, and South America; Oceania was excluded owing to a lack of data) for the period 1970-2017. We wanted to assess the effects of various implemented countermeasures to pollution and to determine those that could be adopted worldwide. Collectively, the water system showed increasing trends for Cd, Cr, Cu, Ni, Mn, and Fe and decreasing trends for Pb and Zn. The mean dissolved concentrations of most heavy metals were highest in Asia and lowest in Europe. Most heavy metals had low non-carcinogenic risks over this period. The cancer risks associated with Pb were lower than the hazardous level on all five continents over the five decades, whereas the cancer risks related to Cr exceeded the hazardous level in the 1970s, 2000s, and 2010s, and in Africa, Asia, and North America over the entire period. Mining and manufacturing were consistently found to be critical sources of metal pollution from 1970 to 2017. However, the heavy metal sources differed significantly by continent, with waste discharge and rock weathering dominant in Africa; mining and manufacturing, along with rock weathering, are dominant in Asia and South America; fertilizer and pesticide use, along with rock weathering, are dominant in North America; and mining and manufacturing, waste discharge, and rock weathering are dominant in Europe. Global trends in the metal loadings in water and in relevant pollution-control measures suggest that countermeasures in Europe have successfully controlled heavy metal pollution. The successful measures include implementing rigorous standards for metal emissions, limiting the metal concentrations in products, and rigorously treating metal-contaminated waste. Therefore, the measures implemented in Europe should be extended worldwide to treat heavy metal pollution in water.


Assuntos
Exposição Ambiental/análise , Metais Pesados/análise , Poluentes Químicos da Água/análise , Poluição Química da Água/estatística & dados numéricos , Exposição Ambiental/estatística & dados numéricos , Monitoramento Ambiental , Humanos , Lagos , Rios
4.
Rev Environ Contam Toxicol ; 249: 29-70, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30806801

RESUMO

In recent times there has been remarkable development in the field of soil ecotoxicology and risk assessment (RA) models. It is, however, debatable if these RA models are robust representatives for worldwide relevance. In order to investigate this, the current overview aims to address heavy metal threats to soil life in southern Africa by investigating present knowledge and consequences for RA using research in southern Africa as a case. To this end, the focus is on southern African soils, soil life and living conditions. To critically discuss these issues, we report on extensive research conducted in the southern African context and looked how comparable these findings are to RA models employed in the western world. This is done by providing an inventory of selected studies focused on the ecotoxicity of metals towards soil life. It is concluded that there is a dearth of information on southern African soil life, most of which are laboratory-based studies carried out by a handful of researchers. Future research incorporating the available information into a soil ecosystem assessment procedure is paramount. It is recommended that a starting point to tackle this might be the development of holistic sight-specific guidelines for ecological risk assessment at larger spatial scales (km2) which takes into cognizance landscapes, vegetation and faunal characteristics.


Assuntos
Monitoramento Ambiental , Metais Pesados/análise , Poluentes do Solo/análise , África Austral , Medição de Risco , Solo
5.
Water Sci Technol ; 80(3): 466-477, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31596258

RESUMO

Wetlands are among the most productive ecosystems that provide services ranging from flood control to climate change mitigation. Wetlands are also critical habitats for the survival of numerous plant and animal species. In this study, we used satellite remote sensing techniques for classification and change detection at an internationally important wetland (Ramsar Site) in Turkey. Sultan Marshes is located at the center of semi-arid Develi closed basin. The wetlands have undergone significant changes since the 1980s due to changes in water flow regimes, but changes in recent years have not been sufficiently explored yet. In this study, we focused on the changes from 2005 to 2012. Two multispectral ASTER images with spatial resolution of 15 m, acquired on June 11, 2005 and May 20, 2012, were used in the analyses. After geometric correction, the images were classified into four information classes, namely water, marsh, agriculture, and steppe. The applicability of three classification methods (i.e. maximum likelihood (MLH), multi-layer perceptron type artificial neural networks (ANN) and support vector machines (SVM)) was assessed. The differences in classification accuracies were evaluated by the McNemar's test. The changes in the Sultan Marshes were determined by the post classification comparison method using the most accurate classified images. The results showed that the highest overall accuracy in image classifications was achieved with the SVM method. It was observed that marshes and steppe areas decreased while water and agricultural areas expanded from 2005 to 2012. These changes could be the results of water transfers to the marshes from neighboring watershed.


Assuntos
Monitoramento Ambiental/métodos , Máquina de Vetores de Suporte , Áreas Alagadas , Conservação dos Recursos Naturais , Ecossistema , Eugenol , Redes Neurais (Computação) , Turquia , Óxido de Zinco
6.
Water Sci Technol ; 80(3): 541-550, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31596265

RESUMO

Today, the development and testing of methods for fault detection and identification in wastewater treatment research relies on two important assumptions: (i) that sensor faults appear at distinct times in different sensors and (ii) that any given sensor will function near-perfectly for a significant amount of time following installation. In this work, we show that such assumptions are unrealistic, at least for sensors built around an ion-selective measurement principle. Indeed, long-term exposure of sensors to treated wastewater shows that sensors exhibit fault symptoms that appear simultaneously and with similar intensity. Consequently, this suggests that future research should be reoriented towards methods that do not rely on the assumptions mentioned above. This study also provides the first empirically validated sensor fault model for wastewater treatment simulation, which is useful for effective benchmarking of both fault detection and identification methods and advanced control strategies. Finally, we evaluate the value of redundancy for remote sensor validation in decentralized wastewater treatment systems.


Assuntos
Monitoramento Ambiental/instrumentação , Águas Residuárias , Concentração de Íons de Hidrogênio
7.
Ying Yong Sheng Tai Xue Bao ; 30(9): 3252-3264, 2019 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-31529901

RESUMO

The continuous discharge of pharmaceutical and personal care products (PPCPs) into aquatic environment and their potential threaten to ecological environment or human health has received more and more attention all over the world. Algae are primary producers in aquatic environment and play an important role in ecosystem balance and stabilization. In this review, the concentrations of PPCPs in natural waters from different countries and regions are introduced to demonstrate their characteristics of pollution in aquatic environment. Furthermore, we reviewed some progresses on the toxicity, bioaccumulation and ecological risk of PPCPs. We introduced the toxicity effect and mechanism of PPCPs to algae, the bioaccumulation of PPCPs in algae, as well as the ecological risks of PPCPs in surface water. The review will provide references for development of PPCPs related criteria and assessment of ecological risks in aquatic environment.


Assuntos
Monitoramento Ambiental , Poluentes Químicos da Água/análise , Cosméticos/análise , Cosméticos/toxicidade , Ecossistema , Poluição Ambiental , Água Doce , Humanos , Preparações Farmacêuticas/análise , Poluentes Químicos da Água/toxicidade
8.
Water Sci Technol ; 80(2): 203-212, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31537756

RESUMO

On-site wastewater treatment systems are approved by the French regulation based on the results of platform tests following the European standard NF EN 12566-3. In addition to this approval for the treatment system, at least 90% of outlet concentrations have to be below 30 mg L-1 for total suspended solids (TSS) and 35 mg L-1 for biochemical oxygen demand. The aim of this study is to evaluate the effluent quality of these treatment systems on site, i.e. under real operating conditions, and to assess their performances. Between 2011 and 2016, 1,286 treated wastewater samples were taken from 231 on-site sanitation facilities in France. Data collected are heterogeneous and a robust statistical methodology (using a generalized log-linear model) was used to study the effects of four explanatory variables (treatment systems, loading rate, aging and sampling methods) on the distribution of treated wastewater concentrations. The model calculates median outlet concentrations depending on the effects identified. Its application allowed studying and comparing the outlet median concentrations of 21 on-site sanitation systems classified into nine categories and three groups. Four treatment systems out of the 21 monitored showed TSS median outlet concentrations below 10 mg L-1 and four treatment systems have TSS medians higher than the regulatory threshold of 30 mg L-1.


Assuntos
Eliminação de Resíduos Líquidos/estatística & dados numéricos , Poluição da Água/estatística & dados numéricos , Monitoramento Ambiental , França , Saneamento , Águas Residuárias
9.
Science ; 365(6452): 442-443, 2019 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-31371597
10.
J Nurs Adm ; 49(9): 418-422, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31436739

RESUMO

The need for continuous observation (1:1) of patients for safety precautions, including fall risk, elopement risk, confusion, and aggressive behavior, is highly variable, and it is therefore difficult to plan accurate staffing levels. The high variability in determining when 1:1 staffing for safety is indicated, and for how long, leads to resource strain and high cost to the hospital. A multidisciplinary team analyzed current processes for assigning, monitoring, and discontinuing safety 1:1 care for nonsuicidal patients using Six Sigma methodologies. The team implemented a standardized weaning process to reduce the duration of time on continuous observation and a standardized 4-hour reassessment using a behavior observation-tracking tool to validate the continued need for 1:1 coverage. The interventions resulted in reducing average monthly safety 1:1 staffing hours by 25.6% and saving an estimated $142 000 annually across 6 units. Phase 2 of the project integrated the observation-tracking tool and reassessment check-in into the hospital's electronic medical record for improved tracking and documentation.


Assuntos
Monitoramento Ambiental/economia , Monitoramento Ambiental/métodos , Segurança do Paciente/economia , Gestão da Segurança/economia , Gestão da Segurança/organização & administração , Gestão da Qualidade Total/organização & administração , Eficiência Organizacional , Humanos , Pennsylvania , Projetos Piloto
11.
An Acad Bras Cienc ; 91(supp 3): e20190186, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31365609

RESUMO

The Amazonian rainforest has been subjected to exceptionally high rates of land use change (LUC), primarily for pasture. We present here an analysis of the impact of LUC on trees from studies made in Pará state. LUC results in drastic declines in native species richness, changes species composition and impacts community resilience and ecosystem services provided by the Amazonian rainforest. Given that secondary forests are expanding in Amazonia we argue that this regrowth forest should be taken into account when planning conservation in this region.


Assuntos
Agricultura , Biodiversidade , Monitoramento Ambiental , Solo , Árvores/crescimento & desenvolvimento , Brasil , Humanos
12.
An Acad Bras Cienc ; 91(supp 3): e20190445, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31365613

RESUMO

If we consider Drosophilidae, the answer to the question above is yes. Many research groups in Brazil and abroad have been showing that assemblages of flies of this family can reflect environmental alteration levels caused by urbanization, and/or by other human disturbances. I will present here a summary of our findings in Drosophilidae assemblages reflecting different degrees of environmental perturbation. These studies were done by graduate students of two post graduate programs of UFRGS, under my supervision, along several decades. I will also present the results stemming from the effort of other Brazilian Drosophilid study groups while identifying the members of those assemblages in different Biomes. As a result of those field studies, several biological invasions were detected and many new important biological problems arose prone to be investigated by genetic, molecular biology and other related approaches.


Assuntos
Drosophilidae/fisiologia , Monitoramento Ambiental/métodos , Animais , Brasil , Drosophilidae/classificação , Densidade Demográfica , População Urbana
13.
An Acad Bras Cienc ; 91(3): e20180334, 2019 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-31411254

RESUMO

The aim of this study is to discuss the concentration distribution, composition and possible sources of trace metals and 13 PAHs in topsoils of the University campus, in the city of São Paulo, the largest city of South America. Mineralogy and granulometry of topsoils (0-10 cm) samples, were determined and As, Ba, Cd, Co, Cr, Cu, Mo, Ni, Pb, Sb, V, Zn, Hg, Pt, Pd and PAHs concentrations were quantified in the bulk fraction. The average clay content of soils was 221±61.8 g kg-1 and total carbon was low (mean of 25 g kg-1). Concentrations of metals were generally lower than the reference value established by the São Paulo State Environmental Agency and other studies in the São Paulo urban area, except for Cd, Ni, Pb, Cr and Zn. The mean concentration of the sum of 13 PAHs was 0.33 mg kg-1 and fluorene, indeno(1,2,3-cd)pyrene, anthracene, pyrene and benzo(ghi)perylene were the most abundant compounds. PAHs and trace metals variability were constrained in PMF analysis and showed an association with exhaust and non-exhaust vehicular emissions. The results also pointed out a spatial pattern in the campus area related to traffic conditions and intensity and terrain slope.


Assuntos
Metais Pesados/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Solo/química , Oligoelementos/análise , Universidades , Brasil , Cidades , Monitoramento Ambiental , Humanos , Metais Pesados/química , Hidrocarbonetos Policíclicos Aromáticos/química , Medição de Risco , Análise Espacial , Oligoelementos/química , Poluição Relacionada com o Tráfego/análise , Emissões de Veículos/análise
14.
Ying Yong Sheng Tai Xue Bao ; 30(7): 2191-2200, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31418221

RESUMO

Based on hydrogen and oxygen stable isotopes in precipitation and meteorological data over Shaanxi-Gansu-Ningxia provided by the Global Network of Isotopes in Precipitation (GNIP) and in previous literature, the spatial and temporal variations of oxygen stable isotopes in precipitation and their driving factors were analyzed, the local meteoric water line (LMWL) functions were established. The results showed that the slope and intercept of the LMWL changed in the order of Gansu

Assuntos
Chuva , Vapor , Monitoramento Ambiental , Isótopos de Oxigênio , Estações do Ano
15.
Ying Yong Sheng Tai Xue Bao ; 30(7): 2361-2370, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31418240

RESUMO

Based on pollutant emissions and social-economic data during 2011 and 2015, we selec-ted the total emission index of four pollutants, including the industrial source, agricultural source, and urban living source. The comprehensive index of environmental pollution and sub-source pollution index were built to reflect the pollution of Jilin Province at county scale. Furthermore, the Moran's I, spatial-temporal transition analysis, and standard deviation ellipse analysis were used to quantitatively examine the spatial-temporal evolutionary characteristics of environmental pollution in Jilin Province. A spatial econometric model was built to analyze the influencing factors of environmental pollution. The results showed that environmental pollution in Jilin Province presented spatial agglomeration characteristics, which was mainly concentrating in central areas such as Changchun and Jilin cities. There were obvious regional differences in the spatial distribution of environmental pollution from different sources. There were spatial correlation of the total environmental pollution and agricultural source pollution separately at county scale in Jilin Province. The correlation structure stability of the spatial distribution of environmental pollution was high, which had path locking characteristic. The spatial distribution of environmental pollution showed a northwest-southeast distribution pattern and a spread from the center to the surroundings. The barycenter of environmental pollution moved in the area between 43.65-43.66° N and 125.83-125.84° E. The level of regional economic development, urbanization level and agricultural production were main driving factors for county-scale environmental pollution and industrial source pollution. The adjustment and optimization of industrial structure had improved the overall environmental pollution and industrial source pollution situation. Overuse of chemical fertilizers significantly increased agricultural source pollution. The level of economic development and urbanization were the main drivers of urban living source pollution. The overall environmental pollution and agricultural source pollution had spatial diffusion effects, and their pollution status was closely related to the overall environmental pollution and agricultural source pollution status in adjacent areas, respectively.


Assuntos
Desenvolvimento Econômico , Poluição Ambiental , Agricultura , China , Cidades , Monitoramento Ambiental
16.
Ying Yong Sheng Tai Xue Bao ; 30(7): 2404-2414, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31418244

RESUMO

Based on the net anthropogenic phosphorus input (NAPI) model, we estimated the NAPI of the Dongting Lake basin and its sub-basins from 1985 to 2015, and analyzed the spatio-temporal distributions and variations. The results showed that there was an increasing trend at first and then a decrease in the Dongting Lake basin. The NAPI values in the area in 1985, 1995, 2005 and 2015 were 7.00, 9.20, 10.33, 10.01 kg·hm-2·a-1, respectively. The largest input source changed from the net food and feed import in 1985 to phosphorus fertilizer during 1995-2015. The mean annual input of phosphorus fertilizer, with an average value of 6.01 kg·hm-2·a-1 accounting for 65.8% of NAPI; followed by the food and feed import, the annual average value was 2.65 kg·hm-2·a-1, accounting for 29.0%, and the least was non-food phosphorus, with an average annual value of 0.47 kg·hm-2·a-1, accounting for 5.2%. Spatially, the distribution of NAPI in the Dongting Lake basin showed the characteristics of high in the northeast region and low in the west, which was mainly consistent with distribution of local agriculture. The average annual NAPI values in sub-basin from high to low ranked as following: Dongting Lake area, Xiangjiang River downstream, Zijiang River upstream, Xiangjiang River upstream, Lishui River area, Yuanjiang River upstream, Yuanjiang River downstream and Zijiang River downstream. The highest NAPI was found in the Dongting Lake area, increasing from 13.01 kg·hm-2·a-1 in 1985 to 24.14 kg·hm-2·a-1 in 2015. Agricultural production and population growth were the main contributors to the current input of net phosphorus, and the negative ecological effects of which could not be ignored.


Assuntos
Monitoramento Ambiental , Lagos , Fósforo/análise , Poluentes Químicos da Água/análise , China , Rios
17.
Ying Yong Sheng Tai Xue Bao ; 30(7): 2415-2425, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31418245

RESUMO

The coastal waters in Jiangsu Province have always been an important fishery base since ancient time. In recent years, with the development of the industry in coastal cities, heavy metal pollution is becoming serious in Jiangsu Province. However, the bioaccumulation of heavy metals in the coastal food web is still unclear. In this study, we collected samples (including macroalgae, bivalves, cephalopods, gastropods, crustaceans and fish) through fishery resources survey in the coastal waters of Jiangsu in May 2017 and quantified the main ways of the material circulation and energy flows by constructing the food web using stable carbon and nitrogen isotopes. In addition, the bioaccumulation patterns of eight elements (seven heavy metals and 1 metalloid) through the food chains were investigated. The results showed that there were two energy pathways in this offshore ecosystem: the planktonic food-chain and the benthic food-chain, with Scapharca subcrenata and Phalium strigatum as the primary consumers, respectively. The benthic food-chain was the dominant food chain in energy recycling. The mean concentration of heavy metals from high to low in orga-nisms were Zn, Cu, As, Cd, Cr, Pb, Ni and Hg. The highest concentrations of elements were found in bivalves and the lowest ones in fish. The concentration of As in most species, the levels of Cd in bivalves and Oratosquilla oratoria, the Cr in Coilia mystus and the Zn, Cu, Cr in Ostrea denselamellosa exceeded the proposed health advisory levels. Regarding the bioaccumulation, a decrease in the concentration levels of Zn, Cd and Ni were observed along the planktonic food-chain and a significant positive correlation between Hg and trophic position were found across the benthic food-chain. Other elements had no significant change.


Assuntos
Monitoramento Ambiental , Cadeia Alimentar , Metais Pesados/análise , Poluentes Químicos da Água/análise , Animais , China
18.
Ecotoxicol Environ Saf ; 182: 109458, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31398784

RESUMO

Acid mine drainage (AMD) is a significant contributor of metal pollution leading to ecosystem damage. Bioindicator organisms such as intertidal brown macroalgae have an important role in quantifying the risks of metal bioaccumulation in coastal locations exposed to AMD contamination. Measurement of As, Cd, Cu, Fe, Pb, and Zn accumulation was performed in Fucus serratus, Fucus vesiculosus and Ascophyllum nodosum sampled from two marine locations near to an abandoned Cu mine in Anglesey, Wales, UK. Transect samples were taken from a coastal location (Amlwch) that has seen a substantial increase in AMD contamination over 15 years, in comparison to a nearby estuarine location (Dulas Estuary leading to Dulas Bay) with a historic legacy of pollution. These were compared with samples from the same sites taken 30 years earlier. Some of the Dulas macroalgae samples had Cd, Cu and Zn concentrations that were above background but in general indicated a non-polluted estuary in comparison to substantial pollution over previous decades. In contrast, Fucus samples collected from directly below an AMD outflow at Amlwch showed extremely elevated metal bioaccumulation (>250 mg Fe g-1, >6 mg Cu g-1, >2 mg Zn g-1, >190 µg As g-1) and evidence of macroalgae toxicity, indicating severe pollution at this site. However, the pollution dispersed within 200 m of the outflow source. This study has demonstrated the efficiency of three brown macroalgae species as indicators for metal bioavailability at high spatial resolution and over time.


Assuntos
Monitoramento Ambiental/métodos , Recuperação e Remediação Ambiental , Metais/análise , Mineração , Poluentes Químicos da Água/análise , Biomarcadores Ambientais , Poluição Ambiental , Metais Pesados/análise , Alga Marinha , País de Gales
19.
Environ Res ; 177: 108621, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31421450

RESUMO

2,4,6-trinitrophenol (TNP) is environmentally deleterious substance that has been of pressing societal concern. Therefore, developing a convenient and reliable platforms for its fast and efficient detection is of paramount importance from security point of view. Herein, amphiphilic fluorescent carbon dots (CDs) were prepared by a simple solvothermal method. CDs exhibit high selectivity and sensitivity on TNP in the polar and apolar solvent and even natural water samples. Moreover, the simple and portable indicator paper can be prepared conveniently and used for sensing TNP visually with high sensitivity and fast response. Research findings obtained from this study would assist in the development of portable devices for the on-site and real-time detection of environmental hazards.


Assuntos
Carbono , Poluentes Ambientais/análise , Substâncias Explosivas/análise , Picratos/análise , Pontos Quânticos , Monitoramento Ambiental , Corantes Fluorescentes
20.
Water Sci Technol ; 79(12): 2260-2270, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31411580

RESUMO

When manually calibrating water quality models, considerable time and attention are required. Hence, developing an automated model that allows for efficient and objective automatic calibration is highly desirable. The QUAL2Kw model calibrates the QUAL2K automatically using a genetic algorithm (GA). This study analyzes auto-calibration results and selects the optimal criterion for each objective function from six performance criteria. Additionally, a multi-objective auto-calibration was conducted using two kinds of performance statistics as the objective function of the GA. The auto-calibration model was applied to the Yeongsan River and the total maximum daily load (TMDL) was established to achieve water quality goals at specific target points of this river. Among the six auto-calibration results based on a single performance criterion, Nash-Sutcliffe model efficiency (NSE) was the best criterion for calculating fitness through auto-calibration. To consider the calibration accuracies of the TMDL target points and the entire river simultaneously, an objective function using multiple performance criteria, specifically the weighted average of the normalized root mean squares error (CV(RMSE)) and the ratio of the RMSE to the standard deviation of the observed data (the RSR), was selected as the final auto-calibration of the model. The model calibration performance was good across the whole region as well as at the target points.


Assuntos
Monitoramento Ambiental , Rios , Calibragem , Modelos Teóricos , Movimentos da Água , Qualidade da Água
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