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1.
Chemosphere ; 351: 141204, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38237778

RESUMO

Priestia sp. WW1 was isolated from a uranium-contaminated mining soil and identified. The uranium removal characteristics and mechanism of Priestia sp. WW1 were investigated. The results showed that the removal efficiency of uranium decreased with the increase of initial uranium concentration. When the uranium initial concentration was 5 mg/L, the uranium removal efficiency achieved 92.1%. The increase of temperature could promote the uranium removal. Carbon source could affect the removal rate of uranium, which was the fastest when the methanol was used as carbon source. The solution pH had significant effect on the uranium removal efficiency, which reached the maximum under solution pH 5.0. The experimental results and FTIR as well as XPS demonstrated that Priestia sp. WW1 could remove uranium via both adsorption and reduction. The common chloride ions, sulfate ions, Mn(II) and Cu(II) enhanced the uranium removal, while Fe(III) depressed the uranium removal. The Priestia sp. WW1 could effectively remove the uranium in the actual mining groundwater, and the increase of initial biomass could improve the removal efficiency of uranium in the actual mining groundwater. This study provided a promising bacterium for uranium remediation in the groundwater.


Assuntos
Bacillaceae , Água Subterrânea , Urânio , Urânio/análise , Compostos Férricos , Carbono , Íons , Solo , Adsorção
2.
Environ Res ; 220: 115224, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36626948

RESUMO

A storm-drain inlet is an important link in the transport of microplastic pollutants in urban rainwater runoff. In three functional districts (agricultural, commercial, and residential) from Beijing South 2nd Ring Road to South 6th Ring Road, microplastics in storm-drain inlet sediments were analyzed for abundance and characteristics. The abundance of microplastics in the collected samples ranged from 1121 ± 247 items kg-1 to 7393 ± 491 items kg-1. Among the sample areas, the commercial area had the greatest abundance (11094 items kg-1), while the agricultural area had the lowest (833 items kg-1). The microplastics in the samples were mainly fragments, accounting for 50.4%. Microplastics of less than 1 mm accounted for 74.8%. The color of microplastics was diverse, with colored MPs accounting for 26% and transparent ones for 47.8%. Most of the polymers detected were PET, PS, and PP, which are the most commonly used polymers. Overall, the results provide baseline data on microplastic pollution and its associated risks, in addition to guidelines for controlling runoff pollution.


Assuntos
Microplásticos , Poluentes Químicos da Água , Plásticos , Pequim , Baías , Sedimentos Geológicos , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , Demografia
3.
Sensors (Basel) ; 22(10)2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35632027

RESUMO

Carton detection is an important technique in the automatic logistics system and can be applied to many applications such as the stacking and unstacking of cartons and the unloading of cartons in the containers. However, there is no public large-scale carton dataset for the research community to train and evaluate the carton detection models up to now, which hinders the development of carton detection. In this article, we present a large-scale carton dataset named Stacked Carton Dataset (SCD) with the goal of advancing the state-of-the-art in carton detection. Images were collected from the Internet and several warehouses, and objects were labeled for precise localization using instance mask annotation. There were a total of 250,000 instance masks from 16,136 images. Naturally, a suite of benchmarks was established with several popular detectors and instance segmentation models. In addition, we designed a carton detector based on RetinaNet by embedding our proposed Offset Prediction between the Classification and Localization module (OPCL) and the Boundary Guided Supervision module (BGS). OPCL alleviates the imbalance problem between classification and localization quality, which boosts AP by 3.1∼4.7% on SCD at the model level, while BGS guides the detector to pay more attention to the boundary information of cartons and decouple repeated carton textures at the task level. To demonstrate the generalization of OPCL for other datasets, we conducted extensive experiments on MS COCO and PASCAL VOC. The improvements in AP on MS COCO and PASCAL VOC were 1.8∼2.2% and 3.4∼4.3%, respectively.


Assuntos
Compostos Orgânicos Voláteis
4.
Environ Technol ; 42(9): 1313-1325, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31543028

RESUMO

In this study, an efficient adsorption and reusable magnetic ligand material (Fe3O4@Chitosan-EDTA) was synthesized by binding EDTA dianhydride onto magnetic chitosan, and it was employed in removal of Co(II) from aqueous solution. The maximum adsorption capacity of Co(II) onto Fe3O4@CS-EDTA was 48.78 mg/g at pH = 5 (303 K), which is much higher than that of Fe3O4@Chitosan as well as chitosan. The kinetics of Co(II) on the Fe3O4@CS-EDTA was consistent with the pseudo-second-order model. The equilibrium data were better fit with the Langmuir isothermal model than with the Freundlich isothermal model, suggesting that the adsorption mechanism was chemical monolayer homogeneous adsorption. The thermodynamic data showed that the sorption of Co(II) was spontaneous. Furthermore, after four cycles, the adsorption capacity of Co(II) onto the Fe3O4@CS-EDTA still retained 84.5% of the capacity of the fresh adsorbent, indicating that Fe3O4@CS-EDTA can be considered a promising recyclable adsorbent to remove heavy-metal ions from wastewater.


Assuntos
Quitosana , Poluentes Químicos da Água , Purificação da Água , Adsorção , Ácido Edético , Concentração de Íons de Hidrogênio , Cinética , Fenômenos Magnéticos
5.
Environ Sci Pollut Res Int ; 27(3): 2588-2598, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31832938

RESUMO

Magnetic phosphorylated chitosan composite (P-MCS), an excellent adsorbent for Co(II), was synthesized in this experiment via a facile fabrication. Its removal efficiency was improved by optimizing pH, contact time, and initial concentration. The adsorption isotherms and kinetic models of Co(II) by P-MCS followed the Langmuir model and the pseudo-second-order model, respectively. However, the rate of adsorption was also affected by intragranular diffusion. The maximum adsorption capacity was 46.1 mg g-1 for Co(II). The results of spectroscopic analysis also indicated that good adsorption performance of Co(II) mainly depends on surface chelation between functional groups and metal ions. The saturation magnetic susceptibilities of P-MCS and P-MCS-Co were 22.29 emu g-1 and 18.18 emu g-1, respectively. The excellent magnetic properties of P-MCS enabled the easy achievement of solid-liquid separation via the use of an external magnetic field. In complex aqueous solutions, K+, Na+, Ca2+, and Mg2+ have less influence on P-MCS adsorption Co(II), but the adsorption capacity on Co(II) is still good. This study shows the feasibility of using P-MCS to treat wastewater containing Co(II).


Assuntos
Quitosana , Cobalto/química , Poluentes Químicos da Água , Purificação da Água/métodos , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Fenômenos Magnéticos , Água
6.
Artigo em Inglês | MEDLINE | ID: mdl-25333103

RESUMO

Identifying neutrophils lays a crucial foundation for diagnosing acute inflammation diseases. But, such computerized methods on the commonly used H&E staining histology tissue images are lacking, due to various inherent difficulties of identifying cells in such image modality and the challenge that a considerable portion of neutrophils do not have a "textbook" appearance. In this paper, we propose a new method for identifying neutrophils in H&E staining histology tissue images. We first segment the cells by applying iterative edge labeling, and then identify neutrophils based on the segmentation results by considering the "context" of each candidate cell constructed by a new Voronoi diagram of clusters of other neutrophils. We obtain good performance compared with two baseline algorithms we constructed, on clinical images collected from patients suspected of having inflammatory bowl diseases.


Assuntos
Inteligência Artificial , Amarelo de Eosina-(YS) , Hematoxilina , Doenças Inflamatórias Intestinais/patologia , Microscopia/métodos , Neutrófilos/patologia , Reconhecimento Automatizado de Padrão/métodos , Algoritmos , Células Cultivadas , Corantes , Humanos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Coloração e Rotulagem
7.
J Hazard Mater ; 143(1-2): 2-7, 2007 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-17293039

RESUMO

Sewage sludge is unwanted residual solid wastes generated in wastewater treatment and its management is one of the most critical environmental issues of today. The treatment and disposal of sludge contribute a considerable proportion of the cost for running a wastewater treatment plant. The increasing amount of sewage sludge and more and more legislative regulation of its disposal have stimulated the need for developing new technologies to process sewage sludge efficiently and economically. One ideal consideration is to recycle it after proper treatment. Radiation technology is regarded to be a promising alternative for its high efficiency in pathogen inactivation, organic pollutants oxidation, odor nuisance elimination and some other characteristics enhancement, which will facilitate the down-stream process of sludge treatment and disposal. Here we present a brief review of application of radiation technology on sewage sludge processing. Some basic information of two currently available irradiation systems and fundamental radiation chemistry are introduced firstly; then the world-wide application of this promising technology is reviewed; various effects of radiation on sludge is discussed in detail; and some concluding remarks are given and some future directions are also proposed.


Assuntos
Radiação , Gerenciamento de Resíduos/métodos
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