Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Mar Pollut Bull ; 195: 115473, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37659385

RESUMO

Antibiotics and microplastics (MPs) coexisting as unique environmental contaminants may cause unintended environmental issues. In this study, the adsorption-desorption behaviors of sulfamethoxazole (SMX) on both original and UV-aged MPs were examined. Polyhydroxyalkanoates (PHA) and polyethylene (PE), which represent degradable and refractory MPs, respectively, were chosen as two distinct types of MPs. Furthermore, simulated fish intestinal fluids (SFIF) and simulated mammalian stomach fluids (SMGF) were employed to evaluate the desorption behaviors of SMX from aged MPs. Our findings demonstrate that UV-aging altered the polarity, hydrophilicity, and structure of the MPs. Aged MPs showed a higher adsorption capacity than the original MPs and they have a higher desorption capacity than original MPs in simulated body fluids. PE has a higher SMX desorption capacity in SFIF and the opposite happened in SMGF. Our results highlight the importance of considering the different adsorption-desorption behaviors of antibiotics on MPs when evaluating their environmental impact.

2.
Polymers (Basel) ; 14(19)2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-36236193

RESUMO

Graphene-based membranes have unique nanochannels and can offer advantageous properties for the water desalination process. Although tremendous efforts have been devoted to heightening membrane performance and broadening their application, there is still lack of a systematic literature review on the development and future directions of graphene-based membranes for desalination. In this mini-review, literature published between 2011 and 2022 were analyzed by using the bibliometric method. We found that the major contributors to these publications and the highest citations were from China and the USA. Nearly 80% of author keywords in this analysis were used less than twice, showing the broad interest and great dispersion in this field. The recent advances, remaining gaps, and strategies for future research, were discussed. The development of new multifunctional nanocomposite materials, heat-driven/solar-driven seawater desalination, and large-scale industrial applications, will be important research directions in the future. This literature analysis summarized the recent development of the graphene-based membranes for desalination application, and will be useful for researchers in gaining new insights into this field.

3.
Chemosphere ; 289: 133186, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34883132

RESUMO

Produced water (PW) is the main waste produced by oil and gas industry, and its treatment represents an environmental and economical challenge for governments and the industry itself. Microbial fuel cells (MFC) emerge as an ecofriendly technology able to harvest energy and remove pollutants at the same time, however high internal resistance is a key problem limiting their operating performance and practical application. In this work, a novel continuous up-flow MFC was designed and fed solely using PW under different flowrates. Effects of the different flowrates (0 mL/s, 0.2 mL/s, 0.4 mL/s, and 0.6 mL/s) in power production performance and pollutants removal were analyzed. Our results demonstrated the removal efficiency of all the pollutants improved when flowrate incremented from 0 to 0.4 mL/s (COD: 96%, TDS: 22%, sulfates: 64%, TPH: 89%), but decreased when 0.6 mL/s was applied. The best power density of 227 mW/m2 was achieved in a flowrate of 0.4 mL/s. Similar to the pollutant's removal, the power density increased together with the increment of flowrate and decreased when 0.6 mL/s was used. The reason for the performance fluctuation was the decrement of internal resistance from 80 Ω (batch mode) to 20 Ω (0.4 mL/s), and then the sudden increment to 90 Ω for 0.6 mL/s. A flow simulation revealed that until 0.4 mL/s the flow was organized and helped protons to arrive in the membrane faster, but flowrate of 0.6 mL/s created turbulence which prejudiced the transportation of protons incrementing the internal resistance. Microbial community analysis of the biofilm found that Desulfuromonas, Desulfovibrio and Geoalkalibacter were dominant bacteria in charge of pollutant removal and electricity production. This study can be helpful in guiding the use of continuous-flow MFC for PW treatment, and to accelerate the practical application of MFC technology in oil industry.


Assuntos
Fontes de Energia Bioelétrica , Microbiota , Eletricidade , Eletrodos , Águas Residuárias/análise , Água
4.
Front Microbiol ; 12: 717272, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34659145

RESUMO

Microplastics (MPs) are ubiquitous in the aquatic environment and can be frequently ingested by zooplankton, leading to various effects. Brine shrimp (Artemia parthenogenetica) has an important role in the energy flow through trophic levels in different seawater systems. In this work, the influence of polyethylene (PE) and polystyrene (PS) MPs on the growth of brine shrimp and corresponding changes of gut microbiota were investigated. Our results showed that the MPs remarkably reduced the growth rate of brine shrimp, and the two types of MPs have different impacts. The average body length of brine shrimps was reduced by 17.92 and 14.95% in the PE group and PS group, respectively. MPs are mainly found in the intestine, and their exposure evidently affects the gut microbiota. By using 16S rRNA gene high-throughput sequencing, 32 phyla of bacteria were detected in the intestine, and the microbiome consisted mainly of Proteobacteria, Firmicutes, and Actinobacteria. MPs' exposure significantly increased the gut microbial diversity. For the PE group, the proportion of Actinobacteria and Bacteroidetes increased by 45.26 and 2.73%, respectively. For the PS group, it was 54.95 and 1.27%, respectively. According to the analysis on genus level, the proportions of Ponticoccus, Seohaeicola, Polycyclovorans, and Methylophaga decreased by 46.38, 1.24, 1.07, and 2.66%, respectively, for the PE group and 57.87, 1.43, 0.88, and 2.24%, respectively, for the PS group. In contrast, the proportions of Stappia, Microbacterium, and Dietzia increased by 1.12, 23.27, and 11.59%, respectively, for the PE group, and 1.09, 3.79, and 42.96%, respectively, for the PS group. These experimental results demonstrated that the ingestion of MPs by brine shrimp can alter the composition of the gut microbiota and lead to a slow growth rate. This study provides preliminary data support for understanding the biotoxicity of MPs to invertebrate zooplankton and is conducive to the further risk assessment of MP exposure.

5.
Chemosphere ; 285: 131428, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34237499

RESUMO

Disposal of the high volume of produced water (PW) is a big challenge to the oil and gas industry. High cost of conventional treatment facilities, increasing energy prices and environmental concern had focused governments and the industry itself on more efficient treatment methods. Bioelectrochemical system (BES) has attracted the attention of researchers because it represents a sustainable way to treat wastewater. This is the first review that summarizes the progress done in PW-fed BESs with a critical analysis of the parameters that influence their performances. Inoculum, temperature, hydraulic retention time, external resistance, and the use of real or synthetic produced water were found to be deeply related to the performance of BES. Microbial fuel cells are the most analyzed BES in this field followed by different types of microbial desalination cells. High concentration of sulfates in PW suggests that most of hydrocarbons are removed mainly by using sulfates as terminal electron acceptor (TEA), but other TEAs such as nitrate or metals can also be employed. The use of real PW as feed in experiments is highly recommended because biofilms when using synthetic PW are not the same. This review is believed to be helpful in guiding the research directions on the use of BES for PW treatment, and to speed up the practical application of BES technology in oil and gas industry.


Assuntos
Fontes de Energia Bioelétrica , Água , Indústria de Petróleo e Gás , Tecnologia , Águas Residuárias/análise
6.
Nanomaterials (Basel) ; 11(1)2021 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-33466815

RESUMO

In this work, reduced graphene oxide (rGO) nanocomposites doped with nitrogen (N), sulfur (S) and transitional metal (Ni, Co, Fe) were synthesized by using a simple one-step in-situ hydrothermal approach. Electrochemical characterization showed that rGO-NS-Ni was the most prominent catalyst for glucose oxidation. The current density of the direct glucose alkaline fuel cell (DGAFC) with rGO-NS-Ni as the anode catalyst reached 148.0 mA/cm2, which was 40.82% higher than the blank group. The DGAFC exhibited a maximum power density of 48 W/m2, which was more than 2.08 folds than that of blank group. The catalyst was further characterized by SEM, XPS and Raman. It was speculated that the boosted performance was due to the synergistic effect of N, S-doped rGO and the metallic redox couples, (Ni2+/Ni3+, Co2+/Co3+ and Fe2+/Fe3+), which created more active sites and accelerated electron transfer. This research can provide insights for the development of environmental benign catalysts and promote the application of the DGAFCs.

7.
Zhongguo Zhong Yao Za Zhi ; 44(11): 2397-2402, 2019 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-31359669

RESUMO

The purpose of this paper is to study the use rules of drugs for lung diseases in internal medicine department of Xin'an Wang's family, discuss the compatibility of common drugs for lung diseases, guide clinical application, and inherit Xin'an medicine. By retrospective study on lung diseases cases in Wang's internal medicine works, the lung diseases and use frequency of common drugs treated by Wang's medicine were counted, and the systematic clustering and association rule analysis of common drugs were conducted by using SPSS Statistic 20 and SPSS Modeler 18.0, respectively. The results showed that asthma, cold and cough were the main lung diseases treated by Wang's medicine, and the commonly used medicines included antitussive and antiasthmatic drugs, spleen-invigorating and dampness-removing drugs, and expectorants. The medicine taste was mainly bitter, pungent and sweet, with cold and warm properties in a balanced way, without severely cold or hot herbs, mainly attributing to the lung and stomach meridians. In clustering analysis, 10 drug combinations were obtained; association analysis showed that two, three, four association rules respectively had 11, 21, and 10 groups, and each drug group had 11, 16, and 5 items. Core combinations: Poria, Armeniacae Semen Amarum, Asteris Radix et Rhizome, Coicis Semen, Farfarae Flos, Dendrobii Caulis, Perilla Frutescens, Stemonae Radix, Citri Reticulatae Pericarpium, Cynanchi Stauntonii Rhizome et Radix, Meretricis Concha Cyclinae Concha, Belamcandae Rhizoma, and Pinelliae Rhizome. Xin'an Wang's medicine paid attention to the lung nature when treating lung diseases. Lung is a delicate organ, not resistant to coldness or heat, so severely cold or hot herbs shall not be used, and the clear and light drugs with functions of dispersing lung Qi, clearing phlegm evil, strengthening spleen, eliminating phlegm, and relieving cough and asthma are often used. Lung deficiency is a kind of deficiency of Qi and Yin, so both Qi and Yin shall be regulated. Deficiency of Yin would burn the lung and make the lung collaterals blocked. In this case, the lung collaterals shall be dredged for hemostasis. Long time of lung deficiency would hinder the distribution of body fluid, and lung shall be regulated to dissipate phlegm.


Assuntos
Mineração de Dados , Medicamentos de Ervas Chinesas/uso terapêutico , Pneumopatias/tratamento farmacológico , Humanos , Medicina Tradicional Chinesa , Meridianos , Estudos Retrospectivos
8.
Environ Technol ; 39(24): 3228-3237, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28866963

RESUMO

The biochemical oxygen demand (BOD) is widely used for the evaluation of water and wastewater quality. However, the conventional method to measure BOD is time-consuming and requires complicated processes. In this study, a Microbial fuel cell (MFC)-based BOD sensor was developed by using low-cost activated carbon as the cathode catalyst. The sensor was calibrated with an aerated nutrient medium containing sodium acetate as the BOD source. When the sensor was operated with an external resistance of 1 K Ω, linear correlation (R2 = 0.9965) was obtained for BOD concentrations ranging from 80 to 1280 mg/L in a reaction time of 50 h. Besides acetate, glucose/glutamic acid (GGA) and ethanol could also be analyzed by the sensor. In a low concentration range (200 mg/L), the relationship between GGA solution concentration and output voltage was in accord with Monod growth kinetics.


Assuntos
Fontes de Energia Bioelétrica , Técnicas Biossensoriais , Eletrodos , Oxigênio , Águas Residuárias
9.
Se Pu ; 34(2): 189-93, 2016 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-27382725

RESUMO

New methods were developed for the determination of succinic acid in desvenlafaxine succinate (DVS) by high performance ion-exclusion chromatography (HPIEC) and high performance ion-exchange chromatography (HPIC). HPIEC and HPIC methods were used separately to determinate the succinic acid in DVS. With HPIEC, the sample was diluted with 2. 50 x 10(-3) mol/L sulfuric acid solution and filtrated by 0. 22 µm polyether sulfone filter membrane, and then analyzed by HPIEC directly without any further pretreatment. The analytical column was Phenomenex Rezex ROA-organic Acid H+(8%) (300 mmx7. 8 mm). The mobile phase was 2. 50x10(-3) mol/L sulfuric acid solution at the flow rate of 0. 5 mL/min. The column temperature was set at 40 °C, and the detection wavelength was 210 nm. The injection volume was 10 KL. The assay was quantified by external standard method. With HPIC, the sample was diluted with ultrapure water and filtrated by 0. 22 µm polyether sulfone filter membrane, and then analyzed by HPIC directly without any further pretreatment. The analytical column was Dionex IonPac AS11-HC (250 mm x 4 mm) with a guard column IonPacAG11-HC (50 mm x 4 mm). Isocratic KOH elute generator was used at the flow rate of 1. 0 mL/min. The detection was performed by a Dionex suppressed (DIONEX AERS 500 4-mm) conductivity detector. The injection volume was 10 µL. The content computation was performed with peak area external reference method. The results of HPIEC method for succinic acid were 28. 8%, 28. 9% and 28. 9%, while the results of HPIEC method were 28. 2%, 28. 6% and 28. 6%. The results of HPIEC and HPIC methods were not significantly different. The two methods can both be used to determine the contents of succinic acid in DVS. The surveillance analytical method should be chosen according to the situation.


Assuntos
Cromatografia por Troca Iônica , Succinato de Desvenlafaxina/análise , Ácido Succínico/análise , Ácidos , Cromatografia em Gel , Soluções , Ácidos Sulfúricos , Água
10.
Se Pu ; 32(11): 1275-9, 2014 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-25764665

RESUMO

A new method was developed for the determination of adenosine disodium triphos- phate (ATP-Na2 ) and its related substances in ATP-Na2 preparation by ion chromatography (IC). The sample was diluted with ultrapure water and filtrated by 0.22 µm polyether sulfone filter membrance, and then analyzed by IC directly without any more pretreatment. The analysis was performed on a Dionex IonPac AS11-HC column (250 mm x 4 mm) and a guard column Ion-Pac AG11-HC (50 mm x 4 mm). A KOH eluent generator cartridge was used for gradient elution at the flow rate of 1.0 mL/min. The detection was performed by a Dionex suppressed (Dionex AERS 500 4-mm) conductivity detector. The injection volume was 10 µL. The assay was quantitatively completed by external standard method and the related substances were calculated with correction factors. The linear ranges of the method for ATP-Na2, adenosine disodium diphosphate (ADP-Na2) and adenosine disodium monophosphate (AMP-Na2) were 0.000 146-1.83 g/L (r = 0.9997), 0.000484-1.51 g/L (r = 0.9996) and 0.000426-0.804 g/L (r = 0.9999), respectively. The average recoveries of ATP-Na2 were 96.50%, 96.57% and 96.77% at three spiked levels. The limits of quantitation (S/N = 10) of ATP-Na2, ADP-Na2 and AMP-Na2 were 1.5 ng, 4.8 ng, 4.3 ng, and the limits of detection (S/N = 3) were 0.58 ng, 1.21 ng, 1.28 ng, respectively. The results demonstrated that the system has the advantages of high sensitivity, facile automation and simple sample pretreatment. The method is suitable for the quality control of adenosine disodium triphosphate preparations.


Assuntos
Trifosfato de Adenosina/química , Trifosfato de Adenosina/síntese química , Cromatografia por Troca Iônica , Análise de Componente Principal , Água
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...