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1.
Chemosphere ; 282: 131110, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34470162

RESUMO

Fibrous activated carbon has attracted emerging research interests due to its remarkable adsorption performance for volatile organic compounds (VOCs). Though this adsorption behavior for VOCs is closely related to the pore structure on the surface of activated carbon fiber (ACF), few researchers paid attentions to the influence of textural properties of this adsorption process. Especially, cotton-based activated carbon fiber (CACF) for adsorbing benzene pollutant is rarely reported. Herein, in order to develop a high-performance adsorbent for the removal of VOCs pollutants, this work studied the influence of textural properties of CACF on the adsorption of benzene. The results showed that the increase of carbonization temperature would lead to the reduction of mesopores but the increase of micropores for CACF; the embedment of phosphoric acid and its derivatives into the carbon layers contributed to the formation of pore structure for CACF; furthermore, specific surface area of CACF can also be enlarged by increasing the concentration of phosphoric acid. More importantly, it was found that the adsorption capacity of CACF for benzene was strongly dependent on the specific surface area and volume of micropores within CACF because micropores can provide more favorable binding sites. This adsorption process preferred to occur on the wall of micropores, then the accumulated benzene would slowly fill the pores. Interestingly, the decrease of pore size of micropores can unexpectedly improve the affinity of CACF to benzene on the contrary. This work provides a new strategy to develop porous structured ACF materials for the high-performance adsorption of VOCs.


Assuntos
Benzeno , Carvão Vegetal , Adsorção , Fibra de Carbono , Porosidade
2.
Artigo em Inglês | MEDLINE | ID: mdl-33959839

RESUMO

The environment is the most important reservoir for both resistance mechanisms and gene transfer in biological science studies. This study gives a bibliometric overview of studies of "antibiotic resistance" and "Escherichia coli" in the field of "Agricultural and Biological Sciences" from 2015 to 2019 to assess both research trends and scholarly networks in diverse research disciplines. The two keywords of "antibiotic resistance" and "Escherichia coli" were selected to search in the Scopus database. Each review article was categorized into materials, natural waters (i.e., seawater, freshwater) and wastewater, journal name, and quartile in category of the journal, the year of publication, and the country. Bibliometric indicators and visualization maps were utilized to analyse the retrieved data quantitatively and qualitatively. A total of 1376 publications in the field of agricultural and biological sciences over the last 5 years were obtained using the keywords of antibiotic resistance and Escherichia coli. With additional keywords of freshwater and wastewater, 4 and 24 studies were obtained, respectively. Wastewater was found to be the most common working environment for the keywords of antibiotic resistance and Escherichia coli. It is also found that the studies of antibiotic resistance are mainly conducted in wastewater environments, focusing on human and food health. Working under "One Health" consisting of human, animal and agriculture, and environmental health could be the only permanent and effective approach to solving antibiotic resistance-related issues.

3.
Environ Monit Assess ; 192(11): 714, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-33079229

RESUMO

Antibiotic resistance is considered by the countries to be a global health issue and a huge threat to public health. The reduction of resistant microorganisms from water/wastewater is of importance in environmental sciences since they are resistant in the aquatic environment. In this study, a bibliometric analysis of literature from the field of environmental science in water ecosystems from 2015 to 2019 was carried out using the keywords "Antibiotic Resistance (AR)" and "Escherichia coli". Furthermore, using the keywords of "Fresh Water," "Sea Water," and "Waste Water," 155, 52, and 57 studies were discovered, respectively. It is found that 217 studies of the total 2115 studies investigated on AR are mostly performed in the "Waste Water" by considering human health. Given the studies, an up-to-date solution should be proposed since the release of antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs) from wastewater treatment plants needs to be mitigated. For this reason, it is obvious that working on micro and macro ecosystems will increase the probability of solutions in antibiotic resistance. A discussion of removal techniques for coliform bacteria, particularly antibiotic resistant Escherichia coli, was presented. One of the unique values of this study is to offer an innovative solution that removing them by metal-organic frameworks (MOFs) are emerging crystalline hybrid materials. MOFs are used for environmental, biological, and food antimicrobial substances efficiently. Therefore, we can give inspiration to the future studies of antimicrobial resistance removal via adsorption using MOFs as adsorbents. Graphical Abstract.


Assuntos
Ecossistema , Escherichia coli , Bibliometria , Resistência Microbiana a Medicamentos/genética , Monitoramento Ambiental , Humanos
4.
J Am Chem Soc ; 141(6): 2568-2576, 2019 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-30707010

RESUMO

Uremic toxins often accumulate in patients with compromised kidney function, like those with chronic kidney disease (CKD), leading to major clinical complications including serious illness and death. Sufficient removal of these toxins from the blood increases the efficacy of hemodialysis, as well as the survival rate, in CKD patients. Understanding the interactions between an adsorbent and the uremic toxins is critical for designing effective materials to remove these toxic compounds. Herein, we study the adsorption behavior of the uremic toxins, p-cresyl sulfate, indoxyl sulfate, and hippuric acid, in a series of zirconium-based metal-organic frameworks (MOFs). The pyrene-based MOF, NU-1000, offers the highest toxin removal efficiency of all the MOFs in this study. Other Zr-based MOFs possessing comparable surface areas and pore sizes to NU-1000 while lacking an extended aromatic system have much lower toxin removal efficiency. From single-crystal X-ray diffraction analyses assisted by density functional theory calculations, we determined that the high adsorption capacity of NU-1000 can be attributed to the highly hydrophobic adsorption sites sandwiched by two pyrene linkers and the hydroxyls and water molecules on the Zr6 nodes, which are capable of hydrogen bonding with polar functional groups of guest molecules. Further, NU-1000 almost completely removes p-cresyl sulfate from human serum albumin, a protein that these uremic toxins bind to in the body. These results offer design principles for potential MOFs candidates for uremic toxin removal.


Assuntos
Estruturas Metalorgânicas/química , Albumina Sérica Humana/metabolismo , Uremia/metabolismo , Zircônio/química , Adsorção , Cresóis/química , Cresóis/isolamento & purificação , Cresóis/metabolismo , Humanos , Cinética , Modelos Moleculares , Conformação Proteica , Pirenos/química , Ésteres do Ácido Sulfúrico/química , Ésteres do Ácido Sulfúrico/isolamento & purificação , Ésteres do Ácido Sulfúrico/metabolismo
5.
ACS Appl Mater Interfaces ; 11(6): 6097-6103, 2019 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-30707840

RESUMO

The United States Environmental Protection Agency (EPA) recognizes atrazine, a commonly used herbicide, as an endocrine disrupting compound. Excessive use of this agrochemical results in contamination of surface and ground water supplies via agricultural runoff. Efficient removal of atrazine from contaminated water supplies is paramount. Here, the mechanism governing atrazine adsorption in Zr6-based metal-organic frameworks (MOFs) has been thoroughly investigated by studying the effects of MOF linkers and topology on atrazine uptake capacity and uptake kinetics. We found that the mesopores of NU-1000 facilitated rapid atrazine uptake saturating in <5 min and that the pyrene-based linkers offered sufficient sites for π-π interactions with atrazine as demonstrated by the near 100% uptake. Without the presence of a pyrene-based linker, NU-1008, a MOF similar to NU-1000 with respect to surface area and pore size, removed <20% of the exposed atrazine. These results suggest that the atrazine uptake capacity demonstrated by NU-1000 stems from the presence of a pyrene core in the MOF linker, affirming that π-π stacking is responsible for driving atrazine adsorption. Furthermore, NU-1000 displays an exceptional atrazine removal capacity through three cycles of adsorption-desorption. Powder X-ray diffraction and Brunauer-Emmett-Teller surface area analysis confirmed the retention of MOF crystallinity and porosity throughout the adsorption-desorption cycles.

6.
Inorg Chem ; 57(21): 13246-13251, 2018 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-30299939

RESUMO

Isostructural metal-organic frameworks (MOFs) have been prepared from a variety of metal-oxide clusters, including transition metals, lanthanides, and actinides. Experimental and calculated shifts in O-H stretching frequencies for hydroxyl groups associated with the metal-oxide nodes reveal varying electronic properties for these units, thereby offering opportunities to tune support effects for other materials deposited onto these nodes.

7.
Environ Technol ; 32(1-2): 221-30, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21473284

RESUMO

In this study, the characteristics of sonicated waste activated sludge (WAS) originating from a nutrient-removal wastewater treatment plant were investigated and evaluated. Different combinations of power inputs, sonication durations and volumes were used for optimization of the sonication conditions. Ultrasound density levels ranged between 0.32 and 3.2 W/mL. Optimal conditions based on soluble COD concentrations (SCOD) after sonication at different ultrasound density levels and sonication durations (1, 5, 10 and 30 min) were determined. An ultrasonic density of 1.6 W/mL and a sonication time of 30 min were identified as optimal sonication conditions in terms of SCOD concentration. The sludge sonicated under these optimal conditions was further investigated to determine the effect of ultrasound treatment on solubilization of organic matter and volatile solids, particle size and biodegradability. Disruption of the sludge structure was confirmed by the increase in the SCOD by 35.5%, reduction in volatile suspended solids by 26% and reduction in particle size by 85%. The availability of COD fractions of sonicated sludge was also tested with oxygen uptake rate and phosphate release data indicating that using sonicated sludge for both subsequent biological treatment and sludge treatment is promising.


Assuntos
Esgotos/microbiologia , Ultrassom/métodos , Eliminação de Resíduos Líquidos/métodos , Biodegradação Ambiental , Microscopia , Oxigênio/análise , Oxigênio/metabolismo , Tamanho da Partícula , Fosfatos/análise , Fosfatos/metabolismo
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