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1.
J Sep Sci ; 47(9-10): e2300925, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38726740

RESUMO

Deep eutectic solvents (DESs), as a new type of eco-friendly solvent, have attracted increasing attention on the extraction and separation of flavonoid compounds from various samples, owing to their excellent properties such as biodegradability and ease of handling with very low toxicity. This article provides a status review of the applications of DESs in the extraction of flavonoids, including the introduction of flavonoid compounds, the properties and superiority of DESs, and extraction methods (ultrasonic-assisted extraction, heating reflux extraction, matrix solid-phase dispersion, and solid-phase extraction). Finally, prospects and challenges in the application of DESs on extraction and separation are extensively elucidated and critically reviewed.


Assuntos
Solventes Eutéticos Profundos , Flavonoides , Extração em Fase Sólida , Flavonoides/isolamento & purificação , Flavonoides/química , Solventes Eutéticos Profundos/química , Solventes/química
2.
Transl Cancer Res ; 13(3): 1394-1405, 2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38617517

RESUMO

Background: Lung cancer (LC) is a leading cause of cancer-associated mortality worldwide, with high incidence and mortality rates. Ly6/PLAUR domain containing 3 (LYPD3) is a tumorigenic and highly glycosylated cell surface protein that has been rarely reported in LC. This study aimed to explore the prognostic role and immune cell infiltration of LYPD3 in LC. Methods: We used ExoCarta, a database of exosomal proteins and RNA, to select exosomes in LC. The Tumor Immune Estimation Resource (TIMER) and Human Protein Atlas (HPA) databases were utilized to compare the expression of LYPD3 in LC. We applied Gene Expression Profiling Interactive Analysis 2 (GEPIA2) and Kaplan-Meier (KM) plotter to evaluate the prognostic prediction performance of LYPD3. Biological processes (BPs), Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses, and gene set enrichment analysis (GSEA) analyses were performed to illustrate the possible role of LYPD3 in LC. The correlations between LYPD3 and immune cell infiltration were explored using Tumor and Immune System Interaction Database (TISIDB), GEPIA2, and TIMER. R software was used for statistical analysis and mapping. Results: A total of 904 exosome molecules were screened in LC. Further analysis showed that the up-regulation of LYPD3 in these 904 exosome molecules was associated with poor prognosis in LC. Pan-cancer analyses revealed that the expression of LYPD3 varied in many cancers, particularly in LC. Clinical correlation analysis indicated that LYPD3 was associated with stage and T classification in LC. We observed that LYPD3 co-expression genes were associated with cell cycle, DNA replication, proteasome, and regulation of the actin cytoskeleton by GSEA. Moreover, LYPD3 was associated with immune modulators. Immunophenoscores (IPS) and IPS-CTLA4 were significantly different between the high LYPD3 group and low LYPD3 group. Additionally, the median half maximal inhibitory concentration (IC50) of bexarotene, cyclopamine, etoposide, and paclitaxel in LYPD3 high group was significantly lower than that in LYPD3 low group. Conclusions: LYPD3 is involved in many BPs of LC, such as regulating immune cell infiltration and affecting prognosis. Therefore, LYPD3 may have potential value as a biomarker for prognosis and immunotherapy in LC.

5.
Ecotoxicol Environ Saf ; 266: 115588, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37839193

RESUMO

High concentration of ammonia poses a common threat to the healthy breeding of marine aquaculture organisms. Since aquaculture water is rich in organic matter, heterotrophic nitrifying bacteria might play a crucial role in ammonia removal. However, their roles in ammonia oxidation remain unknown. Here, we report a novel strain isolated from shrimp aquaculture seawater, identified as Sneathiella aquimaris 216LB-ZA1-12T, capable of heterotrophic nitrification. It is the first characterized heterotrophic nitrifier of the order Sneathiellales in the class Alphaproteobacteria. It exhibits high activity in heterotrophic nitrification, removing nearly 94% of ammonium-N under carbon-constrained conditions in 8 days with no observed nitrite accumulation. The heterotrophic nitrification pathway, inferred based on detection and genomic data was as follows: NH4+→NH2OH→NO→NO2-→NO3-. While this pathway aligns with the classical nitrification pathway, while the significant difference lies in the absence of classical HAO and HOX encoding genes in the genome, which is common in heterotrophic nitrifying bacteria. In summary, this bacterium is not only valuable for studying the nitrifying mechanism, but also holds potential for practical applications in ammonia removal in marine aquaculture systems and saline wastewater.


Assuntos
Alphaproteobacteria , Nitrificação , Desnitrificação , Amônia/metabolismo , Aerobiose , Nitritos/metabolismo , Bactérias/metabolismo , Processos Heterotróficos , Aquicultura , Água do Mar/microbiologia , Alphaproteobacteria/metabolismo , Nitrogênio/metabolismo
6.
Int J Syst Evol Microbiol ; 73(20)2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37801073

RESUMO

Two Gram-stain-negative, non-motile, non-spore-forming, strictly aerobic and rod-shaped bacterial strains, CMA-7T and CAA-3, were isolated from surface seawater samples collected from the western Pacific Ocean. Phylogeny of 16S rRNA gene sequences indicated they were related to the genera Galbibacter and Joostella and shared 95.1, 90.9 and 90.8% sequence similarity with G. mesophilus Mok-17T, J. marina DSM 19592T and G. marinus ck-I2-15T, respectively. Phylogenomic analysis showed that the two strains, together with the members of the genera Galbibacter and Joostella, formed a monophyletic clade that could also be considered a monophyletic taxon. This distinctiveness was supported by amino acid identity and percentage of conserved proteins indices, phenotypic and chemotaxonomic characteristics and comparative genomics analysis. Digital DNA‒DNA hybridization values and average nucleotide identities between the two strains and their closest relatives were 18.0-20.8 % and 77.7-79.3 %, respectively. The principal fatty acids were iso-C15 : 0, iso-C17 : 0 3-OH, iso-C15 : 1 G, Summed Feature 3 (C16 : 1 ω7c/C16 : 1 ω6c or C16 : 1 ω6c/C16 : 1 ω7c), Summed Feature 9 (iso-C17 : 1 ω9c or C16 : 0 10-methyl), and C15 : 0 3-OH. The predominant respiratory quinone was MK-6. The polar lipids were phosphatidylethanolamine, aminolipid, aminophospholipid, phospholipid, phosphoglycolipid, glycolipid and unknown polar lipid. The genomic DNA G+C content of strains CMA-7T and CAA-3 was both 38.4 mol%. Genomic analysis indicated they have the potential to degrade cellulose and chitin. Based on the polyphasic evidence presented in this study, the two strains represent a novel species within the genus Galbibacter, for which the name Galbibacter pacificus sp. nov. is proposed. The type strain is CMA-7T (=MCCC M28999T = KCTC 92588T). Moreover, the transfer of Joostella marina to the genus Galbibacter as Galbibacter orientalis nom. nov. (type strain En5T = KCTC 12518T = DSM 19592T=CGMCC 1.6973T) is also proposed.


Assuntos
Ácidos Graxos , Água do Mar , Ácidos Graxos/química , RNA Ribossômico 16S/genética , Oceano Pacífico , DNA Bacteriano/genética , Análise de Sequência de DNA , Filogenia , Composição de Bases , Técnicas de Tipagem Bacteriana , Água do Mar/microbiologia
7.
Dalton Trans ; 52(32): 11035-11041, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37526042

RESUMO

In recent years, a variety of adsorbents have been developed for Hg2+ removal. However, these adsorbents are unsatisfactory for adsorption due to narrow and irregular pore channels or poor adsorption capacity and low stability. Therefore, it is worth exploring a porous Hg2+ adsorbent material with high adsorption performance and stability. In this study, a benzothiadiazole-based nonbranching functionalized covalent organic framework (COF) material (TPS-COF) by one-step synthesis was reported, which exhibited a high specific surface area of 1564 m2 g-1, high crystallinity and stability attributed to its high conjugated linkage structure of benzothiadiazole. In addition, due to the rich S and N elements of the benzothiadiazole unit, it exhibited excellent adsorption performance on Hg2+, including excellent adsorption amount (1040 mg g-1), high initial adsorption rate (448 mg g-1 min-1) and very short adsorption equilibrium time (10 min), with an efficient removal rate of Hg2+ in the pH range of 2-8. After desorption, the TPS-COF still retained good pore stability, adsorption capacity, and reusability. Such a one-step synthetic unbranched functionalization strategy provides further insights to achieve a good balance between the high crystallinity, functionality and stability of COFs.

8.
Chemosphere ; 340: 139696, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37557996

RESUMO

The magnetic Fe3O4/bamboo-based activated carbon/Zr-based metal-organic frameworks composite (Fe3O4/BAC/UiO-66) was prepared by hydrothermal method. The as-prepared material was analyzed via TEM, XRD, FT-IR, BET-BJH, VSM and XPS techniques, the results showed that it had good dispersion and magnetic separation capacity (Ms = 44.06 emu∙g-1). Then, the adsorption properties of materials for bisphenol A (BPA) were studied. The results revealed that the removal efficiency of 50 mg·L-1 BPA by 0.1 g of adsorbent can reach 87.18-95% in a wide pH range. Langmuir isotherm model and pseudo-second-order kinetic well fitted the adsorption data. The thermodynamic data indicated that the adsorption process was spontaneous and endothermic. Moreover, BAC as a supporter and UiO-66 as the functional part in the ternary composite may have a synergistic effect, which was beneficial for the removal of contaminants. The Fe3O4/BAC/UiO-66 can be simply separated from the water using its strong magnetism after finish adsorption process, which effectively avoids secondary contamination.


Assuntos
Carvão Vegetal , Poluentes Químicos da Água , Espectroscopia de Infravermelho com Transformada de Fourier , Adsorção , Fenômenos Magnéticos , Poluentes Químicos da Água/análise , Cinética
9.
Chemosphere ; 338: 139451, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37451632

RESUMO

An off-on fluorescent probe (NS-CDs-AgNPs) was synthesized based on a one-pot microwave process by utilizing N, S co-doping carbon dots (NS-CDs) and silver nitrate as precursors. The significant peak of NS-CDs-AgNPs at 393 nm in ultraviolet spectrum indicated silver nanoparticle (AgNPs) were successfully synthesized. A faint blue fluorescence emission (442 nm) was displayed when excited NS-CDs-AgNPs at 371 nm. A remarkable fluorescence recovery was observed upon adding of trance Hg2+, whereas the other heavy metal ions did not elicit this response. The reason for this phenomenon was revealed in this work that a spontaneous redox reaction occurred between NS-CDs-AgNPs and Hg2+, which leaded to the formation of NS-CDs-Agn-2NPsHg complexes. On the basis of this mechanism, a new off-on fluorescent analytical method was constructed for Hg2+ detection with linear range of 10-400 nM (R2 = 0.9941), and the detection limit (LOD) of 5.16 nM. Additionally, satisfactory recovery (90.28%-106.13%) and the relative standard deviation (RSD) (RSD<5.21%) were obtained in water sample detection. More importantly, the NS-CDs-AgNPs exhibited lower cytotoxicity and better biocompatibility, indicating a huge potential in cell imaging and clinical medicine.


Assuntos
Mercúrio , Nanopartículas Metálicas , Pontos Quânticos , Corantes Fluorescentes , Carbono , Micro-Ondas , Espectrometria de Fluorescência/métodos , Limite de Detecção , Prata
10.
Chemosphere ; 338: 139399, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37423411

RESUMO

In the present study, Ni-UiO-66 was synthesized to improve the adsorption efficiency of tetracycline (TC) in wastewater treatment. To this end, nickel doping was performed in the preparation process of UiO-66. The synthesized Ni-UiO-66 was characterized by XRD, SEM and EDS, BET, FTIR, TGA, and XPS for obtaining the lattice structure, surface topography, specific surface area, surface functional groups, and thermostability. More specifically, Ni-UiO-66 has a removal efficiency and adsorption capacity of up to 90% and 120 mg g-1, respectively, when used to treat TC. The presence of ions HCO3-, SO42-, NO3- and PO43- slightly affects the TC adsorption. A 20 mg L-1 humic acid reduces the removal efficiency from 80% to 60%. The performed analyses revealed that Ni-UiO-66 had similar adsorption capacity in wastewater with different ion strengths. The variation of adsorption capacity with the adsorption time was fitted using a pseudo-second-order kinetic equation. Meanwhile, it is found that the adsorption reaction occurs only on the monolayer of the UiO-66 surface so the adsorption process can be simulated using the Langmuir isotherm model. The thermodynamic analysis indicates that the adsorption of TC is an endothermic reaction. Electrostatic attraction, hydrogen-bond interaction, and π-π interaction might be the main reasons for the adsorption. The synthesized Ni-UiO-66 has well adsorption capacity and stable structure. Accordingly, it is expected to achieve a good prospect in industrial applications and wastewater treatment plants.


Assuntos
Águas Residuárias , Poluentes Químicos da Água , Níquel , Poluentes Químicos da Água/química , Tetraciclina , Antibacterianos/química , Termodinâmica , Adsorção , Cinética , Concentração de Íons de Hidrogênio
11.
Chemosphere ; 336: 139241, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37330066

RESUMO

Excessive phosphorus (P) and ammonia nitrogen (NH3-N) in water bodies can lead to eutrophication of the aquatic environment. Therefore, it is important to develop a technology that can efficiently remove P and NH3-N from water. Here, the adsorption performance of cerium-loaded intercalated bentonite (Ce-bentonite) was optimized based on single-factor experiments using central composite design-response surface methodology (CCD-RSM) and genetic algorithm-back propagation neural network (GA-BPNN) models. Based on the determination coefficient (R2), mean absolute error (MAE), mean square error (MSE), mean absolute percentage error (MAPE), and root mean square error (RMSE), the GA-BPNN model was found to be more accurate in predicting adsorption conditions than the CCD-RSM model. The validation results showed that the removal efficiency of P and NH3-N by Ce-bentonite under optimal adsorption conditions (adsorbent dosage = 1.0 g, adsorption time = 60 min, pH = 8, initial concentration = 30 mg/L) reached 95.70% and 65.93%. Furthermore, based on the application of these optimal conditions in simultaneous removal of P and NH3-N by Ce-bentonite, pseudo-second order and Freundlich models were able to better analyze adsorption kinetics and isotherms. It is concluded that the optimization of experimental conditions by GA-BPNN has some guidance and provides a new approach to explore adsorption performance after optimizing the conditions.


Assuntos
Cério , Poluentes Químicos da Água , Fósforo , Bentonita , Amônia , Adsorção , Redes Neurais de Computação , Cinética , Nitrogênio , Concentração de Íons de Hidrogênio
12.
Artigo em Inglês | MEDLINE | ID: mdl-36795459

RESUMO

A novel marine bacterium designated strain PHK-P5T was isolated from a sea anemone (Actinostolidae sp. 1). Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain PHK-P5T belonged to the genus Sneathiella. The bacterium was Gram-stain-negative, aerobic, oxidase- and catalase- positive, oval- to rod-shaped, and motile. Growth was observed at pH 6.0-9.0, salinities of 2.0-9.0 % and temperatures of 4-37 °C. The G+C content of the chromosomal DNA was 49.2 %. The respiratory quinone was determined to be Q-10. The principal fatty acids of strain PHK-P5T were C19 : 0cyclo ω8c (25.19 %), C16 : 0 (22.76 %), summed feature 8 (C18 : 1 ω7c/ω6c; 16.14 %), C14 : 0 (8.81 %), C17 : 0cyclo (8.10 %), summed feature 2 (C12 : 0 aldehyde and/or unknown 10.928; 7.19 %) and C18 : 1 ω7c 11-methyl (5.03 %). The major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol. The average nucleotide identity and digital DNA-DNA hybridization values among the genomes of strain PHK-P5T and the reference strains were 68.7-70.9 % and 17.4-18.1 %, respectively. The combined genotypic and phenotypic data showed that strain PHK-P5T represents a novel species within the genus Sneathiella, for which the name Sneathiella marina sp. nov. is proposed, with the type strain PHK-P5T (=MCCC M21824T=KCTC 82924T).


Assuntos
Alphaproteobacteria , Anêmonas-do-Mar , Animais , Ácidos Graxos/química , Fosfolipídeos/química , Água do Mar/microbiologia , Anêmonas-do-Mar/genética , Filogenia , Oceano Pacífico , RNA Ribossômico 16S/genética , DNA Bacteriano/genética , Composição de Bases , Técnicas de Tipagem Bacteriana , Análise de Sequência de DNA , Ubiquinona/química
13.
Environ Sci Pollut Res Int ; 30(44): 98881-98894, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35987850

RESUMO

A low-cost functionalization method was used to treat diatomite, and an efficient adsorbent for ammonia nitrogen was prepared by optimizing the functionalization conditions. The functionalized diatomite (DTCA-Na) was characterized by SEM, EDS, BET, XRD, FT-IR, and TG. The results demonstrate that DTCA-Na has excellent adsorption performance after being modified with H2SO4 (60.00 wt.%), NaCl (5.00 wt.%), and calcination at 400 °C for 2 h. While studying the effect of adsorption factors on the removal of ammonia nitrogen, the kinetic and thermodynamic behaviors in the adsorption process were discussed. The removal efficiency of the simulated wastewater with the initial ammonia nitrogen concentration of 10.00 mg L-1 by the DTCA-Na was more than 80% when the contact time was 60 min, pH was 6-10, the dosage of adsorbent was 1.00 g, and the temperature was 25 °C. The adsorption process of ammonia nitrogen was conformed to the pseudo-first-order and Langmuir isothermal model. The removal efficiency of ammonia nitrogen was still above 80% after 5 times adsorption-desorption experiments. The DTCA-Na has a brighter prospect of application in the field of ammonia nitrogen wastewater treatment due to its excellent adsorption performance and low-cost advantage.


Assuntos
Águas Residuárias , Poluentes Químicos da Água , Amônia/química , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água/química , Nitrogênio/química , Adsorção , Cinética , Concentração de Íons de Hidrogênio
14.
Polymers (Basel) ; 14(15)2022 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-35956733

RESUMO

In this work, a magnetic molecularly imprinted chitosan membrane (MMICM) was synthesized for the extraction of chlorobenzene compounds in environmental water using the membrane separation method. The optimal extraction amount for chlorobenzene (9.64 mg·L-1) was found to be a 1:2 solid to liquid ratio, with a 20 min extraction time and 35 °C extraction temperature. This method proved to be successfully applied for the separation and trace quantification of chlorobenzene compounds in environmental water, with the limit of detection (LOD) (0.0016-0.057 ng·L-1), limit of quantification (LOQ) (0.0026-0.098 ng·L-1), and the recoveries ranging (89.02-106.97%).

15.
J Hazard Mater ; 440: 129699, 2022 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-35963094

RESUMO

This study explored chlorinated paraffin (CP)-degrading bacteria from the marine environment. Aequorivita, Denitromonas, Parvibaculum, Pseudomonas and Ignavibacterium were selected as the dominant genera after enrichment with chlorinated paraffin 52 (CP52) as the sole carbon source. Eight strains were identified as CP degraders, including Pseudomonas sp. NG6 and NF2, Erythrobacter sp. NG3, Castellaniella sp. NF6, Kordiimonas sp. NE3, Zunongwangia sp. NF12, Zunongwangia sp. NH1 and Chryseoglobus sp. NF13, and their degradation efficiencies ranged from 6.4% to 19.0%. In addition to Pseudomonas, the other six genera of bacteria were first reported to have the degradation ability of CPs. Bacterial categories, carbon-chain lengths and chlorination degrees were three crucial factors affecting the degradation efficiencies of CPs, with their influential ability of chlorinated degrees > bacterial categories > carbon-chain lengths. CP degradation can be performed by producing chlorinated alcohols, chlorinated olefins, dechlorinated alcohols and lower chlorinated CPs. This study will provide valuable information on CP biotransformation and targeted bacterial resources for studying the transformation processes of specific CPs in marine environments.


Assuntos
Hidrocarbonetos Clorados , Parafina , Álcoois , Alcenos , Bactérias , Carbono , China , Monitoramento Ambiental , Hidrocarbonetos Clorados/análise , Parafina/análise
16.
Chemosphere ; 304: 135231, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35688193

RESUMO

The wide application of fungicides is becoming one of the main causes of water pollution. Activated carbon (AC) is a frequently-used adsorbent in water treatment. In this work, aiming to obtain a better understanding of fungicides on AC, carbendazim was selected as a model fungicide in water. The effects of AC dosage, adsorption temperature, adsorption time and pH value of solution on carbendazim adsorption by AC were investigated. When the initial concentration of carbendazim was 500 mg L-1 and the volume of wastewater was 25 mL, the optimum dosage of AC and reaction time was determined to be 0.3 g and 150 min, respectively. The pH ranging from 3.0 to 10.0 exhibited little effect on the adsorption capability of AC. The higher the adsorption temperature was, the better adsorption capacity was. Adsorption capacity could reach 32.31 mg g-1 under the optimal adsorption conditions. The kinetics study reveals that the adsorption of carbendazim occurred on the surface of adsorbent during initial stage. The adsorption data was well fitted by Langmuir adsorption isotherm, indicating that the adsorption process was monolayer adsorption. The thermodynamic experiments confirmed that the adsorption of carbendazim was an endothermic process with the coexistence of physical and chemical adsorption. Because the main components of AC used in this research work is amorphous carbon with low impurity and its surface has not been modified with additional functional groups, the conclusion of the study was easy to be replicated by repeated experiments. Therefore, the findings of this study could guide the adsorption of carbendazim onto the other kinds of AC with high specific surface area, and provide useful information for application of commercial AC in treatment of fungicides wastewater.


Assuntos
Fungicidas Industriais , Poluentes Químicos da Água , Adsorção , Benzimidazóis , Carbamatos , Carvão Vegetal , Concentração de Íons de Hidrogênio , Cinética , Termodinâmica , Águas Residuárias , Poluentes Químicos da Água/análise
17.
Artigo em Inglês | MEDLINE | ID: mdl-35615689

RESUMO

Aucubin, a natural compound isolated from herbal medicine, has been reported to possess multiple beneficial properties. In this study, we aimed to verify the anticancer effect of aucubin on breast cancer and investigate the effect of cancer on the intestinal flora and whether aucubin has a therapeutic effect on intestinal problems caused by cancer. We established the breast cancer model with mouse 4T1 cell line and BALB/c mice. Aucubin was given once a day by gavage for 14 days. The results showed that aucubin suppress the growth of tumor in vivo by inducing tumor cell apoptosis. The tumor suppression rate of aucubin could reach 51.31 ± 4.07%. Organ histopathology was evaluated by tissue staining, which demonstrated that aucubin could alleviate the organ inflammatory damage caused by breast cancer without visible side effects. Moreover, aucubin could increase the expression of colonic tight junction protein occluding and adjust the gut microbiome to normal level according to 16S rDNA high-throughput sequencing. Herein, our results provide evidence for developing aucubin as an alternative and safe therapeutic for breast cancer treatment.

18.
Chemosphere ; 287(Pt 1): 132118, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34523461

RESUMO

Zr/CTAB/BAC was prepared by bamboo activated carbon (BAC) functionalised by zirconia chloride octahydrate (ZrOCl2·8H2O) and Cetyltrimethylammonium bromide (CTAB). The effects of temperature, time, Zr dosage and CTAB concentration on removing phosphate and nitrate (H2PO4- and NO3-) in wastewater were investigated. The structure of Zr/CTAB/BAC was characterized by SEM, BET, FTIR, XRD and TG, and the kinetics and thermodynamics of adsorption were discussed. The optimum preparation conditions were as follows: the modification temperature was 25 °C, the modification time was 4 h, the mass of the modifier Zr added was 0.40 g, and the concentration of the modifier CTAB was 0.6 mM. When the dosage of Zr/CTAB/BAC was in the range of 0.1 g-1.0 g, the removal efficiency of phosphate in simulated wastewater was between 59.32% and 99.42%, and the removal efficiency of nitrate was between 34.08% and 93.70%. Using NaOH as a regenerant, after four times adsorption and desorption experiments, the removal efficiency of phosphate and nitrate by Zr/CTAB/BAC can still reach more than 70%. The chemical adsorption was the primary cause of the adsorption, and the adsorption process was endothermic. Zr/CTAB/BAC had an obvious removal effect on phosphate and nitrate in water, which could be promoted to treat other anionic salts in sewage.


Assuntos
Carvão Vegetal , Poluentes Químicos da Água , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Nitratos , Fosfatos , Poluentes Químicos da Água/análise
19.
Environ Sci Pollut Res Int ; 29(9): 12441-12449, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34231150

RESUMO

A continuous fixed-bed column study was used to evaluate phosphate adsorption performance of U-D-Na which was functionalized by the cheap NaCl reagent after simple ultrasonic purification of diatomite. In this work, various effect factors, including flow rate, initial phosphate concentration, and the bed height, on breakthrough performance of fixed column were investigated. Experimental results demonstrated that the breakthrough time declined with the increase of inlet phosphate concentration and feed rate, whereas the increase of bed height turned out to significantly extend the breakthrough time. The dynamic adsorption process could be well fitted by the Thomas model, with a correlation coefficient R2 > 0.9000 under main operating conditions. A thrice loop of effective regeneration was achieved with 0.1 M hydrochloric acid eluent and deionized water. The maximum removal rate for phosphate was more than 95% in the column adsorption process. The results proved that U-D-Na could be used as a better alternative phosphate adsorbent for wastewater in a continuous column sorption process.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Adsorção , Terra de Diatomáceas , Fosfatos , Água , Poluentes Químicos da Água/análise
20.
J Sep Sci ; 45(4): 883-895, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34919334

RESUMO

Growing concerns related to antibiotic residues in environmental water have encouraged the development of rapid, sensitive, and accurate analytical methods. Single-drop microextraction has been recognized as an efficient approach for the isolation and preconcentration of several analytes from a complex sample matrix. Thus, single-drop microextraction techniques are cost-effective and less harmful to the environment, subscribing to green analytical chemistry principles. Herein, an overview and the current advances in single-drop microextraction for the determination of antibiotics in environmental water are presented were included. In particular, two main approaches used to perform single-drop microextraction (direct immersion-single-drop microextraction and headspace-single-drop microextraction) are reviewed. Furthermore, the impressive analytical features and future perspectives of single-drop microextraction are discussed in this review.


Assuntos
Microextração em Fase Líquida , Água , Antibacterianos , Microextração em Fase Líquida/métodos
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