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1.
J Am Chem Soc ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38842530

RESUMO

Photocatalytic C2H6-to-C2H4 conversion is very promising, yet it remains a long-lasting challenge due to the high C-H bond dissociation energy of 420 kJ mol-1. Herein, partially oxidized Pdδ+ species anchored on ZnO nanosheets are designed to weaken the C-H bond by the electron interaction between Pdδ+ species and H atoms, with efforts to achieve high-rate and selective C2H6-to-C2H4 conversion. X-ray photoelectron spectra, Bader charge calculations, and electronic localization function demonstrate the presence of partially oxidized Pdδ+ sites, while quasi-in situ X-ray photoelectron spectra disclose the Pdδ+ sites initially adopt and then donate the photoexcited electrons for C2H6 dehydrogenation. In situ electron paramagnetic resonance spectra, in situ Fourier transform infrared spectra, and trapping agent experiments verify C2H6 initially converts to CH3CH2OH via ·OH radicals, then dehydroxylates to CH3CH2· and finally to C2H4, accompanied by H2 production. Density-functional theory calculations elucidate that loading Pd site can lengthen the C-H bond of C2H6 from 1.10 to 1.12 Å, which favors the C-H bond breakage, affirmed by a lowered energy barrier of 0.04 eV. As a result, the optimized 5.87% Pd-ZnO nanosheets achieve a high C2H4 yield of 16.32 mmol g-1 with a 94.83% selectivity as well as a H2 yield of 14.49 mmol g-1 from C2H6 dehydrogenation in 4 h, outperforming all the previously reported photocatalysts under similar conditions.

2.
Nanomaterials (Basel) ; 14(9)2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38727380

RESUMO

Antibiotic abuse, particularly the excessive use of tetracycline (TC), a drug with significant environmental risk, has gravely harmed natural water bodies and even posed danger to human health. In this study, a three-dimensional self-supported MoS2/MXene nanohybrid with an expanded layer spacing was synthesized via a facile one-step hydrothermal method and used to activate peroxydisulfate (PDS) for the complete degradation of TC. The results showed that a stronger •OH signal was detected in the aqueous solution containing MoS2/MXene, demonstrating a superior PDS activation effect compared to MoS2 or Ti3C2TX MXene alone. Under the conditions of a catalyst dosage of 0.4 g/L, a PDS concentration of 0.4 mM, and pH = 5.0, the MoS2/MXene/PDS system was able to fully eliminate TC within one hour, which was probably due to the presence of several reactive oxygen species (ROS) (•OH, SO4•-, and O2•-) in the system. The high TC degradation efficiency could be maintained under the influence of various interfering ions and after five cycles, indicating that MoS2/MXene has good anti-interference and reusability performance. Furthermore, the possible degradation pathways were proposed by combining liquid chromatography-mass spectrometry (LC-MS) data and other findings, and the mechanism of the MoS2/MXene/PDS system on the degradation process of TC was elucidated by deducing the possible mechanism of ROS generation in the reaction process. All of these findings suggest that the MoS2/MXene composite catalyst has strong antibiotic removal capabilities with a wide range of application prospects.

3.
Materials (Basel) ; 17(5)2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38473590

RESUMO

Transition metals and their oxide compounds exhibit excellent chemical reactivity; however, their easy agglomeration and high cost limit their catalysis applications. In this study, an interpolation structure of a Myriophyllum verticillatum L. biochar-supported Mn/Mg composite (Mn/Mg@MV) was prepared to degrade triphenyl phosphate (TPhP) from wastewater through the activating periodate (PI) process. Interestingly, the Mn/Mg@MV composite showed strong radical self-producing capacities. The Mn/Mg@MV system degraded 93.34% TPhP (pH 5, 10 µM) within 150 min. The experimental results confirmed that the predominant role of IO3· and the auxiliary ·OH jointly contributed to the TPhP degradation. In addition, the TPhP pollutants were degraded to various intermediates and subsequent Mg mineral phase mineralization via mechanisms like interfacial processes and radical oxidation. DFT theoretical calculations further indicated that the synergy between Mn and Mg induced the charge transfer of the carbon-based surface, leading to the formation of an ·OH radical-enriched surface and enhancing the multivariate interface process of ·OH, IO3, and Mn(VII) to TPhP degradation, resulting in the further formation of Mg PO4 mineralization.

4.
Adv Mater ; 36(23): e2314209, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38331431

RESUMO

Electrochemically reconstructed Cu-based catalysts always exhibit enhanced CO2 electroreduction performance; however, it still remains ambiguous whether the reconstructed Cu vacancies have a substantial impact on CO2-to-C2+ reactivity. Herein, Cu vacancies are first constructed through electrochemical reduction of Cu-based nanowires, in which high-angle annular dark-field scanning transmission electron microscopy image manifests the formation of triple-copper-vacancy associates with different concentrations, confirmed by positron annihilation lifetime spectroscopy. In situ attenuated total reflection-surface enhanced infrared absorption spectroscopy discloses the triple-copper-vacancy associates favor *CO adsorption and fast *CO dimerization. Moreover, density-functional-theory calculations unravel the triple-copper-vacancy associates endow the nearby Cu sites with enriched and disparate local charge density, which enhances the *CO adsorption and reduces the CO-CO coupling barrier, affirmed by the decreased *CO dimerization energy barrier by 0.4 eV. As a result, the triple-copper-vacancy associates confined in Cu nanowires achieve a high Faradaic efficiency of over 80% for C2+ products in a wide current density range of 400-800 mA cm-2, outperforming most reported Cu-based electrocatalysts.

5.
Chemphyschem ; 25(5): e202300368, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38193665

RESUMO

The goal of photocatalytic CO2 reduction system is to achieve near 100 % selectivity for the desirable product with reasonably high yield and stability. Here, two-dimensional metal-organic frameworks are constructed with abundant and uniform monometallic active sites, aiming to be an emerged platform for efficient and selective CO2 reduction. As an example, water-stable Cu-based metal-organic framework nanoribbons with coordinatively unsaturated single CuII sites are first fabricated, evidenced by X-ray diffraction patterns and X-ray absorption spectroscopy. In situ Fourier-transform infrared spectra and Gibbs free energy calculations unravel the formation of the key intermediate COOH* and CO* is an exothermic and spontaneous process, whereas the competitive hydrogen evolution reaction is endothermic and non-spontaneous, which accounts for the selective CO2 reduction. As a result, in an aqueous solution containing 1 mol L-1 KHCO3 and without any sacrifice reagent, the water-stable Cu-based metal-organic framework nanoribbons exhibited an average CO yield of 82 µmol g-1 h-1 with the selectivity up to 97 % during 72 h cycling test, which is comparable to other reported photocatalysts under similar conditions.

6.
Nanomaterials (Basel) ; 13(12)2023 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-37368267

RESUMO

Microwave-absorbing materials have attracted extensive attention due to the development of electronic countermeasures. In this study, novel nanocomposites with core-shell structures based on the core of Fe-Co nanocrystals and the shell of furan methylamine (FMA)-modified anthracite coal (Coal-F) were designed and fabricated. The Diels-Alder (D-A) reaction of Coal-F with FMA creates a large amount of aromatic lamellar structure. After the high-temperature treatment, the modified anthracite with a high degree of graphitization showed an excellent dielectric loss, and the addition of Fe and Co effectively enhanced the magnetic loss of the obtained nanocomposites. In addition, the obtained micro-morphologies proved the core-shell structure, which plays a significant role in strengthening the interface polarization. As a result, the combined effect of the multiple loss mechanism promoted a remarkable improvement in the absorption of incident electromagnetic waves. The carbonization temperatures were specifically studied through a setting control experiment, and 1200 °C was proved to be the optimum parameter to obtain the best dielectric loss and magnetic loss of the sample. The detecting results show that the 10 wt.% CFC-1200/paraffin wax sample with a thickness of 5 mm achieves a minimum reflection loss of -41.6 dB at a frequency of 6.25 GHz, indicating an excellent microwave absorption performance.

7.
Adv Mater ; 35(31): e2302538, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37120752

RESUMO

The slow charge dynamics and large activation energy of CO2 severely hinder the efficiency of CO2 photoreduction. Defect engineering is a well-established strategy, while the function of common zero-dimensional defects is always restricted to promoting surface adsorption. In this work, a gradient layer of tungsten vacancies with a thickness of 3-4 nm is created across Bi2 WO6 nanosheets. This gradient layer enables the formation of an inner-to-outer tandem homojunction with an internal electric field, which provides a strong driving force for the migration of photoelectrons from the bulk to the surface. Meanwhile, W vacancies change the coordination environment around O and W atoms, leading to an alteration in the basic sites and the mode of CO2 adsorption from weak/strong adsorption to moderate adsorption, which ultimately decreases the formation barrier of the key intermediate *COOH and facilitates the conversion thermodynamics for CO2 . Without any cocatalyst and sacrificial reagent, W-vacant Bi2 WO6 shows an outstanding photocatalytic CO2 reduction performance with a CO production rate of 30.62 µmol g-1  h-1 , being one of the best catalysts in similar reaction systems. This study reveals that gradient vacancies as a new type of defect will show huge potential in regulating charge dynamics and catalytic reaction thermodynamics.

8.
Angew Chem Int Ed Engl ; 62(1): e202215247, 2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36347791

RESUMO

Herein, we first design a model of reversible redox-switching metal-organic framework single-unit-cell sheets, where the abundant metal single sites benefit for highly selective CO2 reduction, while the reversible redox-switching metal sites can effectively activate CO2 molecules. Taking the synthetic Cu-MOF single-unit-cell sheets as an example, synchrotron-radiation quasi in situ X-ray photoelectron spectra unravel the reversible switching CuII /CuI single sites initially accept photoexcited electrons and then donate them to CO2 molecules, which favors the rate-liming activation into CO2 δ- , verified by in situ FTIR spectra and Gibbs free energy calculations. As an outcome, Cu-MOF single-unit-cell sheets achieve near 100 % selectivity for CO2 photoreduction to CO with a high rate of 860 µmol g-1 h-1 without any sacrifice reagent or photosensitizer, where both the activity and selectivity outperform previously reported photocatalysts evaluated under similar conditions.

9.
Artigo em Inglês | MEDLINE | ID: mdl-36185085

RESUMO

Objectives: Conventional approaches for patients with nonerosive gastroesophageal reflux disease (NERD) were not satisfactory. This study aimed to evaluate the effectiveness and mechanisms of Chinese herbal medicine Hewei Jiangni Decoction (HWJND) as a novel and promising regimen for NERD. Methods: A total of 128 patients with NERD were randomly assigned to the Treatment group and Control group. The patients from the Treatment group were administered HWJND (81 g) plus dummy omeprazole (20 mg) daily for 8 weeks, and the others were given dummy HWJND granules (81 g) plus omeprazole (20 mg). The clinical efficacy was assessed using the gastroesophageal reflux disease questionnaire (GERD-Q) scale, patient reported outcomes (PRO) scale, and short form health survey 36 (SF-36) scale at week 4. Moreover, its pharmacological and molecular mechanisms were elucidated based on network pharmacology and molecular docking. Results: Due to case shedding and other reasons, 109 patients, including 56 in the Treatment group and 53 in the Control group completed this study. Our results showed that HWJND significantly improved heartburn, regurgitation, epigastric pain, nausea, and sleep disturbance, which led to a significant reduction of GERD-Q scores in NERD patients. In addition, PRO scores of NERD patients with HWJND administration were improved, and sufficient relief of physical role, body pain, general health, social function, and mental health on the SF-36 scale was also observed in patients after HWJND treatment. We further showed that the curative effect of HWJND was close to that of omeprazole, except for the better improvement of general health and social function. What's more, the main active ingredients of HWJND included quercetin, beta-sitosterol, naringenin, baicalein, and kaempferol were retrieved, and the protective effects of HWJND against NERD may be closely related to targets such as TNF, IL6, IL1B, MMP9, CXCL8, and EGFR, which were mainly enriched in IL-17 signaling pathway and TNF signaling pathway. Conclusion: Our findings demonstrate that HWJND is noninferior to oral omeprazole for the treatment of patients with NERD, plays a therapeutic role through multiple targets and diverse pathways, and holds promise for complementary and alternative therapy for the treatment of NERD. This trial is registered with http://www.chictr.org.cn, Chinese Clinical Trials Registry [ChiCTR2200055960].

10.
Angew Chem Int Ed Engl ; 61(51): e202214490, 2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36307955

RESUMO

The chemical conversion of CO2 to long-chain chemicals is considered as a highly attractive method to produce value-added organics, while the underlying reaction mechanism remains unclear. By constructing surface vacancy-cluster-mediated solid frustrated Lewis pairs (FLPs), the 100 % atom-economical, efficient chemical conversion of CO2 to dimethyl carbonate (DMC) was realized. By taking CeO2 as a model system, we illustrate that FLP sites can efficiently accelerate the coupling and conversion of key intermediates. As demonstrated, CeO2 with rich FLP sites shows improved reaction activity and achieves a high yield of DMC up to 15.3 mmol g-1 . In addition, by means of synchrotron radiation in situ diffuse reflectance infrared Fourier-transform spectroscopy, combined with density functional theory calculations, the reaction mechanism on the FLP site was investigated systematically and in-depth, providing pioneering insights into the underlying pathway for CO2 chemical conversion to long-chain chemicals.

11.
Artigo em Inglês | MEDLINE | ID: mdl-36293698

RESUMO

Nowadays, with the rapid development of industry and agriculture, heavy metal pollution is becoming more and more serious, mainly deriving from natural and man-made sources [...].


Assuntos
Metais Pesados , Poluentes do Solo , Humanos , Biodegradação Ambiental , Poluentes do Solo/análise , Metais Pesados/análise , Agricultura , Solo
12.
Oxid Med Cell Longev ; 2022: 9144644, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35693700

RESUMO

Ovarian damage induced by platinum-based chemotherapy seriously affects young women with cancer, manifesting as infertility, early menopause, and premature ovarian insufficiency. However, effective prevention strategies for such damage are lacking. Senescent cells may be induced by chemotherapeutic agents. We hypothesized that cisplatin can lead to senescence in ovarian cells during the therapeutic process, and senolytic drugs can protect animals against cisplatin-induced ovarian injury. Here, we demonstrated the existence of senescent cells in cisplatin-treated ovaries, identified the senescence-associated secretory phenotype, and observed significant improvement of ovarian function by treatment with metformin or dasatinib and quercetin (DQ) independently or in combination. These senotherapies improved both oocyte quality and fertility, increased the ovarian reserve, and enhanced hormone secretion in cisplatin-exposed mice. Additionally, attenuated fibrosis, reorganized subcellular structure, and mitigated DNA damage were observed in the ovaries of senotherapeutic mice. Moreover, RNA sequencing analysis revealed upregulation of the proliferation-related genes Ki, Prrx2, Sfrp4, and Megfl0; and the antioxidative gene H2-Q10 after metformin plus DQ treatment. Gene ontology analysis further revealed that combining senotherapies enhanced ovarian cell differentiation, development, and communication. In this study, we demonstrated that metformin plus DQ recovered ovarian function to a greater extent compared to metformin or DQ independently, with more follicular reserve, increased pups per litter, and reduced DNA damage. Collectively, our work indicates that senotherapies might prevent cisplatin-induced ovarian injury by removing senescent cells and reducing DNA damage, which represent a promising therapeutic avenue to prevent chemotherapy-induced ovarian damage.


Assuntos
Cisplatino , Metformina , Animais , Apoptose , Senescência Celular , Dano ao DNA , Feminino , Proteínas de Homeodomínio/farmacologia , Humanos , Metformina/farmacologia , Camundongos
13.
J Am Chem Soc ; 144(23): 10446-10454, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35640069

RESUMO

CO2 electroreduction to high-energy-density C2+ products is highly attractive, whereas the C2+ selectivity under industrial current densities is still unsatisfying. Here, an anti-swelling anion exchange ionomer (AEI) was first proposed to optimize the local environment for promoting industrial-current-density CO2-to-C2+ electroreduction. Taking the anti-swelling AEI-modified oxide-derived Cu nanosheets as an example, in situ Raman spectroscopy and contact angle measurements revealed that the OH--accumulated -N(CH3)3+ groups and anti-swelling backbone of AEI could synergistically regulate the local pH level and water content. In situ Fourier-transform infrared spectroscopy and theoretical calculations demonstrated that the higher local pH value could lower the energy barrier for the rate-limiting COCO* hydrogenated to COCOH* from 0.08 to 0.04 eV, thereby boosting the generation of C2+ products. Owing to the anti-swelling backbone, the optimized water content of 3.5% could suppress the competing H2 evolution and hence facilitate the proton-electron transfer step for C2+ production. As a result, the anti-swelling AEI-modified oxide-derived Cu nanosheets achieved a C2+ Faradaic efficiency of 85.1% at a current density up to 800 mA cm-2 with a half-cell power conversion efficiency exceeding 50%, outperforming most reported powder catalysts.

14.
Bull Environ Contam Toxicol ; 109(1): 142-148, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35305129

RESUMO

Bauxite residue is generated from alumina production in the alumina refining industry by the Bayer process, which requires a large amount of land resource and causes serious environmental problems. In this paper, a novel recycling strategy is proposed to rehabilitate the land and produce the polyaluminium ferric sulfate (PAFS) and siliceous gypsum byproducts from the bauxite residue. The batch experiments reveal that the maximum Cr(VI) removal efficiency of as-prepared PAFS can reach 95.80% with an initial concentration of 10.41 mg/L. In addition, the non-toxic siliceous gypsum should be an ideal raw material for cement plants. Various characterizations (e.g., SEM, FTIR, and XRD) are employed to reveal the mechanism of synthesis PAFS and their Cr(VI) removal performance. Consequently, this paper provides a deep insight into the utilization of bauxite residue as a resource and gives a new strategy for preparing PAFS and gypsum from bauxite residue.


Assuntos
Óxido de Alumínio , Águas Residuárias , Sulfato de Cálcio , Cromo , Compostos Férricos
15.
Ecotoxicol Environ Saf ; 220: 112370, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34058673

RESUMO

A 6 weeks pot culture experiment was carried out to investigate the stabilization effects of a modified biochar (BCM) on metals in contaminated soil and the uptake of these metals by wheat seedlings. The results showed that the application of BCM significantly increased the soil fertility, the biomass of wheat seedling roots increased by more than 50%, and soil dehydrogenase (DHA) and catalase (CAT) activities increased by 369.23% and 12.61%, respectively. In addition, with the application of BCM, the diethylenetriaminepentaacetic acid extractable (DTPA-extractable) Cd, Pb, Cu and Zn in soil were reduced from 2.34 to 0.38 mg/kg, from 49.27 to 25.65 mg/kg, from 3.55 mg/kg to below the detection limit and from 4.05 to 3.55 mg/kg, respectively. Correspondingly, the uptake of these metals in wheat roots and shoots decreased by 62.43% and 79.83% for Cd, 73.21% and 66.32% for Pb, 57.98% and 68.92% for Cu, and 40.42% and 43.66% for Zn. Furthermore, BCM application decreased the abundance and alpha diversity of soil bacteria and changed the soil bacterial community structure dramatically. Overall, BCM has great potential for the remediation of metal-contaminated soils, but its long-term impact on soil metals and biota need further research.


Assuntos
Bactérias/efeitos dos fármacos , Carvão Vegetal/farmacologia , Metais Pesados/metabolismo , Plântula/metabolismo , Poluentes do Solo/metabolismo , Solo/química , Triticum/efeitos dos fármacos , Disponibilidade Biológica , Biomassa , Cádmio/metabolismo , Poluição Ambiental , Raízes de Plantas/metabolismo , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Microbiologia do Solo , Triticum/crescimento & desenvolvimento , Triticum/metabolismo
16.
Angew Chem Int Ed Engl ; 60(25): 13840-13846, 2021 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-33786954

RESUMO

Herein, we first design a fast low-pressure ultraviolet light irradiation strategy for easily regenerating the nearly equivalent surface vacancies. Taking the defective Bi2 O2 CO3 nanosheets as an example, nearly equal amount of oxygen vacancies can be regenerated under UV light irradiation. Synchrotron-radiation quasi in situ X-ray photoelectron spectra disclose the Bi sites in the O-defective Bi2 O2 CO3 nanosheets can act as the highly active sites, which not only help to activate CO2 molecules, but also contribute to stabilizing the rate-limiting COOH* intermediate. Also, in situ Fourier transform infrared spectroscopy and in situ mass spectrometry unravel the UV light irradiation contributes to accelerating CO desorption process. As a result, the O-defective Bi2 O2 CO3 nanosheets achieve a stability up to 2640 h over 110 cycling tests and a high evolution rate of 275 µmol g-1 h-1 for visible-light-driven CO2 reduction to CO.

17.
Ecotoxicol Environ Saf ; 207: 111294, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32931971

RESUMO

Heavy metal contamination in soil has attracted great attention worldwide. In situ stabilization has been considered an effective way to remediate soils contaminated by heavy metals. In the present research, a multiple-modified biochar (BCM) was prepared to stabilize Cd and Cu contamination in two different soils: a farmland soil (JYS) and a vegetable soil (ZZS). The results showed that BCM was a porous-like flake material and that modification increased its specific surface area and surface functional groups. The incubation experiment indicated that BCM decreased diethylenetriaminepentaacetic (DTPA)-extractable Cd and Cu by 92.02% and 100.00% for JYS and 90.27% and 100.00% for ZZS, respectively. The toxicity characteristic leaching procedure (TCLP)-extractable Cd and Cu decreased 66.46% and 100.00% for JYS and 46.33% and 100.00% for ZZS, respectively. BCM also reduced the mobility of Cd and Cu in soil and transformed them to more stable fractions. In addition, the application of BCM significantly increased the soil dehydrogenase, organic matter content and available K (p < 0.05). These results indicate that BCM has great potential in the remediation of Cd- and Cu-contaminated soil.


Assuntos
Cádmio/análise , Carvão Vegetal/química , Cobre/análise , Recuperação e Remediação Ambiental/métodos , Poluentes do Solo/análise , Solo/química , Adsorção , China , Propriedades de Superfície
18.
Environ Technol ; 42(17): 2749-2756, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31961776

RESUMO

Di-n-octyl phthalate (DOP), a plasticizer used in many different industrial products, is a frequently observed pollutant in the environment. Biodegradation by microorganisms is considered to be a realistic choice for the remediation of DOP contamination. In the present research, the halotolerant bacterial consortium (LF) enriched in our previous research was used to degrade DOP. It was found that the optimal conditions for LF to degrade DOP was temperature 30oC, pH 6.0, inoculum size >5%, and salt content <3%. LF could degrade a high concentration of DOP (2000 mg/L) with the removal efficiency of 96.33%. Substrate inhibition analyses indicated that the inhibition constant, maximum specific degradation rate and half-saturation constant were 2544.6 mg/L, 0.7 d-1 and 59.1 mg/L, respectively. Based on the analysis of the gas chromatography-mass spectrometry (GC-MS), the biodegradation pathway for DOP by LF was proposed. Furthermore, LF could degrade DOP in soil (100 mg/kg) with the highest removal efficiency of 89.3%. This study is the first report on DOP biodegradation by bacterial consortium. These results suggest that LF can be used to remediate DOP-contaminated environment.


Assuntos
Ácidos Ftálicos , Solo , Biodegradação Ambiental , Temperatura
19.
Sci Total Environ ; 756: 143871, 2021 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-33293086

RESUMO

Layer-structured graphene oxide excellent carrier for modifications; however, its poor recoverability and stability preclude its application in wastewater treatment fields. Herein, three-dimensional magnetic fungal hyphal/graphene oxide nanofibers (MFHGs) were assembled by a reductive self-assembly (RSA) strategy for the efficient capture of Co(II) and Ni(II) from high-salinity aqueous solution. The RSA strategy is inexpensive, eco-friendly and easy to scale up. The obtained MFHGs enhanced the dispersity and stability of graphene oxide and exhibited excellent magnetization and large coercivity, leading to satisfactory solid-liquid separation performance and denser sediment. The results of batch removal experiments showed that the maximum removal capacity of MFHGs for Ni(II) and Co(II) was 97.44 and 104.34 mg/g, respectively, in 2 g/L Na2SO4 aqueous solution with a pH of 6.0 at 323 K, and the effects of initial pH and ionic strength on Co(II) and Ni(II) removal were explored. Yield residue analysis indicated that the high porosity and oxygen-containing functional groups of MFHGs remarkably improved their Co(II)- and Ni(II)-removal capacities. According to the analysis, hydroxyl groups and amine groups participated in the chemical reaction of Co(II) and Ni(II) removal, and cation-exchange chemical adsorption was dominant during the Co(II)- and Ni(II)-removal process. Based on the attributes of MFHGs, a continuous-flow recycle reactor (CFRR) was proposed for emergency aqueous solution treatment and exhibited satisfactory removal efficiency and regeneration performance. The combination of MFHGs and the proposed CFRR is a promising water treatment strategy for rapid treatment applications.


Assuntos
Nanofibras , Poluentes Químicos da Água , Adsorção , Grafite , Fenômenos Magnéticos , Solução Salina , Salinidade , Poluentes Químicos da Água/análise
20.
Front Genet ; 11: 590660, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33304387

RESUMO

Ovarian aging leads to reproductive and endocrine dysfunction, causing the disorder of multiple organs in the body and even declined quality of offspring's health. However, few studies have investigated the changes in gene expression profile in the ovarian aging process. Here, we applied integrated bioinformatics to screen, identify, and validate the critical pathogenic genes involved in ovarian aging and uncover potential molecular mechanisms. The expression profiles of GSE84078 were downloaded from the Gene Expression Omnibus (GEO) database, which included the data from ovarian samples of 10 normal C57BL/6 mice, including old (21-22 months old, ovarian failure period) and young (5-6 months old, reproductive bloom period) ovaries. First, we filtered 931 differentially expressed genes (DEGs), including 876 upregulated and 55 downregulated genes through comparison between ovarian expression data from old and young mice. Functional enrichment analysis showed that biological functions of DEGs were primarily immune response regulation, cell-cell adhesion, and phagosome pathway. The most closely related genes among DEGs (Tyrobp, Rac2, Cd14, Zap70, Lcp2, Itgb2, H2-Ab1, and Fcer1g) were identified by constructing a protein-protein interaction (PPI) network and consequently verified using mRNA and protein quantitative detection. Finally, the immune cell infiltration in the ovarian aging process was also evaluated by applying CIBERSORT, and a correlation analysis between hub genes and immune cell type was also performed. The results suggested that plasma cells and naïve CD4+ T cells may participate in ovarian aging. The hub genes were positively correlated with memory B cells, plasma cells, M1 macrophages, Th17 cells, and immature dendritic cells. In conclusion, this study indicates that screening for DEGs and pathways in ovarian aging using bioinformatic analysis could provide potential clues for researchers to unveil the molecular mechanism underlying ovarian aging. These results could be of clinical significance and provide effective molecular targets for the treatment of ovarian aging.

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