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1.
Heliyon ; 10(7): e27921, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38571621

RESUMO

Culter alburnus (topmouth culter)is an economically valuable freshwater fish. However, its insufficient tolerance to dissolved oxygen (DO) and ammonia nitrogen (AN) hinders its industrialisation. 360 experimental fish (4.87 ± 1.10 g) were placed in breathing chambers (oxygen level was 0.70-6.50 mg/L) or water tanks (control AN, 0 mg/L; low AN, 8 mg/L; high AN, 16 mg/L). This study analysed the effects of DO and AN on C. alburnus at physiological, biochemical, and molecular levels. (1) Physiology level: the floating point, coma critical point, and coma point at 20 °C group were significantly higher than those at 30 °C. The oxygen consumption rate of C. alburnus at 20 °C, 25 °C, and 30 °C was (256.65 ± 25.87), (470.47 ± 83.84), and (520.87 ± 55.40) mg/kg.h. The LC50 of AN after 96 h was 24.13 mg/L, and the safe concentration was 2.41 mg/L. The survival rate in the high AN group was significantly lower than that in the other two groups. (2) Biochemistry level: The change curves of antioxidant enzyme activity in the liver tissue under hypoxic stress reached a maximum at 12 h and then decreased. In addition, the increase and decrease in enzyme activity (except malondialdehyde) in the high AN group was lower than that in the low AN group. (3) Molecular level: the angiotensin-converting enzyme and carboxypeptidase genes were the major differentially expressed genes (DEGs) in hypoxic stress, and the DEGs were mainly enriched in the ABC transporter signal transduction pathway. In addition, the serum/glucocorticoid-regulated kinase, stearoyl-CoA desaturase, and 3-hydroxy-3-methylglutaryl-coenzyme A reductase genes were among the major DEGs under high AN stress. The DEGs were mainly enriched in steroid biosynthesis or glycine, serine, and threonine metabolism transporter signal transduction pathways. In summary, it is necessary to focus on the DO and AN during C. alburnus breeding.

2.
Foods ; 13(8)2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38672877

RESUMO

There is an urgent need to develop efficient and environmentally friendly decontaminants for poultry products. In this study, we aimed to evaluate the practical application of peroxyacetic acid (PAA) as a replacement for sodium hypochlorite (SH) to sterilize fresh chicken carcasses, using microbial, color, and electronic-nose analyses. We evaluated the decontamination effects of different concentrations of PAA and SH on chicken carcasses. The bactericidal effects of PAA at pH 3, 7, and 9, and SH at pH 10, at concentrations ranging from 100 to 500 ppm on coliform bacteria, total bacteria, and Salmonella spp. were evaluated. PAA induced a similar bactericidal effect at lower concentrations than SH. Therefore, at the same concentration and treatment time, PAA showed better bactericidal effects than SH. Although treatment with PAA (pH 3) and SH (pH 10) resulted in considerable discoloration, the degree of discoloration decreased when the pH of PAA was increased to 7 and 9. Therefore, by increasing the pH of PAA, the discoloration effect on chicken carcasses can be reduced without altering the microbial-reduction effect. Electronic-nose analysis showed that the flavor of the chicken was almost unaffected by volatile components at a treatment time < 30 min. Therefore, this study experimentally identified the optimal PAA concentration for the decontamination of chicken carcasses. The study findings provide a theoretical basis for the replacement of traditional bactericides, such as SH, with PAA for the production of poultry products.

3.
Sci Adv ; 10(13): eadl4842, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38552028

RESUMO

The high-capacity advantage of lithium metal anode was compromised by common use of copper as the collector. Furthermore, lithium pulverization associated with "dead" Li accumulation and electrode cracking deteriorates the long-term cyclability of lithium metal batteries, especially under realistic test conditions. Here, we report an ultralight, integrated anode of polyimide-Ag/Li with dual anti-pulverization functionality. The silver layer was initially chemically bonded to the polyimide surface and then spontaneously diffused in Li solid solution and self-evolved into a fully lithiophilic Li-Ag phase, mitigating dendrites growth or dead Li. Further, the strong van der Waals interaction between the bottommost Li-Ag and polyimide affords electrode structural integrity and electrical continuity, thus circumventing electrode pulverization. Compared to the cutting-edge anode-free cells, the batteries pairing LiNi0.8Mn0.1Co0.1O2 with polyimide-Ag/Li afford a nearly 10% increase in specific energy, with safer characteristics and better cycling stability under realistic conditions of 1× excess Li and high areal-loading cathode (4 milliampere hour per square centimeter).

4.
Small Methods ; 8(1): e2300710, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37997223

RESUMO

An atmospheric-pressure plasma system is developed and is used to treat carbon nanotube assemblies, producing a hybrid carbon-zinc structure. This system is integrated into a floating-catalyst chemical vapor deposition furnace used for the synthesis of macroscopic assemblies of carbon nanotubes to allow for the in-line, continuous, and single-step production of nano-composite materials. Material is deposited from a sacrificial zinc wire in the form of nanoparticles and can coat the surface of the individual carbon nanotubes as they form. Additionally, it is found that the deposited materials penetrate further into the carbon nanotube matrix than a comparable post-synthesis deposition, improving the uniformity of the material through the thickness. Thus, a single-step metal-based coating and carbon nanotube synthesis process which can form the basis of production scale manufacturing of metal-carbon nanotube composite materials with an atmospheric-pressure plasma system are demonstrated.

5.
Clin Transl Med ; 13(9): e1410, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37712124

RESUMO

BACKGROUND: Predictive biomarkers for oesophageal squamous cell carcinoma (ESCC) immunotherapy are lacking, and immunotherapy resistance remains to be addressed. The role of long noncoding RNA (lncRNA) in ESCC immune escape and immunotherapy resistance remains to be elucidated. METHODS: The tumour-associated macrophage-upregulated lncRNAs and the exosomal lncRNAs highly expressed in ESCC immunotherapy nonresponders were identified by lncRNA sequencing and polymerase chain reaction assays. CRISPR-Cas9 was used to explore the functional roles of the lncRNA. RNA pull-down, MS2-tagged RNA affinity purification (MS2-TRAP) and RNA-binding protein immunoprecipitation (RIP) were performed to identify lncRNA-associated proteins and related mechanisms. In vivo, the humanized PBMC (hu-PBMC) mouse model was established to assess the therapeutic responses of specific lncRNA inhibitors and their combination with programmed cell death protein 1 (PD-1) monoclonal antibody (mAb). Single-cell sequencing, flow cytometry, and multiplex fluorescent immunohistochemistry were used to analyze immune cells infiltrating the tumour microenvironment. RESULTS: We identified a lncRNA that is involved in tumour immune evasion and immunotherapy resistance. High LINC02096 (RIME) expression in plasma exosomes correlates with a reduced response to PD-1 mAb treatment and poor prognosis. Mechanistically, RIME binds to mixed lineage leukaemia protein-1 (MLL1) and prevents ankyrin repeat and SOCS box containing 2 (ASB2)-mediated MLL1 ubiquitination, improving the stability of MLL1. RIME-MLL1 increases H3K4me3 levels in the promoter regions of programmed death-ligand 1 (PD-L1) and indoleamine 2,3-dioxygenase 1 (IDO-1), constitutively increasing the expression of PD-L1/IDO-1 in tumour cells and inhibiting CD8+ T cells infiltration and activation. RIME depletion in huPBMC-NOG mice significantly represses tumour development and improves the effectiveness of PD-1 mAb treatment by activating T-cell-mediated antitumour immunity. CONCLUSIONS: This study reveals that the RIME-MLL1-H3K4me3 axis plays a critical role in tumour immunosuppression. Moreover, RIME appears to be a potential prognostic biomarker for immunotherapy and developing drugs that target RIME may be a new therapeutic strategy that overcomes immunotherapy resistance and benefits patients with ESCC.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , RNA Longo não Codificante , Animais , Camundongos , Anticorpos Monoclonais , Antígeno B7-H1/genética , Linfócitos T CD8-Positivos , Neoplasias Esofágicas/genética , Carcinoma de Células Escamosas do Esôfago/genética , Leucócitos Mononucleares , Proteína de Leucina Linfoide-Mieloide , Receptor de Morte Celular Programada 1 , RNA Longo não Codificante/genética , Microambiente Tumoral/genética
6.
Small ; : e2305383, 2023 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-37661349

RESUMO

2D transition metal carbides and nitrides (MXenes) are actively pursued as pseudocapacitive materials for supercapacitors owing to their advantages in electronic conductivity and surface reactivity. Increasing the fraction of ─O terminal groups in Ti3 C2 Tx is a promising approach to improve the pseudocapacitive charge storage in H2 SO4 electrolytes, but it suffers from a lack of effective functionalization methods and stability of the groups in practical operation. Here a low-temperature and environment-friendly approach via the interaction of nonequilibrium plasmas with Ti3 C2 Tx dispersion is demonstrated to generate abundant and stable surface-terminating O groups. The impact of the discharge environment (Ar, O2 , and H2 ) on the structural characteristics and electrochemical performance of Ti3 C2 Tx nanosheets is studied. The Ti3 C2 Tx modified in Ar and H2 maintains their original morphology but a significantly lower F content. Consequently, an extraordinarily high content (78.5%) of surface-terminating O groups is revealed by the high-resolution X-ray photoelectron spectroscopy spectra for the Ti3 C2 Tx samples modified in H2 plasma-treated solutions. Additionally, the Ti3 C2 Tx treated using H2 plasmas exhibits the best capacitive performance of 418.3 F g-1 at 2 mV s-1 , which can maintain 95.88% capacity after 10 000 cycles. These results contribute to the development of advanced nanostructured pseudocapacitive electrode materials for renewable energy storage applications.

7.
RSC Adv ; 13(23): 15762-15771, 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37235105

RESUMO

Supercapacitors with high energy and power densities have become highly desirable in practical applications. Ionic liquids (ILs) are considered as promising electrolytes of supercapacitors owing to their excellent electrochemical stability window (approx. 4-6 V) and good thermal stability. However, the high viscosity (up to 102 mPa s) and low electric conductivity (<10 mS cm-1) at room-temperature extremely reduce the ion diffusion dynamics in the energy storage process, resulting in the unsatisfactory power density and rate performance of supercapacitors. Herein we propose a novel binary ionic liquids (BILs) hybrid electrolyte composed of two kinds of ILs in an organic solvent. Along with the organic solvent with high dielectric constant and low viscosity, the addition of binary cations effectively improves the electric conductivity and reduces the viscosity of IL electrolytes. By mixing trimethyl propylammonium bis(trifluoromethanesulfonyl)imide ([TMPA][TFSI]) and N-butyl-N-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide ([Pyr14][TFSI]) with an equal mole ratio in acetonitrile (1 M), the as-prepared BILs electrolyte shows superior electric conductivity (44.3 mS cm-1), low viscosity (0.692 mPa s), and a wide electrochemical stability window (4.82 V). The supercapacitors assembled with activated carbon electrodes (commercial mass loading) and this BILs electrolyte achieve a high working voltage of 3.1 V, leading to a maximum energy density of 28.3 W h kg-1 at 803.35 W kg-1 and a maximum power density of 32.16 kW kg-1 at 21.17 W h kg-1, which are obviously superior to those of commercial supercapacitors based on organic electrolytes (2.7 V).

8.
Molecules ; 28(6)2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-36985661

RESUMO

Mitochondria have a crucial role in regulating energy metabolism and their dysfunction has been linked to tumorigenesis. Cancer diagnosis and intervention have a great interest in the development of new agents that target biomolecules within mitochondria. However, monitoring and modulating mitochondria RNA (mtRNA), an essential component in mitochondria, in cells is challenging due to limited functional research and the absence of targeting agents. In this study, we designed and synthesized a fluorescent quinolinium derivative, QUCO-1, which actively lit up with mtRNA in both normal and cancer cells in vitro. Additionally, we evaluated the function of QUCO-1 as an mtRNA ligand and found that it effectively induced severe mitochondrial dysfunction and OXPHOS inhibition in RKO colorectal cancer cells. Treatment with QUCO-1 resulted in apoptosis, cell cycle blockage at the G2/M phase, and the effective inhibition of cell proliferation. Our findings suggest that QUCO-1 has great potential as a promising probe and therapeutic agent for mtRNA, with the potential for treating colorectal cancer.


Assuntos
Neoplasias Colorretais , Mitocôndrias , Humanos , RNA Mitocondrial/metabolismo , Mitocôndrias/metabolismo , Proliferação de Células , Apoptose , Corantes Fluorescentes/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Linhagem Celular Tumoral
9.
Phys Chem Chem Phys ; 24(35): 20674-20688, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36052687

RESUMO

Aqueous electrolytes have attracted widespread attention as they are safe, environmentally benign and cost effective, holding great promise for future low-cost and sustainable energy storage devices. Nonetheless, the narrow electrochemical stability window caused by water electrolysis, as well as the trade-off between the stability window and other properties remain the bottleneck problem for the practical applications of aqueous electrolytes. Deep insights into the correlations between the microscopic physicochemical and electrochemical mechanisms and the macroscopic properties of aqueous electrolyte are essential for the envisaged applications, yet a systematic analysis of the recent progress in this area is still lacking. In this Perspective article, the basic mechanisms and influencing factors of water electrolysis including the hydrogen evolution and oxygen evolution reactions is critically examined. We systematically review the current state-of-the-art on high-voltage aqueous electrolytes focusing on the fundamental mechanisms of ion kinetics leading to dynamic electrolyte restructuring. Recent advances on the optimization of high-voltage aqueous electrolytes are also summarized. The existing challenges are identified and perspectives for exploring and developing future high-voltage aqueous electrolytes are provided.

10.
J Med Chem ; 65(18): 12346-12366, 2022 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-36053318

RESUMO

The development of triple-negative breast cancer (TNBC) is highly associated with G-quadruplex (G4); thus, targeting G4 is a potential strategy for TNBC therapy. Because concomitant histone deacetylases (HDAC) inhibition could amplify the impact of G4-targeting compounds, we designed and synthesized two novel series of G4/HDAC dual-targeting compounds by connecting the zinc-binding pharmacophore of HDAC inhibitors to the G4-targeting isaindigotone scaffold (1). Among the new compounds, a6 with the potent HDAC inhibitory and G4 stabilizing activity could induce more DNA G4 formation than SAHA and 1 in TNBC cells. Remarkably, a6 caused more G4-related DNA damage and G4-related differentially expressed genes, consistent with its effect on disrupting the cell cycle, invasion, and glycolysis. Furthermore, a6 significantly suppresses the proliferation of various TNBC cells and the MDA-MB-231 xenograft model without evident toxicity. Our study suggests a novel strategy for TNBC therapeutics through dual-targeting HDAC and G4.


Assuntos
Antineoplásicos , Neoplasias de Mama Triplo Negativas , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , DNA/farmacologia , Inibidores de Histona Desacetilases/farmacologia , Inibidores de Histona Desacetilases/uso terapêutico , Histona Desacetilases/metabolismo , Humanos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto , Zinco/farmacologia
11.
Oxid Med Cell Longev ; 2022: 3511385, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36035203

RESUMO

Background: Central post-stroke pain (CPSP) is a common condition. Several pharmacotherapies have been applied in practice. However, the comparative effectiveness among these pharmacotherapies is unknown. Aim: The aim of this study is to study the comparative effectiveness among differential pharmacotherapies for CPSP through a network meta-analysis. Methods: We searched MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL), and Web of Science from inception to 30 March 2022, without any language restriction. Two reviewers independently screened the retrieved articles, extracted data, and evaluated the risk of bias (RoB). The outcome of interest of the study was the change in the scores of pain intensity scales. We estimated standard mean differences (SMDs) between treatments and calculated corresponding 95% CIs. Results: Thirteen randomized controlled trials (529 participants) were included after a screen of 1774 articles. Compared with placebo, pamidronate (SMD -2.43, 95% CI -3.54 to -1.31; P - score = 0.93), prednisone (SMD -2.38, 95% CI -3.09 to -1.67; P - score = 0.92), levetiracetam (SMD -2.11, 95% CI -2.97 to -1.26; P - score = 0.87), lamotrigine (SMD -1.39, 95% CI -2.21 to -0.58; P - score = 0.73), etanercept (SMD -0.92, 95% CI -1.8 to -0.03; P - score = 0.59), and pregabalin (SMD -0.46, 95% CI -0.71 to -0.22; P - score = 0.41) had significantly better treatment effect. Pamidronate, prednisone, and levetiracetam ranked as the first three most effective treatments. In subgroup analyses, prednisone, levetiracetam, lamotrigine, and pregabalin were more effective than placebo as oral pharmacotherapies, while etanercept was more effective than placebo as injectable pharmacotherapy. Conclusions: Our study confirmed that pamidronate, prednisone, and guideline-recommended anticonvulsants were effective for reducing pain intensity for CPSP. Pamidronate and prednisone showed better effect than other pharmacotherapies, which warrants further investigation.


Assuntos
Anticonvulsivantes , Dor , Etanercepte , Humanos , Lamotrigina , Levetiracetam , Metanálise em Rede , Pamidronato , Prednisona , Pregabalina
12.
Foods ; 11(7)2022 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-35407107

RESUMO

Fermentative and antioxidative characteristics of Godulbaegi kimchi (LGK), a traditional, fermented Korean food, were conducted. For the study, LGK kimchi was made of Godulbaegi kimchi with pepper powder, salted shrimp, refined salt, green onions, and so on, and fermented at 5C for 6 months. The pH was decreased, and total acidity was increased during fermentation. Furthermore, lactic acid bacteria and yeast were increased, while the total viable count was decreased. The LGK showed the highest DPPH-scavenging activity, phenol content, and nitrite-scavenging activity with methanol extract among methanol, ethanol, and water. In addition, we screened strains among LGK kimchi with high antimicrobial activity and isolated them. We tested antimicrobial activity for 20 lactic acid bacteria, and we separated and identified nine strains of lactic acid bacteria with high antimicrobial activity. Given these results, LGK is expected to be an effective food in considerable antioxidative activity with an antimicrobial effect. These results are expected to serve as basic data for the study of Godulbaegi kimchi.

13.
Nanotechnology ; 32(37)2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-34062513

RESUMO

Multilayer graphene with dense interlayer space is the most explored two-dimensional material (2DMs) in high performance gas sensor. Herein, the insertion and the diffusion behaviors of NO, NO2, NH3and H2S in the nano-confined space of graphene are investigated using density functional theory calculations. The optimum interlayer distance is found to be 6-7 Å, in which the interaction strength is enhanced by 2 -3 times compared to monolayer graphene. Based on the optimum interlayer spacing, a barrierless diffusion process is observed due to the negligible influence of adsorption sites on the adsorption energy. Besides, an enhanced adsorption of NO2is found at the edge, which leads to a small barrier (<0.15 eV) during the its inserting into graphene layers, while the barrierless process is observed for NO, NH3and H2S. As for sensing performance, an increased sensitivity is observed for NO and NO2at the edge because of the significant energy level shift and charge transfer. Meanwhile, multilayer graphene shows good selectivity towards NO2gas. Therefore, modulating the interlayer spacing of graphene layers is a promising strategy for fabricating practical low-cost gas sensors, which may facilitate future exploration of high performance gas sensor using multilayer 2DMs.

14.
Thromb Haemost ; 121(4): 422-432, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33171520

RESUMO

East Asian patients have reduced anti-ischemic benefits and increased bleeding risk during antithrombotic therapies compared with Caucasian patients. As potent P2Y12 receptor inhibitors (e.g., ticagrelor and prasugrel) and direct oral anticoagulants are commonly used in current daily practice, the unique risk-benefit trade-off in East Asians has been a topic of emerging interest. In this article, we propose updated evidence and future directions of antithrombotic treatment in East Asian patients.


Assuntos
Anticoagulantes/uso terapêutico , Doenças Cardiovasculares/tratamento farmacológico , Fibrinolíticos/uso terapêutico , Inibidores da Agregação Plaquetária/uso terapêutico , Anticoagulantes/efeitos adversos , Ásia , Povo Asiático , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/etnologia , Doenças Cardiovasculares/mortalidade , Fibrinolíticos/efeitos adversos , Hemorragia/induzido quimicamente , Humanos , Inibidores da Agregação Plaquetária/efeitos adversos , Medição de Risco , Fatores de Risco , Resultado do Tratamento
15.
Aquaculture ; 529: 735576, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32839629

RESUMO

The redclaw crayfish, Cherax quadricarinatus, is an economically valuable freshwater crayfish. However, some production obstacles, such as a low egg hatching rate and asynchronous hatching, are hindering its development in the aquaculture industry. Artificial incubation of eggs may solve these problems. This study explored the technology of artificial incubation of redclaw crayfish eggs. The following results were obtained: 1) 75% alcohol as a disinfectant for 60 s had a preferable antibacterial effect and promoted the hatching rate; 2) densities of 300 and 600 eggs/incubator resulted in significantly higher hatching and survival rates than a density of 900 eggs/incubator; 3) at a density of 600 eggs/incubator, the optimum number of net pieces for attachment of freshly hatched juveniles was 20 per incubator; 4) with a density of 600 eggs/incubator and 20 net pieces/incubator, the hatching rate was 82.05% ± 4.09%, the survival rate was 55.12% ± 7.51%, and a total of 129,200 SPF (specific pathogen-free) seedlings were cultivated. This artificial incubation system was maintained at close to an aseptic state, with an absence of white spot virus, iridovirus, Vibrio and ciliates; this was true for all water sources used and for incubation of both eggs and juvenile crayfish. In conclusion, if we implement reasonable methods of disinfection, SPF detection and pathogen isolation and utilize optimal egg densities and incubation systems, large-scale production of SPF seedlings of Cherax quadricarinatus is possible.

16.
Rev Sci Instrum ; 91(7): 076105, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32752835

RESUMO

Vertically oriented graphenes (VGs) are promising for many emerging energy and environmental applications, while their mass production still remains a critical challenge. This note reports a multi-linear antenna microwave plasma device for fabricating VGs on a large-scale. Eight coaxial linear plasma antennas are parallelly arrayed to produce large-area plasma, depositing 6 × 6 in.2 VGs on nickel foil at a high rate of 160 nm min-1. In supercapacitor applications, the potential of VGs for AC line filtering (an RC time of 0.43 ms) and decreasing the interfacial contact resistance within commercial activated carbon supercapacitors is demonstrated.

17.
ACS Appl Mater Interfaces ; 12(34): 38512-38521, 2020 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-32657570

RESUMO

Solar desalination that exploits interfacial evaporation represents a promising solution to global water scarcity. Real-world feedstocks (e.g., natural seawater and contaminated water) include oil contamination issues, raising a compelling need for desalination systems that offer anti-oil-fouling capability; however, it is still challenging to prepare oil-repellent and meanwhile water-attracting surfaces. This work demonstrates a concept of molecularly dispersing functional F and Na sites on plasma-made vertically oriented graphene nanosheets to achieve an in-air and in-water oleophobic, hydrophilic surface. The graphene architecture presents high in-air (138°) and in-water (145°) oil contact angles, with simultaneously high water affinity (0°). Such surface wettability is enabled by oleophobic, hydrophobic -CFx, and hydrophilic -COONa groups of the molecules that disperse on graphene surfaces; low-dispersion (0.439 mJ m-2) and high-polarity (95.199 mJ m-2) components of the solid surface tension; and increased surface roughness produced by graphene edges. The graphene nanostructures pump water upward by capillary action but repel oil from the surface, leading to complete in-water and in-air oil rejection and universal anti-oil-fouling capability for solar desalination. Consequently, stable solar-vapor energy efficiency of more than 85% is achieved regardless of whether the feedstock is pure or oil-contaminated water (e.g., a mixture of oil floating on water, an oil-in-water emulsion), resulting in the efficient production of clean water over several days. This outstanding performance is attributed to the universal (both in-water and in-air) oleophobic wettability, together with high light absorptance contributed by nanotraps, fast interfacial heat transfer enhanced by finlike nanostructures, and accelerated evaporation enabled by sharp graphene edges.

18.
ACS Catal ; 10(7): 4420-4432, 2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-32296596

RESUMO

In this work, we propose a hybrid and unique process combining solar irradiation and post-plasma catalysis (PPC) for the effective oxidation of toluene over a highly active and stable MnO2/GFF (bifunctional graphene fin foam) catalyst. The bifunctional GFF, serving as both the catalyst support and light absorber, is decorated with MnO2 nanofins, forming a hierarchical fin-on-fin structure. The results show that the MnO2/GFF catalyst can effectively capture and convert renewable solar energy into heat (absorption of >95%), leading to a temperature rise (55.6 °C) of the catalyst bed under solar irradiation (1 sun, light intensity 1000 W m-2). The catalyst weight (9.8 mg) used in this work was significantly lower (10-100 times lower) than that used in previous studies (usually 100-1000 mg). Introducing solar energy into the typical PPC process via solar thermal conversion significantly enhances the conversion of toluene and CO2 selectivity by 36-63%, reaching ∼93% for toluene conversion and ∼83% for CO2 selectivity at a specific input energy of ∼350 J L-1, thus remarkably reducing the energy consumption of the plasma-catalytic gas cleaning process. The energy efficiency for toluene conversion in the solar-enhanced post-plasma catalytic (SEPPC) process reaches up to 12.7 g kWh-1, ∼57% higher than that using the PPC process without solar irradiation (8.1 g kWh-1), whereas the energy consumption of the SEPPC process is reduced by 35-52%. Moreover, the MnO2/GFF catalyst exhibits an excellent self-cleaning capability induced by solar irradiation, demonstrating a superior long-term catalytic stability of 72 h at 1 sun, significantly better than that reported in previous works. The prominent synergistic effect of solar irradiation and PPC with a synergistic capacity of ∼42% can be mainly attributed to the solar-induced thermal effect on the catalyst bed, boosting ozone decomposition (an almost triple enhancement from ∼0.18 gO3 g-1 h-1 for PPC to ∼0.52 gO3 g-1 h-1 for SEPPC) to generate more oxidative species (e.g., O radicals) and enhancing the catalytic oxidation on the catalyst surfaces, as well as the self-cleaning capacity of the catalyst at elevated temperatures driven by solar irradiation. This work opens a rational route to use abundant, renewable solar power to achieve high-performance and energy-efficient removal of volatile organic compounds.

19.
J Phys Condens Matter ; 32(35): 355001, 2020 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-32320956

RESUMO

The recycling utilization of harmful nitrogen dioxide (NO2) is of great significance in pollutant control, agriculture and chemical industry. Herein, NO2 fixation using Cu decorated graphene (Cu/G) as an efficient adsorption platform is investigated through density functional theory calculations. Cu atom serves as the active site for NO2 adsorption due to the location of highest occupied molecular orbitals of Cu/G. Consequently, electrons are transferred from Cu atom to NO2, resulting in NO2 chemisorption with the large exothermicity of 3.210 eV. Electronic structure analysis further reveals the strong hybridization of NO2 with Cu is attributed to the formation of co-valence bond. Cu decorated site can adsorb up to 4 NO2 molecules, while more NO2 molecules are thermodynamically and kinetically favorable to form N2O4. Moreover, the fast release of NO2 molecules is achieved when 2.0 hole is applied to Cu/G as evidenced by the ab initio molecular dynamic simulation. Importantly, the adsorption of NO2 can be monitored real-time based on the conductivity change induced by the charge transfer and orbital hybridization. The behaviors and electronic monitoring of NO2 adsorption provide valuable guidance for future application of Cu/G as a potential material for NO2 fixation.

20.
Nanomicro Lett ; 12(1): 138, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34138125

RESUMO

Highly thermo-conductive aqueous medium is a crucial premise to demonstrate high-performance thermal-related applications. Graphene has the diamond comparable thermal conductivity, while the intrinsic two-dimensional reality will result in strong anisotropic thermal conductivity and wrinkles or even crumples that significantly sacrifices its inherent properties in practical applications. One strategy to overcome this is to use three-dimensional (3D) architecture of graphene. Herein, 3D graphene structure with covalent-bonding nanofins (3D-GS-CBF) is proposed, which is then used as the filler to demonstrate effective aqueous medium. The thermal conductivity and thermal conductivity enhancement efficiency of 3D-GS-CBF (0.26 vol%) aqueous medium can be as high as 2.61 W m-1 K-1 and 1300%, respectively, around six times larger than highest value of the existed aqueous mediums. Meanwhile, 3D-GS-CBF can be stable in the solution even after 6 months, addressing the instability issues of conventional graphene networks. A multiscale modeling including non-equilibrium molecular dynamics simulations and heat conduction model is applied to interpret experimental results. 3D-GS-CBF aqueous medium can largely improve the solar vapor evaporation rate (by 1.5 times) that are even comparable to the interfacial heating system; meanwhile, its cooling performance is also superior to commercial coolant in thermal management applications.

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