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1.
Nano Lett ; 24(9): 2719-2726, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38377427

RESUMO

Plasmonic Cu@semiconductor heteronanocrystals (HNCs) have many favorable properties, but the synthesis of solid structures is often hindered by the nanoscale Kirkendall effect. Herein, we present the use of an atomically thin Au3Cu palisade interlayer to reduce lattice mismatch and mediate the Kirkendall effect, enabling the successive topological synthesis of Cu@Au3Cu@Ag, Cu@Au3Cu@Ag2S, and further transformed solid Cu@Au3Cu@CdS core-shell HNCs via cation exchange. The atomically thin and intact Au3Cu palisade interlayer effectively modulates the diffusion kinetics of Cu atoms as demonstrated by experimental and theoretical investigations and simultaneously alleviates the lattice mismatch between Cu and Ag as well as Cu and CdS. The Cu@Au3Cu@CdS HNCs feature exceptional crystallinity and atomically organized heterointerfaces between the plasmonic metal and the semiconductor. This results in the efficient plasmon-induced injection of hot electrons from Cu@Au3Cu into the CdS shell, enabling the Cu@Au3Cu@CdS HNCs to achieve high activity and selectivity for the photocatalytic reduction of CO2 to CO.

2.
Langmuir ; 40(22): 11642-11649, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38761148

RESUMO

Colloidal quantum dots (QDs) have exceptional fluorescence properties. Overcoming aggregation-induced quenching and enhancing the fluorescence of colloidal QDs have remained a challenging issue in this field. In this study, composite hollow nanospheres composed of Au nanoparticles (NPs) and CdS:Ag-doped QDs were successfully constructed through controlled microemulsion-based cooperative assembly. This method harnessed the localized surface plasmon resonance (LSPR) effect of Au NPs nearby doped QDs, resulting in enhanced doped QD fluorescence and the observation of the Purcell effect. The composite hollow nanospheres show a fluorescence enhancement compared to that of the pure CdS:Ag QDs. The enhanced fluorescence was demonstrated to come from the synergetic enhancement of the absorption and emission transition of the doped QDs. This approach provides a feasible technological pathway to address the challenge of improving the fluorescence performance of the doped QDs.

3.
Ecol Appl ; 34(4): e2969, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38562107

RESUMO

Drought and nitrogen enrichment could profoundly affect the productivity of semiarid ecosystems. However, how ecosystem productivity will respond to different drought scenarios, especially with a concurrent increase in nitrogen availability, is still poorly understood. Using data from a 4-year field experiment conducted in a semiarid temperate steppe, we explored the responses of aboveground net primary productivity (ANPP) to different drought scenarios and nitrogen addition, and the underlying mechanisms linking soil properties, plant species richness, functional diversity (community-weighted means of plant traits, functional dispersion) and phylogenetic diversity (net relatedness index) to ANPP. Our results showed that completely excluding precipitation in June (1-month intense drought) and reducing half the precipitation amount from June to August (season-long chronic drought) both significantly reduced ANPP, with the latter having a more negative impact on ANPP. However, reducing half of the precipitation frequency from June to August (precipitation redistribution) had no significant effect on ANPP. Nitrogen addition increased ANPP irrespective of drought scenarios. ANPP was primarily determined by soil moisture and nitrogen availability by regulating the community-weighted means of plant height, rather than other aspects of plant diversity. Our findings suggest that precipitation amount is more important than precipitation redistribution in influencing the productivity of temperate steppe, and nitrogen supply could alleviate the adverse impacts of drought on grassland productivity. Our study advances the mechanistic understanding of how the temperate grassland responds to drought stress, and implies that management strategies to protect tall species in the community would be beneficial for maintaining the productivity and carbon sequestration of grassland ecosystems under climate drought.


Assuntos
Secas , Pradaria , Nitrogênio , Nitrogênio/metabolismo , Plantas/classificação , Solo/química , China
4.
Inorg Chem ; 63(22): 10358-10365, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38767279

RESUMO

Core-shell nanocrystals (C-S NCs) are an essential class of materials whose structural engineering has attracted wide attention due to their tunable optical and electrical properties, especially noble metal@semiconductor (NMS) C-S NCs with flexible plasmon-exciton coupling. Due to their diverse critical applications, especially aqueous biological applications, herein we propose an aqueous topological strategy enabled by cation exchange reactions (CER) to synthesize various plasmonic Au@semiconductor C-S NCs, in which environmentally friendly triphenylphosphine (TPP) is used as an initiator instead of inflammable tributyl phosphine (TBP). The introduction of the milder, solid TPP facilitated a new aqueous CER strategy for synthesizing Au@semiconductor NCs with tailored chalcogenide compositions and morphologies. For example, the as-synthesized Au@ZnS C-S NRs had better absorption and biocompatibility and exhibited excellent photodynamic therapy efficacy.

5.
Ecotoxicol Environ Saf ; 273: 116097, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38367605

RESUMO

BACKGROUND: Constrained by no proper way to assess cumulative exposure, the joint effect of air pollution cumulative exposure doses on childhood asthma and wheezing (AW) was not understood. OBJECTIVE: To assess the association between cumulative exposure to multiple air pollutants in early life and childhood AW. METHODS: We designed a nested case-control study based on the birth cohort in Jinan City. Children with AW followed up within 2 years after birth were treated as cases, and non-cases in this cohort were treated as the control source population, and the propensity score matching method was used to match each case to 5 controls. We calculated the individual cumulative outdoor exposure doses for each period using an inverse distance weighted model, alongside the complex Simpson's formula, accounting for outdoor time and respiratory volume. The Least absolute shrinkage and selection operator (Lasso) regression was performed to screen for covariates. To analyze the joint effects of pollutants, we employed the weighted quantile sum (WQS) regression model in conjunction with conditional logistic regression. RESULTS: 84 cases and 420 controls were included in this study. The odds ratio (OR) with 95% confidence interval (CI) of the impact of cumulative exposure (mg/m3) after birth on childhood AW was 1.78 (1.15-2.74) for SO2, 1.69 (1.11-2.57) for NO2, and 1.65 (1.09-2.52) for PM2.5, respectively. Furthermore, with each 25th percentile increase in the WQS index, the overall risk of cumulative doses for six pollutants exposure after birth on AW increased by an adjusted OR of 1.10 (1.03, 1.18), and SO2, PM2.5, and NO2 contributed the most to the WQS index. However, no statistically significant association was found between cumulative exposure to all pollutants before birth and childhood AW. CONCLUSIONS: There was a joint effect of the cumulative exposure dose of outdoor air pollutants after birth on AW in children aged 0-2 years. And traffic-related pollutants (SO2, PM2.5, and NO2) make a greater contribution to the joint effect.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Asma , Poluentes Ambientais , Criança , Humanos , Pré-Escolar , Poluentes Atmosféricos/análise , Sons Respiratórios , Dióxido de Nitrogênio , Estudos de Casos e Controles , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Asma/epidemiologia , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Material Particulado/análise
6.
Nano Lett ; 23(7): 2905-2914, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-36961203

RESUMO

Strain engineering is an attractive strategy for improving the intrinsic catalytic performance of heterogeneous catalysts. Manipulating strain on the short-range atomic scale to the local structure of the catalytic sites is still challenging. Herein, we successfully achieved atomic strain modulation on ultrathin layered vanadium oxide nanoribbons by an ingenious intercalation chemistry method. When trace sodium cations were introduced between the V2O5 layers (Na+-V2O5), the V-O bonds were stretched by the atomically strained vanadium sites, redistributing the local charges. The Na+-V2O5 demonstrated excellent photooxidation performance, which was approximately 12 and 14 times higher than that of pristine V2O5 and VO2, respectively. Complementary spectroscopy analysis and theoretical calculations confirmed that the atomically strained Na+-V2O5 had a high surficial charge density, improving the activation of oxygen molecules and contributing to the excellent photocatalytic property. This work provides a new approach for the rational design of strain-equipped catalysts for selective photooxidation reactions.

7.
Angew Chem Int Ed Engl ; 63(23): e202404911, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38581238

RESUMO

Developing efficient and earth-abundant catalysts for CO2 fixation to high value-added chemicals is meaningful but challenging. Styrene carbonate has great market value, but the cycloaddition of CO2 to styrene oxide is difficult due to the high steric hindrance and weak electron-withdrawing ability of the phenyl group. To utilize clean energy (such as optical energy) directly and effectively for CO2 value-added process, we introduce earth-abundant Ti single-atom into the mesoporous nitrogen, oxygen-doped carbon nanosheets (Ti-CNO) by a two-step method. The Ti-CNO exhibits excellent photothermal catalytic activities and stability for cycloaddition of CO2 and styrene oxide to styrene carbonate. Under light irradiation and ambient pressure, an optimal Ti-CNO produces styrene carbonate with a yield of 98.3 %, much higher than CN (27.1 %). In addition, it shows remarkable stability during 10 consecutive cycles. Its enhanced catalytic performance stems from the enhanced photothermal effect and improved Lewis acidic/basic sites exposed by the abundant mesopores. The experiments and theoretical simulations demonstrate the styrene oxide⋅+ and CO2⋅- radicals generated at the Lewis acidic (Tiδ+) and basic sites of Ti-CNO under light irradiation, respectively. This work furnishes a strategy for synthesizing advanced single-atom catalysts for photo-thermal synergistic CO2 fixation to high value products via a cycloaddition pathway.

8.
Cancer Immunol Immunother ; 72(5): 1261-1272, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36427086

RESUMO

Tumor response T cells, which have specific T cell receptor (TCR) rearrangements in tumor-infiltrating lymphocytes, determine their ability to interact with the mutation-derived neoantigens presented by antigen-presenting cells. Little is known about the genetic alterations related to specific TCR clones in non-small cell lung cancer (NSCLC) patients who have an epidermal growth factor receptor (EGFR) mutation. In this study, tumor tissues were collected from 101 patients with stage II/III resectable NSCLC with an EGFR mutation (57 patients were treated with gefitinib and 44 were treated with chemotherapy) in the ADJUVANT-CTONG1104 trial for high-throughput TCRß V region and exome sequencing. Ten clonal TCRs were associated with EGFR exon 19 deletion (del), EGFR exon 21 mutation (L858R), RB1 alteration, TP53 exon 4/5 missense mutation, TP53 nonsense mutation, or copy number gains in NKX2-1 and CDK4. Among the TCRs, there was frequent use of Vß20-1Jß2-3 specifically for EGFR exon 19 del or Vß9Jß2-1 specifically for EGFR exon 21 mutation (L858R), and these were significantly associated with favorable overall survival (OS) for NSCLC patients harboring EGFR exon 19 del or exon 21 L858R, particularly in the adjuvant gefitinib setting. Moreover, in comparison with the chemotherapy-preferable (CP) group, higher frequencies of Vß20-1Jß2-3 and Vß9Jß2-1 were found in the highly TKI-preferable (HTP) or TKI-preferable (TP) groups. Altogether, we identified ten TCR rearrangements specific for genetic alterations in NSCLC. Importantly, high abundance Vß20-1Jß2-3 or Vß9Jß2-1 may be an immune biomarker for guiding adjuvant gefitinib decisions for NSCLC patients harboring EGFR exon 19 del or EGFR exon 21 L858R.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Receptores ErbB/genética , Gefitinibe/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Mutação , Inibidores de Proteínas Quinases/uso terapêutico , Receptores de Antígenos de Linfócitos T/imunologia
9.
Cancer Immunol Immunother ; 72(4): 881-893, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36121452

RESUMO

BACKGROUND: Immunotherapy has largely improved clinical outcome of patients with esophageal squamous cell carcinoma (ESCC). However, a proportion of patients still fail to benefit. Thus, biomarkers predicting therapeutic resistance and underlying mechanism needs to be investigated. METHODS: Transcriptomic profiling was applied in FFPE tissues from 103 ESCC patients, including surgical samples from 66 treatment-naïve patients with long-term follow-up, and endoscopic biopsies from 37 local advanced ESCC cases receiving neoadjuvant immunotherapy plus chemotherapy. Unsupervised clustering indicated an aggressive phenotype with mesenchymal character in 66 treatment-naïve samples. Univariant logistic regression was applied to identify candidate biomarkers potentially predicted resistance to neoadjuvant immunotherapy within the range of mesenchymal phenotype enriched genes. These biomarkers were further validated by immunohistochemistry. Putative mechanisms mediating immunotherapy resistance, as indicated by microenvironment and immune cell infiltration, were evaluated by transcriptomic data, and validated by multiplex immunofluorescence. RESULTS: PLEK2 and IFI6, highly expressed in mesenchymal phenotype, were identified as novel biomarkers relating to non-MPR in neoadjuvant immunotherapy cohort [PLEK2high, OR (95% CI): 2.15 (1.07-4.33), P = 0.032; IFI6high, OR (95% CI): 2.21 (1.16-4.23), P = 0.016). PLEK2high and IFI6 high ESCC patients (versus low expressed patients) further exhibit higher chance of non-major pathological remissions (90%, P = 0.004) in neoadjuvant immunotherapy cohort and high mortality (78.9%, P = 0.05), poor prognosis in retrospective cohort. PLEK2high/IFI6high ESCC recapitulated mesenchymal phenotype, characterized by extracellular matrix composition and matrix remodeling. In addition, PLEK2high or IFI6high ESCC displayed an immune-unfavored microenvironment, represented by positive correlating with regulatory T cells, Helper 2 T cell as well as less infiltration of B cells, effector T cells and mast cells. CONCLUSIONS: PLEK2 and IFI6 was discovered of first time to identify a distinct ESCC subpopulation cannot be benefited from neoadjuvant immunotherapy and present a poor survival, which putatively associated with mesenchymal and immune-suppressive microenvironment.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Carcinoma de Células Escamosas do Esôfago/terapia , Carcinoma de Células Escamosas do Esôfago/patologia , Estudos Retrospectivos , Terapia Neoadjuvante , Prognóstico , Biomarcadores Tumorais/genética , Imunoterapia , Microambiente Tumoral , Proteínas Mitocondriais/uso terapêutico , Proteínas de Membrana/uso terapêutico
10.
Small ; 19(30): e2300539, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37060228

RESUMO

Photoacoustic imaging (PAI) and imaging-guided photothermal therapy (PTT) in the second near-infrared window (NIR-II, 1000-1700 nm) have received increasing attention owing to their advantages of greater penetration depth and higher signal-to-noise ratio. Plasmonic nanomaterials with tunable optical properties and strong light absorption provide an alternative to dye molecules, showing great prospects for phototheranostic applications. In this review, the research progress in principally modulating the optical properties of plasmonic nanomaterials, especially affecting parameters such as size, morphology, and surface chemical modification, is introduced. The commonly used plasmonic nanomaterials in the NIR-II window, including noble metals, semiconductors, and heterostructures, are then summarized. In addition, the biomedical applications of these NIR-II plasmonic nanomaterials for PAI and PTT in phototheranostics are highlighted. Finally, the perspectives and challenges for advancing plasmonic nanomaterials for practical use and clinical translation are discussed.


Assuntos
Nanopartículas , Nanoestruturas , Técnicas Fotoacústicas , Terapia Fototérmica , Técnicas Fotoacústicas/métodos , Nanoestruturas/uso terapêutico , Fototerapia/métodos , Diagnóstico por Imagem , Nanomedicina Teranóstica/métodos , Nanopartículas/química
11.
Small ; 19(11): e2207235, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36650994

RESUMO

Developing robust and highly active bifunctional electrocatalysts for overall water splitting is critical for efficient sustainable energy conversion. Herein, heteroatom-doped amorphous/crystalline ruthenium oxide-based hollow nanocages (M-ZnRuOx (MCo, Ni, Fe)) through delicate control of composition and structure is reported. Among as-synthesized M-ZnRuOx nanocages, Co-ZnRuOx nanocages deliver an ultralow overpotential of 17 mV at 10 mA cm-2 and a small Tafel slope of 21.61 mV dec-1 for hydrogen evolution reaction (HER), surpassing the commercial Pt/C catalyst, which benefits from the synergistic coupling effect between electron regulation induced by Co doping and amorphous/crystalline heterophase structure. Moreover, the incorporation of Co prevents Ru from over-oxidation under oxygen evolution reaction (OER) operation, realizing the leap from a monofunctional to multifunctional electrocatalyst and then Co-ZnRuOx nanocages exhibit remarkable OER catalytic activity as well as overall water splitting performance. Combining theory calculations with spectroscopy analysis reveal that Co is not only the optimal active site, increasing the number of exposed active sites while also boosting the long-term durability of catalyst by modulating the electronic structure of Ru atoms. This work opens a considerable avenue to design highly active and durable Ru-based electrocatalysts.

12.
Environ Res ; 226: 115687, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36925033

RESUMO

BACKGROUND: Given differences in vulnerability of children in early life, a life course approach to asthma and wheezing (AW) in young children caused by ozone (O3) is not fully understood. METHODS: We conducted a birth cohort in Jinan, China from 2018 to 2021 to elucidate the onset model of childhood AW due to O3 exposure. An inverse distance weighted model was used for individual exposure assessment. The time-dependent Cox proportional-hazard model and logistic model were used to investigate the effects of O3 exposure on AW. Principal component analysis, interaction analysis, and distributed lag model were used to analyze the life course approach. RESULTS: The cumulative incidence rate for AW among 6501 children aged 2 was 1.4%. A high level of O3 was related to AW (HR: 2.10, 95% CI: 1.31, 3.37). Only O3 exposure after birth was associated with AW, with an OR of 1.82 (1.08, 3.12), after adjusting for the effect before birth. Furthermore, adjusting for other air pollutants, the HR for the individual effect of high O3 exposure on AW was 2.44 (1.53, 3.89). Interestingly, P values for interactions for O3 and the principal components of other pollutants, as well as the characteristic variable of open windows were less than 0.1. Moreover, an increase in the IQR of O3 exposure at the 31st to 37th weeks before birth and the 1st to 105th weeks after birth was associated with an increase in the HRs for AW. CONCLUSIONS: High-level of O3 exposure after birth could lead to AW among young children. Importantly, the AW onset model may include the risk factors accumulation and the sensitive period model. Specifically, there are two sensitive windows in early life, and the correlated insults between the high level of O3 and other pollutants as well as open windows in the asthma-inducing effect.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Asma , Poluentes Ambientais , Ozônio , Feminino , Humanos , Criança , Pré-Escolar , Ozônio/análise , Poluição do Ar/análise , Coorte de Nascimento , Estudos Prospectivos , Acontecimentos que Mudam a Vida , Sons Respiratórios/etiologia , Material Particulado/análise , Poluentes Atmosféricos/análise , Asma/induzido quimicamente , Asma/epidemiologia , China/epidemiologia , Poluentes Ambientais/análise , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise
13.
Angew Chem Int Ed Engl ; 62(34): e202304488, 2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37394662

RESUMO

Constructing electrocatalysts with p-block elements is generally considered rather challenging owing to their closed d shells. Here for the first time, we present a p-block-element bismuth-based (Bi-based) catalyst with the co-existence of single-atomic Bi sites coordinated with oxygen (O) and sulfur (S) atoms and Bi nanoclusters (Biclu ) (collectively denoted as BiOSSA /Biclu ) for the highly selective oxygen reduction reaction (ORR) into hydrogen peroxide (H2 O2 ). As a result, BiOSSA /Biclu gives a high H2 O2 selectivity of 95 % in rotating ring-disk electrode, and a large current density of 36 mA cm-2 at 0.15 V vs. RHE, a considerable H2 O2 yield of 11.5 mg cm-2 h-1 with high H2 O2 Faraday efficiency of ∼90 % at 0.3 V vs. RHE and a long-term durability of ∼22 h in H-cell test. Interestingly, the experimental data on site poisoning and theoretical calculations both revealed that, for BiOSSA /Biclu , the catalytic active sites are on the Bi clusters, which are further activated by the atomically dispersed Bi coordinated with O and S atoms. This work demonstrates a new synergistic tandem strategy for advanced p-block-element Bi catalysts featuring atomic-level catalytic sites, and the great potential of rational material design for constructing highly active electrocatalysts based on p-block metals.

14.
J Am Chem Soc ; 144(41): 18995-19007, 2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36214519

RESUMO

The development of rechargeable Na-S batteries is very promising, thanks to their considerably high energy density, abundance of elements, and low costs and yet faces the issues of sluggish redox kinetics of S species and the polysulfide shuttle effect as well as Na dendrite growth. Following the theory-guided prediction, the rare-earth metal yttrium (Y)-N4 unit has been screened as a favorable Janus site for the chemical affinity of polysulfides and their electrocatalytic conversion, as well as reversible uniform Na deposition. To this end, we adopt a metal-organic framework (MOF) to prepare a single-atom hybrid with Y single atoms being incorporated into the nitrogen-doped rhombododecahedron carbon host (Y SAs/NC), which features favorable Janus properties of sodiophilicity and sulfiphilicity and thus presents highly desired electrochemical performance when used as a host of the sodium anode and the sulfur cathode of a Na-S full cell. Impressively, the Na-S full cell is capable of delivering a high capacity of 822 mAh g-1 and shows superdurable cyclability (97.5% capacity retention over 1000 cycles at a high current density of 5 A g-1). The proof-of-concept three-dimensional (3D) printed batteries and the Na-S pouch cell validate the potential practical applications of such Na-S batteries, shedding light on the development of promising Na-S full cells for future application in energy storage or power batteries.

15.
Small ; 18(13): e2105883, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34918467

RESUMO

Atomically dispersed metal sites (ADMSs) attract immense attention because they can be used in the fields of energy and environmental protection as they are characterized by high atomic utilization efficiency and exhibit high activity. Various supports for anchoring isolated metal atoms are developed to construct ADMSs characterized by highly stable and well-defined structures. This can be achieved by increasing the number of anchoring sites and reinforcing metal-support interactions. MXenes, a new series of 2D nanomaterials, exhibit promising potential in stabilizing isolated metal atoms because of their large specific surface areas and unique surface properties. The high conductivity and hydrophilicity of MXenes can be attributed to the nature of surface functionalization and the properties of tunable structures of the materials. Benefiting from these excellent properties, MXenes can find their applications in various fields. Herein, the precise characterization methods that can be followed to study ADMSs, the construction of MXene-supported ADMSs using theoretical predictions, and experimental modulation strategies are summarized, and their corresponding applications in electrocatalysis, organocatalysis, and advanced battery systems are systematically illustrated. It is hoped that this review will provide insights that can be used for the further development of MXene-supported ADMSs.

16.
Langmuir ; 38(11): 3469-3479, 2022 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-35275491

RESUMO

It is highly challenging to design low-cost, efficient electrocatalysts for both oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). Herein, a hierarchical heterostructure was constructed on three-dimensional (3D) Ni foam, which contains Ni3S2 nanorods decorated with both Co9S8 and amorphous MoSx nanosheets and Ni3S2 nanowires decorated with amorphous MoSx nanosheets, namely, MoSx@Co9S8@Ni3S2/NF. The synergistic effects from the strong interactions of the heterointerface and unique hierarchical heterostructure endow the MoSx@Co9S8@Ni3S2/NF with abundant active sites and effective mass and electron transport pathways, resulting in excellent activity toward both HER and OER in 1 M KOH. It only gives a low overpotential of 76.5 mV to achieve 10 mA cm-2 for HER and a low overpotential of 310 mV to achieve 100 mA cm-2 for OER. Based on the superior catalytic activity of MoSx@Co9S8@Ni3S2/NF for OER and HER, we demonstrated the activity of overall water splitting using MoSx@Co9S8@Ni3S2/NF as both the anode and cathode. It shows a higher catalytic activity for overall water splitting with a low cell voltage of 1.52 V at 10 mA cm-2 than commercial Pt/C/NF||IrO2/NF (1.61 V) and superior stability. This work provides a platform for the design and preparation of efficient electrocatalysts with various hierarchical heterostructures.

17.
Inorg Chem ; 61(9): 3989-3996, 2022 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-35191681

RESUMO

Engineering the structure of core-shell colloidal semiconductor nanoparticles (CSNPs) is attractive due to the potential to enhance photo-induced charge transfer and induce favorable optical and electronic properties. Nonetheless, the sensitivity of telluride CSNPs to high temperatures makes it challenging to precisely modulate their surface crystallinity. Herein, we have developed an efficient strategy for synthesizing telluride CSNPs with thin amorphous shells using aqueous cation exchange (ACE). By changing the synthesis temperature in the range of 40-110 °C, the crystallinity of the CdTe nanoparticles was controllable from perfect crystals with no detectable amorphous shell (c-CdTe) to a core-shell structure with a crystalline CdTe NP core covered by an amorphous shell of tunable thickness up to 7-8 nm (c@a-CdTe). A second ACE step transformed c@a-CdTe to crystalline CdTe@HgTe core-shell NPs. The c@a-CdTe nanoparticles synthesized at 60 °C and having a 4-5 nm thick amorphous shell exhibited the highest surface-enhanced Raman scattering activity with a high enhancement factor around 8.82 × 105, attributed to the coupling between the amorphous shell and the crystalline core.

18.
Chem Rev ; 120(4): 2123-2170, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-31971378

RESUMO

In the past decades, great strides have been made in the synthesis of hybrid nanocrystals (HNCs) consisting of two or more disparate subunits (such as metals and/or semiconductors) joined through nanointerfaces, which are intriguing due to their exceptional functionalities that cannot be achieved by single-component nanosystems. The promising and versatile applications of these HNCs are closely dependent on the structural and electronic properties of the nanointerface between subunits. This is because the compatibility of the lattice structures between subunits not only determines the synthetic accessibility and growth mechanisms of the HNCs on the thermodynamic basis but also influences their interfacial characteristics (atomic arrangement, lattice mismatch-induced strain or defects), configurations, crystallinity, and the synergistic interplay of different subunits at the nanoscale. As a result, nanointerface chemistry has attracted intense scientific endeavors worldwide and spurred the rapid development of the lattice-mismatch-directed precise synthesis. This review gives an overview of the main strategies developed for delicate design and fabrication of core-shell HNCs under different degrees of lattice mismatch (from 0.2% to larger than 50%), including epitaxial seeded growth, nanoscale cation exchange, cation exchange-facilitated nonepitaxial growth, etc. Moreover, as for the core-shell HNCs with small (<5%) or moderate lattice mismatch (∼5-20%), the significance of the lattice-strain control at the nanointerface in maneuvering their functions toward desired applications are discussed in detail. Regarding the core-shell HNCs with large lattice mismatch (>20%), the challenges in precise synthesis, the promising solutions enabled by cation exchange-facilitated nonepitaxial growth, and the enhanced applications of the resulting HNCs with strain-free nanointerface are elaborated. We conclude with a personal perspective on the significance and urgency of fully harnessing the effects of lattice mismatch to further advance the science of synthesis and application of HNCs.

19.
Environ Res ; 209: 112884, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35131319

RESUMO

The vitality and diversity of soil microbial metabolism are the core of soil function expression, cover crop is an environmentally friendly agricultural production practice; however, shifts in soil microbial metabolic activities along time gradient of cover crop remain unclear. Here, we used metagenomic and biological techniques to investigate soil microbial potential function and carbon (C) source utilization capacity in the time series of white clover (WC, Trifolium repens L.) for 6, 10, and 15 years in a typical semiarid apple orchard. Conventional tillage (CT) was taken as the control. This study demonstrated that living mulch 6 years of WC had little effect on soil microbial functions. However, after 10 and 15 years of crop cover, an enrichment of genes related to amino acid metabolism, carbon cycle, and nitrogen metabolism was observed in soil microorganisms. Furthermore, average well color development (AWCD) was increased in 10 and 15 years of cover crop, soil microbiome exhibited a stronger preference for carbohydrates, amino acids, and polymers as C sources. The results mainly provided insight into the variation character of microbial metabolic function under increasing duration of cover crop.


Assuntos
Microbiologia do Solo , Solo , Agricultura/métodos , Biodegradação Ambiental , Carbono , Solo/química
20.
J Nanobiotechnology ; 20(1): 172, 2022 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-35366907

RESUMO

BACKGROUND: The identification of indeterminate pulmonary nodules (IPNs) following a low-dose computed tomography (LDCT) is a major challenge for early diagnosis of lung cancer. The inadequate assessment of IPNs' malignancy risk results in a large number of unnecessary surgeries or an increased risk of cancer metastases. However, limited studies on non-invasive diagnosis of IPNs have been reported. METHODS: In this study, we identified and evaluated the diagnostic value of circulating small extracellular vesicle (sEV) microRNAs (miRNAs) in patients with IPNs that had been newly detected using LDCT scanning and were scheduled for surgery. Out of 459 recruited patients, 109 eligible patients with IPNs were enrolled in the training cohort (n = 47) and the test cohort (n = 62). An external cohort (n = 99) was used for validation. MiRNAs were extracted from plasma sEVs, and assessed using Small RNA sequencing. 490 lung adenocarcinoma samples and follow-up data were used to investigate the role of miRNAs in overall survival. RESULTS: A circulating sEV miRNA (CirsEV-miR) model was constructed from five differentially expressed miRNAs (DEMs), showing 0.920 AUC in the training cohort (n = 47), and further identified in the test cohort (n = 62) and in an external validation cohort (n = 99). Among five DEMs of the CirsEV-miR model, miR-101-3p and miR-150-5p were significantly associated with better overall survival (p = 0.0001 and p = 0.0069). The CirsEV-miR scores were calculated, which significantly correlated with IPNs diameters (p < 0.05), and were able to discriminate between benign and malignant PNs (diameter ≤ 1 cm). The expression patterns of sEV miRNAs in the benign, adenocarcinoma in situ/minimally invasive adenocarcinoma, and invasive adenocarcinoma subgroups were found to gradually change with the increase in aggressiveness for the first time. Among all DEMs of the three subgroups, five miRNAs (miR-30c-5p, miR-30e-5p, miR-500a-3p, miR-125a-5p, and miR-99a-5p) were also significantly associated with overall survival of lung adenocarcinoma patients. CONCLUSIONS: Our results indicate that the CirsEV-miR model could help distinguish between benign and malignant PNs, providing insights into the feasibility of circulating sEV miRNAs in diagnostic biomarker development. TRIAL REGISTRATION: Chinese Clinical Trials: ChiCTR1800019877. Registered 05 December 2018, https://www.chictr.org.cn/showproj.aspx?proj=31346 .


Assuntos
MicroRNA Circulante , Vesículas Extracelulares , MicroRNAs , Biomarcadores Tumorais/genética , MicroRNA Circulante/genética , Detecção Precoce de Câncer , Vesículas Extracelulares/genética , Humanos , MicroRNAs/genética
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