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1.
Nano Lett ; 24(37): 11683-11689, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39225553

RESUMEN

Beyond noble metals and semiconductors, quasi-metals have recently been shown to be noteworthy substrates for surface enhanced Raman spectroscopy, and their excellent quasi-metal surface-enhanced Raman spectroscopy (SERS) sensing has demonstrated a wider range of application scenarios. However, the underlying mechanism behind the enhanced Raman activity is still unclear. Here, we demonstrate that surface hydroxyls play a crucial role in the enhancement of the SERS activity of quasi-metal nanostructures. As a demonstration material, quasi-metallic MoO2 single-crystal frameworks rich in surface hydroxyls have been shown to have 100 times higher SERS activity than MoO2 single-crystal frameworks without hydroxyl functionalization, with a Raman enhancement factor of up to 7.6 × 107. Experimental and first-principles density-functional theory calculation results show that the enhanced Raman activity can be attributed to an effective interfacial charge transfer within the MoO2/OH/molecule system.

2.
Med Res Rev ; 2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39171404

RESUMEN

Fenamates as classical nonsteroidal anti-inflammatory agents are widely used for relieving pain. Preclinical studies and epidemiological data highlight their chemo-preventive and chemotherapeutic potential for cancer. However, comprehensive reviews of fenamates in cancer are limited. To accelerate the repurposing of fenamates, this review summarizes the results of fenamates alone or in combination with existing chemotherapeutic agents. This paper also explores targets of fenamates in cancer therapy, including COX, AKR family, AR, gap junction, FTO, TEAD, DHODH, TAS2R14, ion channels, and DNA. Besides, this paper discusses other mechanisms, such as regulating Wnt/ß-catenin, TGF-ß, p38 MAPK, and NF-κB pathway, and the regulation of the expressions of Sp, EGR-1, NAG-1, ATF-3, ErbB2, AR, as well as the modulation of the tumor immune microenvironment. Furthermore, this paper outlined the structural modifications of fenamates, highlighting their potential as promising leads for anticancer drugs.

3.
Sci Rep ; 14(1): 17934, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39095382

RESUMEN

Based on double-compressed sampling, a hyperspectral spectral unmixing algorithm (SU_DCS) is proposed, which could directly complete the endmember extraction and abundance estimation. On the basis of the linear mixed model (LMM), we designed spatial and spectral sampling matrices, obtained spatial and spectral measurement data, and constructed a joint unmixing model containing endmember and abundance information. By using operator separation and Lagrangian multiplier algorithm, the endmember matrix, abundance matrix and remixing image can be quickly obtained by matrix operation. The parameters of the unmixing algorithm, including regularization parameter, convergence threshold and spatial sampling rate, are determined using synthetic simulated hyperspectral data. The proposed algorithm is applied to two kinds of real hyperspectral data, with or without ground truth, in order to verify the effectiveness and reliability of the algorithm. Firstly, we provide the performance of the algorithm on real datasets without ground truth. Compared with algorithm VCA_FCLS and algorithm CPPCA_VCA_FCLS, the endmember spectral curve extracted by the proposed SU_DCS is almost consistent with that obtained by VCA_FCLS, and is more smooth than that of obtained by CPPCA_VCA_FCLS. Additionally, the abundance estimation map estimated by the SU_DCS has consistency with the results obtained by VCA_FCLS. Moreover, the proposed SU_DCS has higher peak signal-to-noise ratio (PSNR) for remixing images with higher computational efficiency. Secondly, we provide the performance of the proposed algorithm on four real datasets with ground truth, including dataset Cuprite, dataset Samson, dataset Jasper and dataset Urban. We provide the results of endmember extraction and abundance estimation from the compressed data under different sampling rate conditions. The extracted endmember maintains good consistency with the true spectral curves, and the estimated abundance map can also maintain good spatial consistency with the ground truth. The comparison results with other four comparative algorithms also indicate that the proposed algorithm can obtain relatively accurate endmembers and abundance information from compressed data, the reliability and validity of the proposed algorithm have been proved. In summary, the main innovation of the proposed algorithm is that it can extract endmembers and estimate abundance with high accuracy from a small amount of measurement data.

4.
Nanomedicine (Lond) ; 19(14): 1297-1311, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39046514

RESUMEN

Aim: To develop a robust drug-delivery system using multi-arm amphiphilic block copolymers for enhanced efficacy in cancer therapy. Materials & methods: Two series of amphiphilic polymer micelles, PEG-b-PCLm and PEG-b-PCLm/TPGS, were synthesized. Doxorubicin (DOX) loading into the micelles was achieved via solvent dialysis. Results: The micelles displayed excellent biocompatibility, narrow size distribution, and uniform morphology. DOX-loaded micelles exhibited enhanced antitumor efficacy and increased drug accumulation at tumor sites compared with free DOX. Additionally, 4A-PEG47-b-PCL21/TPGS micelles effectively suppressed drug-resistant MCF-7/ADR cells. Conclusion: This study introduces a novel micelle formulation with exceptional serum stability and efficacy against drug resistance, promising for cancer therapy. It highlights innovative strategies for refining clinical translation and ensuring sustained efficacy and safety in vivo.


[Box: see text].


Asunto(s)
Doxorrubicina , Resistencia a Antineoplásicos , Micelas , Polietilenglicoles , Doxorrubicina/farmacología , Doxorrubicina/química , Humanos , Resistencia a Antineoplásicos/efectos de los fármacos , Polietilenglicoles/química , Animales , Células MCF-7 , Portadores de Fármacos/química , Ratones , Vitamina E/química , Vitamina E/farmacología , Femenino , Ratones Endogámicos BALB C , Polímeros/química , Ratones Desnudos , Antibióticos Antineoplásicos/farmacología , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/administración & dosificación , Poliésteres/química , Sistemas de Liberación de Medicamentos , Supervivencia Celular/efectos de los fármacos
5.
Water Res ; 262: 122097, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-39018583

RESUMEN

The UV/monochloramine (UV/NH2Cl) process, while efficiently eliminating micropollutants, produces toxic byproducts. This study utilized Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) to investigate molecular-level changes in natural organic matter (NOM) and to disclose formation pathways of nitro(so) and chloro byproducts in the UV/NH2Cl process. The UV/NH2Cl process significantly increased the saturation and oxidation levels and altered the elemental composition of NOM. Using 15N labeling and a screening workflow, nitro(so) byproducts with nitrogen originating from inorganic sources (i.e., reactive nitrogen species (RNS) and/or NH2Cl) were found to exhibit total intensities comparable to those from NOM. RNS, rather than NH2Cl, played a significant role in incorporating nitrogen into NOM. Through linkage analysis, nitro(so) addition emerged as an important reaction type among the 25 reaction types applied. By using phenol as a representative model compound, the nitro byproducts were confirmed to be mainly generated through the oxidation of nitroso byproducts instead of nitration. Machine learning and SHAP analysis further identified the major molecular indices distinguishing nitro(so) and chloro precursors from non-precursors. This study enhances our fundamental understanding of the mechanisms driving the generation of nitro(so) and chloro byproducts from their precursors in complex NOM during the UV/NH2Cl process.


Asunto(s)
Aprendizaje Automático , Rayos Ultravioleta , Espectrometría de Masas , Oxidación-Reducción , Cloraminas/química
6.
Water Res ; 256: 121564, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38615605

RESUMEN

Natural organic matter (NOM) is a major sink of radicals in advanced oxidation processes (AOPs) and understanding the transformation of NOM is important in water treatment. By using Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) in conjunction with machine learning, we comprehensively investigated the reactivity and transformation of NOM, and the formation of organosulfates during the UV/peroxydisulfate (PDS) process. After 60 min UV/PDS treatment, the CHO formula number and dissolved organic carbon concentration significantly decreased by 83.4 % and 74.8 %, respectively. Concurrently, the CHOS formula number increased substantially from 0.7 % to 20.5 %. Machine learning identifies DBE and AImod as the critical characteristics determining the reactivity of NOM during UV/PDS treatment. Furthermore, linkage analysis suggests that decarboxylation and dealkylation reactions are dominant transformation pathways, while the additions of SO3 and SO4 are also non-negligible. According to SHAP analysis, the m/z, number of oxygens, DBE and O/C of NOM were positively correlated with the formation of organosulfates in UV/PDS process. 92 organosulfates were screened out by precursor ion scan of HPLC-MS/MS and verified by UPLC-Q-TOF-MS, among which, 7 organosufates were quantified by authentic standards with the highest concentrations ranging from 2.1 to 203.0 ng L‒1. In addition, the cytotoxicity of NOM to Chinese Hamster Ovary (CHO) cells increased by 13.8 % after 30 min UV/PDS treatment, likely responsible for the formation of organosulfates. This is the first study to employ FT-ICR MS combined with machine learning to identify the dominant NOM properties affecting its reactivity and confirmed the formation of organosulfates from sulfate radical oxidation of NOM.


Asunto(s)
Aprendizaje Automático , Sulfatos , Sulfatos/química , Animales , Células CHO , Rayos Ultravioleta , Cricetulus , Espectrometría de Masas , Purificación del Agua/métodos , Oxidación-Reducción
7.
Colloids Surf B Biointerfaces ; 234: 113731, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38184944

RESUMEN

Cytokine storms characterized by excessive secretion of circulating cytokines and immune-cell hyperactivation are life-threatening systemic inflammatory syndromes. The new strategy is in great demand to inhibit the cytokine storm. Here, we designed a type of magnetically controlled nanorobots (MAGICIAN) by fusing neutrophil membranes onto Fe3O4 nanoparticles (Fe3O4NPs). In our study, the receptors of neutrophil membranes were successfully coated to the surface of Fe3O4NPs. The associated membrane functions of neutrophils were highly preserved. MAGICIAN could in vitro neutralize the inflammatory cytokines including interleukin 6 (IL-6), tumor necrosis factor α (TNF-α), and interferon γ (IFN-γ). Interestingly, MAGICIAN could be navigated to the liver sites under magnetic control and accelerated the cytokine clearance by the liver. Administration of MAGICIAN could efficiently relieve the inflammation in the acute lung injury mouse model. In addition, MAGICIAN displayed good biosafety in systemic administration. The present study provides a safe and convenient approach for the clearance of cytokine storms, indicating the potential for clinical application in acute lung injury therapy.


Asunto(s)
Lesión Pulmonar Aguda , Síndrome de Liberación de Citoquinas , Ratones , Animales , Citocinas , Factor de Necrosis Tumoral alfa , Lesión Pulmonar Aguda/tratamiento farmacológico , Interferón gamma
8.
Angew Chem Int Ed Engl ; 63(8): e202316936, 2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38179834

RESUMEN

Copper is a crucial catalyst in the synthesis of graphdiyne (GDY). However, as catalysts, the final fate of the copper ions has hardly been concerned, which are usually treated as impurities. Here, it is observed that after simple washing with water and ethanol, GDY still contains a certain amount of copper ions, and demonstrated that the copper ions are adsorbed at the atomic layers of GDY. Furthermore, we transformed in situ the copper ions into ultrathin Cu nanocrystals, and the obtained Cu/GDY hybrids can be generally converted into a series of metal/GDY hybrid materials, such as Ag/GDY, Au/GDY, Pt/GDY, Pd/GDY, and Rh/GDY. The Cu/GDY hybrids exhibit extraordinary surface enhanced Raman scattering effect and can be applied in pollutant efficient enrichment and detection.

9.
Nat Commun ; 14(1): 6318, 2023 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-37813839

RESUMEN

As a two-dimensional carbon allotrope, graphdiyne possesses a direct band gap, excellent charge carrier mobility, and uniformly distributed pores. Here, a surfactant-free growth method is developed to efficiently synthesize graphdiyne hollow microspheres at liquid‒liquid interfaces with a self-supporting structure, which avoids the influence of surfactants on product properties. We demonstrate that pristine graphdiyne hollow microspheres, without any additional functionalization, show a strong surface-enhanced Raman scattering effect with an enhancement factor of 3.7 × 107 and a detection limit of 1 × 10-12 M for rhodamine 6 G, which is approximately 1000 times that of graphene. Experimental measurements and first-principles density functional theory simulations confirm the hypothesis that the surface-enhanced Raman scattering activity can be attributed to an efficiency interfacial charge transfer within the graphdiyne-molecule system.

10.
Res Theory Nurs Pract ; 37(3): 386-400, 2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-37591529

RESUMEN

Background and Purpose: The main goal of hospice care is to improve the quality of life for people who are at the end-of-life phase. However, investigations on the awareness of hospice care among community-dwelling elderly participants are limited. This work aimed to reveal the awareness status of hospice care and explore the factors influencing the awareness rate among elderly participants. Methods: A questionnaire survey was conducted among individuals aged 60 years and above. Results: A total of 4,969 individuals aged 60 years and above were randomly selected from 48 primary medical institutions in Handan. The awareness rate of hospice care in the baseline survey was 19.3% (n = 959). All included individuals were divided into two groups in accordance with their awareness of hospice care. The awareness of hospice care among participants with low educational level, living alone, and afraid of talking about death was low (p < .05). Implications for Practice: The level of awareness of hospice care among community-dwelling elderly participants is low. The influencing factors included educational level, living status, and fear of talking about death. The community-dwelling elderly participants' awareness of hospice care must be improved. It is recommended that public medical education and training should be enhanced to improve knowledge and awareness of hospice care among community-dwelling elderly residents with low educational level, living alone, and afraid of talking about death.


Asunto(s)
Cuidados Paliativos al Final de la Vida , Anciano , Humanos , Escolaridad , Miedo , Vida Independiente , Calidad de Vida , Persona de Mediana Edad
11.
Small ; 19(28): e2300996, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36974579

RESUMEN

Due to the intrinsic layered structure, graphdiyne (GDY) strongly tends to form 2D materials, therefore, most of the current research are based on GDY 2D structures. Up to now, the synthesis of its ultrathin nanowires with a high aspect ratio has not been reported. Here, the ultrathin GDY nanowires with diameters below 3 nm are reported for the first time by a two-phase interface synthesis method, which has excellent crystallinity and an aspect ratio of more than 2500. Evidence shows that the GDY ultrathin nanowires are formed by the oriented-attachment mechanism of nanoparticles. The GDY ultrathin nanowires exhibit a significant quantum confinement effect, enhanced photoelectric effect, and promising applications in surface-enhanced Raman sensing.

12.
Nano Lett ; 23(7): 3023-3029, 2023 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-36996421

RESUMEN

Controlling the structure of graphdiyne (GDY) is crucial for the discovery of new properties and the development of new applications. Herein, the microemulsion synthesis of GDY hollow spheres (HSs) and multiwalled nanotubes composed of ultrathin nanosheets is reported for the first time. The formation of an oil-in-water (O/W) microemulsion is found to be a key factor controlling the growth of GDY. These GDY HSs have fully exposed surfaces because of the avoidance of overlapping between nanosheets, thereby showing an ultrahigh specific surface area of 1246 m2 g-1 and potential applications in the fields of water purification and Raman sensing.

13.
Rapid Commun Mass Spectrom ; 37 Suppl 1: e9509, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36945892

RESUMEN

RATIONALE: Rapid on-site detection of persistent organic pollutants (POP) is highly desirable for environmental protection. METHODS: Herein, a rapid on-site analytical workflow was developed for the investigation of polycyclic aromatic hydrocarbons and perfluorinated compounds using multiwalled carbon nanotube-modified paper spray ionization (PSI) coupled with a miniature ion trap mass spectrometer. Critical parameters regarding PSI and miniature mass spectrometry analysis were optimized. RESULTS: The analytical performance of the developed method was evaluated under optimized conditions, obtaining a short analysis duration of less than 1 min, sufficient linearity with correlation coefficients greater than 0.99, acceptable recovery rates of 93.1%-105.8% with relative standard deviations of between 3.5% and 10.3%, and reasonable sensitivity with limits of detection and quantitation of 2-200 and 5-500 µg/L, respectively. CONCLUSIONS: Considering these aspects, it was concluded that the present approach demonstrated a promising solution for rapid on-site detection of emerging POPs.

14.
J Transl Med ; 20(1): 583, 2022 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-36503542

RESUMEN

BACKGROUND: Growing evidence shows that C-Type Lectin Domain Containing 7A (Clec7a) may be involved into neuroinflammatory injury of various neurological diseases. However, its roles in neuropathic pain remain unclear. METHODS: A chronic constriction injury (CCI) rat model was constructed, and gene expression profilings in spinal cord tissues of CCI-insulted rats were detected by both microarray and RNA-seq studies. A series of bioinformatics analyses identified C/EBPß-Clec7a to be a candidate axis involved into neuropathic pain. Then, its roles in mechanical allodynia, and pathological and molecular changes during CCI progression were determined by various gain-of-function and loss-of-function experiments in vivo and in vitro. RESULTS: Significant upregulation of Clec7a at both mRNA and protein levels were verified in spinal cord tissues of CCI-insulted rats. Clec7a knockdown markedly attenuated CCI-induced mechanical allodynia, obstructed Syk, ERK and JNK phosphorylation, inhibited NLRP3 inflammasome and caspase-1 activation, GSDMD cleavage, and consequently reduced the release of pro-inflammatory cytokines (all P < 0.05). Mechanically, the rat Clec7a promoter was predicted to bind with transcription factor C/EBPß, confirmed by Luciferase assay and ChIP-qPCR. Both in vivo and in vitro assays demonstrated that C/EBPß knockdown significantly suppressed CCI- or LPS/ATP-induced Clec7a upregulation, and subsequently reduced Syk, ERK and JNK phosphorylation, NLRP3 oligomerization, caspase-1 activation, GSDMD expression and pyroptosis, which were markedly reversed by the co-transfection of Clec7a expression vector. CONCLUSIONS: This pre-clinical investigation reveals that C/EBPß-Clec7a axis may be a potential target for relieving neuropathic pain through alleviating neuroinflammation, paving its way for clinical translation as a promising approach for neuropathic pain therapy.


Asunto(s)
Inflamasomas , Neuralgia , Ratas , Animales , Inflamasomas/metabolismo , Proteína beta Potenciadora de Unión a CCAAT/genética , Proteína beta Potenciadora de Unión a CCAAT/metabolismo , Ratas Sprague-Dawley , Hiperalgesia/tratamiento farmacológico , Hiperalgesia/metabolismo , Hiperalgesia/patología , Caspasas , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo
15.
Foods ; 11(23)2022 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-36496722

RESUMEN

Food security is related to human wellbeing and sustainable development and an important guarantee for world peace. In the context of global climate change, increased food demand, resource depletion, conflicts, and frequent public health emergencies, food security is widely seen as one of the top challenges. Food security research has obvious interdisciplinary characteristics, involving a wide range of fields. We analyzed the literature on food security in the Web of Science core collection from 1991 to 2021, using bibliometric methods with the aid of the Biblioshiny software package. By collecting, screening, analyzing, and visually expressing the literature data, the following conclusions were drawn: (1) In the past 30 years, the annual number of publications on food security increased. The period can be divided into three stages: 1991-2003 as the budding period, 2004-2012 as the development period, and 2013-2020 as the high-yield and active period. The top three journals discussing food security issues are Food Security, Sustainability, and Food Policy, and these journals focus on the publication of comprehensive views from interdisciplinary perspectives. (2) Studies on food security cover 138 countries or regions. The top three countries in terms of the number of published articles are the United States, the United Kingdom, and China. Among the top 20 countries in terms of the number of published articles, European countries are highlighted. (3) Climate change, food security, agriculture, policy, and management are the other high-frequency keywords in the field of food security; climate change occurred 321 times. The word sub-Saharan Africa also occurred more frequently, indicating that food security in sub-Saharan Africa has attracted wide attention. (4) The food security theme mapping clearly showed the research status and future development trends of various topics in the field. Currently, food production, climate change, and sustainable development are the most popular themes. Research on food sovereignty, ecological agriculture, child obesity, and other aspects is an emerging field. (5) We predict that in the future, the field of food security may focus on the expansion and improvement of the food security evaluation system, the balance between sustainable development and food security goals, the improvement of agricultural production and management efficiency, and the research on government policies and strategies. Our results provide a reference for grasping the current situation, key research direction, and development trend in the field of food security.

16.
J Int Med Res ; 50(11): 3000605221134468, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36345170

RESUMEN

BACKGROUND: The diagnosis of constrictive pericarditis (CP) is challenging as there are currently no standard echocardiographic diagnostic criteria. In this retrospective case series, we analyzed and summarized the features of 25 patients with CP and proposed echocardiographic diagnostic criteria. It is hoped that the suggested criteria help professionals make decisions in their daily practice so that patients receive timely diagnosis and effective treatment. METHODS: Twenty-five patients with CP were selected for this retrospective study. The clinical and echocardiographic imaging data were analyzed and summarized, and echocardiographic diagnostic criteria for CP were proposed. RESULTS: The main clinical manifestations were fatigue, breathlessness, exertional dyspnea (88%), lower-limb edema (84%), hepatomegaly, and jugular vein filling (84%). Echocardiographic features comprised pericardial thickening (88%) and calcification (60%), pulmonary hypertension (52%), inferior vena cava dilation (80%), left and/or right atrial enlargement (100%), diastolic flattening of the left ventricular (LV) posterior wall (72%), septal shudder and bounce (64%), restrictive LV and right ventricular diastolic filling pattern (100%), early filling changes of mitral and tricuspid flow (80% and 60%, respectively), and mitral annulus reversus (73%). CONCLUSIONS: Echocardiography is a simple and valuable examination for CP. The echocardiographic diagnostic criteria are valid and worth promoting.


Asunto(s)
Pericarditis Constrictiva , Humanos , Pericarditis Constrictiva/diagnóstico por imagen , Estudios Retrospectivos , Ecocardiografía , Pericardio/diagnóstico por imagen , Válvula Mitral/diagnóstico por imagen
17.
Anal Chem ; 94(42): 14635-14641, 2022 10 25.
Artículo en Inglés | MEDLINE | ID: mdl-36239397

RESUMEN

The construction of open hot-spot structures that facilitate the entry of analytes is crucial for surface-enhanced Raman spectroscopy. Here, metallic niobium nitride (NbN) three-dimensional (3D) hierarchical networks with open nanocavity structure are first found to exhibit a strong visible-light localized surface plasmon resonance (LSPR) effect and extraordinary surface-enhanced Raman scattering (SERS) performance. The unique nanocavity structure allows easy entry of molecules, promoting the utilization of electromagnetic hot spots. The NbN substrate has a lowest detection limit of 1.0 × 10-12 M and a Raman enhancement factor (EF) of 1.4 × 108 for contaminants. Furthermore, the NbN hierarchical networks possess outstanding environmental durability, high signal reproducibility, and detection universality. The remarkable SERS sensitivity of the NbN substrate can be attributed to the joint effect of LSPR and interfacial charge transport (CT).


Asunto(s)
Niobio , Espectrometría Raman , Espectrometría Raman/métodos , Reproducibilidad de los Resultados , Resonancia por Plasmón de Superficie/métodos
18.
Anal Chem ; 94(40): 13659-13666, 2022 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-36163019

RESUMEN

It is of great significance for practical applications to directly convert readily available biomass carbon into three-dimensional (3D) porous carbon microspheres with a self-supporting structure. Herein, we report the convenient conversion of biomass carbon microspheres to hierarchical porous carbon microspheres (HP-CMSs) with a robust self-supporting framework structure. A general SiO2-induced etching mechanism is proposed for the formation of the HP-CMSs. Benefiting from this robust 3D self-supporting frame structure, these HP-CMSs have outstanding mechanical, chemical, and thermal stability. As a metal-free surface-enhanced Raman scattering (SERS) substrate with an ultrahigh specific surface area (4216 m2 g-1) and a high density of active sites, the HP-CMSs exhibit high sensitivity with a detection limit of 10-10 M and a Raman enhancement factor of 3.5 × 106. By integrating the enrichment and sensing functions of the HP-CMSs in a microfluidic channel, online high-throughput SERS detection of 20 samples within 5 min is achieved in a single channel, and the relative standard deviation of the signals between samples is only 5.1%. The current work develops a convenient preparation method that converts sustainable biomass carbon to 3D hierarchical porous carbon and provides a potential material for sensing, energy, catalysis, and other fields.


Asunto(s)
Carbono , Plata , Carbono/química , Microesferas , Porosidad , Dióxido de Silicio/química , Plata/química , Espectrometría Raman/métodos
19.
Sci Rep ; 12(1): 13206, 2022 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-35915213

RESUMEN

Functional fabrics with antibacterial performance are more welcome nowadays. However, the fabrication of functional fabrics with durable, steady performance via a cost-effective way remains a challenge. Polypropylene (denoted as PP) nonwoven fabric was modified by polyvinyl alcohol (denoted as PVA), followed by the in-situ deposition of silver nanoparticles (denoted as Ag NPs) to afford PVA-modified and Ag NPs-loaded PP (denoted as Ag/PVA/PP) fabric. The encapsulation of PP fiber by PVA coating contributes to greatly enhancing the adhesion of the loaded Ag NPs to the PP fiber, and the Ag/PVA/PP nonwoven fabrics exhibit significantly improved mechanical properties as well as excellent antibacterial activity against Escherichia coli (coded as E. coli). Typically, the Ag/PVA/PP nonwoven fabric obtained at a silver ammonia concentration of 30 mM has the best mechanical properties and the antibacterial rate reaches 99.99% against E. coli. The fabric retains excellent antibacterial activity even after washing for 40 cycles, showing prospects in reuse. Moreover, the Ag/PVA/PP nonwoven fabric could find promising application in industry, thanks to its desired air-permeability and moisture-permeability. In addition, we developed a roll-to-roll production process and conducted preliminary exploration to verify the feasibility of this method.


Asunto(s)
Nanopartículas del Metal , Plata , Antibacterianos/farmacología , Escherichia coli , Plata/farmacología , Staphylococcus aureus
20.
Artículo en Inglés | MEDLINE | ID: mdl-35955079

RESUMEN

Although coal is difficult to replace in the short term, the large-scale production and consumption of coal have significant impacts on the ecological environment. The severe disturbances, such as land excavation and occupation, that accompany the mining of mineral resources have caused dramatic changes in land cover and a significant pressure on the sensitive and fragile ecological environment. To analyze the temporal and spatial evolution trends and the differences in land use in different typical mining areas in Inner Mongolia, as well as the evaluation system and driving mechanisms of land use evolution, this study takes the typical open-pit coal mines in Inner Mongolia as the research objects and, based on the Google Earth Engine (GEE) platform, analyzes the dynamic evolution characteristics and driving factors of land use in typical open-pit coal mines in Inner Mongolia from 2001 to 2020. The change trend of land use in typical open-pit mining areas in Inner Mongolia for the past 20 years is obvious, with the highest fluctuations for grassland, mining land, cropland, and residential/industrial land. Land use in the open-pit coal mining area is greatly affected by mining factors. From the perspective of spatial variation, the most important driving factor is the distance from national roads and railways, followed by the annual average temperature and annual average precipitation and topographical conditions, such as elevation. In terms of policy, land reclamation and ecological restoration in mining areas have a positive impact on land use change. Improving the mechanism for environmental compensation in mining areas can promote the efficient and rational use of mining areas and the protection of ecosystems.


Asunto(s)
Minas de Carbón , Ecosistema , China , Carbón Mineral , Planeta Tierra , Monitoreo del Ambiente
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