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1.
J Environ Sci (China) ; 148: 336-349, 2025 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-39095169

RESUMO

Catalytic destruction is an ascendant technology for the abatement of volatile organic compounds (VOCs) originating from solvent-based industrial processes. The varied composition tends to influence each VOC's catalytic behavior in the reaction mixture. We investigated the catalytic destruction of multi-component VOCs including dichloromethane (DCM) and ethyl acetate (EA), as representatives from pharmaceutical waste gases, over co-supported HxPO4-RuOx/CeO2 catalyst. A mutual inhibitory effect relating to concentrations because of competitive adsorption was verified in the binary VOCs oxidation and EA posed a more negative effect on DCM oxidation owing to EA's superior adsorption capacity. Preferential adsorption of EA on acidic sites (HxPO4/CeO2) promoted DCM activation on basic sites (O2-) and the dominating EA oxidation blocked DCM's access to oxidation centers (RuOx/CeO2), resulting in boosted monochloromethane yield and increased chlorine deposition for DCM oxidation. The impaired redox ability of Ru species owing to chlorine deposition in turn jeopardized deep oxidation of EA and its by-products, leading to increased gaseous by-products such as acetic acid originating from EA pyrolysis. Notably, DCM at low concentration slightly promoted EA conversion at low temperatures with or without water, consistent with the enhanced EA adsorption in co-adsorption analyses. This was mainly due to that DCM impeded the shielding effect of hydrolysate deposition from rapid EA hydrolysis depending on the decreased acidity. Moreover, water benefited EA hydrolysis but decreased CO2 selectivity while the generated water derived from EA was likely to affect DCM transformation. This work may provide theoretical guidance for the promotion of applied catalysts toward industrial applications.


Assuntos
Acetatos , Cério , Cloreto de Metileno , Acetatos/química , Catálise , Cloreto de Metileno/química , Cério/química , Compostos Orgânicos Voláteis/química , Adsorção , Oxirredução , Rutênio/química
2.
Chem Soc Rev ; 53(16): 8379-8423, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39007174

RESUMO

Nitrous oxide (N2O) decomposition is increasingly acknowledged as a viable strategy for mitigating greenhouse gas emissions and addressing ozone depletion, aligning significantly with the UN's sustainable development goals (SDGs) and carbon neutrality objectives. To enhance efficiency in treatment and explore potential valorization, recent developments have introduced novel N2O reduction catalysts and pathways. Despite these advancements, a comprehensive and comparative review is absent. In this review, we undertake a thorough evaluation of N2O treatment technologies from a holistic perspective. First, we summarize and update the recent progress in thermal decomposition, direct catalytic decomposition (deN2O), and selective catalytic reduction of N2O. The scope extends to the catalytic activity of emerging catalysts, including nanostructured materials and single-atom catalysts. Furthermore, we present a detailed account of the mechanisms and applications of room-temperature techniques characterized by low energy consumption and sustainable merits, including photocatalytic and electrocatalytic N2O reduction. This article also underscores the extensive and effective utilization of N2O resources in chemical synthesis scenarios, providing potential avenues for future resource reuse. This review provides an accessible theoretical foundation and a panoramic vision for practical N2O emission controls.

3.
Environ Sci Technol ; 58(29): 12823-12845, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-38954631

RESUMO

Nitrate, a prevalent water pollutant, poses substantial public health concerns and environmental risks. Electrochemical reduction of nitrate (eNO3RR) has emerged as an effective alternative to conventional biological treatments. While extensive lab work has focused on designing efficient electrocatalysts, implementation of eNO3RR in practical wastewater settings requires careful consideration of the effects of various constituents in real wastewater. In this critical review, we examine the interference of ionic species commonly encountered in electrocatalytic systems and universally present in wastewater, such as halogen ions, alkali metal cations, and other divalent/trivalent ions (Ca2+, Mg2+, HCO3-/CO32-, SO42-, and PO43-). Notably, we categorize and discuss the interfering mechanisms into four groups: (1) loss of active catalytic sites caused by competitive adsorption and precipitation, (2) electrostatic interactions in the electric double layer (EDL), including ion pairs and the shielding effect, (3) effects on the selectivity of N intermediates and final products (N2 or NH3), and (4) complications by the hydrogen evolution reaction (HER) and localized pH on the cathode surface. Finally, we summarize the competition among different mechanisms and propose future directions for a deeper mechanistic understanding of ionic impacts on eNO3RR.


Assuntos
Nitratos , Nitratos/química , Catálise , Íons , Águas Residuárias/química , Oxirredução , Poluentes Químicos da Água/química
4.
Environ Sci Technol ; 58(26): 11812-11821, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38897924

RESUMO

We developed a simple strategy for preparing IrSn bimetallic clusters encapsulated in pure silicon zeolites via a one-pot hydrothermal synthesis by using diethylamine as a stabilizing agent. A series of investigations verified that metal species have been confined successfully in the inner of MFI zeolites. IrSn bimetallic cluster catalysts were efficient for the CO selective catalytic reduction of NOx in the presence of excess O2. Furthermore, the 13CO temperature-programmed surface reaction results demonstrated that NO2 and N2O could form when most of the CO was transformed into CO2 and that Sn modification could passivate CO oxidation on the IrSn bimetallic clusters, leading to more reductants that could be used for NOx reduction at high temperatures. Furthermore, SO2 can also influence the NOx conversion by inhibiting the oxidation of CO. This study provides a new strategy for preparing efficient environmental catalysts with a high dispersion of metal species.


Assuntos
Oxirredução , Oxigênio , Zeolitas , Zeolitas/química , Catálise , Oxigênio/química , Monóxido de Carbono/química , Estanho/química , Óxidos de Nitrogênio/química
5.
J Environ Sci (China) ; 145: 128-138, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38844313

RESUMO

Zeolites are a promising support for Pd catalysts in lean methane (CH4) combustion. Herein, three types of zeolites (H-MOR, H-ZSM-5 and H-Y) were selected to estimate their structural effects and deactivation mechanisms in CH4 combustion. We show that variations in zeolite structure and surface acidity led to distinct changes in Pd states. Pd/H-MOR with external high-dispersing Pd nanoparticles exhibited the best apparent activity, with activation energy (Ea) at 73 kJ/mol, while Pd/H-ZSM-5 displayed the highest turnover frequency (TOF) at 19.6 × 10-3 sec-1, presumably owing to its large particles with more step sites providing active sites in one particle for CH4 activation. Pd/H-Y with dispersed PdO within pore channels and/or Pd2+ ions on ion-exchange sites yielded the lowest apparent activity and TOF. Furthermore, Pd/H-MOR and Pd/H-ZSM-5 were both stable under a dry condition, but introducing 3 vol.% H2O caused the CH4 conversion rate on Pd/H-MOR drop from 100% to 63% and that on Pd/H-ZSM-5 decreased remarkably from 82% to 36%. The former was shown to originate from zeolite structural dealumination, and the latter principally owed to Pd aggregation and the loss of active PdO.


Assuntos
Metano , Paládio , Zeolitas , Zeolitas/química , Metano/química , Catálise , Paládio/química , Modelos Químicos
6.
Environ Sci Technol ; 58(18): 8086-8095, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38666813

RESUMO

Secondary pollution remains a critical challenge for the catalytic destruction of chlorinated volatile organic compounds (CVOCs). By employing experimental studies and theoretical calculations, we provide valuable insights into the catalytic behaviors exhibited by ceria rods, cubes, and octahedra for monochloromethane (MCM) destruction, shedding light on the elementary reactions over facet-dependent CeO2. Our findings demonstrate that CeO2 nanorods with the (110) facet exhibit the best performance in MCM destruction, and the role of vacancies is mainly to form a longer distance (4.63 Å) of frustrated Lewis pairs (FLPs) compared to the stoichiometric surface, thereby enhancing the activation of MCM molecules. Subsequent molecular orbital analysis showed that the adsorption of MCM mainly transferred electrons from the 3σ and 4π* orbitals to the Ce 4f orbitals, and the activation was mainly caused by weakening of the 3σ bonding orbitals. Furthermore, isotopic experiments and theoretical calculations demonstrated that the hydrogen chloride generated is mainly derived from methyl in MCM rather than from water, and the primary function of water is to form excess saturated H on the surface, facilitating the desorption of generated hydrogen chloride.


Assuntos
Oxigênio , Catálise , Oxigênio/química , Cério/química , Adsorção , Compostos Orgânicos Voláteis/química
7.
RSC Adv ; 14(20): 14068-14079, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38686283

RESUMO

In this study, Ag/AgBr-O-gCN samples with ternary Z-type heterojunctions were prepared by in situ photoreduction using water as the reducing agent for generating Ag/AgBr active species and oxygen doping. The experimental results indicated that Ag/AgBr-O-gCN degraded trimethylamine by nearly 100% in half an hour and maintained 90% of its original activity after five cycles. The kinetic constant of Ag/AgBr-O-gCN was excellent at 0.0928 min-1, 3.8 times that of gCN, 2.3 times that of Ag/AgBr-gCN, and 1.9 times that of O-gCN. Unlike Ag/AgBr-gCN photoreduced by methanol, gCN was used as an electron donor in the aqueous solution during the photoreduction process, and oxidation sites between the gCN skeleton and Ag/AgBr were formed for constructing the heterojunction system. The Z-type heterojunction system was established by introducing a suitable size of Ag nanoparticles as the recombination center to keep indirect contact between gCN and AgBr. This effectively reduced the electron-hole recombination rate and caused activity enhancement. This study offers a novel idea for the construction of a ternary heterojunction.

8.
Environ Sci Technol ; 58(20): 8976-8987, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38653761

RESUMO

Nitrous oxide (N2O) is a potent greenhouse gas with a high global warming potential, emphasizing the critical need to develop efficient elimination methods. Electrocatalytic N2O reduction reaction (N2ORR) stands out as a promising approach, offering room temperature conversion of N2O to N2 without the production of NOx byproducts. In this study, we present the synthesis of a copper-based single-atom catalyst featuring atomic Cu on nitrogen-doped carbon black (Cu1-NCB). Attributed to the highly dispersed single-atom Cu sites and the effective suppression of the hydrogen evolution reaction, Cu1-NCB demonstrated an optimal N2 faradaic efficiency (82.1%) and yield rate (3.53 mmol h-1 mgmetal-1) at -0.2 and -0.5 V vs RHE, respectively, outperforming previously reported N2ORR electrocatalysts. Further, a gas diffusion electrode cell was employed to improve mass transfer and achieved a 28.6% conversion rate of 30% N2O with only a 14 s residence time, demonstrating the potential for practical application. Density functional theory calculations identified Cu-N4 as the crucial active site for N2ORR, highlighting the significance of the unsaturated coordination and metal-support electronic structure. O-terminal adsorption of N2O was favored, and the dissociative adsorption (*ON2 → *O + N2) was the rate-determining step. These findings reveal the broad prospects of N2O decomposition via electrocatalysis.


Assuntos
Carbono , Cobre , Nitrogênio , Óxido Nitroso , Nitrogênio/química , Catálise , Óxido Nitroso/química , Carbono/química , Cobre/química , Oxirredução
9.
Eur Arch Otorhinolaryngol ; 281(6): 3143-3156, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38507078

RESUMO

PURPOSE: To look at the diagnostic value of the CELSR receptor 3 (CELSR3) gene in head and neck squamous cell carcinoma (HNSCC) and its effect on tumor immune invasion, which is important for enhancing HNSCC treatment. METHODS: Several bioinformatics tools were employed to investigate CELSR3's putative oncogenic pathway in HNSCC, and datasets from The Tumor Genome Atlas (TCGA), Tumor Immune Estimation Resource (TIMER), Gene Expression Profile Interaction Analysis (GEPIA) and LinkedOmics were extracted and evaluated. CELSR3 has been linked to tumor immune cell infiltration, immunological checkpoints, and immune-related genes. CELSR3's putative roles were investigated using Gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and pathway enrichment analysis. The expression level of CELSR3 in HNSCC tissues and cells was detected by RT-qPCR. The effects of CELSR3 on proliferation of HNSCC cells were detected by CCK-8 assay. RESULTS: CELSR3 was shown to be expressed differently in different types of cancer and normal tissues. CELSR3 gene expression was linked to pN-stage and pM-stage. Patients with high CELSR3 expression also have a well prognosis. CELSR3 expression was found to be an independent predictive factor for HNSCC in both univariate and multivariate Cox regression analyses. We discovered the functional network of CELSR3 in HNSCC using GO and KEGG analysis. CELSR3 expression levels were found to be favorably associated with immune cell infiltration levels. Furthermore, CELSR3 expression levels were significantly correlated with the expression levels of many immune molecules, such as MHC genes, immune activation genes, chemokine receptors, and chemokines. CELSR3 is highly expressed in HNSCC tissues and cells. CELSR3 overexpression significantly inhibited the proliferation of HNSCC cells. CELSR3 expression may affect the immune microenvironment and, as a result, the prognosis of HNSCC. CONCLUSION: CELSR3 expression is elevated in HNSCC tumor tissues, and high CELSR3 expression is associated with well prognosis, which inhibited the proliferation of NHSCC cells. CELSR3 has the potential to influence tumor formation by controlling tumor-infiltrating cells in the tumor microenvironment (TME). As a result, CELSR3 may have diagnostic significance in HNSCC.


Assuntos
Biomarcadores Tumorais , Caderinas , Neoplasias de Cabeça e Pescoço , Carcinoma de Células Escamosas de Cabeça e Pescoço , Microambiente Tumoral , Feminino , Humanos , Masculino , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/imunologia , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/metabolismo , Linfócitos do Interstício Tumoral/imunologia , Prognóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/imunologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Microambiente Tumoral/imunologia , Microambiente Tumoral/genética , Caderinas/genética , Caderinas/metabolismo , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo
10.
Materials (Basel) ; 17(6)2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38541594

RESUMO

Barium and iridium supported on Zeolite Socony Mobil-5 (ZSM-5) are efficient catalysts for the selective catalytic reduction of nitric oxide by carbon monoxide (CO-SCR), with enhanced cyclic stability. The introduction of Ba hindered the oxidation of metallic Ir active species and enabled Ir to maintain an active metallic state, thereby preventing a decrease in catalytic activity in the CO-SCR reaction. Moreover, the Ba modification increased the NO adsorption of the catalyst, further improving the catalytic activity. Owing to the better anti-oxidation ability of Ir0 in IrBa0.2/ZSM-5(27) than in Ir/ZSM-5(27), IrBa0.2/ZSM-5(27) showed better stability than Ir/ZSM-5(27). Considering that all samples in the present study were tested to simulate actual flue gases (such as sintering flue gas and coke oven flue gas), NH3 was introduced into the reaction system to serve as an extra reductant for NOx. The NOx conversion to N2 (77.1%) was substantially improved using the NH3-CO-SCR system. The proposed catalysts and reaction systems are promising alternatives for treating flue gas, which contains considerable amounts of NOx and CO in oxygen-enriched environments.

11.
Environ Sci Technol ; 58(12): 5557-5566, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38412381

RESUMO

Wet flue gas denitrification offers a new route to convert industrial nitrogen oxides (NOx) into highly concentrated nitrate wastewater, from which the nitrogen resource can be recovered to ammonia (NH3) via electrochemical nitrate reduction reactions (NITRRs). Low-cost, scalable, and efficient cathodic materials need to be developed to enhance the NH3 production rate. Here, in situ electrodeposition was adopted to fabricate a foamy Cu-based heterojunction electrode containing both Cu-defects and oxygen vacancy loaded Cu2O (OVs-Cu2O), which achieved an NH3 yield rate of 3.59 mmol h-1 cm-2, NH3 Faradaic efficiency of 99.5%, and NH3 selectivity of 100%. Characterizations and theoretical calculations unveiled that the Cu-defects and OVs-Cu2O heterojunction boosted the H* yield, suppressed the hydrogen evolution reaction (HER), and served as dual reaction sites to coherently match the tandem reactions kinetics of NO3-to-NO2 and NO2-to-NH3. An integrated system was further built to combine wet flue gas denitrification and desulfurization, simultaneously converting NO and SO2 to produce the (NH4)2SO4 fertilizer. This study offers new insights into the application of low-cost Cu-based cathode for electrochemically driven wet denitrification wastewater valorization.


Assuntos
Amônia , Águas Residuárias , Nitratos/química , Dióxido de Nitrogênio , Desnitrificação , Eletrodos
12.
Eur Arch Otorhinolaryngol ; 281(1): 427-440, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37688682

RESUMO

PURPOSE: To investigate Src-like adaptor 2 gene (SLA2) expression in head and neck squamous cell carcinoma (HNSCC), its potential prognostic value, and its effect on immune cell infiltration. METHODS: Through a variety of bioinformatics analyses, we extracted and analyzed data sets from the Cancer Genome Atlas (TCGA), Tumor Immune Estimation Resource (TIMER), and Gene Expression Profile Interaction Analysis (GEPIA) to analyze the correlation between SLA2 and the prognosis, immune checkpoint, tumor microenvironment (TME) and immune cell infiltration of HNSCC, and to explore its potential oncogenic mechanism. To further explore the potential role of SLA2 in HNSCC by Gene ontology (GO) functional annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. RESULTS: SLA2 messenger ribonucleic acid (mRNA) levels were increased in HNSCC tumor tissues compared with normal tissues. In addition, we found that SLA2 may be an independent prognostic factor for HNSCC, and high SLA2 expression is associated with favorable prognosis in HNSCC. SLA2 expression was positively correlated with B cells, cluster of differentiation 8-positive T cells (CD8 + T cells), cluster of differentiation 4-positive T cells (CD4 + T cells), macrophages, neutrophil and dendritic cells infiltration. SLA2 has also been shown to co-express immune-related genes and immune checkpoints. Significant GO term analysis by Gene Set Enrichment Analysis (GSEA) indicated that genes correlated with SLA2 were located mainly in the side of membrane, receptor complex, secretory granule membrane, endocytic vesicle, membrane region, and endosome membrane, where they were involved in leukocyte cell-cell adhesion, response to interferon-gamma, and regulation of immune effector process. These related genes also served as antigen binding, cytokine receptor activity, phosphatidylinositol 3-kinase activity, peptide receptor activity, Src homology domain 3 (SH3) domain binding, and cytokine receptor binding. KEGG pathway analysis demonstrated that these genes related to SLA2 were mainly enriched in signal pathways, such as hematopoietic cell lineage, cell adhesion molecules (CAMs), natural killer cell mediated cytotoxicity, measles, and chemokine signaling pathway. CONCLUSIONS: SLA2 is increased in HNSCC, and high SLA2 expression is associated with favorable prognosis. SLA2 may affect tumor development by regulating tumor infiltrating cells in TME. SLA2 may be a potential target for immunotherapy.


Assuntos
Neoplasias de Cabeça e Pescoço , Microambiente Tumoral , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Prognóstico , Neoplasias de Cabeça e Pescoço/genética , Receptores de Citocinas
13.
Environ Sci Technol ; 58(2): 1369-1377, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38048160

RESUMO

An improved fundamental understanding of active site structures can unlock opportunities for catalysis from conceptual design to industrial practice. Herein, we present the computational discovery and experimental demonstration of a highly active surface-phosphorylated ceria catalyst that exhibits robust chlorine tolerance for catalysis. Ab initio molecular dynamics (AIMD) calculations and in situ near-ambient pressure X-ray photoelectron spectroscopy (in situ NAP-XPS) identified a predominantly HPO4 active structure on CeO2(110) and CeO2(111) facets at room temperature. Importantly, further elevating the temperature led to a unique hydrogen (H) atom hopping between coordinatively unsaturated oxygen and the adjacent P═O group of HPO4. Such a mobile H on the catalyst surface can effectively quench the chlorine radicals (Cl•) via an orientated reaction analogous to hydrogen atom transfer (HAT), enabling the surface-phosphorylated CeO2-supported monolithic catalyst to exhibit both expected activity and stability for over 68 days during a pilot test, catalyzing the destruction of a complex chlorinated volatile organic compound industrial off-gas.


Assuntos
Cloro , Oxigênio , Catálise , Temperatura , Hidrogênio
14.
Medicine (Baltimore) ; 102(51): e36771, 2023 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-38134081

RESUMO

BACKGROUND: Based on network pharmacology, molecular docking, and vitro assays, investigate the probable pharmacological mechanism of Dioscoreae bulbiferae and Bruceae fructus in the treatment of laryngocarcinoma. METHODS: The active components and targets of Dioscoreae bulbiferae and Bruceae fructus were retrieved from the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform database. Targets linked with laryngocarcinoma were gathered from the GeneCards, DisGeNET, and DrugBank databases. The String database was utilized to build a protein-protein interaction network of common medication and illness targets, after which the core targets were filtered out. The Metascape database served for gene ontology enrichment and Kyoto encyclopedia of genes and genomes pathway analysis of common targets. AutoDock then performed molecular docking between the essential component and the vital target. To investigate the biological effects of diosbulbin B, we assessed the viability of laryngocarcinoma cells after diosbulbin B therapy using the Mahalanobis Taguchi system technique. Following that, we looked at how diosbulbin B affected colony formation after 14 days of culture of treated cells. Flow cytometry was utilized to detect apoptosis in order to examine the influence of diosbulbin B on laryngocarcinoma cell apoptosis. RESULTS: According to a study of the literature, the fundamental components of Dioscoreae bulbiferae and Bruceae fructus in the treatment of laryngocarcinoma include brusatol and diosbulbin B, which may operate on core targets such as cyclin D1, Cyclin Dependent Kinase Inhibitor 1A, and E2F Transcription Factor 1. The significant pathways discovered using Kyoto encyclopedia of genes and genomes enrichment analysis were the phosphoinositide 3-kinase-protein kinase B signaling route, the tumor necrosis factor signaling pathway, and so on. These pathways primarily influence the development and prognosis of laryngeal cancer by controlling cell growth, cell proliferation, angiogenesis, tumorigenesis, and metastasis. The molecular docking studies revealed that the affinity between the heart and crucial targets was robust. The results of vitro assays indicate that diosbulbin B suppressed Hep-2 cell activity in a concentration-dependent manner. Besides, diosbulbin B has powerful antiproliferative properties in Hep-2 cells. Flow cytometry results showed that diosbulbin B promoted laryngocarcinoma cell apoptosis in a concentration-dependent manner. CONCLUSION: The article delivered a preliminary discussion of the probable mechanism of Dioscoreae bulbiferae and Bruceae fructus in the treatment of laryngocarcinoma, which can serve as a theoretical basis and evidence for subsequent experimental investigation.


Assuntos
Medicamentos de Ervas Chinesas , Farmacologia em Rede , Humanos , Simulação de Acoplamento Molecular , Fosfatidilinositol 3-Quinases , Projetos de Pesquisa , Medicina Tradicional Chinesa , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico
15.
RSC Adv ; 13(45): 31820-31834, 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37908663

RESUMO

In this study, alkali-metal-doped crystalline g-C3N4 with an enriched cyano group was synthesized using the molten salt method and used for the visible-light photocatalytic degradation of methylamine (MA), a common organic amine compound with a low odor threshold. Different types and proportions of melting salts (Li, K, and Na) were added during secondary calcination to regulate the morphology, crystallinity, and surface defects of graphitic carbon nitride (g-C3N4). With molten salt treatment matched the melting point of the binary salt system, a cyano group and alkali metal co-doped crystalline g-C3N4 with a high surface area and good crystallinity were prepared. Co-decorating the alkali metal and cyano groups on crystalline g-C3N4 facilitated the adsorption of MA, realized an excellent photo-charge transfer efficiency, and generated more superoxide radicals. Compared with pristine g-C3N4 (PCN), the apparent rate constant of LiK15 : 5-CCN for the degradation of MA increased by 10.2 times and the degradation efficiency of 1000 ppm MA gas was 93.1% after 90 min of irradiation with visible light, whereas the degradation efficiency of PCN was 19.2%.

16.
Artigo em Inglês | MEDLINE | ID: mdl-38032489

RESUMO

The goal of this study is to look into the pharmacological mechanism of Bruceae Fructus in conjunction with GEO, network pharmacology, and in vitro assays for the treatment of laryngeal cancer to provide theoretical support for its therapeutic use. The active components and matching targets of Bruceae Fructus were retrieved from the TCMSP database, while genes linked with laryngeal cancer were obtained from the GEO, GeneCards, DisGeNET, and DrugBank databases. Besides, the components and targets were supplemented by literatures in PubMed database. Cytoscape software was used to create the active ingredients-target network diagram. The String database was used to build the PPI network. Following that, the core targets were subjected to GO enrichment and KEGG pathway analysis using the DAVID database. Finally, AutoDock was used to perform molecular docking between the core components and the core targets. To investigate the biological effects of beta-sitosterol, the viability of laryngeal cancer cells was assessed after beta-sitosterol therapy using the MTS technique. Following that, how beta-sitosterol affected colony formation after 14 days of culture of treated cells was researched. Flow cytometry was utilized to detect apoptosis to examine the influence of beta-sitosterol on laryngeal cancer cell apoptosis, and then detected mRNA and protein expression levels of 10 key genes by RT-qPCR and Western Blot assay. There were 1258 laryngeal cancer-related genes and 15 Bruceae Fructus components, with beta-sitosterol and luteolin serving as key components. Bruceae Fructus' primary targets against laryngeal cancer were IL6, JUN, TNF, IL2, IL4, IFNG, RELA, TP53, CDKN1A, and AKT1. GO enrichment yielded 41 CC, 78 MF, and 383 BP. Platinum drug resistance, the PI3K-Akt signaling pathway, the p53 signaling pathway, apoptosis, the HIF-1 signaling pathway, and 147 additional pathways have been added to KEGG. The results of molecular docking revealed that the core components had a high affinity for the core target. The results of the cell experiment indicate that beta-sitosterol suppressed Hep-2 cell activity in a concentration-dependent manner. Besides, beta-sitosterol has powerful antiproliferative properties in Hep-2 cells. Flow cytometry results showed that beta-sitosterol promoted laryngeal cancer cell apoptosis in a concentration-dependent manner. The results of RT-qPCR and Western Blot assay showed that the mRNA and protein expression levels of TP53, JUN, TNF-α, CDKN1A, and IL-2 were significantly up-regulated after beta-sitosterol treatment, while the mRNA and protein expression levels of RELA, AKT1, IL-6, IFNG, and IL-4 were significantly down-regulated. This study integrating GEO, network pharmacology, and in vitro assays investigated the probable mechanism of Bruceae Fructus' anti-laryngeal cancer activity, which can give a theoretical foundation for additional future animal experiments.

17.
Angew Chem Int Ed Engl ; 62(49): e202310191, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-37849070

RESUMO

The development of oxidation catalysts that are resistant to sulfur poisoning is crucial for extending the lifespan of catalysts in real-working conditions. Herein, we describe the design and synthesis of oxide-metal interaction (OMI) catalyst under oxidative atmospheres. By using organic coated TiO2 , an oxide/metal inverse catalyst with non-classical oxygen-saturated TiO2 overlayers were obtained at relatively low temperature. These catalysts were found to incorporate ultra-small Pd metal and support particles with exceptional reactivity and stability for CO oxidation (under 21 vol % O2 and 10 vol % H2 O). In particular, the core (Pd)-shell (TiO2 ) structured OMI catalyst exhibited excellent resistance to SO2 poisoning, yielding robust CO oxidation performance at 120 °C for 240 h (at 100 ppm SO2 and 10 vol % H2 O). The stability of this new OMI catalyst was explained through density functional theory (DFT) calculations that interfacial oxygen atoms at Pd-O-Ti sites (of oxygen-saturated overlayers) serve as non-metal active sites for low-temperature CO oxidation, and change the SO2 adsorption from metal(d)-to-SO2 (π*) back-bonding to much weaker σ(Ti-S) bonding.

18.
Environ Sci Technol ; 57(33): 12513-12522, 2023 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-37542459

RESUMO

Catalytic elimination of toxic nitrile waste gas is of great significance for preserving the atmospheric environment, but achieving resource utilization during its destruction has been less explored. Herein, this study proposed a universal strategy for nitrile waste gas purification and NH3 generation simultaneously. The developed silver single-atom-doped ceria nanorod (Ag1/R-CeO2) was endowed with near complete mineralization and around 90% NH3 yield at 300-350 °C for the catalytic oxidation of both acetonitrile and acrylonitrile. The introduction of the Ag single atom created more surface oxygen vacancies, thereby promoting water activation to form abundant surface hydroxyl groups. As a benefit from this, the hydrolysis reaction of nitrile to generate NH3 was accelerated. Meanwhile, the electron transfer effect from the Ag atom to Ce and hydroxyl species facilitated NH3 desorption, which inhibited the oxidation of NH3. Moreover, the increased surface oxygen vacancies also promoted the mineralization of hydrolysis carbonaceous intermediates to CO2. In contrast, the Ag nanoparticle-modified sample possessed stronger reducibility and NH3 adsorption, leading to the excessive oxidation of NH3 to N2 and NOx. This work provided a useful guidance for resourceful purification of nitrile waste gas.


Assuntos
Cério , Nanopartículas Metálicas , Amônia , Prata , Nitrilas , Catálise
19.
Angew Chem Int Ed Engl ; 62(42): e202310525, 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37653523

RESUMO

C-H dissociation and C-C coupling are two key steps in converting CH4 into multi-carbon compounds. Here we report a synergy of Au and Ag to greatly promote C2 H6 formation over Au1 Ag single-atom alloy nanoparticles (Au1 Ag NPs)-modified ZnO catalyst via photocatalytic oxidative coupling of methane (POCM) with O2 and H2 O. Atomically dispersed Au in Au1 Ag NPs effectively promotes the dissociation of O2 and H2 O into *OOH, promoting C-H activation of CH4 on the photogenerated O- to form *CH3 . Electron-deficient Au single atoms, as hopping ladders, also facilitate the migration of electron donor *CH3 from ZnO to Au1 Ag NPs. Finally, *CH3 coupling can readily occur on Ag atoms of Au1 Ag NPs. An excellent C2 H6 yield of 14.0 mmol g-1 h-1 with a selectivity of 79 % and an apparent quantum yield of 14.6 % at 350 nm is obtained via POCM with O2 and H2 O, which is at least two times that of the photocatalytic system. The bimetallic synergistic strategy offers guidance for future catalyst design for POCM with O2 and H2 O.

20.
Environ Sci Technol ; 57(37): 14091-14099, 2023 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-37643464

RESUMO

Wet denitrification is a promising approach to control nitrogen oxides (NOx) produced in fossil fuel combustion. Yet, the highly concentrated nitrite (NO2-) wastewater generated poses a major threat to the aqueous environment. Here, iridium nanoclusters (d = 1.63 nm) deposited on TiO2 were applied for NO2- reduction to ammonia (NRA), showing an exceptional NH4+ selectivity of 95% and a production rate of 20.51 mgN·L-1·h-1, which held significant potential for NO2- wastewater purification and ammonia resource recovery. Notably, an interesting non-first-order NO2- hydrogenation kinetics was observed, which was further confirmed to result from the competitive adsorption mechanism between H2 and NO2- over iridium. The NRA pathways on the Ir(111) surface were explored via density functional theory calculations with the NO2-* → NO* → HNO* → HNOH* → H2NOH* → NH2* → NH3* identified as the most energetically favorable pathway and the NO* → HNO* confirmed as the rate-determining step. In situ DRIFTS further experimentally verified the generation of HNO* intermediate during NO* hydrogenation on Ir(111). To verify NRA kinetics at varied NO2- concentrations or H2 pressures, a kinetic model was derived based on the Langmuir-Hinshelwood competitive adsorption mechanism. These findings provide mechanistic insights into the NRA pathways on Ir nanocatalysts, which will be beneficial for wet denitrification waste stream decontamination and valorization.


Assuntos
Amônia , Nitritos , Hidrogenação , Adsorção , Irídio , Dióxido de Nitrogênio
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