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Despite the extensive development of non-noble metals for the N-alkylation of amines with alcohols, the exploitation of catalysts with high selectivity, activity, and stability still faces challenges. The controllable modification of single-atom sites through asymmetric coordination with a second heteroatom offers new opportunities for enhancing the intrinsic activity of transition metal single-atom catalysts. Here, we prepared the asymmetric N/P hybrid coordination of single-atom Co1-N3P1 by absorbing the Co-P complex on ZIF-8 using a concise impregnation-pyrolysis process. The catalyst exhibits ultrahigh activity and selectivity in the N-alkylation of aniline and benzyl alcohol, achieving a turnover number (TON) value of 3480 and a turnover frequency (TOF) value of 174-h. The TON value is 1 order of magnitude higher than the reported catalysts and even 37-fold higher than that of the homogeneous catalyst CoCl2(PPh3)2. Furthermore, the catalyst maintains its high activity and selectivity even after 6 cycles of usage. Controlling experiments and isotope labeling experiments confirm that in the asymmetric Co1-N3P1 system, the N-alkylation of aniline with benzyl alcohol proceeds via a transfer hydrogenation mechanism involving the monohydride route. Theoretical calculations prove that the superior activity of asymmetric Co1-N3P1 is attributed to the higher d-band energy level of Co sites, which leads to a more stable four-membered ring transition state and a lower reaction energy barrier compared to symmetrical Co1-N4.
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Transition-metal doping has been demonstrated to be effective for tuning the photocatalytic activity of semiconductors. Nonetheless, the impact of doping-induced trap states on the concentration of surface-reaching photoexcited charges remains a topic of debate. In this study, through time-resolved spectroscopies and kinetic analysis, we found that the concentration of surface-reaching photoholes (Ch+(surf)) in doped TiO2 nanoparticles sensitively relies on the type of dopants and their associated trap states. Among the studied dopants (Fe, Cu, and Co), Fe doping resulted in the most significant increase in Ch+(surf), nearly double that of Co or Cu doping. Fe-doping induced more effective hole trap states, acting as the mediator for interfacial charge transfer, thus accelerating charge separation and consequently enriching Ch+(surf). This work provides valuable insight into understanding and controlling Ch+(surf) in transition-metal-doped TiO2 materials.
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Efficient activation of CO2 at low temperature was achieved through the interface effect between In2O3 and ZrO2 by their geometric and electronic effects. The results show that 75In2O3-25ZrO2 (In2O3 : ZrO2 molar ratio of 3 : 1), as a catalyst for the reverse water gas shift reaction, can achieve 28% CO2 conversion with 96% CO selectivity at 400 °C, 0.1 MPa, a H2 : CO2 molar ratio of 3 : 1 and a gas hourly space velocity of 10 000 mL g-1 h-1. In situ FTIR experiments provide a basis for clarifying the pivotal role of formate (facilitated at In2O3-ZrO2 interface) in this reaction.
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Understanding the molecular mechanisms underlying tumorigenesis is crucial for developing effective cancer therapies. Here, we investigate the co-amplification of MED30 and MYC across diverse cancer types and its impact on oncogenic transcriptional programs. Transcriptional profiling of MYC and MED30 single or both overexpression/amplification revealed the over amount of MED30 lead MYC to a new transcriptional program that associate with poor prognosis. Mechanistically, MED30 overexpression/amplification recruits other Mediator components and binding of MYC to a small subset of novel genomic regulatory sites, changing the epigenetic marks and inducing the formation of new enhancers, which drive the expression of target genes crucial for cancer progression. In vivo studies in pancreatic ductal adenocarcinoma (PDAC) further validate the oncogenic potential of MED30, as its overexpression promotes tumor growth and can be attenuated by knockdown of MYC. Using another cancer type as an example, MED30 knockdown reduces tumor growth particularly in MYC high-expressed glioblastoma (GBM) cell lines. Overall, our study elucidates the critical role of MED30 overexpression in orchestrating oncogenic transcriptional programs and highlights its potential as a therapeutic target for MYC-amplified cancer.
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Transition-metal catalyzed tandem asymmetric reactions were powerful tools to access various chiral compounds. Many strategies have been developed for the coupling of 1,n-dienes with aryl halides via a tandem Heck/Tsuji-Trost process. However, the control of regio- and stereo-chemistry remains a challenging task. This minireview details the recent advances in the field of asymmetric Heck/Tsuji-Trost reactions catalyzed by palladium complex, which have opened new opportunities and expanded our understanding in this area of research in recent years.
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Single-component catalysts with integrated multiple reactive centers could work in concert to achieve enhanced activity tailored for specific catalytic reactions, but they remain underdeveloped. Herein, we report the construction of heterogeneous bimetallic porous coordination polymers (PCPs) containing both porphyrin and N-heterocyclic carbene (NHC) metal sites via the coordinative assembly of the NHC functionalities. Three heterobimetallic PCPs (TIPP-Zn-Pd, TIPP-Cu-Pd and TIPP-Ni-Pd) have been prepared to verify this facile synthetic strategy for the first time. In order to establish a cooperative action toward the catalytic CO2 cycloaddition with epoxides, an additional tetraalkylammonium bromide functionality has also been incorporated into these polymeric structures through the N-substituent of the NHC moieties. The resulting heterogeneous bimetallic catalyst TIPP-Zn-Pd exhibits the best catalytic performance in CO2 cycloaddition with styrene oxide (SO) under solvent-free conditions at atmospheric pressure and is applicable to a wide range of epoxides. More importantly, TIPP-Zn-Pd works smoothly and is recyclable in the absence of a cocatalyst under 1.0 MPa of CO2 at 60 °C. This indicates that TIPP-Zn-Pd is quite competitive with the reported heterogeneous catalysts, which typically require a high reaction temperature above 100 °C under cocatalyst-free conditions. Thus, this work provides a new approach to design heterogeneous bimetallic PCP catalysts for high-performance CO2 fixation under mild reaction conditions.
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The synthesis of low-temperature poly(heptazine imide) (PHI) presents a significant challenge. In this context, we have developed a novel low-temperature synthesis strategy for PHI in this work. This strategy involves the introduction of Na+ ions, which etch and disrupt the conjugated structure of carbon nitride (CN) during assisted thermal condensation. This disruption leads to the partial decomposition of the heptazine ring structure, resulting in the formation of C≡N functionalities on the CN surface, which are enriched with hydroxyl groups and undergo cyano modification. The formation of heterojunctions between CN and ZnO, which facilitate charge transfer along an immobilization pathway, accelerated charge transfer processes and improved reactant adsorption as well as electron utilization efficiency. The resulting catalyst was employed for the room temperature, atmospheric pressure, and solvent-free photocatalytic selective oxidation of cumene (CM), achieving a cumene conversion rate of 28.7% and a remarkable selectivity of 92.0% toward the desired product, cumene hydroperoxide (CHP). Furthermore, this CHP induced oxidative reactions, as demonstrated by the successful oxidation of benzylamine to imine and the oxidation of sulfide to sulfoxide, both yielding high product yields. Additionally, the utilization of a continuous-flow device significantly reduces the reaction time required for these oxidation processes. This work not only introduces an innovative approach to environmentally friendly, sustainable, clean, and efficient PHI synthesis but also underscores the promising potential and advantages of carbon nitride-based photocatalysts in the realm of sustainable and green organic transformations.
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BACKGROUND: To evaluate the safety and efficacy of endovascular denervation (EDN) as an adjunct to percutaneous vascular intervention (PVI) for peripheral artery disease (PAD). METHODS: From August 2019 to April 2021, 38 eligible patients with PAD enrolled in this study were randomly and equally assigned into 2 groups: the PVI group and the PVI + EDN group treated with EDN at the iliac and femoral arteries before PVI. The primary endpoint was the improvement in the ankle brachial index at 6 months after the procedure. The secondary endpoints were transcutaneous oxygen pressure (TcPO2), Rutherford category, numerical rating scale score, and safety. RESULTS: The technical success rates of PVI and EDN were 100%, and no device-related or procedure-related major adverse events occurred in either group. Compared with PVI alone, PVI + EDN demonstrated a significant improvement in limb hemodynamics at 6 months (Δ ankle brachial index 0.44 ± 0.31 vs. 0.24 ± 0.15, P = 0.018). Microcirculatory perfusion of PAD was significantly better at 6 months in the PVI + EDN group (ΔTcPO2, 15.68 ± 16.72 vs. 4.95 ± 13.43, P = 0.036). The Rutherford category was significantly improved in the PVI + EDN group in comparison with the PVI group at the 3-month follow-up (100.00% vs. 68.42%, P = 0.02). The decrease in the numerical rating scale score in the PVI + EDN group was greater than that in the PVI group at 1 week following the procedure (3 [2-5] vs. 4 [4-6], P = 0.022). CONCLUSIONS: In this single-center pilot analysis of a heterogeneous cohort of patients with PAD, PVI with EDN demonstrated a significant improvement in limb ischemia at 6 months compared with PVI alone.
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Procedimientos Endovasculares , Enfermedad Arterial Periférica , Humanos , Microcirculación , Resultado del Tratamiento , Enfermedad Arterial Periférica/diagnóstico por imagen , Enfermedad Arterial Periférica/cirugía , Isquemia/diagnóstico por imagen , Isquemia/cirugía , Desnervación , Procedimientos Endovasculares/efectos adversos , Procedimientos Endovasculares/métodos , Factores de RiesgoRESUMEN
Growth factor receptors rank among the most important oncogenic pathways, but pharmacologic inhibitors often demonstrate limited benefit as monotherapy. Here, we show that epidermal growth factor receptor (EGFR) signaling repressed N6-methyladenosine (m6A) levels in glioblastoma stem cells (GSCs), whereas genetic or pharmacologic EGFR targeting elevated m6A levels. Activated EGFR induced non-receptor tyrosine kinase SRC to phosphorylate the m6A demethylase, AlkB homolog 5 (ALKBH5), thereby inhibiting chromosomal maintenance 1 (CRM1)-mediated nuclear export of ALKBH5 to permit sustained mRNA m6A demethylation in the nucleus. ALKBH5 critically regulated ferroptosis through m6A modulation and YTH N6-methyladenosine RNA binding protein (YTHDF2)-mediated decay of the glutamate-cysteine ligase modifier subunit (GCLM). Pharmacologic targeting of ALKBH5 augmented the anti-tumor efficacy of EGFR and GCLM inhibitors, supporting an EGFR-ALKBH5-GCLM oncogenic axis. Collectively, EGFR reprograms the epitranscriptomic landscape through nuclear retention of the ALKBH5 demethylase to protect against ferroptosis, offering therapeutic paradigms for the treatment of lethal cancers.
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Desmetilasa de ARN, Homólogo 5 de AlkB , Receptores ErbB , Ferroptosis , Glioblastoma , Humanos , Adenosina/metabolismo , Desmetilasa de ARN, Homólogo 5 de AlkB/genética , Desmetilasa de ARN, Homólogo 5 de AlkB/metabolismo , Receptores ErbB/genética , Ferroptosis/genética , Glioblastoma/tratamiento farmacológico , Glioblastoma/genética , ARN Mensajero/genéticaRESUMEN
This paper aims at analyzing the characteristics of cardiopulmonary functions in the patients with ankylosing spondylitis (AS), and exploring the influence of global kyphosis (GK) on cardiopulmonary functions. Clinical data of 46 patients with AS and kyphosis, who had been admitted in our hospital from October 2021 to October 2022, were analyzed retrospectively. According to the to global kyphosis (GK) angle, 23 subjects were divided into Severe Group (GKâ >â 95°), and 23 subjects were divided into in the Moderate Group (80°â ≤â GKâ ≤â 95°). Cardiac structure and cardiopulmonary function parameters were compared between both groups, and the influences of GK Angle on other parameters were analyzed by Pearson or Spearman correlation analysis. The cardiac structure and function measurements in both groups were within the normal range. The pulmonary functions of both groups decreased to different extents. Correlation analysis showed that GK Angle was significantly negatively correlated with the left atrioventricular size (LAD, LVDD, LVSD) and diastolic function parameters (E/A, e'/a') in the patients with AS (Pâ <â .05); GK Angle was negatively correlated with restrictive ventilation parameters in the patients with AS (Pâ <â .05). The GK Angle of the patients with AS affects the cardiac structure and diastolic function. The larger the GK Angle is, the smaller the left and right at ventricle diameters are. In addition, GK Angle also affects the left ventricular diastolic function. GK Angle is related to the degree of pulmonary function impairment, and the larger the GK Angle is, the worse the pulmonary function it will be.
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Cifosis , Espondilitis Anquilosante , Humanos , Espondilitis Anquilosante/complicaciones , Estudios Retrospectivos , Cifosis/etiología , Pulmón , Corazón , Vértebras Lumbares , Vértebras TorácicasRESUMEN
BACKGROUND: Cognitive impairment is the most common clinical manifestation of ischemic leukoaraiosis (ILA), but the underlying neurobiological pathways have not been well elucidated. Recently, it was thought that ILA is a "disconnection syndrome". Disorganized brain connectome were considered the key neuropathology underlying cognitive deficits in ILA patients. OBJECTIVE: We aimed to detect the disruption of network hubs in ILA patients using a new analytical method called voxel-based eigenvector centrality (EC) mapping. METHODS: Subjects with moderate to severe white matters hyperintensities (Fazekas score ≥3) and healthy controls (HCs) (Fazekas scoreâ=â0) were included in the study. The resting-state functional magnetic resonance imaging and the EC mapping approach were performed to explore the alteration of whole-brain network connectivity in ILA patients. RESULTS: Relative to the HCs, the ILA patients exhibited poorer cognitive performance in episodic memory, information processing speed, and executive function (all psâ<â0.0125). Additionally, compared with HCs, the ILA patients had lower functional connectivity (i.e., EC values) in the medial parts of default-mode network (i.e., bilateral posterior cingulate gyrus and ventral medial prefrontal cortex [vMPFC]). Intriguingly, the functional connectivity strength at the right vMPFC was positively correlated with executive function deficit in the ILA patients. CONCLUSION: The findings suggested disorganization of the hierarchy of the default-mode regions within the whole-brain network in patients with ILA and advanced our understanding of the neurobiological mechanism underlying executive function deficit in ILA.
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Conectoma , Leucoaraiosis , Humanos , Función Ejecutiva , Leucoaraiosis/diagnóstico por imagen , Leucoaraiosis/patología , Imagen por Resonancia Magnética/métodos , Encéfalo/patología , Mapeo Encefálico , Conectoma/métodosRESUMEN
BACKGROUND: To evaluate the safety and efficacy of placing bare self-expanding metal stent (SEMS) for treating isolated superior mesenteric artery dissection (ISMAD). METHOD: Patients with ISMAD who received bare SEMS from January 2014 to December 2021 at the authors' center were included. Baseline characteristics, clinical manifestation, radiological findings, and treatment outcomes, including symptom relief and SMA remodeling, were analyzed. RESULT: A total of 26 patients were included in this study. Among the patients, 25 were admitted due to persistent abdominal pain, and 1 was admitted based on computed tomography angiography (CTA) during physical examination. According to CTA scan, the percentage of stenosis was 91% (53.8-100%), and the length of dissection was 100.2 ± 8.4 mm. All patients received bare SEMS placement. The median time to symptom relief was 1 day (interquartile range, 1 3 days). The the median follow-up time of CTA was 6.8 months (range, 2-85 months), with an average of 16.2 months. Complete remodeling of the superior mesenteric artery (SMA) was recorded in 24 patients. The median time to remodeling was 3 months with an average of 4.7 months. Survival analysis indicated no significance difference in remodeling time between different ISMAD types based on Yun classification (P = 0.888) or between acute and nonacute disease (P = 0.423). Incomplete remodeling was noted in 2 patients. Distal stent occlusion without SMA-related symptoms was seen in 1 patient. Proximal stent stenosis occurred in 1 patient, and restenting was performed. The median follow-up time by telephone was 20.8 (4-91.5) months, and no intestinal ischemic symptoms were observed in any patient. CONCLUSIONS: Bare SEMS placement can effectively relieve SMA-related symptoms in a short time and promote dissection remodeling in ISMAD. Time from symptom onset and classification of ISMAD seem not to have effects on SMA remodeling after bare SEMS placement.
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Disección , Arteria Mesentérica Superior , Humanos , Constricción Patológica , Arteria Mesentérica Superior/diagnóstico por imagen , Resultado del Tratamiento , StentsRESUMEN
PURPOSE: To analyze the risk factors for access-related adverse events (AEs) of the preclose technique in thoracic endovascular aortic repair (TEVAR). MATERIALS AND METHODS: Ninety-one patients with Stanford type B aortic dissection who underwent the preclose technique in TEVAR between January 2013 and December 2021 were included. According to the occurrence of access-related AEs, the patients were divided into 2 groups: those with AE and those without AE. Age, sex, combined diseases, body mass index, skin depth, femoral artery diameter, access calcification, iliofemoral artery tortuosity, and sheath size were recorded for risk factor analysis. The sheath-to-femoral artery ratio (SFAR), the ratio of the femoral artery inner diameter (in millimeters) to the sheath's outer diameter (in millimeters), was also included in the analysis. RESULTS: SFAR was identified as an independent risk factor for AEs using multivariable logistic analysis (odds ratio, 251.748; 95% CI, 7.004-9,048.534; P = .002). The cutoff value of SFAR was 0.85 and was related to a higher incidence of access-related AEs (5.2% vs 33.3%, P = .001), especially to a higher stenosis rate (0.0% vs 21.2%, P = .001). CONCLUSIONS: SFAR is an independent risk factor for access-related AEs of preclose in TEVAR with a cutoff value of 0.85. SFAR could be a new criterion for preoperative access evaluation in high-risk patients that may allow the detection and treatment of access-related AEs at the early stage.
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Aneurisma de la Aorta Torácica , Disección Aórtica , Implantación de Prótesis Vascular , Procedimientos Endovasculares , Humanos , Reparación Endovascular de Aneurismas , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Factores de Riesgo , Disección Aórtica/diagnóstico por imagen , Disección Aórtica/cirugía , Procedimientos Endovasculares/efectos adversos , Procedimientos Endovasculares/métodos , Estudios Retrospectivos , Aneurisma de la Aorta Torácica/diagnóstico por imagen , Aneurisma de la Aorta Torácica/cirugía , Aneurisma de la Aorta Torácica/etiología , Implantación de Prótesis Vascular/efectos adversos , Implantación de Prótesis Vascular/métodosRESUMEN
The molecular landscape and the intratumor heterogeneity (ITH) architecture of gastric linitis plastica (LP) are poorly understood. We performed whole-exome sequencing (WES) and T-cell receptor (TCR) sequencing on 40 tumor regions from four LP patients. The landscape and ITH at the genomic and immunological levels in LP tumors were compared with multiple cancers that have previously been reported. The lymphocyte infiltration was further assessed by immunohistochemistry (IHC) in LP tumors. In total, we identified 6339 non-silent mutations from multi-samples, with a median tumor mutation burden (TMB) of 3.30 mutations per Mb, comparable to gastric adenocarcinoma from the Cancer Genome Atlas (TCGA) cohort (P = 0.53). An extremely high level of genomic ITH was observed, with only 12.42%, 5.37%, 5.35%, and 30.67% of mutations detectable across 10 regions within the same tumors of each patient, respectively. TCR sequencing revealed that TCR clonality was substantially lower in LP than in multi-cancers. IHC using antibodies against CD4, CD8, and PD-L1 demonstrated scant T-cell infiltration in the four LP tumors. Furthermore, profound TCR ITH was observed in all LP tumors, with no T-cell clones shared across tumor regions in any of the patients, while over 94% of T-cell clones were restricted to individual tumor regions. The Morisita overlap index (MOI) ranged from 0.21 to 0.66 among multi-regions within the same tumors, significantly lower than that of lung cancer (P = 0.002). Our results show that LP harbored extremely high genomic and TCR ITH and suppressed T-cell infiltration, suggesting a potential contribution to the frequent recurrence and poor therapeutic response of this adenocarcinoma.
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Linitis Plástica , Neoplasias Gástricas , Humanos , Linitis Plástica/genética , Linitis Plástica/inmunología , Linitis Plástica/patología , Neoplasias Gástricas/genética , Neoplasias Gástricas/inmunología , Neoplasias Gástricas/patología , Secuenciación del Exoma , Heterogeneidad Genética , Genes Codificadores de los Receptores de Linfocitos T , Microambiente Tumoral , MutaciónRESUMEN
A Pd-catalyzed enantioselective three-component reaction of N-sulfonylhydrazones, aryl bromides, and silylboronic esters is developed, enabling the synthesis of chiral gem-diarylmethine silanes in high enantioselectivity with the use of a newly identified Ming-Phos. Compared with N-tosyl, the more easily decomposed N-mesitylsulfonyl is more suitable as the masking group of electron-rich hydrazone to improve the reaction efficiency. The reaction features a broad scope concerning both coupling partners, high enantioselectivity, and mild reaction conditions. The ready access to enantiomers and utility of this catalytic method are also presented.
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Paladio , Silanos , Catálisis , Ésteres , EstereoisomerismoRESUMEN
Segmental testicular infarction is a rare clinical condition most often seen as acute unilateral scrotal pain. Segmental testicular infarction should be suspected in patients with scrotal pain; when an ultrasound shows hypoechoic or mixed echogenic lesions within the testicular parenchyma; contrast-enhanced ultrasound shows a little or no contrast filling, along with negative multiple tumor markers. This report presents a 60-year-old male who presented with sudden onset of left testicular pain with no apparent cause. Emergency Doppler ultrasound, contrast-enhanced ultrasound, and laboratory tests showed findings characteristic of Segmental testicular infarction. The patient the final diagnosis was based on a combination of clinical findings (regression or cessation of symptoms, no tumor marker abnormalities, no palpable testicular mass) and ultrasound evidence of improvement (size reduction or shape change from oval to wedge) during a follow-up period of at least 3 months.
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Two-dimensional high-throughput data have become increasingly common in functional genomics studies, which raises new challenges in data analysis. Here, we introduce a new statistic called Zeta, initially developed to identify global splicing regulators from a two-dimensional RNAi screen, a high-throughput screen coupled with high-throughput functional readouts, and ZetaSuite, a software package to facilitate general application of the Zeta statistics. We compare our approach with existing methods using multiple benchmarked datasets and then demonstrate the broad utility of ZetaSuite in processing public data from large-scale cancer dependency screens and single-cell transcriptomics studies to elucidate novel biological insights.
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Ensayos Analíticos de Alto Rendimiento , Transcriptoma , Genómica/métodos , Ensayos Analíticos de Alto Rendimiento/métodos , Interferencia de ARN , Análisis de la Célula Individual , Programas InformáticosRESUMEN
Oxidative coupling of methane (OCM) catalyzed by MnOx -Na2 WO4 -based catalysts has great industrial potential to convert CH4 directly to C2-3 products, but the high light-off temperature is a big challenge to OCM commercialization. The reaction mechanism studies disclosed that O2 /CH4 -activation relevant "Mn2+ âMn3+ " redox cycle is tightly linked with the catalyst light-off. One concept is thus put forward that the OCM light-off temperature could be lowered once a "Mn2+ âMn3+ " redox cycle was established to be triggered at low temperature over MnOx -Na2 WO4 -based catalysts. The relevant studies in recent years are reviewed, showing that the establishment of low-temperature light-off "Mn2+ âMn3+ " redox cycle over the MnOx -Na2 WO4 -based catalysts indeed works effectively toward a low-temperature light-off OCM process. Moreover, three perspectives for the OCM industrialization are discussed based on this concept, including monolithic catalyst, fluidized-bed method and chemical-looping process.
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Catalytic reduction of nitroaromatic compounds using low-cost non-precious metal containing catalyst remains an essential topic in wastewater treatment. Herein, copper hexacyanoferrate nanospheres decorated copper foams (CF) were prepared by a facile method, and it was used as structured catalysts for the reduction of p-nitrophenol (p-NP) and azo dyes. The catalyst obtained by calcination at 200 °C shows the highest catalytic activity, with an almost complete reduction of p-NP within 3 min with a rate of 2.057 min-1 at room temperature, and it exhibited excellent reusability in successive 6 cycles. The effects of temperature, initial concentration, pH, and flow rate on p-NP reduction were investigated. Moreover, the mechanistic investigation revealed that fast electron transfer ability and enhanced adsorption for p-NP contributed to its enhanced catalytic performances. This work put forward an efficient approach for the construction of structured catalysts with enhanced performance in catalytic reduction applications.