Large-scale CO_(2)emissions have exacerbated the greenhouse effect,reinforcing the critical need for efficient CO_(2)mitigation methods.Plasma-catalytic technology enables CO_(2)conversion under mild conditions,especi...Large-scale CO_(2)emissions have exacerbated the greenhouse effect,reinforcing the critical need for efficient CO_(2)mitigation methods.Plasma-catalytic technology enables CO_(2)conversion under mild conditions,especially for CO_(2)methanation(the Sabatier reaction),which has attracted significant attention due to its economic benefits and the potential for safe energy transportation via existing natural gas pipelines.The development of high-performance CO_(2)methanation catalysts remains an ongoing and long-term objective,and there is a lack of adequate in-situ characterization techniques to investigate the mechanisms.This study focuses on the Ni/La_(2)O_(3)(LN)catalyst and introduces two CO_(2)activation strategies through F and Na modifications:the Ni-Ov-Ni site activation with electron transfer from Ni0 under low-power conditions and basic site activation under high-power conditions.The LN-NaF catalysts enhance CO_(2)methanation activity across the entire power range compared to LN,achieving a CO_(2)conversion of 86.3%and CH4 selectivity of 99.4%.Additionally,LN-F(h)reaches a CH4 yield 4.15 times higher than that of LN at low power.Furthermore,in-situ diffuse reflectance infrared Fourier transform(DRIFT)spectroscopy with a self-made reactor are performed under plasma-catalytic conditions to reveal the CO_(2)adsorption and conversion mechanisms,indicating that different dopants(F,Na,and NaF)exhibit promoting effects on different intermediates,resulting in variations in CO_(2)methanation activity.This study provides valuable insights for improving catalyst performance and a thorough comprehension of mechanisms in CO_(2)methanation.展开更多
Objectives The discovery of novel molecular targets to enhance the osteogenesis of human bone marrow-derived mesenchymal stem cells(H-BMSCs)represents a promising strategy for preventing and treating osteoporosis.Thus...Objectives The discovery of novel molecular targets to enhance the osteogenesis of human bone marrow-derived mesenchymal stem cells(H-BMSCs)represents a promising strategy for preventing and treating osteoporosis.Thus,the primary objective of this study is to elucidate the mechanisms by which long non-coding RNA FOXD2-AS1(lncRNA FOXD2-AS1)regulates early osteogenic differentiation in H-BMSCs,thereby identifying potential therapeutic targets.Methods Lentivirus-mediated vectors were constructed to either overexpress or silence FOXD2-AS1 in H-BMSCs.The effects of FOXD2-AS1 on osteogenesis were subsequently assessed by analyzing osteogenic marker expression and alkaline phosphatase(ALP)staining.To clarify the role of the Janus kinase 2/signal transducer and activator of transcription 3(JAK2/STAT3)pathway in this process,AG490 inhibitor(a JAK2/STAT3 pathway inhibitor)and knockdown of STAT3 were used to investigate the mechanisms of FOXD2-AS1.Results FOXD2-AS1 overexpression increased ALP activity and osteogenic marker expression,while its knockdown had the opposite effects.From a mechanistic perspective,FOXD2-AS1 overexpression promoted JAK2 and STAT3 phosphorylation,whereas its suppression attenuated their activation.Also,the osteogenic increase induced by FOXD2-AS1 overexpression was reversed by AG490 treatment or STAT3 silencing,indicating that the pathway plays a role in this process.Conclusion FOXD2-AS1 was identified as a novel genetic switch driving osteogenic commitment via JAK2/STAT3 activation,revealing a new regulatory mechanism and a potential therapeutic target for osteoporosis.展开更多
The technology for green and macro-conversion of solid waste biomass to prepare high-quality activated carbon demands urgent development.This study proposes a technique for synthesizing carbon adsorbents using trace K...The technology for green and macro-conversion of solid waste biomass to prepare high-quality activated carbon demands urgent development.This study proposes a technique for synthesizing carbon adsorbents using trace KOH-catalyzed CO_(2) activation.Comprehensive investigations were conducted on three aspects:physicochemical structure evolution of biochar,mechanistic understanding of trace KOH-facilitated CO_(2) activation processes,and application characteristics for CO_(2) adsorption.Results demonstrate that biochar activated by trace KOH(<10%)and CO_(2) achieves comparable specific surface area(1244.09 m^(2)/g)to that obtained with 100%KOH activation(1425.10 m^(2)/g).The pore structure characteristics(specific surface area and pore volume)are governed by CO and CH4 generated through K-salt catalyzed reactions between CO_(2) and biochar.The optimal CO_(2) adsorption capacities of KBC adsorbent reached 4.70 mmol/g(0℃)and 7.25 mmol/g(25℃),representing the maximum values among comparable carbon adsorbents.The 5%KBC-CO_(2) sample exhibited CO_(2) adsorption capacities of 3.19 and 5.01 mmol/g under respective conditions,attaining current average performance levels.Notably,CO_(2)/N_(2) selectivity(85∶15,volume ratio)reached 64.71 at 0.02 bar with robust cycling stability.Molecular dynamics simulations revealed that oxygen-containing functional groups accelerate CO_(2) adsorption kinetics and enhance micropore storage capacity.This technical route offers simplicity,environmental compatibility,and scalability,providing critical references for large-scale preparation of high-quality carbon materials.展开更多
Electrocatalytic CO_(2)reduction reaction(CO_(2)RR)to ethylene(C_(2)H_(4))represents a promising approach to reducing CO_(2)emissions and producing high-value chemicals.The ethylene productivity is always limited by t...Electrocatalytic CO_(2)reduction reaction(CO_(2)RR)to ethylene(C_(2)H_(4))represents a promising approach to reducing CO_(2)emissions and producing high-value chemicals.The ethylene productivity is always limited by the slow reaction kinetics and the high-performance catalysts are significantly desired.Many efforts have been made to develop a catalyst to activate CO_(2)molecules.However,as another reactant,H2O activation does not receive the attention it deserves.In particular,slow H2O dissociation kinetics limit the rate of proton supply,severely impairing the production of C_(2)H_(4).Here,we designed a MgO-modified CuO catalyst(MgO/CuO),which can promote H2O dissociation and enhance CO_(2)adsorption at the same time to realize the efficient ethylene production.The optimal catalyst exhibits a Faraday efficiency for C_(2)H_(4)reached 54.4%at−1.4 V vs.RHE in an H-cell,which is 1.4 times that of pure CuO(37.9%),and it was further enhanced to a 56.7%in a flow cell,with a high current density of up to 535.9 mA cm−2 at−1.0 V vs.RHE.Experimental and theoretical calculations show that MgO/CuO plays a bifunctional role in the CO_(2)RR,which facilitates the adsorption and activation of CO_(2)by CuO and simultaneously accelerates H2O dissociation by MgO doping.The in situ XRD experiments demonstrate that the introduction of MgO protects CuO active phase to avoid overreduction and preserves the active centers for CO_(2)RR.In combination with in situ FTIR and DFT calculations,the protonation process from*CO to*COH and asymmetric C–C coupling step are promoted by the enhanced water activation and proton coupling on MgO/CuO.This work provides new insights into the CO_(2)and H_(2)O coactivation mechanism in CO_(2)RR and a potential universal strategy to design ethylene production electrocatalysts.展开更多
Photocatalytic CO_(2)reduction is a promising route toward carbon neutrality,yet its practical application is hindered by the high activation energy barrier of v,rapid recombination of photo-generated electrons,and po...Photocatalytic CO_(2)reduction is a promising route toward carbon neutrality,yet its practical application is hindered by the high activation energy barrier of v,rapid recombination of photo-generated electrons,and poor product selectivity of traditional catalysts.Frustrated Lewis pairs(FLPs),which feature spatially separated Lewis acid and base sites,have recently emerged as a novel strategy to overcome these limitations.This review systematically examines the progress in FLPs-based photocatalytic systems.We focus on the construction stra-tegies for FLPs active sites,the optimization of charge carrier dynamics,and the synergistic electron transfer mechanisms with photoactive components.Central theme is the elucidation of microscopic mechanisms gov-erning CO_(2)activation,key intermediate conversion,and the efficient utilization of photogenerated electrons.By synthesizing current knowledge and outlining future prospects,this review aims to provide a theoretical framework that guides the rational design of highly active and selective catalysts for solar-driven CO_(2)reduction.展开更多
It has been challenging for Fe(Ⅲ)regeneration in Fe-based photocatalysts for continuous peroxydisulfate(PDS)activation due to the lower ability to reduce Fe(Ⅲ).In this work,Fe-doped ultrathin VO_(2)(Fe-VO_(2))nanobe...It has been challenging for Fe(Ⅲ)regeneration in Fe-based photocatalysts for continuous peroxydisulfate(PDS)activation due to the lower ability to reduce Fe(Ⅲ).In this work,Fe-doped ultrathin VO_(2)(Fe-VO_(2))nanobelts were synthesized for purifying metronidazole(MNZ)via PDS activation.As an efficient Fentonlike catalyst for PDS activation,2 wt%Fe-doped VO_(2)can remove 98%of MNZ within 40 min and exhibits impressive recyclability.The synergistic effect of Fe-VO_(2)and Fe(Ⅲ)activated PDS boosted the photocatalytic performance.Moreover,SO_(4)•^(−),h+,O_(2)•^(−),^(1)O_(2),and•OH were the main reactive radicals.The effects of initial MNZ concentration,Fe-VO_(2),PDS dosage,and various anions/cations on MNZ removal by the Fe-VO_(2)/PDS/Vis system were studied.The intermediates of MNZ degradation and possible pathways were determined by density function theory(DFT)calculations and HPLC-MS.This study provided a sustainable technology using Fe-doped ultrathin VO_(2)nanobelts for photocatalytic PDS activation and decontamination of pharmaceutical wastewater.展开更多
The influence of electronic structure on the performance of catalysts for peroxymonosulfate(PMS)activation remains ambiguous.In this study,the 3d electron configuration of Fe(Ⅲ)in AgFeO_(2) was atomically regulated u...The influence of electronic structure on the performance of catalysts for peroxymonosulfate(PMS)activation remains ambiguous.In this study,the 3d electron configuration of Fe(Ⅲ)in AgFeO_(2) was atomically regulated using cobalt doping.The amount of PMS adsorbed and the catalytic performance were positively correlated with the total effective magnetic moment and the ratios of high-spin Fe(Ⅲ)and eg filling within the catalysts.These 3d electron regulations favor PMS adsorption and electron transfer owing to the lower PMS adsorption energy,increased electronic states near the Fermi level,and reduced dz^(2) orbital occupancy.Benefiting from fine tailoring of the electron configuration,the AgFe_(0.80)Co_(0.20)O_(2) catalyst exhibited outstanding catalytic PMS activation and favorable application potential,achieving efficient pharmaceutical wastewater treatment and more than 80%ofloxacin removal after 72 h of continuous-flow operation.Notably,this study offers a comprehensive understanding for the influence mechanism of electronic structure regulation on PMS activation,providing design guidance for the development of efficient heterogeneous Fenton-like catalytic systems.展开更多
Oxygen activation leading to the generation of reactive oxygen species(ROS)is essential for photocatalytic environmental remediation.The limited efficiency of O_(2)adsorption and reductive activation significantly lim...Oxygen activation leading to the generation of reactive oxygen species(ROS)is essential for photocatalytic environmental remediation.The limited efficiency of O_(2)adsorption and reductive activation significantly limits the production of ROS when employing C_(3)N_(4)for the degradation of emerging pollutants.Doping with metal single atoms may lead to unsatisfactory efficiency,due to the recombination of photogenerated electron-hole pairs.Here,Mn and S single atoms were introduced into C_(3)N_(4),resulting in the excellent photocatalytic performances.Mn/S-C_(3)N_(4)achieved 100%removal of bisphenol A,with a rate constant 11 times that of pristine C_(3)N_(4).According to the experimental results and theoretical simulations,Satoms restrict holes,facilitating the photo-generated carriers’separation.Single-atom Mn acts as the O_(2)adsorption site,enhancing the adsorption and activation of O_(2),resulting the generation of ROS.This study presents a novel approach for developing highly effective photocatalysts that follows a new mechanism to eliminate organic pollutants from water.展开更多
Volatile Organic Compounds(VOCs)are highly harmful to human beings and other organisms,and thus the elimination of VOCs is extremely urgent.Here,La-Si co-doped TiO_(2)microsphere photocatalysts,which were prepared by ...Volatile Organic Compounds(VOCs)are highly harmful to human beings and other organisms,and thus the elimination of VOCs is extremely urgent.Here,La-Si co-doped TiO_(2)microsphere photocatalysts,which were prepared by a hydrothermal method,exhibited high photocatalytic activity in the decomposition of formaldehyde compared with TiO_(2).The improved activity can be attributed to the promoted separation efficiency and density of the charge carriers,as verified by the electrochemical results in combination with density functional theory calculations.In addition,the Si dopant changed the microstructure and surface acidity,while the addition of La promoted the separation efficiency of charge carriers.More interestingly,it was found that singlet oxygen was the key species in the activation of molecular dioxygen,and it played a pivotal role in the photocatalytic decomposition of formaldehyde.This work provides a novel strategy for the selective activation of dioxygen for use in the decomposition of formaldehyde.展开更多
A meticulous design of the local environment at the interface between active species and the support,aimed at optimizing the adsorption of H_(2)O molecules and BH_(4)^(-)anion,offers an ideal strategy for enhancing hy...A meticulous design of the local environment at the interface between active species and the support,aimed at optimizing the adsorption of H_(2)O molecules and BH_(4)^(-)anion,offers an ideal strategy for enhancing hydrogen generation via Na BH4hydrolysis through dual activation pathways.Theoretical predictions based on d-band center analysis and electron transfer calculations suggest that introducing-OH functional groups induce charge redistribution,enhancing charge concentration on alk-Ti_(3)C_(2)and facilitating the adsorption and activation of dual active species,H2O molecules and BH4-anion.Inspired by these predictions,the optimized alk-Ti_(3)C_(2)/Ru Oxcatalyst demonstrates the highest catalytic activity,achieving a hydrogen generation rate(HGR)of 9468 m L min^(-1)gcat.^(-1).Both experimental data and theoretical analyses confirm that the-OH functional groups promote charge enrichment on alk-Ti_(3)C_(2),optimizing the adsorption of H_(2)O molecules and BH_(4)^(-)anion,and reducing the dissociation energy barrier of the*OH–H-TS intermediate.This dual activation pathways mechanism lowers the activation energy for Na BH4hydrolysis,significantly enhancing the HGR performance.These findings,guided by theoretical insights,establish alk-Ti_(3)C_(2)/Ru Oxas an efficient catalyst for Na BH4hydrolysis and provide a strong foundation for future hydrogen generation catalyst designs.展开更多
AIM: To investigate the effect of herbal compound 861 (Cpd861) on the transforming growth factor-β1 (TGFβ1)/ activin receptor-like kinase 1 (ALK1, type Ⅰ receptor) signaling-pathway-related gene expression in the L...AIM: To investigate the effect of herbal compound 861 (Cpd861) on the transforming growth factor-β1 (TGFβ1)/ activin receptor-like kinase 1 (ALK1, type Ⅰ receptor) signaling-pathway-related gene expression in the LX-2 cell line, and the inhibitory mechanism of Cpd861 on the activation of LX-2 cells. METHODS: LX-2 cells were treated with TGFβ1 (5 ng/mL) Cpd861 (0.1 mg/mL), TGFβ1 (5 ng/mL) plus Cpd861 (5 ng/mL) for 24 h to investigate the effect of Cpd861 on the TGFβ1/ALK1 pathway. Real-time PCR was performed to examine the expression of α-SMA (α-smooth muscle actin), ALK1, Id1 (inhibitor of differentiation 1). Western blotting was carried out to measure the levels of α-SMA and phosphorylated Smad1, and immunocytochemical analysis for the expression of α-SMA. RESULTS: In LX-2 cells, TGFβ1/ALK1-pathway-related gene expression could be stimulated by TGFβ1, which led to excessive activation of the cells. Cpd861 decreased the activation of LX-2 cells by reducing the expression of α-SMA mRNA and protein expression. This effect was related to inhibition of the above TGFβ1/ALK1-pathway- related expression of genes such as Id1 and ALK1, and phosphorylation of Smad1 in LX-2 cells, even with TGFβ1 co-treatment for 24 h. CONCLUSION: Cpd861 can restrain the activation of LX-2 cells by inhibiting the TGFβ1/ALK1/Smad1 pathway.展开更多
AIM: To assess the usefulness of urinary trypsinogen-2 test strip, urinary trypsinogen activation peptide (TAP),and serum and urine concentrations of the activation peptide of carboxypeptidase B (CAPAP) in the diagnos...AIM: To assess the usefulness of urinary trypsinogen-2 test strip, urinary trypsinogen activation peptide (TAP),and serum and urine concentrations of the activation peptide of carboxypeptidase B (CAPAP) in the diagnosisof acute pancreatitis.METHODS: Patients with acute abdominal pain and hospitalized within 24 h after the onset of symptoms were prospectively studied. Urinary trypsinogen-2 was considered positive when a clear blue line was observed (detection limit 50 μg/L). Urinary TAP was measured using a quantitative solid-phase ELISA, and serum and urinary CAPAP by a radioimmunoassay method.RESULTS: Acute abdominal pain was due to acute pancreatitis in 50 patients and turned out to be extrapancreatic in origin in 22 patients. Patients with acute pancreatitis showed significantly higher median levels of serum and urinary CAPAP levels, as well as amylase and lipase than extrapancreatic controls. Median TAP levels were similar in both groups. The urinary trypsinogen-2 test strip was positive in 68% of patients with acute pancreatitis and 13.6% in extrapancreatic controls (P<0.01). Urinary CAPAP was the most reliable test for the diagnosis of acute pancreatitis (sensitivity 66.7%, specificity 95.5%, positive and negative predictive values 96.6% and 56.7%, respectively), with a 14.6 positive likelihood ratio for a cut-off value of 2.32 nmol/L.CONCLUSION: In patients with acute abdominal pain,hospitalized within 24 h of symptom onset, CAPAP in serum and urine was a reliable diagnostic marker of acute pancreatitis. Urinary trypsinogen-2 test strip showed a clinical value similar to amylase and lipase.Urinary TAP was not a useful screening test for the diagnosis of acute pancreatitis.展开更多
The CO2 adsorption data may show more than one section in the Dubinin-Radushkevich-Kaganer(DRK) plot if samples had been over-activated. Each section in the plot represents a range of pore size. The whole DRK plot pro...The CO2 adsorption data may show more than one section in the Dubinin-Radushkevich-Kaganer(DRK) plot if samples had been over-activated. Each section in the plot represents a range of pore size. The whole DRK plot provided information on the pore size distribution(PSD) of a sample, which may be used to monitor the effect of activation conditions in activation processes.展开更多
Indoleamine 2, 3-dioxygenase (IDO) is a rate-limiting enzyme for the tryptophan catabolism. In human and murine cells, IDO inhibits antigen-specific T cell proliferation in vitro and suppresses T cell responses to fet...Indoleamine 2, 3-dioxygenase (IDO) is a rate-limiting enzyme for the tryptophan catabolism. In human and murine cells, IDO inhibits antigen-specific T cell proliferation in vitro and suppresses T cell responses to fetal alloantigens during murine pregnancy. In mice, IDO expression is an inducible feature of specific subsets of dendritic cells (DCs), and is important for T cell regulatory properties. However, the effect of IDO and tryptophan deprivation on DC func- tions remains unknown. We report here that when tryptophan utilization was prevented by a pharmacological inhibitor of IDO, 1-methyl tryptophan (1MT), DC activation induced by pathogenic stimulus lipopolysaccharide (LPS) or inflam- matory cytokine TNF-α was inhibited both phenotypically and functionally. Such an effect was less remarkable when DC was stimulated by a physiological stimulus, CD40 ligand. Tryptophan deprivation during DC activation also regu- lated the expression of CCR5 and CXCR4, as well as DC responsiveness to chemokines. These results suggest that tryptophan usage in the microenvironment is essential for DC maturation, and may also play a role in the regulation of DC migratory behaviors.展开更多
基金supported by the National Natural Science Foundation of China(No.51878292).
文摘Large-scale CO_(2)emissions have exacerbated the greenhouse effect,reinforcing the critical need for efficient CO_(2)mitigation methods.Plasma-catalytic technology enables CO_(2)conversion under mild conditions,especially for CO_(2)methanation(the Sabatier reaction),which has attracted significant attention due to its economic benefits and the potential for safe energy transportation via existing natural gas pipelines.The development of high-performance CO_(2)methanation catalysts remains an ongoing and long-term objective,and there is a lack of adequate in-situ characterization techniques to investigate the mechanisms.This study focuses on the Ni/La_(2)O_(3)(LN)catalyst and introduces two CO_(2)activation strategies through F and Na modifications:the Ni-Ov-Ni site activation with electron transfer from Ni0 under low-power conditions and basic site activation under high-power conditions.The LN-NaF catalysts enhance CO_(2)methanation activity across the entire power range compared to LN,achieving a CO_(2)conversion of 86.3%and CH4 selectivity of 99.4%.Additionally,LN-F(h)reaches a CH4 yield 4.15 times higher than that of LN at low power.Furthermore,in-situ diffuse reflectance infrared Fourier transform(DRIFT)spectroscopy with a self-made reactor are performed under plasma-catalytic conditions to reveal the CO_(2)adsorption and conversion mechanisms,indicating that different dopants(F,Na,and NaF)exhibit promoting effects on different intermediates,resulting in variations in CO_(2)methanation activity.This study provides valuable insights for improving catalyst performance and a thorough comprehension of mechanisms in CO_(2)methanation.
基金supported by the Natural Science Foundation of Hubei Province of China(Grant No.2023AFB671)the National Natural Science Foundation of China(Grant Nos.82360177 and 82560182)+1 种基金the Key Project of Jiangxi Provincial Natural Science Foundation(Grant No.20224ACB206011)“Xuncheng Talents”Project in Jiujiang City,Jiangxi Province(Grant No.JJXC2023071).
文摘Objectives The discovery of novel molecular targets to enhance the osteogenesis of human bone marrow-derived mesenchymal stem cells(H-BMSCs)represents a promising strategy for preventing and treating osteoporosis.Thus,the primary objective of this study is to elucidate the mechanisms by which long non-coding RNA FOXD2-AS1(lncRNA FOXD2-AS1)regulates early osteogenic differentiation in H-BMSCs,thereby identifying potential therapeutic targets.Methods Lentivirus-mediated vectors were constructed to either overexpress or silence FOXD2-AS1 in H-BMSCs.The effects of FOXD2-AS1 on osteogenesis were subsequently assessed by analyzing osteogenic marker expression and alkaline phosphatase(ALP)staining.To clarify the role of the Janus kinase 2/signal transducer and activator of transcription 3(JAK2/STAT3)pathway in this process,AG490 inhibitor(a JAK2/STAT3 pathway inhibitor)and knockdown of STAT3 were used to investigate the mechanisms of FOXD2-AS1.Results FOXD2-AS1 overexpression increased ALP activity and osteogenic marker expression,while its knockdown had the opposite effects.From a mechanistic perspective,FOXD2-AS1 overexpression promoted JAK2 and STAT3 phosphorylation,whereas its suppression attenuated their activation.Also,the osteogenic increase induced by FOXD2-AS1 overexpression was reversed by AG490 treatment or STAT3 silencing,indicating that the pathway plays a role in this process.Conclusion FOXD2-AS1 was identified as a novel genetic switch driving osteogenic commitment via JAK2/STAT3 activation,revealing a new regulatory mechanism and a potential therapeutic target for osteoporosis.
基金supported by the National Natural Science Foundation of China(52376103,542B2081).
文摘The technology for green and macro-conversion of solid waste biomass to prepare high-quality activated carbon demands urgent development.This study proposes a technique for synthesizing carbon adsorbents using trace KOH-catalyzed CO_(2) activation.Comprehensive investigations were conducted on three aspects:physicochemical structure evolution of biochar,mechanistic understanding of trace KOH-facilitated CO_(2) activation processes,and application characteristics for CO_(2) adsorption.Results demonstrate that biochar activated by trace KOH(<10%)and CO_(2) achieves comparable specific surface area(1244.09 m^(2)/g)to that obtained with 100%KOH activation(1425.10 m^(2)/g).The pore structure characteristics(specific surface area and pore volume)are governed by CO and CH4 generated through K-salt catalyzed reactions between CO_(2) and biochar.The optimal CO_(2) adsorption capacities of KBC adsorbent reached 4.70 mmol/g(0℃)and 7.25 mmol/g(25℃),representing the maximum values among comparable carbon adsorbents.The 5%KBC-CO_(2) sample exhibited CO_(2) adsorption capacities of 3.19 and 5.01 mmol/g under respective conditions,attaining current average performance levels.Notably,CO_(2)/N_(2) selectivity(85∶15,volume ratio)reached 64.71 at 0.02 bar with robust cycling stability.Molecular dynamics simulations revealed that oxygen-containing functional groups accelerate CO_(2) adsorption kinetics and enhance micropore storage capacity.This technical route offers simplicity,environmental compatibility,and scalability,providing critical references for large-scale preparation of high-quality carbon materials.
基金supported by the National Natural Science Foundation of China(Grant No.U21B2099,U22A20425,and 22208377)Natural Science Foundation of Shandong Province(ZR2021QE062)Fundamental Research Funds for the Central Universities,Ocean University of China(grant number 202364004)。
文摘Electrocatalytic CO_(2)reduction reaction(CO_(2)RR)to ethylene(C_(2)H_(4))represents a promising approach to reducing CO_(2)emissions and producing high-value chemicals.The ethylene productivity is always limited by the slow reaction kinetics and the high-performance catalysts are significantly desired.Many efforts have been made to develop a catalyst to activate CO_(2)molecules.However,as another reactant,H2O activation does not receive the attention it deserves.In particular,slow H2O dissociation kinetics limit the rate of proton supply,severely impairing the production of C_(2)H_(4).Here,we designed a MgO-modified CuO catalyst(MgO/CuO),which can promote H2O dissociation and enhance CO_(2)adsorption at the same time to realize the efficient ethylene production.The optimal catalyst exhibits a Faraday efficiency for C_(2)H_(4)reached 54.4%at−1.4 V vs.RHE in an H-cell,which is 1.4 times that of pure CuO(37.9%),and it was further enhanced to a 56.7%in a flow cell,with a high current density of up to 535.9 mA cm−2 at−1.0 V vs.RHE.Experimental and theoretical calculations show that MgO/CuO plays a bifunctional role in the CO_(2)RR,which facilitates the adsorption and activation of CO_(2)by CuO and simultaneously accelerates H2O dissociation by MgO doping.The in situ XRD experiments demonstrate that the introduction of MgO protects CuO active phase to avoid overreduction and preserves the active centers for CO_(2)RR.In combination with in situ FTIR and DFT calculations,the protonation process from*CO to*COH and asymmetric C–C coupling step are promoted by the enhanced water activation and proton coupling on MgO/CuO.This work provides new insights into the CO_(2)and H_(2)O coactivation mechanism in CO_(2)RR and a potential universal strategy to design ethylene production electrocatalysts.
基金the National Natural Science Foundation of China(22278190)Qing Lan Project of Jiangsu Province(2023)+1 种基金Open Project of State Key Laboratory of Structural Chemistry(20230022)Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment.
文摘Photocatalytic CO_(2)reduction is a promising route toward carbon neutrality,yet its practical application is hindered by the high activation energy barrier of v,rapid recombination of photo-generated electrons,and poor product selectivity of traditional catalysts.Frustrated Lewis pairs(FLPs),which feature spatially separated Lewis acid and base sites,have recently emerged as a novel strategy to overcome these limitations.This review systematically examines the progress in FLPs-based photocatalytic systems.We focus on the construction stra-tegies for FLPs active sites,the optimization of charge carrier dynamics,and the synergistic electron transfer mechanisms with photoactive components.Central theme is the elucidation of microscopic mechanisms gov-erning CO_(2)activation,key intermediate conversion,and the efficient utilization of photogenerated electrons.By synthesizing current knowledge and outlining future prospects,this review aims to provide a theoretical framework that guides the rational design of highly active and selective catalysts for solar-driven CO_(2)reduction.
基金the financial supports from the National Key Research and Development Program of China(Nos.2021YFB3500600,2021YFB3500605,2022YFB3504100)Key R&D Program of Jiangsu Province(No.BE2022142)+6 种基金Ministry of Education Chunhui plan international cooperation project(No.202200554)National Natural Science Foundation of China(No.grant 22208170)Natural Science Foundation of Inner Mongolia(No.2021BS02016)Jiangsu International Cooperation Project(No.BZ2021018)Nanjing Science and Technology Top Experts Gathering Plan,and Open Foundation of State Environmental Protection Key Laboratory of Soil Environmental Management and Pollution Control(No.SEMPC2023004)Cooperation Foundation for the Chunhui Plan Program of Ministry of Education of China(No.202200554)Open Project Program of Key Laboratory of Opticelectric Sensing and Analytical Chemistry for Life Science(No.M2024-7),MOE。
文摘It has been challenging for Fe(Ⅲ)regeneration in Fe-based photocatalysts for continuous peroxydisulfate(PDS)activation due to the lower ability to reduce Fe(Ⅲ).In this work,Fe-doped ultrathin VO_(2)(Fe-VO_(2))nanobelts were synthesized for purifying metronidazole(MNZ)via PDS activation.As an efficient Fentonlike catalyst for PDS activation,2 wt%Fe-doped VO_(2)can remove 98%of MNZ within 40 min and exhibits impressive recyclability.The synergistic effect of Fe-VO_(2)and Fe(Ⅲ)activated PDS boosted the photocatalytic performance.Moreover,SO_(4)•^(−),h+,O_(2)•^(−),^(1)O_(2),and•OH were the main reactive radicals.The effects of initial MNZ concentration,Fe-VO_(2),PDS dosage,and various anions/cations on MNZ removal by the Fe-VO_(2)/PDS/Vis system were studied.The intermediates of MNZ degradation and possible pathways were determined by density function theory(DFT)calculations and HPLC-MS.This study provided a sustainable technology using Fe-doped ultrathin VO_(2)nanobelts for photocatalytic PDS activation and decontamination of pharmaceutical wastewater.
文摘The influence of electronic structure on the performance of catalysts for peroxymonosulfate(PMS)activation remains ambiguous.In this study,the 3d electron configuration of Fe(Ⅲ)in AgFeO_(2) was atomically regulated using cobalt doping.The amount of PMS adsorbed and the catalytic performance were positively correlated with the total effective magnetic moment and the ratios of high-spin Fe(Ⅲ)and eg filling within the catalysts.These 3d electron regulations favor PMS adsorption and electron transfer owing to the lower PMS adsorption energy,increased electronic states near the Fermi level,and reduced dz^(2) orbital occupancy.Benefiting from fine tailoring of the electron configuration,the AgFe_(0.80)Co_(0.20)O_(2) catalyst exhibited outstanding catalytic PMS activation and favorable application potential,achieving efficient pharmaceutical wastewater treatment and more than 80%ofloxacin removal after 72 h of continuous-flow operation.Notably,this study offers a comprehensive understanding for the influence mechanism of electronic structure regulation on PMS activation,providing design guidance for the development of efficient heterogeneous Fenton-like catalytic systems.
基金supported by the Key Research&Developmental Programof Shandong Province(No.2021CXGC011202)the National Natural Science Foundation of China(Nos.22276110 and 22106088)the Fundamental Research Funds of Shandong University(No.zy202102).
文摘Oxygen activation leading to the generation of reactive oxygen species(ROS)is essential for photocatalytic environmental remediation.The limited efficiency of O_(2)adsorption and reductive activation significantly limits the production of ROS when employing C_(3)N_(4)for the degradation of emerging pollutants.Doping with metal single atoms may lead to unsatisfactory efficiency,due to the recombination of photogenerated electron-hole pairs.Here,Mn and S single atoms were introduced into C_(3)N_(4),resulting in the excellent photocatalytic performances.Mn/S-C_(3)N_(4)achieved 100%removal of bisphenol A,with a rate constant 11 times that of pristine C_(3)N_(4).According to the experimental results and theoretical simulations,Satoms restrict holes,facilitating the photo-generated carriers’separation.Single-atom Mn acts as the O_(2)adsorption site,enhancing the adsorption and activation of O_(2),resulting the generation of ROS.This study presents a novel approach for developing highly effective photocatalysts that follows a new mechanism to eliminate organic pollutants from water.
基金supported by the National Natural Science Foundation of China(NSFC)(Nos.22076063,22076098,and 21477047)the Natural Science Foundation of Shandong Province(No.ZR2020MB033)+1 种基金the Key Laboratory of Photochemical Conversion and Optoelectronic Materials,TIPC,CAS(No.PCOM202106)the program for Taishan Scholars of Shandong Province,and the Science and Technology Programof the University of Jinan(No.XKY2111).
文摘Volatile Organic Compounds(VOCs)are highly harmful to human beings and other organisms,and thus the elimination of VOCs is extremely urgent.Here,La-Si co-doped TiO_(2)microsphere photocatalysts,which were prepared by a hydrothermal method,exhibited high photocatalytic activity in the decomposition of formaldehyde compared with TiO_(2).The improved activity can be attributed to the promoted separation efficiency and density of the charge carriers,as verified by the electrochemical results in combination with density functional theory calculations.In addition,the Si dopant changed the microstructure and surface acidity,while the addition of La promoted the separation efficiency of charge carriers.More interestingly,it was found that singlet oxygen was the key species in the activation of molecular dioxygen,and it played a pivotal role in the photocatalytic decomposition of formaldehyde.This work provides a novel strategy for the selective activation of dioxygen for use in the decomposition of formaldehyde.
基金supported by the Hebei province Natural Science Foundation(No.B2023108012)the Science Research Project of Hebei Education Department(No.BJK2024137)+2 种基金the S&T Program of Xingtai(No.2023ZZ096)the National Natural Science Foundation of China(No.62004143)the Key R&D Program of Hubei Province(No.2022BAA084)。
文摘A meticulous design of the local environment at the interface between active species and the support,aimed at optimizing the adsorption of H_(2)O molecules and BH_(4)^(-)anion,offers an ideal strategy for enhancing hydrogen generation via Na BH4hydrolysis through dual activation pathways.Theoretical predictions based on d-band center analysis and electron transfer calculations suggest that introducing-OH functional groups induce charge redistribution,enhancing charge concentration on alk-Ti_(3)C_(2)and facilitating the adsorption and activation of dual active species,H2O molecules and BH4-anion.Inspired by these predictions,the optimized alk-Ti_(3)C_(2)/Ru Oxcatalyst demonstrates the highest catalytic activity,achieving a hydrogen generation rate(HGR)of 9468 m L min^(-1)gcat.^(-1).Both experimental data and theoretical analyses confirm that the-OH functional groups promote charge enrichment on alk-Ti_(3)C_(2),optimizing the adsorption of H_(2)O molecules and BH_(4)^(-)anion,and reducing the dissociation energy barrier of the*OH–H-TS intermediate.This dual activation pathways mechanism lowers the activation energy for Na BH4hydrolysis,significantly enhancing the HGR performance.These findings,guided by theoretical insights,establish alk-Ti_(3)C_(2)/Ru Oxas an efficient catalyst for Na BH4hydrolysis and provide a strong foundation for future hydrogen generation catalyst designs.
文摘AIM: To investigate the effect of herbal compound 861 (Cpd861) on the transforming growth factor-β1 (TGFβ1)/ activin receptor-like kinase 1 (ALK1, type Ⅰ receptor) signaling-pathway-related gene expression in the LX-2 cell line, and the inhibitory mechanism of Cpd861 on the activation of LX-2 cells. METHODS: LX-2 cells were treated with TGFβ1 (5 ng/mL) Cpd861 (0.1 mg/mL), TGFβ1 (5 ng/mL) plus Cpd861 (5 ng/mL) for 24 h to investigate the effect of Cpd861 on the TGFβ1/ALK1 pathway. Real-time PCR was performed to examine the expression of α-SMA (α-smooth muscle actin), ALK1, Id1 (inhibitor of differentiation 1). Western blotting was carried out to measure the levels of α-SMA and phosphorylated Smad1, and immunocytochemical analysis for the expression of α-SMA. RESULTS: In LX-2 cells, TGFβ1/ALK1-pathway-related gene expression could be stimulated by TGFβ1, which led to excessive activation of the cells. Cpd861 decreased the activation of LX-2 cells by reducing the expression of α-SMA mRNA and protein expression. This effect was related to inhibition of the above TGFβ1/ALK1-pathway- related expression of genes such as Id1 and ALK1, and phosphorylation of Smad1 in LX-2 cells, even with TGFβ1 co-treatment for 24 h. CONCLUSION: Cpd861 can restrain the activation of LX-2 cells by inhibiting the TGFβ1/ALK1/Smad1 pathway.
基金Supported by grants from the Institute de Salud Carlos III No.C03/02,No. G03/156
文摘AIM: To assess the usefulness of urinary trypsinogen-2 test strip, urinary trypsinogen activation peptide (TAP),and serum and urine concentrations of the activation peptide of carboxypeptidase B (CAPAP) in the diagnosisof acute pancreatitis.METHODS: Patients with acute abdominal pain and hospitalized within 24 h after the onset of symptoms were prospectively studied. Urinary trypsinogen-2 was considered positive when a clear blue line was observed (detection limit 50 μg/L). Urinary TAP was measured using a quantitative solid-phase ELISA, and serum and urinary CAPAP by a radioimmunoassay method.RESULTS: Acute abdominal pain was due to acute pancreatitis in 50 patients and turned out to be extrapancreatic in origin in 22 patients. Patients with acute pancreatitis showed significantly higher median levels of serum and urinary CAPAP levels, as well as amylase and lipase than extrapancreatic controls. Median TAP levels were similar in both groups. The urinary trypsinogen-2 test strip was positive in 68% of patients with acute pancreatitis and 13.6% in extrapancreatic controls (P<0.01). Urinary CAPAP was the most reliable test for the diagnosis of acute pancreatitis (sensitivity 66.7%, specificity 95.5%, positive and negative predictive values 96.6% and 56.7%, respectively), with a 14.6 positive likelihood ratio for a cut-off value of 2.32 nmol/L.CONCLUSION: In patients with acute abdominal pain,hospitalized within 24 h of symptom onset, CAPAP in serum and urine was a reliable diagnostic marker of acute pancreatitis. Urinary trypsinogen-2 test strip showed a clinical value similar to amylase and lipase.Urinary TAP was not a useful screening test for the diagnosis of acute pancreatitis.
基金Supported by the National Natural Science Foundation of China(No.29936100).
文摘The CO2 adsorption data may show more than one section in the Dubinin-Radushkevich-Kaganer(DRK) plot if samples had been over-activated. Each section in the plot represents a range of pore size. The whole DRK plot provided information on the pore size distribution(PSD) of a sample, which may be used to monitor the effect of activation conditions in activation processes.
文摘Indoleamine 2, 3-dioxygenase (IDO) is a rate-limiting enzyme for the tryptophan catabolism. In human and murine cells, IDO inhibits antigen-specific T cell proliferation in vitro and suppresses T cell responses to fetal alloantigens during murine pregnancy. In mice, IDO expression is an inducible feature of specific subsets of dendritic cells (DCs), and is important for T cell regulatory properties. However, the effect of IDO and tryptophan deprivation on DC func- tions remains unknown. We report here that when tryptophan utilization was prevented by a pharmacological inhibitor of IDO, 1-methyl tryptophan (1MT), DC activation induced by pathogenic stimulus lipopolysaccharide (LPS) or inflam- matory cytokine TNF-α was inhibited both phenotypically and functionally. Such an effect was less remarkable when DC was stimulated by a physiological stimulus, CD40 ligand. Tryptophan deprivation during DC activation also regu- lated the expression of CCR5 and CXCR4, as well as DC responsiveness to chemokines. These results suggest that tryptophan usage in the microenvironment is essential for DC maturation, and may also play a role in the regulation of DC migratory behaviors.
