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Progress in MOF-based catalyst design and reaction mechanisms for CO_(2)hydrogenation to methanol
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作者 YU Zhifu JIANG Lei WU Mingbo 《燃料化学学报(中英文)》 北大核心 2026年第1期146-162,共17页
Against the backdrop of escalating global climate change and energy crises,the resource utilization of carbon dioxide(CO_(2)),a major greenhouse gas,has become a crucial pathway for achieving carbon peaking and carbon... Against the backdrop of escalating global climate change and energy crises,the resource utilization of carbon dioxide(CO_(2)),a major greenhouse gas,has become a crucial pathway for achieving carbon peaking and carbon neutrality goals.The hydrogenation of CO_(2)to methanol not only enables carbon sequestration and recycling,but also provides a route to produce high value-added fuels and basic chemical feedstocks,holding significant environmental and economic potential.However,this conversion process is thermodynamically and kinetically limited,and traditional catalyst systems(e.g.,Cu/ZnO/Al_(2)O_(3))exhibit inadequate activity,selectivity,and stability under mild conditions.Therefore,the development of novel high-performance catalysts with precisely tunable structures and functionalities is imperative.Metal-organic frameworks(MOFs),as crystalline porous materials with high surface area,tunable pore structures,and diverse metal-ligand compositions,have the great potential in CO_(2)hydrogenation catalysis.Their structural design flexibility allows for the construction of well-dispersed active sites,tailored electronic environments,and enhanced metal-support interactions.This review systematically summarizes the recent advances in MOF-based and MOF-derived catalysts for CO_(2)hydrogenation to methanol,focusing on four design strategies:(1)spatial confinement and in situ construction,(2)defect engineering and ion-exchange,(3)bimetallic synergy and hybrid structure design,and(4)MOF-derived nanomaterial synthesis.These approaches significantly improve CO_(2)conversion and methanol selectivity by optimizing metal dispersion,interfacial structures,and reaction pathways.The reaction mechanism is further explored by focusing on the three main reaction pathways:the formate pathway(HCOO*),the RWGS(Reverse Water Gas Shift reaction)+CO*hydrogenation pathway,and the trans-COOH pathway.In situ spectroscopic studies and density functional theory(DFT)calculations elucidate the formation and transformation of key intermediates,as well as the roles of active sites,metal-support interfaces,oxygen vacancies,and promoters.Additionally,representative catalytic performance data for MOFbased systems are compiled and compared,demonstrating their advantages over traditional catalysts in terms of CO_(2)conversion,methanol selectivity,and space-time yield.Future perspectives for MOF-based CO_(2)hydrogenation catalysts will prioritize two main directions:structural design and mechanistic understanding.The precise construction of active sites through multi-metallic synergy,defect engineering,and interfacial electronic modulation should be made to enhance catalyst selectivity and stability.In addition,advanced in situ characterization techniques combined with theoretical modeling are essential to unravel the detailed reaction mechanisms and intermediate behaviors,thereby guiding rational catalyst design.Moreover,to enable industrial application,challenges related to thermal/hydrothermal stability,catalyst recyclability,and cost-effective large-scale synthesis must be addressed.The development of green,scalable preparation methods and the integration of MOF catalysts into practical reaction systems(e.g.,flow reactors)will be crucial for bridging the gap between laboratory research and commercial deployment.Ultimately,multi-scale structure-performance optimization and catalytic system integration will be vital for accelerating the industrialization of MOF-based CO_(2)-to-methanol technologies. 展开更多
关键词 CO_(2)hydrogenation metal-organic frameworks(MOFs) catalyst design reaction mechanism METHANOL
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Investigation into the Effect and Microscopic Mechanism of Retarders on Two-component Backfilling Grout in Shield Engineering
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作者 CAI Hongwei MIN Fanlu +5 位作者 YUAN Rui LI Zhen ZHANG Jianfeng WANG Dengfeng ZHANG Yazhou YAO Zhanhu 《Journal of Wuhan University of Technology(Materials Science)》 2026年第1期84-95,共12页
To address the issues of short setting time and high bleeding rate of A component,which easily cause pipe plugging and poor grouting performance when a two-component grout is injected synchronously behind the Segmenta... To address the issues of short setting time and high bleeding rate of A component,which easily cause pipe plugging and poor grouting performance when a two-component grout is injected synchronously behind the Segmental Lining,the inorganic retarder sodium pyrophosphate(TSPP)and three organic retarders were added to the A component:sodium citrate(SC),sodium tartrate(ST)and glycerol(GLY).The effect law and microscopic mechanism of viscosity,bleeding rate,setting time,gelling time,compressive strength,and stone rate were investigated.The results revealed that the addition of retarders could enhance the stability and setting time of the A component and increase the gelling time,stone rate,and compressive strength of two-component grout.Among them,the performance of the grout with an SC dosage of 0.1% was superior.The bleeding rate of this grout was reduced to 3.5%,the stone rate of the two-component grout was more than 99%,and the early compressive strength and late compressive strength of this grout were increased by approximately 35% and 7%,respectively.The initial and final setting time of the A component with a TSPP dosage of 0.3% was the longest,which was prolonged to 17 and 26 h,respectively.Microscopic analysis revealed that the four retarders hindered the hydration process of cement through complexation and adsorption,and inhibited the hydration of C_(3)S and the crystallisation of CH.Moreover,they reduced the defects caused by the rapid reaction of water glass and CH on the solid phase structure,enabled the microstructure of the stone body to be denser,and subsequently,enhanced the compressive strength. 展开更多
关键词 backfilling grout two-component grout RETARDER working performance gelling performance microscopic mechanism
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Towards mechanism-based tau-targeted therapies
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作者 Lidia Bakota Roland Brandt 《Neural Regeneration Research》 2026年第2期687-688,共2页
Tau plays a crucial role in several neurodegenerative diseases,collectively referred to as tauopathies.Therefore,targeting potential pathological changes in tau could enable useful therapeutic interventions.However,ta... Tau plays a crucial role in several neurodegenerative diseases,collectively referred to as tauopathies.Therefore,targeting potential pathological changes in tau could enable useful therapeutic interventions.However,tau is not an easy target because it dynamically interacts with microtubules and other cellular components,which presents a challenge for tau-targeted drugs.New cellular models could aid the development of mechanism-based tau-targeted therapies. 展开更多
关键词 tau targeted therapies cellular components mechanism based therapies cellular componentswhich cellular models MICROTUBULES TAUOPATHIES neurodegenerative diseasescollectively
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Performance and Microscopic Influence Mechanism of Solidified Cadmium Contaminated Soil by Rice Husk Ash Based Geopolymer
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作者 CHEN Wei HAN Jianhong +5 位作者 YU Hongbao XU Hong WANG Ying FAN Wenxiao ZHAO Lina LIU Peijie 《Journal of Wuhan University of Technology(Materials Science)》 2026年第1期171-178,共8页
In order to realize the comprehensive utilization of industrial solid waste rice husk ash and heavy metal cadmium contaminated soil,rice husk ash-based geopolymer prepared by alkaline activator was used to modify cadm... In order to realize the comprehensive utilization of industrial solid waste rice husk ash and heavy metal cadmium contaminated soil,rice husk ash-based geopolymer prepared by alkaline activator was used to modify cadmium contaminated soil.The main physical and chemical properties of rice husk ash were clarified by SEM,XRF and X-ray diffraction.The unconfined compressive strength test and toxicity leaching test were carried out on the modified soil.Combined with FTIR and TG micro-level,the solidification mechanism of rice husk ash-based geopolymer solidified cadmium contaminated soil was discussed.The results show that the strength of geopolymer modified soil is significantly higher than that of plain soil,and the unconfined compressive strength at 7 d age is 4.2 times that of plain soil.The strength of modified soil with different dosage of geopolymer at 28 d age is about 36% to 40% higher than that of modified soil at 7 d age.Geopolymer has a significant effect on the leaching of heavy metals in contaminated soil.When the cadmium content is 100 mg/kg,it meets the standard limit.In the process of complex depolymerization-condensation reaction,on the one hand,geopolymers are cemented and agglomerated to form a complex spatial structure,which affects the macro and micro characteristics of soil.On the other hand,it has significant adsorption,precipitation and replacement effects on heavy metal ions in soil,showing good strength and low heavy metal leaching toxicity. 展开更多
关键词 rice husk ash alkali excitation heavy metals curing mechanism
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Integrating high-resolution mass spectrometry and transcriptomics to explore the therapeutic mechanism of Sanhuang Oil in diabetic foot
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作者 Ping Sun Yu-Feng Zhang +4 位作者 Shuang Li Wei Zhang Peng-Fei Zhao Chen-Xia Li Chen-Ning Zhang 《Traditional Medicine Research》 2026年第1期19-38,共20页
Background:Diabetic foot,a severe complication of diabetes,is characterized by chronic refractory wounds.Sanhuang Oil,a topical herbal formula,demonstrates significant therapeutic effects including antibacterial,anti-... Background:Diabetic foot,a severe complication of diabetes,is characterized by chronic refractory wounds.Sanhuang Oil,a topical herbal formula,demonstrates significant therapeutic effects including antibacterial,anti-inflammatory,and immunomodulatory activities.However,its active constituents and mechanisms of action against diabetic foot remain to be elucidated.Methods:In this study,the chemical constituents of Sanhuang Oil were identified using UPLC-QE-Orbitrap-MS.Subsequently,the mechanism by which Sanhuang Oil promotes diabetic foot ulcer healing was predicted by integrating network pharmacology and molecular docking.Additionally,diabetic mouse model was established in ICR mice using a combination of a high-fat diet(HFD)and streptozotocin(STZ)chemical induction.A full-thickness skin defect was created on the dorsum of the mice.Wound healing and the healing rate were observed following Sanhuang Oil intervention.The mechanism underlying Sanhuang Oil’s promotion of diabetic ulcer healing was further investigated using transcriptomics and histopathological examination(H&E staining).Results:A total of 97 active ingredients were identified from Sanhuang Oil.Network pharmacology analysis predicted 543 common targets,and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analysis identified 203 relevant pathways.Molecular docking further confirmed high binding affinity(binding energy≤−5.0 kcal/mol)between specific active components in Sanhuang Oil(e.g.,coptisine,phellodendrine,baicalein)and key targets associated with diabetic foot ulcers(e.g.,EGFR,AKT1,STAT3).In vivo experimental results demonstrated that the wound healing rate was significantly higher in Sanhuang Oil-treated groups compared to the model group(P<0.001).HE staining revealed that the high-dose Sanhuang Oil group exhibited more pronounced epithelial tissue coverage over the wound,reduced inflammatory cell infiltration,and increased collagen deposition and fibroblast proliferation.transcriptomic analysis identified Pdk4,Ttn,Csrp3,Actn2,Myoz2,Tnnc2,Myod1,Myog,Myot,and Myf6 as key regulatory proteins involved in promoting wound healing.Conclusion:Sanhuang Oil promotes wound healing in diabetic ulcer mice,potentially by mitigating inflammation and regulating key targets such as Pdk4 to enhance fibroblast function.These findings provide novel insights into the multi-target,multi-pathway mechanism of Sanhuang Oil for treating diabetic foot ulcers. 展开更多
关键词 Sanhuang Oil diabetic foot high-resolution mass spectrometry molecular network analysis mechanism of action
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Therapeutic potential of traditional Chinese medicine for the treatment of chemotherapy-induced diarrhea:clinical efficacy and underlying mechanisms
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作者 Yun-Jing He Wei-Jian Chen Ke Nie 《Traditional Medicine Research》 2026年第1期75-99,共25页
Chemotherapy-induced diarrhea(CID)is a major concern for cancer patients and is associated with significant morbidity and mortality.Currently,the clinical management of CID is limited.The utilization of antidiarrheal ... Chemotherapy-induced diarrhea(CID)is a major concern for cancer patients and is associated with significant morbidity and mortality.Currently,the clinical management of CID is limited.The utilization of antidiarrheal medications,such as loperamide and octreotide,is relatively limited because of their unsatisfactory efficacy and adverse effects.In recent years,traditional Chinese medicine(TCM)has attracted great interest because of its beneficial effect in treating CID,which has multitarget and low-toxicity therapeutic characteristics.TCM exhibits remarkable therapeutic potential in the prevention and treatment of CID.It can alleviate and treat CID by regulating chemical drug metabolism,improving the integrity of the intestinal barrier,stimulating proliferation while suppressing the apoptosis of intestinal epithelial cells,ameliorating oxidative stress and inflammation and regulating bile acids and aquaporins.However,large-scale,randomized,double-blind clinical trials of TCM for the treatment of CID are lacking,and most preclinical experiments have not been translated to clinical trials.Accordingly,this review highlights the clinical efficacy and molecular mechanisms of TCM against CID via PubMed,Web of Science and China National Knowledge Infrastructure and proposes that future research on TCM against CID should focus on strengthening the connection from bench to bed,which may help to comprehensively evaluate the therapeutic potential of TCM against CID. 展开更多
关键词 traditional Chinese medicine chemotherapy-induced diarrhea clinical efficacy pharmacological mechanism
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Recent Advances in Regulation Strategy and Catalytic Mechanism of Bi-Based Catalysts for CO_(2) Reduction Reaction
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作者 Jianglong Liu Yunpeng Liu +5 位作者 Shunzheng Zhao Baotong Chen Guang Mo Zhongjun Chen Yuechang Wei Zhonghua Wu 《Nano-Micro Letters》 2026年第1期647-697,共51页
Using photoelectrocatalytic CO_(2) reduction reaction(CO_(2)RR)to produce valuable fuels is a fascinating way to alleviate environmental issues and energy crises.Bismuth-based(Bi-based)catalysts have attracted widespr... Using photoelectrocatalytic CO_(2) reduction reaction(CO_(2)RR)to produce valuable fuels is a fascinating way to alleviate environmental issues and energy crises.Bismuth-based(Bi-based)catalysts have attracted widespread attention for CO_(2)RR due to their high catalytic activity,selectivity,excellent stability,and low cost.However,they still need to be further improved to meet the needs of industrial applications.This review article comprehensively summarizes the recent advances in regulation strategies of Bi-based catalysts and can be divided into six categories:(1)defect engineering,(2)atomic doping engineering,(3)organic framework engineering,(4)inorganic heterojunction engineering,(5)crystal face engineering,and(6)alloying and polarization engineering.Meanwhile,the corresponding catalytic mechanisms of each regulation strategy will also be discussed in detail,aiming to enable researchers to understand the structure-property relationship of the improved Bibased catalysts fundamentally.Finally,the challenges and future opportunities of the Bi-based catalysts in the photoelectrocatalytic CO_(2)RR application field will also be featured from the perspectives of the(1)combination or synergy of multiple regulatory strategies,(2)revealing formation mechanism and realizing controllable synthesis,and(3)in situ multiscale investigation of activation pathways and uncovering the catalytic mechanisms.On the one hand,through the comparative analysis and mechanism explanation of the six major regulatory strategies,a multidimensional knowledge framework of the structure-activity relationship of Bi-based catalysts can be constructed for researchers,which not only deepens the atomic-level understanding of catalytic active sites,charge transport paths,and the adsorption behavior of intermediate products,but also provides theoretical guiding principles for the controllable design of new catalysts;on the other hand,the promising collaborative regulation strategies,controllable synthetic paths,and the in situ multiscale characterization techniques presented in this work provides a paradigm reference for shortening the research and development cycle of high-performance catalysts,conducive to facilitating the transition of photoelectrocatalytic CO_(2)RR technology from the laboratory routes to industrial application. 展开更多
关键词 Bismuth-based catalysts CO_(2)reduction reaction Regulation strategy Catalytic mechanism REVIEW
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Scutellaria baicalensis Georgi as a potential therapeutic drug intervention in ulcerative colitis:Mechanisms of action and clinical trials
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作者 Yi Ding Chu-Ye Wang +3 位作者 Ya-Ting Pan Yu-Jia Wang Ai-Guang Zhao Hong-Zhu Wen 《World Journal of Gastroenterology》 2026年第1期88-109,共22页
Ulcerative colitis (UC) is a chronic inflammatory bowel disease characterized byclinical symptoms of diarrhea and mucopurulent bloody stools, and its incidenceis increasing globally. The etiology and pathogenesis of U... Ulcerative colitis (UC) is a chronic inflammatory bowel disease characterized byclinical symptoms of diarrhea and mucopurulent bloody stools, and its incidenceis increasing globally. The etiology and pathogenesis of UC remain elusive. Currenttherapeutic approaches, including anti-inflammatory, immunosuppressiveand immunomodulating agents, are often limited in efficacy and frequently associatedwith adverse drug reactions. Therefore, there is an urgent need to developsafer and more effective treatment strategies to address the limitations of existingtherapies. Scutellaria baicalensis Georgi (HQ), a traditional Chinese medicinal herb,has been employed in the treatment of UC for over 2000 years. Recent studieshave demonstrated that HQ contains multiple active components capable oftreating UC through anti-inflammation, immune modulation, intestinal barrierprotection, antioxidant activity, and regulation of the gut microbiota. This paperreviews recent studies on the mechanism of action and clinical trials of HQ intreating UC based on relevant literature, with the aim of providing valuable insightsinto future treatment approaches. 展开更多
关键词 Ulcerative colitis Scutellaria baicalensis Georgi mechanism of action Clinical trials Traditional Chinese medicine therapy
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Performance and Mechanism Study of Solidifying Zinc-Contaminated Soil Using Red Mud-Carbide Slag-Phosphogypsum Synergistic Cement
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作者 ZHANG Jieya YANG Zhen +1 位作者 WU Min DONG Xiaoqiang 《Journal of Wuhan University of Technology(Materials Science)》 2026年第1期96-106,共11页
We used solidification/stabilization methods to remediate highly concentrated Zn^(2+)-contaminated soil.An industrial waste mixture of red mud,carbide slag,and phosphogypsum is combined with cement as the curing agent... We used solidification/stabilization methods to remediate highly concentrated Zn^(2+)-contaminated soil.An industrial waste mixture of red mud,carbide slag,and phosphogypsum is combined with cement as the curing agent.The mixing ratios of the four materials are determined by comparing the strength,permeability coefficient,pH,and Zn^(2+)-leaching concentration of the solidified soil.Microscopic characteristics of the solidified uncontaminated soil and solidified Zn^(2+)-contaminated soil were observed using scanning electron microscopy,X-ray diffraction,and Fourier-transform infrared spectroscopy.Furthermore,the heavy metals speciation in both pure cement and mixed-material solidified soil was examined,demonstrating the beneficial role of the mixed-type curing agent in stabilizing heavy metals.The research results indicate that Zn^(2+)degrade the strength of the solidified soil by up to 90%.The permeability coefficient,pH,and Zn^(2+)-leaching concentration of the solidified soil easily meet standard,especially with Zn^(2+)leaching concentration well below the environmental protection limit.Furthermore,most Zn^(2+)exists in forms with lower biological and chemical reactivity.Both the solidified Zn^(2+)-contaminated soil and uncontaminated soil resulted in the formation of hydrated products containing elements such as silicon,aluminum,calcium,and sulfur.Additionally,the solidified Zn^(2+)-contaminated soil produced zinc-containing compounds and a large amount of rod-shaped ettringite. 展开更多
关键词 SOLIDIFICATION/STABILIZATION Zn^(2+)-contaminated soil engineering characteristics environmental indicators solidification mechanism
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Regulatory T cells in neurological disorders and tissue regeneration:Mechanisms of action and therapeutic potentials
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作者 Jing Jie Xiaomin Yao +5 位作者 Hui Deng Yuxiang Zhou Xingyu Jiang Xiu Dai Yumin Yang Pengxiang Yang 《Neural Regeneration Research》 2026年第4期1277-1291,共15页
Regulatory T cells,a subset of CD4^(+)T cells,play a critical role in maintaining immune tolerance and tissue homeostasis due to their potent immunosuppressive properties.Recent advances in research have highlighted t... Regulatory T cells,a subset of CD4^(+)T cells,play a critical role in maintaining immune tolerance and tissue homeostasis due to their potent immunosuppressive properties.Recent advances in research have highlighted the important therapeutic potential of Tregs in neurological diseases and tissue repair,emphasizing their multifaceted roles in immune regulation.This review aims to summarize and analyze the mechanisms of action and therapeutic potential of Tregs in relation to neurological diseases and neural regeneration.Beyond their classical immune-regulatory functions,emerging evidence points to non-immune mechanisms of regulatory T cells,particularly their interactions with stem cells and other non-immune cells.These interactions contribute to optimizing the repair microenvironment and promoting tissue repair and nerve regeneration,positioning non-immune pathways as a promising direction for future research.By modulating immune and non-immune cells,including neurons and glia within neural tissues,Tregs have demonstrated remarkable efficacy in enhancing regeneration in the central and peripheral nervous systems.Preclinical studies have revealed that Treg cells interact with neurons,glial cells,and other neural components to mitigate inflammatory damage and support functional recovery.Current mechanistic studies show that Tregs can significantly promote neural repair and functional recovery by regulating inflammatory responses and the local immune microenvironment.However,research on the mechanistic roles of regulatory T cells in other diseases remains limited,highlighting substantial gaps and opportunities for exploration in this field.Laboratory and clinical studies have further advanced the application of regulatory T cells.Technical advances have enabled efficient isolation,ex vivo expansion and functionalization,and adoptive transfer of regulatory T cells,with efficacy validated in animal models.Innovative strategies,including gene editing,cell-free technologies,biomaterial-based recruitment,and in situ delivery have expanded the therapeutic potential of regulatory T cells.Gene editing enables precise functional optimization,while biomaterial and in situ delivery technologies enhance their accumulation and efficacy at target sites.These advancements not only improve the immune-regulatory capacity of regulatory T cells but also significantly enhance their role in tissue repair.By leveraging the pivotal and diverse functions of Tregs in immune modulation and tissue repair,regulatory T cells–based therapies may lead to transformative breakthroughs in the treatment of neurological diseases. 展开更多
关键词 demyelinating diseases gene editing immune regulation immune tolerance neural regeneration neurological diseases non-immune mechanisms regulatory T cells stem cells STROKE tissue homeostasis tissue repair
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Unveiling complexities:Reviews on insights into the mechanism of oxygen evolution reaction
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作者 Pengxiang Zhang Jiawen Wang +7 位作者 Tianyu Yang Ruizhe Wang Ruofan Shen Zhikun Peng Yanyan Liu Xianli Wu Jianchun Jiang Baojun Li 《Chinese Journal of Catalysis》 2025年第5期48-83,共36页
The study of the oxygen evolution reaction(OER)mechanism is vital for advancing our understanding of this pivotal energy conversion process.This review synthesizes recent advancements in OER mechanism,emphasizing the ... The study of the oxygen evolution reaction(OER)mechanism is vital for advancing our understanding of this pivotal energy conversion process.This review synthesizes recent advancements in OER mechanism,emphasizing the intricate relationship between catalytic mechanisms and catalyst design.This review discusses the connotation and cutting-edge progress of traditional mechanisms such as adsorbate evolution mechanism(AEM)and lattice oxygen mechanism(LOM)as well as emerging pathways including oxide path mechanism(OPM),oxo-oxo coupling mechanism(OCM),and intramolecular oxygen coupling mechanism(IMOC)etc.Innovative research progress on the coexistence and transformation of multiple mechanisms is highlighted,and the intrinsic factors that influence these dynamic processes are summarized.Advanced characterization techniques and theoretical modeling are underscored as indispensable tools for revealing these complex interactions.This review provides guiding principles for mechanism-based catalyst design.Finally,in view of the multidimensional challenges currently faced by OER mechanisms,prospects for future research are given to bridge the gap between mechanism innovation and experimental verification and application.This comprehensive review provides valuable perspectives for advancing clean energy technologies and achieving sustainable development. 展开更多
关键词 Oxygen evolution reaction Catalytic mechanism Catalyst design Adsorption evolution mechanism Lattice oxygen mechanism
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Reducing bentonite usage in iron ore pelletization through synergistic modification with mechanical force and DMSO:Effects and mechanisms
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作者 Yinrui Dong Yongbin Yang +4 位作者 Lin Wang Qianqian Duan Qian Li Yan Zhang Tao Jiang 《International Journal of Minerals,Metallurgy and Materials》 2026年第1期177-190,共14页
Bentonite is a necessary binder in producing pellets.Its excessive use reduces the iron grade of pellets and increases production costs.Minimizing bentonite dosage is essential for producing high-quality iron ore pell... Bentonite is a necessary binder in producing pellets.Its excessive use reduces the iron grade of pellets and increases production costs.Minimizing bentonite dosage is essential for producing high-quality iron ore pellets.Addressing the gap in the application of organically-intercalated modified bentonite in the pelletizing field,this study introduces an innovative modification process for bentonite that employs the synergistic effect of mechanical force and dimethyl sulfoxide to enhance the intercalation of organic compounds within bentonite,thus significantly enhancing its binding performance.The colloid value and swell capacity of modified bentonite(98.5 m L/3g and 55.0 m L/g)were much higher than the original bentonite(90.5 m L/3g and 17.5 m L/g).With the decrease of bentonite dosage from1.5wt%to 1.0wt%,the drop number of green pellets from a height of 0.5 m and the compressive strengths of roasted pellets using the modified bentonite(6.0 times and 2916 N per pellet)were significantly higher than those of the original bentonite(4.0 times and 2739 N per pellet).This study provides a comprehensive analysis of the intercalation modification mechanism of bentonite,offering crucial technical insights for the development of high-performance modified bentonite as iron ore pellet binders. 展开更多
关键词 PELLETS bentonite modification mechanical force dimethyl sulfoxide organic intercalation
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Seismicity associated with hydraulic fracturing in Changning shale gas field,China:Constraints from source mechanisms,stress field and fluid overpressure thresholds 被引量:1
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作者 Jingjing Dai Jianfeng Liu +6 位作者 Jianxiong Yang Fujun Xue Lei Wang Xiangchao Shi Shigui Dai Jun Hu Changwu Liu 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第7期4061-4076,共16页
Source properties and stress fields are critical to understand fundamental mechanisms for fluid-induced earthquakes.In this study,we identify the focal mechanism solutions(FMSs)of 360 earthquakes with local magnitude ... Source properties and stress fields are critical to understand fundamental mechanisms for fluid-induced earthquakes.In this study,we identify the focal mechanism solutions(FMSs)of 360 earthquakes with local magnitude M_(L)≥1.5 in the Changning shale gas field from January 2016 to May 2017 by fitting three-component waveforms.We then constrain the directions of the maximum horizontal stress(σ_(H_(max)))for four dense earthquake clusters using the stress tensor inversion method.The stress drops of 121 earthquakes with M_(L)≥1.5 are calculated using the spectral ratio method.We examine the spatiotemporal heterogeneity of stress field,and discuss the cause of non-double-couple(non-DC)components in seismicity clusters.Following the Mohr-Coulomb criterion,we estimate the fluid overpressure thresholds from FMS for different seismic clusters,providing insights into potential physical mechanisms for induced seismicity.The FMS results indicate that shallow reverse earthquakes,with steep dip angles,characterize most events.The source mechanisms of earthquakes with M_(L)≥1.5 are dominated by DC components(>70%),but several earthquakes with M_(L)>3.0 and the microseismic events nearby during injection period display significant non-DC components(>30%).Stress inversion results reveal that the σ_(H_(max)) direction ranges from 120°to 128°.Stress drops of earthquakes range between 0.10 and 64.49 MPa,with high values occurring on reverse faults situated at a greater distance from the shale layer,accompanied by a moderate rotation(≤25°)in the trend of σ_(H_(max)).The seismic clusters close to the shale layer exhibit low fluid overpressure thresholds,prone to being triggered by high pore-pressure fluid.The integrated results suggest that the diffusion of high pore pressures is likely to be the primary factor for observed earthquakes.The present results are expected to offer valuable insights into the origin of anomalous seismicity near the shale gas sites. 展开更多
关键词 SEISMICITY Sichuan basin Hydraulic fracturing Focal mechanism solution Stress field Triggering mechanism
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Effects of the oxygen transport properties of electrolytes on the reaction mechanisms in lithium-oxygen batteries
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作者 Aijing Yan Zhuojun Zhang +1 位作者 Xu Xiao Peng Tan 《中国科学技术大学学报》 北大核心 2025年第2期35-42,34,I0001,I0002,共11页
Lithium-oxygen batteries attract considerable attention due to exceptionally high theoretical energy density,while the development remains in its early stage.As is widely suggested,the solution mechanism induces great... Lithium-oxygen batteries attract considerable attention due to exceptionally high theoretical energy density,while the development remains in its early stage.As is widely suggested,the solution mechanism induces greater discharge capacity,while the surface mechanism induces greater cycle stability.Therefore,battery performance can be improved by adjusting the reaction mechanism.Previous studies predominantly focus on extremely thin or flat electrodes.In contrast,this work utilizes thick electrodes,emphasizing the importance of mass transport.Given that the electrolyte solvent is the main site of mass transport,the effects of two typical solvents on mass transport and battery performance are investigated:dimethyl sulfoxide with low viscosity and a high O_(2) diffusion rate and tetraethylene glycol dimethyl ether with high O_(2) solubility and high Li+transport capability.The results reveal a novel pathway for reaction mechanism induction where the mechanism varies with the spatial position of the electrode.As the spatial distribution of the electrode progresses,a layered appearance of solution mechanism products,transition state products,and surface mechanism products emerges,which is attributed to the increase in the mass transfer resistance.This work presents a distinct perspective on the way solvents influence reaction pathways and offers a new approach to regulating reaction pathways. 展开更多
关键词 Li-O_(2)battery nonaqueous electrolyte oxygen transport property solution mechanism surface mechanism
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Deriving focal mechanism solutions of small to moderate earthquakes in Sichuan,China via a deep learning method
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作者 Chen Zhang Ji Zhang Jie Zhang 《Earthquake Research Advances》 2025年第3期36-46,共11页
As one of the most seismically active regions,Sichuan Basin is a key area of seismological studies in China.This study applies a neural network model with attention mechanisms,simultaneously picking the P-wave arrival... As one of the most seismically active regions,Sichuan Basin is a key area of seismological studies in China.This study applies a neural network model with attention mechanisms,simultaneously picking the P-wave arrival times and determining the first-motion polarity.The polarity information is subsequently used to derive source focal mechanisms.The model is trained and tested using small to moderate earthquake data from June to December 2019 in Sichuan.We apply the trained model to predict first-motion polarity directions of earthquake recordings in Sichuan from January to May 2019,and then derive focal mechanism solutions using HASH algorithm with predicted results.Compared with the source mechanism solutions obtained by manual processing,the deep learning method picks more polarities from smaller events,resulting in more focal mechanism solutions.The catalog documents focal mechanism solutions of 22 events(M_(L) 2.6–4.8)from analysts during this period,whereas we obtain focal mechanism solutions of 53 events(M_(L) 1.9–4.8)through the deep learning method.The derived focal mechanism solutions for the same events are consistent with the manual solutions.This method provides an efficient way for the source mechanism inversion of small to moderate earthquakes in Sichuan region,with high stability and reliability. 展开更多
关键词 Deep learning Focal mechanism solutions Small-to-moderate earthquake First-motion polarity Attention mechanism SICHUAN
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Study of heterostructure composition by regulating lamellar LPSO phase and the related strengthening mechanism in the Mg-Gd-Y-Zn-Zr alloy
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作者 Shuangwu Xia Ping Li +3 位作者 Junfu Dong Tianle Wang Liangwei Dai Kemin Xue 《Journal of Magnesium and Alloys》 2025年第10期5199-5216,共18页
The heterostructure preparation in Mg-rare earth(RE)alloy has attracted much attention due to the excellent enhancement of strength and ductility.However,the effect of heterostructure composition on mechanical propert... The heterostructure preparation in Mg-rare earth(RE)alloy has attracted much attention due to the excellent enhancement of strength and ductility.However,the effect of heterostructure composition on mechanical properties in Mg-RE alloy is still not clear.In this work,three types of heterostructures with different composition induced by lamellar 14H long period stacking ordered(LPSO)phase were achieved in the Mg-Gd-Y-Zn-Zr alloys after cyclic extrusion and compression(CEC).The heterostructure was mainly composed of dynamic recrystallization(DRX)grains,deformed coarse grains,multiscale LPSO phase(blocky,granular,lamellar LPSO phase).The strength and ductility of Mg-Gd-Y-Zn-Zr alloy with heterostructure were simultaneously improved.The DRX behavior during CEC process was largely affected by the lamellar LPSO phase.The lamellar LPSO with large spacing(∼92 nm)and low thickness(∼13.46 nm)is easy to occur kinking behavior and the zigzag kinking area can serve as nucleation sites to promote DRX behavior.While the lamellar LPSO phase with high thickness(∼23.41 nm)and similar spacing(∼82 nm)was ruptured into granular LPSO phase and thus increase the volume fraction of granular LPSO phase,which made a great contribution to DRX behavior by particle stimulated nucleation.The main deformation mechanism of solution treatment+furnace cooling(SF)sample during CEC process is dominated by the multiple slips composed of basal slips,prismatic slips and pyramidal slips.For the solution treatment+air cooling(SA)sample and solution treatment+ageing treatment(ST)sample,the activation of basal slips is the critical deformation mechanism.The main contribution to yield strength is from the grain boundary,dislocation and hetero-deformation induced(HDI)strengthening.Moreover,the HDI strengthening in the SF and SA sample after CEC deformation is much larger than that of ST sample due to the distinct heterostructure composition. 展开更多
关键词 Mg alloys Lamellar LPSO phase HETEROSTRUCTURE Deformation mechanism Strengthening mechanism
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Concurrent occurrence of adenocarcinoma and urothelial carcinoma of the prostate:Coexistence mechanisms from multiple perspectives
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作者 Xu-Chang Liu Yu-Xiang Liu Chun Liu 《World Journal of Clinical Cases》 2025年第12期5-9,共5页
This article discusses the coexistence of prostate adenocarcinoma and prostate urothelial carcinoma.Combining existing literature and research results,the potential mechanisms of the co-occurrence of these two cancers... This article discusses the coexistence of prostate adenocarcinoma and prostate urothelial carcinoma.Combining existing literature and research results,the potential mechanisms of the co-occurrence of these two cancers are explored,including the role of androgen receptor,gene mutations,and their complex interactions in cell signaling pathways,etc.Also,the hypothesis of prostate cancer transformation into urothelial carcinoma is explained from some perspectives,including tumor multipotent stem cell differentiation,epithelial-mesenchymal transition,mesenchymal-epithelial transition,and other mechanisms.Ultimately,the goal is to provide more accurate diagnoses and more personalized treatments in clinical practice,as well as to lay the foundation for improving patient prognoses in the future. 展开更多
关键词 Prostate adenocarcinoma Prostate urothelial carcinoma Coexistence mechanism Transformation mechanism TUMOR
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The seismic mechanisms and seismogenic environment of the M_(s)6.2 earthquake in Jishishan,Gansu,China:Evidence from relocation,focal mechanisms,and rupture processes
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作者 TaiRan Xu ZhiGao Yang +5 位作者 DanQing Dai Ming Zhi JianYong Zhang GuangBao Du Nan Xi Li Sun 《Earth and Planetary Physics》 2025年第2期309-322,共14页
On December 18,2023,an M_(s)6.2 earthquake jolted Jishishan County in the Linxia Hui Autonomous Prefecture in Northwest China's Gansu Province,causing substantial casualties and building collapses.The earthquake o... On December 18,2023,an M_(s)6.2 earthquake jolted Jishishan County in the Linxia Hui Autonomous Prefecture in Northwest China's Gansu Province,causing substantial casualties and building collapses.The earthquake occurred in the Qilian Block on the northeastern border of the Qinghai-Tibet Plateau,where faults are highly active and the geological structure is complex.In this study,we utilized methods such as relocation,focal mechanism solutions,and earthquake rupture processes to describe seismogenic faults.The results indicated that the majority of aftershocks occurred at a depth of 12 km.The centroid depth of the main shock and the depth of the maximum rupture point during the rupture process were also 12 km.Various geophysical methods exhibited a high degree of consistency in depth exploration.Aftershocks were distributed mainly to the west and north of the main shock and extended in the NNW direction,primarily through unilateral rupture.The main shock was a reverse thrust event with a small dextral strike-slip component.In this study,more regional data,such as previous GPS observations,field geological observations,and the distributions of the primary stress states in the region,were also incorporated.We inferred that the main shock was triggered by the main fault at the northern margin of the Lajishan Fault and that the movement of the main fault also activated some secondary faults.The compressive forces on both sides of the Lajishan Fault Zone led to the uplift of mountain areas,accompanied by some landslides,leading to this catastrophic earthquake event.In this article,the activity relationships among the 2022 M_(s)6.9 Menyuan earthquake,the 2019 M_(s)5.7 Xiahe earthquake,and the Jishishan earthquake under the action of regional stress are also discussed.This study provides additional evidence and new ideas for exploring the seismogenic process of the Lajishan Fault Zone and has implications for future in-depth research on underground activity in this region. 展开更多
关键词 RELOCATION focal mechanism earthquake rupture process Lajishan Fault seismic mechanism
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Deformation Mechanism and Fracture Behavior of a Coarse-Grain Ni-Co-Based Superalloy During Superplasticity
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作者 Rashad AAl-Hammadi Rui Zhang +2 位作者 Chuanyong Cui Xipeng Tao Yizhou Zhou 《Acta Metallurgica Sinica(English Letters)》 2025年第11期2024-2034,共11页
The advent of coarse-grain superplasticity has provided a pathway for novel applications in material forming.This article investigated the underlying deformation mechanisms that enabled achieving superplastic elongati... The advent of coarse-grain superplasticity has provided a pathway for novel applications in material forming.This article investigated the underlying deformation mechanisms that enabled achieving superplastic elongation exceeding 230%in a coarse-grained Ni-Co-based superalloy.The deformed microstructure and fractographic characteristics of the alloy were examined utilizing optical microscopy(OM),scanning electron microscopy(SEM),and electron backscatter diffraction(EBSD).The results of the analysis revealed that below 1100℃,the process of dynamic recrystallization(DRX)occurred at a sluggish rate,resulting in low plasticity and the initiation of severe cracks.Complete DRX occurred when the deformation temperature exceeded 1100℃,leading to a more uniformly deformed microstructure,reduced crack initiation,and enhanced ductility demonstrated by elongation to failure surpassing 230%.The augmented occurrence of the DRX facilitated prolonged plastic-forming periods,which delayed fracture propagation and promoted the deformation flow within the alloy,thereby transitioning the fracture behavior from intergranular-brittle at 1050℃to ductile intergranular at 1140℃.At this temperature,the deformation was predominantly governed by the discontinuous-DRX(DDRX)mechanism and grain growth,facilitated by the formation of twin boundaries. 展开更多
关键词 Coarse-grain superplasticity Deformation mechanism Ni-Co-based superalloy Fracture mechanism Microstructure evolution
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Mechanisms of hydrated ion bridges in the development of low and ultra-low permeability reservoirs
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作者 JIN Xu CUI Fenglu +7 位作者 WU Yining WANG Xiaoqi MENG Siwei ZHANG Chenjun LIU Xiaodan TAO Jiaping SHEN Man WANG Fengchao 《Petroleum Exploration and Development》 2025年第5期1291-1300,共10页
This study focuses on the hydrated ion bridge(HIB)effect at the oil-rock interface in low-to ultra-low-permeability oil reservoirs.It systematically summarizes the research methodologies,formation mechanisms,interacti... This study focuses on the hydrated ion bridge(HIB)effect at the oil-rock interface in low-to ultra-low-permeability oil reservoirs.It systematically summarizes the research methodologies,formation mechanisms,interaction strength,and disruption mechanisms of HIB,and discusses the influencing mechanisms of HIB on the occurrence state and mobility of crude oil.On this basis,the key challenges inherent in the current HIB research are analyzed,and prospective directions for future development are proposed.Currently,research in this field primarily relies on experimental characterization techniques and molecular simulation methods.The microscopic interactions involved in HIB formation mainly include electrostatic interactions,hydrogen bonds and van der Waals forces.Notably,the hydrogen bonds between polar molecules in crude oil and hydrated ions serve as the primary sites for disrupting the HIB effect.The interaction strength of HIB is collectively modulated by ion type and concentration,reservoir solution environment,mineral type of reservoir rocks,and polar components in crude oil,which subsequently influence the occurrence state and mobility of crude oil.Systematic challenges persist in HIB-related research across three dimensions:research methodologies,scale integration and geological complexity.Specifically,the dynamic evolution mechanism of HIB remains inadequately elucidated;a discontinuity exists in the connection of spatiotemporal cross-scale modeling and prediction;and the reproducibility of actual geological environments in experimental settings is insufficient.Future research may pursue breakthroughs in the following three aspects:(1)developing in-situ dynamic experimental characterization techniques and machine learning-augmented simulation strategies;(2)establishing a framework for cross-scale model fusion and upscaling prediction;and(3)conducting in-depth studies on HIB under the coupled effects of complex mineral systems and multi-physical fields. 展开更多
关键词 low and ultra-low permeability reservoirs hydrated ion bridge formation mechanism interaction strength disruption mechanism oil displacement efficiency fluid-solid interface
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