期刊文献+
共找到478篇文章
< 1 2 24 >
每页显示 20 50 100
Strong metal-support interactions between highly dispersed Cu^(+) species and ceria via mix-MOF pyrolysis toward promoted water-gas shift reaction
1
作者 Xiao-Chen Sun Xing-Chi Li +7 位作者 Ze-Wei Xie Chen-Yue Yuan De-Jiu Wang Qian Zhang Xiao-Yu Guo Hao Dong Hai-Chao Liu Ya-Wen Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期475-483,共9页
The modulation of metal-support interfacial interaction is significant but challenging in the design of high-efficiency and high-stability supported catalysts.Here,we report a synthetic strategy to upgrade Cu-CeO_(2)i... The modulation of metal-support interfacial interaction is significant but challenging in the design of high-efficiency and high-stability supported catalysts.Here,we report a synthetic strategy to upgrade Cu-CeO_(2)interfacial interaction by the pyrolysis of mixed metal-organic framework(MOF)structure.The obtained highly dispersed Cu/CeO_(2)-MOF catalyst via this strategy was used to catalyze water-gas shift reaction(WGSR),which exhibited high activity of 40.5μmolCOgcat^(-1).s^(-1)at 300℃and high stability of about 120 h.Based on comprehensive studies of electronic structure,pyrolysis strategy has significant effect on enhancing metal-support interaction and then stabilizing interfacial Cu^(+)species under reaction conditions.Abundant Cu^(+)species and generated oxygen vacancies over Cu/CeO_(2)-MOF catalyst played a key role in CO molecule activation and H2O molecule dissociation,respectively.Both collaborated closely and then promoted WGSR catalytic performance in comparison with traditio nal supported catalysts.This study shall offer a robust approach to harvest highly dispersed catalysts with finely-tuned metal-support interactions for stabilizing the most interfacial active metal species in diverse heterogeneous catalytic reactions. 展开更多
关键词 Cu-based catalyst MOF derivative Water-gas shift reaction Metal-support interaction
下载PDF
Achieving asymmetric redox chemistry for oxygen evolution reaction through strong metal-support interactions
2
作者 Shihao Wang Meiling Fan +4 位作者 Hongfei Pan Jiahui Lyu Jinsong Wu Haolin Tang Haining Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期526-535,共10页
Water electrolysis poses a significant challenge for balancing catalytic activity and stability of oxygen evolution reaction(OER)electrocatalysts.In this study,we address this challenge by constructing asymmetric redo... Water electrolysis poses a significant challenge for balancing catalytic activity and stability of oxygen evolution reaction(OER)electrocatalysts.In this study,we address this challenge by constructing asymmetric redox chemistry through elaborate surface OO–Ru–OH and bulk Ru–O–Ni/Fe coordination moieties within single-atom Ru-decorated defective NiFe LDH nanosheets(Ru@d-NiFe LDH)in conjunction with strong metal-support interactions(SMSI).Rigorous spectroscopic characterization and theoretical calculations indicate that single-atom Ru can delocalize the O 2p electrons on the surface and optimize d-electron configurations of metal atoms in bulk through SMSI.The^(18)O isotope labeling experiment based on operando differential electrochemical mass spectrometry(DEMS),chemical probe experiments,and theoretical calculations confirm the encouraged surface lattice oxygen,stabilized bulk lattice oxygen,and enhanced adsorption of oxygen-containing intermediates for bulk metals in Ru@d-NiFe LDH,leading to asymmetric redox chemistry for OER.The Ru@d-NiFe LDH electrocatalyst exhibits exceptional performance with an overpotential of 230 mV to achieve 10 mA cm^(−2)and maintains high robustness under industrial current density.This approach for achieving asymmetric redox chemistry through SMSI presents a new avenue for developing high-performance electrocatalysts and instills confidence in its industrial applicability. 展开更多
关键词 reaction redox chemistry Strong metal-support interactions Layered double hydroxides ELECTROCATALYSTS Water electrolysis
下载PDF
Confined cobalt single-atom catalysts with strong electronic metal-support interactions based on a biomimetic self-assembly strategy
3
作者 Bowen Guo Zekun Wang +3 位作者 Lei Zheng Guang Mo Hongjun Zhou Dan Luo 《Carbon Energy》 SCIE EI CAS CSCD 2024年第9期156-171,共16页
Designing high-performance and low-cost electrocatalysts for oxygen evolu-tion reaction(OER)is critical for the conversion and storage of sustainable energy technologies.Inspired by the biomineralization process,we ut... Designing high-performance and low-cost electrocatalysts for oxygen evolu-tion reaction(OER)is critical for the conversion and storage of sustainable energy technologies.Inspired by the biomineralization process,we utilized the phosphorylation sites of collagen molecules to combine with cobalt-based mononuclear precursors at the molecular level and built a three-dimensional(3D)porous hierarchical material through a bottom-up biomimetic self-assembly strategy to obtain single-atom catalysts confined on carbonized biomimetic self-assembled carriers(Co SACs/cBSC)after subsequent high-temperature annealing.In this strategy,the biomolecule improved the anchoring efficiency of the metal precursor through precise functional groups;meanwhile,the binding-then-assembling strategy also effectively suppressed the nonspecific adsorption of metal ions,ultimately preventing atomic agglomeration and achieving strong electronic metal-support interactions(EMSIs).Experimental characterizations confirm that binding forms between cobalt metal and carbonized self-assembled substrate(Co–O_(4)–P).Theoretical calculations disclose that the local environment changes significantly tailored the Co d-band center,and optimized the binding energy of oxygenated intermediates and the energy barrier of oxygen release.As a result,the obtained Co SACs/cBSC catalyst can achieve remarkable OER activity and 24 h durability in 1 M KOH(η10 at 288 mV;Tafel slope of 44 mV dec-1),better than other transition metal-based catalysts and commercial IrO_(2).Overall,we presented a self-assembly strategy to prepare transition metal SACs with strong EMSIs,providing a new avenue for the preparation of efficient catalysts with fine atomic structures. 展开更多
关键词 biomimetic self-assembly support electronic metal-support interactions oxygen evolution reaction single atoms catalysts
下载PDF
Interactions between gas flow and reversible chemical reaction in porous media 被引量:1
4
作者 JIANG Yuan-yong XU Zeng-he +1 位作者 ZHANG Meng-zhou BAI Li-yuan 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第5期1144-1154,共11页
Taking into consideration the gas compressibility and chemical reaction reversibility, a model was developed to study the interactions between gas flow and chemical reaction in porous media and resolved by the finite ... Taking into consideration the gas compressibility and chemical reaction reversibility, a model was developed to study the interactions between gas flow and chemical reaction in porous media and resolved by the finite volume method on the basis of the gas-solid reaction aA(g)+bB(s)cC(g)+dD(s).The numerical analysis shows that the equilibrium constant is an important factor influencing the process of gas-solid reaction. The stoichiometric coefficients, molar masses of reactant gas, product gas and inert gas are the main factors influencing the density of gas mixture. The equilibrium constant influences the gas flow in porous media obviously when the stoichiometric coefficients satisfy a/c≠1. 展开更多
关键词 POROUS media COMPRESSIBLE gas flow REVERSIBLE chemical reaction interaction
下载PDF
Realizing optimal hydrogen evolution reaction properties via tuning phosphorous and transition metal interactions 被引量:3
5
作者 Haishun Jiang Siyu Zhao +5 位作者 Wenyao Li Tobias P.Neville Isil Akpinar Paul R.Shearing Dan J.L.Brett Guanjie He 《Green Energy & Environment》 SCIE CSCD 2020年第4期506-512,共7页
Hydrogen is one of the most attractive renewables for future energy application,therefore it is vital to develop cost-effective and highlyefficient electrocatalysts for the hydrogen evolution reaction(HER)to promote t... Hydrogen is one of the most attractive renewables for future energy application,therefore it is vital to develop cost-effective and highlyefficient electrocatalysts for the hydrogen evolution reaction(HER)to promote the generation of hydrogen from mild methods.In this work,Co–Mo phosphide nanosheets with the adjustable ratio of Co and Mo were fabricated on carbon cloth by a facile hydrothermal-annealing method.Owing to the unique nanostructures,abundant active surfaces and small resistance were achieved.Excellent electrocatalytic performances are obtained,such as the small overpotential of^67.3 mV to realize a current density of 10 mA cm^(-2) and a Tafel slope of 69.9 mV dec^(-1).Rapid recovery of the current response under multistep chronoamperometry is realized and excellent stability retained after the CV test for 2000 cycles.The change of electronic states of different elements was carefully studied which suggested the optimal electrochemical performance can be realized by tuning phosphorous and metal interactions. 展开更多
关键词 Co-Mo Phosphide NANOSHEETS Hydrogen evolution reaction Metal-phosphorous interactions
下载PDF
Revelation of bimolecular tautomerization induced by the concerted and radical interactions in lignin pyrolysis
6
作者 Wen-luan Xie Bin Hu +4 位作者 Wen-ming Zhang He-long Li Guo-yong Song Ji Liu Qiang Lu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第9期1-10,共10页
Bimolecular interactions play crucial roles in lignin pyrolysis.The tautomerization of key intermediates has a significant impact on the formation of stable products,whereas bimolecular tautomerization has been rarely... Bimolecular interactions play crucial roles in lignin pyrolysis.The tautomerization of key intermediates has a significant impact on the formation of stable products,whereas bimolecular tautomerization has been rarely clarified.In the present work,the bimolecular tautomerization mechanism induced by both concerted and radical interactions was proposed and carefully confirmed.A characteristicβ-O-4 lignin dimer,2-phenoxy-1-phenylethanol(α-OH-PPE),was used as the model compound to reveal two representative keto-phenol and enol-keto tautomerism mechanisms,based on theoretical calculations combined with pyrolysis experiments.The results indicate that the unimolecular tautomerism as the rate-determining step limits product generation,due to fairly high energy barriers.While the free hydroxy compounds and radicals derived from initial pyrolysis can further initiate bimolecular tautomerism reactions through the one-step concerted hydroxyl-assisted hydrogen transfer(hydroxylAHT)and two-step radical hydrogen abstraction interactions,respectively.By alleviating and even avoiding the large ring tension of tautomerism,the unstable tautomers(2,4-cyclohexadienone and1-hydroxy styrene)can be rapidly tautomerized into stable phenol and acetophenone with the help of intermolecular interaction.Benefitting from the significant advantage of retro-ene fragmentation in breaking theβ-O-4 bond to form tautomers,a large amount of stable phenolic and ketone products can be generated following bimolecular tautomerization in the pyrolysis ofβ-O-4 linked lignin. 展开更多
关键词 Lignin pyrolysis interaction mechanism TAUTOMERISM Hydroxyl-assisted hydrogen transfer Radical chain reaction
下载PDF
Reaction视频中用户弹幕信息交互行为的情感反应生成机理研究
7
作者 叶许婕 赵宇翔 +2 位作者 张妍 李金昊 Preben Hansen 《信息资源管理学报》 2024年第2期104-120,共17页
深入挖掘Reaction视频中弹幕信息交互行为的情感反应机理有助于理解用户弹幕创作背后的情感生成原因及情感变化过程。本文基于情感反应模型,利用定向内容分析法对哔哩哔哩网站中11个热门视频的弹幕信息资源、视频内容以及reactor反应情... 深入挖掘Reaction视频中弹幕信息交互行为的情感反应机理有助于理解用户弹幕创作背后的情感生成原因及情感变化过程。本文基于情感反应模型,利用定向内容分析法对哔哩哔哩网站中11个热门视频的弹幕信息资源、视频内容以及reactor反应情况展开编码研究,构建了Reaction视频中用户弹幕信息交互行为的情感反应生成机理模型。研究发现,Reaction视频弹幕信息交互行为中的情感反应生成机理总体上遵循“信息刺激-情感反应”的路径,信息刺激有时会独立唤醒情绪或特定情感态度,有时也会通过唤醒特定情感态度进而影响情绪或内化情感态度的生成。该模型有助于提升情感反应理论在计算机协助交流中的情境化探索,也将为社交媒体中用户与信息交互提供优化建议。 展开更多
关键词 reaction视频 弹幕 用户信息交互 情感反应模型 定向内容分析
下载PDF
Strong metal–support interaction boosts the electrocatalytic hydrogen evolution capability of Ru nanoparticles supported on titanium nitride
8
作者 Xin Wang Xiaoli Yang +7 位作者 Guangxian Pei Jifa Yang Junzhe Liu Fengwang Zhao Fayi Jin Wei Jiang Haoxi Ben Lixue Zhang 《Carbon Energy》 SCIE EI CAS CSCD 2024年第1期245-254,共10页
Ruthenium(Ru)has been regarded as one of the most promising alternatives to substitute Pt for catalyzing alkaline hydrogen evolution reaction(HER),owing to its inherent high activity and being the cheapest platinum-gr... Ruthenium(Ru)has been regarded as one of the most promising alternatives to substitute Pt for catalyzing alkaline hydrogen evolution reaction(HER),owing to its inherent high activity and being the cheapest platinum-group metal.Herein,based on the idea of strong metal–support interaction(SMSI)regulation,Ru/TiN catalysts with different degrees of TiN overlayer over Ru nanoparticles were fabricated,which were applied to the alkaline electrolytic water.Characterizations reveal that the TiN overlayer would gradually encapsulate the Ru nanoparticles and induce more electron transfer from Ru nanoparticles to TiN support by the Ru–N–Ti bond as the SMSI degree increased.Further study shows that the exposed Ru–TiN interfaces greatly promote the H_(2) desorption capacity.Thus,the Ru/TiN-300 with a moderate SMSI degree exhibits excellent HER performance,with an overpotential of 38 mV at 10 mA cm^(−2).Also,due to the encapsulation role of TiN overlayer on Ru nanoparticles,it displays super long-term stability with a very slight potential change after 24 h.This study provides a deep insight into the influence of the SMSI effect between Ru and TiN on HER and offers a novel approach for preparing efficient and stable HER electrocatalysts through SMSI engineering. 展开更多
关键词 electronic structure hydrogen evolution reaction RUTHENIUM strong metal-support interaction titanium nitride
下载PDF
van der Waals Interactions in Bimolecular Reactions
9
作者 Jian-wei Cao Feng-yi Li +1 位作者 Wen-sha Xia Wen-sheng Bian 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2019年第2期157-166,I0002,共11页
The van der Waals (vdW) interaction is very important in fields of physics, biology and chemistry, and its role in reaction dynamics is an issue of great interest. In this review, we focus on the recent progresses in ... The van der Waals (vdW) interaction is very important in fields of physics, biology and chemistry, and its role in reaction dynamics is an issue of great interest. In this review, we focus on the recent progresses in the theoretical and experimental studies on the vdW interaction in bimolecular reactions. In particular, we review those studies that have advanced our understanding of how the vdW interaction can strongly influence the dynamics in both direct activated and complex-forming reactions, and further extend the discussion to the polyatomic reactions involving more atoms and those occurring at cold and ultracold temperatures. We indicate that an accurate description of the delicate vdW structure and long-range potential remains a challenge nowadays in either ab initio calculations or the fitting of the potential energy surfaces. We also present an explanation on the concept of vdW saddle proposed by us recently which may have general importance. 展开更多
关键词 van der Waals interaction Complex-forming reactions reaction mechanisms Ultracold chemical reactions Ab initio potential energy surfaces
下载PDF
Improving the electrocatalytic performances of Pt-based catalysts for oxygen reduction reaction via strong interactions with single-CoN_(4)-rich carbon support
10
作者 Jin Long Xingqun Zheng +3 位作者 Bin Wang Chenzhong Wu Qingmei Wang Lishan Peng 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第5期265-271,共7页
Developing platinum-group-metal(PGM)catalysts possessing strong metal-support interaction and controllable PGM size is urgent for the sluggish oxygen reduction reaction(ORR)in proton-exchange membrane fuel cells.Herei... Developing platinum-group-metal(PGM)catalysts possessing strong metal-support interaction and controllable PGM size is urgent for the sluggish oxygen reduction reaction(ORR)in proton-exchange membrane fuel cells.Herein,we propose an in-situ self-assembled reduction strategy to successfully induce highly-dispersed sub-3nm platinum nanoparticles(Pt NPs)to attach on resin-derived atomic Co coordinated by N-doped carbon substrate(Pt/Co_(SA)-N-C)for ORR.To be specific,the interfacial electron interaction effect,along with a highly robust Co_(SA)-N-C support endow the as-fabricated Pt/Co_(SA)-N-C catalyst with significantly enhanced catalytic properties,i.e.,a mass activity(MA)of 0.719 A/mgPt at 0.9 ViR-free and a reduction of 24.2%in MA after a 20,000-cycles test.Density functional theory(DFT)calculations demonstrate that the enhanced electron interaction between Pt and Co_(SA)-N-C support decreases the dband center of Pt,which is in favor of lowering the desorption energy of ^(*)OH on Pt/Co_(SA)-N-C surface and accelerating the formation of H_(2)O,thus enhance the instinct activity of ORR.Furthermore,the higher binding energy between Pt and Co_(SA)-N-C compared to Pt and C indicates that the migration of Pt has been suppressed,which theoretically explains the improved durability of Pt/Co_(SA)-N-C.Our work offers an enlightenment on constructing composite Pt-based catalysts with multiple active sites. 展开更多
关键词 Fuel cells Oxygen reduction reaction PLATINUM Single-CoN_(4)-rich carbon support Metal-substrate interaction
原文传递
Dry Reforming of Ethane over FeNi/Al-Ce-O Catalysts:Composition-Induced Strong Metal-Support Interactions
11
作者 Tao Zhang Zhi-Cheng Liu +4 位作者 Ying-Chun Ye Yu Wang He-Qin Yang Huan-Xin Gao Wei-Min Yang 《Engineering》 SCIE EI CAS 2022年第11期173-185,共13页
Dry reforming of ethane(DRE)has received significant attention because of its potential to produce chemical raw materials and reduce carbon emissions.Herein,a composition-induced strong metal-support interaction(SMSI)... Dry reforming of ethane(DRE)has received significant attention because of its potential to produce chemical raw materials and reduce carbon emissions.Herein,a composition-induced strong metal-support interaction(SMSI)effect over FeNi/Al-Ce-O catalysts is revealed via X-ray photoelectron spectroscopy(XPS),H_(2)-temperature programmed reduction(TPR),and energy dispersive X-ray spectroscopy(EDS)elemental mapping.The introduction of Al into Al-Ce-O supports significantly influences the dispersion of surface active components and improves the catalytic performance for DRE over supported FeNi catalysts due to enhancement of the SMSI effect.The catalytic properties,for example,C_(2)H_(6) and CO_(2) conversion,CO selectivity and yield,and turnover frequencies(TOFs),of supported FeNi catalysts first increase and then decrease with increasing Al content,following the same trend as the theoretical effective surface area(TESA)of the corresponding catalysts.The FeNi/Ce-Al_(0.5) catalyst,with 50%Al content,exhibits the best DRE performance under steady-state conditions at 873 K.As observed by with in situ Fourier transform infrared spectroscopy(FTIR)analysis,the introduction of Al not only increases the content of surface Ce3+and oxygen vacancies but also promotes the dispersion of surface active components,which further alters the catalytic properties for DRE over supported FeNi catalysts. 展开更多
关键词 Dry reforming of ethane Strong metal-support interaction Carbon dioxide CERIA Oxygen vacancy reaction mechanism
下载PDF
In situ confined vertical growth of Co_(2.5)Ni_(0.5)Si_(2)O_(5)(OH)_(4)nanoarrays on rGO for an efficient oxygen evolution reaction 被引量:1
12
作者 Yang Mu Xiaoyu Pei +5 位作者 Yunfeng Zhao Xueying Dong Zongkui Kou Miao Cui Changgong Meng Yifu Zhang 《Nano Materials Science》 EI CAS CSCD 2023年第4期351-360,共10页
Rational design of oxygen evolution reaction(OER)catalysts at low cost would greatly benefit the economy.Taking advantage of earth-abundant elements Si,Co and Ni,we produce a unique-structure where cobalt-nickel silic... Rational design of oxygen evolution reaction(OER)catalysts at low cost would greatly benefit the economy.Taking advantage of earth-abundant elements Si,Co and Ni,we produce a unique-structure where cobalt-nickel silicate hydroxide[Co_(2.5)Ni_(0.5)Si_(2)O_(5)(OH)_(4)]is vertically grown on a reduced graphene oxide(rGO)support(CNS@rGO).This is developed as a low-cost and prospective OER catalyst.Compared to cobalt or nickel silicate hydroxide@rGO(CS@rGO and NS@rGO,respectively)nanoarrays,the bimetal CNS@rGO nanoarray exhibits impressive OER performance with an overpotential of 307 mV@10 mA cm^(-2).This value is higher than that of CS@rGO and NS@rGO.The CNS@rGO nanoarray has an overpotential of 446 mV@100 mA cm^(-2),about 1.4 times that of the commercial RuO_(2)electrocatalyst.The achieved OER activity is superior to the state-of-the-art metal oxides/hydroxides and their derivatives.The vertically grown nanostructure and optimized metal-support electronic interactions play an indispensable role for OER performance improvement,including a fast electron transfer pathway,short proton/electron diffusion distance,more active metal centers,as well as optimized dualatomic electron density.Taking advantage of interlay chemical regulation and the in-situ growth method,the advanced-structural CNS@rGO nanoarrays provide a new horizon to the rational and flexible design of efficient and promising OER electrocatalysts. 展开更多
关键词 Co_(2.5)Ni_(0.5)Si_(2)O_(5)(OH)_(4)@rGO Vertical grown nanoarrays Geometric and electronic structure regulation Metal-support interactions Oxygen evolution reaction
下载PDF
Tuning the charge distribution and crystal field of iron single atoms via iron oxide integration for enhanced oxygen reduction reaction in zinc-air batteries
13
作者 Feifei Zhang Yinlong Zhu +9 位作者 Yijun Zhong Jing Zou Yu Chen Lianhai Zu Zhouyou Wang Jack Jon Hinsch Yun Wang Lian Zhang Zongping Shao Huanting Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第10期154-163,I0006,共11页
Metal-air batteries face a great challenge in developing efficient and durable low-cost oxygen reduction reaction(ORR)electrocatalysts.Single-atom iron catalysts embedded into nitrogen doped carbon(Fe-N-C)have emerged... Metal-air batteries face a great challenge in developing efficient and durable low-cost oxygen reduction reaction(ORR)electrocatalysts.Single-atom iron catalysts embedded into nitrogen doped carbon(Fe-N-C)have emerged as attractive materials for potential replacement of Pt in ORR,but their catalytic performance was limited by the symmetrical electronic structure distribution around the single-atom Fe site.Here,we report our findings in significantly enhancing the ORR performance of Fe-N-C by moderate Fe_(2)O_(3) integration via the strong electronic interaction.Remarkably,the optimized catalyst(M-Fe_(2)O_(3)/Fe_(SA)@NC)exhibits excellent activity,durability and good tolerance to methanol,outperforming the benchmark Pt/C catalyst.When M-Fe_(2)O_(3)/Fe_(SA)@NC catalyst was used in a practical zinc-air battery assembly,peak power density of 155 mW cm^(-2)and specific capacity of 762 mA h g_(Zn)^(-1)were achieved and the battery assembly has shown superior cycling stability over a period of 200 h.More importantly,theoretical studies suggest that the introduction of Fe_(2)O_(3) can evoke the crystal field alteration and electron redistribution on single Fe atoms,which can break the symmetric charge distribution of Fe-N_(4) and thereby optimize the corresponding adsorption energy of intermediates to promote the O_(2)reduction.This study provides a new pathway to promote the catalytic performance of single-atom catalysts. 展开更多
关键词 Single-atom catalysts Oxide nanoclusters Electronic interactions Oxygen reduction reaction Zn-air battery
下载PDF
猪肺炎支原体通过抑制SPLUNC1功能破坏呼吸道炎性反应平衡
14
作者 王海燕 张珍珍 +2 位作者 倪博 刘蓓蓓 冯志新 《中国农业科学》 CAS CSCD 北大核心 2024年第1期216-226,共11页
【背景】猪肺炎支原体(Mycoplasmahyopneumoniae,Mhp)通过定植猪呼吸道黏膜层,破坏呼吸道炎性反应平衡,引起炎性损伤和持续性感染。短的上腭、肺及鼻咽上皮克隆1蛋白(short palate lung and nasal epithelial clone1,SPLUNC1)是呼吸道... 【背景】猪肺炎支原体(Mycoplasmahyopneumoniae,Mhp)通过定植猪呼吸道黏膜层,破坏呼吸道炎性反应平衡,引起炎性损伤和持续性感染。短的上腭、肺及鼻咽上皮克隆1蛋白(short palate lung and nasal epithelial clone1,SPLUNC1)是呼吸道黏膜分泌的具有重要抗菌和抗炎功能的蛋白,被认为是呼吸道黏膜面对危险信号时的“信号传感器”。【目的】从Mhp和SPLUNC1相互作用入手,分析Mhp感染对SPLUNC1表达的影响以及SPLUNC1对Mhp引起的炎性反应的调控作用,揭示Mhp引起炎性损伤的新机制,为解决Mhp持续性感染问题提供参考。【方法】利用猪肺炎支原体对猪支气管上皮细胞(porcine bronchial epithelial cells,PBECs)感染模型和猪体感染模型,通过荧光定量PCR、间接免疫荧光和Western-blotting等方法,分别检测Mhp感染后对肺脏中SPLUNC1以及体外PBECs中SPLUNC1转录和表达的影响。克隆并扩增猪源SPLUNC1基因通过酶切鉴定,构建成功SPLUNC1真核和原核表达重组质粒pCDNA3.1-SPLUNC1以及pET28a-SPLUNC1。与此同时,设计靶向SPLUNC1的siRNA干扰片段。利用体外SPLUNC1蛋白孵育、体内呼吸道黏膜SPLUNC1抗体封闭,通过Mhp CCU50检测明确SPLUNC1对Mhp体内外生长的影响。在猪支气管上皮细胞中,通过过表达或siRNA干扰SPLUNC1基因,后感染Mhp,利用Western-blotting、间接免疫荧光以及酶联免疫吸附方法,明确SPLUNC1对Mhp的黏附作用、诱导炎性因子表达以及MAPK信号通路活化的影响。【结果】Mhp感染猪后可引起肺脏实变,主要组织病理表现为肺脏炎性损伤,同时显著上调肺泡灌洗液中趋化因子CXCL8和炎性因子TNFα和IL-1β分泌。Mhp体内外感染后,体内肺脏和体外猪支气管上皮细胞中SPLUNC1的转录和表达均显著下调。以上研究表明,Mhp可诱导肺脏炎性反应,抑制SPLUNC1表达。另一方面,体外PBECs中过表达SPLUNC1后,Mhp感染引起的CXCL8表达显著减少;siRNA干扰SPLUNC1后,Mhp感染引起的CXCL8表达显著增加,表明SPLUNC1负调控Mhp感染引起的CXCL8表达。基于Mhp感染入侵呼吸道过程,本研究进一步解析SPLUNC1负调控CXCL8表达的机制。结果表明:无论是SPLUNC1和Mhp体外孵育,还是SPLUNC1抗体体内封闭,Mhp的体内外生长均未受影响;SPLUNC1的过表达或siRNA干扰对Mhp体外黏附PBECs的能力也无显著影响;过表达SPLUNC1可抑制pERK和IκBα的激活,相反SPLUNC1 siRNA干扰后,可促进pERK和IκBα的激活。以上研究证明SPLUNC1不是通过调控Mhp的生长和黏附,而是通过负调控MAPK-ERK通路的活化来调控CXCL8的表达。【结论】SPLUNC1可通过MAPK-ERK信号通路来调控炎性因子的过度表达,维护宿主炎性平衡;与此同时,Mhp感染后可通过抑制SPLUNC1的表达来破坏宿主炎性反应的平衡调控,进而引起炎性损伤。本研究为解析Mhp感染损伤机制提供依据。 展开更多
关键词 猪肺炎支原体 支原体-宿主相互作用 炎性反应 SPLUNC1
下载PDF
伏诺拉生不良反应研究进展
15
作者 姜立根 卢增珍 +1 位作者 杨柳 刘华一 《实用药物与临床》 CAS 2024年第4期297-303,共7页
伏诺拉生是新型的抑酸药物,药理作用与质子泵抑制剂不同,抑酸作用较质子泵抑制剂可能更为强大、持久。随着伏诺拉生临床应用时间和病例数的增加,不良反应报道也逐渐增多,同时随着临床药理研究的深入,伏诺拉生潜在的不良反应也逐渐呈现... 伏诺拉生是新型的抑酸药物,药理作用与质子泵抑制剂不同,抑酸作用较质子泵抑制剂可能更为强大、持久。随着伏诺拉生临床应用时间和病例数的增加,不良反应报道也逐渐增多,同时随着临床药理研究的深入,伏诺拉生潜在的不良反应也逐渐呈现。本文通过检索文献,了解伏诺拉生抑酸作用导致的潜在不良反应,以及伏诺拉生与其他药物联合应用时可能出现的潜在不良反应。 展开更多
关键词 伏诺拉生 药物不良反应 抑酸作用 药物相互作用
下载PDF
嵌岩桩水平承载力地基反力Matlock法分析
16
作者 赵学亮 李宇 +3 位作者 黄钺 田伟辉 王洪庆 何润财 《科学技术与工程》 北大核心 2024年第1期320-326,共7页
嵌岩桩在海上风电、跨海大桥等结构中的应用十分广泛,但在嵌岩桩水平承载特性方面的研究仍有较多不足。弹性地基反力法中的Matlock法在中国是用于计算水平承载桩承载力时应用最多的方法,但地基反力Matlock法针对嵌岩桩缺少合理的取值方... 嵌岩桩在海上风电、跨海大桥等结构中的应用十分广泛,但在嵌岩桩水平承载特性方面的研究仍有较多不足。弹性地基反力法中的Matlock法在中国是用于计算水平承载桩承载力时应用最多的方法,但地基反力Matlock法针对嵌岩桩缺少合理的取值方法。基于现场试验数据建立并验证有限差分数值模型,通过数值模拟与参数分析,研究了岩体力学参数和桩基参数等因素对桩岩相互作用的影响,提出了Matlock法中地基反力系数比例系数的拟合计算公式。通过现场试验数据对提出的方法进行了验证,结果表明计算结果与实际情况较为相符,与其他方法比较,所提出的修正Matlock法相对非线性的p-y曲线法具有取值计算较为简便的优势。 展开更多
关键词 嵌岩桩 水平承载力 数值分析 地基反力Matlock法 变形特征 桩岩相互作用
下载PDF
钨掺杂镍铁水滑石高效电催化析氧反应 被引量:1
17
作者 段欣漩 Marshet Getaye Sendeku +6 位作者 张道明 周道金 徐立军 高学庆 陈爱兵 邝允 孙晓明 《物理化学学报》 SCIE CAS CSCD 北大核心 2024年第1期44-45,共2页
电解水对制备可持续和清洁的氢气能源至关重要。电解水的阳极析氧反应设计复杂的4-电子转移过程,所需能耗较高,是电解水的速控步骤。催化剂对于析氧反应的进行具有重要作用。镍铁水滑石是最具潜力的碱性非贵金属析氧反应(OER)催化剂,但... 电解水对制备可持续和清洁的氢气能源至关重要。电解水的阳极析氧反应设计复杂的4-电子转移过程,所需能耗较高,是电解水的速控步骤。催化剂对于析氧反应的进行具有重要作用。镍铁水滑石是最具潜力的碱性非贵金属析氧反应(OER)催化剂,但是由于水滑石导电性差、活性位点暴露不充分、对反应中间体吸附较弱等问题,催化活性还需要进一步提高。如何提升催化活性已经被科学家们广泛关注,比如:制造缺陷、掺杂、将水滑石剥离为单层结构和组装为阵列结构等。在本论文中,通过简单的“一锅法”醇解合成了一系列不同量W掺杂NiFe-LDH的样品。XRD结果表明合成的NiFeW-LDH的衍射峰与完美NiFe-LDH标准卡片相同,没有其他的衍射峰,表明W没有单独成相,被成功掺杂进入NiFe-LDH。扫描电镜表明NiFeW-LDH为纳米片(尺寸约为~500 nm)组成的3d立体花状结构,且材料中Ni、Fe和W均匀分布。XPS表明材料中W的价态为6+,与未掺杂的NiFe-LDH相比,Fe向高价态移动,表面吸附的OH增多。在密度泛函理论(DFT)计算中,结果同样表明W6+掺杂有利于H2O和O*中间体的吸附,提高了Fe位点的活性。在1 mol∙L^(−1) KOH中,NiFeW-LDH达到10 mA·cm^(−2)所需过电位是199和237 mV,这比大多数的NiFe基粉末催化剂的性能好。综上,实验和计算表明W掺杂调控催化剂中Fe位点电子结构,优化对反应中间体的吸附,使催化剂具有更高活性。 展开更多
关键词 析氧反应 水滑石 钨掺杂 电子相互作用 电催化
下载PDF
Valence electronic engineering of superhydrophilic Dy-evoked Ni-MOF outperforming RuO_(2) for highly efficient electrocatalytic oxygen evolution 被引量:1
18
作者 Zhiyang Huang Miao Liao +6 位作者 Shifan Zhang Lixia Wang Mingcheng Gao Zuyang Luo Tayirjan Taylor Isimjan Bao Wang Xiulin Yang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期244-252,I0007,共10页
Tackling the problem of poor conductivity and catalytic stability of pristine metal-organic frameworks(MOFs) is crucial to improve their oxygen evolution reaction(OER) performance.Herein,we introduce a novel strategy ... Tackling the problem of poor conductivity and catalytic stability of pristine metal-organic frameworks(MOFs) is crucial to improve their oxygen evolution reaction(OER) performance.Herein,we introduce a novel strategy of dysprosium(Dy) doping,using the unique 4f orbitals of this rare earth element to enhance electrocatalytic activity of MOFs.Our method involves constructing Dy-doped Ni-MOF(Dy@Ni-MOF) nanoneedles on carbon cloth via a Dy-induced valence electronic perturbation approach.Experiments and density functional theory(DFT) calculations reveal that Dy doping can effectively modify the electronic structure of the Ni active centers and foster a strong electronic interaction between Ni and Dy.The resulting benefits include a reduced work function and a closer proximity of the d-band center to the Fermi level,which is conducive to improving electrical conductivity and promoting the adsorption of oxygen-containing intermediates.Furthermore,the Dy@Ni-MOF achieves superhydrophilicity,ensuring effective electrolyte contact and thus accelerating reaction kinetics,Ex-situ and in-situ analysis results manifest Dy_(2)O_(3)/NiOOH as the actual active species.Therefore,Dy@Ni-MOF shows impressive OER performance,significantly surpassing Ni-MOF.Besides,the overall water splitting device with Dy@NiMOF as an anode delivers a low cell voltage of 1.51 V at 10 mA cm^(-2) and demonstrates long-term stability for 100 h,positioning it as a promising substitute for precious metal catalysts. 展开更多
关键词 Dy@Ni-MOF Dy incorporation Electronic interaction SUPERHYDROPHILICITY Oxygen evolution reaction
下载PDF
Optimization and control of synchrotron emission in ultraintense laser–solid interactions using machine learning – CORRIGENDUM 被引量:1
19
作者 J.Goodman M.King +3 位作者 E.J.Dolier R.Wilson R.J.Gray P.McKenna 《High Power Laser Science and Engineering》 SCIE CAS CSCD 2024年第1期116-116,共1页
Due to an isolated error in the 3D simulation parameters,the laser energy and intensity(calculated using the energy)values were incorrectly stated as 10.9 J and 3×10^(22) W cm^(−2),respectively,in Sections 3.3,7 ... Due to an isolated error in the 3D simulation parameters,the laser energy and intensity(calculated using the energy)values were incorrectly stated as 10.9 J and 3×10^(22) W cm^(−2),respectively,in Sections 3.3,7 and 8.The correct values are 39.8 J and 1.1×10^(23) W cm^(−2).Similarly,the values stated for the higher energy case,109 J and 3×10^(23) W cm^(−2) in Section 7,should be 398 J and 1.1×10^(24) W cm^(−2),respectively. 展开更多
关键词 Bayesian optimization gamma rays laser-solid interactions machine learning radiation reaction
原文传递
基于交互反应优化高球比炉料结构的研究及应用
20
作者 董相娟 滕召杰 +2 位作者 武建龙 陈建 郑凯 《炼铁》 CAS 北大核心 2024年第1期59-62,共4页
不同炉料之间存在着交互反应,采用熔滴性能试验,对京唐高炉高球比条件下的合理炉料结构进行了研究。结果表明,不同炉料搭配后软化性能和熔滴性能有明显差异:烧结矿与酸性球团矿、碱性球团矿搭配的炉料结构性能最优;烧结矿与碱性球团矿... 不同炉料之间存在着交互反应,采用熔滴性能试验,对京唐高炉高球比条件下的合理炉料结构进行了研究。结果表明,不同炉料搭配后软化性能和熔滴性能有明显差异:烧结矿与酸性球团矿、碱性球团矿搭配的炉料结构性能最优;烧结矿与碱性球团矿搭配的炉料结构性能居中;而烧结矿搭配酸性球团矿并配石灰石的的炉料结构性能较差。2019-2021年,京唐3座5500m^(3)高炉采用优化后的高球比炉料结构,球团矿比例达50%以上,其中3号高炉月均球团矿比例最高达到65%,3座高炉长期稳定顺行,主要技术经济指标持续提升。 展开更多
关键词 特大型高炉 球团矿 烧结矿 交互反应 软化性能 炉料结构
下载PDF
上一页 1 2 24 下一页 到第
使用帮助 返回顶部