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基于“反应点针灸”理论针刺治疗中风后吞咽障碍的临床疗效研究 被引量:1
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作者 刘国强 陈巧巧 《大医生》 2023年第24期110-113,共4页
目的研究基于“反应点针灸”理论针刺治疗中风后吞咽障碍的临床效果。方法选取2022年5月至12月重庆市长寿区中医院收治的60例中风后吞咽障碍患者,采用随机数字表法分为对照组和观察组,各30例。两组患者均采取常规治疗,对照组实施普通针... 目的研究基于“反应点针灸”理论针刺治疗中风后吞咽障碍的临床效果。方法选取2022年5月至12月重庆市长寿区中医院收治的60例中风后吞咽障碍患者,采用随机数字表法分为对照组和观察组,各30例。两组患者均采取常规治疗,对照组实施普通针刺,观察组实施基于“反应点针灸”理论针刺治疗。比较两组患者的治疗前后洼田氏饮水试验评价量表评分;治疗前后白蛋白水平、血红蛋白水平;治疗前后焦虑、抑郁评分;治疗总有效率;治疗前后的生活质量评分;不良事件发生情况。结果治疗后,两组患者洼田氏饮水试验评价量表评分均降低,白蛋白、血红蛋白水平均升高,且观察组变化幅度均大于对照组(均P<0.05)。治疗后,两组患者焦虑、抑郁评分均降低,且观察组均低于对照组(均P<0.05)。观察组治疗总有效率高于对照组(P<0.05)。治疗后,两组患者各项生活质量评分均升高,且观察组均高于对照组(均P<0.05)。观察组患者不良反应总发生率低于对照组(P<0.05)。结论中风后吞咽障碍患者通过基于“反应点针灸”理论针刺治疗,可进一步促使患者康复,改善其负面情绪,提升生活质量,预防不良事件的发生,值得临床应用。 展开更多
关键词 基于“反应点针灸”理论针刺 中风 吞咽障碍 临床效果
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“冲击——反应”,还是“挑战——应战”?
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作者 许敏球 《视听界》 2019年第3期128-128,共1页
关于不同文明之间的碰撞,有两个有意思的观点。一个是美国学者费正清提出的“冲击—反应”理论模式。他认为中国由传统社会向近代社会的转型,是古老的中华文明受现代的西方文明“冲击”之后作出的“反应”,变革的动因来自外界刺激,而非... 关于不同文明之间的碰撞,有两个有意思的观点。一个是美国学者费正清提出的“冲击—反应”理论模式。他认为中国由传统社会向近代社会的转型,是古老的中华文明受现代的西方文明“冲击”之后作出的“反应”,变革的动因来自外界刺激,而非内生推动。另一个则是英国学者汤因比提出的“挑战—应战”理论模式。他认为文明的兴起是一连串的“挑战”与“应战”的过程。一个文明会遭遇到来自自然环境、人为环境,包括其他文明的种种挑战,只有成功地进行应战,解决了挑战提出的问题,这一文明才会生长和存续下去。挑战是外因,能否主动地、创造性地应战才是决定性的因素。 展开更多
关键词 “反应” 应战 西方文明 美国学者 近代社会 自然环境 中华文明 费正清
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Recent Advances on Ruthenium-based Electrocatalysts for Lithium-oxygen Batteries
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作者 Yu-Zhe Wang Zhuo-Liang Jiang +2 位作者 Bo Wen Yao-Hui Huang Fu-Jun Li 《电化学(中英文)》 CAS 北大核心 2024年第8期1-16,共16页
Rechargeable lithium-oxygen(Li-O_(2))batteries have attracted wide attention due to their high energy density.However,the sluggish cathode kinetics results in high overvoltage and poor cycling performance.Ruthenium(Ru... Rechargeable lithium-oxygen(Li-O_(2))batteries have attracted wide attention due to their high energy density.However,the sluggish cathode kinetics results in high overvoltage and poor cycling performance.Ruthenium(Ru)-based electrocatalysts have been demonstrated to be promising cathode catalysts to promote oxygen evolution reaction(OER).It facilitates decomposition of lithium peroxide(Li_(2)O_(2))by adjusting Li_(2)O_(2) morphologies,which is due to the strong interaction between Ru-based catalyst and superoxide anion(O_(2))intermediate.In this review,the design strategies of Ru-based electrocatalysts are introduced to enhance their OER catalytic kinetics in Li-O_(2) batteries.Different configurations of Ru-based catalysts,including metal particles(Ru metal and alloys),single-atom catalysts,and Ru-loaded compounds with various substrates(carbon materials,metal oxides/sulfides),have been summarized to regulate the electronic structure and the matrix architecture of the Ru-based electrocatalysts.The structure-property relationship of Ru-based catalysts is discussed for a better understanding of the Li_(2)O_(2) decomposition mechanism at the cathode interface.Finally,the challenges of Ru-based electrocatalysts are proposed for the future development of Li-O_(2) batteries. 展开更多
关键词 Lithium-oxygen battery Ruthenium-based electrocatalyst Reaction mechanism Reaction kinetics OVERVOLTAGE
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Calcium titanate corrosion inhibitor enabling carbon as inert anode for oxygen evolution in molten chlorides
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作者 Kai-fa DU Wen-miao LI +6 位作者 Pei-lin WANG Lei GUO Di CHEN Yong-song MA Rui YU Hua-yi YIN Di-hua WANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第10期3400-3411,共12页
The corrosion inhibition efficacy of titanate(CaTiO_(3))for carbon anodes in molten salts was investigated through various analytical techniques,including linear sweep voltammetry,X-ray diffraction,scanning electron m... The corrosion inhibition efficacy of titanate(CaTiO_(3))for carbon anodes in molten salts was investigated through various analytical techniques,including linear sweep voltammetry,X-ray diffraction,scanning electron microscopy,and energy dispersion spectroscopy.The results demonstrate that the addition of CaTiO_(3)corrosion inhibitor efficiently passivates the carbon anode and leads to the formation of a dense CaTiO_(3)layer during the electrolysis process in molten CaCl_(2)-CaO.Subsequently,the passivated carbon anode effectively undergoes the oxygen evolution reaction,with an optimal current density for passivation identified at 400 m A/cm~2.Comprehensive investigations,including CaTiO_(3)solubility tests in molten CaCl_(2)-CaO and numerical modeling of the stability of complex ionic structures,provide compelling evidence supporting“complexation-precipitation”passivation mechanism.This mechanism involves the initial formation of a complex containing TiO_(2)·nCaO by CaTiO_(3)and CaO,which subsequently decomposes to yield CaTiO_(3),firmly coating the surface of the carbon anode.In practical applications,the integration of CaTiO_(3)corrosion inhibitor with the carbon anode leads to the successful preparation of the FeCoNiCrMn high-entropy alloy without carbon contamination in the molten CaCl_(2)-Ca O. 展开更多
关键词 corrosion inhibitor calcium titanate carbon anode oxygen evolution reaction
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Syntheses and catalytic performances of three coordination polymers with tetracarboxylate ligands
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作者 MEI Zhenzhong WANG Hongyu +2 位作者 KANG Xiuqi SHAO Yongliang GU Jinzhong 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第9期1795-1802,共8页
Three zincand cobaltcoordination polymers,namely{[Zn_(2)(μ_(6)-adip)(phen)_(2)]·4H_(2)O}_(n)(1),{[Co_(2)(μ_(6)-adip)(bipy)_(2)]·4H_(2)O}_(n)(2),and[Co_(2)(μ4-adip)(μ-bpa)_(2)]_(n)(3)have been constructed... Three zincand cobaltcoordination polymers,namely{[Zn_(2)(μ_(6)-adip)(phen)_(2)]·4H_(2)O}_(n)(1),{[Co_(2)(μ_(6)-adip)(bipy)_(2)]·4H_(2)O}_(n)(2),and[Co_(2)(μ4-adip)(μ-bpa)_(2)]_(n)(3)have been constructed hydrothermally using H4adip(H4adip=5,5′-azanediyldiisophthalic acid),phen(phen=1,10-phenanthroline),bipy(bipy=2,2′-bipyridine),bpa(bpa=bis(4-pyridyl)amine),and zinc and cobalt chlorides at 160℃.The products were isolated as stable crystalline solids and were characterized by IR spectra,elemental analyses,thermogravimetric analyses,and single-crystal X-ray diffrac-tion analyses.Single-crystal X-ray diffraction analyses revealed that three compounds crystallize in the orthorhom-bic system Pnna(1 and 2)or P21212(3)space groups.All compounds exhibit 3D frameworks.The catalytic perfor-mances in the Henry reaction of these compounds were investigated.Compound 3 exhibited an effective catalytic activity in the Henry reaction at 70℃.CCDC:2339391,1;2339392,2;2339393,3. 展开更多
关键词 coordination polymer tetracarboxylic acid catalytic properties Henry reaction
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Microstructure and Oxidation Behavior of ZrB_(2)-SiC Ceramics Fabricated by Tape Casting and Reactive Melt Infiltration
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作者 TAN Min CHEN Xiaowu +5 位作者 YANG Jinshan ZHANG Xiangyu KAN Yanmei ZHOU Haijun XUE Yudong DONG Shaoming 《无机材料学报》 SCIE EI CAS CSCD 北大核心 2024年第8期955-964,共10页
ZrB_(2)-based ceramics typically necessitate high temperature and pressure for sintering,whereas ZrB_(2)-SiC ceramics can be fabricated at 1500℃using the process of reactive melt infiltration with Si.In comparison to... ZrB_(2)-based ceramics typically necessitate high temperature and pressure for sintering,whereas ZrB_(2)-SiC ceramics can be fabricated at 1500℃using the process of reactive melt infiltration with Si.In comparison to the conventional preparation method,reactive synthesis allows for the more facile production of ultra-high temperature ceramics with fine particle size and homogeneous composition.In this work,ZrSi_(2),B4C,and C were used as raw materials to prepare ZrB_(2)-SiC via combination of tape casting and reactive melt infiltration herein referred to as ZBC ceramics.Control sample of ZrB_(2)-SiC was also prepared using ZrB_(2) and SiC as raw materials through an identical process designated as ZS ceramics.Microscopic analysis of both ceramic groups revealed smaller and more uniformly distributed particles of the ZrB_(2) phase in ZBC ceramics compared to the larger particles in ZS ceramics.Both sets of ceramics underwent cyclic oxidation testing in the air at 1600℃for a cumulative duration of 5 cycles,each cycle lasting 2 h.Analysis of the oxidation behavior showed that both ZBC ceramics and ZS ceramics developed a glassy SiO_(2)-ZrO_(2) oxide layer on their surfaces during the oxidation.This layer severed as a barrier against oxygen.In ZBC ceramics,ZrO_(2) is finely distributed in SiO_(2),whereas in ZS ceramics,larger ZrO_(2) particles coexist with glassy SiO_(2).The surface oxide layer of ZBC ceramics maintains a dense structure because the well-dispersed ZrO_(2) increases the viscosity of glassy SiO_(2),preventing its crystallization during the cooling.Conversely,some SiO_(2) in the oxide layer of ZS ceramics may crystallize and form a eutectic with ZrO_(2),leading to the formation of ZrSiO_(4).This leads to cracking of the oxide layer due to differences in thermal expansion coefficients,weakening its barrier effect.An analysis of the oxidation resistance shows that ZBC ceramics exhibit less increase in oxide layer thickness and mass compared to ZS ceramics,suggesting superior oxidation resistance of ZBC ceramics. 展开更多
关键词 ultra-high temperature ceramic ZRB2-SIC oxidation behavior reactive melt infiltration
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Microstructure,interfacial reaction behavior,and mechanical properties of Ti_3AlC_(2)reinforced Al6061 composites
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作者 Zhi-bin LIU Jia-bao BAO +1 位作者 Wen-jie HU Hong YAN 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第9期2756-2771,共16页
The interfacial reaction behavior of Al and Ti_3AlC_(2)at different pouring temperatures and its effect on the microstructure and mechanical properties of the composites were investigated.The results show that the add... The interfacial reaction behavior of Al and Ti_3AlC_(2)at different pouring temperatures and its effect on the microstructure and mechanical properties of the composites were investigated.The results show that the addition of3.0 wt.%Ti_3AlC_(2)refines the average grain size ofα(Al)in the composite by 50.1%compared to Al6061 alloy.Morphological analyses indicate that an in-situ Al_(3Ti)transition layer of-180 nm in thickness is generated around the edge of Ti_3AlC_(2)at 720℃,forming a well-bonded Al-Al_(3Ti)interface.At this processing temperature,the ultimate tensile strength of A16061-3.0 wt.%Ti_3AlC_(2)composite is 199.2 MPa,an improvement of 41.5%over the Al6061 matrix.Mechanism analyses further elucidate that 720℃is favourable for forming the nano-sized transition layer at the Ti_3AlC_(2)edges.And,the thermal mismatch strengthening plays a dominant role in this state,with a strengthening contribution of about 74.8%. 展开更多
关键词 Al6061 composites TI3ALC2 MICROSTRUCTURE interfacial reaction tensile mechanical properties
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Ablation behaviour and mechanical performance of ZrB_(2)-ZrC-SiC modified carbon/carbon composites prepared by vacuum infiltration combined with reactive melt infiltration
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作者 ZHANG Jia-ping SU Xiao-xuan +2 位作者 LI Xin-gang WANG Run-ning FU Qian-gang 《新型炭材料(中英文)》 SCIE EI CAS CSCD 北大核心 2024年第4期633-644,共12页
The development of advanced aircraft relies on high performance thermal-structural materials,and carbon/carbon com-posites(C/C)composited with ultrahigh-temperature ceramics are ideal candidates.However,the traditiona... The development of advanced aircraft relies on high performance thermal-structural materials,and carbon/carbon com-posites(C/C)composited with ultrahigh-temperature ceramics are ideal candidates.However,the traditional routes of compositing are either inefficient and expensive or lead to a non-uniform distribution of ceramics in the matrix.Compared with the traditional C/C-ZrC-SiC composites prepared by the reactive melt infiltration of ZrSi_(2),C/C-ZrB_(2)-ZrC-SiC composites prepared by the vacuum infiltration of ZrB_(2) combined with reactive melt infiltration have the higher content and more uniform distribution of the introduced ceramic phases.The mass and linear ablation rates of the C/C-ZrB_(2)-ZrC-SiC composites were respectively 68.9%and 29.7%lower than those of C/C-ZrC-SiC composites prepared by reactive melt infiltration.The ablation performance was improved because the volatilization of B_(2)O_(3),removes some of the heat,and the more uniformly distributed ZrO_(2),that helps produce a ZrO2-SiO2 continu-ous protective layer,hinders oxygen infiltration and decreases ablation. 展开更多
关键词 C/C composites ZrB_(2)-ZrC-SiC Vacuum filtration Reactive melt infiltration Ablation.
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Syntheses,crystal structures,and catalytic properties of three zinc(Ⅱ),cobalt(Ⅱ)and nickel(Ⅱ)coordination polymers constructed from 5⁃(4⁃carboxyphenoxy)nicotinic acid
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作者 LING Weizhong CHEN Xiangyun +2 位作者 LIU Wenjing HUANG Yingkai LI Yu 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第9期1803-1810,共8页
Three zinc(Ⅱ),cobalt(Ⅱ),and nickel(Ⅱ)coordination polymers,namely[Zn(μ^(3-)cpna)(μ-dpea)_(0.5)]_(n)(1),[Co(μ^(3-)cpna)(μ-dpey)_(0.5)]_(n)(2),and[Ni(μ^(3-)cpna)(μ-dpey)_(0.5)(H_(2)O)]_(n)(3),have been construc... Three zinc(Ⅱ),cobalt(Ⅱ),and nickel(Ⅱ)coordination polymers,namely[Zn(μ^(3-)cpna)(μ-dpea)_(0.5)]_(n)(1),[Co(μ^(3-)cpna)(μ-dpey)_(0.5)]_(n)(2),and[Ni(μ^(3-)cpna)(μ-dpey)_(0.5)(H_(2)O)]_(n)(3),have been constructed hydrothermally using H_(2)cpna(5-(4-carboxyphenoxy)nicotinic acid),dpea(1,2-di(4-pyridyl)ethane),dpey(1,2-di(4-pyridyl)ethylene),and zinc,cobalt,and nickel chlorides at 160℃.The products were isolated as stable crystalline solids and were characterized by IR spectra,elemental analyses,thermogravimetric analyses,and single-crystal X-ray diffraction analyses.Single-crystal X-ray diffraction analyses revealed that three compounds crystallize in the triclinic system,space group P1.Compounds 1-3 show 2D layer structures.The catalytic activities in the Knoevenagel condensation reaction of these compounds were investigated.Compounds 1 and 2 exhibit effective catalytic activities in the Knoevenagel condensa-tion reaction at room temperature.For this reaction,various parameters were optimized,followed by the investiga-tion of the substrate scope.CCDC:2335676,1;2335677,2;2335678,3. 展开更多
关键词 coordination polymer dicarboxylic acid catalytic property Knoevenagel condensation reaction
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Microstructure and ablation behavior of Zr-based ultra-high-temperature gradient composites
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作者 Qing-hua LIU Tian TIAN +2 位作者 Wei SUN Hong-bo ZHANG Xiang XIONG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第9期2889-2899,共11页
To obtain high-performance Zr-based ultra-high-temperature composites,Zr-based ultra-high-temperature gradient composites were prepared by changing the laying method of the infiltrant via reactive melt infiltration.Th... To obtain high-performance Zr-based ultra-high-temperature composites,Zr-based ultra-high-temperature gradient composites were prepared by changing the laying method of the infiltrant via reactive melt infiltration.The effects of different infiltrant laying methods on the microstructure and ablative properties of Zr-based ultrahigh-temperature gradient composites were investigated.The results showed that the gradient structure of the Zr-based ultrahigh-temperature gradient composites differed when the composition ratio of the infiltrant was changed.When the thicknesses of the Zr/Mo/Si layers were 6/4/12 mm and 8/2/12 mm,the SiMoZrC solid solution content in the samples increased and decreased along the infiltration direction,respectively.The gradient samples were ablated in an oxyacetylene flame at 3000°C for 40 s.The ablation resistance of the sample was the highest when the infiltrant was a powder and the thickness of the Zr/Mo/Si layer was 6/4/12 mm. 展开更多
关键词 reactive melt infiltration ceramic-matrix composites gradient material MICROSTRUCTURE ablation property
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Regulating crystal phase of TiO_(2) to enhance catalytic activity of Ni/TiO_(2) for solar-driven dry reforming of methane
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作者 HE Zhanjun GONG Kun +3 位作者 DAI Yuanyuan NIU Qiang LIN Tiejun ZHONG Liangshu 《燃料化学学报(中英文)》 EI CAS CSCD 北大核心 2024年第9期1203-1213,共11页
Ni/TiO_(2) catalyst is widely employed for photo-driven DRM reaction while the influence of crystal structure of TiO_(2) remains unclear.In this work,the rutile/anatase ratio in supports was successfully controlled by... Ni/TiO_(2) catalyst is widely employed for photo-driven DRM reaction while the influence of crystal structure of TiO_(2) remains unclear.In this work,the rutile/anatase ratio in supports was successfully controlled by varying the calcination temperature of anatase-TiO_(2).Structural characterizations revealed that a distinct TiO_(x) coating on the Ni nanoparticles(NPs)was evident for Ni/TiO_(2)-700 catalyst due to strong metal-support interaction.It is observed that the TiOx overlayer gradually disappeared as the ratio of rutile/anatase increased,thereby enhancing the exposure of Ni active sites.The exposed Ni sites enhanced visible light absorption and boosted the dissociation capability of CH4,which led to the much elevated catalytic activity for Ni/TiO_(2)-950 in which rutile dominated.Therefore,the catalytic activity of solar-driven DRM reaction was significantly influenced by the rutile/anatase ratio.Ni/TiO_(2)-950,characterized by a predominant rutile phase,exhibited the highest DRM reactivity,with remarkable H_(2) and CO production rates reaching as high as 87.4 and 220.2 mmol/(g·h),respectively.These rates were approximately 257 and 130 times higher,respectively,compared to those obtained on Ni/TiO_(2)-700 with anatase.This study suggests that the optimization of crystal structure of TiO_(2) support can effectively enhance the performance of photothermal DRM reaction. 展开更多
关键词 dry reforming of methane photothermal catalysis crystal phase TiO_(2) metal-support interaction
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Hydrogen production performance of the non⁃platinum⁃based MoS_(2)/CuS cathode in microbial electrolytic cells
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作者 HAO Pingping LI Fangfang +5 位作者 WANG Yawen LI Houfen ZHANG Xiao LI Rui WANG Lei LIU Jianxin 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第9期1811-1824,共14页
MoS_(2)/CuS composite catalysts were successfully synthesized using a one-step hydrothermal method with sodium molybdate dihydrate,thiourea,oxalic acid,and copper nitrate trihydrate as raw materials.The hydrogen pro-d... MoS_(2)/CuS composite catalysts were successfully synthesized using a one-step hydrothermal method with sodium molybdate dihydrate,thiourea,oxalic acid,and copper nitrate trihydrate as raw materials.The hydrogen pro-duction performance of MoS_(2)/CuS prepared with different molar ratios of Mo to Cu precursors(n_(Mo)∶n_(Cu))as cathodic catalysts was investigated in the two-chamber microbial electrolytic cell(MEC).X-ray diffraction(XRD),X-ray pho-toelectron spectroscopy(XPS),scanning electron microscopy(SEM),transmission electron microscope(TEM),linear scanning voltammetry(LSV),electrochemical impedance analysis(EIS),and cyclic voltammetry(CV)were used to characterize the synthesized catalysts for testing and analyzing the hydrogen-producing performance.The results showed that the hydrogen evolution performance of MoS_(2)/CuS-20%(nMo∶nCu=5∶1)was better than that of platinum(Pt)mesh,and the hydrogen production rate of MoS_(2)/CuS-20%as a cathode in MEC was(0.2031±0.0237)m^(3)_(H_(2))·m^(-3)·d^(-1) for 72 h at an applied voltage of 0.8 V,which was slightly higher than that of Pt mesh of(0.1886±0.0134)m^(3)_(H_(2))·m^(-3)·d^(-1).The addition of a certain amount of CuS not only regulates the electron transfer ability of MoS_(2) but also increases the density of active sites. 展开更多
关键词 microbial electrolysis cell hydrogen evolution reaction MoS_(2)/CuS composite catalyst Pt mesh
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Effects of temperature, particle size, and air humidity on sensibility of typical high-energetic explosives
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作者 WU Sanzhen FANG Mingkun +3 位作者 WU Xingliang GUO Guangfei WANG Junhong XU Sen 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2024年第3期408-416,共9页
The production and utilization of high-energetic explosives often pose a range of safety hazards,with sensitivity being a key factor in evaluating these risks.To investigate how temperature,particle size,and air humid... The production and utilization of high-energetic explosives often pose a range of safety hazards,with sensitivity being a key factor in evaluating these risks.To investigate how temperature,particle size,and air humidity affect the responsiveness of commonly used high-energetic explosives,a series of BAM(Bundesanstalt für Materialforschung und-prüfung)impact and friction sensitivity tests were carried out to determine the critical impact energy and critical load pressure of four representative high-energetic explosives(RDX,HMX,PETN and CL-20)under different temperatures,particle sizes,and air humidity conditions.The experimental findings facilitated an examination of temperature and particle size affecting the sensitivity of high-energetic explosives,along with an assessment of the influence of air humidity on sensitivity testing.The results clearly indicate that high-energetic explosives display a substantial decline in critical reaction energy when subjected to micrometre-sized particles and an air humidity level of 45%at a temperature of 90℃.Furthermore,it was noted that the critical reaction energy of high-energetic explosives diminishes with an increase in temperature within 25℃−90℃.In the same vein,as the particle sizes of high-energetic explosives increase,so does the critical reaction energy for micrometre-sized particles.High air humidity significantly affects the sensitivity testing of high-energetic explosives,emphasizing the importance of refraining from conducting sensitivity tests in such conditions. 展开更多
关键词 high-energetic explosives TEMPERATURE particle size air humidity critical reaction energy
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Synergistic effect of heterogeneous single atoms and clusters for improved catalytic performance
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作者 Long Liu Wenting Gao +5 位作者 Yiling Ma Kainan Mei Wenlong Wu Hongliang Li Zhirong Zhang Jie Zeng 《中国科学技术大学学报》 CAS CSCD 北大核心 2024年第6期34-40,I0010,共8页
Electrocatalytic water splitting provides an efficient method for the production of hydrogen.In electrocatalytic water splitting,the oxygen evolution reaction(OER)involves a kinetically sluggish four-electron transfer... Electrocatalytic water splitting provides an efficient method for the production of hydrogen.In electrocatalytic water splitting,the oxygen evolution reaction(OER)involves a kinetically sluggish four-electron transfer process,which limits the efficiency of electrocatalytic water splitting.Therefore,it is urgent to develop highly active OER catalysts to accelerate reaction kinetics.Coupling single atoms and clusters in one system is an innovative approach for developing efficient catalysts that can synergistically optimize the adsorption and configuration of intermediates and improve catalytic activity.However,research in this area is still scarce.Herein,we constructed a heterogeneous single-atom cluster system by anchoring Ir single atoms and Co clusters on the surface of Ni(OH)_(2)nanosheets.Ir single atoms and Co clusters synergistically improved the catalytic activity toward the OER.Specifically,Co_(n)Ir_(1)/Ni(OH)_(2)required an overpotential of 255 mV at a current density of 10 mA·cm^(−2),which was 60 mV and 67 mV lower than those of Co_(n)/Ni(OH)_(2)and Ir1/Ni(OH)_(2),respectively.The turnover frequency of Co_(n)Ir_(1)/Ni(OH)_(2)was 0.49 s^(−1),which was 4.9 times greater than that of Co_(n)/Ni(OH)_(2)at an overpotential of 300 mV. 展开更多
关键词 single-atom cluster catalysts synergistic effect oxygen evolution reaction
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Recent Advances in Transition Metal-Based Catalysts for Electrocatalytic Nitrate Reduction Reaction
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作者 LUO Hongxia CHEN Jun YANG Jianping 《Journal of Donghua University(English Edition)》 CAS 2024年第4期333-348,共16页
The accumulation of excessive nitrate in the atmosphere not only jeopardizes human health but also disrupts the balance of the nitrogen cycle in the ecosystem.Among various nitrate removal technologies,electrocatalyti... The accumulation of excessive nitrate in the atmosphere not only jeopardizes human health but also disrupts the balance of the nitrogen cycle in the ecosystem.Among various nitrate removal technologies,electrocatalytic nitrate reduction reaction(eNO_(3)RR)has been widely studied for its advantages of being eco-friendly,easy to operate,and controllable under environmental conditions with renewable energy as the driving force.Transition metal-based catalysts(TMCs)have been widely used in electrocatalysis due to their abundant reserves,low costs,easy-to-regulate electronic structure and considerable electrochemical activity.In addition,TMCs have been extensively studied in terms of the kinetics of the nitrate reduction reaction,the moderate adsorption energy of nitrogen-containing species and the active hydrogen supply capacity.Based on this,this review firstly discusses the mechanism as well as analyzes the two main reduction products(N_(2)and NH_(3))of eNO_(3)RR,and reveals the basic guidelines for the design of efficient nitrate catalysts from the perspective of the reaction mechanism.Secondly,this review mainly focuses on the recent advances in the direction of eNO_(3RR)with four types of TMCs,Fe,Co,Ni and Cu,and unveils the interfacial modulation strategies of Fe,Co,Ni and Cu catalysts for the activity,reaction pathway and stability.Finally,reasonable suggestions and opportunities are proposed for the challenges and future development of eNO_(3)RR.This review provides far-reaching implications for exploring cost-effective TMCs to replace high-cost noble metal catalysts(NMCs)for eNO_(3)RR. 展开更多
关键词 electrocatalysis nitrate reduction reaction transition metal-based catalyst(TMC) reaction mechanism nitrogen cycle
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Mesoporous Carbon Nanofibers Loaded with Ordered PtFe Alloy Nanoparticles for Electrocatalytic Nitrate Reduction to Ammonia
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作者 XIE Meng LUO Wei QIU Pengpeng 《Journal of Donghua University(English Edition)》 CAS 2024年第4期365-376,共12页
Highly dispersed bimetallic alloy nanoparticle electrocatalysts have been demonstrated to exhibit exceptional performance in driving the nitrate reduction reaction(NO_(3)RR)to generate ammonia(NH_(3)).In this study,we... Highly dispersed bimetallic alloy nanoparticle electrocatalysts have been demonstrated to exhibit exceptional performance in driving the nitrate reduction reaction(NO_(3)RR)to generate ammonia(NH_(3)).In this study,we prepared mesoporous carbon nanofibers(mCNFs)functionalized with ordered PtFe alloys(O-PtFe-mCNFs)by a composite micelle interface-induced co-assembly method using poly(ethylene oxide)-block-polystyrene(PEO-b-PS)as a template.When employed as electrocatalysts,O-PtFe-mCNFs exhibited superior electrocatalytic performance for the NO_(3RR)compared to the mCNFs functionalized with disordered PtFe alloys(D-PtFe-mCNFs).Notably,the NH_(3)production performance was particularly outstanding,with a maximum NH_(3)yield of up to 959.6μmol/(h·cm~2).Furthermore,the Faraday efficiency(FE)was even 88.0%at-0.4 V vs.reversible hydrogen electrode(RHE).This finding provides compelling evidence of the potential of ordered PtFe alloy catalysts for the electrocatalytic NO_(3)RR. 展开更多
关键词 ordered PtFe alloy mesoporous carbon nanofiber(mCNF) nitrate reduction reaction(NO3RR) ammonia(NH3)production reaction
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“反应”与“反映”的用法
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作者 本刊编辑部 《中华肩肘外科电子杂志》 2018年第4期296-296,共1页
一、“反应”的常见用法:1、机体受到刺激后引发的活动。例如:(1)地震前,有的动物有异常反应。(2)有人对这种药会出现轻微的腹泻等反应。2、事情所引起的意见、态度或行动。例如:(1)他的发言在会议上引起强烈反应。(2)这个新规定群众的... 一、“反应”的常见用法:1、机体受到刺激后引发的活动。例如:(1)地震前,有的动物有异常反应。(2)有人对这种药会出现轻微的腹泻等反应。2、事情所引起的意见、态度或行动。例如:(1)他的发言在会议上引起强烈反应。(2)这个新规定群众的反应还是比较好的。 展开更多
关键词 “反应” “反映” 机体
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从ADR到药物警戒——访广东省药品不良反应监测中心邓剑雄和他的团队
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作者 于丽 《中国处方药》 2007年第10期50-52,共3页
有关"反应停"事件的报道,无论是文字还是图片每次看到都让人怵目惊心。然而当在北京街头与一位"海豹肢"患者擦肩而过,亲眼见他用未发育完全的手臂和手指"拿"着一份文件,那一刻的震惊才让我真正体会到药... 有关"反应停"事件的报道,无论是文字还是图片每次看到都让人怵目惊心。然而当在北京街头与一位"海豹肢"患者擦肩而过,亲眼见他用未发育完全的手臂和手指"拿"着一份文件,那一刻的震惊才让我真正体会到药物不良反应给现实带来的残酷。药物不良反应监测是一个年轻的学科,广东省药品不良反应监测中心更是一个年轻的机构,然而正是这个始成立于2002年的机构在去年的"齐二药"事件中经历了考验,证明了自身的价值。该中心依靠其信息管理平台的功能,已从对药品ADR的监测扩大到药物警戒的范畴。在该中心成立5周年之际,我们有幸走访了这个年轻而充满活力的队伍,并近距离地感受到中心主任邓剑雄和他的团队对于开创一片事业的无比热诚与重于泰山的责任心。 展开更多
关键词 药品不良反应监测中心 药物警戒 广东省 ADR 药物不良反应监测 “反应停” 信息管理 海豹肢
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品牌应该触发的五种消费者反应
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《广告主》 2015年第6期15-15,共1页
唯美的韩剧总是吸引无数少男少女,而一些好的品牌广告就像韩剧一样,他们做到了让目标消费者对号入座,他们把自己想像成广告片中的男女主角,去感受那一份感动、喜悦、刺激,哪怕是痛苦。品牌能够有效触发当代消费者情感认同的“反应... 唯美的韩剧总是吸引无数少男少女,而一些好的品牌广告就像韩剧一样,他们做到了让目标消费者对号入座,他们把自己想像成广告片中的男女主角,去感受那一份感动、喜悦、刺激,哪怕是痛苦。品牌能够有效触发当代消费者情感认同的“反应”概括为以下五种:一是让消费者感受到“归属感、参与感”。任何人都不愿意孤立,我们喜欢同一个球队、喜欢一个明星,因为从中能找到共同话题和情感共鸣。品牌需要提供一种情感、情节、情境,让消费者能够“进入到”我们,让消费者觉得我们是一伙人。 展开更多
关键词 消费者反应 品牌广告 触发 情感认同 目标消费者 “反应” 情感共鸣 女主角
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“反映”还是“反应”(大圣修学记系列之十四)
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作者 陈卫平 《金色少年(读写小达人)》 2014年第6期36-36,共1页
悟空在作文中这样写道:“当时,亏得俺老孙反映快,不然,师父他早被那妖怪给掳走了。”“悟空,这句话写得不错,不过,有一个词你却用错了!‘反映’应该换成‘反应’!”师父一边说一边用红笔将这个词改了。
关键词 “反应” “反映” 学记 中这 作文
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