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An effective catalyst carrier SiO_(2):Enhancing catalytic and combustion properties of CuFe_(2)O_(4)on energetic components
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作者 Li Ding Chong Wan +2 位作者 Suhang Chen Zhao Qin Kangzhen Xu 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期383-392,共10页
To enhance the catalytic activity of copper ferrite(CuFe_(2)O_(4))nanoparticle and promote its application as combustion catalyst,a low-cost silicon dioxide(SiO_(2))carrier was employed to construct a novel CuFe_(2)O_... To enhance the catalytic activity of copper ferrite(CuFe_(2)O_(4))nanoparticle and promote its application as combustion catalyst,a low-cost silicon dioxide(SiO_(2))carrier was employed to construct a novel CuFe_(2)O_(4)/SiO_(2)binary composites via solvothermal method.The phase structure,morphology and catalytic activity of CuFe_(2)O_(4)/SiO_(2)composites were studied firstly,and thermal decomposition,combustion and safety performance of ammonium perchlorate(AP)and 1,3,5-trinitroperhydro-1,3,5-triazine(RDX)with it affecting were then systematically analyzed.The results show that CuFe_(2)O_(4)/SiO_(2)composite can remarkably either advance the decomposition peak temperature of AP and RDX,or reduce the apparent activation energy at their main decomposition zone.Moreover,the flame propagation rate of RDX was promoted by about 2.73 times with SiO_(2)content of 3 wt%,and safety property of energetic component was also improved greatly,in which depressing the electrostatic discharge sensitivity of pure RDX by about 1.89 times.In addition,the effective range of SiO_(2)carrier content in the binary catalyst is found to be 3 to 5 wt%.Therefore,SiO_(2)opens a new insight on the design of combustion catalyst carrier and will promote the application of CuFe_(2)O_(4)catalyst in solid propellant. 展开更多
关键词 Copper ferrite Silicon dioxide Combustion catalyst Thermal decomposition Laser ignition
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光学体表成像设备Catalyst的故障维修案例及日常保养方法
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作者 彭旭东 张俞 +1 位作者 何垠波 李光俊 《中国医疗设备》 2024年第4期169-173,180,共6页
本文介绍了光学体表成像设备Catalyst HD的工作原理,以及处理常见的硬件和软件故障的方法,并提供了日常维护保养方法。其中,对于硬件故障,利用Catalyst HD系统的MutilZsn软件来判断Catalyst投影器和摄像头故障,对于软件故障方面,探讨了C... 本文介绍了光学体表成像设备Catalyst HD的工作原理,以及处理常见的硬件和软件故障的方法,并提供了日常维护保养方法。其中,对于硬件故障,利用Catalyst HD系统的MutilZsn软件来判断Catalyst投影器和摄像头故障,对于软件故障方面,探讨了Catalyst HD系统在医用直线加速器上常见的Authorization Pending联锁问题的触发原因。本文为科室更好地开展光学体表引导放疗技术,高效地运用好设备提供参考意见。 展开更多
关键词 光学体表引导放射治疗 catalyst 故障维修 维护保养
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Catalytic effect in lithium metal batteries: From heterogeneous catalyst to homogenous catalyst
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作者 Haining Fan Xuan-Wen Gao +3 位作者 Hailong Xu Yichun Ding Shi-Xue Dou Wen-Bin Luo 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期305-326,I0008,共23页
Lithium metal batteries are regarded as prominent contenders to address the pressing needs owing to the high theoretical capacity.Toward the broader implementation,the primary obstacle lies in the intricate multi-elec... Lithium metal batteries are regarded as prominent contenders to address the pressing needs owing to the high theoretical capacity.Toward the broader implementation,the primary obstacle lies in the intricate multi-electron,multi-step redox reaction associated with sluggish conversion kinetics,subsequently giving rise to a cascade of parasitic issues.In order to smooth reaction kinetics,catalysts are widely introduced to accelerate reaction rate via modulating the energy barrier.Over past decades,a large amount of research has been devoted to the catalyst design and catalytic mechanism exploration,and thus the great progress in electrochemical performance has been realized.Therefore,it is necessary to make a comprehensive review toward key progress in catalyst design and future development pathway.In this review,the basic mechanism of lithium metal batteries is provided along with corresponding advantages and existing challenges detailly described.The main catalysts employed to accelerate cathode reaction with emphasis on their catalytic mechanism are summarized as well.Finally,the rational design and innovative direction toward efficient catalysts are suggested for future application in metal-sulfur/gas battery and beyond.This review is expected to drive and benefit future research on rational catalyst design with multi-parameter synergistic impacts on the activity and stability of next-generation metal battery,thus opening new avenue for sustainable solution to climate change,energy and environmental issues,and the potential industrial economy. 展开更多
关键词 Energy storage and conversion Metal battery Sulfur battery Air battery Catalytic effect Heterogeneous catalyst Homogeneous catalyst
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Clinical Analysis and Mental Health Survey of Hemophilia Carriers:a Cross-sectional Study
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作者 Wen WANG Li-juan JIANG +4 位作者 Dong-yan CUI Ai ZHANG Xiong WANG Ai-guo LIU Qun HU 《Current Medical Science》 SCIE CAS 2024年第2期435-440,共6页
Objective:Hemophilia carriers(HCs),who are heterozygous for mutations in the clotting factor VIII/clotting factor IX gene(F8 or F9),may have a wide range of clotting factor levels,from very low,similar to afflicted ma... Objective:Hemophilia carriers(HCs),who are heterozygous for mutations in the clotting factor VIII/clotting factor IX gene(F8 or F9),may have a wide range of clotting factor levels,from very low,similar to afflicted males,to the upper limit of normal,and may experience mental health issues.The purpose of this study was to provide genetic information on mothers of hemophilia patients and to understand the clotting factor activity and phenotype of HCs.Additionally,we aimed to investigate the mental health status of HCs in China.Methods:A total of 127 hemophilia mothers,including 93 hemophilia A(HA)mothers and 34 hemophilia B(HB)mothers,were enrolled in this study.Long distance PCR,multiplex PCR,and Sanger sequencing were used to analyze mutations in F8 or F9.Coagulation factor activity was detected by a one-stage clotting assay.The Symptom Checklist 90(SCL-90,China/Mandarin version)was given to HCs at the same time to assess their mental health.Results:A total of 90.6%of hemophilia mothers were diagnosed genetically as carriers,with inversion in intron 22 and missense mutations being the most common mutation types in HA and HB carriers,respectively.The median clotting factor level in carriers was 0.74 IU/mL(ranging from 0.09 to 1.74 IU/mL)compared with 1.49 IU/mL(ranging from 0.93 to 1.89 IU/mL)in noncarriers,of which 14.3%of HCs had clotting factor levels of 0.40 IU/mL or below.A total of 53.8%(7/13)of HA carriers with low clotting factor levels(less than 0.50 IU/mL)had a history of bleeding,while none of the HB carriers displayed a bleeding phenotype.The total mean score and the global severity index of the SCL-90 for surveyed HCs were 171.00(±60.37)and 1.78(±0.59),respectively.A total of 67.7%of the respondents had psychological symptoms,with obsessive-compulsive disorder being the most prevalent and severe.The pooled estimates of all nine factors were significantly higher than those in the general population(P<0.05).Conclusions:The detection rate of gene mutations in hemophilia mothers was 90.6%,with a median clotting factor level of 0.74 IU/mL,and 14.3%of HCs had a clotting factor level of 0.40 IU/mL or below.A history of bleeding was present in 41.2%of HCs with low clotting factor levels(less than 0.50 IU/mL).Additionally,given the fragile mental health status of HCs in China,it is critical to develop efficient strategies to improve psychological well-being. 展开更多
关键词 hemophilia A hemophilia B MUTATION carrier mental health
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Vertical plane depth-resolved surface potential and carrier separation characteristics in flexible CZTSSe solar cells with over 12% efficiency
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作者 Dae-Ho Son Ha Kyung Park +11 位作者 Dae-Hwan Kim Jin-Kyu Kang Shi-Joon Sung Dae-Kue Hwang Jaebaek Lee Dong-Hwan Jeon Yunae Cho William Jo Taeseon Lee JunHo Kim Sang-Hoon Nam Kee-Jeong Yang 《Carbon Energy》 SCIE EI CAS CSCD 2024年第3期36-52,共17页
Cu2ZnSn(S,Se)4(CZTSSe)solar cells have resource distribution and economic advantages.The main cause of their low efficiency is carrier loss resulting from recombination of photo-generated electron and hole.To overcome... Cu2ZnSn(S,Se)4(CZTSSe)solar cells have resource distribution and economic advantages.The main cause of their low efficiency is carrier loss resulting from recombination of photo-generated electron and hole.To overcome this,it is important to understand their electron-hole behavior characteristics.To determine the carrier separation characteristics,we measured the surface potential and the local current in terms of the absorber depth.The elemental variation in the intragrains(IGs)and at the grain boundaries(GBs)caused a band edge shift and bandgap(Eg)change.At the absorber surface and subsurface,an upward Ec and Ev band bending structure was observed at the GBs,and the carrier separation was improved.At the absorber center,both upward Ec and Ev and downward Ec-upward Ev band bending structures were observed at the GBs,and the carrier separation was degraded.To improve the carrier separation and suppress carrier recombination,an upward Ec and Ev band bending structure at the GBs is desirable. 展开更多
关键词 carrier separation CZTSSe flexible solar cell local current surface potential
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Ultrafast carrier dynamics in GeSn thin film based on time-resolved terahertz spectroscopy
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作者 黄盼盼 张有禄 +3 位作者 胡凯 齐静波 张岱南 程亮 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期164-169,共6页
We measure the time-resolved terahertz spectroscopy of GeSn thin film and studied the ultrafast dynamics of its photo-generated carriers.The experimental results show that there are photo-generated carriers in GeSn un... We measure the time-resolved terahertz spectroscopy of GeSn thin film and studied the ultrafast dynamics of its photo-generated carriers.The experimental results show that there are photo-generated carriers in GeSn under femtosecond laser excitation at 2500 nm,and its pump-induced photoconductivity can be explained by the Drude–Smith model.The carrier recombination process is mainly dominated by defect-assisted Auger processes and defect capture.The firstand second-order recombination rates are obtained by the rate equation fitting,which are(2.6±1.1)×10^(-2)ps^(-1)and(6.6±1.8)×10^(-19)cm^(3)·ps^(-1),respectively.Meanwhile,we also obtain the diffusion length of photo-generated carriers in GeSn,which is about 0.4μm,and it changes with the pump delay time.These results are important for the GeSn-based infrared optoelectronic devices,and demonstrate that Ge Sn materials can be applied to high-speed optoelectronic detectors and other applications. 展开更多
关键词 GeSn thin film time-resolved THz spectroscopy ultrafast dynamics carrier recombination
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Experimental Study on Gas Flow Uniformity in a Diesel Particulate Filter Carrier
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作者 Zhengyong Wang Jianhua Zhang +5 位作者 Guoliang Su Peixing Yang Xiantao Fan Shuzhan Bai Ke Sun Guihua Wang 《Fluid Dynamics & Materials Processing》 EI 2024年第1期193-204,共12页
A Diesel Particulate Filter(DPF)is a critical device for diesel engine exhaust products treatment.When using active-regeneration purification methods,on the one hand,a spatially irregular gas flow can produce relative... A Diesel Particulate Filter(DPF)is a critical device for diesel engine exhaust products treatment.When using active-regeneration purification methods,on the one hand,a spatially irregular gas flow can produce relatively high local temperatures,potentially resulting in damage to the carrier;On the other hand,the internal temperature field can also undergo significant changes contributing to increase this risk.This study explores the gas flow uniformity in a DPF carrier and the related temperature behavior under drop-to-idle(DTI)condition by means of bench tests.It is shown that the considered silicon carbide carrier exhibits good flow uniformity,with a temperature deviation of no more than 2%with respect to the same radius measurement point at the outlet during the regeneration stage.In the DTI test,the temperature is relatively high within r/2 near the outlet end,where the maximum temperature peak occurs,and the maximum radial temperature gradient is located between r/2 and the edge.Both these quantities grow as the soot load increases,thereby making the risk of carrier burnout greater.Finally,it is shown that the soot load limit of the silicon carbide DPF can be extended to 11 g/L,which reduces the frequency of active regeneration by approximately 40%compared to a cordierite DPF. 展开更多
关键词 DPF flow uniformity DTI silicon carbide carrier soot load
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Fullerenes and derivatives as electrocatalysts: Promises and challenges
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作者 Kun Guo Ning Li +1 位作者 Lipiao Bao Xing Lu 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第1期7-27,共21页
Carbon-based metal-free nanomaterials are promising alternatives to precious metals as electrocatalysts of key energy storage and conversion technologies.Of paramount significance are the establishment of design princi... Carbon-based metal-free nanomaterials are promising alternatives to precious metals as electrocatalysts of key energy storage and conversion technologies.Of paramount significance are the establishment of design principles by understanding the catalytic mechanisms and identifying the active sites.Distinct from sp2-conjugated graphene and carbon nanotube,fullerene possesses unique characteristics that are growingly being discovered and exploited by the electrocatalysis community.For instance,the well-defined atomic and molecular structures,the good electron affinity to tune the electronic structures of other substances,the intermolecular self-assembly into superlattices,and the on-demand chemical modification have endowed fullerene with incomparable advantages as electrocatalysts that are otherwise not applicable to other carbon ma-terials.As increasing studies are being reported on this intriguing topic,it is necessary to provide a state-of-the-art overview of the recent progress.This review takes such an initiative by summarizing the promises and challenges in the electrocatalytic applications of fullerene and its derivatives.The content is structured according to the composition and structure of fullerene,including intact fullerene(e.g.,fullerene composite and superlattices)and fullerene derivatives(e.g.,doped,endohedral,and disintegrated fullerene).The synthesis,characterization,catalytic mechanisms,and deficiencies of these fullerene-based materials are explicitly elaborated.We conclude it by sharing our perspectives on the key aspects that future efforts shall consider. 展开更多
关键词 FULLERENE Fullerene derivative Metal-free catalyst Structural defect ELECTROcatalyst
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Efficient and stable PtFe alloy catalyst for electrocatalytic methanol oxidation with high resistance to CO
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作者 Qian Yang Sifan Zhang +5 位作者 Fengshun Wu Lihua Zhu Guang Li Mingzhi Chen An Pei Yingliang Feng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期327-336,I0008,共11页
Direct methanol fuel cells(DMFC) are widely considered to be an ideal green energy conversion device but their widespread applications are limited by the high price of the Pt-based catalysts and the instability in ter... Direct methanol fuel cells(DMFC) are widely considered to be an ideal green energy conversion device but their widespread applications are limited by the high price of the Pt-based catalysts and the instability in terms of surface CO toxicity in long-term operation.Herein,the PtFe alloy nanoparticles(NPs) with small particle size(~4.12 nm) supported on carbon black catalysts with different Pt/Fe atomic ratios(Pt_(1)Fe_(2)/C,Pt_(3)Fe_(4)/C,Pt_(1)Fe_(1)/C,and Pt_(2)Fe_(1)/C) are successfully prepared for enhanced anti-CO poisoning during methanol oxidation reaction(MOR).The optimal atomic ratio of Pt/Fe for the MOR is 1:2,and the mass activity of Pt_(1)Fe_(2)/C(5.40 A mg_(Pt)^(-1)) is 13.5 times higher than that of conventional commercial Pt/C(Pt/C-JM)(0.40 A mg_(Pt)^(-1)).The introduction of Fe into the Pt lattice forms the PtFe alloy phase,and the electron density of Pt is reduced after forming the PtFe alloy.In-situ Fourier transform infrared results indicate that the addition of oxyphilic metal Fe has reduced the adsorption of reactant molecules on Pt during the MOR.The doping of Fe atoms helps to desorb toxic intermediates and regenerate Pt active sites,promoting the cleavage of C-O bonds with good selectivity of CO_(2)(58.1%).Moreover,the Pt_(1)Fe_(2)/C catalyst exhibits higher CO tolerance,methanol electrooxidation activity,and long-term stability than other Pt_(x)Fe_(y)/C catalysts. 展开更多
关键词 Alloy catalyst PTFE Methanol oxidation In-situ FTIR CO resistance
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Catalyst光学体表监测在左侧乳腺癌ABC-DIBH放射治疗中的应用
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作者 刘剑锋 钟鹤立 +4 位作者 张光伟 吴何苟 刘婷婷 高勇 李彬 《中国医疗设备》 2024年第1期61-66,共6页
目的 探讨在应用主动呼吸控制(Active Breathing Control,ABC)技术的左侧乳腺癌深吸气屏气(Deep Inspiration Breath Hold,DIBH)放疗中,使用光学体表追踪技术监测屏气的有效性和体位的重复性效果,以保证患者在放疗中吸气方式一致和体位... 目的 探讨在应用主动呼吸控制(Active Breathing Control,ABC)技术的左侧乳腺癌深吸气屏气(Deep Inspiration Breath Hold,DIBH)放疗中,使用光学体表追踪技术监测屏气的有效性和体位的重复性效果,以保证患者在放疗中吸气方式一致和体位不变,提高放射治疗的精确性。方法 选取应用ABC技术放疗的23例左侧乳腺癌患者为研究对象,以Catalyst进行治疗中DIBH体位监测,以分次内锥形束计算机断层扫描(Cone Beam Computed Tomography,CBCT)为参考标准,分别记录二者误差数据,应用Pearson法和Bland-Altman法分别评估两组误差的相关性和两种系统的一致性。将光学体表监测值与CBCT配准误差值之间的差值定义为Catalyst体表监测精度。结果 Catalyst监测在左右(x轴)方向、头脚(y轴)方向和前后(z轴)方向误差分别为(0.08±1.04)、(1.44±2.15)、(0.45±1.69)mm,CBCT配准误差分别为(0.15±1.15)、(1.51±2.28)、(0.44±1.81)mm。x轴方向和z轴方向相关系数r值分别为0.60、0.77,呈强相关;y轴方向r值为0.82,呈极强相关。二者95%CI值在x、y与z轴方向分别为[-2.01,1.86]、[-2.69,2.57]、[-2.32,2.34] mm,Catalyst监测精度在x、y、z轴方向分别为(-0.08±0.99)、(-0.06±1.34)、(0.01±1.19)mm。结论 Catalyst可有效监测使用ABC进行治疗左侧乳腺癌患者的屏气状态,能准确且实时监测患者位置,提高治疗精确度,具有临床应用价值。 展开更多
关键词 catalyst 光学体表追踪 主动呼吸控制 左侧乳腺癌 放射治疗
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Atomic Ni directional-substitution on ZnIn_(2)S_(4) nanosheet to achieve the equilibrium of elevated redox capacity and efficient carrier-kinetics performance in photocatalysis
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作者 Haibin Huang Guiyang Yu +5 位作者 Xingze Zhao Boce Cui Jinshi Yu Chenyang Zhao Heyuan Liu Xiyou Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期272-281,I0007,共11页
It is a challenge to coordinate carrier-kinetics performance and the redox capacity of photogenerated charges synchronously at the atomic level for boosting photocatalytic activity.Herein,the atomic Ni was introduced ... It is a challenge to coordinate carrier-kinetics performance and the redox capacity of photogenerated charges synchronously at the atomic level for boosting photocatalytic activity.Herein,the atomic Ni was introduced into the lattice of hexagonal ZnIn_(2)S_(4) nanosheets(Ni/ZnIn_(2)S_(4))via directionalsubstituting Zn atom with the facile hydrothermal method.The electronic structure calculations indicate that the introduction of Ni atom effectively extracts more electrons and acts as active site for subsequent reduction reaction.Besides the optimized light absorption range,the elevation of Efand ECBendows Ni/ZnIn_(2)S_(4) photocatalyst with the increased electron concentration and the enhanced reduction ability for surface reaction.Moreover,ultrafast transient absorption spectroscopy,as well as a series of electrochemical tests,demonstrates that Ni/ZnIn_(2)S_(4) possesses 2.15 times longer lifetime of the excited charge carriers and an order of magnitude increase for carrier mobility and separation efficiency compared with pristine ZnIn_(2)S_(4).These efficient kinetics performances of charge carriers and enhanced redox capacity synergistically boost photocatalytic activity,in which a 3-times higher conversion efficiency of nitrobenzene reduction was achieved upon Ni/ZnIn_(2)S_(4).Our study not only provides in-depth insights into the effect of atomic directional-substitution on the kinetic behavior of photogenerated charges,but also opens an avenue to the synchronous optimization of redox capacity and carrier-kinetics performance for efficient solar energy conversion. 展开更多
关键词 ZnIn_(2)S_(4) SUBSTITUTION carrier kinetics Redox capacity PHOTOCATALYSIS
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Efficient Direct Decomposition of NO over La_(0.8)A_(0.2)NiO_(3)(A=K, Ba, Y) Catalysts under Microwave Irradiation
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作者 王浩 ZHAO Zijian +1 位作者 DUAN Xinghui ZHOU Shijia 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第1期17-23,共7页
La_(0.8)A_(0.2)NiO_(3) (A=K,Ba,Y) catalysts supported on the microwave-absorbing ceramic heating carrier were prepared by the sol-gel method.The crystalline phase and the catalytic activity of the La_(0.8)A_(0.2)NiO_(... La_(0.8)A_(0.2)NiO_(3) (A=K,Ba,Y) catalysts supported on the microwave-absorbing ceramic heating carrier were prepared by the sol-gel method.The crystalline phase and the catalytic activity of the La_(0.8)A_(0.2)NiO_(3)catalysts were characterized by XRD and H_(2) temperature-programmed reduction (TPR).The effects of reaction temperature,oxygen concentration,and gas flow rate on the direct decomposition of nitric oxide over the synthesized catalysts were studied under microwave irradiation (2.45 GHz).The XRD results indicated that the La_(0.8)A_(0.2)NiO_(3) catalysts formed an ABO_(3) perovskite structure,and the H_(2)-TPR results revealed that the relative reducibility of the catalysts increased in the order of La_(0.8)K_(0.2)NiO_(3)>La_(0.8)Ba_(0.2)NiO_(3)>La_(0.8)Y_(0.2)Ni O_(3).Under microwave irradiation,the highest NO conversion amounted to 98.9%,which was obtained with the La_(0.8)K_(0.2)NiO_(3) catalyst at 400℃.The oxygen concentration did not inhibit the NO decomposition on the La_(0.8)A_(0.2)NiO_(3) catalysts,thus the N_(2) selectivity exceeded 99.8%under excess oxygen at 550℃.The NOconversion of the La_(0.8)A_(0.2)NiO_(3) catalysts decreased linearly with the increase in the gas flow rate. 展开更多
关键词 microwave catalysis direct decomposition of NO microwave-absorbing heating ceramics perovskite catalyst
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100 W-class green hydrogen production from ammonia at a dual-layer electrode containing a Pt-Ir catalyst for an alkaline electrolytic process
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作者 Donghyun Yoon Sunki Chung +2 位作者 Minjun Choi Eunhyeok Yang Jaeyoung Lee 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期352-360,I0009,共10页
Ammonia allows storage and transport of hydrogen over long distances and is an attractive potential hydrogen carrier.Electrochemical decomposition has recently been used for the conversion of ammonia to hydrogen and i... Ammonia allows storage and transport of hydrogen over long distances and is an attractive potential hydrogen carrier.Electrochemical decomposition has recently been used for the conversion of ammonia to hydrogen and is regarded as a future technology for production of CO_(2)-free pure hydrogen.Herein,a heterostructural Pt-Ir dual-layer electrode is developed and shown to achieve successful long-term operation in an ammonia electrolyzer with an anion exchange membrane(AEM).This electrolyzer consisted of eight membra ne electrode assemblies(MEAs)with a total geometric area of 200 cm~2 on the anode side,which resulted in a hydrogen production rate of 25 L h~(-1).We observed the degradation in MEA performance attributed to changes in the anode catalyst layer during hydrogen production via ammonia electrolysis.Furthermore,we demonstrated the relationship between the ammonia oxidation reaction(AOR)and the oxygen evolution reaction(OER). 展开更多
关键词 Ammonia oxidation Dual-layer catalyst Green hydrogen Electrolytic process Oxygen evolution reaction
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Enhanced stability of nitrogen-doped carbon-supported palladium catalyst for oxidative carbonylation of phenol
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作者 Xiaojing Liu Ruohan Zhao +4 位作者 Hao Zhao Zhimiao Wang Fang Li Wei Xue Yanji Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期19-28,共10页
Enhancing the stability of supported noble metal catalysts emerges is a major challenge in both science and industry.Herein,a heterogeneous Pd catalyst(Pd/NCF)was prepared by supporting Pd ultrafine metal nanoparticle... Enhancing the stability of supported noble metal catalysts emerges is a major challenge in both science and industry.Herein,a heterogeneous Pd catalyst(Pd/NCF)was prepared by supporting Pd ultrafine metal nanoparticles(NPs)on nitrogen-doped carbon;synthesized by using F127 as a stabilizer,as well as chitosan as a carbon and nitrogen source.The Pd/NCF catalyst was efficient and recyclable for oxidative carbonylation of phenol to diphenyl carbonate,exhibiting higher stability than Pd/NC prepared without F127 addition.The hydrogen bond between chitosan(CTS)and F127 was enhanced by F127,which anchored the N in the free amino group,increasing the N content of the carbon material and ensuring that the support could provide sufficient N sites for the deposition of Pd NPs.This process helped to improve metal dispersion.The increased metal-support interaction,which limits the leaching and coarsening of Pd NPs,improves the stability of the Pd/NCF catalyst.Furthermore,density functional theory calculations indicated that pyridine N stabilized the Pd^(2+)species,significantly inhibiting the loss of Pd^(2+)in Pd/NCF during the reaction process.This work provides a promising avenue towards enhancing the stability of nitrogen-doped carbon-supported metal catalysts. 展开更多
关键词 Supported Pd catalyst N-doped carbon Amphiphilic triblock copolymer Pyridinic nitrogen STABILITY
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Realizing methanol synthesis from CO and water via the synergistic effect of Cu^(0)/Cu^(+)over Cu/ZrO_(2) catalyst
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作者 Yuan Fang Fan Wang +10 位作者 Yang Chen Qian Lv Kun Jiang Hua Yang Huibo Zhao Peng Wang Yuyan Gan Lizhi Wu Yu Tang Xinhua Gao Li Tan 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期126-134,I0004,共10页
The optimizing utilization of ca rbon resources has drawn wide attention all over the world,while exploiting the high-efficiency catalytic routes remains a challenge.Here,a direct methanol synthesis route is realized ... The optimizing utilization of ca rbon resources has drawn wide attention all over the world,while exploiting the high-efficiency catalytic routes remains a challenge.Here,a direct methanol synthesis route is realized from pure CO and H_(2)O over 10%Cu/t-ZrO_(2) catalyst,where the time yield of methanol is144.43 mmol mol_(Cu)^(-1)h^(-1)and the methanol selectivity in hydrocarbons is 100%,The Cu species highly dispersed in the t-ZrO_(2) support lead parts of them in the cationic state.The Cu^(+)sites contribute to the dissociation of H_(2)O,providing the H*source for methanol synthesis,while the formed Cu^(0) sites promote the absorption and transfer of H*during the reaction.Moreover,the H_(2)O is even a better H resource than H_(2) due to its better dissociation effectivity in this catalytic system.The present work offers a new approach for methanol synthesis from CO and new insight into the process of supplying H donor. 展开更多
关键词 H_(2)O CO METHANOL Cu-based catalysts t-ZrO_(2)
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Preparation of Modified UiO-66 Catalyst and Its Catalytic Performance for NH_(3)-SCR Denitration
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作者 吴彦霞 梁海龙 +2 位作者 CHEN Yufeng HU Liming WANG Chunpeng 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第2期261-267,共7页
Zirconium-based metal-organic framework UiO-66 was successfully prepared by solvothermal method,and UiO-66 was modified by adding regulators such as formic acid,acetic acid,and hydrochloric acid.The NH_(3)-SCR reactiv... Zirconium-based metal-organic framework UiO-66 was successfully prepared by solvothermal method,and UiO-66 was modified by adding regulators such as formic acid,acetic acid,and hydrochloric acid.The NH_(3)-SCR reactivity of the samples was evaluated by the denitration activity evaluation system,and the UiO-66 and the regulator-modified UiO-66 were characterized by XRD,SEM,BET,FTIR,TG,NH_(3)-TPD,etc.,the effects of regulator types on the structure and properties of UiO-66 were investigated.The experimental results show that,after adding the modifier,the morphology of UiO-66 changes from irregular quadrilateral with serious agglomeration to particles with regular crystal shape and good dispersibility,and the crystal morphology of the catalyst is improved.In addition,after adding the modifier,UiO-66 has a larger specific surface area and stronger surface acidity,which optimizes the catalytic performance of UiO-66.The catalytic performance test results of NH_(3)-SCR show that the low-temperature activity of UiO-66 is poor,and it only shows a certain catalytic activity at higher temperatures.The catalytic activity of UiO-66 was significantly improved after adding the regulator.Among them,the UiO-66-HCl modified with hydrochloric acid had the best catalytic activity,and the denitration rate reached 70%when the denitration temperature was 380℃. 展开更多
关键词 UiO-66 catalyst catalytic denitration NH_(3)-SCR MODIFIED
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Single-atom catalysts for the electrochemical reduction of carbon dioxide into hydrocarbons and oxygenates
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作者 Karl Adrian Gandionco Juwon Kim +2 位作者 Lieven Bekaert Annick Hubin Jongwoo Lim 《Carbon Energy》 SCIE EI CAS CSCD 2024年第3期64-117,共54页
The electrochemical reduction of carbon dioxide offers a sound and economically viable technology for the electrification and decarbonization of the chemical and fuel industries.In this technology,an electrocatalytic ... The electrochemical reduction of carbon dioxide offers a sound and economically viable technology for the electrification and decarbonization of the chemical and fuel industries.In this technology,an electrocatalytic material and renewable energy-generated electricity drive the conversion of carbon dioxide into high-value chemicals and carbon-neutral fuels.Over the past few years,single-atom catalysts have been intensively studied as they could provide near-unity atom utilization and unique catalytic performance.Single-atom catalysts have become one of the state-of-the-art catalyst materials for the electrochemical reduction of carbon dioxide into carbon monoxide.However,it remains a challenge for single-atom catalysts to facilitate the efficient conversion of carbon dioxide into products beyond carbon monoxide.In this review,we summarize and present important findings and critical insights from studies on the electrochemical carbon dioxide reduction reaction into hydrocarbons and oxygenates using single-atom catalysts.It is hoped that this review gives a thorough recapitulation and analysis of the science behind the catalysis of carbon dioxide into more reduced products through singleatom catalysts so that it can be a guide for future research and development on catalysts with industry-ready performance for the electrochemical reduction of carbon dioxide into high-value chemicals and carbon-neutral fuels. 展开更多
关键词 ELECTROCATALYSIS electrochemical CO_(2)reduction hydrocarbons OXYGENATES single-atom catalysts
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Boosting Fischer-Tropsch Synthesis via Tuning of N Dopants in TiO_(2)@CN-Supported Ru Catalysts
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作者 Xincheng Li Yunhao Liu +10 位作者 Dejian Zhao Shuaishuai Lyu Jingwei Ye Xiaoshen Li Peipei Wu Ye Tian Yingtian Zhang Tong Ding Song Song Qingpeng Cheng Xingang Li 《Transactions of Tianjin University》 EI CAS 2024年第1期90-102,共13页
Nitrogen(N)-doped carbon materials as metal catalyst supports have attracted signifi cant attention,but the eff ect of N dopants on catalytic performance remains unclear,especially for complex reaction processes such ... Nitrogen(N)-doped carbon materials as metal catalyst supports have attracted signifi cant attention,but the eff ect of N dopants on catalytic performance remains unclear,especially for complex reaction processes such as Fischer-Tropsch synthesis(FTS).Herein,we engineered ruthenium(Ru)FTS catalysts supported on N-doped carbon overlayers on TiO_(2)nanoparticles.By regulating the carbonization temperatures,we successfully controlled the types and contents of N dopants to identify their impacts on metal-support interactions(MSI).Our fi ndings revealed that N dopants establish a favorable surface environment for electron transfer from the support to the Ru species.Moreover,pyridinic N demonstrates the highest electron-donating ability,followed by pyrrolic N and graphitic N.In addition to realizing excellent catalytic stability,strengthening the interaction between Ru sites and N dopants increases the Ru^(0)/Ru^(δ+)ratios to enlarge the active site numbers and surface electron density of Ru species to enhance the strength of adsorbed CO.Consequently,it improves the catalyst’s overall performance,encompassing intrinsic and apparent activities,as well as its ability for carbon chain growth.Accordingly,the as-synthesized Ru/TiO_(2)@CN-700 catalyst with abundant pyridine N dopants exhibits a superhigh C_(5+)time yield of 219.4 mol CO/(mol Ru·h)and C_(5+)selectivity of 85.5%. 展开更多
关键词 Fischer-Tropsch synthesis N-doped carbon materials Ruthenium catalyst Pyridinic N Metal-N interaction
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Elucidating the structure-activity relationship of Cu-Ag bimetallic catalysts for electrochemical CO_(2) reduction
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作者 Qining Huang Lili Wan +1 位作者 Qingxuan Ren Jingshan Luo 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期345-351,I0009,共8页
Developing bimetallic catalysts is an effective strategy for enhancing the activity and selectivity of electrochemical CO_(2) reduction reactions,where understanding the structure-activity relationship is essential fo... Developing bimetallic catalysts is an effective strategy for enhancing the activity and selectivity of electrochemical CO_(2) reduction reactions,where understanding the structure-activity relationship is essential for catalyst design.Herein,we prepared two Cu-Ag bimetallic catalysts with Ag nanoparticles attached to the top or the bottom of Cu nanowires.When tested in a flow cell,the Cu-Ag catalyst with Ag nanoparticles on the bottom achieved a faradaic efficiency of 54%for ethylene production,much higher than the catalyst with Ag nanoparticles on the top.The catalysts were further studied in the H-cell and zero-gap MEA cell.It was found that placing the two metals in the intensified reaction zone is crucial to triggering the tandem reaction of bimetallic catalysts.Our work elucidates the structure-activity relationship of bimetallic catalysts for CO_(2) reduction and demonstrates the importance of considering both catalyst structures and cell characteristics to achieve high activity and selectivity. 展开更多
关键词 Electrochemical CO_(2)reduction Bimetallic catalyst CU-AG Structure-activity relationship
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Non-thermal atmospheric-pressure positive pulsating corona discharge in degradation of textile dye Reactive Blue 19 enhanced by Bi_(2)O_(3) catalyst
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作者 Milica PETROVIC Dragan RADIVOJEVIC +4 位作者 Sasa RANCEV Nena VELINOV Milos KOSTIC Danijela BOJIC Aleksandar BOJIC 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第2期104-113,共10页
In this work,monoclinic Bi_(2)O_(3) was applied for the first time,to the best of our knowledge,as a catalyst in the process of dye degradation by a non-thermal atmospheric-pressure positive pulsating corona discharge... In this work,monoclinic Bi_(2)O_(3) was applied for the first time,to the best of our knowledge,as a catalyst in the process of dye degradation by a non-thermal atmospheric-pressure positive pulsating corona discharge.The research focused on the interaction of the plasma-generated species and the catalyst,as well as the role of the catalyst in the degradation process.Plasma decomposition of the anthraquinone reactive dye Reactive Blue 19(RB 19) was performed in a selfmade reactor system.Bi_(2)O_(3) was prepared by electrodeposition followed by thermal treatment,and characterized by x-ray diffraction,scanning electron microscopy and energy-dispersive xray techniques.It was observed that the catalyst promoted decomposition of plasma-generated H_(2)O_(2) into ·OH radicals,the principal dye-degrading reagent,which further attacked the dye molecules.The catalyst improved the decolorization rate by 2.5 times,the energy yield by 93.4%and total organic carbon removal by 7.1%.Excitation of the catalyst mostly occurred through strikes by plasma-generated reactive ions and radical species from the air,accelerated by the electric field,as well as by fast electrons with an energy of up to 15 eV generated by the streamers reaching the liquid surface.These strikes transferred the energy to the catalyst and created the electrons and holes,which further reacted with H_(2)O_(2) and water,producing ·OH radicals.This was indentified as the primary role of the catalyst in this process.Decolorization reactions followed pseudo first-order kinetics.Production of H_(2)O_(2) and the dye degradation rate increased with increase in the input voltage.The optimal catalyst dose was 500 mg·dm^(-3).The decolorization rate was a little lower in river water compared with that in deionized water due to the side reactions of ·OH radicals with organic matter and inorganic ions dissolved in the river water. 展开更多
关键词 corona RB 19 Bi_(2)O_(3) catalyst DEGRADATION
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