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Single-atom catalysis:a promising avenue for precisely controlling reaction pathways

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Frontiers of Chemical Science and Engineering 2024年第7期18卷 97-120页

作者： xiaobo yang Xuning Li Yanqiang Huang State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China

Single-atom catalysts (SACs), characterized by exceptionally high atom efficiency, have garnered significant attention across various catalytic reactions. Recent studies have showcased SACs with robust capabilities for precise catalysis, specifically targeting reactions along designated pathways. This review focuses on the advances in the precise activation and reconstruction of chemical bonds on SACs, including precise activation of C–O and C–H bonds and selective couplings involving C–C and C–N bonds. Our discussion begins with a thorough exploration of the factors that render SACs skilled in precise catalytic processes, encompassing the narrow d-band electronic state of single atom site resulting in the adsorption tendency, isolate site resulting in unique adsorption structure, and synergy effect of a single atom site with its neighbors. Subsequently, we elaborate on the applications of SACs in electrocatalysis and thermocatalysis including four prominent reactions, namely, electrochemical CO_(2) reduction, urea electrochemical synthesis, CO_(2) hydrogenation, and CH4 activation. Then the concept of rational design of SACs for precisely controlling reaction pathways is discussed from the aspects of pore structure design, support-metal strong interaction, and support hydrophilic/hydrophobic. Finally, we summarize the challenges encountered by SACs in the field of precise catalytic processes and outline prospects for their further development in this domain.

关键词： single atom catalysts selective oxidation CO_(2)RR bond coupling

THE EXACT RECOVERY OF SPARSE SIGNALS VIA ORTHOGONAL MATCHING PURSUIT

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Journal of Computational Mathematics 2016年第1期34卷 70-86页

作者： Anping Liao Jiaxin Xie xiaobo yang PengWang College of Mathematics and Econometrics Hunan University Changsha 410082 China Department of Mathematics Wuyi University Jiangmen 529020 China

This paper aims to investigate sufficient conditions for the recovery of sparse signals via the orthogonal matching pursuit （OMP） algorithm. In the noiseless case, we present a novel sufficient condition for the exact recovery of all k-sparse signals by the OMP algorithm, and demonstrate that this condition is sharp. In the noisy case, a sufficient condition for recovering the support of k-sparse signal is also presented. Generally, the computation for the restricted isometry constant （RIC） in these sufficient conditions is typically difficult, therefore we provide a new condition which is not only computable but also sufficient for the exact recovery of all k-sparse signals.

关键词： Compressed sensing Sparse signal recovery Restricted orthogonality constant(ROC) Restricted isometry constant (RIC) Orthogonal matching pursuit (OMP).

Chemistry and biology of Pestalotiopsis-derived natural products

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Fungal Diversity 2014年第3期66卷 37-68页

作者： Jing Xu xiaobo yang Qiang Lin Key Laboratory of Protection and Development Utilization of Tropical Crop Germplasm Resources Ministry of EducationCollege of Material and Chemical EngineeringHainan UniversityHaikou 570228People’s Republic of China Institute of Functional Biomolecules State Key Laboratory of Pharmaceutical BiotechnologyNanjing UniversityNanjing 210093People’s Republic of China Key laboratory of water pollution treatment&resource reuse of Hainan province Hainan Normal UniversityHaikou 571158People’s Republic of China

Species within the fungal genus Pestalotiopsis have become a topic of research in many microbial-chemical and pharmacological laboratories because they contain structurally complex,biologically active *** article is a follow-up to a previous review(Xu,Ebada,and Proksch,Fungal Divers 44:15–31,2010).It focuses particularly on new findings concerning the chemistry and bioactivity of Pestalotiopsis sp.,covering a period ranging from August 2010 to August *** 160 metabolites were isolated from Pestalotiopsis species during this period and their structures are reported within a biogenetic *** showed antitumor,antifungal,and antimicrobial activities to be the most notable bioactivities of secondary metabolites isolated from this *** biogenetic pathways associated with the alkaloids,sesquiterpenes,quinines,xanthones,and lactones covered in this review are highlighted.

关键词： Secondary metabolites Bioactivity Biogenetic relationships

Novel LFM Jammer Suppression Algorithm for DSSS in FRFT Domain

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Journal of Beijing Institute of Technology 2019年第4期28卷 783-789页

作者： Jining Feng xiaobo yang Jun Wang School of Technology Hebei Normal UniversityShijiazhuang 050031China Department of Electronic Engineering Shijiazhuang Vocational and Technical CollegeShijiazhuang 050081China School of Electronics and Information Engineering Beijing Jiaotong UniversityBeijing 100044China

A novel algorithm is proposed to resolve the defects in the traditional linear frequency modulation(LFM)jamming suppression algorithm in the fractional Fourier transform(FRFT)*** traditional LFM jamming suppression algorithm in the FRFT domain has some *** example,the exact threshold is difficult to set and both the signal-to-noise ratio(SNR)loss and spectrum leakage are serious in strong jamming-to-signal ratio(JSR)***,overlapping and inverse windowing techniques are used in the FRFT domain to reduce the spectrum leakage and the SNR *** the condition that only the direct sequence spread spectrum(DSSS)signal and white Gaussian noise are present,the amplitude of the received signal after FRFT is assumed to be Rayleigh *** on the distribution characteristic,hypothesis testing is used to suppress the jamming spectrum using the *** results show that the performance of proposed algorithm is better than that of the conventional algorithms,especially in a strong jamming and multi component LFM jamming environment.

关键词： direct sequence spread spectrum(DSSS) fractional Fourier transform(FRFT) linear frequency modulation(LFM)jamming inverse windowed

Anti-Jamming Algorithm Based on Spatial Blind Search for Global Navigation Satellite System Receiver

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Journal of Beijing Institute of Technology 2020年第1期29卷 103-109页

作者： Jining Feng xiaobo yang Haibin Ma Jun Wang School of Technology Hebei Normal UniversityShijiazhuang 050031China Department of Electronic Engineering Shijiazhuang Vocational and Technical CollegeShijiazhuang 050081China School of Electronics and Information Engineering Beijing Jiaotong UniversityBeijing 100044China

A novel subspace projection anti-jamming algorithm based on spatial blind search is proposed,which uses multiple single-constrained subspace projection parallel *** the direction of arrival(DOA)of a satellite signal is unknown,the traditional subspace projection anti-jamming algorithm cannot form the correct beam *** overcome the problem of the traditional subspace projection algorithm,multiple single-constrained subspace projection parallel filters are *** single-constrained anti-jamming subspace projection algorithm obtains the optimal weight vector by searching the DOA of the satellite signal and uses the output of cross correlation as a decision *** results show that the algorithm can suppress the jamming effectively,and generate high gain toward the desired *** research provides a new idea for the engineering implementation of a multi-beam anti-jamming algorithm based on subspace projection.

关键词： global navigation satellite system(GNSS) anti-jamming spatial blind search subspace projection

Research on Fatigue Damage Behavior of Main Beam Sub-Structure of Composite Wind Turbine Blade

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Structural Durability & Health Monitoring 2024年第3期18卷 277-297页

作者： Haixia Kou Bowen yang Xuyao Zhang xiaobo yang Haibo Zhao School of Mechanical Engineering Lanzhou Jiaotong UniversityLanzhou730070China School of New Energy and Power Engineering Lanzhou Jiaotong UniversityLanzhou730070China

Given the difficulty in accurately evaluating the fatigue performance of large composite wind turbine blades(referred to as blades),this paper takes the main beam structure of the blade with a rectangular cross-sectionas the simulation object and establishes a composite laminate rectangular beam structure that simultaneouslyincludes the flange,web,and adhesive layer,referred to as the blade main beam sub-structure specimen,throughthe definition of blade *** paper examines the progressive damage evolution law of the compositelaminate rectangular beam utilizing an improved 3D Hashin failure criterion,cohesive zone model,B-K failurecriterion,and computer simulation *** static loading,the layup angle of the anti-shear web hasa close relationship with the static load-carrying capacity of the composite laminate rectangular beam;under fatigueloading,the fatigue damage will first occur in the lower flange adhesive area of the whole composite laminaterectangular beam and ultimately result in the fracture failure of the entire *** results provide a theoreticalreference and foundation for evaluating and predicting the fatigue performance of the blade main beamstructure and even the full-size blade.

关键词： Composite laminate wind turbine blade sub-structure progressive damage analysis user material subroutine cohesive zone model

Visible-light-induced regioselective cross-dehydrogenative coupling of 2-isothiocyanatonaphthalenes with amines using molecular oxygen

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Science China Chemistry 2020年第11期63卷 1652-1658页

作者： Ziyu Gan Guoqing Li xiaobo yang Qiuli Yan Guiyun Xu Gaoyang Li Yuan-Ye Jiang Daoshan yang Key Laboratory of Optic-electric Sensing and Analytical Chemistry for Life Science Ministry of EducationShandong KeyLaboratory of Biochemical AnalysisCollege of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdao 266042China School of Chemistry and Chemical Engineering Qufu Normal UniversityQufu 273165China Institute of Catalysis for Energy and Environment College of Chemistry&Chemical EngineeringShenyang Normal UniversityShenyang 110034China Qingdao West Coast New Area Poli Junior Middle School Qingdao 266409China

An efficient and eco-friendly protocol for the construction of naphtho[2,1-d]thiazol-2-amines through visible-light photoredox-catalyzed C(sp2)–H/S–H cross-dehydrogenative coupling reactions between 2-isothiocyanatonaphthalenes and amines was *** this reaction,the new C–N and C–S bonds are formed simultaneously in a single *** new method provides a straightforward approach for constructing valuable sulfur-containing compounds.

关键词： visible light cross-dehydrogenative coupling C-S bond synthetic methods metal-free

A highly active VOx-MnOx/CeO_(2) for selective catalytic reduction of NO:The balance between redox property and surface acidity

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Journal of Rare Earths 2021年第11期39卷 1370-1381,I0003页

作者： Runnong yang Zihan Gao Ming Sun Guangying Fu Gao Cheng Wuyuan Liu xiaobo yang Xiangyun Zhao Lin Yu Key Laboratory of Clean Chemistry Technology of Guangdong Regular Higher Education Institutions Guangzhou Key Laboratory of Clean Transportation Energy ChemistrySchool of Chemical Engineering and Light IndustryGuangdong University of TechnologyGuangzhou 510006China School of Chemistry Sun Yat-Sen UniversityGuangzhou 510275China Waygreen Technologies Inc.Guangzhou 511441China

Excellent catalysts with low-temperature activity and relatively wide temperature window for selective catalytic reduction of NO with ammonia(NH_(3)-SCR) are highly demanded in view of the practical treatment of ***,we have designed a highly active VOx-MnOx/CeO_(2) material based on the intrinsic requirement of SCR reaction for catalyst,namely redox sites and surface acid *** vanadium oxide and manganese oxide are highly dispersed over the ceria mesosphere via simple incipient wetness *** loading of manganese could introduce acid sites and enhance the redox property remarkably,while the loading of vanadium increases acid sites and weakens redox *** tentatively controlling the appropriate loading ratio of the two components,the optimal catalyst achieves a balance between redox property and surface *** work shed light on the development of new SCR catalyst with superior low temperature activity,wide work temperature window and good hydrothermal stability.

关键词： Redox property Surface acidity Highly active catalyst NH_(3)-SCR Rare earths

High C–C cleavage efficiencies of ethanol oxidation reaction on mesoporous RhPt electrocatalysts

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SusMat 2022年第6期2卷 689-698页

作者： Sufang yang xiaobo yang Xueqin Cui Xinhua Gao Houbing Zou Xili Tong Nianjun yang State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuanChina University of Chinese Academy of Sciences BeijingChina School of Chemistry and Chemical Engineering Shanxi UniversityTaiyuanChina NingXia University YinchuanChina Institute of Materials Engineering University of SiegenSiegenGermany

Optimizing the structure of an electrocatalyst is critical to achieve its outstand-ing performance as well as to establish relationships between its composition and its *** this work,a series of mesoporous RhPt electrocatalysts(RhPt-MPS)with different compositions are designed and synthesized toward the ethanol oxidation reaction(EOR).The mesoporous structure of RhPt-MPS exposes abundant surface sites and channels for mass transfer of ethanol,and thus boosts the catalytic EOR *** has been confirmed that Rh not only reduces the oxidation potential of EOR,but also effectively facilitates the breakage of C-C *** from structural and compositional advantages of the RhPt 0.6-MPS electrocatalyst,it exhibits the highest activity(2846.0 mA mg^(–1))for the EOR when compared with other RhPt-MPS,Rh-MPS,and Pt-MPS *** also delivers excellent stability and high selectivity than other electrocatalysts.

关键词： C-Cbondsplitting electrocatalysts ethanolelectro-oxidationreaction mesoporousmaterials RhPt