检索结果-南通市图书馆

Single-Ni-atoms on nitrogenated humic acid based porous carbon for CO_(2) electroreduction

在线全文

学校读者我要写书评

暂无评论

Frontiers of Chemical Science and Engineering 2024年第5期18卷 37-47页

作者： Delei Yu Ying chen yao chen Xiangchun Liu Xianwen Wei Ping Cui Anhui Key Laboratory of Coal Clean Conversion&Utilization School of Chemistry and Chemical EngineeringAnhui University of TechnologyMa’anshan 243002Chin

tWe proposed a facile synthesis of single-Ni-atom catalysts on low-cost porous carbon using a calcina-tion method at the temperatures of 850-1000°C,which were used for CO_(2) electrochemical reduction to *** porous carbon was prepared by carbonizing cheap and abundant humic *** structural characterizations of the as-synthesized catalysts and their electrocatalytic performances were *** results showed that the single-Ni-atom catalyst activated at 950°C showed an optimum catalytic performance,and it reached a CO Faradaic efficiency of 91.9% with a CO partial current density of 6.9 mAcm^(-2)at-0.9 V *** hydrogen electrode(RHE).Additionally,the CO Faradaic efficiency and current density of the optimum catalyst changed slightly after 8 h of continuous operation,suggesting that it possessed an excellent *** structure-activity relations indicate that the variation in the CO_(2) electroche-mical reduction performance for the as-synthesized catalysts is ascribed to the combined effects of the increase in the content of pyrrolic N,the evaporation of Ni and N,the decrease in pore volume,and the change in graphitization degree.

关键词： CO_(2) electroreduction single-Ni-atom cataly-sts humic acid based porous carbon

Design of novel RGO/2D strip-like ZIF-8/DMAOP ternary hybrid structure towards high-efficiency microwave absorption, active and passive anti-corrosion, and synergistic antibacterial performance

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2024年第3期17卷 913-926页

作者： Tanlin chen Yingrui Tian Zihao Guo yao chen Qing Qi Fanbin Meng Key Laboratory of Advanced Technologies of Materials(Ministry of Education) School of Materials Science and EngineeringSouthwest Jiaotong UniversityChengdu 610031China Shenzhen Institute of Southwest Jiaotong University Shenzhen 518000China

In order to meet the requirements of the marine environment for microwave absorption(MA)materials,we put forward the strategy of constructing multi-functional composite materials,which integrate microwave absorption,anti-corrosion,and antibacterial ***,graphene oxide(GO)was used as a template to induce the growth of zeolitic imidazolate framework-8(ZIF-8),simultaneously as a two-dimensional(2D)nanocontainers to load corrosion inhibitors to achieve pH-responsive and self-healing ***,quaternary ammonium salt(dimethyl octadecyl(3-trimethoxylsilyl propyl)ammonium chloride(DMAOP))and sodium ascorbate(VCNa)were introduced to achieve synergistic antibacterial activity and the reduction of *** 2D strip-like structure of ZIF-8 was due to the confined growth induced by the electrostatic attraction between ZIF-8 and GO *** as-obtained reduced GO(RGO)/ZIF-8/DMAOP5 exhibited excellent microwave absorption(MA)properties,with a minimum reflection loss(RL)value of-47.08 dB at 12.73 GHz when the thickness was 2.8 ***,the effective absorption bandwidth reached 6.84 *** soaking in 3.5%NaCl solution for 35 days,the RGO/ZIF-8/DMAOP5-0.7%coating still achieved an impedance value of 4.585×107Ω·cm^(2) and a protective efficiency of 99.994%,providing superior anti-corrosion *** addition,fantastic antibacterial activity was obtained,with the antibacterial rates of RGO/ZIF-8/DMAOP_(10) reaching 99.39%and 100%against Escherichia coli and Staphylococcus *** work could open new avenues towards the development of a new generation of multifunctional MA materials.

关键词： two-dimensional(2D)strip-like zeolitic imidazolate framework-8(ZIF-8) microwave absorption active and passive anti-corrosion antibacterial

A symmetric substructuring method for analyzing the natural frequencies of conical origami structures

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Theoretical & Applied Mechanics Letters 2024年第3期14卷 203-210页

作者： chenhao Lu yao chen Weiying Fan Jian Feng Pooya Sareh Key Laboratory of Concrete and Prestressed Concrete Structures of Ministry of Education and National Prestress Engineering Research CenterSoutheast UniversityNanjing 211189China School of Engineering University of LiverpoolLiverpool L693BXUnited Kingdom Creative Design Engineering Lab(Cdel) School of EngineeringNewcastle UniversityNewcastle upon Tyne NE17RUUnited Kingdom Escuela Técnica Superior de Ingeniería y Diseño Industrial Universidad Politécnica de Madrid(UPM)Madrid 28012Spain

Conical origami structures are characterized by their substantial out-of-plane stiffness and *** investigations have commonly focused on the static characteristics of these lightweight ***,the efficient analysis of the natural vibrations of these structures is pivotal for designing conicalorigami structures with programmable stiffness and *** this paper,we propose a novel method to analyzethe natural vibrations of such structures by combining a symmetric substructuring method(SSM)and a gener-alized eigenvalue *** exploits the inherent symmetry of the structure to decompose it into a finiteset of repetitive *** doing so,we reduce the dimensions of matrices and improve computationalefficiency by adopting the stiffness and mass matrices of the substructures in the generalized eigenvalue *** element simulations of pin-jointed models are used to validate the computational results of the ***,the parametric analysis of the structures demonstrates the influences of the number of seg-ments along the circumference and the radius of the cone on the structural mass and natural frequencies of ***,we present a comparison between six-fold and four-fold conical origami structures anddiscuss the influence of various geometric parameters on their natural *** study provides a strategyfor efficiently analyzing the natural vibration of symmetric origami structures and has the potential to contributeto the efficient design and customization of origami metastructures with programmable stiffness.

关键词： Natural structural vibration Origami design Group theory Symmetric substructuring method(SSM) Generalized eigenvalue analysis

Exploring a balance between strength and ductility of hexagonal BN nanoplatelet reinforced ZK61 magnesium composite

在线全文

学校读者我要写书评

暂无评论

Journal of Magnesium and Alloys 2024年第5期12卷 1899-1910页

作者： Kewei Zhang Xiaolong Lu Yufeng Sun Shaokang Guan yao chen School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China Key Laboratory of Advanced Magnesium Alloys in Henan Province Zhengzhou UniversityZhengzhou 450002China Key Laboratory of Advanced Materials Processing&Mold Ministry of EducationZhengzhou 450002China School of Mechanical and Electrical Engineering Soochow UniversitySuzhou 215021China

The practical applications of magnesium(Mg)alloys are usually beset by their relatively low strength and limited *** we attempt to fabricate hexagonal BN nanoplatelet(BNNP)reinforced ZK61 magnesium composites using a combination of spark plasma sintering and friction stir *** resulting composites exhibit microstructural characteristics of homogeneous dispersion of BNNP in Mg matrix with refined equiaxed grains and(0002)basal texture roughly surrounding the pin column *** electron microscopy observation illustrates that trace amounts of Mg_(3)N_(2)and MgB_(2)form at BNNP-Mg interface,in which Mg_(3)N_(2)locates at the basal plane of a BNNP and MgB_(2)grows at its open *** spatial distribution of Mg_(3)N_(2)and MgB_(2)facilitates interfacial wetting and stronger BNNP-Mg interface in such a way that interfacial products act as anchors bonding between *** comparison with monolithic ZK61 alloy,the BNNP/ZK61 composites display simultaneous improvements in yield strength,hardness and ductility,achieving good strength-ductility *** research is expected to shed some light on BNNP potentials for designing and producing magnesium composites with high strength and good ductility.

关键词： BN nanoplatelet Magnesium composite Strength Ductility Spark plasma sintering Friction stir processing

A Confined Two-peaked Solar Flare Observed by EAST and SDO

在线全文

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2024年第4期24卷 71-83页

作者： Liang Zhang Ruisheng Zheng Zhike Xue Changhui Rao Qing Lin Zhimao Du Jiawen yao Libo Zhong yao chen Institute of Space Sciences Shandong UniversityWeihai 264209China Yunnan Key Laboratory of the Solar physics and Space Science Kunming 650011China Institute of Frontier and Interdisciplinary Science.Shandong University Qingdao266237China Institute of Optics and Electronics Chinese Academy of SciencesChengdu 610209China National Laboratory on Adaptive Optics Chengdu610209China University of Chinese Academy of Sciences Beijing 100049China Shanghai Astronomy Museum Shanghai201306China

The solar flare is one of the most violent explosions,and can disturb the near-Earth space *** for commonly single-peaked solar flares in soft X-ray,some special flares show intriguing a two-peak feature that is deserved much more ***,we reported a confined two-peaked solar flare and analyzed the associated eruptions using high-quality observations from Educational Adaptive-optics Solar Telescope and Solar Dynamics *** the flare,a magnetic flux rope(MFR)formed through partially tether-cutting reconnection between two sheared *** flare occurred after the MFR eruption that was confined by the overlying strong ***,a small underlying filament immediately erupted,which was possibly destabilized by the flare *** successive eruptions were confirmed by the analysis of the emission measure and the reconnection ***,we suggest that the two peaks of the confined solar flare are corresponding to two episodes of magnetic reconnection during the successive eruptions of the MFR and the underlying filament.

关键词： Sun:activity Sun:corona Sun:flares Sun:magnetic fields Sun:filaments prominences Online material:animations

d-d Orbital coupling induced by crystal-phase engineering assists acetonitrile electroreduction to ethylamine

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2024年第2期89卷 216-225,I0006页

作者： Honggang Huang yao chen Hui Fu Cun chen Hanjun Li Zhe Zhang Feili Lai Shuxing Bai Nan Zhang Tianxi Liu Key Laboratory of Synthetic and Biological Colloids Ministry of EducationSchool of Chemical and Material EngineeringJiangnan UniversityWuxi 214122JiangsuChina Department of Chemistry KU LeuvenCelestijnenlaan 200FLeuven 3001Belgium College of Chemistry and Chemical Engineering Qingdao UniversityQingdao 266071ShandongChina

The d-d orbital coupling induced by crystal-phase engineering can effectively adjust the electronic structure of electrocatalysts,thus showing significant catalytic performance,while it has been rarely explored in electrochemical acetonitrile reduction reaction(ARR)to ***,we successfully realize the structural transformation of Pd Cu metallic aerogels(MAs)from face-centered cubic(FCC)to body-centered cubic(BCC)through annealing ***,the BCC Pd Cu MAs exhibit excellent ARR performance with high ethylamine selectivity of 90.91%,Faradaic efficiency of 88.60%,yield rate of 316.0 mmol h^(-1)g^(-1)_(Pd+Cu)and long-term stability for consecutive electrolysis within 20 h at-0.55 V *** hydrogen electrode,outperforming than those of FCC Pd Cu *** the membrane electrode assembly system,BCC Pd Cu MAs also demonstrate excellent ethylamine yield rate of 389.5 mmol h^(-1)g^(-1)_(Pd+Cu).Density functional theory calculation reveals that the d-d orbital coupling in BCC Pd Cu MAs results in an evident correlation effect for the interaction of Pd and Cu sites,which boosts up the Cu sites electronic activities to enhance ARR *** work opens a new route to develop efficient ARR electrocatalysts from the perspective of crystalline structure transformation.

关键词： d-d Orbital coupling Crystal-phase engineering Metallic aerogels Acetonitrile electroreduction reaction Ethylamine

Strong metal-support interaction between AuPd nanoparticles and oxygen-rich defect ZrO_(2) for enhanced catalytic 5-hydroxymethylfurfural oxidation

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2024年第2期35卷 507-511页

作者： Yunlei Zhang Yiran Liu Wen Guan Mengxue Cao yao chen Pengwei Huo Institute of Green Chemistry and Chemical Technology School of Chemistry and Chemical EngineeringJiangsu UniversityZhenjiang 212013China School of the Environment and Safety Jiangsu UniversityZhenjiang 212013China

The unique properties of metal oxide surfaces,crystal surfaces and defects play vital roles in biomass upgrading *** this work,hierarchical porous bowl-shaped ZrO_(2)(HB-ZrO_(2))with mixed crystal phase was designed and employed as the support for loading AuPd bimetal with different proportions to synthesize AuPd/HB-ZrO_(2) *** effects of surface chemistry,oxygen defects,bimetal interaction and metal-support interaction of AuPd/HB-ZrO_(2) on catalytic performance for the selective oxidation of 5-hydroxymethylfurfural(HMF)to 2,5-furandicarboxylic acid(FDCA)were systematically *** Au 2 Pd1/HB-ZrO_(2) catalyst afforded a satisfactory FDCA yield of 99.9%from HMF oxidation using O_(2) as the oxidant in water,accompanied with an excellent FDCA productivity at 97.6 mmol g^(−1) h^(−1).This work offers fresh insights into rationally designing efficient catalysts with oxygen-rich defects for the catalytic upgrading of biomass platform chemicals.

关键词： 5-Hydroxymethylfurfural oxidation 2,5-Furandicarboxylic acid Oxygen-rich defect ZrO_(2) AuPd bimetal Bowl-shaped structure

Possible bias of the constraints on the Hubble constant owing to the quasi-Gaussian distribution of DM_(IGM)in fast radio bursts

在线全文

学校读者我要写书评

暂无评论

Chinese Physics C 2024年第7期48卷 211-220页

作者：陈贵垚李昕 Department of Physics Chongqing UniversityChongqing 401331China Chongqing Key Laboratory for Strongly Coupled Physics Chongqing UniversityChongqing 401331China

Fast radio bursts(FRBs)are useful cosmological probes with numerous applications in *** distribution of the dispersion measurement contribution from the intergalactic medium is a key issue.A quasi-Gaussian distribution has been used to replace the traditional Gaussian distribution,yielding promising ***,this study suggests that there may be additional challenges in its *** used 35 well-localized FRBs to constrain the Hubble constant H_(0)along with two FRB-related parameters,yielding H_(0)=■The best-fitting Hubble constant H_(0)is smaller than the value obtained from the Cosmic Microwave Background(CMB),which may be caused by the small sample size of current FRB *** Carlo simulations indicate that a set of 100 simulated FRBs provides a more precise fitting result for the Hubble ***,the precision of the Hubble constant does not improve when further enlarging the FRB *** simulations reveal a systematic deviation in the fitting results of■,attributed to the quasi-Gaussian distribution of the dispersion measure in the intergalactic *** this,the results remain reliable within 1σuncertainty,assuming that a sufficient number of FRB data points are available.

关键词： fast radio bursts Hubble constant cosmological parameters

Spatiotemporal dynamics of the social structure of Indo-Pacific humpback dolphins(Sousa chinensis)in Xiamen waters from 2007 to 2019

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Zoological Research 2024年第2期45卷 439-450页

作者： Yi Lu Xin-Rong Xu Bing-yao chen Thomas A Jefferson Holly Fearnbach Guang Yang Jiangsu Key Laboratory for Biodiversity and Biotechnology College of Life SciencesNanjing Normal UniversityNanjingJiangsu 210023China Clymene Enterprises LakesideCalifornia 92040USA Marine Mammal Research SR3SeaLife ResponseRehabilitation and ResearchWA 98275USA Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) No.1119Haibin RoadNansha DistrictGuangzhouGuangdong 511458China

As highly social animals,Indo-Pacific humpback dolphins(Sousa chinensis)exhibit community ***,our understanding of the external and internal factors influencing these dynamics,as well as their spatiotemporal variations,is still *** the present study,variations in the social structure of an endangered Indo-Pacific humpback dolphin population in Xiamen Bay,China,were monitored over two distinct periods(2007–2010 and 2017–2019)to analyze the effects of habitat utilization and the composition of individuals within the *** both periods,the population demonstrated a strikingly similar pattern of social differentiation,characterized by the division of individuals into two main clusters and one small ***,the two primary clusters occupied the eastern and western waters,respectively,although the core distribution area of the eastern cluster shifted further eastward between the two *** this distribution shift,the temporal stability of the social structure and inter-associations within the eastern cluster remained unaffected.A subset of 16individuals observed in both periods,comprising 51.6%and 43.2%of the population in each respective period,emerged as a foundational element of the social structure and may be responsible for sustaining social structure stability,especially during the 2007–2010 *** observations suggest that the composition of dominant individuals,an internal factor,had a more substantial influence on the formation of the social network than changes in habitat use,an external ***,the study proposes distinct conservation measures tailored to each of the two main clusters.

关键词： Social differentiation Social structure Sousa chinensis Dynamics Conservation