检索结果-南通市图书馆

Nano Research 2024年第9期17卷 8627-8637页

作者： Shan-Fei Wang Yangyang li Haiyan Wang Jin-xia liang Chun Zhu Botao Qiao School of Chemistry and Chemical Engineering Guizhou UniversityGuiyang 550025China CAS Key Laboratory of Science and Technology on Applied Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China University of Chinese Academy of Sciences Beijing 100049China

Oxide-supported metal single-atom catalysts(SACs)have exhibited excellent catalytic performance for water-gas shift(WgS)***,we report the single-atom catalyst Pt1/FeOx exhibits excellent medium temperature catalytic performance for WgS reactions by the density functional theory(DFT)calculations and experimental *** calculations indicate that H_(2)O molecules are easily dissociated at oxygen vacancies,and the formed*OH and*O are adsorbed on Pt1 single atoms and the adjacent O atoms,*** studying four possible reaction mechanisms,it is found that the optimal WgS reaction pathway is proceeded along the carboxyl mechanism(pathway III),in which the formation of*COOH intermediates can promote the stability of Pt1/FeOx SAC and the easier occurrence of WgS *** energy barrier of the rate-determining step during the entire reaction cycle is only 1.16 eV,showing the high activity for the medium temperature WgS reaction on Pt1/FeOx SAC,which was verified by experimental ***,the calculated turnover frequencies(TOFs)of CO_(2)and H_(2)formation on Pt1/FeOx at 610 K(337℃)can reach up to 1.14×10^(-3)s^(-1)·site^(-1)through carboxyl *** this work,we further expand the application potential of Pt1/FeOx SAC in WgS reaction.

关键词： water-gas shift(WgS)reaction single-atom catalyst(SAC) density functional theory(DFT) thermocatalysis

A regularization algorithm of dynamic light scattering for estimating the particle size distribution of dual-substance mixture in water

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Particuology 2024年第6期89卷 246-257页

作者： Yanghong Wang Ziqiang Meng Zipei Zhang Min xia li xia Wei li School of Optical and Electronic Information Huazhong University of Science and TechnologyWuhan 430074China

Dynamic light scattering(DLS)is a nondestructive,well-established technique for the size characterization of proteins,nanoparticles,polymers,and colloidal ***,current DLS techniques are only applied to particle groups of single composition due to the limitation of their inversion *** this study,we propose a particle size distribution inversion algorithm based on the Tikhnonov regularization method that can be applied to the dual-substance particle *** algorithm retrieves the particle size distributions of two substances,respectively,by taking advantage of their refractive index *** simulation results reveal that the algorithm has excellent accuracy and stability when the scattering angle is 30°.Instead of the original identity matrix,the first-order difference matrix and second-order difference matrix are used as the regular matrix when utilizing the Tikhnonov algorithm,which obviously improves the anti-interference,accuracy,and stability of the ***,the inversion of particle size distribution is carried out at a 0.01%–1%noise level,which shows that the algorithm has an available antinoise ***,experimental particle size measurements for a mixture of polystyrene beads and toner particles demonstrate that the proposed algorithm is superior to the traditional Tikhnonov algorithm in applicability and accuracy.

关键词： Dynamic light scattering Dual-substance mixture Particle sized istribution Tikhnonov regularization

Seedless Synthesis of gold Nanorods with 5–10 nm in Diameters:a Comprehensive Study

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 2024年第2期40卷 311-319页

作者： li Yalan xia Yunsheng Anhui Province Key Laboratory of Biomedical Materials and Chemical Measurement Key Laboratory of Functional Molecular SolidsMinistry of EducationCollege of Chemistry and Materials ScienceAnhui Normal UniversityWuhu241000P.R.China

Small gold nanorods(AuNRs),namely AuNRs with less than 10 nm in diameter,possess a high absorption-to-scattering ratio,a large surface area-to-volume ratio,as well as high cellular uptake *** this study,we systematically investigate seedless synthesis of AuNRs with diameters ranging from 5 nm to 10 *** has been found that several experimental conditions,including the chain length of the used cationic surfactants,and the concentrations of ascorbic acid,NaBH4,and AgNO_(3)can profoundly affect the obtained *** optimal conditions,the production yields of the obtained several AuNRs with different diameters can exceed 90%and even reach almost 100%.The conversion of gold precursors to AuNRs was estimated to be 70%–77%as measured by absorption spectroscopy and inductively coupled plasma mass spectrometry.

关键词： Small gold nanorod Diameter Production yield Conversion rate

Synergy effect of regulated li-plating and functional solid electrolyte interphase on graphite anodes

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9期17卷 8077-8085页

作者： Panpan Wang Baojia xia Jianling li State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China Shanghai Institute of Microsystem and Information Technology Chinese Academy of SciencesShanghai 201800China

The growth of li dendrites poses potential safety hazard to lithium-ion batteries(liBs),and eliminating li dendrites thoroughly stills face tough difficulties ***,regulating li-plating is a critical optimization-direction to address the ***,a“graphite-li hybrid”anode with high reversibility is realized under the constant-capacity lithiation(CCL).Within CCL,the uniform distribution of li-plating on the graphite surface is successfully *** evolution in different states of solid electrolyte interphase(SEI)is investigated in detail to study the interaction between the potentials and impedance during the process of liintercalation and *** the potential below 0 V and the state of charge(SOC)of 110%relative to the theoretical capacity,the F-rich SEI with high stability is constructed to hinder the emergency of li dendrites and maintain the intact structure of graphite anode under long *** cell presents more than 100%Coulombic efficiency(CE)with the 900 cycles,demonstrating the reversible li-plating and the utilization of *** the CCL half-cell provides a good cycling performance and specific capacity of 900 cycles at 0.5 C,it is attributed to the synergy effect of stable inorganic-rich SEI and regulated active li-plating.

关键词： "graphite-li hybrid"anode li-plating reversibility solid electrolyte interphase(SEI)

Prediction and scheduling of multi-energy microgrid based on BigRU self-attention mechanism and LQPSO

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

global Energy Interconnection 2024年第3期7卷 347-361页

作者： Yuchen Duan Peng li Jing xia School of Automation and Intelligence Beijing Jiaotong UniversityBeijing 100044P.R.China goldwind Science&Technology Co.Ltd. Beijing 100176P.R.China

To predict renewable energy sources such as solar power in microgrids more accurately,a hybrid power prediction method is presented in this ***,the self-attention mechanism is introduced based on a bidirectional gated recurrent neural network(BigRU)to explore the time-series characteristics of solar power output and consider the influence of different time nodes on the prediction ***,an improved quantum particle swarm optimization(QPSO)algorithm is proposed to optimize the hyperparameters of the combined prediction *** final proposed LQPSO-BigRU-self-attention hybrid model can predict solar power more *** addition,considering the coordinated utilization of various energy sources such as electricity,hydrogen,and renewable energy,a multi-objective optimization model that considers both economic and environmental costs was constructed.A two-stage adaptive multi-objective quantum particle swarm optimization algorithm aided by a Lévy flight,named MO-LQPSO,was proposed for the comprehensive optimal scheduling of a multi-energy microgrid *** algorithm effectively balances the global and local search capabilities and enhances the solution of complex nonlinear *** effectiveness and superiority of the proposed scheme are verified through comparative simulations.

关键词： Microgrid Bidirectional gated recurrent unit Self-attention Lévy-quantum particle swarm optimization Multi-objective optimization

Modifying Lyapunov exponent of chaotic map by self-cascading

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2024年第7期67卷 2203-2214页

作者： YI ChenLong li ChunBiao li YongXin xia Ming HUA ZhongYun School of Electronic and Information Engineering Nanjing University of Information Science&TechnologyNanjing 210044China School of Artificial Intelligence Nanjing University of Information Science&TechnologyNanjing 210044China School of Computer Science and Technology Harbin Institute of Technology Shenzhen Graduate SchoolShenzhen 518055China

The self-cascade(SC) method is an effective technique for chaos enhancement and complexity increasing in chaos ***, the controllable self-cascade(CSC) method allows for more accurate control of Lyapunov exponents of the discrete map. In this work, the SC and CSC systems of the original map are derived, which enhance the chaotic performance while preserving the fundamental dynamical characteristics of the original map. Higher Lyapunov exponent of chaotic sequences corresponding to higher frequency are obtained in SC and CSC systems. Meanwhile, the Lyapunov exponent could be linearly controlled with greater flexibility in the CSC system. The verification of the numerical simulation and theoretical analysis is carried out based on the platform of CH32.

关键词： self-cascade controllable self-cascade chaos enhancement chaos control

同方期刊数据库

Microbiome changes in esophageal cancer:implications for pathogenesis and prognosis

在线全文

学校读者我要写书评

暂无评论

Cancer Biology & Medicine 2024年第2期21卷 163-174页

作者： Yi li Bing Wei xia Xue Hongle li Jun li Department of Molecular Pathology Clinical Pathology CenterAffiliated Cancer Hospital of Zhengzhou University and Henan Cancer HospitalZhengzhou 450003China Henan Key Laboratory of Molecular Pathology Zhengzhou 450003China Henan Key Laboratory of Helicobacter pylori&Microbiota and gastrointestinal Cancer Marshall Medical Research CenterThe Fifth Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052China

Esophageal cancer(EC)is an aggressive malignancy with a poor *** factors,including dietary habits,and antacid and antibiotic use,have been shown to influence the esophageal ***,enrichment and diversity of the esophageal microbiome can also impact its *** studies have revealed prevalent changes in the esophageal microbiome among patients with EC,thus suggesting the potential contribution of the esophageal microbiome to EC ***,distinct microbiome compositions have been observed in patients with different responses to radiotherapy and chemotherapy,indicating the role of the esophageal microbiome in modulating treatment *** this review,we have examined previous studies on the esophageal microbiome in healthy individuals and patients with EC or other esophageal diseases,with a focus on identifying microbial communities associated with EC pathogenesis and *** the role of the microbiome in EC may aid in early detection and optimized treatment strategies,ultimately leading to better outcomes for patients.

关键词： Esophageal cancer microbiome dysbiosis microenvironment carcinogenesis

Heteroepitaxial growth of Au@Pd core–shell nanocrystals with intrinsic chiral surfaces for enantiomeric recognition

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2024年第1期43卷 225-235页

作者： Feng-xia Wu Feng-Hua li xia-li Lv Qi-xian Zhang guo-Bao Xu Wen-Xin Niu State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Shaoxing Institute of Technology Shanghai UniversityShaoxing 312000China University of Science and Technology of China Hefei 230026China School of Materials Science and Engineering Shanghai UniversityShanghai 200436China Zhejiang Institute of Advanced Materials Shanghai UniversityJiashan 314113China University of Chinese Academy of Sciences Beijing 100039China

Noble metal surfaces with intrinsic chirality serve as an ideal candidate for investigating enantioselective chemistry due to their superior chemical durability and high catalytic ***,significant advance has been made in synthesizing metal nanocrystals with intrinsic ***,the majority reports are limited to ***,through a heteroepitaxial growth strategy,the synthesis of metal nanocrystals with intrinsic chirality to palladium was extended for the first time and their application in enantioselective recognition was *** heteroepitaxial growth strategy allows for transferring the chirality of homochiral Au nanocrystals to Au@Pd core–shell *** employing the chiral Au@Pd nanocrystals as enantiomeric recognizing elements,a series of electrochemical sensors for chiral discrimination were *** optimal conditions,the peak potential between D-dihydroxyphenylalanine(D-DOPA)and L-dihydroxyphenylalanine(L-DOPA)is about 80 m V,and the peak current of D-DOPA is 2 times as much as that of L-DOPA,which enables the determination of the enantiomeric excess(EE,%)of ***,this report not only introduces a heteroepitaxial growth strategy to synthesize metal nanocrystals with intrinsic chirality,but also demonstrates the superior capability of integrating intrinsic chirality and catalytic properties into metal nanocrystals for chiral recognition.

关键词： Core–shell nanostructures Chirality transfer Electrochemical sensors Chiral recognition Chiroplasmonics

Towards imbalanced motion:part-decoupling network for video portrait segmentation

在线全文

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2024年第7期67卷 197-210页

作者： Tianshu YU Changqun xia Jia li State Key Laboratory of Virtual Reality Technology and Systems School of Computer Science and EngineeringBeihang University Peng Cheng Laboratory

Video portrait segmentation(VPS), aiming at segmenting prominent foreground portraits from video frames, has received much attention in recent years. However, the simplicity of existing VPS datasets leads to a limitation on extensive research of the task. In this work, we propose a new intricate large-scale multi-scene video portrait segmentation dataset MVPS consisting of 101 video clips in 7 scenario categories,in which 10843 sampled frames are finely annotated at the pixel level. The dataset has diverse scenes and complicated background environments, which is the most complex dataset in VPS to our best *** the observation of a large number of videos with portraits during dataset construction, we find that due to the joint structure of the human body, the motion of portraits is part-associated, which leads to the different parts being relatively independent in motion. That is, the motion of different parts of the portraits is imbalanced. Towards this imbalance, an intuitive and reasonable idea is that different motion states in portraits can be better exploited by decoupling the portraits into parts. To achieve this, we propose a part-decoupling network(PDNet) for VPS. Specifically, an inter-frame part-discriminated attention(IPDA)module is proposed which unsupervisedly segments portrait into parts and utilizes different attentiveness on discriminative features specified to each different part. In this way, appropriate attention can be imposed on portrait parts with imbalanced motion to extract part-discriminated correlations, so that the portraits can be segmented more accurately. Experimental results demonstrate that our method achieves leading performance with the comparison to state-of-the-art methods.

关键词： video portrait segmentation imbalanced motion unsupervised part decoupling motion correlation inter-frame attention

同方期刊数据库

Evolution of inner wall wrinkle defects in the sinking zone of a thick-walled steel tube during radial forging

在线全文

学校读者我要写书评

暂无评论

Advances in Manufacturing 2024年第2期12卷 396-408页

作者： Yu-Zhao Yang Cheng Xu li-xia Fan School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094People’s Republic of China

An axial wrinkle defect was observed in the inner wall of the sinking zone of a thick-wall steel tube processed by cold radial *** can evolve into *** present study focuses on the evolution of wrinkles and the effects of process parameters on them using a three-dimensional radial forging process finite element model,radial forging experiments,and surface morphology *** results indicated that the vertical section angle of the hammer die and the size of the tube blank significantly affect the evolution of *** height-to-width ratioλwas introduced to describe the morphology of *** had an approximately linear relationship with the radius reduction in the sinking *** was a linear correlation between the growth slope ofλand the axial to circumferential strain ratio|εr/εθ|,which can predict theλunder few process *** the 30SiMn2MoVA steel,at the junction of the forging and sinking zones,the threshold ofλof the wrinkle that can evolve into a fissure is approximately 1.123.

关键词： Radial forging Inner wall Wrinkle defects Evolution Sinking zone