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Journal of Materials Science & Technology 2020年第9期44卷 229-236页

作者： Liang Chen Zhi Li Gangyong Li Minjie Zhou Binhong He jie Ouyang Wenyuan Xu Wei wang Zhaohui Hou School of Chemistry and Chemical Engineering Hunan Institute of Science and TechnologyYueyang414006China State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing100083China

Uniform Fe3 C/N-doped carbon nanofibers were successfully synthesized through a facile self-catalyzed CVD method by using acetylene as carbon source and Fe3O4 as iron source and autocatalytic template for the reaction under moderate preparation conditions. The experimental and theoretical calculation results demonstrate that Fe3 C can improve the lithium storage performance of carbon nanofibers. Besides, the addition of PPy can not only control the growth rate of carbon fibers but also help to form uniform carbon fibers. As a result, the obtained Fe3 C/N-doped carbon nanofiber composites display favorable electrochemical performance as an anode for lithium-ion batteries, which including satisfactory rate performance of 402 m A h g-1 under 1.2 Ag-1, and good cycling stability of 502.3 m A h g-1 under 200 m Ag-1 over 400 cycles. The introduction of Fe3 C species and the uniform carbon fiber morphology are responsible for the long-cycling and high rate performance of materials.

关键词： Self-catalyzed CVD Fe3C N-doped carbon fibers Anode materials Lithium-ion batterie

Effects of channel noise on synchronization transitions in delayed scale-free network of stochastic Hodgkin–Huxley neurons

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Chinese Physics B 2015年第11期24卷 619-625页

作者：王宝英龚玉兵 Library Ludong University Yantai 264025 China School of Physics and Optoelectronic Engineering Ludong University Yantai 264025 China

We numerically study the effect of the channel noise on the spiking synchronization of a scale-free Hodgkin-Huxley neuron network with time delays. It is found that the time delay can induce synchronization transitions at an intermediate and proper channel noise intensity, and the synchronization transitions become strongest when the channel noise intensity is optimal. The neurons can also exhibit synchronization transitions as the channel noise intensity is varied, and this phenomenon is enhanced at around the time delays that can induce the synchronization transitions. It is also found that the synchronization transitions induced by the channel noise are dependent on the coupling strength and the network average degree, and there is an optimal coupling strength or network average degree with which the synchronization transitions become strongest. These results show that by inducing synchronization transitions, the channel noise has a big regulation effect on the synchronization of the neuronal network. These findings could find potential implications for the information transmission in neural systems.

关键词： channel noise scale-free network time delay synchronization transition

Study on Volume Variation and Stability of Riverbed in the Yangtze Estuary

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China Ocean Engineering 2023年第3期37卷 433-446页

作者： DING Lei JIAO Jian TONG Chao-feng wang Yi-fei CHEN Ben SUN jie-ying DOU Xi-ping Key Laboratory of Port Waterway and Sedimentation Engineering of MOTNanjing Hydraulic Research InstituteNanjing 210029China College of Harbour Coastal and Offshore EngineeringHohai UniversityNanjing 210098China State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan UniversityChengdu 610065China

In recent years,regional floods and typhoons have occurred in the Yangtze *** dynamic conditions and dramatic reduction of sediment discharge in the basin are affecting the dynamic equilibrium pattern of the Yangtze *** on the field measurement data and theoretical derivation,this paper analyzed the changing process of runoff-sediment discharge into the sea after the operation of the Three Gorges Project(TGP),and the tidal dynamics and sediment variation characteristics of the Yangtze *** erosion of South Branch mainly occurs in the channel below-10 m contour,and the riverbed volume below contours 0 m and-10 m has a good correlation with the sediment discharge of Datong Station in the previous *** this basis,the ratio of the horizontal distance from the starting point to the section centroid below the average water level(B_c)and the water depth at the section centroid(H_c)was proposed to describe the change of the section *** relationships between the water-diverting ratio,the sediment-diverting ratio and the water-diverting angle,the conditions of runoff and sediment discharge from the upper reach and the characteristics of the riverway section were established,and the theoretical calculation equations of the water-diverting ratio,the sediment-diverting ratio and the diverting angle of each bifurcation were also established.

关键词： Yangtze Estuary volume variation section shape riverbed stability

Exploration of Gas-Dependent Self-Adaptive Reconstruction Behavior of Cu₂O for Electrochemical CO₂ Conversion to Multi-Carbon Products

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NANO-MICRO LETTERS 2025年第1期17卷 1-17页

作者： Zhang, Chaoran Gu, Yichuan Jiang, Qu Sheng, Ziyang Feng, Ruohan wang, Sihong Zhang, Haoyue Xu, Qianqing Yuan, Zijian Song, Fang Shanghai Jiao Tong Univ Sch Mat Sci & Engn State Key Lab Met Matrix Composites Shanghai 200240 Peoples R China

Structural reconstruction of electrocatalysts plays a pivotal role in catalytic performances for CO2 reduction reaction (CO2RR), whereas the behavior is by far superficially understood. Here, we report that CO2 accessibility results in a universal self-adaptive structural reconstruction from Cu2O to Cu@CuxO composites, ending with feeding gas-dependent microstructures and catalytic performances. The CO2-rich atmosphere favors reconstruction for CO2RR, whereas the CO2-deficient one prefers that for hydrogen evolution reaction. With the assistance of spectroscopic analysis and theoretical calculations, we uncover a CO2-induced passivation behavior by identifying a reduction-resistant but catalytic active Cu(I)-rich amorphous layer stabilized by *CO intermediates. Additionally, we find extra CO production is indispensable for the robust production of C2H4. An inverse correlation between durability and FECO/FEC2H4 is disclosed, suggesting that the self-stabilization process involving the absorption of *CO intermediates on Cu(I) sites is essential for durable electrolysis. Guided by this insight, we design hollow Cu2O nanospheres for durable and selective CO2RR electrolysis in producing C2H4. Our work recognizes the previously overlooked passivation reconstruction and self-stabilizing behavior and highlights the critical role of the local atmosphere in modulating reconstruction and catalytic processes.

关键词： CO2 reduction reaction Electrocatalysts Cu2O Reconstruction Self-adaptive electrocatalysis

Recent advances in asymmetric synthesis with CO2

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Science China Chemistry 2020年第10期63卷 1336-1351页

作者： Chuan-Kun Ran Xiao-wang Chen Yong-Yuan Gui jie Liu Lei Song Ke Ren Da-Gang Yu College of Chemistry and Materials Science Sichuan Normal UniversityChengdu 610068China Key Laboratory of Green Chemistry&Technology of Ministry of Education College of ChemistrySichuan UniversityChengdu 610064China

Carbon dioxide(CO2)is an important and appealing C1 building block in chemical synthesis due to its nontoxicity,abundance,availability and *** progress has been achieved in the chemical transformation of CO2 into high valueadded organic ***,the asymmetric synthesis with CO2 to form enantioenriched molecules,especially the catalytic process,has lagged far *** enantioselective incorporation of CO2 into organic compounds is highly desirable,as the corresponding chiral products,such as carboxylic acids and amino acids,are common structural units in a vast array of natural products and biologically active ***,we discuss recent progress toward the enantioselective incorporation of CO2 into organic molecules,which mainly rely on three strategies:1)kinetic resolution or desymmetrization of epoxides with CO2 to form chiral cyclic carbonates and polycarbonates;2)nucleophilic attack of O-or N-nucleophiles to CO2 in tandem with asymmetric C–O bond formation to prepare chiral cyclic carbonates and carbamates;3)direct enantioselective nucleophilic attack of organometallic reagents to CO2 with asymmetric C–C bond ***,challenges and future outlook in this area are also presented.

关键词： carbon dioxide asymmetric catalysis carbonate carbamate carboxylic acid

Enhancing charge storage of O-doped perovskite fluorides via in-situ electrochemical oxidation for high-performance potassium-ion capacitors

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Journal of Materials Science & Technology 2023年第27期158卷 111-120页

作者： Jing Zhao Zicheng Cai Yue Fan Yunan wang Yu Song jie Liu Shuangwen Li Di Guo Xiaoxia Liu Department of Chemistry Northeastern UniversityShenyang 110819China School of Resources and Civil Engineering Northeastern UniversityShenyang 110819China National-local Joint Engineering Research Center of High-efficient Exploitation Technology for Refractory Iron Ore Resources Shenyang 110819China School of Materials Engineering North China Institute of Aerospace EngineeringLangfang 065000China

Potassium ion capacitors(PICs)are regarded as promising large-scale aqueous energy storage ***,due to the poor K^(+)transport kinetics and the structural instability of the cathode materials,the key issues of limited energy density and poor cyclic stability are obstacles to the in-depth growth of ***,a novel O-doped perovskite fluoride is demonstrated via an in-situ electrochemical oxidation strategy as the cathode for PICs,introducing additional defects that improve the capacitance and facilitate the reaction kinetics of the *** the electrochemical oxidation process,it is discovered that the perovskite fluoride crystal tends to transform into disordered O-doped KMnF 3(K_(x)MnF_(y)O_(z)),realizing a structural reconstruction at the electrode material/electrolyte *** First-principles calculations based on density functional theory(DFT)are performed to confirm that the improved electrical conduc-tivity and low ionic adsorption energy may be ascribed to the substitution of oxygen for *** obtained K_(1.14)MnF_(1.17)O_(1.26) cathode achieves a high specific capacitance of 694 F g^(-1) at 1 A g^(-1),as well as high capacitance retention of 91.3%after 10,000 charge/discharge cycles in mild K_(2)SO_(4) *** study provides an effective strategy to improve the capacitive performance of perovskite fluoride cathode materials in electrochemical energy storage.

关键词： Perovskite fluorides O-doped Potassium-ion capacitors Charge storage mechanism

Influence of pH on the Formation, Composition and Protectiveness of Fluoride Conversion Film Deposited on AZ31 Magnesium Alloy in KF Solution

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Acta Metallurgica Sinica(English Letters) 2023年第9期36卷 1397-1408页

作者： Liping Wu Chen Liu jie Wei Junhua Dong Lin Zhao Chao Li Wei Ke Yiqing Chen Changgang wang Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang110016China State Key Laboratory of Metal Material for Marine Equipment and Application Anshan114009China

In deaerated 0.1 M KF solution at pH 5, pH 7.5 and pH 9, fluoride films were deposited on AZ31 magnesium (Mg) alloy at − 1.4 V vs saturated calomel electrode (SCE). The morphology, phase composition, elemental and compositional depth distribution of different fluoride films and their influences on the corrosion resistance of AZ31 Mg alloy were explored in detail. The results indicated that the films deposited at weak acidic and nearly neutral pH consisted of two layers with amorphous Mg(OH)_(2) and MgF_(2) as the inner layer, and Mg(OH)_(2), MgF_(2) and KMgF_(3) crystals the outer layer. The film deposited at alkaline pH was a monolayer structure consisting of amorphous Mg(OH)_(2) as the major constitute and MgF_(2) as the minor constitute. The protectiveness of fluoride film was intimately related to its composition and structure. The content and crystal regularity of KMgF_(3) were the two main factors influencing the protectiveness of fluoride film. The fluoride film deposited at pH 7.5 offered the best protection to AZ31 Mg alloy.

关键词： Magnesium alloy Potentiostatic deposition Fluoride film KF solution

Light Emission and Dynamic Failure Mechanism of Hypervelocity Impact on Zr-Ti-Ni-Cu-Be Bulk Metallic Glass

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Chinese Physics Letters 2011年第9期28卷 201-204页

作者： SUN bao-Ru ZHAN Zai-Ji LIANG Bo ZHANG Rui-Jun wang Wen-Kui State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004

Hypervelocity impact on rectangular plate-shaped Zr41Ti14Cu12.5Ni10Be22.5 bulk metallic glass(BMG)is performed by a two−stage light gas *** targets used in the experiment are BMG plates with a thickness of 5 *** projectile,spherical aluminum(3.1 mm in diameter),is accelerated up to various velocities;the light is detected with a *** emission lasts from 200µs up to 1500µs and the intensity increases from 44 to 900 W/(Sr⋅µm).The duration and intensity of a light emission seem to depend on the impact velocity and the extent of target destruction through the formation of impact craters or penetration.

关键词： Impact impact shaped

Spatially distributed cytokinins:Metabolism,signaling,and transport

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Plant Communications 2024年第7期5卷 52-67页

作者： Jiangzhe Zhao Jingqi wang jie Liu Penghong Zhang Guzel Kudoyarova Chang-Jun Liu Kewei Zhang Zhejiang Provincial Key Laboratory of Biotechnology on Specialty Economic Plants College of Life SciencesZhejiang Normal UniversityJinhuaZhejiang 321004P.R.China Ufa Institute of Biology Ufa Federal Research CenterRASProspekt Oktyabrya 69Ufa 450054Russia Biology Department Brookhaven National LaboratoryUptonNY 11973USA

Cytokinins are mobile phytohormones that regulate plant growth,development,and environmental *** major cytokinin species include isopentenyl adenine(iP),trans-zeatin(tZ),cis-zeatin(cZ),and dihydrozeatin(DZ).The spatial distributions of different cytokinin species in different organelles,cells,tissues,and organs are primarily shaped by biosynthesis via isopentenyltransferases(IPT),cytochrome P450 monooxygenase,and 50-ribonucleotide phosphohydrolase and by conjugation or catabolism via glycosyltransferase or cytokinin oxidase/*** bind to histidine receptor kinases in the endoplasmic reticulum or plasma membrane and relay signals to response regulators in the nucleus via shuttle proteins known as histidine phosphotransfer *** movements of cytokinins from sites of biosynthesis to sites of signal perception usually require long-distance,intercellular,and intracellular *** the past decade,ATP-binding cassette(ABC)transporters,purine permeases(PUP),AZA-GUANINE RESISTANT(AZG)transporters,equilibrative nucleoside transporters(ENT),and Sugars Will Eventually Be Exported transporters(SWEET)have been characterized as involved in cytokinin transport *** review begins by introducing the spatial distributions of various cytokinins and the subcellular localizations of the proteins involved in their metabolism and *** focus on an inventory of the characterized transporters involved in cytokinin compartmentalization,including long-distance,intercellular,and intracellular transport,and the regulation of the spatial distributions of cytokinins by environmental *** directions for cytokinin research are also discussed.

关键词： cytokinin biosynthesis transporter signal transduction environmental changes

Role of alloying and heat treatment on microstructure and mechanical properties of cast Al-Li alloys:A review

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China Foundry 2024年第5期21卷 445-460页

作者： Guo-hua Wu You-jie Guo Fang-zhou Qi Shen Zhang Yi-xiao wang Xin Tong Liang Zhang School of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Due to the prominent advantages of low density,high elastic modulus,high specific strength and specific stiffness,cast Al-Li alloys are suitable metallic materials for manufacturing complex large-sized components and are ideal structural materials for aerospace,defense and military *** the basis of the microstructural characteristics of cast Al-Li alloys,exploring the role of alloying and micro-alloying can stabilize their dominant position and further expand their application *** this review,the development progress of cast Al-Li alloys was summarized *** to the latest research highlights,the influence of alloying and heat treatment on the microstructure and mechanical properties was systematically *** potential methods to improve the alloy performance were *** response to the practical engineering requirements of cast Al-Li alloys,the scientific challenges and future research directions were discussed and prospected.

关键词： cast Al-Li alloy alloying microstructure mechanical properties heat treatment