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Pb induced dislocation defects of PtCo systems: Strain-triggered oxygen reduction reaction for PEMFC

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Nano Research 2024年第4期17卷 2462-2472页

作者： chun jin Qiheng Wang jingjun Liu Beijing Key Laboratory of Electrochemical Process and Technology for Materials Beijing 100029China Beijing University of Chemical Technology Beijing 100029China

Design and development of advanced electrocatalysts with high performance and low Pt consumption are crucial for reducing the kinetic energy barrier of the cathode oxygen reduction reaction(ORR)and improving the efficiency of proton exchange membrane fuel cells(PEMFC).In this study,we demonstrate a Pb-modulated PtCo system for efficient ORR,in which the inclusion of Pb in ternary alloys induces dislocation defects due to the significant difference in atomic ***-PtCoPb was confirmed to exhibit significantly higher ORR activity and stability in acidic *** practical PEMFC applications,it outperforms the corresponding commercial Pt/C with a mass activity of 0.58 A·mgPt^(-1),making it a promising alternative to state-of-the-art Pt-based *** combination of experimental results and density functional theory(DFT)calculations offers valuable atomic-level insights into the dislocation *** with a larger atomic radius is located in the lattice stretching region below the dislocation slip plane,forming a structure similar to a Cottrell atmosphere,which reduces the dislocation energy and puts the system in a lower energy *** Cottrell atmosphere pins the dislocation structure and stabilizes the ternary *** adjusting the amount of added Pb,a moderate level of dislocation density induces a tuned strain effect,thereby enhancing the electrocatalytic mechanism by optimizing the electronic structure of the alloy surface and the adsorption and desorption of oxygen *** work provides valuable insights into the design and development of lattice dislocation defect structures to trigger strain effects for improving ORR performance.

关键词： dislocation defect strain effect Pb-modulated oxygen reduction reaction

Flocking of a Cucker–Smale Type Model with Compactly Supported Interaction Functions

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2285-2296页

作者： chun Yin jin Shuang Zhi LI College of Science China Agricultural UniversityBeijing 100083P.R.China

How to analyze flocking behaviors of a multi-agent system with local interaction functions is a challenging problem in *** and Tadmor in 2011 also stressed the significance to assume that the interaction function is rapidly decaying or cut-off at a finite distance(*** and Tadmor in ***.2011).In this paper,we study the flocking behavior of a Cucker–Smale type model with compactly supported interaction *** properties of a connected stochastic matrix,together with an elaborate analysis on perturbations of a linearized system,we obtain a sufficient condition imposed only on model parameters and initial data to guarantee ***,it is shown that the system achieves flocking at an exponential rate.

关键词： Cucker-Smale model local interaction flocking stochastic matrix neighbor graph

Demonstration of Inverse Scattering Transform in G-L-M Formalism for NLS Equation in Normal Dispersion with Non-vanishing Boundary

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Communications in Theoretical Physics 2008年第12期50卷 1375-1380页

作者： YANG chun-Nuan HE jin-chun HUANG Nian-Ning Department of Mathematics Huazhong University of Science and Technology Wuhan 430074 China Department of Physics Wuhan University Wuhan 430072 China

Using the integral representation of the Jost solution,we deduce some conditions as the kernel functionN(x,y,t)if the Jost solution satisfies the two Lax *** we verify the multi-soliton solution of NLS equationwith non-vanishing boundary conditions if we prove that these conditions can be demonstrated by the GLM equation,which determines the kernel function N(x,y,t)in according to the inverse scattering method.

关键词： NLS^+ equation inverse scattering method Gel'fand Levitan Marchenko equation

Ileum perforation due to delayed operation in obturator hernia:A case report and review of literatures

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World Journal of Gastroenterology 2010年第1期16卷 126-130页

作者： Zhang, Hong Cong, jin-chun Chen, chun-Sheng China Med Univ Shengjing Hosp Dept Colorectal Tumor Surg Shenyang 110004 Liaoning Prov Peoples R China

A 83-year-old woman was admitted to our hospital because of intermittent abdominal colicky pain and vomiting for 26 *** pain localized over the periumbilical area with radiation along the medial side of the *** tomography scan with three-dimensional reconstruction revealed a loop of small bowel protruding into the left obturator canal. Incarcerated obturator hernia was diagnosed and emergency laparotomy was arranged immediately. Unfortunately,her family refused surgery because of her worsening *** the third evening after admission,the patient developed peritonitis and sepsis. Perforation of small bowel due to the incarceration was noted during *** resection and an endileostomy were *** recovered well despite of the complication of multiple organ dysfunction *** is reviewed,and the pathogenesis,clinical manifestation,imaging features and treatment are discussed.

关键词： Obturator hernia Intestinal obstruction Computed tomography

Comment on Revision of Kaup-Newell's Works on IST for DNLS Equation

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Communications in Theoretical Physics 2008年第12期50卷 1369-1374页

作者： HE jin-chun CHEN Zong-Yun Department of Mathematics Huazhong University of Science and Technology Wuhan 430074 China Department of Physics Huazhong University of Science and Technology Wuhan 430074 China

In this note, it is shown that the revision of the Kaup-Newell＇s works on 1ST for DNLS equation is only available in the ease of solving the bright one-soliton solution to the equation. An example is taken to illustr... 详细信息

关键词： the DNLS equation inverse scattering method two-soliton solution asymptotic behavior

Magnetic flux participation in solar surface magnetism during solar cycle 24

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Research in Astronomy and Astrophysics 2019年第5期19卷 61-74页

作者： chun-Lan jin jing-Xiu Wang Key Laboratory of Solar Activity National Astronomical Observatories Chinese Academy of Sciences

This study aims at investigating surface magnetic flux participation among different types of magnetic features during solar cycle 24. State-of-the-art observations from SDO/HMI and Hinode/SOT are combined to form a unique database in the interval from April 2010 to October 2015. Unlike previous studies, the statistics presented in this paper are feature-detection-based. More than 20 million magnetic features with relatively large scale, such as sunspot/pore, enhanced and quiet networks, are automatically detected and categorized from HMI observations, and the internetwork features are identified from SOT/SP observations. The total flux from these magnetic features reaches 5.9×10^(22) Mx during solar minimum and2.4 × 10^(23) Mx in solar maximum. Flux occupation from the sunspot/pore region is 29% in solar *** and quiet networks contribute 18% and 21% flux during the solar minimum, and 50% and 9% flux in the solar maximum respectively. The internetwork field contributes over 55% of flux in the solar minimum, and its flux contribution exceeds that of sunspot/pore features in the solar maximum. During the solar active condition, the sunspot field increases its area but keeps constant flux density of about 150 G,while the enhanced network follows the sunspot number variation showing increasing flux density and area,but the quiet network displays decreasing area and somewhat increasing flux density of about 6%. The origin of the quiet network is not known exactly, but is suggestive of representing the interplay between mean-field and local dynamos. The source, magnitude and possible importance of ‘hidden flux' are discussed in some detail.

关键词： Sun:magnetic fields Sun:dynamo Sun:photosphere sunspots

State Estimation of the Electric Drive Articulated Dump Truck Based on UKF

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Journal of Harbin Institute of Technology(New Series) 2015年第6期22卷 21-30页

作者： chun jin Tong Liu Yanhua Shen School of Mechanical Engineering University of Science and Technology Beijing

The requirements of vehicle dynamic stability control are higher than ever as the significant increase of electric drive articulated vehicle speed. According to the construction features of articulated dumping truck and nonlinear characteristics of moving vehicles,nonlinear observer of vehicle status is designed to strength robustness of dynamic control system in this paper. A 4-degree-of-freedom nonlinear dynamic model of articulated electric drive vehicle is built as reference model to estimate the state of the articulated vehicle. And by adopting Unscented Kalman Filter( UKF) algorithm,a series of state parameters such as longitudinal velocities of front and rear frames,yaw rate and side-slip angle are estimated. During the test of 60 t articulated electric drive vehicle,2 inertial navigation modules are installed in the front frame and rear frame respectively and the speed of each electric drive wheel is obtained simultaneously. As the test results suggest,in various working conditions,the algorithm based on UKF is able to accurately estimate the state parameters of articulated vehicle with the estimated error less than 5%. The proposed method is justified to be the theoretical basis and application guidance for articulated vehicle stability control.

关键词： articulated dump trucks nonlinear observer soft measurement Unscented Kalman Filter sideslip angle

Intestinal microbiota in the treatment of metabolically associated fatty liver disease

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World Journal of Clinical Cases 2022年第31期10卷 11240-11251页

作者： Ji-Shuai Wang jin-chun Liu Shanxi Medical University Taiyuan 030001Shanxi ProvinceChina Department of Gastroenterology The First Hospital of Shanxi Medical UniversityTaiyuan 030001Shanxi ProvinceChina

Metabolically associated fatty liver disease (MAFLD) is a common cause ofchronic liver disease, the hepatic manifestation of metabolic syndrome. Despitethe increasing incidence of MAFLD, no effective treatment is available. Recentresearch indicates a link between the intestinal microbiota and liver diseases suchas MAFLD. The composition and characteristics of the intestinal microbiota andtherapeutic perspectives of MAFLD are reviewed in the current study. Animbalance in the intestinal microbiota increases intestinal permeability andexposure of the liver to adipokines. Furthermore, we focused on reviewing thelatest "gut-liver axis" targeted therapy.

关键词： Intestinal microbiota Metabolically associated fatty liver disease Gut-liver axis Adipokines Therapy

Interaction between granulation and small-scale magnetic flux observed by Hinode

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Research in Astronomy and Astrophysics 2009年第8期9卷 921-932页

作者： Jun Zhang Shu-Hong Yang chun-Lan jin Key Laboratory of Solar Activity National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China

With the polarimetric observations obtained by the Spectro-Polarimeter on board Hinode, we study the relationship between granular development and magnetic field evolution in the quiet Sun. Six typical cases are displayed to exhibit interaction between granules and magnetic elements, and we have obtained the following results. （1） A granule develops centrosymmetrically when no magnetic flux emerges within the granular cell. （2） A granule develops and splits noncentrosymmetrically while flux emerges at an outer part of the granular cell. （3） Magnetic flux emergence in a cluster of mixed polarities is detected at the position of a granule as soon as the granule breaks up. （4） A dipole emerges accompanied by the development of a granule, and the two elements of the dipole are rooted in the adjacent intergranular lanes and face each other across the granule. Advected by the horizontal granular motion, the positive element of the dipole then cancels with the pre-existing negative flux. （5） Flux cancellation also takes place between a positive element, which is advected by granular flow, and its surrounding negative flux. （6） While magnetic flux cancellation takes place in a granular cell, the granule shrinks and then disappears. （7） Horizontal magnetic fields are enhanced at the places where dipoles emerge and where opposite polarities cancel each other, but only the horizontal fields between the dipolar elements point in an orderly way from the positive elements to the negative ones. Our results reveal that granules and small-scale magnetic fluxes influence each other. Granular flow advects magnetic flux, and magnetic flux evolution suppresses granular development. There exist extremely large Doppler blue-shifts at the site of one canceling magnetic element. This phenomenon may be caused by the upward flow produced by magnetic reconnection below the photosphere.

关键词： Sun granulation -- Sun magnetic fields -- Sun photosphere-- techniques polarimetric