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Chinese Chemical Letters 2016年第4期27卷 597-601页

作者： Jie Wang Ze-Xing Wu Li-Li Han Yuan-Yang Liu jun-po guo Huolin L.Xin De-Li Wang Key Laboratory of Material Chemistry for Energy Conversion and Storage (Huazhong University of Science and Technology) Ministry of Education Hubei Key Laboratory of Material Chemistry and Service Failure School of Chemistry and Chemical Engineering Huazhong University of Science and Technology Center for Functional Nanomaterials Brookhaven National Laboratory School of Materials Science and Engineering Tianjin University

In the present work, we report nitrogen and phosphorus co-doped 3-D structured carbon nanotube intercalated graphene nanoribbon composite. The graphene nanoribbons are prepared via partial exfoliation of multi-walled carbon nanotubes. In the graphene nanoribbons/CNTs composite, carbon nanotubes play a role of skeleton and support the exfoliated graphene nanoribbons to form the stereo structure. After high temperature heat-treatment with ammonium dihydrogen phosphate, the unique structure reserves both the properties of carbon nanotube and graphene, exhibiting excellent catalytic performance for the ORR with excellent onset and half-wave potential, which is similar to commercial Pt/C electrocatalysts.

关键词： Graphene nanoribbons Carbon nanotube Doping Electrocatalyst Oxygen reduction reaction

Systematical identification of regulatory GPCRs by single-cell trajectory inference reveals the role of ADGRD1 and GPR39 in adipogenesis

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Science China Life Sciences 2025年

作者： Chuan Ye Xuemei Wang jun Lin Chenyang Wu Yuhua Gao Chenghao guo Yunxi Liao Ziyan Rao Shaodong Huang Weixuan Chen Ying Huang Jinpeng Sun Dongyu Zhao Changtao Jiang Center of Basic Medical Research Institute of Medical Innovation and ResearchPeking University Third Hospital Department of Physiology and Pathophysiology School of Basic Medical SciencesPeking University Department of Biomedical Informatics School of Basic Medical SciencesPeking University State Key Laboratory of Vascular Homeostasis and Remodeling Peking University Center for Obesity and Metabolic Disease Research School of Basic Medical SciencesPeking University State Key Laboratory of Female Fertility Promotion Center for Reproductive MedicineDepartment of Obstetrics and GynecologyPeking University Third Hospital National Clinical Research Center for Obstetrics and Gynecology Peking University Third Hospital Department of Endocrinology and Metabolism Peking University Third Hospital Key Laboratory Experimental Teratology of the Ministry of Education Department of Biochemistry and Molecular BiologySchool of Basic Medical SciencesCheeloo College of MedicineShandong University Department of Immunology School of Basic Medical SciencesPeking University

Adipogenesis is the healthy expansion of white adipose tissue (WAT),serving as a compensatory response to maintain metabolic homeostasis in the presence of excess energy in the ***,the identification of novel regulatory molecules in adipogenesis,specifically membrane receptors such as G protein-coupled receptors (GPCRs),holds significant clinical *** receptors can serve as viable targets for pharmaceuticals,offering potential for restoring metabolic homeostasis in individuals with *** utilized trajectory inference methods to analyze three distinct single-nucleus sequencing (sNuc-seq) datasets of adipose tissue and systematically identified GPCRs with the potential to regulate *** verification in primary adipose progenitor cells (APCs) of mice,we discovered that ADGRD1 promoted the differentiation of APCs,while GPR39 inhibits this *** the obese mouse model induced by a high-fat diet(HFD),both gain-of-function and loss-of-function studies validated that ADGRD1 promoted adipogenesis,thereby improving metabolic homeostasis,while GPR39 inhibited adipogenesis,leading to metabolic ***,through the analysis of 2,400 ChIP-seq data and 1,204 bulk RNA-seq data,we found that the transcription factors (TFs) MEF2D and TCF12 regulated the expression of ADGRD1and GPR39,*** study revealed the regulatory role of GPCRs in adipogenesis,providing novel targets for clinical intervention of metabolic dysfunction in obese patients.

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Amphiphilic Dendrimer-like Copolymers with High Chain Density by Living Anionic polymerization

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Chinese Journal of polymer Science 2019年第9期37卷 875-883页

作者： Ke Zheng jun-po He State Key Laboratory of Molecular Engineering of polymers Department of Macromolecular Science Fudan University

We report here a method for the preparation of amphiphilic dendrimer-like copolymers with dendritic polystyrene (PS) core and protonated poly(2-vinyl pyridine)(P2VP) or poly(methacrylic acid)(PMAA) shell. The method employed the efficient coupling reaction of anionic living polymer chains and chlorosilane. The synthesis started from a functionalized 3rd generation dendritic polystyrene, G3PS-g-SiCl, used as the precursor. The dendrimer-like copolymer of styrene and 2-vinyl pyridine, G3PS-g-P2VP, was synthesized by direct coupling of living P2VPLi to the precursor. The dendrimer-like copolymer of styrene and Zer/-butyl methacrylate, G3PS-g-PtBMA, was synthesized by an indirect procedure in which a living polymer containing mainly PtBMA segment was attached to the precursor. Both methods resulted in the formation of dendrimer-like copolymers with the high molecular weights (up to 8.5 × 10^6 Da), large molecular sizes (diameter up to 73 nm), and dense shells (number of arms up to 1300). These products, G3PS-g-P2VP and G3PS-g- PtBMA, were protonated with trifluoroacetic acid and acidic hydrolyzed, respectively. After transformation, amphiphilic dendrimer-like copolymers, G3PS-g-P2VPH^+ and G3PS-g-PMAA, were obtained. Preliminary results on the solution properties of the amphiphilic products were presented.

关键词： Dendrimer-like polymer Living anionic polymerization Amphiphilic copolymer

Recent progress in friction stir welding tools used for steels

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Journal of Iron and Steel Research International 2018年第5期25卷 477-486页

作者： Lei Cui Chao Zhang Yong-chang Liu Xiu-guo Liu Dong-po Wang Hui-jun Li Tianjin Key Laboratory of Advanced Joining Technology School of Materials Science and Engineering Tianjin University Tianjin 300354 China State Key Lab of Hydraulic Engineering Simulation andSafety School of Materials Science and Engineering TianjinUniversity Tianjin 300354 China Faculty of Engineering and Information Sciences Universityof Wollongong Wollongong 2522 NSW Australia

Friction stir welding （FSW） technology is being increasingly attractive in welding steels on account of the high-quality weld formation and excellent weld properties. The feasibility of FSW of steels has been convinced for nearly 20 years. However, the application progress for FSW of steels is slower than that of aluminum alloys owing to the high cost and poor usability of tools. The FSW tools are called as the heart of FSW process which is critical for welding quality control and the weld microstructure and properties. The recent progresses in research and development of FSW tools for welding steels have been reviewed. Material selections, geometry parameters, wear behavior and use life of the tools are summarized from the available literatures.

关键词： Friction stir welding Steel FSW process Tool material Tool design Tool wear behavior

On the initiation,movement and deposition of a large landslide in Maoxian County,China

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Journal of Mountain Science 2018年第6期15卷 1319-1330页

作者： pei xiang-jun guo bin cui sheng-hua wang dong-po xu qiang li tian-tao State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology Chengdu 610059 China

At 5 am 24 th june 2017, a catastrophic landslide hit Xinmo Village, Maoxian County, Sichuan Province, China. The slide mass rushed down from an altitude of 3400 m and traveled 2700 m in a high velocity. The 13 million m^3 deposition buried the whole village and caused about 100 deaths. The source area of the landslide is located in a high steep slope, average slope angle is 40o and maximal angle is 65o. The strata are interbedded Triassic Zagunao Formation metamorphic sandstone and slate with the dip slope angle of 45°. Based on high-resolution satellite remote sensing image, UAV image, DEM data, and field investigation, failure mechanism, travel features, and deposit characteristics were analyzed. The results showed that this landslide was influenced by Songpinggou Fault zone. According to the topography before the failure, the landslide is located in the back scarp of an antecedent landslide induced by Diexi Earthquake in 1933. The bedding slope provided potential rupture surface. Historical seismic activities and long-term gravitational deformation caused rock mass accumulated damages. Weathering and precipitation weakened the rock mass and finally induced shearing and tension failure. A huge block detached from the top rock slope, pushed the past landslide deposits in the middle part, rushed out of the slope bottom in a high velocity and buried the Xinmo Village. The rapid movement entrained and brought the soil into the Songping Gully which recoiled with and bounced back from the opposite mountain.

关键词： Xinmo landslide Seismic damages Longrunout Failure mechanism Rock fragment

Numerical Simulation of 4H-SiC Metal Semiconductor Field Transistors

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Chinese Physics Letters 2011年第7期28卷 316-318页

作者： Kuang-po HSUEH Shih-Tzung SU jun ZENG Department of Electronics Engineering Vanung UniversityChung-Li 32061TaiwanChina R&D Department InPowerSemiconductor Corp.LtdHong KongChina

This work simulates the performance of 4H-SiC MESFETs and establishes the optimum device structure for dc and rf applications that operate at high *** with various channel doping,buffer layer doping,recess thickness,gate-to-drain spacing and temperatures of operation are *** simulation results reveal that a p-type buffer layer of 5×10^(15) cm^(−3) and a channel layer of 1×10^(17) cm^(−3 )yield favorable *** cut-off frequency is 22.53 GHz,the maximum transconductance is 50.55 mS/mm,the drain saturation current is 239.76 mA/mm and the breakdown voltage is 70.40 *** breakdown voltages increase to 90.2 V as the gate-to-drain spacing increases to 1µ*** on these simulation results,new 4H-SiC MESFET designs can be calibrated.

关键词： drain breakdown MESFET

Modified Moving Particle Semi-Implicit Meshless Method for Incompressible Fluids

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Journal of Thermal Science 2004年第3期13卷 226-234页

作者： jun guo Zhi Tao Beijing Univ Aeronaut & Astronaut Div 402 Dept Jet Prop Beijing 100083 Peoples R China

A modified moving particle semi-implicit method (MPS) is presented for incompressible fluids. Modification is on the removal of imaginary nodes to enforce the boundary conditions. Comparison with the original imaginary-node scheme has proved the validity of the proposed method. Performance of MPS method in general is also investigated by comparing the results of Lid-driven and natural convection problems with finite volume method (FVM). It is found that MPS method shows relatively strong numerical diffusion, and for convection problems, MPS method appears to be less robust than FVM. Though better results could be obtained with different kernel functions, such improvement is quite limited.

关键词： meshless method incompressible fluids numerical diffusion kernel function.

Statistical Modification Analysis of Helical Planetary Gears based on Response Surface Method and Monte Carlo Simulation

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Chinese Journal of Mechanical Engineering 2015年第6期28卷 1194-1203页

作者： ZHANG jun guo Fan School of Mechanical Engineering Anhui University of Technology

Tooth modification technique is widely used in gear industry to improve the meshing performance of gearings. However, few of the present studies on tooth modification considers the influence of inevitable random errors on gear modification effects. In order to investigate the uncertainties of tooth modification amount variations on system＇s dynamic behaviors of a helical planetary gears, an analytical dynamic model including tooth modification parameters is proposed to carry out a deterministic analysis on the dynamics of a helical planetary gear. The dynamic meshing forces as well as the dynamic transmission errors of the sun-planet 1 gear pair with and without tooth modifications are computed and compared to show the effectiveness of tooth modifications on gear dynamics enhancement. By using response surface method, a fitted regression model for the dynamic transmission error（DTE） fluctuations is established to quantify the relationship between modification amounts and DTE fluctuations. By shifting the inevitable random errors arousing from manufacturing and installing process to tooth modification amount variations, a statistical tooth modification model is developed and a methodology combining Monte Carlo simulation and response surface method is presented for uncertainty analysis of tooth modifications. The uncertainly analysis reveals that the system＇s dynamic behaviors do not obey the normal distribution rule even though the design variables are normally distributed. In addition, a deterministic modification amount will not definitely achieve an optimal result for both static and dynamic transmission error fluctuation reduction simultaneously.

关键词： tooth modification helical planetary gears response surface method Monte Carlo simulation

Geosynthetics used to stabilize vegetated surfaces for environmental sustainability in civil engineering

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Frontiers of Structural and Civil Engineering 2017年第1期11卷 56-65页

作者： Jie HAN jun guo Department of Civil Environmental and Architectural Engineering the University of Kansas Lawrence KS 66044 USA

Geosynthetics, factory-manufactured polymer materials, have been successfully used to solve many geotechnical problems in civil engineering. Two common applications are earth stabilization and erosion control. Geosynthetics used for earth stabilization include but are not limited to stabilized slopes, walls, embankments, and roads. Geosynthetics used for erosion control are mostly related to slopes, river channels and banks, and pond spillways. To enhance environmental sustainability, vegetation has been increasingly planted on the facing or surfaces of these earth structures. Under such a condition, geosynthetics mainly function as surficial soil stabilization while vegetation provides green appearance and erosion protection of earth surfaces. Recently, geosynthetic or geosynthetic-like material has been used to form green walls outside or inside buildings to enhance sustainability. Geosynthetics and vegetation are often integrated to provide combined benefits. The interaction between geosynthetics and vegetation is important for the sustainability of the earth and building wall surfaces. This paper provides a review of the current practice and research in the geosynthetic stabilization of vegetated earth and building surfaces for environmental sustainability in civil engineering with the emphases on geosynthetic used for erosion protection, geosynthetic-stabilized slopes, geosynthetic-stabilized unpaved shoulders and parking lots, and geosynthetic-stabilized vegetated building surfaces.

关键词： erosion geosynthetic stabilization sustainability vegetation

Thoughts and Approaches of Integrated Chinese and Western Medicine for the Treatment of Oligo-astheno-teratozoospermia

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Chinese Journal of Integrative Medicine 2018年第7期24卷 483-486页

作者： guo jun Department of Andrology Xiyuan Hospital China Academy of Chinese Medical Sciences

Oligo-astheno-teratozoospermia（OAT） which perplexes doctors and patients due to its complicated etiology, atypical symptoms and poor clinical efficacy, is a general term for the three pathological states of abnormal semen. OAT is the main factor of male infertility. It is also a hot and difficult point in present studies. Empiric drug is the most popular treatment of this disease in the modern medicine. Chinese medicine（CM） is one of the main methods for the treatment of this disease, and it has certain clinical effect. The author believes that the use of modern medical technology to make the diagnosis as clear as possible is the key to treat OAT. The combination of syndrome and disease differentiation is the main mode in the treatment of OAT. Microscopic syndrome differentiation and macroscopic evidence embodies the basic principle of ＂Si Wai Chuai Nei＂ and broadens the perspective of CM syndrome differentiation. Classification and treatment are basic methods for the treatment of OAT. The treatment should not be limited to the Shen（Kidney）, instead it should focus on the whole body condition. At different stages, the treatment should also pay attention to strengthening the Pi（Spleen）, nourishing the Gan（Liver） and promoting blood circulation. Complementing Chinese and Western medicine, and highlighting the characteristics and advantages of CM treatment, have a great guiding value for the treatment of OAT.

关键词： Oligo-astheno-teratozoospermia integrated Chinese and Western medicine dialectical treatment