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Chinese Journal of Polymer Science 2024年第7期42卷 916-925,I0006页

作者： Bin Zhang Zheng-li Dou Yong-Zheng Zhang Qiang Fu kai Wu College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu610065China

Effective thermal transport across solid-solid interfaces which is essential in thermal interface materials(TIMs),necessitates both optimal thixotropy and high thermal conductivity.The role of filler surface modification,a fundamental aspect of TIM fabrication,in the influence of these properties is not fully understood.This study employs the use of a silane coupling agent(SCA)to modify alumina,integrating experimental approaches with molecular dynamics simulations,to elucidate the interface effects on thixotropy and thermal conductivity in polydimethylsiloxane(PDMS)-based TIMs.Our findings reveal that the variations of SCAs modify both interface binding energy and transition layer thickness.The interface binding energy restricts macromolecular segmental relaxation near the interface,hindering desirable thixotropy and bond line thickness.On the contrary,the thickness of the transition layer at the interface positively influences thermal conductivity,facilitating the transport of phonons between the polymer and filler.Consequently,selecting an optimal SCA allows a balance between traditionally conflicting goals of high thermal conductivity and minimal bond line thickness,achieving an impressively low interface thermal resistance of just 2.45-4.29 K·mm^(2)·W^(-1)at275.8 kPa.

关键词： Thermal interface material Surface modification Thermal conductivity Thixotropy Interface thermal resistance

Microstructure and damping properties of LPSO phase dominant Mg-Ni-Y and Mg-Zn-Ni-Y alloys

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Journal of Magnesium and Alloys 2024年第3期12卷 1131-1153页

作者： Ruopeng Lu kai Jiao Nanting li Hua Hou Jingfeng Wang Yuhong Zhao College of Materials Science and Engineering North University of ChinaTaiyuan 030051China College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing 400044China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China

This work studied the microstructure,mechanical properties and damping properties of Mg_(95.34)Ni_(2)Y_(2.66) and Mg_(95.34)Zn_(1)Ni_(1)Y_(2.66)alloys systematically.The difference in the evolution of the long-period stacked ordered(LPSO)phase in the two alloys during heat treatment was the focus.The morphology of the as-cast Mg_(95.34)Ni_(2)Y_(2.66)presented a disordered network.After heat treatment at 773 K for 2 hours,the eutectic phase was integrated into the matrix,and the LPSO phase maintained the 18R structure.As Zn partially replaced Ni,the crystal grains became rounded in the cast alloy,and lamellar LPSO phases and more solid solution atoms were contained in the matrix after heat treatment of the Mg_(95.34)Zn_(1)Ni_(1)Y_(2.66)alloy.Both Zn and the heat treatment had a significant effect on damping.Obvious dislocation internal friction peaks and grain boundary internal friction peaks were found after temperature-dependent damping of the Mg_(95.34)Ni_(2)Y_(2.66)and Mg_(95.34)Zn_(1)Ni_(1)Y_(2.66)alloys.After heat treatment,the dislocation peak was significantly increased,especially in the alloy Mg_(95.34)Ni_(2)Y_(2).66.The annealed Mg_(95.34)Ni_(2)Y_(2.66)alloy with a rod-shaped LPSO phase exhibited a good damping performance of 0.14 atε=10^(−3),which was due to the difference between the second phase and solid solution atom content.These factors also affected the dynamic modulus of the alloy.The results of this study will help in further development of high-damping magnesium alloys.

关键词： Mg-Ni-Y alloys Mg-Zn-Ni-Y alloys LPSO phase Heat treatment Microstructure Damping properties.

Effect of tungsten carbide particles on microstructure and mechanical properties of Cu alloy composite bit matrix

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Journal of Iron and Steel Research(International) 2024年第2期31卷 519-530页

作者： Ding-qian Dong Feng-yuan He Xin-hui Chen Hui li kai-hua Shi Hui-wen Xiong Xin Xiang li Zhang College of Mechanical Engineering Sichuan University of Science and EngineeringZigong643000SichuanChina State Key Laboratory of Powder Metallurgy Central South UniversityChangsha410083HunanChina Zigong Cemented Carbide Co. Ltd.Zigong643011SichuanChina Material Corrosion and Protection Key Laboratory of Sichuan Province Sichuan University of Science and EngineeringZigong643000SichuanChina

Copper alloy composite bit matrix was prepared by pressureless vacuum infiltration,using at least one of the three kinds of tungsten carbide particles,for example,irregular cast tungsten carbide,monocrystalline tungsten carbide and sintered reduced tungsten carbide particles.The effects of powder particle morphology,particle size and mass fraction of tungsten carbide on the microstructure and mechanical properties of copper alloy composite were investigated by means of scanning electron microscopy,X-ray diffraction and abrasive wear test in detail.The results show that tungsten carbide morphology and particle size have obvious effects on the mechanical properties of copper alloy composites.Cast tungsten carbide partially dissolved in the copper alloy binding phase,and layers of Cu_(0.3)W_(0.5)Ni_(0.1)Mn_(0.1)C phase with a thickness of around 8–15μm were formed on the edge of the cast tungsten carbide.When 45%irregular crushed fine cast tungsten carbide and 15%monocrystalline cast tungsten carbide were used as the skeleton,satisfactory comprehensive performance of the reinforced copper alloy composite bit matrix was obtained,with the bending strength,impact toughness and hardness reaching 1048 MPa,4.95 J/cm^(2) and 43.6 HRC,respectively.The main wear mechanism was that the tungsten carbide particles firstly protruded from the friction surface after the copper alloy matrix was worn,and then peeled off from the matrix when further wear occurred.

关键词： Polycrystalline diamond compact Pressureless vacuum infiltration Copper alloy composite bit matrix Microstructure characterization Abrasive wear behavior

A Calculation Method of Double Strength Reduction for Layered Slope Based on the Reduction of Water Content Intensity

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工程与科学中的计算机建模(英文) 2024年第1期138卷 221-243页

作者： Feng Shen Yang Zhao Bingyi li kai Wu School of Civil Engineering Suzhou University of Science and TechnologySuzhou215011China R&D Department Suzhou Jcon Greenbuild Fabricated Co.Ltd.Suzhou215004China

The calculation of the factor of safety(FOS)is an important means of slope evaluation.This paper proposed an improved double strength reductionmethod(DRM)to analyze the safety of layered slopes.The physical properties of different soil layers of the slopes are different,so the single coefficient strength reduction method(SRM)is not enough to reflect the actual critical state of the slopes.Considering that the water content of the soil in the natural state is the main factor for the strength of the soil,the attenuation law of shear strength of clayey soil changing with water content is fitted.This paper also establishes the functional relationship between different reduction coefficients.Then,a USDFLD subroutine is programmed using the secondary development function of finite element software.Controlling the relationship between field variables and calculation time realizes double strength reduction applicable to the layered slope.Finally,by comparing the calculation results of different examples,it is proved that the stress and displacement distribution of the critical slope state obtained by the improved method is more realistic,and the calculated safety factor is more reliable.The newly proposedmethod considers the difference of intensity attenuation between different soil layers under natural conditions and avoids the disadvantage of the strength reduction method with uniform parameters,which provides a new idea and method for stability analysis of layered and complex slopes.

关键词： Double strength reduction slopes stability water content factor of safety numerical methods

Emerging role of exosomes in ulcerative colitis: Targeting NOD-like receptor family pyrin domain containing 3 inflammasome

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World Journal of Gastroenterology 2024年第6期30卷 527-541页

作者： Xin li li-Jiang Ji kai-Di Feng Hua Huang Mei-Rou liang Shi-Jin Cheng Xiu-Dong Meng School of Basic Medicine Guizhou University of Traditional Chinese MedicineGuiyang 550025Guizhou ProvinceChina Department of Anorectal Surgery Changshu Hospital Affiliated to Nanjing University of Chinese MedicineChangshu 215500Jiangsu ProvinceChina College of Traditional Chinese Medicine Tianjin University of Traditional Chinese MedicineTianjin 301617China

Ulcerative colitis(UC)is a chronic recurrent inflammatory bowel disease.Despite ongoing advances in our understanding of UC,its pathogenesis is yet unelu-cidated,underscoring the urgent need for novel treatment strategies for patients with UC.Exosomes are nanoscale membrane particles that mediate intercellular communication by carrying various bioactive molecules,such as proteins,RNAs,DNA,and metabolites.The NOD-like receptor family pyrin domain containing 3(NLRP3)inflammasome is a cytosolic tripartite protein complex whose activation induces the maturation and secretion of proinflammatory cytokines interleukin-1β(IL-1β)and IL-18,triggering the inflammatory response to a pathogenic agent or injury.Growing evidence suggests that exosomes are new modulators of the NLRP3 inflammasome,with vital roles in the pathological process of UC.Here,recent evidence is reviewed on the role of exosomes and NLRP3 inflammasome in UC.First,the dual role of exosomes on NLRP3 inflammasome and the effect of NLRP3 inflammasome on exosome secretion are summarized.Finally,an outlook on the directions of exosome-NLRP3 inflammasome crosstalk research in the context of UC is proposed and areas of further research on this topic are high-lighted.

关键词： Ulcerative colitis Exosomes Inflammasome Evidence Therapeutics

Artificial stepwise light harvesting system in water constructed by quadruple hydrogen bonding supramolecular polymeric nanoparticles

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Chinese Chemical Letters 2024年第2期35卷 370-373页

作者： Tangxin Xiao Xiuxiu li liangliang Zhang kai Diao Zheng-Yi li Xiao-Qiang Sun Leyong Wang Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology School of Petrochemical EngineeringChangzhou UniversityChangzhou 213164China Jiangsu Key Laboratory of Advanced Organic Materials School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

Stepwise energy transfer is ubiquitous in natural photosynthesis,which greatly promotes the widespread use of solar energy.Herein,we constructed a supramolecular light harvesting system based on sequential energy transfer through the hierarchical self-assembly of M,which contains a cyanostilbene core flanked by two ureidopyrimidinone motifs,endowing itself with both aggregation-induced emission behavior and quadruple hydrogen bonding ability.The monomer M can self-assemble into hydrogen bonded polymers and then form supramolecular polymeric nanoparticles in water through a mini-emulsion process.The nanoparticles were further utilized to encapsulate the relay acceptor ESY and the final acceptor NDI to form a two-step FRET system.Tunable fluorescence including a white-light emission was successfully achieved.Our work not only shows a desirable way for the fabrication of efficient two-step light harvesting systems,but also shows great potential in tunable photoluminescent nanomaterials.

关键词： light harvesting system Supramolecular polymer Quadruple hydrogen bonding AIE Self-assembly

High-resolution multi-scale air pollution system:Evaluation of modelling performance and emission control strategies

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Journal of Environmental Sciences 2024年第3期137卷 65-81页

作者： Diogo Lopes Joana Ferreira Sandra Rafael Ka In Hoi Xin li Yuan liu Ka-Veng Yuen kai Meng Mok Ana Isabel Miranda Department of Environment and Planning&CESAM University of AveiroAveiroPortugal Department of Civil&Environmental Engineering Faculty of Science and TechnologyUniversity of MacaoMacao SARChina

A high percentage of the world's population lives in areas where air pollutant concentrations exceed the World Health Organization guidelines.This work aims to develop and test,a high-resolution multi-scale air pollution modelling system by integrating a set of adequate tools.This system is able to provide detailed air pollutant concentrations in urban areas and support air quality management strategies through a better identification of different atmospheric processes.It also allows furthering the design and assessment of air pollution control measures for a specific area.To evaluate its performance and suitability,the system was applied to the Macao Special Administrative Region(SAR),China,one of the most densely populated areas on earth,during a winter period when this area is affected by high levels of Particulate Matter(PM).Although the developed system tends to underestimate the PM concentrations,it revealed a good performance in reproducing the temporal and spatial air pollution patterns.Several exceedances of the Chinese air quality standards were calculated and high population exposure to PM pollution was estimated.The tested urban atmospheric emission reduction scenarios have shown air quality improvements,indicating that emission reduction measures at urban level should focus on the domestic sector.However,it is crucial to implement joint pollution prevention strategies with neighbouring regions to improve the air quality in Macao SAR.The approach developed in this work can support policymakers in defining new strategies to reduce atmospheric pollution in urban areas.

关键词： Urban areas High-resolution emission inventory Particulate matter Population exposure

Automatic velocity picking based on optimal key points tracking algorithm

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Petroleum Science 2024年第2期21卷 903-917页

作者： Yong-Hao Wang Wen-kai Lu Song-Bai Jin Yang li Yu-Xuan li Xiao-Feng Gu The Institute for Artificial Intelligence(THUAI) Tsinghua UniversityBeijing100084China State Key Laboratory of Intelligent Technology and Systems Tsinghua UniversityBeijing100084China Beijing National Research Center for Information Science and Technology(BNRist) Beijing100084China The Department of Automation Tsinghua UniversityBeijing100084China

Picking velocities from semblances manually is laborious and necessitates experience. Although various methods for automatic velocity picking have been developed, there remains a challenge in efficiently incorporating information from nearby gathers to ensure picked velocity aligns with seismic horizons while also improving picking accuracy. The conventional method of velocity picking from a semblance volume is computationally demanding, highlighting a need for a more efficient strategy. In this study, we introduce a novel method for automatic velocity picking based on multi-object tracking. This dynamic tracking process across different semblance panels can integrate information from nearby gathers effectively while maintaining computational efficiency. First, we employ accelerated density clustering on the velocity spectrum to discern cluster centers without the requirement for prior knowledge regarding the number of clusters. These cluster centers embody the maximum likelihood velocities of the main subsurface structures. Second, our proposed method tracks key points within the semblance volume. Kalman filter is adopted to adjust the tracking process, followed by interpolation on these tracked points to construct the final velocity model. Our synthetic data example demonstrates that our proposed algorithm can effectively rectify the picking errors of the clustering algorithm. We further compare the performances of the clustering method(CM), the proposed tracking method(TM), and the variational method(VM) on a field dataset from the Gulf of Mexico. The results attest that our method offers superior accuracy than CM, achieves comparable accuracy with VM, and benefits from a reduced computational cost.

关键词： Velocity picking Multi-object tracking Density clustering Kalman filter

Rheum palmatum L. and Salvia miltiorrhiza Bge. Alleviates Acute Pancreatitis by Regulating Th17 Cell Differentiation: An Integrated Network Pharmacology Analysis, Molecular Dynamics Simulation and Experimental Validation

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Chinese Journal of Integrative Medicine 2024年第5期30卷 408-420页

作者： FENG Min-chao LUO Fang HUANG liang-jiang li kai CHEN Zu-min li Hui YAO Chun QIN Bai-jun CHEN Guo-zhong The First Clinical Medical College Guangxi University of Traditional Chinese MedicineNanning 530000China Guangxi Key Laboratory of Molecular Biology of Traditional Chinese Medicine and Preventive Medicine Nanning 530000China Graduate School Guangxi University of Traditional Chinese MedicineNanning 530000China Department of Gastroenterology the First Affiliated Hospital of Guangxi University of Traditional Chinese MedicineNanning 530023China

Objective: To identify the core targets of Rheum palmatum L. and Salvia miltiorrhiza Bge.,(Dahuang-Danshen, DH-DS) and the mechanism underlying its therapeutic efficacy in acute pancreatitis(AP)using a network pharmacology approach and validate the findings in animal experiments. Methods: Network pharmacology analysis was used to elucidate the mechanisms underlying the therapeutic effects of DH-DS in AP. The reliability of the results was verified by molecular docking simulation and molecular dynamics simulation.Finally, the results of network pharmacology enrichment analysis were verified by immunohistochemistry,Western blot analysis and real-time quantitative PCR, respectively. Results: Sixty-seven common targets of DH-DS in AP were identified and mitogen-activated protein kinase 3(MAPK3), Janus kinase 2(JAK2), signal transducer and activator of transcription 3(STAT3), protein c-Fos(FOS) were identified as core targets in the protein interaction(PPI) network analysis. Gene ontology analysis showed that cellular response to organic substance was the main functions of DH-DS in AP, and Kyoto Encyclopedia of Genes and Genomes analysis showed that the main pathway included Th17 cell differentiation. Molecular docking simulation confirmed that DH-DS binds with strong affinity to MAPK3, STAT3 and FOS. Molecular dynamics simulation revealed that FOS-isotanshinone Ⅱ and STAT3-dan-shexinkum d had good binding capacity. Animal experiments indicated that compared with the AP model group, DH-DS treatment effectively alleviated AP by inhibiting the expression of interleukin-1β, interleukin-6 and tumor necrosis factor-α, and blocking the activation of Th17 cell differentiation(P<0.01). Conclusion: DH-DS could inhibit the expression of inflammatory factors and protect pancreatic tissues,which would be functioned by regulating Th17 cell differentiation-related m RNA and protein expressions.

关键词： Rheum palmatum L. Salvia miltiorrhiza Bge. molecular docking simulation network pharmacology acute pancreatitis Th17 cell differentiation

Neuroprotective and anti-inflammatory effects of eicosane on glutamate and NMDA-induced retinal ganglion cell injury

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International Journal of Ophthalmology(English edition) 2024年第4期17卷 638-645页

作者： Zhen-kai Wu Huan-Yu li You-lin Zhu Meng-Qin Xiong Jing-Xiang Zhong Department of Ophthalmology the First Affiliated Hospital of Jinan UniversityGuangzhou 510632Guangdong ProvinceChina Changde Hospital Xiangya School of MedicineCentral South University(the First People’s Hospital of Changde City)Changde 415000Hunan ProvinceChina

AIM:To investigate the protective effects,antioxidant potential,and anti-inflammatory mechanisms of eicosane on glutamate-induced cell damage and on N-methyl-Daspartate(NMDA)-induced retinal ganglion cell(RGC)injury in a mouse model of glaucoma.METHODS:The protective effects of eicosane on the rat R28 retinal precursor cell line were assessed using cell counting kit-8 assays and Hoechst-propidium iodide staining.Intracellular reactive oxygen species(ROS)production was measured using the fluorescent probe 2'-7'-dichlorofluorescin diacetate and flow cytometry.The protective role of eicosane on NMDA-induced RGC injury in a mouse glaucoma model was determined by immunostaining of frozen sections of retina.The effects of eicosane on the metabolome of the retina in mice with NMDA-induced RGC damage were evaluated by liquid chromatographymass spectroscopy(LC-MS)and untargeted metabolomics analyses.RESULTS:Eicosane treatment significantly attenuated glutamate-induced damage to R28 cells in vitro.Eicosane also protected RGCs against NMDA-induced injury in a mouse glaucoma model.Untargeted metabolomics analyses showed that eicosane increased multiple metabolites,including L-arginine and L-carnitine,in the retina.CONCLUSION:Eicosane has protective effects,antioxidant potential,and anti-inflammatory properties in an in vitro model of glutamate-induced cell damage and in an in vivo model of NMDA-induced RGC injury in mouse glaucoma through modulation of L-arginine and/or L-carnitine metabolism.

关键词： glaucoma metabolites eicosane