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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

Three dimensional discrete element modelling of the conventional compression behavior of gas hydrate bearing coal

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International Journal of Coal Science & Technology 2024年第1期11卷 61-77页

作者： xia Gao Nannan Wang Baoyong Zhang Qiqi Lin Qiang Wu wei meng xia Liu Department of Architecture and Civil Engineering Heilongjiang University of Science and TechnologyHarbin150022China School of Qilu Transportation Shandong UniversityJinan250061China Department of Safety Engineering Heilongjiang University of Science and TechnologyHarbin150022China Jining Hongxiang Highway Survey Design and Research Institute Co.Ltd Jining272000China

To analyze the relationship between macro and meso parameters of the gas hydrate bearing coal(GHBC)and to calibrate the meso-parameters,the numerical tests were conducted to simulate the laboratory triaxial compression tests by PFC3D,with the parallel bond model employed as the particle contact constitutive ***,twenty simulation tests were conducted to quantify the relationship between the macro–meso ***,nine orthogonal simulation tests were performed using four meso-mechanical parameters in a three-level to evaluate the sensitivity of the meso-mechanical ***,the calibration method of the meso-parameters were then ***,the contact force chain,the contact force and the contact number were examined to investigate the saturation effect on the meso-mechanical behavior of *** results show that:(1)The elastic modulus linearly increases with the bonding stiffness ratio and the friction coefficient while exponentially increasing with the normal bonding strength and the bonding radius *** failure strength increases exponentially with the increase of the friction coefficient,the normal bonding strength and the bonding radius coefficient,and remains constant with the increase of bond stiffness ratio;(2)The friction coefficient and the bond radius coefficient are most sensitive to the elastic modulus and the failure strength;(3)The number of the force chains,the contact force,and the bond strength between particles will increase with the increase of the hydrate saturation,which leads to the larger failure strength.

关键词： Gas hydrate bearing coal Discrete element method Triaxial compression test Macro-meso mechanical propertie

Corrugated Graphene Paper Reinforced Silicone Resin Composite for Efficient Interface Thermal Management

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Chinese Journal of Polymer Science 2024年第7期42卷 1002-1014,I0010页

作者： Bo-Wen Wang Heng Zhang Qing-xia He Hui-Tao Yu meng-meng Qin wei Feng Tianjin Key Laboratory of Composite and Functional Materials School of Materials Science and EngineeringTianjin UniversityTianjin300350China International Engineering Institute Tianjin UniversityTianjin300350China

With the rapid development of high-power-density electronic devices,interface thermal resistance has become a critical barrier for effective heat management in high-performance electronic ***,there is an urgent demand for advanced thermal interface materials(TIMs)with high cross-plane thermal conductivity and excellent compressibility to withstand increasingly complex operating *** achieve this aim,a promising strategy involves vertically arranging highly thermoconductive graphene on ***,with the currently available methods,achieving a balance between low interfacial thermal resistance,bidirectional high thermal conductivity,and large-scale production is ***,we prepared a graphene framework with continuous filler structures in in-plane and cross-plane directions by bonding corrugated graphene to planar graphene *** interface interaction between the graphene paper framework and polymer matrix was enhanced via surface functionalization to reduce the interface thermal *** resulting three-dimensional thermal framework endows the polymer composite material with a cross-plane thermal conductivity of 14.4 W·m^(-1)·K^(-1)and in-plane thermal conductivity of 130W·m^(-1)·K^(-1)when the thermal filler loading is 10.1 wt%,with a thermal conductivity enhancement per 1 wt%filler loading of 831%,outperforming various graphene structures as *** its high thermal conductivity,low contact thermal resistance,and low compressive modulus,the developed highly thermoconductive composite material demonstrates superior performance in TIM testing compared with TFLEX-700,an advanced commercial TIM,effectively solving the interfacial heat transfer issues in electronic *** novel filler structure framework also provides a solution for achieving a balance between efficient thermal management and ease of processing.

关键词： Graphene paper Vertically aligned structure Cross-plane thermal conductivity Low compressive modulus Thermal interface material

Continuous-wave operation of 1550 nm low-threshold triple-lattice photonic-crystal surface-emitting lasers

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Light(Science & Applications) 2024年第3期13卷 446-453页

作者： Ziye Wang xia Liu Pinyao Wang Huanyu Lu Bo meng wei Zhang Lijie Wang Yanjing Wang Cunzhu Tong State Key Laboratory of Luminescence and Applications Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Central Research Institute Planning Dept 2012 LabsHuawei Technologies Company Ltd.Shenzhen 518129China

Benefitting from narrow beam divergence,photonic crystal surface-emitting lasers are expected to play an essential role in the ever-growing fields of optical communication and light detection and *** operating with 1.55μm wavelengths have attracted particular attention due to their minimum fiber loss and high eye-safe ***,high interband absorption significantly decreases their performance at this 1.55μm ***,stronger optical feedback is needed to reduce their threshold and thus improve the output *** this goal,photonic-crystal resonators with deep holes and high dielectric contrast are often ***,the relevant techniques for high-contrast photonic crystals inevitably complicate fabrication and reduce the final *** this paper,we demonstrate the first continuous-wave operation of 1.55μm photonic-crystal surface-emitting lasers by using a‘triple-lattice photonic-crystal resonator’,which superimposes three lattice point groups to increase the strength of in-plane optical *** this geometry,the in-plane 180°coupling can be enhanced threefold compared to the normal single-lattice *** theoretical and experimental investigations demonstrate the much lower threshold current density of this structure compared to‘single-lattice’and‘double-lattice’photonic-crystal resonators,verifying our design *** findings provide a new strategy for photonic crystal laser miniaturization,which is crucial for realizing their use in future high-speed applications.

关键词： resonator crystal lattice

The Role of Corticotropin-Releasing Factor Receptor 1 in the Stress-Induced Alteration of Visual Properties in Primary Visual Cortex:Insights from the Single Prolonged Stress Model

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Neuroscience Bulletin 2024年第7期40卷 1012-1016页

作者： Qianhui xia Xi Kuang wei meng Fei Yin Chenchen Ma Yupeng Yang Center for Advanced Interdisciplinary Science and Biomedicine of IHM Division of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230027China

Dear Editor,Stress initiates a cascade of hormonal and behavioral responses that enable an organism to adapt to new environmental *** unbalanced stress response can lead to dysregulation of the hypothalamic-pituitary-... 详细信息

关键词： Corti Receptor Cortex

Development and validation of a prognostic nomogram model for Chinese patients with primary small cell carcinoma of the esophagus

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World Journal of Clinical Cases 2021年第30期9卷 9011-9022页

作者： Dong-Yun Zhang Gai-Rong Huang Jian-wei Ku Xue-Ke Zhao Xin Song Rui-Hua Xu Wen-Li Han Fu-You Zhou Ran Wang meng-xia wei Li-Dong Wang Department of Pathology Nanyang Medical CollegeNanyang 473061Henan ProvinceChina State Key Laboratory of Esophageal Cancer Prevention and Treatment and Henan Key Laboratory for Esophageal Cancer Research of The First Affiliated Hospital Zhengzhou UniversityZhengzhou 450052Henan ProvinceChina Department of Geriatrics Henan People’s HospitalZhengzhou 450003Henan ProvinceChina Department of Endoscopy of The Third Affiliated Hospital Nanyang Medical CollegeNanyang 473061Henan ProvinceChina Department of Thoracic Surgery Anyang Tumor HospitalAnyang 455000Henan ProvinceChina

BACKGROUND Primary small cell carcinoma of the esophagus(PSCE)is a highly invasive malignant tumor with a poor prognosis compared with esophageal squamous cell *** to the limited samples size and the short follow-up time,there are few reports on elucidating the prognosis of PSCE,especially on the establishment and validation of a survival prediction nomogram model covering general information,pathological factors and specific biological proteins of PSCE *** To establish an effective nomogram to predict the overall survival(OS)probability for PSCE patients in *** The nomogram was based on a retrospective study of 256 PSCE *** analysis and multivariate Cox proportional hazards regression analysis were used to examine the prognostic factors associated with PSCE,and establish the model for predicting 1-,3-,and 5-year OS based on the Akaike information *** and validation were assessed by the concordance index(C-index)and calibration curve and decision curve analysis(DCA).Histology type,age,tumor invasion depth,lymph node invasion,detectable metastasis,chromogranin A,and neuronal cell adhesion molecule 56 were integrated into the *** The C-index was prognostically superior to the 7th tumor node metastasis(TNM)staging in the primary cohort[0.659(95%CI:0.607-0.712)vs 0.591(95%CI:0.517-0.666),P=0.033]and in the validation cohort[0.700(95%CI:0.622-0.778)vs 0.605(95%CI:0.490-0.721),P=0.041].Good calibration curves were observed for the prediction probabilities of 1-,3-,and 5-year OS in both *** analysis showed that our nomogram model had a higher overall net benefit compared to the 7th TNM *** Our nomogram can be used to predict the survival probability of PSCE patients,which can help clinicians to make individualized survival predictions.

关键词： Primary small cell carcinoma Decision curve analysis Esophagus Nomogram Prognosis

Unified method for typical gear failure modeling and stiffness calculation based on the matrix equation

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Frontiers of Mechanical Engineering 2024年第3期19卷 93-114页

作者： Fanshan meng Xin ZHANG Heng xia Jiaxu WANG School of Mechanical Engineering Southwest Jiaotong UniversityChengdu 610031China State Key Laboratory of Mechanical Transmissions for Advanced Equipment Chongqing UniversityChongqing 400044China

The failure types in gear systems vary,with typical ones mainly including pitting,cracking,wear,and broken *** modeling and stiffness calculation methods have been developed for various gear failure types.A unified method for typical gear failure modeling and stiffness calculation is introduced in this study by considering the deviations in the time-varying meshing stiffness(TVMS)of faulty gears resulting from the use of different ***,a gear tooth is discretized into a large number of microelements expressed with a matrix,and unified models of typical gear failures are built by adjusting the values of the matrix *** values and positions of the microelements in the tooth failure model matrix have the same physical meaning as the parameter variables in the potential energy method(PEM),so the matrix-based failure model can be perfectly matched with ***,a unified method for TVMS is *** of healthy and faulty gears with pitting,wear,crack,and broken tooth is performed with the matrix equation,and the corresponding TVMS values are calculated by incorporating the matrix models with *** the basis of the results,the mechanism of typical fault types that affect TVMS is analyzed,and the conclusions are verified through the finite element *** developed unified method is a promising technique for studying the dynamic response characteristics of gear systems with different failure types because of its superiority in eliminating stiffness deviations.

关键词： gears matrix equation failure modeling TVMS calculation unified method

Optimizing circumferential assembly angle of rotor parts connected by curvic couplings based on acquired tooth surface error data

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Chinese Journal of Aeronautics 2024年第3期37卷 404-416页

作者： Huibin SUN meng LIU Yingzhi ZHANG Chenle wei Key Laboratory of High Performance Manufacturing for Aero Engine Ministry of Industry and Information TechnologyNorthwestern Polytechnical UniversityXi’an 710072China AECC South Industry Company Limited Zhuzhou 412002China

Due to the excellent self-centering and load-carrying capability,curvic couplings have been widely used in advanced aero-engine ***,curvic tooth surface errors lead to poor assembly *** physical-master-gauge-based indirect tooth surface error measurement and circumferential assembly angle optimization methods have the disadvantages of high cost and weak *** unknown tooth surface fitting mechanism is a big barrier to assembly precision prediction and ***,this work puts forward a data-driven assembly simulation and optimization approach for aero-engine rotors connected by curvic *** origin of curvic tooth surface error is deeply *** 5-axis sweep scan method,a large amount of high-precision curvic tooth surface data are acquired *** on geometric models of parts,the fitting mechanism of curvic couplings is uncovered for assembly precision simulation and prediction.A circumferential assembly angle optimization model is developed to decrease axial and radial assembly *** results show that the assembly precision can be predicted accurately and improved *** uncovering the essential principle of the assembly precision formation and proposing circumferential assembly angle optimization model,this work is meaningful for assembly quality,efficiency and economy improvement of multistage aero-engine rotors connected by curvic couplings.

关键词： Curvic couplings Tooth surface error Assembly precision Axial and radial runouts Circumferential assembly angle

(g,e)-Symmetric Rings

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Algebra Colloquium 2024年第2期31卷 263-270页

作者： Fanyun meng Junchao wei Nanqing Ding School of Mathematics Yangzhou UniversityYangzhouJiangsu 225002China 不详

Let R be a ring and e,g in E(R),the set of idempotents of *** R is called(g,e)-symmetric if abc=0 implies gacbe=0 for any a,b,c∈***,R is an e-symmetric ring if and only if R is a(1,e)-symmetric ring;in particular,R is a symmetric ring if and only if R is a(1,1)-symmetric *** show that e∈E(R)is left semicentral if and only if R is a(1−e,e)-symmetric ring;in particular,R is an Abel ring if and only if R is a(1−e,e)-symmetric ring for each e∈E(R).We also show that R is(g,e)-symmetric if and only if ge∈E(R),geRge is symmetric,and gxye=gxeye=gxgye for any x,y∈*** e-symmetric rings,we construct some new classes of rings.

关键词： idempotent (g,e)-symmetric ring Abel ring left semicentral

A Study on Enhancing Chip Detection Efficiency Using the Lightweight Van-YOLOv8 Network

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Computers, Materials & Continua 2024年第4期79卷 531-547页

作者： meng Huang Honglei wei xianyi Zhai School of Mechanical Engineering and Automation Dalian Polytechnic UniversityDalian116034China

In pursuit of cost-effective manufacturing,enterprises are increasingly adopting the practice of utilizing recycled semiconductor *** ensure consistent chip orientation during packaging,a circular marker on the front side is employed for pin alignment following successful functional ***,recycled chips often exhibit substantial surface wear,and the identification of the relatively small marker proves ***,the complexity of generic target detection algorithms hampers seamless *** these issues,this paper introduces a lightweight YOLOv8s-based network tailored for detecting markings on recycled chips,termed ***,to alleviate the influence of diminutive,low-resolution markings on the precision of deep learning models,we utilize an upscaling approach for enhanced *** technique relies on the Super-Resolution Generative Adversarial Network with Extended Training(SRGANext)network,facilitating the reconstruction of high-fidelity images that align with input ***,we replace the original YOLOv8smodel’s backbone feature extraction network with the lightweight VanillaNetwork(VanillaNet),simplifying the branch structure to reduce network ***,a Hybrid Attention Mechanism(HAM)is implemented to capture essential details from input images,improving feature representation while concurrently expediting model inference *** results demonstrate that the Van-YOLOv8 network outperforms the original YOLOv8s on a recycled chip dataset in various ***,it demonstrates superiority in parameter count,computational intricacy,precision in identifying targets,and speed when compared to certain prevalent algorithms in the current *** proposed approach proves promising for real-time detection of recycled chips in practical factory settings.

关键词： Lightweight neural networks attention mechanisms image super-resolution enhancement feature extraction small object detection