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structural parameters of CVD synthesized Ga2O3 nanostructures from X-ray diffraction analysis derived by Scherrer, Williamson-Hall, Size-Strain Plot and Halder-Wagner methods-A comparative study

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PHYSICA B-CONDENSED MATTER 2025年 699卷

作者： Lim, Jieh Sim Yam, Fong Kwong Univ Sains Malaysia USM Sch Phys George Town 11800 Malaysia

Gallium oxide (Ga2O3) nanostructures (NSs) have been synthesized by hydrogen-reducing chemical vapor deposition method at various substrate angles. X-ray diffraction (XRD) study confirms the polycrystalline nature of the Ga2O3 NSs with monoclinic structure. Here, a series of X-ray peak profile analysis models such as Scherrer method, Monshi-Scherrer (M- S) plot, Williamson-Hall (W-H) plot, Size-Strain plot (S-S-P) and Halder-Wagner (H-W) technique have been utilized to estimate the crystallite size and lattice strain. All the models are evaluated with their merits and demerits in detail, and the structural parameters determined from different models are compared. Among the X-ray peak profile analysis methods, S-S-P method is the most suitable since the data points more accurately fit in this method with the highest average goodness of fit, R 2 value. It has also been suggested that the anisotropic strain could have increased and shifted to lower angles crystallographic reflections as the substrate angle was >= 67.5 degrees .

关键词： X-ray diffraction structural parameters Williamson-Hall Size-Strain Plot Halder-Wagner models

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structural parameters of Mechanically Alloyed Cementite Doped with Nickel and Chromium

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RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY A 2025年第4期99卷 904-914页

作者： Dobysheva, L. V. Russian Acad Sci Udmurt Fed Res Ctr Ural Branch Izhevsk 426067 Russia

The changes in the structural parameters of phases in the mechanically alloyed (Fe100-x-yCrxNiy)(75)C-25 system are considered depending on the annealing temperature and the concentrations of chromium and nickel. The XRD data obtained previously are considered for different samples, and it is shown that the lattice parameters of the cementite phase should be compared for the samples obtained under the best synthesis conditions. The lattice parameters of the phases formed after mechanical alloying differ from the reference values, approaching them at increased annealing temperatures. The lattice parameters of cementite formed after annealing also change depending on the doping element and differ from the parameters of both the reference cementite and the undoped mechanically alloyed cementite, which is explained by the influence of chromium and nickel on the lattice.

关键词： mechanical alloying cementite doping structural parameters

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Dynamic Analysis of Vertical Magnetic Suspension System Rotor Dropping to Protective Bearing with Different structural parameters

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INTERNATIONAL JOURNAL OF PRECISION ENGINEERING AND MANUFACTURING 2025年第1期26卷 133-155页

作者： Zhu, Dingkang Pang, Xiaoxu Wang, Dongfeng Qiu, Ming Liu, Duo Dong, Yanfang Xu, Bobo Henan Univ Sci & Technol Sch Mech & Elect Engn Luoyang 471003 Peoples R China Luoyang Bearing Sci & Technol Co Ltd Luoyang 471003 Peoples R China Luoyang Assoc Bearing Ind Luoyang 471003 Peoples R China

Aiming at the problem that the rotor of vertical magnetic suspension system falls to the protective bearing with different structural parameters and causes its failure, in this paper, the dynamic model of the inner structure of the protective bearing, the mathematical model of axial and radial collision between the rotor, the inner ring of the protective bearing are established. The author changed the two structural parameters of protective bearing with and without cage and the ball filling number, and the impact characteristics of WNCPB (with no cage protective bearing) and WCPB (with cage protective bearing) on the rotor were compared and analyzed. Finally, the protective bearing performance testing machine of the magnetic bearing system was built to simulate and calculate the impact force of the outer ring, and the indirect measurement experiment of the axial and radial impact force of the protective bearing with different structural parameters was carried out. The empirical results show that: the impact resistance of WCPB improved with the ball filling number increasing from 26 to 28. The number of WNCPB filled balls should be slightly less than the number of full balls to obtain optimal impact resistance. With the ball filling number increasing from 26 to 28 and then to 30, WNCPB with the ball filling number 28 has the best impact resistance. Compared to WNCPB, the overall performance of WCPB is improved.

关键词： Vertical magnetic suspension system Protective bearing structural parameters Collision characteristics

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Numerical study on cavity-vortex evolution in cavitation flow in nuclear control valves with different openings and structural parameters

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ANNALS OF NUCLEAR ENERGY 2025年 211卷

作者： Xu, Xiaogang Wang, Yong Fang, Liang Wang, Zhenbo Li, Yongtong Lanzhou Univ Technol Coll Petrochem Technol Lanzhou 730050 Peoples R China China Univ Petr East China Coll New Energy Qingdao 266580 Peoples R China Wei Fang Univ Inst Low Carbon Technol Weifang 261000 Peoples R China

Nuclear control valves operating under high pressure drop often experience damage such as cavitation, vibration, and noise, which pose a significant safety risk to the nuclear plant. However, there is currently a lack of research on the unsteady cavity-vortex evolution, resulting in a limited understanding of cavitation flow in valves. In this study, the evolution of the cavity-vortex structures in control valves with different openings and structural parameters was studied, and the unsteady characteristics of flow were analysed by mechanical energy pulsation. Results indicate that, under the same pressure ratio conditions, reducing valve opening increases the influence range of quasi-periodic cavity-vortex structures and cavitation intensity. Furthermore, the unsteady pulsation of flow parameters becomes more obvious. Additionally, increasing the throat length-to-diameter ratios or decreasing the expansion angle enhances the evolution of cavity-vortex, which consequently has a stronger impact on flow unsteadiness. Therefore, it is recommended to avoid small openings and maximize the effective flow area of the throttling passage within the allowable range.

关键词： Control valve Cavity Vortex structural parameters LES

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Stress Measurement and Analysis of structural parameters of Flat Arm Tower Crane Under Different Working Conditions

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BUILDINGS 2025年第7期15卷 1137-1137页

作者： Zhang, Qinghua Mei, Bohao Yang, Hui Hu, Xin An, Wei Yue, Yanpeng Xu, Yanwei Wang, Zhihao North China Univ Water Resources & Elect Power Sch Civil Engn & Commun Zhengzhou 450045 Peoples R China China Construct Third Engn Bur Grp Co Ltd Wuhan 430064 Peoples R China State Grid Henan Econ Res Inst Zhengzhou 450000 Peoples R China Power China Henan Elect Power Engn Co Ltd Zhengzhou 450007 Peoples R China

With the expansion of high-rise building construction in China, tower cranes have become indispensable key equipment in the construction industry. To ensure the safety and structural reliability of tower cranes under complex working conditions, this paper takes a typical 40 m-high flat-arm tower crane as the research object. For the first time, the orthogonal test method was used to monitor the stress of key components (the root of the tower body and the root of the boom). The stress distribution characteristics of the tower crane structure under different working conditions were systematically analyzed. Then, based on the power spectral density analysis method, the natural frequency of the tower crane structure was identified. The influence of key structural parameters, such as lifting position, rope length, and lifting weight, on the stress of the tower crane was quantitatively studied through orthogonal experiments, revealing the multi-parameter coupling effect. The results show that the stress at the measuring point at the root of the tower body is significantly higher than that at the root of the boom. This indicates that the root of the tower body is the primary stress-bearing part of the tower crane structure, highlighting the need to focus on its fatigue performance and safety assessment. Based on the power spectral density analysis of the root stress of the tower crane, the natural frequencies of the tower crane structure were accurately identified. The first-order frequency was 0.10 Hz, and the second-order frequency was 0.20 Hz, providing data support for the study of the tower crane's dynamic characteristics. The orthogonal test analysis shows that the influences of lifting position, rope length, and lifting weight on the stress of the tower crane are consistent, with no significant differences. The effects of lifting position and rope length on stress are dominant, while the influence of lifting weight is relatively small. These research findings provid

关键词： flat arm tower crane stress measurement structural parameters orthogonal experiment

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Influence of structural parameters on the performance of fluid oscillators

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EUROPEAN JOURNAL OF MECHANICS B-FLUIDS 2025年 109卷 367-377页

作者： Zhai, Wenhui Fan, Yuxin Nanjing Univ Aeronaut & Astronaut Coll Energy & Power Engn Nanjing 210016 Peoples R China Inner Mongolia Univ Technol Coll Aviat Hohhot 010051 Peoples R China

The fluid oscillator, relying on the Coanda effect, is a flow control device that can alter the direction or velocity of a jet both spatially and temporally. The fuel injection device based on a fluid oscillator significantly enhances atomization and spatial dispersion performance compared to a direct-spray nozzle. However, when used in high heat load afterburners with aviation kerosene as the working medium, oxidative coking issues may arise. To address this, it is recommended to use premixed rich fuel-vapor as the working fluid in order to reduce the residence time of fuel in the oscillator. This study investigates the flow rate and frequency variation of ideal air (simulated gas phase fuel) as it moves through a double feedback channel fluid oscillator with varying thicknesses and outlet throat widths. Experimental and numerical simulation methods are employed. And the influence mechanism is analyzed through an examination of the flow field structure within the cavity of the fluid oscillator. The results indicate that increasing the thickness of the fluid oscillator leads to a higher outlet tangential velocity and deflection angle, while simultaneously decreasing the oscillation frequency. Conversely, widening the fluid oscillator throat results in a decrease in tangential velocity, deflection angle, and oscillation frequency. The performance of the fluid oscillator reaches a critical threshold when the outlet throat is square. As thickness increases, the rate of decrease in oscillation frequency and the rate of increase in tangential velocity both slow down. Furthermore, the maximum deflection angle of the airflow at the oscillator outlet reaches a critical value at a thickness of 3.375 mm, beyond which the trend of increasing deflection angle also slows. When the thickness of the oscillator is less than 3.375 mm, mass flow is the predominant driving factor for airflow deflection in the mixing chamber. In contrast, when the thickness is greater than or equal to

关键词： Fluid oscillator structural parameters Flow characteristics Oscillation characteristics CFD Hot-wire anemometer

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Numerical study of structural parameters on the performance of piccolo-tube muti-nozzles supersonic ejector in air-cooled passage

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CASE STUDIES IN THERMAL ENGINEERING 2025年 69卷

作者： Yang, Zhen-Xi Zhang, Jing-Yang Cheng, Feng-Na Chen, Li-Jun Geng, Jin-Xin Gong, Zheng-Xi Nanjing Univ Aeronaut & Astronaut Coll Astronaut Nanjing 210016 Peoples R China Nanjing Forestry Univ Coll Mech & Elect Engn Nanjing 210037 Peoples R China Aviat Key Lab Sci & Technol Aero Electromech Syst Nanjing Peoples R China

The enhanced performance of aircraft engines has intensified the challenge of improving cooling efficiency. In addressing the issue of inadequate cooling air in the idle and taking-off states, which adversely affects the working environment of the radiator within the air-cooled channel of aircraft engines, an enhanced cooling design method utilizing a piccolo-tube multi-nozzle supersonic ejector is investigated in this study. The structural parameters-including the number of nozzles, the arrangement of multiple nozzles, and the cross-sectional shape of the mixing chamber-are optimized to enhance entrainment performance. Changes to the structure of the ejector can impact its entrainment performance by altering the flow field. The findings indicate that when maintaining a constant total area for the nozzle throat, the entrainment performance of a double-row piccolo-tube ejector (DPE) surpasses that of a single-row piccolo-tube ejector (SPE), with an increase in entrainment ratio ranging from 16 % to 20 %. There exists an optimal number of nozzles that yield superior entrainment performance. Specifically, compared to the original SPE configuration featuring six nozzles, the optimized DPE demonstrates a 29 % improvement in entrainment ratio under identical conditions. In addition, it is observed that variations in mixing chamber cross-section shape significantly impact entrainment performance by influencing vortex behavior near the wall.

关键词： Muti-nozzles ejector Numerical simulation structural parameters Entrainment performance Porous medium

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Effect of structural parameters on the Auxetic Behavior of Weft-Knitted Fabrics Based on Foldable Structures

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FIBERS AND POLYMERS 2025年第1期26卷 391-401页

作者： Aghazadeh, Shiva Nosraty, Hooshang Asayesh, Azita Rabiee, Mohammad Amirkabir Univ Technol Dept Text Engn Tehran Polytech Tehran Iran Amirkabir Univ Technol Tehran Polytech Dept Biomed Engn Tehran Iran

Auxetic materials refer to materials with a negative Poisson's ratio (NPR). They expand when stretched and become slimmer when compressed. Due to the special features of auxetic materials, they are used in a wide range of industrial applications including medical, fashion and clothing, composite, sports, and protective applications. This study aims to design and develop auxetic weft-knitted fabrics based on a horizontal zigzag structure with different structural patterns and investigate the influence of various parameters on their auxetic behavior. Auxetic fabrics with three patterns and three loop lengths were knitted using polyester yarn with different counts. Subsequently, the auxetic behavior of each fabric sample was examined. The results denote that the negative Poisson's ratio decreases with increasing strain. The effect of the fabric knit pattern with different angles on the auxetic behavior is different in the course and wale directions. Fabrics with higher loop lengths have a higher initial negative Poisson's ratio (NPR), while fabrics with smaller loop lengths exhibit auxetic behavior in a wider strain range. Furthermore, optimizing the fabric structure and dimensional parameters such as yarn count and loop length can enhance auxetic behavior. This research provides a useful study for optimizing auxetic fabric properties by changing structural parameters and developing innovative applications for materials with special mechanical properties.

关键词： Weft-knitted fabrics Auxetic Negative Poisson's ratio (NPR) structural parameters

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A unified stiffness model of rolling lobe air spring with nonlinear structural parameters and air pressure dependence of rubber bellows

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PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART D-JOURNAL OF AUTOMOBILE ENGINEERING 2025年第2-3期239卷 407-431页

作者： Chen, Jun-Jie Huang, Zi-Qi Liu, Hong-Jiang Qiu, Guang-Qi Gu, Ying-Kui Jiangxi Univ Sci & Technol Sch Mech & Elect Engn Sch Automot Engn Ganzhou Peoples R China Yanshan Univ Hebei Key Lab Special Delivery Equipment Qinhuangdao Hebei Peoples R China KH Automot Technol Co Ltd Huzhou Zhejiang Peoples R China Jiangxi Univ Sci & Technol Sch Mech & Elect Engn Sch Automot Engn Ganzhou 341000 Peoples R China

The structural parameters of the rolling lobe air spring and the mechanical characteristic of rubber bellows are the key factors affecting the stiffness and mechanical characteristic of the rolling lobe air spring. Aiming at the prediction difficulties of structural parameters of the rolling lobe air spring with the composite curved contour piston and the modeling complexity of the hysteretic mechanical characteristic of rubber bellows under variable pressure conditions, the geometrical method is applied to derive the structural parameters models of the rolling lobe air spring with the composite curved contour piston. A new pressure factor is introduced and the Coulomb frictional pressure perturbation model and the fractional derivative Kelvin-Voigt pressure perturbation model are reconstructed to accurately describe the hysteretic mechanical characteristic of rubber bellows under variable pressure conditions. A unified pressure equation is constructed to characterize the evolution of model parameters under variable pressure conditions. Furthermore, a hysteretic mechanical characteristic pressure perturbation model (abbreviated as HMCPP model) of rubber bellows under variable pressure conditions is put forward. Finally, a unified stiffness model of the rolling lobe air spring including prediction models of nonlinear structural parameters and a HMCPP model of rubber bellows is built. Taking a certain type of rolling lobe air spring as the test sample A, the structural parameters tests and static/dynamic characteristic tests of sample A are carried out based on the MTS852.05 test bench, which verified the accuracy of the unified stiffness model of the rolling lobe air spring. The research results provide theoretical support for the mechanical characteristic matching and air pressure precise control of the rolling lobe air spring under variable pressure conditions.

关键词： Rolling lobe air spring structural parameters rubber bellows hysteretic mechanical characteristic pressure

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Mechanical behavior of reinforced Al2O3 lattice structures: Effects of structural parameters from experiments and simulations

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THIN-WALLED STRUCTURES 2025年 207卷

作者： Zhong, Ke Wang, Zhiguo Cui, Jin Yu, Xuehua Zhang, Mingtao He, Zhenfeng Zhao, Yuhui Zhao, Jibin Chinese Acad Sci Shenyang Inst Automat State Key Lab Robot Shenyang 110016 Liaoning Peoples R China Univ Chinese Acad Sci Beijing 100049 Peoples R China Guangxi Univ Sch Mech Engn Inst Laser Intelligent Mfg & Precis Proc Nanning 530004 Peoples R China

The pressure hull is one of the core components of autonomous underwater vehicles (AUVs), necessitating a new structural material with improved mechanical and lightweight properties. For this purpose, a novel type of reinforced lattice structure (RLS) that integrates Al2O3 lattice structures (ALSs) with phenol-formaldehyde (PF) resin was designed and fabricated via stereolithography (SL)-based additive manufacturing and infiltration processes. The responses of the RLSs with different structural configurations, relative densities, and unit cell sizes under compressive loading were systematically characterized. Additionally, numerical simulations were conducted to further predict and study the mechanical behavior of the RLSs using Johnson-Holmquist-II (JH-2) model. The results revealed that the mechanical properties of the RLSs from superior to inferior were simple cubic (SC), body-centered cubic (BCC), Gyroid, octet truss (Oct), and SchwarzP (Sch). As the relative density and the unit cell size increased, the mechanical properties of the RLSs increased. Furthermore, the results of the numerical simulations closely aligned with the experimental results, which provided an in-depth analysis of internal damage and crack propagation in the RLSs under compression. A comparison of the mechanical properties also demonstrated that RLSs exhibit superior compressive strength and energy absorption performance than traditional ALSs do. After this investigation, this type of RLS is anticipated to facilitate lightweighting of AUVs, advancing the development of deep-sea scientific research.

关键词： Ceramic/resin composite structure structural parameters Additive manufacturing Mechanical properties Numerical simulation

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