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Measurement of two-phase velocities in bubble flows using laser Doppler velocimetry

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Journal of Hydrodynamics 2022年第6期34卷 1134-1144页

作者： Ling-xin Zhang Xin-sheng Cheng Han Tu Qi Gao Xue-ming Shao xiang-wei liao Liang Zhao Department of Engineering Mechanics Zhejiang UniversityHangzhou310027China Iron and Steel Research Institutes of Ansteel Group Corporation Anshan114009China State Key Laboratory of Metal Material for Marine Equipment and Application Anshan114009China

The measurement of two-phase velocities in bubble flows using laser Doppler velocimetry(LDV)is *** key to the problem is to differentiate the LDV signals from bubbles and tracers,based on which the two-phase velocities can be *** this study,two experiments are carried ***,the bubble-chain experiment is performed to investigate the optical response of bubble surface and the corresponding LDV *** optical response shows that the light received by the LDV detector is dominated by the reflection component,which is similar to specular reflection to some *** are three typical patterns of signals of large bubbles passing through the measurement volume,all of which are with high amplitude and ***,the upward-flow experiment is conducted to study the statistical characteristics of large bubbles as well as micro tracers and micro *** results show that the amplitude of signal of millimeter bubbles is about an order of magnitude larger than that of tracers or micro *** on this significant difference of the amplitude,we propose a phase discrimination method to distinguish two-phase *** capability of the proposed method is tested in a complex bubble flow,and its reliability is verified by bubble tracking velocimetry(BTV)technology.

关键词： laser Doppler velocimetry(LDV) bubbly flow phase discrimination bubble tracking velocimetry(BTV)

Effect of hollow insulation riser on shrinkage porosity and solidification structure of ingot

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Journal of Iron and Steel Research International 2022年第12期29卷 1951-1960页

作者： Ying-jie Liu Chun-lin Peng Wan-ming Li Xiao-lei Zhu Ming-gang Shen xiang-wei liao Kun Liu Chong-yi wei Yusuf Abba Yusuf Ji Yang Chang-you Cai School of Materials and Metallurgy University of Science and Technology LiaoningAnshan 114051LiaoningChina State Key Laboratory of Metal Material for Marine Equipment and Application Anshan 114000LiaoningChina

The thermal insulation performance of riser is very important to the shrinkage porosity and solidification structure of ingot,but it is difficult to significantly improve due to the limit of thermal conductivity of riser material.A new type of hollow insulation riser was proposed based on the low thermal conductivity of air,which aims to improve the thermal insulation performance of riser.A 14.5-t steel ingot was prepared using the hollow insulation riser,and the casting temperature was 1500°*** temperature evolution of the external surface of mold during solidification was measured using an infrared temperature instrument.A numerical model was established to simulate the porosity and solidification structure of *** reliability of numerical simulation was verified by comparing simulation and experimental *** show that the insulation performance of the riser can be significantly improved through application of the hollow insulation *** with solid insulation sleeve,the shrinkage cavity depth was decreased and the position of porosity was raised when hollow insulation riser was applied.

关键词： Hollow insulation riser Solidification Heat transfer Porosity Thermal conductivity

A six-variable quasi-3D isogeometric approach for free vibration of functionally graded graphene origami-enabled auxetic metamaterial plates submerged in a fluid medium

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 157-176页

作者： wei CHEN Zhihong TANG Yufen liao Linxin PENG College of Civil Engineering University of South China College of Civil Engineering and Architecture Guangxi University Key Laboratory of Disaster Prevention and Structural Safety of Ministry of Education Guangxi University

This paper presents, for the first time, an effective numerical approach based on the isogeometric analysis(IGA) and the six-variable quasi-three dimensional(3D)higher-order shear deformation theory(HSDT) to study the free vibration characteristics of functionally-graded(FG) graphene origami(GOri)-enabled auxetic metamaterial(GOEAM) plates submerged in a fluid medium. The plate theory incorporates the thickness stretching and the effects of transverse shear deformation without using any shear correction factors. The velocity potential function and Bernoulli's equation are used to derive the hydrodynamic pressure acting on the plate surface. Both horizontally and vertically immersed plate configurations are considered here in the form of inertia *** plates are composed of multilayer GOEAMs, with the GOri content varying through the plate's thickness in a layer-wise manner. This design results in graded auxetic *** material properties are evaluated by mixing rules and a genetic programming(GP)-assisted micromechanical model. The governing equations of motion for the FG-GOEAM plates immersed in a fluid medium are derived by Hamilton's principle. After validating the convergence and accuracy of the present model, a comprehensive parametric study is carried out to examine the effects of the GOri content, GOri distribution pattern, GOri folding degree, fluid level, immersed depth, and geometric parameter on the natural frequencies of the FG-GOEAM plates. The results show that the natural frequencies for the four GOri distribution patterns increase with the increase in the layer number when the lay number is fewer than 10, and then stabilize after the layer number reaches ***, in general, the natural frequency of the FG-GOEAM plate in a vacuum or fluid increases when the GOri content increases, while decreases when the GOri folding degree increases. Some additional findings related to the numerical results are presented in the conclusions. It is belie

关键词： Equations of motion

Fatigue Strength Analysis of Dissimilar Aluminum Alloy TIG Welds

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 265-274页

作者： liao xiangyun WANG Ruijie LIU Guoshou ZHAO Pinglin Faculty of Mechanical and Electrical Engineering Kunming University of Science and TechnologyKunming 650500China Faculty of Civil Engineering and Mechanics Kunming University of Science and TechnologyKunming 650500China

The constant amplitude loading fatigue tests were carried out on the 6061/7075 aluminum alloy TIG fillet welded lap specimens in this study,and the weld seam cross-section hardness was *** experimental results show that most specimens mainly failed at the 7075 side weld toes even though the base material tensile strength of 7075 is higher than that of *** maximum stress-strain concentration in the two finite element models is located at the 7075 side weld toe,which is basically consistent with the actual fracture *** weld zone on the 7075 side experiences severe material softening,with a large ***,the Vickers hardness value on the 6061 side negligibly changes and fluctuates around 70 *** obvious defects are found on the fatigue fracture,but a large number of secondary cracks *** germinate from the weld toe and propagate in the direction of the plate *** reinforcement has a serious impact on fatigue *** life will decrease exponentially as the weld reinforcement increases under low *** is found that the notch stress method can give a better fatigue life prediction for TIG weldments,and the errors of the predicted results are within the range of two factors,while the prediction accuracy decreases under low *** equivalent structural stress method can also be used for fatigue life prediction of TIG weldments,but the errors of prediction results are within the range of three factors,and the accuracy decreases under high stress.

关键词： TIG welding notch stress method equivalent structural stress method fatigue life finite element analysis

Enhancing Deepfake Detection:Proactive Forensics Techniques Using Digital Watermarking

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Computers, Materials & Continua 2025年第1期82卷 73-102页

作者： Zhimao Lai Saad Arif Cong Feng Guangjun liao Chuntao Wang School of Automation Guangdong University and TechnologyGuangzhou510006China School of Immigration Administration(Guangzhou) China People’s Police UniversityGuangzhou510663China Department of Mechanical Engineering College of EngineeringKing Faisal UniversityAl Ahsa31982Saudi Arabia Cyber Police Division Guangzhou Public Security BureauGuangzhou510030China School of Forensic Science and Technology Guangdong Police CollegeGuangzhou510320China College of Mathematics and Informatics South China Agricultural UniversityGuangzhou510642China

With the rapid advancement of visual generative models such as Generative Adversarial Networks(GANs)and stable Diffusion,the creation of highly realistic Deepfake through automated forgery has significantly *** paper examines the advancements inDeepfake detection and defense technologies,emphasizing the shift from passive detection methods to proactive digital watermarking *** detection methods,which involve extracting features from images or videos to identify forgeries,encounter challenges such as poor performance against unknown manipulation techniques and susceptibility to counter-forensic *** contrast,proactive digital watermarking techniques embed specificmarkers into images or videos,facilitating real-time detection and traceability,thereby providing a preemptive defense againstDeepfake *** offer a comprehensive analysis of digitalwatermarking-based forensic techniques,discussing their advantages over passivemethods and highlighting four key benefits:real-time detection,embedded defense,resistance to tampering,and provision of legal ***,the paper identifies gaps in the literature concerning proactive forensic techniques and suggests future research directions,including cross-domain watermarking and adaptive watermarking *** systematically classifying and comparing existing techniques,this review aims to contribute valuable insights for the development of more effective proactive defense strategies in Deepfake forensics.

关键词： Deepfake proactive forensics digital watermarking traceability detection techniques

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两种真菌对紫茎泽兰的致病性研究

天然产物研究与开发 2004年第5期16卷 399-402页

作者：向明廖薇侯若彤杨志荣四川大学生命科学学院成都610064

本文以紫茎泽兰离体叶片为材料 ,研究了从空气中分离得到的青霉属和曲霉属的两种真菌对紫茎泽兰的致病性和叶片细胞膜透性的影响。结果表明 ,两种真菌及其毒素均能在紫茎泽兰叶片上产生直径 2～5mm的局部坏死斑。叶片用毒素处理后 ,细... 详细信息

本文以紫茎泽兰离体叶片为材料 ,研究了从空气中分离得到的青霉属和曲霉属的两种真菌对紫茎泽兰的致病性和叶片细胞膜透性的影响。结果表明 ,两种真菌及其毒素均能在紫茎泽兰叶片上产生直径 2～5mm的局部坏死斑。叶片用毒素处理后 ,细胞膜透性增大 ,相对电导率分别可达 86 .2 5 %、94 .5 6 % ;K+ 和Na+ 渗漏量增大 ,且随着时间的延长和毒素浓度的增加而增高。

关键词：紫茎泽兰毒素叶片细胞兰叶致病性相对电导率离体叶片真菌坏死局部

High-temperature-tolerant flexible supercapacitors: Gel polymer electrolytes and electrode materials

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Journal of Energy Chemistry 2025年第1期100卷 426-457页

作者： Chong Peng Xinyi Huang Mingwei Zhao Shuling liao Quanhong Yang Nianjun Yang Siyu Yu School of Chemistry & Chemical Engineering Southwest University Nanoyang Group Tianjin Key Laboratory of Advanced Carbon and Electrochemical Energy Storage School of Chemical Engineering and Technology and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) Tianjin University Department of Chemistry & IMO-IMOMEC Hasselt University

The development of flexible supercapacitors(FSCs) capable of operating at high temperatures is crucial for expanding the application areas and operating conditions of supercapacitors. Gel polymer electrolytes and electrode materials stand as two key components that significantly impact the efficacy of hightemperature-tolerant FSCs(HT-FSCs). They should not only exhibit high electrochemical performance and excellent flexibility, but also withstand intense thermal stress. Considerable efforts have been devoted to enhancing their thermal stability while maintaining high electrochemical and mechanical performance. In this review, the fundamentals of HT-FSCs are outlined. A comprehensive overview of state-of-the-art progress and achievements in HT-FSCs, with a focus on thermally stable gel polymer electrolytes and electrode materials is provided. Finally, challenges and future perspectives regarding HT-FSCs are discussed, alongside strategies for elevating operational temperatures and *** review offers both theoretical foundations and practical guidelines for designing and manufacturing HT-FSCs, further promoting their widespread adoption across diverse fields.

关键词： Polymer membrane electrodes

Recent advances in crystalline carbon nitride for photocatalysis

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Journal of Materials Science & Technology 2021年第32期91卷 224-240页

作者： Jingjun Liu wei Fu Yulong liao Jiajie Fan Quanjun xiang Yangtze Delta Region Institute(Huzhou)&School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaHuzhou 313001China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450002China

Semiconductor photocatalytic technology has become one of the most important means to solve the current energy shortage and environmental pollution. Compared with the traditional photocatalysts, graphite carbon nitride has a wider range of light-harvesting and more stable physical and chemical properties. However, traditional thermally induced polymerization of nitrogen-containing precursors produces the melon-based carbon nitride solids with an amorphous or semi-crystalline structure, resulting in low conductivity and moderate photocatalytic activity. Recently, crystalline carbon nitride has attracted more and more attention in improving photocatalytic performance. Some significant progress regarding crystalline carbon nitride for the preparation of solar-fuel and environmental purification has also been *** review describes the recent advances in the design and synthesis of crystalline carbon nitride photocatalysts. A brief description of the unique physical and chemical properties of crystalline carbon nitride was given. Later, the synthetic and modification strategies are being introduced. Then, the photocatalytic application of crystalline carbon nitride was discussed, mainly including photocatalytic H2 production,photocatalytic CO2 reduction, and photocatalytic degradation of pollutants. Finally, the challenges and future directions of crystalline carbon nitride photocatalysts are briefly introduced.

关键词： Crystalline carbon nitride Design and synthesis Photocatalytic H_(2)production CO_(2)reduction Photocatalytic degradation

Effects of water level variations on the water quality of Huayang Lakes, China

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Journal of Geographical Sciences 2025年第1期35卷 173-188页

作者： AN Lesheng LIU Chun FAN Zhongya liao Kaihua WANG Wencai WANG Nan School of Resources and Environment Anqing Normal University South China Institute of Environmental Sciences Ministry of Ecology and Environment The Key Laboratory of Watershed Geographic Sciences Nanjing Institute of Geography and LimnologyCAS

To explore water level variations and their dynamic influence on the water quality of Huayang Lakes, the water level from 1967 to 2023 and water quality from 2015 to 2023 were analyzed using the Mann–Kendall trend test, box plots, and violin plots. The results show a notable hydrological rhythm of water level alternation between dry and flood seasons in Huayang Lakes, with an average water level of 12.82 m and a monthly range of 11.21–17.24m. Since 2017, the water level of Huayang Rivers has shown a decreasing trend of –0.02 m/*** phosphorus(TP) has become the primary pollutant. The TP concentrations in Longgan Lake(the largest lake) during the dry, rising, flood, and retreating seasons from 2015 to 2023were 0.083, 0.061, 0.050, and 0.059 mg/L, respectively. The effect of water level on TP was mainly observed during the low-water period. When the water level in the dry season rose to 12.25 and 13.00 m, the percentage of TP exceeding 0.1 mg/L in Longgan Lake decreased to 55.8% and 33.3%, respectively. During the dry season, wind and wave disturbances caused the release of endogenous phosphorus in Huayang Lakes. This led to drastic fluctuations in TP concentration, reducing the correlation between water level and TP. When external control is limited, the water level during the dry season should be maintained between 12.25 and 13.0 m. Additionally, it is necessary to accelerate the restoration of submerged macrophyte species(such as Hydrilla verticillata and Vallisneria natans) in the Huayang Rivers.

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