bluuebunny/crossref_metadata_2025_split huggingface dataset:
Study on the influence of Hf, Zr and Mo elements on the mechanical properties of equimolar TiVNbTa refractory high-entropy alloy
Authors: Wu Gang , Xu Ziqi 
Published: September 2023

Abstract
The addition of alloying elements would improve the properties of refractory high-entropy alloys at room temperature and high temperatures. Hf, Zr and Mo elements were added in TiVNbTa refractory high-entropy alloys. Mechanical properties and microstructures after deformation were studied through compressive and tensile tests and microstructural characterization. Hf, Zr and Mo elements would increase the ambient strength of TiVNbTa alloy owing to increased atomic size difference and shearing modulus difference. However, Zr and Mo would deteriorate the ambient ductility, and Hf and Zr would decrease the high-temperature strength owing to lower shearing modulus and melting points. Moreover, the Zr-enriched BCC phase would precipitate after compression at 1000°C.
Study on preparation process and seawater corrosion resisting properties of chopped CF/PEEK composites
Authors: Zhu Hao , Li Yong 
Published: September 2023

Abstract
CF/PEEK composite material is widely used in marine engineering construction due to its characteristics of lightweight, high strength, corrosion resistance, and aging resistance, and it will inevitably produce side materials and wastes in the forming process. Therefore, the research on CF/PEEK recycling is of great significance. Due to the characteristics of PEEK’s high melting point and high viscosity of the solution, it is difficult to recycle and reuse such materials. In this paper, a certain amount of PEEK resin powder is added to improve the hot pressing technology of the chopped prepreg. Through a simulated seawater corrosion experiment, the influence of simulated seawater corrosion on the microstructure and mechanical properties of the composite materials is studied. Combined with the principal component analysis method, the corrosion resistance of the chopped CF /PEEK composite was evaluated comprehensively, which provided a reference for the recycling of thermoplastic prepreg and thermoplastic composite products. The results show that the surface quality and mechanical properties of the composites with resin powder are obviously improved. The resin matrix on the surface of the sample was subjected to salt corrosion by chloride ions in a simulated seawater solution to form local corrosion, resulting in pores, cracks, and other defects. The longer the corrosion time of simulated seawater is, the more serious the surface damage of the composite material is, and the more obviously the mechanical property declines. Principal component analysis showed that the resin content had little effect on the seawater corrosion resistance of chopped CF/PEEK composite.
Forming Performance of Multi-way Tubes in Hydroforming
Authors: Meng Zhenpeng , Liu Jianwei , Wang Binhao 
Published: September 2023

Abstract
The tube hydroforming technology is a rapid-forming technique in multi-way tube integrated and lightweight manufacturing. The forming performance of the multi-way tube under this technology was comprehensively analyzed and summarized in this paper. Firstly, the influencing factors, such as axial feed loading path and internal pressure, forming friction, and die transition fillet, in the process of multi-way tube forming were analyzed and summarized. Secondly, the optimization method of the multi-way tube forming performance in hydroforming was analyzed. Finally, the reduction of hydraulic expansion costs and the development of new hydroforming technologies were expounded.
The optimization of thermo-compression process parameters of continuous carbon fiber reinforced PEEK composites
Authors: Ma Xiaolong , Wen Lihua , Wang Shiyu 
Published: September 2023

Abstract
Thermoplastic composites with high performance have become the primary material developed for aerospace applications. However, there are still numerous challenges for high-quality thermo-compression molding of thermoplastic composites. This paper investigated the control mechanism of porosity in continuous carbon fiber (CCF) reinforced polyether-ether-ketone (PEEK) composites based on an orthogonal molding scheme, which examines the effect of thermo-compression process parameters on porosity. Further insights were obtained regarding the correlation among molding process parameters, porosity, and mechanical properties. The experimental results indicated that the significant factors affecting the bending performance of CCF/PEEK composites were molding pressure, temperature, and sequence holding time. Moreover, the viscosity of molten PEEK resin significantly affected the porosity of the composites, and the descending order of effect on the porosity of the composites was molding temperature, holding time, and molding pressure. Based on these results, we identified the optimal molding process conditions for CCF/PEEK composites, which were 405 °C, 1.5 MPa, and 30 min.
Study on interface bonding performance of honeycomb reinforced polyurethane composite molding structure
Authors: Wang Min , Ding Wuxue , Han Jingwei 
Published: September 2023

Abstract
Honeycomb reinforced polyurethane composite structure has excellent performance and has been used in more interior and exterior parts. Based on the integrated molding technology of honeycomb-reinforced polyurethane composite structure and skin fabric, three important factors affecting the interface bonding performance are proposed, the orthogonal test scheme is designed, and the process parameters of the product applied to the battery cover of the new energy vehicles are optimized and verified by taking the flat tensile strength as the index. The results show that the test can obtain the best process parameters, effectively improve the interface bonding performance of composite products, and can be used to guide the production and preparation of new energy vehicle battery cover products.
Synthesis and Performance Study of pH/Magnetic Dual Response Chitosan Based Emulsifiers
Authors: He Runna , Sun Shuangqing , Wang Zhikun , Hu Songqing 
Published: September 2023

Abstract
Recently, stimuli-responsive emulsions have been widely applied due to their excellent structural stability, biocompatibility, and environmental friendliness. For this application, the emulsion needs to be able to respond quickly to environmental stimuli with controlled stabilization and destabilization. This paper reports a novel composite Pickering emulsifier using Fe3O4 as the core, silica as the intermediate layer, and chitosan as the outer shell, which possesses a pH/magnetic dual responsive feature when deionized water is used as the water phase, and liquid paraffin is used as the oil phase to form an emulsion. Fe3O4@SiO2@chitosan has good paramagnetism and pH responsiveness to realize controlled magnetic and pH-responsive breaking of an emulsion when needed. The size of the composite emulsifiers ranged from 90 nm to 120 nm. The strong magnetic responsiveness enables rapid emulsion breaking at pH=3-11. When used as stabilizer particles, the chitosan shell behaves differently depending on pH. At pH≤2, fully protonated chitosan as the free chain segment and Fe3O4@SiO2 stabilized emulsions together. The overall stabilization of the emulsion (Fe3O4@SiO2@chitosan as emulsifier) can be obtained at pH>2, and emulsion breaking is achieved at pH≈pKa condition.
Study on the Effect of ELID Grinding on corrosion wear properties of Co-Cr Alloy
Authors: Li Jiwu , Zhang Hui 
Published: September 2023

Abstract
Contemporary Co-Cr alloys used in artificial joints can cause health complications in long-term applications. A pin-on-disc friction and wear testing instrument was used to evaluate the corrosion and abrasion of two types of Co-Cr alloys for artificial joints under simulated body fluid conditions after surface electrolytic composite grinding. Co-materials with lower carbon content displayed superior corrosion resistance than those materials with higher carbon content. Moreover, surface processing with electrolytic composite grinding produced a stable surface modification layer, which improved the surface hardness and formed an oxide film that inhibited metal ionization. The formation of precipitates in the corrosive environment is likely to improve the friction and wear properties of the material. As such, a variety of hardness was observed for the artificial joint friction disc and pin, especially when the hardness of the disc was higher than that of the pin, which can improve the friction and wear behavior of joints.
The Effect of Laser Cladding Lap Ratio of TC4 Alloy on Microstructure and Properties of Ni60 Coating
Authors: Wang Fei , Li Xiao , Peng Jiahui , Liu Zengzhi , Feng Xinyi 
Published: September 2023

Abstract
For improving wear resistance and hardness, Ni60 coatings were applied to TC4 alloy using laser cladding techniques. The effects of different lap ratios on the microstructure, microhardness, and wear resistance of the Ni60 coating were analyzed using an ultra-deep field microscope, XRD, microhardness tester and wear testing machine, and a suitable lap ratio was sought to obtain a coating with a better performance. The results showed that the Ni60 coatings with a 30% lap ratio had the best morphology and no obvious defects. From the bottom to the top, there are coarse columnar crystals, fine columnar crystals, equiaxed crystals, and acicular crystals, mainly composed of γ-Ni and some Cr7C3 and Cr23C6 phases. Therefore, the suitable lap ratio is 30%, and the microhardness of the coating at this parameter is 900 HV, which is about 2.5 times of the substrate (360 HV). The wear amount of the coating is 5.05 mg, which is about 11% of the substrate (44.23 mg). The average friction coefficient of the coating is about 0.41, which is 63% of the substrate (0.65). TC4 alloy’s wear resistance and microhardness can be significantly improved by applying suitable coating material and laser cladding parameters.
Study on effects of ultrasound on microstructure refinement at semi-solid statement of ultrasonic-assisted brazing SiCp/Al composites
Authors: Liang Jindi , Ma Lin , Zhu Chao , Zhou Changhzhuang , Zhu Zhi , Wang Chunxia 
Published: September 2023

Abstract
Ultrasonic composite brazing uses ultrasonic cavitation and acoustic flow effects to ameliorate the soakage property of SiC particles and brazing material, enabling flux-free brazing of SiCp/Al-MMCs under atmospheric conditions. However, its mechanical properties are limited by the performance of the brazing material, which is often difficult to apply in structures with high strength requirements. In order to break through the limitations of conventional ultrasonic composite brazing of SiCp/Al-MMCs, this paper uses 50 vol.% SiCp/Al MMCs as base material and Zn-16Al brazing material. It applies secondary ultrasound at different times during the solidification of the liquid brazing material to reduce the weld grain size and reinforce the weld intensity by using ultrasonic cavitation and acoustic flow effects. The results show that the addition of secondary ultrasound can reduce the α-Al size and make the SiC particles and α-Al evenly distributed in the joint, which can significantly reinforce the intensity of the weld. The shear performance enhanced with the increase of supersound application second, but too long secondary sonication caused atomization of the brazing material, resulting in unfilled brazing material in the weld, which seriously affected the properties of the weld.
Time-depending Reliability Analysis of O-ring Sealing Performance
Authors: Zhang Jie , Ma Yong , Xie Liyun 
Published: September 2023

Abstract
O-rings are commonly used due to their simple structure and excellent performance. However, the time-dependent creep behavior of rubber during usage can significantly impact the working performance and service life of the O-ring. The phenomenological creep constitutive model establishes a relationship between the deformation of rubber materials under creep conditions and time, by incorporating a creep function that considers the significance of damage. Based on the phenomenological creep constitutive model, we establish a simulation model for the contact pressure of an engine O-ring. This model characterizes the time-dependent degradation process of the O-ring’s sealing performance by tracking the variation of contact pressure and contact surface width over time. To account for the randomness of rubber material model parameters and compression amount, we develop a time-dependent reliability analysis model for the O-ring using the first-order second-moment (FOSM) method. The research findings can establish a theoretical foundation for the assessment, analysis, and evaluation of O-ring sealing’s time-dependent reliability.
The adsorption of U(VI) by persimmon tannin modified aminated polyacrylonitrile fiber
Authors: Wu Fan , Xie Shuibo 
Published: September 2023

Abstract
In this study, a green and efficient persimmon tannin functionalized polyacrylonitrile fiber (PAN-TETA-PT) was prepared and used to treat U(VI). The influence of pH value, adsorption temperature and time, and fiber material dosage on the adsorption U(VI) of PAN-TETA-PT fibers were investigated, and the kinetics, isotherm, and thermodynamics of fibers were analyzed. When the pH is 6, the temperature is 30°C, and the fiber dosage is 0.2 g·L−1, the adsorption rate of PAN-TETA-PT fibers to U(VI) was 96.5%, and the U(VI) adsorption capacity was 159.75 mg/g. The kinetic and isothermal studies show that the adsorption of PAN-TETA-PT fibers to U(VI) is chemisorbed and multilayer adsorption. The thermodynamic analysis reflects that the PAN-TETA-PT is spontaneously endothermic for the adsorbed U(VI).
Characterization on chain-assembly of polystyrene micro-particles via dielectrophoresis
Authors: Zheng Xiongbiao , Huan Zhijie , Ma Weicheng , Chen Zexiang , Zhang Zhemin 
Published: September 2023

Abstract
In this paper, the characteristic of pearl chain formation was investigated with the dielectrophoretic manipulation of polystyrene micro-particles. Comsol-based simulations and dielectrophoretic experiments were conducted to analyze the detailed influence factors. With different parameters such as voltage amplitude and particle size, the length of the pearl chain varies. Simulation results are consistent with experimental results, indicating that voltage amplitude is a critical factor for chain formation, while particle size has minimal impact. Additionally, particle chains exhibit slight orientation differences between the experiment and simulation. These results provide significant insight into the behavior of chain formation under the influence of dielectrophoresis and offer practical guidance for implementing dielectrophoresis technology in microfluidic chips and biosensors.
Checkered Clusters Forming Mechanism Design
Authors: Yang Dingyong , Wang Bo , Lu Zhengjie , Wu Peiheng , Liang Yongge 
Published: September 2023

Abstract
As an important and widely used tool in the process of mulberry silkworm breeding in China, the wooden checkered clusters have the advantages of a high cocooning rate, good reliability, and good water absorption. For the moment, wooden checkered cluster production is still dominated by manual assembly. Such production methods are inefficient. In light of this problem, this paper designs a kind of automatic wooden checkered clusters machine based on the standard for wood grid clusters with a length of 530 mm, a width of 355 mm, and a grid number of 12 * 24. The main structure of the machine includes four parts: a checkered clusters mold conveying mechanism, a checkered clusters sheet loading mechanism, a checkered clusters sheet pressing mechanism, and a square cluster mold. The finite element analysis of the crankshaft (circulating downward press checkered clusters sheet) of the main part ball screw (transferring power) is carried out, and the results meet the design requirements. The machine uses a programmable controller (PLC) to achieve precise control and real-time detection of the actions of all aspects of the machinery to ensure long-term operation of mechanical energy and to produce a wooden checkered clusters machine with excellent quality and stability, which improves the production efficiency of the checkered clusters by three times.
Theoretical study of sound absorption performance for Al2O3-polyurethane foam composite
Authors: Yuan Binxia , Hou Weiguang , Liu Jianben , Zhou Bing , Cao Lan 
Published: September 2023

Abstract
To reveal the sound absorption property and mechanisms of Al2O3-polyurethane (Al2O3-PU) composite materials in theory, the impedance tube model is established by using the finite element method in this paper. Meantime, the theoretical modal and the calculation method adopt the Johnson-Champoux-Allard (JCA) modal and the standing wave ratio method, respectively. By comparing the experimental and simulation values of PU and Al2O3-PU composites from 0 to 1250 Hz, the results prove that the JCA predicted values can match the actual measured values. To further predict the sound property of Al2O3-PU composites in the medium and high frequency, the diameter of 29 mm and length of 600 mm for the impedance tube is installed. Finally, the sound pressure distribution diagram of the impedance tube is obtained.
Simulation And Design of a Vertical Gallium Nitride JFET with Dual Lateral Heterojunction Channels
Authors: Huang Hao , He Wei , Yang Jiaying , Zheng Ziyang , Peng Fangxi 
Published: September 2023

Abstract
A novel vertical gallium nitride (GaN) junction field-effect transistor (JFET) is reported in this article. Through the setup of dual lateral heterojunction channels in the body, the current density is high while the p-type gallium nitride growth area can be adjusted to easily achieve enhanced mode. Based on the structure parameter settings in this article, through the device simulation software TCAD, and under the condition of selecting the appropriate p-type GaN growth region, the threshold voltage of the device is 1.1 V, the source output current density can reach 7.2 kA/cm2, the breakdown voltage is about 750 V, and the on-resistance is 0.52 mΩ·cm2. Finally, the test circuit is built, and the switching characteristics of the device proposed in this paper are simulated under the consideration of parasitic inductance.
Insights of the pH-dependent emission of carbon dots: a density functional theory study
Authors: Pan Yuye 
Published: September 2023

Abstract
The mechanism of luminescence in carbon dots has long been a topic of controversy, as accurately characterizing their structure has proven difficult. This has made it challenging to guide the design and synthesis of carbon dots, hindering the development of highly efficient fluorescent varieties. Understanding the mechanism and regulatory mechanisms of carbon dot luminescence at the molecular level is important not only from a theoretical perspective but also has practical value. Previous studies have suggested that the fluorescence emission wavelength of carbon dots can be altered by changing the pH of the carbon dot solution, but the mechanism behind this modulation is not yet fully understood. In this study, we used density functional theory calculations and excited state simulations with 2, 3-Diaminophenazine, a representative luminescent molecule found in molecular state luminescent carbon dots, to investigate the effect of protonation on the absorption and fluorescence emission spectra of carbon dots. We analyzed the electronic structure and spatial distribution of the luminescent molecules before and after protonation and found that the change in molecular dipole moment caused by protonation was responsible for the significant red shift in the fluorescence spectrum. To further verify our findings, we modified the substituted functional groups with different electron-pulling abilities in the corresponding luminescent molecules to modulate the molecular dipole. The results showed that the larger the dipole moment in the luminescent molecules with different substituted functional groups, the longer the fluorescence emission wavelength. Therefore, the protonation-induced change in molecular dipole is the main reason for the pH-dependent modulation of luminescence in molecular state luminescent carbon dots.
Experimental study on the removal of U(VI) from wastewater by chitosan modified with persimmon tannin
Authors: Zhang Haibo , Xie Shuibo 
Published: September 2023

Abstract
Persimmon tannin modified chitosan (PT-CS) microspheres were synthesized by a water bath method using sodium tripolyphosphate (STPP) as a cross-linking agent for the removal of U(VI) from wastewater. The results showed that the optimal preparation conditions for PT-CS were a ratio of PT to CS mass of 4:1 and a reaction temperature of 80°C. When the initial concentration of U(VI) was 5 mg/L, and the pH value was 1.5, the PT-CS was injected at 0.06 g/L, and the reaction was 2.5 h. The removal rate of U(VI) from water reached 99.2%. The results of the deep removal test of U(VI) from rare earth wastewater showed that the concentrations of U(VI) in the combined wastewater and extraction wastewater were reduced from 4.42 mg/L and 2.12 mg/L to within 0.02 mg/L at pH 2.0, respectively. In contrast, the removal rate of high concentrations of Ca2+ in the wastewater reached 99%, meeting the emission standards of the rare earth industry.
Design and Simulation Analysis of Parallel Manipulator
Authors: Zhang Xiaokang , Wang Weiru , Geng Kaizhen , Yang Jianjun 
Published: September 2023

Abstract
With the rapid development of domestic manufacturing, industrial robots have become widely used and become a research hotspot. In this paper, the classical three-degree-of-freedom parallel manipulator is taken as the analysis object, the plane three-degree-of-freedom parallel positioning platform is designed, its kinematics model is established, and the dynamic simulation analysis is carried out in ADAMS software, and the drive motor is selected according to the simulation results.
Design of a New Method for Oxidizing Polypropylene Wax through the Scraper Reactor and Its Characterization
Authors: Li Chenyang , Xiang Nan , Wang Chuanxing 
Published: September 2023

Abstract
In this paper, a new scraper reactor is developed to oxidize polypropylene wax, and the reactor is studied through the characterization of the product. Compared with the traditional polyolefin wax high-pressure reactor, the scraper reactor made all samples heated evenly through the outer wall heating, effectively avoiding the problem of inconsistent reaction progress caused by uneven heating. The scraper constantly updates the interface, making the product fully in contact with the air and ensuring the atmosphere conditions for introducing polar groups. The scraper reactor not only simplifies the reaction conditions greatly but also saves the cost of oxidation. The scraper reactor replaces the traditional high-pressure stirring reactor, the membrane scraper in the reactor replaces the traditional stirring, and the air is used as the oxidant. A one-step reaction could obtain high-quality oxidized polypropylene wax (OPPW). The reaction time and temperature effects on OPPW products in new oxidation equipment are discussed. Through oxidation reaction, polar groups such as -C=O and -COOH are introduced into PPW to perform better in the polar environment and improve its thermal stability.