bluuebunny/crossref_metadata_2025 huggingface dataset:
Janus MoSSe monolayer coordinated single B atom as an efficient catalyst for nitrogen reduction to ammonia
Authors: Yuan Saifei , Ren Hao , Zhu Houyu , Guo Wenyue
Published: December 2022

Electrochemical nitrogen fixation under ambient conditions is an energy-saving and environmental-friendly method alternative to the Haber-Bosch process, but is subjected to efficient electrocatalysts. Through density functional theory (DFT) computations, we systematically investigate the NRR performance of single B atom substitution S and Se atom in the Janus MoSSe monolayer (BSMoSSe and BSeMoSSe) as a single atom catalyst (SAC). The results show that BSMoSSe and BSeMoSSe are promising catalysts with a low energy barrier of 0.10 eV and 0.27 eV and excellent NRR selectivity. Charge density differences confirmed the N2 activation mechanism of acceptance-donation between B and adsorbed N2. These findings bring a new strategy for NH3 production by BSMoSSe and BSeMoSSe electrocatalysts under ambient conditions.
Research on behavior mechanism and performance of concrete shrinkage reducing agent
Authors: Lin Yanmei
Published: December 2022

The research on the function and mechanism of shrinkage reducing agent shows that shrinkage reducing agents can greatly reduce the shrinkage rate of concrete without adversely affecting the mechanical properties of concrete. The mechanism of the shrinkage-reducing agent was tested and analyzed from the water evaporation rate of the solution and the surface tension of the solution. The results showed that the addition of the shrinkage reducing agent could significantly reduce the surface tension of the aqueous solution, and had little effect on the evaporation rate of the water on the surface of the aqueous solution; the surface tension test shows that the mechanism of shrinkage reducing agent reducing drying shrinkage is mainly to reduce the surface tension of pore solution; the analysis from the water evaporation rate test shows that shrinkage reducing agent has no significant effect on water evaporation inhibition, and inhibiting concrete moisture evaporation is not the most commonly used shrinkage reducing agent reduction mechanism.
Preparation and characterization of La2-xSmxMo1.8Al0.2O8.7 as electrolyte for solid oxide fuel cells
Authors: Tian Changan , Shao Lingbo , Chen Chao , Liu Yang , Wang Cao , Zhu Lejie
Published: December 2022

Solid oxide fuel cells (SOFCs) have been regarded as promising eco-friendly power sources in recent years owing to their high energy conversion efficiency and fuel flexibility. La2Mo2O9-based ceramics draw researchers’ attention due to their good performance as electrolyte materials for SOFCs. In this study, the Sm and Al co-doped La2Mo2O9, La2-xSmxMo1.8Al0.2O8.7 (x=0.1,0.2,0.3 and 04, LSMAO), are successfully synthesized by the sol-gel method as electrolyte materials for SOFCs. The phase evolution, sintering, the microstructural and electrochemical performance of LSMAO were observed by TG-DSC, XRD, SEM, and impedance analyses, respectively. The results show that the highly phase-pure cubic LSMAO nanopowders can be obtained after calcining at 600 °C for 2 h. The as-synthesized LSMAO powders exhibited a better sintering activity. All these samples were found to have a relative density above 94.5% after sintering at 950 °C for 5 h. The electrical performance study shows that higher doping concentrations of Sm caused a decrease in ionic conductivity and an increase in activation energy. La1.9Sm0.1Mo1.8Al0.2O8.7 exhibited the highest oxide ionic conductivity (σ800 °C=0.033 S/cm) and lowest electrical activation energy (Ea=0.85 eV). This shows that LSMAO could be used as a potential electrolyte for intermediate temperature SOFCs (IT-SOFCs).
Study on corrosion fatigue behavior of heavy piece Ti6Al4V titanium EBW joint in artificial seawater
Authors: Wang Chunyan , Zhang Yupeng
Published: December 2022

Titanium alloy has been more and more used in the ocean engineering field. Since the crucial service environment, the corrosion fatigue behavior of the Ti6Al4V alloy EBW joint has been investigated and analyzed. The results show that the grain size of the molten zone decreases gradually from the central line to the base metal symmetrically and the acicular α’ martensite and β phase grain boundaries are the dominating phases of the seam zone. Moreover, the corrosion fatigue crack growth rate of the seam zone was insensitive to the texture of the base metal and crystal orientation of the ti6al4v alloy. It could also be seen that the base metal and the seam zone have different crack growth mechanisms, which is mainly during to the existence of the acicular α‘ martensite in the seam zone and the trend of crack tip energy release. The crack propagation rate of the seam is lower than that of the base metal.
Study on zinc slag defects on surface of pure hot dip galvanized steel sheet
Authors: Ding Xin , Feng Huixiong , Zhao Chuanxiang
Published: December 2022

Hot dip galvanized steel sheet is widely used in the automotive field because of its advantages of low cost, thick hot dip galvanized layer, reducing body defects, improving vehicle performance, and beautifying surface appearance. However, the zinc slag defects on the surface of the steel plate significantly reduce the surface quality of the steel plate. In this paper, the morphology of zinc slag on the surface of a pure hot-dip galvanized steel sheet was analyzed by scanning electron microscope. The results showed that the zinc slag defects on the surface of pure hot-dip galvanized steel strip was round, and the size was large, about 700 um. By adjusting the air knife pressure, the aluminum content in the zinc tank, and the opening of the RCS fan, the number and size of zinc slag defects on the surface of pure hot-dip galvanized steel strip can be significantly reduced. As a result, the steel plate was improved.
Effects of a porous boron nitride nanofiber on nano-mechanical properties in shallow surface of WC-Si3N4 composite
Authors: Cao Ting , Li Xiaoqiang
Published: December 2022

The nanoindentation technique has been applied to materials research for decades, such as WC, Si3N4, and other ceramics or composites. However, nano-mechanical properties in shallow surfaces were often unstable, especially for ceramics-based composites. In this paper, the mechanical properties of WC-10 wt.% Si3N4 without and with the addition of ultrafine porous boron nitride nanofiber were investigated by nanoindentation continuous stiffness measurement in this study. The effects of the porous fiber on elastic modulus and hardness were revealed, which led to more stable and regular profiles of the elastic modulus and hardness versus displacement curves. The curves were cut out and shown before the 30 nm displacement of the tip, which displayed the regularity of the profiles caused by the porous fiber more directly. The values were statistically analyzed at intervals of 10 nm after 30 nm displacement, and then lower standard deviations were observed. The different Si3N4 cracks made from Vickers indentation on the composites were photographed and associated with the regularity of the curves after the fiber addition. It’s considered that the regularity effects on mechanical properties of the porous boron nitride nanofiber on ceramics composites can be helpful in thin film studies, which are also in difficulties of mechanical properties scattering on the nanometer scale using continuous stiffness measurement.
Study on hot deformation behavior of Mg-9Y-1MM-1Zn-0.6Zr alloy
Authors: Feng Lishuai , Ma Minglong , Zhang Kui , Li Yongjun , Li Xinggang , Shi Guoliang , Yuan Jiawei , Sun Zhaoqian
Published: December 2022

Rare earth elements and the LPSO phase play a significant part in the optimal regulation of the comprehensive performance of the Mg-9Y-1MM-1Zn-0.6Zr (WE91B) alloy, but the high strength of the alloy also brings problems such as difficulties in processing deformation. To determine optimal machining parameters suitable for WE91B, the homogenized alloy was investigated in constant temperature and equal rate compression using the Gleeble-3500 thermal simulation measurement instrument, to study the hot deformation behavior of WE91B alloy in the temperature range of 693-783 K, strain rates of 0.001-1s−1 and maximum deformation of 60%. The deformation activation energy was calculated, the constitutive equation of WE91B alloy was constructed, and the processing map of the alloy was established according to the dynamic material model. The results show that the flow stress curves of the alloy exhibit typical dynamic recrystallization characteristics and the flow stress increases significantly with the increase in strain rate and decrease in deformation temperature. The hot deformation activation energy of WE91B alloy is about 331.605 kJ/mol. From the two aspects of processing map and microstructures after plastic deformation, the optimal processing process of WE91B alloy is T = 783 K and έ = 0.05 s−1.
Research on Dynamic Mechanical Properties of Different Silane Coupling Agent In-situ Modified SSBR/Silica Composites
Authors: Wu Xiaohui , Xu Qing , Zheng Tao , Niu Qiqiang , Hou Cong , Shao Hongqi
Published: December 2022

Hydroxyl density of silica surface will reduce and the compatibility of silica with rubber matrix will be improved through the modification of silica by silane coupling agent (SCAs). The silica-silica and silica-rubber interaction of silica filled solution polymerized styrene butadiene rubber (SSBR) in-situ modified by silane coupling agent TESPT and Si747 are studied by Dynamic Mechanical Analyzer (DMA). The effect of different types and loading amounts of SCAs on the dynamic mechanical properties of silica filled SSBR is investigated. The results show that the novel silane coupling agent Si747 has a more apparent effect on lessening the silica network than that of silane coupling agent TESPT, Hysteresis factor (tanδ) measured by DMA reduces, and the heat-built improves. It could also be found that Si747 modified composites have the lowest apparent activation energy, which is used to characterize the filler-rubber interaction, indicating the lowest temperature dependence.
New Two-Dimensional WS2/ZrSi2N4 Heterostructure as photocatalyst for Water Splitting into Hydrogen
Authors: Ma Hao , Guo Wenyue
Published: December 2022

Heterostructure construction is an important strategy for separating photogenerated electron-hole pairs and enhancing optical absorption ability of photocatalysts. In this work, we performed WS2/ZrSi2N4 heterostructure calculations about its structural and electronic properties based on the density functional theory. Our calculations show that BB2-stacking is most stable in all possible stacking configurations of WS2/ZrSi2N4 heterostructure. In addition, the charge transfer route of type-Z scheme is observed for the WS2/ZrSi2N4 heterostructure, which is beneficial for separating the electron-hole pairs and suppressing the carrier recombination. The stronger optical absorption ability of the WS2/ZrSi2N4 heterostructure is maintained compared with individual WS2 and ZrSi2N4 monolayers. These results suggest that the WS2/ZrSi2N4 heterostructure maybe is the potential for photocatalytic water splitting in hydrogen applications.
Investigation of the main factors affecting the magnetic properties of silicon steel sheets by comparing three kinds of silicon steel
Authors: Zeng Jianhui , Li Liejun , Gao Jixiang , Huo Xiangdong , Peng Zhengwu
Published: December 2022

As an important magnetic material, silicon steel is widespread used in various motors, generators, relays and transformers. It is of great significance to explore the factors affecting the magnetic properties of non-oriented silicon steel. This paper introduces the production process of 50W800, 50W600 and 35W550 non-oriented silicon steel, and compares their magnetic properties, observes the microstructure of silicon steel sheet under hot rolling, cold rolling and annealing three technological states, analyzes the influence of sheet thickness, composition, microstructure and impurity on the magnetic properties of non-oriented silicon steel. The results can be summarized as follows: (1) The magnetic properties of the silicon steel sheet can be improved to a certain extent by reducing the thickness of the silicon steel sheet.(2) Increasing silicon content in a certain range can reduce core loss of silicon steel. (3) After annealing, the grain size of cold rolled silicon steel sheet becomes larger, the defect of grain decreases, the loss of iron core decreases, and the finished silicon steel sheet with good magnetic properties is obtained.
Molecular dynamics study of tensile properties of graphene/GaN heterostructures
Authors: Liu Dongjing , Zhu Jingjie , Zhou Fu , Zhang Guoqi , Yang Daoguo
Published: December 2022

Graphene/GaN nanocomposites have been widely used in high-power and high-frequency optoelectronic devices. At present, the thermal transport characteristics of graphene/gallium nitride heterostructures have been investigated by many scholars, but their mechanical properties have not been systematically studied. In this paper, the effects of graphene layer number, temperature and interfacial structure on the mechanical properties of graphene/GaN heterostructures were investigated by molecular dynamics method. The mechanical properties of materials were analyzed by failure stress, failure strain and Young’s modulus. The simulation results show that the heterogeneous structure is very sensitive to temperature. When the temperature is set at 2000K, the Young’s modulus of the heterostructure decreases by 25.11% compared with that at 300K, which indicates that the increase of temperature will reduce the mechanical properties of graphene composites, However, when the number of graphene layers increases, the mechanical properties of the heterostructures also improved. With the number of graphene layers is set from 1 layer to 5 layers, the performance of the heterostructure is improved, and its Young’s modulus increases by 48.46%. In addition, the effect of interface structure on the young’s modulus of the heterostructure structure is not obvious, but it will affect the maximum failure stress and maximum failure strain of the material. The mechanical properties of graphene in cross section contact with gallium atom are better than those of nitrogen atom. It is beneficial to improve the reliability of microelectronic devices to control and design heterogeneous structures based on the research results.
Study on the Coordination of Cd Ion with Perhydroxylated Hetero-N and Hetero-S Calixtetraarene Derivatives
Authors: Liu Yu , Wang Xiaofeng , He Liping , Meng Yanbin , Lan Wenbo , Wang Binbin , Yu Yao , Xie Qun
Published: December 2022

To explore the best hybrid calixarene for cadmium ion capture, the B3LYP method in density functional theory (DFT) was used to optimize the structure and infrared vibration data of the complexes formed by each fully hydroxylated heteroN and heteroS calixtetraarenes with Cd ions. The stability of the structure of each complex was verified. At the same time, the structural characteristics of each complex were analyzed. A comparative study on the binding ability of different numbers of hybrid calix [4] arene derivatives to Cd ions was carried out, and the complexes that best bound to Cd ions were obtained. For example, the binding capacity of hetero S-calix [4] arenes to Cd ions is greater than that of non-hybrid complexes and hetero-N complexes to Cd ions. More interestingly, as the number of S atoms in the hetero S increases, the binding ability to Cd becomes stronger.
Hexagonal sheet Ag and Ag nanoparticle inside 3D-TiO2 NTAs decorated Ti gauze by electrodeposition
Authors: Chen Chao , Liu Yang , He Tusheng , Tian Changan
Published: December 2022

Noble metal nanoparticles have attracted extensive attention by many researchers because of their optical, electrical and magnetic advantages. Half hexagon sheet Ag and Ag nanoparticles inside 3D-TiO2 nanotube arrays (NTAs) on Ti gauze was firstly synthesized by electrodeposition. The addition has a great influence on the morphology of Ag. When Ag hexagonal side length reached a maximum of 2 μm for 20 pluses, hexagonal Ag would transform oval Sphere with depositional pulses continuing increases, Ag nanoparticle inside 3D-TiO2 NTAs also were found, and the Ag modified NTAs for 20 pulses with the best photo-catalytic activity degraded methyl orange (MO) under solar light irradiation. Due to 3D-TiO2 NTAs supporting Ag catalyst, which is a benefit for recycling after the catalyst. This work is expected to provide a fundamental guide for the design of novel morphology catalysts on Ti gauze, which is conducive to recycling.
Doped single B atom on WS2 as a promising electrocatalyst
Authors: Xu Beixi , Hao Chunlian , Guo Wenyue
Published: December 2022

Ammonia (NH3) has the characteristics of large hydrogen content and high energy density, which is in line with the concept of green and low-carbon circular economic development. Since nitrogen (N2) sources are abundant on earth, they can be used to synthesize NH3. The critical step is breaking the N≡N bond (945 kJ/mol), and then activating N2. Today, industry requires the production of NH3 at the temperature as high as 300-500°C and the pressure as high as 150-300 atm, using metal catalysts such as iron (Fe) or ruthenium (Ru), which consumes plenty of energy. The electrocatalytic nitrogen reduction reaction is considered to be an alternative expected method for NH3 production under gentle conditions, in which the catalysis of the electrocatalyst plays a crucial role. The results indicate that N2 can be effectively enabled by B/WS2 and can accelerate the process which converts nitrogen gas into ammonia through an alternative mechanism of nitrogen reduction reaction (NRR) in a low limiting potential of -0.44 V. Furthermore, the as-designed catalyst performed highly thermodynamic stable, highly active, and highly NRR select. Thus, this work gives researchers a new perspective on N2 fixation by lower dimensional electrocatalyst materials under gentle conditions.
The lightweight design for the frame structure of FSEC
Authors: Ren Chun , Guo Xiang
Published: December 2022

Vehicle light-weighting is aimed at reducing the curb weight of the vehicle to ensure its strength, safety, and performance, as well as to reduce fuel consumption and exhaust emissions. The use of modern simulation technology in structural optimization design is one of the most important methods to achieve structural lightweight. In this paper, we study the size optimization of the frame structure based on the rules and requirements specified in Formula Student Eclectic China (FSEC), following the race’s rules and requirements, while satisfying the vehicle’s dynamic and static performance requirements. First, a three-dimensional geometric model of the frame structure is developed, and the static and dynamic performance of the frame is simulated using the finite element method. Next, structural size optimization is carried out under the premise of ensuring structural performance. Finally, the feasibility of the optimized structure is evaluated by comparing its performance before and after optimization. The research results show that the final frame structure has been reduced by 7.6 kg and the weight reduction has reached 22.4%. All performance indices meet the requirements of the competition, and a good lightweight effect has been achieved.
Analysis and research on the resonance of mobile phone shielding cabinet
Authors: Wen Shuhua , Fang Chen
Published: December 2022

In order to cut off the connection between the mobile terminal and mobile communication base stations or Wi-Fi, it is necessary to improve the electromagnetic shielding efficiency of the mobile phone shielding cabinet. This paper analyzes the resonant characteristics of mobile phone shielding cabinets. The test method of electromagnetic shielding has been introduced. Through Maxwell wave equation and boundary conditions, the cavity resonant frequency of every small drawer on the mobile phone shielding cabinet has been derived, and the rectangular cavity research model was established. Using the high-frequency finite element method (FEM) simulation to calculate the cut-off frequency of the first 10-order high-order mode in the cavity, the resonant standing wave field distribution of every small drawer on the mobile phone shielding cabinet has been analyzed. This paper can offer a theory instruction for the product design of mobile phone shielding.
Fracture Analysis of Butt Joint Girth Weld of Pipe and Flange
Authors: Xu Yan , Bi Liuhan , Liu Yinglai , Xu Tianhan , Feng Zhenjun , Bai Qiang , Yang Fengping
Published: December 2022

Duplex stainless steel has been widely applied to industry. In this paper, nondestructive testing, chemical composition analysis, metallographic analysis, hardness test, and scanning electron microscope were used to study the causes of the crack in the butt joint girth weld of pipe and flange. Both steel pipe and flange are duplex stainless steel S31803. Through analysis, it was judged that the crack was a crystalline crack, generated in the welding process, which was related to the welding process and the control of the welding installation gap between the steel pipe and the flange with unequal wall thickness.
Research on fatigue crack propagation life prediction method for subsea pipelines
Authors: Zhou Chenyan , Zhang Jianing , Zhang Yahong , Chen Jie
Published: December 2022

Subsea pipelines are subject to complex loading environments, and fatigue damage is one of the main failure modes. Due to manufacturing or environmental factors, crack defects are inevitable in submarine pipelines. For subsea pipelines in service, it is of practical importance to predict the residual fatigue life. On the premise of the conservative estimation method, the MTS criterion is used to analyze the crack propagation mode of subsea pipelines. In the numerical prediction method, the crack stress intensity factor is solved by the finite element method combined with the 1/4 node displacement method, and then the fatigue life of the subsea pipeline is predicted by the da/dN method based on the Paris formula. The results show that when the crack size increment Δa is set reasonably, the predicted results of crack propagation life of subsea pipeline are close to the experiment results, which verifies the accuracy of the numerical prediction method. The choice of the crack size increment has a large impact on the life prediction and needs to be considered in terms of both calculation accuracy and time consumption. The results obtained provide a reference for the safety assessment of pipelines in service.
Prediction of the Exposure Endpoint of Textile Color Fastness to Light
Authors: Zhang Huanhuan , Huang Yijing , Zhou Wei
Published: December 2022

The color fastness to light of textile in the product standard is always tested by method 3 in GB/T 8427, which determines the endpoint of exposure according to the discoloration of the blue wool standard sample. The aging of the xenon lamp for exposure resulted in the different sun exposure times of blue wool references required for the same color fastness level. As a result, the difficulty of testing increased, and the test accuracy was also affected. In this paper, the relationship between the exposure time and the service time of xenon lamps was studied through real-time monitoring to accurately predict the endpoint of textile light fastness. The exposure time for color fastness class 3 curve according to the service time of xenon lamp was fitted as: y1=10.4785+6.39539E−5x1+2.53603E−7x1
2; the exposure time of color fastness class 4 underexposure was fitted as: y2=38.17692-0.00131x2+2.78006E−6x2
2-4.81015E−10x2
3; the color fastness to light of textiles wetted with artificial perspiration was y3=13.78014-5.53089E−4x3+1.53274E−6x3
2-2.92228E−10x3
3+1.02685E−14x3
4. The method is practical and effective, has practical value for the light fastness testing of textiles, and has important guiding significance for daily light fastness testing in the future.
A molecular dynamics study on sintering behavior and densification characterization of nanocopper
Authors: Shi Jingmin , Xiao Wei , Wang Jianwei , Yang Hui
Published: December 2022

The technical problem of copper additive manufacturing is expected to be solved through the size effect of nanomaterials. The molecular dynamics method was employed to understand the laser sintering process of single-crystal copper nanoparticles. Based on a theoretical characterization of the densification of nanocopper sintering developed at present and the prediction of the melting point of nanocopper, the sintering and densification behaviors of copper nanoparticles with different sizes at different sintering temperatures were investigated. It is finally concluded that the densification of the nanocopper sinter can reach up to 95% under the condition of sintering temperature below the melting point of the nanocopper.
DR detection process analysis for weld of pressure-bearing special equipment
Authors: Chen Le
Published: December 2022

Due to the complex and harsh operating environment of pressure-bearing special equipment, the occurrence of accidents is very harmful, so its safety performance is very important. At present, the smelting and machining technology of related raw materials and components is very mature, but the toughness of the weld metal generally lags behind that of the base metal, which has become the weakest link in pressure-bearing special equipment. Especially in long-term operation under complex working conditions such as high temperature, high pressure, and vibration, it is easy to produce fatigue, corrosion defects, or cause the expansion of residual defects in manufacturing and installation. This paper will analyze and introduce the digital ray (DR) detection process of weld of pressure-bearing special equipment, and provide a certain reference for the correct use of digital ray technology.
Failure Analysis of Oil Pipe Fracture in Steam Turbine Oil Supply System of Power Plant
Authors: Chen Le
Published: December 2022

Oil pipe fracture of the steam turbine oil supply system of a thermal power plant is carried out by macro inspection, spectral analysis, metallographic analysis, hardness analysis, and scanning electron microscope analysis. The results show that the fractured tubing is a fatigue fracture, and the source of the crack is the fatigue crack formed by the stress concentration of the weld, which eventually leads to the fracture and leakage at the place.
Research on the agile management system of workshop production resources
Authors: Jia Limin , Mo ShanShan
Published: December 2022

Industry 4.0 has a key technical point that the intelligent factory uses the ‘ raw materials ’ containing information to complete the production tracking. The high-performance real-time positioning system is an important part of the real-time tracking and positioning of materials in the industrial Internet of Things. Passive Ultra High Frequency (UHF) Radio Frequency Identification (RFID) technology has become the preferred solution for the industrial 4.0 material real-time positioning system. This paper first analyzes the RFID positioning technology, gives the process architecture of workshop manufacturing resource RFID real-time information-driven production line and the classification and management scheme of multi-source real-time manufacturing information, and realizes the RFID tracking and positioning of workshop manufacturing resource.
Analysis of coiling stable roll of hot-dip galvanized strip
Authors: Lu Fangtao , Lin Zhijun , Lin Guoli , Murong Wei , Hu Faqi , Li Liejun
Published: December 2022

The coiling stable roll of hot-dip galvanized is a defect formed in the galvanizing process. The zinc slags and floating foreign matters in the zinc pot will directly or indirectly adhere to the roll surface of the stabilizer roll with the flow of zinc liquid. When the strip steel contacts the stabilizer roll, the zinc slag will extrude and deform the iron base plate and form pits. In this paper. The causes of the defects were analyzed. There were two methods to eliminate the coiling stable roll, that is, to reduce the generation and accumulation of zinc slags in the zinc pot. The main measures are first to control the temperature of the strip entering the zinc can plate and the temperature of the molten zinc, and then control the amount of residual bottom residue before the zinc pot goes online. Another is to ensure the cleanliness of the steel strip before it enters the molten zinc. Based on this, the main measures implemented are: improving the cleaning ability of the cleaning section and improving the reducing ability during annealing to inhibit the formation and accumulation of zinc powder in the furnace head area.
Study on interfacial thermal resistance between single wall carbon nanotubes and nickel by molecular dynamics
Authors: Huang Haibo , Huang Xiaohua , Meng Xianguo , Cheng Zaijun
Published: December 2022

The interfacial thermal resistance of the nanocontact system of carbon nanotubes and nickel crystals was investigated using molecular dynamics. It was found that with the increase in temperature, the interface thermal resistance gradually increased. In addition, the interfacial thermal resistance also increases gradually with the increase of the contact distance. The ballistic transport of phonons is proposed to be the main reason for the interfacial thermal resistance in this case.
Band structures of graphene, black phosphorus, and MoS2 ribbons under stress: a comparison study
Authors: Ding Rongcheng
Published: December 2022

The application of electronic devices becomes increasingly extensive and their performance optimization receives broad attention. Electronic devices constructed from two-dimensional materials have revealed broad prospects. However, the performance of two-dimensional electronic materials in the presence of stress has rarely been researched, which will restrict their application in an environment with intense deformation or temperature variation. Here, we adopt a first-principle method to investigate three kinds of ribbons: graphene, black phosphorus, and MoS2. We find that the bandgap of graphene and MoS2 ribbons increase with the rise of stress, while the bandgap of black phosphorus reduces when subject to both positive and negative stress. The abnormal trend of black phosphorus is owing to the indirect bandgap properties under negative stress, which becomes direct bandgap under positive stress. The present research has instructive meaning for the application of two-dimensional material on electronic devices under stressed conditions.
Preparation of nickel-copper layered double hydroxide on nickel foam as a non-noble catalyst for efficient electrooxidation of ammonia
Authors: Wang Haiman , Yuan Yiqing , Wang Guiqiang , Miao Zhuang
Published: December 2022

Electrochemical oxidation of ammonia is an energy-effective and environment-friendly technology for ammonia-containing wastewater treatment. The key challenge is to explore the high activity and low-price catalyst for ammonia electrooxidation. NiCu layered double hydroxide (NiCu-LDH) on nickel foam (NF) was synthesized for ammonia oxidation via a facile hydrothermal reaction. The Ni0.9Cu0.1-LDH/NF achieved a maximum current density of 78 mA·cm−2 at 1.76 V vs. RHE and a lowest Tafel slope of 195.64 MV·dec−1 in comparison with other catalysts, which was prepared by using different molar ratios of Ni2+ and Cu2+. The Ni0.9Cu0.1-LDH/NF showed smaller and denser nanosheets compared with that of Ni(OH)2/NF, indicating it had more electrochemical active areas and active sites. Chronoamperometry tests showed that the Ni0.9Cu0.1-LDH /NF reached a current density of 23 mA·cm−2 after 120 mins, which was four times as high as Ni(OH)2/NF (6 mA·cm−2). The above results demonstrated that incorporating Cu into the Ni-based layered hydroxides could improve the electrochemical activity of the catalyst, showing Ni0.9Cu0.1-LDH /NF to be a prospective inexpensive, and steady catalyst for high-performance of ammonia electrooxidation.
Research on high temperature deformation behavior and constitutive relation of TiAl alloy
Authors: Li Xiaoqiang , Fan Jiafeng , Xu Ganglai , Hou Jinbao , Wang Xuecheng , Zhu Zhencen , Shao Yonglin
Published: December 2022

TiAl alloy is a new type of superalloy with great potential in aero-engine, and its hot deformation behavior has received extensive attention. In this study, the high temperature plastic deformation behavior of TiAl alloy has been studied through compression at 900 ~1100 °C and strain rates of 0.1 s−1, 0.01 s−1, and 0.001s−1. Then, the constitutive model of TiAl alloy has been established based on the true stress-strain curve. The results show that TiAl alloy has a high sensitivity to strain rate and temperature at the experimental condition. Under the compression condition of 900 °C and 0.1 strain rate, the TiAl alloy has a penetrating crack when the strain reaches 0.6. The crack disappears as the temperature is increased and the strain rate is reduced. In addition, the plate organization in TiAl alloy breaks and spheroidizes after compression at 1100 °C,
Simulation and Study on Surface Residual Stress Influence of TC4 Titanium Alloy
Authors: Lv Chang
Published: December 2022

To study the residual stress distribution on the machining surface of TC4 titanium alloy and its influence on the milling stability, a three-dimensional milling model of TC4 titanium alloy workpiece milling with carbide end milling cutter was established based on Abaqus finite element software. Constraints were imposed according to the actual machining conditions. The distribution of residual stress on the machined surface of TC4 titanium alloy with different milling parameters was investigated by using the angular velocity and feed velocity of the tool as input load variables. The simulation results show that along the tool feed direction for reference, its residual stress was generally greater than the left side of the milling groove on the right side of the milling groove residual stress, cutting tool feed direction on the normal direction of the farther distances from the center of the tool axis of the residual stress value, the greater the residual stresses in longitudinal depth was as the smaller the farther distance milling surface stress value.
Transient simulation of slag entrapment in a tundish
Authors: Zhao Xinyu , Zhang Jianbin , Gao Feng , Wang Xianghong , Wang Litao
Published: December 2022

A transient multiphase flow model is established by solving the heterogeneous dynamic equation to simulate the process of the slag entrapment in the tundish, which can provide data for the trial production to reduce the tundish residue on the premise of ensuring no slag entrapment. A numerical simulation of critical slag entrapment height of 60 t tundish under different steel throughputs is analyzed, and the following conclusions are obtained: when the steel throughput is 3.5 t/min, 4.5 t/min, 5.5 t/min, and 6.4 t/min, the critical time of the risk of slag entrapment are 1042 s, 691 s, 561 s, and 476 s after casting end, respectively. The heights of slag entrapment are 186.9 mm, 202.9 mm, 220.5 mm, and 222.5 mm, and the heights without slag entrapment are 202.4 mm, 214.6 mm, 236.1 mm, and 238.0 mm with the throughput of 3.5 t/min, 4.5 t/min, 5.5 t/min, and 6.4 t/min.
Prediction and optimization of temperature in bone drilling based on response surface methodology
Authors: Wang Boxu , Gao Xiangsheng , Gao Peng , Liu Yunan
Published: December 2022

Bone drilling is a standard surgical procedure. High drilling temperature can reduce the biological activity of bone tissue, cause thermal damage, and possibly reduce drilling quality. This study was based on the simulation of the surgical drilling process with the finite element method (FEM). The drilling temperature was predicted through the response surface method (RSM) and obtained the minimum temperature and its corresponding drilling parameter combination. In this study, residual and variance analyses were performed on the drilling temperature prediction model and proved that the model fitting effect was good and the reliability was high. Furthermore, this study analyzed the influence trend of three parameters affecting drilling temperature: drill diameter, rotational speed, and feeding speed. It has a specific reference value for orthopedic clinical surgery.
Construction of Internet Behavior Model for Textile Industry Based on Colored Petri Nets
Authors: Wang Guodong , Liu Guohua , Ni Ping
Published: December 2022

The construction and development of the Industrial Internet provide guidelines and directions for the transformation and upgrading of the current manufacturing industry. Its main behavioral characteristic is the optimization of resource optimization, thus capturing more and more attention. Analysis of the dynamic characteristics of the Internet operation behavior of the textile industry is the key to improving the efficiency of the optimization of resource optimization. Based on colored Petri nets, we have established a behavior model for the textile industry Internet and analyzed its behavior in response to this problem. And based on the state space report of CPN Tools, the correctness of the model is verified by the branch temporal logic ASK-CTL formula and the non-standard state space query method. The accurate behavior model provides a basis for improving resource allocation efficiency in the textile industry.
Research on a mobile terminal-based control platform for the delivery and management of power material transportation
Authors: Song Binghu , Chen Jun , Zhang Yang , Chen Zhipeng , Lin Youquan
Published: December 2022

Some of the power material transportation delivery control platforms have the defect of too small throughput in the actual application scenarios, therefore, a mobile terminal-based power material transportation delivery control platform is designed. The hardware part: the mobile terminal is used to arrange the necessary equipment for operation monitoring, such as monitoring screens and servers, and is connected to the industrial control mainframe through a USB connection cable and to GPS devices; the software part is on the basis of the established reserve strategy, the process of power material transport delivery control is improved, the number of profitable stored within the cross item is calculated for each demand entry and the corresponding inventory entry, and the balance profitability constraints are extracted, isolating the base stations and optimizing the system’s intelligent inventory function. Test results: The power material transport delivery control platform in the paper has a higher average throughput than the other two power material transport delivery control platforms: 26.344req/s and 24.495req/s respectively, indicating a higher practical value of the designed power material transport delivery control platform after making full use of mobile terminals.
Improvement of SIFT algorithm and its application in visual inspection system for PET bottle capping defects
Authors: Li Dan , Yang Mengqin
Published: December 2022

Aiming at the defects of PET beverage bottles in the process of capping and filling, an improved algorithm based on visual inspection is proposed. First, an improved SIFT algorithm is proposed to improve the running speed, and OPENCV, C++, and Virtual Studio are used to build the interface and implement the algorithm. The preprocessed images are analyzed by the improved SIFT algorithm, and experiments and data analysis are carried out. The research results show that compared with the traditional SIFT algorithm, the improved SIFT algorithm greatly saves the algorithm time when detecting PET bottle capping defects and retains the anti-interference ability of SIFT feature points. The detection of insufficient liquid levels provides a new method and makes the algorithm more practical and valuable.
Knowledge Modelling for the Smart Design of Aluminium Profile Extrusion Dies
Authors: Qin Hao
Published: December 2022

Aluminium profiles are widely used in distinct fields since their excellent physical properties, and the quality and efficiency of producing aluminium profiles are largely depending on the extrusion dies. Therefore, the design of the aluminium extrusion die is the most significant part. However, the extrusion die design is a complex process, which includes plenty of data, information, and knowledge. In production, reusing part of the previous design information and knowledge can improve design efficiency. In this case, this study has explored the way to systematically model the design knowledge generated during the aluminium extrusion die design process. Firstly, knowledge representation models have been created, acting as the schema layer of the domain knowledge graph for the aluminium extrusion die design. This knowledge graph is subsequently used as the repository of a Web-based smart design system. By providing the three key functionalities of knowledge representation, semantic retrieval and intelligent recommendation, the smart design system can help engineers effectively reuse previous design knowledge to improve design efficiency and quality.
Design of Inductive Power Taking System for Smart Grid Monitoring Equipment
Authors: Yang Mengqin , Li Dan , Yang Jun
Published: December 2022

Due to the continuous growth of urban electricity load and the increasing development of high-voltage transmission technology, the effective operation of the online monitoring equipment of the transmission line is particularly important, which is also a necessary condition for the development of the smart grid. However, the power supply conditions for the usage scenarios of smart grid monitoring equipment are limited. Conventional power supply methods such as battery power supply and new energy power generation have disadvantages such as cumbersome battery replacement, and the power supply stability is greatly affected by the environment, so they are difficult to meet the development trend of a rapid capacity increase of power grid and stable power supply of power equipment. Aiming at the technical bottleneck of smart grid monitoring equipment in power supply, this paper proposes a current transformer inductive power taking method based on capacitive reactance matching shunt, using the open air gap current transformer secondary winding set on the bus to connect the capacitor and its excitation inductance in series carry out capacitive impedance matching, and then shunt through another branch with load and connect it at both ends of the open air-gap current transformer to obtain electric energy. Through the circuit model experiment of the inductive power-taking system, it is verified that the current transformer inductive power-taking method based on capacitive reactance matching shunt can obtain more power.
Investigation on microstructure evolution and corrosion resistance of CeO2 particle reforcemented Aluminum matrix composites by powder metallurgy
Authors: Zhao Yinji , Bao Lei , Le Qichi
Published: December 2022

Aluminum matrix composites reinforced by cerium oxide particles with different contents (0, 5%, 10%, 15% and 20%) were prepared by powder metallurgy. The morphology and structure of the composites were characterized by X-ray diffraction and scanning electron microscope. The corrosion behavior of CeO2 particle reinforced aluminum matrix composites with different content in 3.5% NaCl solution was tested by Tafel polarization curve. The results show that CeO2 is evenly distributed in the matrix, and the addition of CeO2 can effectively reduce the corrosion rate and improve the corrosion performance.
Three-dimensional Conductive Interconnected Graphene Networks for High-Performance Electromagnetic Interference Shielding
Authors: Ma Yanhao , Ai Ding , Yu Hao , Dong Chengye , Sun Nuoling , Cheng Yonghong
Published: December 2022

As electronic and information technology advance, it is critical to reduce the electromagnetic pollution caused by electronic devices. Herein, graphene foam (GF) was prepared via chemical vapor deposition and composited with polydimethylsiloxane (PDMS) to prepare GF/PDMS composites with excellent flexibility. It was discovered that the GF/PDMS composites morphologically coupled to each other to create a low-density porous network with excellent electrical conductivity. A comprehensive investigation of the relationship between electromagnetic interference (EMI) shielding performance and 3D graphene foam growth conditions indicated that the thickness of graphene, influencing the continuity and conductivity of 3D foam, has a critical influence in how well GF/PDMS composites perform in terms of EMI. Furthermore, the electromagnetic shielding effectiveness and absolute effectiveness of the GF/PDMS composites in our work can be higher than 52 dB and 2800 dB·cm2/g, respectively, which is better than most carbon-based EMI shielding materials. The comprehensive studies on GF/PDMS composites in this work will benefit the application of electromagnetic shielding materials for next-generation aviation and wearable devices.
Computer simulation prediction of uranyl ion capture by hetero-sulfide perhydroxycalix[4]arene
Authors: Wang Liying , Li Jianhuang , He Ying , Yu Yao , Wu Yuzhu , Liu Yu , Guo Wenlu , Lan Wenbo
Published: December 2022

In order to explore the effect of calix[4]arene hetero-sulfidation on the capture ability of uranyl ions, computer simulations were used to predict that the B3LYP method in density functional theory, the perhydroxycalix[4]arene with different numbers of hetero-sulfur atoms effects on uranyl ion capture ability, and the compounds formed. We gradually replaced the methylene group "-CH2” in the perhydroxycalix[4]arene with "-S-", and combined the substituted perhydroxycalix[4]arene and the uranyl ion to form a complex. Structural optimization was carried out to further verify that the complexes can exist stably after structural optimization. The structural features of the optimized complexes were analyzed, and the molecules of infrared spectroscopy, the binding energy of calix[4]arene to uranyl ion after hybridization S, and the frontier molecular orbital energy levels of the complexes formed were studied. The number of calixarene-hetero-S with the strongest ability to capture uranyl ions and the number of calixarene-hetero-S with the best chemical stability of the complex formed after the capture of uranyl ions were found.
Natural Superhydrophobic Surfaces and Application
Authors: Wang Zhuoqin , Kong Jianan , Zhou Qixiang , Chen Xinjia
Published: December 2022

Superhydrophobicity refers to the phenomenon that the contact angle of various low surface tension water droplets on the solid surface is greater than 150°. Over the past few years, people have paid more attentions in the superhydrophobic surfaces’ design and application. The superhydrophobic surfaces are meaningful for basic research and various practical applications, such as self-cleaning, drag reduction, lubrication, and more. This paper summarizes the recent advances and developments in superhydrophobic surfaces systematically. Furthermore, in this work, the authors focus on the basic concepts of superhydrophobic surfaces and commonly used synthetic methods. Electrodeposition and electrospinning methods are mainly introduced. Finally, we also discuss the limitations and challenges encountered in the study of superhydrophobicity, mainly with regard to the fact that drag should be reduced to improve energy harvesting efficiency.