bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dimethylamine Exchanging of a New Hole Transport Material for Highly efficient CsPbI2Br solar cells
Authors: Wang Ze , Gan Jiantuo , Liu Xiaodong , Shao Ming , Bie Tong , Qiao Liang , Zheng Yonghao 
Published: January 2022

Abstract
All inorganic α-CsPbI2Br films with a large open circuit voltage (V
OC) and excellent thermal stability are promising for highly stable and efficient perovskite solar cells (PSCs). However, its device performance is limited by a low short circuit current density (J
SC) and low V
OC, which is strongly related to the energy misalignment and defects recombination at the perovskite/transport layer interfaces. In this work, we develop two Ni based polymers: bis (dithiobenzil) nickel (II) (BDTB) and bis(4-dimethylaminodithiobenzil) nickel (II) (BDMA), and use them as the hole transport layer for α-CsPbI2Br PSCs. As compared to BDTB based reference device (PCE ~3.2%), BDMA based device demonstrate a simultaneous increase on V
OC, J
SC and fill factor (FF), resulting in a remarkable power conversion efficiency (PCE) of 13.32 %. We attribute the improved device performance to a better interfacial alignment, the reduced defect recombination and improved charge extraction. Moreover, the BDMA based devices also exhibit an improved shelf-life stability than BDTB control device, which sustain over 80 % of PCE after 50 days in ambient air.
The friction and Wear behavior of Silicon oil-based Magnetorheological fluid with Solid lubricant
Authors: Hu Zhide , Zhang Hansong , Zhao Hujun , Wang Dawei 
Published: January 2022

Abstract
Due to its lower energy consumption, higher mechanical properties and easier to control, magnetorheological(MR) fluid has been widely used in the engineering field. However, the friction and wear behavior of it, which may hinder its applicability, needs to be modified. The tribological behavior of silicon oil-based MR fluid with different types and contents of solid lubricant was investigated on a four-ball machine. The worn surfaces of the steel balls were observed by using a scanning electron microscope (SEM). The results showed that the friction and wear property of silicon oil-based MR fluid could be improved by some solid lubricants. Both of molybdenum disulfide and graphite can decrease friction coefficient of silicon oil-based MR fluid significantly, but graphite has the better wear resistance than molybdenum disulfide. Adding polytetrafluoroethylene (PTFE) can enhance the wear resistance of MR fluid obviously, but the friction coefficient is larger than the first two. The friction and wear property of MR fluid hardly changes by adding boron nitride. Increasing the content of graphite can improve the friction and wear resistance of MR fluid, and the wear resistance of MR fluid has an optimal point when the weight percent of graphite is 2%.
Study on heat dissipation structure of air-cooled Lithium ion battery module
Authors: Wang Jingyu , Qin Dongchen , Wang Tingting 
Published: January 2022

Abstract
The battery cooling system is an important part of the battery thermal management system. Its main function is that when the battery temperature is too high, it can carry out effective heat dissipation to reduce the battery surface temperature, and reduce the temperature difference to ensure the stability of the battery temperature field. In this paper, a simplified model of air - cooled lithium - ion battery module is established, and based on computational fluid dynamics (CFD) theory, Fluent software was used to simulate the temperature field and flow field of the battery module in different inlet directions. The influence of the distance between the battery and the air inlet wind speed on heat dissipation was simulated. Under the condition of comprehensive consideration of the battery volume energy density and heat dissipation energy consumption, the final result is that the heat dissipation structure of the air-cooled battery module reaches the optimal when the lateral ventilation is used, the battery spacing is 5 mm, and the wind speed is set at 4 m/s.
Application of Color Metallography on As-cast Al-Mg-Si-Cu-Mn Alloy during Heat Treatment
Authors: Wang Xiaoguo , Qin Jian , Liu Fangzhen , Li Yifeng , Nagaumi Hiromi 
Published: January 2022

Abstract
Color etching was performed to characterize microstructure evolution and phase transformation on as-cast and homogenized Al-Mg-Si-Cu-Mn alloys. Initial intermetallic phases in microstructure of as-cast Al-Mg-Si-Cu-Mn alloy are mainly composed of primary Mg2Si, α-Al(FeMn)Si and quaternary Q phase. Post-etching microstructure of as-cast alloy presents a typical dendritic morphology with distinctive intermetallic distributions. Micro-segregation of solute elements are visualized as color difference within grains. Q phase is mainly located between the dendrite arms, while Mg2Si and α-Al(FeMn)Si are arranged along the grain boundaries. Heterogeneous nucleation sites provided by Al3Ti during solidification are also observed and identified at the core of grains. The distribution of alloying elements and intermetallic exhibited by color micrograph presents a good agreement with outcomes of EPMA. The color metallography of etched sample reveals the distribution of α-Al(MnCr)Si dispersoids and dispersoids free zone (DFZ), after the alloy is subjected to two-step homogenization. Micro-segregation of solute elements within solid solution is dramatically eliminated, associated with reduction of color difference. The dissolution of primary Mg2Si and Q phase during two-step homogenization are also directly detected. Therefore, color etching is an effective and reliable auxiliary approach to reveal microstructural evolution and phase transformation of as-cast Al-Mg-Si-Cu-Mn alloy during homogenization process.
Effect of Pulse Frequency on Phase Composition and Properties of Amorphous Zirconium Alloy Micro-arc Oxidation Coating
Authors: Li Chunjiang , Mu Liting , Zhuang Minghui , Li Muqin , Ma Zhen 
Published: January 2022

Abstract
The micro-arc oxidation coating was prepared on the surface of the amorphous zirconium sheet, and the influence of frequency on the micro-arc oxidation coating of the Zr-based amorphous alloy was studied. The results show that the change of the frequency of the electrical parameters of the micro-arc oxidation in the silicate micro-arc oxidation bath will promote the transformation of the t-ZrO2 phase to the m-ZrO2 phase in the coating; the frequency affects the gap, uniformity and thickness of the coating. When the frequency is 400 Hz, the coating surface has small voids and no cracks, and the thickness reaches a maximum of 15 μm. With the increase of frequency, the weight loss of the amorphous zirconium micro-arc oxidation coating first decreases and then increases. The wear resistance can be improved.
Research on Hydrogen Fuel Cell Safety Detection Analysis Based on Leakage Quality Limit Detection Method
Authors: Liu Mengmeng , Zhang Shupeng 
Published: January 2022

Abstract
As the state has increased its support for hydrogen fuel cell electric vehicles, many domestic companies and scientific research institutions have carried out the research and development of fuel cell vehicles, and many models have also received national announcements. However, due to the lack of standards related to the hydrogen safety detection of fuel cell electric vehicles after collision in the current international standard systems, various companies formulate their own testing plans and technical requirements when conducting collision tests, and there are standards inconsistencies. After comparative analysis of foreign standards on the hydrogen safety detection methods and requirements of fuel cell electric vehicles after collision, relevant suggestions are given to the collision plan, which provides a reference for the domestic development of fuel cell vehicle collision research.
Rapid fabrication of near superhydrophobic aluminium surface through nanosecond laser texture and heat treatment
Authors: Fan Changfeng , Wang Xue , Liu Yancong , Li Chengkai , Liu Xiao 
Published: January 2022

Abstract
Controlling surface wettability inspired by nano structure of lotus leaf has attracted much attention. The superhydrophobicity on the metals is significant for the applications including water repellence, self-cleaning, anti-corrosion, and reduction of drag. Herein a near superhydrophobic surface of 5051 aluminium has been fabricated by employing a combination of nanosecond laser texture and heat treatment, without using any toxic chemicals. The aluminium surface was textured by fibre nanosecond laser and then heat treated at 150 °C to create the near superhydrophobic surface. The evolution of heat treatment time with respect to contact angle measurements has been investigated. The contact angle became 0° when processed by two different kinds of laser textures (sinusoid pattern and grid pattern). The influence of heat treatment on the wettability of the laser textured aluminium surface was studied. The contact angle exhibits 134.88° and 136.97° for sinusoidal pattern and grid pattern with 72 hours heat treatment, respectively. The mechanism for fast wettability conversion time is discussed. This method is a rapid and environment-friendly process, which is feasible for fabrication.
Research on forming effect of material with different thickness structure in continuous flexible rolling process
Authors: Liu Shulin , Li Yi 
Published: January 2022

Abstract
Continuous flexible rolling is a novel advanced manufacturing technology for vehicle body surface, the forming mechanism of this process is based on the uneven thickness reduction of rolled plate along the transversal direction. In the rolling forming process, working hardening is always an important factor for affecting thickness reduction of rolled plate. In this work, the method of decreasing working hardening was studied deeply in continuous flexible rolling process for 3D surface. By finite element analysis, the forming effect of metal plate with different thickness structure was studied in continuous flexible rolling process. The rolled plate consists of three piece of metal plate; in the comparing experiments, the total thickness of rolled plate is 3mm, from compression surface to tension surface, the thickness ratio of each layer metal plate is 1:1:1, 1:2:2, 2:1:2, 2:2:1 in order. The results show that: with the location of the thinnest metal plate moves down, plastic strain in the middle surface of rolled plate is increasing greatly, the thickness reduction is also improving significantly, and the thickness distribution is almost unchanged. Therefore, to optimize rationally the thickness structure is an effective method to decreasing working hardening, the forming precision of 3D surface can get improving in continuous flexible rolling process.
Research on the Performance of Brass Alloy Main transformer terminal
Authors: Liu Weike , Yi Yijie , Cao Xianhui , Xi Chongyu , Wang Zhensheng , Xie Yi , Feng Chao 
Published: January 2022

Abstract
In order to determine the material of the main transformer terminal, the electrical conductivity, mechanical properties and stress corrosion resistance of brass alloy terminal were studied by XRD, mechanical properties test and ammonia fumigation test. The results show that H59 alloy consists of (Cu, Zn) phase, Cu5Zn8 phase and CuZn phase, H70 alloy consists of (Cu, Zn) phase and dendritic Cu0.64Zn0.36 phase, H80 alloy and H90 alloy are both (Cu, Zn) phase. With the increase of Cu content, the strength of brass decreases, the conductivity increases, and the stress corrosion resistance increases. H90 alloy has excellent plasticity and toughness, excellent resistance to ammonia fumigation stress corrosion, and can be used as main transformer terminal material.
Influence of Early Strength Agent on the Strength and Water Resistance of Cement-Desulfurized Building Gypsum Composite Cementitious System
Authors: Peng Hong , Lv Zhong , Zhang Wenwei 
Published: January 2022

Abstract
The test takes the cementing system composed of ordinary Portland cement and desulfurized building gypsum as the research object, and the research is carried out based on the mechanism of the early strength agent that can accelerate the cement hydration reaction in the composite cementing system. In the experiment, the influence of the type and dosage of the early strength agent on the strength and water resistance of the composite gelling system was studied to determine the appropriate type and optimal dosage of the early strength agent. The test results show that sodium sulfate has a poor improvement effect on the sample due to the presence of desulfurized building gypsum in the composite cementing system, while calcium chloride and calcium formate can effectively promote the hydration of the cement in the composite cementing system, significantly improving the compressive strength and softening coefficient of the sample. When the calcium chloride content is 2%, the compressive strength of the sample is increased by 57.0% compared with the reference sample, and the softening coefficient is 0.82. When the calcium formate content is 1%, the compressive strength of the sample is increased by 31.1% compared with the reference sample, and the softening coefficient is 0.80.
Research on Jet Incoherence of Depleted Uranium Liner
Authors: Tang Hui , Jiao Zhigang , Zhao Lijun , Zhao Dongzhi , Tian Zhen , Wang Changfu 
Published: January 2022

Abstract
Jet formation is the decisive factor of penetrating power of shaped charge, coherence and stability contribute to penetration. In the same condition, multiple penetrating tests of the shaped charge with depleted uranium(DU) liner did not get the expected results. In order to study the jet forming characteristics of DU liner under static explosion condition, an X-ray photography experiment was designed, which turned out to show the jet being badly incoherent. To research the incoherence of DU shaped charge jet from principles of jet incoherence, supersonic collision worked out to be the reasons for incoherence of the shaped charge jet. This paper provides a method for structural optimization of DU shaped charge and DU liner processing, which has guiding significance for application of DU liner in high explosive antitank projectile.
Double machine vibration synchronization system based on GA-PID
Authors: Jia Yijun , Zhang Nan , An Zhaozhe 
Published: January 2022

Abstract
Aiming at the problem that it is difficult to realize the synchronization of motor speed under the electromechanical coupling condition of DC motor and vibrating mass in double machine drive vibration system, the PID parameters of DC motor are optimized by using master-slave control mode and genetic algorithm. Firstly, the electromechanical coupling model of the vibration system is established, and the differential equation of motion of the system is obtained by using Lagrange equation; Using master-slave control structure and genetic PID control algorithm, a controller based on master motor speed difference and slave motor phase difference is designed; The MATLAB/Simulink simulation model is established to verify the effectiveness of the control system. The experimental results show that the genetic PID algorithm based on master-slave control structure can better realize the synchronous control of dual machine driven vibration system. The research content can provide a theoretical basis for the design, control and application of this type of vibration system.
Self-Synchronization Theory of Circular Symmetrical Four Motors
Authors: Jia Yijun , Zhang Nan , An Zhaozhe 
Published: January 2022

Abstract
The synchronization characteristics of the circularly symmetrical four-vibrators vibration system are studied. Firstly, the dynamic model of this type of vibration system is established, and the Lagrange equation is used to derive the differential equation of motion. Secondly, the steady-state solution of the vibration system is obtained by averaging the phase of the eccentric rotor of the four exciters in the vibration system, and Hami is used. The frame principle deduces the synchronization conditions and stability conditions for the four vibration exciters of this type of vibration system to achieve synchronous motion. Finally, the correctness of the theoretical analysis is verified by numerical simulation. The relevant research results can provide a theoretical basis for the design of the circularly symmetrical four-vibrators vibration machine.
Research on trajectory correction model of dual magnetic navigation differential mobile robot
Authors: Zhang Baixing , Sun Xuan , Liu Minghao , Lin Zifei , Cao Jinshun 
Published: January 2022

Abstract
In order to improve the pose accuracy of magnetic navigation mobile robot, differential driving mobile robot is taken as the research object. The kinematics and deviation model are analyzed by means of double magnetic strip sensor navigation. The kinematic model is built in SIMULINK, and a fuzzy controller with double input and single output is designed through MATLAB, and the motion process is simulated and analyzed. The feasibility of the kinematic model is verified and the fuzzy rectifying controller designed in this paper has good rectifying control performance and response characteristics.
Water Source Heat Pump’s Stuck Problems and Solutions
Authors: Guo Liyu , Shan Wenju 
Published: January 2022

Abstract
This paper analyses the water source heat pump’s normal stuck reasons, and test each of them. Identify the main reasons of the stuck pump is pump mechanical seal dynamic ring and static ring binding problems. (Poor water quality, water calcium carbonate, magnesium carbonate grind through the dynamic and static ring, after a long time stop, static ring long force extrusion contact, static ring binding surface molecular diffusion migration adhesion), due to the two rings’ binding, rotating torque beyond the motor starting torque, make the motor can’t start normally. This paper aims to find the real cause of the dynamic ring absorption, and put forward subsequent rectification measures to prevent recurrent stuck.
Tunable Thermal Pattern for Thermal Illusion and Encrypted Messaging
Authors: Qiu Rihong 
Published: January 2022

Abstract
Recently, metamaterials which can actively tuning heat flux has attracted a lot of researchers and these thermal functional materials can be used in many thermal application scenarios such as encrypted messaging and thermal illusion. In this paper, the bilayer structure array with a chessboard-like structure has been proposed and we have numerically acquired a tunable thermal pattern based on effective medium theory. Through this strategy, a thermal pattern which is almost the same with the patterns of ‘ECE’ can be obtained. After quickly tuning this 3*12 array of the 4*4 chessboard-like bilayer structure, another thermal pattern which looks like the patterns of ‘SOS’ is observed in the infrared camera instead, demonstrating the feasibility of thermal illusion. Furthermore, the functionality of encrypted thermal messaging is also numerically demonstrated by resorting to storing the analog patterns of the binary numbers. Besides, this kind of tunable bilayer array is quite simple and flexible, and it can also serve as thermal metamaterial when the corresponding matching function is satisfied. In all, this present bilayer structure array with a chessboard-like structure can obtain tunable thermal patterns without disassembly of any components and it might open more strategies for creating novel thermal functionalities.
Nonlinear Creep Model and Parameter Determination of Asphalt
Authors: Fan Xiyan , Jiang Wenling , Mei Ning , Su Chuanqi 
Published: January 2022

Abstract
Asphalt is a kind of typical viscoelastic material. Adding different materials in asphalt composite materials is an important way in road engineering materials. The creep experiments under different stress of asphalt, we used the multivariate model to fit the experimental data to get Burgers model and the creep law of asphalt correlation is best. The Burgers model be expanded by Taylor series, the polynomial creep model of creep compliance and relaxation characterized the coefficient of asphalt specimen can be obtained. Compared to other models, the creep law of asphalts well characterized by polynomial model, multivariate model has a wider range of adaptability compared to polynomial model, and polynomial model of mathematical calculation more simple than multivariate model.
Rheological characteristics analysis of shear thickening fluids based on response surface methodology
Authors: Zhao Mingmei , Zhang Jinqiu , Liu Yile , Peng Zhizhao , Li Xin 
Published: January 2022

Abstract
This paper analyzed the influence of various components and the external environment on the rheological properties of shear thickening fluid (STF). The single-factor experimental study was carried out with the silica particle size, the mass fraction of silica particles, the continuous phase’s average molecular weight, and the temperature as the influencing factors. Obtain the influence of various factors on the initial viscosity, critical shear rate, thickening period and thickening ratio of STF samples. According to the crossover relationship between the shear stress and the intermolecular force when the shear thickening occurs, the STF’s critical shear rate criterion is constructed. By introducing the mechanical balance between small molecules, the relationship between the particles’ volume fraction and the distance between particles in the suspension system is established. The influencing factors and formulas of the STF’s critical shear rate and shear capacity are deduced, which supports the conclusions obtained in the single-factor experiment. Based on the single-factor experiment conclusion, the mass fraction of silica particles, the average molecular weight of the continuous phase and the temperature are used as the influencing factors, and the critical shear rate, shear thickening ratio and maximum viscosity are the responses indicators. According to the Box-Behnken response surface methodology (RSM) design, 15 analysis experiments with three factors and three levels are carried out. Obtain the rheological characteristics of the STF and regression equation between each factor, based on the three-dimensional response surface graph and F-value in ANOVA result. We found that among the interaction effects, the interaction between the continuous phase’s average molecular weight and the temperature has the most significant impact on the critical shear rate of the STF. The interaction between the silica particles’ mass fraction and the continuous phase’s average molecular weight significantly impacts the shear thickening ratio of the STF. The interaction between silica particles’ mass fraction and the temperature has the most significant impact on the maximum viscosity of the STF. Finally, according to the response surface methodology experimental results and ideal STF rheological characteristics standard in engineering applications, when the mass fraction of silica particles is 35%, the average molecular weight of the continuous phase is 387, and the temperature is 20 °C. The critical shear rate of the STF system is 5.84 1/s, the shear thickening ratio is 102.8, and the peak viscosity is 1191.7 Pa·s, reaching the optimal theoretical value within the value scope.