bluuebunny/crossref_metadata_2025 huggingface dataset:
Rugby league ball carrier injuries: The relative importance of tackle characteristics during the European Super League
Authors: Hopkinson M. , Nicholson G. , Weaving D. , Hendricks S. , Fitzpatrick A. , Naylor A. , Robertson C. , Beggs C. , Jones B.
Published: November 2020

Rugby league carries a high injury incidence with 61% of injuries occurring at tackles. The ball carrier has a higher injury incidence than the defender, therefore understanding mechanisms occurring during injurious tackles are important. Given the dynamic, open nature of tackling, characteristics influencing tackle outcome likely encompass complex networks of dependencies. This study aims to identify important classifying characteristics of the tackle related to ball carrier injurious and non‐injurious events in rugby league and identify the characteristics capability to correctly classify those events. Forty‐one ball carrier injuries were identified and 205 matched non‐injurious tackles were identified as controls. Each case and control were analysed retrospectively through video analysis. Random forest models were built to (1) filter tackle characteristics possessing relative importance for classifying tackles resulting in injurious/non‐injurious outcomes and (2) determine sensitivity and specificity of tackle characteristics to classify injurious and non‐injurious events. Six characteristics were identified to possess relative importance to classify injurious tackles. This included ‘tackler twisted ball carrier's legs when legs were planted on ground’, ‘the tackler and ball carrier collide heads’, ‘the tackler used body weight to tackle ball carrier’, ‘the tackler has obvious control of the ball carrier’ ‘the tackler was approaching tackle sub‐maximally’ and ‘tackler's arms were below shoulder level, elbows were flexed’. The study identified tackle characteristics that can be modified in attempt to reduce injury. Additional injury data are needed to establish relationship networks of characteristics and analyse specific injuries. Sensitivity and specificity results of the random forest were 0.995 and 0.525.
Large transient capacitive currents in wild-type lysosomal Cl−/H+ antiporter ClC-7 and residual transport activity in the proton glutamate mutant E312A
Authors: Pusch Michael , Zifarelli Giovanni
Published: November 2020

ClC-7 is a lysosomal 2 Cl−/1 H+ antiporter of the CLC protein family, which comprises Cl− channels and other Cl−/H+ antiporters. Mutations in ClC-7 and its associated β subunit Ostm1 lead to osteopetrosis and lysosomal storage disease in humans and mice. Previous studies on other mammalian CLC transporters showed that mutations of a conserved, intracellularly located glutamate residue, the so-called proton glutamate, abolish steady-state transport activity but increase transient capacitive currents associated with partial reactions of the transport cycle. In contrast, we observed large, transient capacitive currents for the wild-type ClC-7, which depend on external pH and internal, but not external, Cl−. Very similar transient currents were observed for the E312A mutant of the proton glutamate. Interestingly, and unlike in other mammalian CLC transporters investigated so far, the E312A mutation strongly reduces, but does not abolish, stationary transport currents, potentially explaining the intermediate phenotype observed in the E312A mouse line.
Seeding self-modulation of a long proton bunch with a short electron bunch
Authors: Muggli P. , Guzman P. I. Morales , Bachmann A.-M. , Hüther M. , Moreira M. , Turner M. , Vieira J.
Published: November 2020

We briefly compare in numerical simulations the relativistic ionization front and electron bunch seeding of the self-modulation of a relativistic proton bunch in plasma. When parameters are such that initial wakefields are equal with the two seeding methods, the evolution of the maximum longitudinal wakefields along the plasma is similar. We also propose a possible seeding/injection scheme using a single plasma that we will study in upcoming simulations works.
Analysis on Self-healing Properties of Membrane
Authors: Wang Shixi
Published: November 2020

Due to special compositions and structures, polymer membrane materials usually show a variety of excellent functions. However, the hardness of polymer materials are much lower than inorganic materials, so they are easy to suffer external damage in the process of use. The damaged polymer material will lose its original function and become unable to continue to use, which will have a serious impact on our production and life. Therefore, it is one of the most effective methods to extend the service life and improve the functional reliability of polymer functional materials to endue them with self-healing properties. In this paper, the principle, classification and research results of self-healing membrane are introduced. In particular, this paper explores the application of microcapsule self-healing technology in membrane field, conclude the influence of various components of microcapsule self-healing technology on membrane properties, and discuss the self-healing technology of cellulose membrane and polyethersulfone membrane. In addition, the author also pointed out the development direction of self-healing technique in membrane field.
Study on the Cutting Surface Formation Mechanism of TA2 and TC4
Authors: Nie Cong , Liu Gui-Zhong
Published: November 2020

High speed machining of titanium and titanium alloy is an important and fundamental research topic in the field of machining. In this paper, the cutting experiments of commercial pure titanium TA2 and titanium alloy TC4 were carried out at different speeds. We used roughness measuring instrument and scanning electron microscope (SEM) to observe and analyze the cutting surface and particularly analyzed its roughness and microstructure characteristics under different cutting speeds. The experimental results show that in the cutting process, when the cutting speed of TA2 is higher than 79.13m/min, the surface roughness is reduced, the influence depth of extrusion and dislocation becomes shallow, and good surface quality is obtained; when the cutting speed of TC4 is close to 79.13m/min, the surface roughness is reduced, the influence depth of extrusion and dislocation becomes shallow, and good surface quality is obtained. At the same cutting speed, the surface roughness of TC4 is less than TA2, and the influence depth is also less than TA2, so Titanium alloy TC4 is easier to get good surface quality.
The Dripping Behaviors of PE Metal Sandwich Panel Insulation material at Different Powers
Authors: Fan Yinke , Zhou Ru
Published: November 2020

An experimental study on the characteristics of molten drop and flame spread of metal polyethylene (PE) cladding panel is presented. The parameters investigated include mass loss rate, the mass of the melting part and the average flame height. The effects of fire source power on the flame spread and melt drop are studied. The results show that the sandwich panel combustion can be divided into the surface of the sandwich panel and the dripping combustion. With the increase of power,the time interval between melting drops becomes smaller and the flame pulsation frequency increases. which causes the temperature change range getting larger, the mass loss rate and mass of the melting part and the average flame height increase under all conditions. The mass loss rate and the area of combustion of the metal sandwich panel depend on the degree of surface burning. There is a certain relationship between oil pool fire average flame height, and the distance between sample and the oil pan(D). It is found that when D ≤ 1.4m, with the rise of D. oil pool fire average flame height decreases. However, when D ≥ 1.4m, the fire flame intensity of the oil pool is determined by the number of extinguished droplets before the drops hit the oil pan, and the flame parameters of the oil pool are basically stable. The influence mechanism and law of oil pool fire burning of PE metal sandwich panel insulation materials are revealed.
Effect of nitrate nitrogen content on properties of modified single-base propellant
Authors: Zhang Haotian , Xu Bin , Liu Zhitao , Liao Xin
Published: November 2020

In order to investigate the effect of nitrocellulose (NC) nitrogen on the performance of modified single-base propellants, modified single base propellants with different nitrogen content (12.8%, 12.7%, 12.6%, 12.4%) were prepared by solvent extrusion. The mechanical properties of the modified single-base propellant were tested using a universal material testing machine and a simply supported beam impact tester; the impact section was observed by a scanning electron microscope; and the combustion performance of the modified single-base propellant was tested by a closed explosive device test. The results showed that the higher the nitrogen content of nitrocellulose, the worse the swelling effect, the worse the cotton’s dissolving ability, and the worse the mechanical properties of modified single-base propellant; as the nitrogen content increases, the burning rate and force capacity of the propellant gradually increase.
Lightweight Design of Vertical Lathe Bed for Repairing Wheel based on ANSYS Workbench
Authors: Zhang Qingping , Zhang Jianhua
Published: November 2020

The casting bed of vertical lathe for repairing wheel hub is optimized to realize the lightweight design. The optimal selection scheme is optimized to improve the first natural frequency and reduce weight. Multi-objective genetic algorithm is based on the general algorithm of genetic algorithm to solve the problem. The five important dimensions of the bed structure are multi-objective optimized to determine the best optimization scheme. According to the results of multi-objective optimization design of bed, the optimal design scheme based on objective optimization is obtained. After the parameters are rounded, the casting bed is brought into the whole machine model, and the static analysis of the whole machine is carried out to check the safety of the structure.
High-temperature Ceramic Manganese Crystal Glaze
Authors: Shen Haiyong , Yang Jingyu , Li Jun
Published: November 2020

The main purpose of this paper was to produce high-temperature ceramic manganese crystal glaze made from manganese dioxide by firing at 1310 ° C in reducing flame atmosphere. This paper describes the process of glaze preparation and the kiln temperature controlling during the glaze firing process in detail. For the glaze effect of the manganese crystalline glaze after firing, the super-depth-of-field three-dimensional microscope is used to observe the true depth of field of more than 20 times of the optical microscopic system.
Effect of Milling Parameter on the Surface State of Ultra-high strength Steel 16Co14Ni10Cr2Mo
Authors: Xu Jin , Yan Fuwu , Li Yan , Yang Zhenchao
Published: November 2020

The machining mechanism and process parameters of ultra-high strength steel 16Co14Ni10Cr2Mo are still lack of complete understanding. By changing the milling condition, the influence of process parameters on cutting force, such as Radial milling depth, Axial milling depth, Feed per tooth and milling speed, is studied,and in the meanwhile that the surface morphology and hardness of 16Co14Ni10Cr2Mo after machining are analyzed. Indicating that the milling force increases with the increase of axial milling depth, feed rate and radial milling depth. With the increase of milling speed, the milling force reduces. The effect of axial cutting depth and radial cutting depth on cutting force is maximum. For 16Co14Ni10Cr2Mo ultra-high strength steel, it is suitable to use small cutting depth and high milling speed. On the surface of milling material, partial melting and partial oxidation of chips occur. When the milling speed and feed rate increased, the surface hardness of the material did not change significantly, and there was no work hardening.
Hot Compression Deformation Characteristics of Nimonic Alloy as-forged
Authors: Chunchun WU , Keyu JIN , Gang CHEN
Published: November 2020

Hot Deformation Behavior and Constitutive Model of the nickel-base alloy Nimonic Alloy as–forged are investigated by hot compression tests in the ranges of strain rate (0.001-1s−1) and temperature 1323-1423K, at intervals 50K. During the process of compression deformation, with the increase of true strain, the flow stress first increases rapidly to the peak value. Then, the flow stress decreases with the increase of true strain. Flow curves show dynamic recrystallization occurs at low strain rate (0.001-0.1 s−1) and temperature (1323-1423K). The softening mechanism at high strain rate (1 s−1) is dynamic recovery. According to the values of the ture stress and strain, the material constants of constitutive model are calculated and Arrhenius-type equation is given.
Research on the Influence of Main Spinning Process Parameters on the Forming Quality of 20 Steel by Strong Spinning
Authors: Yang Yu
Published: November 2020

With the continuous development of spinning technology, more and more products are processed by spinning. Every time spinning a new product, it is necessary to reset the spinning process parameters, which are usually determined by spinning process test. If the influence of spinning process parameters on the forming quality can be grasped, it can help the rapid setting and optimization of spinning schemes. In this paper, through a large number of spinning process tests, the effects of spindle speed and feed rate on the strength of 20 steel were analyzed, including the defects such as corrugation, cracking, and diameter expansion, as well as the spinning force, roundness and nominal diameter tolerance. The research results of this paper have certain scientific significance for the reasonable setting of process parameters of 20 steel, and provide theoretical basis for the optimization of spinning process parameters.
Experiment of ice ball impacting glass fiber laminate
Authors: Liu Yang , Qu Jia , Ju Dianwei , Pang Yuezhao , Yan Xiaojun
Published: November 2020

As a solid form of water, ice has brought a lot of technical challenges to aviation, ships, bridges and other related engineering fields, the technical fields such as the impact protection strength of aircraft and the strength design of icebreakers need to consider the influences of ice impact on structural strength and reliability. Therefore, in order to solve such problems, this paper takes the hail disaster as the background, and applies a first-level air gun to use 50.8mm (2inch) and 25.4mm (1inch) diameter ice balls to conduct impact experiments on glass fiber laminates at various speeds(2inch ice ball for 5 speeds, 1inch ice ball for 3 speeds). As the results, the specific support force of the laminated plate and its back plate strain under different working conditions are obtained. It is found that the impact reaction force of the 1 inch ice ball is basically proportional to the impact energy, and the law of the 2 inch ice ball is slightly different due to the fixing method of the laminated plate; in terms of strain caused by impact, it is concluded that the maximum strain at the contact portion of a 1 inch ice ball at an impact speed of 88 m / s is 10300με; at the same time, a high-speed camera was used to record the process of the ice ball impacting the target plate, and the damage of the ice ball at the instant of impact and the deformation form of the laminated plate were observed and analyzed.
Microstructure and photocatalytic activity of TiO2-SiO2 composite materials
Authors: Wang Jun , Zhang Wenjuan , Zhu Binghua , Xiao Yueyuan
Published: November 2020

TiO2-SiO2 composite materials with different composition (from 0 to 50 mol % SiO2) were prepared by sol-gel method. Microstructure, optical property and photocatalytic activity of TiO2-SiO2 composite materials were characterized by Raman scattering, ultraviolet-visible (UV-vis) spectrometer and photocatalytic degradation of methylene blue. The Raman spectra results showed that TiO2-SiO2 composite materials contained only a single crystalline phase of anatase TiO2. It also indicated the inclusion of SiO2 suppressed the growth of anatase TiO2. The UV-vis absorption spectra showed that the absorption edge of TiO2-SiO2 composite materials has a blue shift as the SiO2 increased. The optical band gap of TiO2-SiO2 increased from 3.06 eV to 3.32 eV for TiO2 and 0.5TiO2-0.5SiO2. The adsorption performance and photocatalytic activity of TiO2-SiO2 was enhanced with the increase of SiO2 content. 0.5TiO2-0.5SiO2 has the best absorption performance and photocatalytic activity in our experiment. And it has potential application value in the field of photocatalytic materials.
Mixture Strength of Recycled Concrete Based on Structural Forms
Authors: Liu Haitao
Published: November 2020

In order to test the application of recycled concrete with different particle grading in the road base, strength tests of different structural forms of the mixture are designed; the results show that the seven day strength of the mixture can meet the requirements of the road base, and the compressive strength of the skeleton dense structure is the highest. It is suggested that appropriate equipment should be used to process concrete waste and produce recycled materials with dense skeleton structure.
Study on stress relaxation characteristics of Fe based memory alloy based on strain constraint
Authors: Liu Linlin , Chen Peijun , Du Jinqiao , Wang Xinyi
Published: November 2020

The characteristics of stress induced ε martensitic phase transformation and its stress relaxation during tensile stopped loading of Fe-17Mn-5Si-10Cr-5Ni alloy under constant strain constraint were studied by X-ray diffraction. The results showed that the amount of stress-induced martensite of the alloy could be increased effectively under the constant strain constraint condition when the constant strain stopped loading for 0~10 min. The stress relaxation ratio of Fe-Mn-Si memory alloy increased sharply when the constant strain stopped loading for 0~5 min, and the relaxation ratio increased slowly after 5 min, indicating that the stress-induced γ→ε phase transformation was mainly completed within 5 min. Thermo-mechanical training not only improved the shape memory effect of Fe-Mn-Si memory alloy, but also reduced the stress relaxation ratio of the alloy. The characteristics of Fe-Mn-Si memory alloy should be considered when it was applied in practical engineering.
Study on Microstructures of Complex Plant Polysaccharides Aerogels and Their Effects on Porosity
Authors: Zheng Han , Wang Hao , Tian Yuan , Wang Xu , Tian Yongfeng , Zhan Jianbo , Fu Rongrong
Published: November 2020

The microstructure of polysaccharide aerogels is a key factor affecting porosity, and directly determines the efficiency of its application as filter rod material. Scanning electron microscopy was used to observe the effects of different amounts of starch on the microstructure of the complex plant polysaccharide aerogels. The experimental results showed that the aerogel samples showed a complete and homogeneous three-dimensional network structure. With the increase of starch content, the pore size became smaller and the pore structure on the hole wall became smaller. After adding starch, the concentration of the system increased, that is, the solute in the unit volume increased, the moisture content decreased, and the air replaced the water in the gel after freeze drying, resulting in the increase of the density of the aerogel and the decrease of porosity. All aerogels showed a trend of increasing filtration efficiency with increasing particle size. The filtration performance of aerogels with different starch content was tested by using the comprehensive performance test bed of filter media. The test results showed that the capture of filter material was mainly through inertial collision. When the particle size was bigger, the greater the inertia, the greater the possibility of particle contamination being captured, so the higher the filtration efficiency.
Progress in Preparation Methods and Applications of Inorganic Nanoparticles
Authors: Li Ruoxi
Published: November 2020

Nanotechnology is a new technology with great potential. It can be combined with many physical, chemical and biological methods to develop many nanomaterials with good properties, such as nanoparticles, nanofilms and nanoemulsions. Combining with the domestic and foreign research literatures, this article summarized the preparation methods and applications of the inorganic nanoparticles, introduced the solvothermal method, sol-gel method, thermal decomposition, electrochemical deposition and other preparation methods in detail, as well as application in catalysis, drug delivery, chemical energy storage. The research status and the development direction of inorganic nanoparticles were summarized and prospected, which might be contributed to the future research of nanoparticles.
Improved the response time of WO3 thin film by deposition of Ag nanolayers
Authors: Zhao Lin , Song Shipai , Li Le
Published: November 2020

The effects of different Ag layer thicknesses on the optical properties of WO3-Ag-WO3 composite films are studied by magnetron sputtering. The research of WO3-Ag-WO3 composite films reveals that the introduction of Ag layer is not conducive to improving the transmittance ability of the film, and the transmittance modulation amplitude decreases with the increase of Ag layer thickness. However, with the increase of the Ag layer thickness, the response time and the cycle stability of the films have been significantly improved. However, electrochromic performances will decline when Ag was sputtered too long. Taken together, in this experiment, when the sputtering time of Ag layer is about 6min, the electrochromic device assembled by composite thin film can obtain the most excellent electrochromic performances.
Study on Mechanical Properties and Micro Morphology of Acetate Filter Rod before and after Partial Degradation
Authors: Wang Hao , Zheng Han , Zhan Jianbo , Wang Xu , Fu Rongrong , Zhang Ling , Li Geng , Yu Yao , Zhang Ying
Published: November 2020

Mechanical properties and micro morphology of acetate filter rod before and after partial degradation were studied. In this paper, the mechanical properties and micro morphology of acetate filter rod samples and 28 days soil burying were compared by means of Scanning Electronic Microscopy (SEM), texture analysis, infrared spectrum analysis and thermos-gravimetry (TG) analysis. The results showed that after degradation, the average compression modulus, hardness and elasticity of cellulose acetate filter rod decreased by 15.14%, 15.19% and 0.82%, respectively. The infrared spectrum analysis showed that cellulose acetate was degraded by soil burying method and carboxyl carbonyl was formed, but the degradation degree was not high. The degradation degree of cellulose acetate was lower than that of cellulose acetate before degradation. The weight loss zone between 110 °C and 230 °C is less, which may be due to the complete degradation of the small molecular assistant added to the cellulose acetate degraded by the soil burying method.
A new design of 1×2 optical switch with silicon waveguide and phase change material
Authors: Li Yu , Liu Furong , Huang Yin , Chen Qingyuan
Published: November 2020

On chip photonics devices relying on the weak, volatile thermo-optic or electro-optic effect of silicon usually suffer from high energy consumption and low refractive index coefficient. In this paper, we designed a 1×2 phase change optical switch. The device is implemented in two silicon waveguides system using an overcladding layer of the phase change data storage material Ge2Sb2Te5 (GST), which exhibits high contrast in its optical properties upon transitions between its crystalline and amorphous structural phases. The switch shows cross-state and bar-state corresponding to amorphous GST (a-GST) and crystalline GST (c-GST), respectively. The characteristic parameters of the switch were carefully designed and simulated by three-dimensional finite-difference time-domain (3-D FDTD) method. As the simulation result, the insert loss was less than 0.5 dB. The crosstalk was -16 dB for cross-state and -29 dB for bar-state at 1550nm.The device performance can be further optimized and the low consumption phase change optical switch can be expected for future optical communication networks.
Properties of High Speed Friction Stir Welded 6063-T6 Aluminum Alloy
Authors: Xu Anlian
Published: November 2020

Friction stir welding (FSW) is as known as a revolutionary welding technology, which has come to the foreground in recent years. The low welding speed affects the efficiency of friction stir welding (FSW) and hinders the large-scale commercial application of FSW. In order to improve the welding speed and promote the application of FSW, 6063-T6 aluminum alloy plates were friction stir welded with welding speed of 3000 mm/min. The properties of welds were also tested and analyzed. The results show that the alloy plates can be successfully welded by FSW with high speed welding speed, and the tensile strength of weld can reach over 71 % that of the base material.
Application of Ultrasonic Phased Array Detection Technology in Steam Turbine Components
Authors: Xuechao ZHANG , Feng YUN , Lei LV , Tong FENG
Published: November 2020

Ultrasonic phased array detection technology has the characteristics of fast, high sensitivity and recordable. The application of ultrasonic phased array detection technology to diaphragm, rotor, bolt and other turbine metal parts can effectively improve the detection rate of micro defects. At the same time, the development of reliable detection process can avoid the limitations of its detection and ensure the safety and reliability of turbine metal equipment.
Modal analysis on swinging structure of hydraulic press
Authors: Xiaoying Wang , Xiaowei An
Published: November 2020

In the actual work of hydraulic press, in order to ensure the design of auxiliary punching structure, that is, swing punching structure runs smoothly, the modal analysis of swing punching structure is carried out by using ANSYS software. The first 40 natural frequencies are determined, and the first 10 modes are analyzed. The shape variables and deformation modes are determined. Thus, the actual vibration response of the structure under the action of various external or internal vibration sources in each frequency band can be predicted to avoid resonance phenomenon in the work. At last, the aim of safety production, material saving and cost reduction is achieved.
Research on the application of phased array detection in Power transmission and transformation metal equipment
Authors: Xie Liming , Zhang Yanfei , Zhang Tao , Zhang Xuechao , Lv Lei
Published: November 2020

This paper analyzes and compares the characteristics of conventional nondestructive testing method and ultrasonic phased array testing method, and introduces several ultrasonic phased array testing methods of power grid equipment. Ultrasonic phased array technology is a high-efficiency, intuitive and reliable new nondestructive testing technology. It is of great significance to apply ultrasonic phased array technology to the nondestructive testing of power industry equipment and explore the adaptability of its testing technology to ensure the reliable operation of equipment and the security of power grid.
Topology Optimization of Welding Spots for Stainless Steel Subway Vehicles
Authors: Yana LI , Dejian SONG , Man ZHANG
Published: November 2020

Taking the head car body of the stainless steel subway as an example, the static strength of the vehicle body and the shear strength of the welding spot is checked according to different thicknesses and weld nugget diameters under dangerous conditions. For the unqualified position of the welding spot strength, the welding spot layout schemes are improved. At the same time, the topology optimization is performed for the main welding spot layout areas in the scheme improvement. The optimization results show that the number of welding spots is reduced by 49.33% and 52.04% compared with the original scheme and the improvement scheme respectively under the premise of ensuring the structural strength. The obvious optimization effect provides a useful reference for the future design of stainless steel spot welding subway vehicles.
Dynamic Recrystallization Behavior and Model Study of Equiaxed Fine Grain Structure TC4
Authors: Yi Zong-xin , Li xiao-qiang , Pan Cunliang
Published: November 2020

Thermal compression test of equiaxed fine grain structure TC4 was conducted by using Glebble-3800 testing machine. The deformation temperature ranged between 800-950 °C, the strain rate ranged between 0.01-10 s−1, and the deformation was 60%. The dynamic recrystallization behavior under this condition was analyzed. The results show that the dynamic recrystallization behavior of equiaxed fine grain structure TC4 is sensitive to temperature and strain rate. The grain size and volume ratio of dynamic recrystallization increases with increasing temperature and decreases with increasing strain rate. In this paper, with the β-phase transition temperature as the boundary, a dynamic recrystallization critical strain model, a dynamic model and a critical size model of the equiaxed fine grain TC4 are established. The predicted value of the established constitutive model is in good agreement with the experimental value, which provides a theoretical basis for the microstructure control of the alloy during plastic processing.
Preparation of Fluoramphibole Glass Ceramics by The Mechanochemistry Method
Authors: Si Wei , Li Shuangyu
Published: November 2020

The fluoramphibole glass ceramics were successfully prepared by mechano-chemistry method using waste glass and fluormica powder. The effects of ball milling parameters on synthesis of fluoramphibole glass ceramics were studied by means of XRD and SEM. The mechanical properties of the samples were discussed. The results show that the optimum preparation conditions were as follows: the processing of 10 to 1 ball to powder weight ratio, rotation speed of 800 rpm and milling of 45 minutes. Under these conditions, the highest value of modulus of rupture for fluoramphibole glass ceramics is 41.73 MPa.
Numerical simulation of laser-arc hybrid welding of high strength steel
Authors: Fulong ZHANG , Hong ZHANG , Shuangyu LIU , Fengde LIU
Published: November 2020

The numerical simulation of high-strength low-alloy steel in the welding temperature field is carried out. The SYSWELD special welding analysis software is used to establish the geometry model of the butt joint of the flat Y-shaped groove. The temperature field of single-layer and multi-layers welding of 12 mm high-strength low-alloy steel provides a theoretical basis for the welding process and has engineering practical value.
Research on the influence of end effect on forming result of saddle curved part in flexible rolling process
Authors: Li Yi , Yan Xin-yue , Li Ming-zhe
Published: November 2020

Flexible rolling is suitable to manufacture small batch of 3D curvature parts with various shapes. In this paper, the influence of end effect on saddle curved part was studied firstly. The finite element model was designed based on the flexible rolling forming apparatus. The areas characteristics of forming saddle curved part were analysed, and the influence of end effect on the saddle curved part with different forming size was studied. The results demonstrate that: the forming saddle curved part consists of three forming areas by characteristics, and the forming mechanism of each forming area is analyzed deeply; under the end effect action, with the sheet length increases, the plastic strain and minimum forming thickness of forming curved part are stable; when the sheet length is 200mm, 300mm, 400mm and 500mm, the percent of the stable forming area of forming curved part is 52%, 72%, 79% and 83% respectively, and the percent of stable forming area increases by 20%, 27%, 31% respectively, therefore the utilization rate is obviously improved. With the increasing sheet width, the plastic strain is increasing and the minimum forming thickness is decreased; when the sheet width is 85mm, 90mm, 95mm and 100mm, the percent of stable forming area of forming curved part is 67%, 61%, 59%, 58% respectively, and the percent of stable forming area decreases by 6%, 8%, 9% respectively, therefore the utilization rate is decreasing.
Failure analysis of Desuperheater
Authors: Zhang Xuechao , Zhang Yanfei , Yun Feng , Cheng Lu
Published: November 2020

Temperature regulation by desuperheater spray is an important part to ensure the stable operation of utility boiler. However, due to the bad working conditions, the spray pipe of Desuperheater will produce strong vibration, and the connected equipment will have alternating stress. At the same time, due to design or manufacturing reasons, abrasion or cracking occurs at the welding part or the contact part between the water spray pipe and other parts. Taking measures to ensure stable operation, reasonable design and qualified manufacturing can effectively guarantee the safe operation of power plant equipment.
Design and analysis of automatic transmission for Ravigneaux transmission with four speed
Authors: Song Xiaoyan
Published: November 2020

The automatic transmission can automatically choose the gear according to the engine condition and the running speed of the car. In this paper, according to the structure characteristics of planetary gear mechanism, the different combination of shift actuators, get the movement rule and working principle of each gear position, calculated the specific parameters of each row of planetary gear mechanism. Next the article take Ravigneaux type of four gear automatic transmission for example, complete the design of automatic gearbox transmission mechanism, include various gear transmission route and the transmission scheme design, finally through the concrete parameters, finish the structure design of the whole planetary gear transmission part.
A Cooperative Path Planning Algorithm for Handling Robot
Authors: Cai Li , Zhu XiaoLing , Li Jingchuan
Published: November 2020

Path planning is one of the core research fields of the handling robot, which has the characteristics of complexity and constraint. Ant colony algorithm is a search algorithm developed in recent years, which has good performance and development potential in solving many complex problems. In this paper, ant colony algorithm and workspace modeling are used to determine the optimal path for the global path search algorithm of the handling robot. The results of spatial modeling and software simulation show that the ant colony algorithm has advantages in the path planning of the handling robot. This path planning algorithm can provide the corresponding solutions for the search path problem of the complex robot.
Research on simulation training method based on computer simulation technology
Authors: Huang Shaoluo , Li Siyu , Meng Shuo , Wu Weiyi , Wang Handong , Su Kai , Peng Rui
Published: November 2020

Simulation training is based on virtual reality and computer simulation technology as the main technical support, so as to realize the combat method of training personnel in the virtual battlefield environment, weapon system operation, joint operations under the battlefield environment, including operational method of simulated training, simulation training as a military exercise method has important practical significance.
Influence of annealing conditions on tripe-layer TiO2/Si3N4/SiO2 antireflection coatings for GaAs solar cells
Authors: Wu Liyu , Li Xiaoqiang
Published: November 2020

In this work, TiO2/SiO2/Si3N4 triple-layer antireflection coatings (TLARC) were prepared on GaAs substrate by RF sputtering and Plasma Enhanced Chemical Vapor Deposition (PECVD). Influence of annealing conditions on the structure and optical properties of TLARC were also investigated. The structure and optical proprieties were analyzed by Grazing Incidence Angle X-ray Diffraction (GIXRD) Fourier Transform Infrared Spectroscopy (FT-IR), Atomic Force Microscopy and UV-VIS spectroscopy. The experimental results were summarized as follows: diffraction peaks of SiO2, Si3N4 and TiO2 respectively appeared in the as-deposited status, and after annealing, new diffraction peak at 25.2° corresponds to TiO2 was confirmed by checking out PDF cards; Stretching vibration of Ti=O, Si-O-Si and N-Si-N was confirmed by FT-IR spectrum; The average reflectance of the TLARC after annealing at 750 °C and holding for 5 min reached the lowest value, which was approximately 7.84 %.
Research on improving VAC of auto-stereoscopic 3D display via monocular multi-view
Authors: Huo Yingdong , Zhang Jing , Wang Ronggang
Published: November 2020

The auto-stereoscopic 3D display technology is the most widely used 3D display technology nowadays, but its problem of vergence-accommodation conflict (VAC) remains to be solved. This paper proposes a novel method to solve this problem via monocular multi-view, aiming to alleviate the discomfort caused by VAC. By utilizing the light splitting of the parallax barrier and a specific rendering algorithm, we generate multiple images from different angles in a viewing zone. In this way, each eye can receive more than two images, thereby easing VAC through the automatic blurring adjustment of human eyes.
Research on the service topic of intelligent electricity meters’ full life cycle quality cloud service platform
Authors: Wang Yong , Zheng Angang , Shang Huaiying , Liu Yan
Published: November 2020

The whole life cycle management of intelligent electricity meters is dependent on the construction of "Internet +". This paper introduces the design concept and method of the intelligent electricity meter quality in whole life cycle cloud service platform, the application of scenario planning principles is proposed based on the cloud service platform. This paper analyzes the regulatory agencies, power companies, production enterprises and the public’s present situation and the pain points in whole life cycle of the intelligent electricity meter management, and researches the present situation and the spot application scenarios according to the principle of planning design, including the design idea and implementation framework of the application scenarios, laying the foundation for the construction of cloud service platform. It provides a new direction and method for the whole life cycle management of intelligent electricity meters.
Study on the shape change of crack growth rate curve under different forms of additional stress field
Authors: Jing Wang , Chenxi Song , Xiaolin Shao
Published: November 2020

In this paper, FRANC3D is used to simulate the fatigue crack growth process under different additional stress fields to explore the key mechanical parameters influencing the fatigue crack growth curve. For finite large plate model with penetrating crack, the crack growth rate is calculated under different forms and different values of applied load and additional stress coupling, the fatigue life curves, as well as crack growth rate curves and Pairs formulas under different applied loads are obtained. Through the analysis, the relationship between the additional stress field and the parameters in Pairs formula of crack growth rate is obtained. Because of the existence of the additional stress field, the stress intensity factor amplitude of crack tip changes, which is the root cause of the change of crack growth rate curve shape.
A First Principles Study of Electric Structures of Heterostructures Built with Blue Phosphorene
Authors: Bao Jinna , Li Hui , Hou Jianhua , Tian Jian
Published: November 2020

we have built the heterostructure with 2D materials C3N and BN capping on blue phosphorene. The geometric structure and electric structure of the heterostructures have been investigated by using first-principles computations. Calculated results indicate that the strong interaction exists between the two 2D materials due to the equilibrium interlayer distances in the range of 3.31 Å and 3.30 Å. Moreover, the 2D capping layers not only protect blue phosphorene from being oxidized, but also can improve the band structure of blue phosphorene.
Study on mechanical properties and wear resistance of aluminum alloy composites reinforced by basalt fiber
Authors: Wang M , Zhang X , Zhou L F , Cheng L L
Published: November 2020

Basalt fiber is a new type of environmentally friendly materials with excellent performance in the 21st century. Basalt fiber (BF) reinforced aluminum alloy composites with different length-diameter ratios (200:1, 400:1), different volume fraction (1%, 4%, 8%) was fabricated by room-temperature pressing and vacuum sintering method. It was found that the BF treated with electroless copper plating on the surface enhanced the mechanical properties and wear resistance of the composites, while the BF without copper plating on the surface weakened the hardness. With increasing the volume fraction of BF with copper plating, the hardness and the wear resistance of the composites increased. The length-diameter ratio ∼400:1 is superior enhancement aspect ratio of 200:1 of the reinforcing effect.
Effective Thermal Conductivity for Low Density Silicon Nitride Porous Ceramics
Authors: Bi Cheng , Lu Yuan , Yang Xu
Published: November 2020

Thermal conduction in porous materials generally includes four heat transfer forms, i.e. heat transfer via the gas phase, heat conduction along the solid matrix/skeleton, thermal radiation and gas-solid coupled heat transfer. The size effects on the gas and solid thermal conductivities are introduced to predict the effective thermal conductivity of the silicon nitride porous ceramic at room temperature, and the predictions from the random model present good agreements with the experimental data. The effect of the porosity on the effective thermal conductivity of the low density silicon nitride porous ceramic are studied as well, and the low density porous ceramics can achieve a low thermal conductivity in the range of 0.08-1.2 W/m K for a good performance of thermal insulation.
Preparation of zirconia fiber based on akund template
Authors: Yu QinKun , Liu Xinyu , Zhang Jingwen , Yin Fuyan , Lai Junjie , Wang Tianchi
Published: November 2020

Zirconia fiber is widely used in the field of fire resistance and heat insulation because of its excellent thermal insulation performance. In this study, the hollow plant fiber, akund, was used as template to prepare zirconia fibers with hollow structure. SEM, XRD, mercury porosimetry, and TG-DSC were used to characterize the microstructure, phase and crystal structure, pore size distribution, and formation process of the zirconia fiber. The analysis shows that the hollow structure restricted the air flow and was conducive to the improvement of thermal insulation performance. Yttria doping mae the phase of zirconia fiber stable. Lower heat treatment temperature made the grain size smaller. The concentration of impregnating solution can influence on the fiber morphology.
Selection of Abrasive for Chemical Mechanical Polishing of the 304 Stainless Steel
Authors: Jianxiu Su , Haixu Liu , Wanting Qi , Xiaojun Cao , Zhankui Wang
Published: November 2020

Chemical mechanical polishing (CMP) technology is widely used in ultra-precision machining of various materials, and the abrasive are an important component of CMP slurry. In this paper, the effects of the abrasive type, the abrasive size and its concentration on material removal rate (MRR) and surface quality in CMP 304 stainless steel were studied through a series of experiments. The results show that the MRR in CMP 304 stainless steel using slurry with the white corundum abrasive is the highest, and the MRR in CMP 304 stainless steel using slurry with the silica abrasive is the lowest, but the surface quality in CMP 304 stainless steel using slurry with the silica abrasive is the best. The MRR and surface roughness increase with the increase of abrasive size, but the surface roughness increases slowly with the increase of abrasive size. With the increase of abrasive concentration, the MRR first increases and then decreases, while the surface roughness value changes slightly, indicating that the abrasive concentration in polishing slurry has little effect on the surface quality. These research results can provide a reference for the design of CMP slurry.
Study on Friction and Wear Behaviors of Micro Texture Shape and Its Modified Surface
Authors: Rui Xu , Yipu Wang , Haixu Liu , Wanting Qi , Zhankui Wang , Jianxiu Su
Published: November 2020

The 304 stainless steel has good mechanical properties and is widely used in industrial manufacturing. In this paper, take 304 stainless steel as the substrate material, the five micro texture shapes, such as groove array, square column array, circular pit array, regular hexagon column array and trapezoid column array, on the surface of 304 stainless steel were carved by nanosecond laser engraving machine under the same parameters, and then were immersed in 0.5mol/l perfluorodecyl trimethoxysilane ethanol solution at 45 °C for 5 hours. Five type super-hydrophobic surfaces were obtained. A series of friction and wear experiments were conducted out and the influence of different micro texture on the friction and wear to the 304 stainless steel surface was analyzed. The results show that the square column array has the best friction and wear resistance, and its friction coefficient is 0.16, which is the lowest in all other micro texture shapes. It can be used as a reference for improving the friction and wear resistance of metal surface.
The effect of use E85 ethanol fuel on a five-stroke engine
Authors: Noga M
Published: November 2020

The article presents the analysis of the impact of the use of E85 ethanol fuel on operating parameters and toxicity of exhaust gases of a spark ignition engine with an additional expansion in a separate cylinder. Such an engine in literature most often referred to as five-stroke was developed at the Cracow University of Technology (CUT). The use of additional exhaust expansion was aimed at achieving high thermal efficiency when working with an average high load. The engine developed in CUT is equipped with a turbocharger and direct fuel injection, hence the use of fuel with high ethanol content was aimed at the effective use of these attributes. The obtained results indicated an improvement in the brake thermal efficiency of the engine when fuelling with E85 in relation to the gasoline of 98 octane rating normally used for this engine. On the other hand, the efficiency of the conversion of the catalytic converter has deteriorated somewhat. Directions for further activities and research in the subject were also determined.
Chemical content analysis of coral limestone as prospecting of extractive development in Gorontalo City
Authors: Annisa W , Manyoe I N , Mubarak A K , Napu S S S , Pratama I G S , Fatimah S
Published: November 2020

The potential of limestone in Gorontalo City is very large and distributed over a wide area. This enormous potential has not yet been exploited. This study aims to determine the chemical content of limestone and the use solution of limestone to improve regional development. Field data collection was carried out in two places, namely Tanjung Keramat and Buli’ide. Sampling was conducted at the coordinates N 0°29′38.93″ and E 123°2′49.62″ for station 1, N 0°32′53.7″ and E 123°1′56.19″ for station 2. The method used in this research is chemical composition analysis using X-Ray Fluorescence (XRF). The results of the analysis of the chemical constituents of Coral Limestone are CaO 83.35%, Fe2O3 6.92%, SrO 9.35% and ZrO2 3.25%. The prospect of Coral Limestone can be used in various industrial fields. Coral Limestone can be used in the mining industry, the cement industry, the sugar industry, ceramic raw materials, building materials, agricultural and road stabilizers. This indicates that the City of Gorontalo has the prospect of development and utilization of limestone resources available, in order to encourage self-reliance and open employment for community.