bluuebunny/crossref_metadata_2025_split huggingface dataset:
Preparation and Characterization of Transparent Glass Ceramics Containing Na3Gd(PO4)2
Authors: Chen Xi , Zhang Hongbo , Zou Xiangyu , Su Chunhui 
Published: November 2019

Abstract
Transparent glass ceramics with the mole percent composition of 21.3Na2CO3-2.2Gd2O3-38SiO2-36.5H3BO3-2.0P2O5 were prepared by melting crystallization method. The heat treatment system, crystal phase, micromorphology and transmittance of the samples were tested and characterized by differential scanning calorimetry analysis(DSC), X-ray diffraction (XRD), scanning electron microscopy(SEM) and UV-Vis-NIR, respectively. The optimum heat treatment condition is 730°C for 2h. The Na3Gd(PO4)2 crystal phase were precipitated homogeneously among the glass matrix. The results of FTIR spectra confirmed the presence of PO4 groups in the glass ceramics samples. The refractive index of glass ceramics and glass samples were measured. In the visible region, the transmittance of glass ceramics is up to 80%.
Fabrication of Silicon Nitride Fiber Materials by Organic Foam Impregnation Method
Authors: Wang Gang , Zhang Qi , Han Jianshen , Zhao Xin , Li Hongxia 
Published: November 2019

Abstract
In this paper, porous silicon was prepared by organic foam impregnation, and silicon nitride fibers were prepared by direct in-situ nitridation of porous silicon. The effect of pore structure of porous silicon on material properties was studied. The results show that the silicon nitride fiber material with low density, high strength and low thermal conductivity can be obtained by using organic foam impregnation method. The pore size of template has a certain effect on the growth of silicon nitride fibers. The smaller the pore size of the template, the higher the content of silicon nitride in silicon nitride fiber material. This is due to the concentration of gas phase reactants in pore.
Fabrication of Al2O3-Bonded Fibrous Ceramics by An Aqueous Gel-Casting Process
Authors: Liu Zhenli , Yu Jingkun , Tian Chen , Li Chaoyue , Yuan Lei 
Published: November 2019

Abstract
The traditional gel-casting method mostly uses organic compounds, which are complex process, expensive and pollute the environment. In order to overcome the disadvantage of the traditional gel-casting method, an environment friendly aqueous gel-casting process is introduced in this paper. Al2O3-bonded fibrous ceramics with high porosity and low thermal conductivity have been prepared by a novel hydrated alumina gel-casting process using the ρ-Al2O3and mullite fibers or YSZ fibers as raw materials and the deionized water as hydration agent. A bird-nest-patterned three-dimensional reticular skeleton structure was established by the fibers to ensure a certain mechanical strength. The effects of the amount of mullite fibers andYSZ fibers on the properties of porous ceramic, such as phase composition, microstructure, sintering behavior and relative properties were investigated. Results showed that the as-prepared Al2O3-bonded fibrous mullite ceramics have high porosity of 66.9%∼78.6%, low thermal conductivity of 0.236∼0.479 W/m·K, and relatively high compressive strength of 0.80∼2.78 MPa. The as-fabricated fibrous YSZ ceramics had a high porosity (71.1%∼72.7%), a low thermal conductivity (0.209∼0.503 W/m·K) and a relatively high compressive strength (3.45∼4.24 MPa). Comparing to the as-fabricated fibrous mullite ceramics, the compressive strength of as-fabricated fibrous YSZ ceramics is promoted obviously.
Magnesium Phosphate Cements/GNPs Composites by Combustion Synthesis and Acid-Base Reaction
Authors: Lu Nan , Liu Jiaxi , He Gang , Li Jiangtao 
Published: November 2019

Abstract
Magnesium phosphate cements (MPC)/graphene nanoplatelets (GNPs) composites were fabricated by combustion synthesis and acid-base reaction. MgO/GNPs mixture powders were obtained by the combustion reaction between Mg powders and CO2 gas. The composites were prepared by mixing MgO/GNPs mixture powders with potassium dihydrogen phosphate (KH2PO4) using borax as retarder. The effect of GNPs content on mechanical and functional properties of the prepared MPC/GNPs composites was investigated. The results show that this MPC/GNPs cements mainly consisted of MgO and KMgPO4•6H2O. Moreover, the crystallinity of KMgPO4•6H2O in lower surface is better than the upper surface due to the difference of temperature. With incorporating small amounts of GNPs into MPC, the spectral absorptivity of the composite was improved to 0.95 in most spectral regions. Nevertheless, the compression strength shows little change with changing the GNPs content, which may be attributed to use coarse MgO powder as reactant. In virtue of short processing time and homogeneous distribution of GNPs, the novel fabrication provides a new route for preparing GNPs-cement based composites.
In-situ Synthesized Mullite Whiskers on the Surface of Aluminum Silicate Fibrous Felts with Low Thermal Conductivity and High Compression Rebound Performance
Authors: Liu Jiapeng , Guo Anran , Liu Jiachen , Hou Feng 
Published: November 2019

Abstract
In this study, in situ synthesized mullite whiskers on the surface of aluminum silicate fibrous felts was prepared by gas-phase deposition and reaction. Effects of the concentration of impregnation solutions on the density, thermal conductivity, microstructure and the compression rebound performance of the fibrous felts during the in situ synthesized mullite whiskers process were analyzed. The mullite whiskers were generated on the surface of aluminum silicate fibrous felts through gas-phase deposition and reaction of AlOF and SiF4, which proved that the mullite whiskers could form on the aluminum silicate fibers in this process. The results showed that the materials fabricated at the optimum process showed a high compression resilience ratio (94.6%) after compression to a compressive strain of 10%, meanwhile the density and the thermal conductivity of the sample fabricated at the optimum process were 0.1536g/cm3 and 0.04102 W/(m*K), respectively.
Near-Infrared Emission Property of ZrC-TiC Solid Solution Prepared by Combustion Synthesis
Authors: Li Honghua , Shuang Shuang , He Gang , Yang Zengchao , Li Jiangtao 
Published: November 2019

Abstract
ZrC-TiC solid solutions are considered as a promising candidate for ultra-high-temperature structural applications. Zr
x
Ti1-x
C (x=0, 0.2, 0.4, 0.6, 0.8, 1.0) solid solutions have been prepared by combustion synthesis method using Zr, Ti and C elemental powder. The effect of Zr/Ti mole ratio on the phase composition, microstructure, oxidation resistance and near-infrared emission property of the synthesized samples were investigated. It was found that the prepared samples with different Zr/Ti mole ratio all have formed a single cubic structure. The grain size of Ti rich solid solution developed to a larger size than that of Zr rich samples. Zr
x
Ti1-x
C solid solution with x=0.4 has a higher starting oxidation temperature of ∼650°C than that of the other solid solution samples. The prepared solid solution with x=0.4 also shows the largest emissivity of 0.79 in 0.75-2.5μm and 0.76 in 3-5μm wavelength range. The prepared Zr
x
Ti1-x
Csolid solution samples by combustion synthesis method, which exhibit good near-infrared emission property could be regard as a promising ablation resistant material.
Electrical Conduction and Impedance Behavior of Sr0.97Ti0.6Fe0.4O3-δ Electrode Containing YSZ for Various Applications
Authors: Yi Zhong-Zhou , Zhai Fengrui , Li Nan , Shan Ke 
Published: November 2019

Abstract
Sr0.97Ti0.6Fe0.4O3-δ (STF) and 8 mol% Y2O3 stabilized ZrO2 (YSZ) composites were prepared by mixing them in different weight fractions. The composites were compacted into discs, sintered and evaluated for phase stability, microstructure and mixed ionic-electronic conductivity. Phase analysis by XRD showed no clearly detectable secondary phases. Chemical analysis by energy dispersive spectroscopy (EDS) also showed the diffusion of elements (especially Y and Zr from YSZ). The electrical conductivity measurement on the STF-YSZ composites showed a decrease in total electrical and ionic conductivities with YSZ amount increasing. And the ionic conduction mechanism was concerned by impedance behavior analysis.
Effects of TiO2 Content on Microwave-Attenuating Properties of TiO2-Al2O3 Composite Ceramics
Authors: Wang Shiyuan , Zhang Yingchun 
Published: November 2019

Abstract
Microwave attenuation ceramic is a kind of dielectric loss material, which is used to absorb some unnecessary microwave electromagnetic field energy. For this attenuation material, it is required to have a large attenuation ratio, a sufficient mechanical strength and a good thermal stability. In this work, TiO2-Al2O3 composite ceramics were prepared via the conventional pressureless sintering method. The addition of CuO as liquid phase sintering aid was used to lower the sintering temperature of TiO2-Al2O3 composite ceramics. The effects of TiO2 content on sintering properties, phase composition, microstructure, mechanical properties and microwave-attenuating properties were investigated. With the increase of TiO2content, the sintering temperature decreased from 1300°C to 1100°C, meanwhile the dielectric constant rose from 15.42 to 23.80 and the dielectric loss increased from 0.042 to 0.314, which improved the attenuation of the TiO2-Al2O3 attenuation ceramics. When the content of TiO2 was 10 wt%, TiO2-Al2O3 composite attenuation ceramics with good properties could be obtained.
A study on Electrostrictive Properties of Ba2+, Bi3+, Eu3+ Doped PLZT (9/65/35) Transparent Ceramics
Authors: Chen Yijie , Zeng Xia , Cao Zhaodong , Ling Liang , Qiu Pingsun , He Xiyun , Sun Dazhi 
Published: November 2019

Abstract
Lead lanthanum zirconate titanate (PLZT 9/65/35) transparent ceramics, which modified with Ba2+, Bi3+, Eu3+ respectively, were prepared by hot-press sintering method. The phase structure, microstructure, ferroelectric, dielectric and electrostrictive properties of all the samples were examined and analysed. All of the ceramics show a pure perovskite phase and dense microstructure by the X-ray diffraction (XRD) and scanning electron microscope (SEM). Compared with undoped PLZT ceramics, the peak of the temperature-dependent of the dielectric constant curves with Ba2+ doped shift slightly to low temperature, meanwhile the Bi3+ and Eu3+ peak of the temperature-dependent dielectric constant curves decreases and broadens, which imply the relaxation of the as doped PLZT lattice. The hysteresis loops of Ba2+, Bi3+, Eu3+ doped PLZT show that a lower remanent polarization and coercive field. The field-induced strain hysteresis loops of all the sample were measured. The electrostrictive strain and hysteresis of Ba2+ and Eu3+ doped PLZT decrease monotonically. However, the electrostrictive strain of Bi3+ doped PLZT is increased. The experimental result implies that the A-site vacancies are induced by Ba2+, Bi3+ and Eu3+, which is in accordance with previous investigations. The strain curves of transparent materials exhibit low hysteresis under DC electric fields and this effect can be used in relative applications for great potential.
The Fabrication and Electrocaloric Effect of Bimodal-Grain Structure (Ba0.60Sr0.40)TiO3 Using the Induced Abnormal Grain Growth Method
Authors: Zhang H F , Chen X , Gao J , Lam K H , Liang S D , Fei L F , Mak C L , Chen J F 
Published: November 2019

Abstract
Bimodal-grain structure (Ba0.6Sr0.4)TiO3 ceramics had been prepared using induced abnormal grain growth method (IAGG). Two grain size distributions, between 10 ∼ 20 μm and 100 ∼ 300 μm, were found during the sintering temperature of 1250 ∼ 1350°C. Our results suggested that the ultra-large grain exhibited the high dielectric and ferroelectric properties comparable to the single crystal. At the same time, the fine-grain caused a phase diffusion transition at the Curie temperature about 20°C. The direct measured electrocaloric effect showed that the best performance is achieved with ΔT of 0.6 K, and ΔS of 1.02 J kg−1K−1 near room temperature and electric field strength of 2 MV/m.
Electrospray Preparation and Microwave Absorption Properties of ATO Hollow Micro/Nanospheres
Authors: Zhao Fang , Tang Xiangjun , Wang Xinkun , Zhang Sa , Duan Rongxia 
Published: November 2019

Abstract
Sb3+-doped SnO2 (ATO) hollow micro/nanospheres were prepared through electrospray and calcination technique. The influences of the calcination temperatures (500°C, 600°C, 700°C) on the crystal structure, micromorphology and microwave absorbing property of the calcined products were characterized by means of XRD, FT-IR, SEM and vector network analyzer. The results showed that Sb3+-doped SnCl2/PVP precursor polymer were smooth spheres with diameters of around 0.35-2.1μm. The pure rutile structure of SnO2 formed at 500°C, and the Sb3+ entered the lattice of SnO2. When the calcination temperature is 500°C and 600°C, ATO micro/nanospheres appeared to be hollow structure, and the surface were made up of many small particles. When the calcination temperature is 700°C, the ATO grains grown up which contained in the micro/nanospheres, and lost the sphere morphology and presented the irregular granlar forms. The microwave absorption properties of ATO hollow micro/nanospheres calcined at 600°C was the best as the matching thickness was 2mm. The minimum reflectivity can reach -32dB at 10.8GHz, and the frequency band with reflectivity less than -10dB was 9.8-12.2GHz. The minimum reflectivity of ATO hollow micro/nanospheres moved to a low frequency as the matching thickness increased. When the matching thickness was 3mm, the microwave absorption peaks were double, at which the frequency band with reflectivity less than -10dB was widen.
Preparation and Characterization of Gd and Zn Doped Apatite Lanthanum Silicate Electrolyte
Authors: Wu C S , Lei H , Huang J S , Yao D H , Cheng Y L , Huang Z L 
Published: November 2019

Abstract
Apatite lanthanum silicate is an oxygen ionic conductor with high conductivity. In this paper, research the effects of Gd and Zn double doping in La9.33Si6O26+x
. Synthesis La9.33Gd
x
Si5ZnO25+3x/2 (x = 0.2, 0.4, 0.6, 0.8) by Sol-gel Self combustion method, Characterization of the synthesized phase and electrical properties by X-ray diffraction, Scanning electron microscopy and Electrochemical workstations. The results show that doping can effectively improve the conductivity, La9.33Gd0.2Si5ZnO25.3has best conductivity that reach 1.49×10−3S/cm in 500°C.
Injection Molding Cycle Time Reduction for Automobile Headlamp Shell in Moldflow
Authors: Fouodji Cedric Tiomela , Xiao Hua Huang 
Published: November 2019

Abstract
In the injection molding cycle, the cooling time consumes more than 70% of the molding process, optimizing the molding cycle time can be done through the selection and the design of appropriate cooling system that will be able to achieve equal distribution of the temperature along the part and quickly dissipate the heat. This paper presents an analytic study on the simulation of cool + fill + pack + warp in Autodesk Moldflow 2012 for the automobile headlamp shell, the simulation is made on of four different cooling systems, after comparison of the obtained results, the Spiral Zigzag Conformal Cooling Channel (SZCC) has the lowest time required for the part to reach the ejection temperature, with 61.22 seconds, it also shows an improvement on the volumetric shrinkage with the part’s deflexion that have been reduced from 2.15 mm on the first design to 2.12 mm, making Spiral Zigzag Conformal cooling the best solution for this model.
Adaptive Force Control for Robotic Grinding of Complex Blades
Authors: Zhou Pokuang , Zhou Yuming , Xie Qianlong , Zhao Huan 
Published: November 2019

Abstract
Aiming at solving the robotic grinding problem of aircraft engine blades with complex surface, this paper proposed an adaptive force control method using fuzzy PID algorithm, which can ensure that blade surface is completely polished to eliminate residual texture and harmful stress concentration. First, an intelligent digital compliant grinder with active and passive compliance was developed. Second, a fuzzy PID adaptive algorithm was proposed, which can stabilize the contact force between the grinder and the blade. Third, a protection scheme was proposed to prevent excessive grinding. In the polishing process, the robot arm was fitted with the blade. According to the surface profile of the blade, the robot arm moved in a specific trajectory, keeping the blade in contact with the grinder. During grinding, some parameters, such as the abrasive belt velocity, the abrasive belt type and contact force, could affect the quality of the grinding process. Therefore, appropriate parameters were selected. The experimental results showed that the actual force fluctuates within 0.5N. In addition, the original surface roughness was 1.672um, which was reduced to 0.054um by adaptive force control method, comparing to 0.589 urn with the non-force control. Not only is the contact force more precisely controlled, but the grinding accuracy is greatly improved.
Fatigue Life Calculation of High-Power Disc Brake under Thermal-Mechanical Coupling
Authors: Zhang Shengfang , Han Zhiyu , Hao Qiang , Liu Yu , Sha Zhihua , Ma Fujian , Yang Dapeng 
Published: November 2019

Abstract
The fatigue failure mode of the brake disc is the initiation and expansion of the fatigue crack on the surface of the brake disc until the brake disc brakes. Therefore, considering the fatigue failure mode of the brake disc, the fatigue life of the brake disc is calculated. Firstly, the thermo-mechanical coupling model of the brake disc and pad is established by Abaqus software, so that temperature and stress of the brake disc could be obtained. Then, the surface crack initiation life of the brake disc is calculated by fe-safe software Finally, the fatigue crack growth life of the brake disc is calculated by nCode software. The calculation and analysis results show that the fatigue crack of the brake disc appears on the outer side of the brake disc friction surface under the working condition of this paper. The crack initiation life is that the number of braking is 12830 and the crack propagation life is 695000for the number of braking.
Design and Analysis of Vegetable Transplanter Based on Five-bar Mechanism
Authors: Sun Kai , Ge Rongyu , Li Taoyuan , Wang Jiatai 
Published: November 2019

Abstract
As one of the important components of automatic transplanter, duckbilled planting device, is a significant factor affecting the efficiency of the transplanter. Aiming at the problems of low transplanting rate, poor upright angle and poor stability of the transplanter, a five-pole transplanting mechanism is designed. Firstly, the parameters of the five-pole transplanting mechanism are analyzed and confirmed by MATALAB software. After virtual prototype model is established by SolidWorks software, simplified model is imported into ADAMS software for kinematics simulation, and then the trajectory, velocity and acceleration curve of the duckbilled tip are obtained. The simulation results verify the rationality of the structure and parameters and show that the trajectory of duckbilled planter meets the agronomic requirements of vegetable cultivation.
Research on Characteristics of Spacecraft Transport Dynamics Ambient Excitation Based on Conditions of Highway and Railway Transportation
Authors: Guangtong Liu , Xukai  , Guotao  , Qiang Zhang 
Published: November 2019

Abstract
Based on the highway and railway transportation conditions of several spacecraft from Beijing to launch site, the dynamics environment data acquisition scheme is designed. The response values of sensors before vibration reduction of transport packaging box are collected throughout the whole process. The power spectral density is obtained by filtering and Fourier transform, and the peak response frequency of the excitation source of spacecraft transportation environment is analyzed. It can be used as the basis for the design of vibration reduction system for spacecraft transportation, and some suggestions for the optimization design of vibration reduction system are put forward.
Investigation of Blocking Effect of Aviation High-Speed Towing Tank Based on CFD and EFD
Authors: Xiao Zhijian , Jiang Rong , Wu Bin , Wang Mingzhen , Yang Wenjing 
Published: November 2019

Abstract
Taking the unpowered model of a seaplane as the object, the blocking effect of aviation high-speed tank was studied by experimental and numerical methods in this paper. Firstly, the experiment of air field and drag were carried out in the bottom and front of the trailer. The experimental results of air field showed that the blocking effect of the air field was obvious in the bottom of trailer, while ignored in the front of trailer. The results of drag experiment under two conditions showed significant difference at mid-high speed, which proved the influence of blocking effect was obviouse. RANS method and overset grid were adopted in numerical simulation, and the accuracy of numerical method adopted in this paper was verified by comparing computed results of the model in the bottom of trailer with the experimental results. The computed results of hydrodynamic performance of the seaplane in finite and infinite domain showed that the influnence of the blocking effect of water could be nearly ignored, but the influnence of the blocking effect of air field was dominated. Finally, the hydrodynamic performance of the seaplane under the trailers with different sizes of chassis were carried out. The computed results showed that within the certain range, the degree of blocking effect of air field increased with the increase of geometrical variables of trailer chassis, further, which reached the maximum and kept constant when the variables exceeded a certain value.
Study on Axial Parameters of Stepped Ferrofluid Seals
Authors: Wang Guohong , Yang Xiaolong , Zhang Ruibo 
Published: November 2019

Abstract
As a new type of intelligent material seal technology, ferrofluid seal has been widely used in high speed, heavy load and large eccentricity occasions in recent years because of its long life, low leakage and high pressure resistance. Because of the limitation of the axial height of the axis, most of the existing studies are focused on the radial parameters, but the specific research on the axial parameters has not yet been carried out. In this study, the theoretical pressure capabilities of height of the distribution of axial teeth and axial slot width was calculated according to the theory of stepped ferrofluid seals by finite element method. And by changing the radial gap, the stepped ferrofluid seal is compared with the ordinary seal, and the calculation results are analysed and discussed. The results show that the distribution mode of the axial teeth has a great influence on the theoretical sealing pressure resistance. And the theoretical sealing pressure resistance reaches the maximum when the distribution mode is evenly distributed. The influence of the width of the axial slot on the theoretical sealing pressure resistance can be neglected, so the technological property and the design should be considered as far as possible. By comparing the stepped seal with the ordinary seal, the practicability of the stepped seal is further verified.
An End-to-End Named Entity Recognition Model for Chinese
Authors: Gong Cheng , Tang Jiuyang , Li Zhen 
Published: November 2019

Abstract
Named entity recognition is an important basic task in natural language processing. This paper proposes a named entity recognition method for end-to-end and efficient deep-loop neural networks. Using BERT to train sub-vectors as raw input enables the model to obtain more comprehensive text information, and at the same time, the BiLSTM network is focused on the attention mechanism, so that the network pays more attention to the key information in the text and ignores the redundant information to improve the recognition efficiency of the model. Finally, the relationship between any two tags is captured by the CRF layer, and the entire sentence is decoded and predicted. Experiments show that the method performs well on MSRA corpus.