bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reinforcement of Notched PBX Simulant Beams with CFRP Patches-Experimental Study
Authors: Wang Shengnan , Tang Mingfeng , Zhou Hongping 
Published: March 2020

Abstract
Strength degradation induced by geometrical discontinuities is a primary cause of structural failure for polymer bonded explosive (PBX). To restore structural integrity and extend service life, reinforcement of weakened PBX structures is urgently demanded. In the present work, carbon fiber reinforced polymer (CFRP) patches are employed to notched PBX simulant beams. By using digital image correlation (DIC) technique, the influences of CFRP patches on mechanical behavior of the beams under bending load are explored. Results show that the CFRP patches endows the beams with increased strength and stiffness. Due to the load-sharing and deformation-confining of the patches, stress concentration at the notch is relieved, and crack propagation in PBX simulant matrix is prevented. These discoveries may provide important enlightment for the reinforcement and repair of the weakened PBX structures, and in addition, provide basis to the potential application of CFRP patches in energetic materials.
Structure Solution of ACV-GLU Cocrystal by Combined XRD Refinement, 1D Solid State NMR and DFT Calculations
Authors: Li Ping , Liang Tingting , Liu Huan , Guo Jixin , Chu Jingjing , Qiu Lingfang , Duo Shuwang 
Published: March 2020

Abstract
The powder sample of ACV-GLU crystal complex was prepared by formic acid-assisted grinding. 13C and 15N chemical shifts were assigned by referring to the 1D NMR spectra of raw individual components. The crystal structure was first solved by Rietveld refinement. The calculated NMR parameters were compared with the experimental results to validate the proposed structure. ACV, an important antiviral drug, can be cocrystallized with GLU into a triclinic unit cell with a molar ratio of 1:1 where each unit cell consists of two ACV molecules and two GLU molecules. Six intermolecular hydrogen-bonding interactions exist in the cocrystal. An agreement between experimental and calculated NMR parameters would give a final confirmation of the correct model among the preliminary candidates. Such synergistic approach provides efficient and convincing method to obtain the crystal structure of powder cocrystal specimens.
Novel Dopant for Conductive Polymers: Spherical Polyelectrolyte Brushes
Authors: Su Na 
Published: March 2020

Abstract
Conductive polymers with special structure and excellent physical and chemical properties, have become a research focus in materials science since the first discovery in 1977. While a growing body of work in recent years has concentrated on the improvement of the electrical conductivity of conductive polymers by using doping technique. The spherical polyelectrolyte brushes (SPB) consisting of polyelectrolyte chains grafted densely to the surface of the core particles, have shown great promise of novel dopant for conductive polymers due to its spherical structure, high charge density and high grafting density. After summarizing the researches of the general dopant for conductive polymers, this review mainly emphasizes on the preparation, doping mechanism and advance prospect of conductive polymers doped with spherical polyelectrolyte brushes.
Synthesis, Structure and Magnetic Property of a Tricapped Trigonal Prismatic TbIII-Based 3d-4f Complex
Authors: Zhuang Jia-Jia , Chen Ming-Guang , Sun Yan-Bing , Hang Pei , Sui Yang , Tong Jia-Ping 
Published: March 2020

Abstract
A novel 3d-4f CoII/TbIII cluster [Co6Tb(Pic)6O3Cl3](H2O)6 (1) (Pic = 2-Picolinic acid) has been synthesized and characterized via X-ray crystallographic and magnetic measurements. X-ray crystallographic and continued shape measurements analysis revealed that the central Terbium (III) is coordinated in TbO9 geometry with D
3h
symmetry. Magnetic studies indicated the complex presents a magnetic anisotropy with ferrimagnetic interactions.
Thermal Shock Behavior of Polymer Bonded Explosive below and above the Viscous Flow Transition Temperature
Authors: Tang Mingfeng , Wang Shengnan , Li Ming 
Published: March 2020

Abstract
The effect of initial cooling temperatures on the thermal shock behavior of cylindrical polymer bonded explosive (PBX) was investigated by using a combined acoustic emission (AE) and strain gauge technique in fast air-cooling tests. Dissimilarity was observed below and above the viscous flow temperature (Tf) where the PBX exhibited brittle-ductile transition and temperature dependence on material properties. We found that cooling below Tf would lead to fracture with strong AE signals and a linear strain-time response followed by a sharply decline, while above Tf would generate weaker AE events and a non-linear strain history with soften response. A segmented characterization was proposed for the calculation of thermal shock resistance and the corresponding critical fracture temperature difference. This estimation fits well with our experimental and simulation results.
Experimental Study on Mechanical Properties of Fiber Composite Material Adhesion to Metal
Authors: Li Qinghua , Jiao Yuxin , Zhang Yan , Tian Ranran , Zeng Yu 
Published: March 2020

Abstract
The fiber composites were impregnated at different times and bonded to metal materials; the mechanical properties of the bonded composites were measured. In this article, two kinds of materials, the carbon fiber fabric and the Kevlar fiber fabric, were compounded with epoxy resin E51 to form the fiber fabric composite material. The composite material was bonded to the surface of 45 steel by modified epoxy resin adhesive. The bond strength of composites were measured by the tensile method of determination of the bond strength between vulcanized rubber and metal, the shear strength of composites were measured by Four-plate shear method of determination of the bond strength of vulcanized rubber and rigid metal sheets by the international standard ISO 1747-1976, to obtain the maximum bond strength and shear strength of the composite material, and the corresponding optimum immersion time of the carbon fiber fabric.
Electrodeposition Assisted Dynamic Assemblies of Chitosan/Alginate Composite Multi-Membrane
Authors: Xu Feiyang , Wang Dong , Yan Kun 
Published: March 2020

Abstract
Electrodeposition of natural polymer as an effective approach to improve bioactivity of the conductive substrate has receives much attentions in medical and other applications. In this work, we developed a novel chitosan/alginate (CS/ALG) multi-membrane on titanium plate via the electrodeposition assisted dynamic assembly approach. Specifically, the electrical signal induced CS coating can serve as a versatile platform for layer by layer assemblies of ALG into the multi-membrane through strong electrostatic interaction. The prepared multi-membranes exhibit great swelling performance and excellent mechanical properties at dried states, with the tensile stress and strain values reaching to 58.2 MPa and 4.25 % for the 10 layers sample. In summary, we believe such green, low cost and rapid fabrication approach and mild processing environment would spur great potential for construction of multi-functional coating and smart drug elution system on the conductive implants.
Glass Transition and Stress-Strain Curve of Polyaspartic Ester Polyurea at Different Tension Condition
Authors: Zhang Jian , Zhai Junxue , Lin Jinjian , Du Aihua , Qingguo Wang , Zhao Xijuan 
Published: March 2020

Abstract
The tensile properties of polyurethane are related to the microstructure due to the change of hydrogen bond and hard segment domains at different temperature and velocity. In this paper, the structure and glass transition before and after tensile breakage of polyaspartate (PAE) based polyurea (PU) coatings were analyzed by Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC) and tensile strain energy of stress - strain curve. The PAE-PU has not changed its allophanoyl (C=O in urea) and amino (N-H) hydrogen bond content apparently by the comparison of their IR absorption peak height. The PAE-PU has two glass transition temperatures related to soft and hard segments, which move to greater distance after tension. Moreover, the Enthalpy relaxation accompanied by hard segment glass transition almost disappears after tensile break. The dependency of tensile curve of PAE-PU on tensile rate at the same temperature is different from ordinary polymer materials; i.e.it has greatest yielding, strength and strain energy at medial rate of 100mm/min rather than higher ones.
The Effects of the Recycled Polyethylene on the Properties of Special Material Blends for Pipe and Final Products
Authors: Sheng Li , Lu Xiaoying , Chi Liang , Xu Chunyan , Li Shuanhong 
Published: March 2020

Abstract
A detail comparison between recycled polyethylene (RPE) compounds and special material for pipe in respects of mechanical properties, antioxidant performance, metal contents and rheological behaviours was performed. The results showed that the MFR, the content of ash and typical metallic element of blends increased with the RPE component, while the OIT, fracture strain and impact strength tend to decrease. However, for those unused waste PE there’s no significant difference in most performance parameters compared with the new ones, especially when the RPE content was lower. In contrast, the content of typical metallic element such as Ferrum (Fe) and Calcium (Ca) can still be a crucial indicator for distinguishing the existence of RPE. Undoubtedly, the test of pipe products proved that the introduction of RPE caused the decrease of pressure resistance and resistance to slow cracking.
Infrared and Raman Spectral Analysis of the Polycrystalline Copper Hydroxonitrates
Authors: Fu Jianlong , Liu Xiaodong , Liu Lu , Meng Huamao , Wang Xinbo 
Published: March 2020

Abstract
Two kinds of vibration spectra (Mid-infrared and Raman) of the magnetic geometrical frustration compound copper hydroxonitrate (hydroxyl nitrate, or hydroxide nitrate, Cu2(OH)3NO3) polycrystalline powders, which were synthesized successfully by the hydrothermal and solid-state reaction methods, respectively, have been measured at room temperature and analyzed by referring to the assigning of the Gerhardtite (natural Cu2(OH)3NO3) and α/β/γ-Cu2(OH)3Cl. The result can give some help to analyze the quality of obtained related samples for the further low temperature spectral experiments, which can reveal the underlying physics of their exotic geometric frustration phenomena from the spectral viewpoint.
Influence of Solution Treatment on Microstructure and Electrical Conductivity of Wrought Al-15Si Alloy
Authors: Liu Fang , Jian Yongchao , Yu Fuxiao , Zhao Dazhi 
Published: March 2020

Abstract
In the present work, the microstructures and electrical conductivity of Al-15Si alloy in casting, extruding and solution treatment conditions were investigated. The results indicate that the extruded Al-15Si alloy has higher electrical conductivity. It has been revealed that the morphology of Si, iron element and grain boundary impact on electrical conductivity of the Al-Si alloy. With the revolution of the microstructure, these factors which lead to the changing electrical conductivity of the alloy are discussed in detail.
Optimization of Cooling System for Hot Forming Based on Orthogonal Experiment
Authors: Huang He 
Published: March 2020

Abstract
Taking the U-shaped part of 22MnB5 ultra-high-strength steel as an example, a finite element model of hot stamping is established. The temperature field distribution characteristics of the sheet during the hot forming process are analyzed by DEFORMV11.0 software combined with the orthogonal experimental design method. The diameter of the pipe, the distance from the pipe to the mold surface, and the distance between the pipe and the pipe will affect the temperature field of hot stamping. Then, the cooling system parameters is designed and optimized.
Effects of Different Atomization Method on Powder Property, Microstructure and Low Cycle Fatigue Property of FGH97 Alloy
Authors: Tan J J , Guo J Z , Long A P , Li Q T , Xiao L 
Published: March 2020

Abstract
Two kinds of Ni-based superalloy powders (P-powder and A-powder) were prepared from masteralloy melted via the process of vacuum induction melting (VIM) by plasma rotating electrode process (PREP) and argon atomization (AA) method, which were used to fabricate two different alloys (P-alloy and A-alloy) using the same hot isostatic pressing process and heat treatment process. The study of microstructure and mechanical properties of FGH97 alloy were conducted to demonstrate the effect of different routes of powders preparation on the microstructure and low-cycle fatigue properties. Results show that the particle size distribution of P-powder is narrower than A-powder, and overall is larger, and the size of the inclusions in the A-powder is much smaller than P-powder. And it has been found that the grain size of A-alloy is finer and γ’ phase is more uniform, compared with P-alloy, there is no residual dendrite, grain boundary carbides are intermittent punctate distribution; the strength of A-alloy is slightly higher, and the plasticity is better than P-alloy; at the same time, the crack initiation is formed at the site of slag inclusions, but the size of inclusions of A-alloy significantly smaller; accordingly, the resistance of low-cycle fatigue crack initiation of A-alloy is superior than that of P-alloy due to the fine powder prepared by the process of argon atomization, showing a life time of much more than 150 000 cycles, far better than P-alloy (<70000 cycles); and the fatigue property of A-alloy is very stable.
Contact Performance and Thermal Stability Improvement of Amorphous InGaZnO Thin-Film Transistors by Using a Buffer/Cu/Buffer Source/Drain Electrode Structure
Authors: Li Gongtan , Zhu Feng 
Published: March 2020

Abstract
This paper discussed the contact characteristics and thermal stability of a-IGZO TFT with various kinds of buffer/Cu/buffer electrode structure. The work found that the a-IGZO TFTs with Cu electrode and Mo/Cu/Mo electrode show worse thermal stability than these with ITO/Cu/ITO electrode. The work speculates that the contact performance deterioration after post-anneal was due to Cu oxidation and an interface separation between Mo and Cu, respectively. The work used the G-function method to discuss the contact performance of a-IGZO TFTs with the different kinds of S/D electrodes. The a-IGZO TFT with an ITO/Cu/ITO electrode shows a smaller contact resistance than the other TFTs and had an ohmic contact between the a-IGZO and ITO. In terms of thermal stability and contact performance, ITO/Cu/ITO electrode is a better choice than Mo/Cu/Mo electrode.
Feasibility of Evaluating Acoustoelastic Coefficient of Concrete under Tensile Stress with One-Sided Ultrasonic Method
Authors: Yang Yu , Zhang Shuo , Bao Ting , Wang Yi 
Published: March 2020

Abstract
In this paper, an experimental study on the feasibility of evaluating acoustoelastic coefficient of concrete with one-sided ultrasonic pulse method under tensile stress is conducted. Tensile load cycles are imposed on prismatic concrete specimens and ultrasonic wave velocities are measured simultaneously. Acoustoelastic coefficients are obtained by linear fit of the test results and compared to correlate results in literature. The feasibility of evaluating acoustoelastic coefficient of concrete with one-sided ultrasonic method under tensile stress is discussed.
Prediction of the Slump of Fly Ash Blended Concrete Based on Various Numerical Models
Authors: Wang Xiao-Yong 
Published: March 2020

Abstract
Slump is a fundamental engineering property of fly ash blended concrete. This study proposes various numerical models, such as multiple linear regression (MLR), artificial neural network (ANN), and genetic algorithm assisted artificial neural network (GA-ANN) for estimating the slump. First, the concrete slump is regressed as a multiple linear equation of water-to-binder ratio, water content, sand ratio, fly ash replacement ratio, air-entraining agent content, and superplasticizer contents. The correlation coefficient of the MLR method is 0.63. Second, the ANN model is set up, which consists of an input layer, a hidden layer, and output layer. Based on the backpropagation (BP) training method, the optimized network is found. The correlation coefficient between analysis results and experimental results of ANN model is 0.78. Third, GA is used to assist in the optimization process of ANN. The initial value of the hidden layer of ANN is generated by using a genetic algorithm (GA). The correlation coefficient of GAANN integrated model is 0.85. GA-ANN integrated model can make more accurate prediction results than MLR model and ANN model.
Application of High Stiffness Modulus Asphalt Mixture in Longitudinal Slope of Jiqing Expressway
Authors: Yang Weigang , Wang Xiaoyan , Liu Jiarong , Ma Shijie 
Published: March 2020

Abstract
In this paper, according to the French LCPC asphalt mixture design method, the high modulus asphalt mixture is designed. It is found that the designed high-stiffness modulus mixture has high water stability, high temperature resistance to rutting and fatigue performance. The high-speed and long-slope section was successfully promoted and applied, which solved the problem of the structure and material durability of the long-slope section of the expressway under heavy load conditions and prolonged the service life of the road.
Research on Calculation Method of Non-Road Mobile Machinery PEMS
Authors: Yong Li , Jian Ling , Ming Gao-Zhong 
Published: March 2020

Abstract
In this paper, four typical non-road mobile machinery test objects were used to test the actual operation of the machine’s NOx emissions using a portable emission measuring system (PEMS). The NTE method of the United States and the European work-based window method test data were used for processing and analysis of emissions. The research results show that the NTE method cannot be applied to the actual operation emission analysis of four non-road mobile machinery, and the work-based window method can accurately evaluate the emission levels of four non-road mobile machinery.
Experimental Study on High Performance Cement in Aeolian Sand Concrete
Authors: Yang Zhengxun , Tang Binpeng , Huo Zhiqiang 
Published: March 2020

Abstract
In order to alleviate the current shortage of river sand resources in China, the experimentation of producing C30 concrete utilizing the aeolian sand as fine aggregate was carried out, in this experimentation, high-performance cement was used instead of ordinary cement, the basic mechanical properties of aeolian sand concrete was tested after maintenance. The results show that the flexural strength of concrete with aeolian sand content of 30% is nearly 4 MPa, the compressive strength fits the standard requirement. The high-performance cement exhibits its superior cementation ability, and the application of aeolian sand in concrete is preliminarily realized.
Experimental Study and Analysis on Compressive and Tensile Behavior of Basalt Fibre Reinforced Concrete
Authors: Zhou Hao , Jia Bin , Huang Hui , Mou Yanling 
Published: March 2020

Abstract
Blending a certain proportion of basalt fiber into concrete improves the toughness of concrete, which enhances the tenacity and prevents cracking, thus avoiding the brittle behaviors of concrete. In this paper, the compressive and tensile tests of the concrete with different basalt fiber contents were carried out. Then, the test phenomena, failure modes, and mechanical properties were compared and analyzed to derive the relationship between the basalt fiber contents and the mechanical properties. The results showed that the improvement effect of the basalt fiber on the compressive strength of concrete was lower than that of tensile strength. When the basalt fiber content is 0.3% and 0.4%, the improvement effect was the highest. In the meanwhile, the correlation coefficient of the fiber physical and mechanical parameters and content was introduced to establish the calculation formula for the crack width of basalt fiber reinforced concrete. Finally, the toughness and crack resistance performance of basalt fiber concrete were evaluated by the fracture energy and characteristic length proposed by Hillerborg. The results showed that basalt fiber can significantly improve the toughness and crack resistance performance of concrete.
A Review on the Geopolymer Materials Used in Grouting Piles
Authors: Peng Shengjiang , Yang Dezhou , Wang Shijun , Ping Chang 
Published: March 2020

Abstract
Bored cast-in-place piles are often used in power transmission projects. However, common bored cast-in-place piles with mud wall protection had some shortcomings, such as complicated construction procedure, poor quality of concrete, low bearing capacity, and pollution caused by mud wall protection. In this paper, the construction technology, quality evaluation method and design calculation of the new technology of Continuous Flight Auger pile were summarized. In addition, this technology combining geopolymer high strength concrete material was proposed, and the application of this technology in power transmission projects was prospected.
Experimental and Numerical Investigation on Global Buckling of Q690 High Strength Steel Tubes under Axial Compression
Authors: Sun Shuchang , You Qiang , Gu Xin , Peng Yiliang 
Published: March 2020

Abstract
Due to the excellent bearing capacity, high-strength steel (yield stress ≥ 460 MPa) is gradually utilized in the design of super high-rise buildings, long-span bridges and other important structures to reduce section size and self-weight. In the present study, the axial compression test and numerical simulation were carried out to investigate the global buckling of high strength steel tubes. Eighteen specimens of Q690 high strength circular steel welded tubes were tested under axial compression to obtain the ultimate bearing capacity and buckling mode. An effective finite element numerical model incorporating the residual stress and geometric imperfection was established to analyse the influence of slenderness ratio, diameter thickness ratio and residual stress on the global stability coefficient. According to the calculation results, the column curve of Q690 circular steel tube was obtained and compared with three different codes. Finally, a formula to calculate the global stability coefficient of Q690 welded circular steel tubes was suggested.
Effect of Line Energy Density and Wall Thickness on the Top Surface Quality of AlSi10Mg Sample Fabricated via Selective Laser Melting
Authors: Dai Shimin , Zhu Haihong , Zeng Xiaoyan 
Published: March 2020

Abstract
The effect of line energy density (LED) and wall thickness on the top surface quality of AlSi10Mg sample fabricated by selective laser melting (SLM) has been investigated in this paper. It is observed that the surface morphology has great evolution which the molten track turns to regular and then to irregular with the increase in LED. The line roughness (Ra) and peak height (Rz) decrease first and then increase as the LED increases. The optimal LED for low Ra/Rz increases from 0.1389 J/mm to 0.30 J/mm with the wall thickness increases from 0.1 mm to 2 mm. This work can provide a guide of manufacturing complexy geometrical thin-walled parts with a fine top surface quality.