bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis and Evalution of Enteric Aqueous Polymethacrylate Coating Material
Authors: Chen Xiao Qi , Liu Chao , Zhou Hai Jun , Zhang Xiao Lei , Wang Fei , Li Yan Tao
Published: December 2013

A kind of enteric-coated pharmaceutical coating material, which can be dissolved in pH>5.5 medium, was successfully prepared by pre-emulsionsemi-continuous polymerization methods with equal molecular mass of methacrylic acid and ethyl acrylate as main raw materials. The effects of the initiator and chain transfer agent on the molecular weight and the performance of the emulsion were discussed. The obtained compound was used as the coating material of Lansoprazole capsule, and the dissolution rate was measured. The results show that polymethacrylat emulsion with 1.83×105 of molecular weight was obtained when the dosage of the initiator and the chain transfer agent is 0.43% and 0.79% of the total monomer mass, respectively. The dissolution rate of Lansoprazole capsule coated polymethacrylat emulsion in the pH 6.8 medium was greater than 75%.
Industrial Cluster Development and Social Responsibility: From Circular Theory Perspective
Authors: Cui Yu , Jiao Hao
Published: December 2013

From the perspective of the circular economy, the paper considers that the enterprise social responsibility in industrial cluster can be divided into four kinds of social responsibility of consciousness including the legal responsibility, moral responsibility, strategic social responsibility and charitable social responsibility. Moreover, the network behavior of social responsibility of enterprises with interaction is rooted in the enterprise. Finally, the interaction structure among cluster enterprises affects corporate social responsibility behavior choice and social responsibility behavior such as the production of the network, which can promote the information flow of enterprise social responsibility between suppliers, manufacturers and retailers.
Features Linear Fusion Based on AP Clustering and AASC Algorithm
Authors: Li Li Min , Wang Zhong Sheng
Published: December 2013

In the field of mechanical fault diagnosis, in order to improve the diagnosis accuracy with high feature dimension, a method of features linear fusion method based on AP(Affinity propagation clustering) and AASC(Affinity Aggregation for Spectral Clustering) algorithm was proposed. Low dimension space was obtained by AP clustering, then using AASC algorithm to fuse this selected features, and gained a new feature, meanwhile which can be used independently as a new feature. In the phase of experiment, this method was compared with respectively LPP and PCA, it’s result indicates that this method is excellent in improving diagnosis accuracy.
Research on Cooperative Scheduling and Design of Emergency Command System of Integrated Transport Hub
Authors: Gong Xiao Mei
Published: December 2013

Integrated transport hub as an important node of urban public transport system, in this paper, in accordance with the need of Integrated transport hub emergency management, based on the concept of public safety priority, the system composition and functional features to conduct a comprehensive analysis of the function, details of the integrated transport hub cooperative scheduling with the goal of building emergency command system, the system function structure, function modules of the logical relationship. The system research to establish integrated transport hub system scheduling and emergency command system has guiding significance and promotion value.
A Novel H-Phosphonate Method for the Synthesis of D-Mannose-1-Phosphate
Authors: Li Xing Jian , Gong Shan Shan , Sun Qi
Published: December 2013

A novel and efficient method for the preparation of α-D-mannose-1-phosphate has been developed. Phosphitylation of tetraacetylated D-mannose, hydrolysis yielded H-phosphonate monoester. Silylation of H-phosphonate, followed by oxidative coupling and hydrolysis gave protected D-mannose-1-phosphate. Finally, deprotection of tetraacetylated D-mannose-1-phosphate afforded D-mannose-1-phosphate in excellent yield.
Verification of Deformation and Loading of a Mould during Manipulation
Authors: Lufinka Aleš , Potěšil Antonín
Published: December 2013

One of the fabrication methods of artificial leathers in the automotive industry is the so called slush" technology. It is based on the powder sintering in a mould. The mould is loaded thermally during the production cycle and mechanically when manipulated. As cracks had occurred in the mould it was necessary to verify whether the cause of the crack initiation was thermal or mechanical loading. The aim of the first stage of the verification was the theoretical computation and measurement of the real mould loading during the manipulation. The paper describes the methods of computation and measurement.
The Numerical Analysis of Influence of the Shape of the Anchor Head on the Headed Stud's Tensile Capacity
Authors: Fornůsek Jindrich , Konvalinka Petr
Published: December 2013

This paper deals with the numerical analysis of the headed stud ́s tensile behavior in dependence on the shape and size of the head. Forty-eight 2D axi-symmetric numerical models were carried out. Three different embedment depths (50, 150 and 450 mm), each with four different angles of the top head surface (0, 20, 40 and 60 degrees) and four different head sizes (dh/hef = 0,15; 0,2; 0,3 or 0,4). The concrete behavior was simulated by the Nonlinear Cementitious2 fracture-plastic material model. The results of the analysis showed that the shape (angle) has only the negligible effect on the tensile capacity especially for the small heads. The more significant increase of the capacity was observed within the large head size where the increase of the bearing area due to the different angle is more significant.
Determine Parameters for Double-K Model at Three-Point Bending by Application of Acoustic Emission Method
Authors: Pazdera Lubos , Topolář Libor , Šimonová Hana , Fojtu Pavel , Smutny Jaroslav , Havlíková Ivana , Keršner Zbyněk , Rodriguezova Veronika
Published: December 2013

As concrete is one of the most popular building materials, it is important to know its basic properties and behaviour especially at loading. When cracks occur in concrete, released fracture energy will be proportionally transformed into the energy contained in acoustic emission. According to this physical phenomenon, acoustic emission technique provides an effective monitoring method for fracture process of concrete through generated acoustic emission. However, such monitoring is limited in qualitative evaluation of fracture process in most occasions. Quantitative interpretation of fracture process is difficult to accomplish by simply acquiring the amount of acoustic emission generated or by conducting parameter-based acoustic emission analysis. This paper investigates the use of the double-K fracture model and acoustic emission for prediction of load at the beginning of stable crack propagation in three-point bending tests of concrete specimens. Double-K model combines the concept of cohesive forces acting on the effective crack increment with a criterion based on the stress intensity factor.
Numerical and Experimental Research of Design Optimization of Baths for the Production of Nanofibers by the Electrospinning
Authors: Petrů Michal , Novák Ondřej , Ševčík Ladislav , Lepšík Petr
Published: December 2013

A study and analysis showed that the increase in production and the quantity of nanofibers obtained from electrospinning may be provided by not only increasing the potential gradient between the electrodes, but also by the suitable distribution of the intensity of the electrostatic field. Through a numerical simulation using the finite element method, it was found that the intensity distribution of the electrostatic field is influenced not only by the potential gradient, type and shape of the electrodes, polymer properties and its concentration, humidity, ambient temperature, but also by other parameters, such as relative permittivity of the material and shape of the construction geometry. Experiments have been done with the functional baths for polymer solution deposition with a different geometry and relative permittivity. By using the proposed changes in design and relative permittivity for the experiment with the polymer PVP with TiO2at 23.2 ± 3 °C and humidity of 14.4 ± 3 % and a potential gradient of 60 kV, the production of nanofibers can be increased by about 50 ± 3%. Key words: Electrospinning, optimization, nanofibers, FEM, reservoir
Analysis and Measurement of the Charge Intensity of the Selected Electrospinning Electrodes
Authors: Petrů Michal , Novák Ondřej , Lepšík Petr
Published: December 2013

Polymer solutions due to their chemical and physical properties requires for efficient spinning with different intensity of the charge. This corresponds to the geometry of the design of the spinning electrode. The electrode may have geometry in the shape of a smooth cylinder to obtain a less intense charge. Contrary barbed roll or roll with strings produces locally extremely intensive charge. For selected geometry of electrodes FEM models describing the intensity and the potential of the electrostatic field have been established and the results were compared with the experimentally determined results. From a comparison of the results it is evident that on the basis of the FE model can be formed with a certain accuracy to design suitably shaped electrodes to obtain the most efficient process of production of nanofibers. Key words: Electrodes, electrospinning, charge, intensity, FEM
New Specimen for Determination of the State of Plane Stress
Authors: Goga Vladimir
Published: December 2013

This paper presents new design of the structural specimen for plane stress analysis. Requirement was that the specimen is loaded by universal tensile testing machine without any special equipment. Specimen was analyzed using finite element method in ANSYS Workbench software. Finite element method was also used for simulation of strain gauge measurement to determine principal stresses, equivalent von Mises stress and orientation of the principal axes in the center of specimen. Finally, experimental stress analysis using strain gauges was performed on real specimen. Results from experimental measurements and numerical simulations were compared.
Mechanical Response of the Cross-Linked Pericardial Tissue
Authors: Gultova Eva , Horny Lukas , Chlup Hynek , Filová Elena , Staňková L'ubica , Pirk Jan , Bačáková Lucie , Žitný Rudolf
Published: December 2013

The significance of studying of human pericardial mechanics arises from a wide range of possible applications. For instance, tissue engineers study potential use of a human pericardium in a design of homograft valve bioprosthesis. In cooperation with the Institute of the Physiology of Academy of Sciences of the Czech Republic, human pericardium tissue has been modified by different cross-linking agents. The function and performance of the potential future bioprostheses depends closely on sources material. Thus characterization of the mechanical properties of the human pericardial tissue is an important problem. Several samples of pericardial tissue as well as cross-linked tissue underwent uniaxial loading and unloading. Their nonlinear mechanical response was modeled using hyperelastic theory, assuming incompressible isotropic deformation. Considering future possible tissue application, mechanical properties of the material under stress corresponding to the loading in aortic valve were evaluated.
Turbine Blade Loading and Experimental Verification
Authors: Doubrava Karel , Kuželka Jiří
Published: December 2013

The paper describes process of verification of FEM model of turbine rotor blade fatigue tests. Design of new turbine blade is tested on experimental stand, where load situation is similar to load of rotor blade of steam turbine during operation. Real load of blade and boundary condition on experimental stand was monitored by means of strain gauges set. Experimental data were compared with the computed results of several FEM models.
Study of Residual Stress Surface Distribution on Laser Welded Steel Sheets
Authors: Pala Zdenek , Kolařík Kamil , Ganev Nikolaj , Čapek Jiří
Published: December 2013

Advent of high power diode laser has substantially contributed to the popularity of laser welding in industry where its virtues such as low heat input and good weld strength are highly appreciated. However, one of the drawbacks of the laser welding is distortion of the welded bodies that is closely linked with the generation and/or redistribution of residual stresses in the vicinity of the weld. In this contribution, mapping of surface macroscopic residual stresses in two directions, i.e. parallel and perpendicular to the welds, were performed for two bodies. The first contained a weld created with the high power diode laser beam speed of 2 m/min and the second with the speed of 15 m/min. Our aim was to compare not only resulting fields of residual stresses, but also to perform qualitative assessment of the possible presence of crystallographic texture and gain a qualitative apprehension about the grain sizes in the vicinity of a laser weld joining two steel sheets. Larger distortion of the body with a laser weld is exhibited by the sample manufactured with approximately 8 times bigger speed of laser beam. This sample is in the immediate vicinity characterized by substantial compressive residual stresses in the direction perpendicular to the weld.
Experimental Investigation of Projectile Impact Local Damage on Cementitious Composite Slabs
Authors: Vavřiník Tomáš , Zatloukal Jan
Published: December 2013

This paper describes the projectile impact resistance of cement based composite slabs. The resistance is evaluated on the basis of the presented experimental program. In the experiment, local damage was inflicted by impact of defined projectiles on specimens made from normal strength concrete (NSC), steel fiber-reinforced concrete (FRC), ultra-high performance concrete (UHPC) and ultra-high performance fiber-reinforced concrete (UHPFRC) with different fiber content. Deformable ogive-nose projectiles with diameter of 7.92 mm and mass of 8.04 g with impact velocity about 700 m/s were in the experiment hitting center of the specimens. Data from the measured and visual evaluation of specimen damage were used for comparison of specimen projectile impact resistance in relation to the used material.
Experimental Testing of a Bridge
Authors: Melcer Jozef
Published: December 2013

The paper is dedicated to describing of experimental processes and experimental technique needed for realization of experimental tests of a bridge. The dynamic loading test was carried out on the monitored bridge. The time courses of bridge vertical displacements were registered. The power spectral densities of obtained records were used for determination of the basic natural frequency. The experimentally obtained results were compared with numerically obtained ones
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Memorization and other Transient Effects of ST52 Steel and its FE Description
Authors: Halama Radim , Fojtik Frantisek , Markopoulos Aleksandros
Published: December 2013

This contribution presents main results of experimental tests realized on smooth specimens made of ST52 steel under strain controlled uniaxial cyclic loading and compares these results with numerical simulations performed using a modified Chaboche model by finite element method. The effects of NonMasings behavior, memorization, cyclic hardening/softening and mean stress relaxation have been studied at room temperature. The experiments were realized on the reconstructed hydraulic fatigue testing machine INOVA 100 at the Laboratory of modern materials testing and defectoscopy of VŠB-TU Ostrava. Developed mixed hardening material model includes a memory surface stated in stress-space, which makes possible to significantly improve prediction of effects studied.
Wear Behavior of Hard Dental Tissues and Restorative Materials
Authors: Ctvrtlik Radim , Tomastik Jan
Published: December 2013

Human teeth are exposed to various chemical and mechanical factors. From mechanical point of view it includes attrition, abrasion or their combination. Teeth and dental restorative materials are subjected to normal and shear loads. Therefore the contact-based stresses during mastication and teeth wear are of considerable importance. In order to study wear behavior of enamel, dentine and two dental restorative composite materials scratch test at various contact conditions was employed. Hardness and elastic modulus were measured using nanoindentation with spherical and pyramidal indenters. Residual wear tracks were observed using laser scanning confocal microscopy.
Non-Destructive Inspection of Surface Integrity in Milled Turbine Blades of Inconel 738LC
Authors: Kolařík Kamil , Pala Zdenek , Beranek Libor , Čapek Jiří , Vyskocil Zdenek , Ganev Nikolaj
Published: December 2013

Nickel super-alloys are widely used in aerospace as material for turbine blades. Unfortunately, their machining is difficult since mechanical hardening and, consequently, extreme tool wear occur. Casting can no longer meet the requirements for precision, hence, the castings are being ground or milled. In this contribution, a quality check of the milled surface by several surface integrity parameters is proposed with respect to the surface structural inhomogeneities caused by mutual effect of plastic deformations and thermal fields during the cutting process. Castings from Inconel 738LC were milled with cutting conditions chosen by Design-Of-Experiments method and the resulting surfaces were assessed by non-destructive X-ray diffraction methods in several areas corresponding to various cutter orientation and work-piece angle. Surface integrity was described by macroscopic residual stresses, microstrains, grain sizes and phase composition. Mostly, favourable compressive surface residual stresses were observed in the cutting direction, grain sizes were distinctively smaller when the tool axis was perpendicular to the machined surface.
Sustainability Considerations for PCC Pavement Design and Construction
Authors: Chen Liang Liang , Zollinger Dan G. , Tian Bo
Published: December 2013

This paper addresses key issues regarding important factors affecting the sustainability and long-term performance of Portland cement concrete (PCC) pavement structures. Key distress types and their associated features are discussed in terms of their effect on performance and sustainability in terms of specific pavement components. Relevant material properties are also identified and discussed as to how they are represented in laboratory and field testing. A process to manage inspection resources is described and illustrated with the aid of a sustainability worksheet. This paper does not represent a guide or a standard for design or analysis.
Experimental Study on the Performance of Bond-Breaking Layer in Reducing Friction and Improving Anti-Erosion
Authors: Yao Jia Liang , Liu Xiang Long , Feng Ke Ke
Published: December 2013

This research explored the variation of bond-breaking effect with variety of bond-breaking layers installed between the concrete pavement surface slabs and the lean concrete (LCB) base, in order to offer parameters for structure analysis of pavements with bond-breaking layers and to optimize the selection of bond-breaking layers for the practical road engineering projects. This research tested the bonding stresses and the frictional forces at slab-base interface of pavements under different bond-breaking condition, as well as the anti-erosion performance of base course, via the anti-erosion tests in laboratory and the field tests for mechanical performance of slab-base interface treated with different bond-breaking layers in some highway projects of Hunan and Guangdong Provinces. Bond-breaking media applied in this research include the 3cm asphalt concrete (AC), 1cm emulsified asphalt slurry seal (EASS), geotextile and emulsion wax curing agent (EWCA). The findings from the field tests for bonding stress between slab-base layers indicated that EASS and EWCA did better than geotextile in reducing friction or bonding stress between slab-base layers. And the findings from the anti-erosion tests indicated that: under the same conditions, specimens covered with geotextile did far better than specimens brushed with asphalt on the surface in resisting erosion, and specimens covered with geotextile or brushed with asphalt did far better than no bond-breaking layer in resisting erosion. The mechanical performance of slab-base interface with different bond-breaking media derived from this research offers scientific reference to pavement design and construction control in the practical road engineering projects.
Key words: Mechanical performance of slab-base interface; Tests for bonding stress and anti-erosion tests; Bond-breaking layer of cement concrete pavement; Lean concrete base;Cement stabilized macadam base course.
Stress Analysis for Cement Concrete around Joint Dowel after Loosing
Authors: Hou Rong Guo , Niu Kai Min
Published: December 2013

The stress concentration will appear in cement concrete around joint dowel set in contraction joint of cement concrete pavement with repeated loads. And concrete around joint dowel will damage gradually.In this paper, the stress of concrete around joint dowel and deflection of concrete slab are analyzed when joint dowel loosing. It is indicated that the shear stress is key to damage of concrete around joint dowel. when the loosing width reaches certain extent. With loosing width increasing, load transfer capacity will decrease gradually. And it is shown that the load transfer capability will lower rapidly when the loosing width comes in 4cm.
Study on Test Methods for Intelligence-Based Monitoring of Fresh Cement Concrete Quality
Authors: Hou Zi Yi , Peng Peng , Xie Jin De , Zheng Shao Peng , Yuan Ye Zhen
Published: December 2013

A test method for monitoring of cement mortar quality has been devised and an empirical relational equation between cement mortar fluidity and torque has been worked out. A test method for monitoring of indoor fresh cement concrete quality has been devised and a relational equation between fresh cement concrete and torque has been worked out. A test method for monitoring of fresh cement concrete in a mixing plant has been devised and a relational equation between fresh cement concrete and current property has been worked out. By means of online observed torque and current data, relevant fluidity and slump can be predicted to provide test methods and relevant theoretical basis for intelligent monitoring of fresh cement mortar and cement concrete quality in actual engineering.
Study on the Effect of Different Admixtures on the Early Autogenous Shrinkage of High Performance Concrete of Bridge Deck Pavement
Authors: Li Xiang Qian , Tian Bo , Liu Wei , Su She
Published: December 2013

This paper analyzed the mechanism of early autogenous shrinkage of concrete, and studied the influence of early autogenous shrinkage of high performance concrete-(HPC) admixed with different kinds of materials of bridge deck pavement. Four different concrete mixes were used: fiber, fiber plus expansive agent, fiber plus fly ash and fiber plus shrinkage-reducing agent. The result shows that the four different mixes can inhibit the autogenous shrinkage of HPC to a certain extent, the inhibitory effect of different mixes in the order of strong to weak is: fiber plus shrinkage-reducing agent, fiber plus fly ash, fiber plus expansive agent, and fiber itself. Furthermore, the inhibition mechanism of each mix was analyzed and a conclusion of mixture of fiber plus fly ash to be the best choice considered of economic and working performance is drawn as well.
Experimental Study on Effect of Recycled Asphalt Mixture Particles on Properties of Concrete
Authors: Li Na , Zhang Dong Sheng , Han Wei Wei , Shen Ai Qin
Published: December 2013

To study the effect of different dosage of recycled asphalt mixture particles on the performance of concrete, the mechanical characteristics, shrinkage performance and durability testing were performed, the results show that the compressive strength and flexural strength of concrete are decreased with the increase of dosage recycled asphalt mixture particles, while still meet the regulatory requirements; the capability of plastic shrinkage resistance can be improved by incorporated recycled asphalt mixture fine particles, yet slight effective on the temperature shrinkage; the durability of concrete changes as a result of incorporation of recycled asphalt mixture fine particles, the durability of concrete with a dosage of 20% is considered in the optimal state, so the recommended dosage is 20%.
Durability and Applications of Magnesium Phosphate Material for Rapid Repair of Pavements
Authors: Yang Quan Bing
Published: December 2013

This paper presents some research results on the durability of magnesium phosphate cement-based material, such as strength, coefficient of thermal expansion, drying shrinkage, corrosion protection, deicer-frost resistance, abrasive resistance and strength loss while soaking in water or 3%NaCl solution. Experimental results indicate that MPB materials possess high deicer-frost resistance, high abrasion resistance and high corrosion protection for reinforcing steel. In addition, the MPB materials have good compatibility and bond with old concrete, and very low drying shrinkage. However, for the MPB materials soaked in water or 3% NaCl solution for a long time, the strength loss occurs. Laboratory and field studies show that the MPB materials are suitable for rapid repair of concrete structures, especially pavements, airport runways, bridge decks and key municipal roads, etc.
Study on Hair Crack Rubblization of the Old Cement Concrete Pavement
Authors: Wu Chao Fan , Zhang Xin Wang , Ma Zhi Xin
Published: December 2013

The optimum overlay structure and the better regeneration of the old cement concrete pavement were analyzed by empirical method, which compared the merits and faults of crack-seat and rubblization with the better regeneration to the old cement concrete pavement, then the concept of hair-crack-rubblization (HCR) was put forward, specific parameter standard of HCR was calculated by mechanical method. According to the desired requirement of HCR the hair-crack-rubblization machine was produced by Xi’an Changda Highway Maintenance Technology Co., Ltd. After that concrete realizable control standards of HCR and the optimum overlay scheme were gotten by the construction condition, then the merits of high strength, stable plate, good water-resistant and so on after HCR of the old cement concrete pavement, which combines the merits of crack-seat and rubblization, were showed by the engineering application.
The Study on Vibration for Integral Reciprocating Compressors
Authors: Liu Jing Hua , Hu Gui Chuan
Published: December 2013

According to the integrate reciprocating compressors vibration problems occur in the process of operation, research the working principle of the unit, the incentive vibration element, establishes the physical model of the vibration excitation source. it is a guiding significance for the dynamic design, reform system, monitoring and operation management of the integrate reciprocating compressors.
Second-Order Convergence and Unconditional Stability on Crank-Nicolson Scheme for Burgers’ Equation
Authors: Zheng Quan , Fan Lei , Sun Guan Ying
Published: December 2013

In this paper, we study the numerical solution of one-dimensional Burgers equation with non-homogeneous Dirichlet boundary conditions. This nonlinear problem is converted into the linear heat equation with non-homogeneous Robin boundary conditions by Hopf-Cole transformation. The heat equation is discretized by Crank-Nicolson finite difference scheme, and the fourth-order difference schemes for the Robin conditions are combined with the Crank-Nicolson scheme at two endpoints. The proposed method is proved to be second-order convergent and unconditionally stable. The numerical example supports the theoretical results.
Carbide Tools with Nano-Dispersed Coating for High-Performance Cutting of Hard-to-Cut Materials
Authors: Vereschaka A.A. , Vereschaka A.S. , Anikeev A.I.
Published: December 2013

The problem of increasing performance of carbide too lin machining hard-to-machine materials has been studied. Composite material was developed comprising carbide with heat-resistant bond Co-Re, significantly increasing resistance of carbide to thermoplastic deformation, and nanodispersed multilayer composite coating, significantly reducing thermomechanical impact on cutting part of tool.Studies to find the performance of tool made of developed composite material in turning hardened steel40H and heat-resistant nickel alloy HN77TYUR have shown its superiority compared to commercial carbides with coatings of modern generation.Studies have found out practicability of using VRK-13 cobalt-rhenium carbides with reduced content of expensive rhenium from 9% (weight) Re to 6% (weight), and it is highly competitive by heat resistance with VRK-15 carbide and is significantly superior to it by its strength.Results of cutting properties research forultra-dispersed Re-added WC-Co-carbides with Ti-TiN-TiCrAlNnano-dispersed multilayer composite coating are presented at longitudinal turning of constructional steels and hard-to-machine alloys. It is shown that the combination of ultra-dispersedheat-resistant WC-(Co,Re)-carbides and wear-resistant Ti-TiN-TiCrAlN coatings increase cutting properties of tool in some times.
Multiscale Model of Shape Rolling Taking into Account the Microstructure Evolution - Schedule Design by Finite Element Method
Authors: Łach Łukasz , Svyetlichnyy Dmytro
Published: December 2013

The material properties are strongly depended on the microstructure. Recently, for modeling and prediction of microstructure evolution during the forming processes a cellular automata method is used. Combination of several methods in multiscale model allows to extend the possibilities of each method and obtain more reliable results, which are close to the real conditions. The objective of this study is development of multiscale model of microstructure evolution during the shape rolling process and use it for simulation of rolling of 5 mm round bars. Model uses for calculations the finite element (FEM) and cellular automata (CA) methods. Modeling consists of three stages: design of the shape rolling schedule with the definition of shape and sizes of grooves (FEM simulation of each pass, starting from the last pass), FEM modeling of shape rolling in the proper sequence of the passes, modeling of microstructure evolution by frontal cellular automata (FCA). Stages (especially the last two) can be repeated several times to optimize the technology in view of final microstructure. The paper presents the first stage of modeling, which includes design and selection of grooves scheme with used the finite element method. The last six passes were modeled. The rolling scheme obtained from the modeling in the next stage is simulated by FEM to obtain thermomechanical parameters of the process. Then, temperature, strain and strain rate distributions in bar cross-sections, rolling time and inter-pass time will be used as input data for modeling by FCA.
Three-Dimensional Hydrodynamic Lubrication Analysis of Cylinder Liner-Piston Ring
Authors: Zhang Shi Feng , Cao Shu Hua , Xu Jiu Jun
Published: December 2013

This paper constructs a three-dimensional transient hydrodynamic lubrication model for cylinder liner-piston ring based on the three-dimensional transient average Reynolds equation and asperity contact model. A computer program was written with FORTRAN to calculate hydrodynamic lubrication, in which the surface roughness, the variable viscosity effect and the deformation of the circumferential direction of the cylinder liner are taken into account. The film pressure distribution in different crank angle during the stroke, minimum film thickness and friction are computed and analyzed with this program. This three-dimensional transient hydrodynamic lubrication model provides a design basis for the friction analysis of cylinder liner-piston ring.
A Study on Analysis Method Considering Camber for the Carbody Deflection of the Urban Transit Vehicles
Authors: Chung Jong Duk , Pyun Jang Sik
Published: December 2013

The carbody structure of electric multiple unit (here in after EMU) shall be designed withstand the loading conditions without permanent deformation or any form of damage. And the carbody shall have a minimum design life of 25 years or more in Korea. Loading conditions have a longitudinal compressive force and a vertical load. Camber of the carbody is defined as its curved shape viewed in side elevation. Carbody camber shall be a smooth arc from end to end of the carbody and shall be measured from a datum line drawn between the intersections of the arc with the center lines of the carbody bolsters to a line tangent to the arc midway between bolsters. The carbody shall be built with positive camber such that camber shall remain positive with the carbody at maximum load and shall not bind due to deflection caused by variations of service load. To assess the strength and stiffness of the designed carbody, carbodys designer shall be demonstrated by a programme of finite element analysis and testing shall be carried out in accordance with Korean standard technical specifications. The carbody is manufactured by giving the slope of the deflection to be compensated strength and stiffness. The deflection is camber. So this study analyzes that how camber affects safety and durability of carbody according to the load conditions and revenue service on main-line. Methods and analytical model of carbody structure is introduced to demonstrate them.
A Design Method of Rain Test Device Based on Water Drop Motion Simulation
Authors: Zeng Hong Tao , Lin Lin Lin , Feng Cong , Xiao Zhi Huai
Published: December 2013

In order to measure the electric insulation performance of the electrical equipment in rainy weather, its essential to design a rain device to simulate different conditions of rainfall. In this paper, a motion model of raindrop sprayed by the rain device and differential equations describing its motion characteristics are built. Basing on the analysis of water drop motion, a set of simulation software is developed for the selection of rain test device and the analysis of test results. The software can simulate the water drops motion process from nozzle to test equipment, and the simulation results is almost the same with field test, so the simulation software provides the basis for the design of rain test device.
Virtual Geometrical Data Definition of Part with Unspecified Shape
Authors: Monková Katarína
Published: December 2013

The contribution deals with the geometrical data definition of part with unspecified variable radius by means of modern equipment and computer aid. There are described some problems that originate at the real part digitizing. The possibility of virtual 3D model creating is given due to the modern equipment so called scanners. After the sections of scanned model were created,their contours were interpolated or approximated by curves of Bezier and Spline type. The curves were covered with a coat surface created as a Pro/Engineering systems own element, so the geometrical data were readable also for CAM system area. The virtual model serves for the generating of CL data to make new part on NC/CNC machine. The manufacturing of the part with CNC machine utilization enables to increase the production efficiency and the part quality.
Crane Basic Boom Static Analysis Based on ANSYS
Authors: Lian Jie , Li Jia
Published: December 2013

This article studied the 13 m basic boom of SC50C hydraulic crawler crane, and made static analysis on crane basic boom by applying ANSYS, and obtains the stress distribution. Based on the features of the loads and structure of the crane basic boom, this paper sets up a finite element model of it, thus providing reference for the design and optimization of crane boom.
The Influence of Zn3(PO4)2:Mn - Luminophores Synthesis Conditions on their Surface and Luminescent Features
Authors: Minakova Tamara S. , Sychov Maxim М. , Bakhmetyev Vadim V. , Ereminа Nina S. , Bogdanov Sergey P. , Zyatikov Ilya A. , Minakova Ludmila Yu.
Published: December 2013

A technology, that allows production effective x-ray luminescent phosphors Zn3(PO4)2:Mn2+ with nanosized particles from the water solution by sol-gel method, and directional regulated their luminescence color from green to red was developed. X-ray intensity and spectra, phase structure, and surface properties of synthesized samples depending on the synthesis conditions was studied. The conditions of synthesis which allow to obtain the samples according to the demands for the luminophores of medical assignment were determined.
Prospects of Using Nanopowders as Flame Retardant Additives
Authors: Nazarenko Olga B. , Amelkovich Yulia A. , Ilyin Alexander P. , Sechin Alexander I.
Published: December 2013

The paper presents the results of the studies showing the possibility of using AlN nanopowders as flame retardant additives. The nanoscale powder of AlN was obtained by electrical explosion of wires. The concentration of AlN nanopowder incorporated in a polyethylene matrix was 0.1; 0.25; 0.75; 1.5 and 3 wt%. The incorporation of 0.1 wt% AlN in a polyethylene matrix causes a 5 °C increase in the temperature of the beginning of melting and a 10 °C increase in the temperature of the end of melting in comparison with source polyethylene. The significant rise of the onset temperature of the intensive weight loss from 360 °C for polyethylene up to 375 °C for the sample with 1.5 wt% AlN was observed. The effect of the AlN nanopowder additives on the structure and mechanical properties of the polyethylene samples was also investigated.
Microstructure Features of Aluminum Alloys Welded Joint Obtained by Friction Stir Welding
Authors: Sizova Olga , Shlyakhova Galina , Kolubaev Alexander , Kolubaev Evgeny A. , Psakhie Sergey Grigorievich , Rudenskii Gennadii , Chernyavsky Alexander G. , Lopota Vitalii
Published: December 2013

The paper presents a metallographic study of aluminum alloy welds produced by friction stir welding. The weld structure is described for two alloys: Al-Cu and Al-Mg. It is shown that friction stir welding provides a fine-grained structure of the weld. The phase composition of the weld metal for the studied alloys is defined. Differences in the structure and distribution of second-phase particles in the weld metal are shown. The weld zone of Al-Cu alloy consists of equal size grains, with intermetallic particles located along the grain boundaries. The weld structure of Al-Mg alloy is banded, with alternating layers consisting of different size grains.
Phase Composition and Defect Substructure of the Zirconia Nanopowder Modified by the Powerful Ultrasonic Assistance
Authors: Khasanov Oleg L. , Ivanov Yury F. , Dvilis Edgar S. , Tolkachev Oleg S.
Published: December 2013

Commercial nanopowder of the partially yttrium-stabilized zirconia (ZrO2+3 mol.% Y2O3) was treated by the non-cavitational powerful ultrasonic action (PUA). Influence of PUA on the microstructure and phase composition of the powder has been investigated by scanning and transmission electron microscopy. Investigated powder before and after PUA has polycrystalline structure. It was found that TZ-3YS particles after PU-treatment have tetragonal and cubic zirconia phases; some of the particles consist of a mixture of monoclinic, tetragonal and cubic phases, but these particles have substructure with random orientation of fragments.
Formation Hybrid Method of Multilayer Biocoatings, Based on PVD Technology
Authors: Tverdokhlebov Sergey Ivanovich , Shesterikov Evgeniy Viktorovich , Malchikhina Alena Igorevna
Published: December 2013

Hybrid method of obtaining calcium-phosphate coatings is presented in this article. Physical and chemical, mechanical and tribological hybrid coatings research makes it possible to determine the coatings formation modes satisfying medical and technical requirements. This multilayer coating consists of an oxide underlayer formed by gas thermal oxidation and calcium phosphate layer formed by RF magnetron sputtering at a frequency of 13.56 MHz. Experiments were carried out in different modes. Calcium-phosphate coatings formed in mixture of argon and oxygen at 1:1 ratio pressure of 0.3 Pa have the best physical and chemical, mechanical and tribological properties.
Research on High Strength Hypoeutectic Al-Si Alloy
Authors: Jia Ting Ting , Chen Guo Shi , Zhang Shuo , Wu Ming , Geng Hao Ran
Published: December 2013

In this study, hypoeutectic Al-Si casting alloy was investigated to obtain high strength, according to alloying of Cu Mg, refining of Al-5Ti-B master alloy, modifing of Re and T6 heat treatment. The experimental results show that the mechanical properties of the tested alloy reach peak when addition of Al-5Ti-1B alloy is 1.0% after heat treatment, especially the yield strength, correspondingly, microstructure distribution gets to the best state. When Al-5Ti-1B exceeds 1.0%, the mechanical properties descend gradually. The metallic compounds of Mg2Si phase, CuA12 phase and W phase precipitated along the grain boundary and strengthened dispersively can improve mechanical properties of the tested alloys. The yield strength of samples added 0.1% Re (La 50%, Ce 40%) increases slightly, simultaneously, the tensile strength and elongation decreases. After 0.1% Re, the mechanical properties get down.
Synthesis of CuO Flower-Nanostructure via the Hydrothermal Method
Authors: Fu Xiao Ming , Ren Jie
Published: December 2013

CuO flower-nanostructures are successfully synthesized with CuCl2 as copper source and Na2CO3 as auxiliary salt at 180 °C for 24 h via the simple hydrothermal method. The phase and the morphologies of the samples have been characterized and analyzed by XRD (X-ray diffraction) and SEM (Scanning electron microscope), respectively. XRD analysis shows that the phase of as obtained samples is CuO. SEM analysis confirms that the increase of the reaction temperature is propitious to synthesize CuO flower-nanostructures while the increase of the reaction time is not in favor of their synthesis. The influence of the increase of the auxiliary salt on the morphology of CuO flower-nanostructures is not remarkable. The mechanism of the formation of CuO flower-nanostructure is discussed.
Morphology Change in Cuprous Oxide Particle Synthesis with PVP: Effect of Reaction Temperature
Authors: Wang Cheng Dong , Wang Ji Qian
Published: December 2013

Cuprous oxides with different morphologies could be prepared by simply changing the reaction condition, such as the temperature. Here, we report the Cu2O morphological transforming from polyhedron to cube with the reaction temperature increasing from 35C to 65C. At lower temperature, the polyvinylpyrrolidone (PVP) working as a crystal modifier which decreases the surface energy of facets (111) and (110), thus these high energy facets appear in relative low temperature. Facets (111) and (110) gradually diminished along with temperature increasing, while facet (100) expanded. The morphology became into cube from polyhedron. Cu2O particles synthesized at 65C are larger than those at 35C. The UV-Vis extinction bands of the cuprous oxide synthesized in this research were red-shift with the increase of particle size.
Preparation and Characterization of γ-Fe2O3-ZnFe2O4 Composite Nanoparticles
Authors: Chen Long Long , Li Jun Ming , Gong Xiao Min , Li Jian
Published: December 2013

Using a chemically induced transition in an FeCl2 solution, γ-Fe2O3 nanoparticles can be prepared from an amorphous precursor composed of FeOOH and Mg (OH)2. Surface modification by adding ZnCl2 during liquid-phase synthesis was attempted. The magnetization, morphology, crystal structure, and chemical species of as-prepared samples were characterized by vibrating sample magnetometer (VSM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray energy-dispersive spectroscopy (EDX), and X-ray photoelectron spectroscopy (XPS). The experimental results showed that the surface of the γ-Fe2O3 nanoparticles can be modified by adding ZnCl2 to form composite nanoparticles with a γ-Fe2O3/ZnFe2O4 ferrite core coated with Zn (OH)2 and absorbed FeCl36H2O; this modification can be enhanced by additional NaOH.
The Hydrothermal Synthesis of ZrO2 Nanoparticles and their Optical Absorption Properties
Authors: Fu Xiao Ming
Published: December 2013

ZrO2 nanoparticles with a diameter range of less than 10 nm are successfully synthesized with zirconium nitrate as zirconium source and stronger ammonia water as precipitant at 210 °C for 48 h via the easy hydrothermal method. The phase, the morphologies and optical absorption properties of the samples have been characterized and analyzed by X-ray diffraction (XRD), field-emission transmission electron microscopy (TEM) and ultraviolet-visible absorption spectroscopy (UV-VIS), respectively. XRD analysis shows that the phase of as obtained samples is ZrO2. TEM analysis confirms that using stronger ammonia water as precipitant instead of NaOH and the increase of the reaction temperature are in favor of the synthesis of ZrO2 nanoparticles. And UV-VIS measurements show that ZrO2 nanoparticles have a good optical absorption property.
Memristive Behaviors in Ag2S Nano-Particles Assembly
Authors: Wu Hong Ya , Cai Kun Peng , Zhou Ji
Published: December 2013

A memristive phenomenon was observed in bulk silver sulfide (Ag2S) nanoparticles assembly, obtained by a chemical reaction method. Current-voltage characteristics of memristors, pinched hysteretic loops were systematically observed in the Ag/ Ag2S /Ag cell. According to the as-obtained stable bipolar IV plots, resistance ratio between high resistance state and low resistance state was measured to be almost 100. An electrochemical redox reaction of S on the interface between Ag electrode and Ag2S electrolyte was proposed to explain the mechanism of the experimental phenomena.
Galvanostatic Deposition of PT Nanoparticles on TiO2 Nanotube Arrays for Amperometric Detection of Hydrogen Peroxide at Low Overpotentials
Authors: Liu Jia Qin , Ruan Li Li , Xu Guang Qing , Lv Jun , Wu Yu Cheng
Published: December 2013

Highly ordered TiO2 nanotube arrays (NTAs) modified with Pt nanoparticles (Pt/TiO2 NTAs) have been prepared by anodization of Ti foils followed by electrochemical deposition and employed to improve the performance of the low-overpotential determination of H2O2 in solution. Morphologies of TiO2 and Pt/TiO2 NTAs were observed by SEM and TEM. The electrochemical behaviors of TiO2 and Pt/TiO2 NTAs were compared by cyclic voltammograms (CVs) in phosphate buffer solutions in absence and prensence of 10 mM H2O2, which showed that Pt nanoparticles can enhance the electrochemical activities of TiO2 NTAs and achieve low-overpotential determination of H2O2. Amperometric method with an applied potential of-100 mV was used for H2O2 detemination, which demonstrated a good H2O2 sensing with sensitivity of 5.4 μAcm-2mM-1.
Controlled Synthesis LaPO4 Nanorods via a Hydrothermal Route
Authors: Dai Jie , Liu Kai Li , Li Xia
Published: December 2013

LaPO4 nanorods have been selectively synthesized via a hydrothermal route, using La (NO3)3·6H2O and NaH2PO4 as raw materials, without using any catalyst or template. X-ray diffraction (XRD), scanning electron microscopy (SEM), IR spectra (IR) and photo-luminescence (PL) spectra were used to characterize the as-prepared samples. The morphological changes of the products due to the different mole ratios of La (NO3)3·6H2O and NaH2PO4 were studied. The effect of the thermal treatment on the structure of the LaPO4 nanorods was also investigated. In addition, the emission intensity of LaPO4 nanorods with different Eu doped concentration was compared and discussed.