bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison of Various Techniques for Flexural Strengthening of Thin Concrete Members Using Continuous Carbon Fibers
Authors: Ivanič Andrej , Lubej Samo
Published: August 2015

This paper deals with flexural performance of thin concrete members reinforced with continuous carbon fibers in the form of filament yarns. The laboratory specimens were tested under static loading conditions to investigate the effects of three different strengthening techniques on flexural stress, mid-span deflection and modes of failure. The specimens were strengthened in flexure using carbon fiber yarns as near-surface mounted, externally bonded and placed in the geometric center of the specimen, respectively. Based on this investigation, the advantages and shortcomings of individually strengthening technique can be drawn.
Studies of High Temperature Performance of Asphalt Based on Repeated Creep and Recovery Test
Authors: Xu Hong Fei
Published: August 2015

The high temperature characteristic of asphalt is closely associated with the performance of asphalt pavement. In this paper, repeated creep and recovery experiments are conducted for 2 kinds of base asphalt and 4 different kinds of modified asphalt. According to the pavement situation of China, two temperature levels (i.e., 60 °C and 70 °C) and two stress levels (120Pa and 300Pa) are selected in the test. We observe improved performance of the modified asphalt than the base asphalt, owing to the fact that the modified asphalt is a linear viscoelastic material, with special delayed elastic deformation and recovery properties. The high temperature performance of the modified asphalt is vulnerable to changes in temperature, stress and loads. We further perform rutting test and find that result is highly correlated with the viscous composition of creep stiffness (Gv), with the correlation coefficient being 0.9838 and 0.9813, respectively, indicating that Gv can well judge the merits of high temperature performance of different asphalt.
Experimental Study on the Material and Environmental Property of Ancient Adobe Brick
Authors: Yuan Jian Li , Yang Yun , Peng Sheng Nan
Published: August 2015

Aiming at the environmental property and damage mechanism of ancient adobe buildings, the material components, compressive strength and freezing-thawing resisting performance of ancient adobe bricks were tested and analyzed. Based on test data, the power function relation between nondestructive rebound value and compressive strength of adobe bricks was established, and the nonlinear correlation curve between mass loss rate and freezing–thawing cycles of adobe bricks was also determined. The study shows that the compressive strength of ancient adobe brick is greater than that of adobe in traditional rammed earth wall, and ancient adobe brick is inferior to fired brick at the waterproofing quality and freezing resisting performance, it needs to adopt surface waterproofing measures for ancient adobe buildings to improve the resisting capacity to environmental erosion.
Centre of Panel Thermal Conductivity Performance Analysis of Aerocor-Centrifugal Hybrid Ultrafine Glass Fiber VIP Core Materials
Authors: Farooq Ahmad , Abd El-Aty Ali
Published: August 2015

This paper includes analysis on the recent advancement of glass fiber core based vacuum insulation panels (VIPs) in China, including the experimental development of mixed ultrafine fiberglass prototype core material consisting of Centrifugal and Aerocor glass wool mixture at different ratios. Pore sizes exhibited by these prototypes generally range between 15-25μm. Extensive centre of panel thermal conductivity (Kcop) were performed from which thermal performance graphs were extracted and analyzed prudently. Kcop analysis verified superior performance of the prototypes over traditional glass fiber core samples, hinting greater service life. The study concludes that in order to optimize the long term performance of current industrial glass fiber core material reduction of pore size at less than 10μm range as well as reduction of x-z axis fiber orientation angle to less than 450 would potentially decrease core structural sensitivity towards both gaseous and solid conductivity at increase of internal pressure.
Shape-Controlled Synthesis and Pattern Recognition of Core-Shell Co-Al Hydroxides Superstructures
Authors: He Peng Cheng , Ji Xiao Bo , Zhang Qing , Liu Yi Fei , Lu Wen Cong
Published: August 2015

In this paper, the optimal projection recognition (OPR) developed in our lab has been used to find the regularities of forming core-shell Co-Al Hydroxides superstructures.The criteria for predicting core-shell Co-Al Hydroxides superstructures can be obtained by using OPR method among different kinds of pattern recognition diagrams. The new samples predicted to be core-shell Co-Al Hydroxides superstructures were designed by using the inverse projection based on the OPR method. The predicted results agreed well with our experiments. Therefore, the work presented is very useful in the shape-controlled synthesis of core-shell Co-Al Hydroxides superstructures.
Application of Multifunctional Scouring Agent for Cotton Fabric Bleaching
Authors: Hamzah Mohammad Amir , Liu Fan , He Lin Wei , Cai Ying Jie , Zhang Ping
Published: August 2015

Multi-functional scouring agent (M.F.S.A.) successfully can replace caustic soda, soda ash, scouring agent and H2O2 –bleach stabilizer. It has strong properties of washing, dispersing, emulsifying and chelating, particularly applicable to bleach bath. In this experiment three processes like desizing, scouring and bleaching were done by single stage. Grey fabrics (woven) were treated by using various concentrations of M.F.S.A. and H2O2 at different temperature variation. The maximum value of whiteness of treated fabric were found at 80°C by using the concentration of M.F.S.A. and H2O2 (3.0 g/L and 3.0 g/L respectively). Also minimize required number of chemical used for bleaching process; here only two chemicals used for whole process. No additional chemicals used for water treatment and washing of treated fabric. After process only cold wash were done. Finally by using less concentration of both M.F.S.A. and H2O2 have got comparatively better result for whiteness and tensile strength.
Synthesis and Characterization of Poly(o-chloroaniline) Micro/Nanostructures in a Novel Redox System
Authors: Zhang Meng , Sun Dong Hao , Wang Ying
Published: August 2015

In a redox system containing ascorbic acid(AA) and ammonium persulfate(APS), Poly(o-chloroaniline)(POC) micro/nanostructures including nanoparticles, nanofibers, and microspheres were successfully prepared through a self-assembly process in absence of additional template. The results indicated that POC morphologies were strongly affected by the molar ratio of o-chloroaniline(OC) to ascorbic acid([OC]/[AA]) and the reaction temperature. The fibrillar or spherical POC micro/nanostructures could be dynamically controlled in the AA/APS redox system by changing the polymerization rate of OC monomers. Thermogravimetric analysis showed that the POC nanofibers had a better thermal stability than POC microspheres. The conductivity of POC nanofibers could reach 5.5×10-3S/cm, while the microspheres were almost insulators.
Nanocrystalline Diamond Film Deposited by Double Bias-Voltage Assited HF-PECVD System
Authors: Zhang Yong , Zhang En Lei , Lin Zhao Long
Published: August 2015

A new process has been developed to obtain high density nanocrystalline diamond (NCD) film via a double bias voltage hot filament-assisted plasma enhanced chemical vapor deposition (HF-PECVD). The microstructure and characterization of the film were analysed by SEM, Raman and AFM. The results show that the NCD film has higher nucleation density and smooth surface, the nanocrysatalline size was in diameter of about 40 nm. Three Raman band near 1150m-1, 1330 cm-1 and 1590m-1 lie in the specrum. The growth mechanism of naocrystalline diamond film was analysized at last.
Micro-Drilling of Pre-Sintered Alumina Ceramic
Authors: Wang Mei Li , Li Jian Zhong , Yu Zu Yuan , Li Xue
Published: August 2015

Ceramic materials are widely used in industries because of their excellent properties such as high hardness, strength, resistance to heat and corrosion. The high strength of sintered ceramics posts the difficulty to be processed into the desired shapes and dimensions. Direct processing of ceramic green body is easy to cause edge damage due to the lower strength, leading to low surface accuracy. When the green body of ceramics is pre-sintered, the mechanical strength of green body is enhanced and the machining accuracy is improved. In this paper, micro holes are drilled in ceramics sheets pre-sintered at different temperatures. The influence of processing parameters is analyzed. It was found that the tool has the longest life when the pre-sintering temperature of ceramic green body was 800°C. The quality of the inlet and outlet of micro holes was improved significantly when the coolant was used in machining.
Micromechanical Properties of Glass-Filled Polyamide 6
Authors: Manas David , Ovsik Martin , Manas Miroslav , Stanek Michal , Stoklasek Pavel , Bednarik Martin , Mizera Ales
Published: August 2015

The process of radiation crosslinking helps to improve some mechanical properties of polymer materials. Micromechanical changes in the surface layer of glass-filled PA-6 modified by beta radiation were measured by instrumented test of microhardness. The specimens were prepared by injection technology and subjected to radiation doses of 0, 66, 99, 132 kGy. Measurements of microhardness showed considerable changes of behavior of surface layer in middle as well as high radiation doses with higher values of indentation hardness and stiffness.
Fabrication of Through-Hole TiO2 Nanotube Arrays by Bilayer Ti Foils Anodization
Authors: Ding Zheng Nan , Kong Zhi Jian , Liu Hua Yan , Chen Yin Fei , Zhang Ze Kai
Published: August 2015

Through-hole TiO2 nanotube arrays were successfully prepared by using mechanical coupling Ti/Ti foils as anode. By continuously anodization, one Ti foil was thoroughly fabricated into TiO2 nanotube arrays, and the bottom barrier of TiO2 nanotube arrays was extended to the other Ti foil layer. The physical gap between two Ti foils allowed the TiO2 nanotube arrays to be easily separated from the barrier layer. Thus the through-hole TiO2 nanotube arrays were obtained. The method is simple but effective to thoroughly remove the bottom barrier layer and obtain through-hole TiO2 nanotube arrays without any complicated processes.
Facile Synthesis of Co3O4/Nitrogen-Doped Graphene Composite and their Electrochemical Performances
Authors: Bao Wen Xiao , Zhou Qian Long , Zhang Tian Yu , Li Wei Long , Ren Zhao Yu
Published: August 2015

Co3O4/Nitrogen-doped graphene (Co3O4/NG) composites were synthesized by a simple hydrothermal method. The Co3O4/NG composites show a better electrochemical performance than the Co3O4/graphene (Co3O4/G) composite. The specific capacitance of Co3O4/NG electrode is 428 F/g (290 F/g for Co3O4/G electrode) at a current density of 1 A/g. As the current density was increased from 1 to 8 A/g, the capacitance of Co3O4/NG still retained 57%, significantly larger than that of Co3O4/G (40%). Moreover, over 94% of the original capacitance was maintained after 500 cycles (72% for Co3O4/G electrode), indicating a good cycle stability of Co3O4/NG electrode materials.
Biodegradable Oph-POSS/Poly(Lactic Acid) Nanocomposites: Morphology, Thermal Stability and Degradation Property
Authors: Sun Jie , Zhao Qiang Qiang , Cao Zheng Yan , Lv Hai Ning , Wang Cheng Qun , Cai Zai Sheng
Published: August 2015

The purpose of this work was to produce nanocomposites of polylactic acid with oph-POSS (octaphenyl-Polyhedral Oligomeric Silsesquioxanes)-based biodegradable polyester and study morphology, thermal stability and degradation property. Oph-POSS was synthesized via limited-hydrolytic condensation of phenyl trimethoxysilane catalyzed by tetramethylammonium hydroxide. By adding different mass fractions of oph-POSS into the PLA matrix, oph-POSS/PLA nanocomposites were successfully prepared by the solution casting method using chloroform as solvent. SEM(scanning electron microscopy) observations indicated that oph-POSS were homogeneously dispersed in the PLA matrix. The biodegradation rate of oph-POSS/PLA composites was higher than that of neat PLA, moreover, the degradations of neat PLA and oph-POSS/PLA composites underwent the surface erosion mechanism. It was found that the existence of oph-POSS enhanced thermal stability slightly of nanocomposites relative to neat PLA; however, the thermal degradation mechanism of PLA remained unchanged.
Study on Influence of Ca2+ Ions Doping at a Site on Magnetic Properties and Magnetocaloric Effect of Nominal Compositions La1.4Sr1.6-xCaxMn2O7
Authors: Zong Yun , Kang Di
Published: August 2015

Polycrystalline layered perovskite manganese oxides La1.4Sr1.6-xCaxMn2O7 (x=0,0.2,0.4,0.8,1.0,1.4,1.6) samples is prepared using solid state reaction.The XRD analysis shows that La1.4Sr1.6-xCaxMn2O7 (0 ≤ x ≤ 0.8) samples are Sr3Ti2O7-type tetragonal structure with space group I4/mmm and forms a layered perovskite structure; for the 1.0≤ x ≤1.6 series of samples the main phase is ABO3 type orthorhombic structure with space group Pbnm.For small amount of Ca2+ ion-doped sample (x= 0.2,0.4), induce serious Jahn-Teller(J-T) distortion of MnO6 octahedral.For a large number of doping (1.0≤ x ≤1.6) samples, ferromagnetic - paramagnetic transition occurs near the Curie temperature (Tc) from low to high temperatures.With increasing doping amount, the magnetization reached maximum at x=1.4 samples.Maximum magnetic entropy change of the three samples(x=1.0,1.4,1.6) reaches 0.84, 1.20 and 2.28 J kg-1 K-1 at 320,268 and 215K near the Curie temperature, respectively. The large magnetic entropy change effect under low magnetic field of the sample makes it an optimal candidate of room temperature magnetic refrigeration materials.
Anomalous Hall Effect of the Co Thin Film Deposited by High-Pressure Magnetron Sputtering
Authors: Zou C.Y. , Wang Lai Sen , Liu Xiang , Zhang Q.F. , Wang Jun Bao , Huang Zhi Ling , Wang Xiong Zhi , Luo Qing , Peng Dong Liang
Published: August 2015

In this paper, we studied the dependence of temperature and weak localization (WL) effect on the anomalous Hall effect (AHE) in strong disordered and poorly crystallized metal Co thin film deposited by high-pressure magnetron sputtering. The temperature coefficients of resistivity is positive at high temperatures and becomes negative at low temperatures, which is the typical characteristic of weak localization effect in dirty metal regime due to the strong disorder. The saturation anomalous Hall resistivity (ρAxy) have no scaling relation between ρxy and ρxx in weak localization region with temperature below 50 K. In metal region, temperature ranged from 50 K to 300 K, the relation between ρAxy and ρxxis ρAxy=A+bρ2xx, which indicates that the AHE in this Co thin film is scattering-independence at high temperature. The results also shows that the WL effect have a significant impact on the AHE of the Co thin film at low temperature.
Structure, Magnetoresistance and Electrical Properties of La0.8SrxCa0.2-xMnO3 Compounds
Authors: Jiang Shao Qun , Wang Gang , Zhang Qi , Hou Jun Nan , Wang Ze Hua
Published: August 2015

The La0.8SrxCa0.2-xMnO3 (x=0, 0.05 and 0.15) compounds were synthesized by combining sol-gel method and high temperature sintering. The effects of Sr doping content on the microstructure, metal-insulator transition and magnetoresistance (MR) of the La0.8SrxCa0.2-xMnO3 were investigated. The results show that the La0.8SrxCa0.2-xMnO3 exhibit single perovskite phase and the change of Sr doping content can result in phase structure transition. The La0.8Sr0.15Ca0.05MnO3 is rhombohedra structure and the La0.8SrxCa0.2-xMnO3 shows distorted cubic structure when x is no more than 0.05. Increasing Sr doping content causes the degeneration of microstructure homogeneity and density and the decrease of average grain size of the La0.8SrxCa0.2-xMnO3, which can be attributed to the weakening of atomic diffusion during the sintering process. The metal-insulator transition temperature (TMI) of the compounds increases with the decrease of Sr doping content due to the improvement of microstructure. The La0.8Sr0.15Ca0.05MnO3 has the highest MR peak value, which is about 95%. The La0.8Ca0.2MnO3 has the highest room temperature MR, which is about 28%. Moreover, the magnetoresistance of the La0.8Ca0.2MnO3 is very stable between 125~300K.
Liquidus and Wettablity of Lead-Free Solder Alloys
Authors: Wang Hong Mei
Published: August 2015

This paper provides a new lead-free alloys with Sn, Ni, P and Mg. The liquidus of Sn-Ni alloys, Sn-P alloys, and Sn-Mg alloys was tested. And each of element affection was analyzed. The wettablity of Sn-Ni alloys ,Sn-P alloys, and Sn-Mg alloys was tested. And each of element affection was analyzed. In addition, the comparison of the liquidus and wettablity of different alloys was gave.
Phase-Field Simulation for Effect of Annealing Temperature on Oxygen Clusters’ Evolution in Silicon Wafer
Authors: Xiang Ji , Guan Xiao Jun , Wang Jin
Published: August 2015

In order to investigate the effect of annealing temperature on oxygen clusters’ evolution in silicon wafer during low temperature annealing, a phase-field model and it’s algorithm were established, and the changes of the oxygen clusters’ structure, amount (concentration) and sizes were simulated at different annealing temperature. The results show that when the temperature varies from 923 to 1023K, the oxygen clusters with reasonable amount and average size can be gained; when the temperature is too higher or lower, the suitable oxygen clusters cannot be found; it is verified that the established model and its algorithm have credible thermodynamics and experimental basis.
Fabrication and Characterization of Anti-Microbial and Anti-Ultraviolet Nonwoven by Electrospinning
Authors: Sun Shun Xiang , Zhao Hao Yu , Li Shu Bai
Published: August 2015

A kind of nonwoven containing ferulic acid is prepared by electrospinning method. It was observed that the diameter of the fiber was about 200 nm by SEM. The antibacterial activities againstEscherichiacoliandS. aureuswere also investigated. The result showed the nonwoven prepared was effective against Escherichia coli, andS. aureus. Furthermore, Fabric UV transmittance test and air permeability were taken. It was found that the nonwoven achieved good UV protection and air permeability.
Characterization of Carbon Composites Properties for Application in Sport Industry
Authors: Fojtl Ladislav , Rusnáková Soňa , Žaludek Milan , Čapka Alexander , Rusnák Vladimír
Published: August 2015

In the present work, mechanical properties of prepreg carbon composites are studied. Five types of composite samples with different number of layers and prepreg material corresponding to material composition used for carbon rims are manufactured by compression molding. Prepared composites are tested and compared with respect to flexural strength and modulus. Furthermore, impact performance using Charpy impact test is also evaluated.
Experimental Investigation of Possibilities Vacuum Infusion Technology to Produce Composite Ribs
Authors: Rusnáková Soňa , Fojtl Ladislav , Žaludek Milan , Čapka Alexander , Rusnák Vladimír
Published: August 2015

In the present work, mechanical properties and bending stiffness of composite structures with ribs are studied. The aim of this work was making ribbed composite structures in one step, where the ribs are inserted between glass reinforcement of composite system. In practice, the ribs on the composite structure (final products) are glued, but where there is a lower strength (according to the type of surface, the surface treatment, suitable bonding technology, the type of glue) and the adhesives are relatively expensive. The production of samples was used technology of vacuum infusion under flexible foil.
Research on Pipe Clamps Made of Resin Matrix Composites
Authors: Li Song Mei , Wang Zhuo , Zhang Bo , Zhang Jian Yong
Published: August 2015

When offshore oil field has been completed and put into production, the new subsea pipelines and cable will need to be established. Cable protection pipe clamp is used to fix cable protection pipe on the jacket. In order to avoid the problem of traditional steel structure clamps which was difficult to joint, align and fasten when it installed cable protection pipe underwater, reduce the risk and workload underwater, This paper will study a new type of portable connecting riser clamp made of resin matrix composites which can solve the installation problem which is difficult to install cable protection pipes underwater. The main structure of pipe clamps made of resin matrix composites used three divided-plates type of structure. The load characteristic of clamps was determined by Morison equation which is a classical theory and clamps underwater mechanics analysis model was established. The results show that the strength of the base of clamps meet the requirements after strength analysis with finite element analysis method, stability and strength experiments, which means the clamps made of resin matrix composite is feasible.
Synthesis and Characteristic of Borazine-Silicon-Containing Arylacetylene Resin
Authors: Zhou Chao , Guo Kang Kang , Qi Hui Min , Zhu Ya Ping , Wang Fan
Published: August 2015

Borazine-silicon-containing arylacetylene (PBZSA) resin was a novel organic inorganic hybrid polymer and prepared through condensation reaction among B,B’,B’’-trichloroborazine, dichlorosilane and arylacetylene Grignard reagent. The chemical structure of PBZSA resin was characterized by FT-IR and 1H NMR. The thermal stability and dielectric properties of cured PBZSA were investigated by TGA and broadband dielectric spectrometer. The results indicated that cured PBZSA showed high thermal stability with char yield up to 87.1% at 1000°C and at decompose temperature (Td5) 580°C, and low dielectric constant (2.8-2.9) and dielectric loss (<0.005).
Effect of the Iron Ion Doping in LaCoO3 Perovskite, Both in Powders and in Sintered Samples Obtained from Combustion Reaction and Solid State Route
Authors: Ribeiro Daniel Véras , Paula Gustavo R. , Morelli Márcio Raymundo
Published: August 2015

The aim of this work is to show the effect of the iron ion doping in LaCoO3 perovskite, both in powders and in sintered samples obtained from combustion reaction and solid state route. The phase formation and particle morphology and particle size distribution of the powders were analysed by XRD, SEM and sedimentation techniques, respectively. Relative density, microstructure (secondary phases and grain size) and pore size distribution of LaCo1-xFexO3 sintered ceramics were investigated by SEM/EDS and Hg porosimetry analysis. Although LaCo1-xFexO3 powders obtained from the combustion reaction exhibited smaller grain sizes when sintered at high temperatures, they showed a higher volume fraction of secondary phases. The presence of these crystalline phases in addition to the desired perovskite affected the microstructure acting as grain growth inhibitors by grain boundary pinning. It is believed that by observing three grain junction pores that the LaFeO3 phase has a smaller dihedral angle than LaCoO3. This fact would explain why LaFeO3 presented a smaller driving force for sintering with a higher tendency of pore and inclusion coarsening at higher temperatures (1400°C).
Impact Damage Analysis and Experimental Test of Carbon/Epoxy Composite Laminate
Authors: Choi Hyoh Yun , Lim Yeon Jun , Cho Hyun Jun , Park Hyun Bum
Published: August 2015

In this work, study on impact damage FEM model of composite structure was performed. From the finite element method analysis results of composite laminate, it was confirmed that the results of analysis was reasonable. The velocity of impactor to initiate damage was estimated, and in order to investigate the damage at the predicted velocity, impact analysis using finite element method was performed. According to the impact analysis results of composite laminate, it was confirmed that the damage was generated at the estimated impact velocity. Finally, the comparison of the numerical results with those measured by the experiment showed good agreement.
Improving the Surface Wettability of Parylene C Film by Hyperthermal Hydrogen Induced Cross-Linking Technology
Authors: Shao Hong , Tang Chang Yu , Shuai Mao Bing , Xu Ke Qing , Zhou Yuan Lin , Hu Xin , Qi Jing Jing
Published: August 2015

In this paper, we present a new approachcalled hyperthermal hydrogen induced cross-linking (HHIC) technology,which can successfully enhance the surface wettability of Parylene C (PC) film via cross-linking hydrophilic polyacrylic acid（PAA）on its surface. Water Contact Angle Meter and Fourier Transform Infrared Spectroscopy (FTIR) were used to characterize wetting property, surface chemical structureof PC film before or after HHIC treatment,respectively. The results show that PAA with polar functional groups can be successfully grafted onto the PC film. As a result, the water contact angle of the modified PC membrane surface decreased from 84° to 23°,PC membrane surface wettability is improved effectively.
Preparation of an Active Packaging Material and its Application on Strawberry Preservation
Authors: Fu Ya Bo , Xu Wen Cai , Fu Lu , Li Dong Li , Wang Jian Qing
Published: August 2015

To reduce the loss of fresh fruits during transportation and storage, an active packaging (AP) material which could control release fungicide was prepared by melting, blowing film and composite method firstly. Then, its preservation effects on strawberry at different storage temperatures were investigated systematically. Several properties of preserved strawberries were measured periodically, including gas concentration of the package atmosphere and the physiological parameters contains decay rate, total solid content, as well as the sensory and taste evaluation were measured. The experimental results show that this AP material is helpful to fruit preservation, especially at lower temperature. It can prohibit the strawberry respiration, retard fungus growth and thus significantly extend the shelf-life of fresh strawberry.
Slashing and Weaving Properties of Twisted Carbon Fiber Yarns
Authors: Li Qiang , Guo La Mei , Huang Wan Zhen , Ling Chao
Published: August 2015

Carbon fibers are usually used in the form of filaments since they are low in expandability and quickly wear and tear by bending. However now with the development of spinning technology, twisted carbon fiber yarns have been produced. In order to investigate the slashing and weaving properties of twisted carbon fiber yarns slashed by polyacrylate sizing agent at the room temperature, size picks up, tensile strength and abrasion resistance were introduced. Furthermore, a small piece of plain fabric was finished on the sample weaving machine. The results prove that slashing with polyacrylate sizing agent improves the slashing and weaving properties of twisted carbon fiber yarns significantly. Further, when the solid containing rate of polyacrylate slurry was around 5%, the size picks up can be up to 5.5%, the tensile strength increases by 19.8% and the wear resistance increases by 66.7%. Moreover, by using high-temperature water bath downsizing method, the sizing agent subsided frequently.
Mechanical Properties of the PcBN-Alcomposites are Improved by Pressure Infiltration
Authors: Duan Wen Rui , Kou Zi Li , Wei Li Min , Yang Xing Hui , Li Chun Xia , Chen Hong Yang
Published: August 2015

PcBN–Al composites（PAC）have been synthesized by pressure infiltration(PI) and a general mixing method(GM)[1-3] with a wide grain sizes range of 4-25 um and a wide temperature range of 1200-1600°C at 5.0 GPa,respectively.Hardness ranged between 30and 40 GPa, while the flank wear (Vb) reached 0.12mm when it finished 4000m in cutting test ofPAC synthesized by PI method. Hardness ranged between 25 and 35GPa, while the flank wear (Vb) reached 0.14 mm when it finished 4000mof PAC synthesized by GM method. The homogeneity of PcBN–Al synthesized by PI have been improved compared with GM. PI is a superior method to synthesize PAC in the field of mechanical properties.
Improvement in Corrosion and Adhesion Resistance of a Al2O3-CeO2 Nanocomposite Coating on the Aluminum Alloy AA6061 via Surface Pretreatment
Authors: Han Yu Mei , Farzaneh Masoud
Published: August 2015

In the present study, a surface pretreatment method consisting of KOH etching followed by oxide thickening in boiling water was used to improve the corrosion and adhesion resistance of the coating. The coating morphology on non-pretreated and pretreated Al substrates was characterized by means of scanning electron microscopy (SEM), atomic force microscopy (AFM) and water contact angle measurement. FT-IR spectra was obtained by Fourier transform infrared spectrometer. The corrosion resistance of the coating in 3.5 wt.% NaCl solution was evaluated with potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS) techniques. The adhesion resistance of the coating was tested using ISO-2409 standard. Results show that KOH etching followed by oxide thickening in boiling water can effectively improves the corrosion resistance and durability of the coating. Besides, this surface pretreatment method can also improve significantly the adhesion resistance of the coating.
Effect of Sintering Temperature on Phase Formation and Dielectric Properties of PLZT-BT Ceramics
Authors: Chumprasert Ladapak , Funsueb Narit , Limpichaipanit Apichart , Ngamjarurojana Athipong
Published: August 2015

In this research, Barium titanate (BT) additive in lanthanum modified lead zirconate titanate (PLZT) was used to stabilize the PLZT ceramics. Oxide powders were synthesized by mixed oxide synthetic route via a rapid vibro-milling technique. It was prepared with the chemical formula of 0.95 Pb0.91La0.09 (Zr0.65Ti0.35)0.9775O3 -0.05 BaTiO3 to investigate the dielectric properties of PLZT ceramics. The modified PLZT ceramics were fabricated at variation of sintering temperatures of 1200-1275°C for 4 hours. By employing X-ray diffraction (XRD), it was found a pure perovskite with rhombohedral structure. The relaxor behavior was observed from the dielectric measurements. The suitable sintering temperature of 0.95 PLZT - 0.05 BT was 1275°C (εr=10463, tanδ=0.0125 and Tm=70°C).
Synthesis and Characterization of CeO2-Al2O3 Nanocomposite Coating on the AA6061 Alloy
Authors: Han Yu Mei , Farzaneh Masoud
Published: August 2015

In the present study, a thick, uniform and crack-free sol-gel coating embedded with Al2O3-CeO2 nanoparticles was successfully synthesized and deposited on aluminum alloy AA6061 by spin coating method. The coating morphology was characterized by using a scanning electron microscopy coupled with electron diffraction x-ray spectrometer (SEM-EDX), an atomic force microscopy (AFM) and water contact angle measurements. FT-IR spectra were obtained using a Fourier transformation infrared spectrometer. The corrosion resistance of this coating in 3.5 wt.% NaCl solution was evaluated with electrochemical methods including potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS). The stability of the corrosion resistance of this coating was evaluated by immersion in 3.5 wt.% NaCl solution and by exposure to the UV radiation condition. In addition, the adhesion resistance of the coating was also assessed. SEM and AFM results showed that Al2O3-CeO2 nanoparticles dispersed uniformly in the room temperature vulcanized (RTV) silicon rubber matrix and formed a thick and crack-free coating. Both polarization and impedance results reveal that CeO2-Al2O3 nanoparticles embedded silicon rubber coating can improve the corrosion resistance of the AA6061 alloy by more than three orders of magnitude. Meanwhile, the corrosion resistance of this coating was found to be stable under immersion in 3.5 wt.% NaCl solution and UV exposure conditions. However, excessive content of CeO2 nanoparticles in the coating made the coating morphology porous and decreased the thickness of the coating, which resulted in the decrease in the corrosion resistance of the coating.
Plant Compound Curcumin Mediates Calcineurin Activity to Upregulate ABCA1 Expression in a Model of Alzheimer’s Disease
Authors: Xu Ke , Zhang Xiong , Yu Li
Published: August 2015

Cholesterol metabolism plays an important role in pathogenesis of Alzheimer’s disease (AD). Curcumin has been reported to decrease cholesterol in serum through increasing the cholesterol efflux transporter ATP-binding cassette transporter A1 (ABCA1) expression, but the underlying mechanisms are not fully understand yet. To investigate the effects of curcumin on the activity of calcineurin and the expression of ABCA1 in vitro, N2a/APP695swe cells were treated with curcumin at 5 umol/L for 24 h, or with the calcineurin activity inhabitor CyclosporinA (CsA) at 0.5 umol/L for 48 h. Our findings showed that curcumin could increase the expression of the ABCA1 at mRNA and protein levels, furthermore, it could inhibit the calcineurin activity, CsA also could increase the expression of the ABCA1 at mRNA and protein levels. These findings suggest that curcumin may upregulate the expression of ABCA1 via inhibiting the calcineurin activity in N2a/APP695swe cells.
The Progress in Cloning, Expression and Purification of Cholinesterase in Pichia pastoris: One Kind of Biomaterial for the Detection of Residual Insecticide Contamination
Authors: Tian Jing Jing , Xie Yuan Hong , Chen Xiang Ning , Yue Xi , Guo Zhen Long , Xu Wen Tao
Published: August 2015

Cholinesterase serves as a key enzyme of the cholinergic system, which could be one kind of promising biomaterial to assay OP and CB residues. However, cholinesterase purified from tissues or blood is both time and cost intensive. In this essay, different methods via biotechnology to get this biomaterial in Pichia pastoris is summarized, including cholinesterase gene cloning and expression vector construction, construction of genetic modified yeast, screening high yield transformant, purification from supernatant and activity analysis.
Production, Characterization and Bioactivity of 46S6 Bioactive Glass from Rice Hull Ash Silica
Authors: Yücel Sevil , Aydın Sinirlioğlu Zeynep , Karakuzu Burcu , Temel Tülay Merve , Elalmış Yeliz , Özarslan Ali Can
Published: August 2015

In the present study, 46S6 bioactive glasses with composition 46 SiO2% –24% Na2O – 24% CaO – 6% P2O5in weight percent were synthesized through melt-derived process using alkali extracted silica from rice hull ash and commercial silica. Bioactive glasses were incubated in SBF (simulated body fluid), before and after immersing in SBF, characterized by SEM to investigate degradation and apatite formation. Also bioactivity tests such as cell culture, cell viability and cytotoxicity, differentiation, mineralization and alkaline phosphatase assay have been performed. Results showed that 46S6 bioactive glasses from rice hull ash silica had better metabolic activity and viability than that obtained from commercial silica.
Sliding Wear Behavior of AM60 Alloys with Alloyed Yttrium
Authors: Zhang Qian Qian
Published: August 2015

In this study, the wear behavior of AM60 alloys adding different amounts of yttrium (0, 0.5, 1, 1.5, and 2 wt%) during dry sliding has been investigated. The microstructure observation and EDS analysis demonstrated that adding yttrium in AM60 alloy formed a new phase Al2Y and minimized the precipitation of Mg17Al12 phase. The wear rate and friction coefficient of AM60 alloys adding yttrium were lower than that AM60 alloy under the same condition. The worn surface was covered with long continuous grooves parallel to the sliding direction. The wear resistance of AM60 alloy was improved when yttrium was added due to the formation of uniformly is tribute finer and harder Al2Y precipitates. The harder Al2Y precipitates increased the hardness and wear resistance of the AM60 alloy and reached the maximum at 1 wt% Y.
Reconstruction of the Municipal Bath House
Authors: Čajka Radim , Burkovič Kamil
Published: August 2015

The paper describes static failures, reconstruction and redevelopment of reinforced concrete load-carrying structures in the Municipal Bath House in Moravská Ostrava. The building was built at the beginning of the 1960s.The architectural, structural and typological features are typical of that time. Several rather serious failures have occurred during the operation in the reinforced concreted load-carrying skeleton and the bath tub structure. Reasons for the failures and general degradation of some parts of the reinforced concrete included undermining, weather, leakage of aggressive water and vapour from baths, saunas, laundry and other facilities. This paper describes the static underpinning, improvement of the degraded reinforced concrete structures and technical aspects of transformation of a former civil defence shelter into a wellness and swimming centre.
Termographical Measurement of the Surface Temperature and Emissivity of Glossy Materials Using the Method of Four Points
Authors: Čmiel Filip , Solař Jaroslav
Published: August 2015

The practical determination of the surface temperature and emissivity of glossy materials using the infrared thermography is carried nowadays in the way that the surface is covered with a material which has a known value of emissivity. The mentioned values are, however, possible to be determined even without the materials which havae a known value of emissivity: using the infrared radiation, which is reflected by the glossy surface and is detected by the termographical device afterwards. The contribution deals with the possibility of determination of surface temperature and emissivity of glossy materials by the mentioned method.
Thermally-Technical Comparing of Traditional Double Timber Window and Eurowindow
Authors: Balík Lukáš , Kudrnáčová Lucie
Published: August 2015

The windows are situated on the northwest part of facade of historically valuable residential building in Prague. The building was erected in 1935-37 in functionalism style according to project of architect Richard F. Podzemný. The building has got status of cultural heritage and its structure is formed by reinforced concrete load bearing frame with lining bricks. Traditional double timber windows in the building still exist, but are currently in poor technical condition. According to project of reconstruction the exchange of existing windows by new simple eurowindows with sealed unit was designed. In accordance with the requirements of conservationists the same dimension of glazing and frames of windows in exterior were to be conserved. Existing and planned windows were from thermally technical aspects calculated by two dimensional model software system Area 2011.
Numerical Investigation of Reinforcing a Masonry Column with Fiber Reinforced Strain Hardening Cementitious Composite
Authors: Jašek Marek , Brozovsky Jiri
Published: August 2015

Fiber reinforced strain hardening cementitious composite is very deformable fine-grained concrete with the matrix based on Portland cement reinforced with short fibers. This composite material represents a new generation of high performance concrete (HPC) and it is also known as flexible concrete. Its characteristic property is that after reaching the strength when the first crack appears "hardening" of the material occurs, i.e. increases the stress and at the same time increases the strain until the ultimate strength of the material is achieved. One of the possibilities is the use of composites in the reconstruction and rehabilitation of buildings. The paper deals with the numerical assessment of the possibility of using fiber reinforced strain hardening cementitious composite during the reinforcement of an axially loaded brick column.
The Corner Radius Influence on the Deformation Behavior of Brick Pillars Strengthened by CFRP Confinement
Authors: Kubat Jan , Karas Jiří
Published: August 2015

The article addresses the issues of the application of materials based on high-strength carbon fibers as external glued transverse confinement of concentrically compressed masonry pillars. Transverse confinement of compressed pillars contributes to their enhanced load-bearing capacity and ductility due to the introduction of horizontal forces and creation of multi-axial compressive loading of masonry.The article describes experimental research within the NAKI, DF12P01OVV037 research project. The research was carried out on a set of brick pillars with dimensions of 286 x 286 x 870 mm, reinforced by confinement in carbon fibers in an epoxy resin matrix. The corner edges of brick pillars were treated by rounding with radii of 20 mm, 35 mm, 50 mm and 85 mm. To conclude, the article compares differently treated pillars in terms of the ultimate load reached, the deformation behavior, stress states in the transverse reinforcement, the pillars’ failure mode and the crack pattern along the cross section. Based on the comparison, some findings are formulated.
Research of Fire-Retardant Properties of Timber Constructions, Protected Geocement-Based Coating, after their Operation
Authors: Kravchenko Anastasiia , Guzii Sergii , Tsapko Yurii , Petranek Vít
Published: August 2015

Was conducted survey of condition and fire-retardant properties of surface of timber constructions, protected by coating on geocement-based, after their operation under atmospheric conditions. For a comprehensive assessment of fire-retardant determined following characteristics: type of corrosive environment; duration of operation of structural elements coated; coating thickness and integrity; cracks; adhesion of the coating to the timber; determination of the fire-retardant properties of the coating. Assessment of the results obtained, despite the significant deterioration in the appearance of geocement-based coating retains its primary function, fire protection, having after one year of operation, – 1 group of combustibility.
Protecting the Brickworks against Technical Seismicity
Authors: Solař Jaroslav
Published: August 2015

In the Czech Republic, there are seismic territories with little natural seismicity only.On the other hand, the technical seismicity is frequently a pressing issue.Dynamic responses caused by the technical seismicity result in defects − in particular, in cracksin brickworks. This paper discusses possible technical and structural measures which eliminate effects of the technical seismicity and, in turn, reduce risk of damage to the brickworks..
Determination of Grain Boundary Diffusion Parameters Based on Specified Model of Grain Boundary Diffusion and Combined Analysis of Radiotracer and Mössbauer Spectroscopy Data
Authors: Popov Vladimir V. , Sergeev A.V.
Published: August 2015

The classical Fisher model of grain-boundary diffusion and the traditional method of determination of grain-boundary diffusion parameters by radiotracer technique combined with the serial-sectioning method are analyzed. The Fisher model specification based on the data of the emission Mössbauer spectroscopy is considered, and the additional information which can be extracted from the Mössbauer studies is discussed. The possibility of determination of grain-boundary diffusion parameters based on the combined analysis of the radiotracer technique and Mössbauer spectroscopy with the application of the specified Fisher model of grain-boundary diffusion is considered. This approach is demonstrated by an example of determination of grain-boundary diffusion of Co in W and Mo.
Study on Bioforming Technology of Bionic Micro-Nano Structures
Authors: Zhang De Yuan , Cai Jun , Jiang Xing Gang , Han Xin , Chen Bo
Published: August 2015

The connotative meaning and trend of bionic design and manufacturing was analyzed. A new bioforming technology was presented, which will offer a new way to solve the difficulties in manufacturing of bionic micro-nano structures, and the layout of bioforming technology was also plotted. Several different bioforming technologies targeting typical bionic products were introduced. Compared with traditional manufacturing methods, to machine complicated micro/nano shapes, structures, functional interfaces with bioforming technology has more advantages, which showed that bioforming technologies would have great potential applications in energy-saving, environmental protection, and micro/nano fields.
Development of Novel XY Micropositioning Stage
Authors: Chen Hua Wei , Jiang De Huai , Hagiwara Ichiro
Published: August 2015

Along with the rapid development of semiconductor, photonics and ultra-precision engineering, ultra-precision positioning stages are becoming more necessary than ever. In this study, one novel XY micropositioning stage is proposed, in which bi-axis circular notch flexure and cantilever hinge mechanism are optimal designed as bearing to provide smooth and guided motion. The theoretical stiffness of stage is provided and verified by FEM analysis. Finally, the micro-positioning stage is built and its resolution is experimentally validated to be less than 4nm.
Grey System Theory Modeling for Nonlinear, Dynamic Machine Tool Thermal Error
Authors: Yan Jia Yu , Yang Jian Guo
Published: August 2015

To accommodate the nonlinear and dynamic nature of thermal elastic process, Grey System Theory (GST) is adopted. By using this theory, GM (2, 1) and GM (1, 4) models are constructed. Real cutting experiment on a turning machine is conducted to establish and validate the model performance in terms of generalization ability. The comparison indicates that GM (2, 1) and GM (1, 4) perform better than other static and dynamic models such as Back Propagation Neural Network (BP) and Auto-regression Moving Average (ARMA). In addition, each of the two proposed model has their own advantages and they can be applied in practice.
Bending Fatigue Characteristics of WC-βt-Co Alloys
Authors: Sakagami Kusuhiko , Kouno Shinichi , Yamamoto Tsutomu
Published: August 2015

WC-βt-Co alloys have been widely applied to cutting tools because they are superior to WC-Co alloys in oxidation, plastic deformation and adhesion resistances. In this study, the effects of HIP treatment, WC grain size and content of βt phase on bending fatigue characteristics were investigated for fine and coarse-grained WC-6.7mass%βt-10.4mass%Co alloys （6.7βt(F) and 6.7βt(C) alloys） and fine-grained WC-20mass%βt-11.3mass%Co alloy (20βt(F) alloy) by comparing with the case of fine-grained WC-10mass%Co alloy（10Co(F) alloy） without βt phase.
The results obtained were as follows: 1) The bending fatigue life of HIP-ed 6.7βt(F) alloy was longer than that of normally sintered 6.7βt(F) alloy. The S-N curve of HIP-ed alloy showed a small gradient in a high stress range and a large gradient in a low stress range. 2) The fatigue life of HIP-ed 6.7βt(F) alloy remarkably decreased in the high stress range, but slightly decreased in the low stress range, compared with that of 10Co(F) alloy. 3) The fatigue life of HIP-ed 6.7βt(C) alloy was superior in all the stress range, compared with that of HIP-ed 6.7βt(F) alloy. 4) The fatigue life of HIP-ed 20βt(F) alloy was shorter than that of 6.7βt(F) alloy in all the stress range．The above-mentioned results were mainly discussed relating to the fatigue fracture origins such as pore, Co pool, agglomerate of βt grains, etc.
Basic Study on the Development of the General Purpose Vertical Milling Machine for Educational Skill Training
Authors: Sawa Takekazu , Okabe Masayuki , Siga Akio , Mutoh Masami , Kurihara Takayuki , Unno Kuniaki
Published: August 2015

In this study, covering for the skill training centers in Japan, we performed surveillance study about the functions required for the general purpose milling machines for educational skill training. As a result, it was found that the function of recognizing machining state is desired for milling machines besides higher stiffness, higher accuracy, and the ease of chip treatment. Based on this fact, the general purpose vertical milling machine was developed for educational skill training. First, a beginner's work analysis was conducted and the functions which control the mishandling were developed. The operation mistake has decreased by this function. In addition, the cutting power inspection system was built by using high sensitive micro-wattmeter. And, the possibility of judgment of tool wear was found by inspecting the change of the wave profile in the wattmeter.