bluuebunny/crossref_metadata_2025 huggingface dataset:
The Research on Management Mode of Regional Distribution Network
Authors: Liu Lin , Yuan Li Li , Ma Yu Ming
Published: October 2014

Big Run" system construction is a major change in network operation mode, a new mode of distribution network in the regulation of business was placed under a unified power dispatch control center. In order to protect the "big run" a new system of distribution network under the smooth development of the business, in all the work involved in the distribution network, the primary network management standards extends to the distribution network, enhanced distribution network run technical support, regulate distribution network regulation related to business management, improve the management level of the grid with standardized operation, guarantee safe and stable operation of the distribution network.
The Channel Characteristic and AMR Field Trial Results in China Distribution Grid
Authors: Gu Zhi Ru , Liu Da Wei , Liu Hong Li , Tan Zhou Wen
Published: October 2014

Power line communication (PLC) has received much attention recently because of the need of reliable and automatic metering, In this paper we present a comprehensive study over the use of PLC in China. We begin with some background including the distribution grid topology, the power line channel environments, and the deployment of PLC network. Then we show some field test results of PLC-based meter-reading in a high frequency band. In addition, a suggestion how to improve G3-PLC is presented which can adapt China grid better.
Analysis and Optimization of Elastic Expansion Sleeve Based on the Finite Element
Authors: Fu Hu Dai , Gao Jin Gang , Li Wei Wei
Published: October 2014

The contact finite element method is proposed to analyze the stress and deformation distribution of elastic expansion sleeve in the paper. The maximum stress position of each component under the most dangerous working condition is obtained. The effect of structure dimension on stress and deformation of elastic expansion sleeve is found out. The structure dimension meeting the practical requirements is gotten. The analysis results provide the reliable theory basis for the design. The optimization for the structure and processing technology of elastic expansion sleeve is realized, based on simulating the design structure.
Self-Tuning Predictive PID Controller Using a Time-Varying Proportional Gain
Authors: Jia Rong , Liu Bin , Fang Kai
Published: October 2014

This paper proposes a new design method of adaptive GPC-based PID controller. The proportional gain of a PID controller is time-varying, and the PID controller is designed based on strongly stable GPC that is extended by using coprime factorization. Hence, a GPC law can be approximated by the PID controller finely. Finally, the system parameters are updated in real-time to resist to disturbance, by using the RLS method. Simulation examples show the effectiveness of the proposed method.
The Control System of Virtual Simulation and Speed Optimization on Assembly Manipulator
Authors: Gao Yue Hua , Hao Lei , Li Ya Peng
Published: October 2014

Considering the characteristics and control requirements of assembly line, we develop a virtual simulation system which combines virtual reality and electrical control technology. The system can be used in system monitoring, debugging and staff training. The electrical control program is written by software of Rockwell based on virtual PLC, which realizes the application of velocity curve in linear type and Cosine-linear type on the object of virtual simulation through the RSTestStand software to build 3D virtual simulation model of the automatic assembly system of manipulator. The motion visual effect and monitor curve on the object of virtual simulation can indicate that the control system works well. It can also reduce mechanical arm joint motion and force effectively, through the start and stop, acceleration and deceleration of the manipulator movement and optimization of the speed using cosine timing scheme in uniform conversion.
Research on Control Augmentation System for a Flying Wing Aircraft
Authors: Peng Cheng , Wang Xin Min , Qiu Chuang
Published: October 2014

Requirements of the longitudinal control augmentation system are presented through studying the 25thChina Civil Aviation Regulations and C* flight quality evaluation criterion; The C* control augmentation scheme commonly used in modern large airliners is adopted to design the control augmentation system due to the stability and handling problems for the flying wing aircraft; The particle swarm optimization algorithm is proposed due to the parameter-scheduling difficulties in the designed control augmentation system. Numerical simulation shows that the designed C* control augmentation scheme is feasible.
Design and Realization of Wireless Lighting Control Based on ZigBee
Authors: Zheng Ying , Wang Mi Mi , Chen Hui Qin , Huang Li Wei , Zhang Li Zhen
Published: October 2014

The low utilization rate of the traditional lighting system lighting and the overall layout and wiring costs high affecting the overall appearance and so many problems. This design of an intelligent lighting control system based on ZigBee technology. Using ZigBee CC2530 of the TI Company, the system researches and designs a sending module and a receiving module of intelligent wireless lighting control system. The ZigBee terminal node sends control signal to the coordinator node. The coordinator node CC2530 output of PWM wave signal according to the control instruction signal. the output of the PWM wave signal controlled the LED brightness through PT4115 chip LED driver circuit. Through tests,the results show that it can meet the demand of daily light regulation.
A Study on Parameter Tuning of Fractional Order PIλ-PDμ Controller
Authors: Bian Hui Juan , Qi Zhi Dong , Shan Liang , Leng Bo Yang
Published: October 2014

Aiming at a kind of special object with fractional characteristics,a new kind of fractional order PIλ-PDμ controller is put forward in this paper,In this control system, the forward channel of system contains a fractional order PIλ controller,while the feedback loop adopts PDμ controller.The control structure in this fractional order system can achieve a good performance of the closed loop control.Moreover,the impacts on system dynamic performance and static performance are compared when the parameters in the controller are changed.The results show that when these parameters are in the reasonable range,the system can achieve better control performance.
The Preparation and Research of the Electroless Plating Rare Earth Alloys
Authors: Qin Xiu Lan , He Lin Jie , Wang Yan Li , Wang Ke , Gao Ming Ming , Zhang Yang , Yang Xin Ke , Chen Qian , Dong Wei Hua , Zhang Lu
Published: October 2014

The Ni-Fe-La-P rare earth alloys of glass fiber were prepared. Rare earth element lanthanum (La) was first introduced into glass fiber by electroless plating, in order to improve and adjust the chemical, physical properties and microstructure of alloy coatings. The application of rare earth element La in electroless plating was explored. The results showed that an appropriate amount of rare earth element La could improve the stability of the chemical plating solution and reduce the temperature of electroless plating by 6°C~ 20°C. The rare earth element La not only could make the morphology of alloy coatings compacted, smooth and uniform, but also could greatly improve the contents of Fe, Ni and could tremendously reduce the content of P in the alloy coatings of glass fiber. The conductivity and magnetic properties of the alloy coatings could be increased by rare earth element La. In the preparation of the Ni-Fe-La-P electroless alloys of glass fiber, the optimal content of La2O3was 1.2 g·L-1. Rare earth element La could promote the transition of alloy coatings from amorphous state to rystal state, improve the electromagnetic performances of alloy coatings and enhance the electromagnetic wave absorbing properties of alloy coatings.
Template-Directed Synthesis and Upconversion Luminescence of Y2O3 Hollow Spheres
Authors: Zhang Cui Miao , Wang Jian Yuan , Liu Ya Min , Jia Guang
Published: October 2014

Uniform Y2O3 hollow microspheres have been successfully prepared via a urea-based homogeneous precipitation technique with colloidal carbon spheres as template followed by a subsequent calcination process. The template can be effectively removed and the amorphous precursor has converted to crystalline Y2O3 during the annealing process. SEM images indicate that the hollow spheres inherit the spherical shape and good dispersion of the templates, and the shell of the hollow spheres is composed of a large amount of uniform nanoparticles. The lanthanide activator ion Ln3+-doped Y2O3 hollow microspheres exhibit bright upconversion luminescence with different colors under 980 nm light excitation, which may find potential applications in the fields such as light phosphor powders, advanced flat panel displays, or drug delivery.
Glucose Molecularly Imprinted Electrochemical Sensor Based on Chitosan and Nickel Oxide Electrode
Authors: Li Huai Xiang , Yao Wei , Wu Qiong , Xia Wen Sha
Published: October 2014

In this work, A molecularly imprinted polymers (MIPs) electrochemical sensor based on chitosan (CS) and nickel electrode was constructed, finally used in glucose measurement. The MIPs sensor was prepared through electrodepositing glucose–CS composited film on the electrochemical treated nickel then removing glucose from the film via water elution. The morphology and electrochemical properties of the sensor were characterized via scanning electron microscope (SEM) , cyclic voltammetry (CV), respectively. Amperometric responses of the CS (MIP)-NiO electrode toward glucose was well-proportional to the concentration of the range from 10 μM to 200 μM. The developed sensor obtained the specific recognition to glucose against coexisting interferences such as oxalic acid, uric acid and ascorbic acid.
Structural Characterization of Natural Rubber Recent Research Advancements
Authors: Wu Long Mei , Liao Shuang Quan , Qu Peng , Zhou Rong Jie , Wang Bo Xiang
Published: October 2014

The micro-structure of the surface of Hevea brasiliensis latex particles has been found by the means of atomic force microscopy (AFM), confocal laser scanning microscopy (CLSM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), cryogenic transmission electron microscopy (cryo-TEM), and electrokinetics over a broad range of KNO3electrolyte concentrations (4-300 mM) and pH values (1-8). Based on the atomic force microscopy analysis of the fresh natural rubber latex, it could be estimated that the protein-lipid layer is covered with the rubber particles. The molecules in the particle were labeled with fluorescent Rhodamine (RB), and were monitored by CLSM. SEM and TEM were used to observe the surface of fresh natural rubber particles and were dyed by osmium tetroxide. Fourier Transform Infrared Spectroscopy (FTIR) has been used to characterize the nitrogenous groups in natural rubber and deproteinized natural rubber (DPNR). The FTIR and1H-NMR analysis of phosphatase-treated DPNR confirmed that the presence of mono- and diphosphate terminations without phospholipids was also unlikely owing to the presence of a methylene proton signal of an isoprene unit linked to mono- and diphosphate groups. The , [η] and Higgins’ k’ of DPNR decreased after being treated with lipase.
Research on Performance of Polyimide In Situ Modification Anionic Polymerization Nylon 6
Authors: Zhao Hong Kai , Wang Hong Li
Published: October 2014

Through the polymerization and grafting reaction of bisphenol A dianhydride and bisphenol A diamine, the polyimide activator (PI activator) of acyl caprolactam end capping is obtained and then the anionic in-situ polymerization modified nylon 6 resin is obtained. Viscosity analysis shows that PI consumption is higher than 0.1 (of monomer mass), the reaction temperature is higher than 160°C, the viscosity rises rapidly in a short time and the rapid polymerization molding can be realized; when PI consumption is higher than 0.15 (of monomer mass), the water absorption of matrix resin will be lower than 1.4%; compared with the nylon resin, its water absorption is significantly lowered and its mechanical property is improved greatly; microscopic analysis shows that PI molecules fail to enter the crystalline phase of the nylon 6 and form lamellar crystals in the nylon matrix, which plays a role of enhancement and obstruction; differential thermal analysis shows that PI reduces the melting enthalpy and melting point temperature of nylon 6 resin, which indicates that PI reduces the crystallization capacity of nylon 6.
Inhibition of Potassium Citrate on Aggregation of Nano Calcium Oxalate Crystal in Four Different Systems
Authors: Wen Xiao Ling , Tan Cai Yan , Xue Jun Fa , Ouyang Jian Ming
Published: October 2014

The effects of potassium citrate (K3cit) on sedimentation and aggregation of 50 nm calcium oxalate dihydrate (COD) crystals was studied in order to explore the mechanism of formation and inhibition of kidney stone. In four different systems, including pure water, urine of healthy person and CaOx stone former before and after taking medicine K3cit, the influences of K3cit on average size (), Zeta potential and optical density of nanoCOD suspensions were studied by nanoparticle size Zeta potential analyzer and ultraviolet spectrophotometer. It was showed that K3cit could specifically adsorb on nanoCOD crystals, and also competed with the inhibitor molecules in urine. Due to the decrease of inhibitors in urine of patients, K3cit can be better to fulfill its inhibitory effect, leading to the largest reduced values of the diameter of COD crystal and the optical density of urine suspension. In conclusion, the inhibitory effect of K3cit on aggregation and sedimentation of calcium oxalate crystals is better in urine of patients, whereas the inhibitory effect has been reduced in urine of control group and patients after taking k3cit.
Energetic Studies on the B Effect on the Oxidation of γ-TiAl Alloys
Authors: Zhang Guo Ying , Liu Gui Li , Bao Jun Shan , Liu Chun Ming , Zhang Hui
Published: October 2014

The energetic study of B effects on the oxidation of γ-TiAl alloys are performed by using the first-principles method based on Density Functional Theory (DFT) in this paper. The surface and interface segregatation of B as well as of the surface adsorption of O are discussed. B is found to preferentially segregat to TiAl subsurface with respect to γ-TiAl bulk. The B segregation at surface decreases oxygen coverage in the initial oxidation process of γ –TiAl alloys, thereby it is beneficial to the decrease of the growth of γ–TiAl alloys oxide film. In the initial oxidation process, oxygen prefers to stay in the vicinity of surface Ti atoms, and B addition is beneficial for the decrease of the growth of A12O3and TiO2. After the formation of Al2O3oxide film, B is energetically favoured stayed at interstitial site of α-Al2O3(0001)/γ-TiAl (111) interface, and enhances the adhesion of this interface.
The Common Approaches to Study Compaction Process of Pharmaceutical Powders
Authors: Li Xiao Hai , Xu De Sheng
Published: October 2014

A good understanding of the compaction mechanisms of pharmaceutical powders allows accurate prediction of tablet quality and facilitates design of tablet formulations. In this area of research, a common practice is to examine the response of particles towards the pressure applied during compaction. To ensure accurate and reproducible experimental results, it is prudent to have an in depth understanding of the fundamental background and potential applicabilities of the compaction process. This article reviews methods that are widely employed to study the compaction process, such as mathematical models, compaction energetics, statistical analysis methods and mechanical element simulations. In view of the complex nature of the compaction process and current research gaps in understanding the compaction characteristics, particularly of pharmaceutical powder blends, some suggestions will be proposed as well.
The Effect of Natural Light and Ultraviolet Lamp Radiation on Bamboo Surface Discoloration
Authors: Nan Bo , Yin Li Ping , Wang Shu Qiang , Huang Cheng Jian , Li Yan Jun
Published: October 2014

This article explored the effect of natural light and ultraviolet lamp radiation on the discoloration of the green part of the 4-year bamboo by using the color analyzer and Fourier transform infrared spectrometer. The results showed that both light treatment could make the discoloration of the bamboos green part obviously, and the lightness increased, the color hue (a*) changed a little, however, the color hue (b*) had a great change, and the aberration (△E*) increased with the increasing duration. FTIR results showed that the chemical structure of the bamboos green part had a change, and the components of the lignin decreased because of the degradation, but the hydroxyl increased.
Carbon Fiber Reinforced SiC Matrix Composites Fabricated by Preceramic Impregnation and Pyrolysis Process Combining SiC Nano Powder Infiltration
Authors: Wang Jing Jing , Lin Wen Song , Duan Li Hui , Yan Xue Zeng
Published: October 2014

SiC nanopowder, polycarbosilane and divinylbenzene mixed slurries were prepared for viscosity measurement, which were used as matrix source of ceramic matrix composites. Results showed that apparent viscosity of the slurries increased with the increase of the content of SiC particles. The slurries with 50 nm SiC particles showed a low viscosity as compared with those slurries with 20 nm or 120 nm SiC particles at the same content of SiC. In particular, when the viscosity of slurry was higher than 30 mPa•s, the slurry could not be used in the test. Three-dimensional carbon fiber (3D-Cf) preforms were infiltrated with the aforementioned slurries. Addition of the nanoSiC powder as the inert filler in the slurries led to reduce the porosity and the infiltration–curing–pyrolysis cycles to manufacture 3D-Cf/SiC composites by the subsequent polymer impregnation and pyrolysis (PIP) process. Characterizations of the composites showed that the maximum flexural strength of specimen in the composites was 326 MPa and its fracture toughness was 10.5 MPa•m1/2.
Microstructure and Temperature Characterization of Compound Crumb Rubber Modified Asphalt
Authors: Wang Lan , Hu Jiang San , Chen Gang
Published: October 2014

Compound Crumb Rubber Modified Asphalt (CCRMA) is a mixture of waste rubber tire powder, SBS modifier and asphalt in order to modify the characteristics of asphalt. The application of using crumb rubber powder in making CCRMA is important in improvement of working characteristics of asphalt as well as in pollution control and environment protection. CCRMA, crumb rubber particles, SBS modifier and base asphalt have been examined by Scanning Electron Microscope (SEM) to observe the microcosmic appearance and the characteristic distribution of crumb rubber particles and SBS modifier in asphalt. The rotary viscometer test and dynamic shear test of CCRMA were carried out by rotational viscometer and Dynamic Shear Rheology (DSR). The influences of rubber powder content and reaction time to viscosity of CCRMA have been studied. In the stage of current study, complex modulus and phase angle of CCRMA are parameters reflecting viscoelasticity, the relation between them and temperature are researched.
Measurement of Complex Permittivity of Insulating Substrates with an Open-Ended Coaxial Resonator
Authors: Tian Kun Peng , Guo Gao Feng , Wang Jun Hu , Li En
Published: October 2014

A novel cavity perturbation technique utilizing open-ended coaxial resonator is presented in order to measure the complex permittivity of insulating substrates at microwave frequencies. This technique can afford quite high accurate measurement results without singularities, and simply. According to the operation frequency of the resonator, the geometric parameters of the resonator are designed. Based on the perturbation technique, a new formulaic method of data analysis has been proposed which can extract complex permittivity of samples, and with the resonant frequency and the quality factor shift, one can calculate the complex permittivity of the measured materials. Experiment has been conducted with the quartz and sapphire to verify the formulaic, and the test results fully verify the correctness of the proposed method.
Set-Up of a Test Bench for the Investigation of Single Parameter Effects in Abrasive Processes by Force Measurements
Authors: Bähre Dirk , Fang Shi Qi , Gliche Jacqueline , Trapp Kirsten
Published: October 2014

Abrasive processes are influenced by many different parameters. For a systematic investigation of these influencing parameters, a test bench for abrasive tools has been developed and set up on a 3-axis milling machine. The test bench is capable to control the machining parameters, such as the cutting speed and the feed speed, regulate the lubrication conditions, such as the temperature or the flow rate, and measure the cutting force during the process. Impacts of the single force components are investigated by means of the abrasive tools in contact with the rotating workpieces and the calculation of the tangential force coefficient. In this paper, the set-up of the test bench is explained and the systematic proceeding in investigating the impacts is exemplified by cooling lubricants because the surface of the workpiece, the wear of the tool, the temperature and the friction forces are often influenced by the type of cooling lubricant and its composition. The aim of the test bench for tools is to understand the correlations of the single influencing parameters in abrasive processes. The first results of comparative investigations with cooling lubricants of different viscosities are presented and discussed.
The Development of Submarine Pipeline Full-Scale Fatigue Test Machine
Authors: Tang De Yu , Fang Zong Tao , Hu Yan Hua , Niu Hu Li
Published: October 2014

This paper introduces pipeline full-scale fatigue test machine developed by ourselves, including system constitution, main function, mechanical and hydraulic system design, control system development etc. Host framework design and strength calculation, the main technical parameters of the testing machine, working principle and characteristic is highlighted. The development of the fatigue test machine provide a significant basis for research of pipeline fatigue assessment and design, life prediction, also has the important practical significance and broad application prospects.
Fatigue Behavior of Friction Spot Stir Welding with No-Keyhole of Aluminum Alloy
Authors: Wang Xi Jing , Wang Xiao Long , Zhang Zhong Ke , Wang Lei , Zhao Qing Shan , Deng Xiang Bin
Published: October 2014

The fatigue properties of refill friction stir welding joints of 6082-T6 aluminum alloy were completed based on the optimal process parameters. The expression of the fatigue life prediction were obtained in a certain range. The microstructure and fatigue fracture appearance of welding joints were observed and analyzed. And the microhardness of the joints were tested. The results showed that the fatigue crack initiated from the root of the joints between the lower and upper plate, that is the junction of HAZ and TMAZ, and then propagated to fracture along the boundary between the HAZ and the TMAZ. Strengthening phase which was formed of trace elements significantly affected the fatigue properties of spot welding joints. The fatigue life of spot welding joints along with stress intensity factors decrease showed an increasing trend. Fatigue life of spot welding joints emerge an increasing trend along with decreases of the load.
Ferrous Ball-Milled Powders for the Fabrication of Sintered Diamond Tools
Authors: Konstanty Janusz , Romanski Andrzej , Tyrala Dorota
Published: October 2014

The work presents the possibility of application of inexpensive iron-base powders in the production of sintered diamond tools. It has been shown that ball-milled Fe-Ni-Cu-Sn-C and Fe-Mn-Cu-Sn-C powders can be consolidated to a virtually pore-free condition by hot pressing at 900°C. The as-consolidated materials are characterised by a combination of high hardness, mechanical strength and resistance to abrasion. Their properties can be widely modified by changing the milling time.
Influence of Liner Yield Strength on Performance of CNG-II Composite Cylinder
Authors: You Hong Xin , Zhang Shuang , Guo Yang , Liu Run Jie
Published: October 2014

The yield strength of liner material affecting the performance of CNG-II composite cylinder was studied by finite element method (FEM) analysis. The yield strength of liner material 30CrMo was changed from 730MPa to 850MPa with seven strength. The tensile strength of liner material, structural parameters of CNG-II composite cylinder and winding parameters were fixed as the yield strength of liner material changing. The auto-frettage effects of CNG-II composite cylinder became worse and the fatigue life of CNG-II composite cylinder lowered with the increasing of liner yield strength. The yield strength of liner should be lowered to some extent for improving the performance of CNG-II composite cylinder in the production of CNG-II composite cylinder.
Effect of Copper Content on Mechanical Properties of Short Carbon Fiber Reinforced ZrC Mateix Composites
Authors: Cheng Yong , Su Xun Jia , Hou Gen Liang , Shi Zi Liang , Zhong Chong Rong , Xing Ya Kun
Published: October 2014

Cf/ZrC-xCu composite ceramics with different Cu content were prepared by self-propagating high-temperature synthesis/pseudo–hot isostatic pressing (SHS/PHIP). The effect of Cu content on the microstructure and properties of Cf/ZrC composite ceramics were investigated. Our results indicated that carbon fiber was serious chemical damaged in the absent of Cu, accompanied by attenuating of the reinforced effect.Whereas, the density of the complex was increased in the present of Cu content in a dose-dependent-way due to the better fluidity of Cu. Adding to Cu into the complex material leads to the increased diffusion resistance of the elements, decreased damage of the carbon fiber. Meanwhile, the ability of flexural strength manifested as incureasing-decreasing manners according to the elevation of Cu content, while, the fracture toughness was increased gradually. We finally concluded that we could get the best composite ceramic in the present of 25V% of Cu.
Eco-Packaging Solution for Express Service in the Era of Online Shopping
Authors: Zhang Jun Jie , Yang Shan Shan
Published: October 2014

With the development of the internet and the increase in people’s consumption level, online shopping has become increasingly popular with the boom in the online shopping having contributed directly to the rapid development of the whole express industry, which is now experiencing the surge in the business to make the number of the packing bags consumed in the express industry increased at a geometric rate. However at present, the following situations have occurred in Chinese logistical packaging industry: (1) excessive packaging and repeated packaging; (2) the environmental pollution caused by the packing material; (3) the low cyclic utilization rate of the packaging.
Thermal Stability of an Epoxy Adhesive
Authors: Li Mei , Zhao Xiang Yu , Shao Wei , Ma Chuan Bao , Zheng Rui Xue , Chen Ya Dong
Published: October 2014

An epoxy adhesive and its curing agent are tested using differential scaning calorimetry under different atmospheres and after different exposure times to natural air to analyze its thermal properties. The results show that after the pure epoxy, the curing agent and the adhesive mixture of them are exposed in natural air for different period of time, all show different levels of decline in thermal stability and more complicated reactions when tested in the DSC and TGA in O2 and air, while the thermal properties remain stable when they are tested in an inert gas like N2. And according to the mechanical property tests and SEM results, the mechanical properties of the adhesive mixture in N2 are better than that in air. The results indicate that inert gas can protect the property of this kind of adhesive and thus increase its bond strength.
Preparation and Study of EVA/Poplar Wood Powders Composite Foaming Material
Authors: Li Fu Zhi , Ouyang Long , Shi Pu , Wang Lu , Liu Yue Jun
Published: October 2014

EVA/Poplar wood powders composite foaming materials were prepared from etheylen-vinyl acetate-copolymer (EVA) as matrix, poplar wood powders as filler, azodicarbonamide (AC) as foaming agent, dicumyl peroxide (DCP) as cross-linking agent through the method of compression molding foaming. EVA with 15% VA (EVA 15) was chosen as foaming matrix resin by the rotational rheometer. The results showed that an optimum foaming effect had been gained when the AC and DCP were 11 wt% and 0.9 wt%, respectively. And under the condition, the foam density ascended with the increase of poplar wood powders content, when the content arrived to 30%, the resilience reached up to a maximum of 90.1%. The foam cellular structure was researched by SEM, and it showed that when poplar wood powders content was below 30%, the foam holes appeared round or oval, the holes’ size were rather evenly. And the foam cells became more and more unevenly, even collapsed when poplar wood powders up to the content of 40%.
Application Studies on Silane Hydrophobic Agents for Concrete Protection
Authors: Cai Ning , Li Yao Xia , Cui Da Xiang
Published: October 2014

In this paper, the function of silane hydrophobic agents to protect concretes under different varieties and different concentrations were studied. Penetration depth, water absorption ratio and contact angle were measured and compared, the influences of silane hydrophobic agents on the concretes protection under different condition were investigated. Results showed that silane hydrophobic agents exhibit better properties on concretes protection. 24h water absorption ratios of all silane hydrophobic agents surpassed the trade standard JC/T 902-2002 Silicone hydrophobic agent for construction surfaces, and all of the samples showed excellent static water contact angle and hydrophobic property. The protective effect of silane hydrophobic agent B is better than silane hydrophobic agent A.
Optimization of Production Conditions for Activated Carbons from Rice Husk by Potassium Carbonate Using Response Surface Methodology
Authors: Meng Mian Wu , Qi Cong Liang , Liu Qing Ye , Lv Liang , Ai Hao , Zhou Zhen Ming , Zhang Tao , Jiang Hua , Kang Cai Yan , Huang Si Yu
Published: October 2014

A three-factor-three-level experiment was developed by the central composite design (CCD) and Response surface methodology to discuss the effects of concentration of K2CO3, activation temperature and time on the adsorption capacity of the activated carbon (AC) derived from the rice husk and to identify the key preparation parameters. The performance of the AC was characterized by nitrogen adsorption isotherm as Brunauer–Emmett–Teller (BET) and scanning electron microscope (SEM), respectively. The optimal parameters were obtained: Rice husk was soaked in K2CO3 solution (2.32 mol/L) with an impregnation ratio (rice husk: K2CO3=1:3) (wt. %), activated at 1239 K for 0.48 h. The results showed that iodine adsorption capacity of the AC was 1268.52 mg/g, the error between the models predicted (1356.98 mg/g) was only 6.2%. The AC has a large apparent surface area (SBET = 1312 m2/g), total pore volume (0.78 cm3/g) and average pore diameter (11.92 Å).
Overview on Double Ceramic Layer Thermal Barrier Coatings
Authors: Huang Liang Liang , Meng Hui Min , Tang Jing , Li Sen , Yu Ze Qin
Published: October 2014

Thermal barrier coatings (TBCs) system has been the subject of vigorous research over the past decade, driven by the demands for enhanced reliability and substantially higher operating temperature envisaged for the next generations of gas turbine engines. As a novel structure system, the double ceramic layer design is a promising TBCs structure system , especially its long thermal cycling lifetime compared with the single ceramic layer. This paper mainly reviewed of development situation and the existing problems of several mainly double ceramic layer thermal barrier systems, including M-YSZ/YSZ, A2B2O7/YSZ, LTA/YSZ, LnMA/YSZ, ABO3/YSZ and so on. Many challenges remain but healthy and growing collaborations between the science and technology communities bode well for future progress in this area.
Non-Polar ZnO Thin Films and LED Devices
Authors: Li Long , Fang Yong Zheng , Zou Jun , Li Yue Feng
Published: October 2014

ZnO materials have being researched in recent 30 years as a hot topic. ZnO is a third generation of semiconductor, it can be prepared into various forms of films and nanostructures, and they have excellent optical properties, electrical properties and magnetic properties. Because the polar ZnO’s quantum wells have a strong electric field, this will have a great impact on its optical properties. But non-polar ZnO has reduced such a strong electric field, so it greatly improved the luminescent performance. It’s more excellent than polar ZnO in the optical performance. In recent years, non-polar ZnO thin films’ research became increasingly evident. This article summed up the performances, preparations and applications of non-polar ZnO, and there are some suggestions. All of these are good to the further study of non-polar ZnO.
Effect of Methane Concentration on the Performance of Diamond Films Prepared by MPCVD
Authors: Ding Xi Feng , Sun Xin , Wang Wen Jing , Zhang Hong Mei , Gao Hua Na
Published: October 2014

Diamond films were deposited by using methane and hydrogen as the gas source and utilizing the approach of chemical vapor deposition of microwave plasmas on the monocrystalline silicon piece. An analysis was also conducted to investigate the influence of methane concentration on the diamond film. When the methane concentration was set at 0.5%, the experiment turned out to have the high quality diamond film which was dense with homogeneous sizes. In condition that the methane concentration was 2.44%, the film obtained was much denser but with larger proportion of non-diamond components. In case that the methane concentration was about 0.25%, the purity of diamond film was declined while the film was inconsistent.
Loading of siRNA on Magnetic PLL-Fe2O3@SiO2 Nanocomposites and their Transfection In Vitro
Authors: Cui Xue Wen , Cheng Gang , Liu Rui Jiang , Wang Li Wei , Wang Yan Shuai
Published: October 2014

The magnetic Fe2O3 nanoparticles were prepared by co-precipitation method with FeCl3 and NaOH as starting reagents. The surface of Fe2O3 nanoparticles was modified with tetraethyl orthosilicate. Fe2O3@SiO2 nanocomposites were calcined at 600 °C. The nanocomposites were characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDX). The PLL-Fe2O3@SiO2 (SMNP) was prepared by modifying with poly-L-lysine on the surface. The SMNP combined with plasmid siRNA by static electrical charges as one of gene carriers was transfected into SD rat neurons. The results of fluorescence microscope and Prussian blue staining show that SMNP can effectively enter cells. Therefore, SMNP are one kind of novel and effective gene carriers, it can transfect the plasmid which carries the siRNA into SD rats neurons in vitro.
The Influence of Additives on Hydroxyapatite Biological Coatings of Titanium Alloy Substrate
Authors: Wu Sheng Jiang , Shao Hui Ping , Lin Tao , Zhao Zi Fen
Published: October 2014

In this paper, the biological coatings were studied by adding different kinds of additives (TiO2, Al2O3and ZnO) to hydroxyapatite (HA). The different mass ratio of additives and HA in suspension was mixed with n-butyl alcohol as solvent, triethanolamine as dispersant. The HA composite coatings with additives on titanium alloy substrate were prepared by the method of electrophoretic deposition (EPD). The coatings were characterized by scanning electron microscopy (SEM), Ca/P atomic ratio in composite coatings was analyzed by Energy Dispersive Spectrometer (EDS). The results showed that surface of HA coatings was more uniform and dense by adding TiO2than Al2O3or ZnO; and when adding the same kind of additive, the content was higher, there were more holes in HA coatings and surface of the coatings was less uniform. When HA was 15 g/L and TiO2was 5 g/L in suspension, Ca/P atomic ratio was 1.56, that’s the most close to the body's natural bone (~ 1.61). HA coatings can be implanted in the body after a short time of ossification and exhibited a good bioactivity.
Synthesis, Characterizations and Photocatalytic Activity of Mesoporous TiO2 Using Typha Latifolia as Template
Authors: Miao Ying Chun , Chen Guang , Xu Xiao Ling
Published: October 2014

Typha latifolia were successfully used as template to synthesize mesoporous titania and silica with efficient photocatalytic activity under solar and visible light. Both two titania and silica samples were characterized by a combination of various physicochemical techniques, such as, N2 adsorption/ desorption isotherm, diffuse reflectance UV-vis, and X-ray diffraction. It was found that both two synthesized samples exhibited similar morphologies to the original templates. The presence of the residual carbon species of mesoporous titania and silica strongly affects their photocatalytic activity. The photoactivity of P25 TiO2 could not almost exhibit while both mesoporous titania and silica samples exhibited varied photoactivities for dyes under visible light, due to the presence of the residual carbon species. Moreover, as a whole the titania sample enhanced the higher photocatalytic activity than the silica sample under both solar and visible light.
Development of Research and Application of Copper Alloys with High Strength and High Conductivity
Authors: Li Zeng De , Lin Chen Guang , Cui Shun
Published: October 2014

High-strength and high-conductivity copper alloy is a kind of structural function materials, which has excellent comprehensive mechanical and physical properties. The strengthening methods of copper alloy are summarized. The basic requirements of high-strength and high-conductivity copper alloy is established. The application of the materials is described, including lead frame materials, electrified contact wires materials, electrode Materials. Meanwhile, the alumina dispersion strengthened copper alloy is introduced. The internal oxidation process, structure, dispersoid and anti-intenerate properties have also been analysis in detail. Finally, the development direction of this material is put forward.
Effects of Stoichiometric Ratio on the Microstructure and Electrochemical Properties of Ml0.96Mg0.04(Ni0.846Co0.014Mn0.08Al0.06)x (x=5.0-5.3) Alloys
Authors: Guo Hui
Published: October 2014

The as-cast Ml0.96Mg0.04(Ni0.846Co0.014Mn0.08Al0.06)x (x=5.0, 5.1, 5.2, 5.3) hydrogen storage alloys were prepared by vacuum induction melting method under argon atmosphere. Crystal structure, hydrogen absorption, desorption properties and electrochemical properties were investigated by means of XRD, SEM, EDS, PCT (Pressure Composition isotherms) and tri-electrode tests. The XRD and SEM results showed that the alloy were consisted of CaCu5-type phase as the main phase and (Al, Mn)(Ni, Co)2-type phase as the secondary phase. The content of the second phase increased as the stoichiometric ratio increased. PCT results indicated that the amount of hydrogen absorption decreased, while the hydrogen-desorption plateau pressure increased as the stoichiometric ratio increased. The electrochemical test results exhibited that the alloys had excellent activation performance at the second cycle, and the maximum capacity of the alloys were 341.2 mAh/g, 336.5 mAh/g, 333.6 mAh/g, 330.3 mAh/g as the stoichiometric x=5.0, 5.1, 5.2, 5.3, respectively. In addition, the cycle life increased slightly as the stoichiometric ratio increased. ML0.96Mg0.04(Ni0.846Co0.014Mn0.08Al0.06)5.0 had the best performance due to the combine action of trace Mg and stoichiometric ratio.
Property Analysis of Stainless Steel Fiber (Yarn) and its Effect on Knitting Process
Authors: Sun Yu Chai , Cheng Zhong
Published: October 2014

In this paper the frictional and tensile properties of stainless-steel fiber, cotton fiber, polyester fiber and rayon fiber, as well as the tensile and surface hairy properties of stainless-steel yarn, cotton yarn and wool yarn were tested and compared. Experimental results shown that the stainless-steel fiber has greater density, friction coefficient and tensile breakage strength but smaller breaking elongation. On the basis of summarizing the differences between stainless-steel fiber (yarn) and conventional textile fibers (yarns), difficulties occurred during knitting process were analyzed and the corresponding solutions were proposed.
Comparison of Different Methods for Determination of Modulus of Elasticity of Composite Reinforcement Produced from Roving
Authors: Vlach Tomáš , Laiblová Lenka , Chira Alexandru , Novotná Magdaléna , Fiala Ctislav , Ženíšek Michal , Hájek Petr
Published: October 2014

Currently, high performance concrete (HPC) is becoming more and more popular mainly because of its great mechanical parameters. As in the case of ordinary power concrete (OPC) it is necessary to improve the load bearing capacity with using of reinforcement. The present age calls for using of very thin structures for reasons of both environmental parameters and visual quality. Based on this fact, reinforcement start to use durable composite materials, such as technical textiles made of them. Element of HPC with this type of reinforcement is called textile reinforced high performance concrete (TRHPC). It is impossible to use the traditional approach for usually used steel reinforcement if we want to design these extra-thin structures. Modeled structures are very sensitive for input parameters and the development of standards for TRC material lags. The present study is focused on the different method of approach for the determination of tensile modulus of composite reinforcement. Three used methods are compared with each other using numerical analysis of four point bending test of façade element for one type of used reinforcement. Curves from numerical analysis are finally compared with the curve from real experiment and based on this the final evaluation is generated.
Design of Portable Device for Rapid Temperature Testing of Concrete Specimens: System Circuit Design Phase
Authors: Pallegedara Achala , Petřík Martin , Štemberk Petr
Published: October 2014

The project described in this paper is based on sequential development of a temperature controlled weather condition emulator for testing of concrete samples in different temperature levels at varying period of time. The device can be used to test concrete samples when engineer wants to realize the concrete behaviour under extreme conditions such as cold, very high temperature or drastic drops of temperature incurred in a short period and importantly test for concrete samples during hydration. As an initial phase of the development process, entire system architecture is sub-phased to modular form and hence formulated each module for simulation before realizing of the final fabrication of the actual system. The main objective in this phase is to design the electronic circuit to control the attached thermoelectric Peltier which is the main subject of the heat source temperature controller. Since, mathematical modelling of dynamics of the Peltier systems are not well defined and assured to be highly non-linear in behaviour, controlling of the system is driven to be selected by a fuzzy inference engine. Modelling, analysis and simulation of the system dynamics of the Peltier has already been completed in last phase. Design of electronic controller is detailed in the paper with an experimental performance evaluation plot based on extreme loading conditions of the cooling-heating device. Uncertainty incurred in temperature measurements is also provided with experimental data obtained from the proposed system circuit. Characteristics of the proposed emulator are discussed with given significant constrains. Finally, obtained experimental data from the circuit is satisfied with the expected once therefore, this phase can be concluded for developing an optimized fuzzy controller to control the device as final step of the device.
Monitoring of Self Compacting Concrete Characteristics Development
Authors: Křížová Klára , Novosad Petr , Orsáková Denisa
Published: October 2014

The paper presents obtained results of self-compacting concretes with various compositions with focus on basic characteristics development. Firstly the fresh concrete properties are summed and self-compactness classes are categorised and subsequently the values of compressive strength, static and dynamic modulus of elasticity of hardened concretes are compared. All the stated parameters were monitored during different ages of the concrete and therefore they provide a view of its development in time. With still enlarging scale of concrete types and development of their application it is necessary to monitor common parameters which due to the application of new concepts in raw material compositions and use of higher amounts of additives may notably differ compared to applied orthodox concrete parameters.
Study of Correlation Relationships Aerated Concrete Intended for Waterproof Tunnel Lining
Authors: Hubáček Adam
Published: October 2014

The paper focuses on the problems of concrete for watertight tunnel lining. The theme is currently quite topical in the Czech Republic and abroad. The accent is put particularly on determination of level of dependence of different parameters of aeration of fresh and hardened concrete (determined in accordance with standardized procedures in common use) and durability of the concrete based on observation of properties of aerated concrete. Fluctuation of values of air content in hardened and fresh concrete are observed as well as influence of this fluctuation on durability of concrete.
The Capillary Action of Water in the Binder Gels
Authors: Otcovská Tereza , Padevět Pavel
Published: October 2014

Fly ash is a waste product produced during combustion of coal. There are two basic types of fly ash. According to the type of combustion, there is produces pulverised coal combustion (PCC) fly ash or fluidized bed combustion (FBC) fly ash. Use of fly ash additives influences moisture properties of binder gels (cement paste). The particular object of interest of this post is capillary action of water in the binder gels with different concentration of fly ash in the mixture. There are substantial differences among moisture properties of binder gels with FBC fly ash additives compared with the binder gels with PCC fly ash additives.
Comparative Investigations of some Properties Related to Durability of Cement Concretes Containing Different Fly Ashes
Authors: Kubissa Wojciech , Pacewska Barbara , Wilińska Iwona
Published: October 2014

The results of research of mechanical properties and selected other characteristics influencing durability of cement concretes containing cement substitutes were presented. Cement concretes performed with conventional fly ash, fluidised fly ash and their mixture were investigated. The obtained results were compared with findings registered for two types of concrete performed without cement replacements and with cement concrete containing silica fume. The results have shown that cement concrete with predetermined 28-day compressive strength of about 50 MPa and good workability may be obtained using different cement replacements. Generally, these cement concretes exhibited also favorable properties related to concrete durability, i.e. low permeability and sorptivity, and significant reduction of chloride migration coefficient. Favourable results were obtained for cement concrete containing mix of conventional and fluidised fly ashes: good workability, compressive strength after 28th day exceeding 50 MPa, low permeability of water, and low sorptivity, as well as low coefficient of chloride migration. These features were similar as for cement concrete containing silica fume.