bluuebunny/crossref_metadata_2025 huggingface dataset:
A Brief Review on Research Development on Dynamic Behaviors of Carbon Nanotubes
Authors: Mohd Anuar Mohd Afzan , Mat Isa Ahmad Azlan
Published: March 2013

Carbon nanotubes (CNTs) are said to be among the most potential materials in applications of nanodevices, nanocomposites and nanostructure due to their excellent mechanical and physical attributes. CNTs were first discovered by S. Iijima in 1991 where he has reported in his article the synthesis of needle-like tubes by using an arc-discharge evaporation. After the immense discovery, the number of research on CNTs has increased significantly, focusing on their mechanical characteristics, dynamics properties and applications in nanotechnology. This paper attempts to present a review of a quite number of publications on CNTs and their dynamic properties. The main topics covered in this review are the applications of CNTs, their dynamic characteristics including the modeling and simulation of vibrating CNTs, and finally the vibration modes of CNTs.
Dielectric and Structural Properties of RF Magnetron Sputter Grown Lead Zirconium Titanate Thin Film: A Review
Authors: Nurbaya Zainal , Habibah Zulkefle , Rusop Mahmood Mohamad
Published: March 2013

This review summarizes the current state of lead zirconium titanate (PZT) that used for energy storage based organic capacitor. The particular focus is on dielectric material PZT properties for achieving high-k dielectric constant (900-1300) concerning for DC power application. PZT is well known of its perovskite structure that related to excellent ferroelectric properties considered to have high remnant polarization and low coercive field. We review the recent literature that focused on the annealing process that affects dielectric constant and its structural property derived by radio frequency (RF) magnetron sputter.
Diode Characteristics of Zinc Oxide Thin Film at Different Deposition Time for FET Applications
Authors: Salina M. , Sahdan Mohd Zainizan , Yusoff N.A. , Noor U.M. , Rusop Mohamad
Published: March 2013

Zinc oxide (ZnO) is a one of the most interesting compound semiconductors that received more attention during last few years due to its unique properties. Due to that, this study has been done to manipulate those properties to be used for FET applications. The ZnO thin film has been deposited using the thermal chemical vapor deposition. This is done in a double furnace, which vapored the ZnO powder at different temperature. The growth of the ZnO thin film has been observed using SEM and the electrical properties has been analyzed by using I-V probe station. This is done to study the diode characteristics of ZnO thin film to be used in FET applications.
Effect of Different Solvents on the Optical Properties and Surface Morphology of MEH-PPV Thin Films
Authors: Zayana N.Y. , Rusop Mohamad
Published: March 2013

Thin films of poly [2-methoxy-5(2’-ethyl hexyloxy)-phenylene vinylene] (MEH-PPV) prepared from aromatic and non-aromatic solvents were obtained by spin coating techniques. The non-aromatic solvents used are chloroform and tetrahydrofuran (THF), while the aromatic solvents used are toluene and xylene. The UV-Vis and PL spectra of MEH-PPV thin films prepared from toluene and xylene slightly red shift compared to thin films from chloroform and THF. The shifting due to the aggregation formed in thin films. The SEM images of thin films prepared from aromatic solvents shows smooth surface while surface of thin films from non-aromatic is rough. The FTIR spectra of all samples show the same peak assignment of MEH-PPV.
Humidity Sensor Using CVD Deposited SnO2 Thin Film
Authors: Shafura A.K.S. , Md Sin N.D. , Mamat Mohamad Hafiz , Ahmad S. , Rusop Mahmood Mohamad
Published: March 2013

In this paper we address sensitivity of SnO2 thin film deposited by thermal chemical vapor deposition in terms of its behavior towards humidity variations. The structural, optical and electrical properties of SnO2 thin film deposit at different substrate temperature grown by thermal chemical vapor deposition (CVD) are also reviewed. FESEM image reveal smallest particle size of SnO2 at substrate temperature 500°C. Pl measurement shows red shift of SnO2 at substrate temperature 500°C. All thin film performing slightly linear sensitivities towards relative humidity (RH%).
Effect of Sputtering Pressure on Optimization of Titanium Dioxide Nanostructures Prepared by RF Magnetron Sputtering
Authors: Asib N.A.M. , Musa Mohamed Zahidi , Abdullah Saifollah , Rusop Mohamad
Published: March 2013

Titanium dioxide (TiO2) nanostructures were deposited on glass substrate by Radio Frequency (RF) magnetron sputtering. The samples deposited at various sputtering pressures and annealed at 723 K, were characterized using Atomic Force Microscope (AFM) to observe the surface morphology and topology, roughness properties and cross-sectional of TiO2 nanostructures, Field Emission Scanning Electrons Microscope (FESEM) to observe the particle sizes of TiO2 nanostructures and UV-vis spectroscopy to record the UV-vis transmission spectra. The aim of this paper is to determine which parameter of sputtering pressures influence the optimization of TiO2 nanostructures. AFM images show that the surface roughness of the samples decreases as the working pressures of sputtering increases. From FESEM images, it can be deduced that the higher the sputtering pressure, the smaller the particle size is. All the samples are highly transmittance with an average transmittance higher than 80% in the visible region as recorded by UV-vis transmission spectra. The relatively high transmittance of the sample indicates its low surface roughness and good homogeneity. For optimum TiO2 nanostructures deposited at various RF pressures it has the lowest surface roughness and the smallest TiO2 size particles with the indirect optical band gap of 3.41 eV.
Study of Time Effect to the Optical Properties of CdSe Nanocrystal
Authors: Rosmani C.H. , Abdullah Saifollah , Rusop Mohamad
Published: March 2013

The synthesis of Cadmium Selenide (CdSe) by using wet chemical synthesis replace organometallic method. The oleic acid using as the capping agent for CdSe nanocrystals. Paraffin liquid using as solvent for Se and Cd precursor. In this paper, the optical properties at different time was investigated. For optical properties, photoluminescence spectroscopy (PL) was used and for surface morphology field emission scanning electron microscope (FESEM). This paper describe the effect of CdSe properties at different certain time.
Electrical Properties of Nanostructured Aluminum Doped Zinc Oxide (ZnO) Thin Film Prepared Using Sol-Gel Spin-Coating Method at Different Doping Concentrations
Authors: Md Sin N.D. , Mamat Mohamad Hafiz , Rusop Mohamad
Published: March 2013

Aluminum (Al) doped Zinc Oxide (ZnO) thin films were prepared using sol-gel spin-coating method at different doping concentrations. The effects of Al doping concentration at 0~5 at.% on the Al doped ZnO thin film properties have been investigated. The thin films were characterized using Current-Voltage (I-V) measurement and field emission scanning electron microscope (FESEM) for electrical properties and surface morphology, respectively. The I-V measurement result indicated electrical properties of Al doped ZnO thin film improved with Al doping. The FESEM investigations show that the nanoparticles size becomes smaller and denser as the doping concentration increase.
Theory of Nano-Carbon Based Materials: Cyclotron Resonance, Kohn's Theorem and Hubbard Model
Authors: Shrivastava Keshav N.
Published: March 2013

A monolayer of carbon is called graphene. It exhibits unusual properties in the Hall effect and in the cyclotron resonance. It is found that it exhibits fractional charge in the Hall effect. The interactions amongst electrons almost become constant at low temperatures. Hence, the Kohn's theorem, which shows that the interactions do not play much role in determining the cyclotron resonance, becomes operative at low temperatures. The experiments on graphene do not depend on the wave vector dependence of the frequency. Hence whether the dispersion depends on k2 or on k does not matter. The Hubbard model has been very successful in explaining the ground state of several electron systems. We consider a triangle with three vortices. Each vortex can be occupied by two electrons. By using the spin in a particular way, we can obtain new features in the Hubbard model. There is a doubling in the Peierls-Luttinger phase factor and eigen values acquire higher multiplicities than are known for the usual treatment of spin. The flux is distributed on the area of the triangle. The graphene consists of hexagons of carbon atoms but the Hall effect shows that there are defects on which electrons form clusters so that there is spin wave type behaviour. A cluster of electrons shows spin-waves leading to "spin deviation" of several per cent.
Electrical Contact of Au with CNTs Deposited at Different Deposition Temperatures on Silicon Substrate
Authors: Fadzilah Suhaimi Mohd Husairi , Zobir S.A.M , Rusop Mahmood Mohamad , Abdullah Saifollah
Published: March 2013

In this work, the electrical properties of carbon nanotubes were deposited on silicon substrate at different temperatures studied. CNTs were deposited on silicon at temperature 700 to 850 0C by using double-furnace thermal chemical vapor deposition technique. Carbon nanotubes with diameters of 20 to 30 nm were successfully synthesized on a silicon substrate. In this system, carbon nanotubes were grown directly on the p-type silicon. The samples were characterized using field emission scanning electron microscopy and micro-Raman spectroscopy. Based on micro-Raman spectroscopy result, the peak carbon nanotube (around 1 300 to 1 600 nm) was detected. Good electrical contact produced when Au sputter on CNTs characterized by I-V probe. Samples CNTs produced at 850 OC possess good conducting compare to other.
The Process Research on VN-Making which Deploy Vanadium Pentoxide Powder, Graphite and Carbon Black in the Lab
Authors: Ning An Gang , Ding Hua Nan , Ma Jian Jun , Guo Han Jie
Published: March 2013

This paragraph deploys high temperature non-vacuum methods, and vanadium pentoxide powder, carbon black and graphite is used to make VN. The result shows that the particle sizes of these three raw materials vary greatly. When they are mixed with a certain proportion, the kinetics condition of reaction is greatly improved. when the vanadium pentoxide powder enters agglomeration level(1490°C) after it has been reduced and nitrided, agglomeration time has small effect on the reaction process and chemical composition of product. On the contrary，if the agglomeration time lasts too long, it will generate VC. Therefore, the agglomeration time can be reduced to 2~4 hours.
An Enzyme-Catalytic Chemiluminescence Method for Detection of Ethanol Using HAuCl4-H2O2-Luminol System
Authors: Wang Li Sheng , Wang Peng Fei , Huang Shan Shan , Jiang Zhi Liang
Published: March 2013

In pH 8.4 Tris-HCl buffer solutions, the alcohol dehydrogenase (ADH) catalyzed the reaction between ethanol and nicotinamide adenine dinucleotide (NAD) to produce acetaldehyde. The acetaldehyde reduce HAuCl4 to form gold particles, and the excess HAuCl4 have enhancement effect on the chemiluminescence reaction of luminol-H2O2. The excess HAuCl4 decreased when ethanol increased, and the chemiluminescence value decreased. Accordingly we can utilize the chemiluminescence to detect the content of ethanol indirectly. The decreased chemiluminescence value (ΔI) was proportional to the ethanol concentration (C) from 0.017 to 5.10 mmol/L, with a regression equation of ΔI = 2374.3C+280.1, and a detection limit of 2.3 μmol/L. This proposed method was applied to detect ethanol in saliva samples of drunk, with satisfactory results
Biodiesel Production through Direct Transesterification of Microalgae with Alcohol via Ultrasonic Wave
Authors: Kang Yong Feng , Shi Hua Jin , Yang Lin Ge , Kang Jun Xia , Zhao Zi Qi
Published: March 2013

A one-step extraction/transesterification process was developed to directly convert microalgae into biodiesel in the presence of catalyst, KOH using ultrasonic irradiation. The influences of various parameters on the transesterification reaction, including the reaction time, temperature, catalyst concentration, methanol to microalgae mass ratio and ultrasonic power, were investigated. And the optimum conditions for the transesterification process have been obtained as mass ratio of methanol to microalgae as 4:1, catalyst concentration of 7wt.%, temperature as 70oC and ultrasonic power as 100W with an irradiation time of 30 min by orthogonal experiments L9(34 )．Under these conditions, the conversion of fatty acid methyl esters was up to 4.0%.
Effect of Black Carbon in Soil and Sediment on Organic Chemical Sorption and Carbon Sequestration
Authors: Zhang Jing
Published: March 2013

Environmental black carbon (BC) in soils and sediments has received increasing attention due to the sorption for organic chemicals and the potentials for carbon sequestration. In this work, pyrene sorption to humic acid and BC fractions in sediment was investigated by using extracted humic acid and preheated sediment, respectively. Thermally labile organic matter was removed during preheating and the remaining fraction of organic carbon (OC) is recognized as BC. The comparison results highlighted the important role of BC in pyrene sorption, especially at low concentrations. In addition, the micro-porosity of pristine and preheated sediments was analyzed by CO2 sorption. The blocking effect of associated humic substances on the micro-pores of BC for CO2 sorption was not observed. On the contrary, the probed micro-pore volume was higher in the case of pristine sediment, which implies the sorption of CO2 molecules by humic substances.
Research on Performance of Epoxy Electronic Packaging Materials
Authors: Zhou Hao Ran , Sun An , Yang Hao Cheng , Zhao Shuang
Published: March 2013

This article the epoxy resin electronic packaging materials was prepared via epoxy resin E-51 as matrix resin, MNA for curing agent, the CTBN as toughening agents, BPO, DMP-30, Al(MM)3, 2E4MZ as curing promoting agents by mechanical blending. The cured condition was 80°C curing 2 h, 90°C curing 2 h, 100°C curing 5 h. The structure of the epoxy resin electronic packaging materials was characterized via FT-IR, the result showed that epoxy resin cured completely. Dynamic mechanical analysis (DMA) is evaluated material thermal stability. The results show that anhydride dosage 7.7 g. The dielectric loss and volume resistivity of epoxy electronic potting were measured via the electrical performance analysis. The results show that epoxy electronic potting having BPO (0.2 g) and DMP-30 (0.1 g) had electrical optimal performance. In the curing process conditions, its performance is meet potting requirements, curing process is feasible.
Kinetics and Substrates Optimization on a Facultative and Methanotrophic Bacterium
Authors: Zhao Tian Tao , Zhang Li Jie , Zhang Yun Ru , Peng Xu Ya
Published: March 2013

Facultative methanotrophs reported recently could only utilize a few of C2, C3 and C4 compounds, which limited the application of methane oxidation in the engineering of greenhouse gas reduction due to the difficulty of cells propagation. A novel strain, Microbacterium sp. DH isolated from aged refuse, could utilize methane as well as multi-carbon compounds including organic acids and saccharides. Growth characteristics of M. sp. DH were studied with different C6 saccharides as carbon and energy sources, including glucose, mannose, sucrose, lactose, raffinose and starch, and the maximum specific cell growth rates (μmax) were derived using Boltzmann simulation and interpolation methods. The values of μmax were 0.076±0.008 hr-1, which indicated M. sp. DH could be propagated and enriched efficiently with C6 saccharides as substrates. Moreover, after repeated growth on starch or sucrose, a distinguishing characteristic was found that M. sp. DH still could thrivingly grow on methane. In summary, M. sp. DH could be suitable to mitigation of anthropogenic methane emission.
Removal of Chromium from Aqueous Solution by Polymer Enhanced Ultrafiltration Using Copolymer of Maleic Acid and Acrylic Acid
Authors: Mao Lian Jun , Wang Yong Qian , Qiu Yun Ren
Published: March 2013

Polymer enhanced ultrafiltration was used to remove Cr(III) from aqueous solution by using complexing agent, copolymer of maleic acid and acrylic acid (PMA-100), and polyvinyl butyral (PVB) ultrafiltration membrane. Effects of mass ratio of polymer/metal (P/M), pH, added salt and citric acid on the rejection of Cr(III) were investigated. Results show that the rejection of Cr(III) can be 97.2% for 10.0 mg/L aqueous solution at P/M 6.0 and pH 5.0, and the a complete removal occurs when pH is not smaller than 6.0, but the membrane will be fouled due to the formation of hydroxide precipitation at pH 6.0. The addition of the citric acid leads to a significant decrease of rejection while the added salt (up to 0.1M) has little effect on the rejection of Cr(III).
Temperature Dependent Photoluminescence from Polysilsesquioxane Xerogels
Authors: Xu Zou Ming , Wang Yu Xia
Published: March 2013

Polysilsesquioxane xerogels have been prepared via hydrolysis and condensation of the sole precursor N-(3-Trimethoxysilylethyl)ethylenediamine (TMSEEDA) with no acid or base catalyzed sol–gel processing. Complex siloxane matrix is formed along with abundant and covalently linked ethylenediamine (EDA). After high temperature thermal treatment over 500 °C, EDA groups are completely decomposed. The as-synthesized sample exhibits strong blue emission at room temperature (RT), which is shifted to green and red bands when encountered high temperature annealing treatment (in air), promising potential applications in opto-electronics and sensor. Moreover, the PL mechanism is also discussed in details.
The Theoretical Research on Development Direction of Cement Grinding Aids
Authors: Wang Jian Feng , Wang Dong Min , Li Duan Le , Tang Guan Bao , Du Cheng
Published: March 2013

Cement grinding aids has been widely used in cement grinding process. The development of traditional compound cement grinding aids, such as triethanolamine and salts based has encountered a bottleneck. Synthesis of cement grinding aids can be improved by the molecular structure design of traditional cement grinding aids, or even lay aside the shackles of traditional cement additive and synthesize high-grinding effect, high performance and low cost cement grinding aids. In this paper, it has proposed two types of cement additives research direction，medium-small molecule and polymer synthesis system. Finally, it had introduced the application performance advantages of two new synthetic grinding aids, compared to triethanolamine and triisopropanolamine.
Pavement Performance of Hot In-Place Recycling for Waste Asphalt Mixtures
Authors: Ye Ya Li , Zhuang Chuan Yi , Hu Jia Bo
Published: March 2013

With the early asphalt pavements have been into the stage of medium maintenance or overhaul, recycling is a very important way for waste asphalt mixtures. A sample was taken in the expressway from Huhhot to Baotou, and the waste mixtures were extracted from field and sieved; so that the new aggregates can be determined and mix design was carried. With the aid of the penetration, the softening point and the viscosity in 135°C test, the quantity of the regenerant and the asphalt content were ascertained. Through the high temperature stable performance, the anti-low temperature performance, the water stability and the Hamburg wheel-tracking test, the appropriate gradation and the optimum asphalt content were determined. The test results showed that the pavement performance of the waste asphalt mixture was enhanced obviously with hot in-place recycling, and it has achieved technical parameters for old asphalt mixture.
The Removal of Manganese from Underground Water by the Immobilized Manganese-Oxidizing Bacteria
Authors: Zhang Chang Li , Wang Jing Jing , Mei Qing , Yang Hong
Published: March 2013

The manganese-oxidizing bacteria were embedded in polyvinyl alcohol that was cross-linked with boric acid and then processed with glutaraldehyde. The mechanical stability of the immobilized bacteria increased with the concentration of polyvinyl alcohol. The removal rate of manganese increased with the concentration of bacteria only if the bacteria concentration was lower than 1:20(v/v). Adding activated carbon into polyvinyl alcohol had contributed to the development of the mass-transfer, which is benefit to the biological bioactivity, but the mechanical stability would get worse if too many activated carbons were mixed into polyvinyl alcohol. The simulated filter column filled with the immobilized manganese-oxidizing bacteria was cultivated into mature stage which needed about 30 days and the bioactivity of the immobilized manganese-oxidizing was harmed by the toxicity of the cross linking agent and the preparation condition.
Double-Electrode GMAW Welding Process Research Based on the DSC
Authors: Ma Guo Hong , Nie Jun , Zhang Chao Yang , Ye Jia
Published: March 2013

Through a large number of technology experiments, finding out the matching parameters of the DE-GMAW welding of the AZ31B magnesium alloy sheet based on the DSC. This paper simply controls the motor based on the DSC to control the welding torches moving comfortably to make the welding process stable to obtain the good weld.
Synthesis and Aqueous Dispersion of Monodisperse Magnetic Fe3O4 Nanoparticles
Authors: Zhang Wan Ju , Wang Fang
Published: March 2013

Iron oxide (Fe3O4) nanoparticles as one of the most important nanomaterials are suitable for many applications. Monodisperse magnetic Fe3O4 nanoparticles were synthesized by the thermal decomposition of the iron oleate precursor in octadecene (ODE). The iron oleate complex was prepared by reaction between sodium oleic and FeCl3·6H2O at low temperature. The Fe3O4 nanoparticles were transferred from organic solvent into water by amphiphilic copolymer. The aqueous dispersion of Fe3O4 nanoparticles was stable in water and physiological buffers. This method with low cost can be used to prepare large scale of aqueous dispersion of Fe3O4 nanoparticles.
Resonance Rayleigh Scattering Effect of Te Particles and its Analytical Application
Authors: Wang Li Sheng , Liang Ai Hui , Jiang Zhi Liang
Published: March 2013

The Te particles appear two strong resonance Rayleigh scattering peak at 778 nm and 540 nm. In the HCl medium at 70 oC, rhenium (VII) or Re nanoparticles catalyze the Sn(II) reduction of Te(VI) to form Te particles. The RS intensity at 778 nm enhanced linearly with Re concentration. The enhanced RS intensity was linear Re concentration in the range of 0.01-2.0 nmol/L, with a detection limit of 0.005 nmol/L Re. This method was applied to analysis of Re in real sample, and the results were agreement with that of the spectrophotometry
Design of Fuzzy Controllers in AC Servo System
Authors: Zhou Jian Hong , Du Yan , Weng Zheng
Published: March 2013

This paper introduces an ac servo control system that uses permanent magnet synchronous motor (PMSM) as object of control. It combines the feature of permanent magnet synchronous motor and servo-control, and designs the fuzzy self-adaptive of PID controller to achieve control of the position loop, speed loop and current loop. The simulation results of Matlab7.9 show that the controller has an excellent controlling effect.
Study on Intelligent Control of Laser 3D Rapid Prototyping Based on PMAC
Authors: Li Ji , Shi Shi Hong , Fu Ge Yan , Cao Fei , Zhang Yi Shao
Published: March 2013

The paper is based on industrial PC with rich application developed resources under Windows environment and openness of PMAC numerical control system. With the consideration of characteristics and specific requirements of laser rapid prototyping, a third party software is developed by Visual C++ in Windows98 to communicate with the slave machine to get some forming parameters in the laser processing under control by calling PCOMM32PRO DLLs which is offered by Delta Tau company. Combining the developed third party software with the infrared radiation thermometer monitoring the real-time temperature of molten pool can improve the forming efficiency of workpiece obviously.
Entertainment Commercial Space of Lighting Design
Authors: Sun Li Xin
Published: March 2013

The light entertainment commercial space is the most important one of the design content, along with the development of domestic entertainment industry, as well as new lighting technology and application of materials, stylist had the very big imagination space. But the domestic many cases in the design for excessive light new, strange, dazzle, but ignore the basic function of light and energy saving. How to put the lights of the entertainment space design both effect, and can make it function humanization and save energy work, has become a pressing subject. This paper, from the function of the recreational space lighting, decorative lighting, light modelling design and lighting intelligent SPC four aspects are discussed in this paper. Research and to try new lighting design technique, through the application of light source infinite change modelling ability, to improve the environment and our life, so that the entertainment industry to green sustainable development road.
Shearing Edging Investigation in High-Speed Blanking Process Applying Precision Progressive Die
Authors: Huang Zhen Yuan , Ruan Feng
Published: March 2013

The high-speed blanking process applying precision progressive die represents the one of the highest level of today’s stamping technology, mainly is used for the production of the ultra-thin, small, complex electronic components. An orthogonal experiment scheme with three factors (including blanking clearance, surface roughness of the die, stamping speed) was established in this paper based on the actual production. The high-speed blanking process experiment applying precision progressive die was carried out base on this scheme. The quality of the shearing edging of blanking parts was used to evaluate the different influence degree of three factors. The result showed that the surface roughness of the die affected the quality of the shearing edging more than that of the other two. The higher the die surface accuracy, the better the quality of the shearing edging. The result also showed that the high speed can reduce the quantity of the burr of the blanking of the ultra-thin sheet metal.
FEM Analysis of Stress on Shaft-Sleeve Interference Fits
Authors: Shen Jian , Chen Dong , Liu Guang Fu , Zhou Dan , Du Xiao Dong
Published: March 2013

Interference fit is one of the principal difficulties during Remanufacturing. Research on shaft–sleeve interference fits stress characteristics and influencing factors are very important for the study on remanufacturing disassembly method. Different interference, shaft diameter, wall thickness and mating length are taken into account and various FEM contact analysis calculations were carried out by orthogonal test. The relationship between influencing factors and contact stress were also investigated with the stepwise multiple regression analysis, optimum regression equation was established and analyzed by response surface method. The analysis result shows that interference is the most significant factor that affecting the contact stress
Analysis on Insulation Resistance Performance in Airport Lighting Circuit
Authors: Dong Hui Fen , Gao Qing Ji , Liu Jian Shan
Published: March 2013

The airfield lighting circuits are the important part of the airfield lighting system, and the insulation performance of the circuits directly affects the aircraft flight safety. The side insulation performance of the lighting circuit and the effect of the temperature and humidity on the insulation are analyzed in the paper. Depending on the measure data provided by the Shanghai PUDONG international airport, the curve of circuit insulation resistance changed with the time is fitted through computer, and the insulation resistance mode based on the parameter identifying is obtained. The theoretical foundation is laid for the forecast decline of insulation resistance, and a theoretical basis is provided for the maintenance of the lighting circuit.
Electromagnetic Performance Analysis of Claw-Pole Alternator with Changing Permeance
Authors: Bao Xiao Hua , Liu Mou Zhi
Published: March 2013

A changing air gap permeance model of the alternator and its influence were discussed in this paper. When the alternator was under high-speed operation, taking it into consideration that the claws getting deformation for rotating centrifugal force and electromagnetic exciting force, the alternator’s changing air gap permeance model was established. And the alternator’s Maxwell3D calculation model was built. The field magnetic distribution under the rated speed was obtained as well, also before the claws’ deformation was obtained. The harmonics of the air-gap flux were analyzed and compared. The changing air gap permeance model was proved to be reasonable. It would lead to air-gap magnetic field distortion of the generator, which affected the generator’s electromagnetic properties. Instruction was provided for more precise of air gap magnetic field analysis or vibration noise analysis of alternator.
Coupled Heat Transfer Analysis of Interlayer Active Cooling Barrel of Large Caliber Gun Based on CFX
Authors: Peng Song Jiang , Wang Xiao Hui , Yu Cun Gui
Published: March 2013

Large caliber naval gun weapon system in sustained and rapid firing process, produced high temperature and high pressure gas will form pulsed high temperature flow in barrel, causing the barrel being heated and cooled sharply and then being in bad environment, affecting the life of the barrel. The research object of this paper is based on 155mm naval gun, to utilize the theories of fluid mechanics and heat transfer and use ANSYS-CFX software, to simulate the heat response of the gun’s rifling original portion under interlayer active cooling, and to analyse the effects of structure parameters of interlayer cooling system and flowing parameters of cooling liquid on cooling performance using the principle of heat transfer enhancement, providing guidance for the optimization of the structure of the interlayer cooling system.
Mechanical Characteristic Study of the Roller Forks' Main Girder Using Different Materials
Authors: Feng Xiao Mei , Duan Xiu Bing , Lu Xue Cheng , Li Yu Lan
Published: March 2013

Using the novel rollers mechanism, a new Roller Forks is put forward. As the key component of the forks, the main girder’s strength is studied in detail. According to adopting different materials, its maximum distortion and stress are analyzed. The analysis results can be used as the base of the material selecting of the main girder.
A Novel Interior Ballistic Prediction of Gun Propellants Based on Experimental Pressure-Apparent Burning Rate Model in Closed Vessel
Authors: Xiao Zheng Gang , Ying San Jiu , He Wei Dong , Xu Fu Ming
Published: March 2013

A new experimental pressure-apparent burning rate model was established based on the recorded pressure-time data in the closed vessel to study the actual burning gas generate rate of a propellant whose form function is not available. The new burning model can replace the Vieille’s law and form function of propellants in the interior ballistic equations to predict the interior ballistic performance of gun. As distinct from the traditional geometric form function based burning rate model, the new model introduced the concept of relative pressure impulse related to the actual burnt web thickness of propellant statistically. The apparent burning rate was expressed by the propellant mass fraction burnt vs. relative pressure impulse curve. The interior ballistic simulation of selected gun propellants was conducted using the new burning rate model. The results predicted by the new model show a good agreement with the classic interior ballistic predication results though the agreement with the experimental results is still to be improved.
The Multiaxial Creep Strength Analysis Coupling with Damage Evolution for 3D Innercasing of the USC Turbine System
Authors: Mao Jian Feng , Zhang Jun Hui , Wang Wei Zhe
Published: March 2013

Information revealed from 3D thermal-mechanical simulations of the innercasing over 0.2 million hours by finite element method(FEM) provides detailed local distributions of stress, temperature, and creep damage through the whole configuration. It found that the innercasing of a Ultra-supercritical(USC) turbine is subjected to the complex stress states. Due to this, the multiaxial effect is considered in the creep damage analysis.
On Determining Elastic Modulus from Instrumented Indentation
Authors: Huang Shuai , Yuan Huang
Published: March 2013

Computational simulations of indentations in elastic-plastic materials showed overestimate in determining elastic modulus using the Oliver & Pharr’s method. Deviations significantly increase with decreasing material hardening. Based on extensive finite element computations the correlation between elastic-plastic material property and indentation has been carried out. A modified method was introduced for estimating elastic modulus from dimensional analysis associated with indentation data. Experimental verifications confirm that the new method produces more accurate prediction of elastic modulus than the Oliver & Pharr’s method.
PZT / MWNTs / EP Piezoelectric Damping Composites Conductivity and Dynamic Mechanical Analysis
Authors: Zang Chong Guang , Cao Xian Peng
Published: March 2013

According to piezoelectricity and electrical conductivity theory, the ternary system piezoelectric damping composites containing piezoelectric ceramic powder (PZT) / multi-walled carbon nanotubes (MWNTs) / epoxy resin (EP) were developed. Through the conductive and mechanical performance test of composites, the paper showed the piezoelectric damping energy dissipation mechanism of polymer composites. Results indicated that: the loss factor of materials would increase with the increasing of PZT content. When the content of PZT exceeded a certain value, tanδ would increase dramatically. When the content of MWNTs is 2%, tanδ reached a high value. This meant composites played the role of shock absorbing by conducting electricity from piezoelectric effect of PZT to external circuit.
The DC-Bias-Superposition Characteristics of Low Sinter Temperature NiCuZn Ferrite
Authors: Yan Shuo Qing , Li Qi Fan , Dong Li , Feng Ze Kun
Published: March 2013

The DC-bias superposition characteristics of NiCuZn ferrite with different amount of Bi2O3 have been investigated. The microstructure depends much on the amount of Bi2O3. The DC-bias-superposition characteristics have great relationship with the microstructure. The permeability of materials composed of tiny grains decreases more slowly with the increase of DC-bias superposition due to the absence of the domain walls in the grain. The nonmagnetic phase in the grain boundary can reduce the actual DC-bias superposition in the grains when the sample was subject to DC-bias superposition. In short, a microstructure with relatively small average grain size and thick nonmagnetic phase in the grain boundary, which is favorable for obtaining better DC-bias superposition characteristics.
Research of Micropore Electric Spark Machining Based on Hymu 80 Soft Magnetic Alloy Material
Authors: Ma Jun , Xiong Yue Dong , Cheng Li
Published: March 2013

The paper studies micropore electric spark machining of Hymu 80 soft magnetic alloy materials focusing on the influence of gap voltage on the processing to commence the experiment and analyze experimental results. It also discusses the influence of gap voltage on electrode consumption length, the diameter difference of inlet and outlet and reaming amount, find the optimization matching between peak point current and gap voltage, and proposes the idea of improving micropore process.
Study on Preparation and the Noise Suppression Effect of Co2Z Ferrite Films
Authors: Li Qi Fan , Yan Shuo Qing , Zeng Yi , Feng Ze Kun , Wu Jie , Li Hui Wen , Peng Liang
Published: March 2013

The Co2Z ferrites noise suppression sheet was prepared by tape casting. Its microstructural characterization was performed by electron microscopy and noise suppression effect was measured by a microstrip line method. Results indicate that as the sinter temperature increases, the imaginary permeability increases leading to the enhancement of the suppression capability, and the thickness of noise suppression sheets also contribute to the noise suppression capability.
Low RCS Antenna Based on EBG Structure
Authors: Gao Qiang , Tan Fen , Sun Jun
Published: March 2013

In this paper, the application of stealth materials based on EBG structure in radar antenna system is studied. This materials is thinner and weaker, and can be well integrated with waveguide antenna. Radar cross section (RCS) is reduced effectively and stealth is realized.
A New Method of Directional Solidification of Cu-Cr Alloy
Authors: Li Lan , Li Lin Sheng , Qiu Chang Jun
Published: March 2013

In order to meet the need of high-strength and high-electrical conductivity copper alloys in industry. A method of making high-strength and high-electrical conductivity copper alloys is discussed in this paper. This method uses the technology of heated mold continuous casting to make Cu-Cr alloy. Because it utilizes the high electrical conductivity of copper matrix and high strength of the chromium phase, the in-situ composite Cu-Cr alloy with directional solidification structure is got. The in-situ composite Cu-Cr alloy has good properties and will be widely used in industry.
Study on Corrosion Behavior of Ti-Ni-Nb Shape Memory Alloy and 1Cr18Ni9Ti Stainless Steel Aeroplane Pipe System
Authors: Shi Jun Xiu , Liu Jian Hua
Published: March 2013

The susceptibility to stress corrosion cracking (SCC) and galvanic corrosion of an aeroplane pipe made of 1Cr18Ni9Ti connected with a pipe coupling that made of Ti-Ni-Nb shape memory alloy were evaluated. SCC test was completed under simulated service environment in 6% NaCl solution through a self-designed corrosive system. Galvanic corrosion behavior of Ti-Ni-Nb/1Cr18Ni9Ti couple was conducted in 3.5% NaCl solution at 30°C, in which galvanic corrosion current (Ig) and galvanic corrosion potential (Eg) were monitored. The corrosion morphology was observed by using scanning electronic microscope (SEM) and optical microscope (OM) after SCC test and galvanic test. It was showed that no obvious corrosion was detected on the surface of the whole pipe system after the simulated test. The two metals showed excellent resistance to SCC based on the section morphology observation. The average galvanic corrosion current of 1Cr18Ni9Ti/Ti-Ni-Nb couple was 0.13µA/cm2. No obvious corrosion pitting was detected on the surface of the two alloys by OM observation. Therefore, 1Cr18Ni9Ti pipe was safely connected with Ti-Ni-Nb pipe coupling in aeroplane pipe system.
Review of Status about the Effect of Ultrasonic Impact on Fatigue Properties of Welded Joints of Magnesium Alloy
Authors: Yu Ying Xia , He Bo Lin , Wang Bin , Zhou Shang Yu
Published: March 2013

The study on magnesium alloy has attracted attention at home and abroad. Status and development trend about the fatigue properties of welded joints of magnesium alloy were reviewed. The main problems and deficiencies were pointed out, and the recent development's focus was outlined. The development trend of improving the fatigue propeties and fatigue life was analyzed. The ultrasonic impact method can not only decrease the stress concentration coefficient and tensile residual stress of welded joint, but also refine the grain size of welded joints, even to compressive stress and nanograins. The method has put forward a new way for increasing fatigue properties and life of welded joint of magnesium alloy.
Transformation Behavior of Austenite Continuous Cooling of Nb-V Micro-Alloyed Low Carbon Steel
Authors: Bao Jun Cheng , Ma Jun Xing , Zhao Jie , Ning Bao Qun
Published: March 2013

The transformation behavior of Nb-V micro-alloyed low carbon steel during continuous cooling was studied through thermomechanical simulator and metallographic analysis. The results show that the dynamic CCT diagrams shift to the left and upper compared with the static ones, the begin temperature of γ→α transition is gradually lower with the increase of cooling rate. The high temperature deformation decreases Ferrite transition zone. When the cooling rate is lower, the deformation improves Bainite transition; when the cooling rate is higher, the deformation inhibition Bainite transition.
Effect of Process Parameters on Temperature Field during Laser Sintering of 316L Stainless Steel Powder
Authors: Ren Nai Fei , Wang Dian , Jia Lei , Ge Xiao Bing
Published: March 2013

Finite element analysis software ANSYS is a platform, Using the Parametric Design Language of APDL language to write programs to simulate the temperature field of the laser sintering of 316L stainless steel powder. Building the model of Finite element analysis to analysis the simulation's various difficulties, such as the thermal parameters at different temperatures, the loading of the heat flux and some of the key parameters. Researching the affect of laser power and scanning speed on the temperature field, it’s valuable in researching the temperature field of the metal powder sintering
Compatibility and Crystallinity of Electrospun Aligned PHBV/PEG Ultrafine Fibers Scaffolds
Authors: Shao Mei Ling , Yang Qing , Chen Lu
Published: March 2013

Aligned PHBV/PEG ultrafine fibers are fabricated for potential applications in tissue repair. In this paper we find that the optimum spinning parameters to prepare aligned PHBV/PEG fibers is as follows: the concentration of 8wt%, voltage at 10kv, receiving distance at 18cm, the boost speed at 0.8ml/h and the best linear velocity of the rotating drum at 9.5m/s. The content of PEG is less than 50%. In addition, we investigate the interaction between PHBV and PEG in its entirety; we also discuss the surface morphology of the blends, compatibility, thermal decomposition and crystallization behavior by the help of different test methods.
Experimental Study on Heat Transfer Boundary Conditions for Steel Hot Extrusion Process
Authors: Liu Chang Yong , Zhang Lei , Kang Fei Yu
Published: March 2013

Heat transfer boundary conditions have significant influence on the FEM analysis of the steel hot extrusion process using glass lubricant. However, the determination of heat transfer coefficient between billet and tooling lacked experimental basis. In order to obtain rational values of the coefficient, experimental study was conducted to measure it on thermal contact between P92 steel and H13 steel separated by glass lubricant. The influence of contact temperature, contact pressure and lubricant thickness was investigated. The obtained results can provide experimental basis for the determination of heat transfer boundary conditions for steel hot extrusion.
Preparation and Performance Evaluation of Chitosan Local Medicine Composite Membrane Material
Authors: Guo Lan , Zhao Zhi Yu , Zhao Xin , Bai Jing , Han Shu Ying
Published: March 2013

This study uses natural polymer polysaccharide chitosan as film material, and prepares Quercetin-chitosan oral ulcer composite film in order to improve permeability of the drug to ulcer position reaching the delay-releasing effect. we uses this film in the oral ulcer animal model to verify its curative effect and discuss its mechanism in order to lay the foundation for further clinical application.
The Bioactivity of Gradient Composite Bioceramic Coating with La2O3 Fabricated by Wide Band Laser Cladding
Authors: Liu Qi Bin , Yang Bang Cheng
Published: March 2013

To improve the quality of bioceramic gradient coatings, wide band laser cladding technique was adopted to produce a kind of gradient composite bioceramic coating, which combines the good biocompatibility of HA and β-TCP with good toughness and strength of TC4 alloy. The rare earths oxide La2O3 was added to improve the properties of the bioceramic coating. The results indicate that when the adding of La2O3 is 0.6wt%, the ceramics coating is of the largest amount of HA and β-TCP catalyzed, and the number of cells proliferated and the ALP secreted on coatings is the biggest, which indicates that the biocompatibility and bioactivity of gradient bioceramic coating is the best. The biocompatibility and bioactivity are closely related to the amount of HA and β-TCP catalyzed by La2O3.
Dynamic Mechanical Properties of Trimethylborate (TMB) Modified Poplar Wood by Sol-Gel Process
Authors: Wang Chang , Zhang Wen Bo , Cheng Yun
Published: March 2013

To develop novel wood preservation technique trimethylborate(TMB) and boric dioxide were used by sol-gel process to modify poplar (Populus euramevicana cv.‘I-214'.) wood. The temperature variations of the storage modulus and the loss tangent along the grain for two kinds of chemically modified poplar woods were measured at 2Hz over a temperature range of -50 to 200°C. The storage modulus of modified woods were observed slight increases over the temperature range tested by introduction of bulky side chains and the tanδ remarkably reduced due to boric acid bridges between the hydroxyl groups which restricted the micro-Brownian motion of the main chains. In TMB treatment, peak width at half height of tanδ broadened significantly, indicating remarked cross-linking effect in polycondensation with wood cellulose.
Preparing Technology of Porous Hydroxyapatite/Chitosan Bioceramics
Authors: Wang Feng , Sun Li Wei , Shen Jian Xing , Zhao Ping
Published: March 2013

Hydroxyapatite/Chitosan bioceramics were fabricated by combining in-situ chemical synthesis and freeze drying method, using (NH4)2HPO4, Ca(NO3)2·4H2O, and chitosan(CS) as raw materials. The effect of solid loading and freeze-drying time on microstructures of hydroxyapatite/Chitosan bioceramics was studied. The microstructures of the fabricated porous bioceramics were investigated by means of X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results showed that the hydroxyapatite/Chitosan bioceramics have interconnected porous structures from several microns to 200um, more suitable to bone tissue implantation. In addition, the porous structures are affected solid loading of slurry and freeze-drying time.
Synthesis and Electrorheological Properties of SiO2/Polyaniline Nanocomposites Prepared by In Situ Polymerization
Authors: Wang Ting Ting , Liu Xue Hui , Guo Jian Jun , Cheng Yu Chuan , Xu Gao Jie , Cui Ping
Published: March 2013

SiO2/polyaniline (PANI) nanocomposites were obtained by chemical oxidative polymerization using ammonium peroxydisulfate as oxidizing agent. The FE-SEM and TEM images showed that nanocomposites presented the core-shell structure with raspberry morphology. The electrorheological (ER) effect of those materials was enhanced by using the ammonium hydroxide to deprotonate the corresponding PANI base. It was found that the yield stress of those ER fluids and its near linear dependence on the electric field were different from the conventional ER fluids.
Lattice Vibration, Heat Capacity and Vibration Entropy of Single-Layer Hexagonal-BN
Authors: Zhao Man , Ma Fei , Zheng Hai Bing , Yang Dong , Xu Ke Wei
Published: March 2013

Abstract. The phonon spectrum of zigzag h-BN nanoribbons with the edges passivated by hydrogen atoms under tensile strain along the axis direction were calculated by ﬁrst-principle calculations. It is found that the uniaxial strain can lead to a narrow frequency range of lattice vibration modes. But it hardly affects the two highest frequency modes due to the vibration of B-H or N-H bonds. In particular, the strain usually promotes the softening of phonon modes. It means that more phonons should be activated at a given temperature. This may result in the changes of thermal properties, such as, heat capacity and vibration entropy.