bluuebunny/crossref_metadata_2025 huggingface dataset:
DVT Grown GeSe Single Crystals and their Thermal Parameters in N2
Authors: Patel Ruchita R. , Solanki G.K. , Gosai N.N. , Patel Rahul B.
Published: March 2013

Most of the applications of semiconductors involve either photon absorption to form free carriers (photodetectors or solar cells) or the formation of photons by free carrier recombination (light emittiing diodes or lasers). Both kinds of applications require high quality single crystals having desirable dimensions, devoid of defects, grain boundaries, or impurities that act as electron scatterers, traps and non radiative recombination centers. As a consequence of the requirement of high quality, fabrication and growth conditions for the semiconductors must be carefully controlled for most applications. Hence single crystals of GeSe were grown by Direct Vapor Transport (DVT) technique, in a two zone horizontal furnace with temperature difference of 50 K between growth and source zones. The material crystallizes in the form of shining gray and platelets like crystals at the end of growth cycles. Thermogravimetric analysis (TGA) has been used for many years to evaluate thermal stability of material as it will determine the range of stable operation for a device made up out of these materials under investigation. Thermal characteristics of GeSe crystals were studied employing thermoanalytical techniques, viz. TGA and DTA. Thermal analysis experiments were carried out with constant heating rate of 10 °C/ min in N2. The objective of this study is to determine activation energy and other kinetic parameters of GeSe crystals. Broido and Coats-Redfern (C-R) methods are used to evaluate different kinetic parameters of GeSe crystals viz. activation energy, entropy, enthalpy, Gibbs mean free energy etc.
Nanotoxicity of Magnesium Oxide on Human Neuroblastoma SH-SY5Y Cell Lines
Authors: Hasbullah N.I. , Mazatulikhma Mat Zain , Kamarulzaman N.
Published: March 2013

The use of magnesium oxide (MgO) nanoparticles in industrial applications has been raised over the last decade. However, there is limited toxicology information available regarding the effects of MgO nanoparticles. In this study, cytotoxicity and neurotoxicity of this nanoparticle on SH-SY5Y cell lines was investigated. In order to assess the cytotoxicity effect, SH-SY5Y cells were exposed to three different types of MgO nanoparticles (MgO 5, MgO 10 and MgO 24) for 24, 48 and 72 h. The concentration of nanoparticles ranges from 1nM to 1mM. Cell viability was determined by MTS assay. Neurotoxicity test was performed to determine the effects of MgO nanoparticles on human neural cells. Results indicated that MgO nanoparticles are not toxic to both undifferentiated and differentiated SH-SY5Y cells. With further exploration, the safety and health concern regarding exposure of MgO nanoparticles can be verified since the increasing of using this nanoparticle in industry over the time.
Graph and its Computer Application with C++ Using Linked Lists
Authors: Shrivastava Akash
Published: March 2013

An effort is made to develop a computer programme using C++ to explain the working of a adjacency linked-list representation of a directed graph or digraph and explain the allocation of data using C++. The program uses the concept of arranging a graph in the form of a linked list for the computer to understand the graphical form representation of any data. The graph algorithms are a significant field of interest within computer science. Typical higher level operations associated with graphs are; finding a path between two nodes, like depth-first search and breadth-first search and finding the shortest path from one node to another, like Dijkstra's algorithm. A solution to finding the shortest path from each node to every other node also exists in the form of the Floyd-Warshall algorithm. A directed graph can be seen as a flow network, where each edge has a capacity and each edge receives a flow. The Ford-Fulkerson algorithm is used to find out the maximum flow from a source to a sink in a graph. Conversion of a graph into a computer storable digital data is useful for nanodevices.
Mechanical and Morphological Properties of Tropical Wood Polymer Nanocomposite (WPNC)
Authors: Islam Md. Saiful , Hamdan Sinin , Rusop Mohamad , Rahman Md. Rezaur
Published: March 2013

A novel route to wood modification by impregnation of nanoclay combined with phenol formaldehyde (PF) resin is developed in this study. Wood polymer nanocomposites (WPNCs) were prepared from several tropical wood species by impregnating the woods with PF/nanoclay formulations. The vacuum-pressure method was used to impregnate the samples with PF/nanoclay prepolymer mixture. The formation of wood polymer nanocomposites and the location of impregnated materials inside wood were confirmed through SEM image and XRD pattern respectively. The PF/nanoclay loading achievable was found to be dependent on the properties of wood species. Low loading was observed for the high density wood species. Mechanical strength of fabricated WPNCs in terms of modulus of elasticity (MOE) was found to be significantly improved. Furthermore, morphological properties of raw wood and WPNC samples were evaluated by scanning electron microscopy (SEM) and XRD analysis and a change in morphological properties was also observed for WPNC.
Synthesis of Carbon Nanotubes by Chemical Vapour Deposition of Camphor Oil over Ferrocene and Aluminum Isopropoxide Catalyst
Authors: Salifairus M.J. , Rusop Mohamad
Published: March 2013

The aim of this study is to engage a basic understanding of the information carbon nanotubes (CNTs) may yield when this CNTs is deposited on silicon substrate over ferrocene and aluminum isopropoxide catalyst. Several popular methods are used to produce high quality CNT such as chemical vapour deposition, arc discharge and others. Most promising method is, chemical vapour deposition (CVD), used to produce CNTs in this experiment. The carbon source and catalyst were placed at different alumina boat in furnace one (1). The silicon substrate was placed at the deposition furnace and range temperature from 700 oC to 900 oC. The G-band peaks of the CNTs appear at round 1580 cm-1 and D-band peaks appear at 1348 cm-1. Thermal analyses show the percentage of CNTs weight loss 75.12%, 86.39%, 86.54%, 87% and 92.3% respectively. FESEM images was observed to study the formation of the CNTs. The CNTs were successfully synthesized from the chemical vapour deposition method.
The Effects of Inoculum in Fermented Glutinous Rice for Nanotechnology Applications
Authors: Nik S.F. , Zainal N.F.A. , Azira A.A. , Mohamed F. , Abdullah Saifollah , Ahmed A.Z. , Rusop Mohamad
Published: March 2013

Carbon nanotubes (CNTs) were unique nanostructured materials composed of single or multiple rolled graphene sheet which usually need expensive sources as a starting material in its preparation. In this paper, new approach of starting material was expected to be commercialized due to its cheaper and renewable properties. Fermented glutinous rice would be optimized before it can be used as starting material in the CNTs preparation. In optimizing the process, a few parameters were considered. One of the important parameters was the amount of inoculums; known as ‘ragi’. This paper showed the effect of inoculums using Fourier Transmission Infrared Spectroscopy (FTIR). The amount was varies depending on percentage of glutinous rice used in the process. The optimum amount of inoculums for nanotechnology application was 3.0% (w/w) of glutinous rice due to the most favorable level of glucose and alcohol after 3 days fermentation. The glucose level decreased whereas alcohol yield was raised when higher inoculums amount were used. The result suggested that sample with inoculums amount of 3.0% (w/w) glutinous rice was the best starting material for nanotechnology application.
Relation of Anodisation Parameter for Nanocrystallite Size of Porous Silicon Template Studied by Micro-Raman Spectroscopy
Authors: Asli N.A. , Rusop Mohamad , Abdullah Saifollah
Published: March 2013

Nanostructured porous silicon templates (NPSiT) were prepared by photo-electrochemical anodization of p-type crystalline silicon in HF electrolyte at different etching time. Two set anodisation parameter were observed, anodisation time nd current density applied. For set one, five samples were prepared with etching time varied from 10 to 50 minutes at 20 mA/cm2 of current density. For set two, five samples were prepared with current density varied from 5 to 40 mA/cm2 for 30 minutes. The effects of these anodisation parameter on NPSiT were observed based on nanocrystallite size. These studied was demonstrated by Raman spectroscopy. It was found that NPSiT sample with large pore diameter, which is smaller nanocrystallites size of Si between pore.
Zinc Oxide Nanorods Characteristics Prepared by Sol-Gel Immersion Method Immersed at Different Times
Authors: Awalludin M. , Mamat Mohamad Hafiz , Sahdan Mohd Zainizan , Mohamad Z. , Rusop Mohamad
Published: March 2013

This paper focus on zinc oxide (ZnO) nanorods prepared using sol-gel immersion method immersed at different time. Immersion times have been varied 1~24 hr and the characteristics of each sample have been observed. The effects of immersion time on ZnO nanorods thin films have been studied in surface morphology and structural properties using Scanning Electron Microscopy (SEM) and X-ray diffractometer (XRD), respectively.
Characterization of Copper (I) Iodide (CuI) Thin Film using TMED for Dye-Sensitized Solar Cells
Authors: Zainun A.R. , Mamat Mohamad Hafiz , Noor U.M. , Rusop Mohamad
Published: March 2013

Solid state dye-sensitized solar cells (DSSCs) were first reported in 1991 without employing p-type as hole conductor. The p-type as hole conductor was first introduced in 1995 and CuI is preferred among others p-type semiconductors. However, in 2003 utilizing of CuI based DSSC was found unstable by the excessive iodine strongly decreased the photocurrent of the cell. Later then, the stability of CuI based DSSCs was reported can be improved by added small amount of triethylamine hydrothiocyanate (THT) in the CuI coating solution. Following to that, in this work new chemical is introduce as an option to present situation which can give equally or better effective for fabrication of solid-state DSSCs. The chemical is called tetramethylethylenediamine (TMED), is employed to CuI in sol-gel process and their characterizations have been studied. The CuI coating solution was prepared by dissolved CuI powder with acetonitrile and added in 0.5mL TMED. Using spin coating technique the sol then deposited onto glass and silicon substrate at room temperature. The film were analyzed by their particles conductivity using pH meter, surface morphology using Field Emission Scanning Electron Microscope (FE-SEM) and optical properties using ultraviolet visible spectroscopy (UV-Vis) and photoluminescence (PL) measurement. The results of this sol-gel were compared with other CuI sol-gel which prepared by dissolved CuI powder with acetonitrile only. The optical transmittance within ultra-violet range exhibited that thin film is transparent and it optical band gap have been studied. Further clarification and measurements need to be done in order to prove that the proposed chemical can be used as an option.
Surface Morphology and Compositional Analysis of Undoped Amorphous Carbon Thin Films via Bias Assisted Pyrolysis-CVD
Authors: Ishak A. , Dayana K. , Rusop Mohamad
Published: March 2013

Amorphous carbon (a:C) were successfully deposited on the silicon surfaces via bias assisted pyrolysis-CVD in the range between 350oC to 500oC with constant of negative bias -50V in 1 hour deposition. The heated of palm oil at about 150oC was vaporized then used for deposited onto p-type silicon substrates. The deposited thin films were characterized by using field emission scanning electron microscopic (FESEM), energy dispersive analyser x-ray (EDAX). We have found carbon element at about 0.15 keV from EDAX with surface morphology formed a nano-ball like structure at 450oC of palm oil precursor. These results indicated deformation of physical and structural thin films caused by applied negative bias and the temperature.
Comparative Study of P-Doped and Undoped ZnO Nanostructures Using Thermal Evaporation and Vapor Transport Method
Authors: Al-Azri Khalifa , Md Nor Roslan , Mohd Amin Yusoff , Al-Ruqeishi Majid S.
Published: March 2013

We report the synthesis of phosphorus-doped (P-doped) and undoped ZnO nanostructures using a thermal evaporation and vapor transport on Si(100) substrate without any catalyst and at atmospheric argon pressure. The structural and optical properties of P-doped ZnO nanostructures and undoped ZnO nanostructures have been extensively investigated using filed emission scanning electron microscopy (FESEM), X-ray diffraction (XRD) and Photoluminescence (PL). FESEM observation reveals that the morphology of ZnO nanostructures was changed from a hexagonal-like shape to a spherical shape when doping with P. While, XRD results indicate that P-doped ZnO nanostructures lost the (002) orientation preference and became randomly oriented. In addition, shifting of (002) diffraction peak has been found due to the incorporation of P into ZnO. Room temperature (PL) spectrum of P-doped ZnO nanostructures shows a high efficiency of green emission which was attributed to the presence of phosphorus atoms in the ZnO nanostructures.
Computational Study on Triphenylamine-Based Dyes Containing Benzimidazole Units for Dye-Sensitized Solar Cells
Authors: Wan Zhong Quan , Zhou Lin Lei , Jia Chun Yang , Yao Xiao Jun , Shi Yu
Published: March 2013

Three novel dyes (D1, D2 and D3) containing triphenylamine (TPA) unit as core and bearing different benzimidazole units as secondary electron-donors are designed. The geometries, electronic structures, and electronic absorption spectra of these dyes are studied by DFT and TD-DFT. The optimized results indicate that these dyes are all non-coplanar, which can help to inhibit the close intermolecular π-π stacking aggregation effectively. The lowest unoccupied molecular orbital (LUMO) energy levels of the dyes are higher than the conduction band edge of the TiO2, which ensures a high efficiency of electron transfer from these dyes to TiO2 electrode. As the highest occupied molecular orbital (HOMO) energy levels of these dyes are lower than those of I-/I-3, these molecules that lose electrons could be restored by getting electrons from electrolyte. The absorption spectra of these dyes are simulated, and the calculated results indicate that D3 can absorb more photons than those of D1, D2 and TPAR in the region from 250 to 580 nm, which should have the best performance of photo-to-electric conversion efficiency.
Preparation of Cryolite from Industrial Grade Sodium Fluorosilicate
Authors: Liu Rui Ran , Qiu Yun Ren
Published: March 2013

A novel technology of preparing cryolite free of wastewater containing ammonia was studied by using industrial grade sodium fluorosilicate from phosphate fertilizer production. Effects of reaction temperature and pH were studied for the decomposition of sodium fluorosilicate, and the suitable reaction conditions were decomposition temperature above 54 °C and pH 8.4. Effects of Na/Al (molar ratio of Na to Al in the raw materials), reaction temperature and pH on the quality of cryolite were investigated for the synthesis of cryolite. The results indicate that the obtained cryolite can meet the national first-grade quality standard of China at the conditions of pH from 3.0 to 5.0, Na/Al from 2.8 to 3.0 and temperature above 70 °C.
Dissolution Behavior of Cast WC Particles in NiCrBSi-WC Coatings by Laser Induction Hybrid Cladding
Authors: Zhou Sheng Feng , Dai Xiao Qin
Published: March 2013

In order to characterize the dissolution of cast WC particles in Ni-based WC coatings by laser induction hybrid rapid cladding, NiCrBSi+50 wt.% WC coatings are produced on A3 steel by low and high speed laser induction hybrid cladding (LIHC). When laser scanning speed is only 600 mm/min, the crack-free coating has pores and its dilution is as high as 45%. At the bottom of coating, the cast WC particles are dissolved completely and the herringbone M6C eutectics are precipitated. In the center of coating, the cast WC particles are also dissolved completely and the acicular, blocky and dendritic carbides with relatively low hardness are precipitated. At two sides of coating, some cast WC particles are dissolved partially and interact with Ni-based alloy to form an alloyed reaction layer, while others preserve the primary eutectic structure and high hardness. When laser scanning speed and powder feeding rate are increased to 1500 mm/min and 85.6 g/min, the coating has cracks but no pores. Its dilution can be markedly decreased to 7.8%. Moreover, a majority of WC particles are still composed of primary eutectic structure and keep their high hardness, which can play a positive role in strengthening Ni-based metallic matrix.
The Removal of In2O3SnO4 Thin Film Using an Arc-Form Tool for the Precision Recycling of Defective Digital-Paper
Authors: Pa P.S.
Published: March 2013

A newly designed arc-form shaped tool was used to carry out precise micro electrochemical etching (MECE) to remove Indium-tin-oxide (In2O3SnO2) thin-film nanostructures from the optical PET diaphragm surfaces for digital-paper surface. For this precise removal process, a higher current with a faster feed rate of the optical PET diaphragm effectively achieved rapid material removal. A pulsed direct current can improve dregs discharge and is advantageous when associated with fast PET feed rates, but this raises the total current required. A higher temperature or flow velocity of the electrolyte corresponds to a higher removal rate of the In2O3SnO2 nanostructures. A high rotational speed of the arc-form shaped tool corresponds to a higher removal rate of In2O3SnO2. A large cathode, along with a small gap-width between the cathode and the PET diaphragm, increases In2O3SnO2 removal rates. A thin cathode, or a short arc length of the arc-form anode, reduces the time taken for In2O3SnO2 removal.
Photocatalytic Activity of Ag2S/K2Ti4O9 for Rhodamine B Degradation under Visible Light Illumination
Authors: Cui Wen Quan , Lin Shuang Long , Ma Shan Shan , Liu Li , Liang Ying Hua
Published: March 2013

The composite Ag2S/K2Ti4O9 photocatalyst was synthesized via a precipitation method. The structure of the photocatalyst was determined by powder X-ray diffraction, scanning electron microscope. The photocatalytic properties for organic matter degradation of the photocatalyst were examined under visible light irradiation. The results showed that, the sample which synthesized at 25°C via a precipitation route，using nitric acid silver and thiourea as the raw materials in the absence of any surfactants or templates has the highest crystallinity and investigated its catalytic behavior. RhB as degradation object, different dosing quantity of the degradation rate were examined, The best dosing quantity (1000 MgL-1) degradation rate was 18.93%. And with K2Ti4O9 for ontology, the degradation of different load rate were examined, The best load (25%) of the degradation rate is 20.57%. The results revealed the Ag2S potential applications in photocatalytic degradation for organic pollutants.
Cell Structure Refining Mechanism of Pure Aluminum Foam with Fine Cell Structure
Authors: Luo Xiao Xu , Zuo Xiao Qing , Wang Yong Sheng
Published: March 2013

Cell structure refining mechanism of pure aluminum foam with fine cell structure has been studied. The results illustrate that the preparation of pure aluminum foam with fine cell structure is related to the following factors. Moderate melt viscosity is adopted to harmonize the relationship between the TiH2 dispersion and the bubble stabilization. When the stirring speed of stirring foaming process is 3000rpm, a more uniformed TiH2 dispersion in aluminum melt is expected, and bubbles are broken up to reduce the average cell diameter. Pre-oxidizing of foaming agent delays its starting decomposition time, hence to increase the dispersion uniform of foaming agent. Un-decomposed foaming agent or other solid particles, and initial bubbles in the aluminum melt can act as the nuclei of bubble heterogeneous nucleation. Increasing the uniformity of these initial bubbles and solid particles is helpful to fabricate pure aluminum foam with fine cell structure.
Thermal Storage and Release Properties of Aluminum Foam - Paraffin Composite Phase Change Materials
Authors: Luo Xiao Xu , Zuo Xiao Qing , Zhao Ming Wei
Published: March 2013

Aluminum foam-Paraffin Composite Phase Change Materials (APCPCMs) were fabricated by aluminum foam and paraffin, and the thermal storage and thermal release properties of the composites have been studied. The results are shown as follows. (1) When the volume ratio between APCPCM and water is 1:4, the time for the temperature changing of APCPCMs with aluminum foam porosity being 54.81%, 60.52%, 64.37% and 69.74%, from 24°C to 66°C, is 190s, 305s, 380s and 395s respectively. The thermal release time of these APCPCMs is 270s, 355s, 540s and 600s after being put into 24°C water, and resulting in a water temperature increase by 8.2°C, 8.7°C, 9.4°C and 10.1°Crespectively. (2) APCPCM with aluminum foam porosity 60.52% is compared with aluminum foam and paraffin, the thermal storage time of these three kinds of materials is 305s, 60s, 870s, and the thermal release time is 355s, 30s, 1470s respectively. (3) The equivalent thermal conductivity coefficient of the APCPCMs with aluminum foam porosity ranging form 69.74% to 54.81% is between 61.16 W•m-1•k-1 to 91.4W•m-1•k-1.
An Optimum Design of Piling Machine Column with FEM
Authors: Liu Wen Ping , Han Yu Ming , Jin Jie
Published: March 2013

As the construction technique of cement-soil composite piles is winning general popularity in building industry, the development of new types of piling machines has witnessed a growing trend in China in recent years. In the paper, a mechanical analysis for a piling machine column is conducted, based on the virtual prototype proposed in a previous portion of our research work in this area. To obtain the stress distribution at certain interesting locations of the column, working conditions are defined. In accordance with the simulation results, optimum design is carried out for the joint between the column and the tension diagonal, as well as that between the column and base frame. Finally, the strength adequacy of the vertical column is validated. With the optimum method, the design cycle of piling machine is greatly shortened and the analysis cost decreased.
Pavement Performance of Low Dosage Cement Stabilized Gravel Powder Mixed with Aggregates
Authors: Zhuang Chuan Yi , Ye Ya Li
Published: March 2013

On the basis of test analysis, mix design of cement stabilized gravel powder, cement stabilized gravel powder mixed with 20% aggregates and cement stabilized gravel powder mixed with 40% aggregates were compared, their unconfined compressive strength were tested, and the mixed aggregates ratio and mix design were ultimately determined. The experimental results show that mixing a certain amount of aggregate can reduce cement dose and meet the design strength. Engineering project cost by mixing with a certain amount of aggregate was little higher than that of cement stabilized gravel powder. Comprehensively considering technical and economic factors, the recommended amount of aggregates mixed with 30% and cement dose of 2%.
Analysis of Specific Load Capacity of Radial Hybrid Magnetic Bearing
Authors: Wang Chun E , Fang Jian Cheng
Published: March 2013

This paper proposes a method based on vector calculation of flux density to evaluate the specific load capacity (SLC) of radial hybrid magnetic bearing (RHMB). The vector sum of the flux densities generated by the permanent magnet and the control current is calculated in this method, and then the functional expression of the SLC is built up via the flux densities. The influence of outer rotor diameter, fraction of circumferential rotor surface covered by poles and the length of the air gap are analyzed. It turns out that the SLC decreases with the maximum force of the bearing, and increases first and then decreases with the increase of pole area and length of the air gap. The maximum attainable SLC for RHMB of all sizes does not vary substantially from 23:1. The results of the analysis provide basis for the prediction of volume and mass for the RHMB in application.
A Study of Strain Distribution and Cell Adhesion of MicroHA/CS Composite Scaffold under Mechanical Loading
Authors: Zhang Jian Ming , Li Rui Xin , Ren Ting Ting , Shi Cai Hong , Li Hao , Wan Zong Ming , Guo Yong , Wang He Yan , Zhang Xi Zheng
Published: March 2013

Mechanical stimulus is one of the factors that affect cell proliferation and differentiation in the process of bone tissue regeneration. It is difficult to directly measure stress and strain inside the scaffold, so we decide to use FEA (finite element analysis) to obtain the strain result. A uniform displacement equivalent to an uniaxial strain of 2500、3000、3500、4000、4500、5000με was applied to the solid material phase. These results suggested that apparent strain of 3000με was best suit to the physiology environment, which including more inner strain elements between 1000 and 3000με than others. When the strain more than 3000με, the number of nodes of more than 4000 μ ε increased obviously. This will cause damage to cells which adhesion in support of the pore wall. In vitro, MC3T3-E1 preosteoblast cells were used to investigate cell attachment, spreading and proliferation on the scaffolds via SEM (scanning electron microscopy). The results showed that cells could adhesion and proliferation well after 7 and 14 days under the dynamic loading of 3000με.
An Investigation of the Unstable Oscillation Phenomenas of Two-Phase Closed Thermosyphon
Authors: Tian F.Z. , Xin Gong Ming , Wang Xin Yu , Cheng Lin
Published: March 2013

Two-phase closed thermosyphon has been widely used in many heat transfer devices due to its high thermal conductivity, low cost and sample structure. During its starting and operation, there have some unstable oscillation, including dry oscillation, geyser boiling and carrying oscillation. An experimental investigation of unstable oscillation of two-phase closed thermosyphon was presented in the present paper. The experimental results showed that under the same starting power, geyser boiling is easy to achieve stability with the cooling power increasing, and under the same cooling power condition, geyser boiling could be significantly affected by the starting power. At the situation of high heating power, carrying oscillation happened easily, which caused great temperature fluctuation and disastrous effects on the heat pipe.
The Comparative Modal Analysis of Simulation and Experiment on the Electronic Button-Sewing Machine Shell
Authors: Zhang Li , Nie Guang Yuan , Wu Hong , Chen Jie
Published: March 2013

In this paper, the simulation with ANSYS software and the experimental modal analysis by impacting are carried out on the electronic button-sewing machine shell. The modal parameters, such as the natural frequency, the damping ratio and the mode shape, are obtained. Comparative analysis of their results shows that the mode shapes of the machine shell are mainly the outward-expanding and inward-contracting vibrations, which provides a useful reference for vibration and noise reduction of the electronic button-sewing machine.
Analysis on Crack Types and Causes of Junshan Bridge’s Steel Box Girder Orthotropic Plate
Authors: Cheng Jian Hua , Xiong Jian Min , Dai Jie
Published: March 2013

The fatigue cracking of orthotropic plate is a fatal problem for the long operation of steel bridge safely. There are numerous fatigue cracks appearing on Junshan Bridge, which locate mainly on diaphragm, U-Rib and fillet weld between the U-Rib and deck. Based on the location of fatigue cracks, the paper analyzed the causes of fatigue cracking from three aspects of mechanics cause, detail design and manufacturing factors, providing scientific basis of future health monitoring for bridges.
Electron Paramagnetic Resonance Study and Magnetic Property of Ni-Doped Titanate Nanorods
Authors: Wang Xin Wei , Shi Xue Ting , Lv Shu Peng , Chen Jun , Wang Suang Yin
Published: March 2013

Ni-doped titanate nanorods were synthesized from anatase TiO2 powder and Ni nitrate using a one-step hydrothermal reaction in alkaline solution. The nanorods are straight with lengths a few micrometer and diameters between 80 and 120 nm. The Ni-doped nanorods have the similar structure as hydrogen titanate nanorods of monoclinic structure. Magnetic measurement revealed that Ni-doped titanate nanorods are ferromagnetism at 300K. Electron paramagnetic resonance were studied and the spectra showed that a broad asymmetric signal and a signal in low field appeared due to the Ni ions incorporated into the titanate lattice. The results suggest that Ni-dopants play an important role in the ferromagnetism. The ferromagnetic response could be attributed to Ni intercalated into the titanate lattice.
Effect of Growth Atmosphere on the Structural, Optical and Magnetic Properties of Fe-Doped In2O3 Films
Authors: Xing Peng Fei , Sun Shao Hua , Wu Ping
Published: March 2013

Room temperature ferromagnetism was observed in Fe-doped In2O3 films deposited on fused quartz substrates by radiofrequency magnetron sputtering in N2 and O2 atmosphere, respectively. Results show that with increasing the O2 and N2 flux, the lattice constant increases, the optical band gap decreases, and the ferromagnetism weakens. Moreover, the decrease in the saturation magnetization for films deposited in N2 atmosphere is more apparent than that deposited in O2 atmosphere. We think the reason is that in our Fe-doped In2O3 films the ferromagnetism is mainly mediated by the oxygen vacancies, and as an acceptor defect, N ions can decrease the concentration of the oxygen vacancies to a greater extent than the O ions.
Single Wafer Atomic Layer Deposition Reactor Design
Authors: Zhou Tao , Jiang Hua Wei , Xiao Yue , Yao Ying Bang , Shan Bin , Chen Rong
Published: March 2013

Atomic layer deposition (ALD) is a very attractive ultra-thin film deposition technique. With the feature size of IC industry continues going down, ALD has received more and more attentions for its accurate sub-nanometer thickness control as well as superior uniformity and conformality. The further development of ALD technology emphasizes on both process and equipment innovations. A single-wafer bottom-heated reactor is constructed successfully, and the Al2O3 is deposited with ~2% uniformity across a 4-inch wafer. Furthermore, the gas delivery system and heating devices are studied by the combination of ANSYS simulation and experiments. These parameters that influence the uniformity and conformality of deposited films have been further optimized to obtain better performance. As a result, a new reactor with showerhead gas delivery and radiation heating system is designed.
Sol-Gel Derived TiO2 Coating on Hydrothermally Roughened NiTi Alloy
Authors: Dong Bing Hui , Zhang Chen , Alajmi Zafer , Wang Ke Yong , Fu Tao
Published: March 2013

Nearly equiatomic NiTi alloy is hydrothermally treated in a urea solution at 150°C to form nanostructures at the surface, with the aim to improve the structural quality of sol-gel deposited TiO2 film. Nanosheets film of ammonium titanate is formed on NiTi alloy after 8 h hydrothermal treatment, and the sol-gel TiO2 film on it is smooth and crack-free. Anatase TiO2 films consisting of nanoparticles and granular deposits are formed on the NiTi samples hydrothermally treated for 16 h and 24 h. The subsequently deposited TiO2 films have short cracks, because the nanostructured films can not completely balance volume shrinkage of the gel film during the drying and heat treatment processes. Water contact angles of the duplex treated NiTi samples increase during ageing in air, but are all reduced to below 10 after 2 h UV irradiation treatment. Potentiodynamic polarization tests in 0.9% NaCl solution indicate that the duplex treated NiTi samples have much better corrosion resistance than the polished one.
Study on the Application of FBG Technology in Rainfall Monitoring
Authors: Tan Dong Jie , Han Bing , Li Liang Liang , Liu Jian Ping
Published: March 2013

In order to overcome the disadvantage of low accuracy for traditional rainfall monitoring technologies, and solve the problems in real-time data acquisition, automatic processing and remote transmission for the existing meteorological observation, we design a new rainfall monitoring device based on fiber grating technology, which has such advantages as real-time capability, high sensitivity, high accuracy, unattended operation and can fairly meets the present requirements of meteorological observation.
The Synthesis of Lithium Aluminate Materials and its Performance of CO2 Absorption
Authors: Wang Yin Jie , Liu Ji Ping , Kan Mei Xiu , Liu Ze Quan
Published: March 2013

Use Nanoscale α-Al2O3 as raw materials, prepared by high temperature solid state reaction, we produced the Lithium Aluminate (Li5AlO4) which can directly absorb CO2 at a temperature between 450°C and 650°C. Respectively use the method of scanning electron microscopy (SEM)、X-ray powder diffractometer (XRD) and thermogravimetric analyzer (TG) for the morphology、structure and the performance of CO2 absorption analysises. The results show that the synthesized Lithium Aluminate (Li5AlO4) materials have a performance of CO2 absorption.
The Preparation of the Highly Preferred Orientation of AlN Thin Films on ZnO Substrates
Authors: Ding Nan , Xu Li Ming , Wu Bao Jia , Gu Guang Rui
Published: March 2013

Zinc oxide (ZnO) films were prepared on Si substrates and then aluminum nitride (AlN) films were deposited on ZnO films by radio frequency (RF) magnetron sputtering. The crystal orientation, crystallite structure and surface morphology of AlN/ZnO films were characterized by X-ray diffraction (XRD), Raman spectrum and scanning electron microscopy (SEM). It was indicated that the AlN films were closely deposited on the ZnO film and had good crystallinity. Moreover, about 1μm-sized crystal particles with high c-axial orientation distributed uniformly on the AlN/ZnO film surface. It was indicated that ZnO could be a promising candidate as buffer layer for preparation of AlN thin films.
Fabrication of PAN Hollow Fiber Ultrafiltration Membrane with Salt Porogen
Authors: Tan Jin Shan , Liu Xiao Mian , Yu Bing , Cong Hai Lin , Li Ze Jing , Zhao Yun Chao , Lian Yi Chen , Guo Xin Yu
Published: March 2013

Polyacrylonitrile (PAN) hollow fiber ultrafiltration membranes were prepared by wet spinning method using lithium chloride (LiCl) or calcium chloride (CaCl2) as porogen and dimethyl formamide (DMF) as solvent. The effects of PAN/LiCl and PAN/CaCl2 ratios in the spinning solution on the permeation properties of the formed membranes were studied.
Synergistic Effect of Nano Fe2O3 on Intumescent Flame Retardant Polypropylene Systems
Authors: Zhao Wei , Liu Ji Ping
Published: March 2013

Nano Fe2O3 were added into polypropylene (PP) / ammonium polyphosphate (APP) / melamine phosphate (MPOP) / 1-oxo-4-hydroxymethyl-2,6,7-trioxal-phosphabicyclo-[2.2.2]octane (PEPA) to prepare intumescent flame-retarded nanocomposites. The flame retardance and thermal stabilization and intumescent char layer have been investigated by UL-94 test, TGA and SEM. Result showed that the behavior of this intumescent system can be enhanced significantly by the addition of small amounts of nano Fe2O3. TGA results present higher thermal stability of the PP-IFR-Fe2O3 in high temperature when compared with the PP-IFR. SEM indicated the char layer from the PP-IFR-Fe2O3 system has a compact and tough char structure compared with the PP-IFR. Adding 0.3 wt% and 27 wt% IFR into PP, the PP-IFR-Fe2O3 system provided good fire retardant behavior, mechanical properties and achieved UL94 V-0 rating.
Preparation of Polyaniline-Modified TiO2 Nanoparticles by In Situ Chemical Oxidative Polymerization and their Photocatalytic Activity for the Degradation of Methyl Orange under Natural Light
Authors: He Zhao Pin , Shi Yuan Chang , Sun Li Bo , Li Bo , Nie Hong Jiao
Published: March 2013

Polyaniline-modified nanocrystalline TiO2 composites were successfully prepared by in situ chemical oxidative polymerization and used as an efficient photocatalyst for the degradation of methyl orange under natural light. The nanocomposites were characterized by Transmission electron microscope (TEM), Scanning electron microscope (SEM), Fourier transform infrared spectra (FT-IR), X-ray diffraction and UV-Vis spectra. Results show that polyaniline-modified nanocrystalline TiO2 composites exhibit significantly higher photocatalytic activity than that of neat TiO2 on degradation of methyl orange under natural light. In addition, the conductivity of polyaniline-modified TiO2 nanoparticles was also investigated and has reached 2.65 × 10-1 S cm-1 at room temperature.
Mechanism of Mechanical Energy Aided Aluminizing
Authors: Wang Xiu Chun , Wei Jun , Zhang Jing , Ma Jie , Liu Shuo , Yi Xi Bin
Published: March 2013

In this paper, the effects of aluminizing agent composition, filler particle size, process parameters and adding impinging particle into aluminizing agent on the thickness of aluminizing layer were investigated. The mechanism of the significant reduction in aluminizing temperature using aluminizing agent was analyzed. The results indicate that the aluminizing temperature can be reduced to 500°C through mechanical energy aided aluminizing. The mechanical energy aids to improve the surface adhesion probability of Al powders on the specimen surface, increases the chemical activity and adhesion strength of Al powders, thus the aluminizing temperature is greatly reduced.
A DFT Study of the Effect of Natural Impurities on the Electronic Structure of Sphalerite
Authors: Jiang Deng Bang , Deng Wen , Lan Yao Zhong
Published: March 2013

The electronic and reaction properties of natural sphalerite containing seven typical kinds of impurities is studied by the density-functional theory (DFT). Mn and Ga impurities result in the Mulliken charge of the Zn atom reduced and consequently might decrease the ionicity of sphalerite; while Fe, Cd, In, Ge and Tl impurities lead to the increase in the Mulliken charge of the Zn atom. The frontier orbital calculations show that Mn impurities might lead to the over-oxidization of sphalerite, which may cause the further oxidation of lead xanthate, and thus are unfavorable for the flotation of sphalerite.
The Application Research on Electrical Deposition Method for Preparing Pt-Ni Alloy Nanotubes and its Modified Sensor in the Detection of Dopamine
Authors: Chang Yan Bing , Yang Xiao Li , Liu Yan Ling , Feng Ya Juan , He Qiong
Published: March 2013

This paper states how to prepare Pt-Ni alloy nanotubes in PC spray gold template using electrical deposition method, modify it to the glassy carbon electrode and make into dopamine sensor. It compares that cyclic voltammetry behavior of the bare glassy carbon electrode and Pt-Ni alloy nanotubes modified glassy carbon electrode. The conditions that glassy carbon electrode is modified by Pt-Ni alloy nanotubes for determination of dopamine were optimized. Under the optimized conditions, the test linear is in the range of 1.0×10-6 ~ 1.0 × 10-3 mol/L, detection limit is 4.0×10-7 mol/L, the recovery rate is 95.2%. This method has the advantages of simple operation, little amount of sample, high sensitivity and good reproducibility.
Preparation and Property of a Superhydrophobic Glass Sealant
Authors: Jiao Ming Ming , Yu Bing , Cong Hai Lin , Yang Shu Jing , Huang Shi Ming , Wang Shao Peng
Published: March 2013

The recipe of silicone glass sealant was studied, and the influence of crosslinking agent, plasticiser and reinforcing agent on its property was investigated. After compositing the glass sealant with polytetrafluoroethylene (PTFE) nanoparticles, a novel superhydrophobic silicone/PTFE glass sealant was obtained with contact angle of water more than 150o, and the effect of PTFE nanoparticles on superhydrophobicity of the nanocomposites was researched.
Ammonia Gas Sensor Based on Aniline Reduced Graphene Oxide
Authors: Huang Xiao Lu , Hu Nan Tao , Wang Yan Yan , Zhang Ya Fei
Published: March 2013

Here we demonstrate a promising gas sensor based on aniline reduced graphene oxide (RGO), which is fabricated through drop drying RGO nanosheets suspension between the electrode arrays to create conductive networks. RGO, as the sensing materials, which is prepared via the chemical reduction of graphene oxide (GO) by aniline, has been characterized by infrared spectroscopy, UV-Vis spectroscopy, transmittance electron microscopy and scanning electron microscopy. The sensing properties of RGO have also been studied, and the results show that RGO reduced from aniline (RGO-A) exhibits an excellent response to ammonia gas (NH3). Comparing with the RGO reduced from hydrazine (RGO-H) and polyaniline (PANI) nanofiber, the RGO-A exhibits a much better response to NH3 gas. The response of the sensor based on RGO-A to 50 ppm NH3 gas exhibits about 9.2 times and 3.5 times higher than those of the device based RGO-H and PANI nanofiber respectively. In addition, the RGO-A sensor exhibits an excellent repeatability and selectivity to NH3 gas. The oxidized aniline, i.e., polyaniline, which is attached on the surface of RGO sheets through π–π interaction, plays important roles in the final sensing performance of the device, and benefits for the application of the sensor in the field of NH3 gas detection.
Tool Life Evaluation Methods of Heavy Forging Hogging Machining Based on Image Processing Technology
Authors: Liu Xian Li , He Geng Huang , Li Wen Dong , Yan Fu Gang
Published: March 2013

In practical production, the evaluation method of tool life that heavy forging shell ring is in hogging machining compare the length of its processing surface in a single direction, the method considers neither the actual cutting distance of cutting tool, nor the impact times sustained by the cutting tool, this paper provides a new method of tool life evaluation based on image processing technology. Through collecting images of processing surface of the work-piece, which contains the different colors and brightness caused by processed and unprocessed, and image processing, analysis and calculation, the new method can accomplish the calculation about the effective cutting distance of cutting tool and the number of impact force about cutting tool, it will be more scientific and more reasonable evaluation method of tool life. Finally, one example is given. New method can be used to provide accurate evaluation of tool life and material machinability for the machining of large forgings.
Design on Tracing of Automatic Handling Robot Car with Six Degrees of Freedom
Authors: Wang X.J. , Fu X.G.
Published: March 2013

The micro controller used in car tracing module is also a single-chip microcomputer which is mainly used for collecting 3 sensor values, transmitting it to the master control single-chip microcomputer for processing which then produce corresponding strategy and makes the corresponding control to change the omni-directional wheel. In the meantime, the micro controller used in car tracing module even for carry out the sending and receiving of communication module data, ensure car moving according to the set orbits.
Design and Application of Rapid Manufacturing Domain Ontology to Support Resource Sharing
Authors: Wu D. , Hu Q.X. , Yao Y.
Published: March 2013

Facing the abundant service resources, how to make the heterogeneous distributed resources information system has the meaning that can be understand between man-machine and machines, search conveniently and implement the resources integration, achieve information access and query better as well as the interoperability between systems, it is a challenge it faces which implementing the resources sharing and intelligence services, but also a problem which to improve the service informatization level for RM industries to be solved. To facility services resource sharing in Rapid Manufacturing (RM) industry, mainly discussed demand analysis and establishment principle of RM domain ontology. Based on the many years of experience and enterprise instances, domain ontology was described conceptual and expressed knowledgeable and model structure was established. The knowledge representation method is adopted based on the domain ontology query model and partial examples of service description are given. In order to solve semantic fuzziness and realize integration, interoperability and reusability of enterprise service by building domain ontology which can satisfy shared understanding of interested parties. On this basis, integrated service system architecture was designed to support resource sharing. The methods had been applied preliminarily and would provide the basis for the future work and extended field.
Research on Application of Deep Foundation Pit Decompression Dewatering Technology and Impact on Surrounding Environment
Authors: Zhang Dong Dong , Ding Jun Wen , Wang Rong Biao
Published: March 2013

The studies application of deep foundation pit decompression technology focusing on special engineering geological and hydrogeological conditions. Taking foundation pit dewatering of certain rail transit station as an example, designs deep foundation pit decompression precipitation technology scheme with hydrogeological parameters obtained through pumping test, and assesses and monitors its impacts on surrounding environment according to measured data on project site, which has achieved good results in practical engineering application and provides foundation for construction of rail transit lines.
Study on Finite Element Modeling of Girder Bridges
Authors: Xia Xiao Hui
Published: March 2013

The modeling techniques selected for girder bridges should be capable of including physical behavior, such as composite action and the eccentricity effect between the slab deck and the girder. In this paper, we find that the ANSYS has the capability of offsetting the beam element from a reference node location in order to define the centric location of the section relative to the node location.
Analytical and Numerical Anti-Floating Study Concerning the Shield Tunnel across the River
Authors: Zhang Shao Qin , Yuan Wen Jun , Zhang Hui Hua , Huang Ling , Zhong Yan Fen
Published: March 2013

In the present paper, we consider the floating problem of river-crossing shield tunnel in the process of construction. Firstly, based on the theoretical analysis of equilibrium states of excavation face and shield segments away from shield tail, we obtain the equation for calculating the minimum thickness of overlying soil in the associated equilibrium states. Secondly, the above derived formula are applied in the Fuhe bridge project, which is a sub-project of No.1 Nanchang metro; at the same time, numerical simulation is carried out to further evaluate the safety with the change of overlying soil thickness. Lastly, some useful conclusions are drawn through comparative study, which is helpful to similar projects.
Monitoring Study on Drift Deformation by Shield Tunnel
Authors: Sun Hai Xia , Zhao Wen
Published: March 2013

Take the one-third of the allowable values as the basic value. The control standards of the ground subsidence is 30mm, and the control standards of the ground swell is 10mm. Take one typically stretch of sites as research object by the buried depth and plane disposition condition. Take ten sections and the kilometer post. Consider 52 contents as of an analysis. The maximum subsidence is mostly kept within 13mm. The monitoring data of each lateral section are certain differences because of the different gemological conditions, the water quality, soils covered and so on. When the shield drives off the monitoring section, the subsidence is about 6mm~16mm and 50% of the total subsidence. The main subsidence appears after the shield tail pass out for sand.