bluuebunny/crossref_metadata_2025 huggingface dataset:
Improved Method of Medical Image Reconstruction Based on MC Algorithm
Authors: Huang Xue Mei , Liu Wei Hong , Wang Hong Quan
Published: October 2011

Some improvements were put forward to modify the medical image reconstruction method based on MC algorithm. Computing redundancy, bad expansibility and “scalelike effect” lie in standard MC algorithm now. To solve the repeating calculation redundant problem, a suitable data structure was applied to seek cubes; by making segmentation result as the input of MC algorithm, the author eliminated the limitation of expansibility; by smoothing the normal vector of isosurfaces, this paper improved the image displaying effect. Finally, a special storage data structure was designed to save the non-manifold triangle model obtained from MC algorithm. The modification mentioned above has been realized in 3D reconstructing software-MedLG which was developed by authors’ institute and applied successfully in customized prostheses designing already. Moreover, The reconstructed model can also be used in biomechanics researching.
Modeling and Analysis of Opportunistic Spectrum Sharing Systems with Markov Approach
Authors: Zhang Chen Yu , Liu Kai
Published: October 2011

Opportunistic spectrum sharing has become a promising approach to fully utilize the scarce spectrum resources. In this paper, we analyze the performance of a wireless system consisting of two secondary user (SU) groups with different priorities, which are defined to satisfy the different quality-of-service (QoS) requirements. At the same time, we take the errors of spectrum sensing (i.e. miss-detection and false alarm) into consideration. We derive system performance metrics such as SU forced termination probability and blocking probability. Our results suggest the proposed model can improve the secondary system capacity significantly even under unreliable spectrum detection.
Structure Health Monitoring Using Support Vector Data Description and Wavelet Packet Energy Distributions
Authors: Duan Chen Dong , Liu Yi Yan , Gao Qiang
Published: October 2011

A new monitoring and diagnostics method using support vector data description (SVDD) is proposed which only needs samples under healthy condition. The method is an ideal candidate for coping with the problem of a shortage of the unhealthy condition samples. We firstly select several nodes of the monitored structure, and decompose the signals from these nodes with wavelet packet transform (WPT). To monitoring structural health efficiently, we assemble a combine feature by using wavelet packet energy distributions of these nodes. The feature is then applied as the input of a developed SVDD classifier. Experiment shows that the SVDD classifier was able to distinguish the normal and abnormal condition ideally, and can be used as an automation approach for structural health monitoring.
Study on Numerical Simulation Analysis of Creep Model for Tianjin Tower
Authors: Duan Xiang Yang , Li Zhi Wei , Yang Yang , Gong Yu Jie
Published: October 2011

Tianjin tower is the landmark building of Tianjin, and is of out-of-codes super high-rise concrete filled steel tube (CFST)-steel reinforced concrete (SRC) hybrid structure. As to this type of architecture, the impact of creep on the concrete work construction cannot be ignored. Considering the complexity of creep calculation of the integral structure, the simplified creep calculation model will be adopted for the construction simulation in this paper. The comparison with the results of on-site construction monitor shows that the simplified model is reasonable and practical. Additionally the analysis on the impact of creep on CFST structure is made, providing theoretical and practical references for performance evaluation of the structure of Tianjin Tower and the selection and optimization of construction methods of Tianjin Tower.
Calculation on Dynamic Angle of Repose for Submarine Pipeline on Sandy Seabed
Authors: Yang Li Peng , Shi Bing , Guo Ya Kun
Published: October 2011

This paper investigates the dynamic angle of repose underneath the submarine pipeline. Using a sand deposition model, the analysis of forces acting on non-cohesive sand particle gives the formulas of dynamic angle of repose in the scour hole. The formulas for different scenarios are discussed and it is observed that the angle upstream the vertical axis of the pipe increases with the increase of sand Reynolds number. The angle downstream, however, shows a contrary trend. Besides, the angle upstream is bigger than that downstream. The comparison of the calculation results with the experimental data indicates that the formula predicts the angle of scour hole under a pipeline reasonably well.
Research on Hydraulic Characteristics of Cutthroat Flume in Irrigation District
Authors: Qi Qing Lan , Kong Qiang , Ye Qing Qing
Published: October 2011

In the background of the cutthroat flume of the second stem II station in the Ye River hub of Shijiazhuang, the model test is selected to analyse the hydraulic characteristics of the cutthroat flume. The results show that: (1) The influencing factors on the discharge coefficient in the calculating formula for flow deduced by theory are drawn, the discharge coefficient of the free outflow is relevant to the head above weir and the height of weir, and that of the submerged outflow has relevance to the height of weir and the upstream and downstream water level; (2) the critical condition for the submergence of cutthroat flume is determined, when the ratio of the water depth in the downstream and upstream is less than 0.76, the flow is free outflow, otherwise it is submerged outflow; (3) Based on the regression analysis, the empirical formula of discharge coefficient for the free outflow and submerged outflow are obtained, and the precision is proved to be reasonable by the error analysis.
Analysis of Air Flow and Turbulent Fluxes Features of Night Fog
Authors: Wu Bin Gui , Wang Zhao Yu , Xie Yi Yang
Published: October 2011

The air flow and turbulent fluxes features during the radiation fog formed on the dawn of 17 October 2007 is discussed in order to study the mechanism of an unexpected night fog, based on the meteorological and turbulent data obtained from the 250 m height tower in Tianjin, as well as the NCEP reanalysis data and other observational data. The results show that the lower layer easterly flow coming from the south region of the Northeast cold high pressure led to remarkable temperature fall and humidity value increase in the daytime prior to the fog formation, which quickly turned the dry boundary layer to be moist. The vapor transfer indicated that the vapor of the radiation fog was provided by the easterly advection from Bohai Sea, not from local area. Turbulent vapor fluxes increased ten times as that before the fog. The horizontal vapor fluxes transported against the wind direction, which led to the escape of water vapor from Tianjin city and the dissipation of fog.
Remediating Lead, Zinc, Cadmium and Arsenic Contaminated Steel Smelting Site with Hydrochloric Acid and Sodium Hydroxide
Authors: Li Yan Mei , Lei Mei , Chen Tong Bin
Published: October 2011

A-two step soil washing experiment was conducted to search an effective washing technique for the remediation of the contaminated soil from a steel smelting site. Our results indicated that 0.5M of hydrochloric acid alone could reduce soil cadmium concentration to lower than 1 mg kg-1, 1M of hydrochloric acid alone could reduce soil lead concentration to lower than 140 mg kg-1, 2M of hydrochloric acid combined with 0.2M of sodium hydroxide could reduce soil zinc concentration to lower than 200 mg kg-1 and reduce soil arsenic concentration to lower than 20 mg kg-1, the washed soil could be safely reused according to the national exhibition land quality standards of grade A.
Spatial-Temporal Pattern of Tourism Economic Differences in Gansu Province
Authors: Shi Pei Ji , Wang Zu Jing , Li Wei
Published: October 2011

This paper selects 9 indicators to build the economic development indicators of urban tourism in Gansu Province. We use the principal components analysis method to analyze the level of tourism economy development, with the help of ArcGIS and GeoDA software. And it reveals the regional tourism economic differences between 14 prefecture-level cities in Gansu Province. The result indicates that the level of tourism economic development shows features of general section in the geographical space, and it formed a "dumbbell" type space pattern. Then we analyze the main causes of this phenomenon, and find out solutions to solve the problem.
Study on the Purification Effects of Constructed Wetland Plants in TP Disposal in Living Wastewater
Authors: Lu Min , Pei Fei Fei , Song Xiu Kui , Guo Zhen
Published: October 2011

The study on the species selection of constructed wetland plants and the purification effects of the constructed wetland plants is the key to ecological wastewater treatment technology. The purification effects of different residence time of wastewater, different constructed wetland plants and their synergistic effect are studied in TP disposal in living wastewater. The results show that the best plant combination in purifying TP is that of Arundo donax, Typha orientalis and Canna generalis, followed by that of Phragmites communis, Arundo donax and Canna generalis. The best plant species in purifying TP is Canna generalis, followed by Arundo donax.
Experimental and Numerical Study of Transient Distortion in Titanium Alloy Tig Welding
Authors: Wang Rui , Li Dong Feng , Han Xin Li , Zhang Jianxun
Published: October 2011

In this paper, the convex distortion and transient distortion characteristics of TIG welding for a titanium alloy with finite dimensional thin plate were investigated experimentally and numerically. A three dimensional thermal-mechanical finite element method (FEM) was adopted to predict the characteristics of Transient distortion by taking the initial shape, gravity loading and restriction conditions into account. The simulation results were validated by the experimental results. The results show that the numerical simulations could provide accurate prediction on the Transient temperature and distortion processing. The temperature gradient through thickness, the dimension of plate and the clamping were main factors governing the distortion during welding.
Study on Optimization of Regional Spatial Structure Based on Land Use and Transport Accessibility: A Case Study of Pearl River Delta Region
Authors: Lu Xu , Liu Qing
Published: October 2011

This study presented a case study of Pearl River Delta(PRD) region. Using basic data of land use and transport network, the extraction of land use information and the analysis of transport network accessibility were performed to comprehensively analyze the land use and transport accessibility of PRD region. Moreover, suggestions on the optimization of regional spatial structure were also made. By this empirical process, the combination of accessibility with land use factors in regional spatial planning was investigated.
Application of Laboratory Tests Results of Dowel Joints in Cement-Splinter Boards VELOX into the Fully Probabilistic Methods (SBRA Method)
Authors: Lokaj Antonín , Vavrusova Kristyna , Rykalová Eva
Published: October 2011

The aim of this paper is determination of selected strength characteristics of dowel joints in cement-splinter boards VELOX on the basis of destructive testing and application of these results into the fully probabilistic SBRA method (Simulation Based Reliability Assessment).
Titanium Dioxide Thin Films: Effect of Annealed in Oxygen Ambient
Authors: Asiah Mohd Nor , Achoi M.F. , Abdullah Saifollah , Rusop Mohamad
Published: October 2011

Titanium dioxide (TiO2) thin films deposited on quartz substrate by spin-coating method using titanium (IV) butoxide has been studied. The aim of this paper is to investigate the effect of annealing in oxygen ambient on the morphology and optical properties of thin films. The distinct variations in the morphology of the thin films were observed from atomic force microscope (AFM) images. The transmission spectra obtained from UV-VIS-NIR showed the TiO2 thin films exhibited average transmittance value up to 80% in the visible region. Raman spectra of thin films annealed in O2 shifted from 142 cm-1 to 179 cm-1.
Fabrication of Nanopit Array Using Electron Beam Lithography
Authors: Maryam Alsadat Rad , Ibrahim Kamarulazizi
Published: October 2011

This work reported the fabrication of nanopits array pattern using electron beam lithography (EBL). The effects of electron dosage on pattern shape were evaluated through EBL with a positive resist, Poly Methyl Meth Acrylate (PMMA), under acceleration voltages of 20 and 30 kV. Pattern of nanopits with 200 nm diameter have been created on PMMA to investigate the effect of various electron beam doses. The SEM images have shown effect of the voltage and dosage variation on them. In addition, Monte Carlo simulation has been done to show the scattering of electrons and proximity effect at different voltages in PMMA in order to explain the experimental results.
Raman Spectroscopy and Field Emission Scanning Electron Microscopic Studies on Carbon Nanomaterials
Authors: Nor Aziah Buang , Fatiha Ismail , Othman Muhammad Zamir
Published: October 2011

Raman analysis is one of the main methods use to investigate type of graphitized carbon nanomaterials. It provides information on the vibration of crystal lattice, electron structure and regularity of crystal structure of the graphitized carbon materials. In this work the single step chemical vapour deposition (CVD) method was introduced for the direct growth of all as-synthesized carbon nanomaterials; carbon nanotubes (CNTs), carbon nanofiber (CNF), carbon nanosphere chain (CNSC) and CNT heterojunctions (HJCNTs). Series of metal catalysts were formulated from Ni, Fe, Cr and Cu, and were used in the synthesis of the respected carbon nanomaterials (CNMs). By introducing the right combination of the reaction conditions consisting of the formulated catalyst, reaction temperature and flow rate as well as type of carbon source resulted in the formation of different types of carbon nanomaterials. Raman spectra analysis revealed that the used of acetylene and ethanol as the carbon precursors are proficient to produce different form of carbon nanomaterials as depicted by the evolution of the G-band and D-band intensities. The FESEM micrographs obtained confirmed the morphology and types of the respected carbon nanomaterials synthesized in this study.
Dressing of Mwcnts with TiO2 Nanoparticles Using Modified Microwave Method
Authors: Haji Jumali Mohammad Hafizuddin , Firas K. Mohamad Al Asfoor , Radiman Shahidan , Umar Akrajas Ali
Published: October 2011

Optical properties of TiO2 dressed on the surface of MWCNTs have been investigated. The samples were prepared using modified microwave method and characterized using TEM, XRD and UV-Vis spectroscopy. A clear interface between MWCNT and TiO2 indicated strong attachment between these two nanostructures. Significant change in absorption spectra proved the absorption wavelength and band gap energy of TiO2 nanostructures can be controlled via dressing of MWCNT.
The Effect of Catalyst on Carbon Nanotubes (CNTs) Synthesized by Catalytic Chemical Vapor Deposition (CVD) Technique
Authors: Lim S.Y. , Norani M.M.
Published: October 2011

Catalyst plays a crucial role in determining the characteristics of carbon nanotubes (CNTs) produced by using thermal catalytic chemical vapor deposition (CVD). It is essential to investigate how the catalyst preparation affects the characteristics of CNTs because certain application demands specific size for optimum performance. This study reports the effect of the types of catalyst and the duration of the catalyst pre-treatment (wet etching time, dry etching time and ball milling) on the diameter of CNTs. The synthesized CNTs samples were characterized by scanning and transmission electron microscopy and Raman spectroscopy. Wet etching (2M hydrofluoric acid) time was varied from 1 to 2.5 hrs and the diameter range was found to be in the range of 23 to 52 nm. The diameter range for CNTs produced for 3 hrs and 5 hrs of dry etching treatment (with ammonia gas) are 38 to 51 nm and 23 to 48 nm, respectively. The diameter size of CNTs produced using Ni (14 to 25 nm) was found to be smaller than Fe (38 to 51 nm). There is a significant decrease in the diameter of CNTs by prolonging the wet etching period. Shorter and curly shaped CNTs can also be obtained by using Ni as the catalyst. Keywords: chemical vapor deposition, carbon nanotubes, catalyst pretreatment
Preparation and Characterizations of In0.1SnxZn0.85-2xS Powder Photocatalysts for Hydrogen Production under Visible Light Irradiation
Authors: Melody Kimi , Leny Yuliati , Shamsuddin Mustaffa
Published: October 2011

A series of In0.1SnxZn0.85-2xS solid solutions was synthesized by hydrothermal method and employed as photocatalyst for photocatalytic hydrogen evolution under visible light irradiation. The structures, optical properties and morphologies of the solid solutions were studied by X-ray diffraction, diffuse reflectance UV–visible spectroscopy and field emission scanning electron microscopy. From the characterizations, it was confirmed that In0.1SnxZn0.85-2xS solid solution can be obtained and they have nanosized particles. The highest photocatalytic activity was observed on In0.1Sn0.03Zn0.79S photocatalyst, with average rate of hydrogen production 3.05 mmol/h, which was 1.2 times higher than the In0.1Zn0.85S photocatalyst.
Nanostructured of Vanadium Phosphorus Oxide (Vpo) Catalyst Prepared by Sonochemical Treatment
Authors: Yee Ching Wong , Taufiq-Yap Yun Hin
Published: October 2011

A series of six nanostructures vanadium phosphorus oxide catalysts were synthesized through the starting material vanadium pentoxide which subjected to high intensity ultrasound irradiation with different duration of time. XRD patterns of all nanostructure vanadium phosphorus oxide catalyst were indexed to (VO)2P2O7 with one additional small peak which corresponds to the present of small amount of V5+ phase except for the catalyst that undergo 120 min of ultrasound irradiation time. The surface morphologies of the catalysts are uniform, well defined shapes and surface structures in nanoscale range but tend to agglomerate with each other to form larger particles. Furthermore, high amount of active oxygen species were released from V4+ phase (O--V4+ pair) for the nanostructures VPO catalyst which were synthesized with 30 min of ultrasound irradiation time and drastic increment in n-butane conversion (9 %) in catalytic evaluation test, suggested that these nanostructure VPO is an active catalyst for partial oxidation of n-butane towards malefic anhydride.
Butane Sensing Property of Si-ZnO Nanowires p-n Junction
Authors: Tiong T.Y. , Dee Chang Fu , Salleh M.M. , Yeop Majlis B. , Yahaya M.
Published: October 2011

The p-n junction has been formed by using p-type boron doped silicon and n-type ZnO nanowires (NWs). It was prepared by using simple vapour-transport deposition method. Gas sensing property has been examined by measuring the resistance change of the junction sample towards 1 % of butane gas at room temperature. Significant improvement of sensing behaviour was observed from the fabricated junction sample when it was compared to sample of non-p-n junction ZnO NWs. The increase in the sensitivity of the p-n junction ZnO NWs and the ability to regain the sensing power by returning back to the initial state at room temperature are useful for future sensing device with minimum power consumption. Keywords: ZnO nanowires, Si-ZnO nanowires p-n junction, room temperature sensing and butane gas
Fabrication of Photoelectrochemical Cell Using Highly Compact Vertical Array ZnO Nanorod
Authors: Taslim Rika , Rahman Mohd Yusri Abd , Umar Akrajas Ali , Salleh Muhamad Mat
Published: October 2011

Highly compact vertical array ZnO nanorods on the FTO coated glass was fabricated for photoelectrochemical cell of FTO/ZnO/electrolyte/platinum. ZnO nanorods were grown on the FTO substrate at room temperature via ammonia assisted rapid hydrolysis process technique. In typical process, ZnO nanorods were characterized by FESEM with vertical array oriented with average diameter and length of 48 nm and 218 nm, respectively. The sample was grown throughout the surface by using four cycle growth process. The photoelectrochemical cell property was studied in dark and under illumination of 100 mWcm-2 light. The cell exhibits photovoltaic effect with JSC of 0.22mAcm-2, VOC of 0.44 V, and conversion efficiency of 0.03%. Keywords: Vertical array ZnO nanorods, Photoelectrochemical solar cell
Iron Oxide Nanoparticles Conjugated Monoclonal Antibody for Immunochromatographic Strip Test
Authors: Noorhashimah Mohamad Nor , Nor Dyana Zakaria , Abdul Aziz Azlan , Noordin Rahmah , Khairunisak Abdul Razak
Published: October 2011

In this study, the synthesis of iron oxide nanoparticles (IONPs) and immunochromatographic (ICG) strip test of iron oxide conjugated with monoclonal antibody (IONPs-Ab) have been developed. The IONPs were synthesised using precipitation method and dispersed in water by applying polyethylene glycol coating. Several parameters that affected conjugations of the IONPs-Ab were studied namely iron oxide concentration, antibody volume, stabilizer concentration and the amount of SiPEG coating. From the transmission electron microscopy (TEM) image, the size of IONPs obtained was ~14 nm. Conjugate was tested with the ICG strip test lined with the antigen. The results showed 1.0μl SiPEG coating, 1 M IONPs concentration, 20μl of 1mg/ml antibody volume and 1% bovine serum albumin (BSA) were the optimum. Moreover, the IONPs-Ab was also tested with the Brugian filariasis positive and negative serum samples. The results showed positive result for the patient serum and negative result for the non-patient serum in just 15 minutes.
Growth Mechanism of Au-Catalyzed Zno Nanowires: VLS or VS-VLS?
Authors: Pung Swee Yong , Tee Chee Chee , Choy Kwang Leong , Hou Xiang Hui
Published: October 2011

A systematic study was carried out to study the effect of process parameters on the growth of Au-catalyzed ZnO nanowires (NWs). Growth of Au-catalyzed ZnO NWs could be mainly occurred at the tip or at the base of NWs. This study provided useful information in determining the process window for the tip-growth Au-catalyzed ZnO NWs. Besides, a generic growth mechanism, i.e. a combination of Vapor-Liquid-Solid and Vapor-Solid (VLS and VS) mechanism is proposed to explain the tip-growth and base-growth Au-catalyzed ZnO NWs.
Preparation and Characterization of Carbon Nanotube-Based Electrochromic Material
Authors: Zambri Muhammad Shahazmi Mohd , Norani Muti Mohamed , Kait Chong Fai
Published: October 2011

Electrochromic devices (ECD) change light transmission properties in response to voltage during electrochemical redox process. Conducting polymer like polyaniline (PANI) is considered as a good electrochromic material, however, its still exhibit substantial resistivity due to lack of conducting pathway. This paper describes the study in developing electrochromic material that will exhibit higher conductivity by using carbon nanotubes (CNTs) as the filler. Preparation of electrochromic material on FTO glass substrate was done by electrochemical process using mixture of CNTs and PANI in H2SO4. SWCNTs were characterized by Raman spectroscopy. PANI and PANI/CNTs films produced were then characterized using SEM and Hall Effect measurement. From Raman spectroscopy, raw SWCNTs have a typical diameter of 1.3 nm and have good crystallinity with the ratio of 0.12. Increasing the voltage of deposition of PANI, from 1.1–1.7 V, will resulting in increasing the thickness of PANI film from 11‒19 μm. PANI/CNT film was recorded to have higher conductivity than PANI film by 5–7%. From the study, higher conductivity of PANI/CNT film can be achieved by using deposition parameter of 1.3 V for 5 minutes.
Preparation and Characterization of Cu Loaded TiO2 Nanotube Arrays and their Photocatalytic Activity
Authors: Zaki Syazwani Mohd , Sreekantan Srimala
Published: October 2011

This paper described the preparation of Cu loaded TiO₂ nanotube arrays. Firstly, TiO₂ nanotube arrays were formed by anodization. Afterwards, the formed nanotube arrays were incorporated with Cu by wet impregnation method. The soaking time and concentration were varied to obtain an optimum set of parameter for Cu incorporation in TiO₂ nanotubes. After anodization, all samples were annealed at 400°C for 4 hours to obtain anatase phase. The nanotube arrays were characterized by field emission scanning electron microscopy (FESEM), x-ray diffraction (XRD) and x-ray photoelectron spectra (XPS). An average diameter 63.02 nm and length 12.15µm were obtained for TiO₂ nanotubes. The photocatalytic activity of these nanotubes were investigated with methyl orange (MO) and the TiO₂ nanotube prepared in 0.01M of Cu (NO₃)₂ solution within 3 hours demonstrates the highest photocatalytic activity with 83.6% degradation of methyl orange. Keywords: copper doping, wet impregnation, photocatalytic activity
Effect of Milling Time on Microstructure, Crystallite Size and Dielectric Properties of Srtio3 Ceramic Synthesized via Mechanical Alloying Method
Authors: Wong Yick Jeng , Jumiah Hassan , Hashim Mansor , Wong Swee Yin , Yan Leow Chun
Published: October 2011

SrTiO3 sample has been successfully prepared by mechanical alloying (MA) method. The effect of milling time on microstructure, crystallite size and dielectric properties of SrTiO3 were studied. The results revealed that the mean crystallite size of milled powders decreased from 84.56 to 12.87 nm with increasing milling time. However, the average lattice strain of milled powders increased from 0.2 to 0.93% with increasing milling time. A single phase SrTiO3 could not be formed with milling alone and required annealing process. A transformation of anatase-TiO2 to rutile-TiO2 was observed at 16 h of milling. After the milled powders were subjected to sintering process at 1200°C, formation of single-phase SrTiO3-type cubic (Pm-3m) perovskite structure was observed. The peak intensities of the sintered SrTiO3 samples decreased as the milling time was increased. For microstructural observations, the average grain size of the sintered SrTiO3 sample milled for 8 h showed the largest. For dielectric measurements, the dielectric constant of the sintered SrTiO3 sample milled for 8 h showed the highest among others. This could be due to the largest grain size obtained for sintered SrTiO3 sample milled for 8 h. The decrease in the grain size with increasing milling time resulted to the decrease in dielectric constant.
Seed-Mediated Liquid Phase Deposition Method for TiO2 Nanostructure Growth on ITO Substrate: Effect of Surfactant
Authors: Roza Liszulfah , Umar Akrajas Ali , Rahman Mohd Yusri Abd , Salleh Muhamad Mat
Published: October 2011

This paper reports the study on the effect of the surfactants, cetyltrimethylammonium bromide (CTAB) and hexamethylenetetramine (HMT) on the growth of TiO2 nanostructures on ITO surface. TiO2 nanostructures were prepared using a seed-mediated liquid phase deposition (LPD) method. LPD is an electrolysis deposition of metal oxide via hydrolysis of metal-fluoro complex in the presence of boric acid at ambient temperature. In typical case, this method allows the formation of metal oxide film on the substrate surface. Since the properties strongly depend on shape at this length scale, the morphology control growth of TiO2 nanostructures is highly demanded in order to produce desired properties in application. In this work we demonstrate the growth of wire like structure of TiO2 (instead of film) on ITO surface via a seed-mediated liquid phase deposition in the present of surfactant. In typical result, TiO2 with diameter ca. 40 nm at the bottom of nanowire to ca. 10 nm at the nanowire tip can be successfully grown on the surface. The effect of surfactant and their concentration on the growth characteristics of TiO2 nanostructure will be discussed.
Synthesis and Characterization of Superfine Nanostructure Manganese Dioxide Spontaneously Coated onto Carbon Nanotubes
Authors: Salleh Johari Md , Nor Aziah Buang , Othman Muhammad Zamir
Published: October 2011

Manganese dioxide nanostructered (MnO2) was coated onto carbon nanotubes (CNTs) by simple immersion of the CNTs into a KMnO4 aqueous solution. The morphology of the CNTs before and after MnO2 deposition was examined using field emission scanning electron microscopy (FESEM) and high resolution transmission electron microscopy (HRTEM). The superfine coral-like MnO2 deposited and fully covered on the CNTs surface at pH 8. At pH 2 and 6 the MnO2 deposited as the superfine nanorod structure. The superfine MnO2 phase was identified as Birnessite-type MnO2 by X-ray powder diffraction and FESEM. The thermal stability of the superfine nanostructure MnO2 coated CNTs is increase based on the TGA with the weight loss of 4% at 400°C to 900°C.
Synthesis of CuO and ZnO Nanoparticles and CuO Doped ZnO Nanophotocatalysts
Authors: Razali N.Z. , Abdullah A.H. , Haron M.J.
Published: October 2011

Nanocrystalline copper oxide (CuO) particles were precipitated by using different sources of copper salts and oxalic acids. The transformation to monoclinic CuO is achieved by heating the copper precipitate at 300°C for 4 h. Dice-like and flower-like structures were obtained from the effects of by-product’s acidity to the morphology of copper oxalate (Cu (C2O4)). The particle sizes of all samples, determined by transmission electron microscopy (TEM), were in the range of 10-30 nm. 0.5% CuO doped ZnO (CuO-ZnO) nanophotocatalysts were successfully prepared by mixing synthesized CuO nanoparticles with synthesized ZnO in absolute methanol. No significant changes in morphology were observed between the undoped and doped ZnO except for a higher surface area obtained for CuO doped ZnO. The doping of CuO on ZnO also resulted in enhanced photocatalytic performance of ZnO in the photodegradation of methyl orange dye.
Effect of the Precursor Solution Concentration of CuI Thin Film Deposited by Spin Coating Method
Authors: Nur Amalina Muhamad , Azman Muhammad Atiq , Rusop Mohamad Mahmood
Published: October 2011

In this research, the effect of precursor concentration of CuI thin film deposited by spin coating method was studied. The wide band gap p-type semiconductor CuI thin film was prepared by mixing the CuI powder with 50 ml of acetonitrile as a solvent. The CuI concentration varies from 0.05M to 0.5M. The speed for spin coating is 1000 rpm for 60 seconds. After the deposition the CuI thin films were annealed at 150°C. The result shows the CuI thin film properties strongly depends on its precursor concentration. Thickness between 33.65 nm - 441.25 nm was obtained as the concentration increased. The increment of thickness affected the electrical property with resistivity of about 10-6 Ω.cm and 101 Ω.cm was observed for all the CuI thin films. For optical properties, the transmittance decreased with high concentration as high amount of CuI particle were observed in the thin films. From the transmittance, the absorption coefficient of 10-6 m-1 and optical band gap of 3.10 and 3.50 eV for all the films were observed using Tauc’s plot.
Properties of ZnO Nanorods Arrays Growth via Low Temperature Hydrothermal Reaction
Authors: Nur Syafinaz Ridhuan , Lockman Zainovia , Abdul Aziz Azlan , Khairunisak Abdul Razak
Published: October 2011

This work describes properties of 1-D ZnO nanorods arrays growth using low temperature hydrothermal method on a seeded substrate. The properties of ZnO seed were studied by varying thermal oxidation temperature from 250-450°C. The formation of ZnO nanorods was studied by varying the growth time during hydrothermal process. The optimum oxidation temperature to produce seeded ZnO template was 400°C. The formation of ZnO nanorods was further studied by varying hydrothermal reaction growth time from 1 to 24 hours. The optimum hydrothermal growth time of 4 hours produced blunt tip-like nanorods with length of ~735 nm and top diameter of ~66 nm. I-V characteristics of ZnO nanorods photodetector in dark, ambient light and UV light were also studied. The change in the photoconductivity under UV illumination was found to be 1 order of magnitude higher compared to dark and ambient light. With an incident wavelength of 370 nm and applied bias of 3V, the responsivity of photodetector was 5.0 mA/W, which was higher compared to other reported works. The increase of photosensitivity indicated that the produced ZnO nanorods were suitable for UV photodetector applications.
Irradiation Modification of Epoxidized Natural Rubber/Ethylene Vinyl Acetate/Carbon Nanotubes Nanocomposites
Authors: Norazlina Mohamad Yatim , Faridah Yusof , Ratnam Chantara Thevy , Sopyan Iis
Published: October 2011

The effect of irradiation on the mechanical properties of Epoxidized Natural Rubber/Ethylene Vinyl Acetate/Carbon Nanotubes (ENR/EVA/CNTs) nanocomposites were investigated. CNTs at various amount (2, 3, 4 and 6 wt%) were incorporated into ENR50 by solvent casting method. The ENR/CNTs were then blended with EVA by mixing in a Brabender Plasticoder at 120°C. Next, the samples were irradiated by using electron beam with 3 MeV electron beam machine in a dose range of 50 to 200 kGy. The mechanical properties such as tensile strength (Ts), modulus at 100% elongation (M100), elongation at break (Eb) and hardness of reinforced ENR/EVA/CNTs nanocomposites were studied as a function of radiation dose. It was found that, the Ts and M100 has increased almost 2 times compared to the nanocomposites without irradiation up to 150 kGy dose of radiation, and a downward trend thereafter. Gel fraction further confirmed the powerful energy of electron beam radiation result in irradiation-induced crosslinking and further enhanced mechanical properties of the nanocomposites.
Silver Nanoparticles - Graphene Oxide Nanocomposite for Antibacterial Purpose
Authors: Chook Soon Wei , Chia Chin Hua , Sarani Zakaria , Ayob Mohd Khan , Chee Kah Leong , Neoh Hui Min , Huang Nay Ming
Published: October 2011

Graphene oxide (GO) sheets, a single layer of carbon atoms which can be served as substrates for fabricating metallic nanoparticles-GO nanocomposites. In this study, the nanocomposite of silver nanoparticles and graphene oxide were produced via in-situ synthesis and with the addition of chitosan to investigate the formation of silver nanoparticles on the graphene oxide sheets. XRD and UV-Vis studies confirmed the formation of silver nanoparticles on GO sheets, while TEM and FESEM images presented the loading of silver nanoparticles on the GO sheets. The degree of loading and distribution of the silver nanoparticles on the graphene oxide were depend on the method during the formation of silver nanoparticles. The nanocomposites can be potentially used in food packaging and biomedical applications.
Effect of MgO Nano Particle on Mechanical Property and Microstructure of ZTA Ceramic Composite
Authors: Azhar Ahmad Zahirani Ahmad , Mohamad Hasmaliza , Ratnam Manimaran , Ahmad Zainal Arifin
Published: October 2011

The mechanical properties and microstructure of zirconia-toughened-alumina ceramic composite doped with nanoparticle of MgO is investigated. The nanoMgO weight percent was varied from 0.3 wt % to 1.3 wt %. Each batch of composition was mixed using ultrasonic cleaner and mechanical stirrer, uniaxially pressed and sintered at 1600 °C for 4 h in pressureless conditions. Analysis of bulk density, Vickers hardness and microstructural observation has been carried out. Results of Vickers hardness increased linearly with addition of more nanoMgO until a certain composition. Maximum Vickers hardness obtained was 1740HV with 1.1 wt % MgO. Furthermore, microstructural observations show that the Al2O3 grain size depends on the particle size of MgO, and is directly related to its hardness property.
Nanoscale Investigation of Nb-Doped CaCu3Ti4O12 Grains
Authors: Sulaiman Muhammad Azwadi , Hutagalung Sabar Derita , Ahmad Zainal Arifin
Published: October 2011

CaCu3Ti4O12 (CCTO) is a promising material for microelectronic and microwave device applications due to its unique properties that posses high dielectric constant in the wide temperature range. In this work, atomic force microscopy (AFM) and scanning electron microscopy (SEM) analyses were applied for nanoscale imaging of Nb-doped CCTO grains. The Nb-doped CCTO pellets (CaCu3Ti4-xNbxO12+x/2; x = 0, 0.01, 0.03, 0.05, 0.1) were prepared via solid state reaction method and thermally etched at 940°C for an hour. From AFM and SEM images found that tiny bumped as well as terrace type domains are distributed within a grain. The domain size is ranging from 20 to 180 nm measured by AFM. The existence of domains on grain will produce grain boundary and domain boundary resistance inside CCTO. Both domain and grain resistance are believed to strongly influence the electrical properties of CCTO.
Structural Properties of Nanocrystalline PbS Thin Films Prepared by Chemical Bath Deposition Method
Authors: Obaid A.S. , Mahdi M.A. , Ramizy Asmiet , Hassan Z.
Published: October 2011

Nanocrystalline PbS thin films were prepared using chemical bath deposition method on glass substrates, together with lead acetate as a source of lead ions (Pb2+) and thiourea as a source of sulfide ions (S2-) with different molar concentrations. The structural properties of thin films were studied using X-ray diffraction.The patterns showed a polycrystalline structure, and the preferred orientation changed along (111) and (200) planes .The grain size of the thin films varied from 27 to 41 nm. The crystallites were under strain, which varied between 0.054 and 0.3. Scanning electron microscope images showed that all the films have uniform surface morphology over the entire glass substrate and that the films were of good quality.
Effect of PEG Molecular Weight on the TiO2 Particle Structure and TiO2 Thin Films Properties
Authors: Zainab M. , Abd Razak Jeefferie , Masrom A.K. , Rosli Zulkifli Mohd
Published: October 2011

This research, deals with modification of sol gel process for the synthesis of porous TiO2-PEG thin films with good structural integrity for environmental self-cleaning applications. Relatively, by adding the PEG with various molecular weights (300, 400, and 600) could influence the formation of TiO2 films structure and adhesion. Moreover, the formation of porous TiO2 associated with larger pores will accelerate the mass transfer of the treated contaminants in the larger pore channels. The advantages of the unique structures of as-prepared TiO2₂ films in the application of environmental self-cleaning systems are extensively studied by characterizing the produced films using various advanced characterization tools. Adhesion of TiO2 thin films become smooth and better surface with increasing the coating layers. The X-ray Diffraction spectrum of prepared coating shows present of anatase phase as major phase.
Synthesis and Characterization of New Bolaform Surfactant from Palm Oil Derivative
Authors: Goh S.C. , Chin S.Y. , Lee L.M.S. , Yarmo Mohd Ambar , Nik Yusof N.I.
Published: October 2011

In this research, new chemistry is explored through a simple, efficient and cheap method to synthesize new surfactants from palm oil fatty acids. Oleic acid, which is one of the major fatty acids in palm oil, has been used as a starting material for the synthesis of surfactants. This study focuses on the synthesis and characterization of bolaform surfactants from oleic acid. For this purpose, two steps reaction will be carried out: Firstly, consisted of hydrobromination of oleic acid followed by reaction of 10-bromo-octadecanoic acid with ethane-1,2-dithiol and butane-1,2-dithiol. During the first stage of the reaction, hydrobromination of oleic acid was carried out by adding hydrobromic acid into the oleic acid. The reaction was carried out in benzene as solvent at 30°C and atmospheric pressure. This reaction gives 73% yield of 10-bromo-octadecanoic acid and it yield a black brownish liquid which have the m/z 363.2056 by ESI-MS(ToF) and –CH2-CHBr-CH2-shift (4.02 ppm) was well defined in 1H-NMR. The separation of 10-bromo-octadecanoic acid was done through thin layer chromatography (TLC) with chloroform and methanol as the eluent and silica plate grade 60 F254 as the stationary phase. The second stage of reaction was reacting the 10-bromo-octadecanoic acid with ethane-1,2-dithiol and butane-1,2-dithiol in THF as the solvent and 1,8-Diazabicyclo [5.4.0] undec-7-ene (DBU) as the catalyst respectively. These reactions were carried out at 30°C and atmospheric pressure. Product obtained was a two layers black brownish liquid with white colour precipitate gives m/z: 659.4813 for ethane-1,2-dithiol and m/z:686.5278 for butane-1,4-dithiol respectively using ESI-MS (ToF) mass spectroscopy. Separation was done on both bolaform surfactants through thin layer chromatography (TLC) with hexane and ethyl acetate as eluent and silica plate grade 60 F254 as stationary phase, and finally followed by column chromatography. These two new surfactants will be tested for their physical-chemical properties as well as apply on nanomaterial stabilizer.
The Research of Livestock Carrying Capacity of Rangeland Ecosystem in HulunBuir
Authors: Wang Rui Jie , Yang Lian Wei
Published: October 2011

Due to population pressure and over-grazing, ecological degradation of the rangeland in HulunBuir becomes more and more serious in past decades. To balance pasture grazing activities and ecosystem sustainability, monitoring grass productivity of the rangelands and livestock carrying capacity are very necessary. Grassland yield is the basis of developing livestock, net primary production (NPP) is an important parameters in determining carrying capacity. Using MODIS remote sensing data, we estimated the NPP of grassland ecosystem of HulunBuir in 2006. The total NPP of grassland ecosystem in HulunBuir was 2.9×1013 gC/a in 2006, with an average of 261.01gC/m2•a. Then we based on the estimated NPP to calculate the optimal carrying capacity which was 765.41 ten thousands sheep units. The actual carrying capacity was 1838.45 ten thousands sheep units, total overloading was 1073.04 ten thousands sheep units. The serious regions of overloading were Arong Banner with 325.45 ten thousands sheep units, Zlantun City with 270.72 ten thousands sheep units, Molidawadahanr Autonomous Banner with 254.71 ten thousands sheep units. The carrying capacity of Oroqin Autonomous Banner, Genhe City and Erguna City were scarcity, there were great potential to excavate in livestock.
Radiation Protection of Carboxymethylation of an Acid Polysaccharides Extracted from Auricularia Auricula against Uvb In Vitro
Authors: Zhang Hua , Wang Zhen Yu , Fan Zi Luan , Yang Xin , Wang Xue , Zhang Ning
Published: October 2011

This paper reports on a water-soluble acid polysaccharide (AAP) and in how it was extracted from Auricularia auricular, acquired by CTAB, and prepared it’s carboxymethylation. Chemical characterization by high-performance liquid chromatography/gel permeation chromatograph (HPLC/GPC), Fourier transform infrared (FT-IR) spectrometer and gas chromatography–mass spectrophotometer (GC–MS) were investigated. Chemical analysis indicated that C AAAP was composed of arabinose, xylose, mannose, glucose and galactose, with the molar ratio at 0.04: 0.13: 1.00: 0.59: 0.29. Moreover, radiation protection against UVB in vitro indicated that at the dose range of 200–500 μg/mL, C AAAP enhanced the protection of HepG2 cells against UVB cytotoxicity than AAAP. However, but at the dose range of 50–150 μg/mL the result was just opposite.
Preliminary Research on Differentially Expressed Proteins in Hippocampus of Rats Induced by Chronic Immobilization Stress and the Effect of Xiaoyaosan
Authors: Kou Mei Jing , He Da Cheng , Zhang Pei , Chen Jia Xu , Wang Shao Xian , Zhao Xin , Bai Ming Hua , Guo Xiao Ling
Published: October 2011

To select differentially expressed proteins in hippocampus of rats with pattern of Liver Qi stagnation and Spleen deficiency (LQSSD) induced by chronic immobilization stress (CIS), by applying the technique of protein chip and surface-enhanced laser desorption ionization time of flight mass spectrometry (SELDI-TOF-MS). Methods: The rats with pattern of LQSSD according to traditional Chinese medicine (TCM) were replicated by the method of CIS. After twenty-one days’ stress, the protein chip weak cation CM10 and SELDI-TOF-MS were applied in order to do mass spectral analysis of the proteins acquired from the three groups: normal control group, 21 days model group, and Xiaoyaosan (XYS) treatment group. Bio Marker Wizard software were adopted to analyze the differentially expressed proteins. Results: Five differentially expressed proteins were selected between the control group and model group, and they were all highly expressed in the model group. Thirteen one were selected between control group and treatment group, among which 3 were highly expressed in the treatment group, and 10 were highly expressed in the control group. Only 1 differentially expressed protein was selected between the treatment group and the model group and it was highly expressed in the latter. Conclusion: The differentially expressed proteins may be the specific marker proteins in hippocampus of rats with pattern of LQSSD induced by CIS. TCM formula XYS may be an effective intervention for protein expression in hippocampus of rats with pattern of LQSSD.
Screening of Actinomycetes with High Producing Xylanase
Authors: She Yuan Li , Li Xiu Ting , Sun Bao Guo , Lv Yue Gang , Song Hong Xia
Published: October 2011

Xylanase has a wide range of potential biotechnological applications in pulp and bleaching processes, textile industries, food and bread making, fruit juice clarification and so on. In order to explore and utilize xylanases using actinomycetes, collected dozens of soil samples beneath decaying wood or leaf debris of different parts of China, 102 xylanase producing actinomycetes were isolated by plate screening with home-made corncob xylan as the sole carbon source. All strains degraded xylan and produced evident xylan hydrolyzed circles. 37 actinomycetes were selected by shake flask cultivation, and among them 7 stains with high producing xylanase were submerged fermentation again. Xylanase activities of 7 strains except L1904 (158U/ml) were all beyond 200U/ml and stable. L2001 as the most promising strain, xylanolytic activity of which was 815U/ml. The project set up foundation for the further study in the future.
The Bioactivitiy of Essential Oil from Ailanthus altissima Swingle (Sapindales: Simaroubaceae) Bark on Lasioderma serricorne（Fabricius) (Coleoptera: Anobiidae)
Authors: Lü Jian Hua , Shi Yan Li
Published: October 2011

The essential oil was extracted by Soxhlet method with anhydrous diethyl ether from Ailanthus altissima Swingle (Sapindales: Simaroubaceae) bark, a traditional Chinese herbal plant, and its repellent and its fumigant activity was investigated against Lasioderma serricorne （Fabricius）(Coleoptera: Anobiidae) adults. A. altissima bark oil had extremely strong repellent activity against L. serricorne adults with the percentage repellency 93.7, 87.8 and 76.1% after 24, 48, and 72 h exposure, respectively. A. altissima bark oil also possessed high fumigant activity against L. serricorne adults with the corrected percentage mortality 100% at 8 µL/L air within 48 h exposure.
Buckling Analyses of the Antisymetrical Composite Laminate Plate with a Crack from Circular Notch
Authors: Hamani N. , Ouinas Djamel , Benderdouche N. , Sahnoun Mohamed
Published: October 2011

In this study, an analysis of buckling was carried out on composite rectangular plates with and without circular notch by using the finite element method. The graphite/epoxy laminated plates were arranged antisymmetrically in the following ordered way [(θ/-θ)2]s. The buckling strength of the asymmetrical laminated plates subjected to uniaxial load is determined as a function of fiber orientation. The results show that whatever the notch radius, the buckling load is almost stable. The cumulated effect due to the presence of the longitudinal and transverse cracks as well as a circular notch reduces the buckling load considerably, which increases the risk of the fracture.