bluuebunny/crossref_metadata_2025 huggingface dataset:
Microscopic Studies of Gold Deposit of Southern Ashaly in Eastern Kazakhstan
Authors: Baibatsha Adilkhan , Dyussembayeva Kulyash , Kassenova Aimkhan
Published: November 2013

The gold-sulfide deposit Southern Ashaly is localized in carbonaceous terrigenous formation (black shale strata) of the middle carboniferous (Bukon suite, which is the ore-hosting for super large deposit Bakyrchik). The Southern Ashaly is at the exploration stage and according to preliminary estimates of the expected resources belongs to a large deposit in scale. Ore gold mineralization of such level as Southern Ashaly in southwestern Kalba is found for the first time and gives hope for the discovery of such objects in the Boko Vassilyevskoye ore field. Ore-hosting at the field Southern Ashaly is carbonaceous terrigenous formation of the middle carboniferous, with no visible signs of volcanic formations. But, it was revealed, at microscopic research by us, paragenetic relation of the gold mineralization with small intrusions of plagiogranites and zones of plagiogranite porphyry dykes and found volcano-sedimentary rocks (aleuritic tuffsandstone, tuff breccia) which have undergone hydrothermal-metasomatic changes. The vein-disseminated gold-sulfide mineralization is associated with beresitizated plagiogranites and plagigranite-porphyries and hydrothermally altered tuff sandstones, tuff breccia and carbonaceous shales. Southern Ashaly unlike Bakyrchik deposit which contains invisible gold in sulfides, all the gold is concentrated in the pyrite mainly in the form of micro-sized (1-5 µm or less) in arsenopyrite is noted rarely.
Anodic Dissolution Behaviour of Tungsten Carbide Scraps in Ammoniacal Media
Authors: Katiyar Prvan Kumar , Randhawa Navneet Singh , Hait Jhumki , Jana Ranajit Kumar , Singh K.K. , Mankhand T.R.
Published: November 2013

In the present paper, potentiodynamic studies of WC scrap have been carried out as these studies give better idea about the anodic dissolution behaviour of the scrap material to recover the metal values. However, it has been seen that anodic passivation retards the dissolution of the scrap and adversely affects the recovery of metals. To minimize the passivity and to increase the anodic dissolution, some chemicals are often used as additives. Two different electrolytes namely hydrochloric acid and aqueous ammonia at varying concentrations had been employed for the above studies. The additives citric acid and oxalic acid were added to the acidic electrolyte whereas ammonium chloride, ammonium carbonate and ammonium sulphate were added in different concentration to the ammoniacal electrolyte. The studies revealed that 2% citric acid in 1N HCl was the optimum to achieve maximum anodic dissolution (current) of WC scrap. On the other hand, 5% NH4Cl was found suitable to obtain maximum anodic dissolution (current) in the ammoniacal (150 g/L) medium. The potentiodynamic studies were followed by the actual electrodissolution experiments in an electrolytic cell with the help of a rectifier. The W and Co recoveries were encouraging.
Arsenic Removal from Spent Liquor Generated during Processing of Vanadium Sludge
Authors: Pramanik Swati , Sahu Sushanta K. , Meshram Pratima , Pandey Banshi Dhar
Published: November 2013

During production of ammonium meta-vanadate from vanadium sludge an arsenic containing (~2.2g/L) spent liquor is generated. Safe disposal of such liquor without arsenic contamination to the environment is essential. Therefore, various methods such as ion-exchange, adsorption, solvent extraction and precipitation were applied for recovery of arsenic from the spent liquor. Based on the Eh-pH diagram of As-H2O, the arsenic based species were delineated. For ion exchange Lewatit FO 36 and Amberlite IRA 400 Cl- resins were used to extract arsenic from the spent liquor. With Lewatit FO 36 a maximum of 20% arsenic was recovered at A/R ratio of 50. Amberlite IRA 400 Cl- on the other hand didnt extract arsenic at all. A two stage solvent extraction process using TBP as an extractant, with a recovery of 97% arsenic from the spent liquor was developed. From the loaded TBP almost complete stripping of arsenic was obtained with 0.1-0.5M NaOH solution. Precipitation of arsenic from the spent liquor as copper arsenate or iron arsenate was also examined. During the fixation of arsenic with iron, 70% arsenic was recovered in the precipitate. This process needs to be evaluated further with the aim of using the iron hydroxide containing arsenic for different applications.
Effect of Trace Added Sn on Mechanical Properties of Al-Zn-Mg Alloy
Authors: Sadhukhan Sanjoy , Kundu Molay , Ghosh Manojit
Published: November 2013

The heat treatable 7xxx series Al alloys (Al-Zn-Mg) show good combination of tensile properties through precipitation hardening. Similar to Al-Cu alloy minor addition of Sn in this alloy also influences its structure and properties. The hardness improves after natural ageing and further improves after duplex ageing. Duplex ageing refines the grains also. SEM-EDX results indicate that β-Sn is present in the form of precipitates. DSC results indicate that Sn suppresses the formation of GP zone and the stability of intermediate η phase is higher.
Heat Transfer Performance of Different Nanofluids Flows in a Helically Coiled Heat Exchanger
Authors: Khairul Mohammad Alam , Saidur Rahman , Hossain Altab , Alim Mohammad Abdul , Mahbubul Islam Mohammed
Published: November 2013

Helically coiled heat exchangers are globally used in various industrial applications for their high heat transfer performance and compact size. Nanofluids can provide excellent thermal performance of this type of heat exchangers. In the present study, the effect of different nanofluids on the heat transfer performance in a helically coiled heat exchanger is examined. Four different types of nanofluids CuO/water, Al2O3/water, SiO2/water, and ZnO/water with volume fractions 1 vol.% to 4 vol.% was used throughout this analysis and volume flow rate was remained constant at 3 LPM. Results show that the heat transfer coefficient is high for higher particle volume concentration of CuO/water, Al2O3/water and ZnO/water nanofluids, while the values of the friction factor and pressure drop significantly increase with the increase of nanoparticle volume concentration. On the contrary, low heat transfer coefficient was found in higher concentration of SiO2/water nanofluids. The highest enhancement of heat transfer coefficient and lowest friction factor occurred for CuO/water nanofluids among the four nanofluids. However, highest friction factor and lowest heat transfer coefficient were found for SiO2/water nanofluids. The results reveal that, CuO/water nanofluids indicate significant heat transfer performance for helically coiled heat exchanger systems though this nanofluids exhibits higher pressure drop.
Investigation of Heat Transfer Performances of Nanofluids Flow through a Circular Minichannel Heat Sink for Cooling of Electronics
Authors: Sohel M.R. , Rahman Saidur , Mohd Sabri Mohd Faizul , Elias M.M. , Khaleduzzaman S.S.
Published: November 2013

Nanofluid is the suspension of nanoparticle in a base fluid. In this paper, the heat transfer performances of the nanofluids flow through a circular shaped copper minichannel heat sink are discussed analytically. Al2O3-water, CuO-water, Cu-water and Ag-water nanofluids were used in this analysis to make comparative study of their thermal performances. The hydraulic diameter of the minichannel is 500 μm and total block dimension is 50mm× 50mm× 4mm. The analysis is done at different volume fractions of the nanoparticle ranging from 0.5 vol.% to 4 vol.%. The results showed that the heat transfer performance increases significantly by the increasing of volume fraction of nanoparticle. Ag-water nanofluid shows the highest performance compared to the other nanofluids. So, this nanofluid can be recommended as a coolant flow through a circular minichannel for cooling of electronic heat sink.
Thermoluminescence Properties of Nanostructured Calcium Borate as a Sensitive Radiation Dosimeter for High Radiation Doses
Authors: Erfani Haghiri Maryam , Saion Elias , Soltani Nayereh , wan Abdullah Wan Saffiey
Published: November 2013

The crystalline calcium tetraborate (CaB4O7) nanoparticles were synthesized using a combination of facile co-precipitation and thermal treatment. The synthesized phosphor nanoparticles were found to possess a monoclinic nanostructure of particle size of about 8 nm. The thermoluminescence (TL) glow curve of the nanoparticles shows a single peak centred at about 150°C. The TL nanophosphor revealed an excellent dosimetric response with a respectable linearity in the dose range of 0.05 to 1000 Gy, which is wider than its counterparts prepared by non nanosynthesis methods. They exhibited good luminescence efficiency and wide range linearity, suggesting the present phosphor nanoparticles may be considered as a suitable candidate for the dosimetric applications.
Investigation on the Morphology of Sintered Silver Nanomaterial for Electronic Packaging Application
Authors: Durairaj Rajkumar , Das M. , Morris E. , Namasivayam Satesh
Published: November 2013

Silver nanoparticles are seen as a possible replacement for high temperature solders containing 90-95 wt.% Pb, which is widely used in various applications e.g. automotives. These high temperature solders have been exempted from the Restriction of Hazardous Substances (RoHS) Directive due to very limited drop-in replacement for the high temperature solders. Although the effect of sintering temperature of silver nanoparticles has been studied, the mechanism involved in the changes in the morphology of the particles and interfacial reaction with the substrate as a function of sintering temperature must be understood. In this study the effect of sintering temperature on the morpohology of Ag nanoparticles is discussed. The Scanning Electron Microscopy (SEM) analysis was used to analyze the changes in morphology of silver particles agglomerates with sintering temperatures. Results showed necking of the nanosilver powder, which indicated the occurrence of sintering through grain boundary diffusion process. Meanwhile, the micro-silver powder showed agglomeration of particles but no necking was observed. The study has shown that the Ag agglomerates was observed to undergo various changes to the particle morphology with different sintering temperatures.
Nanofluids for Thermal Performance Improvement in Cooling of Electronic Device
Authors: Khaleduzzaman S.S. , Rahman Saidur , Selvaraj Jeyraj , Mahbubul I.M. , Sohel M.R. , Shahrul I.M.
Published: November 2013

Nanofluid is a promising coolant for high-heat dissipation electronics device or system. The effect of nanofluids as thermal performances on a rectangular shape microchannel heat sink (MCHS) is analytically studied. Al2O3, SiC, and CuO nanoparticles dispersing in water were considered for analysis. A steady, laminar, and incompressible flow with constant heat flux was assumed in the channel. Nanofluids with concentrations of 0.5 to 4.0 vol. % were analyzed at two different inlet velocities of 0.5 m/s and 3.0 m/s. The results showed that highest thermal conductivity enhancement was 12.45% by using SiC-water nanofluids. In the case of Al2O3-water and CuO-water nanofluids maximum improvement were 11.98% and 11.36%, respectively for 4.0 vol. % of nanoparticle concentration. Furthermore, nanofluids as a coolant instead of water showed a highest improve of heat flux 8.51% for water-CuO, and 6.44% and 5.60% increase for Al2O3-water and SiC-water, respectively. The maximum pumping power found 0.33 W at 3 m/s and 0.0091 W at 0.5 m/s for the same concentration of 4.0 vol. % for all of these nanofluids.
Influence of RF Magnetron Sputtering Pressure on the Structural, Optical, and Morphological Properties of Indium Tin Oxide Nanocolumns
Authors: Najwa S. , Shuhaimi A. , Ameera N. , Hakim K.M. , Sobri M. , Mazwan M. , Mamat M.H. , Musa M.Z. , Rusop Mohamad
Published: November 2013

In the present study, ITO nanocolumn was successfully deposited onto a glass substrate by RF magnetron sputtering. The effect of deposition pressure was investigated. X-ray diffraction analysis indicates that the intensity of the (400) peak orientation is highest at sputtering pressure of 5 mTorr. The results from UV-visible (UV-vis) spectroscopy revealed that the optical transmittance above 80 % was obtained from the all samples in the visible range of 400-800 nm. The larger grain size was observed from the top view of field emission scanning electron microscopy (FESEM) image as the sputtering pressure was increase. Dense nanocolumn arrays were obtained from the sample deposited at sputtering pressure of 5 mTorr. The surface roughness were decreased at high sputtering pressure of 10 mTorr was observed from atomic force microscopy (AFM) surface morphology. The electrical properties were obtained using standard two-point probe measurements. The lowest electrical resistivity was determined from the sample that prepared at sputtering pressure of 5 mTorr.
Micro-Raman, Optical and Impedance Characteristics of CNT-Substituted Acrylate/CNT Nanocomposite Thin Film
Authors: Shamsudin M.S. , Mahmud Muhammad Rashid , Husairi F.S. , Harun M.K. , Suriani A.B. , Abdullah Saifollah , Rusop M.
Published: November 2013

Carbon nanotube (CNT) has been synthesized using camphor oil as a starting material via two-stage catalytic chemical vapor deposition. The as-synthesized CNT was then incorporated into acrylate matrix by suspension polymerization method, using various loading of CNT (as a filler) varied from 0.2 to 1.0 g with 0.2 g weight interval in the nanocomposite thin film. The acrylate/CNT nanocomposite thin film was characterized using micro-Raman, ultraviolet-visible and impedance spectrometer. As confirmed, the various loading of CNT had a significant impact on structural, optical and impedance characteristics. The paper contributes the recent achievements in material progress of CNT/polymer nanocomposite.
Fundamentals of Two-Dimensional Crystallographic Carbon Form and its Future Directions: A Review
Authors: Shamsudin M.S. , Fishlock Sam Jeffery , Ahmad Rafidah , Rusop Mahmood Mohamad , Sanip Suhaila M. , Pu Suan Hui
Published: November 2013

Intrinsic graphene is defined as a one-atomic-thick planar film of sp2-hybridized carbon atoms which are densely packed in a hexagonal crystal lattice structure. This material has opened up a host of possibilities with its extraordinary properties and is expected to be utilized in many practical applications. This article reviews the recent advances in growth techniques for the production of graphene. The main characterization techniques for graphene are highlighted. Finally, the critical issues relating to potential health risk, safety and toxicity of graphene have also been highlighted.
Performance of Ultraviolet Photoconductive Sensor Based on Aluminium-Doped Zinc Oxide Nanorod-Nanoflake Network Thin Film Using Aluminium Contacts
Authors: Mamat M.H. , Md Sin Nor Diyana , Saurdi I. , Hafizah N.N. , Malek Mohd Firdaus , Asiah Mohd Nor , Khusaimi Zuraida , Habibah Zulkefle , Nafarizal Nayan , Rusop M.
Published: November 2013

In this research, we fabricated UV photoconductive sensor using aluminium (Al)-doped ZnO nanorod-nanoflake network thin film. These nanostructures were deposited on the seed-layer-coated glass substrate using sonicated sol-gel immersion method. By using Al contacts, it was found that the performance of the UV photoconductive sensor is very good. The responsivity of the device was 46.4 mA/W with sensitivity of 17.5 under 365-nm UV light (5 mW/cm2) at bias voltage of 10 V. Our study revealed that these nanostructures are very promising material for the UV photoconductive sensor applications.
Investigation of Stress and Electrical Properties of Air-Annealed and Oxygen-Annealed Aluminium-Doped Zinc Oxide Nanorod Arrays
Authors: Mamat M.H. , Md Sin Nor Diyana , Saurdi I. , Hafizah N.N. , Malek Mohd Firdaus , Asiah Mohd Nor , Khusaimi Zuraida , Habibah Zulkefle , Nafarizal Nayan , Rusop M.
Published: November 2013

In this research, we prepared aluminium (Al)-doped ZnO nanorod arrays on the glass substrate using sonicated sol-gel method. These nanorod arrays were annealed at 500 °C in air and oxygen environment using thermal furnace. Field emission scanning electron microscopy (FESEM) image reveals that nanorod arrays were deposited vertically aligned on the substrate. The stress characteristics of air-annealed and oxygen-annealed Al-doped ZnO nanorod arrays were investigated using Raman spectroscopy and X-ray diffraction (XRD) measurement. The electrical properties of the samples were investigated using two-probe current-voltage (I-V) measurement system. The results show that annealing atmospheres greatly influenced the stress and electrical properties of the nanorod arrays.
Formation of ZnO Nanoparticulate Thin Film: Sol-Gel Synthesis and Characterisation
Authors: Malek Mohd Firdaus , Mamat Mohamad Hafiz , Zaihidi Musa Mohamed , Sahdan Mohd Zainizan , Khusaimi Zuraida , Mahmood Mohamad Rusop
Published: November 2013

ZnO thin films have been prepared sol gel dip coating method using zinc acetate dehydrate (Zn(CH3COO)2·2H2O, Merck) as cation source, 2-methoxyethanol (C3H8O2, Merck) as solvent and monoethanolamine, MEA (C2H7NO, R&M) as sol stabilizer. Film deposition was performed by dip-coating technique at a fixed deposition rate on Corning 7740 glass substrate. The effect of sol concentration on the properties of the thin films is discussed. The effect of the sol concentration on produced ZnO films was found to be significant. X-ray analysis showed that thin films were preferentially orientated along the c-axis direction of the crystal. Besides, the films had a transparency of greater than 80% in the visible region for sol–gels with a zinc content of up to 0.8 M and exhibited absorption edges at ~375 nm.
Fabrication of Silicon Nanowires by Electron Beam Lithography and Thermal Oxidation Size Reduction Method
Authors: Md Nor Mohammad Nuzaihan , Hashim Uda , Nazwa Taib , Adam Tijjani
Published: November 2013

A simple method for the fabrication of silicon nanowires using Electron Beam Lithography (EBL) combined with thermal oxidation size reduction method is presented. EBL is used to define the initial silicon nanowires of dimensions approximately 100 nm. Size-reduction method is employed for reaching true nanoscale of dimensions approximately 20 nm. Dry oxidation of silicon is well investigated process for self-limited size-reduction of silicon nanowires. In this paper, successful size reduction of silicon nanowires is presented and surface topography characterizations using Atomic Force Microscopy (AFM) are reported.
Effect of Gas Flow Rate on the Properties of Amorphous Carbon Thin Films Prepared by Thermal CVD Using Camphoric Carbon Precursor
Authors: Dayana K. , Fadzilah A.N. , Ishak A. , Siran Yosri M. , Rejab Syahril Anuar M. , Asis Ahmad Jaril , Tahirruddin Syawaluddin , Rusop M.
Published: November 2013

Amorphous carbon (a-C) thin films have been prepared by a simple thermal CVD using camphor oil as precursor. The effects of argon gas flow rate on electrical, optical and structural properties of a-C thin films have been investigated. The a-C thin films were characterized by using current-voltage (I-V) measurement, UV-Vis-NIR spectroscopy, Raman and FTIR spectroscopy. The I-V study reveals that the electrical conductivity was increased with increasing argon gas flow rate. It was found that the optical band gap decreased from 0.88 to 0.42 eV as gas flow rate increased which indicates a microstructural disorder at different gas flow rate. Raman and FTIR studies reveal the amorphous structures which consist of a mixture of sp2 and sp3 bonded carbon atoms.
Properties of O-Doped CuI Thin Films by Chemical Vapor Deposition (CVD) at Different Deposition Flow Rate
Authors: Muhamad Nur Amalina , Mat Firdaus Che , Rusop M.
Published: November 2013

The effect of oxygen doping to the properties of CuI thin films was studied. The doping of oxygen to the CuI thin films was done by using single furnace chemical vapor deposition (CVD) method at different oxygen gas flow rate (e.g 10, 20, 30, 40 and 50 sccm). The CuI thin film was first deposited by using mister atomizer at constant CuI solution concentration of 0.05M. The surface morphology and electrical properties of O-doped CuI was studied. The field emission scanning electron microscopy (FESEM) was used to observe the morphology of O-doped CuI thin films. The FESEM images revealed that all the CuI thin films deposited were uniform with the existence of nanostructured CuI particle. The EDX measurement confirm the existence of Cu:I in the films and also the variation of oxygen ratio in the CuI thin films as the oxygen was introduced. The resistivity of 101 Ωcm to 103 Ωcm at constant voltage of-5V to 5V was obtained for the O-doped CuI thin films.
Augmentation of EFB Fiber Web by Nano-Scale Fibrous Elements
Authors: Ghazali Arniza , Mohd Zukeri Mohd Ridzuan Hafiz , Wan Rosli W.D. , Azhari Baharin , Ibrahim Rushdan , Ahmed Mohamed Issam , Ahmad Tanweer , Khan Ziya Ahmad
Published: November 2013

Treatment of the abundant oil palm empty fruit bunches with alkaline peroxide chemicals and subsequent fibrillation at varying mechanical energies resulted in favourable morphological changes of the generated fibers. The produced fibrous mass composed of intensely fibrillated elements ranging from micro to nanodiameter fibrils. nanofibrils and webs of nanofibrils were factors contributing to the functionality of the fibrous mass as fibre web augmentation elements. Profound improvement in fiber network is particularly attributable to the ability of the collected elements to fill up inter-fiber gaps and this was attributable to the micro elements in the form of micro fines, segmented micro-fibrils and webs of nanofibrils. The uniquely generated thin layers of nanofibril webs (TN-webs), were found to increase fiber web density by gluing multiple layers of fibers, together. Having landed on the surface of micro-fiber web, these TN-webs were identified as responsible for the masking effects of the underlying micro-fibres. Under such condition, fibers were observed to coalesce, suggesting also an augmented fiber network as evident from the 130% increase in tensile index and a 450% enhancement in burst index of the resultant fiber web relative to those formed with the basic alkaline peroxide chemical-mechanical refining (CMR) synergy. This reveals a great promise to EFB for application as super-strong fibre-web materials such as packaging and specialty paper-based products.
A Study on Commercial Polytetrafluoroethylene as a High Potential Polymer
Authors: Mukhtar N.Z.F. , Rusop Mohamad , Abdullah Saifollah
Published: November 2013

PTFE is a polymer of the type of Teflon. This polymer is from fluoropolymer family and made from monomer tetrafluoroethylene by polymerization. PTFE have properties that make them very useful in many application such as high melting point, extremely low friction of coefficient, very good chemical resistance, maximum mechanical resistance, non reactive polymer and good insulation properties. Therefore, this paper will report the study on commercial PTFE as an excellent remarkable polymer. The characterization will take over to analysis this polymer, respectively via Field Emission Scanning Electron Microscopy (FESEM), Fourier Transform Infra - Red Spectroscopy (FTIR) and X-Ray Diffraction (XRD). It was found that PTFE have spherical shape like branches with crystalline phase.
The Properties of ITO/Arc-ZnO Passivating Layer for TCO Conducting Substrate Deposited by RF Magnetron Sputtering
Authors: Abdullah Mohd Hanapiah , Ismail Lyly Nyl , Mahmood Mohammad Rusop
Published: November 2013

Abstract. In this work, a thermally stable multilayered transparent conducting oxide (TCO) utilizing ZnO antireflective thin film (arc-ZnO) has been prepared by RF magnetron sputtering. The novel ITO/arc-ZnO conducting substrate with blocking layer capabilities has been designed using step-down interference coating structure based on double layer antireflection coating (DLAR). The XRD result revealed a mixed-oriented type of crystalline structure between ITO and ZnO with preferred [222] and [002] orientations, respectively. The antireflection behaviour of multilayer ITO/arc-ZnO is evidence with the presence of two maximum peaks overshoots at 440 nm and 750 nm range while eliminating approximately 92% reflectance, hence contributes to higher overall transmittance (≥ 87%) in the mid-wavelength region. The ITO/arc-ZnO blocking layers conserves the low resistivity of ITO at 5.71 x 10-4 Ω cm, even after oxidizing during air annealing process above 400 °C. These results demonstrate that the multilayered ITO/arc-ZnO with tailored refractive index substrate is a realistic approach for higher overall transmittance with good stability in electrical properties, prolonged with an added capability of suppressing back electron transfer that is foreseen suitable for dye sensitized solar cell application.
Physico-Chemical and Morphological Changes of Sayong Kaolinite Clay Treated with Sulphuric Acid for Enzyme Immobilization
Authors: Edama N.A. , Sulaiman A. , Ku Hamid K.H. , Muhd Rodhi M.N. , Musa Mohibah , Abd. Rahim S.N.
Published: November 2013

This study analyzed the effects of sulphuric acid (H2SO4) treatment on pysico-chemical properties and morphological changes of clay obtained from Sg. Sayong, Perak. The clay was ground and sieved to <150μm and treated with different concentrations of H2SO4. The treatment was completed by refluxing the clay with different concentration of H2SO4 (1M, 5M and 10M ) at 100 °C for 4 hours and followed by calcination at 500 °C for 1 hour. The physic-chemical properties and morphological changes of the untreated and treated clay were compared using Surface Area Analyser, X-Ray Diffraction (XRD), Field Emission Scanning Electron Micrograph (FESEM), X-Ray Diffraction (XRD) and Fourier Transformed Infrared Spectroscopy (FTIR). The results showed that acid treatment of 5M increased the surface area from 25 m2/g to 75 m2/g and the pore volume increased from 0.1518 cc/g to 0.3546 cc/g. The nanopore size of the clay decreased from 24.8 nm to 19.4 nm after treated with acid. This can be explained due to the elimination of the exchangeable cations and generation of microporosity. The results of XRF showed SiO2 increased from 58.34% to 74.52% and Al2O3 reduced from 34.6% to 18.31%. The mineral oxides such as Fe2O3, MgO, CaO, K2O and TiO2 also reduced. This concluded that H2SO4 treatment has led to significant removal of octahedral Al3+, Fe3+ cations and other impurities. In conclusion, this study showed the physico-chemical properties and morphology of Sayong clay were improved once treated with H2SO4 and therefore suggests better supporting material for enzyme immobilization.
The Effect of PMMA Layer to the UV Properties of ZnO/PMMA Nanocomposite
Authors: Aziz Aadila , Asib N.A.M. , Afaah A.N. , Mohamed R. , Rusop Mohamad , Khusaimi Zuraida
Published: November 2013

Preparation of ZnO/PMMA nanocomposite has been reported by using the solution-immersion method. These studies involve depositing poly (methyl methacrylate) (PMMA) layer by layer on glass substrate using the spin coating technique. Surface morphologies deposited layer of PMMA on glass substrate was characterized using Atomic Force Microscope (AFM) and an optical property of ZnO/PMMA nanocomposite was characterized using UV-Vis Spectrometer. For AFM result, the highest surface roughness 0.048 nm represent layer of platinum due to its function as a seeded-catalyst followed by 1 layer of PMMA show surface roughness 0.015 nm. 4 hours immersion time show highest absorption for 5 layer of deposited PMMA at 279.21 nm. While, for 6 hours show highest absorption for 1 layer and 3 layer of PMMA with overlapped each other at 278.54 nm.
Effect of Post Annealing Temperature on Surface Morphology and Photoluminescence Properties of ZnO Thin Film
Authors: Eswar Kevin Alvin , Husairi F.S. , Ab Aziz Azlinda , Rusop M. , Abdullah Saifollah
Published: November 2013

Zinc acetate as starting material along with diethanolamine as a stabilizer and isopropyl as a solvent were used in ZnO precursor preparation while p-type silicon was used as a substrate in this work. ZnO thin films were deposited on silicon wafer by spin coating deposition method. Samples were annealed at different temperature in range 500°C to 800°C. In other to study the surface morphology of thin film, Field Emission Scanning Microscopic (FESEM) was employed for every sample. It was found that, the thin films are composed by ZnO nanoparticles with size of about 18.3 nm to 32.95 nm. Topology of ZnO thin films was characterized by atomic force microscopy (AFM). In other to study the photoluminescence properties, 325 nm of xenon lamp was used as sources within range of 350 nm and 600 nm. It is found that two peaks are appears for the entire sample with the high intensity peak at 373 nm originated from the contribution of near band edge recombination from ZnO and low intensity at 573 nm was corresponding to ZnO defects.
Aligning CdS Quantum Dots in Apo-Ferritin Protein and PS-b-P2VP Organic Templates
Authors: Shamsudin S.A. , Hasegawa Hirokazu , Takenaka Mikihito , Kenji Saijo
Published: November 2013

Quantum dots (QDs) have a great potential to be applied as a biosensor to detect cancer cells because of their properties such as high photoluminescence, photo stability, narrow peak of luminescence, etc. However, cadmium sulphide (CdS) quantum dots are toxic and hydrophobic, making it impossible to be applied into biomaterials. A template is needed to make CdS QDs nontoxic and hydrophilic. The optical properties of these QDs are needed to be protected. To achieve this purpose, the template for CdS QDs has been designed by capping CdS QDs with apo-ferritin shells before aligning them onto cylindrical perpendicular PS-b-P2VP template, with the aim of locating CdS QDs appropriately in sequence. A host-guest system can be developed.
Growth of ZnO Nanosturctures on Porous Silicon in Different Concentration of Zn2+ Ion
Authors: Eswar Kevin Alvin , Husairi F.S. , Ab Aziz Azlinda , Rusop Mohamad , Abdullah Saifollah
Published: November 2013

In this work, zinc nitrate was used as starting materials while hexamethylenetetramine as stabilizier and deionized water as a solvent. Electrochemical etching method was employed to modify p-type silicon wafer surface in substrate preparation. ZnO nanostructures were simply deposited on substrate by sol-gel immersion method. Different molarities of precursor were prepared to study the effect of Zn2+ ion concentration in growth of ZnO nanostructures. Field Emission Scanning Electron Microscopic (FESEM) revealed that concentration of Zn2+ ion precursor influences the growth of ZnO nanostructures. ZnO nanoflower was formed in low molarity and becomes nanospherical composed by nanorods in high molarity. X-Ray diffraction (XRD) spectroscopy was employed to analyse the structural properties. The result was confirming the formation of hexagonal wurtzite of ZnO nanostructures. Besides, the growth of ZnO nanostructures was aligned to (002) towards higher molarity.
Nitrogen Doping of Amorphous Carbon by Aerosol-Assisted Chemical Vapor Deposition for Carbon-Based Solar Cell Applications
Authors: Fadzilah A.N. , Kamaruzaman Dayana , Siran Yosri M. , Rejab Syahril Anuar M. , Asis Ahmad Jaril , Tahirruddin Syawaluddin , Rusop Mahmood Mohamad
Published: November 2013

A novel self-prepared Aerosol-Assisted Chemical Vapor Deposition (AACVD) system was developed to deposit the amorphous carbon (a-C) thin films for the carbon-based solar cell applications. The nitrogen doping was applied towards the a-C thin films at deposition temperature of 600°C and 650°C. The samples gave the photoresponse characteristic for the electrical measurement by using the solar simulator system in under illumination condition. FESEM images signify the nanostructured sized a-C:N (<100nm) and EDX spectrum clarify the presence of N content in the N doped a-C. Solar cell efficiency was also obtained with the value of 0.001648% for 650°C and 0.000124% for 600°C when the a-C:N were deposited on p-Si substrate. The presence of the rectifying curves at the a-C:N/p-Si junction indicates the hetero-junction behavior between the p-n structure and thus proves the successful doping of N doped a-C using the AACVD technique.
Influence of Deposition Time on Amorphous Carbon Thin Films Performance with Aerosol-Assisted Chemical Vapor Deposition
Authors: Fadzilah A.N. , Kamaruzaman Dayana , Siran Yosri M. , Syahril Anuar M. Rejab , Asis Ahmad Jaril , Syawaluddin Tahirruddin , Mahmood Mohamad Rusop
Published: November 2013

Pure amorphous Carbon (a-C) thin films had been deposited by Aerosol-Assisted CVD (AACVD) onto glass substrate in Argon atmosphere. The camphor oil was chosen as the carbon precursor to prepare the a-C thin films with the deposition time of 15 minutes, 30 minutes, 45 minutes, 60 minutes and 75 minutes. The electrical, optical and structural properties of the deposited a-C were discussed by using the current-voltage solar simulator system, UV-Vis-Nir spectrophotometer and Raman spectroscope respectively. For the electrical characterization, the samples showed the photoresponse performance when being illuminated under AM 1.5 illuminations: 100 mW/cm2, 25°C. Transmittance value for the a-C thin films was also considered high ~80% and the structural analysis by using Raman spectroscope exhibit two main peaks known as the D-peak and G-peak which is typical for the a-C.
Different Surface Morphology of Annealed PVDF-TrFE Thin Films and the Effect on its Ferroelectric Properties
Authors: Mohd Wahid Mohamad Hafiz , Mohd Dahan Rozana , Sa'ad Siti Zaleha , Arshad Adillah Nurashikin , Sarip Muhamad Naiman , Zulkefle Habibah , Rusop Mohamad , Gan Wee Chen , Abd Majid Wan Haliza
Published: November 2013

The different morphology of 250 nm PVDF-TrFE (70:30 mol%) thin films were observed in relation to its ferroelectricity. The annealing temperatures were varied from solvent evaporation (Ts), Curies transition (Tc), up to melting temperature (Tm). It was found that the annealing process promoted the development of elongated crystallite structure also known as ferroelectric crystal, which significantly improved the ferroelectric properties of PVDF-TrFE (70:30 mol%) thin films. However, the presence of nanoscale separations on the thin film annealed over Tm (AN160) suggested high possibility of defects, and hence a reduction in ferroelectric properties of thin films.
Preparation and Characterization of Crosslinked Latex Nanoparticles by Differential Microemulsion Polymerization
Authors: Hassmoro N.F. , Rusop Mohamad , Abdullah Saifollah
Published: November 2013

The differential microemulsion polymerization was used to synthesize crosslinked latex nanoparticles. In this paper, 1, 3-butylene glycol dimethacrylate (1, 3-BGDMA) was used as a crosslinking agent respectively 0-6 weight% of monomer total. The polymerization was carried out using butyl methacrylate (BMA), butyl acrylate (BA) and methacrylic acid (MAA) as the monomer mixture. The thin film of latex nanoparticles were prepared by using spin coating method and have been dried at 100°C for 5 minutes. The amount of the crosslinking agent added in the polymerization was optimized and we found that the particle sizes fall in the range of 30-60 nm. Field Emission Scanning Electrons Microscope (FESEM) was demonstrated that the spherical image of uncrosslinked latex change to a wooden-like image when the crosslinking agent added in the polymerization.
Effect of Annealing Temperature on TiO2 Nanostructured Prepared by Sol-Gel Method
Authors: Maarof S.K.M. , Rusop Mohamad , Abdullah Saifollah
Published: November 2013

Titanium Dioxide, TiO2 is one of the potential semiconductor materials. TiO2 has much application such as for pigments, oxygen sensors, and photocatalyst. Recently, the researcher study on the other application and revealed that this material has a great potential to be use in nanocoating area. The objective of this paper is to produce TiO2 nanostructured prepared by sol-gel method. Sol-gel was carried out using tetra (IV) isopropoxide (TTIP), absolute ethanol, Acetic Acid Glacial (GAA), Triton-X-100 and deionized water and all the solution was mixing by continuous stirring and heating. After finished prepare the sol-gel, solution will be spin coated onto glass substrate and annealed with different temperature for 2 hours. The particles were analyzed using Raman Spectroscopy to observe the crystallographic phase, and the morphology was evaluated through Atomic Force Microscopy (AFM). As a result, TiO2 that annealed at 450°C shows the better nanostructured compared to other annealing temperature.
Keywords: Titanium Dioxide (TiO2); Sol-gel method ; Spin-coating ; Annealing process ; Raman spectroscopy
Thermo Gravimetric Analysis Study of PMMA/TiO2 Nanocomposites
Authors: Hafizah N.N. , Mamat Mohamad Hafiz , Abidin Mohd Hanafiah , Said Che Mohd Som , Rusop Mohamad
Published: November 2013

The polymer matrix of poly (metyl methacrylate) (PMMA) has been introduced with the titanium dioxide (TiO2) nanopowder to study the effects of the TiO2size on the properties of the nanocomposites. The particle size is playing an important role in determining the properties of the nanocomposite. The decrease the filler size has increase the thermal decomposition of the nanocomposites due to the higher amount of the filler between the polymer chains. The results of X-ray diffraction (XRD) and Energy Dispersive X-Ray Spectrometry (EDS) also were discussed in this paper.
The Effect of Time Ageing of Spray-Deposited on the Growth of CdSe Nanoparticles
Authors: Rosmani C.H. , Zainurul A.Z. , Rusop Mohamad , Abdullah S.
Published: November 2013

Cadmium Selenide (CdSe) was obtained by using spray-deposited method which is using the sodium selenosulfite as Se precursor and cadmium chloride (CdCI) as cadmium (Cd) precursor. Time for each spray-deposited was used as the main parameter to investigate the properties of CdSe nanoparticles. By using FESEM for surface morphology and X-ray Diffraction (XRD) studies reveal that the CdSe nanoparticles with cubic crystal structures. In this research, the effect of time of spray deposited was main parameter to know the CdSe properties. The set of time was set from 10 min until 50 min. From FESEM result the size of CdSe nanoparticles were in the range 60-70 nm and the crystalline was hexagonal from XRD result. By using Scherrer equation, the size of crystalline of CdSe nanoparticles was determined from XRD characterization, the size was 60-70 nm. The size of CdSe nanoparticles from FESEM images were 60-80nm.
Photoluminescence Spectra of ZnO Thin Film Composed Nanoparticles on Silicon and Porous Silicon
Authors: Eswar Kevin Alvin , Husairi F.S. , Ab Aziz Azlinda , Rusop Mohamad , Abdullah Saifollah
Published: November 2013

ZnO thin film was successfully deposited on different substrate by sol-gel spin coating. Zinc acetate dihydrates, diethanolamine and isopropyl were used as starting material, stabilizer and solvent respectively. Two different substrate used in this work are p-type silicon wafer and porous silicon. Porous silicon was prepared by electrochemical etching. In order to study the surface morphology, field emission scanning electron microscopy (FESEM) was employed. It is found that, ZnO thin film was composed by ZnO nanoparticles. The averages size ZnO nanoparticle is 23.5 nm on silicon and 17.76 nm on porous silicon. Based on Atomic Force Microscopy (AFM) topology analysis, surface of ZnO thin films on porous silicon was rougher compared to ZnO thin films on silicon due to substrate surface effect. Photoluminescence spectra shows two peaks are appear for ZnO thin film on silicon and three peaks are appear for ZnO thin film on porous silicon. PL spectra peaks of ZnO thin film on silicon are correspond to ZnO and ZnO native defects while peaks of PL spectra on porous silicon are corresponds to ZnO, ZnO native defects and porous silicon.
Fabrication of Nanostructure Based Biosensor for Biomolecules Detection
Authors: Ariffin Shahrul A.B. , Adam Tijjani , Hashim Uda , Faridah Sfaridah S. , Zamri Ishak , Uda Muhammad Nur Aiman
Published: November 2013

Lately, nanostructure based biosensor application has drawn a lot attention among fellow researchers because of speciality to detecting cell, tissue and even disease caused by viruses either from humans, animals or agricultures. The nanostructure based biosensoris a result of the changed nature of nanomaterial to draw biomolecules and other biological samples based.In order to do so, formation of nanostructure based biosensor such nanowire must through a couplecritical or important processes such as trimming technique which leading towards formation of nanostructure while surface modification process leading towards by changing material of nanostructure behaviour to become biosensor. All the important process will be elaborated in technique section. Lastly in the result section, form structure produced, structure measurement and its behaviour will be elaborated.
An Exact Solution to the Local Fractional Richards' Equation for Unsaturated Soils and Porous Fabrics
Authors: Li Zheng Biao , Yun Yin Shan , Luo Hong Ying
Published: November 2013

A local fractional Richards equation is derived by considering the soil as fractal porous media, and an exact solution is obtained by a generalized Boltzmann transform and the fractional complex transform. The new theory predicts that the volumetric water content depends on the ratio (distance)2a /(time), where a is the value of fractal dimensions of the porous soil, and its value is recommended for various soils.
An Adaptive Liver Segmentation Method Based on Graph Cut and Intensity Statistics
Authors: Sun Yong Xiong , Huang Li Ping , Liu Li Peng , Huang Qiu Yang
Published: November 2013

An intensity statistics based graph cut segmentation algorithm is proposed in this paper to improve the accuracy and adaptive capacity of liver segmentation. The proposed segmentation method consists of four steps as follows: First, combined with the Otsu algorithm and associated with a cropped liver image, we defined a gray interval as the livers intensity range. Second, the fuzzy c-means clustering algorithm was applied to compute the average intensity and the variance. Third, we establish the cost function with the statistic results. Finally, we employed the improved graph cut model to extract the liver parenchyma from a large cross-section liver image. Experimental results show that the proposed segmentation method is feasible for different liver images of different intensity statistics.
Stereo Reconstruction of Infrared Images Captured in Microwave Reactor
Authors: Zhang Yin Hui , Peng Jin Hui , He Zi Fen
Published: November 2013

During metallurgy and food processing it is always necessary for real-time detection of stereo temperature distribution in reaction cavity of microwave. We focus on the stereo reconstruction of temperature distribution of the microwave reaction chamber using real-time image data captured by infrared sensor during heating process. Due to the stereo depth of the scene in humans vision system is mapped through disparity, thus the key technology stereo reconsturction of temperature is to find the corresponding points in the image pair. We employ the block matching algorithm to search the correspondence by minimizing a cost function derived on a hierarchical tree structured pyramid probabilistic graph. The study result shows that in the back projection of the depth map, the walls, ceiling, and floor of the microwave reactor all appear mutually orthogonal, which illustrates that the stereo temperature field is well reconstructed.
Analysis and Synthesis of Uncertainty Singular Markov Switched Systems Based on the Sliding Mode Control
Authors: He Zhao Lan , Gao Zong Wei , Bai Jing Jie
Published: November 2013

In this paper, a class of singular Markov switched systems with mismatched norm-bounded uncertainties and external disturbances is considered. A sufficient condition guaranteeing the existence of linear switching surface is given based on the linear matrix inequality method (LMIs). It is shown that the sliding mode dynamic on the switching surface is stochastically stable and satisfies performance. A sliding mode controller is designed to guarantee that the system trajectory is convergent to the linear switching surface. A numerical example is given to illustrate the effectiveness of the proposed method.
Driving Posture Recognition by Joint Application of Motion History Image and Pyramid Histogram of Oriented Gradients
Authors: Yan Chao , Coenen Frans , Zhang Bai Ling
Published: November 2013

This paper presents a novel approach to vision-based driving posture recognition. A driving action dataset was prepared by a side-mounted camera looking at a driver's left profile. The driving actions, including operating the shift lever, talking on a cell phone, eating and smoking, are decomposed into a number of predefined action primitives, which include operation of the shift lever, interaction with the drivers head and interaction with the dashboard. A global grid-based representation for the action primitives was emphasized, which first generate the silhouette shape from the motion history image, followed by application of the Pyramid Histogram of Oriented Gradients (PHOG) for more discriminating characterization. The random forest (RF) classifier was then exploited to classify the action primitives. Comparisons with some other commonly applied classifiers, such as kNN, multiple layer perceptron (MLP) and support vector machine (SVM), were provided. Classification accuracy is over 95% for the RF classifier in holdout experiment on the four manually decomposed driving actions.
Pitch Detection Method Based on HHT
Authors: Wang Yao Qi , Wang Xiao Peng , Lei Tao
Published: November 2013

A new method of pitch detection is proposed based on Hilbert-Huang Transform (HHT). Firstly noisy speech signal is filtered by morphological filtering to remove the noise, and then HHT is employed to get Hilbert-Huang spectrum and to calculate instantaneous energy and its derivative. Distinguish the unvoiced and voiced using mutation of instantaneous energy and track pitch.
An Integrated Framework for Biological Data Visualization
Authors: Song Cheng Long , Zou Chen , Wang Wen Ke , Li Si Kun
Published: November 2013

In the field of bioinformatics visualization, integrating software and data in different levels is the development trend. This paper presents an integration framework for biomolecular structure and genome sequences visualization. The framework can effectively support the data and software interoperability of biomolecular structure / genome sequences visualization. Based on the framework, we developed an integrated visualization system, which provides some new comprehensive visualization functions. Preliminary trial showed that the framework has a good prospect in the research of bioinformatics.
Vanishing Point Detection Algorithm Based on Clustering Method
Authors: Wan Fang , Yang R.
Published: November 2013

Camera self-calibration is a key step in photo based reconstruction works. Vanishing point detection is a very important method in single photo based camera self-calibration. We research current vanishing point detection method and put forward a detection algorithm based on a new clustering idea: J-Linkage. First, we construct a similar concept space from straight lines from images by edge detection and segmentation method. Then, we cluster the similar concept space to decide several main directions. At last, we can easily estimate vanishing points from the clustered categories. Experiment prove that, the method has a high performance efficiency and with good accuracy.