IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Dielectric Constant of nano- CCTO / Epoxy CompositeIOSR Journals
Nanocrystalline multiphase CaCu3Ti4O12 (CCTO) was prepared using Ca(NO3)2.4H2O, Cu(NO3)2.3H2O, TiO2 and C2H2O4.2H2O. The X-Ray differection and SEM analysed of the prepared CCTO powder sintered at 900oC and 950oC. A homogeneous ceramics-polymer nanocomposites consisting of CCTO particles as fillers and epoxy polymer as matrix have been prepared using a casting process. The nanocomposites exhibit enhanced dielectric constant and dielectric loss. Dielectric properties of CCTO ceramics were characterized in a broad frequency range (100 Hz-1 MHz) and at a temperature ranged from 25 oC to 150 oC. As a result of increasing the content of CCTO, the dielectric constant and dielectric loss of composites are increased. The increase of dielectric loss at high frequencies is due to the relaxation process in the polymer matrix.
Material Removal Rate, Tool Wear Rate and Surface Roughness Analysis of EDM P...ijsrd.com
Electrical discharge machining (EDM) is one of the non-traditional machining processes, based on thermo electric energy between the work piece and an electrode. In this process, the material removal is occurred electro thermally by a series of successive discrete discharges between electrode and the work piece. The parametric analysis of the EDM process by using different electrode materials has been carried out. The Material Removal Rate (MRR), Tool Wear Rate (TWR) and Surface Roughness (SR) is measured and recorded for detailed analysis. Different electrode
Electrical Properties of Thermally Evaporated In40 Se60 Thin Filmsiosrjce
In40 Se60 thin films with different thicknesses (300,500, and 700nm) have been deposited by single
source vacuum thermal evaporation onto glass substrates at ambient temperature to study the effect of thickness
and on its structural morphology, and electrical properties. AFM study revealed that microstructure parameters
such as crystallite size, and roughness found to depend upon deposition conditions. The DC conductivity of the
vacuum evaporated In40 Se60thin films was measured in the temperature range (293-473)K and was found to
increase on order of magnitude with increase of thickness. The plot of conductivity with reciprocal temperature
suggests, there are two activation energies Ea1and Ea2 for In40 Se60 for all thicknesses which decreases with
increasing thickness .Hall effect measurement showed that low thickness In40 Se60 film exhibit p-type
conductance whereas the film exhibit n-type towards the higher thickness. The electric carrier concentration
and mobility show opposite dependence upon thickness.
International Journal of Engineering and Science Invention (IJESI)inventionjournals
International Journal of Engineering and Science Invention (IJESI) is an international journal intended for professionals and researchers in all fields of computer science and electronics. IJESI publishes research articles and reviews within the whole field Engineering Science and Technology, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online
Activated carbon monoliths (ACMs) with average pore diameters in the meso- and micropore regions were successfully produced from biomass material. ACM synthesis uses chemical activation with KOH and ZnCl2 activating agents. The carbon and activating agent mass ratios were 1:1, 1:3, 1:5 and 1:7. Both activating materials produced an ACM with an average pore diameter of 3.2 nm. The specific capacitance, specific surface area, energy and power were as high as 63 F/g, 650 m2/g, and 0.23 Wh/kg for KOH and 73 F/g, and 522 m2/g, and 19 W/kg for ZnCl2 activating agents, respectively. For comparison, we also studied the physical and electrochemical properties of ACM with an average pore size in the micropore range from the same raw material.
Dielectric properties of Ni-Al nano ferrites synthesized by citrate gel methodIJERA Editor
Ni–Al ferrite with composition of NiAlxFe2-xO4 (x=0.2, 0.4 0.6, and 0.8, ) were prepared by citrate gel method. The Dielectric Properties for all the samples were investigated at room temperature as a function of frequency. The Dielectric constant shows dispersion in the lower frequency region and remains almost constant at higher frequencies. The frequency dependence of dielectric loss tangent (tanδ) is found to be abnormal, giving a peak at certain frequency for mixed Ni-Al ferrites. A qualitative explanation is given for the composition and frequency dependence of the dielectric loss tangent.
Optical and surface properties of al doped ga2 o3 by elemental stack methodeSAT Journals
Abstract Al doped Ga2O3 thin film was prepared by stacking of Al thin film on Ga2O3 thin film using thermal evaporator. The doping process was carried out by post annealing process at three different temperatures. The absorbance spectra revealed the Al doping process and showed low absorbance at high annealing temperature. Scanning Electron Microscope images were the evidence of surface effect due to Al diffuses at high annealing temperature (> 400°C). Energy Dispersive Spectra showed the changes in the elemental composition of Al doped Ga2O3 thin film for various annealing temperature and revealed Al diffusion by observed low Al content at the surface of the doped Ga2O3 thin film. Keywords: Ga2O3, Al doping, Optical properties, Surface analysis
Dielectric Constant of nano- CCTO / Epoxy CompositeIOSR Journals
Nanocrystalline multiphase CaCu3Ti4O12 (CCTO) was prepared using Ca(NO3)2.4H2O, Cu(NO3)2.3H2O, TiO2 and C2H2O4.2H2O. The X-Ray differection and SEM analysed of the prepared CCTO powder sintered at 900oC and 950oC. A homogeneous ceramics-polymer nanocomposites consisting of CCTO particles as fillers and epoxy polymer as matrix have been prepared using a casting process. The nanocomposites exhibit enhanced dielectric constant and dielectric loss. Dielectric properties of CCTO ceramics were characterized in a broad frequency range (100 Hz-1 MHz) and at a temperature ranged from 25 oC to 150 oC. As a result of increasing the content of CCTO, the dielectric constant and dielectric loss of composites are increased. The increase of dielectric loss at high frequencies is due to the relaxation process in the polymer matrix.
Material Removal Rate, Tool Wear Rate and Surface Roughness Analysis of EDM P...ijsrd.com
Electrical discharge machining (EDM) is one of the non-traditional machining processes, based on thermo electric energy between the work piece and an electrode. In this process, the material removal is occurred electro thermally by a series of successive discrete discharges between electrode and the work piece. The parametric analysis of the EDM process by using different electrode materials has been carried out. The Material Removal Rate (MRR), Tool Wear Rate (TWR) and Surface Roughness (SR) is measured and recorded for detailed analysis. Different electrode
Electrical Properties of Thermally Evaporated In40 Se60 Thin Filmsiosrjce
In40 Se60 thin films with different thicknesses (300,500, and 700nm) have been deposited by single
source vacuum thermal evaporation onto glass substrates at ambient temperature to study the effect of thickness
and on its structural morphology, and electrical properties. AFM study revealed that microstructure parameters
such as crystallite size, and roughness found to depend upon deposition conditions. The DC conductivity of the
vacuum evaporated In40 Se60thin films was measured in the temperature range (293-473)K and was found to
increase on order of magnitude with increase of thickness. The plot of conductivity with reciprocal temperature
suggests, there are two activation energies Ea1and Ea2 for In40 Se60 for all thicknesses which decreases with
increasing thickness .Hall effect measurement showed that low thickness In40 Se60 film exhibit p-type
conductance whereas the film exhibit n-type towards the higher thickness. The electric carrier concentration
and mobility show opposite dependence upon thickness.
International Journal of Engineering and Science Invention (IJESI)inventionjournals
International Journal of Engineering and Science Invention (IJESI) is an international journal intended for professionals and researchers in all fields of computer science and electronics. IJESI publishes research articles and reviews within the whole field Engineering Science and Technology, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online
Activated carbon monoliths (ACMs) with average pore diameters in the meso- and micropore regions were successfully produced from biomass material. ACM synthesis uses chemical activation with KOH and ZnCl2 activating agents. The carbon and activating agent mass ratios were 1:1, 1:3, 1:5 and 1:7. Both activating materials produced an ACM with an average pore diameter of 3.2 nm. The specific capacitance, specific surface area, energy and power were as high as 63 F/g, 650 m2/g, and 0.23 Wh/kg for KOH and 73 F/g, and 522 m2/g, and 19 W/kg for ZnCl2 activating agents, respectively. For comparison, we also studied the physical and electrochemical properties of ACM with an average pore size in the micropore range from the same raw material.
Dielectric properties of Ni-Al nano ferrites synthesized by citrate gel methodIJERA Editor
Ni–Al ferrite with composition of NiAlxFe2-xO4 (x=0.2, 0.4 0.6, and 0.8, ) were prepared by citrate gel method. The Dielectric Properties for all the samples were investigated at room temperature as a function of frequency. The Dielectric constant shows dispersion in the lower frequency region and remains almost constant at higher frequencies. The frequency dependence of dielectric loss tangent (tanδ) is found to be abnormal, giving a peak at certain frequency for mixed Ni-Al ferrites. A qualitative explanation is given for the composition and frequency dependence of the dielectric loss tangent.
Optical and surface properties of al doped ga2 o3 by elemental stack methodeSAT Journals
Abstract Al doped Ga2O3 thin film was prepared by stacking of Al thin film on Ga2O3 thin film using thermal evaporator. The doping process was carried out by post annealing process at three different temperatures. The absorbance spectra revealed the Al doping process and showed low absorbance at high annealing temperature. Scanning Electron Microscope images were the evidence of surface effect due to Al diffuses at high annealing temperature (> 400°C). Energy Dispersive Spectra showed the changes in the elemental composition of Al doped Ga2O3 thin film for various annealing temperature and revealed Al diffusion by observed low Al content at the surface of the doped Ga2O3 thin film. Keywords: Ga2O3, Al doping, Optical properties, Surface analysis
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
INVESTIGATION OF OPTIMIZED PROCESS PARAMETERS ON DENSIFICATION OF SAMARIUM CO...ijeljournal
The aim of this study is to investigate the effect of different process parameters on densification of
Samarium Cobalt 1:5 series (SmCo5) magnet by powder metallurgy technique. Different parameters for
sintering and heat treatment process such as particle size, load of press, sintering time and temperature,
furnace atmosphere and heating rate were tested in order to achieve the highest density. To analyze and
evaluate the microstructure and particle size of manufactured magnets scanning electron microscopy
(SEM) and X-ray diffraction (XRD) tests were conducted. Results of different tests showed that sintering
temperature as well as furnace atmosphere is among the most important parameters affecting on final
density of the samples. Investigations illustrated that highest density could be obtained with the sintering
of green bodies which made from initial particles with the size of 3 to 6 µm in vacuum condition at 1135˚C
for 30 min by rapid heating at the shortest time.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Effect of Separator Thickness and Preheating Temperature on the Development o...CrimsonPublishersRDMS
Effect of Separator Thickness and Preheating Temperature on the Development of Microwave Processed Composite Clads by Sarbjeet Kaushal* in Crimson Publishers: Peer Reviewed Material Science Journals
Comparative study on ammonia sensing properties of sno2 nanocomposites fabric...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Growth and Magnetic properties of MnGeP2 thin filmsinventy
We have successfully grown MnGeP2 thin films on GaAs (100) substrate. A ferromagnetic transition near 320 K has been observed by temperature dependent magnetization and resistance measurements. Field dependent magnetization experiments have shown that the coercive fields at 5, 250, and 300 K are 3870, 1380 and 155 Oe, respectively. Magnetoresistance and Hall measurements have displayed that hole conduction is dominant in MnGeP2. PACS: 75.50.Pp, 75.70.-i, 85.70.-w, 73.50.-h
Electrical properties of Ni0.4Mg0.6Fe2O4 ferritesIJERA Editor
Ni0.4Mg0.6Fe2O4 Ceramic samples were prepared by conventional double sintering approach and sintered at 1300oC/4 h. These ferrites are further characterized using X-ray diffractometer. The diffraction study reveals that the present compound shows perfect single phase cubic spinel structure. In addition, the behavior of distinct electrical properties such as dielectric constant (ε'), dielectric loss (ε") and ac-conductivity (ζac) as a function frequency as well as temperature is analyzed using the LCR controller.
Investigation of Optimized Process Parameters on Densification of Samarium Co...ijeljournal
Samarium Cobalt 2:17 series (Sm2Co17) magnet is prepared by powder metallurgy technique. Different parameters for sintering and heat treatment process such as sintering time, temperature, furnace atmosphere and heating rate were tested in order to achieve the highest density for Samarium Cobalt 2:17 series that could be obtained. To analyze and evaluate the microstructure and particle size of fabricated magnets, scanning electron microscopy (SEM) and X-ray diffraction (XRD) tests were used. Results show that sintering temperatures and furnace atmosphere are among the most important parameters that affecting on the density of the samples and consequently the magnetic properties. It is showed that the highest density of 7.98 g/cm3 (%95 of theoretical density) has been obtained from initial particles with the size of 3 to 6 µm and sintering temperature of 11950C with a rate of 17˚C/min for 1 hr in vacuum condition.
Investigation of Optimized Process Parameters on Densification of Samarium Co...ijeljournal
Samarium Cobalt 2:17 series (Sm2Co17) magnet is prepared by powder metallurgy technique. Different
parameters for sintering and heat treatment process such as sintering time, temperature, furnace
atmosphere and heating rate were tested in order to achieve the highest density for Samarium Cobalt 2:17
series that could be obtained. To analyze and evaluate the microstructure and particle size of fabricated magnets, scanning electron microscopy (SEM) and X-ray diffraction (XRD) tests were used. Results show that sintering temperatures and furnace atmosphere are among the most important parameters that affecting on the density of the samples and consequently the magnetic properties. It is showed that the
highest density of 7.98 g/cm3 (%95 of theoretical density) has been obtained from initial particles with the size of 3 to 6 µm and sintering temperature of 11950C with a rate of 17˚C/min for 1 hr in vacuum condition.
Investigation of Optimized Process Parameters on Densification of Samarium Co...ijeljournal
Samarium Cobalt 2:17 series (Sm2Co17) magnet is prepared by powder metallurgy technique. Different parameters for sintering and heat treatment process such as sintering time, temperature, furnace atmosphere and heating rate were tested in order to achieve the highest density for Samarium Cobalt 2:17 series that could be obtained. To analyze and evaluate the microstructure and particle size of fabricated magnets, scanning electron microscopy (SEM) and X-ray diffraction (XRD) tests were used. Results show that sintering temperatures and furnace atmosphere are among the most important parameters that affecting on the density of the samples and consequently the magnetic properties. It is showed that the highest density of 7.98 g/cm3 (%95 of theoretical density) has been obtained from initial particles with the size of 3 to 6 µm and sintering temperature of 11950C with a rate of 17˚C/min for 1 hr in vacuum condition
INVESTIGATION OF OPTIMIZED PROCESS PARAMETERS ON DENSIFICATION OF SAMARIUM CO...ijeljournal
Samarium Cobalt 2:17 series (Sm2Co17) magnet is prepared by powder metallurgy technique. Different parameters for sintering and heat treatment process such as sintering time, temperature, furnace atmosphere and heating rate were tested in order to achieve the highest density for Samarium Cobalt 2:17 series that could be obtained. To analyze and evaluate the microstructure and particle size of fabricated magnets, scanning electron microscopy (SEM) and X-ray diffraction (XRD) tests were used. Results show that sintering temperatures and furnace atmosphere are among the most important parameters that affecting on the density of the samples and consequently the magnetic properties. It is showed that the highest density of 7.98 g/cm3 (%95 of theoretical density) has been obtained from initial particles with the size of 3 to 6 µm and sintering temperature of 11950C with a rate of 17˚C/min for 1 hr in vacuum condition.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Microstructural and electrical study of eSAT Journals
Abstract Ceramics of (Ba0.6Sr0.4)(Zr1-xTix)O3 (x=0.40,0.50) samples were prepared by solid state reaction method. Micro structural study was performed by scanning electron microscope revealed the particle sizes are in the range of 0.8 μm. The structures are irregular in shape. Dc resistivity property was studied with respect to temperature from room temperature to 673 K. temperature of maximum resistivity (Tmax) are around 443 K and 378 K. dc dielectric constant, ac dielectric constant and dielectric loss were studied with respect to temperature from room temperature to 673 K at 100 Hz frequency. At higher temperature the dielectric constant of BSZT40 and BSZT50 is high. In the low frequency range dissipation factor is determined by the influence of ion conductivity. Index Terms: Ceramics, Barium Zirconate, Microstructure, DC Resistivity, Dielectric Constant and Dielectric loss
Dielectric behaviour of Ni+2 substituted Cu Co Nanocrystalline Spinel Ferrite...inventionjournals
Herein, the dielectric properties such as permittivity (real part ε’ and imaginary part ε”) and dielectric loss tangent (tan δ) are reported for the series [Nix Cu(constant) Co0.8-x Fe2O4] where constant=0.2 with x=0.2, 0.4 and 0.6 of ferrites, prepared by Sol-Gel auto-combustion technique by using high purity metal nitrate and citric acid as a catalyst. The variation in the real part (ε’) of dielectric constant , imaginary part ( ε”) of dielectric constant and dielectric loss tangent (tan δ) are studied at room temperature in the frequency range of 100 Hz to 5 MHz. Structural characterization of the annealed samples was done with the help of X-ray diffraction method. The particle size and single phase formation of NiCuCoFe2O4 ferrite was confirmed by Xray diffraction analysis and TEM. The particle size of prepared sample was confirmed by Scherer’s formula. The effect on Particle size (t) and lattice constant (Å) is observed due to substitution of Ni2+ in Cu Co. The digital LCR meter is used to obtain the magnetic properties of prepared pallets. The variations in the structural and dielectric properties of the prepared ferrite material are discussed
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Efficient distributed detection of node replication attacks in mobile sensor ...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
INVESTIGATION OF OPTIMIZED PROCESS PARAMETERS ON DENSIFICATION OF SAMARIUM CO...ijeljournal
The aim of this study is to investigate the effect of different process parameters on densification of
Samarium Cobalt 1:5 series (SmCo5) magnet by powder metallurgy technique. Different parameters for
sintering and heat treatment process such as particle size, load of press, sintering time and temperature,
furnace atmosphere and heating rate were tested in order to achieve the highest density. To analyze and
evaluate the microstructure and particle size of manufactured magnets scanning electron microscopy
(SEM) and X-ray diffraction (XRD) tests were conducted. Results of different tests showed that sintering
temperature as well as furnace atmosphere is among the most important parameters affecting on final
density of the samples. Investigations illustrated that highest density could be obtained with the sintering
of green bodies which made from initial particles with the size of 3 to 6 µm in vacuum condition at 1135˚C
for 30 min by rapid heating at the shortest time.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Effect of Separator Thickness and Preheating Temperature on the Development o...CrimsonPublishersRDMS
Effect of Separator Thickness and Preheating Temperature on the Development of Microwave Processed Composite Clads by Sarbjeet Kaushal* in Crimson Publishers: Peer Reviewed Material Science Journals
Comparative study on ammonia sensing properties of sno2 nanocomposites fabric...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Growth and Magnetic properties of MnGeP2 thin filmsinventy
We have successfully grown MnGeP2 thin films on GaAs (100) substrate. A ferromagnetic transition near 320 K has been observed by temperature dependent magnetization and resistance measurements. Field dependent magnetization experiments have shown that the coercive fields at 5, 250, and 300 K are 3870, 1380 and 155 Oe, respectively. Magnetoresistance and Hall measurements have displayed that hole conduction is dominant in MnGeP2. PACS: 75.50.Pp, 75.70.-i, 85.70.-w, 73.50.-h
Electrical properties of Ni0.4Mg0.6Fe2O4 ferritesIJERA Editor
Ni0.4Mg0.6Fe2O4 Ceramic samples were prepared by conventional double sintering approach and sintered at 1300oC/4 h. These ferrites are further characterized using X-ray diffractometer. The diffraction study reveals that the present compound shows perfect single phase cubic spinel structure. In addition, the behavior of distinct electrical properties such as dielectric constant (ε'), dielectric loss (ε") and ac-conductivity (ζac) as a function frequency as well as temperature is analyzed using the LCR controller.
Investigation of Optimized Process Parameters on Densification of Samarium Co...ijeljournal
Samarium Cobalt 2:17 series (Sm2Co17) magnet is prepared by powder metallurgy technique. Different parameters for sintering and heat treatment process such as sintering time, temperature, furnace atmosphere and heating rate were tested in order to achieve the highest density for Samarium Cobalt 2:17 series that could be obtained. To analyze and evaluate the microstructure and particle size of fabricated magnets, scanning electron microscopy (SEM) and X-ray diffraction (XRD) tests were used. Results show that sintering temperatures and furnace atmosphere are among the most important parameters that affecting on the density of the samples and consequently the magnetic properties. It is showed that the highest density of 7.98 g/cm3 (%95 of theoretical density) has been obtained from initial particles with the size of 3 to 6 µm and sintering temperature of 11950C with a rate of 17˚C/min for 1 hr in vacuum condition.
Investigation of Optimized Process Parameters on Densification of Samarium Co...ijeljournal
Samarium Cobalt 2:17 series (Sm2Co17) magnet is prepared by powder metallurgy technique. Different
parameters for sintering and heat treatment process such as sintering time, temperature, furnace
atmosphere and heating rate were tested in order to achieve the highest density for Samarium Cobalt 2:17
series that could be obtained. To analyze and evaluate the microstructure and particle size of fabricated magnets, scanning electron microscopy (SEM) and X-ray diffraction (XRD) tests were used. Results show that sintering temperatures and furnace atmosphere are among the most important parameters that affecting on the density of the samples and consequently the magnetic properties. It is showed that the
highest density of 7.98 g/cm3 (%95 of theoretical density) has been obtained from initial particles with the size of 3 to 6 µm and sintering temperature of 11950C with a rate of 17˚C/min for 1 hr in vacuum condition.
Investigation of Optimized Process Parameters on Densification of Samarium Co...ijeljournal
Samarium Cobalt 2:17 series (Sm2Co17) magnet is prepared by powder metallurgy technique. Different parameters for sintering and heat treatment process such as sintering time, temperature, furnace atmosphere and heating rate were tested in order to achieve the highest density for Samarium Cobalt 2:17 series that could be obtained. To analyze and evaluate the microstructure and particle size of fabricated magnets, scanning electron microscopy (SEM) and X-ray diffraction (XRD) tests were used. Results show that sintering temperatures and furnace atmosphere are among the most important parameters that affecting on the density of the samples and consequently the magnetic properties. It is showed that the highest density of 7.98 g/cm3 (%95 of theoretical density) has been obtained from initial particles with the size of 3 to 6 µm and sintering temperature of 11950C with a rate of 17˚C/min for 1 hr in vacuum condition
INVESTIGATION OF OPTIMIZED PROCESS PARAMETERS ON DENSIFICATION OF SAMARIUM CO...ijeljournal
Samarium Cobalt 2:17 series (Sm2Co17) magnet is prepared by powder metallurgy technique. Different parameters for sintering and heat treatment process such as sintering time, temperature, furnace atmosphere and heating rate were tested in order to achieve the highest density for Samarium Cobalt 2:17 series that could be obtained. To analyze and evaluate the microstructure and particle size of fabricated magnets, scanning electron microscopy (SEM) and X-ray diffraction (XRD) tests were used. Results show that sintering temperatures and furnace atmosphere are among the most important parameters that affecting on the density of the samples and consequently the magnetic properties. It is showed that the highest density of 7.98 g/cm3 (%95 of theoretical density) has been obtained from initial particles with the size of 3 to 6 µm and sintering temperature of 11950C with a rate of 17˚C/min for 1 hr in vacuum condition.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Microstructural and electrical study of eSAT Journals
Abstract Ceramics of (Ba0.6Sr0.4)(Zr1-xTix)O3 (x=0.40,0.50) samples were prepared by solid state reaction method. Micro structural study was performed by scanning electron microscope revealed the particle sizes are in the range of 0.8 μm. The structures are irregular in shape. Dc resistivity property was studied with respect to temperature from room temperature to 673 K. temperature of maximum resistivity (Tmax) are around 443 K and 378 K. dc dielectric constant, ac dielectric constant and dielectric loss were studied with respect to temperature from room temperature to 673 K at 100 Hz frequency. At higher temperature the dielectric constant of BSZT40 and BSZT50 is high. In the low frequency range dissipation factor is determined by the influence of ion conductivity. Index Terms: Ceramics, Barium Zirconate, Microstructure, DC Resistivity, Dielectric Constant and Dielectric loss
Dielectric behaviour of Ni+2 substituted Cu Co Nanocrystalline Spinel Ferrite...inventionjournals
Herein, the dielectric properties such as permittivity (real part ε’ and imaginary part ε”) and dielectric loss tangent (tan δ) are reported for the series [Nix Cu(constant) Co0.8-x Fe2O4] where constant=0.2 with x=0.2, 0.4 and 0.6 of ferrites, prepared by Sol-Gel auto-combustion technique by using high purity metal nitrate and citric acid as a catalyst. The variation in the real part (ε’) of dielectric constant , imaginary part ( ε”) of dielectric constant and dielectric loss tangent (tan δ) are studied at room temperature in the frequency range of 100 Hz to 5 MHz. Structural characterization of the annealed samples was done with the help of X-ray diffraction method. The particle size and single phase formation of NiCuCoFe2O4 ferrite was confirmed by Xray diffraction analysis and TEM. The particle size of prepared sample was confirmed by Scherer’s formula. The effect on Particle size (t) and lattice constant (Å) is observed due to substitution of Ni2+ in Cu Co. The digital LCR meter is used to obtain the magnetic properties of prepared pallets. The variations in the structural and dielectric properties of the prepared ferrite material are discussed
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Efficient distributed detection of node replication attacks in mobile sensor ...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Study on shear strength characteristics of coir mat reinforced sandeSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
An effective attack preventing routing approach in speed network in manetseSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Production of lactic acid from sweet meat industry waste by lactobacillus del...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Automatic power generation control structure for smart electrical power gridseSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
A comparative study of secure search protocols in pay as-you-go cloudseSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Studies on in-Doped Zno Transparent Conducting thin FilmsIJRESJOURNAL
ABSTRACT: In this manuscript we have investigated the influences of indium dopants on zinc oxide (ZnO) thin films regarding physico-chemical properties for application in modern conducting devices. As a starting material, Indium (III) chloride, and Zn(CH3COO)2⋅2H2O were used. The complex TSDC spectrum was obtained by submitting the sample to a constant electrical field Ep = 10M V/m during 2 min at a varing polarization temperature of Tmax = 1500C. A minimal sheet resistance with electrical resistivity as low in the range of 10-3 Ω·cm was found for this thin film.
A Study on Thermal behavior of Nano film as thermal interface layerIJASCSE
Increase in thermal design power and re-duce in manufacturing cost of the processor chip has pushes the need for high performance and durable test fixture design in future. Test fixture with efficient themal management has lowest resistance possible to maintain the accuracy of the device temperature when it makes contact with processor chip’s silicon during test. High thermal conductivity and mechanical relia-bility of text fixures are desired for high volume test environment. Nano film materials such as Aluminum Titanium Nitride (AlTiN), Titanium carbide (TiC), Ti-tanium on Titanium nitride (Ti on TiN), Titanium ni-tride on Titanium (TiN on Ti) and Aluminum(III) Ox-ide (Al2O3) are coated over copper substrates by Fil-tered Cathodic Vacuum Arc (FCVA) deposition method and tested for their thermal conductivity behavior for high volume test (HVM) environment. Thermal con-ductivity of the prepared films is tested by using the ASTM 5470 Thermal Interface Material (TIM) Tester. Titanium on Titanium nitride (Ti on TiN) and Alumi-num (III) Oxide (Al2O3) observed with highest thermal conductivity of 117.68 W/mk and 128.34 W/mk respec-tively among the prepared nano thin films. Thickness of the film and stack configuration influenced the thermal conductivity of the prepared film.
Evaluation Performance ofan Annular Composite Fin by UsingMATLAB ProgrammingIJERA Editor
The aim of this project is analysis the efficiency ratio in an annular fin by the variation of heat transfer coefficient for any surface condition by using MATLAB software to calculate the base fin efficiency and the coated fin efficiency by the variation of heat transfer coefficient, radius ratio and base fin thickness of an annular fin and compare the coating fin efficiency to base fin efficiency. If the heat transfer coefficient is 50W/m2K the increase efficiency ratio is 10.46 – 28.02% for zinc coating fin from the literature but the MATLAB result is 9.3 - 25.54% , the gain efficiency ratio at thicker base fin (d=0.001m) is 11.72%, at the thinner base fin (d=0.0002m) is 33.57% from the literature but the MATLAB result is 7.45% (d=0.001m) and 32.14% (d=0.0002m) for zinc coating fin and the gain efficiency ratio at thicker base fin (d=0.001m) is 11.92%, at the thinner base fin (d=0.0002m) is 33.61% from the literature but the MATLAB result is 7.51% (d=0.001m) and 32.16% (d=0.0002m) for zinc alloy coating fin.
Vanadium doped zinc telluride (ZnTe:V) thin films (containing 2.5 to 10wt% V) were deposited onto glass
substrates by e-beam evaporation technique in vacuum at a pressure of 8×10-4
Pa. Thermoelectric power of these
films have been measured from room temperature up to 413 K with reference to pure copper material. The
deposition rate of the films was maintained at 2.05 nms-1
. The composition and temperature dependence
thermopower and its related parameters have been studied in detail for a particular thickness of 150 nm. The
Fermi levels were determined using a non-degenerate semiconducting model. The carrier scattering index,
activation energy and temperature coefficient of activation energy have all been obtained at different ranges of
compositions and temperatures. The results of thermopower of ZnTe:V thin films obey an activated conduction
mechanism and also suggest that the simultaneous bipolar conduction of both (n- and p-types) carriers (mixed
carriers) take place. All these samples are optically transparent and mixed crystalline in structure
Measurement of Dielectric Properties of Low-Density Polyethylene Nanocomposit...TELKOMNIKA JOURNAL
Recently, many studies have been conducted on the dielectric properties of Low-Density
Polyethylene (LDPE) nanocomposites and produced different results. However, the composition of LDPE
polymer and boron nitride (BN) as nanofiller has neither been well understood nor producing a convenient
result. Similarly, the dielectric spectroscopy measured at “sub–hertz” frequency has been of little interest
among researchers since it is often influenced by “conduction-like” effect. This research identified the
dielectric properties of LDPE nanocomposites filled with hexagonal boron nitride (h-BN) nanofillers by
using dielectric spectroscopy technique. The dielectric loss and relative permittivity for three different filler
concentrations were investigated under “sub-hertz” frequency ranges at room temperature. The cylindrical
electrode with guard ring configuration was used to conduct the experiment, in accordance to the ASTM
D150 standard. The results revealed that 5 wt% filled polymer has lower loss tangent and permittivity
compared to the unfilled polymer, due to the strong interaction between nano-particle and the polymer.
This strong interaction is believed to limit the movement of the polymer chain. The decrease in loss
tangent also indicates lower quasi-DC at low frequency. However, further increase in the filler loading has
recorded an increment in the value of permittivity and loss tangent. This higher effective permittivity is
mainly due to the influence of the filler permittivity
Detecting of NH3, CO2 polluted gases by using ZnO- In2O3 thin filmsijceronline
International Journal of Computational Engineering Research (IJCER) is dedicated to protecting personal information and will make every reasonable effort to handle collected information appropriately. All information collected, as well as related requests, will be handled as carefully and efficiently as possible in accordance with IJCER standards for integrity and objectivity.
Detecting of NH3, CO2 polluted gases by using ZnO- In2O3 thin filmsijceronline
International Journal of Computational Engineering Research (IJCER) is dedicated to protecting personal information and will make every reasonable effort to handle collected information appropriately. All information collected, as well as related requests, will be handled as carefully and efficiently as possible in accordance with IJCER standards for integrity and objectivity.
The Performance of a Cylindrical Microstrip Printed Antenna for TM10 Mode as...ijngnjournal
A temperature is one of the parameters that have a great effect on the performance of microstrip antennas for TM10 mode at 2.4 GHz frequency range. The effect of temperature on a resonance frequency, input impedance, voltage standing wave ratio, and return loss on the performance of a cylindrical microstrip printed antenna is studied in this paper. The effect of temperature on electric and magnetic fields are also studied. Three different substrate materials RT/duroid-5880 PTFE, K-6098 Teflon/Glass, and Epsilam-10 ceramic-filled Teflon are used for verifying the new model.
Morphological, structural and electrical properties of pentacene thin films g...journalBEEI
The physical and structural characteristics of pentacene thin films on indium tin oxide (ITO)-coated glass were studied. The pentacene films were deposited using the thermal evaporation method with deposition times of 20, 30, and 60 minutes. Field-emission scanning electron microscopy (FESEM) images revealed that film thickness increased with deposition time, with a bulk phase layer appearing at 60 minutes. The presence of the thin-film phase corresponding to 15.5 Å lattice spacing was demonstrated by X-ray diffraction (XRD) patterns in pentacene films with deposition times of 20 and 30 minutes. Meanwhile, with a deposition time of 60 minutes and a lattice spacing of 14.5 Å, the existence of the bulk phase was verified in the pentacene film. Atomic force microscopy (AFM) images of the crystallinity of the pentacene films revealed that the pentacene films deposited on ITO-coated glass exhibited the formation of similar islands with modular grains, results in a fine crystalline structure. From the current-voltage (I-V) and current density-voltage (J-V) characteristics, the pentacene films were ohmic and that current increased as the pentacene’s thickness decreased. Pentacene films deposited on an ITO-coated glass substrate showed potential in the development of broadband and narrowband optoelectronic devices on a transparent substrate.
OFET Preparation by Lithography and Thin Film Depositions ProcessTELKOMNIKA JOURNAL
The length of the channel OFET based thin film is determined during preparation takes place
using the technique of lithography and mask during the metal deposition process. The lithography
technique is the basic process steps in the manufacture of semiconductor devices. Lithography is the
process of moving geometric shapes mask pattern to a thin film of material that is sensitive to light. The
pattern of geometric shapes on a mask has specifications, as follows: long-distance source and drain
channels varied, i.e. 100 μm, the width of the source and drain are made permanent. Bottom contact
OFET structure has been created using a combination of lithography and thin film deposition processes.
the effect of nickel incorporation on some physical properties of epoxy resinINFOGAIN PUBLICATION
The J-E characteristics of samples of epoxy resins mixed with nickel powder in different concentrations have been tested and a log-log straight line behaviour in both the low- and high field regions is observed. Ni-concentration has significant influence on the calculated constants of the J-E relationship. The d.c. electrical resistivity (ρ) of the samples are measured from the room temperature up to about 400 K. The variation of ρ with T obeys the exponential relation of ordinary dielectrics in three temperature regions. The parameters characterizing the ρ -T dependence change considerably with Ni-concentration. Due to the existence of nickel in different concentration a "true" compensation effect is observed with three characteristic compensation temperatures. The mechanical hardness of the samples was investigated as a function of Ni-concentration.
Similar to Performance of high power light emitting diode for (20)
Overview of the fundamental roles in Hydropower generation and the components involved in wider Electrical Engineering.
This paper presents the design and construction of hydroelectric dams from the hydrologist’s survey of the valley before construction, all aspects and involved disciplines, fluid dynamics, structural engineering, generation and mains frequency regulation to the very transmission of power through the network in the United Kingdom.
Author: Robbie Edward Sayers
Collaborators and co editors: Charlie Sims and Connor Healey.
(C) 2024 Robbie E. Sayers
Industrial Training at Shahjalal Fertilizer Company Limited (SFCL)MdTanvirMahtab2
This presentation is about the working procedure of Shahjalal Fertilizer Company Limited (SFCL). A Govt. owned Company of Bangladesh Chemical Industries Corporation under Ministry of Industries.
Water scarcity is the lack of fresh water resources to meet the standard water demand. There are two type of water scarcity. One is physical. The other is economic water scarcity.
About
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Technical Specifications
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
Key Features
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface
• Compatible with MAFI CCR system
• Copatiable with IDM8000 CCR
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
Application
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Hybrid optimization of pumped hydro system and solar- Engr. Abdul-Azeez.pdffxintegritypublishin
Advancements in technology unveil a myriad of electrical and electronic breakthroughs geared towards efficiently harnessing limited resources to meet human energy demands. The optimization of hybrid solar PV panels and pumped hydro energy supply systems plays a pivotal role in utilizing natural resources effectively. This initiative not only benefits humanity but also fosters environmental sustainability. The study investigated the design optimization of these hybrid systems, focusing on understanding solar radiation patterns, identifying geographical influences on solar radiation, formulating a mathematical model for system optimization, and determining the optimal configuration of PV panels and pumped hydro storage. Through a comparative analysis approach and eight weeks of data collection, the study addressed key research questions related to solar radiation patterns and optimal system design. The findings highlighted regions with heightened solar radiation levels, showcasing substantial potential for power generation and emphasizing the system's efficiency. Optimizing system design significantly boosted power generation, promoted renewable energy utilization, and enhanced energy storage capacity. The study underscored the benefits of optimizing hybrid solar PV panels and pumped hydro energy supply systems for sustainable energy usage. Optimizing the design of solar PV panels and pumped hydro energy supply systems as examined across diverse climatic conditions in a developing country, not only enhances power generation but also improves the integration of renewable energy sources and boosts energy storage capacities, particularly beneficial for less economically prosperous regions. Additionally, the study provides valuable insights for advancing energy research in economically viable areas. Recommendations included conducting site-specific assessments, utilizing advanced modeling tools, implementing regular maintenance protocols, and enhancing communication among system components.
Final project report on grocery store management system..pdfKamal Acharya
In today’s fast-changing business environment, it’s extremely important to be able to respond to client needs in the most effective and timely manner. If your customers wish to see your business online and have instant access to your products or services.
Online Grocery Store is an e-commerce website, which retails various grocery products. This project allows viewing various products available enables registered users to purchase desired products instantly using Paytm, UPI payment processor (Instant Pay) and also can place order by using Cash on Delivery (Pay Later) option. This project provides an easy access to Administrators and Managers to view orders placed using Pay Later and Instant Pay options.
In order to develop an e-commerce website, a number of Technologies must be studied and understood. These include multi-tiered architecture, server and client-side scripting techniques, implementation technologies, programming language (such as PHP, HTML, CSS, JavaScript) and MySQL relational databases. This is a project with the objective to develop a basic website where a consumer is provided with a shopping cart website and also to know about the technologies used to develop such a website.
This document will discuss each of the underlying technologies to create and implement an e- commerce website.
CFD Simulation of By-pass Flow in a HRSG module by R&R Consult.pptxR&R Consult
CFD analysis is incredibly effective at solving mysteries and improving the performance of complex systems!
Here's a great example: At a large natural gas-fired power plant, where they use waste heat to generate steam and energy, they were puzzled that their boiler wasn't producing as much steam as expected.
R&R and Tetra Engineering Group Inc. were asked to solve the issue with reduced steam production.
An inspection had shown that a significant amount of hot flue gas was bypassing the boiler tubes, where the heat was supposed to be transferred.
R&R Consult conducted a CFD analysis, which revealed that 6.3% of the flue gas was bypassing the boiler tubes without transferring heat. The analysis also showed that the flue gas was instead being directed along the sides of the boiler and between the modules that were supposed to capture the heat. This was the cause of the reduced performance.
Based on our results, Tetra Engineering installed covering plates to reduce the bypass flow. This improved the boiler's performance and increased electricity production.
It is always satisfying when we can help solve complex challenges like this. Do your systems also need a check-up or optimization? Give us a call!
Work done in cooperation with James Malloy and David Moelling from Tetra Engineering.
More examples of our work https://www.r-r-consult.dk/en/cases-en/
NO1 Uk best vashikaran specialist in delhi vashikaran baba near me online vas...Amil Baba Dawood bangali
Contact with Dawood Bhai Just call on +92322-6382012 and we'll help you. We'll solve all your problems within 12 to 24 hours and with 101% guarantee and with astrology systematic. If you want to take any personal or professional advice then also you can call us on +92322-6382012 , ONLINE LOVE PROBLEM & Other all types of Daily Life Problem's.Then CALL or WHATSAPP us on +92322-6382012 and Get all these problems solutions here by Amil Baba DAWOOD BANGALI
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NO1 Uk best vashikaran specialist in delhi vashikaran baba near me online vas...
Performance of high power light emitting diode for
1. IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308
__________________________________________________________________________________________
Volume: 02 Issue: 10 | Oct-2013, Available @ http://www.ijret.org 113
PERFORMANCE OF HIGH POWER LIGHT EMITTING DIODE FOR
VARIOUS ZINC OXIDE FILM THICKNESS AS THERMAL INTERFACE
MATERIAL
Subramani Shanmugan1
, Devarajan Mutharasu2
, Haslan Abu Hassan3
1, 2, 3
Nano Optoelectronics Research Laboratory, School of Physics, Universiti Sains Malaysia (USM), Minden, Pulau
Pinang, 11800, Malaysia, shagan77in@yahoo.co.in
Abstract
Oxide ceramic materials have attractive features either as filler or substrate materials in electronic packaging. Consequently, ZnO
thin film for various thicknesses was prepared over Al substrates by RF sputtering and used as heat sink for high power LED. The
thermal transient curve of device under test (DUT) was recorded for five boundary conditions. Rise in junction temperature (TJ) was
measured and observed low value (54.4°C) for 200 nm ZnO thin films at 350 mA. The difference in junction temperature rise (ΔTJ)
was observed as 7.46 °C at 700 mA when compared to bare Al substrates. The total thermal resistance (Rth-tot) of the DUT was low for
200 nm ZnO thin film coated Al substrates. AFM images were used to evaluate the surface roughness factors and their influence on
thermal resistance. As expected, the surface roughness, grain size and peak-valley distance were strongly influenced the heat flow.
Index Terms: ZnO thin film, thermal interface material, LED, thermal resistance, surface roughness
----------------------------------------------------------------------***------------------------------------------------------------------------
1. INTRODUCTION
Surface irregularities play a controlling part in the behavior of
the interface and may create thermal contact resistance as a
result of air gaps occupied at irregular surface. This could be
avoided and achieved good thermal contact conductance by
means of filling the air gap using thermally conductive
materials. As predicted, in all cases, the thermal resistance
follows a straight line as a function of bond line thickness
(BLT). Thermal conductivity of the bulk material is well
determined by this method [1].
Nitride and oxide based materials have been suggested for
thermal interface materials and thermal paste (TP) type TIM
has been mostly used for all electronic packaging applications
for ease of use. Though they have been employed extensively
as dielectric materials in printed circuit board technology for
effective heat dissipation, the synthesis processes of these
nitride and oxide based ceramic coated substrates are a
significant drawback as these raw materials are costly [2].
Zinc oxide is a II–VI compound semiconductor with wide
band gap (~ 3:37 eV), by which it has been recognized as a
promising photonic material in the ultraviolet (UV) region.
ZnO is very abundant in nature, has high thermal and chemical
stability [3].
Xu et al., also reported that out of all the commercial thermal
interface materials studied, the ZnO filled silicone of Dow
Corning gives the highest thermal contact conductance [4].
ZnO is also considered as a promising candidate for GaN
epitaxy as substrate mainly due to the fact that the lattice
mismatch between GaN and ZnO is very small compared to
that with the most commonly used substrate, sapphire. The
convincing thermal conductivity (1-1.2W/mK) and low
thermal expansion coefficient of wurzite ZnO [5] increases the
avenues of this material to be engineered into interesting hints
at new electronic applications down the road. The surface
quality plays a crucial role on thermal contact resistance and
defines the thermal conductivity considerably. Surface
roughness (finish) is defined as the average deviation from the
mean surface height. In general for very low thermal
resistance, a surface finish in the range of 1.27–1.5 µm is
recommended [6].
A research demonstrated that the surface roughness between
0.4 µm and 1.63µm in the presence of TIM resulted in less
than a 2.5% difference in interface thermal resistance [7]. In
our knowledge, thin film has not been reported as thermal
interface material especially ZnO. We have also prepared AlN
thin film as thermal interface materials in another work [8]
and achieved good results in contact conductance. In another
study, two different thickness of ZnO were tested as thermal
interface material and achieved good results where the
influence of surface parameters has not been addressed [9].
Accurate measurement of bond line thickness is necessary in
order to achieve precise bond line thickness control. A
conventional bond line thickness measurement method is
cross-sectioning, which requires a cured die to be cut open
2. IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308
__________________________________________________________________________________________
Volume: 02 Issue: 10 | Oct-2013, Available @ http://www.ijret.org 114
along a line. Generally, a thin bond line is preferred over a
thick one, since the stress concentration at the corners of the
joint is lesser in a thinner bond line. Also, the air cavity
concentration is lesser in a thin bond line as compared to a
thick one. Consequently, three different thicknesses of ZnO
thin film are used as thermal interface material and the
influence of their thickness and surface parameters on the
thermal resistance of given LED are tested.
1.1 Theoretical Background
The device junction temperature in the test condition can be
determined by
JJJ TTT ∆+= 0 (1)
Where TJ0 = initial device junction temperature (ºC), ΔTJ =
change in junction temperature due to heater power
application (ºC). Static mode was applied using still air box
for all measurement, which applies heating power to the DUT
on a continuous basis while the TJ was monitored through
measurement of temperature-sensitive parameter. The thermal
contact conductance for joint between contacting solids is
defined as
(2)
Where T1 and T2 are the temperatures of the bounding surfaces
of the contact, and Q/A is the heat flow per unit area [10]. The
effective total thermal resistance at the interface between two
materials is a sum of the resistance due to the thermal
conductivity of the TIM and contact resistance between the
TIM and the two contacting surfaces (see fig.1). This is
generally expressed as [11].
Reffective = (BLT/kTIM A) +Rc1+Rc2 (3)
Where, BLT and kTIM are the bond line thickness and thermal
Conductivity of the interface material respectively and A is the
area. Rc1 and Rc2 are contact resistances of the TIM at the
boundary with the two surfaces and illustrated schematically
in Fig. 1a. In this study, the prepared thin film thickness is
considered as bond line thickness.
Fig-1 (a) Thermal interface material inserted between the two
contacting bodies where Rc1 and Rc2 are contact resistances of
the TIM at the boundary with the two surfaces and (b)
Schematic illustration of LED employed thermal paste or ZnO
thin film as thermal interface material
Fig2. Rise in junction temperature of 3W green LED for five
different boundary conditions measured at 350 and 700 mA.
2. EXPERIMENTAL WORK
2.1 ZnO Thin Film Synthesis
The synthesis of ZnO thin film has already been reported in
another work by the same author [9]. Briefly, ZnO (99.99%
purity) target was used in RF sputtering for ZnO thin film
coating on Al substrates (23 cm x 25 cm x 1.5 cm) which were
used as heat sink. High pure Ar (99.999%) was used as
sputtering gas. Initially, the chamber pressure was pumped
down to 8.5 x 10-6
mbar after loading the ultrasonically
cleaned substrates into the chamber. Pre-sputtering was
carried out to remove the surface oxidation of the target
without opening the source shutter. All coatings were made in
150W RF power at chamber pressure of 6.61 x 10-3
. The ZnO
thin film was prepared in three different film thicknesses (200,
600 and 1200 nm). The surface morphology of the prepared
ZnO thin film was also tested using atomic force spectroscopy
)2121 (
//
TTA
Q
TT
AQ
T
AQ
hc
−
=
−
=
∆
=
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Volume: 02 Issue: 10 | Oct-2013, Available @ http://www.ijret.org 115
(AFM) (model: ULTRA Objective, Surface Imaging Systems,
GmbH) in the non-contact mode.
2.2 Thermal Transient Analysis
The thermal performance of prepared ZnO thin film as
interface material was tested and thermal transient curve was
captured for the given LED based on the electrical test method
JEDEC JESD-51. The high power (3W green) LED package
attached with Metal Core Printed Circuit Board (MCPCB) was
fixed on bare Al substrate (without and with thermal paste)
and ZnO thin film (200, 600 and 1200 nm) coated Al
substrates (see fig.1b) and carried out the experiment using
Thermal Transient Tester (T3Ster) in still air box. For
comparison, the thermal behavior of given LED with thermal
paste condition was also tested where cooler master thermal
paste kit was used as thermal interface material. The thermal
transient analysis was carried out for the given LED at three
different currents 100 mA, 350mA and 700 mA at room
temperature. The current densities were calculated as 0.961
A/mm2
, 3.37 A/mm2
and 6.75 A/ mm2
respectively. After the
LED was forward biased for 900s, the transient cooling curve
of heat flow was captured for another 900s. To confirm the
repeatability/ reproducibility, the experiment was repeated for
3 times. The obtained cooling profile of the LED for uncoated
and different thicknesses of ZnO thin film coated Al substrates
was processed for structure functions using T3ster Master
Software.
Fig3. Differential structure function of 3W green LED for five
different boundary conditions recorded at (a) 100, (b) 350 and
(c) 700 mA
3. RESULTS AND DISCUSSION
3.1 Thermal Resistance Analysis
The transient cooling curve for all samples is recorded and the
observed raise in junction temperature is given in Fig. 2. Since
the ΔTJ for 100 mA, we didn’t discuss the results here. But a
noticeable decrease in TJ could be observed at and above 350
mA driving currents for ZnO thin film interface. It reveals that
the rise in TJ shows very low for 200 nm ZnO thin film coated
substrates and the ΔTJ between bare and 200 nm ZnO thin
film samples show low value (ΔTJ =7.46 °C at 700 mA) than
other thicknesses.
Table1: Total thermal resistance of 3W green LED at five
boundary conditions
Total Thermal resistance (K/W)
Boundary conditions 100 mA 350 mA 700 mA
LED/Al 55.43 54.90 53.31
LED/TP/Al 54.32 54.08 52.16
LED/ZnO(200nm)/Al 54.20 50.67 49.46
LED/ZnO(600nm)/Al 55.51 53.31 52.09
LED/ZnO(1200nm)/Al 55.86 51.96 50.62
Moreover, rise in TJ for both TP and 600 nm ZnO thin film
interfaces shows almost similar results for ≥350 mA. An
increase in TJ from 200 nm to 600 nm may be due to either
higher thermal resistance of ZnO or surface roughness
parameters at higher thickness. The cumulative structure
function of 3W green LED for five different boundary
conditions was recorded as given in Fig. 3. The Rth-tot of the
given LED was measured from the cumulative structure
function and the observed values are given in Table – 1. From
table -1, the results measured at 100 mA reveals the influence
of ZnO interface thickness on Rth-tot as increases with
thickness. It also shows high value for ZnO thickness ≥ 600
nm. It obeys the conditions of equation 3 where the Reffective
increases with BLT increases. The Rth-tot values measured at
driving current ≥ 350 mA shows the behavior of the thermal
conductivity of ZnO thin film with temperature generated as a
result of rise in junction temperature. It is attributed to the
efficient lateral heat spread of thick ZnO thin film (>600 nm)
than thin ZnO (200 nm) at high current density.
Table 1 exhibits that the observed Rth-tot is low (49.46 K/W)
for 200 nm ZnO coated at 700 mA than other boundary
conditions. It is also observed that the Rth-tot is low for ZnO
coated Al substrates compared with TP applied boundary
condition. In addition, a small increase in Rth-tot is noticed with
increase of ZnO thickness from 200 nm to 600 nm. This may
be due to the influence of thermal mismatch between Al
substrate and ZnO at increased temperature. The thermal
mismatch is directly proportional to coefficient of thermal
expansions (CTE) and temperature difference since Al have
high CTE (22.2 x 10-6
/ K) than ZnO (2.43 x 10-6
/K). At high
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Volume: 02 Issue: 10 | Oct-2013, Available @ http://www.ijret.org 116
current density, the temperature difference between Al and
ZnO is high as a result of high TJ and hence thermal mismatch
stress developed at high current density (≥350 mA). It is
evidently proved by observed the difference in Rth (∆Rth) was
low for 100 mA (1.31 K/W) than higher driving current (≥350
mA). It is also observed that 100 % increment in ∆Rth could be
noticed for high driving current for 600 nm ZnO thin film
coated samples. Normally, the thermal conductivity of
polycrystalline material is determined by the grain size and
microstructure effects, such as impurity and defect [12,13].
Fig4. Interface thermal resistance of 3W green LED for five
different boundary conditions measured at various driving
currents
Overall, 200 nm ZnO coated Al substrates shows low Rth-tot
values for all driving currents. It attributes the influence of
BLT on the thermal resistance of the interface material. In
order to study the thermal resistance of interface material, the
interface resistance is derived from the cumulative structure
function analysis (Fig. 3) and the observed interface
resistances for different thickness of ZnO at various driving
current are shown Fig. 4. It explains that the interface
resistance is low for 200 nm ZnO thin film than other
thicknesses. Fig.4 also reveals the influence of driving current
on the interface resistance and shows low values for all
boundary conditions measured at 700 mA. It clearly indicates
that the interface resistance value increase for the film
thickness increases from 200 to 600 nm. This may be due to
the influence of surface roughness parameters such as step
profile of the surface or peak valley distance range. A detailed
discussion on this surface roughness parameters are discussed
in the consecutive section.
Moreover, a small decrease in resistance could be observed for
TP applied boundary condition than bare Al substrate
condition. This may be due to the thermal conductivity of
interface material (air - 0.024 W/m.K and thermal paste - 0.8
W/m.C). A decrease in interface resistance of ZnO thin film is
attributed to low thermal conductivity of thermal paste than
ZnO interface (1-1.2W/mK) used in this study. During the
burning of LED at high driving current, the temperature of the
interface is increased which induces the thermal conductivity
and hence the resistance decreases. But the quality of the thin
film also influences the thermal conductivity. In our study, the
interface resistance is observed as high for thicker film (≥600
nm) than 200 nm. It may be due to the volume of micropore
increases with increase in thickness [14] and hence the
interface resistance increases.
3.2 Surface Analysis by AFM
In order to measure the surface topography, AFM was used to
capture the surface images of the bare Al and ZnO coated Al
substrates and presented in Fig. 5 (a-d). Fig. 5 a shows the
surface image of bare Al substrate and reveals the rough
nature and Fig. 5 (b-d) depicts the surface topography of ZnO
thin film coated Al substrates for various thickness and also
show smooth surface when compared to bare Al one. From
fig. 5, it is easy to understand that the film thickness plays an
important role on surface modification. Each fig. parts in Fig.5
have distinct surface which is mainly due to substrate and film
thickness variations.
Table2. Surface roughness parameters of ZnO thin film coated
on Al substrates
Samples Bare Al 200nm
ZnO/Al
600nm
ZnO/Al
1200nm
ZnO/Al
Roughness (nm) 34.2 5.3 13.5 11
Grain size (µm) 1.43 0.25 0.49 0.32
Peak – valley
range (nm)
200-500 25-55 60-145 35-125
Max. peak-
valley range
(nm)
320 40 100 80
It has been reported that roughness plays an important part in
determining the thermal resistance of a contact interface. The
influence is positive, i.e., increases the resistance. A twofold
increase in roughness can result in a four to fivefold increase
in the thermal resistance [15].
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Volume: 02 Issue: 10 | Oct-2013, Available @ http://www.ijret.org 117
Fig5. AFM images of (a) bare and ZnO thin film coated Al
substrates at (b) 200 nm, (c) 600 nm and (d) 1200 nm
thickness
Fig6. Step profile of (a) bare and ZnO thin film coated Al
substrates at (b) 200 nm, (c) 600 nm and (d) 1200 nm
thickness.
Consequently, the surface roughness of the all our samples are
also measured using software and the observed values are
presented in Table – 2. It clearly indicates that the roughness
value increases with thickness increases. Among the ZnO thin
film samples, low value in surface roughness could be
observed with 200 nm ZnO on Al and hence the LED samples
with 200 nm ZnO coated Al substrates show low value in Rth-
tot than other thicknesses. Moreover, thin film coating gives
surface smoothness when it is coated over rough or unpolished
surfaces and evidenced by observing low surface roughness
values than bare substrate (see fig.5). A noticeable increment
in surface roughness could be observed from 200 nm to 600
nm ZnO thin film samples. This could be one of the reasons
for huge difference in Rth-tot between 200 and 600 nm ZnO thin
film samples as stated by Yovanovich et al work [15].
Fig7. Peak-valley distance of (a) bare and ZnO thin film
coated Al substrates at (b) 200 nm, (c) 600 nm and (d) 1200
nm thickness
In addition, the grain size of ZnO thin film is also evaluated
from AFM images and also given in table – 2. It shows that
the grain size increases with thickness increases. According to
the ref. [13], the grain size is one of the leading factors which
affect the thermal transport which is evidently proved in our
studies by observing low Rth-tot and Rth-b-hs for 200 nm ZnO
thin film than other thickness. Moreover, the thermal contact
resistance of ZnO thin film with large grain size is high
compared to thin film with small grain size and hence the 200
nm ZnO thin film shows low resistance value than other
thickness [14]. It can be seen that the 200 nm ZnO thin film
show smaller grain size than other two thicknesses (600 and
1200 nm).
The surface step profile study is a scientific approach for the
surface analysis in electronic industries. It will give the
surface waviness profile of the specified surface under study.
It is the measure of the highest peak and deepest valley across
the surface profile from the baseline. It clearly represents the
contact points on the surface for thermal conductivity [16]. To
analyze the surface step profile of the bare and ZnO thin film
coated surface, the AFM images were processed using
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Volume: 02 Issue: 10 | Oct-2013, Available @ http://www.ijret.org 118
software and observed the surface step profile as given in Fig.
6. It also clearly indicates that the area under the curve
indicates the distribution of highest peak and deepest valley
across the bare Al and ZnO thin film surface. The X axis
shows the percentage of step profile distribution on the surface
and shows maximum height of the surface step profile for bare
Al substrate and the range is also between 200 and 500 nm.
Fig. 6 also clearly depicts that the peak height and depth
valley distribution is low for 200 nm ZnO coated Al substrates
than all other ZnO thicknesses (see table - 2).
From the AFM analysis, it could also be observed that the
roughness profile of the surface of bare and ZnO thin film
coated substrates are given in Fig. 7 (a-d). In order to
understand the increase of Rth-tot for 600 nm ZnO thin film
coated Al substrate in detail, the peak-valley distance analysis
is also carried out using the roughness profile of all bare and
ZnO thin film surfaces and the observed results are presented
in Table – 2. It clearly indicates that the maximum peak-valley
distance is high for 600 nm ZnO thin film (100 nm) than other
thicknesses and hence the contact conductance of MCPCB on
600 nm ZnO thin films coated Al substrate is low compared to
other thicknesses.
CONCLUSIONS
RF sputtered ZnO thin film was used as TIM for high power
LED and tested the thermal resistance of 3W green LED at
three different ZnO thicknesses. 200 nm ZnO thin film coated
Al substrates showed high ΔTJ vale of 7.46 °C at 700 mA
when compared with bare substrate. Low Rth-tot and TJ was
evidently proved due to low BLT (200 nm of ZnO thin film) at
interface between MCPCB and heat sink. In addition, heat
transport at high rate was also achieved with low surface
roughness of ZnO thin film with smaller particles.
REFERENCES
[1]. www.assemblyanswers.com/resources/.../TIM-
Resistance-Paper.pdf
[2]. Y. J. Heo, H. T. Kim, S. Nahm, Y. J. Yoon and Y. Kim,
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[3]. J. P. Mathewa, G. Varghese, and J. Mathew, Chin.
Phys. B 21, 078104 (2012)
[4]. Y. Xu, X. Luo and D. D. L. Chung, Transactions of the
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Steiner, Prog. Mater. Sci. 50, 293, (2005).
[6]. B. Roehr, “Mounting Considerations for Power
Semiconductors”, Motorola Application Note AN1040.
[7]. Catalog #87-HS-9, pp. 8, Thermalloy Inc., Dallas, TX,
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[8]. S.Shanmugan, D.Mutharasu and H. Abu Hassan, Int. J.
Electro. Comp. Sci. Engg., 2, 296, (2012)
[9]. D. Mutharasu, S. Shanmugan, P. Anithambigai, and O.
Zeng Yin, IEEE Trans. Elect. Devices, (In press)
[10]. L.S. Fletcher, IEEE Trans. Compon., Hybrids, Manuf.
Tech. 13, 1012, (1990).
[11]. D. Blazej, Electronics Cooling; 9, 14, (2003).
[12]. Y-d. Li, De-m. Wang, H. Jin, J-p. Lu, J. Zhou; Effect of
film thickness on properties of Al-doped ZnO film as
transparent conducting electrodes in OLEDs, 978-1-
4673-2475-5/12, IEEE proceedings.
[13]. J.Z. Tian, D.J. Yang, C.K. Chen, H. Cheng, P. Hing, J.
Appl. Phys. 96, 4563, (2004).
[14]. Z. X. Huang, Z.A. Tang, J. Yu, S. Bai, Physica B 406,
818 (2011)
[15]. M. M. Yovanovich, W. M. Rohsenow; Influence of
surface roughness and waviness upon thermal contact
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[16]. Application notes, InTech-
Measurement_of_the_nanoscale_roughness_by_atomic
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pdf
BIOGRAPHIES:
Shanmugan Subramani has received his
bachelor degree (1997) in chemistry,
diploma in (1998) chemical process
instrumentation and Master degree (2000)
in Energy Science. He has received his
Ph.D in the field of thin film solar cells
during 2009. He has published more than
65 research papers in the refereed
International journals and conferences. He also has a research
experience of more than 7 years. Now he is working as a Post
Doctoral Research Fellow in School of Physics, University
Sains Malaysia upto date. His research is focused on
identifying best thermal interface material in solid state
devises in semiconductor industries.
Mutharasu Devarajan holds a master’s
degree (1991) in Physics and M.Phil
(1992) & PhD (2000) in Energy Sciences
(Renewable energy) from Madurai
Kamaraj University, India. He has
received the young scientist fellowship
awards from Indian National Science
Academy (INSA) in 2001 and Tamilnadu
State Council for Science and Technology (TNSCST), India in
2002 as recognition to his research in the field of Alternative
energy – specialized in solar thermal and photovoltaic
technologies. He has published more than 140 research papers
in the refereed International journals and conferences. He has
a teaching and research experience of more than 20 years.
Currently, he is working as Associate Professor with school of
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Volume: 02 Issue: 10 | Oct-2013, Available @ http://www.ijret.org 119
physics, USM, Penang, Malaysia. His research interests
include heat transfer in semiconductors and materials
characterization.
Haslan Abu Hassan was born in Malacca,
Malaysia in 1960. He received the B.Sc.
degree in Physics from the University of
East Anglia, United Kingdom in 1983, and
the M.Sc. and Ph.D. degrees from the
University of Essex, United Kingdom in
1984 and 1987, respectively, for the study
of excitations in semiconductor
superlattices. He has been with the School
of Physics, Universiti Sains Malaysia, Penang, Malaysia, since
1987, and was the Dean of the School of Physics from 2005 to
2010. Professor ABU HASSAN is currently serving as the
Director of the Centre for Education and Training in
Renewable Energy, Energy Efficiency and Green Technology
(CETREE>), Universiti Sains Malaysia. His research
interests include thin films of III-V nitrides for laser diodes
and solar cells, nanowires of GaN as solar cells, surface
phonon polaritons from nitride interfaces and thermoelectric
materials from chalcogenides