Magnetic refrigerators have emerged as an important trend in the refrigeration industry. They are believed to be more efficient than current and popular cooling systems by approximately 50%. The underlying principles of magnetic refrigerators are the thermodynamics laws of changing in temperature associated with magnetization and demagnetization of a magnetic regenerator. A numerical model of...
In this work, Na-doped $WO_3$ nanorods were successfully synthesized by a precipitation method and significantly evaluated for gas-sensing detection. The as–prepared nanoparticles and their fabricated sensing films were structurally characterized by X-ray analysis, nitrogen adsorption, and electron microscopy. The results confirmed that the p-type Na-doped $WO_3$ nanorods were highly...
All glass samples in the system (90-x)RWG - 10Na$_2$O - xNd$_2$O$_3$ where the RWG is recycled window glass (where x = 0, 0.1, 0.25, 0.5, 0.75 and 1 in mol% respectively).The glass samples were prepared by using melt quenching method. The elastic moduli were studied by measurement ultrasonic velocities using pulse echo technique.The structural properties of the glass samples were investigated...
Recently, IrMn alloy were used as coupled layer with a ferromagnetic layer to increase sensitivity in magnetic sensing for magnetic data storage because this film can maintain high exchange bias strength even with ultra-thin layer. IrMn thin films were grown by magnetron sputtering technique. The films contained the face center cubic structure with Mn concentration in range of 65-80 wt.%....
Abstract
This research synthesized the mesoporous silica nanoparticles. TEOS is used as a precursor and two types of surfactant, CTAB and TTAB, to be used as structure directing agent. To compare the effect of template type on the characteristics of synthetic particles, molar ratio of precursor to template is equally controlled. The co-condensation combine with bi-phasic techniques are...
In this research, the study to investigate and compare the physical and mechanical properties of water hyacinth and cattail fiber reinforced epoxy hybrid composites.
The composites were fabricated by hand lay-up process. The effect of investigation was analyzed via density, moisture absorption, microstructure, tensile strength, flexural strength and impact strength tests for total fiber...
Magnetic refrigeration (MR) has been receiving an attention as an alternative system to conventional refrigeration based on vapor compression. Normally, the vapor compression uses hydrofluorocarbons (HFC) and Chlorofluorocarbons (CFC) as refrigerant fluids which damage ozone layers causing global warming. Consequently, the magnetic system has been developed to replace the traditional system to...
The aim of this work is to study the effect of banana fibers three species : Musa (ABB)(Kluai Nammwan: A1), Musa balbisiana Colla (Kluai Tanee: A2) and Musa (AAA) (Kluai Hom thong: A3) on physical and mechanical properties of banana fiber reinforced epoxy resin composites. The finding of experiment showed that addition of B1 and B2 improves tensile strength and impact strength respectively,...
In this study, we report the influence of textile substrates upon the behavior of electrical and gas sensing properties of polyaniline (PANi) coated on the commercially single yarn. The sensing devices were prepared by dip coating of PANi on various kinds of yarn structure including cotton, viscose rayon and polyester. Sensor fabrication parameters which included precursor, reagent and acidity...
Tanzanite is blue to violet gem variety of mineral zoisite. It is a very popular jewelry gemstone in gems trade. Due to the unique beautiful color of tanzanite is rarely natural; almost tanzanites are usually has been heat-treated to enhance the beautiful color. In this research, color enhancement of natural tanzanite from Tanzania was performed by heat treatment and its spectroscopic...
Carbon powder was prepared from bamboo shoots by chemical activation. The porous carbon powders were activated by potassium hydroxide (KOH) at 400, 500 and 600°C for 2 hrs under argon (Ar) atmosphere with carbon powder (C): KOH ratio of 1:1, 1:2, 1:3 and 1:4 by weight, respectively. The crystal structure, morphological properties and the porosity of carbonaceous powders were investigated by...
This work mentions a surface treatment of ZnO film by sulfuric acid solution. The ZnO film was prepared from commercial ZnO nanoparticles using screen printing method. The ZnO film was vertically dipped into diluted sulfuric acid solution for different treatment times. Morphology of the treated ZnO film shows small different change. The treated ZnO film was used as photoelectrode of...
Mixed halide perovskites MAPb(I+Br)3 (MA=CH3NH3) are strong candidates for thin-film solar cells, as they are solution processable with excellent photovoltaic properties. With both halide and dimensionality tuning, colored perovskites can be fabricated with potential application for semi-transparent solar cells. Typically, spin coating is utilized for perovskite formation. However, to enable...
Saowalak Homnan$^1$$^,$$^a$, Anurat Wisitsoraat$^2$$^,$$^3$$^,$$^b$, Adisorn Tuantranont$^2$$^,$$^4$$^,$$^c$, Sukon Phanichphant$^2$$^,$$^d$, Chaikarn Liewhiran$^1$$^,$$^2$$^,$$^5$$^*$
$^1$Department of Physics and Materials Science, Faculty of Science, Chiang Mai University,Chiang Mai 50200, Thailand
$^2$Center of Advanced Materials for Printed Electronics and Sensors, Materials Science...
Perovskite barium titanate (BaTiO3) ceramics are widely used in electronics industries such as capacitors, sensors and actuators. BaTiO3-based ceramics have good dielectric, ferroelectric and piezoelectric properties. BaTiO3 powder was fabricated by mixed-oxide method via a vibro-milling technique. The pellets were then placed in a high purity alumina crucible in air and sintered at 1375 °C...
In this project, we focus on fabrication and characterization of graphene-based heterostructures. First, we use “Pick-up method” at low transfer temperature (T = 40 - 60 oC) in order to fabricate the h-BN/graphene/h-BN van der Waals heterostructure on silicon oxide substrate. We find that transferring graphene at low temperature leaves hydrocarbon residues between graphehe/h-BN interface which...
The fabrication of supercapacitors electrode with carbon powders material synthesized different wood such as of Broken Bone tree wood, Rain Tree wood, Kapok wood, Bitter bush wood, macrophyllus wood, Copper pod wood, Black Siris wood and Iron wood. Carbon powders from physical activation were prepared at 1000 ºC for 2 hrs under flowing argon. The structural properties, morphological and...
Sugar is one of the most common ingredients in most of the food processing. Recently, the social healthy trend raises awareness on the sugar control in foods, leading to a demand on a fast and simple sugar sensor. Recently, a non-enzymatic glucose sensor has gained a lot attention, because it is re-useable, fast and simple, as opposed to traditional enzymatic glucose sensor. In this work,...
Nano-silica aerogels were synthesized from sodium silicate which is obtained from the reaction of bagasse ash and NaOH. Silanes and salazane was employed to control the formation and structure of silica aerogels in this study. To initiate the modification of silica aerogel properties, 1.0 M NH4OH solution was utilized. The silica aerogel resulted from the reaction was dried under ambient...
This research aims to prepare the polyvinylidene fluoride-hexafluoropropylene (P(VDF-HFP)) fibers by electrospinning process with different electric fields. The aluminium chloride hexahydrate (AlCl$_3$.6H$_2$O) was filled into the fibers to act as nucleating agent for $\beta$ phase transformation. The morphology and phase transformation of the neat fiber mats with and without AlCl$_3$.6H$_2$O...
This research aimed to study mechanical and physical properties of epoxy resin based hybrid composites reinforced with banana fiber three species; Musa X paradisiaca L. (Kluai TEEP: B1) Musa sapientum (Kluai Hin: B2) and Musa sapientum Linn. (Kluai Leb Mu Nang: B3). The mechanical properties of composites were evaluated tensile strength tensile modulus flexural strength flexural modulus and...
In this work, the usage of manganese (Mn) as an inexpensive alloying element for ferrous powder metallurgy was investigated. The mechanical properties of sintered Astaloy 85Mo and Astaloy CrM with different Mn and carbon (C) content were compared. Ferromanganese (FeMn) 1.25% and 2.5% and graphite 0.2%, 0.4%, and 0.6% by weight were mixed with Astaloy 85Mo and Astaloy CrM. The change of...
High chromium cast irons are widely used as abrasion resistant wear parts in mining, mineral and cement industries. Their abrasion and corrosion resistance can be improved by destabilisation heat treatment and element addition. Mo additions to high Cr irons lead to the formation of M2C or M6C type carbides depending on the Cr/C ratio. In the present work, iron containing 28 wt.%Cr-3 wt.%C-1...
Water pollution is a major problem that impact to the world environments. There are many methods to solve this problem such as physical, biological and chemical method. In chemistry, the researcher focuses to use the new photocatalyst to treat the water pollution. One of them, silver phosphate (Ag$_3$PO$_4$) has been attention because it has high photocatalytic activities. In this research...
Molecular dynamic and mesoscopic simulations are used to predict the morphologies of PS-b-PI diblock copolymer. Flory-Huggins interaction parameter is an intermediate parameter used to connect between both simulations. The repulsions between different beads are one of essential parameters that were calculated from the Flory-Huggins interaction parameter. The calculated repulsion is 3.79...
Following our interest in photoluminescence properties of lanthanide coordination polymers constructed using 2-nitro-1,4-benzenedicarboxylate (NO$_2$-BDC$^2$$^-$ [1,2], the lanthanum and its europium and terbium doped samples have been prepared; [(La)(NO$_2$-BDC)$_1$$_.$$_5$(H$_2$O)$_4$] (1),[(La$_0$$_.$$_9$$_2$Eu$_0$$_.$$_0$$_8$)(NO$_2$-BDC)$_3$(H$_2$O)$_4$] (2),...
CsI doped with Tl (CsI:Tl) is a scintillator material used for radiation detector applications. CsI:Tl was crystalized by a modified homemade Bridgman-Stockbarger technique using different precursor purities. The purpose is to verify effects of precursor purity on optical properties of Cs:Tl crystals by UV-VIS and X-ray luminescence spectroscopy. A concentration of impurities in the precursor...
Sintered Fe-Cr-Mo-Si-C alloys, produced from two different pre-alloyed powders with compositions of Fe-3.0Cr-0.5Mo and Fe-1.5Cr-0.2Mo, showed a microstructure similar to that of a fully pearlitic ductile cast iron (DCI EN GJS700-2). The two sintered alloys exhibited close values of area fractions of a black particle (7 % of area fraction for the sintered Fe-1.5Cr-0.2Mo-inherited alloy or...
The SrTiO$_3$ ceramics were fabricated by sol–gel and solid-state reaction hybrid method. The powders synthesized at the SG:SR molar ratio of 0.1:1 calcined at 950$^o$C for 2 hours were used to prepare the ceramics which were after sintered at 1050, 1150, 1250, and 1350$^o$C. The crystal structures, morphologies and dielectric properties of the ceramics were subsequently characterized. The...
In this research, the (Ba0.90Ca0.10)0.90(Na0.5Bi0.5)0.10TiO3 or BCT-NBT ceramics prepared by mixed oxide method with various sintering temperatures were investigated. The optimum calcination condition was found at 850oC for 4 h. These powders were pressed and sintered at 1000-1400oC for 3 h with a heating rate of 5oC/min. The microstructure was examined by scanning electron microscope (SEM)....
Self-assembly of magnetic nanoparticles into a long-range monolayer pattern is under investigation in both theoretical aspect and data storage application. In this work, the effect of solid and liquid substrates on the nanoparticle assembly was compared. Iron (III) dibenzoylmethane (Fe(dbm)3) was used as an alternative reagent to highly toxic iron pentacabonyl (Fe(CO)5) in the co-reduction...
Excess energy in machinery can be stored for reuse in forms of the kinetic energy of the flywheel, composed of a permanent magnetic ring. In the simulation of interaction of flywheel rings with superconducting bearing with COMSOL Multiphysics version 5.2 program, a Neodymium-Iron-Boron magnetic ring of 20 mm in inner radius, 80 mm in outer radius, and 23 mm in thickness has a remanent magnetic...
Magnetic refrigeration is a new technology based on the reduction of temperature below the room temperature by magnetocaloric effect. The Comsol mutiphysics and Poisson Superfish program are used to simulate the optimum structure for generating the maximum magnetic flux density in the air gap. A neodymium-iron-boron permanent magnets has a remanent flux density of 1.44 Tesla and relative...
Cellulose has attracted much attention from researchers because of its unique properties.Whereas cellulose is a non-conductive, carbon nanotube (CNT) shows higher conductivity and thermal conductivity. CNT/cellulose composite fibers are prepared with 2 conditions:CNT concentration and mixing temperature. CNT/cellulose composite has been characterized by Ultraviolet–visible spectrophotometer...
Graphene nanoribbon (GNR), a narrow stripe of graphene layer, has recently gained much attention due to its special electronic band gap and very large surface to volume ratio properties promising for numerous applications such as graphene-based electronic devices, energy storage and electromechanical sensors. GNR can be fabricated by several methods including unzipping of carbon nanotubes,...
Now, the research field of perovskite based solar cells has recently been developed as the most promising candidate for next-generation because of their high efficiency solar cell technology that is compatible with low-cost, low-temperature processing, long-term stability and simple structure of solar cells production such as the hybrid halide perovskite CH3NH3PbI3 in solar cells have high...
Barium strontium titanate (BST) ceramics were prepared by the hybrid method between solid-state reaction (SR) and sol-gel combustion (SC) methods using urea as a fuel. The crystalline powders were prepared by the mixed precursors at SR:SC molar ratio of 1:0.3 calcined at 950$^o$C for 2 hours. The BST ceramics were made of the calcined powders by sintering at 1050-1350$^o$C and instigated the...
In this work, we report the textile-based gas sensor for ammonia (NH$_3$) detection using PANi/PEDOT:PSS coated on commercially cotton yarn. A laye- by-layer of textile-based gas sensor was prepared by a facile dip coating of poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) on the cotton yarn surface followed by coated a layer of polyaniline emeraldine base (PANi) on the top...
Bis-(3-triethoxysilylpropyl) tetrasulphide (TESPT) and 3-mercaptopropyltrimethoxysilane (MTMO) are used as silane coupling agent for silica fume. The modified silica fume is used as reinforcing filler in ethylene propylene diene monomer (EPDM) for lamp socket rubber. The cure characteristics, rubber mechanical properties and fogging phenomenon of lamp socket rubber are investigated. Test...
