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Articles 3541 - 3570 of 3637

Full-Text Articles in Engineering

Welding Residual Stresses In Two Competing Single V-Butt Joints, P Wongpanya Jul 2009

Welding Residual Stresses In Two Competing Single V-Butt Joints, P Wongpanya

Journal of Metals, Materials and Minerals

During fabrication of welded components residual stresses are generated as a result of non-uniform temperature distribution during the welding and particularly the cooling processes. The residual stresses have a major effect on the overall performance of the components in service, especially when hydrogen is involved and the components might become prone to Hydrogen Assisted Cold Cracking (HACC). Up to the present, most of the welding standards and specifications to test the resistance of welds against HACC test are without consideration of the restraint intensity provided by the surrounding structure. This may lead to a misunderstanding of the welding heat treatment …

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Creep-Rupture Behavior Of Die-Cast Magnesium Alloys, Y B. Unigovski Jul 2009

Creep-Rupture Behavior Of Die-Cast Magnesium Alloys, Y B. Unigovski

Journal of Metals, Materials and Minerals

It is found that the relationship between the time-to-rupture tr and the time to the onset of tertiary creep tοt (tr /tot) in die-cast Mg-9Al alloy is equal to 1.3 and independent of stress, test temperature and diecasting parameters over the range examined. It is shown that the introduction of creep-rupture strain into Monkman-Grant relation modified by Dobeš and Milička demonstrates only the deviation range of the minimum creep rate from the average creep rate. The apparent activation energy Ec of creep is below the value of magnesium self-diffusion energy ESD up to 175o C. At higher temperatures, Ec > ESD, …

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Effect Of Electron Donor On Pe Polymerization, A Thongdonjui, W Trakarnpruk, R H. Strauss Jul 2009

Effect Of Electron Donor On Pe Polymerization, A Thongdonjui, W Trakarnpruk, R H. Strauss

Journal of Metals, Materials and Minerals

Ziegler-Natta catalyst was prepared from colloidal MgCl2 (from reaction between magnesium ethyl carbonate and aluminium sesquichloride, Al2Et3Cl3) followed by contact with TiCl4. Al/Mg and Ti/Mg molar ratios were studied as parameters affecting the catalyst synthesis. Catalytic performance and effect of electron donor on ethylene polymerization were investigated. Results showed that addition of electron donor (ethyl benzoate) increased activity balance when polymerizations were performed under hydrogen pressure of 1 bar and 3 bars. The morphology of the polymer can be improved while fine content of the polymer was reduced by addition of dicyclopentyl dimethoxysilane. A productivity of 17.3 and 15.0 kg …

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Method For The Preparation Of Secondary Emulsions Of Fish Oil In Water, S Siramard, L Dubas, S T. Dubas Jul 2009

Method For The Preparation Of Secondary Emulsions Of Fish Oil In Water, S Siramard, L Dubas, S T. Dubas

Journal of Metals, Materials and Minerals

The method for the preparation of stable secondary emulsion has been detailed and discussed in terms of polymer capping and emulsion ratio. The dispersion of omega-3 oil in water by emulsion stabilized with casein was further coated with a polycationic polyelectrolyte, Poly (dially dimethyl ammonium chloride). The stability of the emulsion was studied by turbidity measurements using a UV-visible spectrophotometer. The particles size of the primary and secondary emulsion was investigated by light scattering and zeta potential measurements. Results shown in this article provide some details about the mechanism of the formation of secondary emulsion, mainly regarding the polymer/emulsion-mixing ratio.

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Determination Of Yield Behaviour Of Boron Alloy Steel At High Temperature, J Tungtrongpairoj, V Uthaisangsuk, W Bleck Jul 2009

Determination Of Yield Behaviour Of Boron Alloy Steel At High Temperature, J Tungtrongpairoj, V Uthaisangsuk, W Bleck

Journal of Metals, Materials and Minerals

The hot tensile test is a basic material testing method for investigation of the mechanical properties of steel at high temperature conditions. In industrial hot sheet forming processes such as hot stamping and hot gas metal forming, the influences of temperature and strain rate on microstructure and material behaviour play a significant role. In this work, sheet samples of steel grade 22MnB5 were examined using a hot deformation simulator. Different temperatures between 900 and 1200°C, which are above Ac3, and strain rates between 0.001 and 0.1 s-1 were considered. During the tensile test, a laser speckle extensometer (LSE) was deployed …

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Interfacial Polymerization Of Water-Soluble Polyaniline And Its Assembly Using The Layer-By-Layer Technique, E Detsri, S T. Dubas Jul 2009

Interfacial Polymerization Of Water-Soluble Polyaniline And Its Assembly Using The Layer-By-Layer Technique, E Detsri, S T. Dubas

Journal of Metals, Materials and Minerals

The interfacial polymerization of aniline has been used to prepare water-soluble polyaniline. Polyaniline was made water-soluble by interfacial polymerization in the presence of poly(styrene sulfonated, sodium salt) (PSS), which acted as bundling agent to provide water solubility. The prepared polymer composite was later used for the fabrication of polyaniline nano-thin films using the layer-by-layer (LbL) self-assembly technique. Film produced by the LbL technique can be used in electro-chromic films, sensors or electro-catalytic films depending on the type of architectures. This paper first presents, a brief review on conducting polymer prepared by interfacial polymerization. Special interest is given to the synthesis …

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Mechanical Property Improvement Of Upe Resin From Glycolyzed Pet With Commercial Upe Resin, T Limpiti, P Potiyaraj Jul 2009

Mechanical Property Improvement Of Upe Resin From Glycolyzed Pet With Commercial Upe Resin, T Limpiti, P Potiyaraj

Journal of Metals, Materials and Minerals

The aim of this research paper is to improve mechanical properties of cured unsaturated polyester (UPE) resin prepared from glycolyzed PET by mixing with a commercial UPE resin. Postconsumer PET bottles were depolymerized by glycolysis reaction in excess propylene glycol at 190ºC in the presence of zinc acetate as a catalyst. The glycolyzed product was polyesterified with maleic anhydride and mixed with styrene monomer in order to obtain UPE resin. The prepared UPE resin was mixed with a commercially available general purpose grade UPE resin at various ratios. The mixed resins were cured using methyl ethyl ketone peroxide and cobalt …

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Characterizations Of Fibers Produced From Polypropylene/Silica Composite, N Srisawat, M Nithitanakul, K Srikulkit Jul 2009

Characterizations Of Fibers Produced From Polypropylene/Silica Composite, N Srisawat, M Nithitanakul, K Srikulkit

Journal of Metals, Materials and Minerals

Fumed silica particles filled polypropylene (PP) filament fibers were prepared by melt spin pilot plant. First, virgin PP and silicas(hydrophilic and hydrophobic) were premixed using twin screw extruder to prepare silica containing PP composite resin. Then, the resin composite was again mixed with virgin PP and spun into filaments with various filler loadings in the range of 0.5 - 2.5 wt%. The characterizations of spun composite fibers including crystallization temperature (DSC analysis), polymer orientation (sonic modulus) and the fine structure (XRD) were studied. XRD results showed β-form crystallinity peak in x-ray pattern of fiber drawn with low take-up speed (300 …

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Preparation And Characterization Of Particles From Chitosan With Different Molecular Weights And Their Trimethyl Chitosan Derivatives For Nasal Immunization, W Boonyo, H E. Junginger, N Waranuch, A Polnok, T Pitaksuteepong Dec 2008

Preparation And Characterization Of Particles From Chitosan With Different Molecular Weights And Their Trimethyl Chitosan Derivatives For Nasal Immunization, W Boonyo, H E. Junginger, N Waranuch, A Polnok, T Pitaksuteepong

Journal of Metals, Materials and Minerals

According to previous studies, molecular weights (MW) of chitosan presented an influence on the level of immune response to model antigen when administering with chitosan through nasal route. Moreover, trimethyl chitosan (TMC) with a degree of quaternization (DQ) of 40%, chitosan derivatives, was also shown to be the most potent nasal OVA delivery platforms compared to TMC with DQ of 20% and 60% in mice model. The aims of this study were to prepare particles from chitosan with difference MW and their TMC derivatives (DQ = 40%) and to characterize size, zeta potential, loading efficiency and release profile in order …

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Chitosan/Calcium Phosphate Composites Scaffolds Prepared By Membrane Diffusion Process, P Thanaphat, P Thunyakitpisal, W Techaboonyakiat Dec 2008

Chitosan/Calcium Phosphate Composites Scaffolds Prepared By Membrane Diffusion Process, P Thanaphat, P Thunyakitpisal, W Techaboonyakiat

Journal of Metals, Materials and Minerals

Hydroxyapatite (Ca10(PO4)6(OH)2, HAp) and Dicalcium phosphate dihydrate (CaHPO4.H2O, DCPD) were homogeneously hybridized into chitosan solution by membrane diffusion process. The threedimensional scaffolds were obtained by freeze-drying process. The organic and inorganic contents of scaffold were determined by using thermogravimetry analysis (TGA). The surface morphology of the scaffold and characteristic of calcium phosphate were investigated by scanning electron microscope (SEM), energy dispersive X-ray spectrometer (EDX), and X-ray diffraction (XRD), respectively. Compressive modulus was also determined by dynamic mechanical analysis (DMA). The hybridized inorganic content ranges from 35-45%. Both chitosan/HAp and chitosan/DCPD scaffolds showed interconnected porous structure. The calcium to phosphorus ratios …

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Preparation Of N-Acetyl-D-Glucosamine Using Enzyme From Aspergillus Sp., P Setthakaset, R Pichyangkura, A Ajavakom, M Sukwattanasinitt Dec 2008

Preparation Of N-Acetyl-D-Glucosamine Using Enzyme From Aspergillus Sp., P Setthakaset, R Pichyangkura, A Ajavakom, M Sukwattanasinitt

Journal of Metals, Materials and Minerals

N-acetyl-D-glucosamine (GlcNAc) is one of the basic constituents of mammal cartilage, which is known to help repair deteriorating cartilage and relieve pain and inflammation in osteoarthritis patients. The preparation of GlcNAc from squid pen β-chitin by using Aspergillus sp. chitinase in enzymatic hydrolysis is studied. The cultivation of the fungus in colloidal chitin minimum media at pH 3.5 and 40°C for 5 days gives the highest chitinolytic activity of 3.1 U/mL. The crude enzyme obtained from the the cultivation is used in the hydrolysis of milled squid pen β-chitin (50μm) at pH 4 (acetic acid 2M) and 45°C using 22 …

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Influence Of Reinforced Plastomers On Injection Moulds Wear, A Guzanová, J Brezinová Dec 2008

Influence Of Reinforced Plastomers On Injection Moulds Wear, A Guzanová, J Brezinová

Journal of Metals, Materials and Minerals

The contribution deals with wear of injection moulds based on aluminium alloy Alumec 89 in friction couples with plastomers reinforced with different glass fibres content. Friction relations in injection moulding were simulated by adhesion dry wear test with help of Amsler equipment with area contact of friction couple. Wear intensity was evaluated by friction coefficient and relative wear by weight loss. Simultaneously, changes of aluminium alloy surface morphology after wear in particular friction couples were analysed.

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Production Of Sponge Rubber For Monolayer Rubber Stamp Using Salt Leaching Method, W Trakanpruk, Y Rodthong Dec 2008

Production Of Sponge Rubber For Monolayer Rubber Stamp Using Salt Leaching Method, W Trakanpruk, Y Rodthong

Journal of Metals, Materials and Minerals

Sponge rubber used for monolayer rubber stamp was produced from nitrile butadiene rubber (NBR). Open cells in sponge rubber were created using salt leaching method. Effect of size and amount of sodium chloride which was used as a water soluble salt on the creation of open cells in the rubber was investigated. Carbon black was used as a filler. A different type of surfactant was added to increase the leaching out of salt from the rubber. Cure characteristics of the compound rubbers: maximum torque, minimum torque, scorch time and cure time as well as hardness of the prepared sponge rubber …

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Chitin Nanowhisker And Chitosan Nanoparticles In Protein Immobilization For Biosensor Applications, P Na Nakorn Dec 2008

Chitin Nanowhisker And Chitosan Nanoparticles In Protein Immobilization For Biosensor Applications, P Na Nakorn

Journal of Metals, Materials and Minerals

In this study, bovine serum albumin (BSA) was used as a model protein for the optimization of protein immobilization on chitin nanowhisker and chitosan nanoparticles under different conditions. Chitosan nanoparticles showed better results than chitin in this immobilization purpose. The immobilization at 15 minutes, pH 6 and 20-25°C was the optimal condition. Subsequently, glucose oxidase (GOD), enzyme used for glucose determination, was applied in order to investigate the optimum immobilization condition on chitosan nanoparticles. The optimal condition prove to…at pH 7, 30°C and 0.5 mg/ml of initial GOD concentration via immobilization at 15 minutes. Chitin nanowhisker and chitosan nanoparticles in …

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Preparation Of Ultrafine Silver Powder Using Glycerol As Reducing Agent, E Nisaratanaporn, K Wongsuwan Dec 2008

Preparation Of Ultrafine Silver Powder Using Glycerol As Reducing Agent, E Nisaratanaporn, K Wongsuwan

Journal of Metals, Materials and Minerals

The production of silver nanoparticles and sub-micron particles can be achieved by silver alkoxide from silver sulfate and subsequently reducing with glycerol. To reduce the particle size of silver sulfate precursors, ball milling was employed to reduce particle sizes down to 0.81 microns. However, silver sulfate without grinding provided smaller particle sizes of silver particles as opposed to ground specimens. Stirring silver alkoxide simultaneously was efficient to provide for uniform distribution of silver powder. The silver powder thus produced had brain-like shape consisted of very fine aggregate silver particles. The yield of silver powder was in the range of 95-99 …

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Demonstration Of The Ntc Ceramic Application For Temperature Measurement And Control Using The Labview-Based Measurement System, T Panmatarith, K Poatong Dec 2008

Demonstration Of The Ntc Ceramic Application For Temperature Measurement And Control Using The Labview-Based Measurement System, T Panmatarith, K Poatong

Journal of Metals, Materials and Minerals

In the present paper, ZnO+0.01SnO2 ceramics were prepared using a standard ceramic method. We present the NTC ceramic application for temperature measurement and control using the LabVIEW-based measurement system. The measured resistance of the sample at room temperature was about 6.5 kΩ. The electrical resistance versus temperature of the sample was measured. The negative temperature coefficient of resistance of the sample was -1.018 %/°C. This sample showed NTC effect and exhibited NTC resistor, indicating their potential application as temperature sensor with low cost. It can be used as temperature sensor by using the NTC effect . The measured temperature (T) …

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Properties Evaluation Of Sodium Nitrite Treated Chitosan-Cotton Fabric, S Srisuk, K Srikulkit Dec 2008

Properties Evaluation Of Sodium Nitrite Treated Chitosan-Cotton Fabric, S Srisuk, K Srikulkit

Journal of Metals, Materials and Minerals

In this study, chitosan coated-cotton fabric was prepared and then treated with sodium nitrite under mild condition, aiming at the partial removal of surface-chitosan in order to solve the problems of surface dyeing and fabric stiffness. The results showed that sodium nitrite treated chitosan-fabric exhibited an improvement of dyeability (higher dye exhaustion and color strength) when compared to untreated fabric. The improvement in dyeability was due to the availability of chitosan amino groups which had an affinity to anionic dyes including reactive dyes. Other fabric properties were evaluated. The results showed that color fastness properties (crocking fastness and light fastness) …

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Application Of Chitosan In Rice Production, S Boonlertnirun, C Boonraung, R Suvanasara Dec 2008

Application Of Chitosan In Rice Production, S Boonlertnirun, C Boonraung, R Suvanasara

Journal of Metals, Materials and Minerals

Chitosan is a natural biopolymer which stimulates growth and increases yield of plants as well as induces the immune system of plants. The objectives of this study were to determine appropriate applications for increasing of the rice yield. The experiment was performed with randomized complete block design ( RCBD) with four replications. Four treatments were done as follows : no chitosan application, seed soaking with chitosan solution, seed soaking and soil application with chitosan solution and seed soaking and foliar spraying with chitosan solution. The results showed that application of chitosan by seed soaking and soil application four times throughout …

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Factors Affecting Preparations Of Chitosan Microcapsules For Colonic Drug Delivery, K Huanbutta, M Luangtana-Anan, P Sriamornsak, S Limmatvapirat, S Puttipipatkhachorn, J Nunthanid Dec 2008

Factors Affecting Preparations Of Chitosan Microcapsules For Colonic Drug Delivery, K Huanbutta, M Luangtana-Anan, P Sriamornsak, S Limmatvapirat, S Puttipipatkhachorn, J Nunthanid

Journal of Metals, Materials and Minerals

This work aimed at studying factors affecting preparations of chitosan microcapsules for colonic drug delivery. Chitosan microcores (CS, 45kDa, 87% degree of deacetylation) containing diclofenac sodium (DS) coated with Eudragit®S100 (ED) were prepared by a desolvation technique. Sodium sulfate was used as a desolvating agent and the drying process was freeze-drying. Factors affecting morphology, particle size and zeta potential of microcapsules were evaluated, i.e. weight ratio of DS:CS:ED, surfactant (polysorbate 80), anti-adherent (silicon dioxide), and the use of sonication or homogenization in preparation processes. The weight ratio of DS:CS:ED at 1:2:6 provided the smallest microcapsules of about 82.37±1.61 micrometer in …

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Fabrication Of Porous Bioactive Glass-Ceramics Via Decomposition Of Natural Fibres, P Sooksaen, S Suttiruengwong, K Oniem, K Ngamlamiad, J Atireklapwarodom Dec 2008

Fabrication Of Porous Bioactive Glass-Ceramics Via Decomposition Of Natural Fibres, P Sooksaen, S Suttiruengwong, K Oniem, K Ngamlamiad, J Atireklapwarodom

Journal of Metals, Materials and Minerals

Porous bio glass-ceramics were prepared via natural fibres burning-out process. Glass-ceramics were fabricated by controlled crystallization of suitable glass compositions to give required crystalline phase/s. Porous structure was formed alongside during burning-out of natural fibres. Three glass batches were prepared in the SiO2-CaO-P2O5-K2O-Na2O-CaF2 glass system, then melted, quenched and milled to give fine glass powders. DTA thermograms for the three glass compositions showed crystallization temperatures between 720 and 760°C and Tg ranging between 508 and 645°C. Porous glass-ceramics were characterized for bulk density, phase evolution and microstructures. Different compositions resulted in different bulk densities and phases that crystallized out. Fluorapatite …

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Water Soluble Chitosan As An Environment-Friendly Coagulant In Removal Of Rubber Particles From Skim Rubber Latex, R Werathirachot, P Danwanichakul, C Kongkaew, S Loykulnant Dec 2008

Water Soluble Chitosan As An Environment-Friendly Coagulant In Removal Of Rubber Particles From Skim Rubber Latex, R Werathirachot, P Danwanichakul, C Kongkaew, S Loykulnant

Journal of Metals, Materials and Minerals

Water soluble chitosan, dissolved in hot deionized water to obtain 0.8% solution, was used for the coagulation-flocculation of skim natural rubber latex. The efficiency of coagulation-flocculation of skim rubber latex without pH adjustment was much poorer than that of neutral skim rubber latex. When adding chitosan solution to the neutral skim rubber latex with a rubber content of 5.300 %wt/vol until the concentration of chitosan in the dispersion was 0.107%, the phase separation between rubber particles and yellow serum was clearly observed. At this condition, the removal efficiency of skim rubber particles was found to be the best among all …

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Fabrication Of Al/Al2o3 Composite By Powder Metallurgy Method From Aluminum And Rice Husk Ash, C Dhadsanadhep, T Luangvaranunt, J Umeda, K Kondoh Dec 2008

Fabrication Of Al/Al2o3 Composite By Powder Metallurgy Method From Aluminum And Rice Husk Ash, C Dhadsanadhep, T Luangvaranunt, J Umeda, K Kondoh

Journal of Metals, Materials and Minerals

Fabrication of Al-4wt.%Cu /Alumina composite was reported. The method of fabrication was powder metallurgy by in-situ reaction to form alumina during fabrication. Starting materials were mixture of aluminum, copper, and silica powders. Silica is in form of rice husk ash. The mixture was cold compacted, and sintered at 650°C for 1 h. Hot forging was carried out to further consolidate the sintered billet, followed by 10-h heat treatment at temperatures between 590 to 650°C. Phase analysis by XRD confirmed that in-situ reaction between silica and aluminum powders occurred during heat treatment at temperatures above 590°C. The products of reaction were …

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Diffusion Bonding Of Stainless Astm A240 Grade 304 In Double Side Flux Cored Arc Welding, S Pitaknorachon, B Poopat Jul 2008

Diffusion Bonding Of Stainless Astm A240 Grade 304 In Double Side Flux Cored Arc Welding, S Pitaknorachon, B Poopat

Journal of Metals, Materials and Minerals

Double side flux cored arc welding (DS-FCAW) has been developed from conventional flux cored arc welding (FCAW). DS-FCAW, dual torches are used by placing an opposite to each other and welding on both sides simultaneously. The objective of this research paper is to investigate diffusion bonding effect due to DS-FCAW. Stainless steel ASTM A240 Grade 304 was studied. Other welding parameters were set constant except welding current and voltage. Diffusion bonding was observed even though weld profiles from macro inspection showed lack of penetration by weld metal in all experiments. It can be concluded that, at certain conditions, the welds …

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Improvement Of Mechanical Properties For En Aw 6082 Aluminium Alloy Using Equal-Channel Angular Pressing (Ecap) And Post-Ecap Aging, M Fujda, T Kvačkaj, K Nagyová Jul 2008

Improvement Of Mechanical Properties For En Aw 6082 Aluminium Alloy Using Equal-Channel Angular Pressing (Ecap) And Post-Ecap Aging, M Fujda, T Kvačkaj, K Nagyová

Journal of Metals, Materials and Minerals

The mechanical properties and microstructure of EN AW 6082 aluminium alloy subjected to severe plastic deformation and aging treatment were compared with those of the extruded and artificially aged state (initial state). The initial state of alloy subjected to solution annealing and quenching was severely deformed at ambient temperature by equal channel angular pressing (ECAP) following route C up to three passes. Polyedric microstructure of initial state was considerably changed by the repetitive ECA-pressing. Deformation bands with different density of slip lines were observed in microstructure of ECAPed and aged states, which indicated non-uniform deformation across the cross-section of ECAPed …

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Surface Modification Of Bricks By Chitosan Coatings, S Nilpairach, S T. Dubas Jul 2008

Surface Modification Of Bricks By Chitosan Coatings, S Nilpairach, S T. Dubas

Journal of Metals, Materials and Minerals

Bricks were successfully modified by application of a chitosan coating in order to provide their surface with a water repellant character. The chitosan coating was prepared by depositing solutions of variable chitosan concentration (1% or 2.5% w/w) onto the brick surface and let to dry under ambient condition. In order to improve the water repellant property, the films were cross-linked with a 1% solution of sodium citrate, sodium sulfate or sodium tri - polyphosphate. The effect of the chitosan concentration on the morphology of the coating at the brick surface was observed by scanning electron microscope (SEM). It was found …

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Sintered Materials Prepared From Stainless Steel Series 300 And 400 Powders, M Morakotjinda, N Kuljittipipat, N Poolthong, N Tosangthum, P Wila, R Krataitong, T Yodkaew, O Coovattanachai, B Vetayanugul, R Tongsri Jul 2008

Sintered Materials Prepared From Stainless Steel Series 300 And 400 Powders, M Morakotjinda, N Kuljittipipat, N Poolthong, N Tosangthum, P Wila, R Krataitong, T Yodkaew, O Coovattanachai, B Vetayanugul, R Tongsri

Journal of Metals, Materials and Minerals

Some sintered materials were prepared from mixtures of stainless steel series 300 and series 400 powders. The sintered stainless steels consisted of both austenitic and ferritic phases so they were designated as sintered duplex stainless steels (SDSSs). Microstructures and properties of the SDSSs were characterized and tested. Most SDSSs, except the 310L powder-base SDSSs, showed improved tensile strengths and hardness but exhibited inferior ductility, compared to those of the sintered stainless steels series 300. The 304L-410L SDSS showed promising mechanical properties. This SDSS were further investigated by varying weight ratio of 304L and 410L powders. It was found that sintered …

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Calcium Phosphate Film Coating On Titanium Substrate By Electrochemical Deposition, D P. Kashima, A Rakngarm Jul 2008

Calcium Phosphate Film Coating On Titanium Substrate By Electrochemical Deposition, D P. Kashima, A Rakngarm

Journal of Metals, Materials and Minerals

Calcium phosphate film on titanium substrate was achieved by electrochemical method in four different kinds of electrolyte. The pure titanium metal (99.99%) with 0.8 cm in width and 2 cm in length was used as a substrate and it was subsequently etched by 2M HF for 1 minute before electrochemical deposition. Calcium phosphate film could form at a different current density for each kind of electrolyte as follows: 10 mA/cm2 for MCPM based aqueous solution, 20 mA/cm2 for MCPM based aqueous solution with ions addition, 10 mA/cm2 and 20 mA/cm2 for MCPM based 20%V/V ethanol and 50%V/V ethanol solution, respectively. …

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Morphology Controlled Calcium Ortho Phosphates Induced By Chemical Additions Under Hydrothermal Reaction, D P. Kashima, E Kongkul, T Daopradubwon Jul 2008

Morphology Controlled Calcium Ortho Phosphates Induced By Chemical Additions Under Hydrothermal Reaction, D P. Kashima, E Kongkul, T Daopradubwon

Journal of Metals, Materials and Minerals

Morphology controlled calcium orthophosphates under hydrothermal reaction was achieved using saturated solution of monocalcium phosphate monohydrate (MCPM) as a starting material. MCPM saturated solution was hydrothermally treated at 180°C for 4 and 12 hrs. Citric acid as a chelating agent and a mixed solution of NaNO3 and NaF were individually added into the reactor. The morphologies, phases and microstructures of the obtained products were characterized by optical microscope (OM), X-ray diffraction (XRD) and scanning electron microscope (SEM), respectively. Irregular shape crystals were obtained when a saturated solution of MCPM was autoclaved at 180°C for 4 hrs. Though citric acid was …

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Current Status Of Nanotechnology Consumer Products And Nano-Safety Issues, N Chuankrerkkul, S Sangsuk Jul 2008

Current Status Of Nanotechnology Consumer Products And Nano-Safety Issues, N Chuankrerkkul, S Sangsuk

Journal of Metals, Materials and Minerals

This paper is divided into 2 parts to present a review on nanotechnology consumer products ('Nanotech' products) and a current status on 'Nano-Safety' issue. The first part focuses on up-to-date information of 'Nanotech' products that were already on the market as reported by Project on Emerging Nanotechnologies of the Woodrow Wilson International Center for Scholars. There are more than 500 products for a variety of applications, among which health and fitness products are the largest category. The products in this group consist of clothing, cosmetics and sunscreens. Silver is the most commonly used material, followed by carbon in the forms …

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Effect Of Limestone Dust On The Properties Of Thai Pottery Sintering At Low Temperature, S Sangsuk, S Khunthon, S Saenapitak, S Nilpairach Jul 2008

Effect Of Limestone Dust On The Properties Of Thai Pottery Sintering At Low Temperature, S Sangsuk, S Khunthon, S Saenapitak, S Nilpairach

Journal of Metals, Materials and Minerals

Limestone dust from a limestone crushing plant was used as an additive in pottery clay for this experiment. After the limestone dust was sieved through a 35 mesh stainless steel sieve, it was mixed with Angthong pottery clay at various contents. Samples with and without limestone dust were sintered at 600, 700, 900, and 1000o C. Because of limestone blowing for samples with limestone dust sintered at 900 and 1000o C, physical property measurement was performed only for samples sintered at 600 and 700o C. While sintering at low temperatures (600 and 700o C), physical properties of samples with limestone …

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