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Corrosion Study On Low Alloy High Phosphorus Steel, B K. Jena, N Gupta, B Singh, G Sahoo Jul 2014

Corrosion Study On Low Alloy High Phosphorus Steel, B K. Jena, N Gupta, B Singh, G Sahoo

Journal of Metals, Materials and Minerals

The effect of P on corrosion behaviour of low alloy steels exposed for one month cyclic wet/dry salt spray was investigated and compared with low carbon steel. Electrochemical Impedance Spectroscopy (EIS) results revealed that the rust resistance (Rrust) increased with the number of salt spray test cycles. The higher phosphorus content steel (G12) exhibited higher rust resistance (Rrust) than that of low phosphorus content steels (SCR & G11), while similar corrosion rate was noticed from the Tafel extrapolation study in 3.5% NaCl solution for all the test samples. All steels revealed ferrite pearlite microstructure. The larger ferrite grain of G12 …


Agronomic Benefits Of Durian Shell Biochar, N Prakongkep, R J. Gilkes, W Wiriyakitnateekul Jul 2014

Agronomic Benefits Of Durian Shell Biochar, N Prakongkep, R J. Gilkes, W Wiriyakitnateekul

Journal of Metals, Materials and Minerals

This study investigated the chemical properties of durian shell biochar which is used as a soil amendment. It can act as a carbon sink and as a means to improve crop yield. Plant nutrient elements in this biochar are in crystalline minerals located within the complex pore structure therefore biochar production from wastes could be a very good way to reduce demand for fertilizers. XRD and SEM-EDS results demonstrate that the numerous minerals in biochar are highly soluble, such as archerite (KH2PO4), chlorocalcite (KCaCl3), kalicinite (KHCO3), and sylvite (KCl) with small amounts …


Shape Fixity And Shape Recovery Characteristics Of Aliphatic Epoxy-Benzoxazine Shape Memory Polymer, T Tanpitaksit, M Okhawilai, S Rimdusit Jul 2014

Shape Fixity And Shape Recovery Characteristics Of Aliphatic Epoxy-Benzoxazine Shape Memory Polymer, T Tanpitaksit, M Okhawilai, S Rimdusit

Journal of Metals, Materials and Minerals

Shape memory polymers (SMPs) are polymers that can fix the temporary shape and recover to the permanent shape by external stimuli. Epoxy resins are an important family of SMPs due to their excellent stability, thermomechanical endurance and the high values of shape fixity. However, epoxide ring opening polymerization required a curing agent which possesses some disadvantages such as high cost, toxic problem to the user and corrosion to the processing apparatus. In this research, novel series of SMPs were prepared from aliphatic epoxy as soft segment and benzoxazine resin (BA-a) as hard segment. Additionally, benzoxazine resin can also function as …


Development Of Electronic Packages From Polypropylene/Ethylene Propylene Rubber Blends: A Double Percolation Approach, S Phromdee, P Lorjai, S Tiptipakorn, S Rimdusit Jul 2014

Development Of Electronic Packages From Polypropylene/Ethylene Propylene Rubber Blends: A Double Percolation Approach, S Phromdee, P Lorjai, S Tiptipakorn, S Rimdusit

Journal of Metals, Materials and Minerals

Volume resistivity of less than 104 W.cm is required for typical electrically conductive packages. Conductive polypropylene (PP) packages with the above level of conductivity value can be achieved by a use of carbon black (CB) as conductive filler. To maintain processability of PP with low cost, minimal amount of carbon black is preferable in the conductive composites. By introducing a second polymer with immiscible or partially miscible nature to the first polymer, and if the conductive filler is localized in one polymer phase, a system of double percolation with minimal filler content can be achieved. In this work, electrically conductive …


Property Enhancement Of Polybenzoxazine Modified With Maleic Anhydride, W Punuch, M Okhawilai, S Rimdusit Jul 2014

Property Enhancement Of Polybenzoxazine Modified With Maleic Anhydride, W Punuch, M Okhawilai, S Rimdusit

Journal of Metals, Materials and Minerals

One seemingly shortcoming of polybenzoxazine is its relatively high rigidity. Therefore, various efforts have been attempted to toughen polybenzoxazine such as by alloying with more flexible monomers or polymers e.g. urethane elastomers or flexible epoxy. The alloying of polybenzoxazine with those resins or polymers has been reported to show synergy in some properties thus economically provide a novel class of resin systems with superior performance. In this work, polybenzoxazine alloys were prepared from bisphenol-A-aniline based benzoxazine resin (BA-a) and maleic anhydride (MA) in N, N-Dimethyformamide (DMF) solvent. The miscible monomer mixture was easily transformed into transparent polymer alloys by thermal …


วัสดุไททาเนียผสมซีเมนต์เคลือบบนเม็ดแก้วซิลิกาสำหรับใช้เป็นตัวเร่งปฏิกิริยาเชิงแสงเพื่อแตกสลายสารประกอบฟีนอลในน้ำเสียที่นำกลับมาใช้ซ้ำได้, กมลวรรณ ปินะโต Jan 2014

วัสดุไททาเนียผสมซีเมนต์เคลือบบนเม็ดแก้วซิลิกาสำหรับใช้เป็นตัวเร่งปฏิกิริยาเชิงแสงเพื่อแตกสลายสารประกอบฟีนอลในน้ำเสียที่นำกลับมาใช้ซ้ำได้, กมลวรรณ ปินะโต

Chulalongkorn University Theses and Dissertations (Chula ETD)

น้ำเสียจากโรงงานผลิตสารเคมีมักปนเปื้อนสารเคมีที่ใช้ในกระบวนการผลิตสูงเกินกว่ามาตรฐานอุตสาหกรรม จึงจำเป็นต้องควบคุมให้อยู่ในมาตรฐานก่อนปล่อยออกสู่สิ่งแวดล้อม น้ำเสียจากโรงงานผลิตฟีนอลปนเปื้อนสารอินทรีย์หลายชนิด เช่น คิวมีนไฮโดรเปอร์ออกไซด์ (CHP) ไดเมทิลฟีนิลคาร์บินอล (DMPC) และอะซิโตฟีโนน (ACP) ค่า pH มีค่า 12.7 งานวิจัยนี้มีจุดประสงค์ในการนำไททาเนีย (TiO2) ซึ่งเป็นตัวเร่งปฏิกิริยาเชิงแสงที่มีศักยภาพสูงและมีอายุการใช้งานยาวนานมาแตกสลายสารอินทรีย์ที่ปนเปื้อนในน้ำเสีย เพื่อความสะดวกในการนำกลับใช้ซ้ำ ไททาเนีย P25 จึงถูกนำมาเคลือบบนวัสดุรองรับ (Ecolite® sphere, EC) ด้วยเทคนิคแกรนูเลตและใช้แคลเซียมอลูมินาซีเมนต์ (AC) เป็นวัสดุเชื่อมประสานเกิดเป็น EC+AC+15wt% TiO2 P25 และศึกษาผลของปัจจัยต่างๆ ที่มีต่อการแตกสลาย CHP ได้แก่ แสงยูวี ปฏิกิริยาเชิงแสงของไททาเนีย P25 ความเข้มข้นเริ่มต้นและอัตราเร็วของ CHP พบว่าปฏิกิริยาเชิงแสงของไททาเนีย P25 ความเข้มข้นเริ่มต้นของ CHP และอัตราเร็วของ CHP มีบทบาทอย่างมากต่อการแตกสลายของ CHP จากนั้นศึกษาความสามารถในการใช้ซ้ำของ EC+AC+15wt% TiO2 P25 พบว่าเมื่อผ่านการทดสอบการแตกสลาย CHP 2,000 พีพีเอ็ม และน้ำเสียจากโรงงานผลิตฟีนอลจำนวน 7 ครั้ง พบว่ามีประสิทธิภาพการแตกสลาย CHP อยู่ในช่วง 90-100% และค่าคงที่อัตราอยู่ในช่วง 0.0089 ถึง 0.0171 ต่อนาที ต่อมาศึกษาประสิทธิภาพของ EC+AC+15wt% TiO2 P25 ในการแตกสลายสารอินทรีย์ชนิดอื่นๆได้แก่ DMPC ACP และฟีนอล พบว่าอัตราการเกิดปฏิกิริยาการแตกสลายสารอินทรีย์ของ EC+AC+15wt% TiO2 P25 คือ CHP > DMPC > ACP > Phenol ตามลำดับ ข้อมูลดังกล่าวสามารถข้อบ่งชี้ถึงประสิทธิภาพของวัสดุดังกล่าวในการนำไปใช้ในงานบำบัดน้ำเสียได้


Flame Retardant Property Improvement Of Polyester Fiber Using Inorganic Additives, Warunee Wattanatanom Jan 2014

Flame Retardant Property Improvement Of Polyester Fiber Using Inorganic Additives, Warunee Wattanatanom

Chulalongkorn University Theses and Dissertations (Chula ETD)

This research focused on improving the flame retardancy of polyester and cotton/polyester blended fabrics using intumescent coating via layer-by-layer assembly technique with and without kaolin. The flammability, morphology, thermal stability and mechanical property of coated fabrics were investigated in comparison with uncoated fabrics. Branched polyethyleneimine and ammonium polyphosphate with and without kaolin were respectively used as polycationic and polyanionic to build up the multiple cationic/anionic pairs of layer by deposition technique. The SEM micrographs of coated fabrics compared with uncoated fabrics revealed as well as FT-IR analysis confirmed that layer-by-layer coatings were successfully applied onto the fabrics. The vertical burning …


Sio2-Included Cesium Polyoxotungstate Catalysts For Oxidation, W Trakarnpruk, W Kanjina Dec 2013

Sio2-Included Cesium Polyoxotungstate Catalysts For Oxidation, W Trakarnpruk, W Kanjina

Journal of Metals, Materials and Minerals

SiO2-included cesium polyoxotungstate catalysts were synthesized by a sol-gel method and characterizied by FTIR, XRD and N2 adsorption isotherms. XRD patterns prove that the cesium polyoxotungstate is uniformly dispersed in the silica network. The catalysts were used in oxidation of cyclohexane with H2O2. The products are cyclohexanol and cyclohexanone. The catalysts prepared by using a copolymer surfactant show higher surface area and exhibit higher activity. These catalysts are truly heterogeneous and can be reused at least 3 times.


Corrosion Behavior Of Tialn Film On Aisi 4140 Steel, T Wongpinij, P Wongpanya, C Euaruksakul, P Photongkam, N Witit-Anun Dec 2013

Corrosion Behavior Of Tialn Film On Aisi 4140 Steel, T Wongpinij, P Wongpanya, C Euaruksakul, P Photongkam, N Witit-Anun

Journal of Metals, Materials and Minerals

The corrosion behavior of uncoated and TiAlN coated on AISI 4140 steel were studied by an electrochemical technique in 3.5 wt% NaCl solution at pH value of 2, 7 and 10 at room temperature. The corrosion potential (Ecorr), pitting potential (Epit), corrosion rate (Rmmy) and passive region in polarization curves were analyzed and compared.After electrochemical testing, samples surface was characterized by scanning electron microscopy (SEM) with energy dispersive X-ray analysis (EDX) and X-ray photoemission electron microscopy (X-PEEM). The results indicated that the TiAlN coated samples yielded better corrosion resistance than the uncoated samples. The coated samples had lower corrosion rate …


Dolomite Stabilized Zirconia For Refractory Application : Part-I Phase Analysis, Densification Behavior And Microstructure Of Partial Stabilized Zirconia, R Prasad Rana, P Kumar, A Suvrajit Bal Dec 2013

Dolomite Stabilized Zirconia For Refractory Application : Part-I Phase Analysis, Densification Behavior And Microstructure Of Partial Stabilized Zirconia, R Prasad Rana, P Kumar, A Suvrajit Bal

Journal of Metals, Materials and Minerals

In the continuous casting of steel, Zircon and Zirconia based products are used due to its high thermal stability, excellent erosion resistance, self-opening, consistent casting speed and resistance to oxygen lancing during casting for removal of inclusion clogging and to streamline the flow. Higher casting sequences of molten steel CaO or MgO stabilized zirconia nozzles were being used and for industrial application point of view, dolomite stabilized zirconia (DSZ) could be a better substitute for the stabilization of zirconia. DSZ samples were prepared having 3,4,5,6 and 7 mole % of dolomite by solid state route using high purity monoclinic zirconia …


Effect Of Heat Treatment On Phase Transformation Of Tio2 And Its Reflectance Properties, K Archaapinun, N Witit-Anun, P Visuttipitukul Dec 2013

Effect Of Heat Treatment On Phase Transformation Of Tio2 And Its Reflectance Properties, K Archaapinun, N Witit-Anun, P Visuttipitukul

Journal of Metals, Materials and Minerals

Titanium dioxide (TiO2) anti reflection coating film applied for solar cell application, gains more interest due to the insufficient energy problems today. Titanium dioxide can be found in several forms, and the most stable phase is rutile. This research aims to study effect of heat treatment on phase transformation of TiO2 and its effect on reflectance property. Titanium dioxide film was coated on silicon wafer by DC magnetron sputtering to obtain 190 nm and 420 nm thicknesses. Then, it was heat treated at 900C for 1 and 4 hours under ambient atmosphere. Phases and surface morphologies before and after heat …


Mineralogical Characterization Of Pozuzo District's Soils Through Physical Techniques, M L Cerón Loayza, J B. Cabrejos, F Reyes Navarro Dec 2013

Mineralogical Characterization Of Pozuzo District's Soils Through Physical Techniques, M L Cerón Loayza, J B. Cabrejos, F Reyes Navarro

Journal of Metals, Materials and Minerals

We introduce a study on soils in three different fields of plantations in Pozuzo District, Oxapampa province, Peru. Two of the fields are cultivated and the third one has a degradation problem. In situ, in all, we collected 29 samples in the three plantations. We utilized analytical and physical techniques, namely, energy dispersive X-ray fluorescence, X-ray diffractometry, and transmission Msbauer spectroscopy; we complemented our research with a physical-chemical analysis to determine texture, pH, content of organic matter and cation interchange capacity. For all analyzed samples, the results of the analysis by energy dispersive X-ray fluorescence show the presence of the …


Comparison Of Ball-On-Disc And Taber Wear Tests In Assessing Wear Performance Of Electrolessly-Deposited Alloys, K Theeratatpong, S Danchaivijit, Y Boonyongmaneerat Dec 2013

Comparison Of Ball-On-Disc And Taber Wear Tests In Assessing Wear Performance Of Electrolessly-Deposited Alloys, K Theeratatpong, S Danchaivijit, Y Boonyongmaneerat

Journal of Metals, Materials and Minerals

In the industry, a Taber wear test is commonly employed to assess the wear resistance of coatings, which are applied on a panel of relatively large scales. On the other hand, other wear testing methods, such as ball-on-disc, is preferred in laboratory settings, as they require smaller test specimens and can determine coefficient of friction. In this study, we systematically compare the differences of Taber wear and ball-on disc by evaluating with an electrolessly-deposited Ni-P alloy systems. The Taber wear shows purely abrasive wear, whereas the ball-on-disc test offers a complex blend of wear mechanisms, and provides the coefficient of …


Investigation Of Supersaturated Silver Alloys For High Hardness Jewelry Application, S Praiphruk, G Lothongkum, E Nisaratanaporn, B Lohwongwatana Dec 2013

Investigation Of Supersaturated Silver Alloys For High Hardness Jewelry Application, S Praiphruk, G Lothongkum, E Nisaratanaporn, B Lohwongwatana

Journal of Metals, Materials and Minerals

Sterling silver is one of the most widely used precious metal alloys in jewelry industry. 92.5 wt% silver content is the standard for sterling products, while 7.5 wt% is reserved for other alloying elements. Because the mechanical properties of pure silver such as yield strength and hardness are extremely low. In the bounds of 7.5 wt% solute addition, different approaches have been introduced in order to improve the properties of sterling silver. For example, to increase the hardness of the jewelry pieces, metallurgists introduced age hardening, cold working, and surface treatments. We reported on the trend of intrinsic hardness increase …


Fabrication Of Chitosan/Titanium Dioxide Composites Film For The Photocatalytic Degradation Of Dye, P Norranattrakul, K Siralertmukul, R Nuisin Dec 2013

Fabrication Of Chitosan/Titanium Dioxide Composites Film For The Photocatalytic Degradation Of Dye, P Norranattrakul, K Siralertmukul, R Nuisin

Journal of Metals, Materials and Minerals

The investigation of the chitosan film as a polymer matrix for titanium dioxide (TiO2) dispersion was carried out. Chitosantitanium dioxide composite films were prepared by solution casting, using Chitosan, TiO2, Arquad T50 HFP as surfactant. The mixture of 1.0 g chitosan in 100 mL acetic acid was prepared, subsequently with the addition of TiO2. The solution was then cast onto an acrylic mold and allowed to air-dry. The external morphology of the composite film revealed the high dispersion of TiO2 in the polymer matrix. Three types of crosslinking agent; glutaraldehyde, citric acid, and itaconic acid were studied. It was found …


Crystallization Of Carnallite From Kcl-Mgcl2 Brine Solutions By Solvent Evaporation Process And Its Structural And Mechanical Characterization, J Podder, S Gao, R W Evitts, Rw Besant, D Matthews Dec 2013

Crystallization Of Carnallite From Kcl-Mgcl2 Brine Solutions By Solvent Evaporation Process And Its Structural And Mechanical Characterization, J Podder, S Gao, R W Evitts, Rw Besant, D Matthews

Journal of Metals, Materials and Minerals

Carnallite crystals have been synthesized from brine solutions at room temperature (23C) by solvent evaporation growth technique to show the effect of the concentration of potassium chloride (KCl) and magnesium chloride (MgCl2) on the growth, structural and mechanical properties of the crystal. Transparent and pseudo-hexagonal shape carnallite crystals with the dimension of 4 5 2 mm to 16 13 3 mm were grown. The crystals were characterized by powder X-ray diffraction and the lattice parameters were found to be a = 9.598 b = 16.141and c = 22.519 space group: Pnna, Z: 12, ? = ? = ? = 90 …


Heat Treatment Of Steel Parts In Different Media, Sc Maidargi, V Rani Dec 2013

Heat Treatment Of Steel Parts In Different Media, Sc Maidargi, V Rani

Journal of Metals, Materials and Minerals

This study reports an investigation of the effect of different media (oil and polymer) on the properties of different grade steel parts. Steel parts after manufacture, will not have the desired properties like wear resistance, tensile strength, surface and core hardness. To attain these, heat treatment processes like Case Hardening (CH) or Through Hardening (TH) were carried out in sealed quench furnace and rotary furnace. The microstructure of the steel part influences the hardness of the same. The required microstructure is Fine Tempered Martensite (FTM) and the Quench media has a very important role in achieving this. Using different grades …


Influence Of Calcium Carbonate Nanoparticles On Mechanical Behavior Of Poly(Lactic Acid)/Poly(Butylene Succinate) Blend, N Hongsriphan, T Burirat, P Niratsungnern, S Trongteng Jul 2013

Influence Of Calcium Carbonate Nanoparticles On Mechanical Behavior Of Poly(Lactic Acid)/Poly(Butylene Succinate) Blend, N Hongsriphan, T Burirat, P Niratsungnern, S Trongteng

Journal of Metals, Materials and Minerals

PLA/PBS blends in various blend ratio (70:30, 50:50, and 30:70 wt%) containing calcium carbonate nanoparticles (nano-CaCO3) of 1 and 5 phr were prepared. Tensile tests with 3 strain rates and Izod impact test were carried out in order to investigate the influence of CaCO3 nanoparticles on mechanical behavior of nanocomposites under different deformation rates. Morphology and compatibility of nanocomposites were studied using SEM and DSC. It is found that PBS/PLA 50/50 wt% blends exhibited the highest percentage of elongation at break due to co-continuous phases as seen in SEM. CaCO3 nanoparticles were dispersed uniformly in polymer matrix although they showed …


Conversion Of Secondary Pulp And Paper Sludge To Glucose By Hydrothermal Treatment, N Chariyaprasertsin, Y Matsumura, T Charinpanitkul Jul 2013

Conversion Of Secondary Pulp And Paper Sludge To Glucose By Hydrothermal Treatment, N Chariyaprasertsin, Y Matsumura, T Charinpanitkul

Journal of Metals, Materials and Minerals

Secondary pulp/paper sludge is residue from water treatment process of the paper industry. Main components of secondary pulp/paper sludge are cellulose, hemicelluose, lignin and calcium carbonate (CaCO3). The cellulose and hemicellulose could be converted to glucose by hydrothermal treatment in a stainless steel tubular batch reactor. It was found that dried powder of secondary pulp/paper sludge with nominal size in a range of 595 to 840 m contains different content of CaCO3. Therefore, effect of CaCO3 content on glucose yields was examined under designated temperature of 200-260 C and treating time of 0-40 minutes. Identification and quantification of glucose and …


Chitosan Derivative-Based Hemostat: Irritation, Hypersensitivity And Absorbability Study, B Thavornyutikarn, W Kosorn, P Surattanawanich, U Wongparami, W Janvikul Jul 2013

Chitosan Derivative-Based Hemostat: Irritation, Hypersensitivity And Absorbability Study, B Thavornyutikarn, W Kosorn, P Surattanawanich, U Wongparami, W Janvikul

Journal of Metals, Materials and Minerals

The objective of this study was to evaluate the safety of a carboxymethylchitosan-based hemostatic prototype for internal use, in terms of irritation, hypersensitivity and absorbability. Skin irritation and delayed-type hypersensitivity tests of the prototype in humans (n=30) were assessed by a patch test method. The human skin sites were graded and photographed after patch removal at each time point using a 4-point (0-3+) grading scale of increasing irritation related to ISO 10993-10:2002(E) and a 6-point grading scale of increasing allergy related to International Contact Dermatitis Research Group (ICDRG). The results demonstrated that the chitosan derivative-based hemostat did not cause skin …


Characterization Of Diamond-Like Carbon (Dlc) Films Deposited By Filtered Cathodic Vacuum Arc Technique, N Konkhunthot, C Euaruksakul, P Photongkam, P Wongpanya Jul 2013

Characterization Of Diamond-Like Carbon (Dlc) Films Deposited By Filtered Cathodic Vacuum Arc Technique, N Konkhunthot, C Euaruksakul, P Photongkam, P Wongpanya

Journal of Metals, Materials and Minerals

Diamond-like carbon (DLC) films were prepared on AISI H13 hot-work tool steel substrates by filtered cathodic vacuum arc (FCVA) technique under variable substrate DC biasing. The atomic structures of the films were investigated by Raman spectroscopy, X-ray photoelectron spectroscopy, and near edge x-ray absorption fine structure spectroscopy. The Raman spectra revealed that when the magnitude of the bias voltage increased, the G peak was shifted toward lower wave numbers, and indicated that the sp3 content in the DLC films increased. The ratios between the sp3 and sp2 bonds in the films were verified by X-ray photoelectron spectroscopy, and the analyses …


Crystallization Behavior Of Pla In Pla/Nr Compared With Dynamic Vulcanized Pla/Nr, C Thongpin, S Klatsuwan, P Borkchaiyapoom, S Thongkamwong Jul 2013

Crystallization Behavior Of Pla In Pla/Nr Compared With Dynamic Vulcanized Pla/Nr, C Thongpin, S Klatsuwan, P Borkchaiyapoom, S Thongkamwong

Journal of Metals, Materials and Minerals

PLA has been an interesting biopolymer widely used in various applications. It has been widely known that crystallization of PLA is rather slow. After melt processing, crystallinity of PLA could be lost. The study of PLA added with fibers, particles or even nano-particles has been studied extensively. Nonetheless, the suffering in some mechanical characteristic such as toughness has been encountered. Our research was aimed to enhance toughness of PLA by melt blending NR, and dynamic vulcanized NR into PLA using an internal mixer. PLA:NR and PLA:NR vulcanizate with the ratio of 90:10, 80:20, 70:30, 60:40 and 50:50 were studied. Crystallization …


Dissolved Oxygen Sensor Film Using Ruthenium Polypyridine Complex As Luminophore, C Su-Ngam, Sh Thang, A Wongchaisuwat, L Meesuk Jul 2013

Dissolved Oxygen Sensor Film Using Ruthenium Polypyridine Complex As Luminophore, C Su-Ngam, Sh Thang, A Wongchaisuwat, L Meesuk

Journal of Metals, Materials and Minerals

Ruthenium polypyridine complex was synthesized by using RAFT process. The Ruthenium was immobilized in 2 silicone matrices, polydimethylsiloxane(PDMS) and KE 200 (silicone elastomer base)/CX200 (curing agent). KE 200/CX200 is the alcohols curing type silicone. Both sensor films showed absorption peak at 460 nm and luminescence peak at 610 nm. The KE200/CX200 film gave linear response to dissolved oxygen up to 80% O2 (18 ppm) follow Stern-Volmer equation with R2 of 0.990. The measured luminescence intensity decreased with increasing dissolved oxygen water temperature from 25 to 70c. After being irradiated with 460 nm light source for 3 hrs, the sensor film …


Low Temperature Chemical Precipitation And Characterization Of Ceria Based Ceramic Composite Oxide Materials, D Radhika, A Samson Nesaraj Jul 2013

Low Temperature Chemical Precipitation And Characterization Of Ceria Based Ceramic Composite Oxide Materials, D Radhika, A Samson Nesaraj

Journal of Metals, Materials and Minerals

Ceria based ceramic composite oxide materials such as Ce0.9Gd0.1O2-δ -Ce0.9Y0.1O2-δ and Ce0.8Gd0.2O2-δCe0.8Y0.2O2-δ were prepared by a simple chemical precipitation method for application in low temperature solid oxide fuel cells (LTSOFCs) as electrolytes. The precursor materials used in this synthesis were cerium nitrate hexahydrate, gadolinium nitrate and yttrium nitrate (as basic materials), sodium hydroxide (as precipitator material) and PVA (as surfactant). A mixture of metal hydroxides was formed when the aqueous mixture of basic materials mixed with the aqueous precipitant solution in proper stoichiometric composition. The resultant hydroxide mixture was washed with ethanol and water mixture (1:9 volume ratio) to remove …


Halogenated Sorbitol Derivatives Using As Nucleating Agent And Their Effect On Orientation Of Polypropylene Fiber, T Sutthatang, S Wangsoub Jul 2013

Halogenated Sorbitol Derivatives Using As Nucleating Agent And Their Effect On Orientation Of Polypropylene Fiber, T Sutthatang, S Wangsoub

Journal of Metals, Materials and Minerals

In this work, two halogenated derivatives of benzylidene sorbitol were synthesized by reacting D-sorbitol with an aromatic aldehyde in the present of an acid catalyst. ie.chloro and bromo derivatives for using as nucleating agent for polypropylene. For chloro derivative, different positions of substituent (ortho, meta and para) were also synthesised. SEM and TEM micrographs of gel extracted from organic solvent revealed long fibril network of chloro and bromo substitutes which their diameters are in the range of about 10-200 nm. Small amount (0.1-1%wt) of these materials was blended with isotactic polypropylene (iPP) by two roll mill machine and the mixture …


Parameters Optimization Of Copper Wire Bonding On Thin Small Outline Package, S Srikamonsirisak, U Tantinuchawong, Y Satirakul Jul 2013

Parameters Optimization Of Copper Wire Bonding On Thin Small Outline Package, S Srikamonsirisak, U Tantinuchawong, Y Satirakul

Journal of Metals, Materials and Minerals

With significant rising of Au price, there is growing demand to implement Cu wire bonding as an alternative method for Au wire bonding. However, there are several challenges to overcome because Cu is easily oxidized and its property is harder than Au. The oxidation deteriorates bondability and bond reliability, while the greater wire hardness leads to the more severe wire bonding parameters (higher force, higher power, higher temperature), which results in physical damage of the bond pad and underlying layers. This paper reveals wire bonding parameters optimization in order to implement Cu wire bonding in high volume production environment with …


Titanium Dioxide Nanostructures Synthesized By Sonochemical Hydrothermal Process, N Wongpisutpaisan, C Kahattha, N Vittayakorn, A Ruangphanit, W Pecharapa Jul 2013

Titanium Dioxide Nanostructures Synthesized By Sonochemical Hydrothermal Process, N Wongpisutpaisan, C Kahattha, N Vittayakorn, A Ruangphanit, W Pecharapa

Journal of Metals, Materials and Minerals

Titanium dioxide particles were prepared by sonochemicalhydrothermal process from a precursor of titanium isopropoxide in the presence of polyvinyl alcohol aqueous solution. Sonication of the precursor was conducted using sonic horn operated at 20 kHz until the completely precipitated product was reached. As-obtained intermediate products were then loaded into a Teflon-lined stainless steel autoclave for hydrothermal process with10M NaOH aqueous solution and heated under different temperature 80-120C. The synthesized products were characterized of structural properties and surface morphology by X-ray diffraction spectroscopy and field emission scanning electron microscope. The results show that prepared samples have a good crystallinity and the …


Application Of Para Rubber Latex Mixed With Organic Dyes As Printing Ink For Biodegradable Plastic Film, T Techochaingam, S Netpradit, K Tanprasert, P Boochathum Jul 2013

Application Of Para Rubber Latex Mixed With Organic Dyes As Printing Ink For Biodegradable Plastic Film, T Techochaingam, S Netpradit, K Tanprasert, P Boochathum

Journal of Metals, Materials and Minerals

content of 35.9% and 41.2%, which had the viscosity of 9.52 seconds and drying time of around 5 minutes. The viscosity of Para rubber latex with solid content of 59.0% and 61.4% was very high; thus, resulted in coagulation. Then modified rubber latex CNR with solid content of 16.5%, 19.2%, 26.8% and 28.2%, which had the viscosity around 8.30 seconds and drying time of around 5 minutes. Dye solution was prepared by adding 1 part of dye to 1 part of water (w/w). The formulation of ink that yielded the highest optical density of 1.43 was 8.4 g dye solution …


Macrostructure Modeling Of Al-20 % Sn Alloy, P Padhi, Ak Sahoo, S Kar Jul 2013

Macrostructure Modeling Of Al-20 % Sn Alloy, P Padhi, Ak Sahoo, S Kar

Journal of Metals, Materials and Minerals

In metallic alloys, the formation of macrostructure involves different length and time scales. The macrostructure strongly influences the mechanical properties of the materials. Modeling of macrostructure provides valuable insights for tailoring of the structure. In the present study simulation of macrostructure in Al-20Sn has been carried out. Expression for nucleation rate and growth rate were tuned to get a match with the experimentally observed macrostructure. The study incorporates the motion of grains due to Brownian motion. Incorporation of Brownian motion resulted in more uniform distribution locally, which has been experimentally observed. Both simulation and macrograph showed few columnar grains and …


Upconversion Luminescence Of Yttrium Oxysulfide Co-Doped With Rare Earth Elements, U Injarean, P Pichestapong, T Ruangsiritanyakul, S Tayaniphant Jul 2013

Upconversion Luminescence Of Yttrium Oxysulfide Co-Doped With Rare Earth Elements, U Injarean, P Pichestapong, T Ruangsiritanyakul, S Tayaniphant

Journal of Metals, Materials and Minerals

Rare earth ions doped upconversion phosphors have been used in many applications such as infrared laser detecting, anti-counterfeit protection and solid state display. In this study, yttrium oxysulfide (Y2O2S) compounds co-doped with rare earth elements, ytterbium (Yb), and one of the following elements, erbium (Er), thulium (Tm), europium (Eu) or holmium (Ho) were synthesized from doped rare earth oxides using sulfide fusion method with pelletization pretreatment. The doping was carried out with the mixing of yttrium nitrate and rare earth nitrate solutions to obtain homogeneous mixture. The mixed nitrate solution was precipitated with oxalic acid and calcined to doped oxide …