E-Mail Alert

Add your e-mail address to receive forthcoming issues of this journal:

Journal Browser

Journal Browser

Special Issue "Selected Papers from ICETI2014"

Quicklinks

A special issue of Materials (ISSN 1996-1944).

Deadline for manuscript submissions: closed (30 August 2015)

Special Issue Editors

Guest Editor
Prof. Dr. Wen-Hsiang Hsieh (Website)

Department of Automation Engineering, National Formosa University, Huwei, Yunlin 632, Taiwan
Interests: engineering applications of materials; mechatronics; automatic machinery
Guest Editor
Prof. Dr. Gow-Yi Tzou (Website)

Department of Mechanical and Automation Engineering Kao Yuan University
Interests: materials processing; metal forming; precision manufacturing

Special Issue Information

Dear Colleagues,

The Second International Conference on Engineering and Technology Innovation 2012 (ICETI2012), held in Kaohsiung in November 2012, was an outstanding success. The third international conference(ICETI2014) will follow up the success of ICETI2012 by bringing together researchers and application developers from different areas focusing on unifying themes.

This ICETI2014 conference covers a wide range of fields in science and engineering innovation and aims to bring together engineering technology expertise. The professional from the industry, academia and government to discourse on research and development, professional practice, business and management in the science and engineering fields are welcome to the ICETI2014. This conference enables interdisciplinary collaboration between science and engineering technologists in the academic and industrial fields as well as networking internationally. During the conference, there should be substantial time for presentation and discussion. In addition, poster sessions and exhibitions offer ample opportunity for information exchange among delegates and participants, especially for those who are looking for new opportunity between presenters and participants. Attendees will find various activities useful in bringing together a diverse group of engineers and technologists from across disciplines for the generation of new ideas, collaboration potential and business opportunities.

Kenting is the most popular area for tourist, at the southernmost tip of Taiwan. The unique regional features here include coral reefs, solitary mountains, ponds, sand dunes, and tropical forests. The seaside in Kenting is a good place for recreation and swimming. In November, the temperature around Kenting is between 22 to 28 ℃. Therefore, Kenting is a perfect location for a relaxing stroll before or after your congress day.

Prof. Dr. Wen-Hsiang Hsieh
Prof. Dr. Gow-Yi Tzou
Guest Editors

Submission

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. Papers will be published continuously (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are refereed through a peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Materials is an international peer-reviewed Open Access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 1400 CHF (Swiss Francs).

Published Papers (15 papers)

View options order results:
result details:
Displaying articles 1-15
Export citation of selected articles as:

Research

Open AccessArticle Polypropylene/Short Glass Fibers Composites: Effects of Coupling Agents on Mechanical Properties, Thermal Behaviors, and Morphology
Materials 2015, 8(12), 8279-8291; doi:10.3390/ma8125451
Received: 13 October 2015 / Revised: 16 November 2015 / Accepted: 20 November 2015 / Published: 2 December 2015
Cited by 2 | PDF Full-text (8315 KB) | HTML Full-text | XML Full-text
Abstract
This study uses the melt compounding method to produce polypropylene (PP)/short glass fibers (SGF) composites. PP serves as matrix while SGF serves as reinforcement. Two coupling agents, maleic anhydride grafted polypropylene, (PP-g-MA) and maleic anhydride grafted styrene-ethylene-butylene-styrene block copolymer (SEBS-g-MA) are incorporated [...] Read more.
This study uses the melt compounding method to produce polypropylene (PP)/short glass fibers (SGF) composites. PP serves as matrix while SGF serves as reinforcement. Two coupling agents, maleic anhydride grafted polypropylene, (PP-g-MA) and maleic anhydride grafted styrene-ethylene-butylene-styrene block copolymer (SEBS-g-MA) are incorporated in the PP/SGF composites during the compounding process, in order to improve the interfacial adhesion and create diverse desired properties of the composites. According to the mechanical property evaluations, increasing PP-g-MA as a coupling agent provides the composites with higher tensile, flexural, and impact properties. In contrast, increasing SEBS-g-MA as a coupling agent provides the composites with decreasing tensile and flexural strengths, but also increasing impact strength. The DSC results indicate that using either PP-g-MA or SEBS-g-MA as the coupling agent increases the crystallization temperature. However, the melting temperature of PP barely changes. The spherulitic morphology results show that PP has a smaller spherulite size when it is processed with PP-g-MA or SEBS-g-MA as the coupling agent. The SEM results indicate that SGF is evenly distributed in PP matrices, but there are distinct voids between these two materials, indicating a poor interfacial adhesion. After PP-g-MA or SEBS-g-MA is incorporated, SGF can be encapsulated by PP, and the voids between them are fewer and indistinctive. This indicates that the coupling agents can effectively improve the interfacial compatibility between PP and SGF, and as a result improves the diverse properties of PP/SGF composites. Full article
(This article belongs to the Special Issue Selected Papers from ICETI2014)
Open AccessArticle Magnetic Control of Fe3O4 Nanomaterial for Fat Ablation in Microchannel
Materials 2015, 8(11), 7813-7820; doi:10.3390/ma8115429
Received: 14 October 2015 / Revised: 12 November 2015 / Accepted: 13 November 2015 / Published: 19 November 2015
PDF Full-text (3836 KB) | HTML Full-text | XML Full-text
Abstract
In this study, surface modification of iron (II, III) oxide Fe3O4 nanoparticles by oleic acid (OA) coating is investigated for the microablation of fat in a microchannel. The nanoparticles are synthesized by the co-precipitation method and then dispersed in [...] Read more.
In this study, surface modification of iron (II, III) oxide Fe3O4 nanoparticles by oleic acid (OA) coating is investigated for the microablation of fat in a microchannel. The nanoparticles are synthesized by the co-precipitation method and then dispersed in organic solvent prior to mixing with the OA. The magnetization, agglomeration, and particle size distribution properties of the OA-coated Fe3O4 nanoparticles are characterized. The surface modification of the Fe3O4 nanoparticles reveals that upon injection into a microchannel, the lipophilicity of the OA coating influences the movement of the nanoparticles across an oil-phase barrier. The motion of the nanoparticles is controlled using an AC magnetic field to induce magnetic torque and a static gradient field to control linear translation. The fat microablation process in a microchannel is demonstrated using an oscillating driving field of less than 1200 Am−1. Full article
(This article belongs to the Special Issue Selected Papers from ICETI2014)
Open AccessArticle Study on Platinum Coating Depth in Focused Ion Beam Diamond Cutting Tool Milling and Methods for Removing Platinum Layer
Materials 2015, 8(9), 6498-6507; doi:10.3390/ma8095317
Received: 29 July 2015 / Revised: 3 September 2015 / Accepted: 15 September 2015 / Published: 22 September 2015
PDF Full-text (1603 KB) | HTML Full-text | XML Full-text
Abstract
In recent years, nanomachining has attracted increasing attention in advanced manufacturing science and technologies as a value-added processes to control material structures, components, devices, and nanoscale systems. To make sub-micro patterns on these products, micro/nanoscale single-crystal diamond cutting tools are essential. Popular [...] Read more.
In recent years, nanomachining has attracted increasing attention in advanced manufacturing science and technologies as a value-added processes to control material structures, components, devices, and nanoscale systems. To make sub-micro patterns on these products, micro/nanoscale single-crystal diamond cutting tools are essential. Popular non-contact methods for the macro/micro processing of diamond composites are pulsed laser ablation (PLA) and electric discharge machining (EDM). However, for manufacturing nanoscale diamond tools, these machining methods are not appropriate. Despite diamond’s extreme physical properties, diamond can be micro/nano machined relatively easily using a focused ion beam (FIB) technique. In the FIB milling process, the surface properties of the diamond cutting tool is affected by the amorphous damage layer caused by the FIB gallium ion collision and implantation and these influence the diamond cutting tool edge sharpness and increase the processing procedures. To protect the diamond substrate, a protection layer—platinum (Pt) coating is essential in diamond FIB milling. In this study, the depth of Pt coating layer which could decrease process-induced damage during FIB fabrication is investigated, along with methods for removing the Pt coating layer on diamond tools. The optimum Pt coating depth has been confirmed, which is very important for maintaining cutting tool edge sharpness and decreasing processing procedures. The ultra-precision grinding method and etching with aqua regia method have been investigated for removing the Pt coating layer. Experimental results show that when the diamond cutting tool width is bigger than 500 nm, ultra-precision grinding method is appropriate for removing Pt coating layer on diamond tool. However, the ultra-precision grinding method is not recommended for removing the Pt coating layer when the cutting tool width is smaller than 500 nm, because the possibility that the diamond cutting tool is damaged by the grinding process will be increased. Despite the etching method requiring more procedures to remove the Pt coating layer after FIB milling, it is a feasible method for diamond tools with under 500 nm width. Full article
(This article belongs to the Special Issue Selected Papers from ICETI2014)
Figures

Open AccessArticle Characterization of Platinum Nanoparticles Deposited on Functionalized Graphene Sheets
Materials 2015, 8(9), 6484-6497; doi:10.3390/ma8095318
Received: 18 August 2015 / Revised: 11 September 2015 / Accepted: 17 September 2015 / Published: 21 September 2015
PDF Full-text (3370 KB) | HTML Full-text | XML Full-text
Abstract
Due to its special electronic and ballistic transport properties, graphene has attracted much interest from researchers. In this study, platinum (Pt) nanoparticles were deposited on oxidized graphene sheets (cG). The graphene sheets were applied to overcome the corrosion problems of carbon black [...] Read more.
Due to its special electronic and ballistic transport properties, graphene has attracted much interest from researchers. In this study, platinum (Pt) nanoparticles were deposited on oxidized graphene sheets (cG). The graphene sheets were applied to overcome the corrosion problems of carbon black at operating conditions of proton exchange membrane fuel cells. To enhance the interfacial interactions between the graphene sheets and the Pt nanoparticles, the oxygen-containing functional groups were introduced onto the surface of graphene sheets. The results showed the Pt nanoparticles were uniformly dispersed on the surface of graphene sheets with a mean Pt particle size of 2.08 nm. The Pt nanoparticles deposited on graphene sheets exhibited better crystallinity and higher oxygen resistance. The metal Pt was the predominant Pt chemical state on Pt/cG (60.4%). The results from the cyclic voltammetry analysis showed the value of the electrochemical surface area (ECSA) was 88 m2/g (Pt/cG), much higher than that of Pt/C (46 m2/g). The long-term test illustrated the degradation in ECSA exhibited the order of Pt/C (33%) > Pt/cG (7%). The values of the utilization efficiency were calculated to be 64% for Pt/cG and 32% for Pt/C. Full article
(This article belongs to the Special Issue Selected Papers from ICETI2014)
Open AccessArticle Trap Exploration in Amorphous Boron-Doped ZnO Films
Materials 2015, 8(9), 5795-5805; doi:10.3390/ma8095276
Received: 28 May 2015 / Accepted: 25 August 2015 / Published: 31 August 2015
PDF Full-text (1146 KB) | HTML Full-text | XML Full-text
Abstract
This paper addresses the trap exploration in amorphous boron-doped ZnO (ZnO:B) films using an asymmetric structure of metal-oxide-metal. In this work, the structure of Ni/ZnO:B/TaN is adopted and the ZnO:B film is deposited by RF magnetron sputtering. The as-deposited ZnO:B film is [...] Read more.
This paper addresses the trap exploration in amorphous boron-doped ZnO (ZnO:B) films using an asymmetric structure of metal-oxide-metal. In this work, the structure of Ni/ZnO:B/TaN is adopted and the ZnO:B film is deposited by RF magnetron sputtering. The as-deposited ZnO:B film is amorphous and becomes polycrystalline when annealing temperature is above 500 °C. According to the analysis of conduction mechanism in the as-deposited ZnO:B devices, Ohmic conduction is obtained at positive bias voltage because of the Ohmic contact at the TaN/ZnO:B interface. Meanwhile, hopping conduction is obtained at negative bias voltage due to the defective traps in ZnO:B in which the trap energy level is lower than the energy barrier at the Ni/ZnO:B interface. In the hopping conduction, the temperature dependence of I-V characteristics reveals that the higher the temperature, the lower the current. This suggests that no single-level traps, but only multiple-level traps, exist in the amorphous ZnO:B films. Accordingly, the trap energy levels (0.46–0.64 eV) and trap spacing (1.1 nm) in these multiple-level traps are extracted. Full article
(This article belongs to the Special Issue Selected Papers from ICETI2014)
Open AccessArticle Development of Equivalent Material Properties of Microbump for Simulating Chip Stacking Packaging
Materials 2015, 8(8), 5121-5137; doi:10.3390/ma8085121
Received: 15 June 2015 / Revised: 24 July 2015 / Accepted: 4 August 2015 / Published: 7 August 2015
Cited by 1 | PDF Full-text (954 KB) | HTML Full-text | XML Full-text
Abstract
three-dimensional integrated circuit (3D-IC) structure with a significant scale mismatch causes difficulty in analytic model construction. This paper proposes a simulation technique to introduce an equivalent material composed of microbumps and their surrounding wafer level underfill (WLUF). The mechanical properties of this [...] Read more.
three-dimensional integrated circuit (3D-IC) structure with a significant scale mismatch causes difficulty in analytic model construction. This paper proposes a simulation technique to introduce an equivalent material composed of microbumps and their surrounding wafer level underfill (WLUF). The mechanical properties of this equivalent material, including Young’s modulus (E), Poisson’s ratio, shear modulus, and coefficient of thermal expansion (CTE), are directly obtained by applying either a tensile load or a constant displacement, and by increasing the temperature during simulations, respectively. Analytic results indicate that at least eight microbumps at the outermost region of the chip stacking structure need to be considered as an accurate stress/strain contour in the concerned region. In addition, a factorial experimental design with analysis of variance is proposed to optimize chip stacking structure reliability with four factors: chip thickness, substrate thickness, CTE, and E-value. Analytic results show that the most significant factor is CTE of WLUF. This factor affects microbump reliability and structural warpage under a temperature cycling load and high-temperature bonding process. WLUF with low CTE and high E-value are recommended to enhance the assembly reliability of the 3D-IC architecture. Full article
(This article belongs to the Special Issue Selected Papers from ICETI2014)
Open AccessArticle Study on Welding Mechanism Based on Modification of Polypropylene for Improving the Laser Transmission Weldability to PA66
Materials 2015, 8(8), 4961-4977; doi:10.3390/ma8084961
Received: 25 May 2015 / Accepted: 30 July 2015 / Published: 4 August 2015
Cited by 1 | PDF Full-text (2402 KB) | HTML Full-text | XML Full-text
Abstract
Polypropylene and PA66 are widely used in our daily life, but they cannot be welded by laser transmission welding (LTW) because of polar differences and poor compatibility. In this paper, grafting modification technology is used to improve the welding performance between polypropylene [...] Read more.
Polypropylene and PA66 are widely used in our daily life, but they cannot be welded by laser transmission welding (LTW) because of polar differences and poor compatibility. In this paper, grafting modification technology is used to improve the welding performance between polypropylene and PA66. Firstly, the strong reactive and polar maleic-anhydride (MAH) is grafted to polypropylene and infrared spectrometer is used to prove that MAH has been grafted to polypropylene. At the same time, the mechanical and thermal properties of the graft modified polypropylene (TGMPP) are tested. The results prove that the grafting modification has little influence on them. Also, the optical properties of TGMPP are measured. Then, the high welding strength between TGMPP and PA66 is found and the mechanism of the weldability is researched, which shows that there are two reasons for the high welding strength. By observing the micro morphology of the welding zone, one reason found is that the modification of polypropylene can improve the compatibility between polypropylene and PA66 and make them easy to diffuse mutually, which causes many locking structures formed in the welding region. The other reason is that there are chemical reactions between TGMPP and PA66 proved by the X-ray photoelectron spectrometer. Full article
(This article belongs to the Special Issue Selected Papers from ICETI2014)
Open AccessArticle Preparation and Characterization of Surface Photocatalytic Activity with NiO/TiO2 Nanocomposite Structure
Materials 2015, 8(7), 4273-4286; doi:10.3390/ma8074273
Received: 24 May 2015 / Revised: 26 June 2015 / Accepted: 3 July 2015 / Published: 13 July 2015
Cited by 4 | PDF Full-text (1120 KB) | HTML Full-text | XML Full-text
Abstract
This study achieved a nanocomposite structure of nickel oxide (NiO)/titanium dioxide (TiO2) heterojunction on a TiO2 film surface. The photocatalytic activity of this structure evaluated by decomposing methylene blue (MB) solution was strongly correlated to the conductive behavior of [...] Read more.
This study achieved a nanocomposite structure of nickel oxide (NiO)/titanium dioxide (TiO2) heterojunction on a TiO2 film surface. The photocatalytic activity of this structure evaluated by decomposing methylene blue (MB) solution was strongly correlated to the conductive behavior of the NiO film. A p-type NiO film of high concentration in contact with the native n-type TiO2 film, which resulted in a strong inner electrical field to effectively separate the photogenerated electron-hole pairs, exhibited a much better photocatalytic activity than the controlled TiO2 film. In addition, the photocatalytic activity of the NiO/TiO2 nanocomposite structure was enhanced as the thickness of the p-NiO film decreased, which was beneficial for the migration of the photogenerated carriers to the structural surface. Full article
(This article belongs to the Special Issue Selected Papers from ICETI2014)
Open AccessArticle The Modification of a Tetrafunctional Epoxy and Its Curing Reaction
Materials 2015, 8(6), 3671-3684; doi:10.3390/ma8063671
Received: 25 January 2015 / Revised: 8 June 2015 / Accepted: 8 June 2015 / Published: 18 June 2015
PDF Full-text (1584 KB) | HTML Full-text | XML Full-text
Abstract
Recent experimental results showed that the Tg of cured resin scarcely decreased and the impact strength of resins increased by over 50% when a tetrafunctional epoxy named N,N,N',N'-tetraglycidyl-4,4'-diaminodiphenyl ether (TGDDE) was introduced to an [...] Read more.
Recent experimental results showed that the Tg of cured resin scarcely decreased and the impact strength of resins increased by over 50% when a tetrafunctional epoxy named N,N,N',N'-tetraglycidyl-4,4'-diaminodiphenyl ether (TGDDE) was introduced to an appropriate flexible chain from a dimer fatty acid (DFA). In order to understand the reason for this phenomenon, the modification and the chemical structure of the prepolymer together with the curing reaction and the viscoelasticity of the cured resins were studied in detail in the present work. The results indicated that the modification would help the prepolymer improve its molecular mobility. As a result, the resins could be further cured, resulting in the cross-linking density increasing. This is because the curing efficiency was increased, but the tetrafunctional epoxy was not cured completely due to its large steric hindrance. Moreover, the flexibility of some parts of the networks was improved, which was beneficial for the toughness of the cured resins. Therefore, the toughness of the tetrafunctional resin was improved with little influence on the thermal properties when the epoxies were modified with an appropriate content of DFA. Full article
(This article belongs to the Special Issue Selected Papers from ICETI2014)
Open AccessArticle Preparation of Advanced Carbon Anode Materials from Mesocarbon Microbeads for Use in High C-Rate Lithium Ion Batteries
Materials 2015, 8(6), 3550-3561; doi:10.3390/ma8063550
Received: 13 May 2015 / Revised: 1 June 2015 / Accepted: 3 June 2015 / Published: 17 June 2015
Cited by 3 | PDF Full-text (2259 KB) | HTML Full-text | XML Full-text
Abstract
Mesophase soft carbon (MSC) and mesophase graphite (SMG), for use in comparative studies of high C-rate Lithium Ion Battery (LIB) anodes, were made by heating mesocarbon microbeads (MCMB) at 1300 °C and 3000 °C; respectively. The crystalline structures and morphologies of the [...] Read more.
Mesophase soft carbon (MSC) and mesophase graphite (SMG), for use in comparative studies of high C-rate Lithium Ion Battery (LIB) anodes, were made by heating mesocarbon microbeads (MCMB) at 1300 °C and 3000 °C; respectively. The crystalline structures and morphologies of the MSC, SMG, and commercial hard carbon (HC) were investigated by X-ray diffraction, transmission electron microscopy, scanning electron microscopy, and Raman spectroscopy. Additionally, their electrochemical properties, when used as anode materials in LIBs, were also investigated. The results show that MSC has a superior charging rate capability compared to SMG and HC. This is attributed to MSC having a more extensive interlayer spacing than SMG, and a greater number of favorably-oriented pathways when compared to HC. Full article
(This article belongs to the Special Issue Selected Papers from ICETI2014)
Open AccessArticle The Microstructural Evolution and Mechanical Properties of Zr-Based Metallic Glass under Different Strain Rate Compressions
Materials 2015, 8(4), 1831-1840; doi:10.3390/ma8041831
Received: 30 January 2015 / Revised: 23 March 2015 / Accepted: 10 April 2015 / Published: 16 April 2015
Cited by 2 | PDF Full-text (1425 KB) | HTML Full-text | XML Full-text
Abstract
In this study, the high strain rate deformation behavior and the microstructure evolution of Zr-Cu-Al-Ni metallic glasses under various strain rates were investigated. The influence of strain and strain rate on the mechanical properties and fracture behavior, as well as microstructural properties [...] Read more.
In this study, the high strain rate deformation behavior and the microstructure evolution of Zr-Cu-Al-Ni metallic glasses under various strain rates were investigated. The influence of strain and strain rate on the mechanical properties and fracture behavior, as well as microstructural properties was also investigated. Before mechanical testing, the structure and thermal stability of the Zr-Cu-Al-Ni metallic glasses were studied with X-ray diffraction (XRD) and differential scanning calorimeter. The mechanical property experiments and microstructural observations of Zr-Cu-Al-Ni metallic glasses under different strain rates ranging from 10−3 to 5.1 × 103 s−1 and at temperatures of 25 °C were investigated using compressive split-Hopkinson bar (SHPB) and an MTS tester. An in situ transmission electron microscope (TEM) nanoindenter was used to carry out compression tests and investigate the deformation behavior arising at nanopillars of the Zr-based metallic glass. The formation and interaction of shear band during the plastic deformation were investigated. Moreover, it was clearly apparent that the mechanical strength and ductility could be enhanced by impeding the penetration of shear bands with reinforced particles. Full article
(This article belongs to the Special Issue Selected Papers from ICETI2014)
Open AccessArticle Preparation and Tribological Study of Biodegradable Lubrication Films on Si Substrate
Materials 2015, 8(4), 1738-1751; doi:10.3390/ma8041738
Received: 30 January 2015 / Revised: 23 March 2015 / Accepted: 7 April 2015 / Published: 14 April 2015
Cited by 3 | PDF Full-text (3797 KB) | HTML Full-text | XML Full-text
Abstract
A novel method for preparing eco-biodegradable lubricant based on hydroxypropyl methylcellulose (HPMC) via hydration process is demonstrated. The smooth and homogeneous HPMC coating has a uniform thickness (~35 μm). It has been demonstrated that the preparation parameters play a critical role in [...] Read more.
A novel method for preparing eco-biodegradable lubricant based on hydroxypropyl methylcellulose (HPMC) via hydration process is demonstrated. The smooth and homogeneous HPMC coating has a uniform thickness (~35 μm). It has been demonstrated that the preparation parameters play a critical role in controlling the lubricating behavior of the coating; in addition, excess HPMC and water concentration suppress the tribology properties. Nevertheless, a remarkable friction-reduction and anti-wear performance has been obtained. Impressively, the preparation parameter of 5% HPMC + 30 mL water significantly improves lubricant performance and durability. A simple approach for the water-degradability evaluation of HPMC is proposed. Full article
(This article belongs to the Special Issue Selected Papers from ICETI2014)
Open AccessArticle Combustion Synthesis and Photoluminescence Properties of Red-Emitting CaAlSiN3:Eu2+ Phosphor for White-LEDs
Materials 2014, 7(12), 7828-7842; doi:10.3390/ma7127828
Received: 18 October 2014 / Revised: 19 November 2014 / Accepted: 27 November 2014 / Published: 5 December 2014
Cited by 3 | PDF Full-text (1174 KB) | HTML Full-text | XML Full-text
Abstract
A combustion synthesis method has been developed for synthesis of Eu2+ doped CaAlSiN3 phosphor and its photoluminescence properties were investigated. Ca, Al, Si, and Eu2O3 powders were used as the Ca, Al, Si and Eu sources. The [...] Read more.
A combustion synthesis method has been developed for synthesis of Eu2+ doped CaAlSiN3 phosphor and its photoluminescence properties were investigated. Ca, Al, Si, and Eu2O3 powders were used as the Ca, Al, Si and Eu sources. The addition of NaN3, NH4Cl and Si3N4 powders was found to increase significantly the product yield. These powders were mixed and pressed into a compact, which was then wrapped up with an igniting agent (i.e., Mg+Fe3O4). The compact was ignited by electrical heating under a N2 pressure of ≤1.0 MPa. Effects of these experimental parameters on the product yield were investigated and a reaction mechanism was proposed. The synthesized CaAlSiN3:Eu2+ phosphor absorbs light in the region of 200–600 nm and shows a broad band emission in the region of 500–800 nm due to the 4f65d1 → 4f7 transition of Eu2+. The sample doped with Eu2+ at the optimized molar ratio of 0.04 is efficiently excited by the blue light (460 nm) and generates emission peaking at ~650 nm with peak emission intensity ~106% of a commercially available phosphor, YAG:Ce3+(P46-Y3).The internal quantum efficiency of the synthesized phosphor was measured to be 71%, compared to 69% of the YAG:Ce3+ (P46-Y3). Full article
(This article belongs to the Special Issue Selected Papers from ICETI2014)
Open AccessArticle Engineering Properties and Correlation Analysis of Fiber Cementitious Materials
Materials 2014, 7(11), 7423-7435; doi:10.3390/ma7117423
Received: 1 September 2014 / Revised: 11 November 2014 / Accepted: 12 November 2014 / Published: 20 November 2014
Cited by 1 | PDF Full-text (499 KB) | HTML Full-text | XML Full-text
Abstract
This study focuses on the effect of the amount of silica fume addition and volume fraction of steel fiber on the engineering properties of cementitious materials. Test variables include dosage of silica fume (5% and 10%), water/cement ratio (0.35 and 0.55) and [...] Read more.
This study focuses on the effect of the amount of silica fume addition and volume fraction of steel fiber on the engineering properties of cementitious materials. Test variables include dosage of silica fume (5% and 10%), water/cement ratio (0.35 and 0.55) and steel fiber dosage (0.5%, 1.0% and 2.0%). The experimental results included: compressive strength, direct tensile strength, splitting tensile strength, surface abrasion and drop-weight test, which were collected to carry out the analysis of variance to realize the relevancy and significance between material parameters and those mechanical properties. Test results illustrate that the splitting tensile strength, direct tensile strength, strain capacity and ability of crack-arresting increase with increasing steel fiber and silica fume dosages, as well as the optimum mixture of the fiber cementitious materials is 5% replacement silica fume and 2% fiber dosage. In addition, the Pearson correlation coefficient was conducted to evaluate the influence of the material variables and corresponds to the experiment result. Full article
(This article belongs to the Special Issue Selected Papers from ICETI2014)
Open AccessArticle Conduction Mechanisms in Resistance Switching Memory Devices Using Transparent Boron Doped Zinc Oxide Films
Materials 2014, 7(11), 7339-7348; doi:10.3390/ma7117339
Received: 21 August 2014 / Revised: 23 October 2014 / Accepted: 7 November 2014 / Published: 12 November 2014
Cited by 8 | PDF Full-text (545 KB) | HTML Full-text | XML Full-text
Abstract
In this work, metal/oxide/metal capacitors were fabricated and investigated using transparent boron doped zinc oxide (ZnO:B) films for resistance switching memory applications. The optical band gap of ZnO:B films was determined to be about 3.26 eV and the average value of transmittance [...] Read more.
In this work, metal/oxide/metal capacitors were fabricated and investigated using transparent boron doped zinc oxide (ZnO:B) films for resistance switching memory applications. The optical band gap of ZnO:B films was determined to be about 3.26 eV and the average value of transmittance of ZnO:B films was about 91% in the visible light region. Experimental results indicated that the resistance switching in the W/ZnO:B/W structure is nonpolar. The resistance ratio of high resistance state (HRS) to low resistance state (LRS) is about of the order of 105 at room temperature. According to the temperature dependence of current-voltage characteristics, the conduction mechanism in ZnO:B films is dominated by hopping conduction and Ohmic conduction in HRS and LRS, respectively. Therefore, trap spacing (1.2 nm) and trap energy levels in ZnO:B films could be obtained. Full article
(This article belongs to the Special Issue Selected Papers from ICETI2014)

Journal Contact

MDPI AG
Materials Editorial Office
St. Alban-Anlage 66, 4052 Basel, Switzerland
materials@mdpi.com
Tel. +41 61 683 77 34
Fax: +41 61 302 89 18
Editorial Board
Contact Details Submit to Materials
Back to Top