bluuebunny/crossref_metadata_2025 huggingface dataset:
Using Goal Models Downstream
Authors: Horkoff Jennifer , Li Tong , Li Feng-Lin , Salnitri Mattia , Cardoso Evellin , Giorgini Paolo , Mylopoulos John
Published: April 2015

Goal models have proven useful for capturing, understanding, and communicating requirements during early stages of software development. However, the utility of goal models is greatly enhanced when they can be exploited during downstream stages of the requirements analysis process (e.g. requirements elaboration, validation, planning), and can be used as part of the entire system life cycle (e.g., architectural and behavioral process design, coding, testing, monitoring, adaptation, and evolution). In order to better understand the progress that has been made in integrating goal models with downstream system development, the authors ask: what approaches exist that map/integrate/transform goal models to later stage software artifacts? To answer this question, they conduct a systematic survey, producing a roadmap of work summarizing 243 publications. Results include a categorization of the “why?” and “how?” for each approach. Furthermore, they select the 50 most prominent publications, based on citation numbers, in order to perform an in-depth literature review. Findings show that there is a wide variety of proposals with a variety of proposed goal models and targets, covering multiple paradigms, motivated by a variety of purposes. The authors conclude that although much work has been done in this area, the work is fragmented, following multiple separate strands of goal-orientation, and is often still in early stages of maturity.
A Case Study Using the Analytic Hierarchy Process for IT Outsourcing Decision Making
Authors: Atkinson Mary Anne , Bayazit Ozden , Karpak Birsen
Published: April 2015

Decisions related to managing IT resources - which resources to keep in-house and which resources to outsource - are critical to business success. The goal of this paper is to show the usefulness of the Analytic Hierarchy Process (AHP) as a decision-making tool for IT sourcing decisions, based on an analysis of factors that recent literature found to be associated with IT sourcing risk. Although the AHP previously has been suggested for IT outsourcing decision making, this study is the first to consider evaluating the risks of offshore outsourcing, rural outsourcing, and in-sourcing IT processes by using the AHP. From the perspective of the expert decision maker, three IT sourcing strategies were evaluated with respect to 58 criteria. The case study example presented in this paper shows the effectiveness of the AHP to support management for this business decision. The authors' results show that a systematic approach to analyzing outsourcing can reduce the uncertainty and risk that is common in such decisions.
Synthesis and Mesophase of a Chiral Triphenylene-Based Discotic Liquid Crystal
Authors: Zhang Shuai Feng , Wang Jian Chuang , Zhang Chun Xiu , Wu Hao , Wang Yi Fei , Hong Feng , Hao Xing Tian , Zhang Ao , Pu Jia Ling
Published: April 2015

A chiral triphenylene-based compound 2-(2-octyloxy)-3,6,7,10,11-penta-pentyloxy triphenylene was synthesized by Mitsunobu reaction as shown in Fig.1. The structure of compound was determined by1HNMR and FT-IR spectrum and its mesomorphism was clarified by DSC and POM methods.
Inkjet Printing Enabling Silicon Photonics
Authors: Feng Xue , Qian Bo , Zhou Yan , Xie Yong Lin
Published: April 2015

In this paper, a concave on-chip silicon-based optical microcavity was designed and fabricated. The optical modes of the optical microcavity were measured by optical fiber system. The quality factor is demonstrated as high as 2850. The structure is an open access system, which can easily be combined with the inkjet print technology to have the applications in biosensors and on-chip light sources. Inkjet print technology is suggested as an important complementary method for micro-electro-mechanical systems.
Enhancement Effect of UV Light Emission by ZnO/Au Film on Flexible Structures
Authors: Yan Jia , Xiong Chen Lei , Qin Chen Jing , Li Xiu
Published: April 2015

We investigated the optical properties of ZnO/Au film structures fabricated by sputtering and spin coating. The PL intensity of the ZnO/Au was larger than that of a ZnO thin film by up to one orders of magnitude. The spectral dependence of the PL intensity was also well supported by the experimental reflectance spectra and the electric field distribution at the ZnO/Au interface.
Dip-Coating of Patterned Organic Semiconductor Films
Authors: Qin Meng Zhi , Wang Xiang Hua , Yuan Miao , Lv Shen Chen , Gu Xun
Published: April 2015

Dip-coating is a conventional solution processing technology to prepare large-area films at a low cost and with cheap facilities. For semiconductor film processing, crystal orientation and thickness uniformity are the primary factors that determine the film quality and its electrical performance. These requirements are readily satisfied with the dip-coating method because the film morphology can be effectively optimized by tuning the withdrawal speed. This work optimizes the withdrawal speed for the dip-coating of patterned semiconductor films of 400×500 mm2 as well as that for film dip-coating on the whole surfaces of the substrate. For both experiment, optimized electrical mobility is achieved at the same withdrawal speed, however, the random crystal orientation of the patterned films causes a remarkable decrease in device performance.
Novel Thieno[3,2-c]Pyridine Based Ir Complexes for Solution/Evaporation Hybrid OLED
Authors: Chao Teng Chih , Yeh Han Cheng , Chou Chin Hui , Chang Meng Hao , Tseng Mei Rurng
Published: April 2015

A series of novel thieno [3,2-c] pyridine based phosphorescent Ir complexes have been successfully synthesized and characterized. The HTL-free devices were fabricated on ITO with a multilayered structure of ITO/PEDOT:PSS(45 nm)/host (TCTA or NPB):dopant (10~15 nm)/TmPyPb/LiF/Al by solution/evaporation hybrid process and showed relatively high efficacies. The high efficacy enables these emitters to serve as promising candidates in fabricating high quality RGB displays. The monochromatic large-area of 40 x 32 mm2 OLEDs had also been demonstrated.
The Usage of Pet Kok is a Possibility of Reducing the Amount of Heavy Oil in the Rotary Kilns in the New Foundry of the New Ferronikel in Drenas
Authors: Gashi Zarife Bajraktari , Maksuti Rrahim , Murati Nagip
Published: April 2015

In this project we have represented the reduction of the ancillary heavy oil substance in the rotary kilns in the new foundry of the new Ferronickel in Drenas, with the use of the ancillary substance Pet Kok. The experimental and industrial research have been analyzed during the years 2008,2009,2010,2011,2012 and 2013. The chemical composition of heavy oil was analyzed in the INKOS Institute in Obiliq, while the composition of Pet Kok in the laboratory of the new foundry in the new Ferronickel in Drenas. The use of Pet Kok reduces the attachment of the substances in the rotary kilns walls, and it impacts the benefit of the calcines in a higher temperature and quality. The big amount of moisture of the Fe-Ni ore and the lack of an adequate dryer to reduce the moisture of the ore are two of the many factors of the large amount of ancillary substances in the rotary kilns. On 12.05.2011 pet kok has begun to be used in rotary kiln two, while in rotary kiln one pet kok has been used from 1.09.2012, the favorable impact of the use of pet kok in the technological process in the new foundry of the new Ferronickel in Drenas in the qualitative iron-nickel affected the reduction of the amount of heavy oil.
Cationic Catalyst as Latent Curing Agent for Epoxy Resin
Authors: Choi Ho Kyoung , Choi Bong Goo , Lee Yong Yoon , Na Jae Sik
Published: April 2015

1-Benzyl-3-methyl-imidazolium hexafluoroantimonate (BMH) was newly synthesized and characterized with FT-IR, 1H-NMR. We synthesized catalysts fulfill requirements for a rapid cure at a moderately elevated temperature in curing the epoxy resin for neat diglycidyl ether bisphenol A (DGBEA). The cure behavior of this resin was investigated at elevated temperature and cure temperature in the presence of 0.5, 1.0, 2.0 wt% of 1-benzyl-3-methyl-imidazolium hexafluoroantimonate (BMH) by mean of differential scanning calorimeter (DSC). Chemical conversion as function of temperature and amount of BMH (0.5, 1.0, 2.0 wt%) were determined from DSC. It was found that BMH were superior latent thermal catalyst for catinonic curing which have a good thermal stability.
Density Functional Theory Studies of Electronic Structures and Hyperfine Interactions of Muonium in Imidazole
Authors: Toh Pek Lan , Sulaiman Shukri , Mohamed Ibrahim Mohamed Ismail , Ang Lee Sin
Published: April 2015

We carried out ab initio electronic structure calculations in the frameworks of the Density Functional Theory (DFT) to study the electronic structures and hyperfine interaction of muonium (Mu) in imidazole (C3H4N2) and 1–methylimidazole (CH3C3H3N2). The local energy minima and hyperfine interactions of the Mu trapped at the three studies sites were determined by performing geometry optimization procedure. The results show the total energies for all three studied sites are close to one another. The Mu hyperfine interactions were also determined, with the corresponding values vary from 343.00 MHz to 471.28 MHz for the imidazole–Mu cluster, and from 380.21 MHz – 465.57 MHz to 475.93 MHz for the cluster of 1–methylimidazole–Mu, respectively.
Ellipsometry as Testing Method of Properties of Nano-Scale Films
Authors: Svitasheva Svetlana
Published: April 2015

Ellipsometry is power instrument for testing several properties of thin films. Advantage and attractiveness of these optical studies consist in that they are non-destructive and non-disturbing. High sensitivity to surface state allows us to monitoring properties of films beginning from atomic scale as in-situ and as ex situ. Ellipsometry give us information about film thickness, and film composition, and its surface morphology. From analysis of ellipsometric spectra it is possible get data about zone structure of semiconductor materials, such as energy of critical points, absorption edge location, and crystallinity. Speed of data acquisition is sufficient high to test dynamic of film growth. Ellipsometric measurements are quite simple but its interpretation requires special software. In this paper some possibilities of ellipsometric method are demonstrated in examples film polymorphism.
Increase the Microporosity and CO2 Adsorption of a Commercial Activated Carbon
Authors: Sreńscek Nazzal Joanna , Glonek Karolina , Młodzik Jacek , Narkiewicz Urszula , Morawski Antoni W. , Wrobel Rafal J. , Michalkiewicz Beata
Published: April 2015

Microporous carbons prepared from commercial activated carbon WG12 by KOH and/or ZnCl2 treatment were examined as adsorbents for CO2 capture. The micropore volume and specific surface area of the resulting carbons varied from 0.52 cm3/g (1374 m2/g) to 0.70 cm3/g (1800 m2/g), respectively. The obtained microporous carbon materials showed high CO2 adsorption capacities at 40 bar pressure reaching 16.4 mmol/g.
Effect of Post Deposition Annealing Process on the pH Sensitivity of Spin-Coated Titanium Dioxide Thin Film
Authors: Rahman Rohanieza Abdul , Zulkefle Muhammad Al Hadi , Hanim Abdullah Wan Fazlida , Herman Sukreen Hana
Published: April 2015

This paper presents an investigation on titanium dioxide (TiO2) thin film, which is used as sensing membrane for Extended-Gate Field Effect Transistor (EGFET) for pH sensing application. TiO2 thin films were deposited using sol-gel spin coating method on indium tin oxide (ITO) substrates. After the deposition, the thin films were annealed at 300 °C for 10 and 15 min, while another sample was annealed at 400 °C for 15 min. The sensitivity measurement was taken using the EGFET setup equipment with constant-current (100 μA) and constant-voltage (0.5 V) biasing interfacing circuit. TiO2 thin film as the pH-sensitive membrane and the working electrode was connected to a commercial metal-oxide semiconductor FET (MOSFET). The MOSFET then was connected to the interfacing circuit. The sensitivity of the TiO2 thin film towards pH buffer solution was measured by dipping the sensing membrane in pH4, pH7 and pH10 buffer solution. For comparison, a sample of bare-ITO was also tested to see its sensitivity. We found that the TiO2 thin film annealed at 400 °C for 15 min gave the highest sensitivity compared to other annealing conditions and also compared to the bare ITO substrate with the value of 44.30 mV/pH. This showed that TiO2 thin film can be used for pH sensing and the post-deposition treatment of the thin film can influence the sensing ability. We also measured the TiO2 thin films’ current – voltage (I-V) characteristics. Relating the I-V characteristic of the thin films and sensitivity, the sensing membrane with higher conductivity gave better sensitivity.
Preparation and Chemical Gas Sensing Behavior of ZnCo2O4 Nano-Crystals
Authors: Mariappan Chinnasamy Ramaraj
Published: April 2015

Spinel ZnCo2O4 nanosized powders were prepared by decomposing of the metal nitrate solutions at 100 °C. Structural properties of the sample were investigated by using powder X-ray diffraction (XRD), UV-visible and High resolution transmission electron microscopy (HR-TEM) techniques. Spinel crystal structure of the sample is confirmed by XRD analysis. The average crystallite size of the samples is found about 60 nm by Williamson-Hall analysis. The average grain size and crystalline nature of the samples is further confirmed by using the HR-TEM analysis. The band-gap energy is found to be 2.67 (±0.03) eV. Electrical properties were studied by two probe ac impedance spectroscopy. Dc conductivity is temperature dependent and found to obey the Arrhenius behaviour. The gas sensing behaviors were investigated by using dc and ac impedance measurement methods. It shows the promising gas sensing behavior for liquefied petroleum gas.
Acoustic-Absorbing Property of Puncture-Resisting Textile Wall Coverings Composites
Authors: Li Ting Ting , Lou Ching Wen , Lin Jia Horng
Published: April 2015

This study purposes to investigate acoustic absorbing and puncture resisting properties of wall covering composites with different number of layers, and then to construct prediction model of acoustic absorption coefficient. Puncture resistance linearly increases but maximum absorption coefficient shifts to lower frequency with number of layers.The acoustic absorbing property of wall covering composites presents porous acoustic-absorbing characteristic, and its prediction model correlates with critical frequency and maximum absorption coefficient. The resulting coverings have excellent puncture resistance and acoustic absorbing properties.
Hydroxyl Sodalite Having Combustion Gas Purification Function
Authors: Suzuki Kenzi , Li Chun Shan
Published: April 2015

Hydroxyl sodalite (Na8Al6Si6O24(OH)2) was investigated to develop a new ecofunctional material having removal performance for toxic substances including in combustion gas. Hydroxyl sodalite has nanometer-sized micro pore (β-cage) in the structure, and Cl- ions derived from HCl gas were fixed in the pores above 400 °C. The amount of Cl- ion fixed increased with increasing reaction temperature, and was the greatest, 7.3 wt% at 800 °C. In addition, it was found that Cu2+ ions were fixed in sodalite structure by substitution with Na+ ions by solid (hydroxyl sodalite) - gas (gaseous CuCl2) reaction. The substitution quantity increased with increasing reaction temperature. The amount of Cu2+ ion substituted was 10.5 wt% as CuO at 900 °C. From the above results, it was concluded that hydroxyl sodalite is an ecomaterial which is useful for combustion gas purification in the high temperatures.
Lamination of Glass Fiber Woven Fabrics and High Density Polyethylene/Clay Composition: Preparation, Tensile Properties, and Crystallization Properties
Authors: Lin Jia Horng , Chen Chih Kuang , Chen Wen Cheng , Tung Yu Chieh , Lou Ching Wen
Published: April 2015

In this study, high density polyethylene (HDPE) is reinforced by the combination of clay to form HDPE/clay composites by applying maleic anhydride grafted polyethylene (PE-g-MA) as a compatibilizer and a melt compounding method. The properties of composites are evaluated with a tensile strength test, a scanning electron microscope (SEM), and a differential scanning calorimetry (DSC). Next, such composites are laminated with glass fiber woven fabrics (GFW) to form HDPE/clay/GFW composites by using a thermal compression molding method. A tensile strength test and an SEM are used to measure the properties of the HDPE/clay/GFW composites. The test results show that the combination of clay in HDPE/clay composites does not provide their tensile strength with a distinct reinforcement. However, the dispersion of clay promotes the crystallization temperature of the HDPE/clay composites. In addition, using PE-g-MA as the compatibilizer results in a good adhesion of HDPE/clay composites to GFW, which in turn augments the tensile strength of the HDPE/clay/GFW composites.
Fracture of Carbon Fiber-Reinforced Plastic Composite for Light Weight Electric Vehicle under the Tensile Loading
Authors: Son In Seo , Shin Yu Jeong , Park Jong Bok , Son Gwan Pyo , Shin Dong Kil , Lee Jung Ju
Published: April 2015

Damage behavior of carbon fiber-reinforced plastic composite (CFRP) under the tensile loading was investigated. Four lay-up sequences were considered: [0o]4, [90o]4, [0o/90o]2, and [0o/45o/90o/-45o]. Experimental results showed that the specimen [0o]4 showed highest stiffness and strength followed by [0o/90o]2 , [0o/45o/90o/-45o], and [90o]4. The behavior was analyzed by finite element method. Progressive damage model Hashin’s damage initiation criteria and energy based damage evolution law were applied. It was shown that FEA results quite well agree with experimental results. The fracture strength was strongly dependent on the failure of the 0o directional ply.
Physical Properties of Geotextiles Reinforced by Recycled Kevlar Selvages
Authors: Lin Jia Horng , Li Jia Hsun , Hsieh Jing Chzi , Hsing Wen Hao , Lou Ching Wen
Published: April 2015

Kevlar fiber are artifical fibers that have been globally commonly used due to their attributes of a high modulus, a low elongation, an impact resistance, a chemical resistance, and thermostability. Therefore, this study proposes nonwoven geotextiles by corporating with recycled Kevlar unidirectoinal selvage with a low production cost, crimped polyester (PET) fibers, and low-melting-point PET (LPET) fibers. The content of LPET fiber is specified as 20 wt%, while the content of Kevlar fiber varies as 0 wt%, 5 wt%, 10 wt%, 15 wt%, and 20 wt%. The optimal tear strength of 195 N occurs with a content of Kevlar fiber being 20 wt%.
3D Numerical Simulation of Aluminum Foams Behavior in Large Deformation
Authors: Cherouat Abel , Zhu Shi Jie , Borouchaki Houman , Gong Xiao Lu
Published: April 2015

The compression characteristics of open-cell aluminum foams were experimentally and numerically investigated. It is found that the mechanical parameters, such as collapse stress and absorbed energy, are dependent on the porosity of aluminum foams material. During simulation of metal foam compression, the finite elements distort severely at the local regions with high gradient of physical field. The procedure integrates Explicit solver of Abaqus FEA, 3D Optiformmesher and Python script program transfer to execute step by step the incremental deformation of deformable body.
Mechanical and Morphological Properties of Poly(Methyl Methacrylate)/Ethylene-Octene Copolymer/Clay Composites
Authors: Wacharawichanant Sirirat
Published: April 2015

The effects of the montmorillonite clay surface modified with 25-30 wt% octadecylamine (clay) on mechanical and morphological properties of poly (methyl methacrylate) (PMMA)/ ethylene-octene copolymer (EOC)/clay composites were investigated. The composites of blends of PMMA/EOC with clay were prepared by melt mixing in an internal mixer. The results showed that the Young’s modulus of the composites increased with increasing clay content. The ratio of PMMA and EOC was 80/20 by weight and the clay content was 3 and 5 phr. The results showed Young’s modulus of the composites increased with increasing clay content. While the impact strength, tensile strength and percent strain at break of the composites decreased with increasing clay content. Scanning electron microscopy analysis showed that the droplet of dispersed EOC phase in PMMA matrix was changed to the elongated structure after adding clay.
Adhesion Characteristics of HA/MWCNT Composite
Authors: Lee Hong Cheol , Han Young Hwan , Lee Dong Yeon
Published: April 2015

Hydroxyapatite (HA) / Multi-walled Carbon Nanotube (MWCNT) composites were sintered by Spark Plasma Sintering (SPS). The adhesion characteristics of the composite are measured with Atomic Force Microscopy (AFM) at the different volume percent of MWCNT and the temperature. Experimental results have shown that the addition of MWCNT has caused the meaningful change in the adhesive force.
Application of Sorptive Building Materials Reducing Indoor Air Pollution for Improving Indoor Air Quality
Authors: Seo Jang Hoo , Park Seong Hyun , Lee Sun Woo
Published: April 2015

In order to improve indoor air quality, the interest in and the use of sorptive building materials that decrease the concentration of an indoor air pollutant have increased. The use of sorptive building materials is one way to decrease the concentration of an indoor pollutant that can adversely affect human health. In this study, we evaluated the effects of sorptive building materials applied to a wall on the decrease in the concentration of toluene emitted from the flooring. We also examined how the air exchange rate of the room, the loading factor of the sorptive materials, and the mass transfer coefficient influenced the sorptive performance; these effects were well reproduced experimentally with computational fluid dynamics (CFD) simulations. The results show that sorptive building materials have a fairly strong effect on the decrease in toluene concentrations in rooms and that this effect can be expected in real-world scenarios.
Iodinated Charcoal as Electrocatalyst for Oxygen Reduction Reaction
Authors: Jeon In Yup , Baek Jong Beom
Published: April 2015

Large quantity of iodinated charcoal (I-AC) is firstly prepared by simple ball-milling activated chargoalin the presence of iodine. The resultant I-AC contains iodine of 0.59 at.% (EDS) and shows that the morphology is changed from random powder into flake-like platelet. It is uased as electrocatalyst for oxygen reduction reaction (ORR), exhibiting outstanding electrocatalytic activities with higher selectivity, better tolerance to methanol crossover than those of the starting AC and commercial Pt/C electrocatalysts.
Research of Extensive Green Roof (Spring) for Create Comfortable Environment in Taiwan City
Authors: Chen Chiou Chuan
Published: April 2015

March to May at noon control area (exposed roof) temperature of 37.56°C, test below (green roofs) surface only 24.69°C, 24.79°C room temperature on the second floor, planting mean temperature of 27.6°C, effectively prevent the roof surface temperature rise, and thus reduce the interior roof of the second temperature 12.77°C . Building extensive green roofs to cooling, mainly to reduce the building room temperature of 3.76°C;reducing air conditioning electricity consumption , accomplish cooling and energy-saving benefits.March to May at noon (12:00-13:00), ANOVA analysis of cooling efficiency, the temperature difference between the building control area as the dependent variable, compare independent variables, and found that different monitoring areas of solar radiation cooling effect,2 floor indoor cooling temperature 13.9083°C, efficiency the most significant.Roofs of buildings spring will be applied as extensive green roof in spring, creating building roof thermal comfort (24.88°C) and Auliciems (1981) estimate room comfort temperature (24.55°C) are similar, significant benefits to achieve room thermal comfort.Buildings is applied for green roofs in the spring can reduce home power consumption (reducing air conditioning systems use frequency), to energy-saving (58.17%) of the economic benefits.
The Study of Stress Distribution on Meniscus Using 3D Finite Element Model
Authors: Laopachee Pavinee , Woraratsoontorn Pattaraweerin , Bamrungwongtaree Joompondej
Published: April 2015

Osteoarthritis is a degenerative disease of articular cartilageand meniscus that most experience in aged and obesity, always tend to grow up. Such bone surface degenerated will beirregular and has bone to grow called osteophyte. At moment making activities, the pain and the deformation of the knee joint are occurred thatcause decreasing quality of life. The deterioratedmeniscus has to encountersgradually changing the structureuntil it is not able to support the body weight. This paper proposes the preliminary studyof the knee jointbehavior, especially the meniscus during stand. Three dimensions (3-D) finite element (FE) model of the knee joint has constructed. This model consisted of femur, tibiaand meniscus without fibula.The external load were determined in each body weight and appliedon femur to evaluate maximum von-mises stress on the meniscus.The stress distribution on meniscus always occurs while exist the external load on the femur. The tendency of association between the external load and maximumstress was corresponding to that of the other author.
Silver-Coated Biologically Active Protein Hybrids: Antimicrobial Applications
Authors: Freeman Amihay , Dror Yael , Porat Carmit Ophir , Hadar Noa , Diamand Yossi Shacham
Published: April 2015

Novel hybrids, comprised of a biologically active protein molecule core, coated with a thin outer layer of porous metallic silver, were developed in our lab. By the conjugation of silver reducing polymer to the surface of soluble, molecular, biologically active protein molecules and subsequent addition of silver salt, electroless silver deposition, culminating in thin porous metallic coating, was directed to the surface of the protein molecules. The silver-protein hybrids thus obtained, presenting novel nanoparticles several nanometers in size, retained their solubility and biological activity.The silver coating combined with the retained biological activity of its protein core, paved the way to a series of biomedical applications of these hybrids including "wiring" of the active site of oxido-reductase enzyme to electrodes, imaging of the presence of targeted ligands displayed on cancer cell surface and antimicrobial enzymatically attenuated release of silver ions.In this presentation we shall overview the technology of protein-silver hybrid's fabrication and analytical applications of silver-glucose oxidase and silver-Avidin hybrids, followed by feasibility demonstration of using silver-glucose oxidase hybrid as novel antibacterial and antifungal agent.
Study of Yb-Doped CoSb3 Thermoelectric Thin Films Prepared by Laser
Authors: Jelínek Miroslav , Zeipl Radek , Kocourek Tomáš , Remsa Jan , Jurek Karel , Navrátil Jiří
Published: April 2015

Thin films of Yb filled CoSb3 were prepared on fused silica substrates using pulsed laser deposition method. The stoichiometric Yb0.19Co4Sb12 target was prepared by hot pressing method. The deposition conditions were changed with the goal to reach layers of smooth morphology. The target-to substrate distance was kept equal to 4 cm. The ambient argon pressure moved from 0.5 Pa to 13 Pa, laser repetition rate from 3 Hz to 10 Hz, and substrate temperature from 250 °C to 400 °C. We tested laser fluencies from 0.8 J·cm-2 to 5 J·cm-2. Films roughness was determined by mechanical profilometer and by atomic force microscopy. The lowest roughness of about 5 nm – 10 nm was reached for low laser fluencies but mechanical quality of films was poor and growth rate low (about 0.1 A/pulse). From WDX analysis follows that there is an excess of Yb and Sb compared to Yb0.19Co4Sb12 target.
Two-Step Sintering, Microstructure and Electrical Properties of (Ba, Ca)(Ti, Zr)O3 Lead-Free Ceramics
Authors: Bomlai Pornsuda
Published: April 2015

In this work, the (Ba1-xCax)(Ti1-yZry)O3 lead-free ceramics were prepared by the two-step sintering method, and effects of Ca and Zr contents on phase structure, densification, microstructure, and electrical properties were investigated. It was found that all samples showed orthorhombic phase. The highest density of 5.84 ± 0.01 g/cm3 was achieved in x = 0.05, y = 0.05 sample. The average grain size, phase transition temperature, dielectric and piezoelectric properties significantly decreased by introducing of the Ca/Zr content. The ceramics with a small amount of Ca and Zr maintain good piezoelectric properties, and a lower dielectric loss. The composition with x = 0.05, y = 0.025 demonstrated optimum electrical properties of d33 ∼211 pC/N, TC ∼ 119 °C, εr ∼ 1788, and tanδ ∼ 0.04.
Model Study of Partial Structural Decomposition of Thaumasite
Authors: Scholtzová Eva , Tunega Daniel
Published: April 2015

The DFT method was used for modeling a partial decomposition of the structure of the thaumasite mineral. The four models with a consecutive decreasing of water content were prepared (T12 – 100 %, T9 – 75 %, T6 – 50 %, T3 – 25 %) and corresponding decomposition enthalpies were calculated. The results showed a good agreement with available experimental data for the decomposition reaction of the thaumasite structure.
Evaluation on Adhesion Strength of Laser Induction Hybrid Rapid Cladding Cu-Fe-Based Coatings Using Scanning Kelvin Probe
Authors: Dai Xiao Qin , Zhou Sheng Feng , Xiong Zheng
Published: April 2015

It is very important to effectively evaluate the adhesion strength of coating. A nondestructive method to evaluate the adhesion strength of laser induction hybrid rapid cladding Cu-Fe-based coatings was investigated. The electron work function of coatings was measured by scanning Kelvin probe. It was demonstrated that the Fe-rich particles and solid solution of Fe can increase the EWF and the tensile strength. A logarithmic relationship between the ratio of EWF to dilution and the adhesion strength was established.
Nickel Release Rate of Type 303 Free Cutting Austenitic Stainless Steel
Authors: Yuan Jun Ping , Chen De Dong , Bo Hai Rui
Published: April 2015

Type 303 austenitic stainless steel has been applied in jewelry production, and its nickel release rate has become a concerned issue in the jewelry industry. In this paper, the commercial type 303 stainless steel was used as the test material, while 304 stainless steel as the contrast material; their nickel release rates and corrosion behaviors in artificial sweat were studied. The results show that the actually measured nickel release rate of 303 stainless steel reaches 2.06μg/cm2/week, nearly 25 times higher than that of 304 stainless steel, which exceeds the threshold specified in nickel release standard EN1811:2011 for jewelries coming into direct and prolonged contact with the skin (0.88μg/cm2/week), and its adjusted value also exceeds the threshold specified in Nickel Directive 2004/96/EC for puncture accessories (0.35μg/cm2/week). The high nickel release rate for 303 stainless steel is mainly caused by its high sulfur content and the inevitable formation of manganese sulfide inclusions, which will cause the pitting and exacerbate the material corrosion. Considering the risk of nickel sensitization of 303 stainless steel, it is not suggested to use 303 stainless steel as the jewelry material, especially for piercing jewelry.
Synthesis of ZSM-5 Zeolite without Organic Template
Authors: Yin Zhao Hua , Chen Yong , Wang Zhong Wei , Xing Ying , Tian Xiu Juan , Yu Qing , Meng Chang Gong
Published: April 2015

ZSM-5 zeolite was synthesized via a template-free method. The influence of crystallization time was investigated. The obtained samples were characterized by XRD, SEM and FTIR. Results shown that with the ratio of 8 Na2O : 80 SiO2 : 2 Al2O3 : 2500 H2O, the crystallization for ZSM-5 began at ca. 9 h. And fine ZSM-5 zeolite (ca. 10~15 μm) could be obtained by crystallizing at 190 °C for 10 h. Further increasing time would lead to the appearance of quartz.
Adsorption Simulation of Basic Nitrogen Compounds in ZSM-5 and USY Zeolites by Grand Canonical Monte Carlo Method
Authors: Liu Yi Bin , Li Yu Zhen , Ding Xue
Published: April 2015

Adsorption behaviors of pyridine, quinoline and isoquinoline in ZSM-5 and USY zeolites at 773 K were studied by Grand Canonical Monte Carlo simulations. Interaction energy, adsorption isothermal and localization for each adsorbate were obtained. The results show that pyridine and quinoline/isoquinoline molecules have different adsorption behaviors in the zeolite, while quinoline and isoquinoline molecules have similar adsorption behaviors. The maximum interaction energy between quinoline/isoquinoline and zeolite is more negative than that of pyridine and zeolite, which indicates that the quinoline/isoquinoline can be adsorbed more stable than pyridine. But the loadings of pyridine are significantly larger than that of quinoline/isoquinoline at the same pressure. Otherwise, pyridine can be adsorbed on most sites while quinoline/isoquinoline can only enter the large channels or cages. And the adsorption quantities in USY zeolite are much more than the adsorption quantities in ZSM-5 zeolite for each adsorbate.
Synthesis and Characterization of a New Fluorine-Containing Ultraviolet Light Absorber Based on BTA
Authors: Chen Zi Zi , Xiao Deng You , Shao Meng Yao , Sun Jia Jia , Xiang Bin
Published: April 2015

A novel fluorine-containing ultraviolet absorber (FBTA) based on the parent molecule 2-(2,4–dihydroxyphenyl)-2H-benzotriazol (BTA) was synthesized and characterized by 1HNMR, FTIR, and MS. UV absorption of FBTA was studied in 10-4 M dichloromethane (CH2Cl2), and the results suggested that FBTA possessed similar UV absorption capability with BTA.
The Utilization of Phenol Components in Bio-Oil for Modifying Urea-Formaldehyde Resin Adhesive
Authors: Cheng Yi , Tian Qi Kui , Li Rui
Published: April 2015

The components in bio-oil are mainly concluding organic acid, aldehydes and phenolics. As the irregular cracking of the pyrolysis, the products are complex and difficult to separate. A comprehensive concept was presented and the extractions from bio-oil were used for modifying urea-formaldehyde (UF) resin in this study. Characterization by FT-IR and GC-MS indicated that the reaction mechanism. Phenol-oil addition amount and particle boards test were investigated resulted those 10% phenol-oil shows the best properties: viscosity of 73.36 mm/s, solid content of 52.25% and pH of 8.35 and the best pressing condition is 125°C for 5min which produce a 1.23MPa bond strengthen and 1.05 mg/L formaldehyde emission plywood.
The Research on Adsorption of MB by SPES Microspheres and SPES Microspheres Wrapping Titanium Dioxide
Authors: Wu Kun Hong , Huang Fang
Published: April 2015

The polyethersulfone(PES) and sulfonated polyethersulfone(SPES) microspheres which all wraps titanium dioxide could be prepared by solvent evaporation method of double emulsion systems(W1/O/W2) or coagulation bath method. The results on the adsorption performance of methylene blue(MB) by PES and SPES microspheres wrapping titanium dioxide, SPES microspheres excluding titanium dioxide and the comparison of the isothermal and dynamic adsorption of SPES showed that, the adsorption performance of MB by SPES wrapping titanium dioxide is better than PES wrapping titanium dioxide, and the SPES excluding titanium dioxide is better than which wraps titanium dioxide.
Study of Errors on Larch Wood Pyrolysis Kinetic Analysis
Authors: Xu Lan Shu , Cheng Yi , Li Yu Yu , Li Rui
Published: April 2015

Errors was generate when use integral methods to calculate pyrolysis kinetic. It was analyzed by considered the effects of methods and reaction orders. A α-T curve was established for the error discussion depending on basic kenotic theory. For analysis methods, both single curve and multiple curve methods can obtain reliable activation energy values (≤3%), but the error of frequency factor was significant (up to 40%). Frequency factor is sensitive to intercept changing and is also to reaction order. Magnitude error could show if reaction order deviates to true value.
Numerical Analysis of Semi-Solid Die-Casting Automobile Part Based on the Thermo-Visco-Plastic Constitutive Relation
Authors: Wang Jiao Jiao , Lu Gui Min , Yu Jian Guo
Published: April 2015

Thermal simulation compression tests were performed on semi-solid billet in order to observe and investigate the behavior of 6061 aluminum alloys while varying the processing parameters such as apparent viscosity, the shear rate and the temperature. Specimens of 6061 aluminum alloys were characterized with their semi-solid behavior during partial melting and holding in the semi-solid state. Furthermore, the constitutive equation of semi-solid 6061 aluminum alloys was investigated. Moreover, the tests allow the apparent viscosity and shear rate of the alloys to be determined as a function of the solid volume fraction and strain rate together with the geometry behavior of the specimen. Utilizing these parameters, semi-solid die casting process of 6061 aluminum alloys could be simulated by the change of the solid volume fractions.
A Modified Monte-Carlo Potts Model for Dynamic Recrystallization
Authors: Fu Jian , Peng Bi You , Xie Bin , Ye Yi Gen
Published: April 2015

In order to improve the microstructure evolution modeling of dynamic recrystallization (DRX) in agreement with physical experiment, a modified Monte-Carlo (MC) Potts model for simulating DRX process was proposed in this paper under the consideration of the inhomogeneous stored energy distribution related to grain sizes, the nucleation criteria related to critical dislocation density, the site energy change related to grain preferred-growth, the combination of macroscopic thermo-mechanical parameters and microscopic material parameters, and the relationship between MC calculation steps and real DRX time. The results show that the modified model can better simulate the basic characteristics of dynamic recrystallization of metallic materials during forging, which the recrystallized grains nucleate mainly in the deformed regions with high stored energy and preferentially grow up by merging adjacent deformed grains with high stored energy.
Application of Ant Colony Algorithm in Optimal Preform Design of Forging Process
Authors: Zhao Xin Hai , Bai Jian Chang , Zhao Guo Qun
Published: April 2015

For the forging with complex shape, the preform design is a difficult problem in the process and die design. It has an enormous influence on the quality of the forging. In this paper, combining with the FEM, the Ant Colony Algorithm was used for the preform optimization design. The general Ant Colony Algorithm was improved to fit for the multivariate continuous function optimization. The preform die shape was represented by B-spline and the coordinates of the control point of the B-spline were taken as the optimization design variables. The optimization program was developed. Finally, aimed to decrease the material cost of the forging, the preform optimization of a typical H-section forging was obtained using the self-developed program. The optimization results show that the improved Ant Colony Algorithm is suitable for the preform optimization design of forging.
A Novel Modified Paris’ Law Based Evaluation of Fatigue Crack Propagation of LD2 under Combination of Corrosion and Cyclic Loadings
Authors: Li Xu Dong , Lv Hang , Wang Wen Xiu
Published: April 2015

The present thesis made a research to evaluate fatigue crack growth rate subjecting to corrosion and cyclic fatigue loading, with the effect of load frequency on fatigue taken into account. A modified Paris’ law based model is proposed. An exponential modified expression of proportional parameter account for fatigue frequency is proposed based on the obvious fact that low frequency loading will lead to long fatigue life, thus prolong interaction time between corrosion media and specimen which will favor for crack propagation. Loading frequency higher enough will shorten that time, thus influence of corrosion will be significantly weaken, close to pure mechanical fatigue. Crack growth rate prediction from proposed formula is proved to be in good agreement with experimental results for steadily extended corrosion fatigue crack.
π-Lithium Noncovalent Interaction between π-Bond-Containing Compounds and NH2Li: A way of Construction for Supramolecular Materials
Authors: Yuan Kun , Lv Ling Ling
Published: April 2015

In this paper, we optimized the geometries the π-lithium bond complexes between three π-bond-containing compounds, ethylene, acetylene, benzene, and amido-lithium have been calculated at DFT-D3/6-311++G**, MP2/6-311++G** and QCISD/6-311++G** theoretical levels. All the equilibrium geometries were confirmed to be stable state by analytical frequency computations. The calculations showed that all the bond lengths of the electron acceptors increased obviously and the red shift of N-Li stretching frequency occurred after complexes formed. The calculated binding energies, ΔEtot, of the four complexes are-38.11, -41.05 and-45.02 kJ·mol-1via the DFT-D3 method, respectively. Natural bond orbital theory analysis revealed that the three complexes were all formed with π-s type lithium bond interaction between three π-lithium bond donor molecules.
A Method for Preparing Sample Used in Evaluating Adhesion Performance of Hot Melt Adhesives in Textiles
Authors: Huang Gui Fang , Li Zhe Long , Zhu Wan Yu , Zeng Zuo Xiang
Published: April 2015

A method for preparing sample is proposed to evaluate adhesion performance of hot melt adhesives (HMAs) applied in textiles by drawing wire. Two HMAs of copolyester were prepared. The peel bond strength (S) data of Fabric 6535 samples laminated by copolyester showed thatSincreased with increasing diameter when filament diameter is less than reasonable diameter (Dr), and then came to a stable value. The reliability of drawing wire method was verified by pastedot coating method, and the results showed that the method proposed here is applicable and convenient.
The Application of Moldflow in Injection Molding of the Helmet
Authors: Huang Yong Cheng , Liu Hong Bin , Wu Hai Tao
Published: April 2015

Considering the importance of the reasonable injection molding technology.Based on the application of moldflow in injection molding of the helmet .By adjusting the mold temperature, melt temperature, injection time, packing pressure, hold time and so on the injection molding process parameters to develop appropriate technology methods to get the best injection molding parameters.
The Treatment of Waste Metal Cutting Fluid by Extraction and Adsorption Process
Authors: Shan Hou Zhuang , Li Tian Yi , Li Yan Zhen , Chen Shao Hui
Published: April 2015

A novel recovery process of the effective ingredient from the waste metal cutting fluid was proposed by the combination of solvent extraction and solid adsorption technique. The influence factors such as the volume fraction of 1-butanol, the ratio of solvent to oil, the quantities of KOH and the extraction temperature were studied through experiments. The results show that: The maximum quality of oil sludge was obtained when added 3g KOH to waste liquid(200ml).The mass of oil sludge was found to increase with the increase of solvent to oil ratio until it reached the maximum at the ratio of 3:1.
The Effect of KMnO4 Concentration on the Catalytic Activity of MnOx/Luffa Sponge Composites
Authors: Han Xiao , Feng Li Li , Li Jin Ge , Zhang Peng Yi , Li Hao
Published: April 2015

MnOx/ luffa sponge composites were prepared by loading MnOx on/in porous luffa sponge under ambient conditions and an in-situ reduction method. We employed the oxidative decomposition of HCHO as probe reaction to investigate the effect of KMnO4 concentration on the catalytic activity of MnOx/ luffa sponge composites. It is shown that all the MnOx/ luffa sponge composites bear the activity for the catalytic decomposition of HCHO; the conversion of HCHO was found to be high at room temperature; the conversion level of HCHO was first increased and then decreased with the increase in the KMnO4 concentration. The HCHO conversion over the catalyst prepared from 10 g/L of KMnO4 solution was the largest among five catalysts.
Flame Retardation of Banana Fiber Reinforced Epoxy Composites Using Melamine Pyrophosphate and Pentaerythritol as Intumescent Flame Retardants
Authors: Pang Jin Ying , Mo Xian Zhong , Liu Yu Xin , Zhu Yong Fei
Published: April 2015

Flame retardation of banana fiber reinforced epoxy composites using melamine pyrophosphate and pentaerythritol as intumescent flame retardants and the influence of mechanical properties were investigated. The effects of IFR contents and the ratio of MPP and PER on limiting oxygen index (LOI) and UL94 rating of banana fiber reinforced epoxy composites has been studied. It was found that the combustion performance of the composites increases with increasing IFR contents,and the composites at the ratio of MPP/PER=2:1(weight ratio) at the same loading 40% showed the best combustion performance with IFR contents increasing,the limiting oxygen index (LOI) increased and UL94 rating reached, but the mechanical properties of composites significantly decreased. In order to increase the comprehensive properties, the flame retarded fiber was used to prepared the composites,the limiting oxygen index (LOI) of the composites significantly increased. the best complex properties were the IFR contents was 40%, the ratio of MPP/PER=2:1 (weight ratio), by the spraying method with 20g the fire retardant liquid of every 30g banana fiber.
Fabrication and Characterization of Aramid/Aerogel Composite
Authors: Yao Li Rong , Ren Juan , Xu Shan Qing
Published: April 2015

The LiCl/DMAc was used as solvent system to dissolve meta-aramid short fiber, the aramid fibrid was prepared by injecting the aramid solution into the high shearing coagulant at room temperature and the mixture of water and N, N-dimethylacetamide (DMAc) was used as coagulant. The aramid fibrid and aramid short fiber were mixed at differents weight proportion, wet paper was dried and aramid paper was prepared by heat pressing. The aramid paper has excellent mechanical properties when the weight proportion of the aramid fibrid and aramid short fiber was 60:40,and it had a good thermal bonding between the fibrid and fiber under heat pressing. The hydrophobic SiO2 was mixed with aramid fibrid and aramid short fiber (60:40) in ethanol, and aramid/aerogel composite was prepared by drying and hot compressing. The composite had a good heat-resisting, however, the mechanical property decreased with the content of aerogel increasing.
Performance and Morphology of PVDF/PEG-POSS Hybrid Membrane
Authors: Hu Fang , Sun Jun Fen
Published: April 2015

Polyvinylidene fluoride (PVDF)/PEG-POSS hybrid membrane was prepared by immersion phase separation process. The hybrid membranes were characterized by pure water flux, retention ratio to BSA, contact angle, shrinkage ratio and scanning electron microscopy (SEM). The hydrophilicity of the membrane was improved. The contact angles decreases from 82.2°to 76.3°. The shrinkage ratio decreases and the pure water flux increased when 1.0% POSS was used.Keywords: polyvinylidene fluoride (PVDF); PEG-POSS; hybrid membrane; hydrophilicity