Advances in Materials Science and Engineering The latest articles from Hindawi Publishing Corporation © 2015 , Hindawi Publishing Corporation . All rights reserved. Experimental Research for the Application of Mining Waste in the Trench Cutting Remixing Deep Wall Method Sun, 01 Feb 2015 12:53:19 +0000 This paper focuses on the use of fly ash (FA) or ground granulated blast slag (GGBS) and reactive lime blends for cement-stabilized Nanjing clay, comparing them with Portland cement (PC) for enhanced technical performance. A range of tests were conducted to investigate the properties of stabilized soils, including macrostrength (UCS), permeability, and microstructure analyses by scanning electron microscopy (SEM). The influence of PC : (FA + lime) ratio, PC : (GGBS + lime) ratio and curing time was addressed. The UCS and permeability results revealed that PC-FA-lime was more efficient than PC-GGBS-lime as a binder for soil stabilization, with an optimum proportion of PC : (FA + lime) = 3 : 7 at 25% binder content, varying with curing time. The microstructure analysis reveals that fly ash mainly changes the pore volume distribution, which ranges between 0.01 μm and 1 μm, and produces more CSH/CASH bonding and fissures due to the secondary hydration and pozzolanic reactions. Based on the favourable results obtained, it can be concluded that the soft soils can be successfully stabilized by the combined action of cement, fly ash, and lime. Since fly ash is much cheaper than cement, the addition of fly ash and lime in cement-soil mix may particularly become attractive and can result in cost reduction of construction. Yan Chao, Liu Songyu, and Deng Yongfeng Copyright © 2015 Yan Chao et al. All rights reserved. TiC0.5N0.5-Based Cermets with Varied Amounts of Si3N4 Nanopowders Prepared by Spark Plasma Sintering Sun, 01 Feb 2015 12:14:05 +0000 TiCN-based cermets with varied fractions of Si3N4 nanopowder (0–5 wt.%) were prepared by spark plasma sintering. The microstructural and mechanical properties of these cermets were investigated. In general, with increasing addition amount of Si3N4 nanopowder the relative density as well as mechanical properties of the as-prepared TiCN cermets increased first and then decreased. The samples containing 2 wt.% Si3N4 nanopowder presented the best performance with the relative density of about 98%, bending strength of 1000 MPa, and Vickers microhardness of about 1810 HV10. Changchun Lv, Zhijian Peng, Zhiqiang Fu, and Chengbiao Wang Copyright © 2015 Changchun Lv et al. All rights reserved. Effect of Pore Size on the Biodegradation Rate of Silk Fibroin Scaffolds Sun, 01 Feb 2015 09:35:45 +0000 Controlling the degradation rate of silk fibroin-based biomaterial is an important capability for the fabrication of silk-based tissue engineering scaffolds. In this study, scaffolds with different pore sizes were prepared by controlling the freezing temperature and the silk fibroin concentration. In vitro degradation results showed that the internal pore walls of the scaffolds with a larger pore size collapsed upon exposure to collagenase IA for times ranging from 6 to 12 days, and the silk scaffolds exhibited a faster rate of weight loss. The morphological and structural features of the silk scaffolds with a smaller pore size maintained structural integrity after incubation in the protease solution for 18 days, and the rate of weight loss was relatively slow. Scaffolds with a smaller pore size or a higher pore density degraded more slowly than scaffolds with a larger pore size or lower pore density. These results demonstrate that the pore size of silk biomaterials is crucial in controlling the degradation rate of tissue engineering scaffolds. Zuwei Luo, Qin Zhang, Meijing Shi, Yang Zhang, Wei Tao, and Mingzhong Li Copyright © 2015 Zuwei Luo et al. All rights reserved. Temperature and pH Responsive Microfibers for Controllable and Variable Ibuprofen Delivery Thu, 29 Jan 2015 09:01:31 +0000 Electrospun microfibers (MFs) composed of pH and temperature responsive polymers can be used for controllable and variable delivery of ibuprofen. First, electrospinning technique was employed to prepare poly(ε-caprolactone) (PCL) and poly(N-isopropylacrylamide-co-methacrylic acid) (pNIPAM-co-MAA) MFs containing ibuprofen. It was found that drug release rates from PCL MFs cannot be significantly varied by either temperature (22–40°C) or pH values (1.7–7.4). In contrast, the ibuprofen (IP) diffusion rates from pNIPAM-co-MAA MFs were very sensitive to changes in both temperature and pH. The IP release from pNIPAM-co-MAA MFs was highly linear and controllable when the temperature was above the lower critical solution temperature (LCST) of pNIPAM-co-MAA (33°C) and the pH was lower than the of carboxylic acids (pH 2). At room temperature, however, the release rate was dramatically increased by nearly ten times compared to that at higher temperature and lower pH. Such a unique and controllable drug delivery system could be naturally envisioned to find many practical applications in biomedical and pharmaceutical sciences such as programmable transdermal drug delivery. Toan Tran, Mariana Hernandez, Dhruvil Patel, and Ji Wu Copyright © 2015 Toan Tran et al. All rights reserved. Synthesis of Micro- and Nanoparticles of Metal Oxides and Their Application for Reinforcement of Al-Based Alloys Wed, 28 Jan 2015 09:54:47 +0000 This paper presents a comparative analysis of morphology, chemical and phase compositions, and particle size distribution of nanopowders produced by electric explosion of wire (EEW) and plasma-chemical methods. The possibility of introduction of Al2O3 particles into Al alloy by means of a special master alloy and with ultrasonic processing is shown. The improvement of tensile properties of an Al-based composite material reinforced with 0.1 wt% of EEW Al2O3 is demonstrated. S. Vorozhtsov, I. Zhukov, A. Vorozhtsov, A. Zhukov, D. Eskin, and A. Kvetinskaya Copyright © 2015 S. Vorozhtsov et al. All rights reserved. Effect of Nanosized NiF2 Addition on the Transport Critical Current Density of Ag-Sheathed (Bi1.6Pb0.4)Sr2Ca2Cu3O10 Superconductor Tapes Wed, 28 Jan 2015 09:40:20 +0000 We report the effect of NiF2 (10 nm) additions on the transport critical current density, of (Bi1.6Pb0.4)Sr2Ca2Cu3O10/Ag sheathed superconductor tapes. Pellets of (Bi1.6Pb0.4)Sr2Ca2Cu3O10(NiF2)x (–0.05 wt.%) superconductor were prepared using the acetate coprecipitation method. The sample with 0.04 wt.% addition of NiF2 exhibited the highest . Ag-sheathed (Bi1.6Pb0.4)Sr2Ca2Cu3O10(NiF2)0.04 superconductor tapes were fabricated using the powder-in-tube (PIT) method and sintered at 845°C for 50 and 100 h. of nonadded tapes at 30 K sintered for 50 and 100 h was 6370 and 8280 A/cm2, respectively. of (Bi1.6Pb0.4)Sr2Ca2Cu3O10(NiF2)0.04/Ag tape at 30 K sintered for 50 and 100 h was 14390 and 17270 A/cm2, respectively. In magnetic fields (0 to 0.7 T), of the NiF2 added tapes was also higher compared with the nonadded tape indicating that NiF2 nanoparticles can act as effective flux pinning centers and longer sintering time improved the microstructure. A steeper increase in was observed below 60 K in the NiF2 added tapes which coincided with the Neel temperature, of nanosized NiF2 (60 K). The pronounced enhancement of was attributed to the strong interaction between flux line network and the antiferromagnetic NiF2 below . M. Hafiz and R. Abd-Shukor Copyright © 2015 M. Hafiz and R. Abd-Shukor. All rights reserved. Computational Approach in Formulating Mechanical Characteristics of 3D Star Honeycomb Auxetic Structure Tue, 27 Jan 2015 08:54:46 +0000 Auxetic materials exhibit a unique characteristic due to the altered microstructure. Different structures have been used to model these materials. This paper treats a development of finite element model and theoretical formulation of 3D star honeycomb structure of these materials. Various shape parameters of the structural cell were evaluated with respect to the basic mechanical properties of the cell. Finite element and analytical approach for various geometrical parameters were numerically used to formulate the characteristics of the material. The study aims at quantifying mechanical properties for any domain in which auxetic material is of interest for variations in geometrical parameters. It is evident that mechanical properties of the material could be controlled by changing the base wall angle of the configuration. The primary outcome of the study is a design guideline for the use of 3D star honeycomb auxetic cellular structure in structural applications. Mozafar Shokri Rad, Zaini Ahmad, and Amran Alias Copyright © 2015 Mozafar Shokri Rad et al. All rights reserved. Ostwald Ripening Process of Coherent β′ Precipitates during Aging in Fe0.75Ni0.10Al0.15 and Fe0.74Ni0.10Al0.15Cr0.01 Alloys Tue, 27 Jan 2015 06:56:26 +0000 The Ostwald ripening process was studied in Fe0.75Ni0.10Al0.15 and Fe0.74Ni0.10Al0.15Cr0.01 alloys after aging at 750, 850, and 950°C for different times. The microstructural evolution shows a rounded cube morphology (Fe, Ni)Al β′ precipitates aligned in the ferrite matrix, which changes to elongated plates after prolonged aging. The variation of the equivalent radii of precipitates with time follows the modified Lifshitz-Slyozov-Wagner theory for diffusion-controlled coarsening. Thermo-Calc analysis shows that the chromium content is richer in the matrix than in the precipitates which causes higher hardness and coarsening resistance in the aged Fe0.74Ni0.10Al0.15Cr0.01 alloy. N. Cayetano-Castro, M. L. Saucedo-Muñoz, H. J. Dorantes-Rosales, Jorge L. Gonzalez-Velazquez, J. D. Villegas-Cardenas, and V. M. Lopez-Hirata Copyright © 2015 N. Cayetano-Castro et al. All rights reserved. Magnetic Properties and Core Loss Behavior of Fe-6.5wt.%Si Ribbons Prepared by Melt Spinning Mon, 26 Jan 2015 14:31:48 +0000 Fe-6.5wt.%Si alloy is prepared in the form of continuous ribbons with 25 mm in width and 0.03 mm in thickness by using melt spinning technique. The ribbons are flexible and could be wounded into tapes. DC magnetic properties and core loss behaviors of the ribbons after heat treatment are investigated in this paper. The magnetic properties are compared with ribbons by cold rolling and CVD methods. The melt spinning ribbons exhibit much less core loss in the frequencies more than 10 kHz. The melt spinning ribbons are promising to be used for electric devices used in medium or higher frequencies. S. Wang, Y. M. Jiang, Y. F. Liang, F. Ye, and J. P. Lin Copyright © 2015 S. Wang et al. All rights reserved. Correlation of Grain Size, Stacking Fault Energy, and Texture in Cu-Al Alloys Deformed under Simulated Rolling Conditions Mon, 26 Jan 2015 13:07:27 +0000 The effect of grain size and stacking fault energy (SFE) on the strain hardening rate behavior under plane strain compression (PSC) is investigated for pure Cu and binary Cu-Al alloys containing 1, 2, 4.7, and 7 wt. % Al. The alloys studied have a wide range of SFE from a low SFE of 4.5 mJm−2 for Cu-7Al to a medium SFE of 78 mJm−2 for pure Cu. A series of PSC tests have been conducted on these alloys for three average grain sizes of ~15, 70, and 250 m. Strain hardening rate curves were obtained and a criterion relating twinning stress to grain size is established. It is concluded that the stress required for twinning initiation decreases with increasing grain size. Low values of SFE have an indirect influence on twinning stress by increasing the strain hardening rate which is reflected in building up the critical dislocation density needed to initiate mechanical twinning. A study on the effect of grain size on the intensity of the brass texture component for the low SFE alloys has revealed the reduction of the orientation density of that component with increasing grain size. Ehab A. El-Danaf, Mahmoud S. Soliman, and Ayman A. Al-Mutlaq Copyright © 2015 Ehab A. El-Danaf et al. All rights reserved. Analysis of Disturbing Influence of Traffic Load on Soil Body Mon, 26 Jan 2015 07:29:46 +0000 Stress waves propagate in soil in case of earthquake and man-made effects (traffic flow, buried explosions, shield-driven pipes and tunnels, etc.). The wave point-sources are those located at the distances equal to more than two waves lengths, which significantly simplifies solving of a problem of these waves’ strength evaluation. Distribution of stress and displacement by the stress waves propagation in elastic medium is a complex pattern. The stress distribution in propagating waves depends on the type and form of source, conditions of the source contact with medium, and properties of mediums in the vicinity of the source. The point-sources and their combinations are selected in such a way to model an influence of machines and processes on soil body in case of shield-driven pipes (tunnels). Janat Musayev and Algazy Zhauyt Copyright © 2015 Janat Musayev and Algazy Zhauyt. All rights reserved. The Phase-Formation Behavior of Composite Ceramic Powders Synthesized by Utilizing Rice Husk Ash from the Biomass Cogeneration Plant Mon, 26 Jan 2015 06:26:57 +0000 The development and utilization of biomass as a vital source of renewable energy were stimulated in order to reduce the global dependency on fossil fuels. A lot of rice husk ashes (RHA) were generated as the waste after the rice husk as the main fuel was burnt in the biomass cogeneration plant. The phase-formation behavior of composite ceramic powders synthesized by using rice husk ash from the biomass cogeneration plant at the different carbon ratios and temperatures was investigated. The sequence of phase formation with the calcining temperatures ranging from 1773 K to 1853 K was followed by O′-SialonSiC + Si3N4SiC in samples with C/SiO2  =  1 : 1–4 : 1. Ca--Sialon formed in samples with C/SiO2  =  5 : 1 and 6 : 1. The results highlighted that series of reactions happening sensitively depended on C/SiO2 and the temperature and demonstrated that the carbothermal nitridation provided an alternative for converting RHA waste into composite ceramic powders. Wenjie Yuan, Mingyu Fan, Chengji Deng, Jun Li, and Hongxi Zhu Copyright © 2015 Wenjie Yuan et al. All rights reserved. Experimental Study on Dry Friction Damping Characteristics of the Steam Turbine Blade Material with Nonconforming Contacts Thu, 22 Jan 2015 13:27:03 +0000 An experiment system has been established to study the dry friction damping dynamic characteristics of the steam turbine blade material 1Cr13. The friction dynamic characteristics of the specimens with nonconforming contact surfaces are measured under different parameters. The experiment results are compared with that of the macroslip hysteresis model and the Mindlin microslip friction model in detail. The results show that the experimental result of the tangential contact stiffness is in good agreement with that of the theory result based on the fractal theory and the Hertz contact theory by Jiang et al., 2009. The dimensionless equivalent stiffness and equivalent damping obtained by the macroslip hysteresis model agree well with the experimental results when relative motion is relatively large. However, the results of the macroslip hysteresis model differ a lot from the experimental results when relative motion is relatively small. Compared with the macroslip hysteresis model, the Mindlin microslip friction model can predict the dimensionless equivalent stiffness and equivalent damping accurately during the whole measurement range. The linear regularities of dimensionless equivalent stiffness and equivalent damping are obtained, which decrease the difficulty of building the vibration analysis model of the blade with sufficient accuracy. Jun Wu, Ruishan Yuan, Zhenwu He, Di Zhang, and Yonghui Xie Copyright © 2015 Jun Wu et al. All rights reserved. A Precipitation Phenomenon of Titanium Compounds in Aluminum Melts and the Refinement Fading Mechanism of the Al-5Ti-0.62C Master Alloy Thu, 22 Jan 2015 06:28:05 +0000 The Al-5Ti-0.62C master alloy was prepared through a method of thermal explosion in molten aluminum. The process of remelting and refining of commercially pure aluminum was conducted, and precipitation samples with different heat-treatment times were obtained. Scanning electron microscopy (SEM), X-ray diffraction (XRD), optical microscopy (OM), and other techniques were used to analyze the microstructure of the precipitates at the bottom of the samples so as to explore the fading mechanism of Al-Ti-C alloy refinement. The results showed that an obvious precipitation phenomenon of titanium compounds existed in the remelted Al-5Ti-0.62C master alloy and that there were both TiC compounds and TiAl3 compounds in the precipitates; in the refined pure aluminum samples, the precipitates were mainly TiC compounds. Precipitation of titanium compounds in aluminum melting is the main cause of fading in the refinement effect of an Al-Ti-C master alloy. Wanwu Ding, Wenjun Zhao, and Tiandong Xia Copyright © 2015 Wanwu Ding et al. All rights reserved. Microstructures and Toughening of TiC-TiB2 Ceramic Composites with Cr-Based Alloy Phase Prepared by Combustion Synthesis in High-Gravity Field Tue, 20 Jan 2015 10:38:49 +0000 Micro-nanocrystalline microstructures which are characterized by TiB2 platelets of the average thickness close to or smaller than 1 μm can be achieved in nearly full-density solidified TiC-TiB2 ceramic composites with Cr-based alloy phases by combustion synthesis in ultra-high gravity field of 2500 g. The filler phases in ceramic composites are actually Cr-based alloy with a little solidified solution of Ni atoms and Al atoms. The hardness, flexural strength, and fracture toughness of the materials are 18.5 ± 1.5 GPa, 650 ± 35 MPa, and 16.5 ± 1.5 MPa⋅m0.5, respectively. The improved fracture toughness of TiC-TiB2 ceramic composites results from crack deflection, crack bridging, and pull-out by a large number of fine TiB2 platelets and plastic deformation with some Cr-based alloy phases. Xuegang Huang, Chun Yin, Zhongmin Zhao, Long Zhang, and Junyan Wu Copyright © 2015 Xuegang Huang et al. All rights reserved. Optimized Design of an ECAP Die Using the Finite Element Method for Obtaining Nanostructured Materials Tue, 20 Jan 2015 07:02:39 +0000 An alloy type A16060 was exposed to severe plastic deformation to study its reaction using the finite element method (FEM). To perform this, six different configurations were used in the design of the die’s channel for ECAP (equal channel angular pressing) to obtain nanostructure materials and to optimize the process. Thanks to simulation performed with FEM, it is possible to study the homogeneity in the deformation due to the variation of conditions affecting directly the material being processed using the ECAP technique, such as the friction coefficient, extrusion speed, and mainly the die’s channel geometry being utilized in the ECAP process. Due to the tensile strain area being located mainly in the upper part of the deformed test cylinder (plastic deformation area) which increases the fracture and cracking tendency preventing the processing through ECAP the die being utilized was modified to eliminate the tensile strain area favoring the appearance of compressive stress which reduces the cracking tendency and the fracture of the sample being processed. The FEM analysis demonstrated that the strain state changed significantly from tension to compression when the modified die was used, facilitating the processing of the piece by ECAP. Patricia Ponce-Peña, Edgar López-Chipres, Edgar García-Sánchez, Miguel Angel Escobedo-Bretado, Brenda Xiomara Ochoa-Salazar, and María Azucena González-Lozano Copyright © 2015 Patricia Ponce-Peña et al. All rights reserved. Water Permeability of Pervious Concrete Is Dependent on the Applied Pressure and Testing Methods Sun, 18 Jan 2015 09:34:15 +0000 Falling head method (FHM) and constant head method (CHM) are, respectively, used to test the water permeability of permeable concrete, using different water heads on the testing samples. The results indicate the apparent permeability of pervious concrete decreasing with the applied water head. The results also demonstrate the permeability measured from the FHM is lower than that from the CHM. The fundamental difference between the CHM and FHM is examined from the theory of fluid flowing through porous media. The testing results suggest that the water permeability of permeable concrete should be reported with the applied pressure and the associated testing method. Yinghong Qin, Haifeng Yang, Zhiheng Deng, and Jiang He Copyright © 2015 Yinghong Qin et al. All rights reserved. Aluminium Process Fault Detection and Diagnosis Thu, 15 Jan 2015 11:27:42 +0000 The challenges in developing a fault detection and diagnosis system for industrial applications are not inconsiderable, particularly complex materials processing operations such as aluminium smelting. However, the organizing into groups of the various fault detection and diagnostic systems of the aluminium smelting process can assist in the identification of the key elements of an effective monitoring system. This paper reviews aluminium process fault detection and diagnosis systems and proposes a taxonomy that includes four key elements: knowledge, techniques, usage frequency, and results presentation. Each element is explained together with examples of existing systems. A fault detection and diagnosis system developed based on the proposed taxonomy is demonstrated using aluminium smelting data. A potential new strategy for improving fault diagnosis is discussed based on the ability of the new technology, augmented reality, to augment operators’ view of an industrial plant, so that it permits a situation-oriented action in real working environments. Nazatul Aini Abd Majid, Mark P. Taylor, John J. J. Chen, and Brent R. Young Copyright © 2015 Nazatul Aini Abd Majid et al. All rights reserved. Adsorption of Atenolol on Kaolinite Sun, 11 Jan 2015 12:37:58 +0000 In this study the adsorption of atenolol (AT), a -blocker, on kaolinite, a clay mineral of low surface charge, was investigated under varying initial AT concentration, equilibrium time, solution pH, ionic strength, and temperature conditions. The results showed that the amounts of AT uptake by kaolinite were close to its cation exchange capacity value and the AT adsorption was almost instantaneous, suggesting a surface adsorption. The adsorption was exothermic and the free energy of adsorption was small negative, indicating physical adsorption. The increase in ionic strength of the solution drastically reduced AT uptake on kaolinite. A significant reduction in AT uptake was found at solution pH below 5 or above 10. The FTIR results showed band shifting and disappearance for NH bending vibration and benzene ring skeletal vibration at 3360 and 1515 cm−1 and band splitting at 1412 and 1240 cm−1 attributed to C–N valence vibration coupled with NH bending vibrations and alkyl aryl ether linkage, suggesting the participation of NH, –O–, and benzene ring for AT adsorption on kaolinite. Yingmo Hu, Nicole M. Fitzgerald, Guocheng Lv, Xuebing Xing, Wei-Teh Jiang, and Zhaohui Li Copyright © 2015 Yingmo Hu et al. All rights reserved. Studying the Effect of ZnO on Physical and Elastic Properties of (ZnO)x(P2O5)1−x Glasses Using Nondestructive Ultrasonic Method Tue, 06 Jan 2015 14:41:24 +0000 Binary zinc phosphate glass system with composition of (ZnO)x(P2O5)1−x, ( = 0.1, 0.2, 0.3, 0.4, 0.5 and 0.6 mol%) was successfully prepared using a conventional melt-quenching method. Composition dependence of physical properties and elastic properties in the (ZnO)x(P2O5)1−x were discussed in association with the effects of adding zinc oxide (ZnO) as a modifier. The addition of ZnO modifier was expected to produce substantial changes on physical properties of the phosphate glasses. An increase in density values of the phosphate glasses was observed. Elastic moduli were studied by measuring ultrasonic longitudinal and shear velocities ( and ) of the glasses at room. Longitudinal modulus, shear modulus, bulk modulus, Young’s modulus, Poisson’s ratio, and Debye temperature were derived from both data of velocities and respective density of all of the samples. Findings from present work showed dependence of density and elastic moduli of each ZnO-P2O5 series on glass composition. Khamirul Amin Matori, Mohd Hafiz Mohd Zaid, Hock Jin Quah, Sidek Hj. Abdul Aziz, Zaidan Abdul Wahab, and Mohd Sabri Mohd Ghazali Copyright © 2015 Khamirul Amin Matori et al. All rights reserved. Microstructure and Wear Behavior of CoCrFeMnNbNi High-Entropy Alloy Coating by TIG Cladding Tue, 06 Jan 2015 07:08:30 +0000 Alloy cladding coatings are widely prepared on the surface of tools and machines. High-entropy alloys are potential replacements of nickel-, iron-, and cobalt-base alloys in machining due to their excellent strength and toughness. In this work, CoCrFeMnNbNi HEA coating was produced on AISI 304 steel by tungsten inert gas cladding. The microstructure and wear behavior of the cladding coating were studied by X-ray diffraction, scanning electron microscopy, energy dispersive spectrometer, microhardness tester, pin-on-ring wear tester, and 3D confocal laser scanning microscope. The microstructure showed up as a nanoscale lamellar structure matrix which is a face-centered-cubic solid solution and niobium-rich Laves phase. The microhardness of the cladding coating is greater than the structure. The cladding coating has excellent wear resistance under the condition of dry sliding wear, and the microploughing in the worn cladding coating is shallower and finer than the worn structure, which is related to composition changes caused by forming the nanoscale lamellar structure of Laves phase. Wen-yi Huo, Hai-fang Shi, Xin Ren, and Jing-yuan Zhang Copyright © 2015 Wen-yi Huo et al. All rights reserved. Fabrication and Characterization of Nickel Chloride Doped PMMA Films Thu, 01 Jan 2015 13:55:59 +0000 Films of PMMA and PMMA doped with NiCl2 with different contents were prepared using the casting technique. The optical properties of all films were investigated using spectrophotometric measurements of absorbance and transmittance in the wavelength range 200–800 nm. The change of the calculated values of the optical energy gaps with increasing NiCl2 content has been interpreted in terms of the structural modifications of the PMMA matrix. The optical energy gap decreased from 3.6 to 3.05 eV with increasing the NiCl2 concentration to 0.4%. The effect of doping on the optical constants of films such as refractive index, extinction coefficient, real and imaginary parts of dielectric constant, optical conductivity, and skin depth has been reported. All these constants were increased with increasing NiCl2 concentration with the exception of skin depth which is different result. Wasan A. Al-Taa’y, Saad F. Oboudi, Emad Yousif, Mohammed Abdul Nabi, Rahimi M. Yusop, and Darfizzi Derawi Copyright © 2015 Wasan A. Al-Taa’y et al. All rights reserved. Experimental and Theoretical Advances in Amorphous Alloys Wed, 31 Dec 2014 13:12:57 +0000 Na Chen, Limei Xu, Yang Shao, and Konstantinos Georgarakis Copyright © 2014 Na Chen et al. All rights reserved. Test Study on Airtight Capability of Filter Cakes for Slurry Shield and Its Application in a Case Wed, 31 Dec 2014 08:05:03 +0000 To learn the airproof capacity of filter cakes as opening chambers under air pressure, a series of tests were carried out. The variations of discharged water with air pressure and time were observed, and the relationship between airproof capacity of filter cakes and surrounding air pressure was analysed. The test results indicated that there were three stages as compressed air acting on filter cakes: completely not infiltration, a very small amount of infiltration, and penetration leakage. The certain air pressure between the first and second stages was called the airproofing value of filter cake. And a capillary bundle model was used to explain the mechanism of air tightness of filter cakes. In Nanjing Yangtze River Tunnel, a 5 cm thickness filter cake was formed in gravel sand, and its airproofing value was a little lower than 0.12 MPa. The air pressure used as opening chamber should be equal to the summation of water pressure in sand and airproofing value of filter cake. While the air pressure is larger than the summation, the filter cake would be gas permeable. The slurry formulation and airproofing value of filter cakes obtained in the tests were applied successfully in Nanjing Yangtze River Tunnel. Fanlu Min, Wei Zhu, Shengquan Xia, Rui Wang, Daiwei Wei, and Teng Jiang Copyright © 2014 Fanlu Min et al. All rights reserved. High Temperature Corrosion of Inconel 600 in NaCl-KCl Molten Salts Tue, 30 Dec 2014 08:39:24 +0000 In this work the corrosion resistance of a high content nickel alloy, Inconel 600, was investigated in mixed NaCl-KCl salts at 700, 800, and 900°C for 100 hours in static air. Investigation was carried out using electrochemical techniques such as polarization curves, rest potential measurements, linear polarization resistance, and electrochemical impedance spectroscopy. Corroded specimens were analyzed by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). Electrochemical measurements showed an increased degradation rate of Inconel 600 with increasing test temperature. SEM and EDS analysis show that the damage experienced by Inconel 600 is greater than that determined by electrochemical measurements. This damage was identified as internal corrosion due to the reaction of Cl2 with the alloying elements (Cr and Fe); however, at 900°C the internal damage was minor and it was associated with the nickel content in the alloy. G. Salinas-Solano, J. Porcayo-Calderon, J. G. Gonzalez-Rodriguez, V. M. Salinas-Bravo, J. A. Ascencio-Gutierrez, and L. Martinez-Gomez Copyright © 2014 G. Salinas-Solano et al. All rights reserved. Influences of Mg Doping on the Electrochemical Performance of TiO2 Nanodots Based Biosensor Electrodes Mon, 29 Dec 2014 00:10:33 +0000 Electrochemical biosensors are essential for health monitors to help in diagnosis and detection of diseases. Enzyme adsorptions on biosensor electrodes and direct electron transfer between them have been recognized as key factors to affect biosensor performance. TiO2 has a good protein adsorption ability and facilitates having more enzyme adsorption and better electron transfer. In this work, Mg ions are introduced into TiO2 nanodots in order to further improve electrode performance because Mg ions are considered to have good affinity with proteins or enzymes. Mg doped TiO2 nanodots on Ti substrates were prepared by spin-coating and calcining. The effects of Mg doping on the nanodots morphology and performance of the electrodes were investigated. The density and size of TiO2 nanodots were obviously changed with Mg doping. The sensitivity of 2% Mg doped TiO2 nanodots based biosensor electrode increased to 1377.64 from 897.8 µA mM−1 cm−2 and its decreases to 0.83 from 1.27 mM, implying that the enzyme achieves higher catalytic efficiency due to better affinity of the enzyme with the Mg doped TiO2. The present work could provide an alternative to improve biosensor performances. M. S. H. Al-Furjan, Kui Cheng, and Wenjian Weng Copyright © 2014 M. S. H. Al-Furjan et al. All rights reserved. Effects of Sb2O3 on the Mechanical Properties of the Borosilicate Foam Glasses Sintered at Low Temperature Sun, 28 Dec 2014 09:47:17 +0000 The physical properties and microstructure of a new kind of borosilicate foam glasses with different Sb2O3 doping content are comprehensively investigated. The experimental results show that appropriate addition of Sb2O3 has positive impact on the bulk porosity and compressive strength of the foam glass. It is more suitable in this work to introduce 0.9 wt.% Sb2O3 into the Na2O-K2O-B2O3-Al2O3-SiO2 basic foam glass component and sinter at 775°C. And the obtained foam glasses present much more uniform microstructure, large pore size, and smooth cell walls, which bring them with better performance including a lower bulk density, low water absorption, and an appreciable compressive strength. The microstructure analysis indicates that, with the increase of the content of Sb2O3 additives, the cell size tends to increase at first and then decreases. Larger amounts of Sb2O3 do not change the crystalline phase of foam glass but increase its vitrification. It is meaningful to prepare the foam glass at a relatively low temperature for reducing the heat energy consumption. Chenxi Zhai, Zhe Li, Yumei Zhu, Jing Zhang, Xiuduo Wang, Lejun Zhao, Liuming Pan, and Pengfei Wang Copyright © 2014 Chenxi Zhai et al. All rights reserved. Ammonothermal Synthesis and Photocatalytic Activity of Lower Valence Cation-Doped LaNbON2 Thu, 25 Dec 2014 00:10:25 +0000 Highly crystalline pure perovskite-type LaNbON2 powders were synthesized in supercritical ammonia using sodium hydroxide as an oxygen source. Additionally, doping LaNbON2 with cations of lower valence than that of the parent cation was performed to inhibit reduction of Nb5+. Various characterization methods indicated that crystallinity, particle morphology, and absorption edge of the product, that is, the factors possibly affecting photocatalytic activity, were not significantly changed by the doping of a lower-valence cation. Nevertheless, the doped LaNbON2 synthesized using the ammonothermal method evolved hydrogen, suggesting that this type of doping decreases the formation of reduced niobium species and consequently enhances the photocatalytic activity of LaNbON2. In case of doped LaNbON2 synthesized using conventional method, no hydrogen evolution was observed. This difference is probably due to the higher crystallinity of ammonothermally synthesized LaNbON2. Therefore, we successfully produced LaNbON2 with improved potential for photocatalytic activity for hydrogen evolution under visible light irradiation using ammonothermal synthesis and lower-valence cation doping. Chihiro Izawa, Takeshi Kobayashi, Kazuhisa Kishida, and Tomoaki Watanabe Copyright © 2014 Chihiro Izawa et al. All rights reserved. A New Mathematical Model for Flank Wear Prediction Using Functional Data Analysis Methodology Wed, 24 Dec 2014 11:26:03 +0000 This paper presents a new approach improving the reliability of flank wear prediction during the end milling process. In the present work, prediction of flank wear has been achieved by using cutting parameters and force signals as the sensitive carriers of information about the machining process. A series of experiments were conducted to establish the relationship between flank wear and cutting force components as well as the cutting parameters such as cutting speed, feed per tooth, and radial depth of cut. In order to be able to predict flank wear a new linear regression mathematical model has been developed by utilizing functional data analysis methodology. Regression coefficients of the model are in the form of time dependent functions that have been determined through the use of functional data analysis methodology. The mathematical model has been developed by means of applied cutting parameters and measured cutting forces components during the end milling of workpiece made of 42CrMo4 steel. The efficiency and flexibility of the developed model have been verified by comparing it with the separate experimental data set. Sonja Jozić, Branimir Lela, and Dražen Bajić Copyright © 2014 Sonja Jozić et al. All rights reserved. Effects of Additives and Sintering Time on the Microstructure of Ni-Zn Ferrite and Its Electrical and Magnetic Properties Wed, 24 Dec 2014 10:45:47 +0000 This work aims to investigate the relationship between the microstructure of Ni-Zn ferrite and its electrical and magnetic properties in the presence and absence of as small amounts as 0.12% of 0.4CaO + 0.8SiO2 over different sintering times. The X-ray diffraction pattern showed a single spinel phase formation in all the samples. The results indicate that grain growth occurred by increasing sintering time from 15 to 270 min in the two types of samples prepared in this study although it was greatly impeded by the additive oxides. Moreover, the oxides increase the resistivity of the ferrite and decrease its zinc loss. Magnetic properties such as induction magnetization () and saturation magnetization () decreased in the presence of the additives while its coercivity () increased. Finally, the density of the samples was observed to increase with increasing sintering time in both types of the samples but with a higher value in the samples with no additives. Abdollah Hajalilou, Mansor Hashim, and Halimah Mohamed Kamari Copyright © 2014 Abdollah Hajalilou et al. All rights reserved.