Crystallographic parameters and electro-optical constants in ITO thin films

Indium tin oxide thin films were deposited onto soda lime glass substrates using an e-beam evaporation system. In order to improve the structural, electrical and optical properties, the films were annealed at 450 °C and 500 °C in vacuum for 1 h. X-ray diffractions of samples were analyzed by Rietveld refinement and Warren–Averbach methods. By application of Levenberg–Marquardt least square method, the experimental transmittance data were fitted completely with the transmittance data calculated via a combination of modified Drude and Forouhi–Bloomer models. Focusing on the results, it was shown that the samples had a nanosize crystallite and enhancement of the annealing temperature resulted in an increase in the conductivity, carrier concentration, lattice parameter, crystallite size and micro-strain. However, it was found that the defects were preferentially accumulated along grain boundaries in sample annealed at lower temperature. Moreover, the finding revealed that conductivity of the samples was dominated by intra-grain in indium tin oxide films. Furthermore, increasing annealing temperature resulted in the orientation in < 111> crystal texture and also brought in an additional Burstein–Moss shift.     

Synthesis of Er2O3 Nanoparticles and Er2O3 Nanoparticle/Polyaniline Deposition on the Surface of Stainless Steel by Potentiostatic Deposition

Erbium oxide nanoparticles (Er₂O₃ NP) were synthesized with an efficient method in the presence and absence of sodium dodecylsulfate (SDS) as surfactant. The effect of SDS on the morphology of the synthesized Er₂O₃ NP is described. The NP were studied through scanning electron microscopy and X‐ray diffractometry. Then, polyaniline and a hybrid material of polyaniline/Er₂O₃ NP were deposited directly on a stainless steel wire by the potentiostatic process. The electrochemical data and scanning electron microscopic studies of polyaniline and its nanocomposite on the stainless steel wire demonstrate the influence of the synthesized Er₂O₃ NP on the electrodeposition of polyaniline. The presence of NP in the electrolyte solution during electrodeposition of polyaniline creates a nanocomposite with a more porous structure than pure polyaniline.     

Performance, carcass traits, muscle fatty acid composition and meat sensory properties of male Mahabadi goat kids fed palm oil, soybean oil or fish oil

This study examined the effect of palm, soybean or fish oils on the performance, muscle fatty acid composition and meat quality of goat kids. Twenty-four male Mahabadi kids (BW=19.4±1.2kg) were divided into three groups according to liveweight and randomly allocated to one of three diets. Animals were fed ad libitum for 84days. Different dietary fat sources had no effect on performance and/or carcass quality attributes. The soybean oil diet decreased 16:0 and 18:0 concentrations and increased 18:2 and 18:3 and the ratio of PUFA/SFA in the muscle compared with other treatments. Fish oil feeding increased 20:5 n-3 and 22:6 n-3 concentrations and decreased the ratio of n-6/n-3 in the muscle. The results demonstrate that the use of fish oil is a nutritional strategy to improve the health claimable long-chain omega-3 fatty acid content and n-6/n-3 ratio in goat meat without changing the sensory properties or colour of meat.     

Effect of Ca and Rare Earth Additions on the Texture,Microhardness, Microstructure and Structural Properties of As-Cast Mg–4Al–2Sn Alloys

In this work, alloys with nominal composition of Mg–4Al–2Sn–xRE–yCa (where RE = rare earth, x = 0, 1, 3 and y = 0, 1) have been prepared using tilt casting method. Prepared as-cast samples have been investigated by X-ray diffractometry, optical microscopy and scanning electron microscopy techniques as well as hardness measurement. The texture, microstructure and structural parameters of samples were also refined from X-ray diffraction patterns utilizing the Rietveld method and generalized spherical-harmonic model. It was found that with addition of rare earth and calcium elements, intermetallic phases of γ-Mg₁₇Al₁₂ and β-Mg₂Al₃ disappeared in cast alloys while small amount of Al₁₁RE₃ and CaMgSn intermetallics phases are formed. The texture factor of α-Mg as a main phase of samples was decreased with addition of rare earth up to 1 % and increased with more addition of rare earth elements. According to the results, with addition of rare earth elements, texture of Mg phase changes from 〈112〉 direction to 〈100〉 and 〈002〉 directions while Ca addition causes the texture in 〈002〉 direction. The microhardness of Mg–4Al–2Sn alloy was enhanced with addition of rare earth and calcium elements which is in agreement with the expected trend based on computed phase fraction of the samples. Addition of 1 wt% of calcium causes a dramatic change in the morphology and chemical composition of intermetallic phases, from acicular shape with composition of Al₁₁RE₃ into fine feather of CaMgSn intermetallic phase which accumulated in cluster morphologies in interdendritic regions.     

Kinetic modeling of oxidative coupling of methane over Mn/Na2WO4/SiO2 catalyst

A comprehensive kinetic model for oxidative coupling of methane (OCM) on Mn/Na₂WO₄/SiO₂ catalyst was developed based on a microcatalytic reactor data. The methane conversion and ethylene, ethane, carbon monoxide and carbon dioxide selectivities were obtained in a wide range of operating conditions including 750 < T < 875 °C, 4 < CH₄/O₂ < 7.5 and space time between 30 and 160 kg · s/m³ at P = 657 mmHg. The reaction networks of five kinetic models with appropriate rate equation type were compared together. The kinetics rates parameters of each reaction network were estimated using genetic algorithm optimization method. After comparing the reaction networks, the reaction network presented by Stansch et al. was found to best represent the OCM reaction network and was further used in this work. This kinetic network considers both catalytic and gas-phase as well as primary and consecutive reaction steps to predict the performance of the OCM. Comparing the experimental and predicted data showed that presented model has a reasonable fit between the experimental data and the predicted values with average absolute relative deviation of ± 9.1%.     

Synthesis,characterization, and drug‐release behavior of novel PEGylated bovine serum albumin as a carrier for anticancer agents

To develop a novel pH‐sensitive PEGylated carrier for protein‐based anticancer agents, we modified bovine serum albumin (BSA) with poly(ethylene glycol) citrate ester (PEG–CA) through amidation with its amino groups. Increasing the mixing ratio of albumin from 3 to 6 with respect to PEG–CA resulted in a 2‐fold increase in the degree of albumin modification. Adriamycin (ADR)‐loaded PEG–CA–BSA hydrogels and microparticles were prepared, and the cumulative amounts of ADR released from the PEG–CA–BSA hydrogels (phosphate‐buffered saline, pH 7.4) showed that all the PEG‐CA‐BSA_(x) (x represents degree of substitution of PEG to amino group of albumin, i.e. 26%, 28%, 31% and 49%) hydrogels had lower ADR release rates with a slight initial burst release. During the first 24 h, the cumulative releases were 15.5% for PEG–CA–BSA₍₄₉₎, 24% for PEG–CA–BSA₍₃₁₎, 31% for PEG–CA–BSA₍₂₈₎, and 38% for PEG–CA–BSA₍₂₆₎. Afterward, all the release rates slowed, and they were almost in the following order: PEG–CA–BSA₍₂₆₎ > PEG–CA–BSA₍₂₈₎ > PEG–CA–BSA₍₃₁₎ > PEG–CA–BSA₍₄₉₎. The release rates of ADR from the microparticles were dependent on the amount of glutaraldehyde. According to our findings, a higher PEG–CA/BSA molar ratio led to a reduced cumulative amount of ADR released from the hydrogels, whereas higher release rates were observed for microparticles with a lower amount of BSA in the conjugates in a pH‐dependent manner. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011