Characterization of Erbium,Indium, and Erbium–Indium co-doped 8%mol Yttria-stabilized Zirconia

Journal of Materials Science: Materials in Electronics - In this work, the cubic structure of Yttria-stabilized Zirconia (8YSZ) and Indium and Erbium co-doped 8YSZ nanopowders have been prepared by...     

Development of healthy extruded maize snacks; Effects of soybean flour and feed moisture content

The main aim of this research was to introduce a green and clean method of increasing the nutritional quality while preserving the quality of extruded maize snacks. This was achieved by addition of soybean flour (5%, 10%, 15% and 20%, w/w) as a source of plant protein, fibre and bioactive compounds and changing the feed moisture content. Extruded samples were produced using a single-screw extruder. Increasing the soybean flour and feed moisture content resulted in reduced specific mechanical energy of the extruder and consequently several changes in physicochemical properties of the snacks including higher moisture content, lower expansion and volume, reduced crispiness, reduction in L-and a-values but an increase in b-value and formation of more wrinkly and thicker air bubbles cell walls as observed under scanning electron microscope. The addition of <20% soybean flour and feed moisture content resulted in snacks with improved nutritional value and physical properties.     

Novel inexpensive transition metal phosphide catalysts for upgrading of pyrolysis oil via hydrodeoxygenation

Supported molybdenum/molybdenum‐phosphides as inexpensive catalysts for bio‐oil hydrodeoxygenation (HDO) were in‐house prepared using different support materials, i.e., Al₂O₃, activated carbon (AC), MgAl₂O₄, and Mg₆Al₂(CO₃)(OH)₁₆. The HDO activity of these catalysts were investigated using a 100 mL bench‐scale reactor operating at 300°C with an initial hydrogen pressure of 50 bar for 3 h with a pyrolysis oil (PO). The catalytic efficiencies for bio‐oil HDO for the catalysts were compared with the expensive but commercially available Ru/C catalyst. Addition of small amount of P to the Mo catalysts supported on either AC and Al₂O₃ led to increased degree of deoxygenation (DOD) and oil yield compared with those without P. MoP supported on AC (MoP/AC) demonstrated bio‐oil HDO activity comparable to the Ru/C catalyst. Furthermore, three AC‐supported metal phosphides for PO HDO were compared under the same conditions, and they were found to follow the order of NiP/AC > CoP/AC > MoP/AC. © 2016 American Institute of Chemical Engineers AIChE J, 62: 3664–3672, 2016     

Experimental evaluation of seismic performance of low‐shear strength masonry infills with openings in reinforced concrete frames with deficient seismic details

The influence of openings on lateral behaviour of low‐shear strength masonry infilled reinforced concrete frames is investigated. The design of the reinforced concrete frames in this study are aimed to reflect common seismic design deficiencies, such as location of lap splices at bottom of columns, insufficient transverse reinforcements at column and beam ends and lack of stirrups at beam‐column joints. Six half‐scale single‐storey, single‐bay frame specimens were tested under in‐plane lateral loading. The investigated parameters include shape (window and door), size (regular and large windows) and location of the openings (eccentric and central). The results indicate that presence of openings alters the failure mode, increases the damage level and reduces ductility, strength and stiffness of the infilled frame. The door opening led to reductions of 29% in strength, 34% in the effective stiffness and 23% in the energy dissipation capacity. The window openings led to average reductions of 23% in strength, 8% in effective stiffness and 11% in the energy dissipation capacity. Empirical equations are proposed for estimating overall reductions in stiffness and strength of infilled frames because of the presence of openings, which take into account the effects of size, shape and location of openings. Copyright © 2013 John Wiley & Sons, Ltd.     

Modeling and simulation of air-gapped current transformer based on Preisach Theory

Current Transformer (CT) modeling, by which CT’s characteristics can be studied has a significant importance in CT selection and design. In spite of numerous studies about closed-core CT model, only a few works have been conducted on air-gapped ones with the following problems: models of which required data is easily-accessible, have poor simulations of magnetization process; on the contrary, models which have satisfactory simulations, are hard to be established because of the hard-to-get required data. Therefore, based on Preisach Theory, a novel air-gapped CT model is deduced from the closed core CT model. The proposed model is accurate and can be established easily. The saturation and remanence properties of closed-core CT and air-gapped CT are simulated and compared.     

Preparation of Tethered Half-Titanocene Complex on Syndiotactic Poly(styrene-<Emphasis Type="Italic">co</Emphasis>-<Emphasis Type="Italic">p</Emphasis>-methylstyrene) for Using in Syndiospecific Polymerization of Styrene

Abstract  

In this work the syndiotactic polystyrene copolymer, poly (styrene-co-p-methylstyrene) was prepared by the copolymerization of styrene and p-methylstyrene with cyclopentadienyltitanium trichloride/methylaluminoxane catalyst. This copolymer was functionalized with silyl-hydride groups. The structure of copolymer and functionalized copolymer were characterized by FT-IR, ¹H-NMR and ¹³C-NMR spectroscopy. The obtained results revealed that the functionalization reaction successfully proceeds at low temperatures. Tethering of half-titanocene complex on polymeric support was done by the hydrosilylation reaction of 1-allylindenyltrichlorotitanium with silyl-hydride functionalized copolymer in the presence of Karstedt catalyst as a coupling reagent. The polymer-supported catalyst was tested for syndiospecific polymerization of styrene using methylaluminoxane as a cocatalyst. The results of styrene polymerization showed that the polymer-supported catalyst exhibited high activity for syndiospecific polymerization of styrene. The polymer prepared with supported catalyst was characterized by carbon nuclear magnetic resonance (¹³C-NMR) and differential scanning calorimetry (DSC). The results confirmed the syndiotacticity of obtained polymers. X-ray diffraction (XRD) analysis showed the δ-form crystalline structure of obtained syndiotactic polystyrene.     

Using Coal Fly Ash and Wastewater for Microwave Synthesis of LTA Zeolite

The reuse of industrial wastes from a coal‐fired power plant and a plasma electrolytic oxidation process was attempted to realize a zero discharge. The batch composition was adjusted by adding sodium hydroxide and sodium aluminate. A single‐mode microwave oven equipped with reflux condenser was used for crystallization under atmospheric pressure. The synthesized samples were characterized by X‐ray diffraction, scanning electron microscopy, BET, thermogravimetric analysis, and cation‐exchange capacity (CEC) measurement. Analytical results indicated that Na‐A zeolite with a defined maximum crystallinity could be successfully synthesized by hydrothermal treatment of fly ash with wastewater. Due to the high CEC, the product can be applied for gas purification and soil remediation processes.     

Prediction of Air Specific Heat Ratios at Elevated Pressures Using a Novel Modeling Approach

An accurate and efficient model based on least‐squares support vector machines (LSSVM) is developed for the determination of air specific heat ratios at elevated pressures. Additionally, the coupled simulated annealing optimization strategy is used to calculate the optimal values of the LSSVM parameters. A large dataset of air specific heat ratios as a function of temperature and pressure for about 170 samples is used to develop and validate the model. The leverage approach (Williams plot) is used to determine the applicability domain of the model and to detect probably erroneous data points. Comparison of the obtained results with a previously published correlation as well as an intelligent method demonstrates that the performance of the presented model is more satisfactory than that of other methods.     

Effects of different filling media on the oxidation and lipid quality of canned silver carp (Hypophthalmichthys molitrix)

The influence of four different filling media (sunflower oil, soybean oil, olive oil and brine) on the oxidation and lipid quality of canned silver carp was evaluated. Hydrolytic rancidity showed that free fatty acid contents in brine and soybean oil canned muscle were higher than olive oil or sunflower oil canned samples. Conjugated diene (CD) levels in soybean oil canned samples increased but the highest CD values were found in canned silver carp using brine as filling medium. Except for olive oil canned muscle, significant increase in thiobarbituric acid (TBA) values was obtained. The highest TBA value was observed in soybean oil canned sample. Canning led to exchange of fatty acids between the fat in the silver carp muscle and the filling media used. Results indicate that the fat composition of canned silver carp tends to be similar to that of the fat used as filling media.     

CALCULATING PSEUDO-STEADY-STATE HORIZONTAL OIL WELL PRODUCTIVITY IN RECTANGULAR DRAINAGE AREAS USING A SIMPLE METHOD

To determine the economical feasibility of drilling a horizontal well, engineers need reliable methods to estimate its productivity. In this work, a simple-to-use method is developed to rapidly estimate a pseudo-steady-state horizontal well's productivity. Estimations are found to be in excellent agreement with the reliable data in the literature, with average absolute deviation being less than 1%. The tool developed in this study can be of immense practical value for petroleum engineers to make a quick check on a pseudo-steady-state horizontal well's productivity at various conditions without opting for any field trials. The predictive tool is simple and straightforward, and it can be readily implemented in a standard spreadsheet program. The prime application of the method is as a quick-and-easy evaluation tool in conceptual development and scoping studies where horizontal wells are being considered. The method may also serve as a benchmark in numerical reservoir simulation studies.