Anthocyanins characterization of 15 Iranian pomegranate (Punica granatum L.) varieties and their variation after cold storage and pasteurization

Anthocyanins (ACs) are phenolic compounds that are distributed widely in fruits and vegetables. Apart from imparting color to plants, ACs also have an array of health-promoting benefits. In this research, the amounts of major ACs of 15 pomegranate (Punica granatum L.) varieties obtained from Yazd province were determined. The major ACs detected in the studied varieties were as follows: delphinidin 3-glucoside (2.19–16.29 mg/L), delphinidin 3,5-diglucoside (2.36–63.07 mg/L), pelargonidin 3-glucoside (0.26–1.36 mg/L), pelargonidin 3,5-diglucoside (0.01–8.11 mg/L), cyanidin 3-glucoside (5.78–30.38 mg/L), and cyanidin 3,5-diglucoside (4.39–166.32 mg/L). The effect of storage time of unprocessed and pasteurized juices on ACs content of four selected varieties was also studied. Average degradation percentage of each AC was between 23.0 and 83.0% during 10 days at 4 °C. Moreover, in pasteurized juices average degradation of ACs was 42.8 ± 0.5% after 10 weeks storage at 4 °C.     

Improved physical stability of docosahexaenoic acid and eicosapentaenoic acid encapsulated using nanoliposome containing α‐tocopherol

This study aimed to develop a nanoliposomal formulation containing α‐tocopherol loaded with eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) and to characterise the formulation by its physical stability. For this purpose, different nanoliposomal formulations with dipalmitoyl phosphocholine were prepared using a modified thin‐film hydration method and evaluated by particle size, polydispersity index (PDI), transmission electron microscopy, differential scanning calorimetry and determining the encapsulation efficiencies of DHA and EPA. A physical stability study was conducted by investigating the change in the vesicle encapsulation efficiency, particle size, PDI and shape when stored at 4, 30 and 40 °C for 3 months. High encapsulation efficiency of DHA and EPA (89.1% ± 0.6% and 81.9% ± 1.4%) and appropriate particle size (82 ± 0.8 nm) were obtained for liposomes composed of α‐tocopherol. The optimum formulation was stable for 90 days when kept at 4 °C. This study demonstrated that α‐tocopherol had a protective effect on the physical stability of the nanoliposomes containing DHA and EPA.     

Comparison of Canola and Soy Flour with Added Isocyanate as Wood Adhesives

Canola is widely grown in the northern latitudes for its vegetable oil, generating large quantities of residual, low value canola flour used as animal feed. The common wood adhesive poly(diphenylmethylene diisocyanate) (pMDI) should react with the wide variety of functional groups in proteins. Therefore, it would seem that canola flour with added pMDI could be an effective adhesive. Two main questions are addressed in this study: How do the wood adhesive properties of canola flour compare to the better-studied soy flour? How well do proteins, which contain an abundance of functional groups, cure with the very reactive pMDI? These questions were addressed using the small-scale adhesive strength test ASTM D-7998, with various adhesive formulations and bonding conditions for canola flour plus pMDI compared to soy adhesives. The more challenging wet cohesive bond strength was emphasized because the dry strengths were usually very good. Generally, soy adhesives were better than canola ones, as was the polyamidoamine-epichlorohydrin cross-linker compared to pMDI, but these generalizations can be altered by the conditions selected. Three-ply plywood tests supported the small-scale test results.     

An Investigation of the Effect of Sintering Conditions on the Mechanical Behavior of Electroplated Nickel Foams

Metallurgical and Materials Transactions B - This study investigates the effect of sintering temperature on the compression strength of nickel foams in an inert atmosphere. The nickel foams were...     

The TiO2–Clay-LDPE Nanocomposite Packaging Films: Investigation on the Structure and Physicomechanical Properties

The role of nanoclays and TiO₂ nanoparticle loadings were investigated on low density polyethylene crystalline structure, in addition to studying packaging film properties such as barrier, thermal and mechanical properties. The polymer crystal study indicated for the orthorhombic crystal phase and about 20% lower degree of crystallinity for nanocomposites containing more than 2 wt.% TiO₂ nanoparticles. Based on the X-ray diffraction technique, the dispersion of nanoclays was improved to almost good degree of clay exfoliation with the company of 4 wt.% TiO₂ nanoparticles. In agreement with XRD results, the TEM morphological studies mainly suggest that TiO₂ has a helpful effect on nanoclay exfoliation. The increase in degradation temperature of nanocomposites may be attributed to the formation of inorganic char on polymer melt. The barrier properties of TiO₂/clay nanocomposite packaging films depend mainly on nanoclay loading with an unclear trend from TiO₂ nanoparticles. The increase in elastic modulus and the yield stress of nanocomposite films showed great effects on film mechanical properties by nanoclays.     

Efficient Synthesis of α-Monoglycerides via Solventless Condensation of Fatty Acids with Glycerol Carbonate

Highly pure α-monoglycerides (5a–e) were successfully prepared in high yields by the condensation of fatty acids such as lauric, myristic, palmitic, stearic and oleic (2a–e) with glycerol carbonate (4-hydroxymethyl-1,3-dioxolan-2-one) (1) in the presence of triethylamine as catalyst. Reaction conditions and spectroscopic identification of products will be presented in this article.     

Modified chitosan as a polymeric nanoreactor for fabrication of pure ZnO nano particles

ZnO nanoparticles have been prepared successfully by hydrogel decomposition method (HDM). Synthesized ZnO nanoparticles were characterized by X‐ray diffraction (XRD), fourier transforms infrared spectroscopy (FTIR), and transition electron microscopy (TEM) techniques. Narrow distribution of sizes with a 20–30 nm diameter and regular distribution of ZnO nanoparticles are attributed to the application of poly(acrylic acid‐co‐acrylamide) grafted chitosan hydrogel as coating agent. The results show that the polymer thermal decomposition technique is a perfect method for the synthesis of ZnO nanoparticles. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Thermo‐economic‐environmental multiobjective optimization of a gas turbine power plant with preheater using evolutionary algorithm

In this study, the gas turbine power plant with preheater is modeled and the simulation results are compared with one of the gas turbine power plants in Iran namely Yazd Gas Turbine. Moreover, multiobjective optimization has been performed to find the best design variables. The design parameters of the present study are selected as: air compressor pressure ratio (r_AC), compressor isentropic efficiency (η_AC), gas turbine isentropic efficiency (η_GT), combustion chamber inlet temperature (T₃) and gas turbine inlet temperature. In the optimization approach, the exergetic, economic and environmental aspects have been considered. In multiobjective optimization, the three objective functions, including the gas turbine exergy efficiency, total cost rate of the system production including cost rate of environmental impact and CO₂ emission, have been considered. The thermoenvironomic objective function is minimized while power plant exergy efficiency is maximized using a genetic algorithm. To have a good insight into this study, a sensitivity analysis of the results to the interest rate as well as fuel cost has been performed. In addition, the results showed that at the lower exergetic efficiency in which the weight of thermoenvironomic objective is higher, the sensitivity of the optimal solutions to the fuel cost is much higher than the location of Pareto Frontier with the lower weight of thermoenvironomic objective. Copyright © 2010 John Wiley & Sons, Ltd.     

Dendrigraft with citric acid on acrylonitrile/acrylic acid copolymer electrospun fibres

Acrylonitrile/acrylic acid copolymers were synthesized with different mole fractions (1, 2, 5 and 10 mol%) of acrylic acid (AA) in the feed by aqueous suspension polymerization, and bead‐free fibres (295–375 nm in diameter) were made from the copolymers in dimethylformamide solutions by electrospinning. In a heterogeneous system containing electrospun fibre mats, dendritic molecules were grown by reaction between carboxylic acid of AA and –OH groups of citric acid activated by dicyclohexylcarbodiimide. The products were analysed using ¹H NMR, ¹³C NMR and Fourier transform infrared spectroscopies, density determination, scanning electron microscopy, optical microscopy, differential scanning calorimetry and pH response properties. With decreasing AA content, the isotacticity of the copolymers decreases with a more random distribution of the co‐monomers which leads to higher percentage conversions of dendrigraft due to reduced steric hindrance. On the formation of dendrigraft, the percentage conversion of the reactions decreases with an increase of generation number and AA content. A reduction of density for the first generation and then an increase with increasing generation are observed. During oxidation stabilization of fibres with a decrease of AA content and an increase in generation number, the amount of liberated heat increases. Fibres containing more carboxylic groups show significantly greater amounts of swelling/de‐swelling in basic and acidic media, respectively. To be used as nanocarbon fibre precursors, or as active particles for loading with guest molecules, or as pH actuators, the first generation of dendrigrafted fibres are expected to have the greatest potential among the various samples examined. © 2013 Society of Chemical Industry