Characterisation of spray‐dried microparticles containing iron coated by pectin/resistant starch

Iron is one of three major minerals in human body. However, the iron deficiency is a medical problem in developed and underdeveloped countries due to its poor oral absorption or insufficient iron intake. Encapsulation could solve problems associated with oral iron consumption. Various advantages including low cost, biodegradability, biocompatibility and large‐scale production have been included in the current study. In a modified encapsulation method, iron microparticles were prepared using low methoxy pectin and resistant starch during spray drying. Covalent and hydrogen bonds were formed between iron and pectin and between polymers, respectively. Particles sized 3.5 ± 1.14 μm and showed spherical shapes. The yield of particles was 72.07%, and solubility and loading efficiency were 33.64% ± 0.88 and 34.79%, respectively. In conclusion, using iron as a cross‐linker of pectin molecules resulted in microparticles with appropriate properties of lowering organoleptic changes and a better bioavailability especially in dairy‐based products for food fortification.     

An empirical model for modified bituminous binder master curves

Modeling the mechanical behavior of asphalt binders and mixtures has been the subject of intensified research in recent decades. Master curves of the norm of the complex modulus |G*| in the linear viscoelastic domain are frequently used for modeling, while phase angle master curves are less frequently considered for this purpose. Therefore in this research, an empirical model is introduced for phase angle master curves of modified and neat bituminous binders. The model is based on a general form of a double-logistic (DL) mathematical function. The |G*| master curve was then modeled using a mutual relationship between the phase angle and |G*|. Master curves of three neat and seven modified binders were generated and used to validate the DL model. The results showed that the model is capable of properly predicting the plateau region of phase angle master curves. In particular, the asymptotic behavior of the master curves at high frequencies can be modeled correctly. The model also describes irregularities in the high temperature range of the phase angle master curve. In general, model outputs such as the phase angle value at the plateau, glassy modulus, rheological index and crossover frequency correctly predict the behavior of the neat and modified binders.     

Green polycarbonates prepared by the copolymerization of CO2 with epoxides

Polycarbonates can be prepared by the copolymerization of epoxides with carbon dioxide as an inexpensive, abundant, nontoxic, and renewable feedstock. This review covers the synthesis, the physicochemical properties, and the growing applications of this class of green polymers. The review has been conceived to provide a useful tool for the researchers who are new to this field, as well as to offer an updated overview for those who are already actively working on this topic. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41141.     

An erbium–organic framework as an adsorbent for the fast and selective adsorption of methylene blue from aqueous solutions

The applicability of erbium–metal–organic framework (Er-MOF) in the adsorption and removal of methylene blue from aqueous solution has been studied. Er-MOF was synthesized by hydrothermal method and characterized using Fourier transform infrared spectroscopy, scanning electron microscopy, and X-ray powder diffraction. The high thermal stability, water stability and accessible nano-sized aperture for the Er-MOF could endow it with a very high potential in adsorption of dye pollutant. The adsorption isotherm, kinetic and thermodynamic investigations confirm that the adsorption behavior is based on Langmuir isotherm with an exothermic mechanism and enthalpy-driven process. The speed adsorption process (30 min), low cost, high efficiency, big surface area, selectivity and very high and rapid reusability are the main advantages of the proposed compound as a sorbent.     

Kinetic modeling of mass transfer during deep fat frying of shrimp nugget prepared without a pre-frying step

The objective of this study was to evaluate the effect of different batter formulation on mass transfer during deep fat frying of shrimp nuggets prepared without a pre-frying step. The effects of soy and corn flour (5, 10%) addition to the batter formulation, frying temperature and time on mass transfer were determined. The results showed an interaction effect of these processing conditions on mass transfer. The most reduction in fat absorption was observed when samples were coated with batter contained 10% soy flour and fried at 190 °C. The first order kinetic based on the Fick's law were used to describe moisture transfer data. The effective moisture diffusivity ranged between 2.05 × 10⁻⁸ and 5.71 × 10⁻⁸ m²/s with R² between 0.91 and 0.98, and fat transfer rate constant was between 3.5 × 10⁻³ and 7.8 × 10⁻³ s⁻¹ with R² from 0.82 to 0.99. Activation energy obtained from the Arrhenius plot for the effective moisture diffusivity ranged between 18.42 and 23.84 kJ/mol.     

Ethanol and chitosan production from wheat hydrolysate by Mucor hiemalis

BACKGROUND: High glucose and ethanol tolerance is among the most important requirements of ethanol‐producing microorganisms. The purpose of this study was evaluation of filamentous fungus Mucor hiemalis for ethanol production from wheat and starch hydrolysates with high glucose concentration. RESULTS: The results showed high tolerance of the fungus in fermentation of the hydrolyzates with high glucose concentrations (as high as 190 g L^?1). Interestingly, increasing the glucose concentration from 15 to 190 g L^?1 was accompanied by enhancement of initial sugar uptake rate. Ethanol was the most important metabolite obtained during all fermentations and its concentration reached over 50 g L^?1. Beside ethanol, chitosan was another valuable product of the process. Glucosamine, a precursor of chitosan, made up 37.3–46.7% of the cell wall of this fungus. CONCLUSIONS: M. hiemalis is a promising microorganism for simultaneous production of ethanol and chitosan from substrates with high sugar concentrations. © 2012 Society of Chemical Industry     

Kinetic Study of Sodium Cocoyl Sarcosinate Synthesis and Factors Affecting the Reaction on Bench and Pilot Scales

Sodium cocoyl sarcosinate is an important surfactant with a particular chemical structure and many practical applications in various industries. The synthesis of sodium cocoyl sarcosinate involves the reaction of cocoyl chloride and N-methyl glycine. The influences of reactant molar ratios, temperature, reaction time, pH, and solvent on the reaction yield were investigated and also the kinetics of the reaction was studied. It was found that the reaction follows second order kinetics and the reaction rate constant is 0.0153?mol^?1?L?s^?1 at 35?°C. Also production of sodium cocoyl sarcosinate was carried out at bench and pilot scales which is described in details.     

A developed single-phase cascaded multilevel inverter with reduced number of circuit devices

In this paper, an advanced configuration for multilevel voltage source inverters is proposed. The proposed topology can be used as symmetric and asymmetric inverter. In asymmetric mode, DC sources’ magnitudes are defined in a way that the number of output voltage levels gets more than the case when the symmetrical DC sources are applied. In this regard, to calculate the magnitudes of required DC voltage sources, several different solutions are proposed. In multilevel inverters, the overall cost, circuit size and so installation area, complexity of control scheme and reliability are directly dependent on the number of circuit devices needed. The provided comparison study among suggested inverter in all defined solutions, CHB and recently proposed converters validates that the proposed modular inverter uses reduced number of circuit devices. The provided simulation and experimental results confirm the feasibility of the proposed structure and show that the obtained results are in good agreements.     

Numerical and Experimental Biomass Separation from Fermentation Process by Minihydrocyclones

Biomass particle separation is challenging in the pharmaceutical industry because of the smallness and lightness of such particles. Centrifugation is applied conventionally for batch separation. However, imposing multiple wash steps in order to eliminate culture residues and the high risk of extrinsic contamination hamper batch techniques. In this research, minihydrocyclones were introduced to provide a better solution for the mentioned limitations in continuous processes. Numerical separation of methylotrophic yeast from fermentation broth was carried out in three hydrocyclones with different lengths, and the most efficient one was examined experimentally. Three various feed flow rates and seven feed concentrations were evaluated. The concentration of biomass suspension in the product was raised to 20 %.     

Four Novel p.N385K,p.V36A,c.1033–1034insT and c.1417–1418delCT Mutations in the Sphingomyelin Phosphodiesterase 1 (SMPD1) Gene in Patients with Types A and B Niemann-Pick Disease (NPD)

Background: Types A and B Niemann-Pick disease (NPD) are autosomal-recessive lysosomal storage disorders caused by the deficient activity of acid sphingomyelinase due to mutations in the sphingomyelin phosphodiesterase 1 (SMPD1) gene. Methods: In order to determine the prevalence and distribution of SMPD1 gene mutations, the genomic DNA of 15 unrelated Iranian patients with types A and B NPD was examined using PCR, DNA sequencing and bioinformatics analysis. Results: Of 8 patients with the p.G508R mutation, 5 patients were homozygous, while the other 3 were heterozygous. One patient was heterozygous for both the p.N385K and p.G508R mutations. Another patient was heterozygous for both the p.A487V and p.G508R mutations. Two patients (one homozygous and one heterozygous) showed the p.V36A mutation. One patient was homozygous for the c.1033–1034insT mutation. One patient was homozygous for the c.573delT mutation, and 1 patient was homozygous for the c.1417–1418delCT mutation. Additionally, bioinformatics analysis indicated that two new p.V36A and p.N385K mutations decreased the acid sphingomyelinase (ASM) protein stability, which might be evidence to suggest the pathogenicity of these mutations. Conclusion: with detection of these new mutations, the genotypic spectrum of types A and B NPD is extended, facilitating the definition of disease-related mutations. However, more research is essential to confirm the pathogenic effect of these mutations.