A Comparative Study on Changes and Relationships of Kernel Biochemical Components in Different Types of Maize

A great deal of genetic variability and breeding efforts have yielded a number of specialty maize types. Little is known about how the off‐target traits in specialty maize kernel have changed and how they compare to those of standard maize genotypes. In this study, we compared the normal (NORMAL), high‐oil (HOM) and high‐protein maize (HPM) genotypes in terms of oil, protein, fatty acids and some mineral components. We also investigated the relationships among the evaluated traits in different kernel types. We detected a significant variation among the maize types for all of the investigated traits. Specialty maize genotypes had a superior performance for the traits they were specifically bred for, as well as kernel mineral content over the normal genotypes. HOM and HPM had similar values in terms of their fatty acid composition. However, they were different from the standard genotypes, with higher oleic and lower linolenic acid levels, which indicates that the specialty maize genotypes possess a better oil quality. Correlation analysis revealed that only three pairs of correlations out of 46 values had the same sign and a similar level of significance in different types. Such similarities or differences in correlation values for different types should be taken into account in the efforts for developing high quality maize genotypes.     

An artificial neural network model for the prediction of critical submergence for intake in a stratified fluid medium

Density differences may occur because of temperature differentials, suspended sediments, dissolved salts or other chemicals. Most of the large surface reservoirs are stably stratified throughout most, or all, of the year. One of the means of assisting the management is to allow a selective withdrawal from the reservoir. And while an intake is used for withdrawal (from the lower layer), a maximum discharge is required not allowing the uptake of the upper layer fluids. The value of the intake's vertical distance from the upper layer elevation (submergence) when the upper layer fluids begin to be drawn into the intake is known as ‘critical submergence’. In this study, the critical submergence for a circular intake pipe in a stratified body (which has different layer thickness) is investigated. Experiments were conducted on a vertically flowing downward intake pipe in a still-water reservoir. Artificial neural network (ANN) models and formulas, which are found by the theoretical analysis of critical spherical sink surface (CSSS), are used for the analysis of experimental results. The CSSS has the same centre and discharge as the intake. The ANN model and CSSS results are compared with the experimental results.     

Adsorption of lead and copper on bentonite and grapeseed activated carbon in single- and binary-ion systems

In this study, bentonite originating from Turkey (Eski?ehir province) and activated carbon obtained from grapeseed were used as adsorbents for the removal of lead (Pb²⁺) and copper (Cu²⁺) ions from aqueous solutions. Experiments were performed in single- and binary-ion systems at constant temperature of 298 K and pH value of 5. In order to describe the adsorption mechanism Langmuir, Freundlich and Temkin isotherms were used. The total adsorption capacity values of adsorbents were compared. It was observed that the total adsorption capacity values were changed depending on the type of adsorbent used, type of metal ion and interaction between metal ions.     

Novel colloidal nanofiber electrolytes from PVA‐organoclay/poly(MA‐alt‐MVE), and their NaOH and Ag‐carrying polymer complexes

Novel multifunctional polymer nanofiber electrolytes with covalence crosslinked structures from various solution blends of reactive intercalated poly(vinyl alcohol)/octadecylamine montmorillonite (as a matrix polymer), poly(maleic anhydride‐alt‐methyl vinyl ether) (as a partner polymer) and their NaOH‐absorbing and Ag‐carrying polymer complexes were fabricated via electrospinning. Chemical, physical, morphological, and electrical properties of nanofiber structures were investigated by FTIR, XRD, SEM, and electrical analysis methods. Ag precursors in fiber composites significantly improved phase separation processing, fiber morphologies, diameter distributions, and electrical properties of the fibers. In situ generation of Ag nanoparticles and their distribution on nanofiber surfaces during fiber formation occurred via complex formation between silver cations and electronegative functional groups from both matrix and partner polymers as stabilizing/reducing agents. Electrical resistance and conductivity strongly depended on matrix/partner polymer ratios and absorption time of NaOH solution on nanofibers. Addition of NaOH changed the electrical properties of fiber structures from almost dielectric state to excellent conductivity form. The fabricated unique nanofiber electrolytes are promising candidates for applications in power and fuel cell nanotechnology, electrochemical, and bioengineering processes as reactive semiconductive platforms. POLYM. ENG. SCI., 56:204–213, 2016. © 2015 Society of Plastics Engineers     

Synthesis,characterization and polymerization of novel sugars based on methacrylate

The present study describes the synthesis and characterizations of polymerizable vinyl sugars. Glucose, mannose, galactose and fructose are abundant and sustainable natural compounds. As it is not possible to make many derivatives of sugars without using protective groups, first of all, diacetone derivatives [diacetone-d-glucose (1), diacetone-d-mannose (2), diacetone-d-galactose (3) and diacetone-d-fructose (4)] were synthesized according to the literature as starting compounds. The remaining free hydroxyl groups on C-3 (diacetone glucose), C-6 (diacetone galactose), C-1 (diacetone fructose) and C-1 (diacetone mannose), were reacted with epichlorohydrin (1-chloro-2,3-epoxypropane) to produce then “-O-(2′,3′-epoxypropane-1′-yl)” ether derivatives (5, 6, 7, and 8) which are epoxy sugars in the basic medium. Next, the epoxy rings of the ethers (5, 6, 7, and 8) were opened with methacrylic acid in DMF to produce new sugar based methacrylates (9, 10, 11, and 12). Finally, free radical polymerization of these sugar based methacrylate monomers was performed, producing related polymers (13, 14, 15 and 16). The polymerizations were carried out using AIBN as an initiator at 70 °C in DMF. All the products were characterized by FTIR, ¹HNMR and ¹³CNMR techniques. Thermal properties of all polymers were investigated by TG, DTG and DSC. The data obtained has suggested that thermal stability of the synthesized polymers has changed with the structure of the sugar and increase in molecular weight.     

Phase Transfer Catalysis with Quaternary Ammonium Type Gemini Surfactants: <Emphasis Type="Italic">O</Emphasis>-Alkylation of Isovanillin

In this paper, O-alkylation of isovanillin with unusual phase transfer catalysts alkandiyl-α,ω-bis(dimethylalkylammonium bromide) dimeric surfactants (also known as gemini surfactants) is described. Some dimeric surfactants with simple hydrophobic alkyl chains and others with hydrophobic alkyl chains containing ester functionalities with different lengths were synthesized and characterized in our laboratory. The alkylation of isovanillin with alkyl halide was successively carried out in the presence of potassium carbonate and a phase transfer catalyst in tetrahydrofuran. The same reactions were also performed with both the traditional phase transfer catalyst tetrabutylammonium bromide and without any catalyst. The results were compared with those of dimeric surfactants. Consequently, it was expressed that alkandiyl-α,ω-bis(dimethylalkylammonium bromide) dimeric surfactants successively exhibit the character of phase transfer catalysts through environmentally friendly procedures under mild conditions. The most significant feature of this work is that dimeric surfactants have been determined to act as phase transfer agents.     

Investigation of Wear and Corrosion Behaviour of AISI 316 L Stainless Steel Coated By ESD Surface Modification

Protection of Metals and Physical Chemistry of Surfaces - AISI 316 L austenitic stainless steel is widely used in various sectors of the industry (chemical, petro-chemical industry, paper industry,...     

Immobilization Horseradish Peroxidase onto UiO-66-NH2 for Biodegradation of Organic Dyes

Enzymes are extensively used as catalyst in several fields of production such as chemistry, and pharmaceuticals owing to their selectivity, efficiency and environmentally friendliness. However, their applications are often hindered due to their insufficient stability and difficulties in re-use. As a member of porous crystalline materials, metal organic frameworks are a promising enzyme carrier due to their multi-functional pore surfaces and robustness in variety of harsh conditions. In this study, the horseradish peroxidase (HRP) enzyme was immobilized onto UiO-66-NH₂ (Universitetet i Oslo) by a facile incubation method at the room temperature to improve the stability and reusability of enzyme. The prepared HRP@UiO-66-NH₂ bio-composite was characterized by using FT-IR, XRD and SEM. The crystal structure of MOF was well-preserved after enzyme immobilization. A colorimetric assay for enzyme activity after released from UiO-66-NH₂ has been employed based on the catalytic oxidation of phenol coupled with 4-aminoantipyrine. The robustness and activity of immobilized enzyme after released from UiO-66-NH₂ were investigated by biodegradation of methyl orange (MO) and methylene blue (MB) with several parameters such as pH, temperature, the dosage of H₂O₂ and the dye concentration with comparison to its free form. The optimum condition for dye degradation was obtained at basic conditions. The immobilized enzyme maintained its activity at elevated temperature while free enzyme lost its activity at the same conditions, attributed to the armoring effect of UiO-66-NH₂. According to the results of studied various parameters, MO and MB were biodegraded to 60% and 45%, respectively, within 60 min with the optimum conditions at pH 9 and 50 °C at a H₂O₂ dosage of 3%. The superior pH tolerance and stability suggest potential of UiO-66-NH₂ immobilized peroxidase enzyme in industrial applications.

     

Design and implementation of an ultrasonic sensor for rapid monitoring of industrial malolactic fermentation of wines

Ultrasound is an emerging technology that can be applied to monitor food processes. However, ultrasonic techniques are usually limited to research activities within a laboratory environment and they are not extensively used in industrial processes. The aim of this paper is to describe a novel ultrasonic sensor designed to monitor physical–chemical changes that occur in wines stored in industrial tanks. Essentially, the sensor consists of an ultrasonic transducer in contact with a buffer rod, mounted inside a stainless steel tube section. This structure allows the ultrasonic sensor to be directly installed in stainless steel tanks of an industrial plant. The operating principle of this design is based on the measurement of ultrasonic velocity of propagation. To test its proper operation, the sensor has been used to measure changes of concentration in aqueous samples and to monitor the progress of a malolactic fermentation of red wines in various commercial wineries. Results show the feasibility of using this sensor for monitoring malolactic fermentations in red wines placed in industrial tanks.