Purification of soybean oil with phospholipase Al

An enzymatic degumming step in the production of edible soybean oil is carried out. The phosphatides are present in free hydratable form (HP) or in nonhydratable form (NHP). The main characteristic of the discovery is the use of phospholipid A1 (Lecithin Ultra) enzyme, which catalyzes reactions at specific temperatures. The mechanism includes the conversion of nonhydratable phospholipids into water-soluble lysophospholipids, which are then removed by centrifuge, yielding degumming oil low in phosphorus. The effects of important determining factors affecting oil degumming such as enzyme dosage, temperature and pH are investigated.     

Demonstration of a 1/4-cycle phase shift in the radiation-induced oscillatory magnetoresistance in GaAs/AlGaAs devices

We examine the phase and the period of the radiation-induced oscillatory magnetoresistance in GaAs/AlGaAs devices utilizing in situ magnetic field calibration by electron spin resonance of diphenyl-picryl-hydrazal. The results confirm a f-independent 1/4-cycle phase shift with respect to the hf=j variant Planck's over 2pi omega(c) condition for j>/=1, and they also suggest a small ( approximately 2%) reduction in the effective mass ratio, m(*)/m, with respect to the standard value for GaAs/AlGaAs devices.     

Shape invariance for the bent brane with two scalar fields

In this paper, we study the braneworld scenarios in the presence of two real scalar fields coupled by gravity. The first-order formalism for the bent brane (for both de Sitter and anti-de Sitter geometry), leads us to discuss the shape invariance method in the bent brane systems. So, by using the fluctuations of metric and fields we obtain the Schrödinger equation. Then we factorize the corresponding Hamiltonian in terms of multiplication of the first-order differential operators. These first-order operators lead us to obtain the energy spectrum with the help of shape invariance method.     

Raising and Lowering of Generalized Hulthén Potential from Supersymmetry Approaches

We obtain the exact bound states of the generalized of Hulthén potential with negative energy levels using an analytic approach. In order to obtain bound states, we use the associated Jacobi differential equation. Using the supersymmetry approach to quantum mechanics, we show that these bound states, via four pairs of first order differential operators, represent four types of ladder equations. Two types of these supersymmetric structures suggest derivation of algebric solutions for the bound states using two different approaches. PACS 21.60.Cs; 21.60.Fw; 21.60.-n; 03.65.Fd; 03.65.Ge; 03.65.-w     

Polymeric membrane coated graphite cesium selective electrode based on 4′,4″(5′) di–tert-butyl di-benzo-18-crown-6

A new PVC membrane coated graphite electrode for cesium ion based on 4′,4″(5′)di–tert-butyl di-benzo-18-crown-6 (DTBDB18C6) as ionophore was prepared. The electrode shows a near Nernstian response of 57.0 ± 1.8 mV decade^?1 over a wide activity range of 6.0 × 10^?6–1.0 × 10^?1 mol L^?1 with a limit of detection 4.0 × 10^?6 mol L^?1. The proposed electrode is suitable for use in aqueous solution in the pH range of 3.0–9.5. It has a fast response time of 10 s and can be used for at least 1 month without any considerable divergence in potential. The selectivity coefficients for Cs⁺ ion with respect to ammonium, alkali, alkaline earth and some selected transition metal ions were determined and showed a superior selectivity over Li⁺, Na⁺ and alkaline earth metal ions. The new electrode was applied for determination of Cs⁺ in spiked tap water. The electrode was also used as indicator electrode in potentiometric titration of Cs⁺ with sodium tetraphenyl borate.     

Kinetics of decomposition of hydrogen peroxide on Fe(III)?Al(III) hydroxide-oxide systems

The kinetics of decomposition of hydrogen peroxide have been studied on mixed Fe(III)–Al(III) hydroxide and oxide catalysts. While iron hydroxide possesses considerable catalytic activity, aluminium hydroxide has very little activity. The rate of decomposition on mixed hydroxides increases with increasing concentration of aluminium hydroxide up to about 1.5 mol% and decreases thereafter. The mixed oxides possess negligible activity compared to the corresponding hydroxides. The energy of activation, as calculated from the Arrhenius equation, is 10.1 kcal/mol for sample S4, containing 1.52 mol% of alumina. The rate of decomposition of S4 increases with increasing pH up to 6.8 and decreases thereafter. The rate is first order in all these cases. A suitable mechanism is suggested.

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Fe(III)–Al(III). , . , 1,5 , . . , , 10,1 / S4, 1,52 . S4 pH 6,8, . . .

     

Hydroxypropyl chitosan bearing beta-cyclodextrin cavities: synthesis and slow release of its inclusion complex with a model hydrophobic drug

Hydroxypropyl chitosan-graft-carboxymethyl beta-cyclodextrin (HPCH-g-CM beta-CD) was synthesized by grafting CM beta-CD onto HPCH using water soluble 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) as the condensing agent. Due to the presence of hydrophobic beta-CD rings onto the HPCH backbone, this polymer can be used as a matrix for controlled drug release. The adsorption of a hydrophobic model drug, ketoprofen, by HPCH-g-CM beta-CD microparticles (using tripolyphosphate as an ionic crosslinking agent) fitted well in the Langmuir isotherm equation. The drug dissolution profile showed that HPCH-g-CM beta-CD microparticles provided a slower release of the entrapped ketoprofen than chitosan, and the release behavior was influenced by the pH value of the medium. These results suggest that beta-CD grafted with chitosan derivatives may become a potential biodegradable delivery system to control the release of hydrophobic drugs with pH-responsive capability.     

A study on the influence of dysprosium cation substitution on the structural, morphological, and electrochemical properties of lithium manganese oxide

The synthesis of series of dysprosium-doped lithium manganese oxide in the general formula LiDy _x Mn_2?x O4 (x?=?0.0, 0.05, 0.1, 0.15, and 0.2) using double stage coprecipitation method followed by microwave heat treatment is reported. The characterization results of X-ray diffraction and infrared spectroscopy have illustrated the cubic structure for all the compounds. The lattice parameter has been observed to decrease with dysprosium doping. The influence of doping in elastic property of the samples has been studied with infrared spectroscopy. The grain size of the LiDy_0.05Mn_1.95O₄ has been observed to be less than 1???m. The Image J software has been used to further analyze the micrographs. The initial capacity of the samples are observed to decrease with Dy³⁺ doping, but the capacity retention after 50 cycles for Dy 0.05, 0.1, 0.15, and 0.2 samples are reported as 95.4%, 93.2%, 91.3%, and 87.7%, respectively. The electrochemical impedance spectra has been performed to analyze the effectiveness of Dy³⁺ ion doping and the act of Dy doping has been observed to reduce the charge transfer resistance and increase the Li ion diffusion coefficient.