Prototype of highly efficient liquid electrode pulsating corona plasma reactor for degradation of organics in water

Prototype of atmospheric pressure non-thermal corona plasma reactor, developed for degradation of organics in water, operates at significantly higher frequency than other reactors for that purpose, and without sparks. Its construction provides the umbrella shaped, sustained pulsating corona discharge, with defined discharge oscillations on a given pulse frequency above the water surface. Dye degradation rate decreases with the decrease of discharge current density. Plasmaformed H_2O_2 is consumed in dye degradation. The energy yield of dye degradation is 2.45 g k Wh~(-1) for 50 ppm solution, which is higher than in other publications for comparable experimental conditions.     

The influence of textual and verbal word-of-mouth on website usability and visual appeal

The Journal of Supercomputing - Word-of-Mouth (WOM) may impact the perception and experience of website usability and visual appeal. This study aimed to highlight the effects of WOM, implemented...     

Encapsulation for preservation of functionality and targeted delivery of bioactive food components

There has been a tremendous increase in the number of food products containing bioactive components with a health promoting or disease preventing effect. Bioactive food components can be divided into bioactive molecules and bioactive living cells (probiotics). Both bioactive molecules and bioactive living cells may benefit from encapsulation since many report low survival of bioactivity due to adverse effects of (i) processing and storage in the products that serve as vehicles and due to (ii) deleterious circumstances during transport through the gastrointestinal tract. For probiotics, it may even be mandatory to apply protection by encapsulation as the survival of probiotics in traditional products such as in dairy foods and powdered formulas is low. Encapsulation promotes not only viability but more importantly also protects the functionality, and may facilitate targeted release in specific parts of the gut. Different encapsulation approaches qualify for protection of bioactive food components. The most commonly applied technologies are emulsification, coacervation, spray drying, spray cooling, freeze drying, fluid bed coating and extrusion technologies, but also more expensive techniques such as liposome encapsulation, and cyclodextrin encapsulation are used. When targeted release is desired in combination with adequate protection in the product, it is essential to realize which processes in the human gut can be applied to facilitate targeted release. The majority of systems that have been used in the past were either sensitive to mechanical stress, pH, or transport time variations in the gut. More recent systems take advantages of the different enzyme concentrations associated with variations in the composition of the microbiota in different parts of the gut. The latter system should receive more attention in the food industry as it allows for precise release of bioactive food components. The principle of targeted release by enzymatic activity of the microbiota is compatible with many carbohydrates that are generally regarded as safe (GRAS).     

In vitro and in vivo antifungal properties of cysteine proteinase inhibitor from green kiwifruit

BACKGROUND: Higher plants possess several mechanisms of defense against plant pathogens. Proteins actively synthesized in response to those stresses are called defense‐related proteins which, among others, include certain protease inhibitors. It is of particular relevance to investigate plant natural defense mechanisms for pathogen control which include cystatins—specific inhibitors of cysteine proteases. RESULTS: In this study, a cysteine proteinase inhibitor (CPI), 11 kDa in size, was purified from green kiwifruit to homogeneity. Immuno‐tissue print results indicated that CPI is most abundant in the outer layer of pericarp, near the peel, and the inner most part of the pulp—sites where it could act as a natural barrier against pathogens entering the fruit. The purified protein (15 µmol L^?1) showed antifungal activity against two phytopathogenic fungi (Alternaria radicina and Botrytis cinerea) by inhibiting fungal spore germination. In vivo, CPI (10 µmol L^?1) was able to prevent artificial infection of apple and carrot with spore suspension of B. cinerea and A. radicina, respectively. It also exerted activity on both intracellular and fermentation fluid proteinases. CONCLUSION: Identification and characterization of plant defense molecules is the first step towards creation of improved methods for pathogen control based on naturally occurring molecules. Copyright © 2012 Society of Chemical Industry     

Immobilization of laccase from Myceliophthora thermophila on functionalized silica nanoparticles: Optimization and application in lindane degradation

This work is focused on immobilization of laccase from Myceliophthora thermophila expressed in Aspergillus oryzae(Novozym 51003? laccase) on amino modified fumed nano-silica(AFNS) and the possible use in bioremediation. Hereby, for the first time, factors affecting the immobilization of Novozym 51003? laccase on AFNS were investigated for defining the immobilization mechanism and optimizing the utilization of AFNS as support for laccase immobilization. The highest specific activity(13.1 IU·mg~(-1) proteins) was achieved at offered 160 mg per g of AFNS and for the same offered protein concentration the highest activity immobilization yield, reaching68.3% after the equilibrium time, at optimum pH 5.0, was obtained. Laccase immobilization occurs by adsorption as monolayer enzyme binding in 40 min, following pseudo-first-order kinetics. The possible use of obtained immobilized preparation was investigated in degradation of pesticide lindane. Within 24 h, lindane concentration was reduced to 56.8% of initial concentration and after seven repeated reuses it retained 70% of the original activity.     

High-performance charge storage by N-containing nanostructured carbon derived from polyaniline

Nitrogen-containing nanostructured carbon materials, C-nanoPANI, C-nanoPANI-DNSA and C-nanoPANI-SSA, were prepared by the carbonization of nanostructured polyaniline (PANI) doped with sulfuric acid, 3,5-dinitrosalicylic acid (DNSA), and 5-sulfosalicylic acid (SSA), respectively. The charge storage ability of these materials was investigated in alkaline solution. It was found that the specific capacitance increased in the order: C-nanoPANI-DNSA < C-nanoPANI < C-nanoPANI-SSA. The highest capacitance, amounting to 410 F g^?1 at a scan rate of 5 mV s^?1, was found for C-nanoPANI-SSA. At a large rate of 10 A g^?1, its capacitance displayed a stable value close to 200 F g^?1. To explain the observed differences in charge storage properties, the materials were characterized by different techniques able to ascertain their morphology, elemental composition, nitrogen surface concentration, chemical state of nitrogen, pore structure and electrical conductivity. All materials were essentially microporous with relatively small fraction of mesopores and displayed conductivities in the range 0.32–0.83 S cm^?1. The best charge-storage performance of C-nanoPANI-SSA was attributed to its highest surface fraction of nitrogen, the highest surface content of pyridinic nitrogen groups, and the highest electrical conductivity, as well as to its well-balanced micro- and mesoporosity and highest content of mesopores.     

Nonlinear frequency response method for estimation of single solute adsorption isotherms. Part II

The aim of this paper is to investigate the possibility of applying a nonlinear frequency response (FR) method described by Ili? et al. [2007b. Nonlinear frequency response method for estimation of single solute adsorption isotherms. Part I. Theoretical basis and simulations, this volume, doi:10.1016/j.ces.2007.05.004] to determine single solute adsorption isotherms. The method is based on the analysis of the nonlinear FR of a chromatographic column to a periodical change of the inlet concentration around several steady-state concentrations. The first, second and third local derivatives of single solute isotherms are estimated from the low-frequency asymptotic behaviour of the corresponding FR functions. The adsorption of 4-tert-butylphenol and ethyl benzoate as single solutes is studied on octadecyl silica (C₁₈) from methanol-water mixture (60:40). Experiments are performed using a standard gradient HPLC unit capable to realize inlet concentration changes in a nearly sine waveform. Small injections of compounds into the not preloaded column, as well as conventional frontal analysis experiments are performed for rough estimation of the adsorption isotherm coefficients and comparison with the results obtained using the nonlinear FR method.     

Voting as the optimal static pessimistic scheme for managingreplicated data

This paper investigates the problem of finding an optimal static pessimistic replica control scheme. It has been widely accepted that coteries (proposed by Garcia-Molina and Barbara) provide the most general framework for such schemes. We demonstrate that voting schemes, a very small subset of static pessimistic schemes, are optimal for fully connected networks with negligible link failure rates, as well as for Ethernet systems. We also show that voting is not optimal for somewhat more general systems. We propose a modification of the algorithm of Z. Tong and R.Y. Kain (1988) for computing optimal voting in operation independent case, so that it runs in linear (rather than exponential) time. Finally, we propose the first efficient algorithm for computing the optimal vote assignment and appropriate thresholds for fully connected networks when relative frequencies of read and write operations are known. We also extend this result to Ethernet systems