bluuebunny/crossref_metadata_2025_split huggingface dataset:
Production and extractive biocatalysis of ethanol using microencapsulated yeast cells and lipase system
Authors: Oliveira A. C. , Cabral J. M. S. 
Published: July 2010

AbstractAn extractive biocatalytic process for in situ ethanol recovery from fermentation broths of high glucose concentration (200 and 400 g dm−3) was developed. In this system, ethanol was recovered by liquid‐liquid extraction and enzymatic reaction. Oleic acid was used as extractant, allowing the esterification of ethanol catalysed by a lipase from Mucor miehei. The distribution coefficient of ethanol between the aqueous and the organic phases was improved tenfold by esterification. The better performance of the extractive fermentations of ethanol was obtained when co‐immobilized Saccharomyces bayanus cells and a lipase from Mucor miehei in microemulsions of phosphatidylcholine were used. These results emphasize the important role of the surfactant in the protection of biocatalysts against organic phase toxicity.
On the solvent‐induced swelling of low‐rank coals
Authors: Jones J. C. , Boother M. , Brown M. 
Published: July 2010

AbstractSwelling of low rank coals due to solvent contact is measured for a suite of such coals from different sources. The method is a simple one: the pouring of solvent on to samples of the coal in glass tubes and measurements of coal height before and after pouring on the solvent. Correlations between swelling and coal properties are discussed, and for one of the coals a ‘swelling spectrum’, displaying swelling as a function of solvent solubility parameter, is presented.
The Effects of Spore Loading on the Growth of Penicillium chrysogenum Immobilised in K‐Carrageenan
Authors: Mussenden Paul J. , Keshavarz Tajalli , Bucke Christopher 
Published: July 2010

AbstractPenicillium chrysogenum spores were immobilised in K‐carrageenan. The effect of the number of viable spores immobilised per bead on the rate of germination and degree of subsequent mycelial growth was investigated. The distribution of active mycelium throughout the bead was determined. At a high spore loading (103−104 viable spores per bead) the biomass concentration was low and the majority of the actively respiring biomass was located at the bead periphery. Reducing the spore loading (to 50 viable spores per bead) resulted in a fourfold increase in immobilised biomass concentration. At very low spore loadings (5 and 10 viable spores per bead) the concentration of biomass decreased, but mass transfer throughout the bead improved and the uniformity of active immobilised biomass increased. The spore loading also affected the morphology of the growing hyphae and the extent of free cell growth.
Simultaneous removal of SO2, SO3 and H2SO4 mist from the gas after TiO2 calcining
Authors: Tilly Jadwiga , Tomaszewski Zbigniew , Toczkowski Jacek 
Published: July 2010

AbstractAbsorption of SO2 and SO3 in the solutions of waste ferrous sulfate (so‐called ‘green salt’) and in the spent acid after TiO2 hydrolysis, at H2SO4 concentrations ranging from 0–5 to 15 g/m3 (STP), was studied. The rate of SO3 absorption has been found to rise linearly with increasing SO3 concentration in the gas and to be independent on H2SO4 concentration in solution. The SO2 absorption also rises linearly with increasing SO2 content in the gas, but diminishes as H2SO4 concentration increases—an upper limit of 100 g H2SO4/kg H2O is indicated. The initial concentration of the solution must not be higher than 40 g H2SO4/kg H2O.
The uptake of copper from aqueous solution by immobilized fungal biomass
Authors: Zhou Jun L. , Kiff Robert J. 
Published: July 2010

AbstractThe removal of cupric ions from aqueous solution by a biosorption column in which the Rhizopus arrhizus fungal biomass was immobilized in reticulated foam biomass support particles was studied. Solution pH was found to be crucial to copper uptake, with the optimum range being 6·7–7·0. The removal efficiency was usually higher at low influent copper concentration and long residence time. The presence of other cations and anions inhibited copper uptake in the following order: for the cations, Mn2+ ≫ Zn2+ > Cd2+ > Mg2+ > Ca2+; for the anions, EDTA ≫ SO ≫ Cl−. The biosorption process was fully reversible and regenerated columns showed undiminished performance.
Spectrophotometric determination of uranium(VI) in bacterial leach liquors using arsenazo‐III
Authors: Bhatti Tariq M. , Mateen Abdul , Amin M. , Malik Kauser A. , Khalid Ahmad M. 
Published: July 2010

AbstractA highly sensitive and precise spectrophotometric method for the direct determination of uranium(VI) in bacterial leach liquors, obtained by the action of Thiobacillus ferrooxidans and T. thiooxidans, from low‐grade sandstone uranium ores, has been developed, Arsenazo‐III formed an intense pink‐violet complex at pH 2·0 ± 0·1, which showed maximum absorption at 655 nm. This method was found to obey Beer's law up to 6 μg cm−3, giving the values of molar absorptivity (ϵ) and Sandell sensitivity (S) as 4·6 × 104 mol−1 cm−1 and 0·0052 μg cm−2, respectively. Interference due to different metal ions, such as Al, Ca, Co, Cr, Fe, Mn, Mo, Zn and Zr, was successfully masked by diethylenetriaminepenta‐acetic acid without inhibiting the formation of the uranium(VI)‐arsenazo‐III complex. This method was also found suitable for detecting low levels of uranium(VI) in mine waters, acid leach liquors and tailings liquids. The results obtained were found to be in close agreement with the values determined by fluoro‐metric and indirect spectrophotometric methods.
Activated sludge characteristics in relation to stable foam formation
Authors: Khan A. R. , Kocianova E. , Forster C. F. 
Published: July 2010

AbstractThis paper examines the hydrophobicity and the surface charge of a range of foaming and nonfoaming activated sludges, together with an appraisal of the species involved. The results show that the solids in foaming sludges possess a higher hydrophobicity than those in nonfoaming sludges. The data also indicate that there are two distinct hydrophobicity/surface charge trends, depending on whether the sludges are foaming or nonfoaming. Sludges in which Nostocoida limicola was the dominant species did not conform to these patterns. In addition, the stability of the foam formed by these sludges was significantly lower.
The effect of steam and hydrogen in promoting the oxidation of carbon monoxide over a platinum on alumina catalyst
Authors: Muraki Hideaki , Matunaga Shin‐Ichi , Shinjoh Hirofumi , Wainwright Mark S. , Trimm David L. 
Published: July 2010

AbstractSteam‐ and hydrogen‐induced effects on carbon monoxide oxidation at temperatures below 200°C were studied over an alumina‐supported Pt catalyst. These studies were complemented by measurements of rate expressions and IR spectroscopy. CO oxidation activity over alumina‐supported Pt, Pd and Rh catalysts was found to be strongly promoted by the presence of steam and H2 in the feed gas. The promotion effect decreased in the order Pi>Pd> Rh. The water‐gas shift reaction did not occur under these experimental conditions. The steam and H2 enhancement effects are attributed to the weakening of self‐poisoning by CO.
Design considerations for an immobilized cell bioreactor operating in a batch recirculation mode
Authors: Lakhwala Fayaz , Sofer Sam 
Published: July 2010

AbstractImmobilizing microbial cells and enzymes used in biological and biochemical processes is advantageous and has been a subject of intensive study in recent years. Successful implementation of this technology requires complete understanding of physical, chemical and biological parameters which influence the performance of such a system. This paper focuses on a few basic design considerations which are essential to the design and operation of immobilized cell bioreactors. A process using microorganisms entrapped in calcium alginate gel as a biocatalyst is considered. This system is used to biodegrade the organic compound, phenol. A batch reactor operated in a recirculation mode is used, and parameters like concentration of dissolved oxygen, concentration of the organic compound, bead size, biomass loading and the flow rate are studied. The bioreactor can be operated within many operating windows where one of the above parameters may be rate limiting. With the help of conceptual and experimental data, the influence of the above parameters on the reaction rates is discussed.
Effect of Immobilisation on the Production of α‐Amylase by an Industrial Strain of Bacillus amyloliquefaciens
Authors: Argirakos George , Thayanithy Kuganakathasan , John Wase D. A. 
Published: July 2010

AbstractThe effect of immobilisation of an industrial strain of Bacillus amyloliquefaciens in calcium alginate beads on production of α‐amylase was investigated using lactose‐based media in shake flasks and in a 0.3 dm3 glass fermenter. Although the microorganism was a good α‐amylase producer in batch cultures of free cells, it was unable to produce the enzyme for extended periods either in repeated batch cultures, or in continuous cultivation. In each case, parallel tests with cells immobilised in calcium alginate beads gave still further reduced enzyme yields, and the free cells released into the broth from these beads probably contributed substantially to any amylase produced during these extended fermentations. After prolonged use, the core of the alginate beads accumulated hard insoluble material, with viable immobilised cells confined to a surface layer.
Preparation of Aluminum Hydroxide Gels by Precipitation: Effect of Proton Acceptors on Surface Area and Porosity
Authors: Bakoyannakis Demetris N. , Stalidis George A. , Zamboulis Demetris X. 
Published: July 2010

AbstractThis work has been undertaken to study the effect of varying chain length of primary amines on the preparation of aluminum hydroxide gels by precipitation. The aluminum hydroxide gels have been prepared by precipitation from ethanolic solutions of AlCl3.6H2O adding primary amines (propylamine, octylamine, dodecylamine) which acted as proton acceptors during the hydrolysis reaction and made the precipitation possible. The prepared samples were freezedried and activated to temperatures of up to 773 K. This technique produced in general amorphous samples of high specific surface area (up to 570 m2 g%−1). The specific surface area measured by nitrogen adsorption and the pore size distribution determined by mercury porosimetry were differentiated according to the chain length of the amine used. These differences were further enhanced on thermal activation to the aforementioned temperatures.
Induction of Granulation by Sulphonated‐Lignin and Calcium in an Upflow Anaerobic Sludge Bed Reactor
Authors: Guiot Serge R. , Rocheleau Sylvie , Hawari Jalal , Samson RéJean 
Published: July 2010

AbstractThe present study evaluates the capability of sulphonated lignin (S‐lignin) and calcium to promote anaerobic sludge granulation, which is of prime importance in the operation of upflow anaerobic sludge bed (UASB) ‐like reactors. One of two reactors fed with a synthetic sugar waste was stepwise supplemented with a spent liquor rich in S‐lignin from a neutral sulphite semi‐chemical pulping plant to reach an addition rate of 0.17 g S‐lignin per gram volatile suspended solid (VSS) per day. This resulted in biomass pre‐granulation (50–60% of the biomass aggregates had a size > 0.3 mm). No change was observed in the surface properties (hydrophobicity and zeta potential) of the bacterial aggregates. The S‐lignin‐fed sludge aggregated in an ordered and cluster‐like manner and exhibited a more compact ultrastructure than the control sludge. Moreover, the addition of S‐lignin slightly enhanced the metabolic activities of the biomass. Calcium ion addition following the S‐lignin treatment improved the size and the settleability of the aggregates and increased the solid retention time.
The Chemical and Physical Structure of Peat Bitumens
Authors: Leahy James J. , Birkinshaw Colin 
Published: July 2010

AbstractPeat bitumen obtained by solvent extraction of Irish high moor peat was subjected to chemical, structural and rheological characterisation. The bitumen was fractionated on the basis of solubility in n‐heptane, toluene and ethyl acetate into wax, resin and asphaltene; each of these major constituent groups was further separated into sub‐fractions by column chromatography using solvents of increasing polarity. All materials were chemically characterised by C, H, N and O content and infra‐red spectroscopy. Molecular size distribution of the materials was determined by gel permeation chromatography and vapour pressure osmometry. Heats of fusion, measured using the differential scanning calorimeter, indicated that crystalline species were concentrated in the wax fraction. The rheological properties of the bitumen were investigated between 10 and 50°C, and the fractions were examined at 20°C. Following analysis as yield pseudoplastic fluids, flow behaviour was described in terms of yield stress, flow and consistency indices. The measured flow parameters were examined in the light of the structural implications of the calorimetry and the results of the chemical analysis. Carboxylic acids and esters which are found principally in the wax fraction are considered to be the dominating rheological influence in the bitumen, affecting physical behaviour through their ability to crystallise at low temperature and thus mechanically hinder flow, and through secondary bonding increasing viscosity in the liquid phase.
The Anaerobic Biodegradation of a Bagasse‐Based Paper‐Mill Waste in Fixed‐Film Reactor
Authors: Prasad Duggirala Yogendra 
Published: July 2010

AbstractThe high concentration of biodegradable constituents in waste‐water derived from bagasse‐based paper mills warrants the consideration of an anaerobic biotechnology process to recover biogas and reduce the pollution load. An anaerobic down‐flow fixed‐film bark reactor process was studied to treat waste‐water generated from bagasse‐based paper mills. At the anaerobic stage, 90–95% of the total chemical oxygen demand (COD) was removed at loading rates of 3–18 kg COD m%−3 day%−1 without supplying any nutrients or trace elements. A yield coefficient of 0.156 g cells (g COD) %−1 was calculated at a high COD loading rate of 18 kg COD m%−3 day%−1. With the anaerobic treatment process it is estimated that 1 m3 of bagasse waste‐water with a COD content of 13000 mg dm%−3 can produce about 3.5 m3 of methane. Intermittent checks on the system alkalinity revealed that feed neutralization to maintain alkalinity would be necessary with sodium bicarbonate at approximately 2500 mg dm%−3 for achieving steady‐state high treatment efficiency.
Silver Electrodeposition from Photographic Processing Solutions
Authors: Grau Javier M. , Bisang JoséM. 
Published: July 2010

AbstractThis paper describes the parameters that are important in the industrial practice of silver removal from photographic fixers. The experiments were performed under potentiostatic control using synthetic solutions. The current efficiency was analysed as a function of the cathodic potential taking into account the deposit quality. A cathodic potential of −0.5 V against a saturated calomel electrode is recommended. The conditions to prevent the darkening of the electrodeposit were investigated. The determination of silver concentration in the solution was made by direct potentiometry. The results obtained with synthetic fixers were corroborated by making the silver deposition from commercial fixers in an electrochemical reactor with rotating cylinder electrode intercalated in an electrolytic flow circuit in order to simulate practical conditions.
Stability of Lactobacillus bulgaricus immobilized in K‐carrageenan gels
Authors: Büyükgüngör Hanife 
Published: July 2010

AbstractThe future application of immobilized microorganism techniques will depend on the development of systems which are technologically applicable on an industrial scale. These techniques must permit high microbial concentrations and must allow mass transfer to take place with low diffusional limitations. In addition, the mechanical separation of the immobilized microorganisms must be achieved economically, K‐carrageenan was used as an ionotropic gel carrier for the immobilization of Lactobacillus bulgaricus (ATCC 11842), and the effects of gel stability on productivity and the rate of product formation were investigated. K‐carrageenan gels had higher mechanical and chemical stability than alginate gels. The storage stability of microorganisms immobilized in K‐carrageenan was good enough to retain biocatalytic activity during prolonged storage at 4°C.
Use of Aspergillus niger to improve filtration of olive mill waste‐waters
Authors: Hamdi Moktar , Ellouz Radhouane 
Published: July 2010

AbstractThe high levels of dry matter (70–200 g dm−3) and total suspended solids (TSS) of up to 50 g dm−3 which are present in olive mill waste‐waters (OMW) render these very difficult to filter. During filtration of the OMW viscous solution, a cake is formed by the TSS which decreases the kinetics of the process. Addition of pellets of the fungus Aspergillus niger modifies the cake porosity and thus improves the OMW filtration process. Improvement to the filtration is directly related to the quantity of A, niger added and is attributable to the fermentation of OMW by A. niger since the TSS are trapped by the fungal pellets. The degradation of pectin by A. niger pectinases may also be partly responsible for the increase in the filtration capacity.
Characterization and use of a penicillin acylase biocatalyst
Authors: Ospina S. Sonia , Lopez‐Munguia Agustín , Gonzalez Rosa Luz , Quintero Rodolfo 
Published: July 2010

AbstractA complete characterization of a penicillin acylase biocatalyst is presented, including the determination of physicochemical and kinetic parameters. Stability studies are detailed in terms of both storage temperature and pH as well as operational stability after 150 batch reactions of two hours duration each. An Arrhenius‐type model was used to simulate the effect of pH on biocatalyst stability. A kinetic model is proposed to describe batch and continuous stirred tank reactors and to predict the long‐term behavior of the process.
Decoloration of indene—coumarone resins by catalytic hydrogenation
Authors: Coca José , Rosal Roberto , Diez Fernando V. , Sastre Herminio 
Published: July 2010

AbstractThe catalytic hydrogenation of indene—coumarone resins, a coal‐derived polymer, has been carried out using commercially available catalysts. Hydrogenation of the resins causes the saturation of double bonds and leads to decoloration of the product, increasing its market value. A nickel‐on‐kieselguhr catalyst (Süd‐Chemie G‐49‐BRS) seems to be the most active and gives the highest degree of decoloration. However the decolorated resins tend to recover spontaneously their former colour, the process being only slightly prevented by the addition of stabilizers.
Experimental simulation of the infinite slab in thermal ignition
Authors: Jones J. C. , Gray B. F. , Rahmati H. 
Published: July 2010

AbstractA novel piece of apparatus is described which simulates rigorously the ‘infinite slab’ in traditional thermal ignition theory. The apparatus was applied to shavings of a particular type of wood, and the results are shown to be consistent with those from more conventional experiments using basket heating.
Long chain phenols—part 30: A rate study of the mannich reaction of phenols (with particular reference to 3‐pentadecylphenol)
Authors: Short Eric L. , Tychopoulos Vasiliki , Tyman John H. P. 
Published: July 2010

AbstractThe rate of the Mannich reaction between 3‐pentadecylphenol, di‐n‐propylamine and 40% aqueous formaldehyde in aqueous ethanol under basic conditions has been studied by an HPLC analytical technique following preliminary experiments with dimethylamine, diethylamine and morpholine. The effect of excess amine and excess formaldehyde, different temperatures and the influence of pH were investigated. Kinetic expressions involving the concentrations of the phenol, amine and formaldehyde have been obtained on the assumption of the participation of either (a) the aminal (methylene‐bis‐amine) or (b) the aminol (methylolamine) for five cases covering the various molar proportions of reactant used experimentally. Initially, to test the equations for reactions effected at constant water concentration, theoretical values of t (time) were obtained as the initial concentration (a) of the phenol was varied by increments by a/20 using trial values for the composite rate constant. In this manner the best visual fit between the experimental points and the theoretical curves was obtained. The rate constant corresponding to such a curve was subsequently refined using a least squares procedure to yield the value which minimised the sum of the residuals between the experimental and theoretical values. In all cases the sum of the residuals was smaller when the kinetic expression derived assuming participation of the aminal was employed. The latter assumption also led to a smaller dispersion in the values obtained for the composite reaction constant from the different experiments.
Multienzyme membranes for biosensors
Authors: Krysteva Milka A. , Yotova Lyubov K. 
Published: July 2010

AbstractArtificial multienzyme complexes were prepared in which enzymes were covalently bound to polysaccharide structures activated with urea and formaldehyde. Double enzyme complexes of glucose oxidase and catalase, a glucose oxidase and invertase, were prepared by immobilization on to cellulose fabric. Also, catalase was covalently bound to soluble dextran. The resulting multienzyme systems were highly active and stable, making them suitable for use in measuring the concentrations of glucose and saccharose in solutions. The measurements were performed using an amperometric oxygen electrode and multienzyme membranes containing glucose oxidase and catalase for the first substrate, as well as glucose oxidase bound to cheese‐cloth and a ‘liquid’ membrane of dextran‐bound catalase. To determine the concentration of saccharose, a multienzyme membrane with bound glucose oxidase and invertase was used in combination with a ‘liquid’ dextran—catalase. The enzyme electrodes exhibited a measuring range of 0.1–5 mol dm−3 and a response time of 2–3 min.The electrodes may be used for measuring saccharose and glucose concentrations both in fermentation broths and food products.
Hydrophile lipophile balance of hydroxyoximes in McGowan scale and their partition and extraction properties
Authors: Szymanowski Jan , Voelkel Adam 
Published: July 2010

AbstractHydroxyoxime hydrophobicity was characterized by hydrophile lipophile balance in McGowan scale, and the relationship's log partition coefficient vs HLBGa and extraction rate vs HLBGa were discussed. The effect of the alkyl length and structure upon hydroxyoxime hydrophile lipophile balance and partition coefficients can be qualitatively considered using the effective length of the alkyl. The partition data for homologous series can be predicted from HLBGa. Relationships between extraction rate and HLBGa do not support the traditional view of the extraction mechanism. It supports the idea of the mechanism change from the bulk aqueous to the interfacial mechanism with the increase in hydroxyoxime hydrophobicity.