bluuebunny/crossref_metadata_2025 huggingface dataset:
New dyestuffs for synthetic fibres, benzimidazo‐thioxantheno‐isoquinolin‐ones
Authors: Grayshan P. H. , Mak K. H. R. , Peters Arnold T.
Published: July 2010

Condensation of 3‐ and 4‐bromo‐ or nitro‐7H‐benzimidazo[2,1‐α]benz[d,e]isoquinolin‐7‐ones with 2‐aminobenzenethiol, followed by Pschorr cyclisation of the resultant product, afforded the isomer mixture of the new heterocycles benzimidazo[1,2‐b]thioxantheno[2,1,9‐d,e,f,]isoquinolin‐7‐one and benzimidazo[2,1‐a]thioxantheno[2,1,9‐d,e,f,]isoquinolin‐8‐one. Separation of these isomers and their characterisation by unambiguous synthesis is reported. Small amounts of analogous 5‐membered sulphur heterocycles were also formed by cyclisation in the β‐position of the naphthalene ring. These new heterocycles dye synthetic fibres in fluorescent orange and yellow shades, showing excellent fastness to light and sublimation. Principal mass spectra features of the compounds are given.
The SCI/IUPAC/NPL project on surface area standards
Authors: Everett Douglas H. , Parfitt Geoffrey D. , Sing Kenneth S. W. , Wilson Raymond
Published: July 2010

Values of the nitrogen BET specific surface areas calculated from data supplied by many laboratories on four currently available surface area standards are presented and compared. Analytical data, representative adsorption isotherms and typical BET plots are given. Various factors affecting the accuracy of nitrogen BET surface area measurements are summarised.
Alkylation of the aromatic nucleus
Authors: Badr M. Zarif A. , Abdel‐Rahman A. E.
Published: July 2010

The proportion of α‐ and β‐alkyl naphthalenes has been determined in the products of the thermal decomposition of sulphonic acid esters of ethyl, isopropyl and sec‐butyl alcohols in naphthalene as aromatic solvent, The isomer ratios from alkylation by sulphonic acid esters are compared with that produced in alkylations by the alcohols and sulphuric acid or phosphoric acid as condensing agents. Aluminium chloride, when used as a catalyst affected the process of dealkylation—alkylation to a great extent during alkylation reaction resulting in a large difference in isomer ratio as observed.
A general model for the packed bed encapsulated enzyme reactor
Authors: Ramachandran P. A.
Published: July 2010

A model has been developed for the performance of a packed bed encapsulated enzyme reactor which includes all the resistances controlling the rate of reaction plus the effect of axial dispersion of the bulk liquid. The method of solution to the problem is based on the application of the orthogonal collocation method to both the enzyme capsule and the bulk liquid, thereby reducing the problem into one of solving a number of simultaneous first order ordinary differential equations.
Thiamine accumulation in yeast
Authors: Stieglitz Barry , Levy Rachel , Mateles Richard I.
Published: July 2010

A comparison was made of the ability of several commercially significant yeast species to accumulate the vitamin thiamine. Saccharomyces cerevisiae accumulated two to four times as much thiamine as Candida tropicalis, Kluyveromyces fragilis, or Kluyveromyces lactis. Thiamine accumulation by yeasts in shaker flasks was two to three times greater than in a small fermentor.
Ultraviolet absorption spectra: Some substituted coumarins
Authors: Masrani K. V. , Rama H. S. , Bafna S. L.
Published: July 2010

The u.v. absorption spectra of forty‐one substituted coumarins have been studied in methanol and aqueous methanol over a pH range. The effect of the nature and position of the substituent in the coumarin nucleus is discussed.
Ion‐exchange properties and possible applications of weathered Antrim basalts
Authors: Alexander George C. , Heal Henry G.
Published: July 2010

The composition and ion‐exchange properties of weathered and hydrothermally altered Antrim basalts have been examined. Lightly weathered olivine basalt contains large quantities of smectites with good cation‐exchange capacity, adequate rates of exchange for practical applications, and useful selectivity. Much of the available basalt is suitable for direct use in ion‐exchange beds after crushing and screening. Laboratory tests of possible applications are described; the most promising are the removal of caesium‐137 from nuclear waste waters and of ammonia from treated sewage effluents.
Petroleum sulphonates: Production and evalution as corrosion inhibitors
Authors: Abdelkader M. Hilal , Gouda Venice K.
Published: July 2010

Sodium and calcium petroleum sulphonates have been prepared by sulphuric acid treatment of the Egyptian Morgan 350–450 °C petroleum fraction. Extraction and purification of the sulphonates from the sulphonated oil and the residual acid sludge is described. Corrosion studies revealed that the sodium petroleum sulphonates are more effective as corrosion inhibitors than the calcium salts in a neutral as well as in an acid medium. A maximum inhibition efficiency of about 75% was obtained by the sodium salt in an acid and a neutral medium, while the relevant value obtained by the calcium salt is 60 and 23% in an acid and a neutral medium respectively. It has been also found that both salts accelerated corrosion when used at relatively high concentration in a neutral medium. Results are discussed according to the current views of corrosion inhibition.
A kinetic study on the reduction of manganese III in presence of citric acid
Authors: Guindy Nabila M. , Basily E. K. , Milad N. E.
Published: July 2010

The rate of reduction of manganese III stabilised by citric acid under variable conditions of Mn(III) concentration, ionic strength, pH and temperature in buffered media was found to obey a second order rate equation, first order with respect to Mn(III) autocatalysed by Mn(II). The reduction was found to proceed to an equilibrium value. The observed rate constants were found to follow a linear relationship with hydrogen ion concentration. Interpretation of results is based on the assumption that there are two reducible species in equilibrium; the aquocomplex and its hydrolysed form. A reaction mechanism is proposed to account for the experimental results. The overall energy (ΔE) and entropy (ΔS) of activation are compared with those for the reduction of Mn(III) in presence of other organic substrates.
The theory of fed batch culture with reference to the penicillin fermentation
Authors: Pirt S. John
Published: July 2010

A batch culture of microbes fed continuously with culture medium is described as a “fed batch culture”. When a portion of a “fed batch culture” is withdrawn at intervals the system is described as a “repeated fed batch culture”.

A fed batch culture may reach a “quasi‐steady state” in which the specific growth rate (μh−1) virtually = the dilution rate, that is, the ratio of medium flow rate to culture volume. In a quasi‐steady state the specific growth rate gradually decreases. A unique feature of a fed batch culture is that it allows continuous reproduction of the transient conditions between two specific growth rates, which can be chosen at will. Fed batch culture may be used to determine the relation between specific growth rate and the growth‐limiting substrate concentration and to determine the maintenance energy. Simple relations are derived to enable the concentrations of products to be predicted.

The effects of different cycle times in repeated fed batch culture applied to the pencillin fermentation are discussed.

Repeated fed batch culture should find a major application in the production of secondary metabolites which often are synthesised at maximum rates only transiently.
Prediction of effective thermal conductivity of two‐phase porous media by nomogram
Authors: Chaurasia P. B. Lal , Chaudhary D. R. , Bhandari R. C.
Published: July 2010

A nomogram for the prediction of the effective thermal conductivity of two phase porous media is presented which is constructed according to the Chaudhary and Bhandari equation based upon the geometric mean of maximum and minimum thermal conductivities. A chart estimating the effective thermal conductivity values between probable limits and a nomogram determining porosity values are also included.
Derivation of a generalised monod equation and its application
Authors: Konak A. R.
Published: July 2010

A generalised growth rate equation is derived which relates the specific growth rate of bacteria to the concentration of a limiting nutrient in a bacterial culture. Monod's simple hyperbolic and Teissier's exponential equations are shown to be two special cases of this general equation. It is also revealed that the so‐called Michaelis‐Menten constant in Monod's simple equation is inversely proportional to the maximum specific growth rate.
The basic lead nitrates I. Compounds formed by the reaction of orthorhombic lead monoxide with cold aqueous lead nitrate
Authors: Michell E. W. John
Published: July 2010

Solid products of the reaction between orthorhombic lead monoxide and cold aqueous lead nitrate solutions in the range of molar proportions 1:3 to 3:1 PbO: Pb(NO3)2 have been studied by X‐ray powder diffraction (X.R.P.D.). Three distinct crystalline phases were recognised.

Reasonably pure samples of monobasic lead nitrate dihydrate [dilead (II) monoxide dinitrate dihydrate], PbO.Pb(NO3)2.2H2O, were obtained at temperatures below 20 °C when the reactants were in the range of molar proportions 1:3 to 1:1 PbO: Pb(NO3)2. This compound seems to be stable below 20 °C, but it partially dehydrates at higher temperatures. It does not seem to have been reported elsewhere. Monobasic lead nitrate monohydrate [dilead (II) monoxide dinitrate monohydrate], PbO.Pb(NO3)2.H2O, was formed in isolation at temperatures between 25 and 30 °C when the reactants were in the range of molar proportions 1:3 to 1:1 PbO: Pb(NO3)2. This compound is stable at room temperatures, and is identical to phases which have been reported by other authors. Mixtures of these two substances were obtained at temperatures between 20 and 25 °C. Tribasic lead nitrate trihydrate [tetra lead (II) trioxide dinitrate trihydrate], 3PbO.Pb(NO3)2.3H2O, was formed in isolation at all temperatures in the range 15 to 30 °C when the reactants were in the molar proportion 3:1 PbO: Pb(NO3)2. This compound seems to be stable at room temperatures and has been reported elsewhere. When the reactants were in the molar proportion 2:1 PbO: Pb(NO3)2, mixtures of tribasic lead nitrate trihydrate with one or other (or both, depending on the temperature) of the monobasic lead nitrate hydrates were obtained.

X.R.P.D. data are given for these three compounds, and a critical assessment is made of all the results in the cases of the two compounds for which published data already exists. Also, it is suggested that compounds of stoichiometries intermediate between that of a monobasic lead nitrate hydrate and that of a tribasic lead nitrate hydrate (and which have been described in the literature) can be only metastable in contact with water. The nomenclature used in this paper follows common industrial practise in naming basic lead compounds. However, scientific names are also given in parentheses when necessary.
The effect of amino acids and amino acid analogues on growth of an obligate methanotroph, Methylosinus trichosporium OB3b
Authors: Warner Philip J. , Drozd Jan W. , Higgins I. John
Published: July 2010

The sensitivity of the obligate methanotroph, Methylosinus trichosporium OB3b to a number of amino acid analogues and amino acids has been examined. Sulphaguanidine (5 μg ml−1) norleucine (100 μg ml−1) m‐fluorophenylalanine (50 μg ml−1), p‐fluorophenylalanine (50 μg ml−1) and S2‐aminoethyl‐C‐cysteine (1000 μg ml−1) inhibited growth. Proline, threonine, methionine and lysine (2–4 μg ml−1) also inhibited growth, but arginine and leucine at similar concentrations had no effect. Attempts were made to isolate amino acid analogue resistant mutants, which would be expected to overproduce amino acids. Two approaches were made, selection of spontaneous and induced mutants in plate culture, and selection of a spontaneous mutant during growth in continuous culture under selective conditions, but no mutants were obtained. Possible reasons for failure to obtain such mutants are discussed.
The extraction of citric acid from fermentation broth using a solution of a tertiary amine
Authors: Wennersten Ronald
Published: July 2010

Tertiary amines are effective extractants for citric acid. The effect of diluents on the extraction is very important since it affects the distribution of citric acid, the selectivity and the phase separation properties. The distribution coefficient for citric acid is strongly temperature dependent. This makes it possible to strip the acid into water at a higher temperature. Alamine 336 dissolved in a nonpolar diluent is a suitable solvent. Pilot plant runs show that the process is technically feasible.
Saccharification of bagasse using a counter‐current plug‐flow reactor
Authors: Fox David , Dunn Noel W. , Gray Peter P. , Marsden Warwick L.
Published: July 2010

A method for the simulation of a 3‐stage counter‐current plug‐flow reactor (PFR) for the enzymic Saccharification of alkali‐treated (a.t.) sugar cane bagasse is described. The PFR gave higher conversion than a conventional stirred‐tank reactor (STR). The STR achieved 44.3% conversion while the PFR achieved 56.4% conversion using 11 % a.t. bagasse after 48 h. The PFR offers potential for more efficient mass transfer and enzyme utilisation, and reduced end product inhibition.
Growth of Thiobacillus ferrooxidans on ferrous iron in chemostat culture: Influence of product and substrate inhibition
Authors: Jones Carol A. , Kelly D. P.
Published: July 2010

Thiobacillus ferrooxidans was grown at pH 1.6 in continuous flow chemostat culture on ferrous sulphate as growth limiting substrate at dilution rates between 0.02–1.33 h−1. Iron oxidation and growth were subject to product inhibition by ferric iron and under some conditions substrate inhibition by ferrous iron. Product inhibition could be predominantly competitive or non‐competitive, and the mode observed depended partly on previous steady state conditions. The inhibition phenomena resulted in unique anomalous washout curves and complex relationships between steady‐state substrate, product and biomass concentrations, for which mathematical models are developed. For the growth states subject to non‐competitive inhibition by Fe3+ at D 0.073–0.99 h−1, the growth yield coefficient corrected for maintenance (YG) was 1.33 g dry wt (g atom Fe2+ oxidized)−1 and the maintenance coefficient (m) was 0.43 g atom Fe2+ oxidized (g dry wt)−1 h−1). For predominantly competitive states (D, 0.05–0.268 h−1) with 2–70 mM Fe3+ in steady states, YG was 0.36–0.38 and m was 0–0.04. A consequence of product inhibition and substrate inhibition was the possibility of more than one steady state product value and yield for a single steady state substate concentration. This was demonstrated experimentally. Substrate saturation coefficient, Ks (giving half maximum specific growth rate) for Fe2+, was 0.7–2.4 mM and maximum specific growth rate (μm) 1.25–1.78 h−1. The results presented reveal unusual and novel properties of T. ferrooxidans relevant to describing its activities in natural environments or in mineral leaching systems.
Study on the acid hydrolysis of Peat: 1. extraction of carbohydrates
Authors: Martin Antonio M. , Bailey Valerie I.
Published: July 2010

Peat and its derived products such as peat extracts or hydrolysates offer a variety of possibilities as raw materials for the development of chemical and biochemical processes. Acid hydrolysis of peat yields soluble carbohydrates which can be utilised as fermentation media. In this work, Sphagnum peat moss was hydrolysed under various conditions of H2SO4 concentration, retention time, temperature, peat concentration, peat particle size distribution and original moisture content in the peat. The results suggest that mild conditions of hydrolysis, which will minimise possible negative effects on other nutrients available in peat, are adequate for the release of the carbohydrates present in peat. It was found that peat particle size distribution and original moisture content as well as peat concentration will also affect the yield of carbohydrates obtained.
Equalisation of specific growth rates for syntrophic associations in batch culture
Authors: Powell Godfrey E.
Published: July 2010

This paper describes an aspect of the growth dynamics exhibited by a ‘tight’ syntrophic association of two species in batch culture. Species X utilises substrate S and forms a product P. The substance P both inhibits the growth of X, by virtue of the thermodynamic back reaction, and constitutes the growth‐limiting substrate of the organism Y. It is predicted that the resulting dynamical balance in the level of P results in an equalisation of the specific growth rates of the two populations. It is demonstrated that the equalisation of specific growth rates is a characteristic property of tight syntrophic associations in general, and occurs whenever the growth dependencies on substances S and P satisfy certain qualitative conditions.
The influence of gas inlet design on gas hold‐up values for water and various solutions in a loop‐type air‐lift fermenter
Authors: McManamey William J. , Wase D. A. John , Raymahasay Sugat , Thayanithy Kuganakathasan
Published: July 2010

Gas hold‐up was measured in an external loop air‐lift fermenter for air in water, in sodium chloride and sodium sulphate solutions (concentrations between 0.025 and 1.0 kmol m−3), in glucose solutions (0.025 to 0.25 kmol m−3), sodium carboxymethyl cellulose (CMC) solutions (0.1, 0.2 and 0.5 mass %) and in suspensions of cellulose powder in water. Gas superficial velocities were up to 0.03ms−1. Two types of gas spargers were used: one had six holes each of 1.6mm diameter, the other was of porous metal, which produced very small bubbles. Porous metal spargers with different diameters were also used, to alter the fraction of the cross‐sectional area of the riser which was aerated (the ‘fractional aerated area’). The use of dimensionless gas velocities, obtained by dividing the superficial gas velocities by a characteristic velocity for each of the non‐Newtonian liquids and solid suspensions, made possible a general correlation between gas hold‐up, dimensionless gas velocity and the fractional aerated area, in bubbly flow conditions. The characteristic velocities for the electrolyte solutions could be related to the concentrations of the electrolytes. No general correlation could be obtained for gas slug‐flow conditions, although theoretically‐based relationships represent the results for each liquid. Gas slug‐flow was observed for the non‐Newtonian CMC solutions for most of the gas rates used at the lower concentrations; only at the highest concentration was bubbly flow found over a wide range of gas rates.
Functional properties of proteins in foods
Authors: Wilding Peter , Lillford Peter J. , Regenstein Joe M.
Published: July 2010

The measurement of functionality of protein food ingredients has developed somewhat haphazardly, probably due to the wide range of proteins used as ingredients and the diversity of foods. Studies of the physiochemical properties of proteins should enable prediction of a proteins response to process environments and prove more fruitful than many of the empirical measurements of functionality. The effects of pH, salt type and concentration on the phase behaviour of the oilseed globulin and arachin, demonstrates the complexity of protein solubility and the inadequacies of simple tests that have arisen. Studies of the effects of salts and conditioning on meat fibres, coupled with measurement of the location of water in pellets from water holding tests enable the latter to be applied with increased confidence. Comparison of the endothermic transitions observed on heating with the development of storage and loss moduli allow the contributions of domains of skeletal muscle myosin to gel structure to be investigated.
Modification of a novel protein product
Authors: McNairney James
Published: July 2010

The production of single cell protein (SCP) on an industrial scale has now been established using the ICI ‘Pruteen’ process. An economic process for the reduction of nucleic acid in the product has been developed: potentially it could be used to produce a protein concentrate suitable for human consumption. Controlled enzymic hydrolysis of this concentrate yields a range of protein products with improved functional properties.
Control of the proteolytic reaction and of the level of bitterness in protein hydrolysis processes
Authors: Adler‐Nissen Jens
Published: July 2010

A generally acknowledged problem encountered in the use of enzymic hydrolysis for modification of food proteins is the formation of bitter taste. The bitter taste can be ascribed to hydrophobic peptides and results from the degradation of the protein substrate. The control of the level of bitterness is therefore to a large extent dependent on the control of the proteolytic reaction itself. Two methods for monitoring the proteolytic reaction are described: the pH‐stat technique and osmometry. Both methods give a quantitative expression for the degree of hydrolysis (DH) which is the percentage of peptide bonds cleaved. A low bitterness can usually be ascertained by restricting DH to low values (e.g. DH 3–5%). However, in certain protein hydrolysis processes which involve separation of the insoluble material, the reaction is continued to higher DH‐values. A reduced bitterness can then be obtained by iso‐electric precipitation of bitter peptides.
Inclusion of gas in casein and leaf protein precipitate particles and its effect on particle density
Authors: Munro Peter A. , Tan Boon K.
Published: July 2010

Floating precipitates often encountered in laboratory and industrial protein precipitate handling operations include isoelectric casein precipitates, casein precipitates formed by salting‐out with ammonium sulphate, and heat precipitated leaf (lucerne) protein. These were investigated by measuring water‐free densities and the variation in particle moisture content with temperature, and for each type of protein precipitate the density of degassed particles was greater than the density of the suspending medium, though the density difference was always small. Floating protein precipitates were therefore caused by the inclusion of gas in precipitate particles. Gas bubbles are easily incorporated into protein solutions. Furthermore for many types of protein precipitate, the physicochemical changes used to cause protein precipitation also drive dissolved gas from solution. Calculations showed that the amount of gas evolved is sufficient to cause flotation of all the precipitate formed.
Photosynthetic production of Dunaliella biomass from natural salt water and carbon dioxide
Authors: Cortiñas Teresa I. , Silva Humberto J. , Ertola Rodolfo J.
Published: July 2010

A Dunaliella strain has been isolated and grown in a medium containing saline lake water. Using 40% saline water and mixture of CO2‐air (4% CO2) the algae grew with a specific growth rate of 0.073 h−1. The maximum cell concentration was 5.6 × 107 cells cm−3 which corresponded to 3.63 g dm−3 of dry biomass. Using 80% saline water, a glycerol concentration of 1.47 g glycerol g−1 of, protein was obtained which amounted to 44.3% of Dunaliella dry weight. Fermentor CO2 from a continuous yeast culture was also used as carbon source for photosynthetic growth. At 2.5% CO2 in the exit gas a decrease of the specific growth rate was observed but the final concentration attained was comparable to that obtained with CO2‐air mixtures.
Electrochemical treatment of effluents: A preliminary study of anodic oxidation of simple sugars using lead dioxide‐coated titanium anodes
Authors: Ho C. C. , Chan C. Y. , Khoo K. H.
Published: July 2010

The electrolysis of simple sugar solutions, containing 0.5% NaCl or Na2SO4, using lead dioxide‐coated titanium mesh anodes in a simple electroflotation cell indicated that electrode corrosion and dissolution of polluting Pb2+ ions from the electrode material were negligible even after prolonged use; the sugars were concomitantly electrooxidised at such anodes. The rate of electrooxidation followed linear removal kinetics and the relative ease of electrochemical destruction was in the order sucrose>maltose∼glucose. Such oxidation processes represent added advantages in the use of these electrodes in electrochemical treatment of effluent containing the sugars. Cyclic voltammetric analysis of the glucose solution indicated that oxygen evolution on the lead dioxide‐titanium anode appeared to be promoted by the presence of the sugar. A much more detailed study is required to give further insight into the mechanism of the anodic oxidation of these compounds.
Preparation and characterisation of dipotassium trizinc hexacyanoferrate (II)
Authors: Dave T. N. , Indusekhar V. K.
Published: July 2010

This paper summarises our findings on the properties and cation exchange behaviour of a new silica‐based dipotassium trizinc hexacyanoferrate (II) (DTH) prepared under varying conditions of precipitation which possesses good ion‐exchange properties. The product is characterised by i.r. spectra, thermal decomposition, X‐ray diffractogram and its ion‐exchange properties have been studied under different conditions. The separation of Rb+ and Cs+ is described.
Studies on oxidative dehydrogenation of n‐butane on bismuth molybdate‐aluminium phosphate catalysts. II. Activity and selectivity
Authors: Shenoy Subhash C. , Rao Musti S.
Published: July 2010

Olefins and diolefins are important intermediates in the petrochemical industry, and the future promises a further substantial increase in demand. Several catalysts have been formulated in the past for the abstraction of hydrogen from butenes and propylene. However, these catalysts are inefficient in the abstraction of first hydrogen from n‐butane. Bismuth molybdates (β‐ and γ‐phases) on aluminium phosphate have been found to be good catalysts for the oxidative dehydrogenation of n‐butane. Optimal conditions for the yield of (butene+butadiene) have been established in the ranges of variables studied, using response surface methodology and the following ranges of experimental conditions: temperature, 400 to 500°C; W/F (catalyst to feed ratio), 0.25 to 2.5g/(mg mol/min); butane to oxygen ratio, 0.5 to 2.0mol/min; bismuth molybdate to o‐AIPO4 ratio, 0 to 100mol/100 mol. A maximum yield of approximately 13% (butenes+butadiene) was obtained in the ranges of experimental variables studied.
Effect of selected impurities on the continuous precipitation of calcium sulphate (gypsum)
Authors: Budz Jerzy , Jones Alan G. , Mullin John W.
Published: July 2010

The effects of selected cationic and anionic impurities on the precipitation of gypsum in aqueous brine have been studied in a continuous MSMPR crystalliser. Crystal size distributions, determined by in situ Malvern laser light‐scattering measurements, were found to be bimodal. The suspected presence of agglomerates was confirmed by microscopy. Aluminium and maleate ions both enhanced the degree of agglomeration, but reduced the overall growth and nucleation rates. Contrary to expectation, fumarate ions also exerted an observable effect on both agglomeration and crystal growth.
Interaction of isobutene and methacrolein with silica‐supported uranium and molybdenum oxide catalysts
Authors: Fierro Jose Luis G. , Salazar Emilio , Legarreta Juan A.
Published: July 2010

The adsorption of isobutene (in the temperature range 309–341K) and methacrolein (in the temperature range 296–336 K) on a Mo/(Mo+U)=0.89 catalyst were studied. The equilibrium data were analysed according to Freundlich's model. The high coverages observed at lower temperatures suggest some participation of physical adsorption in the reversible adsorption. Entropy calculations showed that these adsorbed species are best described by a mobile model which assumes bidimensional translation and two rotational degrees of freedom. Isobutene is weakly chemisorbed, producing reversible species which were identified as a π‐complex formed by interaction with surface OH groups through π‐electrons (infrared bands at 1655, 1615, 1470 and 1375 cm−1), and only a small fraction of isobutene interacts strongly via lattice oxygen forming intermediate species in the oxidation reaction. However, in the presence of oxygen at 523 K a majority of the surface species are strongly held by the surface (infrared bands at 1775, 1723, 1610, 1460 and 1350 cm−1 associated to a methacrylic complex and bands at 1590 and 1538 cm−1 of carbonate‐carboxylate species).
Crushing strength as a diagnostic test for catalysts
Authors: Hutchings Graham J.
Published: July 2010

The usefulness of catalyst pellet crushing strength as a diagnostic test for catalysts is discussed with reference to examples using industrial catalysts. In particular, the applicability of the technique for (i) re‐use of partially used catalyst charges, (ii) comparison of prospective catalysts and (iii) investigation of the effect on catalysts of probable plant failures is described.
Synthesis of pyrazolo[4′,3′:5,6]pyrido[1,2‐a]benzimidazole derivatives and study of their fluorescence properties
Authors: Rajadhyaksha D. D. , Rangnekar D. W.
Published: July 2010

Synthesis of pyrazolo[4′,3′ :‐5,6′pyrido]1,2‐a benzimidazoles was achieved by the condensation of 1‐chloro‐2‐formyl‐3‐methyl pyrido[1,2‐a]benzimidazole‐4‐carbonitrile and 1‐chloro‐3‐methyl pyrido[1,2‐a]benzimidazole‐2,4‐dicarbonitrile with hydrazine hydrate and phenyl hydrazine. The fluorescence properties of the resulting compounds were studied. Some of the compounds when applied on polyester fibres as fluorescent brighteners gave excellent results.
The use of the F.p.l.c.R system in method development and process monitoring for industrial protein chromatography
Authors: Low D. K. R.
Published: July 2010

The f.p.l.c.R for high performance biomolecular purification is now widely used in laboratory and pilot scale separations, both as a means of developing new methods for purification and for analysing the purity of intermediary and final products. The speed of the technique means that it is possible to analyse fractions from a process step and to receive the results within 15–30 min. Two aspects are examined in this paper: the monitoring of protein product formation during fermentation and the analysis of fractions in large scale chromatography. The suitability of the technique in an operating process is discussed.
New electrochemical techniques applied to medicine and biology
Authors: Frew J. E. , Green M. J. , Hill H. A. O.
Published: July 2010

Rapid and reversible protein‐electrode interaction has been achieved through the appropriate design of electrode surfaces and choice of electrolyte conditions. This enabled the direct (unmediated) electrochemistry of redox proteins at a range of electrode materials to be examined. Coupling of the electrode reaction to enzymes, for which the redox proteins act as cofactors, extended the study to systems of biological significance. Electrochemical techniques are finding increasing application in clinical analysis and a new type of amperometric enzyme electrode has been devised which exploits ferrocene derivatives as mediators between enzyme and electrode. The synthesis of ferrocene‐drug conjugates permitted the development of an amperometric immunoelectrode.
Characteristics of the pH‐influenced adaptation of methanogenic sludge to ammonium toxicity
Authors: Koster Iman W.
Published: July 2010

Increasing ammonium‐nitrogen concentrations caused failure of methanogenesis at 1900‐2000 mg dm−3. After an adaptation period characterised by an almost nil methane production, methanogenesis appeared to be possible at even higher concentrations. A kinetic analysis of methane production during the adaptation process indicated that the adaptation was the result of a metabolic change in the methanogenic bacteria already present, rather than of growth of new bacteria. A high pH value causing toxic concentrations of un‐ionised ammonia during the adaptation period appeared to result in a decreased maximum specific methanogenic activity of the adapted sludge. A low pH value during the adaptation period resulted in a retarded degradation of propionic acid, probably due to inhibition of the hydrogen consuming methanogenic bacteria by undissociated volatile fatty acids, but this did not result in a decreased maximum specific methanogenic activity in the adapted sludge. The maximum specific methanogenic activity at an ammonium‐nitrogen concentration of 2315 mg dm−3 after adaptation as a percentage of that at 1000 mg dm−3 before adaptation was 31, 65 and 61% for a pH during the adaptation period of 7.6, 7.25 and 7.0 respectively. Except for the sludge which was maintained at pH 7.6 during the adaptation period, after adaptation the maximum specific methanogenic activity at an ammonium‐nitrogen concentration of 2315 mg dm−3 was higher than the maximum specific methanogenic activity at an ammonium nitrogen concentration of 1900 mg dm−3 before adaptation.
Liquid phase oxidation of acetophenone to phenylglyoxal by selenium dioxide alone or with aqueous nitric acid
Authors: Sharma Virendra K. , Chandalia Sampatraj B.
Published: July 2010

The liquid phase oxidation of acetophenone to phenylglyoxal using selenium dioxide was carried out at 90°C in dioxane or ethyl alcohol with 10% (v/v) of water as a solvent with a 2:1 molar ratio of acetophenone to selenium dioxide. The yield of phenylglyoxal was more than 98% based on acetophenone and the efficiency of utilisation of selenium dioxide was as high as 99%. A novel process version based on the oxidation of acetophenone by aqueous nitric acid in the presence of selenium dioxide as a selective catalyst in a redox cycle was also considered with a view to changing the use of selenium dioxide as a stoichiometric oxidising agent to that of a catalyst, and it was found to be attractive.
Synthesis, spectral behaviour and application of oxazolo/imidazolo pyrimidine cyanines
Authors: Koraiem A. I. M. , Khalil Z. H. , Abu El‐Hamed R. M.
Published: July 2010

New asymmetrical 2‐monomethine cyanine dyes (IIIa—d, IVa—c) and dicationic cyanines(VIIa,b) incorporating oxazolo/imidazolo(3,4‐d)pyrimidine were prepared. The new cyanines were identified by spectral determination. The applications of these dyes in the protometric titrations of acids and bases were investigated. Bactericidal and fungicidal activity of selected cyanines (Ia, IIa, b, IIIb, IVb, c, V, VI and VIIb) was tested.
The effect of operating conditions on the response of a differential enzyme thermistor
Authors: Hubble John
Published: July 2010

The performance of a low cost differential enzyme thermistor system was studied. Initial results from physical characterisations showed the interdependence of operating parameters (flow rate and ambient temperature) on detector sensitivity. Subsequent work demonstrated the detection of urea using an immobilised urease column.
n‐octane dehydrocyclisation on monofunctional and bifunctional Pt/Al2O3 catalyst
Authors: Ako Churchill T. , Susu Alfred A.
Published: July 2010

The dehydrocyclisation of n‐octane to iso‐octane, ethylbenzene and o‐, m‐ and p‐xylene was investigated on monofunctional (non‐acidic) and bifunctional (acidic) Pt/Al2O3 catalyst in a microcatalytic reactor with hydrogen as carrier at 1.8 atm and 563–673 K. On bifunctional Pt/Al2O3, the total conversion of n‐octane started from a high value and decreased with increasing temperature for all pulse sizes investigated. The primary product of n‐octane conversion on acidic Pt/Al2O3 was iso‐octane. The product yield‐temperature profiles showed a large initial production of iso‐octane which decreased to a minimum as the catalyst temperature increased due to its conversion to ethylbenzene and o‐xylene. On non‐acidic Pt/Al2O3, the total conversion of n‐octane increased initially and then went through a maximum as the catalyst temperature increased. The primary products of the reaction were found to be ethylbenzene and o‐xylene, indicative of the activity of the metal to effect these ring closure reactions.
Removal of ethene to very low concentrations by immobilised mycobacterium E3
Authors: Van Ginkel C. G. , Welten H. G. J. , De Bont J. A. M. , Boerrigter H. A. M.
Published: July 2010

Removal of ethene to concentrations below 1 vpm from the air in storage facilities is necessary to prevent the deterioration of stored fruits, vegetables and flowers. Ethene‐utilising Mycobacterium E3 organisms are able to oxidise ethene to these low concentrations. Ethene was oxidised at the same rate by organisms immobilised on lava or perlite as it was by the suspension of cells. The residence times in a gas/solid bioreactor necessary to convert 66% of the ethene with an initial concentration of 3.2 vpm, and with cell loads on lava of 0.72 or 0.36 mg protein g−1 support, were 15 s and 33 s respectively. Mycobacterium E3 organisms immobilised on lava lost half of their activity in 250 h while organisms immobilised on perlite lost half of their activity in 60 h. Although the operational stability of the biocatalyst should be improved and the biocatalyst is only suitable at temperatures above 10°C, the application of ethene‐utilising bacteria in a gas/solid bioreactor appears attractive.
Preparation and study of functionalized polymers containing pendent pesticide‐active groups
Authors: Akelah A. , Hassanein M. , Selim A. , Rehab A.
Published: July 2010

A number of pesticide monomers containing pentachlorophenol as active group attached to vinyl groups, through oxyethylene as spacer group, have been prepared. The resulting monomers were homopolymerized under free‐radical conditions and also copolymerized with styrene and 2‐(2‐hydroxyethoxy)ethyl methacrylate to introduce hydrophobic and hydrophilic nature to the resulting polymers. In addition, crosslinked copolymers were prepared by using different ratios of divinylbenzene.

Data on the pentachlorophenol released through hydrolysis show that the degree of crosslinking, the hydrophilicity and the spacer group, as determined by the chemical structure and the polymer composition, as well as the pH, time and temperature appear to be major factors governing the rate at which a given polymer undergoes hydrolysis.
Analysis of gas absorption accompanied by a zero‐order chemical reaction in a liquid‐foam film surrounded by limited gas pockets
Authors: Bhaskarwar Ashok N.
Published: July 2010

Gas absorption accompanied by a zero‐order chemical reaction in a finite liquid‐foam film has been analysed to obtain expressions for the amount of gas absorbed and for fractional absorption in such a film. These equations may be readily incorporated into a single‐stage model of a foam‐bed reactor to extend it to chemisorption with zero‐order kinetics. The equations for physical absorption result naturally from a special case.
The removal of heavy metals in anaerobic upflow sludge blanket reactors
Authors: Mehrotra I. , Alibhai K. R. K. , Forster C. F.
Published: July 2010

The continuous removal of heavy metals by the biological solids in an anaerobic reactor has been examined. The metals used were chromium (III), zinc and lead. Both competitive and non‐competitive removal was studied. The results were evaluated in terms of adsorption isotherms and were compared with earlier batch studies. This suggested that the sludge acted as a cation‐exchange material, with chromium having a much lower binding intensity than lead and zinc. The data also suggest that the nature of the sludge surface is of considerable significance in determining the capacity and intensity of binding. The effect of the metals on biogas formation was also examined. This showed that inhibition of the gas formation was a function of the metal concentration and that the relative toxicities appeared to be zinc > lead > chromium.
Solution thermodynamic study of several hydrocarbons in γ‐butyrolactone and ethylene glycol mixtures by GLC
Authors: Zainel Hanaa A. , Bender Ali O. , Manook Takoohi , Talib Eman K.
Published: July 2010

The gas—liquid chromatographic technique was used to determine the thermodynamic properties of solutions at infinite dilution for binary and ternary systems of five normal paraffins (C5–‐C9), cyclohexane, benzene and toluene with γ‐butyrolactone and ethylene glycol mixtures. A combination solvent of 50 mol % of γ‐butyrolactone and ethylene glycol was shown to have the highest selectivity towards aromatic hydrocarbons.
Reduction of nitroaromatics with poly(vinylpyridine) complexes of palladium(II) and platinum(II)
Authors: Saha Chitta R. , Bhattacharya Somnath
Published: July 2010

Palladium(II) and platinum(II) anchored to 2‐ and 4‐vinylpyridine polymers of different molecular weights were used for the dihydrogen reduction of various nitroaromatics and benzaldehyde in ethanol at 50°C. Palladium(II) complexes were far more effective than their platinum(II) analogues and the activity decreased with increasing molecular weights of the polymers. The nitroaromatics were selectively and almost completely reduced to the corresponding anilines. During reduction, the orange palladium(II) complexes changed to voluminous green precipitates, which could be used repeatedly and preserved for a long time without any loss of activity. A rate equation of the type: rate = K[Cat] [H2] has been derived and a reduction mechanism has been proposed on the basis of experimental results and kinetic data.
Pore diffusion and external mass transport during dye adsorption on to Fuller's earth and silica
Authors: McKay Gordon , Otterburn Michael S. , Aga Jamal A.
Published: July 2010

The adsorption of dyes on to Fuller's earth and silica has been studied. A mass transfer model has been developed to describe the adsorption process based on external mass transfer and internal pore diffusion. Theoretical concentration decay curves have been predicted using the model and compared with experimental decay curves.
Adsorption of 2,4,5‐T by active carbons from aqueous solution
Authors: Gómez‐Jimenez Lourdes , García‐Rodríguez Antonio , de Dios López‐González Juan , Navarrete‐Guijosa Antonio
Published: July 2010

The adsorption isotherms of 2,4,5‐trichloroacetic acid (2,4,5‐T) on activated carbons from aqueous solution have been obtained at several temperatures (10 to 50°C). The activated carbons used were Merck (No. 2514) and another one prepared from almond shells (C‐A‐14).

Monolayer capacities, XM, were obtained by applying different theoretical models, such as BET, Langmuir and López‐González, to our data. The XM values were of the order of 10−3 mol g−1, being the lowest corresponding to the Merck sample. Surface areas of the two carbon samples, accessible to the molecules of 2,4,5‐T, have also been determined as well as some thermodynamic data corresponding to the adsorption process.
The use of reactive dyes in protein separation processes
Authors: Stead C. Vivian
Published: July 2010

The salient points of the chemistry of triazine based reactive dyes judged to be of interest to biochemists are summarised and the various alternative reactive systems and chromophores used in reactive dyes outlined. The development of the use of reactive dyes in dye affinity chromatography is discussed, parallels being drawn between textile dyeing and immobilisation techniques to provide suggestions for improvements in technique. The properties of the matrix are considered and structural features in the dye responsible for protein attraction analysed. The recent tailoring of dye structures to enhance utility in dye affinity chromatography and progress in the scaling up of high performance liquid affinity chromatography is reviewed.
The synthesis of fused and pendant pyrazole heterocyclic compounds from 5‐amino‐3‐methyl‐1‐phenylpyrazole and their evaluation as fluorescent brightening agents
Authors: Tagdiwala Prakash V. , Rangnekar Dinesh W.
Published: July 2010

5‐Amino‐3‐methyl‐1‐phenylpyrazole (1) has been condensed with EMME (2a) and EMCA (2b) and the resulting ethyl 5‐aminoacrylates (3a–b) cyclized to pyrazolo[3,4,‐b]pyridines (4a–b). 3‐Methyl‐1‐phenylpyrazol‐5‐yl diazonium salt (7), prepared from (1) was coupled with tobias acid (8) and 2‐methoxy‐6‐aminoquinoxaline (9) to get the corresponding O‐aminoarylazo and heterylazo dyes (10) which were oxidatively cyclized to 2‐N‐(3‐methyl‐1‐N‐phenylpyrazol‐5‐yl)‐1,2,3‐triazolo[4,5‐a] naphthalene and [4,5‐f] quinoxaline derivative (11). The spectral properties of the compounds (4a–b, 5, 6, 11a–b) were studied.
Some aspects of electrochemical engineering
Authors: Goodridge Francis
Published: July 2010

After a short discussion of the concept of electrochemical engineering, the immediate history of electrochemical process engineering (EPE) is briefly mentioned. Topics then considered are electrolytic reactor design, process modelling and optimisation, and the development and scale‐up of electroorganic processes. The article concludes with an assessment of the present state of EPE.
Flotation of perrhenates with cationic surfactants: Effect of surfactant's structure
Authors: Charewicz Witold A. , Walkowiak Wladyslaw , Beger Jörg , Schiefer Horst , Jacobi Renate
Published: July 2010

An experimental investigation is presented on the flotation of perrhenate anions from diluted aqueous solutions (5.10−5 M) with numerous cationic surfactants of systematically varying molecular structure. Alkyltrimethyl‐ammonium bromides, alkoxycarbonylmethyl‐trimethylammonium chlorides, alkoxycarbonylmethyl‐dimethylbenzylammonium chlorides, ethoxycarbonylmethyl‐dimethylalkylammonium chlorides, N‐substituted dodecylamines, and diquaternary ammonium bromides were investigated at their initial concentrations in the feed solution, 1.10−4 M or 2.10−4 M. It was found that both the length of the main hydrocarbon chain and of the short hydrocarbon groups govern the affinity of a cationic surfactant towards perrhenate anions. In order to achieve the effective flotation of perrhenate or similar anions the value of C:N atomic ratio for a tertiary or a quaternary ammonium surfactant should be in the range 15 to about 26. This value can be used as a primary criterion for the sufficient flotation capability of an alkylammonium surfactant.
Effects of changes in agitation rate on steady‐state penicillinase titres in continuously‐cultivated Bacillus cereus
Authors: Wase D. A. John , Patel Yatish R.
Published: July 2010

Increases in agitation rates at a constant dilution rate in aerobic continuous culture of Bacillus cereus furnished corresponding increases in extracellular penicillinase titres. The ratio of titre to biomass supported by the apparatus increased when the agitation rate was raised, even if the medium was diluted to half its original concentration. Potential causes of the phenomenon are discussed.
European federation of biotechnology: Achievements and the future of European biotechnology
Authors: Hambleton Peter
Published: July 2010

This Society of Chemical Industry Biotechnology Group Symposium held on 26 January 1987, at the SCI in London, aimed to review the achievements of the European Federation of Biotechnology (EFB) and consider its role in the future of European biotechnology.
Production of acid from cocoa sweatings and its use for coagulation of natural rubber latex
Authors: Sarath‐Kumara Subaddarage J. , Jansz Errol R. , Mendis Leslie P. , Tillekedratne L. M. Kirthi , Wickremasinghe L. Kirthi G.
Published: July 2010

Cocoa sweatings drain off during the fermentation of cocoa beans and are normally a waste. These sweatings were converted to ethanol and then to a mixture of acids by successive fermentation by yeast and bacteria. Of the acid formed, 25 to 50% was non‐volatile and was unidentified. The acid was used to coagulate rubber latex to form RSS No. 1 smoked sheet rubber which was similar to rubber from latex coagulated with formic acid.