bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of some adsorption isotherms on calcium silicate hydrates
Authors: Bye Gerald C. , Chigbo Gilbert O.
Published: July 2010

Tricalcium silicate was hydrated in suspension at a water/solid ratio (w/s) of 9 and as a paste at a w/s of 0.7. Water contents after outgassing at room temperature were 23–25% for the suspension hydrates and 19–20% for the pastes. Outgassing was standardised so that subsequent increases in BET nitrogen surface area were small even when the pumping time was doubled. Nitrogen adsorption isotherms were similar for both types of product except for the greater volume of mesopores in the suspension hydrates filled at relative pressures greater than ca 0.9p0(rp > 100 Ǎ). Electron microscopy suggested that the additional uptake of nitrogen involved capillary condensation between bundles of fibrils. Adsorption at low relative pressures would have occurred principally between the fibrils which were of the order of 20 Ǎ thick. Pore sizes could be seen to extend continuously from the mesopore to micropore range and the fact that all the isotherms contained a hysteresis loop closing with an abrupt desorption at ca0.44p0 was regarded as a property of liquid nitrogen rather than as an indication of the pore size distribution. A more quantitative indication of the pore size range present was obtained using the αs method with standard data for Fransil (silica). Plots for pastes were similar to those for suspension hydrates indicating a similar texture accessible to nitrogen in the pastes at the high w/s used. In order to characterise further the surface of the hydrates argon and carbon dioxide adsorptions were determined and the data compared using the Frenkel–Halsey–Hill equation.
Effect of thermal treatment on Egyptian rice straw hardboard
Authors: Fadl Naim A. , Sefain Magdi Z. , Rakha Mohomed
Published: July 2010

The effects of thermal treatment on the bending strength and water resistance of Egyptian rice straw hardboard manufactured with, or without, different amounts of resins, were investigated. The bending strength falls with increase in heating time and temperature for samples up to 1.5% resin; whereas hardboard with 3% resin showed an initial improvement in bending strength after heating at 140, 160 and 180°C. Heating samples at 200°C drastically reduces bending strength. Water resistance of all samples was improved by heat treatment.
Reactions of substituted anthracenes with nitric acid
Authors: Morley John O.
Published: July 2010

The reactions of sodium anthracene‐1‐ and 2‐sulphonates and disodium anthracene‐1,5‐ and 1,6‐disulphonates with concentrated nitric acid at 100°C lead to the formation of the corresponding anthraquinonesulphonates in good yield. Similarly, 1,5‐dichloroanthracene gives 1,5‐dichloroanthraquinone. In contrast, disodium anthracene‐1,8‐disulphonate, 1,8‐dichloro‐ and 1,4,5,8‐tetrachloro‐anthracene and sodium 4‐5,dichloroanthracene‐1‐sulphonate react under the same conditions to give the appropriate substituted 9,10‐dihydro‐9‐hydroxy‐10‐oxoanthracene (oxanthrone) as the major product.
Influence of inorganic salts on the hydration of tricalcium silicate
Authors: Kondo Renichi , Daimon Masaki , Sakai Etsuro , Ushiyama Hiraotaka
Published: July 2010

The influence of various chlorides and potassium salts on the hydration of alite (3CaO·SiO2solid solution) has been studied by conduction calorimetry and an explanation based on diffusion experiments in hardened Portland cement is presented. The mechanism of the action of inorganic electrolytes on cement hydration was also investigated. In hardened Portland cement the diffusion rate of the Cl−ion was greater than that of the coexisting cations. The accelerating effect of inorganic electrolytes was dependent mainly on the mobility of anions. The higher the anion mobility, the greater was the accelerating effect on the hydration. It is shown that the hydration of alite is a topochemical reaction and that the rate of hydration of alite is controlled by the rate of the dissolution of Ca2+or OH−ions into a liquid phase. It is concluded that the dissolution of OH−ions from the hydrate layer around the cement particle is increased when the reciprocal diffusion action of the anion accelerates the hydration.
Spectroscopic investigation of some derivatives of oxycellulose in cadoxen solution
Authors: Blair Henry S. , Cromie Ronald
Published: July 2010

Condensation methods for the estimation of carbonyl groups in oxycellulose are briefly reviewed. The u.v. absorption spectra of solutions of oxycellulose and some of its derivatives in cadoxen have been examined. The results show that solutions of oxycellulose, its semicarbazide derivative and its thiosemicarbazide derivative are unsatisfactory for the spectrophotometric determination of carbonyl content, whereas the phenylhydrazine derivative may be used for an approximate determination; p‐nitrophenylhydrazine however is shown to be an excellent reagent for this determination.
Prediction of costs in continuous fermentations
Authors: Trilli Antonio
Published: July 2010

From a development of the theory of the cost of continuous fermentations, the unit cost of any given product (e.g. biomass, primary or secondary metabolites) as a function of time can be predicted. For any given system there is a particular value of the dilution rate at which the unit cost of product will not change with fermentation time. At dilution rates higher than the critical one the unit cost of growth‐linked products (e.g. biomass) will decrease with time, while that of non‐growth‐linked products (e.g. penicillin) will increase with time. The converse will happen at lower dilution rates. In all cases the unit cost will tend towards a finite, fixed value. Two numerical examples are presented and the relevance of these findings to the problem of estimating a priori the convenience of a continuous fermentation process is discussed.
Noble metal catalysis. IV. Products from benzyl alcohol decomposition
Authors: Fenton Donald M. , Fett E. Reinold , Schluter Eugene C.
Published: July 2010

In the presence of the noble metal chlorides of period VIII, benzyl alcohol disproportionates to benzaldehyde and toluene. The benzaldehyde can either decar‐bonylate to benzene or disproportionate to benzyl benzoate. The order of catalyst activity is Pd > Rh > Ru. Benzyl alcohol also dehydrogenates to benzaldehyde or dehydrates to dibenzyl ether. The order of catalyst activity is Ru > Rh > Pd. In the absence of chloride, or in the presence of triphenylphosphine, the order across the periodic chart is not completely maintained.
The fermentative production of magnamycin by Streptomyces halstedii
Authors: Abou‐Zeid Abou‐Zeid A. , El‐Diwany Ahmed I. , Salem Mohamad H.
Published: July 2010

Production of magnamycin in different fermentation media by Streptomyces halstedii was studied to select the most suitable for the formation of the antibiotic. Two distinct phases were observed during the fermentative production of magnamycin. The first phase was characterised by vegetative growth, while the second phase was distinguished by formation of the antibiotic. The optimum initial pH value of the medium was 6.12. Glucose was used as carbon source. The best concentrations of glucose and starch supporting biosynthesis of magnamycin were 8.0 and 15.0 g/litre respectively. Soyabean meal was the most suitable organic nitrogen source. The most suitable concentrations of soyabean meal, yeast extract and corn steep liquor were 8.0, 2.0 and 16.0 g/litre respectively.
Solid‐phase acylating agents. Part II. The preparation and reactions of acetyl polystyrenephosphonates in aqueous solution
Authors: Laird Robert M. , Spence Michael J.
Published: July 2010

Methods of preparing acetylphosphonate acylating‐agents from cross‐linked polystyrenephosphonic acid ion‐exchange resins and reactions with aqueous aniline solutions are described. Unlike the acetyl sulphonate resins described in part I,1 the direct reaction of aniline with the acetyl phosphonate groups accounts completely for the acetylation of this base by this reagent. Results give a 40–50% conversion of aniline in aqueous solutions by either batch or flow reactions, but indicate that higher yields are possible for the latter method.
Excess enthalpy, volume, and gibbs free energy; and viscosity of acetonitrile‐methylcellosolve mixtures
Authors: Chandak Badri S. , Nageshwar Gorind D. , Mene Purashotam S.
Published: July 2010

Molar excess enthalpies of mixing at 48.2°C, and molar excess volumes at 40°C were measured for acetonitrile‐methyl cellosolve system using an isothermal phase change calorimeter and a glass dilatometer respectively. Molar excess Gibbs free energies were calculated from the isothermal vapour‐liquid equilibrium data obtained in a circulation still at 70, 60 and 48.2°C. Complete isobaric vapour‐liquid equilibrium data at 1 atm pressure are also reported. The kinematic viscosity of binary mixtures were measured at 40°C with an Ostwald viscometer. The VLE data are corrected for vapour phase nonideality, tested for thermodynamic consistency and correlated by Wilson equation. The viscosity data were correlated by McAllister and excess function models.
Liquefaction of lignohemicellulosic waste by processing with carbon monoxide and water
Authors: El‐Saied Houssni
Published: July 2010

We have liquefied lignohemicellulose, from waste black liquor, by using a carbon monoxide and water process, without using carrier oil or catalyst and aiming to produce heavy oil. Most of the liquefying reactions seem to be essentially complete in about 10 min, under the optimum conditions. Increasing the reaction temperature from 250 to 440°C raises the yield of the heavy oil from 20 to 80%. At relatively low temperatures, the same high yield of the oil was obtained by addition of different alkalis to the reaction medium in a low concentration. With addition of calcium hydroxide at a Ca/C mole ratio of 6 × 10−3 (where Cas moles of added calcium and C is moles of organic carbon in the lignohemicellulose) the yield of the heavy oil was 80%, which was about 49% without any additives and at the same reaction conditions. The grass lignin gave higher yield than the woody lignin, obtained from cotton stalks. For benzene soluble products, which were obtained from liquefaction of lignohemicellulose, the atomic H/C ratio was high and had values of 1.0 to 1.3.
Cohesive energy density of polar and non‐polar liquids
Authors: Rawat Bachan S. , Gulati Indar B.
Published: July 2010

The cohesive energy densities of polar and non‐polar liquids have been correlated with new parameters, estimation of which need no experimental data. The correlation has been tested for nine different series of compounds using data reported in the literature. The maximum deviation is found to be less than 2.5%.
An analysis of the relative errors in measuring the number of theoretical plates in a continuous distillation column
Authors: Mussche Marcel , Verhoeye Lucien
Published: July 2010

A general error function is derived which permits an examination of the accuracy of the heat of evaporation, the relative volatility, the analysis of the samples and the internal reflux ratio on the estimate of the number of theoretical trays required for a given change of the composition in a continuous rectification column. The error function published by Peacock can be derived as a special case. The examination shows that the accuracy of the estimate is mainly determined by the accuracy of the internal reflux ratio and especially the analysis of the samples. The best range for experiments is situated around an internal reflux ratio of one. An increase in relative volatility narrows this experimental range.
Vapour phase oxidation of acrolein to acrylic acid on mixed oxides as catalyst
Authors: Malshe Vinod C. , Chandalia Sampatraj B.
Published: July 2010

The vapour phase oxidation of propylene to acrylic acid is generally carried out by a two step process, involving acrolein as an intermediate. In this work, the kinetic data on the second step of the process, i.e. the oxidation of acrolein to acrylic acid were obtained using a catalyst containing oxides of antimony, nickel and molybdenum. The effects of temperature, space time and concentration of acrolein and oxygen on the yield and conversion to acrylic acid were studied, and the most suitable conditions were determined for the process. Carbon dioxide was the major by product in the reaction. The formation of acrylic acid and carbon dioxide were correlated by suitable rate expressions.
The solubilities of Fe, Ni, V and Na salts in concentrated aqueous H2SO4 solutions at temperatures between 400 and 460 K
Authors: Halstead W. David , Lovey Bernard F.
Published: July 2010

When residual fuel oil, which contains up to 4 wt% S, is burned in boiler plant, H2SO4 is formed which condenses as aqueous solutions (65–90 wt% H2SO4) on surfaces in the cool back‐end. The oil contains traces of other elements, in particular Na, V, Fe and Ni, which also deposit on these surfaces as either sulphates (Na, Fe, Ni,) or oxides (V). When designing techniques to control acid deposition and the corrosion which it subsequently causes, account must be taken of the degree to which the acid properties can be modified by taking these compounds into solution. A series of measurements of the solubilities of relevant compounds in acid solutions within the appropriate ranges of concentration and temperature (400–460 K) have been made. Sodium sulphate has by far the highest solubility (55 wt% in a solution originally containing 85 wt% H2SO4 at 423 K). Of the other compounds considered, only V2O5 exhibits a solubility of more than 2 wt%; for example, at 463 K, in 75 wt% H2SO4, solutions containing up to 16 wt% V2O5 can be formed. Solutions with up to 23 wt% V2O5 can be stabilised by the presence in solution of small amounts (∼0.5 wt%) of Fe3+ ions. The structure of these solutions is discussed.
A convenient preparative method of 3‐hydroxy acids, and the reaction of 3‐hydroxy acids with acidic materials
Authors: Fujita Tsutomu , Suga Kyoichi , Watanabe Shoji , Yanagi Ryuichi
Published: July 2010

3‐Hydroxy acids were synthesised in good yield from ketones and carboxylic acids using lithium naphthalenide in the presence of diethylamine. From cyclohexanone and propionic acid, 2‐(1′‐hydroxycyclohexan‐1′‐yl) propionic acid (I) was obtained in 98.3% yield. 3‐Hydroxy acids were treated with various acidic materials to give 3,4‐unsaturated carboxylic acids and γ‐butyrolactones. From the reaction of (I) with p‐toluenesulphonic acid or potassium bisulphate, 2‐(cyclohexen‐1′‐yl) propionic acid (II) (a 3,4‐unsaturated acid) was obtained (yield 98%), and with 97% sulphuric acid 2‐(1′‐hydroxycyclohexan‐1′‐yl) propionic acid lactone (III) was formed (93% yield). Several new γ‐butyrolactones were obtained in good yield by this method.
Acidity constants and salt formation by 1‐hydroxyethyl‐1,1‐diphosphonic acid (HEDPA)
Authors: Collins Anthony J. , Perkins Peter G.
Published: July 2010

The values for the acidity constants of 1‐hydroxyethyl‐1,1‐diphosphonic acid (HEDPA) have been calculated by a cyclic process. The fifth dissociable proton has been included in the scheme and the effects of activity corrections and overlap of dissociation processes have been explicitly included. The values obtained for zero ionic strength and 293 K are pK1, 2.01; pK2, 3.08; pK3, 7.60; pK4; 11.96; and pK5, 13.63.
Studies with inorganic ion exchange membranes—a membrane selective to strontium ion
Authors: Jain Ajay K. , Srivastava Suresh K. , Singh Raj P. , Agrawal Sushma
Published: July 2010

Strontium tungstoarsenate membrane shows response for Sr2+ and can be used to determine the activity of these ions. The response time of the membrane is a few seconds and the potentials generated are reproducible. The membrane electrode can be used for one year without any drift in potentials. The membrane was found to be more selective to Sr2+ ions than to many other of univalent, bivalent and tervalent cations. Anions also show no interference.
Anhydrocarboxylate and anhydrosulphite derivatives of α‐thiocarboxylic acids: Synthesis, purification and characterisation
Authors: Ali Mabarak , Roy Susan , Tighe Brian J.
Published: July 2010

The syntheses of anhydrosulphite and anhydrocarboxylate derivatives of α‐thioglycollic and α‐thiolactic acids by reaction of thionyl chloride and phosgene with both the parent acids and their copper salts have been examined. The preferred method, involving direct reaction with the acid, produced reasonable (30–65% depending on acid structure) yields of the required compounds. Successful synthesis of the anhydrocarboxylate of α‐thioisobutyric acid involved the simultaneous addition of phosgene and pyridine to the acid solution in order to promote formation and cyclisation of the intermediate. Characterisation of the purified products was carried out by infrared and mass spectrometry together with gas evolution techniques.
Mowrah (Madhuca latifolia) seed saponin. Toxicological studies
Authors: Mulky Mohan J. , Gandhi Vadlapatla M.
Published: July 2010

Mowrah seed (Madhuca latifolia) meal

Meal refers to solvent extracted material.

contains high levels of saponin (7%) making it unsuitable for incorporation in animal feedstuff formulations. The saponin from mowrah seed meal was isolated and purified by paper chromatography. This was used for in vitro tests as well as pharmacological and acute toxicity studies for a better understanding of its properties and toxicity. The oral, intraperitoneal and intravenous LD50 of mowrah saponins in mice are 1 g, 15–20 mg and 15 mg/kg body weight respectively. Processing of the meal to remove or inactivate the saponin will be essential prior to its incorporation in animal feeds.
Effective oxygen‐consumption rates in fermentation broths with filamentous organisms
Authors: Reuß M. , Bajpai R. K. , Berke W.
Published: July 2010

The concept of coupling molecular diffusion and reaction has been applied in the past to various biological systems with clearly defined geometrical properties like pellets and immobilised enzymes/microorganisms. This paper investigates the use of the same principle to characterise the diffusional limitation in suspensions of filamentous microorganisms. Experimental results of oxygen‐uptake measurements from Aspergillus niger fermentations in a 50 dm3 turbine‐agitated fermentor are presented with theoretical predictions of coupled diffusion and oxygen kinetics. Results are discussed on the basis of turbulence theory so that the mycelial broth can be structured in hypothetical spherical elements. Consideration of local energy‐dissipation rates in the impeller region provides reasonable explanation of the strong influence of the impeller/tank diameter ratio on the effective oxygen‐uptake rate at a given power input.
Microbial photosynthesis in the harnessing of solar energy
Authors: John Pirt S.
Published: July 2010

The shortage of fossil fuels restricts the world supply of reduced carbon compounds and energy sources. Biotechnology offers the most feasible route to renewing the supplies of reduced carbon compounds. This involves recycling of CO2 through photosynthesis. Conventional agriculture has little or no potential for supplying biomass and its derivatives on sufficient scale to offer an alternative to the fossil fuels. The agricultural wastes, on the whole, are intractable to conversion into useful carbon and energy sources and in any case are not available in amounts to provide a significant alternative to the fossil fuels. In contrast, microbial photosynthesis, optimised in photobioreactors, has vast potential to provide organic matter on a scale to match the consumption of fossil fuels. The quantitative study of microbial photosynthesis as a biotechnological route to biomass has been neglected. As a result there is a chaos of conflicting data on fundamental parameters, for example, the photosynthetic efficiency of biomass production. New photosynthetic biotechnology with fully controlled continuous‐culture systems is providing unequivocal values for the parameters. For the scale‐up of microbial photosynthesis a tubular‐loop reactor is proposed.
Biotechnology in relation to the food industry
Authors: Jarvis B. , Holmes A. W.
Published: July 2010

Biotechnology has been defined in various ways but is essentially the application of biological systems to the manufacturing industries. By implication therefore food biotechnology is the application of plant, animal and microbial systems to the production and industrial processing of food, through the development of new cultivars and livestock strains, of microorganisms with particular characteristics, and thence of new and alternative food raw materials, additives, processing aids, etc. After the publication in 1980 of the report of a joint working party on biotechnology, an appraisal was made of the awareness, interest in and potential applications for biotechnology in the food manufacturing industries. This appraisal was done, firstly, by questionnaire to food‐manufacturing companies, trade associations, etc., second, by follow‐up discussions with appropriate academic, research institute and industrial experts in the area of biotechnology and, third, as part of a Delphi forecasting exercise. Biotechnology is not new. Indeed, the food and related industries provide potent examples of the traditional application of biotechnology in areas as diverse as the brewing of vinegar and alcoholic beverages, through to the production of cured meats, the application of enzymes to the tenderisation of meats and the production of isomerose from starch. Since foods are biological materials per se, any technological treatments of food are, by definition, applications of biotechnology. There are two primary aspects to food biotechnology. Firstly, the positive application of biological processes in the development of new or improved food products and, second, the application of what we refer to elsewhere as ‘negative biotechnology’. The latter is the application of technological skills to the prevention of undesirable biological change. Both are relevant to the modern food‐manufacturing industry and must be considered in parallel. This paper is concerned specifically with the application of positive biotechnology to the food industry. The objective is to summarize some of the findings from our surveys and to indicate areas in which biotechnology developments may be applied in the food‐manufacturing industries.
Nikkomycins: Microbial inhibitors of chitin synthase
Authors: Fiedler H.‐P. , Kurth R. , Langhärig J. , Delzer J. , Zähner H.
Published: July 2010

Production of nikkomycins by Streptomyces tendae is dependent on phosphate concentration, pH and the presence of precursors or regulatory factors in the medium. In a batch‐feeding system the production of antibiotically active nikkomycins could be increased up to 3 g dm−3. The selective production of single compounds was possible by feeding precursors or using mutants of Streptomyces tendae. The whole qualitative and quantitative determination of nikkomycins was carried out with ion‐pair reversed‐phase high‐performance liquid chromatography (h.p.l.c.).
Development of the agar‐disc method for the rapid screening of strains with increased productivity
Authors: Trilli Antonio , Costanzi Italo , Lamanna Francesco , Dio Nicola Di
Published: July 2010

A simple model of colony growth and product accumulation in an agar disc was developed assuming constant rate of increase of colony biomass and a maturation‐ decay behaviour of the specific productivity of the biomass. Experimental data obtained with three erythromycin‐producing strains of Streptomyces erythreus followed the predicted behaviour of the apparent specific productivity of the colony. The latter parameter exhibited a good correlation with the specific rate of product formation observed in liquid culture. A more sensitive correlation, and higher specific productivities, were obtained with agar discs made of a fermentation‐type medium than with a maintenance‐type medium. Estimation of the colony biomass through its surface area proved to be satisfactory in the conditions adopted, though it represents a major potential source of error.
A kinetic study of precipitate flotation of Zinc(II), Cobalt(II) and Copper(II) hydroxides
Authors: Charewicz Witold A. , Basak Sergiusz
Published: July 2010

An experimental kinetic study has been completed on precipitate flotation of Zn(II), Co(II) and Cu(II) hydroxides (initial metal concentration 1 × 10−‐2M) with the anionic surfactant, sodium dodecyl benzenesulphonate (1 × 10−‐4M), at varying equilibrium pH. An original radioactive isotope procedure was applied and proved to be sufficiently accurate. Kinetic equations of Rubin and co‐workers were found to be relevant for precipitate flotation of hydroxides. From the flotation rate constant (kp) determined at varying equilibrium pH of floated suspensions it appeared that the selective flotation of individual compounds from mixed precipitate was possible as a result of the ‘kinetic effect’.
A convenient preparative method of 2,3‐dialkyi parasorbic acids from carboxylic acids
Authors: Fujita Tsutomu , Watanabe Shoji , Suga Kyoichi , Saita Masayuki , Sugahara Kotoji
Published: July 2010

Various 2,3‐dialkyl parasorbic acids were prepared from carboxylic acids. For example, 2‐methyl‐5‐pentyI parasorbic acid was prepared from hexanoic acid and propanoic acid as follows: Grignard reaction of hexanoic acid (I) with allylmagnesium chloride gave l‐nonen‐4‐one (II) and the reaction of (II) with propanoic acid (III) with lithium naphthalenide in the presence of diethylamine produced 3‐allyl‐3‐hydroxy‐2‐methyloctanoic acid (IV). From the reaction of (IV) with 97% (v/v) sulphuric acid, 2‐methyl‐3‐pentyl parasorbic acid was formed. Several 2,3‐dialkyl parasorbic acids were obtained by this method. These products may be used as perfumery materials.
Prediction of catalyst stability in naphtha reforming
Authors: Figoli Nora S. , Beltramini Jorge N. , Martinelli Eloy E. , Parera Jose M.
Published: July 2010

A method to predict catalyst activity (RON) and selectivity (ηc5+, liquid yield) of naphtha‐reforming catalysts during normal operation is described. It involves performing experiments at normal operational conditions and testing accelerated deactivation. These last experiments have a severe intermediate period at lower pressure. Carbon formation is related to time and the decrease in RON and ηc5+ is related to carbon at normal operation. The accelerated deactivation produces a similar coke to the one at normal conditions for an equal amount of coke. Therefore for each time at normal conditions there is a corresponding pressure in the accelerated deactivation test. Power law‐equations fit the data well and combining them results in the following relations: P = atb; ΔNRON = cPd; ΔNηc5+ = ePf. The coefficients a, b, c, d, e and f depend on the catalyst and are calculated from four or six experiments (half at normal conditions and half accelerated deactivation tests); b, d and f bare negative. The value of pressure for the time at which it is desired to predict catalyst activity and selectivity is calculated from the first equation. This value when applied to the second and third equations gives the activity and selectivity, respectively, that the catalyst will have after time t.
Properties of native and immobilised preparations of β‐D‐glucosidase from Aspergillus niger
Authors: Woodward Jonathan , Wohlpart David L.
Published: July 2010

The enzyme β‐D‐glucosidase from Aspergillus niger has been immobilised through its carbohydrate moiety on concanavalin A‐Sepharose and on cyanogen bromide‐activated Sepharose after aminoalkylation of the carbohydrate side chains of the enzyme. For comparison, the enzyme was also immobilised on microcrystalline cellulose through its protein moiety. High retention of activity and a decrease in Km and Vmax. were observed when β‐D‐glucosidase was immobilised by these methods. An increase in the thermal stability of the immobilised β‐D‐glucosidase preparations over the soluble enzyme was achieved if it was treated with glutaraldehyde before its adsorption on concanavalin A‐Sepharose or if the enzyme immobilised on cyanogen bromide‐activated Sepharose was subsequently treated with glutaraldehyde. Treatment of β‐D‐glucosidase immobilised on microcrystalline cellulose with glutaraldehyde hardly increased its thermal stability over the soluble enzyme.
Purification of sporidesmin by preparative high‐pressure liquid chromatography
Authors: Ronaldson John W.
Published: July 2010

An acid/alkali treatment which effects a fourfold purification of sporidesmin, making the sample immediately amenable to purification by preparative high‐pressure liquid chromatography (h.p.I.c.), is described. The alkali treatment also removes polyphenols which have been responsible for discolouration problems in previous purification methods.
Drying and storage of Solanum plant material
Authors: Grabble Phillip G. , Fryer Colin
Published: July 2010

Solasodine extracted from Solanum plants is a potential raw material for manufacture of steroids. During drying and storage of the plant material, the naturally occurring solasodine triglycosides may undergo breakdown to partial glycosides and to the aglycone solasodine; under some conditions there may be a loss of available solasodine. Previous studies of such postharvest effects show widely variable and sometimes contradictory results, possibly due to unreliable analytical procedures. Significant errors are shown to arise as a result of inadequate sample preparation, inappropriate choice of solvent and use of colorimetric or titrimetric assay. Reliable assays of glycosides and solasodine are obtained with finely ground samples, alcohol extraction and high‐pressure liquid chromatography. Experiments with these improved analytical techniques indicate that postharvest effects are almost insignificant if Solarium leaf material is well dried either at ambient conditions or below 100°C. Drying above 100°C causes severe loss of solasodine unless it is used only for the early stages of water removal. Storage of material which has not been well dried is accompanied after 2–3 weeks by glycoside breakdown and eventually by loss of solasodine.
Sorption of caesium by complex hexacyanoferrates: I. Sorption and physical properties of sodium‐copper cyanoferrates (II)
Authors: Shahbandeh M. R. , Streat M.
Published: July 2010

The preparation and properties of sodium‐copper cyanoferrate(II) for the removal of caesium from nitric acid solution are discussed. An optimum product has been obtained by reacting cupric nitrate and sodium cyanoferrate in a volume ratio of 2.1:1. The product was heated on a boiling‐water bath for 2 h before coagulation, aged for 48–72 h and then after filtration dried below 140°C for about 4 h. The maximum surface area, measured by ‘BET’ methods, was 65 m2 g−1. The maximum caesium capacity was 1.35 m‐equiv. g−1. Heating the precipitate increased the pore size to 14.5 nm and this explains the enhanced distribution coefficient (i.e. Kd∼ 900) obtained with solutions containing Cs+ (20 parts 10−6) and 4M‐sodium nitrate in 0.1M‐nitric acid.
Hydration of calcium sulphate hemihydrate in the presence of phosphoric acid and calcium oxide: I. The kinetics of hydration
Authors: Beretka Julius
Published: July 2010

A study has been made of the effects of calcium oxide and phosphoric acid on the hydration of calcium sulphate hemihydrate. The reaction was studied with weight ratios of CaO/P2O5 increasing from 0 to 5, and with two levels of P2O5 concentrations, 0.1 and 0.2%. At the CaO/P2O5 weight ratio of 1–2, the velocity constant (k) of the reaction was reduced significantly; α0, a measure of heterogeneous nucleation in the system increased 10 to 20‐fold and the period of induction (θ) was increased substantially. The presence of phosphoric acid alone, and secondary calcium orthosphate hydrate (CaHPO4.2H2O), formed in situ, strongly retarded the hydration of calcium sulphate hemihydrate. The implications of these findings on the hydration of calcined by‐product gypsum (phosphogypsum) are discussed.
Long‐chain phenols. Part 231 practical separations of the component phenols in technical cashew nut‐shell liquid (Anacardium occidentale): Distillation procedures for obtaining cardanol
Authors: Durrani Aziz A. , Davis Geoffrey L. , Sood Suresh K. , Tychopoulos V. , Tyman John H. P.
Published: July 2010

The separation of cardanol from cardol and coloured impurities in technical cashew nut‐shell liquid (CNSL) has been examined by molecular and vacuum distillation and the purity of fractions carefully assessed by thin‐layer, gas‐liquid and high‐performance liquid chromatographic analysis. A small 10‐stage rotary still (Vitamins‐Watt type) produced cardanol (99%) in approx. 58% yield with a total phenolic recovery between 80 and 90%. A falling film single‐stage still (Edwards type) gave less pure cardanol and a good total phenolic recovery. Prerequisites to avoid polymerisation in conventional vacuum distillation were wide‐bore vacuum equipment and a nitrogen leak. Excessive flask and surface temperatures resulted in only a 70% total phenolic recovery, the cardanol fractions being approx. 90% pure. With a lower flask and surface temperature, by the use of a liquid‐heating bath, the total phenolic recoveries were better than those in molecular distillation and the cardanol fractions (60 %) were 90–95 % pure. The procedure of slow addition enabled the scale of apparatus to be reduced. The distillation of hydrogenated technical CNSL appeared less satisfactory than that of the unsaturated material.
Ion‐exchange behaviour of hydrous zirconia in mixed solvents: Capacity and kinetics of exchange
Authors: Misak N. Z. , Ghoneimy H. F.
Published: July 2010

The capacity of the Li+ form of hydrous zirconia for Na+ and Cs+ increases in the presence of methanol. This may be due to the greater stability of Li+ in methanol/water than in pure water and to dehydration of Na+ and Cs+ and their stronger interaction with the exchange sites, which may facilitate their replacing Li+. The ion‐exchange capacity of zirconia for NO3−, Cl− and Br− is almost the same in aqueous solution and is not affected by addition of up to 90 % (v/v) methanol, which probably shows that these anions are electrostatically bound in zirconia without specific interactions. The internal diffusion coefficients of the Na+/H+ and Cl−/OH− systems decrease in the presence of alcohol: the decrease is highest with methanol and similar for ethanol and propan‐2‐ol. This is discussed in the light of ion solvation and alcohol penetration inside zirconia.
Improved cellulolytic activity of actinomycetes in axenic mixed fermentations
Authors: Lamot Erwin , Vandamme Erick J.
Published: July 2010

Fermentations with defined mixed cultures of cellulolytic actinomycetes or fungi and non‐cellulolytic microorganisms were performed on insoluble cellulose as well as on soluble cellulose derivatives. Degradation of insoluble Whatman‐cellulose with co‐cultures of cellulolytic actinomycetes and fungi occurred much faster and more completely than with the corresponding monocultures. Fungi appeared mainly responsible for initial cellulose degradation, while the actinomycetes subsequently metabolised the formed soluble oligosaccharides. Both fungi and actinomycetes produced active cellulases in cocultures, resulting in an increased cellulase activity of the culture filtrates as compared with the monocultures. With carboxymethylcellulose (CM‐cellulose) as a carbon source, similar results were obtained, but here the actinomycetes were mainly responsible for CM‐cellulose degradation rather than the fungi. Hydrolysis of insoluble cellulose by cocultures of cellulolytic actinomycetes or fungi with cellobiose‐utilising bacteria or yeasts was similar to that with the corresponding actinomycete or fungal monocultures. Apparently the soluble oligosaccharides, formed from cellulose by the actinomycetes or fungi, could not be utilised as a carbon source by these bacteria or yeasts, while the reducing sugar level was probably too low to allow detectable growth. With CM‐cellulose as a carbon source, the reducing sugars formed by the actinomycetes or fungi are actively metabolised by the bacteria or yeasts. Thus by keeping the readily utilisable sugar concentration very low, carbon catabolite repression of cellulase synthesis is lowered, resulting in an increased cellulase formation and improved cellulose hydrolysis.
Adsorption of ionic dyes on charred plant material
Authors: Perineau Francis , Molinier Jacques , Gaset Antoine
Published: July 2010

The adsorption of ionic dyes on charred plant material was investigated to assess the possible use of this adsorbent for the processing of dyeworks waste waters. The diffusion of the acid dye (AB 80) within the carbon particles was much slower than that of the basic dye (BR 22), as a result of the greater size of the former molecule. The rate of diffusion of the dyes increased with temperature as a result of the disaggregation of the dye molecules. This effect was more pronounced in the case of the acid dye. The L‐shaped adsorption isotherms suggest that the adsorption proceeds through ionic bonding and that the dye molecules are adsorbed flatwise on the surface of the charred plant particles; the substrate‐solute hydrophobic interactions can thus be maximum. The charred plant material used is suitable for the processing of low‐concentration effluents, as corroborated by the treatment of a BR 22 solution in a series of stirred reactors and by the decolourisation of dyebaths containing acid and basic dyes.
Sludge surfaces and their relation to the rheology of sewage sludge suspensions
Authors: Forster C. F.
Published: July 2010

An examination of activated, anaerobically digested and aerobically digested sludges has shown that their rheological characteristics are related to the surface charge carried by the component particles. This relation is controlled partly by the ionic strength of the suspending fluid and partly by the chemical nature of the sludge surfaces. Polysaccharides are known to play an important role in determining the surface charge of activated sludge. This study has shown that as the surface polysaccharide content is reduced (by the action of cellulase), so is the viscosity and indicates that surface polysaccharides are significant in determining the viscosity of activated sludge suspensions. The surfaces of other sludge types are not as well characterised and further work than described here is necessary to identify the more significant components for these sludges.
Behaviour of uranium during phosphate ore calcination
Authors: Stein Mordechai , Starinsky Avraham , Kolodny Yehoshua
Published: July 2010

During industrial calcination of phosphate rock, uranium is mobilised with changes both in location and oxidation state. Fission track micromapping of uranium under the microscope has been employed to study the precise distribution of uranium within the samples. Oxidation state ratios of U(IV) to U(VI) were determined by chemical separation followed by delayed neutron activation. The calcination process was studied both in the laboratory and in a full‐scale production kiln of the Oron plant (Israel). The phosphate ore contains about 100 parts of 10−‐6 of uranium, and U(IV) comprises 35–40% of the total U present. The uranium which was not extractable in weak acids, was evenly distributed in the apatite rock components. The study revealed that the following changes occur during the calcination process: (a) carbonate‐fluorapatite loses CO2, and recrystallises to fluorapatite. The recrystallisation process intensifies with increasing temperature, (b) Around 600°C all the uranium is oxidised to the hexavalent state, (c) Migration of uranium in the apatite fragments initiates at 800°C. On increase of temperature to around 900°C, it forms uranium‐rich phases in which it reaches 1–2 %. The uranium‐rich phases exhibit different solubilities in dilute acids, in some cases enabling its preferential leaching from the rock. Other U‐rich phases are extremely insoluble (possibly fluorite, Ca‐silicates) even in phosphoric acid, lowering extraction efficiency. Extraction yields can be improved by addition of salts (e.g. Na2CO3) which prevent the formation of insoluble U‐rich phases.
Effect of partial deactivation of Pt catalysts on the selectivity of competitive hydrogenation of olefinic substrates
Authors: Červený Libor , Kuncová Marcela , Mojžíšová Jana , Rüžička Vlastimil
Published: July 2010

The effect of partial deactivation of 10% Pt on silica gel with ethyl amine and 2‐aminoethanol on the selectivity of competitive hydrogenation of 2‐methyl‐3‐butene‐2‐ol and 1‐hexene in methanol and in cyclohexane and the effect of partial deactivation of platinum black with thallium, lead and bismuth on the selectivity of the same reaction in toluene have been investigated. The causes leading to changes in selectivity in the systems under investigation have been studied.
Oxalic acid manufacture
Authors: Dube Shiv Kumar , Vasudevan Padma , Khandelwal Bishan Lal
Published: July 2010

The manufacture of oxalic acid from waste of plants obtained from a variety of starting materials such as glucose, sugar, glycol, flour, rice straw, sarkanda (Saccharum munja), arhar (Cajanas cajan) sticks, pineapple waste, molasses, jute stick, potato pulp, peat and unsaturated hydrocarbons such as acetylene and propylene, etc., is described. The economic viability of a few processes in Third World countries based on Indian experiences are discussed.
Dehydration reactions of fructose in non‐aqueous media
Authors: Brown David W. , Floyd Arthur J. , Kinsman Richard G. , Roshanhyphen;Ali Yusuf
Published: July 2010

Procedures for the dehydration of fructose in non‐aqueous solvents using Amberlyst 15 strong acid resins and amine salts as catalysts have been developed to give hydroxymethylfurfural (HMF), hydroxymethylfurfural ethers and laevulinate esters with high carbon recoveries. These procedures allow of easy ‘scale‐up’ and recovery of catalyst and solvent.
Effect of ageing of Raney nickel on its catalytic properties for slurry phase hydrogenation of p‐nitrotoluene
Authors: Chaudhary Vasant R. , Chaudhari Sudhakar K.
Published: July 2010

The effect of different storage conditions (liquid medium, temperature, gas atmosphere and storage period) on the H2 content of Raney nickel catalyst and on its catalytic activity in the hydrogenation of p‐nitrotoluene to p‐toluidine has been investigated. The results indicate that the effect of a particular storage condition on the activity of the catalyst cannot be isolated; the activity depends on the combined effect of the storage conditions employed.
Ce(III) and IN(III) complexes of salicylideneamino acids
Authors: Mahmoud Mohamed R. , El‐Shafei Ahmed K. , Abdel‐Mawgoud A. M.
Published: July 2010

The synthesis of a new series of Ce(III) and In(III) salicylideneamino acid complexes is described. The structure of these complexes was examined and it was found that the dianions of the schiff bases are coordinated to the metal ion as O—N—O tridentate ligands. The apparent formation constant values of the prepared complexes, determined by a continuous variation spectrophotometric method, are discussed in relation to ligand molecular structure.
Cellulase activity of a thermophilic Aspergillus fumigatus (fresenius) strain
Authors: Vandamme Erick J. , Logghe Jean‐Marie , Geeraerts Herman A. M.
Published: July 2010

A thermophilic fungus, isolated from horse manure on Whatman‐cellulose CF‐11 as sole carbon source, was identified as Aspergillus fumigatus. It grew optimally at 45°C and displayed highest cellulase activity at 55°C and pH 5.0 towards a range of soluble and crude insoluble cellulosic substrates. Germination and outgrowth of the spore inoculum in carboxymethylcellulose (CMCellulose) medium was accompanied by high endoglucanase (E.C. 3.2.1.4.) activity. The cellulase complex e.g. exo‐β‐1,4‐glucanase (E.C.3.2.1.‐); endo‐β‐1,4‐glucanase (E.C.3.2.1.4.) and β‐glucosidase (E.C.3.2.1.21.) displayed quite different properties depending on whether it was formed on low or highly substituted CMCellulose. Extracellular cellulase formation followed biomass accumulation. Upon prolonged incubation cell lysis occurred which resulted in a further increase in cellulase activity. Ball‐milled crude cellulosics, such as newsprint, de‐inked newsprint, glossy writing paper, toilet paper and beech sawdust were substantially solubilised within 110 h of growth. The type of crude cellulosic material greatly influenced the pattern of enzyme production. The enzyme complex formed when A. fumigatus was grown on soluble CMC‐4M6F, displayed a different activity spectrum towards crude cellulosics compared with that formed on ball‐milled glossy writing paper. The extracellular cellulase of A. fumigatus looks promising for a rapid and substantial solubilisation and saccharification of crude cellulosics.
Origin of porosity in titania gels. Part II. Adsorptive properties of gels prepared from titanous chloride and ammonium carbonate
Authors: Ragai Jehane , Sing Kenneth S. W.
Published: July 2010

Titania gels were prepared from a master batch of hydrous titanous oxide, which was obtained by the addition of ammonium carbonate solution to aqueous titanous chloride. After oxidation of the Ti3+ to the Ti4+ oxide, the precipitate was divided into various parts for the study of the changes in surface properties produced by storage under ammonia and water and by heat treatment. The outgassed sample having the largest BET surface area and pore volume (as determined by nitrogen adsorption) was obtained by calcination in air for 4 h at a temperature of 493 K. Analysis of the nitrogen isotherm indicates that this sample was both mesoporous and microporous (BET area 284 m2 g−1; pore volume, 0.234 cm3 g−1). Increase in the calcination temperature to 613 K led to removal of the microporosity and a drastic reduction in surface area. The generation of the large surface area appears to be dependent on the formation and decomposition of a carbonato complex.
Evaluation of the DNS method for analysing lignocellulosic hydrolysates
Authors: Marsden Warwick L. , Gray Peter P. , Nippard Greg J. , Quinlan Mark R.
Published: July 2010

The dinitrosalicylic acid (DNS) method gives a rapid and simple estimation of the extent of saccharification by measuring the total amount of reducing sugars in the hydrolysate. However, it is subject to interference by citrate buffer and other substances and by the differing reactivities of the various reducing sugars. These interferences become more apparent when complex substrates such as sugar cane bagasse are employed. The paper also shows how the DNS method can be adapted for use on a Technicon Autoanalyser.
Hydrolysis of aromatic sulphonic acids in industrial effluents. I. Hydrolysis of 7‐hydroxy‐2‐naphthalenesulphonic acid
Authors: Rossinelli Luca , Thies Hans , Richarz Werner
Published: July 2010

The protodesulphonation of 7‐hydroxy‐2‐naphthalenesulphonic acid (F‐acid) was investigated in dilute aqueous sulphuric acid at temperatures of 522–553 K. The hydrolysis of the sulpho group is irreversible and F‐acid can be completely converted into 2‐naphthol in a short time. The hydrolysis rate depends strongly on the temperature and on the sulphuric acid concentration; a rate equation was derived from the experimental data.
A reaction of 3,4‐unsaturated carboxylic acids with paraformaldehyde or 1,3,5‐trioxane
Authors: Fujita Tsutomu , Watanabe Shoji , Suga Kyoichi , Kuramochi Tadao , Tsukagoshi Fusao
Published: July 2010

3,4‐Unsaturated acids were condensed with paraformaldehyde in boiling acetic acid containing a small amount of aluminium chloride to afford 2,3‐unsaturated‐δ‐lactones. For example, from 2‐(cyclohexen‐1′‐yl)caprylic acid (I) and paraformaldehyde, 2′‐hydroxymethyl‐2‐cyclohexylidenecaprylic acid lactone (II) was obtained in up to 93% yield. Several 2,3‐unsaturated‐δ‐valerolactones were obtained in good yield by this new method. These lactones may be used as perfumery materials.