bluuebunny/crossref_metadata_2025_split huggingface dataset:
Prediction of costs in continuous fermentations
Authors: Trilli Antonio 
Published: July 2010

AbstractFrom 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

AbstractIn 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

AbstractProduction 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

AbstractMethods 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

AbstractMolar 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

AbstractWe 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

AbstractThe 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

AbstractA 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

AbstractThe 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

AbstractWhen 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

Abstract3‐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

AbstractThe 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

AbstractStrontium 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

AbstractThe 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

AbstractMowrah seed (Madhuca latifolia) mealMeal 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

AbstractThe 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

AbstractThe 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

AbstractBiotechnology 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

AbstractProduction 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

AbstractA 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

AbstractAn 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

AbstractVarious 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

AbstractA 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

AbstractThe 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

AbstractAn 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.