bluuebunny/crossref_metadata_2025 huggingface dataset:
A simple statistical technique for the detection of specific minor impurities by infrared absorption spectroscopy
Authors: Corbett John K. , Scullion Henry J.
Published: July 2010

A technique is described which allows a simple statistical procedure to be applied to a recorded infrared spectrum to ascertain whether certain observed deviations from the spectrum of the pure substance may reasonably be associated with the presence of a specific minor impurity. No computational facility is essential, but if available, it may be readily harnessed.
Effect of cellulose fibre fines on the retention of fillers
Authors: Jaycock Michael J. , Pearson Joseph L. , Counter Raymond , Husband Frederick W.
Published: July 2010

Electrophoretic mobility measurements and retention measurements on papermaking stocks are presented for fines‐free systems and compared with the results for systems containing cellulose fines. It is shown that the cellulose fines make profound differences in the pattern of retention behaviour, and that the results may be qualitatively understood in terms of simple heteroflocculation theory.
Vanadia‐molybdena catalysts for the oxidation of 2‐picoline
Authors: Gentry Stephen J. , Jones Alan , Firth Jack G. , Watts Peter
Published: July 2010

A study has been made of the influence of catalyst composition on the gas phase oxidation of 2‐picoline over mixed vanadium and molybdenum oxides supported on kieselguhr. It is shown that the formation of partial oxidation products is associated with the existence of a mixed oxide phase. The selectivity for the formation of pyridine‐2‐aldehyde reaches a maximum when one in six vanadium(V) ions in the V2O5 lattice is replaced by a molybdenum(VI) ion. It is suggested that the origin of the selectivity is the formation of isolated (V4+‐O) species.
Interaction between aluminium dihydrogen phosphate and quartz
Authors: Morris John H. , Perkins Peter G. , Rose Alasdair E. A. , Smith W. Ewen
Published: July 2010

Thermal‐balance and differential‐scanning calorimetric studies of the aluminium dihydrogen phosphate/quartz system are reported. An interaction involving a chemical bond is demonstrated and characterised. A study of the nature of the species is reported and an unusual phosphate formula, Al(HP2O7)·2.5H2O, is characterised.
Synthesis of coloured copolyamides
Authors: Fatten Abd El‐Kader , Khalifa Abd El‐Moniem , Kaddah Ahmed M. , Abd El‐Azim Wedad M.
Published: July 2010

Coloured copolyamides were prepared by the interfacial polycondensation (IPC) method. Different acid chlorides (e.g. 4‐oxo‐1,2,3,4‐tetrahydro‐1‐naphthoyl‐1‐propionyl dichloride) were condensed with aromatic and aliphatic diamines. Viscosity and infrared measurements were used to elucidate the structure of the copolyamides formed under optimal conditions.
Liquid‐liquid equilibrium studies for separation of aromatics
Authors: Rawat Bachan S. , Gulati Indar B.
Published: July 2010

Liquid‐liquid equilibrium studies have been carried out on 11 solvents using two binary hydrocarbon mixtures for selective extraction of aromatics. The solvents used have been compared on the basis of selectivity, solvent capacity and tie line correlation curves. Tie line data have been determined for 18 systems. The selectivity and solvent power of solvents as obtained from limiting activity coefficient and tie line data have been compared. The selectivity and capacity of solvents have been related to their structure through an empirical parameter.
Time course of the levels of oxidative intermediates during methanol utilisation by Candida boidinii 11 Bh
Authors: Pilát Petr , Prokop Aleš
Published: July 2010

Growth kinetics of the methanol‐utilising yeast Candida boidinii 11 Bh in shake flasks and in a fermenter have been studied in connection with the accumulation of the oxidative intermediates, formaldehyde and formic acid. The effect of the addition of substrate, formaldehyde and formic acid during batch growth showed that formic acid may accumulate to amounts inhibitory to growth. The amount of formic acid accumulated was proportional to the initial methanol concentration. On the other hand, formaldehyde, the first oxidative product, had no effect on growth under the same conditions.
Extraction of cephalosporin C from fermentation broths via lipophilic intermediates and the production of 7‐aminocephalosporanic acid (7‐ACA)
Authors: Andrisano Renate , Guerra Guido , Mascellani Giuseppe
Published: July 2010

The extraction of cephalosporin C from fermentation broths chemically via aryl and alkylsulphonyl chlorides was studied, with the aim of developing a method which is comparable with regard to yield, but independent as to the patent from the chromato‐graphic method. A study was also carried out on the reaction conditions for the transformation of N‐arylsulphonylcephalosporin C into 7‐ACA.
Phase equilibria in systems composed of an aliphatic and an aromatic hydrocarbon and sulpholane
Authors: De Fré Raphaël M. , Verhoeye Lucien A.
Published: July 2010

Ternary liquid‐liquid equilibria of the type aromatic + non‐aromatic + sulpholane were studied. The systems cyclohexane + benzene + sulpholane, 1‐hexene + benzene + sulpholane, hexane + benzene + sulpholane and heptane + toluene + sulpholane were experimentally determined at 25, 50, 75 and 100°C. The binary vapour‐liquid equilibria sulpholane + benzene and sulpholane + toluene were also measured. The ternary data were correlated by means of the NRTL‐equation with 6 and 9 variable parameters. To overcome correlating problems the starting values of the parameters were taken from the corresponding binary liquid‐liquid and vapour‐liquid equilibria, and were varied two by two. Use of 9 parameters did not improve significantly the correlation. Generally the bottom tielines are correlated very well, while at the top considerable deviations can occur.
Effects of carbonation and hydrothermal treatments on some properties of calcium monoaluminate mortars
Authors: Mills Bernard E. , Hughes David O.
Published: July 2010

To produce suitable catalyst supports for the steam reforming of hydrocarbons, the effect of curing calcium monoaluminate in both steam and carbon dioxide has been investigated. The green strengths of steam cured samples were no higher than those of air‐cured samples, but the strengths under steam reforming conditions (850°C in steam) were very much higher. The green strengths of carbon dioxide cured samples were higher than those of air cured samples and under steam reforming conditions the strengths were similar to those of the steam cured samples. An explanation of the behaviour is proposed in terms of the hydration mechanisms and the reactivities of the decomposition products.
Isolation and properties of sulphur trioxide‐sulpholane complex
Authors: Hayashi Teruyuki , Iida Hiroko , Ogata Ikuei
Published: July 2010

The one to one complex of sulphur trioxide (SO3) and sulpholane was isolated as white needles, and the melting point, distillability, thermal stability, Raman and n.m.r. spectra were measured. It has been shown in the sulphonation of naphthalene by SO3 in 1,2‐dichloroethane that sulpholane retards the reaction far less than dioxane and rather increases selectivity for α‐sulphonation.
Reactions occurring in the organic phase during aromatic nitrations
Authors: Albright Lyle F. , Schiefferle Daniel F. , Hanson Carl
Published: July 2010

The reactions which may occur in the organic phase during mononitration of benzene and toluene under heterogeneous conditions used in industry have been studied by mixing the hydrocarbon with a solution of nitrating acid in either m‐mononitrotoluene or mononitrobenzene. Both nitration and oxidation reactions are shown to occur. A separate aqueous phase may be formed during reaction, and distribution of nitric acid into this has an important effect on reaction in the organic phase. The rate of nitration is sensitive to the presence of even traces of sulphuric acid. The ratio of mononitrotoluene isomers formed in the organic phase is the same as under heterogeneous conditions.
Kinetics of the reaction between carbon dioxide and hydrogen over a ruthenium catalyst in a continuous stirred tank reactor
Authors: Quach Thi Quy Phung , Rouleau Denis
Published: July 2010

The catalytic reaction between carbon dioxide and hydrogen over a surface coated ruthenium catalyst was investigated in a stirred tank reactor, under isothermal conditions from 200 to 300°C. The kinetic data obtained were analysed by the Hougen‐Watson method. Non‐linear least squares analysis was used to discriminate among 28 rate models. The following Hougen‐Watson type rate equation was selected.
Rhenium, tungsten and molybdenum as substitutes for plantinum in aromatics hydrogenation catalysts
Authors: Aboul‐Gheit Ahmed K. , Cosyns J.
Published: July 2010

Three metal substitutes for platinum on alumina‐supported catalysts have been investigated. These metals are rhenium, tungsten and molybdenum. In the absence of platinum, these metals are catalytically inactive. At high hydrogenation temperatures (≥100°C) rhenium, tungsten and molybdenum appear to substitute platinum up to at least 66.7, 50 and 33.3% of the platinum atoms, respectively, providing almost the same conversion as platinum. At low hydrogenation temperatures (∼50°C), the catalyst containing 0.6 wt% Pt is more active than those containing metallic combinations. At low reaction temperatures, in particular for high platinum substitution ratios, tungsten appears functionless whereas molybdenum may act as an inhibitor for platinum.
A convenient method to estimate the rate of heat evolution in fermentation
Authors: Imanaka Tadayuki , Aiba Shuichi
Published: July 2010

The estimation of heat of fermentation is discussed with reference to experimental data obtained in glucose‐, ammonia‐ and oxygen‐limited chemostat cultures of a specific bacterium and also to previous data published by other workers. Whatever the microbial or cultural conditions might be, the heat of fermentation can be easily estimated from TOD (total oxygen demand) measurement, accompanied by the concept of available electrons. If aerobic pathways are dominant in a particular fermentation, the specific rate of heat evolution, QH, can be calculated approximately from QH = Qo2 (−δHo7ast;), where − 7delta;Ho* = 106 kcal/mol O2, using only Qo2 values without the need for either TOD or calorimetric determination.
Specific Ortho‐bromination. I. Preparation of ortho‐bromo substituted benzenes
Authors: Meidar David , Halpern Yuval
Published: July 2010

A process1 for the synthesis of ortho‐bromo aromatic compounds was studied. The process is based on the blocking and shielding effect of a tertiary butyl group which is introduced on to the aromatic ring prior to bromination. The removal of the tertiary butyl group, after bromination, is accomplished by transferring it to another aromatic nucleus via an aluminium trichloride catalysed transalkylation reaction. Synthesis of six different compounds are described and a recycle process is illustrated.
Simulation of continuous counter‐current leaching of garad pods
Authors: Gasm‐el‐Seed Gurashi A. , Mulla Tag‐el‐Sir H. A.
Published: July 2010

A multiple‐batch extraction technique, usually applied in liquid‐liquid extraction, has been employed successfully to simulate continuous counter‐current leaching of tannins from garad pods. The work shows that the overall leachability using the best continuous systems could be as high as that of the batch system.
An investigation of methods for isolation of the steroidal alkaloid solasodine from native new zealand Solanum species
Authors: Weston Roderick J.
Published: July 2010

A review of methods for the isolation and hydrolysis of the glycoalkaloids in the native New Zealand species Solanum aviculare and S. laciniatum (Solanaceae) is given, together with two recommended procedures for the production of solasodine.
Ternary liquid equilibria in propionic acid‐water‐solvents systems
Authors: Rathindranath Sinha , Venkateswarlu K. , Rao R. Jagannadha
Published: July 2010

Mutual solubility and tie‐line data are presented for four ternary liquid‐liquid systems containing propionic acid, water and the hydrocarbons benzene, toluene, xylene and kerosene, at 30°C. The tie‐line data for the systems are correlated by the methods of Hand and of Othmer and Tobias, and the plait points are located by the method of Treybalet al.For all the systems the distribution of propionic acid is more in favour of the aqueous phase. Among the four hydrocarbons studied, benzene showed the highest distribution coefficient as well as selectivity.
Correlation of the boiling points of alkanols
Authors: Ambrose D.
Published: July 2010

A scheme is presented for correlation of the boiling points of alkanols with structural features. Boiling points may be estimated by the method with errors probably not exceeding 5 K.
Modification of the anionic flotation behaviour of ilmenite, magnetite, enstatite and anorthite
Authors: Abeidu A. M. , Kholeif T. S.
Published: July 2010

The key process for the separation of ilmenite from magnetite and associated silicate gangue minerals such as enstatite and anorthite was found to be pretreatment with sulphuric acid solution of pH 2 and the use of orthophosphoric acid as regulator. Sulphuric acid leached out selectively ferrous sites from crystalline lattice surfaces of ilmenite and magnetite and calcium, magnesium and aluminium sites from crystalline lattice surfaces of enstatite and anorthite. As a result, a great difference in surface properties of ilmenite and other minerals was achieved which makes selective separation of ilmenite in the presence of orthophosphoric acid quite feasible. The beneficial action of orthophosphoric acid in selective separation in an oleate medium and its detrimental effect in alkyl sulphate solution was shown to be due to the relatively high pKa of oleic acid and the extremely low pKa of alkyl sulphuric acid.
Isolation and identification of constituents of Jasminum auriculatum (Vahl) leaves
Authors: Srivastava D. N.
Published: July 2010

Jasminum auriculatum (Vahl) (family: Malvaceae) widely grown in India was analysed for its fatty acids and waxy constituents. Straight‐chain hydrocarbons (C20‐C34), fatty acids (C14‐C23) and fatty alcohols (C21‐C32) were found in the 95% aqueous ethanol extract of the leaves of the plant. Malvalic acid was the only cyclic acid identified. Hydrocarbons (C29 and C31), fatty acids (C16, C18, C18:1, C18:2, C18:3 and C22) and fatty alcohols (iso‐C26, C28 and C30) were the major components. Four polyalcohols, namely D‐mannitol, xylitol, inositol and sorbitol, have also been found in the alcoholic extract of the leaves.
Production of catalase from Rhodopseudomonas spheroides
Authors: Gallili Gilad E. , Mateles Richard I.
Published: July 2010

The large‐scale fermentation of Rhodopseudomonas spheroides L‐28, a high catalase mutant, was studied. High concentrations of cells containing high contents of catalase were obtained in a fermentor in which the culture was titrated throughout the fermentation with an organic acid. Extraction of the cells after acetone treatment resulted in a partly purified catalase suitable for industrial purposes. Increased purity could be achieved by additional purification steps.
A convenient preparative method for 1,4‐diketones from carboxylic acids
Authors: Watanabe Shoji , Fujita Tsutomu , Suga Kyoichi , Abe Haruhiko
Published: July 2010

Various 1,4‐diketones were prepared from carboxylic acids via two steps: Grignard reaction with vinylmagnesium chloride and oxidation with Jones reagent catalysed by mercuric propionate. For example, 2,5‐undecanedione was prepared from heptanoic acid via 1‐undecen‐5‐one.
The hydrogenation of aromatics on catalysts having their platinum, ruthenium and palladium replaced with rhenium
Authors: Aboul‐Gheit Ahmed Kadry
Published: July 2010

Three alumina‐supported catalysts containing 0.6% of the transition metals: platinum, ruthenium and palladium as well as combinations of each of these metals with rhenium have been studied for hydrogenating the aromatics present in a desulphurised white spirit fraction. The catalyst containing 0.6% Re, which represents complete replacement of the transition metal, appears to be completely inactive for the hydrogenation of aromatics. The relative activities of the catalysts containing 0.6% of the metals Pt, Ru and Pd at 100°C reaction temperature are of the order: 4.2:2.6:1, respectively, whereas for the 50/50 combinations of these metals with Re are of the order: 4.1:1.9:1, respectively, indicating that the replacement of Ru with Re may lower the hydrogenation activity of Ru by some 30%. The activation energies obtained for aromatic hydrogenation over the 0.6% Ru and Pd are, respectively, 6.17 and 8.83 kcal/mol, whereas they are 7.82 and 8.87 kcal/mol for the 50/50 replaced Ru and Pd catalysts, respectively with Re. On the other hand, the Pt‐containing catalysts are too active to permit activation energy calculation.
Method for the determination of oxygen transfer coefficients (KLa) with the correction for the actual cultivation conditions
Authors: Páca Jan , Grégr Vratislav
Published: July 2010

A method for determination of the volumetric oxygen transfer coefficient KLa from dynamic measurement data under conditions of both excess oxygen and oxygen‐limited growth of microorganisms is described. The KLa determination follows from the integrated form of the oxygen balance equation and involves a correction for the actual cultivation conditions during measurement.
Effect of phase composition on the binding characteristics of unfired stable dolomite refractories
Authors: Serry Mohamed A. , Girgis Lamey G.
Published: July 2010

Three batches of stable dolomite cements with different mineral compositions and fineness were prepared. The hydraulic properties of each sample were measured after curing at 100% relative humidity for 1, 3, 7 and 28 days. The results were interpreted in the light of the phase composition, fineness and curing time. The cement with the highest hydraulic properties was used as a binder for the preparation of unfired stable dolomite bodies. The changes in properties of the prepared bodies at temperatures up to 1550°C were correlated with the phase compositions.
Catalytic oxidation of methanol over molybdenum oxide–tungsten oxide
Authors: Mann R. S. , Jain S. K. , Dosi M. K.
Published: July 2010

The vapour phase oxidation of methanol to formaldehyde over molybdenum oxide, tungsten oxide and their mixtures has been investigated in an integral flow reactor at atmospheric pressure. The effect of several process variables on the conversion and yield were determined. A high conversion of 95.6% methanol with nearly 95% selectivity was obtained at 430°C. A rate expression has been derived from the kinetics of the reaction.
High pressure synthesis of terephthalic acid from p‐dichlorobenzene
Authors: Santra Manoranjan , Palit Sunanda K.
Published: July 2010

Terephthalic acid was obtained from p‐dichlorobenzene, carbon monoxide and water when the reaction was carried out in the presence of nickel iodide supported on silica gel (Ni:SiO2 = 50:50) the catalyst which showed the best catalytic activity among those tested. The maximum conversion of p‐dichlorobenzene to terephthalic acid at the optimum conditions was 14.9%.
Chromatographic determination of specific surface area of adsorbents by using the Jovanović equation
Authors: Jaroniec Jadwiga A. , Jaroniec Mieczystaw , Gawdzik Jan
Published: July 2010

A new chromatographic method for calculating monolayer capacity and specific surface area has been presented. This method is based on the Jovanović adsorption equation.
Competition for double growth‐limiting nutrients in continuous culture
Authors: Yoon Heeyoung , Blanch Harvey W.
Published: July 2010

Competition between two microorganisms in continuous culture for multiple substrates is examined. The competitive elimination principle of Gauss applies when two organisms compete for one growth‐limiting substrate. If two substrates are present, and microbial growth depends on both (double substrate limitation), then both organisms may coexist in a stable steady state. The range of microbial parameters over which this steady state occurs is examined.
Thermal decomposition of uranyl chloride hydrate
Authors: Sato Taichi , Shiota Shigeaki , Ikoma Shuji , Ozawa Fusaji
Published: July 2010

The thermal decomposition of uranyl chloride hydrate has been investigated by thermal analyses, X‐ray diffraction and infrared spectroscopy. From the results it is concluded that uranyl chloride hydrate decomposes thermally as follows:
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Effect of pretreatment on the sublimation of ammonium perchlorate
Authors: Verneker Vencatesh R. Pai , Kishore Kaushal , Kannan Malayan P.
Published: July 2010

The effects of pretreatments on the sublimation of pure ammonium perchlorate (AP) were studied by differential thermal analysis. The addition of inorganic salts (doping), or preheating, lead to desensitisation of the sublimation process, whereas it was sensitised by precompression. Sublimation increased with decrease in the particle size of the AP from 500 to 200 microns, but decreased with a further decrease in size from 200 to 100 microns. The results are interpreted in terms of gross imperfections and strain in the AP crystals.
Liquid‐vapour equilibria of binary systems of acetonitrile with chlorobenzene and n‐butyl acetate
Authors: Rao C. V. Sivarama , Rao K. Venkateswara , Raviprasad A. , Chiranjivi C.
Published: July 2010

Vapour‐liquid equilibrium data of the systems acetonitrile‐chlorobenzene and acetonitrile‐n‐butyl acetate are measured at 760 mmHg pressure. Both systems are non‐ideal in behaviour and show positive deviations from Raoulc's law. The two systems form symmetrical solutions and are well represented by single constant Margules equations.
Alkylaminoanthraquinones as dyes for polypropylene fibres
Authors: Lord W. Martin , Peters Arnold T.
Published: July 2010

The synthesis of a series of 1‐alkylaminoanthraquinones is described. In general, dyeing properties and light fastness of these compounds on unmodified polypropylene fibres improves with increase in length of the alkyl chain. The presence of the n‐octadecylamino group is particularly advantageous and a range of new dyes containing this substituent is described.
Cement forming ability of silicate minerals and polyacid solution
Authors: Crisp Stephen , Wilson Alan D. , Elliott Joseph H. , Hornsby Peter R.
Published: July 2010

A preliminary survey of the cement‐forming reactions between silicate minerals and polyacid solutions is presented. Reaction mixtures were assessed qualitatively for setting and hydrolytic stability and the compressive strength of some of the hardened cements was measured. The results are discussed in terms of the atomic structures of the minerals and polyacids employed.
Hardened alite pastes of various porosities. I. Degree of hydration, compressive strength and total porosity
Authors: Abo‐El‐Enein Salah A. , Goto Seishi , Kondo Renichi , Mikhail Raouf Sh.
Published: July 2010

The alite used in this investigation was synthesised from the stoichiometric mixture at 1550°C. The hardened alite pastes were made using initial water/alite ratios of 0.20, 0.30, 0.45 and 0.60. Degree of hydration, compressive strength and total porosity were estimated at various hydration time intervals of 0.5 h, 2 h, 6 h, 1 day, 3 days, 7 days and 28 days. A meaningful relation between compressive strength and water/alite ratio was established at constant values of degree of hydration, total porosity and Powers' gel‐space ratio.
A new method for the purification of Egyptian cotton waste fibres
Authors: Abou‐State M. Amine , Awad Boshra M. , El‐Megeid Fouad F. Abd
Published: July 2010

A new pulping method using sodium nitrate was successfully used for the purification of Egyptian cotton waste fibres. Sodium nitrate alone, sodium nitrate in nitric acid solution and sodium nitrate in sodium hydroxide solution were used in pulping. The chemical, physical and sub‐microscopic characteristics of the pulps obtained and their reactivity towards xanthation were estimated. The best results were obtained when a mixture of sodium nitrate and nitric acid were used in pulping.
Convenient synthesis of perhydroindene derivatives from 2,7‐dimethyl‐1,3,7‐octatriene
Authors: Watanabe Shoji , Suga Kyoichi , Tsuruta Haruki , Sato Toshiya
Published: July 2010

Several perhydroindene derivatives were prepared from 2,7‐dimethyl‐1,3,7‐octatriene (I) via Diels Alder reaction followed by cyclisation. For example, the Diels Alder reaction between I and methyl vinyl ketone (II) in the presence of Lewis acid afforded 4‐acetyl‐3‐(3‐methylbut‐3‐enyl)‐1‐methylcyclohexene (IIIa), which, upon treatment with phosphoric acid, was converted to a mixture of 2‐acetyl‐5,7,7‐trimethyl‐bicyclo [4,3,0]‐non‐1‐(6)‐ene (IV), 2‐acetyl‐5,7,7‐trimethylbicyclo[4,3,0]‐non‐1‐ene (VI) and 2‐isopropyl‐3,6‐dimethylindene (V).
Mechanism of light fading of dyes on cellophane and poly(ethylene terephthalate)
Authors: Shah Champaklal D. , Srinivasan Rajagopalan
Published: July 2010

Studies of relative rates of fading of dyes and Hammett σ‐value of substituents in their molecules lead to further evidence that fading of azo dyes on Cellophane and poly‐(ethylene terephthalate) is probably an oxidation type of reaction. Absorption spectra of the same dye on these two substrates tend to indicate a very high state of aggregation of dyes on Cellophane as compared to that on poly(ethylene terephthalate).
Homogeneous and two phase sulphonation of some aromatic hydrocarbons
Authors: Sohrabi Morteza , Kaghazchi Tahereh , Hanson Carl
Published: July 2010

The two phase sulphonation of benzene, toluene and p‐xylene with concentrated sulphuric acid has been studied in a one litre batch reactor. The kinetic rate constants as a function of sulphuric acid concentration and the overall mass transfer coefficient times the interfacial area per unit volume of the acid phase as a function of agitation speed have been determined. The rates of sulphonation of toluene and p‐xylene relative to that of benzene in the range 15.5–17 mol/litre sulphuric acid have been found to be 64 and 280 respectively. Finally, it has been shown that in aromatic sulphonation no linear relationship exists between the logarithms of the partial rate factors and the relative cation localisation energies. This is in contrast to the behaviour of some other electrophilic aromatic substitution such as halogenation, but is similar to aromatic nitration.
Use of Hildebrand and Lamoreaux's theory to predict solubility and related properties of gas‐liquid systems
Authors: Linford Roger G. , Thornhill David G. T.
Published: July 2010

There is a need in many fields such as chemical engineering, process chemistry and pharmacology for reliable data on the solubility, entropy of solution and partial molar volume of gases in liquids. Experimental data are not available for many systems of practical and academic importance and consequently a reliable theory to predict values for these properties would be of great use. Recent refinements of solubility parameter theory have been successful in predicting such values for several systems and in this paper results obtained from this theory are compared with experimental measurements on a large range of gas‐liquid systems. The agreement found is satisfactory in the most part, but for helium, neon, xenon, hydrogen and deuterium, the predicted results deviate consistently from the experimental values. This is to be expected on the basis of some of the earlier results of solubility parameter theory and an empirical modification is proposed that yields significant improvements in the predicted values. This has also been used to predict values for carbon dioxide, tetrafluoromethane and sulphur hexafluoride to which the theory is not directly applicable. Values predicted by solubility parameter theory are compared with those obtained by Battino and co‐workers from scaled particle theory. In general, the two theories are equally successful in predicting solubilities, but refined solubility parameter theory yields better values of entropy of solution. It is concluded that the theory provides a useful means of predicting solubility and entropy of solution but that prediction of partial molar volume results is limited because of the paucity of data for the thermal pressure coefficients of the solvents. Attention is drawn to apparent inaccuracies in certain experimental measurements. The interrelationship between the various forms of the entropy of solution used by different workers is clarified. A value of the energy of vaporisation of carbon dioxide, δE2v=2.64±0.15 kcal/mol is calculated.
Preparation of pyridinemonocarboxylic acids by catalytic vapour phase oxidation of alkylpyridines. II. Oxidation of 2‐methyl‐5‐ethylpyridine to niacin
Authors: Järås Sven
Published: July 2010

The vapour phase air oxidation of 2‐methyl‐5‐ethylpyridine (MEP) has been investigated, and the various oxidation products identified. Using a doubly promoted vanadium catalyst, V2O5–TiO2–K2O, a 98% (mole) conversion of MEP was obtained with a yield of 36% for niacin and 18% for recirculatable products (i.e. products with an intact 3‐picoline skeleton) at a temperature of 413°C and a space velocity of 5500 h−1. In a comparison of the singly promoted catalysts, varying the atom ratio V/Ti, the catalyst with V/Ti = 100/25 was found to be most active. In a comparison of different preparation temperatures for the same catalyst, 1250°C was found to be most satisfactory. A reaction scheme is proposed with the corresponding rate constants and apparent activation energies.
Determination of specific surface area of ferric oxide and alumina powders
Authors: Rahman Muhammad A. , Ghosh Ashim K.
Published: July 2010

Methods for measuring the surface areas of powdered solids are considered and the specific surface areas of ferric oxide and alumina powders using adsorption of stearic acid from benzene solution are determined. It has been found that the value of the specific surface area of both powders agree with the BET nitrogen gas adsorption area if it is considered that the area occupied per molecule of stearic acid on the powder surface is of the order of 60–70Å2. This finding shows that orientation of the stearic acid molecule on the solid/liquid interface takes place so that stearic acid molecules lie neither completely perpendicular nor completely parallel to the surface. Possible orientations of stearic acid chains on the surface are envisaged.
Synthesis and photochemical stability of 1‐phenylazo‐2‐naphthol dyes containing insulated singlet oxygen quenching groups
Authors: Griffiths John , Hawkins Christopher
Published: July 2010

Although 1‐arylazo‐2‐naphthols undergo direct and sensitised photochemical fading in solution by a singlet oxygen mechanism, the introduction of singlet oxygen‐quenching substituents (N,N‐dialkylaminomethyl‐) affords no protection against fading, and in many cases accelerates photodegradation. This has been attributed to the high reactivity of the dialkylaminomethyl‐groups towards hydrogen abstraction, thus rendering free radical modes of decomposition more favourable. In the presence of peroxide‐radical scavengers the latter reactions are suppressed, and the dialkylaminomethyl‐groups then show a protecting effect against fading by singlet oxygen.
The H2ONaCl–sucrose phase diagram and applications in cryobiology
Authors: Gayle Frank W. , Cocks Franklin H. , Shepard Marion L.
Published: July 2010

The liquidus surface of the primary ice phase field of the H2ONaCl–sucrose ternary system has been determined by differential thermal analysis (d.t.a.) techniques. Except in the region of high sucrose concentrations, the line of two‐fold saturation bounding this field also was determined. Non‐equilibrium glassy phases were formed throughout the system. The degree of metastability of these phases increases with sucrose concentration. At high sucrose levels, the metastability was such that detection of the line of two‐fold saturation was precluded. In general, it was found that sucrose was less effective on a weight percent basis than dimethyl sulphoxide and glycerol in depressing the melting point of primary ice and, consequently, less effective in suppressing salt concentration effects at low temperatures in the liquid phase which is residual to primary ice formation.
A novel method for the hydrolysis of ethyl and isopropyl silicates
Authors: Emblem Harold G. , Walters Ian R.
Published: July 2010

The hydrolysis of ethyl and isopropyl silicates without the use of an acid or base catalyst is described. The silicate and an alcohol which is a mutual solvent for water and the silicate are treated with water, preferably under reflux. For ethyl silicate the reaction temperature can be as low as 40°C. A liquid hydrolysate is obtained when the rate of water addition is carefully controlled. This hydrolysate will form a rigid coherent gel capable of binding refractory materials. Liquid hydrolysates prepared in this way have been used to make refractory shapes, also foundry moulds and cores for precision piece moulding work and an ethyl silicate hydrolysate can be used to prepare an anti‐corrosion paint based on zinc. It would be expected that other lower alkyl silicates can be treated similarly to form hydrolysates which give a rigid coherent gel capable of binding refractory materials and which can also be used to prepare anti‐corrosion paints based on zinc.
The prediction of the ternary liquid‐liquid equilibrium by means of the NRTL‐equation
Authors: De Fré Raphaël M. , Verhoeye Lucien A.
Published: July 2010

The prediction of ternary liquid‐liquid equilibria by means of the NRTL‐equation and using the parameters obtained by the correlation of the limiting binary systems is examined. The predicted data are compared with experimental data for systems composed of an aromatic and an aliphatic hydrocarbon and sulpholane. The number of sets of binary parameters obtained from the correlation of the binary systems is infinite. For any value of the non‐randomness parameter a corresponding pair of energy parameters can be determined, giving rise to a set fitting the data equally well. Limits to the value of the parameters can only vaguely be determined on the basis of their physical meaning. The upper limit of the non‐randomness parameter related to the heterogeneous binary system is more precisely defined. Some general conclusions for the selection of the parameters could be reached. The predicted heterogeneous area is in general too large but decreases with increasing values of the non‐randomness parameter of the heterogeneous binary system. The value of the parameters of the homogeneous binary system has only a small influence on the position of the binodal. The slope of the tie lines is mainly determined by the non‐ideality of the homogeneous binary systems.
Industrial brine production using power station waste heat to assist solar evaporation of sea water
Authors: Fellows S. Kevin , Rothbaum H. Peter
Published: July 2010

The rate of evaporation from a slightly heated pond of sea water, over and above the rate from an unheated control pond, has been found to be about 5.6 m of depth per year, for each kW/m2 of heat density applied. In winter about 40%, and in summer about 55%, of the added heat goes to increasing evaporation. In conjunction with local data on rainfall and natural evaporation, this value can be used to predict the net evaporation from a heated pond at a chosen site. If a power station in the Auckland area had sea water cooling ponds of the usual size, the combination of natural evaporation, rainfall, and evaporation due to heating would result in a net evaporation of 1.02 m per year and production of a concentrated brine containing at least 200 000 tonnes per year of salt, for a 1400 MWe power station. The degree of concentration allowed in the cooling pond is limited by the formation of scale in the condensers. By adding trisodium phosphate (obtainable cheaply in New Zealand from a low quality phosphate ore) and ammonium chloride to the brine, the scale‐forming calcium and magnesium can be precipitated as a mixture of metal phosphates and metal ammonium phosphates. The precipitate has potential value as a high‐analysis fertiliser or a cattle feed supplement. At the same time a non‐scaling brine is produced, which can safely be concentrated five‐fold in a power station cooling pond. The brine is then suitable as feed for a caustic/chlorine electrolysis plant. A portion of the caustic soda product must be recycled to the preparation of the trisodium phosphate.
Enzyme technology and molecular biology
Authors: Thomas Daniel , Gellf Gérard
Published: July 2010

Enzyme technology could lead to a completely new type of chemical industry utilising moderate conditions of pH, temperature and pressure to produce from wastes or by‐products, high yields of complex chemicals without generating new waste products that pollute the environment. The potential of enzyme technology is great and applications are foreseen in industry, chemical analysis and in medicine. The new tools of this branch are immobilised enzymes or whole cells with enzymatic capacity. Methods of modern biochemistry must be applied, including genetic manipulation, molecular aging and protein chemistry.
Global aspects of biotechnology
Authors: Hedén Carl‐Göran
Published: July 2010

The attention given by the media to the turbulence caused by the current moves towards political independence often obscures the fact that a range of major problems, as well as powerful economic and technical forces, point towards increased levels of interdependence. Those two trends breed contradictions that inspire debates which actually give little room for considering the long‐range impact of science and technology. This is quite a serious matter, since the developments in some areas, like microelectronics and bioengineering, will obviously have such far‐reaching effects. Both rich and poor countries realise that such dynamic areas will sharpen the competitive edges between nations, but their potential for solving some common problems tends to be pushed into the background. In an effort to compensate for this tendency not only EEC through FAST, but also UNIDO has, however, recently initiated a series of reviews of the implications that various emerging breakthroughs will have on the economic growth and life‐styles both in developed and in developing countries. A few points that have emerged from the microbiology study and particularly the significance of biotechnology at the interphase between communications and settlement planning are highlighted.
The present state of fermentation reactors
Authors: Sittig W.
Published: July 2010

The actual application of fermenters other than stirred tanks in industry is scarce. Only minor changes have been performed in stirred‐tank design. Due to the increase of energy costs even the trend to higher power‐input rates has been stopped. Progress has been high as far as automatic analysis and control are concerned. For single‐cell protein plants bubble column and air‐lift loop systems have been improved. Surface aeration has regained interest because its energy cost can be kept considerably lower than with submerged systems. In the meantime the experience gathered with deep‐tank fermentation has begun to exert influence even on sewage treatment plants. A number of examples demonstrate that better economy has been achieved when flat basins are replaced by reactors of considerable depth.
Mathematical models and the design of biochemical reactors
Authors: Roels Joop A.
Published: July 2010

The application of so‐called macroscopic methods, that is a widely accepted tool in chemical as well as in biochemical engineering, rests on the possibility to construct a balance equation for the rate of change of the amount of an extensive quantity present in the system. In such a balance equation two types of contribution appear, one due to exchange of matter or energy with the environment and the other due to conversion in the system. A special class of quantities, i.e. the amounts of the chemical elements and energy, are not subject to net conversion in the system. These are termed conserved quantities. This observation leads to useful approaches towards the analysis of the stoicheiometry of aerobic and anaerobic growth and the calculation of heat production. For the kinetic description of the behaviour of systems a reduction of the complexity inherent to reality is a necessary prerequisite to obtain a workable model. The comparison of the relaxation times of the internal mechanisms of the system and those of changes in its environment is shown to be a powerful tool in the reduction of model complexity. An unstructured model, based on a very simplified picture of the complexity of the biomass present in a culture, is treated and its range of validity is analysed. Finally some aspects of the description of transport phenomena inside fermentation equipment and their interaction with microbial metabolism are discussed.
Some basic principles for the layout of tower bioreactors
Authors: Schügerl Karl
Published: July 2010

Depending on the bubble‐coalescence property of the fermentation medium different aerator types should be used in tower bioreactors. When bubble coalescence is suppressed the use of concentrated gas‐dispersion at the tower bottom and for a coalescence‐promoting medium distributed gas‐dispersion along the tower are recommended. The latter can be realised in multistage towers with stage‐separating trays. The aerator efficiency depends on the structure of the turbulence which is produced by the aeration. The smaller the turbulence scale the higher the efficiency of the aerator. By using a loop the bubble‐coalescence rate is reduced and the cells are uniformly distributed along the column, but mixing time is increased and volumetric mass‐transfer is reduced.
Recovery of microbial polysaccharides
Authors: Smith Ian H. , Pace Gary W.
Published: July 2010

Microbial polysaccharides are a class of water‐soluble polymers which have grown in industrial importance over the past 20 years and present special problems of postfermentation recovery. Extracellular polysaccharides of commercial interest are considered with particular emphasis on the underlying principles and problems associated with each stage of processing.
Scale‐up of formate dehydrogenase by partition
Authors: Kroner K. H. , Schütte H. , Stach W. , Kula M.‐R.
Published: July 2010

Details of the process development and a flow diagram for the isolation of formate dehydrogenase from Candida boidinii are presented. Formate dehydrogenase was isolated from 30–50 kg of wet cells of C. boidinii to produce a technical‐grade enzyme, purity about 2–3 units mg−1 with yields of up to 75%. The preparation is suitable for NADH‐regeneration in a membrane reactor. A summary and comparison of different possible routes for the isolation and purification are given and analysed with regard to process time and volumes handled. It is shown, that the time required is much smaller and the resulting productivity is much higher, when aqueous two‐phase systems are fully utilised in the process.
Soluble temporarily immobilised biocatalysts
Authors: Hahn‐Hägerdal Bärbel , Mattiasson Bo , Andersson Elis , Albertsson Per Åke
Published: July 2010

High catalytic density, good catalytic stability, simple catalyst recovery and facilitated product up‐grading are necessary requirements for the industrial application of biocatalysts such as enzymes and cells. These requirements can be met by using soluble immobilised biocatalysts. The biocatalysts are usually confined in space to one of two aqueous phases, both of which have high water content and therefore are biocompatible and non‐toxic to biological material. The products are either evenly distributed among the phases or partitioned to one of the phases. Soluble immobilised biocatalysts are particularly useful for bioconversions of particulate or macromolecular substrates, as well as for bioconversions involving product inhibition. The feasibility of soluble immobilised biocatalysts has been studied on the enzymic saccharification of cellulose, glucose fermentation with Saccharomyces cerevisiae and the bioconversion of cellulose into ethanol.
Protein recovery from dairy industry wastes with aerobic biofiltration
Authors: Wheatley Andrew D. , Mitra Ruth I. , Hawkes Herbert A.
Published: July 2010

Experiments were carried out to improve the economics of effluent treatment by the recovery of single cell protein. Field observations showed that acidic strong wastes, such as those from the dairy industry, produced a predominantly fungal biomass. Mixtures of dairy waste and domestic sewage did not produce fungal films. The most common fungi isolated were Fusarium and Geotrichum, but the species was affected by local conditions, i.e. creamery, yoghurt, milk or cheese wastes and the load to the plant. Batch culture was used to determine the growth requirements of Fusarium and Geotrichum and continuous culture, on vertical and horizontal fixed films, to determine growth and sloughing at different organic loads. The fungi grew well on acidic strong wastes which would discourage other organisms. A 1 m3 h−1 pilot plant was built to treat the wastes from cheese, butter and cream production. The plant was run at pH 4–5 and at between 5 and 10 kg of BOD day−1 m−3. BOD removal was between 30 and 50% and biomass production between 0.1 and 0.5 kg of dry solids day−1. The filamentous fungal growth was separated from the tower effluent by an inclined screen. The amino acid content of the product was similar to other single‐cell protein. Feeding trials are being carried out.
Food preservation: An example of the application of negative biotechnology
Authors: Jarvis B. , Paulus K.
Published: July 2010

The processing of foods to ensure the availability for the consumer of a wide variety of safe stable products provides a good example of the application of ‘negative biotechnology’. The objectives are to optimise the use of food resources by reduction or elimination of spoilage and waste, control food‐borne health problems and develop ‘new’ food products. Our work describes the way in which technology is applied to control of biological, chemical and physical changes in foods. Examples are given to illustrate the implications for product shelf‐life of the various process operations including inter alia, thermal and irradiation treatments, restriction of available water, use of chemical preservatives and the choice of packaging systems. Special emphasis is placed on the need to optimise quality and safety by the proper application of kinetic data for the various process operations. The concepts of quality assurance, ‘in‐line’ process control and the use of microprocessor technology in the control of critical processes is considered. The work concludes with a look at the future requirements of the food processing industry in relation to developments in ‘negative’ biotechnology.