bluuebunny/crossref_metadata_2025_split huggingface dataset:
The feasibility of a new method for maintaining clean conditions in once‐through boilers
Authors: Turner D. J. 
Published: July 2010

AbstractA method of using chelating agents for maintaining clean conditions in once‐through boilers is considered in detail. It involves forming volatile, inner complexes with unwanted oxide material so that the metal ions can be carried through the turbine and, after condensation of the steam, be removed by ion exchange. Potentially suitable agents are considered from the point of view of thermal stability and corrosion risk; also thermodynamic stability and volatility of their complexes. Most chelating agents available in commercial quantity appear to be unsuitable but oxine (8‐hydroxy quinoline) at least, seems satisfactory and worth investigating further. Oxine, along with certain other aromatic chelating agents, should be able to prevent the formation of metal‐oxide debris in high pressure drum boilers.
Thermodynamics of interaction of acetylene with cuprous ion in an aqueous medium
Authors: Natarajan G. S. , Venkatachalam K. A. 
Published: July 2010

AbstractThermodynamic data for formation of Cu.C2H2+ and Cu+.C2H‐ complexes in aqueous CuCl‐NH,Cl‐HCl medium have been obtained by the potentiometric technique. The data are of interest in homogeneous liquid phase catalytic conversion of acetylene to various products.
A study of some intermolecular interactions between organic dye molecules in aqueous solution by fluorescence quenching and difference absorption spectrophotoinetry
Authors: Owen E. D. , Sultana Q. 
Published: July 2010

AbstractIntermolecular interactions between the fluorescent organic dyes Fluorescein, Fluorescein Diiodide, Eosin, Rose Bengal, Erythrosin, Phloxine, Phloxine B, Rhodamine 6G, Lissamine Rhodamine B200 and the non fluorescent Crystal Violet and Malachite Green in aqueous solution have been studied by fluorescence quenching and difference absorption spectrophotometry. Equilibrium constants for the interactions have been determined by the two techniques mentioned and are compared. Absorption and fluorescence spectra and rates of photolysis of solutions obtained by extracting aqueous solutions of the mixed dyes into organic solvents are described.
Dielectric and thermodynamic behaviour of some monohydric alcohols in dioxane and cyclohexane
Authors: Sakellaridis P. , Hinopoulos B. 
Published: July 2010

AbstractThe dielectric and thermodynamic behaviour of some monohydric alcohols in their dioxane or cyclohexane solutions is investigated in the microwave frequency region as a function of concentration and temperature.It has been found that the relaxation time decreases monotonically on the addition of dioxane. This behaviour is different from that found previously by similar measurements on alcohol‐heptane solutions and in the present investigation on ethanokyclohexane solutions. The results are discussed in relation to the chemical structure.Computation of the experimental data by a polynomial curve fitting programme has resulted in analytical relationships between the relaxation time variation and the concentration.
The effect of heat treatments on the semiconductor properties of a commercially electrodeposited manganese dioxide
Authors: Foster I. B. , Lee J. A. , Tye F. L. 
Published: July 2010

AbstractThe temperature dependence of d.c. conductivity and thermoelectric power has been studied for a series of thermally treated samples of an electrodeposited, microcrystalline, γ‐phase MnO2. Measurements were made on samples compacted at 3.86 × 105 KN/m2. Measurements of a.c. impedance up to 50 MHz were made on the powder samples to test for particle homogeneity.The results indicated that a hopping electron transport model was probably appropriate for these samples and that the majority carriers were electrons, possibly ionised from donor sites provided by oxygen deficiency. Conductivity, surprisingly, was found to increase in an oxygen environment and it is suggested that oxygen adsorption greatly enhances the electron mobility.The d.c. conductivity and thermoelectric power were found to be strongly dependent on sample outgassing temperature. The former reached a maximum at about 320 °C, the latter became less negative with increasing outgassing temperature. It is tentatively proposed that carrier density and “surface” mobility increased as terminal OH groups forming strong traps on manganese sites were removed by thermal treatment.Measurements of a.c. impedance on samples outgassed at 35 °C and 365 °C displayed dispersion around 20 MHz indicative of a high resistance surface skin possibly due to a hydroxylated and reduced surface respectively.
Dissolving pulps from Egyptian bagasse I. Effect of depithing on the chemical, physical and sub‐microscopic characteristics of viscose pulps
Authors: Abou‐State M. Amine , Helmy Samia A. 
Published: July 2010

AbstractEgyptian bagasse was pulped by the prehydrolysis‐sulphate process. The effects of depithing on certain chemical, physical and sub‐microscopic characteristics of the pulp, in particular its reactivity towards xanthation, were investigated. Depithing before and after prehydrolysis was compared. Pulps with a higher degree of chemical purity and higher degree of whiteness showed better reactivity towards xanthation. However, the most important factor affecting the reactivity was the accessibility of the cellulose hydroxyls to reactant molecules.
The extraction of divalent cobalt, copper, zinc and cadmium from hydrochloric acid solutions by tri‐n‐butyl phosphate
Authors: Sato Taichi 
Published: July 2010

AbstractThe partition of divalent cobalt, copper, zinc and cadmium between hydrochloric acid solutions and solutions of tri‐n‐butyl phosphate (TBP) in benzene or kerosene has been investigated under different conditions. Further the absorption spectra of both the aqueous and organic phases have been studied, and the infrared spectra of the organic phases have been examined. It was found that the order of the extraction efficiency of TBP for divalent metalsis Zu > Cd > Cu > Co for [HCl]aq < 8M and Zn > Cd > Co > Cu for [HCl]aq > 8M.
Autocatalysis in calcination of powdered lead
Authors: Miyazaki K. 
Published: July 2010

AbstractThe kinetics of calcination of powdered lead has been studied. The oxidation of powdered lead, a non‐stoichiometric suboxide of lead, appears to be autocatalytic at an elevated temperature of 400 to 520 °C, and the end product is red lead Pb3O4. Blending powdered lead with a small amount of red lead greatly increases the rate of calcination to yield the final product Pb3O4, compared with the case of calcination of powdered lead alone.
Precipitate flotation in the treatment of metal‐bearing effluents
Authors: Pearson Douglas , Shirley Joseph M. 
Published: July 2010

AbstractFlotation is proposed as an alternative to sedimentation for removing metal hydroxide precipitates formed in the treatment of effluents from metal finishing operations. A brief study has shown the effect of different parameters in the system on the metal content of the effluents. An estimate of the costs of treating effluents by this method showed it to be more costly than sedimentation; on the other hand, metals recovery may be facilitated and this would offset the higher costs.
Some applications of rapid gas chromatography
Authors: Cross Robert A. , Robinson Stuart C. F. 
Published: July 2010

AbstractA gas chromatograph has been developed with which simple gas mixtures can be analysed rapidly, repetitive separations being possible every few seconds. The instrument operates automatically, sampling from a number of points, and it can be remotely controlled.Changes taking place in the composition of atmospheres, flue gases and engine exhausts, which were too rapid for estimation by conventional sampling and analytical procedures, were followed without difficulty, and the results of these analyses are presented and discussed.
pH and Eh control of cultures of sulphate‐reducing bacteria
Authors: Brown Donald E. , Groves George R. , Miller John D. A. 
Published: July 2010

AbstractBatch cultures of Desulfovibrio vulgaris, carried out in a 5‐litre stirred fermenter, are described. Bacterial counts and sulphide formation are reported for experiments carried out under a selection of controlled Eh and pH conditions. Specific growth and sulphide formation rates are determined and compared. Variations in the growth rates under the different controlled conditions are examined and discussed in terms of product inhibition by sulphide. A relatively high specific rate of exponential growth was observed at Eh = ‐ 150 mV and pH=6.95, when sulphide inhibition was believed to be at a minimum.
Production of an amylolytic enzyme by Bacillus polymyxa in batch cultures
Authors: Griffin Patrick J. , Fogarty William M. 
Published: July 2010

AbstractGrowth of Bacillus polymyxa and high activities of amylase were obtained in media containing starch and peptone. Of the metals of biological significance, calcium and manganese had the most beneficial effects on enzyme yields. Control of pH was critical for the establishment of conditions which yielded maximum levels of enzyme. The appearance of highest amylase activity in culture supernatant liquors during the stationary phase of growth was not due to autolysis; intracellular levels of the enzyme were shown to be very low throughout the fermentation. When the organism was grown in a medium containing a low level of starch (1%, w/v), amylase activity was low during the logarithmic phase of growth but rose rapidly in the culture liquor when growth ceased. Negligible activity was detected when the organism was grown in a medium which contained excess starch. This amylase therefore appears to be a true extracellular enzyme, in the accepted sense. It is produced in response to exhaustion of the carbon source from the medium.
Separation of U(vi) from carbonate solutions by ion flotation
Authors: Shakir Kamal 
Published: July 2010

AbstractThe ability of uranyl ions to form highly charged anionic complexes with carbonate or bicarbonate anions furnishes the basis of its removal from carbonate media by cationic collectors using the ion flotation technique. In this investigation cetyl trimethyl ammonium bromide was used as collector. The extent of removal depends on many factors and removals approaching 100% could be achieved under certain controlled conditions. The factors that can affect the flotation process, viz. gas flow rate and concentrations of collector, uranium and carbonate were investigated and the best conditions were selected.
The anomalous behaviour of isoquinoline relative to quinoline and its significance in relation to structure and reactivity
Authors: Roy Sisir K. , Roy Subhash C. , Rao H. S. 
Published: July 2010

AbstractVapour phase catalytic oxidation of quinoline over a vanadia base catalyst yielded nicotinic acid, while vapour phase catalytic ammoxidation gave 3‐cyano‐pyridine, the benzenoid ring undergoing cleavage in both cases. The isomeric molecule, isoquinoline, was however found to behave in sharp contrast, undergoing an unexpected reaction in its transformation into phthalimide during identical conditions of oxidation and into ortho‐phthalonitrile during ammoxidation, the pyridine ring undergoing cleavage in both cases, with the appearance of the heterocyclic ring nitrogen in a reactive functional group. The significance of these observations is discussed in relation to structure and reactivity and possible reaction mechanisms are suggested.
The thermal decomposition of pure and doped cadium carbonate: I. Kinetics
Authors: Mikhail R. Sh. , Dollimore David , Kamel A. M. , El‐Nazer N. R. 
Published: July 2010

AbstractThe thermal decomposition of both pure and doped cadmium carbonate has been studied. Doping was effected by adding 1, 5 and 10 atom‐% of Al3+, Li+, Zn2+, Ca2+, and Ba2+. Differential thermal analysis, as well as the kinetics of isothermal decomposition of the various carbonates, has been investigated between 310 and 560 °C. The decomposition of both the pure and doped samples was found to obey Mampel's theory. Rate constants were evaluated and found to be appreciably affected by the presence of foreign ions. Application of the Arrhenius equation gave an activation energy of 22.5 kcal/mol for pure cadmium carbonate which is comparable with the standard enthalpy of the reaction which is 22.0 kcal/mol. On the other hand, in applying the Arrhenius equation to the rate constant of the doped samples, no straight lines could be obtained indicating a continuous decrease in the activation energy with a rise of temperature. The activation energies were found to vary between 4.0 and 44.0 kcal/mol. Discussion is presented to account for the effect of the various dopes on the mechanism of thermal decomposition.
Dissolving pulps from Egyptian bagasse. II. Low temperature cooking
Authors: Amine abou‐state M. , Awad Boshra M. , El‐Morsy M. Mossad 
Published: July 2010

AbstractBagasse was pulped by the prehydrolysis‐soda process. Increasing the concentration during prehydrolysis or pulping had a favourable effect on pulp properties. Further improvement in these properties was attained when the increase in concentration was accompanied by lowering the temperature. The effects of increasing the concentration and lowering the temperature of prehydrolysis and pulping were compared.
High purity cyclohexane from petroleum streams by extractive distillation
Authors: Tripathi Raghunath P. , Sagar Jatinder M. , Gulati Indar B. 
Published: July 2010

AbstractIn view of the high cyclohexane content (1.81 wt‐%) of one of the Indian crude oils, a systematic study on the production of high purity cyclohexane from a suitable refinery stream was undertaken at the Indian Institute of Petroleum. Superfractionation of the refinery stream followed by extractive distillation of the resulting concentrate, with aniline as solvent, gave cyclohexane product of 99.0% purity in a continuous bench scale operation. The solvent free extract does not need any refractionation step for producing cyclohexane of the above purity.
Polymerisation of bicyclohepta‐(2,5)‐diene with palladium‐π‐complexes
Authors: Hojabri Fereidun 
Published: July 2010

AbstractA pinene‐π‐allylic complex of palladium was capable of catalysing the polymerisation of bicyclohepta‐(2,5)‐diene. Polymerisation pattern was the same as in the case of PdCl2, i.e. only one double bond of the diene was opened by this reaction. The optimum temperature range for the polymerisation was between 130 and 200 °C. Polar solvents retarded the reaction.The Pd‐π‐allylic complex, for the polymerisation of the same olefin, was a more active catalyst than other palladium compounds (e.g. PdCl2).
Flotation of phosphorus(V), molybdenum(VI), and rhenium(VII) oxyanions
Authors: Charewicz Witold 
Published: July 2010

AbstractEfficiency and intensity of the flotation of isostructural, tetrahedral oxyanions with the cationic (R)4N+ type surfactant were examined, exemplified by the case of the diluted aqueous solutions of phosphorus(v), molybdenum(vi) and rhenium(vii) at concent rations of 1 × 10−4, 5 × 10−5 and 1 × 10−5 kmol m−3. No direct relation was found between the flotation efficiency and the charge and size of the examined ions. For ions of equal charge, the Grieves entropy criterion15 was obeyed in most cases.
Pulp and paper from corn stalks, II
Authors: Abou‐State M. Amine , El‐Masry Ahmed M. 
Published: July 2010

AbstractPulps with the same chemical characteristics were prepared by carrying out the pulping process either under atmospheric pressure or under high pressure. Atmospheric pressure pulping had a highly favourable effect on the strength properties of paper in contrast to high pressure pulping. The effects of the pith fraction, the stems and the leaves on the chemical composition and the physical strength characteristics were investigated.
The vapour‐liquid equilibrium of ternary systems with limited miscibility at atmospheric pressure
Authors: Van Zandijcke F. , Verhoeye L. 
Published: July 2010

AbstractThe complete study of the vapour‐liquid equilibrium of ternary systems with limited miscibility requires vapour‐liquid equilibrium determinations and liquid‐liquid equilibrium determinations at boiling point. The vapour‐liquid equilibrium was determined by means of an equilibrium still based on the principle of Giilespie but modified in such a way that an accurate boiling point measurement, even for systems with heterogeneous liquid was possible and that the vapour phase was analysed without previous condensation. Two ternary systems have been studied: the system methanol‐ethylacetate‐water and the system ethanol‐ethylacetate‐water. The ternary data have been predicted by means of the equation of Renon and Prausnitz. The parameters are determined by correlating the binary data. The ternary vapour‐liquid equilibrium are predicted within 1‐2. 10 −2 mol fraction for the vapour composition and 1°C for the boiling point. The position of the predicted tielines of the liquid‐liquid equilibrium at boiling point was almost coinciding with the position of the experimental tielines. There was a slight deviation of the predicted and experimental binodal.
Organophosphoryl ethanolamine analogues II. Synthesis of methyl‐N,N‐dipropyl and piperidyl phosphonamidic acid esters
Authors: El‐Deek M. , El‐Yazid A. Abou 
Published: July 2010

AbstractA series of phosphonamidic acid esters, containing ethanolamine analogue moieties, P‐O‐CH2CH2NRR1, have been synthesised, as potential anticholinesterases. The infra‐red spectral data confirm the chemical structure of the prepared compounds.
Kinetics of hydrogen chemisorption on supported molybdenum disulphide
Authors: Samuel P. , Yeddanapalli L. M. 
Published: July 2010

AbstractChemisorption of H2 on MoS2‐Al2O3 catalyst was studied at different temperatures and initial pressures. The results when analysed according to the Elovich equation revealed multiple kinetic stages. Assigning two sets of boundary conditions to the equation, a statistical procedure employing least square analysis has been applied for the evaluation of the Elovich parameters a and α and their temperature dependence has also been followed. A comparison is made with the parameters derived by the graphical method. The role of initial surface saturation q0 on the sequence of the multiple kinetic stages is discussed. Excepting for descriptive purposes, the kinetic stage connotation is not strictly followed. On the other hand, all the first straight line portions of the Elovich plots for a given initial pressure including the single stage plots have been grouped together and the corresponding a and α were calculated. The merits of deriving the apparent activation energies from the initial rates rather than from α are discussed.
Effect of various steps of purification on ash content and ash constitution of cellulose. I. Cellulose prepared from cotton linters
Authors: Shahine Salah , El‐Shorbani Salah , El‐Sadani Mohamed 
Published: July 2010

AbstractThe effect of the various steps of purification on the ash content and ash constitution of cellulose prepared from cotton linters has been examined. After each step of purification, samples were analysed for total ash, SiO2, Ca, Mg, Fe, Al, Cu and Mn. Two methods of bleaching were investigated. The first involves double treatment of cellulose with sodium hypochlorite solution, and the second one treatment with hypochlorite followed by another treatment with sodium chlorite solution. The second method has a better effect in diminishing the ash content.
Reaction kinetics and mass transfer in glucose isomerisation with collagen‐immobilised whole microbial cells
Authors: Saini Rakesh , Vieth Wolf R. 
Published: July 2010

AbstractStable and active derivatives of collagen‐immobilised whole microbial cells containing glucose isomerase have been successfully prepared. The degree of crosslinking, swelling behaviour, and hydrophile/hydrophobe ratio of the complex was examined, since these factors could have a strong influence on the diffusional characteristics of the membrane. The studies on efficiency of glutaraldehyde tanning and its effect on the activity of the immobilised cells provided the connecting link between the network properties and the mass transfer effects. The catalytic pathway for the reversible enzymatic conversion of glucose to fructose has been elucidated by developing a kinetic model capable of describing the observed data over the entire range of substrate concentrations. In arriving at this model, we have also found that the bulk phase mass transfer limitations are negligible. Regarding the internal transport resistance, it has been determined that the effectiveness factor is between 0.95 and 1. A reactor design equation incorporating activity, packing density, and contact efficiency correction factors has been developed. Based on this equation, computer simulations of continuous reactor operation were performed to generate concentration–space time profiles. The model was verified experimentally and a close agreement between the predicted and observed values corroborated the correctness of the proposed bioreaction mechanism, the rate expression, and the design equation. The kinetics of a competing side reaction were found to be too slow to influence significantly the overall results.
A simple method for the estimation of purine and pyrimidine bases in n‐alkane grown yeasts
Authors: Erskine Richard L. , Steedman Thoma S. A. 
Published: July 2010

AbstractA method is described for the estimation of purine and pyrimidine bases on n‐alkane yeasts which employs a simple hydrolysis step with hot 72% perchloric acid followed by separation of the bases by ion‐exchange chromatography. The level of RNA in a sample can be calculated from the amounts of the bases present. The method is believed to be more precise and reliable than other methods employing extraction and u.v. spectrophotometric measurements.
Reactions of acetylene and ammonia in a continuous‐flow microwave discharge reactor
Authors: Brooks Brian W. , Spearot Rebecca M. 
Published: July 2010

AbstractBoth pure acetylene and mixtures of acetylene and ammonia have been passed continuously through a microwave discharge reactor. The reaction products from the gas mixtures were hydrogen cyanide, hydrogen and nitrogen. When the input reactant ratio (ammonia to acetylene) was below a critical value, the extent of reaction was negligible. When the critical ratio was exceeded, high conversions were obtained. When reaction did occur, the conversions of both reactants were linear functions of the power absorption in the discharge. The conversion of acetylene to hydrogen cyanide varied linearly with the input volumetric flow rate. Comparison of the present work with previous studies shows that hydrogen cyanide is not produced exclusively by the route

when mixtures of benzene and ammonia react in a microwave discharge.
Arylmercury compounds. III. Poly(arylmercury) compounds via symmetrisation reaction
Authors: Halpern Yuval , Garti Nissim 
Published: July 2010

AbstractDimercurated aryl compounds [Ar(HgX)2] are converted either to linear or cyclic poly(arylmercury) compounds. The reaction is carried out in a mixture of water and organic solvent via the symmetrisation process in which ethylene‐diaminetetraacetic acid (EDTA) and ammonia serve as chelating agent and auxiliary ligand, respectively. Similarly, mercury‐crosslinked polystyrene is obtained by applying the process for polymercurated polystyrene.