bluuebunny/crossref_metadata_2025_split huggingface dataset:
Oxidation of anthracene to anthraquinone in liquid‐phase with an air/oxygen/nitric acid system
Authors: Das Chandra Kumar , Das Nikhilendu Sekhar 
Published: July 2010

AbstractOxidation of anthracene to anthraquinone by air/oxygen in the presence of small amounts of nitric acid was studied in the liquid phase. The effects of various process variables (e.g. temperature, flow rate, amount of nitric acid and solvent substrate ratio) were investigated. An attempt was made to minimise the amount of nitric acid. The optimum conversions of anthracene into anthraquinone free from nitro compounds, using air and oxygen was found to be 81.7 and 96.2% respectively with corresponding purities of 98.5% and 99.6%.
Metabolic‐heat relation for aerobic yeast respiration and fermentation
Authors: Volesky B. , Yerushalmi L. , Luong J. H. T. 
Published: July 2010

AbstractA specially developed temperature control system on a laboratory scale fermenter enabled continuous measurement of the rate of heat production during undisturbed growth of microbial cultures. Apart from being correlated with oxygen uptake rate, the heat of fermentation was established as an additional indicator of metabolic activity. The ‘aerobic respiration’ energetic activity of Candida utilis, Candida lipolytica and Saccharomyces cerevisiae on different carbon substrates was investigated with cultures of the latter species being also studied under the ‘aerobic fermentation’ conditions induced by glucose catabolite repression.
Industrial fermentation in China
Authors: Chen T. S. 
Published: July 2010

AbstractA brief description of the recent advances in industrial fermentation in China is presented. Subject areas discussed include century‐old food products such as Soy sauce and ‘Shao Jiu’ (distilled spirits), ethanol, amino acid, citric acid, nucleic acid and enzymes. Also discussed are the recent studies on immobilised enzymes and cells and on long‐chain dicarboxylic acid fermentation.
Urea removal by anodic oxidation from saline‐simulating haemofiltrate
Authors: Köster Klaus , Wendt Hartmut , Gallus Jürgen , Krisam Gerd , Lehmann Hans‐Dieter 
Published: July 2010

AbstractUrea can be oxidised electrochemically in chlorine solution to carbon dioxide, water and nitrogen. The microkinetics of this hypochlorite‐mediated urea oxidation are elucidated. Urea destruction by hypochlorite is a relatively slow reaction and needs either high reactor volumes or a high stationary temperature to proceed with a high degree of conversion. Based on this kinetic information, the optimal working conditions and construction principles of a cheap disposable oxidation cell as well as necessary auxiliary equipment are described. Data in vitro are reported for urea removal simulating a 3 h treatment of a 60 kg kidney patient. The technical and economical possibilities for haemofiltrate regeneration are discussed.
Production and quantification of transglucosidase from Aspergillus niger
Authors: Benson Colm P. , Kelly Catherine T. , Fogarty William M. 
Published: July 2010

AbstractThe production of transglucosidase by Aspergillus niger was examined in batch culture with thin‐layer chromatography (t.l.c.). Corn steep liquor was used as the nitrogen source and the activities obtained with four different carbon sources were examined both qualitatively and quantitatively. Prompted by the non‐quantitative nature of the t.l.c. assay technique, a quantitative transglucosidase assay procedure was developed subsequently. This was based on the hydrolysis of α‐methyl‐D‐glucoside which was shown to be unaffected not only by amyloglucosidase of A. niger but also by that from a number of other organisms. The glucose released was measured by the glucose oxidase‐peroxidase reagent, thus providing a rapid and reliable quantitative assay procedure for determining transglucosidase in the presence of amyloglucosidase.
Effect of high‐temperature treatment in air on the surface area and porous texture of zirconium dioxide prepared by thermal decomposition of the nitrate
Authors: Areán Carlos Otero , Fern Ández Colinas José M. , Arjona Andrés Mata , Villa García María A. 
Published: July 2010

AbstractZirconium dioxide, prepared by thermal decomposition of zirconium nitrate, was heated in air at temperatures ranging from 573 to 1023 K. An analysis of nitrogen adsorption‐desorption isotherms on the resulting materials allowed determination of the corresponding specific surface area and porous texture. All oxides calcined within the temperature range 573–873 K were found to be basically mesoporous; the most frequent pore radius increasing from 3 to 10.5 nm as the temperature was raised. BET surface areas decreased across the same temperature range, from 94 down to 20 m2 g−1. The sample fired at 1023 K showed a BET surface area smaller than 5 m2 g−1.
Extraction of Ca(OH)2 from portland cement and 3CaO.SiO2 pastes
Authors: Ramachandran Vangipuram S. , Polomark Gary M. 
Published: July 2010

AbstractA procedure for extracting free lime from mature pastes of Portland cement and tricalcium silicate is described. It involves exposure of thin discs of paste to an aqueous solution of Ca(OH)2 in such a way that the concentration of the solution remains in the range 9.5–12 mmol CaO dm−3 throughout the extraction period. Calcium hydroxide remaining in the solid is estimated by differential scanning calorimetry and that in the extractant is estimated by atomic absorption spectrophotometry. Investigations of the extracted samples by scanning electron microscope, helium pycnometry, X‐ray diffraction, mercury porosimetry and thermogravimetry indicate that the extraction procedure has no significant influence on the C‐S‐H phase.
The selectivity of n‐heptane isomerisation on catalysts containing platinum and/or chlorine on different supports
Authors: Aodul‐Gheit Ahmed K. , Menoufy M. F. , El‐Fadly A. M. , Sif El‐Din O. I. , Sultan S. A. 
Published: July 2010

AbstractThe effect of promoting gamma‐alumina before and after calcination at 1130 K and silica‐alumina with 0.35% (w/w) Pt and/or 3.87% (w/w) Cl upon the selectivity of n‐heptane isomerisation was studied in a high pressure continuous flow reactor. Chlorination of Pt on γ‐alumina increased its catalytic activity but decreased its isomerisation selectivity, whereas chlorination of Pt on γ‐alumina calcined at 1130 K enhanced both activity and selectivity. Pt on silica‐alumina was the most active but the least selective among catalysts containing Pt plus Cl.The larger the surface area of a support, the larger the dispersion of Pt in it. Pt dispersion and distribution on the support increased markedly if impregnation was associated with chlorination. The isomerisation selectivity of a catalyst did not appear to depend on dispersion of platinum, whereas hydrocracking increased as dispersion increased.
The catalytic oxidation of organic air pollutants part 1. Single metal oxide catalysts
Authors: Heyes Christopher J. , Irwin James G. , Johnson Hilary A. , Moss Ronald L. 
Published: July 2010

AbstractSingle metal oxides, particularly Co3O4, MnO2 and CuO1 were evaluated as the basis of catalysts for the destructive oxidation of organic air pollutants, e.g. in malodorous process emissions, with special reference to their resistance to deactivation by sulphur compounds compared with Pt‐honeycomb catalysts. Tests with low odorant concentrations, 100 volumes per million (vpm) in air, demonstrated highly efficient conversion of n‐butanal or methyl mercaptan to acceptable products over the best oxides. Ability to destroy butanal in mixtures with mercaptan at the end of life‐tests, during which the mercaptan was completely removed, decreased in the order: CuO ⋍ Pt > MnO2 > V2O5 > CO3O4. Values of the odour detection threshold measured at the catalyst exit by dynamic‐dilution olfactometry were interpreted in terms of unreacted butanal and selectivity in conversion of the odorants to CO + CO2.
The catalytic oxidation of organic air pollutants part 2. Cobalt molybdate and copper chromite catalysts
Authors: Heyes Christopher J. , Irwin James G. , Johnson Hilary A. , Moss Ronald L. 
Published: July 2010

AbstractTwo mixed metal oxides, cobalt/molybdenum oxide (supported on alumina) and copper/chromium oxide, were evaluated as catalysts for the control of organic air pollutants responsible for malodorous process emissions. In laboratory tests, the ability to achieve and maintain high efficiency for the complete oxidation of n‐butanal and methyl mercaptan [100 volumes per million (vpm) in air] was determined. The life of copper chromite could be extended by washing after partial deactivation by retained sulphur. In tests with process gas using copper chromite, odour removal efficiencies (measured by olfactometry in terms of dilution to detection threshold values) at 340–415°C were mostly in the range 98.5–99.5%.
Synthesis and dyeing characteristics of some new arylazopyrazole derivatives
Authors: Fahmy Sherif Mahmoud , El‐Hosami Mamdouh , El‐Gamal Sherif , Elnagdi Mohamed Hilmy 
Published: July 2010

AbstractA variety of new arylazopyrazole derivatives were obtained by the coupling of diazotised 5‐amino‐4‐arylazopyrazoles with active methylene reagents and treatment of the resulting products with hydroxylamine hydrochloride. The behaviour of the newly synthesised products as acidic, direct and basic dyes on textiles is reported.
Kinetics of deactivation of Re2O7‐Al2O3 metathesis catalyst
Authors: El‐Sawi Mahmoud , Lannibello Antonio , Giordano Girolamo , Fedele Ubaldo , Ricca Gianfranco 
Published: July 2010

AbstractThe deactivation of 9% Re2O7‐Al2O3 catalyst during the metathesis of propene is investigated. Based on integral kinetic measurements and assuming separable deactivation kinetics, a deactivation rate equation has been developed which fits the experimental results well.
The effect of catalyst particle size on the oxidative dehydrogenation of butenes to butadiene over bismuth molybdate
Authors: Taylor Geoffrey R. , Hughes Ronald 
Published: July 2010

AbstractThe oxidative dehydrogenation of but‐1‐ene to butadiene has been investigated in a continuous flow system using a range of different particle sizes. A but‐1‐ene to oxygen ratio of 2:1 was adopted in most experiments in order to avoid over‐oxidation. The reaction rate was found to be first order in butene and zero order in oxygen in agreement with previous work. Particle size was found to have a profound influence on the rate of reaction and selectivity. The larger particle sizes operated at a temperature level above the ambient gas stream due to interphase effects. Allowance for this phenomenon enabled a revised activation energy of 41.42 kJ mol−1 to be estimated which was independent of particle diameter.
An 1H pulsed N.m.r. study of some amorphous silicate hydrates
Authors: Belton Peter S. 
Published: July 2010

AbstractAn 1H pulsed n.m.r. study of a series of amorphous sodium silicate hydrates (Na:Si= 1:1.61) is reported. Both transverse and longitudinal relaxations were examined. The transverse relaxation curves could be resolved into a Gaussian component and a component exhibiting dipolar splitting. These components were assigned to protons in hydroxyl groups and water, respectively. It was found that the hydroxyl content was independent of the total proton content. The implications of this for the structure of these solids is discussed in terms of various models.
The microbial oxidation of mixtures of methanol, phenol, acetone and isopropanol with reference to effluent purification
Authors: Wilkinson Timothy G. , Hamer Geoffrey 
Published: July 2010

AbstractThe microbial growth of a mixed culture on a simulated effluent containing methanol, phenol, acetone and isopropanol was shown to be less complex than might have been expected, with the system behaving as if it consisted of three superimposed noninteracting systems responsible for oxidation of the methanol, phenol and acetone. It was also shown that the isopropanol was cometabolised by the acetone‐utilising culture. Steady‐state data were used to predict both the minimum residence time in the reactor needed to remove the various organic components from the effluent and to predict the likely residual level of substrate in the effluent. The transient response to step changes in the operating conditions was also investigated and it was shown that the culture could respond instantaneously to defined changes with no increase in the organic concentration in the treated waste. It was shown that the culture has a higher respiratory activity compared to steady‐state respiration which gives the organism the ability to adjust quickly to changes in conditions in the reactor. These studies demonstrate that it is essential to understand biological parameters of waste water treatment processes—particularly for new treatment applications.
Litho‐ionomer cements and their technological applications
Authors: Prosser Havard J. , Wilson Alan D. 
Published: July 2010

AbstractLitho‐ionomer cements are based on the setting reaction between polymeric acid solutions and ion‐leachable materials. The setting reactions are reviewed with regard to the structure of the ion‐leachable material, the action of the polyacid and the structure of the set cement. The hydration and adhesive properties of the cements are related to the chemical structure and are important in the application of the cements as dental filling materials and splinting bandages. Other applications as a binder and cementing agent are discussed.
Stabilisation of invertases by treatment with cross‐linking reagents
Authors: Woodward Jonathan , Wiseman Alan 
Published: July 2010

AbstractCommercial baker's yeast invertase concentrate, used in the manufacture of a variety of confectionary products, was treated with various chemical cross‐linking agents in an attempt to improve its thermal stability to that of the more useful invertase from Candida utilis, which has been shown previously to have high thermal stability. Only glutaraldehyde was successful but at the expense of a loss of enzyme activity and a three‐fold increase in Km. Dimethylsuberimidate stabilised commercial invertase only slightly and the other reagents tried, either had no effect upon stability or caused a destabilisation of the enzyme. C. utilis invertase can be stabilised even further against thermal denaturation by dimethylsuberimidate. A similar stabilisation was found when this enzyme was heated in the presence of ≥ 10 mM‐CaCl2.
Synthesis of molybdenum (IV) sulphide: Part II. Reaction of molybdenum (VI) oxide with (a) zinc sulphide and (b) cadmium sulphide in the presence of ammonium chloride
Authors: Bhuiyan Nurul Haque , Ahmed Aftabuddin , Begum Sufia 
Published: July 2010

AbstractReactions of molybdenum (VI) oxide with (a) zinc sulphide and (b) cadmium sulphide were studied in the temperature range 723–973 K. Small amounts of mixtures of molybdenum (IV) sulphide and molybdenum (IV) oxide, which are difficult to separate, were produced. When ammonium chloride was added to the reactants, 89.1% pure MoS2 at 773 K and 96.17% pure MoS2 at 798 K were produced in the case of zinc sulphide and cadmium sulphide respectively.
Analysis of fed‐batch fermentation processes by graphical methods
Authors: Shioya Suteaki , Dunn Irving J. 
Published: July 2010

AbstractGraphical methods are used for many types of engineering calculations. Their appeal is often related to calculational simplicity, but probably the increased understanding that accompanies a graphical calculation method is chiefly responsible for their popularity. In the present work existing graphical concepts which have been used in chemical reaction engineering and fermentation technology have been extended to allow the calculation of biomass and product formation for a variety of fermentation processes. Comparisons in productivity are made among chemostat, batch, fed batch with variable and constant feed rate, and cyclic fed‐batch operations.
Biological effects of solvent extraction chemicals on aquatic organisms
Authors: Dave GÖRan , Blanck Hans , Gustafsson Kersti 
Published: July 2010

AbstractAquatic environments are the main recipient for chemicals lost from solvent extraction plants. Therefore, the toxicity of these chemicals to aquatic organisms must be considered. So far the effects of solvent extraction chemicals on aquatic organisms have been underestimated. The toxicity of some commonly employed solvent extraction chemicals to a green alga, Chlorella emersonii, a fish, Salmo gairdneri, and two cellulose‐degrading bacteria, Cellulomonas sp. and Sporocytophaga myxococcoides, are reported. For most aliphatic amines studied (Primene JM‐T, Amberlite LA‐1, Adogen 283, Alamine 336 and Aliquat 336) inhibition of growth (algae and bacteria) and mortality of fish are shown at nominal concentrations below 1 mg dm−3 (EC50s and LC50s). Other chemicals tested (Adogen 383, TBP, HDEHP, NA SUL AS‐50, LIX 64N, Versatic 10 and 2‐ethylhexanol) are less toxic, having EC50s for inhibition of growth and/or LC50s between 0.3 and 100 mg dm−3. The acute toxicity to fish is shown to be dependent on ambient temperature for all chemicals studied. Solvent extraction chemicals spread into the environment have the potential to produce toxic effects on aquatic organisms. It is therefore recommended that the status of aquatic life in natural waters receiving solvent extraction chemicals is monitored.
Glyoxal as a possible curing agent for paints based on sodium silicate
Authors: Glasser Lesley S. Dent , Grassick Eoin G. , Lachowski Eric E. 
Published: July 2010

AbstractThe effects of adding glyoxal to sodium silicate solutions have been investigated and compared with those of adding glycollic acid or hydrochloric acid: gel‐time and the proportions of small silicate units in the solutions were both studied. It is concluded that the effect of adding glycollic acid is the same as that of adding HCI and that the effect of adding glyoxal is wholly accounted for by its conversion to glycollic acid through a Cannizzaro reaction.
New terpenoid dyes, 3‐arylazocamphor derivatives: Dyeing performance and fastness properties
Authors: Kaddah Ahmed M. , Khalil Abdulgalil M. , Tawfik Nizar I. , Hamouri Abdulghani 
Published: July 2010

AbstractThe 3‐arylazocamphor (I–VI) and 3‐arylazocamphor‐2‐oxime (VII–XI) dyes were prepared, for use as azodisperse dyes by coupling camphor or camphoroxime respectively with the appropriate diazonium salt in cold ethanol containing sodium acetate solution (10%). The structure of these compounds (I–XI) was established by studying their elemental analysis, i.r. and u.v. spectra. The effect of the nature and position of substituent in the arylazo moiety on the colour, dyeing behaviour, rate of exhaustion and fastness properties when applied to protein and man‐made fibres were discussed. The effect of after‐treatment with different metal salts on the dyed woollen fibre was also investigated.
Influence of heat generated on adsorption in bidisperse adsorbents
Authors: Kočiřík Milan , Kärger Jörg , Zikánová Arlette 
Published: July 2010

AbstractSorption behaviour in adsorbate‐adsorbent systems can be considerably influenced by adsorption heat generation. General relations for sorption in bidisperse adsorbents, represented by zeolites, are derived. One limiting case is treated analytically assuming mass transport in the interior of the crystallites and heat transport in the zeolite pellets to be fast compared both with mass transport in the intercrystalline space and with the heat dissipation into the surroundings of the zeolite pellets. The first statistical moment of the sorption curve is given and applied to the interpretation of kinetic data in the cyclohexane‐13X zeolite system.
Kinetics of absorption of chlorine in acetic acid in the presence of homogeneous catalysts
Authors: Kumar Suresh , Gehlawat Jagdish K. 
Published: July 2010

AbstractThe physical solubility of chlorine in acetic acid is sufficiently large (=1.00 mol dm−3 at 333 K) to enable the kinetics of reaction between chlorine and acetic acid to be determined in the homogeneous phase. The product of reaction, monochloroacetic acid, is industrially important. The solubility of chlorine in acetic acid and monochloroacetic acid was determined. The homogeneous reaction kinetics between chlorine and acetic acid were studied using acetyl chloride and ferric chloride as catalysts. The heterogeneous kinetics of absorption of chlorine in acetic acid in the presence of ferric chloride as soluble catalyst was studied in a 10 cm agitated glass reactor. The reaction between dissolved chlorine and acetic acid was found to be very slow. In the agitated reactor the diffusion effects were completely eliminated and the reaction followed homogeneous kinetics. It was first order both with respect to chlorine as well as acetic acid. The values of second order rate constant were 2.9 × 10−5 and 13.7 × 10−5 dm3 mol−1 s−1 at 333 and 353 K, respectively.
Improvement of amyloglucosidase production of Aspergillus awamori by mutagenic treatments
Authors: Nevalainen K. M. Helena , Palva E. Tapio 
Published: July 2010

AbstractMutants with increased properties of amyloglucosidase production were isolated from Aspergillus awamori after mutagen treatments. The improvement achieved in three sequential steps of mutagen treatment and screening was 2.5‐fold. Clearly improved amyloglucosidase production was also obtained in fermentor cultivations. The production of α‐amylase was also increased in the mutants.
Conductometric study of ion association in some polyelectrolytes
Authors: Islam S. Serajul , Rahman M. Lutfer 
Published: July 2010

AbstractConductances of sodium alginate, sodium carboxymethylcellulose and sodium carboxymethyl dextran solutions have been measured in the presence of sodium chloride. It has been found that the sum of the specific conductances of the components measured separately is always greater than the specific conductance of the mixture. The difference in specific conductance between the sum and the mixture, Δ, has been studied as a function of the polyelectrolyte concentration, concentration of sodium chloride and also temperature. An attempt has been made to interpret the results in terms of both electrostatic effects and the Donnan theory of membrane equilibrium. The latter approach does not seem satisfactory.
The miniloop: A small‐scale air‐lift microbial culture vessel and photobiological reactor
Authors: Pirt S. John , Panikov Nicolai , Lee Yuan‐Kun 
Published: July 2010

AbstractThe miniloop culture vessel provides a simple means of obtaining high oxygen transfer rates in a small scale (10 cm3) reactor. The reactor contains no moving parts. The volumetric oxygen transfer rate (measured by Cu2+ catalysed sulphite oxidation) exceeded 400 h−1. The high surface: volume ratio (12 cm−1) permitted photosynthetic algal cultures with biomass densities over 35 g dm−3 in chemostat steady‐states.
Kinetics and mechanism of the vapour‐phase ammoxidation of 4‐picoline
Authors: Das Asis , Kar Anil K. 
Published: July 2010

AbstractThe kinetics of the heterogeneous vapour phase ammoxidation of 4‐picoline was studied over V2O5‐Cr2O3‐Al2O3 catalysts in a differential flow reactor between 548 and 598 K and under atmospheric pressure. The rate equationmagnified imagefor the conversion of 4‐picoline to isonicotinonitrile and the rate equationmagnified imagefor the overall conversion of 4‐picoline, represented the rate data satisfactorily. The overall conversion of 4‐picoline was also tested by the Langmuir‐Hinshelwood mechanism.