bluuebunny/crossref_metadata_2025_split huggingface dataset:
Introducing a geographic information system as computer tool to apply the problem‐based learning process in public buildings indoor routing
Authors: Ariza‐Villaverde A. B. , de Ravé E. Gutiérrez , Jiménez‐Hornero F. J. , Pavón‐Domínguez P. , Muñoz‐Bermejo F. 
Published: May 2010

AbstractA geographic information system (GIS) is presented in this work with the aim of helping the application of problem‐based learning process to show the students how to adopt the appropriate decisions for the adaptation of architectural barriers to ensure the universal accessibility in public buildings. The GIS developed here consists of three layers based on vector maps corresponding to buildings, potential routes and architectural barriers. Hyperlinks in the last layer allow access to some relevant information about each barrier, such as type, description and adaptation cost. Several tests have been carried out to show the capability of the implemented GIS to locate indoor barriers, determine suitable indoor routes by considering criteria such as paths lengths or the total cost of barrier elimination, and update the information corresponding to each architectural barrier. In addition, the application of the proposed GIS has also been explored for indoor route guidance with promising results. This investigation has been carried out with the aim of being combined with the problem‐based learning process. © 2010 Wiley Periodicals, Inc. Comput Appl Eng Educ 21: 573–580, 2013
Solid‐State NMR Characterization of Wilkinson’s Catalyst Immobilized in Mesoporous SBA‐3 Silica
Authors: Grünberg Anna , Yeping Xu , Breitzke Hergen , Buntkowsky Gerd 
Published: May 2010

AbstractThe Wilkinson’s catalyst [RhCl(PPh3)3] has been immobilized inside the pores of amine functionalized mesoporous silica material SBA‐3 and The structure of the modified silica surface and the immobilized rhodium complex was determined by a combination of different solid‐state NMR methods. The successful modification of the silica surface was confirmed by 29Si CP‐MAS NMR experiments. The presence of the Tn peaks confirms the successful functionalization of the support and shows the way of binding the organic groups to the surface of the mesopores. 31P‐31P J‐resolved 2D MAS NMR experiments were conducted in order to characterize the binding of the immobilized catalyst to the amine groups of the linkers attached to the silica surface. The pure catalyst exhibits a considerable 31P‐31P J‐coupling, well resolvable in 2D MAS NMR experiments. This J‐coupling was utilized to determine the binding mode of the catalyst to the linkers on the silica surface and the number of triphenylphosphine ligands that are replaced by coordination bonds to the amine groups. From the absence of any resolvable 31P‐31P J‐coupling in off‐magic‐angle‐spinning experiments, as well as slow‐spinning MAS experiments, it is concluded, that two triphenylphosphine ligands are replaced and that the catalyst is bonded to the silica surface through two linker molecules.
Effect of method of preparation on activity of Pd/Al2O3 monolith catalysts
Authors: Mogalicherla Aswani Kumar , Kunzru Deepak 
Published: May 2010

AbstractPd/Al2O3 monolithic catalyst of different washcoat thicknesses were prepared by two methods and tested for the activity of hydrogenation of α‐methyl styrene. These catalysts were prepared by two methods; either the palladium was impregnated on γ‐alumina and this Pd/Al2O3 powder was used to prepare the slurry for washcoating (Cat 1) or γ‐alumina washcoating was followed by impregnation of palladium (Cat 2). The effect of slurry concentration, pH of the slurry, and addition of binders on the catalyst properties was investigated. The monolithic catalysts were characterised by determination of metal dispersion, surface area, scanning electron microscopy, and weight loss of washcoat during ultrasonication. Well‐adhered washcoats were obtained with slurry prepared using milled γ‐alumina, whereas the adhesion of the washcoat prepared using Pd/Al2O3 powders was very poor. Addition of binders significantly improved the adhesion of the washcoats prepared from Pd/Al2O3. Metal dispersion for Cat 2 decreased with washcoat loading but did not change with loading for Cat 1. The activity tests were conducted at different washcoat loadings and the productivity of the monolithic catalyst prepared in both methods has been compared.
Effect of wall velocities on the determination of optimal separation times in electrical field flow fractionation (EFFF)
Authors: Pascal Jennifer , Oyanader Mario , Arce Pedro E. 
Published: May 2010

AbstractElectrical field flow fractionation (EFFF) has two perpendicular driving forces that help to produce an optimal separation of solute in a mixture [Giddings, Science 1993; 260:1456–1465]. For Couette flow based devices, the ratio of the velocity of the capillary walls offers an extra parameter that can be exploited to enhance the efficiency of EFFF applications. The analysis of the effects of this parameter on optimal times of separation is the subject matter of this contribution. The use of this additional parameter increases flexibility in the design of new devices for the improvement of the separation of solutes, such as proteins, DNA, and pharmaceuticals, as it will be illustrated with the results of this analysis (Jaroszeski et al., 2000; Trinh et al., 1999). The analysis has been illustrated by selecting parameter values that represent a number of potential useful applications. A set of five parameters (i.e., z, the valence; µ, electrophoretic mobility; Pe, Peclet number; Ω, the orthogonal applied electrical field; and R, the ratio of channel wall velocities) has been combined to obtain the best operating conditions for optimal separation of solutes. Results indicate that R, the ratio of the channel wall velocities, is actually the most important driving parameter.
Direct meso‐scale simulations of fibres in turbulent liquid flow
Authors: Derksen J. J. 
Published: May 2010

AbstractA procedure for direct, meso‐scale simulations of flexible fibres immersed in liquid flow is introduced. The fibres are composed of chains of spherical particles connected through ball joints with the bending stiffness of the joints as a variable. The motion of the fibres and the liquid is two‐way coupled with full resolution of the solid–liquid interface. First the simulation procedure is validated by means of an analytical solution for sphere doublets in zero‐Reynolds simple shear flow. Subsequently we use the numerical method to study inertial flows with fibres, more specifically the interaction of a fibre with isotropic turbulence.
Development of airlift bubble column dispersed with micro‐bubbles
Authors: Yasuda Keiji , Wang Yufei , Haneda Koichi , Naito Testuya , Bando Yoshiyuki , Takeyama Tomokiyo , Kawase Yasuhito 
Published: May 2010

AbstractMicro‐bubbles were dispersed in the bubble column with draft tube, and the length and diameter of draft tube were changed. The flow characteristics in air–water system were measured. Ozone gas and methylene‐blue aqueous solution were used, and the decomposition performance was examined. With increasing draft tube length, both the gas holdup and liquid velocity in the annular section increased. When the diameter ratio of draft tube to column was about 0.5, both the gas holdup and liquid circulation flow rate had maxima. For the decomposition by using ozone, the installation of draft tube enhanced the mass transfer and decomposition performance.
Gas–liquid interfacial area in the oxygen absorption to oil‐in‐water emulsions in an airlift reactor
Authors: Gómez‐Díaz D. , Gomes N. , Teixeira J. A. , Belo I. 
Published: May 2010

AbstractThe present work includes an exhaustive study about gas–liquid interfacial area between gas phase and liquid heterogeneous medium generated in an airlift bioreactor. The system studied is composed by water, methyl ricinoleate (MR), and Tween‐80, since it is the base of the medium used for the production of γ‐decalactone, a peach‐like aroma compound of industrial interest that can be produced biotechnologically through the biotransformation of ricinoleic acid, by the yeast Yarrowia lipolytica. Experimental results allow describing the hydrodynamic behaviour of the gas phase into the biphasic medium.
Simulation of direct leaching of zinc concentrate in a non‐ideally mixed CSTR
Authors: Lampinen Matti , Laari Arto , Turunen Ilkka 
Published: May 2010

AbstractA simulation model for direct leaching of zinc concentrate in a continuous non‐ideally mixed stirred tank reactor (CSTR) is presented. The model takes into account the surface reactions between zinc in the solids and ferric iron ions in the liquid phase, oxidation of ferrous iron back to ferric iron, gas–liquid mass transfer of oxygen, decrease of particle size as the reaction proceeds, and the effect of hydrostatic pressure on the oxygen dissolution rate. The model is pseudo‐homogeneous and is approximative in the sense that it neglects the effects of particle size distributions and population balances of the concentrate particles.
Determination of tanshinone I, tanshinone IIA, and cryptotanshinone in Salvia miltiorrhiza bunge and urine sample by HPLC
Authors: Tian Minglei , Row Kyung Ho 
Published: May 2010

AbstractA simple and sensitive HPLC method to detect tanshinone I, tanshinone IIA, and cryptotanshinone in human urine was developed and validated. Chromatographic separation was achieved on a C18 column (4.6 mm × 250 mm, 5 µm) using a mixture of methanol/water (78:22 v/v, containing 0.5% acetic acid) as the mobile phase at a flow rate of 0.5 mL/min with UV detector at 254 nm. The calibration curve of tanshinones was linear over a range of 1.0 × 10−4 – 1.0 mg/mL. The limit of quantification (LOQ) was found to be 57.0, 76.0, and 45.0 ng/mL, respectively. This method can estimate the pharmacokinetic parameters of tanshinones in human urine after the intravenous and intraperitoneal administration of stanchions.
Effect of solid material and surfactant presence on interactions of bubbles with horizontal solid surface
Authors: Fujasová‐Zedníková Mária , Vobecká Lucie , Vejrazka Jiri 
Published: May 2010

AbstractThe interaction of a bubble with an immersed horizontal solid surface is studied experimentally. The effect of presence of a surfactant (limited to a specific nonionic surfactant, α‐terpineol, of various concentrations) and of surface material (cleaned glass, polypropylene, polyethylene, and Teflon) is investigated. The study focuses on two particular stages of the interaction, (i) the process of bubble bounce, which includes a collision and subsequent rebound from the solid surface, and (ii) the bubble attachment, which occurs after collision in time much longer than the duration of bounce and also after disappearance of all visible bubble movement. It is observed that the effect of the surface material on the bouncing is minor, possibly due to the liquid film separating the bubble and the solid surface. The presence of surfactant significantly affects the bouncing process. It not only decreases the initial bubble velocity, but also diminishes the bubble deformation after the collision and suppresses the bubble rebound from the surface. No rebound from the surface is observed in the most concentrated (1 × 10−3 mol/L) α‐terpineol solution. The adhesion time depends both on the solid material and α‐terpineol concentration. If the α‐terpineol concentration is increased, the adhesion time increases in the case of polypropylene surface, while it decreases in the case of polyethylene and Teflon surfaces. Results of this study are relevant for the description of attachment mechanism and to determine the proper conditions for selective flotation of plastics.
Kinetics and mass transfer in hydroformylation—bulk or film reaction?
Authors: Bernas Andreas , Wärnå Johan , Mäki‐Arvela Päivi , Murzin Dmitry Yu , Salmi Tapio 
Published: May 2010

AbstractThe kinetics of a gas–liquid reaction, alkene hydroformylation was studied in the presence of a homogeneous catalyst in a pressurised laboratory‐scale semibatch reactor. Hydroformylation of propene to isobutyraldehyde and n‐butyraldehyde was carried out at 70–115°C and 1–15 bar pressure in 2,2,4‐trimethyl‐1,3‐pentanediol monoisobutyrate solvent with rhodium catalyst using the ligands cyclohexyl diphenylphosphine. In order to evaluate the influence of mass transfer, experiments were made using varied stirring rate from 100 to 1000 rpm at 100°C and 10 MPa syngas pressure. Only at higher stirrings rates, the reaction took place in the kinetic regime. A reactor model was developed comprising both complex kinetics and liquid‐phase mass transfer. The model was based on the theory of reactive films. The model is able to predict under which circumstances the hydroformylation process is affected by liquid‐phase diffusion of the reactants. Experimental data and model simulations are presented for the hydroformylation of propene in the presence of a homogeneous rhodium catalyst.
Organic coated solids in athabasca bitumen: Characterization and process implications
Authors: Bensebaa Farid , Kotlyar Luba S. , Sparks Bryan D. , Chung Keng H. 
Published: May 2010

AbstractBitumen, separated from oil sands by the hot water extraction process, contains ultra‐fine (< 200 nm), inorganic solids (BS). Surfaces of BS particles are coated with toluene insoluble organic matter (TIOM). This organic material is polar and aromatic with contributions from both humic and asphaltene‐like components. Although the surfaces of BS particles are dominated by TIOM, the coverage is patchy rather than continuous. As a result, these solids are capable of stabilizing fine water emulsions in the bitumen phase. The nature of the organic matter on the surfaces of the particles is such that it has a high propensity to form coke. Therefore, these particles can also play a role in fouling on equipment and catalysts.
Modelling transverse mixing in a rolling drum
Authors: Van Puyvelde Dennis R. , Wilson Michael A. , Young Brent R. , Schmidt S. James 
Published: May 2010

AbstractIn this paper, a new model of transverse mixing in a rotating drum is derived from dynamic data collected from an experimental rig. Since the active layer has often been declared as the zone that is responsible for the mixing of solids in a rolling bed, the active layer was characterized so that its properties could be predicted for a wide range of experimental conditions. The mixing model consisted of two correlations, one to predict the mixing rate in the drum and the other to predict the final contact between the two materials. These correlations were linked back to the operational variables of the drum, such as the drumfs loading, size and rotational velocity. By combining these two correlations the time required to fully mix the material in the drum could be predicted. The mixing model was tested against independent data and good agreement was observed between the experimentally derived results and those predicted by the mixing model. Furthermore, this mixing model was designed such that it would be easily applicable to different sized drums. The extrapolation ability was tested on different smaller‐sized drums and found to agree considerably with experimental results.
Control of fines suspension density in the fines loop of a continuous KCl crystallizer using transmittance measurement and an FBRM® probe
Authors: Tadayyon Abdulsamad , Rohani Sohrab 
Published: May 2010

AbstractThe control of crystal size distribution (CSD) is investigated in a 1.5 L laboratory cooling KCl crystallizer using fines dissolution rate as the manipulated variable. The controlled variable was either the fines suspension density in the fines withdrawal loop, measured by an innovative double‐sensor turbidity meter manufactured in‐house, or the chord length distribution (CLD) measured by the Focused Beam Reflectance Measurement (FBRM®) probe (model: Par‐Tec® 100, Lasentec®, Redmond, WA). It was shown that effective control of mean crystal size and fines suspension density in the presence of setpoint and disturbance changes is feasible with both control schemes. The double sensor turbidity sensor proved to be very rugged even in the presence of insoluble clay background particles. The FBRM® probe was more sensitive and capable of detecting particle breakage and flocculation.
Imaging in powder technology from visualization to measurement: Application to shape quantification
Authors: Vivier Hervé , Pons Marie‐Noëlle , Bernard‐Michel Bruno 
Published: May 2010

AbstractImage analysis tools and statistical procedures have been developed to quantify particle shape. Three copper sulfate crystallization processes have been carried out and the effects of process operating parameters upon crystal morphology have been studied as well as the relationships between morphology and powder end use properties. Both aspects give the capability to master end‐use properties by the process parameters. It is also shown that size distribution without morphology is deficient to globally characterize a powder and to describe its behaviour.
Deposition velocities for newtonian slurries in turbulent flow
Authors: Gillies Randall G. , Schaan Jason , Sumner Robert J. , McKibben Melissa J. , Shook Clifton A. 
Published: May 2010

AbstractIn this contribution both new and previously published deposition velocity data for aqueous Newtonian slurries are incorporated in a correlation which complements the earlier predictions of Durand, Wilson and A.D. Thomas. Most of the new data has been obtained for slurries of narrowly sized sand particles of median diameter ranging between 90 and 420 μm, in pipes of diameter between 0.05 and 0.5 m. The data were obtained in laboratory investigations under isothermal flow conditions.
A laboratory investigation of horizontal well heavy oil—water flows
Authors: McKibben Melissa J. , Gillies Randall G. , Shook Clifton A. 
Published: May 2010

AbstractExperimental simulations of model well‐bore flows in laboratory pipelines show that frictional energy losses (i.e., pressure drops) are reduced when water is present with heavy oil. The reduction has been shown to increase with the water fraction. The mixtures are not oil in water emulsions in the classical sense of the term. At the low axial velocities which characterize wellbore flows, the flow regime is inherently intermittent. Using a variety of methods the structure of the flow has been examined to identify the flow regime and the cause of the reduced pressure gradients. It has been found that the water travels as large slugs and that oil is invariably present at the wall when the mixture flows through a steel pipe. The evidence suggests that a significant fraction of the oil is transported within the water slugs. A tentative flow regime boundary between the regions of intermittent and continuous water‐assisted flow is proposed in terms of the mixture Froude number and the injected water fraction.
Predicting pressure gradients in heavy oil—water pipelines
Authors: McKibben Melissa J. , Gillies Randall G. , Shook Clifton A. 
Published: May 2010

AbstractExperimental investigations of the flow of water‐heavy oil mixtures at velocities typical of oil‐field gathering systems show that continuous water assisted flow at very low pressure gradients can be achieved. The principal criterion to be satisfied in establishing this desirable flow regime appears to be use of sufficient water, with the velocity also playing a role. It also appears that oil viscosity and water fraction effects on pressure gradient are small provided the beneficial flow regime is established. The flows resemble core‐annular flow, which has been observed previously in Bitumen froth and water‐heavy oil flows, with an oil layer on the pipe wall. However, the correlation for pressure gradient is somewhat different from that reported previously for Bitumen froth flows.
Une nouvelle technologie d'appareils de dépôt chimique en phase vapeur. Partie 1 : Présentation et analyse des résultats expérimentaux
Authors: Vergnes Hugues , Duverneuil Patrick , Couderc Jean‐Pierre 
Published: May 2010

AbstractCet article présente une nouvelle technologie d'appareils de dépôt chimique en phase vapeur qui a été développée afin de supprimer plusieurs problèmes rencontrés dans l'industrie microélectronique. En outre, cette technologie permet de concevoir un modèle réduit parfaitement représentatif du réacteur industriel, très utile pour effectuer des développements plus rationnels de nouvelles applications. La première partie de cet article décrit les réacteurs puis présente et analyse un ensemble de résultats expérimentaux. Quatre types de dépôts, de complexité croissante, ont été choisis pour effectuer une comparaison détaillée entre les performances de la nouvelle technologie et celles des réacteurs que les industries microélectroniques utilisent classiquement.
Effects of pressure and impingement angle in flaming processes
Authors: Liakos Harilaos H. , Koukou Maria K. , Markatos Nikolaos C. , Founti Maria A. 
Published: May 2010

AbstractThis work investigates the effects of varying the pressure of the mixture reactants and the angle of impingement on the performance characteristics of a turbulent premixed jet flame impinging on a solid surface. These effects are important for the design of torches and flaming machines used for material and metal cutting and forming. The combustion and flow characteristics are modelled using a finite volume computational approach. Based on the simulation results, it is shown that, by increasing the pressure of the mixture reactants, the flame‐surface interaction mechanisms are modified. Changing the impingement angle increases the role of chemical kinetics and reduces maximum temperature values due to increased local flame extinction. The heat released and temperature predictions are compared to experimental data and the agreement is satisfactory.
Formation of needle‐like lepidocrocite fine particles by oxidation of an aqueous suspension of ferrous hydroxide in a bubble column
Authors: Cho Hae‐Man , Kawasaki Hiroyuki , Kumazawa Hidehiro 
Published: May 2010

AbstractFine particles of needle‐like lepidocrocite (γ‐FeOOH) were synthesized by the oxidation of aqueous suspensions of ferrous hydroxide using a bubble column with draft tube at a constant temperature ranging from 20°C to 30°C. The oxidation steps leading to green rust (an intermediate) and lepidocrocite (final product), termed Step I and II, respectively, could be described apparently as first order, with respect to oxygen, and zero order, with respect to total ferrous species. When the concentration of oxygen in the feed stream was varied under a constant gas velocity, the mean size based on the major axis of needle‐like particle decreased from 0.60 to 0.35 μm with increasing oxidation rate. When the gas velocity was varied under a constant oxygen concentration, the particle size was almost independent of the oxidation rate and was equal to ca. 0.6 μm. By the addition of a small amount of sodium dihydrogenphosphate (NaH2PO4), the major axis could be reduced to 0.2 μm with the minor axis and the oxidation rate almost unchanged.