bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dispersion and slip effects in hydraulic hoisting of solids
Authors: Evans J. , Shook C. A. 
Published: March 2009

AbstractConcentration changes which occur in cyclical hydraulic hoisting operations can be modelled with a form of the convection‐diffusion equation. In order to solve this equation it is necessary to specify the axial dispersion coefficient and the effective slip of the particles relative to the mean velocity. The effective slip depends upon drag and particle migration effects.Experimental observations of these concentration changes are interpreted with numerical solutions of the appropriate equation. Fine particles develop a near‐Gaussian concentration distribution while coarse particles produce a saw‐tooth pulse. Axial dispersion coefficients are similar to those observed with solutes in turbulent slurry flows and slip velocities are shown to be concentration dependent.
Heat transfer and gas holdup studies in a bubble column: Air‐water‐sand system
Authors: Saxena S. C. , Rao N. S. , Saxena A. C. 
Published: March 2009

AbstractAir‐holdup and heat transfer coefficient data are reported for the air‐water and air‐water‐sand system as a function of air velocity in the temperature range 297‐343 K as measured in a 0.305 m diameter bubble column operating in semi‐batch mode and equipped with either a five‐ or seven‐tube bundle. A 65 μm average size sand powder is used at concentrations of 5 and 10 mass percent in the slurry. Available correlations of gas holdup and heat transfer coefficients are examined on the basis of these data. These are found inappropriate and inadequate for representing these experimental data. Gas holdup data are well represented by an approach based on Nicklin's (1962) work, and heat transfer data are adequately represented by a simple semi‐empirical expression. Accurate experimental data on additional systems are needed to develop a reliable heat transfer theory particularly for process representation at temperatures higher than ambient.
The internally circulating fluidized bed (ICFB): A novel solution to gas bypassing in spouted beds
Authors: Milne Bruce J. , Berruti Franco , Behie Leo A. , De Bruijn Theo J. W. 
Published: March 2009

AbstractThe bypassing of a portion of the inlet spout gas to the annular region of spouted and spout‐fluid beds can have a critical effect on processes requiring accurate control of the spout gas residence time even when a draft tube is utilized. A modification to the spout‐fluid bed with draft tube called the Internally Circulating Fluidized Bed or ICFB is proposed which eliminates this bypassing problem. Experiments were conducted on a cold 20 cm diameter semi‐cylindrical unit to define the operational characteristics of the ICFB with particular emphasis on the gas and solids flow behavior. The solids and gas flow rates in the unit were successfully related by a published correlation which was developed for the cocurrent flow of gases and solids through orifices.
Drying characteristics in a jet‐spouted bed dryer
Authors: Markowski A. S. 
Published: March 2009

AbstractA conical jet‐spouted bed dryer with inert bodies was used for drying of animal blood plasma. The effects of the operating conditions on the product properties, final moisture content and throughput of the dryer were investigated. A drying rate model using the conventional rate equation, where the overall effective driving force is based on the surface temperature calculated from the unsteady‐state heat transfer Fourier equation, was proposed. Satisfactory agreement between calculated and experimental results was obtained.
Fours rotatifs: Modèle dynamique du mouvement du lit
Authors: Perron J. , Bui R. T. 
Published: March 2009

AbstractThe motions of the granular bed inside a rotary furnace are governed by complex dynamics consisting of two modes. The axial velocity of the active layer on top of the bed represents the fast mode, while the overall velocity in the bed follows a slower mode. The proposed nonlinear model focuses on the dynamics of the slow mode. The difficulties of an analytic solution are avoided by a numerical method that employs several correlations. The model can reproduce the experimental transient responses. It is concluded that rotary furnaces respond better to small amplitude excitations than to large ones; consequently, closed‐loop control is well suited for this type of furnace.
Bubble size distribution in a flotation column
Authors: Biswal S. K. , Reddy P. S. R. , Bhaumik S. K. 
Published: March 2009

AbstractThe bubbles that were generated in a flotation column were measured. The bubble size distributions were obtained both for air‐water and air‐water‐coal systems. The size distribution pattern was fitted to different equations. It was found that the bubble size distribution in both the flotation and cleaning zones follows the Rosin‐Rommler equation used to describe the particle size distribution in crushing. This study indicates that bubbles in the cleaning zone are always larger than those of the flotation zone and finer bubbles are generated when a mixture of frothers is used instead of individual frothers.
Drying paper by impinging jets of superheated steam. Part 1: Constant drying rate in superheated steam
Authors: Bond J. F. , Mujumdar A. S. , van Heiningen A. R. P. , Douglas W. J. M. 
Published: March 2009

AbstractOver a wide range of operating conditions, the drying of paper by impinging jets of superheated steam proceeds by a constant rate period followed by a falling rate period. The constant drying rate, investigated here in the jet temperature range 150 ≤ Tj/ ≤ 465°C and over jet Reynolds numbers of 1000 ≤ Rej ≤ 12000, is predicted within + 12% by a heat transfer expression using Martin's (1977) correlation for the heat transfer coefficient corrected for mass transfer by the Couette flow approximation factor, and a property ratio to account for the large temperature difference between the jet and the paper.
Gas evolution from the aquathermolysis of heavy oils
Authors: Belgrave J. D. M. , Moore R. G. , Ursenbach M. G. 
Published: March 2009

AbstractAquathermolysis experiments were performed on core samples taken from three large bitumen and heavy oil deposits found in Alberta, to investigate gas evolution over the temperature range 360 to 420°C. Experiments conducted on Athabasca included runs with an initially pre‐oxidized oil sample and runs with a change in core mineralogy. Pre‐oxidizing the oil was found to substantially increase the amount of carbon monoxide and molecular hydrogen generated. Core mineralogy played an important role in the generation of carbon dioxide, and the amount of hydrogen sulphide produced was dependent on oil composition, mineralogy and time. Although substantial amounts of gaseous products are produced by simple thermolysis reactions (i.e., without water present), the main thermal recovery methods, steam injection and in‐situ combustion, bring the oil phase and its host rock into direct contact with water. As water has been shown to take part in thermal cracking reactions, these experiments provide usful data for the estimation of produced gas composition during thermal recovery projects.
Effets de differents parametres sur les vitesses de transition de la fluidisation en regime turbulent
Authors: Chehbouni A. , Chaouki J. , Guy C. , Klvana Et D. 
Published: March 2009

AbstractUne grande controverse existe dans la littérature concemant les effets de différentes variables sur les vitesses de transition de la fluidisation turbulente. A la lumière des résultats de la littérature, quatre paramètres ont été choisis: le diamètre de la colonne, le nombre d'Archimède, la hauteur initiale du lit et la distribution de diamètre des particules. Pour caractériser l'effet de ces quatre paramètres hydrodynamiques sur la vitesse de début du régime turbulent Uc et sur la vitesse de transport Utr, nous avons réalisé des expériences selon un plan expérimental de type Plackett‐Burman à huit essais pour Uc et Utr. Les facteurs et leurs niveaux de variation sont: (a) diamètre de la colonne (82 vs 200 mm), (b) particules (FCC vs sable), (d) hauteur statique du lit (300 vs 450 mm) et (g) distribution des particules (étroite vs large). Pour déterminer expérimentalement ces deux vitesses de transition, nous avons utilisé un capteur de pression différentiel et une sonde à capacitance. Les résultats expérimentaux et l'analyse statistique montrent que le diamètre de la colonne est le facteur le plus important (61% de variabilité pour Uc et 51% pour Utr). Les propriétés du solide (ρp, dp) viennent en deuxième lieu (35% de variabilité pour Uc et 47% pour Utr). L'effet de la hauteur statique est très faible et la distribution des particules n'a pratiquement pas d'effet sur les deux vitesses. Les résultats montrent aussi qu'il n'y a pas d'interactions entre ces paramètres. Enfin, nous avons proposé deux corrélations pour prédire Uc et Utr qui font intervenir le diamètre du réacteur.
Algebraic multigrid, mixed‐order interpolation, and incompressible fluid flow
Authors: Webster R. 
Published: March 2009

AbstractThis paper presents the results of numerical experiments on the use of equal‐order and mixed‐order interpolations in algebraic multigrid (AMG) solvers for the fully coupled equations of incompressible fluid flow. Several standard test problems are addressed for Reynolds numbers spanning the laminar range. The range of unstructured meshes spans over two orders of problem size (over one order of mesh bandwidth). Deficiencies in performance are identified for AMG based on equal‐order interpolations (both zero‐order and first‐order). They take the form of poor, fragile, mesh‐dependent convergence rates. The evidence suggests that a degraded representation of the inter‐field coupling in the coarse‐grid approximation is the cause. Mixed‐order interpolation (first‐order for the vectors, zero‐order for the scalars) is shown to address these deficiencies. Convergence is then robust, independent of the number of coarse grids and (almost) of the mesh bandwidth. The AMG algorithms used are reviewed. Copyright © 2009 John Wiley & Sons, Ltd.
Embryonic Stem Cells and Mammary Luminal Progenitors Directly Sense and Respond to Microbial Products
Authors: Lee Sung-Hyung , Hong Bangxing , Sharabi Andrew , Huang Xue F. , Chen Si-Yi 
Published: March 2009

Abstract
Stem cells are normally maintained in a quiescent state and proliferate only under certain conditions; however, little is known about the biological stimuli that initiate the proliferation and differentiation of stem cells. In this study, we found that functional Toll-like receptors (TLRs) are expressed on mouse embryonic stem (ES) cells and that TLR ligands stimulate ES cell proliferation and promote their hematopoietic differentiation. TLR ligands activate TLR-mediated signaling pathways, leading to the altered expression of numerous genes in ES cells. Moreover, TLR ligands efficiently stimulate the proliferation and expansion of adult stem cells and progenitors of nonhematopoietic tissues, such as mammary glands and intestine as well. We further found that mammary luminal progenitor cells (Lin−CD29+CD61+) express TLR4-MD2 complex and actively proliferate, resulting in the enhanced growth of mammospheres in response to TLR ligands. Thus, mouse ES cells and adult tissue-specific stem cells/progenitors directly sense and respond to microbial products, which function as a class of foreign, but biological stimuli for stem cell/progenitor proliferation. This finding expands the biological role of TLRs and has implications in understanding stem cell biology, tissue repair/homeostasis, and the role of infection and inflammation in malignant transformation.
Disclosure of potential conflicts of interest is found at the end of this article.
Evaluation of therapeutic effects on rectal varices using percutaneous color Doppler ultrasonography
Authors: Sato Takahiro , Yamazaki Katsu , Toyota Jouji , Karino Yoshiyasu , Ohmura Takumi , Akaike Jun 
Published: March 2009

Aim:  We report the usefulness of percutaneous color Doppler ultrasonography (CDU) for evaluating therapeutic effects on rectal varices.Methods:  Ultrasonographic examination and color flow imaging were performed using a color Doppler unit (Aplio 50 or XV, Toshiba, Tokyo, Japan) with a 3.5 MHz convex probe. We performed endoscopic injection sclerotherapy (EIS) for rectal varices in seven patients and partial splenic arterial embolization (PSE) for hypersplenism in four. We examined color flow images and measured the velocity of blood flow in rectal varices using fast‐Fourier transform analysis by CDU in all eleven patients, before and after treatments.Results:  Rectal varices were detected by Doppler color flow imaging in all eleven patients before treatments. Blood flowvelocity in the rectal varices ranged from 5.7–11.6 cm/s (mean 8.6 cm/s). Rectal varices were observed in all patients by colonoscopy; enlarged, tortuous large varices with red color sign in nine and enlarged, tortuous large varices without red color in two. Seven days after EIS or PSE, CDU showed an extreme decrease in blood flow in all eleven rectal varices, compared to values before EIS or PSE.Conclusions:  CDU can be performed repeatedly and is useful for evaluating the therapeutic effects of treatments for rectal varices.
Therapeutic benefits of partial splenic embolization for thrombocytopenia in hepatocellular carcinoma patients treated with radiofrequency ablation
Authors: Hidaka Hisashi , Kokubu Shigehiro , Nakazawa Takahide , Minamino Tsutomu , Takada Juichi , Tanaka Yoshiaki , Okuwaki Yusuke , Watanabe Masaaki , Shibuya Akitaka , Saigenji Katsunori 
Published: March 2009

Aim:  Partial splenic embolization (PSE) is a non‐surgical procedure developed to treat hypersplenism. The purpose of this study is to evaluate therapeutic benefits of PSE with follow‐up radiofrequency ablation (RFA) treatment in hepatocellular carcinoma (HCC) patients with thrombocytopenia.Methods:  Between September 1999 and January 2007, a total of 20 patients with HCC who had a few lesions, each 3 cm or less in diameter, and liver function of Child‐Pugh class A or B were enrolled into our study. The patients were diagnosed with marked thrombocytopenia (<50 × 103/mm3), or mild thrombocytopenia (<80 × 103/mm3) with decreased prothrombin activity. They were treated once or twice with PSE. RFA was given as a follow‐up treatment 2 weeks after final PSE. The primary endpoint was a platelet‐count increase and improvement of prothrombin activity, and the secondary endpoint was the initiation of RFA.Results:  PSE was performed successfully in 19 patients (95%). Two weeks after final PSE, platelet counts increased significantly (38 ± 14 × 103/mm3 vs. 97 ± 43 × 103/mm3; P < 0.0001), and prothrombin activity improved significantly (59.3 ± 19.8% vs. 65.2 ± 17.9%; P < 0.0001). No patients had major complications during the PSE procedure. The secondary endpoint was achieved in 18 of 19 patients (94.7%). The mean overall survival was 2257 days (95% confidence interval; range, 1659−2855 days). The Kaplan‐Meier cumulative survival rate was estimated to be 61.9% at 5 years.Conclusions:  PSE is a safe and effective treatment for thrombocytopenia and has adjuvant therapeutic benefits for the therapy of HCC.
Cognitive Function Is Disrupted by Both Hypo- and Hyperglycemia in School-AgedChildren With Type 1 Diabetes: A Field Study
Authors: Gonder-Frederick Linda A. , Zrebiec John F. , Bauchowitz Andrea U. , Ritterband LeeM. , Magee Joshua C. , Cox Daniel J. , Clarke William L. 
Published: March 2009

OBJECTIVE
We developed a field procedure using personal digital assistant (PDA) technology to test the hypothesis that naturally occurring episodes of hypo- and hyperglycemia are associated with deterioration in cognitive function in children with type 1 diabetes.

RESEARCH DESIGN AND METHODS
A total of 61 children aged 6–11 years with type 1 diabetes received a PDA programmed with two brief cognitive tests (mental math and choice reaction time), which they completed just before home glucose readings. The computer recorded time to complete each test and number of correct responses. Children completed several trials per day over 4–6 weeks for a total of 70 trials. Performance variables were compared across glucose ranges. Individual impairment scores (IISs) were also computed for each child by calculating the SD between performance during euglycemia and that during glucose extremes.

RESULTS
Time to complete both mental math and reaction time was significantly longer during hypoglycemia. During hyperglycemia, time to complete math was significantly longer and reaction time was marginally significant (P = 0.053). There were no differences on task accuracy. Decline in mental math performance was equivalent at glucose levels &lt;3.0 and &gt;22.2 mmol/l. IISs varied greatly across children, with no age or sex differences.

CONCLUSIONS
A decrease in mental efficiency occurs with naturally occurring hypo- and hyperglycemic glucose fluctuations in children with type 1 diabetes, and this effect can be detected with a field procedure using PDA technology. With blood glucose levels &gt;22.2 mmol/l, cognitive deterioration equals that associated with significant hypoglycemia.
Produkteigenschaften und Verfahrenstechnik am Beispiel der Aromen
Authors: Uhlemann J. , Reiß I. 
Published: March 2009

AbstractFormulierungsverfahren gewinnen in den letzten Jahren eine immer größere Bedeutung für den Produktdesign von Aromen. War klassischerweise der Fokus des Flavoristen und der ihn unterstützenden chemischen Fachabteilungen auf der chemischen Zusammensetzung der meist flüssigen Aromen, so haben heute trockene Formulierungen und technologisch beeinflussbare Produkteigenschaften wie Haltbarkeit und kontrollierte Freisetzung ein ähnlich großes Gewicht. Für die gezielte technologische Beeinflussung von Produkteigenschaften ist die genaue Kenntnis der physiko‐chemischen Eigenschaften von Aroma‐ und Trägerstoffen von Bedeutung. Nach einer einleitenden Darstellung und Eingrenzung des Fachgebietes wird insbesondere auf neuere Fortschritte in der Verfahrenstechnik der Mikroverkapselung von Aromen und vertieft auf eigene Arbeiten zu den Verfahren Sprühtrocknung, Sprühgranulation, Extrusion, Mehrstoff‐Düsenverfahren eingegangen.
Correlation of mist‐to‐annular transition during condensation
Authors: Soliman H. M. 
Published: March 2009

AbstractA theory is proposed for correlating the mist‐annular transition during condensation based on a balance between destructive and stabilizing forces acting on the liquid film. The resulting correlation is shown to be capable of good agreement with a data base corresponding to a wide range of fluid properties and tube diameters. A fair deal of generality is demonstrated by testing the correlation outside the range from which it was developed.
Hydrodynamic characteristics of jet‐spouted beds
Authors: Markowski A. , Kaminski W. 
Published: March 2009

AbstractJet‐spouted beds characterised by high velocity gas jets (above 1.7 Umsl), and shallow bed depths H0 of around 2 D1 were investigated on laboratory scale beds and industrial scale beds and the results obtained thereof are correlated and presented in this work. Compared with the classical spouted beds, important differences in bed structure, solid movements and basic hydrodynamic characteristics were observed. The minimum spouting velocity, bed voidage and pressure drop during stabilized spouting are described in terms of dimensionless equations. Bed expansion was used as the basis for the classification of different jet‐spouting regimes (incoherent spouting, fast spouting, pneumatic conveying) and changes in the slope of the bed expansion curve are correlated with regime changes. This classification could be useful in the optimization of industrial scale jet‐spouted beds. A typically applicable regime of fast spouting was identified.
Drying characteristics of a draft tube spouted bed
Authors: Khoe G. K. , Van Brakel J. 
Published: March 2009

AbstractUsing the results of earlier work on the flow pattern of gas and solids in a draft‐tube spouted bed, the drying characteristics of such a spouted bed are discussed. Paddy (unpeeled rice) was dried in a 30 cm bed with a 5.5 cm draft tube and temperatures and moisture content of solid and gas phase were measured as a function of drying time at various points in the system. It appears that the (constant) drying rate is determined by the heat transfer in the recirculation zone (just above the air inlet) and in the draft tube. After the short and rapid heating in the tube, the temperature and moisture gradients in the particle equilibrate in the annulus. It is concluded that a draft‐tube spouted bed is a promising dryer design for heat‐sensitive particles with slow intra‐particle mass transfer coefficients.
Laminar natural convection heat transfer from a slender vertical cone to a power‐law fluid
Authors: Shenoy A. V. 
Published: March 2009

AbstractA theoretical analysis of laminar natural convection heat transfer from a slender vertical cone to a power‐law fluid has been done by the approximate integral method. Assuming unequal thermal and momentum boundary layer thicknesses, and using the appropriate boundary and compatibility conditions, a “similar” solution of the boundary layer equations has been obtained for high Prandtl numbers. Due to lack of experimental data for power‐law fluids, a comparison of the predictions of the present analysis has been done with the experimental data available for Newtonian fluids and good agreement has been found.
The production of the antibiotic patulin in a three phase fluidized bed reactor: II. Longevity of the biocatalyst
Authors: Berk Dimitrios , Behie Leo A. , Jones Alan , Lesser Barry H. , Maurice Gaucher G. 
Published: March 2009

AbstractThe longevity of the enzyme system for the production of the antibiotic patulin by immobilized Penicillium urticae cells was studied in a three phase fluidized bed reactor. Calculation of the global rate of patulin production indicated that, if the cells were not allowed to grow, the production of patulin gradually declined and stopped at 320 h. Intermittent pulse additions of nutrients stimulated the slow growth of the cells and resulted in an extended production time of 525 h. This long term production was the result of the formation of new cells rather than the maintenance of the original ones.
Model discrimination: Posterior probabilities
Authors: Dunne Adrian , Lacey Laurence 
Published: March 2009

AbstractExpressions were derived for the computation of regression model posterior probabilities under a number of assumptions regarding the form of the uniform parameter prior probability density function. It was demonstrated that some of these forms may lead to a bias in the model posterior probabilities. The variance known and unknown situations were considered under both homoscedastic and heteroscedastic conditions. Bias of the model posterior probabilities may partly explain the unstable behaviour reported by previous workers.
Visualization of flow patterns in axial flow between horizontal coaxial rotating cylinders
Authors: Gu Z. H. , Fahidy T. Z. 
Published: March 2009

AbstractThe structure of Taylor vortices in the annulus of coaxial horizontal rotating cylinders with and without axial flow was studied by a flow visualization technique based on the colour change of analytical indicators. Flow interaction effects can be characterized by three parameters whose numerical values are obtained from photographs and super 8 mm film strips.