bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of oxygen supply condition and specific biofilm interfacial area on phenol removal rate in a three‐phase fluidized bed bioreactor
Authors: Hirata Akira , Meutia Ami Aminah , Osawa Makoto , Arai Manabu , Tsuneda Satoshi 
Published: March 2009

AbstractThe effects of oxygen supply conditions and specific biofilm interfacial area on the phenol removal rate in a three‐phase fluidized bed bioreactor were evaluated. The experimental data were well‐explained by the semi‐theoretical equation based on the assumption that the reaction rate follows first‐order reaction kinetics with respect to oxygen and zero‐order one with respect to phenol. Two cases, biological reaction as rate‐controlling step and oxygen absorption as rate‐controlling step, were both explicable by this semi‐theoretical equation. The maximum volumetric phenol removal rate was 27.4 kg·m−3·d−1.
Mechanism of selenium sorption by activated carbon
Authors: Jadhav Raja A. , Agnihotri Rajeev , Gupta Himanshu , Fan Liang‐Shih 
Published: March 2009

AbstractSelenium, along with mercury and halides, represents one of the most volatile trace metallic emissions from coal‐fired combustors and utility boilers. This study investigates the potential of activated carbon in capturing gas phase selenium species in the low temperature range (125°C to 250°C) and elucidates the mechanism of interaction between selenium species and activated carbon. Selenium dioxide is chosen as the representative selenium species and experimental investigations are carried out in a differential bed reactor to illustrate the mechanism of SeO2 and carbon Interaction, Activated carbons with different structural properties are studied as adsorbents for selenium dioxide capture at low temperature. The capture mechanism is found to involve both physical and chemical adsorption in the low temperature range. At 125°C, about 1.5 wt% of selenium is captured at equillbrium. Carbon surface analyses and XPS studies confirm the presence of both elemental and oxide forms of selenium on the surface suggesting partial reduction of selenium dioxide to elemental selenium at carbon surface.
Modelling and analysis of membrane‐attached biofilms
Authors: Nicolella Cristiano , Pavasant Prasert , Livingston Andrew G. 
Published: March 2009

AbstractThe theory of diffusion and reaction has been applied to describe mass transfer and reaction phenomena in membrane‐attached biofilms (MABs) growing in extractive membrane bioreactors (EMBs), and to establish the rate‐limiting mechanisms in these systems. The model formulated accounts for substrate counter‐diffusion and two‐limiting‐substrate reaction within the biofilm. Model simulations are compared to experimental data obtained in a lab‐scale EMB and a simple case study is considered to show how MABs affect performance of EMBs. It is found that the organic substrate flux across the membrane is strongly affected by MABs, which constitute an additional resistance to mass transfer and in most cases reduce the flux across the membrane. As a result of the investigation, it is concluded that the decrease of flux in the presence of MABs, observed experimentally and predicted theoretically, is dominated by the resistance to organic substrate transfer caused by the biofilm.
Mixing behaviour of solids in multiple spouted beds
Authors: Saidutta M. B. , Murthy D. V. R. 
Published: March 2009

AbstractStimulus response experiments are conducted in four different rectangular columns having two and three spout cells. A pink‐coloured polymer material is used as bed material with ambient air as the spouting fluid. A pulse input of dark blue colour polymer material is used as the stimulus, when the column is operating under steady flow conditions, and the response measured. A mathematical model “plug flow‐mixed flow in series” is used to fit the experimental data and the model parameters are evaluated.
Coal combustion in O2/CO2 mixtures compared with air
Authors: Croiset Eric , Thambimuthu Kelly , Palmer Allan 
Published: March 2009

AbstractAs part of CO2 abatement strategies for climate change, we are investigating coal combusion behaviour in various O2/CO2 mixtures and in air. The goal is to simulate conditions of coal combustion with flue gas recirculation in order to maximize the CO2 concentration in the flue gas prior to its recovery. A western Canadian sub‐bituminous coal and a U.S. eastern bituminous coal were investigated. Thermal input was set at 0.21 MW with a flue gas oxygen concentration of 5 vol%. Experiments were done using various O2/CO2 mixtures and air. The oxygen concentration ranged from 21% to 42%. Up to 95% CO2 concentrations were achieved in the flue gas. This paper describes experimental results in terms of flame temperatures and pollutant emissions (NOx', SO2 and CO).
Beneficial combination of wet oxidation, membrane separation and biodegradation processes for treatment of polymer processing wastewaters
Authors: Mantzavinos Dionissios , Hellenbrand Rolf , Livingston Andrew G. , Metcalfe Ian S. 
Published: March 2009

AbstractThe treatment of a model wastewater containing polyethylene glycol of molecular weight (MW) 10 000 by means of combined chemical oxidative pretreatment, membrane separation and biological post‐treatment was investigated. Wet oxidation was employed as a chemical pretreatment process to convert the original, high MW polymer to lower MW compounds in an attempt to improve the biotreatability of the waste‐water. The partially oxidized effluents formed during wet oxidation at temperatures up to 403 K were separated by nanofiltration where larger molecules were recycled into the wet oxidation reactor, while the permeate leaving the filtration step was treated biologically. At a biological residence time (τB) of 12 h and 3 h, the resulting total organic carbon (TOC) removal in the biological step was as high as 94% and 87%, respectively. Conversely, a continuous aerobic biological process was found inadequate to completely mineralize the original wastewater, since at τb of 96 h only about 60% to 70% TOC removal was achieved, while at τb of 12 h the original wastewater was practically non‐biockgradable.
Experimental studies of liquid flow maldistribution in a random packed column
Authors: Yin Fuhe , Wang Zhongcheng , Afacan Artin , Nandakumar Krishnaswamy , Chuang Karl T. 
Published: March 2009

AbstractLiquid flow distribution has been a major concern when scaling up random packed columns. This study concerns the measurements of liquid flow distribution in a large scale column packed with 25.4 mm stainless steel Pall rings. The liquid flow distribution was studied with packed bed height from 0.9 to 3.5 m, liquid flow rate from 2.91 to 6.66 kg/m2·s, and gas flow rate from 0 to 3.0 kg/m2·s. In addition, three systems, water/air, aqueous detergent solution/air and Isopar/air, were used to study the effect of liquid physical properties on liquid flow distribution, and two different liquid distributors were employed to test the effect of liquid distributor design. It was found that liquid flow distribution was strongly influenced by liquid distributor design, packed bed height, gas flow rate and liquid viscosity, slightly influenced by liquid flow rate, but not by liquid surface tension.
Methods for measuring the concentrations of SO2, and of gaseous reduced sulphur compounds in the combustion chamber of a circulating fluidized bed boiler
Authors: Fernández Maríaa Joséa , Kassman Håkan , Lyngfelt Anders 
Published: March 2009

AbstractThe present work was aimed at developing and improving methods for measurement of gaseous sulphur compounds in the combustion chamber of a fluidized bed boiler (FBB). The sampling of SO2 was improved by removing NH3 and H2O with a sorbent immediately after the probe. The concentration of reduced sulphur species was determined by means of two conventional SO2 analyzers and an intermediate converter, where the reduced species are oxidized to SO2. Gas phase sulphides were also sampled with a gas quenching probe by means of a basic solution which was subsequently analysed by wet chemistry. The methods were tested during coal combustion in a 12 MW circulating FBB without limestone for two cases of air‐staging.
Ventilation design of industrial premises through CFD modelling
Authors: Rota Renato , Canossa Luca , Nano Giuseppe 
Published: March 2009

AbstractThis work investigates a general ventilation system for reducing the health hazard in industrial premises. Several tests carried out in a laboratory mock‐up have been used to validate the reliability of a general‐purpose computational fluid dynamic model. The same model has been also used to compare the efficiency of different ventilation systems. This clearly indicated the different health hazard related to each configuration, thus allowing one to identify the configuration leading to the lower contamination in the breathing zone.
Determination of the activation energy and intrinsic rate constant of methane gas hydrate decomposition
Authors: Clarke Matthew , Bishnoi P. Raj 
Published: March 2009

AbstractExperimental data on the kinetics of methane gas hydrate decomposition are reported. The isothermal/isobaric semi‐batch stirred‐tank reactor, used by Kim et al. (1987), was modified to include an on‐line particle size analyzer. The experiments were conducted at temperatures ranging from 274.65 K to 281.15 K and at pressures between 3.1 and 6.1 MPa. The model of Clarke and Bishnoi (1999, 2000) was used to determine the intrinsic rate constant. It was found that the activation energy for methane hydrate decomposition is 81 kJ/mol and the intrinsic rate constant of decomposition is 3.6 × 104 mol/m2 Pa.s.
Flow of solids in an interconnected fluidized beds system investigated using positron emission particle tracking
Authors: Stellema Cornelis S. , Gerritsen Albert W. , Kolar Zvonimir I. , de Goeij Jeroen J. M. , Van Den Bleek Cornelis M. 
Published: March 2009

AbstractThe technique of Positron Emission Particle Tracking (PEPT) is applied to analyse non‐intrusively solids flow in a laboratory scale Interconnected Fluidized Beds system. It is shown that, with a high performance tracking system, it is possible to extract from the data not only the Eulerian ensemble average velocity field, but also to reconstruct density profiles and to calculate mass flows in a solids circulation system. The most interesting flow characteristics inside the Interconnected Fluidized Bed system are highlighted. Although the data analysis is largely Eulerian, a first approach to a Lagrangian analysis has been performed through the computation of velocity autocorrelation functions. Characteristic frequencies of the solids movement could not be identified, but the velocity autocorrelations did provide insight in the dynamics of the solids movement.
Centrifugal degassing of highly viscous newtonian liquids
Authors: Kiljański Tomasz , Dziubiński Marek 
Published: March 2009

AbstractThe movement of gas bubbles in a Newtonian liquid under centrifugal forces was considered. Taking into account wall effects and the increase of bubble diameter during the movement caused by pressure decrease, equations for the bubble movement time in the case of entirely free and immobile bubble surface were derived. Experiments on centrifuging air bubbles showed that in the centrifuge the bubble retained a free surface even at much smaller diameters than under gravity forces. A dimensionless bubble diameter was defined and its critical value above which bubbles behaved as free ones was evaluated.
The fate of methane in a claus plant reaction furnace
Authors: Chin Hilton S. F. , Karan Kunal , Mehrotra Anil K. , Behie Leo A. 
Published: March 2009

AbstractExperimental kinetic data are reported for key side reactions occurring in the front end [i. e. the reaction furnace (RF) and the waste heat boiler (WHB)] of modified Claus plants used for sulfur recovery from the sour gases evolved in the treatment of natural gas. An extensive experimental study was conducted in a high temperature tubular reactor system for two important homogenous gas‐phase reactions. Firstly, experiments were carried out to study the oxidation of hydrogen sulfide and methane mixtures in the presence of oxygen. Secondly, the reaction between methane and sulfur dioxide was investigated experimentally. These results showed that methane was much less competitive for oxygen than hydrogen sulfide. Hence, in a partially oxidizing environment of a RF, data showed that methane reacted significantly with other major sulfur containing species, as secondary reactions, to form COS and especially CS2. This is highly problematic from an environmental point of view.
A simplified mechanistic analysis of the hydration of magnesia
Authors: Birchal V. S. , Rocha S. D. F. , Mansur M. B. , Ciminelli V. S. T. 
Published: March 2009

AbstractThe kinetics of the hydration of magnesia to produce magnesium hydroxide is described by a kinetic model with no diffusive contribution, including an additional resistance to the reactive flux due to the transient variation of the porosity of the material during reaction. The proposed model has been applied to data from the literature and obtained by hydration of MgO samples with distinct physical characteristics. The model describes well the mechanism of hydration of powder and single crystal MgO in liquid and vapour water with temperatures varying from 35°C to 200°C.
Catalysis assisted plasma decomposition of benzene using dielectric barrier discharge
Authors: Sekiguchi Hidetoshi 
Published: March 2009

AbstractAtmospheric non‐thermal plasma generated by dielectric barrier discharge was applied to decompose benzene with a sheet type catalyst of platinum supported by alumina. The experimental results indicated that an enhancement of the decomposition by the catalyst was achieved at low concentration of benzene. Ozone produced in the plasma seemed not to contribute to the decomposition. The deactivation of the catalyst was also observed due to decomposition products such as CO and a solid deposit. However a heating treatment could regenerate the catalyst. The results suggested the plasma‐catalyst hybrid reactor was the effective method to solve volatile organic compound (VOCs) problem.
Extension to mixtures of two robust hard‐sphere equations of state satisfying the ordered close‐packed limit
Authors: Ghotbi Cyrus , Vera Juan H. 
Published: March 2009

AbstractTwo new hard‐sphere EOS are proposed and tested using the same attractive potential terms used by the SAFT EOS. Generalized expressions for the pair RDF at contact value, the compressibility factor, and the excess chemical potentials have been derived. Extension to mixtures is tested using three mixing rules for multicomponent hard‐sphere fluids. The proposed EOS combined with the Santos et al. and the Barrio‐Solana mixing rules reproduced the compressibility factors and the excess chemical potentials more accurately than the Boublik‐Mansoori‐Camahan‐Starling‐Leland (BMCSL) EOS. However the pair RDF at contact value had larger deviations than those obtained with the BMCSL EOS. The combination of the proposed equations and the Barrio‐Solana mixing rule gave an accurate reproduction of the compressibility factor for binary hard‐sphere fluids with high diameter ratio even in the low concentration regions of the larger spheres.
Right Cardiac Thrombus in Transit Among Patients with Pulmonary Thromboemboli
Authors: Mollazadeh Reza , Ali Ostovan Mohammad , Abdi Ardekani Ali Reza 
Published: March 2009

AbstractBackgroundThis study was designed to investigate the prevalence, clinical and laboratory findings, and short‐term prognostic significance of mobile right cardiac thrombus (MRCT) among patients with pulmonary thromboembolism (PTE).MethodsFrom January 2004 to November 2006, 12 of 100 patients admitted with a diagnosis of PTE had an MRCT. Diagnosis of in‐transit right‐sided thrombi was made when a wormlike elongated mass was detected. The primary end point was comparison of the mortality rate of MRCT (+) patients with that of MRCT (−) patients for an average of 8 months of follow‐up. The secondary end points were comparison of clinical and laboratory data between these 2 groups.ResultsAll MRCT (+) patients but 1 had dyspnea, but just 2 patients had syncope during exertion. The most frequent electrocardiographic finding was T inversion in leads V1–V3 (75%). All 6 of the MRCT (+) patients who had a cardiac arrest in the hospital died in the hospital. In comparison, of the 88 MRCT (−) patients, 12 had a cardiorespiratory arrest, 4 of whom survived (hospital mortality rate of 50% versus 9%, respectively).ConclusionsIt seems that the presence of MRCT has prognostic significance, predicting a higher‐than‐average mortality rate. Copyright © 2009 Wiley Periodicals, Inc.
What explains the extent and content of social and environmental disclosures on corporate websites: a study of social and environmental reporting in Swedish listed corporations
Authors: Tagesson Torbjörn , Blank Veronica , Broberg Pernilla , Collin Sven‐Olof 
Published: March 2009

AbstractThe demand for information and transparency from corporations has increased over the last few years. Today, there are other information dissemination channels besides annual financial statements. One important channel is the Internet. The aim of this study is to explain the extent and content of social disclosure information on corporations' websites. The empirical data in this study is based on annual financial statements and such websites. A multi‐theoretical framework is used in order to explain the extent and content of social disclosures on corporate websites. The findings support the positive correlation of size and profitability with the content of social disclosure information on these websites. In general, State‐owned corporations disclose more social information on their websites than privately owned corporations do. There are significant differences between different industries. This is true regarding not only the extent of social disclosures, but also their content. Copyright © 2009 John Wiley & Sons, Ltd and ERP Environment.
Prolonged exclusive breastfeeding reduces autoimmune diabetes incidence and increases regulatory T‐cell frequency in bio‐breeding diabetes‐prone rats
Authors: Brugman S. , Visser J. T. J. , Hillebrands J. L. , Bos N. A. , Rozing J. 
Published: March 2009

AbstractBackgroundPreviously, we reported that exclusive breastfeeding delayed and partially protected bio‐breeding diabetes‐prone (BBDP) rats from spontaneous autoimmune diabetes development. To investigate whether this protection results from modulation of the (mucosal) immune system, the present study was designed to analyse the effect of nutrition early in life on the immune status of BBDP rats.MethodsThe breastfeeding period of BBDP pups was extended or not, while allowing half of the pups to eat during that period whereas the other half received only breast milk. Cytokine profiles as well as naturally occurring regulatory T‐cell frequencies were measured over time in the mesenteric lymph nodes (MLNs) and spleen.ResultsProlonged exclusive breastfeeding partially protects against autoimmune diabetes development and resulted in elevated levels of natural regulatory T cells (CD4+ CD25+ FoxP3+) in MLNs and spleen directly after weaning and throughout life. Stimulation of MLN cells from rats that ingested solid food during the nursing period showed massive secretion of interferon gamma (IFN‐γ), interleukin (IL)‐4 and IL‐10, whereas MLN cells from exclusive breastfed rats did not. In contrast, transforming growth factor beta (TGF‐ß) was secreted equally by all groups.ConclusionsProlonged exclusive breastfeeding partially protects BBDP rats from autoimmune diabetes development. Interestingly, ingestion of solid food during the weaning period completely abolishes this protective effect. The protective effect of exclusive breastfeeding correlates with higher levels of naturally occurring regulatory T cells throughout life and low cytokine secretion at weaning. Copyright © 2009 John Wiley & Sons, Ltd.
Mitotic patterns in the migrating lateral line cells of zebrafish embryos
Authors: Laguerre Laurent , Ghysen Alain , Dambly‐Chaudière Christine 
Published: March 2009

AbstractThe sense organs of the posterior lateral line system (neuromasts) are formed by a migrating primordium. In zebrafish, the primordium comprises approximately 100 cells at the onset of migration, and has deposited approximately 300 cells by the end of the process. Here, we report localized phases of mitotic activity and of mitotic quiescence within the migrating primordium. Quiescence in the leading region seems associated to the formation of a new prospective neuromast, whereas quiescence in the trailing region follows a wave of mitoses that synchronize trailing cells in G0/G1 phase, anticipating neuromast differentiation. Manipulating the size of the primordium does not lead to changes in the rate of cell proliferation. We also show that two mitoses often take place nearly synchronously in adjacent cells, suggestive of a determinate lineage. We conclude that proliferation in the migrating primordium follows a stereotyped pattern that closely anticipates the normal development of the system. Developmental Dynamics 238:1042–1051, 2009. © 2009 Wiley‐Liss, Inc.
The Synthesis of New HetPHOX Ligands and Their Application to the Intermolecular Asymmetric Heck Reaction
Authors: Fitzpatrick Martin O. , Muller‐Bunz Helge , Guiry Patrick J. 
Published: March 2009

AbstractThe synthesis of six members of the HetPHOX ligand class and the application of palladium complexes of these ligands to the intermolecular asymmetric Heck reaction is described. The tert‐leucinol‐derived ligands proved the most enantioselective, with palladium complexes of these ligands affording ee values of up to 96, 95 and 94 % in the phenylation, cyclohexenylation and naphthylation, respectively, of 2,3‐dihydrofuran. As an aid to the explanation of the observed selectivity a palladium complex of the most enantioselective ligand was prepared and an X‐ray crystal structure obtained. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
On the effect of prior assumptions in Bayesian model averaging with applications to growth regression
Authors: Ley Eduardo , Steel Mark F.J. 
Published: March 2009

AbstractWe consider the problem of variable selection in linear regression models. Bayesian model averaging has become an important tool in empirical settings with large numbers of potential regressors and relatively limited numbers of observations. We examine the effect of a variety of prior assumptions on the inference concerning model size, posterior inclusion probabilities of regressors and on predictive performance. We illustrate these issues in the context of cross‐country growth regressions using three datasets with 41–67 potential drivers of growth and 72–93 observations. Finally, we recommend priors for use in this and related contexts. Copyright © 2009 John Wiley & Sons, Ltd.