bluuebunny/crossref_metadata_2025_split huggingface dataset:
Kinetics of Catalytic Ozonation of Methyl tert‐Butyl Ether in the Presence of Perfluorooctyl Alumina
Authors: Ebadi A. , Mohammadzadeh J. S. , Shafiei S. 
Published: April 2009

AbstractIn this work, the kinetics of heterogeneous ozonation of methyl tert‐butyl ether (MTBE) in the presence of perfluorooctyl alumina (PFOAL) catalysts is presented. Activity of the PFOAL catalysts in ozonation reactions of MTBE was studied in a batch reactor over the temperature range of 25 to 40 °C. The results show that PFOAL is an effective catalyst for enhancing the molecular mechanism of ozone reactions. For a catalyst concentration of 5 g/L, the contribution of the rate of heterogeneous catalytic reaction in the total reaction rate is about 50 %, 75 %, and 85 % at the reaction temperatures of 25 °C, 30 °C, and 40 °C, respectively. Kinetic studies showed that the chemical reaction of ozone and MTBE is the controlling step in this catalytic system. The quasi‐homogeneous kinetic model proved to be an appropriate approach in modeling the heterogeneous reaction of ozone with MTBE on PFOAL catalysts.
Hydrophilicity Enhancement of High‐Density Polyethylene Film by Ozonation
Authors: Gu H. , Wu J. , Doan H. 
Published: April 2009

AbstractHigh‐density polyethylene (HDPE) films were ozonated in the gas phase and in distilled water, respectively, to improve their surface hydrophilicity. The efficiency of ozonation conducted in the gaseous and aqueous phases was compared. The results indicated that the aqueous ozonation was more effective than its gaseous counterpart in terms of peroxide generation. The results also showed that the concentration of peroxides generated on the film surfaces increased with the applied ozone dose and ozonation time in both phases. It was found that the peroxides generated by aqueous ozonation were accessible to monomers for graft polymerization. The hydrophilicity of the HDPE films was significantly improved by graft polymerization of acrylamide (AAm) initiated by the peroxides. The contact angle reduction from 74.9° to 38.6° indicated the successful graft polymerization. The successful graft polymerization of AAm was further confirmed by the formation of new peaks corresponding to amide groups in FTIR spectra and by scanning electron microscope images.
Fault Detection and Diagnosis in a Sour Gas Absorption Column Using Neural Networks
Authors: Behbahani R. M. , Jazayeri‐Rad H. , Hajmirzaee S. 
Published: April 2009

AbstractProcess fault detection and diagnosis is an important problem in plant control at the supervisory level. It is the central component of abnormal event management which has attracted a lot of attention recently. In this study, the use of artificial neural networks (ANN) for fault detection is explored. An ANN can represent nonlinear and complex relations between its inputs (sensor measurements) and outputs (faults). As a test case, absorption of CO2 gas in monoethanolamine (MEA) by a pilot plant called “automatic absorption and stripping pilot plant” is studied. For detecting and diagnosis of faults, variations in feed rate, feed composition, liquid absorber rate and composition are imposed onto the plant. The faults in this process influence variables such as the composition of absorbed gas (CO2) and temperature and pressure drop of the column. The CO2 concentration in the product should not exceed a certain limit. By selecting a proper architecture for the network (5‐9‐10), it is possible to detect the faults accurately. The network is trained using the back propagation method. The developed fault diagnosis algorithm is tested using data that has not been seen by the network.
Multiphase CFD Simulation of a Solid Bowl Centrifuge
Authors: Romaní Fernández X. , Nirschl H. 
Published: April 2009

AbstractThis study presents some results from the numerical simulation of the flow in an industrial solid bowl centrifuge used for particle separation in industrial fluid processing. The computational fluid dynamics (CFD) software Fluent was used to simulate this multiphase flow. Simplified two‐dimensional and three‐dimensional geometries were built and meshed from the real centrifuge geometry. The CFD results show a boundary layer of axially fast moving fluid at the gas‐liquid interface. Below this layer there is a thin recirculation. The obtained tangential velocity values are lower than the ones for the rigid‐body motion. Also, the trajectories of the solid particles are evaluated.
CO2 Absorption into Aqueous Solutions of Monoethanolamine, Methyldiethanolamine, Piperazine and their Blends
Authors: Dubois L. , Thomas D. 
Published: April 2009

AbstractThe removal of carbon dioxide from industrial gases, e.g. in thermal power stations to meet the discharge limits for CO2 in flue gases, is usually achieved with a reactive absorption technique using aqueous solutions of alkanolamines. From the absorption performance point of view, primary and secondary amines are preferred. However, in case the costs of the solvent regeneration are also taken into account, tertiary amines are much more attractive. In order to combine the specific advantages of tertiary and primary/secondary alkanolamines, both types of solvents are mixed. In this paper, mixtures of monoethanolamine and methyldiethanolamine with piperazine as absorption activator are experimentally compared with respect to CO2 removal performances at 25 °C. The absorption process in a special packed column has also been simulated with the use of published data on reaction kinetics, physicochemical properties (densities, viscosities, diffusivities, Henry coefficients) of the CO2‐amines systems, including experimentally determined hydrodynamic and mass transfer characteristics of the CO2 scrubber.
Experimental and Theoretical Investigation of Double Gas Hydrate Formation in the Presence or Absence of Kinetic Inhibitors in a Flow Mini‐Loop Apparatus
Authors: Talaghat M. R. , Esmaeilzadeh F. , Fathikaljahi J. 
Published: April 2009

AbstractDouble gas hydrate formation in the presence or absence of kinetic inhibitors in a flow mini‐loop apparatus was investigated. For the prediction of the gas consumption rate during hydrate formation in this system, the rate equation based on the Kashchiev and Firoozabadi model for simple gas hydrate formation in a batch system was developed for double gas hydrate formation in a flow mini‐loop apparatus. To complete the theoretical evaluation of gas hydrate formation through the mini‐loop apparatus in the presence or absence of kinetic hydrate inhibitors (KHI), a laboratory flow mini‐loop apparatus was set up to measure the induction time for hydrate formation and the uptake rate when a gaseous mixture (such as 75 % C1/25 % C3, 25 % C1/75 % C3, 75 % C1/25 % i‐C4, and 25 % C1/75 % i‐C4) is contacted with water containing or not containing dissolved inhibitor under suitable temperature and pressure conditions. In each experiment, a water blend saturated with gas mixture was circulated up to the required pressure. The pressure was maintained at a constant value during the experimental runs by means of a required gas mixture make‐up. The effect of pressure on gas consumption during hydrate formation was investigated in the presence or absence of polyvinylpyrrolidone (PVP) and L‐tyrosine as kinetic inhibitors at various concentrations. A good agreement was found between the predicted and experimental data in the presence or absence of KHI. The total average absolute deviation percents between the experimental and predicted values of gas consumption were found to be 16.4 and 17.5 % for the double gas hydrate formation in the presence or absence of the kinetic inhibitors, respectively.
Migration of Potassium in an Fe2O3/H‐ZSM‐5 Composite Catalyst
Authors: Gwagwa X. Y. , van Steen E. 
Published: April 2009

AbstractThe migration of potassium in an iron/H‐ZSM‐5 bifunctional system was investigated by pressing K/Fe2O3 and H‐ZSM‐5 in a pellet using 2 t of pressure. These pellets were heated at 350 °C in air for a number of days. Migration of potassium was visualized using energy‐dispersive X‐ray profiling. The distribution of potassium in the Fe2O3 phase and the H‐ZSM‐5 phase was approximately constant, with a step change over the phase boundary. The step change varied as a function of the heating time. The amount of potassium migrated from the Fe2O3 phase to the H‐ZSM‐5 phase was quantified using NH3‐TPD. It is shown that an equilibrium distribution between potassium in the Fe2O3 phase and the H‐ZSM‐5 phase is obtained after ca. 7 days of heating.
The effect of structural redundancy in validation sets on virtual screening performance
Authors: Clark Robert D. , Shepphird Jennifer K. , Holliday John 
Published: April 2009

AbstractThe performance of a classification model is often assessed in terms of how well it separates a set of known observations into appropriate classes. If the validation sets used for such analyses are redundant due to bias in sampling, the relevance of the conclusions drawn to prospective work in which new kinds of positives are sought may be compromised. In the case of the various virtual screening techniques used in modern drug discovery, such bias generally appears as over‐representation of particular structural subclasses in the test set. We show how clustering by substructural similarity, followed by applying arithmetic and harmonic weighting schemes to receiver operating characteristic (ROC) curves, can be used to identify validation sets that are biased due to such redundancies. This can be accomplished qualitatively by direct examination or quantitatively by comparing the areas under the respective linear or semilog curves (AUCs or pAUCs). Copyright © 2009 John Wiley & Sons, Ltd.
Racemization of Alcohols Catalyzed by [RuCl(CO)2(η5‐pentaphenylcyclopentadienyl)]—Mechanistic Insights from Theoretical Modeling
Authors: Nyhlén Jonas , Privalov Timofei , Bäckvall Jan‐E. 
Published: April 2009

AbstractWhich mechanism? Dissociation of a CO ligand from alkoxide complex 1 to give intermediate 2 seems to be a viable pathway for racemization according to DFT calculations. The highest Gibbs free energy barrier is 22.6 kcal mol−1 for this pathway. Very fast alkoxide exchange can occur in 2 with essentially no barrier. The calculations indicate an alternative low‐energy pathway for alkoxide exchange between 1 and 1′ without CO dissociation with a barrier of only 13 kcal mol−1.magnified imageTwo possible pathways of inner‐sphere racemization of sec‐alcohols by using the [RuCl(CO)2(η5‐pentaphenylcyclopentadienyl)] catalyst (1) have been thoroughly investigated by means of density function calculations. To be able to racemize alcohols, catalyst 1 needs to have a free coordination site on the metal. This can be achieved either by a η5→η3 ring slippage or by dissociation of a carbon monoxide (CO) ligand. The η5→η3 ring‐slip pathway was found to have a high potential energy barrier, 42 kcal mol−1, which can be explained by steric congestion in the transition state. On the other hand, CO dissociation to give a 16‐electron complex has a barrier of only 22.6 kcal mol−1. We have computationally discovered a mechanism involving CO participation that does not require η5→η3 ring slippage. The key features of this mechanism are 1) CO‐assisted exchange of chloride for alkoxide, 2) alcohol–alkoxide exchange, and 3) generation of an active 16‐electron complex through CO dissociation with subsequent β‐hydride elimination as the racemization step. We have found a low‐energy pathway for reaction of 1 with potassium tert‐butoxide and a pathway for fast alkoxide exchange with interaction between the incoming/leaving alcohol and one of the two CO ligands. We predict that dissociation of a Ru‐bound CO ligand does not occur in these exchange reactions. Dissociation of one of the two Ru‐bound CO ligands has been found necessary only at a later stage of the reaction. Though this barrier is still quite high, our results indicate that it is not necessary to cross the CO dissociation barrier for the racemization of each new alcohol. Thus, the dissociation of a CO ligand is interpreted as a rate‐limiting reaction step in order to create a catalytically active 16‐electron complex.
Chiral Cobalt‐Catalyzed Enantiomer‐Differentiating Oxidation of Racemic Benzoins by Using Molecular Oxygen as Stoichiometric Oxidant
Authors: Kumar Alamsetti Santosh , Muthupandi Pandi , Sekar Govindasamy 
Published: April 2009

AbstractAn efficient enantioselective oxidative reaction catalyzed by a chiral cobalt complex has been developed by using molecular oxygen as the stoichiometric oxidant (see scheme). The very mild reaction conditions of the catalytic system provide access to a wide range of benzoins (α‐hydroxyketones) in high yield and excellent enantioselectivity (s (kf/ks) up to 47). This method is very versatile because the sole by‐product of our oxidation process is water, which makes our system more eco‐friendly and green.magnified image
ChemInform Abstract: Structural Evolution of Doped Gold Clusters: MAu‐x (M: Si, Ge, Sn; x = 5—8).
Authors: Pal Rhitankar , Wang Lei‐Ming , Huang Wei , Wang Lai‐Sheng , Zeng Xiao Cheng 
Published: April 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Synthesis and Structure of a New Mixed‐Metal Disulfide Thiophosphate, Nb0.44Ta0.56PS6.
Authors: Yun Hoseop 
Published: April 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Rare Earth‐Rich Cadmium Compounds Ln23T7Cd4 (T: Co, Ni, Ru, Rh, Ir, Pt).
Authors: Tappe Frank , Poettgen Rainer 
Published: April 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Synthesis and Characterization of Framework‐Substituted Cs8Na16Cu5Ge131.
Authors: Beekman M. , Kaduk J. A. , Gryko J. , Wong‐Ng W. , Shapiro A. , Nolas G. S. 
Published: April 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Thermodynamic Properties of Nd1+xBa2‐xCu3Oy Compounds and Their Application for Optimizing the Synthesis of Superconducting Materials.
Authors: Zelenina Ludmila N. , Chusova Tamara P. , Matskevich Nata I. , Naumov Victor N. , Stenin Yuri G. , Krabbes Gernot 
Published: April 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: The Isothermal Section of the Gd—Ni—V Ternary System at 773 K
Authors: Zhong Yan , Zhou Huaiying , Yao Qingrong , Tang Chengying , Zhou R. P. 
Published: April 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Mn3O4 Doped with Nano‐NaBiO3: A High Capacity Cathode Material for Alkaline Secondary Batteries.
Authors: Pan Junqing , Sun Yanzhi , Wang Zihao , Wan Pingyu , Fan Maohong 
Published: April 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: 6Li MAS NMR Investigation of Electrochemical Lithiation of RuO2: Evidence for an Interfacial Storage Mechanism.
Authors: Bekaert Emilie , Balaya Palani , Murugavel Sevi , Maier Joachim , Menetrier Michel 
Published: April 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Switching Off Hydrogen Peroxide Hydrogenation in the Direct Synthesis Process.
Authors: Edwards Jennifer K. , Solsona Benjamin , Ntainjua N Edwin , Carley Albert F. , Herzing Andrew A. , Kiely Christopher J. , Hutchings Graham J. 
Published: April 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Photochemistry of SO2/Cl2/O2 Gas Mixtures: Synthesis of the New Peroxide ClSO2OOSO2Cl.
Authors: Romano Rosana M. , Della Vedova Carlos O. , Beckers Helmut , Willner Helge 
Published: April 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: A New Sodium Borate: Na[B6O8(OH)3] ·6H2O·H3BO3.
Authors: Koese Dursun Ali , Zuemreoglu‐Karan Birguel , Hoekelek Tuncer , Sahin Ertan 
Published: April 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Fluoride Containing Guest Species in Alumosilicates: Tetrafluoroborate in the Sodalite Na8Al6Si6O24 (BF4)2.
Authors: Lezhnina Marina M. , Jordan Edgar , Klimin Sergej A. , Loens Juergen , Koller Hubert , Mavrin Boris N. , Kynast Ulrich 
Published: April 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Rare Earth Metal Disulfides — Syntheses and Crystal Structures of α‐CeS2, α‐NdS2, β‐LaS2, β‐CeS2 and β‐PrS2.
Authors: Schleid Thomas , Lauxmann Petra , Graf Christian , Bartsch Christian , Doert Thomas 
Published: April 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Extended Members of the Layered Rare‐Earth Hydroxide Family, RE2(OH)5NO3·nH2O (RE: Sm, Eu, and Gd): Synthesis and Anion‐Exchange Behavior.
Authors: Lee Kyung‐Hee , Byeon Song‐Ho 
Published: April 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: The Versatility of Solid‐State Metathesis Reactions: From Rare Earth Fluorides to Carbodiimides.
Authors: Unverfehrt Leonid , Glaser Jochen , Stroebele Markus , Tragl Sonja , Gibson Katharina , Meyer H.‐Juergen 
Published: April 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: CeAsSe — Synthesis, Crystal Structure, and Physical Properties.
Authors: Schlechte A. , Niewa R. , Prots Yu. , Schnelle W. , Schmidt M. , Kniep R. 
Published: April 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Solvothermal Synthesis, Crystal Structure and Properties of the First Organic‐Templated Holmium Sulfate [C2N2H10]3 [Ho2(SO4)6·2H2O].
Authors: Zhou Wanli , Chen Qi , Zhu Dunru , Xu Yan 
Published: April 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Crystal Growth of Bismuth(V) Oxides from Hydroxide Fluxes.
Authors: Bharathy M. , Khalsa Hargobind S. , Smith Mark D. , zur Loye H.‐C. 
Published: April 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Condensation Products of 1‐Aryl‐4‐hydrazinocarbonyl‐2‐pyrrolidinones with Diketones.
Authors: Mickevicius V. , Vaickelioniene R. 
Published: April 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Benzylic Carbon Oxidation by an in situ Formed o‐Iodoxybenzoic Acid (IBX) Derivative.
Authors: Ojha Lawanya R. , Kudugunti Shashi , Maddukuri Padma P. , Kommareddy Amitha , Gunna Meena R. , Dokuparthi Praveen , Gottam Hima B. , Botha Kiran K. , Parapati Divya R. , Vinod Thottumkara K. 
Published: April 2009

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.