bluuebunny/crossref_metadata_2025 huggingface dataset:
Co‐current stratified laminar flow of two immiscible liquids in a rectangular conduit
Authors: Charles M. E. , Lilleleht L. U.
Published: June 2009

Theoretical expressions have been derived for velocity distribution and volumetric flow rates for the co‐current laminar stratified flow of two immiscible liquids in rectangular conduits. Results are presented in terms of the relative depth of the more viscous phase and the pressure gradient reduction factor for a wide range of viscosity and aspect ratios.

Theoretical results are reasonably well verified by experimental data at viscosity and aspect ratios of 5.326 and 7.95:1 respectively. The results suggest that a Lockhart‐Martinelli type correlation should be valid at high viscosity ratios and at low input volume fractions of the more viscous phase.
A versatile radiation source for studying gamma‐initiated reactions
Authors: Hodgins J. W. , Werezak G. N. , Ross S. L.
Published: June 2009

For the investigation of chemical reactions initiated by ionizing radiation, a gamma source has been constructed employing Cobalt‐60 as the emitter. This source is used in a radiation laboratory equipped with manipulators and therefore, has a wide range of applicability. Dose rate, total dosage, and radiation environment can be varied for either batch or flow type experiments. The design and flux characteristics of this source are described.
The role of fluids in comminution
Authors: Kapur P. C. , Mular A. L. , Fuerstenau D. W.
Published: June 2009

A relation is presented that describes the comminution of a solid in a ball mill, either alone or as a mixture component; and the effect of suspending fluids on the parameters of this relation is presented. The size distributions of products obtained from grinding in water, air, and tetrabromoethane are interpreted in terms of the effect of fluids on the relative proportions of abrasion, chipping, and impact events occurring in the mill. In the ball milling of mixtures, components have been shown to grind without significant interaction. Special effects that result when a material is lighter than the suspending fluid are discussed.
Axial mixing of liquid in gas‐liquid flow through packed beds
Authors: Hoogendoorn C. J. , Lips J.
Published: June 2009

The axial mixing in the liquid phase of a gas‐liquid flow through a packed column was studied with air and water flowing counter‐currently in a 1.33 ft. diameter column with 1/2‐in. Raschig rings.

The results for bubble flow (liquid continuous) indicate that liquid staging corresponds to about one ideal mixing stage per foot in the range of flow rates investigated. An approximate correlation for the axial diffusion coefficient has been established.

In trickle operation strong tailing was found. This could be explained from exchange between the main stream and a static liquid hold‐up.
Production of potassium sulphate from a mixture of sodium and magnesium sulphatesn and potassium chloride
Authors: Gunn Brad
Published: June 2009

Potassium sulphate has been produced by a batch process from a mixture of sodium and magnesium sulphates, and potassium chloride. The process is made attractive by the production of additional products — magnesium chloride and sodium sulphate —, by the recirculation of brines and by the recovery of potassium chloride from the brine circuit. Purities of products throughout can be controlled by slight circuit adjustments and/or by additional water washes. Flow sheets have been prepared and several cycles of operation have proven that the process is reliable.
The pipeline flow of capsules: Part 8: An experimental investigation of the transport in oil of single, denser‐than‐oil, spherical and cylindrical capsules
Authors: Round G. F. , Bolt L. H.
Published: June 2009

In the present paper, the flow behavior of single capsules of regular shape transported by two mineral oils of kinematic viscosities 45 and 7 centistokes respectively, in a 1 1/4‐inch diameter pipeline, are reported. In terms of pipe Reynolds number this means that the data for the more viscous oil were obtained for the laminar flow regime and the data for the less viscous oil were obtained, for the most part, for turbulent flow. A specific gravity range of 1.19‐7.86, a capsule diameter/pipe diameter ratio range of 0.39 (0.40)‐0.89 (0.90) and in the case of cylinders, lengths of 2‐in., 4‐in., and 7‐in. were investigated.
The mechanics of large gas bubbles in tubes: I. Bubble velocities in stagnant liquids
Authors: Brown R. A. S.
Published: June 2009

The effect of liquid viscosity on the rate of rise of a large gas bubble through stagnant liquid in a tube is shown to be limited to that on the film flow past the bubble on the wall of the tube. A criterion of similarity between the shapes of bubbles in different liquids is obtained experimentally which enables development of a correlation for the velocities of rise. This correlation is shown to be in good agreement with experimental results for systems in which the effects of surface tension and liquid viscosity on the frontal flow are negligible.
The mechanics of large gas bubbles in tubes: II. The prediction of voidage in vertical gas‐liquid flow
Authors: Brown R. A. S. , Govier G. W.
Published: June 2009

Material balance considerations define a relation between the voidage in gas‐liquid slug flow and the linear velocity of the gas bubbles for flow in a vertical tube. To utilize this relation for the correlation of gas content or voidage, a model is proposed for the liquid flow around an individual gas bubble taking into account the effect of liquid viscosity. While the model is not solvable analytically, a form for the correlation of bubble velocities in moving streams of liquid is developed from the material balance on the liquid. This correlation is found to describe experimental results from all flow patterns.
The mechanism of wall to fluid heat transfer in particulately fluidized beds
Authors: Wasmund B. , Smith J. W.
Published: June 2009

A proposed model for predicting heat transfer from a wall to a fluidized bed by particle convection has been based on particle velocities and radial temperature profiles. Solutions for two cases have been obtained:

Case I: The thermal resistance in the particles is small relative to that of the film surrounding them.

Case II: The resistance to heat transfer in the particle is of the same order as that in the surrounding film.

These solutions have been used to calculate particle convective heat transfer coefficients for water‐fluidized beds of 1.1 mm. and 1.53 mm. diameter glass spheres. The results are compared with reported experimental data, and indicate that particle convective transfer is 50 to 60% of the total heat transfer for Case II, and 30 to 40% for Case I.

In some liquid‐fluidizing systems, the thermal conductivity of the particles should have an effect, and the reason this has not been found experimentally is suggested.
Estimation of k‐constants for binary aliphatic hydrocarbon mixtures: Application to methane‐free systems
Authors: Ekiner Okan , Thodos George
Published: June 2009

Correlations have been developed for the prediction of vapor‐liquid equilibrium constants of methane‐free binary hydrocarbon mixtures. Each of these correlations has been associated with the parameter t, and presents relationships between the normalized reduced state variables, β/β0 and PR/PRS, for constant reduced temperatures. K values have been calculated and were compared with experimental values for the three binary systems, n‐butane—n‐heptane (τ = 1.36), ethane—n‐butane (τ = 1.48), and ethane—n‐heptane (τ = 2.02) used to develop the correlations of this study. These comparisons produced an average deviation of 5.03% for 80 points. Checks have been carried out on five other systems of a different nature to produce an average deviation of 6.65% for 29 additional points.
The use of mixtures of methyl ethyl ketone and methyl isobutyl ketone as dewaxing solvent and the dehydration of such mixtures by distillation
Authors: Butler R. M. , Macleod D. M.
Published: June 2009

It has been found that anhydrous mixtures of methyl ethyl ketone with methyl isobutyl ketone can be used as very effective dewaxing solvents. Such a mixture containing 70% methyl isobutyl ketone gives a performance essentially equivalent to that obtained with the much more expensive, yet, up until now, technically preferred methyl n‐propyl ketone.

For the same dewaxed oil pour point, dry mixtures of methyl ethyl ketone and methyl isobutyl ketone (and also as described previously methyl n‐propyl ketone) do not require as low filtering temperatures yet give higher filter rates than the widely employed mixtures of methyl ethyl ketone and aromatics. The continuous dehydration of mixtures of methyl ethyl ketone and methyl isobutyl ketone by distillation is also described. This operation is complicated by the fact that methyl ethyl ketone forms a binary, homogeneous azeotrope with water. The process which is described is rather unusual in that it combines some of the features of extractive distillation and also some of those of azeotropic distillation.
A catalyst mounting technique for close temperature control
Authors: Alexander W. A. , Tollefson E. L.
Published: June 2009

A novel technique for mounting the Cambron‐McKim silver catalyst has been developed which provides a highly conducting metal path between the catalyst and the temperature control medium. Its effectiveness as a means of maintaining control over a highly exothermic reaction has been demonstrated in a small pilot plant for the oxidation of ethylene to ethylene oxide.
On reactor design for complex systems of first‐order chemical reactions
Authors: Wei James
Published: June 2009

The mathematical problems of reactor design and performance depend primarily on the solution of a set of partial differential or difference equations. These equations are linear if the reactions are first‐order, if temperature variations are not significant, and if mass transfer by diffusion obeys Fick's law. When a reactor problem can be solved for a single irreversible first‐order reaction, it can also be solved for a system of coupled first‐order reactions of any number of chemical species and of arbitrary complexity.
Liquid‐liquid extraction with association effects
Authors: Johnson A. I. , Raal J. D.
Published: June 2009

Acetic and propionic acids were transferred from aqueous solutions into n‐heptyl alcohol, diisobutyl ketone, diisopropyl ether, and n‐heptane in an extraction cell of the Lewis type. The experiments were conducted over wide ranges of concentration to study the concentration dependence of the mass transfer coefficient.

In the extraction experiments with isopropyl ether and diisobutyl ketone as solvents, the overall mass transfer coefficients were found to vary markedly with concentration in contrast to the results with n‐pentane as solvent. These results could not be predicted by conventional mass transfer theory, but were in broad qualitative agreement with the predictions of a diffusion reaction model. An empirical “association factor” was proposed.

Diffusion experiments were carried out in diaphragm diffusion cells to test the predicted concentration dependence of the diffusion coefficient.
Design equations for multicomponent gas absorption
Authors: Cullwan Harry T.
Published: June 2009

The recently developed linearized theory of multicomponent mass transfer(1, 2, 3, 4) is applied to the case of gas absorption in a plate column. Matrix generalizations of the well‐known binary design equations are obtained using the diagonalizing procedure of Toor(1). The results demonstrate that the theory provides a general framework for the direct incorporation of diffusional and thermodynamic interaction effects into design procedures for multicomponent systems.
Heat transfer in the melting of solids to non‐newtonian liquids
Authors: Skelland A. H. P.
Published: June 2009

Relationships relevant to the design of industrial melters are developed for the case in which the molten material is a time‐independent non‐Newtonian fluid of the Power Law type. Expressions are derived for the local and mean values of the heat transfer coefficient in the melting of a solid slab on a hot, inclined, plane surface at constant temperature. The equations developed are restricted to laminar flow of the melt, and a criterion is therefore presented for checking that the molten film between the hot surface and the slab is actually in laminar flow throughout its entire length.
Dissociation and heat transfer in laminar flow
Authors: Rothenberg R. I. , Smith J. M.
Published: June 2009

An analytic study of heat transfer and temperature and composition distribution was conducted for a reacting fluid in laminar flow in a tubular reactor. The reaction chosen was reversible and homogeneous of the form A ⇆ 2U.

Numerical solutions were obtained by machine computation for conditions of chemical equilibrium and of finite kinetics. For endothermic, dissociative reactions the radial energy transfer due to diffusion adds to the contribution due to a temporary difference. Nusselt numbers up to 10 fold greater than those for the corresponding inert system are obtained. The diffusion contribution is a maximum when the radial mass transfer is not subject to a reaction resistance; i.e. at equilibrium.
Heat transfer studies in a climbing film evaporator: Part I. Heat transfer from condensing steam to boiling water
Authors: Gupta A. S. , Holland F. A.
Published: June 2009

Hard water was concentrated using steam heating in a single tube climbing film evaporator, of length 9 ft. and external diameter 1 inch.

The heat flux Q/A in BTU/hr. sq. ft. was found to be related to the feed rate of the water M lb./hr. and its temperature Ti °F by the equation

Q/A = ψ M0.6 + 90.3 (Tb – Ti) Cp

where ψ is a graphically read function of the temperature difference driving force between the condensing steam and the boiling water. The data fit the above equation with a standard deviation of 2.6%.

The empirically derived equation for heat flux was also found to represent the data for other aqueous solutions with reasonable accuracy.
Silica and alumina powders: Part II. Coherence and strength of compacts
Authors: Griffith Richard M.
Published: June 2009

The mechanical strength of compacted silica and alumina powders was studied to gather information about agglomeration in general and the preparation of catalyst supports in particular. Substantial strength developed only if the conditions of preparation favored formation of oxygen crosslinks between adjacent particles through reaction between hydroxyl groups on adjacent surface. Strength rose sharply with solids fraction once a minimum value of about 0.2 was achieved and, in general, behaved as predicted from brittle fracture theory.
Mass transfer in a turbulent radial wall jet
Authors: Dawson D. A. , Trass O.
Published: June 2009

Experimental and theoretical coefficients are reported for mass transfer in a turbulent radial wall jet initiated by an impinging free jet. The hydrodynamic solution was obtained by the momentum integral technique, and mass transfer was predicted by analogy.

Point mass transfer data were obtained for air‐naphthalene and cinnamic acid‐water systems. At low Schmidt numbers, experimental coefficients were slightly above the theoretical prediction, and followed the theoretical trend with radial distance and nozzle Reynolds number from 10,000 to 60,000. Coefficients at high Schmidt numbers showed large positive deviations from theory, which decreased with radial distance and increased with Schmidt number. These discrepancies were attributed to surface roughness effects.
Impact tube measurement of flow patterns, velocity profiles and pumping capacities in mixing vessels
Authors: Wolf D. , Manning F. S.
Published: June 2009

Impact‐static‐shielded tubes were found to be suitable for measuring time‐average velocities in the jet stream flow generated by the marine propeller. Pumping capacities and entrainment flow were then calculated from these velocity profiles. Pumping capacities were correlated by: Q = KpND3.

When the tank contained water: Kp = 0.54. The same probe was found to be useful in evaluating qualitatively the flow patterns from turbine and paddle type impellers. The effect of several parameters on the flow patterns are reported.
Dynamic optimisation: An extension of the direct method of lyapunov
Authors: Stevens William F. , Wanninger L. A.
Published: June 2009

This paper presents a method for the dynamic optimization of a chemical process, applicable whether or not the uncontrolled system is stable at the desired operating conditions. The system has several advantages over other methods of dynamic optimization: (1) Dimensionality is not a limitation; (2) Inequality constraints are handled directly; (3) A two‐point boundary value problem is not encountered; and (4) Control is designed around a stability criterion. Numerical results on a second order stirred‐tank reactor system are presented in order to verily the practicality of the proposed method.
Solution of problems involving systems of distillation columns
Authors: Nartker T. A. , Skrygley J. M. , Holland C. D.
Published: June 2009

A convergence method (called the Θ‐method) and calculational procedure have been developed which may be applied to any system of distillation units. The procedure makes use of the programs of the individual units without modification. This amounts to the use of the programs of the individual units as building blocks for the construction of the model for the system. Any number of independent feeds to any one of the distillation units may be specified, and any number of sidestreams may be either withdrawn from the system or fed to any other unit of the system.
New optimization method is highly suitable for chemical engineering applications
Authors: Methot J. C. , Cloutier Leonce , Cholette A.
Published: June 2009

A new optimization method involving only elementary calculus represents a significant simplification over existing methods. It makes for the easy and rapid solution of many complex problems in chemical engineering.

In addition to making use of the first derivative, as in most other methods, the new method also calls for the second derivative of the function to be optimized. When going from one point to another, the method consists essentially in adding simultaneously to each independent variable an increment which, for a given variable, is equal to the negative ratio of the first partial derivative to the second partial derivative, and so on until optimum conditions are reached.

A few mathematical examples illustrate the speed of the new method and permit comparisons with other well known methods. Numerical applications pertaining to chemical engineering are also presented.
Isotropic turbulent mixing with boundary sources
Authors: Rosensweig R. E.
Published: June 2009

A type of turbulent mixing, ubiquitous in occurrence as a limiting case, is defined and given analytical treatment. By combining the Kolmogoroff and Corrsin concepts of inertial subrange with consistent application of the divergence theorem of Gauss, predictions are made for statistical turbulence and mixing parameters in uniformly mixed regions into which fluid streams are introduced of arbitrary number, concentration and speed.
Vapor‐liquid equilibrium data for system: Ethanol‐water saturated with potassium acetate
Authors: Meranda D. , Furter W. F.
Published: June 2009

Isobaric vapor‐liquid equilibrium data at atmospheric pressure are reported for the system ethanol‐water saturated with potassium acetate. Solubility data for potassium acetate in boiling solutions of aqueous ethanol, as a function of ethanol concentration, are also reported. Potassium acetate, a salt highly soluble in aqueous solution, was observed to exert a very large effect on relative volatility.
The horizontal stacked disk still: A high speed, high efficiency, laboratory distillation apparatus
Authors: Butler R. M. , Pasternak I. S.
Published: June 2009

A novel type of high efficiency, high speed, laboratory still has been developed for obtaining distillation curves on small (5 ml) samples of high boiling (300°F+) materials. The apparatus is simple consisting essentially of a hollow, baffled, horizontal metal bar heated at one end by means of an electrical cartridge heater. In operation, the feed sample is placed in one end of the still, the heater and a vacuum pump turned on, and distillation fractions collected at the other end. Conventional distillation curves are obtained directly.
Computational methods in process optimization: I. Recycle plant with bounded controls
Authors: Paynter J. D. , Bankoff S. G.
Published: June 2009

Computational methods for optimal cooling jacket design on a tubular reactor with recycle of unconverted reactant were studied. A successful procedure employed a gradient technique for control‐vector iteration, followed by a two‐dimensional search to locate the optimal switching points. On the other hand, boundary condition iteration was notably unsuccessful for this “bang‐bang” control problem.
Solubility parameters of hydrocarbons
Authors: Bradford Michael L. , Thodos George
Published: June 2009

Information available in the literature on vapor pressures, saturated vapor and liquid densities, and critical constants, for different hydrocarbons, has permitted the calculation of δ, the solubility parameter advanced by Hildebrand, at temperatures up to and including the critical point. For these hydrocarbons, the residual quantity, δ‐δc was found to depend on 1‐TR according to the relationship,

where k appears to be a constant within different classes of hydrocarbons. Values of δ calculated with this equation were compared with the corresponding values used to develop it, and produced an average deviation of 0.85% for 153 values considered which represented 17 hydrocarbons.
Silicon Analogues of the RXR‐Selective Retinoid Agonist SR11237 (BMS649): Chemistry and Biology
Authors: Lippert W. Peter , Burschka Christian , Götz Kathrin , Kaupp Martin , Ivanova Diana , Gaudon Claudine , Sato Yoshiteru , Antony Pierre , Rochel Natacha , Moras Dino , Gronemeyer Hinrich , Tacke Reinhold
Published: June 2009

C/Si switch: Twofold sila‐substitution (C/Si exchange) in the RXR‐selective retinoids 4 a (SR11237) and 5 a leads to 4 b (disila‐SR11237) and 5 b, respectively. Chemistry and biology of the C/Si pairs are reported.

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SR11237 (BMS649, 4 a) is a pan‐RXR‐selective retinoid agonist. Its silicon analogue, disila‐SR11237 (4 b; twofold C/Si exchange), was prepared in a multistep synthesis by starting from 1,2‐bis(ethynyldimethylsilyl)ethane. In addition, the related C/Si analogues 5 a and 5 b, with an indane (disila‐indane) instead of a tetraline (disila‐tetraline) skeleton, were synthesized. The C/Si pairs 4 a/4 b and 5 a/5 b were studied for their interaction with retinoid receptors and were demonstrated to be highly potent RXR‐selective (“rexinoid”) agonists. Interestingly, twofold C/Si exchange in the indane moiety of 5 a resulted in a 10‐fold increase in biological activity of the corresponding silicon‐containing rexinoid 5 b, possibly resulting from an increased receptor affinity or a divergent allosteric effect on co‐regulator‐binding surfaces. The crystal structures of the ternary complexes formed by 5 a and 5 b, respectively, with the ligand‐binding domain of hRXRα and a peptide of the co‐activator TIF2/GRIP1 revealed additional interactions of the disila analogue 5 b with the H7 and H11 residues, supporting the first option of increased binding affinity. This is the first demonstration of an increase in binding affinity of a ligand to a nuclear receptor by C/Si replacement, thereby adding this C/Si switch strategy to the repertoire of nuclear receptor ligand design.
Eigenvalues of the adjacency and Laplacian matrices for modified regular structural models
Authors: Kaveh A. , Rahami H.
Published: June 2009

The graph model of many space structures and finite element models can be formed using graph products. These structures are known asregularstructures. Methods for calculating the eigenvalues of the matrices corresponding to these models are already investigated. In practice for some structural models the addition of some nodes and members to the graph product is required. When such a node and the incident members are added to a regular model, it becomes amodified regularstructure. In this paper the eigenproblem of the matrices corresponding to these models is studied. The necessary formulations are derived and examples are presented to illustrate the practical value of the presented approach. Copyright © 2009 John Wiley & Sons, Ltd.
Circulating insulin antibodies: influence of continuous subcutaneous or intraperitoneal insulin infusion, and impact on glucose control
Authors: Radermecker R. P. , Renard E. , Scheen A. J.
Published: June 2009

The purification of animal insulin preparations and the use of human recombinant insulin have markedly reduced the incidence, but not completely suppressed, the development of anti‐insulin antibodies (IAs). Advances in technologies concerning the mode of delivery of insulin, i.e. continuous subcutaneous insulin infusion (CSII), continuous peritoneal insulin infusion (CPII) and more recently inhaled insulin administration, appear to significantly increase circulating levels of immunoglobulin G (IgG) anti‐IAs in diabetic patients. However, the increase is usually moderate and mostly transient as compared to previous observations with poorly purified animal insulin preparations. The clinical impact of these circulating anti‐IAs remains unclear. Nevertheless, several studies have suggested that antibodies could retard insulin action, leading to a worsening of postprandial hyperglycaemia and/or serve as a carrier, thus leading to unexpected hypoglycaemia. CPII may be associated with more marked and sustained increase in IAs levels, possibly related to the use of an unstable insulin and the formation of immunogenic aggregates of insulin. The possible clinical consequences of these high levels of IAs remain to be evaluated because a low‐glucose morning syndrome or severe insulin resistance with ketone bodies production have been reported in some cases. In conclusion, even if CSII and CPII may promote the development of circulating IAs, this increase does not lead to immunological insulin resistance, compared to that previously described with animal non‐purified insulin preparations, and seems to have only marginal influence on blood glucose control or complications in most diabetic patients. Copyright © 2009 John Wiley & Sons, Ltd.
Oral glucose tolerance test in Italian overweight/obese children and adolescents results in a very high prevalence of impaired fasting glycaemia, but not of diabetes
Authors: Cambuli Valentina M. , Incani Michela , Pilia Sabrina , Congiu Tiziana , Cavallo M. Gisella , Cossu Efisio , Sentinelli Federica , Mariotti Stefano , Loche Sandro , Baroni Marco G.
Published: June 2009

Background

Very few studies on glucose abnormalities in European overweight/obese children and adolescents are available, and scientific evidence on the value of standard oral glucose tolerance test (OGTT) in childhood is lacking. We therefore aimed to establish prevalence and features of impaired fasting glucose (IFG), impaired glucose tolerance (IGT) and type 2 diabetes (T2D) in a large cohort of Italian overweight/obese children and adolescents and to assess the validity of standard OGTT in the paediatric population.

Methods

This is a 1‐year observational study conducted on 736 (535 overweight/obese and 201 normal weight) consecutive paediatric patients attending the outpatient clinic of Paediatric Endocrine Unit. Clinical and biochemical parameters were collected for all participants. All overweight/obese subjects underwent OGTT.

Results

We observed a high prevalence of IFG (7.66%), more than twice that observed in other European children, but a low prevalence of IGT (3.18%) and T2D (0.18%). IFG was useless to predict IGT, having very low predictive value (7.3%) and sensitivity (17.6%). Compared to normal weight children, overweight/obese subjects showed significant differences in most metabolic and clinical parameters. In the overweight/obese group, having hyperglycaemia was associated to significantly higher blood pressure, homeostasis model assessment for insulin resistance, insulin and triglycerides.

Conclusions

In our children, the prevalence of IFG is higher than that reported in other European cohorts, whereas T2D is rare. IFG appears not useful to detect IGT in childhood. Paediatric diagnostic cut‐points, glucose load and timing of sampling need to be further validated to define glucose abnormalities in obese children that, compared with normal weight subjects, already are characterised by a different metabolic phenotype. Copyright © 2009 John Wiley & Sons, Ltd.
High‐Density Magnetite Nanoparticles Located in Carbon Hollow Microspheres with Good Dispersibility and Durability: Their One‐Pot Preparation and Magnetic Properties
Authors: Zheng Rongbo , Meng Xianwei , Tang Fangqiong
Published: June 2009

We report, for the first time, a one‐step, rapid, template‐free and continuous strategy for synthesising high‐density magnetite (Fe3O4) nanoparticles located in carbon hollow microspheres (MCHMs) in which Fe3O4 nanoparticles (8–20 nm) are randomly dispersed in the shells of carbon hollow microspheres. The synthesis is achieved through ultrasonic spray pyrolysis of aqueous solutions containing ferrous chloride and citric acid. Interestingly, it was found that there are some pores (2–6 nm) in the carbon shell. Magnetic hysteresis loop measurements show that the saturation magnetisation of MCHMs is as high as 48.2 emu g−1 which probably makes them more pliable to manipulation by the external magnetic field. Most importantly, because of the presence of carbon on their surfaces, MCHMs not only exhibit good resistance to acid but can also be easily dispersed in both polar and nonpolar solvents. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Retraction: Detailed Mössbauer Characterization of Fe2+Fur, the Active Form of the Ferric Uptake Regulation Protein from E. coli and Density Functional Calculations on Some Related Models
Authors: Horner Olivier , Oddou Jean‐Louis , Jeandey Claudine , Michaud‐Soret Isabelle , Mouesca Jean‐Marie
Published: June 2009

The Fe2+ center of iron‐substituted ferric uptake regulation protein (Fur) has been fully characterized by applied‐field Mössbauer spectroscopy, and two structural models for this center in Fur from E. coli (EC‐Fe2+Fur) have been developed by combining the crystallographic data available for Fur from Pseudomonas aeruginosa (PA‐Fur) in complex with Zn2+ and the EXAFS data for a PA‐Fur sample dialyzed against a Fe2+ solution or EC‐Fur in complex with Fe2+. The Mössbauer (isomer shift excluded) and spin‐Hamiltonian parameters have been estimated by density functional calculations for these models and compared to the experimental data. The geometry and the environment of the iron‐binding center in EC‐Fur and PA‐Fur are found to be similar, and the comparison of the observed and calculated quadrupole splitting values indicates that the model with a (3O,2N,1O) coordination (ΔEQ > 0) is a better representation of the environment around the iron center in EC‐Fe2+Fur.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

The article “Detailed Mössbauer Characterization of Fe2+Fur, the Active Form of the Ferric Uptake Regulation Protein from E. coli and Density Functional Calculations on Some Related Models” by Olivier Horner, Jean‐Louis Oddou, Claudine Jeandey, Isabelle Michaud‐Soret, Jean‐Marie Mouesca, published online on June 3, 2009 in Wiley Interscience (www.interscience.wiley.com, 10.1002/ejic.200900091) and in print (Eur. J. Inorg. Chem. 2009, 2959–2966), has been retracted (October 6, 2009) by the journal editor‐in‐chief, Dr Karen Hindson, and Wiley‐VCH, in accordance with the “EUCheMS Ethical Guidelines for Publication in Journals and Reviews” adhered to by the journal (EUCheMS Ethical Guidelines for Publication in Journals and Reviews, 2006, http://www.euchems.org/Publications/index.asp), due to lack of agreement among the authors regarding its publication.
Exceptional Coordination Mode of Unsaturated PNP Ligands (Me3Si)2C=PN(R)PPh2 with Palladium and Platinum Dichlorides: Insertion of Phosphaalkene Phosphorus Atoms into Metal–Chlorine Bonds
Authors: Lungu Daniela , Daniliuc Constantin , Jones Peter G. , Nyulászi László , Benkõ Zoltán , Bartsch Rainer , du Mont Wolf‐W.
Published: June 2009

Unique molecular bis‐chelate complexes M[(Me3Si)2C=P(Cl)N(1‐Ada)PPh2]2 (1‐Ada = 1‐adamantyl; 3: M = Pt; 4: M = Pd) were isolated as crystalline solids from solutions that contain mixtures of products from reactions of the metal dichlorides with the P‐phosphanylaminophosphaalkene (Me3Si)2C=PN(1‐Ada)PPh2 (1). Attachment of chloride ions to PdII‐ and PtII‐coordinated 1 leads to the novel anionic (alkylidene)(chlorido)(phosphanylamino)phosphanido ligand [(Me3Si)2C=P(Cl)N(1‐Ada)PPh2]–, which contains a stereogenic phosphorus atom. With PdCl2(COD), only the centrosymmetric (R,S) isomer 4a was isolated, whereas three of the four possible isomeric platinum complexes Pt[(Me3Si)2C=P(Cl)N(1‐Ada)PPh2]2 (3a–3c) were investigated crystallographically. DFT calculations on model compounds indicate that the enhanced electrophilicity of the chelating phosphaalkene ligand 1 leads to chlorine migration from the metals to the phosphaalkene phosphorus atom.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
New Aryloxy and Benzyloxy Derivatives of Titanium as Catalysts for Bulk Ring‐Opening Polymerization of ϵ‐Caprolactone and δ‐Valerolactone
Authors: Gowda Ravikumar R. , Chakraborty Debashis , Ramkumar Venkatachalam
Published: June 2009

A variety of aryloxy compounds and benzyloxy derivatives of TiIV were synthesized from Ti(iPrO)4 using the alcoholysis route. These compounds were characterized using various analytical methods and single‐crystal X‐ray diffraction. Multinuclear NMR studies prove high degree of fluxional behavior of these compounds in solution. They adopt a dimeric structure in the solid state as seen from X‐ray diffraction studies on a few of them. These compounds are powerful catalysts for the ring‐opening polymerization of ϵ‐caprolactone (CL) and δ‐valerolactone (VL) resulting in high polymers with good number average molecular weights (Mn). Significant control can be achieved by performing such polymerizations in the presence of benzyl alcohol (BnOH). This is reflected by higher Mn and much narrower molecular weight distributions (MWDs) of the resulting polymers. Kinetic studies reveal that the rates of such polymerizations are much higher in the presence of BnOH. 1H NMR and MALDI‐TOF studies of low molecular weight oligomers suggest that these polymerizations proceed by the activated monomer mechanism in the presence of BnOH. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Controlling the Helicity of Hydroxyquinoline Metal Complexes Based on a Macrocyclic Peptide Scaffold
Authors: Ziegler Eva , Haberhauer Gebhard
Published: June 2009

A straightforward synthesis of a C3‐symmetric imidazole‐containing macrocyclic peptide with three hydroxyquinoline side arms is presented. Complex formation with various metal ions (Al3+, Ga3+, Fe3+, La3+ and Y3+) was investigated by spectrophotometric methods. CD spectroscopy revealed a highly diastereoselective binding of these ions at room temperature. In the case of Al3+, Ga3+ and La3+ complexes, Job plot analyses gave evidence of pure 1:1 stoichiometry. Ab initio calculations for the Al3+ and Ga3+ complexes showed that the Λ isomers are considerably stabilized relative to the Δ isomers. Furthermore, the calculated CD spectra for the Al3+ complexes confirm the formation of the Λ isomers in solution. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
The impact of magnitude of harm and perceived difficulty of making reparations on group‐based guilt and reparation towards victims of historical harm
Authors: Berndsen Mariëtte , McGarty Craig
Published: June 2009

The present research investigates how reading stories about past mistreatment of children who had been in institutional care affects support for reparations, perceived difficulty of reparations and group‐based guilt were investigated in two experiments. In Study 1 we showed that, when the stories increased in perceived harm, so did the perceived difficulty of making reparations whereas group‐based guilt decreased. Furthermore, both perceived difficulty of making reparations and group‐based guilt predicted support for reparation. It was suggested that these findings were due to a natural confound between the severity of harm and the difficulty of reparations. Study 2 included a direct manipulation of perceived difficulty that was intended to weaken or strengthen the ability to make reparations. This study demonstrated stronger group‐based guilt when reparations were potentially possible and not when they are impossible. Moreover, support for reparations varied as a function of perceived difficulty of reparations and group‐based guilt mediated that relationship. The research has two key implications. First, advocates of reparations as a mechanism for reconciliation and community healing need to consider the degree to which reparations are perceived to be possible and consider ways of addressing those perceptions. Second, the research provides an experimental demonstration to the power of stories about experience to bolster support for social change. Copyright © 2009 John Wiley & Sons, Ltd.
We are still better than them: A longitudinal field study of ingroup favouritism during a merger
Authors: Gleibs Ilka H. , Noack Peter , Mummendey Amelie
Published: June 2009

The authors examine the impact of predictors for ingroup favouritism and a positive attitude towards a university merger by conducting a longitudinal field study investigating students' perceptions of a merger. Thus, the focus of this paper lies on the developmental and dynamic aspect of social identity processes and the test of directional hypotheses in an applied setting. Based on a cross‐lagged regression approach, it was shown that pre‐merger identification increased favouritism, but favouritism also increased pre‐merger identification. Moreover, ingroup favouritism was uni‐directionally related to a negative attitude towards the merger. Contact with the merger partner revealed lagged effects on ingroup favouritism. These results confirm that issues of identity change and compatibility are crucial aspects in understanding merger adjustment and support. Copyright © 2009 John Wiley & Sons, Ltd.
Free convection of a dusty‐gas flow along a semi‐infinite vertical cylinder
Authors: Palani G. , Kim Kwang‐Yong
Published: June 2009

An analysis is performed to study the free convection of a dusty‐gas flow along a semi‐infinite isothermal vertical cylinder. The governing equations of the flow problem are transformed into non‐dimensional form and the resulting nonlinear, coupled parabolic partial differential equations have been solved numerically using an implicit finite difference scheme of Crank–Nicholson type. The flow variables such as gas–velocity, dust‐particle velocity and temperature, shearing stress and heat transfer coefficients are calculated numerically for various parameters occurring in the problem. It is observed that due to the presence of dust particles, the gas velocity is found to decrease. Copyright © 2009 John Wiley & Sons, Ltd.
Bayesian mixture modeling of gene‐environment and gene‐gene interactions
Authors: Wakefield Jon , De Vocht, Frank , Hung Rayjean J.
Published: June 2009

With the advent of rapid and relatively cheap genotyping technologies there is now the opportunity to attempt to identify gene‐environment and gene‐gene interactions when the number of genes and environmental factors is potentially large. Unfortunately the dimensionality of the parameter space leads to a computational explosion in the number of possible interactions that may be investigated. The full model that includes all interactions and main effects can be unstable, with wide confidence intervals arising from the large number of estimated parameters. We describe a hierarchical mixture model that allows all interactions to be investigated simultaneously, but assumes the effects come from a mixture prior with two components, one that reflects small null effects and the second for epidemiologically significant effects. Effects from the former are effectively set to zero, hence increasing the power for the detection of real signals. The prior framework is very flexible, which allows substantive information to be incorporated into the analysis. We illustrate the methods first using simulation, and then on data from a case‐control study of lung cancer in Central and Eastern Europe. Genet. Epidemiol. 34:16–25, 2010. © 2009 Wiley‐Liss, Inc.
Prostate cancer segregation analyses using 4390 families from UK and Australian population‐based studies
Authors: MacInnis Robert J. , Antoniou Antonis C. , Eeles Rosalind A. , Severi Gianluca , Guy Michelle , McGuffog Lesley , Hall Amanda L. , O'Brien Lynne T. , Wilkinson Rosemary A. , Dearnaley David P. , Ardern‐Jones Audrey T. , Horwich Alan , Khoo Vincent S. , Parker Christopher C. , Huddart Robert A. , McCredie Margaret R. , Smith Charmaine , Southey Melissa C. , Staples Margaret P. , English Dallas R. , Hopper John L. , Giles Graham G. , Easton Douglas F.
Published: June 2009

Familial aggregation of prostate cancer is likely to be due to multiple susceptibility loci, perhaps acting in conjunction with shared lifestyle risk factors. Models that assume a single mode of inheritance may be unrealistic. We analyzed genetic models of susceptibility to prostate cancer using segregation analysis of occurrence in families ascertained through population‐based series totaling 4390 incident cases. We investigated major gene models (dominant, recessive, general, X‐linked), polygenic models, and mixed models of susceptibility using the pedigree analysis software MENDEL. The hypergeometric model was used to approximate polygenic inheritance. The best‐fitting model for the familial aggregation of prostate cancer was the mixed recessive model. The frequency of the susceptibility allele in the population was estimated to be 0.15 (95% confidence interval (CI) 0.11–0.20), with a relative risk for homozygote carriers of 94 (95% CI 46–192), and a polygenic standard deviation of 2.01 (95% CI 1.72–2.34). These analyses suggest that one or more genes having a strong recessively inherited effect on risk, as well as a number of genes with variants having small multiplicative effects on risk, may account for the genetic susceptibility to prostate cancer. The recessive component would predict the observed higher familial risk for siblings of cases than for fathers, but this could also be due to other factors such as shared lifestyle by siblings, targeted screening effects, and/or non‐additive effects of one or more genes. Genet. Epidemiol. 34:42–50, 2010. © 2009 Wiley‐Liss, Inc.
Phosphorylation of derivatives of β‐dialkyaminocrotonitriles with phosphorus(III) halides
Authors: Kostyuk Aleksandr N. , Svyaschenko Yurii V. , Barnych Bogdan B. , Sibgatulin Dmitriy A. , Rusanov Eduard B. , Volochnyuk Dmitriy M.
Published: June 2009

The reaction of β‐dialkylaminocrotontriles with phosphorus(III) halides has been investigated. The basicity of the dialkylamino group influences the phosphorylation markedly, with pyrrolidine being the amine of choice. It was found that a solvent and the ratio of triethylamine play a significant role in phosphorylation. Although chloro‐ and dichlorophosphine derivatives proved impossible to separate as individual compounds; their solutions can be successfully used for further transformations. © 2009 Wiley Periodicals, Inc. Heteroatom Chem 20:194–201, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20532
A novel and convenient method for synthesis of carbamoyl and thiocarbamoyl phosphonates
Authors: Kaboudin Babak , Zahedi Hazegh
Published: June 2009

A simple, efficient, and general method has been developed for the synthesis of carbamoyl and thiocarbamoyl phosphonic esters using CaCl2 as an efficient Lewis base catalyst. Carbamoyl and thiocarbamoyl phosphonic esters were obtained in good yield (37%–65%) and purity under mild conditions by the reaction of diethyl phosphite with isocyanates and isothiocyanates in the presence of CaCl2. This method is easy, rapid, and good‐yielding reaction for the synthesis of carbamoyl and thiocarbamoyl phosphonic esters. © 2009 Wiley Periodicals, Inc. Heteroatom Chem 20:250–253, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20538
Indium triflate‐catalyzed one‐pot synthesis of 14‐alkyl or aryl‐14H‐dibenzo[a, j]xanthenes in water
Authors: Urinda Sharmistha , Kundu Dhiman , Majee Adinath , Hajra Alakananda
Published: June 2009

A mild, efficient, and environment friendly method has been developed for the synthesis of 14‐alkyl or aryl‐14H‐dibenzo[a, j]xanthenes by condensation of 2‐naphthol and aldehydes in the presence of a catalytic amount of indium(III) triflate (2 mol%) in water at 100°C. Different types of aromatic and aliphatic aldehydes are used in the reaction, and in all cases the products synthesized in moderate to excellent yields. © 2009 Wiley Periodicals, Inc. Heteroatom Chem 20:232–234, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20539
Time‐varying yield curve dynamics and monetary policy
Authors: Mumtaz Haroon , Surico Paolo
Published: June 2009

Monetary policy, the yield curve and the private sector behaviour of the US economy are modelled as a time‐varying structural vector autoregression. The monetary policy shocks of the early 1980s explain a large portion of the persistence of inflation and the level of the term structure. Changes in inflation expectations implied by the yield curve account for the persistence of the federal funds rate. Failures of the expectations hypothesis are rare, and coincided with the credibility building of Paul Volcker's Fed tenure at the beginning of the 1980s and the sequence of consecutive policy rate cuts around the time of the early 1990s recession. Copyright © 2009 John Wiley & Sons, Ltd.
Biological and antibacterial properties of plasma sprayed wollastonite/silver coatings
Authors: Li Baoe , Liu Xuanyong , Cao Cong , Dong Yuqi , Ding Chuanxian
Published: June 2009

In this work, plasma sprayed wollastonite/silver coatings were prepared to obtain an implant material having excellent bioactivity, cytocompatibility as well as antibacterial property. The surface characteristics of wollastonite/silver coating were investigated by scanning electron microscopy, energy dispersive spectrometer, atomic absorbance spectroscope and x‐ray diffraction. The bioactivity was examined by simulated body fluid soaking test. The antibacterial activity against Escherichia coli was examined by bacterial counting method. And the cytocompatibility and in vitro osteotoxicity was evaluated by alamarBlue™ Assay using MG‐63 osteoblasts. The results showed that silver existed in the wollastonite coating homogeneously as silver oxide and metal silver, which ensured a sustained release of silver for 28 days in deionized water. The loaded silver showed strong inhibition against the growth of Escherichia coli, however exhibited no osteotoxicity. Although the wollastonite/silver coating can not induce apatite formation as quickly as the wollastonite coating did in simulated body fluid, it still exhibited good bioactivity. Therefore, the plasma sprayed wollastonite/silver coating is a promising implant material to be applied in surgery, reducing postoperative infections. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 2009