bluuebunny/crossref_metadata_2025_split huggingface dataset:
Theoretical study and rate constant calculation for reaction of CF3CH2OH with OH
Authors: Wang Ying , Liu Jing‐Yao , Li Ze‐Sheng , Wang Li , Sun Chia‐Chung 
Published: January 2007

AbstractThe reaction mechanism of CF3CH2OH with OH is investigated theoretically and the rate constants are calculated by direct dynamics method. The potential energy surface (PES) information, which is necessary for dynamics calculation, is obtained at the B3LYP/6‐311G (d, p) level. The single‐point energy calculations are performed at the MC‐QCISD level using the B3LYP geometries. Complexes, with the energies being less than corresponding reactants and products, are found at the entrance and exit channels for methylene‐H‐abstraction channel, while for the hydroxyl‐H‐abstraction channel only entrance complex is located. By means of isodesmic reactions, the enthalpies of the formation for the species CF3CH2OH, CF3CHOH, and CF3CH2O are estimated at the MC‐QCISD//B3LYP/6‐311G (d, p) level of theory. The rate constants for two kinds of H‐abstraction channels are evaluated by canonical variational transition state theory with the small‐curvature tunneling correction (CVT/SCT) over a wide range of temperature 200–2000 K. The calculated results are in good agreement with the experimental values in the temperature region 250–430 K. The present results indicate that the two channels are competitive. Below 289 K, hydroxyl‐H‐abstraction channel has more contribution to the total rate constants than methylene‐H‐abstraction channel, while above 289 K, methylene‐H‐abstraction channel becomes more important and then becomes the major reaction channel. © 2007 Wiley Periodicals, Inc. J Comput Chem 28: 802–810, 2007
Generation of basis sets with high degree of fulfillment of the Hellmann‐Feynman theorem
Authors: Rico J. Fernández , López R. , Ema I. , Ramírez G. 
Published: January 2007

AbstractA direct relationship is established between the degree of fulfillment of the Hellman‐Feynman (electrostatic) theorem, measured as the difference between energy derivatives and electrostatic forces, and the stability of the basis set, measured from the indices that characterize the distance of the space generated by the basis functions to the space of their derivatives with respect to the nuclear coordinates. On the basis of this relationship, a criterion for obtaining basis sets of moderate size with a high degree of fulfillment of the theorem is proposed. As an illustrative application, previously reported Slater basis sets are extended by using this criterion. The resulting augmented basis sets are tested on several molecules finding that the differences between energy gradient and electrostatic forces are reduced by at least one order of magnitude. © 2007 Wiley Periodicals, Inc. J Comput Chem 28: 748–758, 2007
The way of stabilizing non‐IPR fullerenes and structural elucidation of C54Cl8
Authors: Gao Xingfa , Zhao Yuliang 
Published: January 2007

AbstractRecently, a new non‐IPR chlorofullerene C54Cl8 was isolated experimentally (Science 2004, 304, 699). To explore the ways to stabilize non‐IPR fullerenes, the authors studied all of the possible isomers of C54 fullerene and some of the C54Cl8 isomers at PM3, B3LYP/3‐21G, and B3LYP/6‐31G* levels. Combined with analysis of pentagon distributions, bond resonance energies, and steric strains, C54:540 with the least number of 5/5 bonds was determined to be the thermodynamically best isomer for the C54Cl8. Based on C54:540, the most probable structure of the experimental C54Cl8 was elucidated. The results suggested one of the necessary conditions of stabilizing non‐IPR fullerenes: chemical derivatizations of either endohedral complexation or exohedral addition need to sufficiently stabilize all of the kinetically unstable 5/5 bonds of the cages. © 2007 Wiley Periodicals, Inc. J Comput Chem 28: 795–801, 2007
Myoclonus–dystonia syndrome with severe depression is caused by an exon‐skipping mutation in the ε‐sarcoglycan gene
Authors: Misbahuddin Anjum , Placzek Mark , Lennox Graham , Taanman Jan‐Willem , Warner Thomas T. 
Published: January 2007

AbstractWe describe two affected individuals in a family with myoclonus–dystonia syndrome complicated with severe depression. One individual committed suicide. Molecular genetic analysis revealed a heterozygous point mutation in the ε‐sarcoglycan gene, which we show leads to skipping of exon 5. This report suggests that the psychiatric spectrum of MDS includes more severe depression. © 2006 Movement Disorder Society
Fatal encephalitis in a patient with refractory celiac disease presenting with myorhythmia and carpal spasm
Authors: Dimberg Elliot L. , Crowe Sheila E. , Trugman Joel M. , Swerdlow Russell H. , Lopes M. Beatriz , Bourne T. David , Burns Ted M. 
Published: January 2007

AbstractWe report the case of a woman with refractory celiac disease who developed abnormal spontaneous movements of the extremities and face consistent with myorhythmia. Investigation led to a diagnosis of encephalitis, confirmed by postmortem examination. The movements were likely caused by nonparaneoplastic encephalitis associated with refractory celiac disease. Etiologic and diagnostic considerations and treatment options are discussed. © 2006 Movement Disorder Society
Diagnostic indicators of restless legs syndrome in primary care consultations: The DESYR study
Authors: Crochard Anne , El Hasnaoui Abdelkader , Pouchain Denis , Huas Dominique , Arnulf Isabelle , Krieger Jean , Lainey Eric , Le Jeunne Philippe , Leger Damien , Schuck Stéphane , Texier Nathalie , Tison François , Montplaisir Jacques 
Published: January 2007

AbstractThe objective of this study is to determine whether spontaneous complaints about sleep or the legs could be used as potential indicators of restless legs syndrome (RLS) in primary care. A total of 351 general practitioners participated in the study. In a first historical patient identification phase, all patients with spontaneous complaints of sleep or leg symptoms over the previous year were identified. A control group without such complaints was identified. In a second prospective data collection phase, those who consulted a participating physician were interviewed to assess consensus diagnostic criteria of RLS. Severity was assessed with the International Restless Legs Syndrome Study Group severity rating scale. Of 1,405,823 patients consulting during the historical phase, a leg complaint was reported in 61,685 and a sleep complaint in 40,568. A total of 1,432 consulted during the prospective phase. A diagnosis of RLS was assigned to 42.6% of patients with leg complaints, 35.5% of those with sleep complaints, 54.9% of those with both complaints, and 12.9% of those with no complaints. Median RLS severity scores were 18.8 to 20.4. A total of 63.7% of patients were prescribed a venotonic, 43.7% a hypnotic, and 41.5% an anxiolytic. Complaints of sleep or leg symptoms are frequently associated with a diagnosis of RLS, and their presence should alert the physician to the possibility of a differential diagnosis of RLS. © 2006 Movement Disorder Society
Augmentation of restless legs syndrome with long‐term tramadol treatment
Authors: Vetrugno Roberto , La Morgia Chiara , D'Angelo Roberto , Loi Daniela , Provini Federica , Plazzi Giuseppe , Montagna Pasquale 
Published: January 2007

AbstractRestless legs syndrome (RLS) augmentation, defined as a kind of suppression of the circadian rhythm of the disease in which sensory and motor symptoms appear earlier during the day (and over previously unaffected body parts), with a progressive phase advance until, backwards, the symptoms may cover the entire day, has been described only after treatment with dopaminergic drugs. We report clinical and polysomnographic accounts of a patient developing RLS augmentation after long‐term treatment with tramadol, an opioid agonist with selectivity for μ‐receptor and added norepinephrine and serotonin reuptake inhibition properties. Polysomnographic measures showed an improvement of RLS and a disappearance of diurnal sensory and motor RLS symptoms after tramadol was stopped. Our case confirms a recent retrospective report of augmentation of RLS after treatment with tramadol, and begs the question whether augmentation is truly restricted to dopaminergic drugs. © 2006 Movement Disorder Society
Exercise improves efficacy of levodopa in patients with Parkinson's disease
Authors: Muhlack Siegfried , Welnic Jacub , Woitalla Dirk , Müller Thomas 
Published: January 2007

AbstractThe objective was to investigate the impact of exercise on absorption and efficacy of levodopa (LD) in patients with Parkinson‘s disease (PD). A soluble, immediate release LD formulation was given followed by exercise near the aerobic limit on one day to PD patients, who underwent the same procedure only at rest on the second day. LD plasma behavior did not significantly differ between both conditions, but the motor response was significantly better 120 and 150 min after LD intake on the day with exercise than on the day with rest. Moderate exercise increases clinical efficacy of LD. © 2007 Movement Disorder Society
Triterpenoids from Eugenia grandis: structure elucidation by NMR spectroscopy
Authors: Manoharan Karuppiah Pillai , Song Fan Jing , Benny Tan Kwong Huat , Yang Daiwen 
Published: January 2007

AbstractA new pentacyclic triterpenoid, 2α,3β‐dihydroxylup‐12‐en‐28‐oic acid (1) and a rarely encountered pentacyclic triterpenoid, 3β‐hydroxylup‐12‐en‐28‐oic acid (2), together with five known compounds, friedelin (3), 3β‐friedelinol (4), betulinic acid (5), oleanolic acid (6) and β‐sitosterol (7) were isolated from the chloroform extract of stem bark of Eugenia grandis (Syn: Syzygium grande). The structure and stereochemistry of the new compound (1) and the rarely encountered compound (2) were established by 1D and 2D NMR spectroscopic techniques. All the above isolated compounds from this plant are reported for the first time. Copyright © 2007 John Wiley & Sons, Ltd.
Joint pricing, assortment, and inventory decisions for a retailer's product line
Authors: Maddah Bacel , Bish Ebru K. 
Published: January 2007

AbstractConsider a set of product variants that are differentiated by some secondary attributes such as flavor, color, or size. The retailer's problem is to jointly determine the set of variants to include in her product line (“assortment”), together with their prices and inventory levels, so as to maximize her expected profit. We model the consumer choice process using a multinomial logit choice model and consider a newsvendor type inventory setting. We derive the structure of the optimal assortment for some important special cases, including the case of horizontally differentiated items, and propose a dominance relationship for the general case that simplifies the search for an optimal assortment. We also discuss structural properties of the optimal prices. Finally, motivated by our analytical results, we propose a heuristic solution procedure, which is shown to be quite effective through a numerical study. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2007
Construction of a bipotential for a multivalued constitutive law
Authors: de Saxcé G. , Buliga Marius , Vallée C. , Lerintiu C. 
Published: January 2007

AbstractBipotentials are non smooth mechanics tools, which allows modelling various non associative multivalued constitutive laws of dissipative materials (friction contact, soils, cyclic plasticity of metals, damage).We answer the following question: given a graph M representing a material behaviour, is there a bipotential b for which M is the set of (x, y) such that b (x, y) = 〈x, y 〉? We state a simple necessary and sufficient condition for the existence of b. If it is fulfilled, we construct the bipotential. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Micromechanical strength analysis of fiber reinforced plastics
Authors: Ernst Gerald , Hühne Christian , Rolfes Raimund 
Published: January 2007

AbstractStrength of an unidirectional lamina is computed with a representative volume element. An approximative “voxel” meshing method is used in conjunction with continuum damage mechanics to simulate crack growth in the RVE. Two material models for the nonlinear material behaviour of the epoxy resin are compared. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Unit‐cell simulations of damage and failure in PRMMCs
Authors: Ertürk Serkan , Reusch Frederik , Svendsen Bob 
Published: January 2007

AbstractThe purpose of this work is damage and failure modeling in multiphase metallic materials via unit‐cell simulations and homogenization methods. To this end, we investigate such behaviour in particle‐reinforced metal matrix composites (PRMMCs). Taking into account the processes of void nucleation (due, e.g., to particle debonding and/or cracking) and growth, we examine the effect of phase composition, particle sizes and distributions, as well as the nature of the particle/matrix interface, on damage and failure in the unit cell. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Numerical Simulation of Crack Growth
Authors: Hilgert Oliver , Schröder Jörg , Löblein Joachim 
Published: January 2007

AbstractIn recent years the X‐FEM based on the partition of unity method and the strong discontinuity approach (SDA) have shown to be powerful tools to model crack growth. Both methods model the crack surface by introducing additional d.o.f.. In the X‐FEM the nodes in the mesh around a crack are globally enhanced with new d.o.f. while in in the SDA the new d.o.f. are commonly introduced as internal ones. Thus the jump displacement fields are constant across elements. Therefore the d.o.f. can be condensed on element level which results in jumps in the displacement field at element edges. In this contribution the strong discontinuity approach is used approximating the displacement jump linearly across the crack length similar as e.g. in [3]. New additional nodes of the cracked elements that lie on the element edges are introduced but are not considered as internal nodes but remain global. Thus crack path continuity is automatically given. These global d.o.f. approximate the discontinuous part of the displacement field. The sum of the aforementioned part and the continuous displacement field represent the total displacement field including a possible jump. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Modelling of composite plates including damage
Authors: Kuczma Mieczysław , Kula Krzysztof 
Published: January 2007

AbstractThe paper is concerned with the modelling and numerical simulation of fibre‐composite plates in the nonlinear range due to large strains and damage. The layer‐wise approach is applied. Each layer is treated as elastic‐brittle and assumed to be orthotropic in the local material coordinate system. The appearance of damage is controlled according to the failure criteria [1,2,3,4]. When the failure condition is satisfied, the mechanical properties of the material are modified appropriately, depending on the type of damage (fibre breakage, matrix crack, fibre‐matrix shear). We have programmed the model as a user subroutine within the ABAQUS environment and carried out a number of numerical simulations. The obtained numerical results are compared with the experimental data available in the literature [3]. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
One fragmentation procedure for brittle material cracking
Authors: Reese S. H. , Wriggers P. 
Published: January 2007

AbstractRealistic modeling of 3D fragmentation procedures with minimal incorporation of restrictions to the crack path is still a challenge in modern computational engineering simulations. The presented approach is used to model failure and cracking in concrete structures, applying an explicit finite element integration scheme. Within this model the Strong Discontinuity Approach (SDA) is used to handle the failure process until the material is fully damaged. At stage an adaptive refinement technique is incorporated in ordner to introduce real cracks which are suitable for DEM / FEM coupling or contact formulations. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
An Approach for Micromechanical Modelling of Damage Mechanisms
Authors: Timmel Mario , Kaliske Michael , Kolling Stefan 
Published: January 2007

AbstractIn the framework of numerical simulation of damaged materials, softening behaviour represents an important topic. Thereby, the decrease of stiffness is mainly caused by the evolution of microvoids. In contrast to the established phenomenological damage approaches, the explicit consideration of effects on the micro scale can lead to an improved approximation quality. In this work, we discuss an approach to describe microstructural evolution. Based on a two phase micro model representing the macroscopical material behaviour, the structural evolution on the micro scale will be modelled based on configurational forces. Besides some theoretical basics on configurational forces at two phase systems and the definition of suitable evolution laws, we present an application of this approach on void growth process in rubberlike material. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Partially connected composite beams
Authors: Kuczma Mieczysław , Kuczma Bożena 
Published: January 2007

AbstractAnalytical solutions to some boundary value problems for a steel‐concrete composite beam with deformable shear connectors in the elastic range are presented. The obtained results show that the distribution of slip on the bond interface between the concrete slab and the steel girder is not a monotone function, even in the case of uniform loading on the composite beam. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Modelling of the frictional heating generated in rolling contact
Authors: Pauk Volodymyr , Zastrau Bernd W. 
Published: January 2007

AbstractThe transformation of the frictional energy into the heating is a problem of continued technical interest. This problem in the case of the pure sliding contact is widely discussed in many papers. In the case of rolling contact, the frictional heating is due to the slip between the rollers. Since the value of slip is unknown, the problem is more complicated, it becomes non‐linear. The paper presents a new mathematical model of the generation of the heat during the rolling problem. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
An efficient strategy to lifetime calculations of large structures
Authors: Rickelt Christian , Reese Stefanie 
Published: January 2007

AbstractThe objective of this contribution is to present two single aspects of our efficient strategy to life cycle calculations of large structures. According to the assumption that only some segments of a structure require a non‐linear analysis the entire system is strictly decomposed into linear and non‐linear subsystems. To increase the efficiency further the number of degrees‐offreedom of the linear parts are treated by model reduction techniques. Three different methods are depicted and compared. To simulate the growth of damage an isotropic continuum damage model for ductile damage phenomena of metals under consideration of large inelastic strains is presented. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A comparison of nonlinear beam finite element formulations
Authors: Sänger N. , Betsch P. 
Published: January 2007

AbstractTwo alternative nonlinear finite element formulations emanating from the Simo‐Reissner beam theory are considered. The orientation of the beam cross section is characterised by a director frame which can be either represented by means of rotational parameters or the direction cosine matrix. In the planar case the use of a single angle can be considered as the canonical formulation. The corresponding finite element approximation relies on the interpolation of the nodal angles. However, the extension of this approach to the three‐dimensional case is nontrivial and often leads to element formulations beeing not frame‐indifferent. On the other hand, the interpolation of the nodal direction cosines in general yields frame‐indifferent element formulations [1, 2]. The present talk focuses on a comparison of the two aforementioned finite element beam formulations for planar problems. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Remarks on a Least Squares Mixed Finite Element for Plane Elasticity
Authors: Schwarz Alexander , Schröder Jörg 
Published: January 2007

AbstractThe objective of this work is to discuss a least squares finite element method within plane elasticity problems. The L 2‐norm minimization of the residuals of the given first order system of differential equations leads to a functional, which is a two field formulation in the displacements and the stresses. The governing equations for the considered least squares mixed finite element are derived. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Determining Mechanical State of the Body – Multilayer Coating System
Authors: Shevchuk Victor A. 
Published: January 2007

AbstractThis paper suggests an effective approach, essentially simplifying determining mechanical state of bodies with thin multilayer coatings. It is based on the modeling of such coatings by thin shells with appropriate geometrico‐mechanical properties of a coating. In such an approach, the influence of thin coatings on the mechanical state of the body ‐ multilayer coating system is described by special generalized boundary conditions. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Study on the thermo‐mechanical behavior of superelastic NiTi wires
Authors: Vishnevsky Andrey , Lammering Rolf 
Published: January 2007

AbstractThe strong coupling of thermal and mechanical properties and the highly inhomogeneous strain distribution in tensiontests motivate for thorough investigations on NiTi shape memory alloys. For these tests a complex experimental set‐up has been developed which allows for the simultaneous measurement of stress, strain, and temperature with high spatial and temporal resolution. The experimental results show the influence of strain rate, number of cycles, and deformation level on the progress of stress induced phase transformation in the specimens. A critical evaluation of the experimental results in view of a potential constitutive modeling is given. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A constitutive model for polymers with a piecewise linear yield surface
Authors: Vogler M. , Kolling S. , Haufe A. 
Published: January 2007

AbstractReliable prediction of the behaviour of structures made from polymers, especially under high dynamic loading, is a topic under considerable investigation in engineering practice. A constitutive model is derived including important phenomena like necking, crazing and strain rate dependency. In particular, different yield surfaces in compression and tension are taken into account using a piecewise linear formulation. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Freie Zielanfahrt
Authors: Barthels Pierre , Wauer Jörg 
Published: January 2007

AbstractVon “freier Zielanfahrt” spricht man in der Fördertechnik, wenn der Bewegungsablauf von Förder‐ und Hebezeugen (z.B. Gabelstapler) durch einen Menschen gesteuert wird und die Bewegung somit vorgegeben aber zufällig ist. Die hierbei auftretenden Transversalschwingungen der teleskopierbaren Segmente des Mastes reduzieren die Leistungsfähigkeit der Maschine und führen zu Sicherheitsproblemen. Dieser Beitrag befasst sich mit der Schwingungsunterdrückung bei solchen Systemen, wobei eine dem jeweiligen Systemzustand entsprechend geregelte Kraft auf das unterste Segment des Mastes aufgebracht wird. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)