bluuebunny/crossref_metadata_2025_split huggingface dataset:
Development of a Two-Dimensional Evaluation Method for Thin Layers Using Surface Plasmon Resonance
Authors: Otsuki Soichi , Murai Kensuke , Yoshikawa Susumu 
Published: April 2003

Abstract
A two-dimensional evaluation method for intermolecular interactions based on surface plasmon resonance (SPR) was developed. The measurement was conducted at varying wavelengths. The wavelength affording the minimum brightness (SPR wavelength) was determined at each pixels of the image. The spatial distribution of SPR wavelength was converted to a thickness distribution in nm scale, which well presented structures of thin materials attached on silver film.
Hydrogen Generation from Water with Nonthermal Plasma
Authors: Kabashima Hajime , Einaga Hisahiro , Futamura Shigeru 
Published: April 2003

Abstract
Nonthermal plasma chemical decomposition of water was carried out with two different types of reactors such as ferroelectric packed-bed (FPR) and silent discharge (SDR) to explore the possibility of hydrogen generation in a flow reaction system. When FPR was used, the H2 yield in this reaction reached 63% at 150 kJ L−1 of supplied specific energy density in N2. On the other hand, the H2 yield was much lower with SDR than with FPR under the same conditions.
Homo-Coupling Polycondensation of Bis(alkynylsilane)s Mediated by Copper(I) Chloride: A New Synthesis of Poly(arylenebutadiynylene)s
Authors: Nishihara Yasushi , Kato Tsuyoshi , Ando Jun-ichi , Mori Atsunori , Hiyama Tamejiro 
Published: April 2003

Abstract
Homo-coupling polycondensation of aromatic compounds bearing two (trimethylsilyl)ethynyl groups mediated by copper(I) chloride in DMF gives conjugated poly(arylenebutadiynylene)s in up to 94% yield with molecular weight of 4000–8900 (Mw/Mn = 1.78–2.09).
Methyl Sulfonium Salts of 9,9′-Bibenzonorbornenylidene Episulfides: Preparation and Isomerization
Authors: Sugihara Yoshiaki , Aoyama Yui , Nakayama Juzo 
Published: April 2003

Abstract
Methylations of bibenzonorbornenylidene episulfides 5 and 6 by Me3O+BF4− at −18 °C furnished the corresponding episulfonium salts 7 and 8, respectively, with retention of the configuration of the episulfides, whereas those at room temperature or above produced a mixture of 7 and 8 in the ratio of about 1:4. Dynamic 1H NMR investigation in the temperature range 25–40 °C allowed the determination of the activation parameters of the isomerization between 7 and 8, which obeyed first-order kinetics.
Synthesis and Redox Property of Cyclic Mixed-Metal Complexes from Diethynylbiferrocene
Authors: Mori Yukie , Kasai Takeshi , Takesada Toru , Komatsu Hiroaki , Yamazaki Hiroshi , Haga Masa-aki 
Published: April 2003

Abstract
The reaction of 6,6′-diethynylbiferrocene (1) with cis-PtCl2(PR3) (R= nBu and Me) or (η5-C5H5)Co(PR3)2 gave novel cyclic mixed metal complexes, which show a rich oxidative electrochemistry.
Unprecedented Rhodium-Mediated Tetramerization of Bulky Terminal Alkynes Leading to Hydropentalenylrhodium Complexes
Authors: Komatsu Hiroaki , Suzuki Yasunobu , Yamazaki Hiroshi 
Published: April 2003

Abstract
The reactions of bulky terminal alkynes, RC≡CH [R= tBu, 1a; Me3Si, 1b; (cod)Rh(η5-Me2C5H2), 1c] with [RhCl(cod)]2 in the presence of Et3N have been found to provide novel hydropentalenylrhodium complexes, (cod)Rh(η5-R4C8H3) (2, 4 and 5). The structures have been determined by a single-crystal X-ray diffraction analysis. A mechanism involving the migration of an α-tert-butyl group or an α-hydrogen atom of the metal–vinyl intermediates is proposed.
Sorted circles in the maritime Subantarctic, Marion Island
Authors: Holness Stephen Dale 
Published: April 2003

AbstractActive sorted circles are quantitatively described for the first time for the maritime Subantarctic. Increasing altitude and hence increasing frost penetration are associated with systematic increases in pattern spacing, cell width, height of the fine centre relative to the border, and depth of sorting (but not the width of coarse margins). These results imply consistent dimensional scaling of circle parameters. It is argued, on the basis of the altitudinal trends in pattern morphology, the dimensional scaling of forms, and the morphology of the patterns, that differential frost heave in association with convection cells is responsible for circle formation. Copyright © 2003 John Wiley & Sons, Ltd.
Processes and rates of sediment and wood accumulation in headwater streams of the Oregon Coast Range, USA
Authors: May Christine L. , Gresswell Robert E. 
Published: April 2003

AbstractChannels that have been scoured to bedrock by debris flows provide unique opportunities to calculate the rate of sediment and wood accumulation in low‐order streams, to understand the temporal succession of channel morphology following disturbance, and to make inferences about processes associated with input and transport of sediment. Dendrochronology was used to estimate the time since the previous debris flow and the time since the last stand‐replacement fire in unlogged basins in the central Coast Range of Oregon. Debris flow activity increased 42 per cent above the background rate in the decades immediately following the last wildfire. Changes in wood and sediment storage were quantified for 13 streams that ranged from 4 to 144 years since the previous debris flow. The volume of wood and sediment in the channel, and the length of channel with exposed bedrock, were strongly correlated with the time since the previous debris flow. Wood increased the storage capacity of the channel and trapped the majority of the sediment in these steep headwater streams. In the absence of wood, channels that have been scoured to bedrock by a debris flow may lack the capacity to store sediment and could persist in a bedrock state for an extended period of time. With an adequate supply of wood, low‐order channels have the potential of storing large volumes of sediment in the interval between debris flows and can function as one of the dominant storage reservoirs for sediment in mountainous terrain. Copyright © 2003 John Wiley & Sons, Ltd.
On evolution of bed material waves in alluvial rivers
Authors: Cao Zhixian , Carling Paul A. 
Published: April 2003

AbstractField and laboratory measurements have shown distinct characteristics of bed sediment waves under differing conditions, whilst their theoretical interpretation has emerged to be equivocal. This note aims to clarify the interpretation of evolution of bed material waves. The complete set of governing equations for the flow–sediment–morphology system is deduced to demonstrate its universally hyperbolic nature, irrespective of the sediment transport functions implemented to close the equations. The hyperbolic nature can admit not only attenuating bed material waves, but also shock‐like waves that are not unusual in the real world. It is suggested that the theory of dispersion/diffusion is not universally appropriate for evolution of bed material waves. Copyright © 2003 John Wiley & Sons, Ltd.
Hydrophilic Films Based on Blends of Poly(acrylic acid) and Poly(2‐hydroxyethyl vinyl ether): Thermal, Mechanical, and Morphological Characterization
Authors: Khutoryanskiy Vitaliy V. , Cascone Maria Grazia , Lazzeri Luigi , Barbani Nicoletta , Nurkeeva Zauresh S. , Mun Grigoriy A. , Bitekenova Asem B. , Dzhusupbekova Aizhana B. 
Published: April 2003

AbstractHydrophilic films based on blends of poly(acrylic acid) and poly(2‐hydroxyethyl vinyl ether) were prepared by casting. The characterization of the films was performed by differential scanning calorimetry (DSC), dynamic mechanical thermal analysis (DMTA), and scanning electron microscopy (SEM). It was shown that an increase of poly(2‐hydroxyethyl vinyl ether) content in the blends considerably decreases the glass transition temperature of the samples. The films containing 10 and 20 mol‐% of poly(2‐hydroxyethyl vinyl ether) show behavior of polymers in the glassy state, but a further increase of nonionic polymer content in the blend (30–50 mol‐%) provides the mechanical properties typical of a rubbery state. The content of water traces in the films has a significant effect on the mechanical properties of the materials.Normalized DSC thermograms of PAA:PHEVE films. [PAA]:[PHEVE] = 90:10 (1), 80:20 (2), 70:30 (3), 60:40 (4), 50:50 mol‐% (5).magnified imageNormalized DSC thermograms of PAA:PHEVE films. [PAA]:[PHEVE] = 90:10 (1), 80:20 (2), 70:30 (3), 60:40 (4), 50:50 mol‐% (5).
Generalization of Kähler angle and integral geometry in complex projective spaces II
Authors: Tasaki Hiroyuki 
Published: April 2003

AbstractIn a previous paper the author has generalized the Kähler angle to the multiple Kähler angle and formulated a Poincaré formula for any real submanifolds in complex projective spaces ℂPn using the multiple Kähler angles of the submanifolds. In this paper we formulate a Poincaré formula for submanifolds M and N of complementary dimension in ℂPn by a symmetric polynomial of degree one in cos2 θi and cos2 τj, where θi and τj are the multiple Kähler angles of M and N. We also obtain some inequalities between the integral of the intersection numbers of submanifolds and their volumes in some cases.
Architecture of Polymeric Superstructures Constructed by Mesoscopically Ordered Cubic Lattices
Authors: Ishizu Koji 
Published: April 2003

AbstractHighly monodisperse crosslinked core‐shell polymer microspheres could be prepared easily by introducing special crosslinking reagents into the segregated core in block copolymer assembly films. The crosslinked core was stabilized sterically by highly branched shell chains in solution. These microspheres moved like pseudo‐latex. The microspheres formed a lattice with a body‐centered cubic (BCC) structure near the overlap threshold (C*). This structure changed to a face‐centered cubic (FCC) lattice in the bulk region of the films. Photofunctionalized core‐shell microspheres were prepared by introducing dithiocarbamate (DC) groups into shell parts by means of polymer reactions, where DC groups could be propagated using vinyl monomers such as methyl methacrylate (MMA) with living radical mechanism. Polymeric superstructure (three microphase‐separated structure) films were constructed by graft copolymerization of MMA initiated with photofunctionalized microspheres such as macroinitiators under UV irradiation, exhibiting self‐coloring due to Bragg diffraction. These materials can be used for the construction of optical devices such as for the fabrication of light modulators.
Photograph of a solution of the microsphere in MMA.magnified imagePhotograph of a solution of the microsphere in MMA.
Potentials and Limitations of Automated Parallel Emulsion Polymerization
Authors: Voorn Dirk‐Jan , Fijten Martin W. M. , Meuldijk Jan , Schubert Ulrich S. , van Herk Alex M. 
Published: April 2003

AbstractThe application of automated parallel synthesizer robots for the investigation of polymerization processes is of major interest at present. In this contribution we describe the application of the emulsion polymerization of styrene and vinyl acetate. The preparations of emulsions and latexes were investigated in detail and compared to “conventional” stirred tank reactors. In particular the influence of the vortex mixing as well as the limitations regarding solid content and reactor fouling are addressed.
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Enhancement of Photostability in Blue‐Light‐Emitting Polymers Doped with Gold Nanoparticles
Authors: Park Jong Hyeok , Lim Yong Taik , Park O Ok , Kim Young Chul 
Published: April 2003

AbstractA dramatic increase in the photostability of a blue‐light‐emitting polymer, poly(9,9‐dioctylfluorene), was achieved by the addition of 5–10 nm gold nanoparticles. The optical absorption band of the gold nanoparticles was tuned to resonate the triplet exciton ground state bandgap energy of the polymer. Photo‐oxidation rate of poly(9,9‐dioctylfluorene) was effectively reduced by doping the polymer with very small amounts (≈10−6–10−5 volume fraction) of the gold nanoparticles.Retarded photo‐oxidation in PDOF nanocomposite films with various doped gold nanoparticles.magnified imageRetarded photo‐oxidation in PDOF nanocomposite films with various doped gold nanoparticles.
Time–accurate Modular CFD‐CSD Coupling for Aeroelastic Rotor Simulations
Authors: Altmikus A. , Wagner S. 
Published: April 2003

AbstractThis paper addresses the timewise accuracy of different coupling approaches applied to instationary aeroelastic simulations of rotors in forward flight. Two different approaches which are widely discussed in literature are examined: the tight or strong coupling, and the fully integrated or monolithic coupling.Strong coupling means an exchange of fluid loads and structural deformations at each time step which is effectuated in a fully modular manner. We will address aspects of conservativity and time‐accuracy, and will present results for a helicopter forward flight scenario. However, objections concerning the correct solution of the global non‐linear three field problem – structure, grid deformation, aerodynamics – remain.These objections are normally rejected by the monolithic approach. Here, a common set of partial differential equations is derived and solved in a single code. However, a truly monolithic system of equations is only needed for stability analysis, and it can be decomposed in a three field problem respecting appropriate boundary conditions for each domain. Thus, modularity can be maintained, conceiving a quasi‐monolithic procedure, when both domains are simultaneously solved in a common non‐linear iteration loop on a per time‐step basis. First results will be shown for a 2D flutter testcase.
Automatic Differentiation for MATLAB Programs
Authors: Bischof Christian , Lang Bruno , Vehreschild Andre 
Published: April 2003

AbstractDerivative information is required in numerous applications, including sensitivity analysis and numerical optimization. For simple functions, symbolic differentiation–done either manually or with a computer algebra system–can provide the derivatives, whereas divided differences (DD) have been used traditionally for functions defined by (potentially very complex) computer programs, even if only approximate values can be obtained this way. An alternative approach for such functions is automatic differentiation (AD), yielding exact derivatives at often lower cost than DD, and without restrictions on the program complexity. In this paper we compare the functionality and describe the use of ADMIT/ADMAT and ADiMat. These two AD tools provide derivatives for programs written in the MATLAB language, which is widely used for prototype and production software in scientific and engineering applications. While ADMIT/ADMAT implements a pure operator overloading approach of AD, ADiMat also employes source transformation techniques.
A Note on a Nonlinear Model of a Piezoelectric Rod
Authors: Gausmann R. , Seemann W. 
Published: April 2003

AbstractIf piezoceramics are excited by weak electric fields a nonlinear behavior can be observed, if the excitation frequency is close to a resonance frequency of the system. To derive a theoretical model nonlinear constitutive equations are used, to describe the longitudinal oscillations of a slender piezoceramic rod near the first resonance frequency. Hamilton's principle is used to receive a variational principle for the piezoelectric rod. Introducing a Rayleigh Ritz ansatz with the eigenfunctions of the linearized system to approximate the exact solution leads to nonlinear ordinary differential equations. These equations are approximated with the method of harmonic balance. Finally it is possible to calculate the amplitudes of the displacements numerically. As a result it is shown, that the Duffing type nonlinearities found in measurements can be described with this model.
One‐parametric families of canard cycles: two explicitly solvable examples
Authors: Schneider Klaus R. , Shchetinina Ekaterina V. 
Published: April 2003

AbstractSystems of singularly perturbed autonomous ordinary differential equations possessing in a parameter plane two intersecting bifurcation curves connected with the generation of limit cycles with large and small amplitude respectively, have a special class of limit cycles called canards or french ducks describing an exponentially fast transition from a small amplitude limit cycle to limit cycle with a large amplitude. We present two explicitly integrable examples of non‐autonomous singularly perturbed di.erential equations with canard cycles without a second parameter.
Stabilitätsanalysen für schwingende Seile
Authors: Thalheim J.‐U. , Heinen A. H. 
Published: April 2003

AbstractBei Seilkonstruktionen (z.B. abgespannte Maste, Schrägseilbrücken) sind einige unerwartete Schwingungs‐ und Instabilitätsphänomene aufgetreten, wie z.B. Regen/Wind‐induzierte und parametererregte Schwingungen, siehe [1] und Bild 3. Ausgehend von den nichtlinearen Seilgleichungen werden diese mittels des Prinzips der virtuellen Verrückungen (PdV) in eine FE‐Formulierung überführt, aus der auf der Basis des Ljapunowschen Kriteriums kinetische Stabilitätsgleichungen gewonnen werden, die auf ein Seil unter hamonischer Auflagerbewegung angewendet werden, da so z.B. die Wirkung von Pylonbewegungen auf die Seile von Schrägseilbrücken abgeschätzt werden kann.
Ein Zeitschrittverfahren für mechanische Schwingungssysteme mit fraktionalen Ableitungen
Authors: Wagner Nils 
Published: April 2003

AbstractSysteme mit nachlassendem Gedächtnis werden sowohl mit dem Konzept Innerer Variablen als auch mit dem der fraktionalen Ableitungen beschrieben. Startpunkt ist hier die Liouville‐Riemann Definition der fraktionalen Ableitung. Auf der Basis quadratischer Ansatzfunktionen für das Verschiebungs‐ und Geschwindigkeitsfeld wird ein Zeitschrittverfahren entwickelt.
Nichtholonome Bindungen und Systeme
Authors: Braun Manfred 
Published: April 2003

AbstractEin mechanisches System, das einer nochtholonomen kinematischen Bindung unterliegt, kann dennoch als ganzes holonom sein. Dies wird am Beispiel eines ebenen Verfolgerproblems demonstriert. Die Verfolgerbedingung ist zwar nichtholonom, sie wird aber durch eine weitere kinematische Bedingung ergänzt, die beispielsweise das Verhältnis der Geschwindigkeiten von Ziel und Verfolger festlegt. Die Verfolgerbedingung kann dann durch eine holonome Linearkombination der beiden kinematischen Bindungen ersetzt werden. Das Gesamtproblem ist also holonom, obwohl in der ursprünglichen Formulierung eine der beiden kinematischen Bindungen nichtholonom war.
Dynamic Aspects in Satellite Capturing by Robotic Manipulator
Authors: Rebele B. , Schäfer B. , Lopez‐Doriga D. B. 
Published: April 2003

AbstractSince several years the interest in offering satellite services for maintenance and repair of malfunctioned satellites is strongly increasing. Currently, a very typical and actual application is dedicated to the rescue of a defect satellite (Rosat) in low earth orbit by means of a servicer satellite based manipulator [1]. The dynamic aspects are carefully considered in order to minimize both, the strong vibrational behavior of the combined satellite system, and the mechanical stresses in the slender boom and the robotic joints and arm structure, and consequently, to find the optimal capturing strategy.
Elastic–plastic buckling of annular circular plate with linear material hardening
Authors: Bremec B. , Kosel F. , Petrišič J. 
Published: April 2003

AbstractThe contribution treats the buckling problem of a circular annular plate where the unstable state and the buckling process occurs when the stress state in the most loaded points of the plate is already in the elastic–plastic region. It is supposed that the plate buckles axisymmetrically (m = 0) or nonaxisymmetrically with m > 0, m ∈ ℕ waves in the circumferential direction. Using the equilibrium method, the critical buckling loads are calculated. The results show the influence of the material hardening coefficient 0 ≤ f ≤ 1 on the buckling load. The comparison between calculations with the consideration of flow and deformation theory of plasticity is given.
Stress and deformation states in the annulus made from shape memory material
Authors: Kosel F. , Videnic T. 
Published: April 2003

AbstractThe contribution deals with the stress and deformation states in an annulus made of shape memory material (SMM). The loading‐unloading process is going on at constant temperature, which is below temperature Mf (martensite finish temperature). The research is focused on the determination of the stress and deformation states in the annulus after loading and unloading process. These results are necessary for treating process of constrained recovery in shape memory annulus. The real loading‐unloading function in the stress‐strain coordinate system of shape memory material (Ni–Ti–Cu) is included in the mathematical model.
Randelementmethoden zur elektromechanischen Festigkeitsanalyse piezoelektrischer Strukturen
Authors: Groh U. 
Published: April 2003

AbstractZur Untersuchung der Zuverlässigkeit piezokeramischer Konstruktionselemente bei mechanisch‐elektrischer Belastung werden u.a. Intensitätsfaktoren herangezogen, die die Singularität der Felder des elektro‐elastischen Problems an Rissspitzen charakterisieren. Für die Lösung der entsprechenden zweidimensionalen Randwertaufgabe wurde ein bezüglich Geometrie, Material und Randbedingungen flexibles Kollokations‐Randelementverfahren entwickelt, das Singularitäten an Rissspitzen mit singulären Randelementen erfasst. Bereits mit wenigen Randelementen ist eine relativ hohe Genauigkeit der berechneten Intensitätsfaktoren erzielbar.
A Shortcoming in the Geometrically Non‐Linear Shakedown Theorem
Authors: Schieck B. 
Published: April 2003

AbstractThe original static shakedown theorem of Melan [1], valid for geometrically linear theory, was extended for geometrically non‐linear theory e.g. by Polizzotto and Borino [2], who presented a proof for large rotations with small strains. However, a counterexample to this extended Melan's theorem has been found. The reason of the failure is investigated and is corrected by an additional condition in the theorem. The outline of the proof is given.
Finite Element Modelling of Cracks Based on the Partition of Unity Method
Authors: Dumstorff P. , Meschke G. 
Published: April 2003

AbstractIn this paper a finite element model for the analysis of brittle materials in the post cracking regime is presented. The model allows the representation of failure zones several times smaller than the structure itself using relatively coarse finite element meshes. The formulation is based on the partition of unity method. Discontinuous shape functions are used to enrich the continuous approximation of the displacement field where a crack has opened [2]. The magnitude of the displacement jump is determined by extra degrees of freedom at existing nodes. The crack path is completely independent of the structure of the mesh and is continuous across element boundaries. To model inelastic deformations around the crack tip a cohesive crack model is used. A representative numerical example illustrates the performance of the proposed model.
Simulation of bone modeling around a screw implant in the mandible
Authors: Rong Q. , Lenz J. , Schweizerhof K. , Schindler H.J. , Riediger D. 
Published: April 2003

AbstractOn the basis of a biomechanical model for the bone healing process around a dental implant, the attainable degree of ossification in two‐phase implantation is studied for a screw implant and compared with corresponding results for a cylinder implant. It is shown that a screw implant delivers a better ossification of the repair zone than a cylinder implant which is in accordance with clinical observation.