bluuebunny/crossref_metadata_2025_split huggingface dataset:
HORSESHOES IN THE TWIST-AND-FLIP MAP
Authors: BROWN RAY , CHUA LEON 
Published: November 2004

We derive an analytical relationship between the parameters of a square-wave forced, nonlinear, two-dimensional ordinary differential equation which determines conditions under which the Poincaré map has a horseshoe. This provides an analytical test for chaos for this equation. In doing this we show that the Poincaré map has a closed-form expression as a transformation of R2 of the form FTFT, where F is a flip, i.e., a 180-degree rotation about the origin and T is a twist centered at (a, 0) for a > 0. We show that this derivation is quite general. We aiso show how to relate our results to ODEs with continuous periodic forcing (e.g., the sinusoidal-forced Duffing equation). Finally, we provide a conjecture as to a sufficient condition for chaos in square-wave forced, nonlinear ODEs.
PERIODIC INHIBITION OF LIVING PACEMAKER NEURONS (I): LOCKED, INTERMITTENT, MESSY, AND HOPPING BEHAVIORS
Authors: SEGUNDO J. P. , ALTSHULER E. , STIBER M. , GARFINKEL A. 
Published: November 2004

This communication is concerned with an embodiment of periodic nonlinear oscillator driving, the synaptic inhibition of one spike-producing pacemaker neuron by another. Data came from a prototypical living synapse. Analyses centered on a prolonged condition between the transients following the onset and cessation of inhibition. Evaluations were guided by point process mathematics and nonlinear dynamics. A rich and exhaustive list of discharge forms, described precisely and canonically, was observed across different inhibitory rates. Previously unrecognized at synapses, most forms were identified with several well known types from nonlinear dynamics. Ordered by decreasing regularities, they were locked, intermittent (including walk-throughs), messy (including erratic and stammerings) and hopping. Each is discussed within physiological and formal contexts. It is conjectured that (i) locked, intermittent and messy forms reflect limit cycles on 2-tori, quasiperiodic orbits and strange attractors, (ii) noise in neurons hovering around threshold contributes to certain intermittent and stammering behaviors, and (iii) hopping either reflects an attractor with several portions or is nonstationary and noise-induced.
SEMIGROUPS WITH IDEMPOTENT STABILIZERS AND APPLICATIONS TO AUTOMATA THEORY
Authors: LE SAEC BERTRAND , PIN JEAN-ERIC , WEIL PASCAL 
Published: November 2004

Nous prouvons que tout semigroupe fini est quotient d'un semigroupe fini dans lequel les stabilisateurs droits satisfont les identités x = x2 et xy = xyx. Ce resultat a plusieurs consé-quences. Tout d'abord, nous l'utilisons, en même temps qu'un résultat de I. Simon sur les congruences de chemins, pour obtenir une preuve purement algébrique d'un théorème profond de McNaughton sur les mots infinis. Puis, nous donnons une preuve algébrique d'un théorème de Brown sur des conditions de finitude pour les semigroupes. We show that every finite semigroup is a quotient of a finite semigroup in which every right stabilizer satisfies the identities x = x2 and xy = xyx. This result has several consequences. We first use it together with a result of I. Simon on congruences on paths to obtain a purely algebraic proof of a deep theorem of McNaughton on infinite words. Next, we give an algebraic proof of a theorem of Brown on a finiteness condition for semigroups.
UPPER BOUNDS AND APPROXIMATION FOR THE SOLUTION OF A NONLINEAR PARTICLE TRANSPORT PROBLEM WITH MAXWELL TYPE BOUNDARY CONDITIONS
Authors: TOTARO SILVIA 
Published: November 2004

We consider a nonlinear particle transport problem in a slab of thickness 2a with Maxwell-type boundary conditions. The nonlinearity is due to the presence of a scattering term, which is a quadratic function of the (unknown) particle density u(t)=u(x, y; t). We first prove that, under suitable assumptions, the integral version of the transport equation has a unique strongly continuous solution u=u(t)∈L1∩L∞, defined over an arbitrary fixed time interval [0, t0]. We also evaluate upper bounds for the norms ||u(t)|| and ||u(t)||∞, which are useful to understand the mathematical and the physical properties of the particle transport problem under consideration. Finally, we discretize the angle variable y in the unknown function u(t)=u(x, y; t), (i.e., we use the “discrete ordinate method”) and we prove the convergence of the discretized solution to the exact solution by using a generalization of Trotter’s theory on sequences of Banach spaces approximating a given Banach space.
DOMAIN DECOMPOSITION APPROXIMATION TO A GENERALIZED STOKES PROBLEM BY SPECTRAL METHODS
Authors: CARLENZOLI CLAUDIO , ZANOLLI PAOLA 
Published: November 2004

We consider here the approximation of a generalized Stokes problem by spectral methods in the collocation form. This problem is of particular interest when Navier-Stokes equations for viscous compressible flows are investigated. We also analyze a coupling of a viscous model with an inviscid one; precisely, we split the computational domain in two parts and in one of them we eliminate the viscous coefficient from the Stokes equations. Such an approach can be worthwhile in the study of compressible fluids around rigid profiles with critical layers. Finally we consider some numerical results with the aim of showing the excellent accuracy of the spectral approximations, as well as the efficiency of an iterative algorithm that we propose in order to alternate viscous and inviscid numerical solvers.
EXPONENTIAL STABILITY OF STATIONARY SOLUTIONS TO THE DISCRETE BOLTZMANN EQUATION IN A BOUNDED DOMAIN
Authors: KAWASHIMA SHUICHI 
Published: November 2004

Large-time behavior of solutions of the discrete Boltzmann equation in a bounded domain is studied. The boundary conditions considered are pure diffuse relection and general reflection. Under suitable assumptions it is proved that a unique solution exists globally in time and converges to the corresponding unique stationary solution exponentially as time goes to infinity. The crucial point of the proof is in the derivation of desired boundary estimates of the solution subordinate to the general reflection.
AN INVESTIGATION OF THE RELATIONSHIP BETWEEN A FIRM'S PERCEIVED EXPORT BARRIERS AND STAGES OF EXPORT DEVELOPMENT: AN ANALYSIS OF CANTERBURY MANUFACTURING FIRMS
Authors: DEAN DAVID , GAN CHRISTOPHER , MYERS CHRISTOPHER 
Published: November 2004

Export continues to have positive impact on a country's economy and the economic success of the firms involved. As a result, export expansion and development programs are commonly undertaken to help firms initiate or expand export activities. The objectives of such programs are to provide firms with the opportunities, incentives, information, and resources required to exploit exporting opportunities. Research on export behaviour suggests that differentiating firms by their stage of export development is one of the effective ways of grouping firms for export development intentions. However, little research has focused on the correlation between export barriers and exporting stages. This research analyses the relationship between a firm's comprehension of export and its stage of export development based on a group of Canterbury manufacturing firms. The results identify two types of export barriers; those that were stable across stages of export development and those which changed in their level of importance across the stages.
Recording Procedures and Legal Culture In the Late Ottoman Shari'a Court Of Jaffa, 1865-1890
Authors: Agmon Iris 
Published: November 2004

AbstractIn the 1870s, a new procedure for recording cases in the shari'a courts was officially introduced by the Ottoman judicial administration. In this essay I explore the implementation of this innovation in the Jaffa court between the years 1865 and 1890. My sources include the Jaffa court records and the Ottoman regulations that specify the instructions about the new recording procedure. I argue that the court of Jaffa was a site of ongoing changes that were part of its legal culture. The judges and court scribes were regularly involved in creating new recording practices through trial and error. Thus, legal reform, from the perspective of the Jaffa court, was not the exclusive domain of the imperial center. The local court played an active role in it.
Literacy, Gender, and Class: Nüshu and Sisterhood Communities In Southern Rural Hunan
Authors: Liu Fei-Wen 
Published: November 2004

AbstractIn this article, I investigate how peasant women in Jiangyong County of southern Hunan defined and practiced a female-specific written script known as nüshu ('female writing'). With an emphasis on sisterhood relationships, I explore how women employed nüshu to construct meaning, experience autonomy, and acknowledge the androcentric impositions made upon them, which in turn highlights the dual nature of nüshu literacy. On the one hand, nüshu empowered women by allowing them to expand female connections beyond the confines of male-derived familial ties and village boundaries; on the other hand, it embodied Jiangyong peasant women's frustration over their failure to sustain such connections after marriage. To contrast nüshu with the gentry women's literary communities in the Lower Yangzi region during late imperial China, this research demonstrates how literacy dynamically interacts with the social forces of gender and class. Whereas female literati's social networks were able to expand and be sustained and even succeeded in penetrating male scholarly circles, nüshu sisterhood communities often failed to survive in face of the challenges set by village exogamy, mainly due to the lack of male support and to Jiangyong's rural context.
Fe-Rich Clays in a Weathering Profile Developed from Serpentinite
Authors: Caillaud J. , Proust D. , Righi D. , Martin F. 
Published: November 2004

AbstractBulk mineralogical and chemical properties of a weathering profile derived from serpentinite were studied using classical pedological methods (Munsell soil colors, particle-size distribution, density, cation exchange capacity, exchangeable bases, among others) and inductively coupled plasma-atomic emission spectroscopy (ICP-AES) results. Bulk clay fractions were characterized using X-ray diffraction, thermal analysis, electron microprobe, Mössbauer and infrared spectroscopies. Bulk geochemical mass-balance calculated from ICP-AES results shows leaching of both Mg and Si which reflects the early weathering of serpentine minerals. As a consequence, newly formed clay minerals are enriched with the least mobile elements, i.e. Fe and Al, producing dioctahedral smectites. These dioctahedral smectites are complex, heterogeneous and consist mainly of two populations. One population is an Fe-rich montmorillonite with little or no tetrahedral charge and Fe3+ as the dominant octahedral cation whereas the second population exhibits tetrahedral charge. Both populations occur as interstratified layers in the lower horizon of the weathering profile but show increasing segregation into well-defined end-members towards the surface horizons. Considering total Al and Fe contents, these clays differentiate into two chemical composition domains, Fe-rich clays in the lower profile and Al-rich clays towards the surface horizons.
Effects of Pyrogallol on Al13 Tridecamer Formation And Humification
Authors: Krishnamurti G. S. R. , Wang M. K. , Huang P. M. 
Published: November 2004

AbstractThe Al13 polycation is the predominant hydroxy-Al species in partially neutralized solutions. However, the existence of the Al13 species and the factors governing its formation in terrestrial environments still remain obscure. The objective of this study was to investigate the influence of pyrogallol, a common polyphenol in soils, on the formation of Al13 tridecamer. Hydroxy-Al solutions with an OH/Al molar ratio of 2.2 (pH 4.53) at pyrogallol/Al molar ratios of 0, 0.01, 0.05, 0.1 and 0.5 were prepared and mixed with 0.5 M sodium sulfate to form aluminum sulfate precipitation products. The solid-state 27Al nuclear magnetic resonance (NMR) spectra of the precipitates show that the pyrogallol perturbed the formation of Al13 tridecamer species as indicated by the decrease in the intensity of resonance peak, observed at 62.5 ppm, with increase in the pyrogallol/Al molar ratio. The crystallization of the precipitated Al sulfates was also hampered by pyrogallol, resulting in the formation of X-ray non-crystalline products at a pyrogallol/Al molar ratio of 0.50. The absorbance at 465 and 650 nm of the hydroxy-Al-pyrogallol solutions, the C coprecipitated, the electron spin resonance and 13C CPMAS-NMR spectra of the precipitates indicate the concomitant enhanced abiotic humification of pyrogallol by the X-ray amorphous Al species.
Adsorption and Photo-reactivity of Bensulfuron-Methyl On Homoionic Clays
Authors: Si Youbin , Wang Shenqiang , Zhou Dongmei , Chen Huaiman 
Published: November 2004

AbstractThe adsorption and photolysis of the herbicide bensulfuron-methyl [2-(4, 6-dimethoxypyrimidm-2-carbamoylsulfamoyl)-o-toluic acid methyl ester] on homoionic Na+-, Ca2+- and Fe3+-montmorillonite and kaolinite clays were studied. The Freundlich adsorption coefficient, Kf, measured from isotherms on clays followed the order Na+ < Ca2+ < Fe3+. Montmorillonite showed a greater adsorptive capacity than kaolinite. Analysis of Fourier transform infrared spectra of bensulfuron-methyl adsorbed on clay suggested probable bonding interactions between bensulfuron-methyl and homoionic clays. The photolysis rate of herbicide adsorbed on homoionic clay surfaces was quite slow to its free state and decreased in the order Na+ > Ca2+ > Fe3+, indicating that adsorption may have prevented photolysis.
Dickite and Other Kaolin Polymorphs from an Al-rich Clay Deposit Formed in Volcanic Tuff, Southeastern Korea
Authors: Choo Chang Oh , Kim Soo Jin 
Published: November 2004

AbstractKaolins from an Al-rich clay deposit formed in volcanic tuff, southeastern Korea contain predominant dickite and quartz with accessory diaspore, pyrophyllite, alunite, illite, sulfides and calcite. Intergrowth of blocky crystals with thin ones within stacks suggests that blocky crystals gradually replaced thin ones within the same stacks. Numerous dickite plates with pseudo-hexagonal outline are placed in rows eventually forming a U-shaped stack and a vermiform stack. Individual crystals within the stack are of pseudo-hexagonal form and vermiform, accompanying slips across basal planes. The euhedral dickite with blocky habit has basal planes (001) and edge planes (110) perpendicular to each other, and it shows pseudo-hexagonal crystallites elongated in one direction. Fourier transform infrared spectra at OH-stretching and far-infrared regions show that the dickitic mass contains a small proportion of kaolinite or nacrite, indicating interstratification or at least mixtures of kaolin polytypes. The formation of mixtures of various polytypes that are of kaolinite-dickite, dickite and mixtures of dickite-nacrite could be attributed to hydrothermal processes ranging over a broad spectrum of temperature and fluid chemistry.
The Reduction of 2,6‐Dimethoxy‐4‐chloro‐1,3,5‐triazine on Mercury Electrodes in Aqueous Solutions in Relation with the Reduction of s‐Triazine Herbicides
Authors: Rodríguez Mellado J. M. , Ruiz Montoya M. , Galvín R. Marín 
Published: November 2004

AbstractThis paper presents polarographic and voltammetric studies on the electroreduction of 2,6‐dimethoxy‐4‐chloro‐1,3,5‐triazine on mercury electrodes in aqueous solutions and in the acidity range 2 M H2SO4 to pH 7. Above pH 6.5 no signals were obtained. In both DC and DP polarography and voltammetry, one or two partially overlapped reduction waves were observed, depending on the pH of the medium. The overall process corresponded to a four‐electron irreversible reduction. In strongly acidic media (pH<4.5) the protonated reactant was reduced through a two‐electron process to give a dechlorinated molecule that is subsequentely reduced at the potentials of the second wave. It was concluded that the reduction of the chlorinated s‐triazine rings seems to occur through the reductive cleavage of the chlorine irrespective of the nature of the groups bonded to the ring in positions 2, 6.
Facile Synthesis of a Degradable Gel by Radical Copolymerization of Vinyl Sorbate and Molecular Oxygen
Authors: Taketani Shuji , Matsumoto Akikazu 
Published: November 2004

AbstractSummary: A new kind of degradable gel was prepared by radical copolymerization of vinyl sorbate (VS) with molecular oxygen. A soluble and linear copolymer was produced at the initial stage of the polymerization and the ratio of the gel fraction was rapidly increased in the process of polymerization. An analysis of the polymerization by near infrared (NIR) spectroscopy strongly suggests that the conjugated diene group is much more reactive than the vinyl ester group. The degradation of an insoluble part (VS‐gel) was investigated by thermogravimetric (TG) and differential thermal analyses (DTA). Thermal degradation exothermically occurred around 110 °C. The weight loss of the gel was simultaneously observed. The VS‐gels obtained from polymerizations at various monomer concentrations had different physical properties, but similar degradation properties. The higher the VS monomer concentration in the feed, the lower the swelling ratio of the obtained gels due to an increase in a crosslinking density. The degradation of the VS‐gel under several stimuli other than heating was also investigated.
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The constructive completion of the space 𝒟(ℝ)
Authors: Yoshida Satoru 
Published: November 2004

AbstractWe prove in the framework of Bishop's constructive mathematics that the sequential completion \documentclass{article}\usepackage{amssymb}\pagestyle{empty}\begin{document}$ \tilde {\cal D} $\end{document}(ℝ) of the space 𝒟(ℝ) is filter‐complete. Then it follows as a corollary that the filter‐completeness of 𝒟(ℝ) is equivalent to the principle BD‐ℕ, which can be proved in classical mathematics, Brouwer's intuitionistic mathematics and constructive recursive mathematics of Markov's school, but does not in Bishop's constructive mathematics. We also show that \documentclass{article}\usepackage{amssymb}\pagestyle{empty}\begin{document}$ \tilde {\cal D} $\end{document}(ℝ) is identical with the filter‐completion which was provided by Bishop. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Polynomial induction and length minimization in intuitionistic bounded arithmetic
Authors: Moniri Morteza 
Published: November 2004

AbstractIt is shown that the feasibly constructive arithmetic theory IPV does not prove (double negation of) LMIN(NP), unless the polynomial hierarchy CPV‐provably collapses. It is proved that PV plus (double negation of) LMIN(NP) intuitionistically proves PIND(coNP). It is observed that PV + PIND(NP ∪ coNP) does not intuitionistically prove NPB, a scheme which states that the extended Frege systems are not polynomially bounded. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Reflection z‐scan measurements of opaque semiconductor thin films
Authors: Ganeev R. A. , Ryasnyansky A. I. 
Published: November 2004

AbstractWe studied the nonlinear refraction of semiconductor thin films (3As2S3/As2Se3 and CdS) at the wavelength of 532 nm using the reflection z‐scan technique (RZ‐scan). The values of nonlinear refractive indices γ of 3As2S3/As2Se3 and CdS were calculated to be 5 × 10–10 cm2 W–1 and –5.2 × 10–11 cm2 W–1. The comparison of RZ‐scans and transmission z‐scans was carried out for CdS film. The sign of nonlinear refraction of these chalcogenides was discussed in the framework of Kramers–Kronig transformations. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Spectroscopic study of decontaminated corroded carbon steel surfaces
Authors: Eng C. W. , Halada G. P. , Francis A. J. , Dodge C. J. 
Published: November 2004

AbstractRemoval of uranium from contaminated carbon steel surfaces by chelation with hydroxycarboxylic acid has been tested as a cleaning process for decommissioning and decontaminating contaminated surfaces. Comparison of contaminated surfaces prior to decontamination with subsequently cleaned surfaces was done in order to study the effectiveness of this cleaning technique. This was accomplished using various spectroscopic techniques, including x‐ray photoelectron spectroscopy, synchrotron infrared microspectroscopy, Rutherford backscattering spectroscopy and scanning electron microscopy/energy‐dispersive spectroscopy. Mild carbon steel (1010) coupons were exposed to uranyl nitrate solution, which led to the formation of a lightly corroded surface. Some contaminated samples underwent further cyclic humidity treatment, during which additional corrosion took place. In this study, it was found that a citric acid–hydrogen peroxide–citric acid cleaning method successfully removed uranium in lightly corroded areas. However, the method but incompletely decontaminated some heavily corroded areas where more highly crystallized corrosion products are found or where complex surface structure can occlude contaminants. Use of complementary analytical techniques is essential to provide an accurate model of surface chemistry before and after decontamination. Copyright © 2004 John Wiley & Sons, Ltd.
Stress concentration around a hyperboloidal notch under tension in a magnetoelectroelastic material
Authors: Wu X.‐H. , Shen Y.‐P. , Wang X. 
Published: November 2004

AbstractA transversely isotropic magnetoelectroelastic medium made of piezoelectric BaTiO3 and magnetostrictive CoFe2O4 is bounded by a single sheeted hyperboloid of revolution which is traction, electric charges, and magnetic charges free. This solid is subjected to a finite tensile force and electric and magnetic charges at infinity. A closed‐form solution based upon the potential functions approach is obtained. The present solutions include all the solutions, such as piezoelectric, piezomagnetic, magnetostrictive, and purely elastic solutions, as special cases. Numerical examples of the tensile stress at the narrowest section are presented and show that the stress concentration is significantly affected by material property and applied electric charges, and not appreciably influenced by magnetic charges.
Material characterization of a Kelvin chain from dynamic response
Authors: Ram Y.M. , Voyiadjis G.Z. 
Published: November 2004

AbstractThe springs and dampers comprising a Kelvin chain can be determined from dynamic test data. The paper shows how to construct the parameters of the chain by using: (a) the dynamic response data to constant load, and (b) the poles and zeros of a collocated transfer function at the end of the chain. The results may be used in characterizing the material properties of a sample from laboratory experimental data.
CHARACTERISTICS OF PHOSPHORUS LIMITATION IN CHLAMYDOMONAS REINHARDTH (CHLOROPHYCEAE) AND ITS PALMELLOIDS1
Authors: Olsen Ynguar , Knutsen Gjert , Lien Torleiv 
Published: November 2004

ABSTRACT Chlamydomonas reinhardtii Dang, was grown in a chemostat culture under phosphate limitation. The steady state concentration of phosphate was below the detection limit (< 1 μg P/L) in all runs. The cellular content of phosphorus (Qp), polyphosphate (Qpp) and chlorophyll a increased with increasing dilution rate, and the growth rate of the alga was described by Qp as well as Qpp in the Droop model. The ratio Qpp/Qp and the activity of alkaline phosphatase were maximal at high and low growth rates, respectively. Palmelloids of Chlamydomonas were found at high dilution rates (D > 0.12 h−1) and became attached to the wall of the culture vessel. They differed from the vegetative stage in both chemical composition and growth rate. Their contents of phosphorus and chlorophyll a were low, as in the vegetative cells, which grew at a low growth rate, whereas the ration Qpp/Qp and the activity of alkaline phosphatase were comparable with those of fast growing vegetative cells. The growth rate of the palmelloids was 0.03 h−1 whereas maximum growth rate (μm) for the vegetative cells was 0.21 h−1.