bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sezawa and love modes in Co/Cu superlattices
Authors: Błachowicz Tomasz 
Published: August 2006

AbstractIn this paper detailed theoretical study and experimental results concerning acoustic surface and undersurface propagation modes in multilayered Co/Cu superlattices are provided. The theoretical approach was adopted from that of Adler and Farnel. Experimental results were obtained in Brillouin light-scattering measurements. The Sezawa and Love acoustic modes were observed as a result of boundary conditions at the interface between hexagonal and cubic structures.
A boson approach to the structure of A=22 nuclei
Authors: Kwaśniewicz Edward , Hetmaniok Edyta , Brzostowski Jakub , Catara Francesco , Sambataro Michelangelo 
Published: August 2006

AbstractWe discuss a procedure to transfer the description of a fermion system from a subspace of the full shell model space built in terms of collective pairs onto a space of corresponding bosons. We apply the procedure to systems of six nucleons in the 1s0d major shell. We perform exact shell model calculations and compare them with calculations in the collective pair and boson approximations. The effects of the truncation of the boson Hamiltonian and of the consequent violation of the Pauli principle are examined.
Diffusion times and stability exponents for nearly integrable analytic systems
Authors: Lochak Pierre , Marco Jean-Pierre 
Published: August 2006

Abstract
For a positive integer n and R>0, we set
$$B_R^n = \left\{ {x \in \mathbb{R}^n |\left\| x \right\|_\infty< R} \right\}$$
. Given R>1 and n≥4 we construct a sequence of analytic perturbations (H
j) of the completely integrable Hamiltonian
$$h\left( r \right) = \tfrac{1}{2}r_1^2 + ...\tfrac{1}{2}r_{n - 1}^2 + r_n $$
on
$$\mathbb{T}^n \times B_R^n $$
, with unstable orbits for which we can estimate the time of drift in the action space. These functions H
j are analytic on a fixed complex neighborhood V of
$$\mathbb{T}^n \times B_R^n $$
, and setting
$$\varepsilon _j : = \left\| {h - H_j } \right\|_{C^0 (V)} $$
the time of drift of these orbits is smaller than (C(1/ɛ
j)1/2(n-3)) for a fixed constant c>0. Our unstable orbits stay close to a doubly resonant surface, the result is therefore almost optimal since the stability exponent for such orbits is 1/2(n−2). An analogous result for Hamiltonian diffeomorphisms is also proved. Two main ingredients are used in order to deal with the analytic setting: a version of Sternberg's conjugacy theorem in a neighborhood of a normally hyperbolic manifold in a symplectic system, for which we give a complete (and seemingly new) proof; and Easton windowing method that allow us to approximately localize the wandering orbits and estimate their speed of drift.
Analytic Feynman integrals of transforms of variation of cylinder type functions over Wiener paths in abstract Wiener space
Authors: Kim Myung 
Published: August 2006

Abstract
In this paper, we evaluate various analytic Feynman integrals of first variation, conditional first variation, Fourier-Feynman transform and conditional Fourier-Feynman transform of cylinder type functions defined over Wiener paths in abstract Wiener space. We also derive the analytic Feynman integral of the conditional Fourier-Feynman transform for the product of the cylinder type functions which define the functions in a Banach algebra introduced by Yoo, with n linear factors.
Local properties of the solution set of the operator equation in Banach spaces in a neighbourhood of a bifurcation point
Authors: Janczewska Joanna 
Published: August 2006

Abstract
In this work we study the problem of the existence of bifurcation in the solution set of the equation F(x, λ)=0, where F: X×R
k
→Y is a C
2-smooth operator, X and Y are Banach spaces such that X⊂Y. Moreover, there is given a scalar product 〈·,·〉: Y×Y→R
1 that is continuous with respect to the norms in X and Y. We show that under some conditions there is bifurcation at a point (0, λ0)∈X×R
k and we describe the solution set of the studied equation in a small neighbourhood of this point.
On the existence of solutions for nonlinear impulsive periodic viable problems
Authors: Cardinali Tiziana , Servadei Raffaella 
Published: August 2006

Abstract
In this paper we prove the existence of periodic solutions for nonlinear impulsive viable problems monitored by differential inclusions of the type x′(t)∈F(t,x(t))+G(t,x(t)). Our existence theorems extend, in a broad sense, some propositions proved in [10] and improve a result due to Hristova-Bainov in [13].
On almost hyperHermitian structures on Riemannian manifolds and tangent bundles
Authors: Bogdanovich Serge , Ermolitski Alexander 
Published: August 2006

Abstract
Some results concerning almost hyperHermitian structures are considered, using the notions of the canonical connection and the second fundamental tensor field h of a structure on a Riemannian manifold which were introduced by the second author.
With the help of any metric connection
$$\tilde \nabla $$
on an almost Hermitian manifold M an almost hyperHermitian structure can be constructed in the defined way on the tangent bundle TM. A similar construction was considered in [6], [7]. This structure includes two basic anticommutative almost Hermitian structures for which the second fundamental tensor fields h
1 and h
2 are computed. It allows us to consider various classes of almost hyperHermitian structures on TM. In particular, there exists an infinite-dimensional set of almost hyperHermitian structures on TTM where M is any Riemannian manifold.
Quaternionic and para-quaternionic CR structure on (4n+3)-dimensional manifolds
Authors: Alekseevsky Dmitri , Kamishima Yoshinobu 
Published: August 2006

Abstract
We define notion of a quaternionic and para-quaternionic CR structure on a (4n+3)-dimensional manifold M as a triple (ω1,ω2,ω3) of 1-forms such that the corresponding 2-forms satisfy some algebraic relations. We associate with such a structure an Einstein metric on M and establish relations between quaternionic CR structures, contact pseudo-metric 3-structures and pseudo-Sasakian 3-structures. Homogeneous examples of (para)-quaternionic CR manifolds are given and a reduction construction of non homogeneous (para)-quaternionic CR manifolds is described.
Extended finite operator calculus—an example of algebraization of analysis
Authors: Kwaśniewski Andrzej , Borak Ewa 
Published: August 2006

Abstract
“A Calculus of Sequences” started in 1936 by Ward constitutes the general scheme for extensions of classical operator calculus of Rota—Mullin considered by many afterwards and after Ward. Because of the notation we shall call the Ward's calculus of sequences in its afterwards elaborated form—a ψ-calculus.
The ψ-calculus in parts appears to be almost automatic, natural extension of classical operator calculus of Rota—Mullin or equivalently—of umbral calculus of Roman and Rota.
At the same time this calculus is an example of the algebraization of the analysis—here restricted to the algebra of polynomials. Many of the results of ψ-calculus may be extended to Markowsky Q-umbral calculus where Q stands for a generalized difference operator, i.e. the one lowering the degree of any polynomial by one.
This is a review article based on the recent first author contributions [1]. As the survey article it is supplemented by the short indicatory glossaries of notation and terms used by Ward [2], Viskov [7, 8], Markowsky [12], Roman [28–32] on one side and the Rota-oriented notation on the other side [9–11, 1, 3, 4, 35] (see also [33]).
Solitary wave and other solutions for nonlinear heat equations
Authors: Nikitin Anatoly , Barannyk Tetyana 
Published: August 2006

Abstract
A number of explicit solutions for the heat equation with a polynomial non-linearity and for the Fisher equation is presented. An extended class of non-linear heat equations admitting solitary wave solutions is described. The generalization of the Fisher equation is proposed whose solutions propagate with arbitrary ad hoc fixed velocity.
Geometric classes of Goursat flags and the arithmetics of their encoding by small growth vectors
Authors: Mormul Piotr 
Published: August 2006

Abstract
Goursat distributions are subbundles, of codimension at least 2, in the tangent bundles to manifolds having the flag of consecutive Lie squares of ranks not depending on a point and growing—very slowly—always by 1. The length of a flag thus equals the corank of the underlying distribution.
After the works of, among others, Bryant&Hsu (1993), Jean (1996), and Montgomery&Zhitomirskii (2001), the local behaviours of Goursat flags of any fixed length r≥2 are stratified into geometric classes encoded by words of length r over the alphabet {G,S,T} (Generic, Singular, Tangent) starting with two letters G and having letter(s) T only directly after an S, or directly after another T.
It follows from [6] that the Goursat germs sitting in any fixed geometric class have, up to translations by rk D−2, one and the same small growth vector (at the reference point) that can be computed recursively in terms of the G,S,T code. In the present paper we give explicit solutions to the recursive equations of Jean and show how, thanks to a surprisingly neat underlying arithmetics, one can algorithmically read back the relevant geometric class from a given small growth vector. This gives a secondary, Gödel-like super-encoding of the geometric classes of Goursat objects (rather than just a 1-1 correspondence between those classes and small growth vectors).
Antiinflammatory, analgesic and kinase inhibition activities of some acridine derivatives
Authors: Sondhi Sham , Bhattacharjee Gurudas , Jameel Rafid , Shukla Rakesh , Raghubir Ram , Lozach Olivier , Meijer Laurent 
Published: August 2006

Abstract
9-Chloro-2,4-(un)substituted acridines (1) on condensation with sulpha- diazine, sulphathiazole, and sulphaacetamide gave condensation products 3a-h. 3-Aryl-4-phenyl-2-imino-4-thiazolines (4) on condensation with 9-chloro-2,4-(un)substituted acridines (1) gave condensation products 5a–5o. Both 3a–3h and 5a–5o were purified by crystallization or by chromatography. Structures assigned to 3a–3h and 5a–5o are supported by correct spectral data. Antiinflammatory and analgesic activity screening of 3a, 3e, 3f and 5a–5c, 5e, 5g, 5i, 5m, 5n were carried out using carrageenin induced paw oedema and phenyl quinone writhing assay. Some of the compounds exhibited interesting antiinflammatory or analgesic activities.
Aerogel nanoscale magnesium oxides as a destructive sorbent for toxic chemical agents
Authors: Štengl Vaclav , Bakardjieva Snejana , Maříková Monika , Šubrt Jan , Opluštil František , Olšanská Marcela 
Published: August 2006

Abstract
An autoclave hypercritical drying procedure has been used to prepare precursors of MgO from Mg(OCH3)2. This material was prepared with a specific surface area of 1200 m2
g
1. The dehydrated materials consisted of much smaller crystallites than conventionally prepared MgO and were free of OCH3 groups. The precursors and samples of magnesium oxide were taken for experimental evaluation of their reactivity with mustard. The largest percentage of the conversion mustard into non-toxic products after the elapse of the reaction was 77%.
Efficiency assessment of wastewater treatment plant based on SPMD sampling
Authors: Kočí Vladimír , Ocelka Tomáš , Mlejnek Martin , Grabic Roman 
Published: August 2006

Abstract
The efficiency of treatment processes forboth municipal and industrial wastewater (treatment plant-Ostrava, Czech Republic) focused on persistent organic pollutants (POPs) was assessed. Semipermeable membrane devices (SPMDs) as a sampling system were applied. Exposed SPMDs were analyzed both for chemical contaminants of POPs and toxicity response. The chemical analyses of PAHs were made by HPLC-FLD, PCDD/Fs and PCBs were analysed by GC/MS/MS on GCQ or PolarisQ (Thermoquest). Ecotoxicity data on chlorococcal alga Desmodesmus subspicatus (Scenedesmus subspicatus) and luminescent bacteria Vibrio fischeri are presented here. All toxicity data as effective volume Vtox are expressed. The results show good treatment ability of the treatment plant and proved used system as an appropriate tool for efficiency assessment of treatment and/or decontamination processes.
Amidoalkylation of heteroaromatic compounds with adducts of acyl chlorides and 3,4-dihydroisoquinoline and isoquinoline
Authors: Venkov Atanas , Statkova-Abeghe Stela , Donova Atanaska 
Published: August 2006

Abstract
The N-acyliminium intermediates of 3,4-dihydroisoquinoline and salts of isoquinoline with acyl chlorides were successfully used as amidoalkylating reagents toward synthesis of heterocyclic aromatics as indole, pyrrole, thiophene and pyrazine.
Hydrogen yield from water radiolysis in the presence of zeolites
Authors: Cecal Alexandru , Colisnic Dan , Popa Karin , Paraschivescu Andrei , Bilba Nicolae , Cozma Danut 
Published: August 2006

Abstract
This paper reports a study of the decomposition of water by gamma radiolysis in the presence of zeolites ZSM-5, SAPO-5, and MOR. The irradiation is performed using 60Co as a source with 1.12×1015 Bq activity at a 8.3 kGy/h dose rate. The stable products of radiolysis as well as the other chemical species are measured by mass spectrometry. The calculated radiation yield (GH
2) generally decreases in the order: H-ZSM-5>Na-ZSM-5>H-SAPO-5>MOR under the given experimental conditions; the yield is higher in the presence of these catalysts than in their absence.
Crystal structure, infrared and raman spectra of tripotassium trisaccha-rinate dihydrate, K3(C7H4NO3S)3·2H2O
Authors: Jovanovski Gligor , Kaitner Branko , Grupce Orhideja , Naumov Pance 
Published: August 2006

Abstract
The crystal structure of tripotassium trisaccharinate dihydrate, K3(C7H4NO3S)3·2H2O, is triclic, space group
$$P \bar 1, Z = 2$$
. It consists of three crystallographically independent potassium and saccharinato ions as well as two structurally different water molecules. Potassium coordination polyhedra are irregular, with K1 and K3 six-coordinated and the third one K2 seven-coordinated. The K−O distances range from 2.652(9) to 3.100(2) Å(mean: 2.790 Å) whereas the K−N distance is 3.025(3) Å. The water molecules W2 is disordered over three positions with occupancies of approximately 0.6, 0.2 and 0.2. The hydrogen atom (H1W1) of the ordered water molecule (O1W) is hydrogen bonded to the sulfonyl oxygen atom (O11) (R(O...O)=2.976(3) Å), whereas the other hydrogen atom (H2W1) is bifurcated to the carbonyl oxygen atom (O13) (R(O...O)=2.851(3) Å) and the disordered water molecules (O23W) (R(O...O)=3.067(12) Å). The carbonyl oxygens (O13, O23 and O33) and one of the disordered water molecules (O22W) are involved in C−H...O hydrogen bonds (R(C−H...O)=3.027(4)–3.304(9) Å). Structural characteristics of the studied compound are compared with the analogous trisodium trisaccharinate dihydrate and dipotassium sodium trisaccharinate monohydrate. Infrared and Raman spectra of the title compound have been analyzed in relation to the structure, and compared with the spectra of trisodium trisaccharinate dihydrate.
Determination of aristolochic acid by capillary zone electrophoresis
Authors: Kvasnička František , Ševčík Rudolf , Voldřich Michal , Krátká Jana 
Published: August 2006

AbstractA simple and rapid capillary zone electrophoresis (CZE) method for the determination of aristolochic acid (AA) in dietary supplements and selected herbs is described. A clear separation of AA from other sample constituents was achieved within 5 minutes without any sample clean up. A mixture of 20 mM-morpholinethanesulphonic acid+10 mM-BisTrisPropane+0.2% hydroxyethylcelullose in 10% methanol serves as a background electrolyte. The linearity, accuracy, intra-assay and detection limit of the developed method are 200–6000 ng/mL, 95–103%, 3.5%, and 50 ng/ml, respectively. Ease of use, sufficient sensitivity and low running cost are the most important attributes of the CZE method. The proposed CZE method was compared with HPLC.
Removal of 60Co2+ and 137Cs+ ions from low radioactive solutions using Azolla caroliniana willd. water fern
Authors: Popa Karin , Cecal Alexandru , Humelnicu Doina , Caraus Ioan , Draghici Camelia 
Published: August 2006

AbstractThis study concerns the removal of the 137Cs+ and 60Co2+ β+γ-radioactive ions in Azolla caroliniana Willd. water fern. The living fern and two different types of biosorbent prepared from Azolla caroliniana were tested to remove the above-mentioned radioactive ions from dilute solutions, in the absence and in the presence of the ionic competition. Effective 137Cs+ and 60Co2+ ions removal from low radioactive wastewaters was demonstrated. The time dependent K d(t) values were calculated from the absorption data. These results indicate that removal process achieved equilibrium in about 120 min and that it involves two steps: rapid and slow absorption; the active process (metabolic bioaccumulation on the living fern) was responsible for above one half of the total removal process. A thin layer radiochromatography study leads to the conclusion that the biochemical components in which 137Cs+ and 60Co2+ place themselves are of a polysaccharide and lipoid fractions.
Theoretical study of structure, vibrational and electronic spectra of isomers of methyl-3-methoxy-2-propenoate
Authors: Virdi Ajit , Gupta V. , Sharma Archna 
Published: August 2006

AbstractA systematic quantum mechanical study of the possible conformations, their relative stabilities, vibrational and electronic spectra and thermodynamic parameters of methyl-3-methoxy-2-propenoate has been reported for the electronic ground (S0) and first excited (S1) states using time-dependent and time-independent Density Functional Theory (DFT) and RHF methods in extended basis sets. Detailed studies have been restricted to the E-isomer, which is found to be substantially more stable than the Z-isomer. Four possible conformers c′Cc, c′Tc, t′Cc, t′Tc, of which the first two are most stable, have been identified in the S0 and S1 states. Electronic excitation to S1 state is accompanied with a reversal in the relative stability of the c′Cc and c′Tc conformers and a substantial reduction in the rotational barrier between them, as compared with the S0 state. Optimized geometries of these conformers in the S0 and S1 states are being reported. Based on suitably scaled RHF/6-31G** and DFT/6-311G** calculations, assignments have been provided to the fundamental vibrational bands of both these conformers in terms of frequency, form and intensity of vibrations and potential energy distribution across the symmetry coordinates in the S0 state. A complete interpretation of the electronic spectra of the conformers has been provided.
Flow-injection analysis with a small cylindrical wire type electrode
Authors: Denchev Zhivko , Nikolov Nikola 
Published: August 2006

AbstractAn amperometric detector with a small thin mercury film electrode is described. The device demonstrates advantageous operational characteristics such as small dispersion (D<2) and “memory effect” (me<0.6%), extensive maximum sample frequency (msf −200 samples/h), and high sensitivity. It has been proven useful in flow-injection analysis at a constant potential under hydrodynamic conditions.
Voltammetric determination of the trace amounts of bromate in drinking water after pre-concentration on hydrous γ-Al2O3
Authors: Kościelna Honorata , Ren Maria 
Published: August 2006

AbstractA differential pulse voltammetric (DPV) method for the determination of bromate in drinking water, after pre-concentration on γ-Al2O3, is proposed. The reduction peak of bromate has been observed at the potential Ep-−1.6 V in an ammonia buffer as a supporting electrolyte. The method has been successfully applied to determine a bromate concentration of 2.5 μg·l−1 in drinking water (RSD=6.1%, n=7). A sample pre-treatment with a column filled with mixed cation-exchange resin in Ag, Ba and H forms was needed before pre-concentration of bromate on alumina.
QSPR modeling aqueous solubility of polychlorinated biphenyls by optimization of correlation weights of local and global graph invariants
Authors: Castro Eduardo , Toropov Andrey , Nesterova Alexandra , Nabiev Ozad 
Published: August 2006

AbstractAqueous solubilities of polychlorinated biphenyls have been correlated with topological molecular descriptors which are functions of local and global invariants of labeled hydrogen filled graphs. Morgan extended connectivity and nearest neighboring codes have been used as local graph invariants. The number of chlorine atoms in biphenyls has been employed as a global graph invariant. Present results show that taking into account correlation weights of global invariants gives quite reasonable improvement of statistical characteristics for the prediction of aqueous solubilities of polychlorinated biphenyls.
The role of quantum interference in determining transport properties of molecular bridges
Authors: Walczak Kamil 
Published: August 2006

AbstractAn analytical approach to the electron transport phenomena in molecular devices is presented. The analyzed devices are composed of various molecular bridges attached to two semi-infinite electrodes. Molecular system is described within the tight-binding model, while the coupling to the electrodes is analyzed through the use of Newns-Anderson chemisorption theory. The current-voltage (I-V) characteristics are calculated through the integration of transmission function in the standard Landauer formulation. The essential question of quantum interference effect of electron waves is diseussed in three aspects: (i) the geometry of a molecular bridge, (ii) the presence of an external magnetic field and (iii) the location of chemical substituent.
Characterization and sorption properties of Aspergillus niger waste biomass
Authors: Ŝpanêlová M. , Machoviĉ V. , Březina M. 
Published: August 2006

AbstractThe structure and the biosorption properties of fungal biomass of Aspergillus niger originated from citric acid fermentation industry was investigated. This waste biomass, produced in high quantity in carefully controlled industrial processes, has certain favourable characteristics that may be improved for its usefulness. In environmental chemistry, it is known for the removal of heavy metals cations. In this work, different alkaline treatments (1M NaOH/20°C/24 h and 10M NaOH/107°C/6 h) were used to evaluate the dependence of sorption properties of biomass on the cell wall composition. The biosorption was studied by the batch method, with the biomass concentration of 1 g/l, at pH 6. The adsorption of lead was more effective than that of cadmium. The biosorption capacity was evaluated using the biosorption isotherm derived from the equilibrium data. At pH 6, the maximmum lead biosorption capacity estimated with the Langmuir model was 93 mg/g dry biomass.
Functionalization of polyolefins by reactive processing
Authors: Zelenetskii A. , Volkov V. , Artem’eva N. , Sizova M. , Nikol’skaya V. , Egorova N. 
Published: August 2006

AbstractFrom the study of the modification of PE and PP with maleic anhydride, maleic acid and an acid salt of maleic acid (sodium maleate) in a liquid or solid state, it was shown that the main controlling factor in the solid state modification of polyolefins is the joint plastic deformation of the system components. The changes of molecular characteristics were investigated by gel permeation chromatography. It was shown, that the molecular weight of modified PP samples increases at times by linking with intermolecular associates in the solutions. The formation of associates plays essential role in the behaviour of solutions of modified PP. The morphology of modified PP samples was investigated by scanning electron microscopy. It was shown, that intermolecular association strongly influences on the processes of formation and growth of nucleus and the structure of generated polymeric materials.