bluuebunny/crossref_metadata_2025 huggingface dataset:
Solid phase microextraction sampling and gas chromatography/mass spectrometry for field detection of the chemical warfare agent O‐ethyl S‐(2‐diisopropylaminoethyl) methylphosphonothiolate (VX)
Authors: Hook Gary L. , Kimm Gregory , Betsinger Geoffrey , Savage Paul B. , Swift Austin , Logan Tom , Smith Philip A.
Published: August 2003

A rapid detection method for the chemical warfare nerve agent VX was developed using SPME and gas chromatography/mass spectrometry (GC/MS). Five commercially available SPME fiber coatings were evaluated to determine the optimal fiber coating and conditions for extraction. The use of silanized vials was found to be necessary to limit interaction of the basic tertiary amine component of VX with the acidic silanols present in standard glass vials. The polydimethylsiloxane (PDMS) fiber was ultimately selected for completion of this work with extractions being performed at 50°C. Clothing material was spiked in the laboratory with 1 μL of neat VX, placed in a sealed vial, and taken into the field for SPME sampling, using optimized conditions studied. GC/MS analysis was also completed in the field using van‐mounted instrumentation. With sampling and analysis completed in less than 20.0 minutes, detection of VX contamination was relatively rapid, especially considering the quality of the resulting data. The use of SPME also provides increased safety for the field analysis of VX since it does not require the handling of solvents for sample preparation and samples are not handled directly by the analyst.
Novel Polymerization of Fluorinated 2‐Vinylcyclopropane in Aqueous Solution via Cyclodextrin Complexes
Authors: Choi Soo Whan , Kretschmann Oliver , Ritter Helmut , Ragnoli Marina , Galli Giancarlo
Published: August 2003

We report on the first examples of the free radical polymerization of a fluorinated 2‐vinylcyclopropane 1 and its copolymerization with an alkyl 2‐vinylcyclopropane 2 in aqueous solution via their host‐guest complexation with a random methylated β‐cyclodextrin (RAMEB) using a water‐soluble initiator (VA50). Upon polymerization, the dethreaded cyclodextrin remained in water solution, whereas the water‐insoluble polymer precipitated out and was isolated. The polymers prepared exhibited mesophase behavior over a wide range of temperature. Both Tg and Ti of the copolymers increased linearly with the amount of fluorinated co‐units.

Complexation of fluorinated vinylcyclopropane 1 with RAMEB and polymerization in water solution.

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Complexation of fluorinated vinylcyclopropane 1 with RAMEB and polymerization in water solution.
Morphology and Crystallization Kinetics of Melt Miscible Polyolefin Blends
Authors: Müller Alejandro J. , Arnal Maria Luisa , Spinelli Ana Liz , Cañizales Edgar , Puig Cristian C. , Wang Howard , Han Charles C.
Published: August 2003

Blends of copolymers of ethylene/hexene (9 CH3/1 000 C) and ethylene/butene (77 CH3/1 000 C) synthesized with metallocene catalysts were prepared by co‐precipitation from solution. A phase diagram for this blend had been obtained in a preceding work, where the blends were found to be miscible in the melt with a characteristic upper critical solution temperature (UCST). In this work, the successive self‐nucleation and annealing (SSA) thermal fractionation method revealed that both pure copolymers, even though they had been prepared by metallocene catalysis, displayed a very broad distribution of short chain branching. The thermal behavior of the pure copolymers and their blends revealed that co‐crystallization effects were present within each phase and that molecular fractionation during crystallization can prevail when the materials are slow cooled from the melt. A crystallization kinetics study was performed by differential scanning calorimetry (DSC) and it revealed a strong competition between crystallization and phase segregation. Upon cooling from a one phase melt, phase segregation precedes crystallization if the crystallization temperature (Tc) is high. On the other hand when low crystallization temperatures are employed, the amount of phase segregation that can be achieved before crystallization is limited. Transmission electron microscopy (TEM) allowed the observation of the lamellar morphology and their aggregation state. In specially prepared samples, the relative lamellar frequency of isothermally crystallized material was employed to ascertain whether the blend under consideration was within the one or the two phase region of the blends phase diagram.

Crystallization half‐time for isothermally crystallized PEB/PEH blends quenched to the crystallization temperature from 170 °C.

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Crystallization half‐time for isothermally crystallized PEB/PEH blends quenched to the crystallization temperature from 170 °C.
Crystallization and Melting Behaviors of PPC‐BS/PVA Blends
Authors: Zhang Zhihao , Mo Zhishen , Zhang Hongfang , Wang Xianhong , Zhao Xiaojiang
Published: August 2003

The isothermal crystallization and melting behaviors of poly(propylene carbonate) end‐capped with benzenesulfonyl/poly(vinyl alcohol) (PPC‐BS/PVA) blends over rich PVA composition range were first investigated by differential scanning calorimetry (DSC). PPC‐BS/PVA interaction parameter, χ12, calculated from equilibrium melting temperature depression was −0.44, revealing miscibility of PPC‐BS with PVA in the melt and favorable interactions. The temperature dependence of crystallization rate constant at initial crystallization stage was analyzed using the modified Lauritzen‐Hoffman expression. The chain width, a0, the thickness of a monomolecular layer, b0, the fold and lateral surface free energies, σe and σ, and the work of chain folding, q, for neat PVA were first reckoned to be 4.50 Å, 4.78 Å, 76.0 erg · cm−2, 8.81 erg · cm−2, and 4.70 kcal · mol−1, respectively. The values of σe and q for PVA in PPC‐BS/PVA blends exhibited a maximum in the neighborhood of 10/90 PPC‐BS/PVA, respectively.

Kinetic analysis of the temperature dependence of crystallization rate constant at initial crystallization stage for neat PVA and PPC‐BS/PVA blends.

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Kinetic analysis of the temperature dependence of crystallization rate constant at initial crystallization stage for neat PVA and PPC‐BS/PVA blends.
Thermal‐Induced Crystal/Conformation Transformations in Syndiotactic Polystyrene Films Treated with Different Solvents
Authors: Sun Ya Sen , Woo E. M. , Wu Ming Chien
Published: August 2003

Solution‐crystallized or solvent‐induced crystal forms and transitions of these crystals upon post‐annealing in solvent‐treated syndiotactic polystyrene (sPS) (films cast from o‐dichlorobenzene or immersed in 1,2‐dichloroethane, respectively) were investigated via wide‐angle X‐ray diffraction (WAXD), differential scanning calorimetry (DSC), and Fourier‐transform infrared (FTIR) spectroscopy. IR spectra in the frequency range of 720–820 cm−1, which is attributed to the CH out‐of‐plane bending of the phenyl ring for neat syndiotactic polystyrene (sPS) and their crystal/solvent complexes (sPS/o‐dichlorobenzene or sPS/1,2‐dichloroethane), were examined for the freshly as‐cast samples in comparison with those having been subjected to post‐annealing by heating to high temperatures. Three bands centered at approximately 779, 769, and 750 cm−1 were observed, the intensity and wavenumber being sensitive to the helical structural changes as a function of the annealing temperature. The band at 769 cm−1, being associated with the intramolecular interactions of the helical chains of the γ‐crystal, was used to confirm the formation of such a phase. The bands at 779 cm−1 and 769 cm−1 disappeared and the sharper band at 750 cm−1 remained upon further annealing above the γ → α′ transition temperature. Thus, by examining the temperature dependency as revealed in the IR spectra, the thermal‐induced phase transition from the δ‐ to an ordered γ‐ and then to an α′‐phase was successfully proven for the sPS/o‐dichlorobenzene complex. Similarly, the other sPS/1,2‐dichloroethane complex underwent transition (from a δ‐ to a disordered γ‐ and then to an α′‐phase) upon the same thermal treatments, except that the intermediate phase is a disordered γ‐phase.

FTIR spectra in the frequency ranging from 720 to 820 cm−1 for the δ‐type sPS/o‐dichlorobenzene complex subjected to increase of the temperature by 5 °C steps in the range of 60–245 °C.

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FTIR spectra in the frequency ranging from 720 to 820 cm−1 for the δ‐type sPS/o‐dichlorobenzene complex subjected to increase of the temperature by 5 °C steps in the range of 60–245 °C.
Positron Annihilation in Norbornene‐Ethylene Copolymers
Authors: Djourelov Nikolaj , Misheva Marijka , Zamfirova Galina , Benavente Rosario , Pérez Ernesto , Pereña José M.
Published: August 2003

Norbornene‐ethylene amorphous copolymers with high content in norbornene are obtained with metallocene catalysts and present a high glass transition temperature. The size and concentration of the free‐volume holes of these copolymers, which affect to their gas barrier properties, has been studied by positron annihilation lifetime spectroscopy. The results of positron annihilation studies have shown that the microstructure of all samples is similar and they can be related to the dynamic mechanical parameters (temperatures and activation energies of the relaxations) as well as to the stress‐strain characteristics and microhardness of the copolymers. Moreover, it has been shown that in the case of the norbornene‐ethylene copolymers investigated the influence of the molecular rigidity on the glass transition temperature prevails over that of the pore dimensions.

Apparent activation energies and reciprocal values of tan δ for the γ relaxation as functions of volumes of the holes determined at Tg −50 °C.

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Apparent activation energies and reciprocal values of tan δ for the γ relaxation as functions of volumes of the holes determined at Tg −50 °C.
Novel Labile Protected Amine Terpolymers for the Preparation of Patterned Functionalized Surfaces: Synthesis and Characterization
Authors: Braun Felix , Eng Lukas , Trogisch Sven , Voit Brigitte
Published: August 2003

Photolabile terpolymers have been designed and used to prepare thin organic films covalently attached to glass and silicon substrates. For this, terpolymers containing photolabile protected amino functions introduced by N‐(N‐nitroveratryloxycarbonylaminopropyl)methacrylamide as well as (trimethoxysilyl)propylmethacrylate and MMA as comonomers have been synthesized via free radical polymerization. The nitro group containing protecting group leads to a retardation of the free radical polymerization. But complete removal of non‐reacted monomer from the reaction product without gelation of the anchoring groups was achieved. Thin films from these terpolymers were structured imagewise by UV laser light irradiation in order to create defined functional areas at the template surface ready for further modification and attachment of nanoobjects. The selective deprotection was verified by UV‐imaging and selective modification reaction using fluorescence labeling.

Area selective UV imaging of a AMINE‐P7 film; presentation of the changes in optical density after UV laser irradiation.

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Area selective UV imaging of a AMINE‐P7 film; presentation of the changes in optical density after UV laser irradiation.
Effect of LiClO4 and LiCl Additives on the Kinetics of Anionic Polymerization of Methyl Methacrylate in Toluene‐Tetrahydrofuran Mixed Solvent
Authors: Dhara Mahua G. , Baskaran Durairaj , Sivaram Swaminathan
Published: August 2003

The kinetics of anionic polymerization of MMA has been studied at −78 °C in toluene‐THF (9:1 v/v) using 1,1′‐diphenylhexyl lithium as initiator in the presence of lithium perchlorate and lithium chloride as Lewis acid additives. The control of the polymerization is lost in the absence of additives as evident from the non‐linear first‐order time‐conversion plot and polymers with broad multimodal molecular weight distribution. The presence of LiClO4 and LiCl in 10:1 and 5:1 ratio, respectively, over the initiator brings about sufficient control, yielding polymers of narrow unimodal distribution throughout the polymerization. The reaction in the presence of the additives follows first‐order kinetics free of termination and transfer. Moreover, the order with respect to the active centers is found to be almost unity, which signifies a probable disaggregation of ion‐pairs to a single complexed propagating species.

GPC elugrams at different conversions for MMA polymerization in the presence of LiClO4.

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GPC elugrams at different conversions for MMA polymerization in the presence of LiClO4.
Aqueous Micelles from Supramolecular Graft Copolymers
Authors: Gohy Jean‐François , Hofmeier Harald , Alexeev Alexander , Schubert Ulrich S.
Published: August 2003

Aqueous micelles have been prepared from amphiphilic supramolecular graft copolymers, in which poly(ethylene glycol) (PEG) side chains were linked to a poly(methyl methacrylate) (PMMA) backbone via ruthenium(II)‐terpyridine complexes. Three different graft copolymers were investigated, in which the average number of PEG branches (constant length) and the length of the PMMA backbone were varied. The successful formation of micelles was proven by dynamic light scattering (DLS), atomic force microscopy (AFM), and transmission electron microscopy (TEM). A good agreement was found between TEM and AFM observations, which show polydisperse spherical micelles. The hydrodynamic diameter measured by DLS was much larger, suggesting the formation of aggregates. No substantial difference in the micellar characteristic features was found between the three investigated samples.

Schematic representation of the graft copolymer synthesis.

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Schematic representation of the graft copolymer synthesis.
Molecular and Microdomain Orientation in Semicrystalline Block Copolymer Thin Films by Directional Crystallization of the Solvent and Epitaxy
Authors: Park Cheolmin , Rosa Claudio De , Lotz Bernard , Fetters Lewis J. , Thomas Edwin L.
Published: August 2003

The directional crystallization of crystallizable organic solvents and the subsequent epitaxial crystallization of crystalline blocks onto the surface of crystalline substrates in semicrystalline block copolymers, control both molecular chain orientation of the crystalline block and the microdomain structure of the block copolymer. Thin film of semicrystalline polystyrene‐block‐poly(ethylene‐alt‐propylene)‐block‐polyethylene (PS/PEP/PE) terpolymer and polystyrene‐block‐polyethylene (PS/PE) diblock copolymer, which both contain crystallizable polyethylene (PE) blocks, have been patterned using benzoic acid (BA) and anthracene (AN) as crystallizable solvents. The directional crystallization induces orientation of the microdomains and epitaxy, due to the crystallographic matching of unit cells between the crystalline PE blocks and the crystalline organic substrates, resulting in the development of highly aligned crystalline PE blocks. The orientation of the PE crystals onto the substrate is evidenced by selected area electron diffraction and bright field transmission electron microscope images. In the case of the PS/PEP/PE terpolymer, the process induces the PS cylinders to align parallel to the b axis of the BA crystals. Long crystalline PE lamellae are oriented edge‐on on the BA surface, with the b axis of PE parallel to the b axis of BA, and parallel to the PS cylinders. In the case of the PS/PE diblock copolymer, the PE cylinders are oriented perpendicular to substrate, packed on a hexagonal lattice. Each cylinder contains precisely one crystalline PE lamella oriented edge‐on on the substrate. When BA is used, the PE lamellae inside cylinders are oriented with the b axis parallel to the b axis of BA crystals. When AN is used, due to the different epitaxial relationship between PE block and AN crystals, the PE lamellae are oriented along two equivalent directions, with the c axis parallel to the [110] and $\left[ {1\bar 10} \right]$ direction of AN crystals.

Schematic model of the final microstructure generated by combination of the directional crystallization and epitaxy.

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Schematic model of the final microstructure generated by combination of the directional crystallization and epitaxy.
Structure and Thermoelastic Behavior of Synthetic Rubber/Organoclay Nanocomposites
Authors: Privalko Valery P. , Ponomarenko Sergiy M. , Privalko Eleonora G. , Schön Frank , Gronski Wolfram , Staneva Rosina , Stühn Bernd
Published: August 2003

Nanocomposites of synthetic styrene‐co‐butadiene rubber and three types of organoclay fillers were prepared by melt‐compounding and characterized by small‐angle X‐ray scattering (SAXS), differential calorimetry and stretching calorimetry. The in‐rubber structure of the organoclay particles is characterized by different degrees of intercalation with interlayer distances ranging from 3.1–4.8 nm. In contrast to the pristine rubber, all nanocomposites exhibited irreversibility of both mechanical work and heat effects in stretching/contraction cycles at fairly low elongations. Moreover, at the same filler loading both the mechanical reinforcement effect and the magnitude of specific heat effects proved strongly dependent on the degree of intercalation. In the range of low elongations, significantly earlier onsets of the heat inversion phenomenon (compared to theoretically expected), as well as the overshoots of exothermal heat effects in contraction above the endothermal heat effects in stretching for nanocomposites, suggested the contribution of structural rearrangements at the rubber/filler interface by the mechanism of chain slippage operative in both stretching and contraction regimes. In the range of high elongations, the thermoelastic behavior of nanocomposites could be accounted for quantitatively by the model, which assumed explicitly the contributions of local strain amplification for the rubber matrix and of successive decay of nanoparticle clusters with increasing strain, generating the exothermal effects of external friction between nanoparticles.

Dependency on relative elongation of specific mechanical work (squares) and specific heat effects (circles) for the pristine rubber.

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Dependency on relative elongation of specific mechanical work (squares) and specific heat effects (circles) for the pristine rubber.
Preparation and Characterisation of Pd Nanoclusters in Hyperbranched Aramid Templates to be used in Homogeneous Catalysis
Authors: Tabuani Daniela , Monticelli Orietta , Komber Hartmut , Russo Saverio
Published: August 2003

In the present paper the potential use of hyperbranched (HB) aramids as metallic solution stabilisers and carriers for homogeneous catalysis is outlined. Aramids, synthesised either from A2 + B3 reagents [namely, p‐phenylenediamine (PPD) and trimesic acid (TMA)] or from an AB2 monomer [i.e., 5‐(4‐aminobenzamido)isophtalic acid, named ABZAIA], have been used to stabilise palladium nanoclusters dispersed in two solvent media, namely N,N′‐dimethylformamide (DMF) and dimethyl sulfoxide (DMSO). The influence of the nature of the polymeric support as well as of the solvent medium on both cluster dimensions and stability of the solutions has been investigated. Indeed, the interactions between the polymeric support and the metallic precursor (PdCl2), as revealed by 1H NMR spectroscopy, involve only the amino groups of the HB aramids. Metal nanocluster dimensions and stability are strongly dependent on the polymer used as a stabilizer. Transmission electron microscopy (TEM) analysis has shown that the presence of HB polymer in the solution reduces cluster dimensions and allows the obtaining of stable systems. The low concentration of NH2 end groups in the poly(AB2) system leads to the formation of Pd particles of rather low dimensions with a high tendency to aggregate. All prepared solutions are stable under inert atmosphere for at least a month, with an improved stabilisation when using the poly(A2 + B3) system for more than five months.

A TEM micrograph of poly(ABZAIA)/Pd from a DMSO solution.

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A TEM micrograph of poly(ABZAIA)/Pd from a DMSO solution.
Polymers of Carbonic Acid, 33
Authors: Kricheldorf Hans R. , Böhme Sigrid , Schwarz Gert , Schultz Claus‐Ludolf
Published: August 2003

The interfacial, hydrolytic polycondensation of bisphenol‐A‐bischloroformate (BABC) was performed at 5 or 35 °C initial temperature with the following amines as catalysts: isoquinoline, pyridine, 4‐methylpyridine, 4‐tert‐butylpyridine, 4‐(dimethylamino)pyridine, 2,4,6‐trimethylpyridine and ethyldiisopropylamine. The reaction products were characterized by viscosity and SEC measurements and by MALDI‐TOF mass spectrometry. In all products (with the exception of 2,4,6‐trimethylpyridine‐catalyzed samples) cyclic oligo‐ and polycarbonates (identified up to masses around 15 000 Da) were found. Their content was particularly high when 4‐(dimethylamino)pyridine was used or when a neutral salt was added to pyridine catalyzed polycondensations. A higher temperature reduced both molecular weight and content of cycles regardless, if pyridine or ethyldiisopropylamine was used as the catalyst. Furthermore, equimolar amounts of bisphenol‐A and BABC were polycondensed in anhydrous dichloromethane using pyridine or ethyldiisopropylamine as the catalyst and HCl acceptors. In both cases low molar mass polycarbonates mainly consisting of even‐membered cycles were obtained. The reaction mechanisms are discussed. All results prove that both highly nucleophilic and highly basic tert‐amines can efficiently catalyze chain growth and cyclization, provided that the reaction conditions are accordingly optimized. Both chain growth and cyclization mainly occur in the organic phase.

MALDI‐TOF mass spectrum of the polycarbonate prepared by pyridine promoted polycondensation of bisphenol‐A and BABC in dry CH2Cl2.

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MALDI‐TOF mass spectrum of the polycarbonate prepared by pyridine promoted polycondensation of bisphenol‐A and BABC in dry CH2Cl2.
Quasi–concave envelope of a function and convexity of level sets of solutions to elliptic equations
Authors: Colesanti Andrea , Salani Paolo
Published: August 2003

Given a C2 function u, we consider its quasi–convex envelope u* and we investigate the relationship between D2u and D2u* (the latter intended in viscosity sense); we obtain two inequalities between the tangential Laplacian of u and u* and the normal second derivative of u and u* (the words tangential and normal are referred to a level set of the involved functions). Then we apply the result to prove convexity of level sets of solutions of elliptic equations in convex rings. Our results can be applied to a class of elliptic operator which can be naturally decomposed in a tangential and a normal part, such as Laplacian, p–Laplacian or the Mean Curvature operator. (© 2003 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A generalized Hankel transform on Lν,r–spaces
Authors: Glaeske Hans–Jürgen , Kilbas Anatoly A.
Published: August 2003

An integral transform with a kernel generalizing the Bessel function of the first kind is investigated in weighted Lp–spaces. Mapping properties, such as the boundedness, the representation and the range of the transform, are given and an inversion formula is proved. (© 2003 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Measures of non–compactness of classical embeddings of Sobolev spaces
Authors: Hencl Stanislav
Published: August 2003

Let Ω be an open subset of ℝn and let p ∈ [1, n). We prove that the measure of non–compactness of the Sobolev embedding Wk,p0(Ω) → Lp*(Ω) is equal to its norm. This means that the entropy numbers of this embedding are constant and equal to the norm. The same is true, when λn(Ω) is small enough, for the embedding of W1,n0(Ω) into the Orlicz space with Young function exp(tn/(n−1) − 1. The position is different for the embedding of W1,p0(J) in C0,1−1/p($ \bar J $), J equals; (0, 1), when p ∈ (1,∞): in this case the measure of non–compactness is less than the norm. (© 2003 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Analytic continuation and identities involving heat, Poisson, wave and Bessel kernels
Authors: Jorgenson Jay , Lang Serge
Published: August 2003

In this article we use classical formulas involving the K–Bessel function in two variables to express the Poisson kernel on a Riemannian manifold in terms of the heat kernel. We then use the small time asymptotics of the heat kernel on certain Riemannian manifolds to obtain a meromorphic continuation of the associated Poisson kernel to all values of complex time with identifiable singularities. This result reproves in a different setting by different means a well–known theorem due to Duistermaat and Guillemin [DG 75]. Also, we develop analytic expressions for the heat kernel beyond asymptotic expansions. (© 2003 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Nonlinear absolutely summing mappings
Authors: Matos Mário C.
Published: August 2003

A mapping f, defined on an open subset A of a Banach space E, with values in another Banach space F, such that (f(a + xj) −f(a))∞j=1 is absolutely summable in F, whenever (xj)∞j=1 is unconditionally summable (respectively, absolutely summable) in E, is called absolutely summing (respectively, regularly summing) at the point a ∈ A. It is proved that f is regularly summing at a if, and only if, there areM > 0 and δ > 0, such that ‖f(a + x) − f(a)‖ ≤ M ‖x‖, for all ‖x‖ ≤ δ. This result has as a consequence a characterization of absolutely summing mappings by means of inequalities. This result is analogous to the well know characterization of the linear absolutely summing mappings. Several results and examples show that the existence of non–linear absolutely summing mappings is not a rare phenomena. A Dvoretzky–Rogers Theorem for n–homogeneous polynomials is proved. (© 2003 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Hyers–Ulam stability of linear differential operator with constant coefficients
Authors: Miura Takeshi , Miyajima Shizuo , Takahasi Sin–Ei
Published: August 2003

Let P(z) be a polynomial of degree n with complex coefficients and consider the n–th order linear differential operator P(D). We show that the equation P(D)f = 0 has the Hyers–Ulam stability, if and only if the equation P(z) = 0 has no pure imaginary solution. (© 2003 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Exposed points and extremal problems in H1 on a bidisc
Authors: Nakazi Takahiko
Published: August 2003

An essential bounded function ϕ gives a continuous linear functional on the Hardy space H1 on the bitorus. In this paper, we consider extremal problems on H1 when ϕ is a rational function, ϕ is a product of one variable functions or ϕ = |f|/f for some outer function f in H1 such that f(z, w) has a good property with respect to w for a.e. z. (© 2003 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Guest editorial: Evolutionary psychology and consumption
Authors: Hantula Donald A.
Published: August 2003

Consumer behavior is discussed as a biobehavioral phenomenon and considered in light of evolutionary theory. Current consumer choices are viewed as shaped in the environment of evolutionary adaptedness (EEA), and the expression of these evolved behavioral repertoires in modern consumer settings such as malls, grocery stores, and on‐line shopping are analyzed in terms of evolutionary psychology. A variety of empirical studies confirm that consumption conforms to predictions made from sexual strategies, reciprocal altruism, foraging, and matching theories. Further explorations of consumer behavior and marketing practices from an evolutionary psychology perspective are a promising area for future research. © 2003 Wiley Periodicals, Inc.
An evolutionary psychology perspective on gift giving among young adults
Authors: Saad Gad , Gill Tripat
Published: August 2003

With evolutionary psychology used as the theoretical framework, two aspects of gift giving among young adults are investigated: (a) sex differences in motives for giving gifts to a romantic partner, and (b) the allocation of gift expenditures among various relations, including romantic partners, close friends, close kin, and distant kin members. As per the evolved sex differences in mating strategies, it is proposed and found that men report tactical motives for giving gifts to their romantic partners more frequently than women. Also, there are no sex differences in situational motives for giving gifts. In addition, women are aware that men use tactical motives more often; whereas men think that these motives are employed equally by both sexes. With regard to gift expenditures it is found that, for kin members, the amount spent on gifts increases with the genetic relatedness (rvalue) of the particular kin. When all relations (kin and nonkin members) are included, the allocation of gift expenditures were the highest to romantic partners, followed by those to close kin members and then to close friends. The latter finding is explained via the importance attached to the evolved psychological mechanisms linked to each of the above relations, namely, reproductive fitness (for partners), nonreproductive fitness (for close kin members), and reciprocal altruism (for close friends). © 2003 Wiley Periodicals, Inc.
Optimal foraging online: Increasing sensitivity to delay
Authors: DiClemente Diane F. , Hantula Donald A.
Published: August 2003

This experiment is a replication and extension of the Rajala and Hantula (2000) study of sensitivity to feedback delay while shopping in a simulated Internet mall. The experiment consisted of three conditions: One group had an ascending clock placed on the computer screen to cue the passage of time, another group had a descending clock placed on the computer screen, and as a control and replication condition, another group had no clock on the computer screen. Participants were more sensitive to the delays in the various stores in the cybermall when an ascending clock was present on the screen. A hyperbolic discount function fit best described the number of entries into each store, amount of time spent in each store, and relative number of purchases in each store. A customer‐satisfaction survey showed decreasing positive attitudes toward the stores as a function of delay. These results have implications both in terms of foraging theory applied to human behavior, as well as for the practice of online marketing. © 2003 Wiley Periodicals, Inc.
The behavioral ecology of brand choice: How and what do consumers maximize?
Authors: Foxall Gordon R. , James Victoria K.
Published: August 2003

Matching theory predicts choices on concurrent variable ratio schedules on which consumers' brand selection occurs will show maximization via exclusive choice of the richest schedule. However, aggregate studies of consumer choice indicate two modes of consumer brand purchase within a product category: either exclusive purchase of one brand or multibrand purchasing. This article uses brand‐selection data from individual consumers to determine whether, at this level of analysis, (a) consumers' purchasing patterns show matching, (b) consumers maximize returns, and, if so, (c) what they maximize. Consumer behavior for fast‐moving goods exhibits matching, but in the form of multibrand purchasing rather than exclusive choice. Moreover, for substitutes, brand selection is price sensitive, suggesting both melioration and maximization; for nonsubstitutes, choice is not price sensitive but still appears consistent with maximization of price‐ and nonprice‐related sources of value. © 2003 Wiley Periodicals, Inc.
Intuitive evolutionary perspectives in marketing practices1
Authors: Colarelli Stephen M. , Dettmann Joseph R.
Published: August 2003

Firms spend considerable sums of money on marketing, and they continue to do so because marketing works. However, marketing can only work if marketers have a reasonably accurate view of human nature. It is argued that many consumer products and advertisements reflect an accurate view of human nature, a view that is compatible with the tenets of evolutionary psychology. Implicit theories of human nature that are out of synch with reality sell few products. An overview of an evolutionary perspective on marketing is provided here, and connections between marketing practices and evolved adaptations, including kin selection, prestige seeking, preferences for salt, sweets, and fat, and savanna‐like landscapes are examined. Adaptations that differ by sex and how they are mirrored in marketing are also examined. Finally, some marketing practices that reflect evolutionary principles of variation are discussed. © 2003 Wiley Periodicals, Inc.
One‐Component Bimolecular Photoinitiating Systems, 2
Authors: Aydin Meral , Arsu Nergis , Yagci Yusuf
Published: August 2003

The compounds 2‐thioxanthone‐thioacetic acid and 2‐(carboxymethoxy)thioxanthone, bimolecular photoinitiators for free radical polymerization, are synthesized and characterized. Their capability to act as initiators for the polymerization of methyl methacrylate was examined. The postulated mechanism is based on the intermolecular electron‐transfer reaction of the excited photoinitiator with the sulfur or oxygen atom of the ground state of the respective photoinitiator followed by decarboxylation. The resulting alkyl radicals initiate the polymerization.

Structures of the photoinitiators.

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Structures of the photoinitiators.
Green Nanocomposites from Renewable Resources: Biodegradable Plant Oil‐Silica Hybrid Coatings
Authors: Tsujimoto Takashi , Uyama Hiroshi , Kobayashi Shiro
Published: August 2003

Green nanocomposite coatings based on renewable plant oils have been developed. An acid‐catalyzed curing of epoxidized plant oils with 3‐glycidoxypropyltrimethoxysilane produced transparent nanocomposites. The hardness and mechanical strength improved by incorporating the silica network into the organic polymer matrix, and good flexibility was observed in the nanocomposite. The nanocomposites showed high biodegradability.

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Frozen‐In Magnetic Order in Uniaxial Magnetic Gels: Preparation and Physical Properties
Authors: Collin Dominique , Auernhammer Günter K. , Gavat Odile , Martinoty Philippe , Brand Helmut R.
Published: August 2003

We describe the preparation and characterization of uniaxial magnetic gels. Fibril formation of the embedded magnetic particles generates easily detectable magnetic and optical anisotropies. A finite magnetization is frozen‐in and leads to a ferromagnetic‐like response in small homogeneous external magnetic fields. We present, for the first time, frequency dependent measurements of the shear modulus G′. Despite their optical and magnetic anisotropy, the gels are mechanically isotropic.

The time‐dependent G′ for a ferrogel in the parallel orientation in a homogeneous field of 200 mT.

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The time‐dependent G′ for a ferrogel in the parallel orientation in a homogeneous field of 200 mT.
Poly(vinyl alcohol)‐Encapsulated Hydrophilic Carbon Black Nanoparticles Free from Aggregation
Authors: Li Han‐Ying , Chen Hong‐Zheng , Sun Jing‐Zhi , Cao Jian , Yang Zheng‐Long , Wang Mang
Published: August 2003

Carbon black (CB) nanoparticles were encapsulated by poly(vinyl alcohol) (PVA) by a simple method of coacervation. Transmission electron microscopy (TEM) images clearly demonstrated that the successful encapsulation of PVA happened at the surfaces of CB nanoparticles. The particle‐size distribution measurements indicated that the diameters of the obtained PVA‐encapsulated CB (CB@PVA) nanoparticles were distributed within the nanoscale dimension. This strategy avoids the complicated polymerization process involved in the counterpart of polymer‐coating approaches.

A TEM image of PVA‐encapsulated carbon black.

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A TEM image of PVA‐encapsulated carbon black.
Bis(Phenoxy‐Imine) Zr Complexes/Et3Al/Heteropoly Compound Catalyst Systems for Ethylene Polymerization
Authors: Bando Hideki , Nakayama Yasushi , Sonobe Yoshiho , Fujita Terunori
Published: August 2003

Bis(phenoxy‐imine) Zr complexes upon activation with Et3Al/(Ph3C)mHn[PMo12O40] · 8 H2O (average: m/n = 2:1) were demonstrated to be highly active catalysts for the polymerization of ethylene. One of the complexes formed narrow‐molecular‐weight distributed polyethylene ($\overline M _{\rm w} /\overline M _{\rm n}$ 1.45) with a very high activity (5640 kg‐PE · mol‐cat−1 · h−1), representing the first example of a MAO‐ and borate‐free, highly active, single‐site catalyst system based on a Group 4 transition metal complex and a heteropoly compound.

Catalysis of ethylene with bis(phenoxy‐imine) Zr complexes activated with Et3Al/(Ph3C)mHn[PMo12O40] · 8 H2O.

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Catalysis of ethylene with bis(phenoxy‐imine) Zr complexes activated with Et3Al/(Ph3C)mHn[PMo12O40] · 8 H2O.
AFM Study of the Self‐Assembly Behavior of Hexa‐Armed Star Polymers with a Discotic Triphenylene Core
Authors: Yu Xiang , Fu Jun , Han Yanchun , Pan Caiyuan
Published: August 2003

The six‐armed polystyrenes and poly(methyl methacrylate)s with a triphenylene core showed different self‐assembling patterns, isolated cylinders for polySt on mica and highly ordered cylindrical pores for polyMMA on a silicon wafer. With a decrease of polymer concentration in tetrahydrofuran (THF), the size and height of cylinders decreased for polySt, but for polyMMA, the size and depth of the cylindrical pores increased. Slow evaporation of the solvent and a low molecular weight favored the formation of regular patterns.

AFM images of self‐assembling patterns of polySt 1a on mica (A) and of polyMMA 2a on silicon wafer (B).

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AFM images of self‐assembling patterns of polySt 1a on mica (A) and of polyMMA 2a on silicon wafer (B).
Thermal Degradation Processes in Poly(acyl sulfides) Investigated by Pyrolysis–Gas Chromatography/Mass Spectrometry
Authors: Sundarrajan Subramanian , Srinivasan Kalathur S. V.
Published: August 2003

A series of poly(acyl sulfides) were synthesized by polycondensation of acid dichlorides with sodium sulfide using tetrabutylammoniumhydrogen sulfate as a phase transfer catalyst. The thermal stability of these polymers was determined by thermogravimetric analysis. A unique phenomenon of exothermic degradation behavior was observed by differential thermal analyses, which is attributed to the energetics of the acylsulfide linkage during the thermal degradation. The mechanism of formation of degradation products was investigated by the pyrolysis–gas chromatography/mass spectrometry (Py‐GC/MS) technique.

The acylsulfide linkage containing polymers synthesized exhibit unique degradation behavior.

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The acylsulfide linkage containing polymers synthesized exhibit unique degradation behavior.
Credit cards scoring with quadratic utility functions
Authors: Bugera Vladimir , Konno Hiroshi , Uryasev Stanislav
Published: August 2003

The paper considers a general approach for classifying objects using mathematical programming algorithms. The approach is based on optimizing a utility function, which is quadratic in indicator parameters and is linear in control parameters (which need to be identified). Qualitative characteristics of the utility function, such as monotonicity in some variables, are included using additional constraints. The methodology was tested with a ‘credit cards scoring’ problem. Credit scoring is a way of separating specific subgroups in a population of objects (such as applications for credit), which have significantly different credit risk characteristics. A new feature of our approach is incorporating expert judgments in the model. For instance, the following preference was included with an additional constraint: ‘give more preference to customers with higher incomes.’ Numerical experiments showed that including constraints based on expert judgments improves the performance of the algorithm. Copyright © 2003 John Wiley & Sons, Ltd.
CCAS: an intelligent decision support system for credit card assessment
Authors: Matsatsinis Nikolaos F.
Published: August 2003

During the last two decades credit cards have became one of the main ways for accomplishing financial transactions. The number of credit card owners have increased rapidly. Unfortunately, at the same time the cases where the owners cannot fulfil their obligations to the banks have also been increased. This fact forced credit institutions and banks to search for methodologies that will allow them to accurately evaluate the credibility of each credit card applicant. Multi‐criteria decision aid methods as well as machine learning algorithms can be used to accomplish this task. The present paper proposes a new intelligent decision support system for credit card evaluation, based on a machine‐learning algorithm, namely the Composite Rule Induction System and the Rough Sets. The major advantage of the algorithm and the system is the incorporation of qualitative variables, which have an essential role in credit card evaluation. The system is applied on a real case study concerning credit card evaluation by a leading Greek commercial bank and the obtained results are compared to the results of multi‐criteria decision aid methods as well as other machine learning algorithms. Copyright © 2003 John Wiley & Sons, Ltd.
The use of goal programming, regression analysis and data envelopment analysis for estimating efficient marginal costs of hospital services
Authors: Giokas D.
Published: August 2003

This paper presents a new composite methodology for estimating efficient marginal costs of outputs. The methodology is based on multi‐criteria methods involving Data Envelopment Analysis (DEA), Goal Programming (GP) and Regression Analysis (RA) techniques. Firstly, DEA is used to find an empirical frontier onto which each observed dependent variable (cost) is projected. Then GP or RA is applied to the projected data set to yield the parameter estimates of a cost function. That is, firstly, the amounts of technical inefficiency are removed and then the cost function is estimated. The parameters of the cost function provide the efficient marginal costs of outputs. The filtering of the data can be made by means of DEA as it yields target values with frontier rather than average behaviour. The results clearly indicate the superiority of the combination of DEA and GP over the combination of DEA and RA. The methodology was applied to estimate the efficient marginal costs of hospital services (inpatient days, outpatient visits, ancillary services) of public general hospitals in Greece. Concluding, the analysis proves that the estimation of efficient marginal costs of outputs is in author's view particularly useful for hospitals, and can serve as a theoretical basis for determining the prices of different hospital services. Copyright © 2003 John Wiley & Sons, Ltd.
Multi‐criteria evaluation of loan applications in shipping
Authors: Dimitras Augustinos I. , Petropoulos Theodore , Constantinidou Isabella
Published: August 2003

The development of the shipping industry has been traditionally based on bank loans. An important step in the credit granting process is the application for the loan and the consequent evaluation of this application by the bank. Numerous bankers, consultants, as well as academics have been addressing this matter, presenting requirements to be satisfied and attributing values indicating the soundness and the financial strength of the applicant (company and/or individual), in relation to the characteristics of the loan application in the loan approval process. The work, however, done on the construction of standardized models able to combine all these criteria and provide relative weighting to assist the decision‐making process of the Bank's Credit Committee is limited.

The ability of the multi‐criteria methods to utilize both qualitative and quantitative criteria in the evaluation process renders them a comprehensive tool for the formulation and expression of the shipping credit granting decision. This paper proposes a multi‐criteria methodology for the evaluation of credit applications and for the selection of those applications that better match the policy of the bank as well as the industry knowledge and the shipfinance experience of the decision maker. The study illustrates the application of the method using a suitable set of ship loan applications and the model developed is evaluated according to its usefulness in a decision process. Copyright © 2003 John Wiley & Sons, Ltd.
Multi‐criteria decision aid in financial decision making: methodologies and literature review
Authors: Zopounidis Constantin , Doumpos Michael
Published: August 2003

Over the past decades the complexity of financial decisions has increased rapidly, thus highlighting the importance of developing and implementing sophisticated and efficient quantitative analysis techniques for supporting and aiding financial decision making. Multi‐criteria decision aid (MCDA), an advanced field of operations research, provides financial decision makers (DMs) and analysts a wide range of methodologies, which are well suited to the complexity of financial decision problems. The aim of this paper is to provide an in‐depth presentation of the contributions of MCDA in the field of finance, focusing on the methods used and their real‐world applications. Copyright © 2003 John Wiley & Sons, Ltd.
Trade credit and customer relationships
Authors: Summers Barbara , Wilson Nicholas
Published: August 2003

Trade credit is an important economic phenomenon, and a variety of theories have been put forward to explain the decisions firms make on credit extension. The ways in which credit can be used as a strategic tool to support corporate objectives has not, however, been fully discussed. The results presented here provide some support for the extant theory on trade credit extension and for recent empirical papers in this area (e.g. Ng et al., 1999; Petersen and Rajan, 1994). However, our results suggest that trade credit granting has a set of subtle and complex motivations over and above those predicted by standard theory. In particular trade credit extension can be used as a many‐faceted marketing/relationship management tool and/or as a means of signalling information to the market or to specific buyers about the firm, its products and its future prospects/commitment. Much of credit extension can be seen as customer focused; for example, encouraging frequent purchasers which offer the potential for relationship development or accommodating customers' demand for credit to help finance their production period. The requirements/bargaining power of large customers can influence a firm to extend more credit. Firms will vary terms in anticipation of capturing new business, to attract specific customers and in order to achieve specific marketing aims. Copyright © 2003 John Wiley & Sons, Ltd.