bluuebunny/crossref_metadata_2025 huggingface dataset:
Distinguishing between the Meanings of Music: When Background Music Affects Product Perceptions
Authors: Zhu Rui (Juliet) , Meyers-Levy Joan
Published: August 2005

Music theory distinguishes between two types of meanings that music can impart: (1) embodied meaning, which is purely hedonic, context independent, and based on the degree of stimulation the musical sound affords, and (2) referential meaning, which is context dependent and reflects networks of semantic-laden, external world concepts. Two studies investigate which (if either) of these background music meanings influence perceptions of an advertised product and when. Findings suggest that people who engage in nonintensive processing are insensitive to either type of meaning. However, more intensive processors base their perceptions on the music's referential meaning when ad message processing requires few resources, but they use the music's embodied meaning when such processing is relatively resource demanding.
The Impact of the Prechoice Process on Product Returns
Authors: Bechwati Nada Nasr , Siegal Wendy Schneier
Published: August 2005

This article introduces a framework to help researchers understand the mechanisms underlying product returns. The framework draws on research in consumer choice, consumer memory, and attitude stability to predict how the process that consumers go through at a predecisional stage affects their postpurchase behavior. The likelihood of product returns is considered contingent on the amount and nature of cognitive responses generated during the choice process. In Study 1, the authors focus on the impact of the nature of cognitive responses and show that the generation of responses of a different nature while choosing directly affects the likelihood of choice reversal. The comparative versus non-comparative nature of thoughts generated influences their diagnosticity and, accordingly, their impact on product returns when consumers are exposed to disconfirming information. In Study 2, the authors draw on the inoculation theory to manipulate the number of prechoice thoughts. They find that when faced with disconfirming information favoring a new brand, inoculated consumers who are presented with choice alternatives sequentially are less likely to return a brand than consumers who are exposed solely to positive information about the chosen brand at a prepurchase stage.
Terahertz-Time-Domain-Spektroskopie mit einem leistungsoptimierten elektrooptischen Detektionsverfahren (Low-Power Terahertz Time-Domain Spectroscopy with Optimized Electro-optical Detection)
Authors: Gorenflo Stefan , Hinkov Iliyana , Lambrecht Armin , Fischer Bernd , Hoffmann Matthias , Helm Hanspeter , Jepsen Peter Uhd
Published: August 2005

Ein Terahertz-Time-Domain-Spektroskopie- (THz-TDS-) System mit elektrooptischem Detektor auf der Basis von ZnTe wird vorgestellt. Als Laserquelle dient ein Ti:Sa-Laser, der Laserpulse mit einer Dauer von ca. 10 fs bei einer zentralen Wellenlänge von 800 nm liefert. Durch Optimierung des Detektionsverfahrens wurde mit nur 25 mW Laserleistung ein Signal-Rausch-Verhältnis (SNR) von größer als 103 erzielt. Die aufgenommenen Spektren bekannter Substanzen weisen materialspezifische Absorptionslinien auf und erlauben deren eindeutige Erkennung.
Langzeit-Aerosolüberwachung mit einem kalibrierfreien, kompensierten Streulichtfotometer (Long Term Monitoring by Means of a Calibration-Free, Compensated Light Scattering Photometer)
Authors: Laile Edgar , Zahoransky Richard A. , Poss Gerhard , Riedel Wolfgang , Ulmer Ulrich , Grisar Roland
Published: August 2005

Zur Messung geringer Massenkonzentrationen und der Partikelgrößenverteilung unter hohen Druck- und Temperaturbedingungen, wie sie z.B. bei Überwachung des Gasstromes in Druckwirbelschichtfeuerungen oder in Druckkohlestaubfeuerungen vorkommen, wird ein kompensiertes Streulichtfotometer vorgeschlagen. Streulicht- und Transmissionswerte des Partikelkollektivs werden erfasst und miteinander verknüpft. Als Vorteil dieses Mess- und Auswerteprinzips ergibt sich im Gegensatz zu konventionellen Fotometern eine weitgehende Unempfindlichkeit gegenüber Fenster-Verschmutzung und Alterung von Komponenten. Das neue Konzept ist bis etwa 900 ºC einsatzfähig.
ACTH 1-24 inhibits proliferation of adrenocortical tumors in vivo
Authors: Zwermann Oliver , Schulte Dominik M , Reincke Martin , Beuschlein Felix
Published: August 2005

Objectives: Although several lines of evidence suggest that the overall effects of the ACTH receptor, melanocortin 2 receptor (MC2-R), mediated signal transduction on adrenocortical growth and tumorigenesis are anti-proliferative, activation of MC2-R induces mitogens like jun, fos, and myc and activates the MAPK pathway.In vivo, potential effects of endogenous ACTH on adrenal tumori-genesis can not be separated from effects of other POMC derived peptides.

Methods: Murine adrenocortical tumor cells that lack MC2-R expression (Y6pcDNA) and Y6 cells stablely transfected with MC2-R (Y6MC2-R) were generated. Presence of functional MC2-R was demonstrated by RT-PCR and Western blot using an antibody for phosphorylated CREB. As a syngenic tumor model, LaHeF1/J mice simultaneously received 107Y6MC2-Rand Y6pcDNAsubcutaneously, giving rise to MC2-R positive and negative tumors within the same animal. Animals were treated for 3 weeks in groups of 12 according to the following schedule: group A, control animals receiving saline injection; group B, animals receiving 5.7 ng/injection of a slow release formula of ACTH 1-24 administered i.p. three times a week (aiming at a low physiologic dose); and group C, animals receiving 57 ng/injection of ACTH 1-24 (high physiological dose).

Results: Twenty days of ACTH 1-24 treatment did not significantly affect corticosterone levels, endogenous ACTH levels or adrenal and thymus weight compared with saline injection. However, ACTH 1-24 treatment of group B and C mice significantly reduced tumor weight in MC2-R positive tumors in a dose dependent manner (P= 0.03), while no significant difference in tumor mass was observed in MC2-R negative tumors. PCNA and TUNEL staining, together with morphological characterization, demonstrated that thesein vivoeffects were due to reduced proliferation, while apoptosis and cellular hypertrophy within the tumor remained unchanged.

Conclusion: MC2-R expression is associated with a less aggressive adrenal tumor phenotype and anti-proliferative effects can be amplified through stimulation with physiological doses of ACTH.
Regulation of CRH-induced secretion of ACTH and corticosterone by SOM230 in rats
Authors: Silva A P , Schoeffter P , Weckbecker G , Bruns C , Schmid H A
Published: August 2005

Objective: Adrenocorticotropic hormone (ACTH)-dependent Cushing’s syndrome is biochemically characterized by increased plasma concentrations of ACTH inducing hypersecretion of cortisol. Somatostatin is known to inhibit ACTH secretion, and in vitro data have shown the inhibition of ACTH secretion by agonists activating sst2 and sst5 receptors. The present study aimed to determine the inhibitory effect of the multireceptor ligand SOM230, compared with the sst2-preferring agonist octreotide, on corticotropin-releasing hormone (CRH)-stimulated secretion of ACTH and corticosterone in rats.

Methods: Secretion of ACTH and corticosterone was induced by i.v. application of CRH (0.5 μg/kg) in rats pretreated 1 h before by i.v. application of SOM230 (1, 3, or 10 μg/kg), octreotide (10 μg/kg) or NaCl 0.9%.

Results: SOM230 (3 and 10 μg/kg) inhibited CRH-induced ACTH release by 45±3% and 51±2%, respectively, and corticosterone release by 43±5% and 27±16%, respectively. 10 μg/kg of octreotide tended to be less potent at inhibiting ACTH release (34±6% inhibition) and did not alter the secretion of corticosterone.

Conclusion: SOM230 has a stronger inhibitory effect on ACTH and corticosterone secretion than octreotide in rats. This difference can be explained by its higher affinity to sst1, sst3 and especially sst5 receptors compared with octreotide.
A Method for Correcting the Relative Weight (Wr) Index for Seasonal Patterns in Relative Condition (Kn) with Length as Applied to Walleye in Wisconsin
Authors: Hansen Michael J. , Nate Nancy A.
Published: August 2005

We determined whether the relative weight (Wr) model for walleye Sander vitreus was representative of populations in Wisconsin and if relative weight varied with length seasonally. We then developed standard condition (Kn) models that correct for seasonal variation in body condition. We compiled data from 54,657 walleyes sampled during 640 surveys of 202 lakes in 30 Wisconsin counties. Weight–length relationships and mean relative weight varied more widely for Wisconsin populations than for North American populations overall. Weight–length relationships and mean relative weight varied significantly among seasons, with the highest slope (lowest intercept) and mean relative weight in spring, lowest slope (highest intercept) and mean relative weight in early summer, and intermediate slopes (and intercepts) and mean relative weights in late summer and autumn. Mean relative weight increased with length in spring, decreased with length in early summer, and did not change with length in late summer, autumn, or over all seasons combined. For samples collected in spring or early summer, we found that relative weight did not accurately index body condition or estimate trends in body condition with length. We propose a new index, adjusted relative weight (the product of Wr and a seasonal Kn model, Wr · Kn) that adjusts relative weight for life-history-based seasonal trends in body condition with length.
Simple plasticity-based prediction of the undrained settlement of shallow circular foundations on clay
Authors: Osman A. S. , Bolton M. D.
Published: August 2005

A kinematic plastic solution has been developed for the penetration of a circular footing into an incompressible soil bed. In this solution, the pattern of deformation around the footing is idealised by a simple plastic deformation mechanism. Strain-hardening behaviour and nonlinear stress–strain characteristics are incorporated. This application is different from conventional applications of plasticity theory as it can approximately predict both stresses and displacements under working conditions. This approach therefore provides a unified solution for design problems in which both serviceability and safety requirements are based directly on the stress–strain behaviour of the soil. The design strength that should limit the deformations can be selected from the actual stress–strain data recorded from a carefully specified location, and not derived using empirical safety factors. The validity of this design approach is examined against nonlinear finite element analyses and field measurements of foundations on clay under short-term loading.
Partial factors calibration based on reliability analyses for square footings on granular soils
Authors: Honjo Y. , Amatya S.
Published: August 2005

Partial safety factors for square footings for highway bridges resting on granular soils have been determined based on reliability analyses. Some example cases are chosen based on a database which includes detailed information of 1869 actually constructed highway bridge pier shallow foundations in one fiscal year in Japan. The designs obtained, using calculations based on the bearing capacity equations by Meyerhof and by Brinch Hansen as modified by Vesic, are compared. The uncertainties involved in the bearing capacity equations are investigated through a comprehensive literature review. The seismic forces determined from the peaks over threshold analysis and fitted to a general Pareto distribution have been considered. The first-order reliability method (FORM) and Monte Carlo simulations (MCS) are employed to determine and compare the 100-year failure probabilities of the shallow foundations designed. It is found that FORM gives a considerably lower failure probability than MCS. Finally, partial factors obtained using calculations based on the two bearing capacity equations are carefully reviewed. It is found that the design value method used to determine partial factors by FORM does not appropriately give either the partial factors or the failure probability for the case of shallow foundation design where the performance function is highly non-linear and some of the basic variables follow distributions that are far from the normal distribution.
Serviceability of a 79-storey tall building under typhoon conditions
Authors: Li Q. S. , Xiao Y. Q. , Wong C. K. , Hau S. K. , Jeary A. P.
Published: August 2005

This paper presents some results obtained from field measurements of wind effects on a super-tall building, the Di-Wang Tower, located in Shenzhen, China. The building has 79 storeys, and is approximately 324 m high. Simultaneous and continuous data on wind speed, wind direction and acceleration responses were recorded at the top of the building. The field data presented in this paper were measured during the passage of a typhoon. The characteristics of the typhoon-generated wind and the structural responses of the building are investigated. The serviceability of this super-tall building under typhoon conditions is discussed on the basis of the field measurements.
Digitalis-like Compounds: the Discovery of the O-aminoalkyloxime Group as a Very Powerful Substitute for the Unsaturated γ-Butyrolactone Moiety
Authors: Gobbini Mauro , Cerri Alberto
Published: August 2005

Digitalis compounds are used in the treatment of congestive heart failure as positive inotropic agents; their action is mainly due to the inhibition of the Na+,K+-ATPase. A well-known drawback is their arrhythmogenic potential together with a low therapeutic index. Digitalis compounds are characterized by a cis/trans/cis steroidal skeleton with an α, β-unsaturated lactone ( γ-butyrolactone) in the 17 β-position, a 14 β- hydroxy group and a 3 β-hydroxy group, the latter usually linked to one or more sugar rings. The first three moieties are considered essential for inotropic activity, while the glycosides are responsible for the pharmacokinetics of the compounds. This review briefly reports on some of the replacements for the unsaturated γ-butyrolactone moiety and then summarizes the work at Prassis that led to the discovery of the O-aminoalkyloxime group as a very powerful substitute. We also report on the development of new steroidal compounds which act as digitalis-like inhibitors of the Na+,K+-ATPase, without any of the chemical features that are peculiar to naturally occurring digitalis glycosides.
Carnosine and Carnosine-Related Antioxidants: A Review
Authors: Guiotto Andrea , Calderan Andrea , Ruzza Paolo , Borin Gianfranco
Published: August 2005

First isolated and characterized in 1900 by Gulewitsch, carnosine ( β-alanyl-L-hystidine) is a dipeptide commonly present in mammalian tissue, and in particular in skeletal muscle cells; it is responsible for a variety of activities related to the detoxification of the body from free radical species and the by-products of membrane lipids peroxidation, but recent studies have shown that this small molecule also has membraneprotecting activity, proton buffering capacity, formation of complexes with transition metals, and regulation of macrophage function. It has been proposed that carnosine could act as a natural scavenger of dangerous reactive aldehydes from the degradative oxidative pathway of endogenous molecules such as sugars, polyunsaturated fatty acids (PUFAs) and proteins. In particular, it has been recently demonstrated that carnosine is a potent and selective scavenger of α,β-unsaturated aldehydes, typical by-products of membrane lipids peroxidation and considered second messengers of the oxidative stress, and inhibits aldehyde-induced protein-protein and DNA-protein cross-linking in neurodegenerative disorders such as Alzheimers disease, in cardiovascular ischemic damage, in inflammatory diseases. The research for new and more potent scavengers for HNE and other α,β-unsaturated aldehydes has produced a consistent variety of carnosine analogs, and the present review will resume, through the scientific literature and the international patents, the most recent developments in this field.
Quinoxaline 1,4-Dioxide: A Versatile Scaffold Endowed With Manifold Activities
Authors: Carta A. , Corona P. , Loriga M.
Published: August 2005

Since 1940s, Quinoxaline 1,4-dioxides (QdNOs) are known as potent antibacterial agents, and subtherapeutic levels have been used to promote growth and improve efficiency of feed conversion in animal feed. They have also shown a selective cytotoxicity against hypoxic cells present in solid tumours. Furthermore, recent studies have put in evidence that QdNOs are endowed with antitubercular, antiprotozoal and anticandida activities. On the other hand, several authors have reported about photoallergic and mutagenic effects of some derivatives. QdNOs may also cause the development of antibiotic-resistant bacteria and influence the horizontal transfer of virulence genes between bacteria. In this review article we report the biological properties, the mode of action and Structure Activity Relationship (SAR) studies of the QdNO derivatives. Furthermore, some cytogenetic and genotoxic effects, classical and more recent method of synthesis, the quinoxaline 1,4-dioxides, and some of their most important reactions, were also reported.
Antedrugs: An Approach to Safer Drugs
Authors: Khan M. O.F , Park Kwan K. , Lee Henry J.
Published: August 2005

The antedrug concept was introduced by Lee and Soliman in 1982 in designing potent, yet safer locally active anti-inflammatory steroids. Antedrug is defined as an active synthetic derivative that is designed to undergo biotransformation to the readily excretable inactive form upon entry in the systemic circulation. Thus, are minimizing systemic side effects and are increasing the therapeutic indices. Steroid-21-oate esters have been developed as the first of this kind, which quickly hydrolyzed to the corresponding inactive steroid acids thereby exerting minimal systemic side effects. Later, other steroidal and nonsteroidal antedrugs have also been developed. The cost, complexity and length in development of a new therapeutic drug, in addition to the adverse drug reactions, the potential risk factors causing the withdrawal of the drugs from the market, have made the approach of antedrug design unique and attractive to the scientists involved in drug design. Considering these factors, the concept which strictly designed to eliminate the deleterious adverse systemic effects, is becoming an affordable approach in drug development arena. This review is not intended to be comprehensive; instead the focus will be on the recent advances in steroidal as well as nonsteroidal antedrugs, which appear to offer new leverage to the development of safer and more efficacious therapeutic agents.
The Vikings bare their filed teeth
Authors: Arcini Caroline
Published: August 2005

Finds of deliberate dental modification have for the first time been found in archaeological human skeletal material from Europe. The type of modification is a horizontally filed furrow on the frontal upper part of the tooth crown. The furrows are single or, more usually, multiple, and are found on the front teeth in the maxilla. The affected individuals are 24 men from the Viking Age (ca. 800–1050 AD), found in present day Sweden and Denmark. The marks are so well‐made that it is most likely they were filed by a person of great skill. The reason for, and importance of, the furrows are obscure. The affected individuals may have belonged to a certain occupational group (such as tradesmen), or the furrows could have been pure decoration. Am J Phys Anthropol., 2005. © 2005 Wiley‐Liss, Inc.
Dietary Inferences from Dental Occlusal Microwear at Mission San Luis de Apalachee
Authors: Organ Jason M. , Teaford Mark F. , Larsen Clark Spencer
Published: August 2005

San Luis de Apalachee, one of a chain of Roman Catholic missions established in Spanish Florida (modern states of Georgia and Florida) in the sixteenth and seventeenth centuries, was the principal center of missionization of native populations in the Florida panhandle. Paleoethnobotanical remains yield evidence of production of various kinds of crops at the site, typical of nearly all mission period sites in the area. Stable isotope (carbon and nitrogen) analysis and dental caries evidence suggest that maize was not as important in the diet at San Luis as in other contemporary settings in the region. Ethnohistorical research indicates a heavier reliance on meat consumption compared to other mission settings. This study examines dental microwear of occlusal surfaces of maxillary molars from San Luis and five other Native American mission period sites in Spanish Florida. Epoxy casts of molar crushing facets were photographed under 500× magnification, using a scanning electron microscope. Photomicrographs were digitized using Microware 4.02 (Ungar [2002a]) and statistically evaluated using one‐way ANOVA and post hoc Tukey's multiple comparisons tests. These analyses reveal that the frequency of pitting on the San Luis molars is significantly greater than for other mission period sites. Consistent with bioarchaeological, historical, and archaeological documentation, these findings suggest that diets were different in the San Luis natives in comparison with the other native populations in Spanish Florida. Various dietary factors likely came into play, resulting in these differences, and may have included significantly greater meat consumption at San Luis. Am J Phys Anthropol, 2005 © 2005 Wiley‐Liss, Inc.
Study on esterification of acrylic phenolic resin by maleic anhydride and photocrosslinking properties of the alkali‐soluble product
Authors: Xie Hong‐Quan , Zhan Xue‐Gui , Xie Dong
Published: August 2005

An alkali‐soluble, photocrosslinkable polymer was synthesized by esterification of OH groups of acrylic phenolic resin with maleic anhydride. The OH groups were formed by the ring‐opening reaction of epoxy groups of epoxy phenolic resin with acrylic acid. The esterification conditions were studied. The results showed that it is better to use tetramethyl ammonium bromide as catalyst than N,N‐dimethylbenzylamine. The conversion of maleic anhydride in acetone can reach about 80% at 56°C for 4 h. The purified product was characterized by IR, DSC, and TGA. The product containing acrylate and maleic acid monoester groups, above a certain content, can be dissolved in 1% Na2CO3 solution. The photocrosslinkable properties of the product were investigated through selection of photoinitiator, accelarator, crosslinkable diluent monomer, etc. The acrylate and maleic acid monoester group‐containing phenolic resin exhibited very good photocrosslinking behavior, since it contains double bonds from both acrylate groups and maleic acid monoester groups. The activity of photoinitiator decreases in the order: isopropylthioanthraquinone > benzoin ethyl ether (BE) > anthraquinone (AQ) > benzophenone > Michel ketone (MK) > 2,2‐diethoxyacetophenone. The combination of some photoinitiators showed synergistic effects. The order of increasing activity for the accelerator is as follows: MK > ethyl p‐(dimethylamino)benzoate > N,N‐dimethylaniline > triethanolamine. The optimum diluent monomer is trimethylolpropane trimethacrylate. The gel content of the mixture of the resin and trimethylolpropane trimethacrylate could reach 85% using the combined photoinitiators of BE and AQ under UV exposure for 120 s. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1607–1614, 2005
Preparation of monodispersed hollow polymer particles by seeded emulsion polymerization under low emulsifier conditions
Authors: Yuan Cai‐Deng , Miao Ai‐Hua , Cao Jian‐Wei , Xu Yong‐Shen , Cao Tong‐Yu
Published: August 2005

In a low emulsifier system, the MMA‐BA‐MAA copolymer emulsions were prepared as seed latices and the seeded emulsion polymerization of MMA‐MAA‐DVB was consequently carried out to prepare carboxylated core particles. The hydrophobic shell was then synthesized onto the core using styrene, acrylonitrile, and divinylbenzene as comonomers. The hollow latex particles were obtained by alkalization treatment of the core‐shell latex particles. The effects of the feeding rate of monomer mixture, contents of emulsifier SDBS and crosslinking agent DVB, and ratio of the monomers during the core stage and shell stage on the morphology and volume expansion of the latex particles were investigated. The results show that the monodispersed hollow latex particles with large size can be obtained when the feeding rate is 0.1 g/min, SDBS content is 0.15 and 0.2 wt % during the core stage and shell stage, respectively, DVB contents are 1% during the preparation of shell copolymers, and the monomer ratio of the core particle to shell layer is 1 : 8. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1505–1510, 2005
Melt processable conducting poly(aniline‐co‐o‐anisidine)/linear low‐density polyethylene composites with ethylene‐acrylic acid copolymer as compatibilizer
Authors: Wang Gengchao , Shen Zhongyuan , Li Xingwei , Li Chunzhong
Published: August 2005

Conducting composites of aniline/o‐anisidine copolymer doped by dodecylbenzenesulfonic acid (P(An‐co‐oAs)‐DBSA), linear low‐density polyethylene (LLDPE), and ethylene–acrylic acid copolymer (EAA) as compatibilizer were prepared by melt processing. The effects of composition on electrical conductivity, resistivity‐temperature characteristic, and mechanical properties were also investigated. The electrical conductivity of ternary composites markedly increased due to compatibilizition and protonation effect of the EAA. The SEM micrograph shows that the compatibility between the P(An‐co‐oAs)‐DBSA and the LLDPE matrix is enhanced after the introduction of EAA. The positive temperature coefficient of resistivity characteristic is observed. Tensile strength of P(An‐co‐oAs)‐DBSA/LLDPE/EAA composites is improved, compared with P(An‐co‐oAs)‐DBSA/LLDPE composites. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1511–1516, 2005
Electrical resistance response of poly(ethylene oxide)‐based conductive composites to organic vapors: Effect of filler content, vapor species, and temperature
Authors: Hu Ji Wen , Cheng Gen Shui , Zhang Ming Qiu , Li Ming Wei , Xiao Ding Shu , Chen Shi Guo , Rong Min Zhi , Zheng Qiang
Published: August 2005

In this work conductive composites consisting of carbon black (CB) and poly(ethylene oxide) were prepared by solution mixing. The composites' resistance drastically changes in organic vapors so that the composites can be used as candidates for gas‐sensing materials. Owing to the different conduction mechanisms and solvent/composites interactions, the electrical response behaviors of the composites exhibit specific dependences on CB content and environmental temperature, which were only reported previously in a few instances. In addition, the rate of response was also correlated with solvent polarity, solubility, etc. The findings would help to understand the micromechanism of response of the composites and to improve the sensing performance as well. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1517–1523, 2005
Polystyrene anchored vanillin Schiff base—Complexation and ion removal studies
Authors: Kumar Krishnapillai Girish , John Konnully Saji , Poduval Remalakshmy
Published: August 2005

A set of six new polystyrene anchored metal complexes have been synthesized by the reaction of the metal salt with the polystyrene anchored Schiff base of vanillin. These complexes were characterized by elemental analyses, Fourier transform infrared spectroscopy, diffuse reflectance studies, thermal studies, and magnetic susceptibility measurements. The elemental analyses suggest a metal : ligand ratio of 1 : 2. The ligand is unidentate and coordinates through the azomethine nitrogen. The Mn(II), Fe(III), Co(II), Ni(II), and Cu(II) complexes are all paramagnetic while Zn(II) is diamagnetic. The Cu(II) complex is assigned a square planar structure, while Zn(II) is assigned a tetrahedral structure and Mn(II), Fe(III), Co(II), and Ni(II) are all assigned octahedral geometry. The thermal analyses were done on the ligand and its complexes to reveal their stability. Further, the application of the Schiff base as a chelating resin in ion removal studies was investigated. The polystyrene anchored Schiff base gave 96% efficiency in the removal of Ni(II) from a 20‐ppm solution in 15 min, without any interference from ions such as Mn(II), Co(II), Fe(III), Cu(II), Zn(II), U(VI), Na+, K+, NH4+, Ca2+, Cl−, Br−, NO3−, NO2−,and CH3CO2−. The major advantage is that the removal is achieved without altering the pH. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1536–1539, 2005
Kinetic and thermodynamic studies of the isothermal curing reaction of the diglycidyl ether of bisphenol A/Ni(II) chelate system
Authors: Ghaemy M. , Omrani A. , Rostami A. A.
Published: August 2005

The curing reaction of a system consisting of a diglycidyl ether of bisphenol A (DGEBA) based epoxy and a new inorganic complex curing agent based on Ni(II) chelate with ethylendiamine (en) as a ligand was studied with an isothermal Fourier transform infrared (FTIR) technique. The hardener was prepared and characterized by means of FTIR spectroscopy, elemental analysis, and ICP–plasma techniques. The results of kinetic studies with two kinetic models, Horie et al. and Kamal, showed that the Kamal method gave the best fit to the experimental data. The overall values of the rate constants and activation energy for the DGEBA/Ni(en)3Br2 system were calculated. The activation energy of the curing process was also determined by an isoconversional method, which showed that with the progress of curing time, the activation energy increased. Further, the results obtained from thermodynamic studies give the entropy change of activation, which was more negative for the nth‐order path, whereas the activation heat of the reaction was more negative for the autocatalytic path. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1540–1547, 2005
Ring‐opening polymerization of ε‐caprolactone with a divalent samarium bis(phosphido) complex
Authors: Jiang Liming , Lou Liping , Sun Weilin , Xu Lina , Shen Zhiquan
Published: August 2005

The ring‐opening polymerization of ε‐caprolactone initiated with a divalent samarium bis(phosphido) complex [Sm(PPh2)2] is reported. The polymerization proceeded under mild reaction conditions and resulted in polyesters with number‐average molecular weights of 8.2 × 103 to 12.5 × 103. The yield and molecular weight of poly(ε‐caprolactone)s were dependent on the experimental parameters, such as the monomer/initiator molar ratio, the monomer concentration, the reaction temperature, and the polymerization time. The obtained polymers were characterized with Fourier transform infrared, NMR, gel permeation chromatography, and differential scanning calorimetry. On the basis of an end‐group analysis of low‐molecular‐weight polymers by NMR spectroscopy, a coordination–insertion mechanism is proposed for the polymerization. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1558–1564, 2005
Cellulose nanofibers prepared by the N‐methylmorpholine‐N‐oxide method
Authors: Kulpinski Piotr
Published: August 2005

The process of electrospinning is very suitable for obtaining fibers with a diameter on a nanometer scale. Such fibers can be spun from almost all kinds of known polymers, copolymers, and polymer blends. In this work, we present cellulose nanofibers obtained by the electrospinning process from spinning dopes containing cellulose dissolved in an N‐methylmorpholine‐N‐oxide/water system. Under different electrospinning process conditions, cellulose fibers, a nonwoven fiber network, and a cellulose membrane were obtained. The fibers were examined with scanning electron microscopy. The diameters of the fibers were in the submicrometer range. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1855–1859, 2005
Synthesis and characterization of polyamides X 18
Authors: Cui Xiaowen , Li Weihua , Yan Deyue , Yuan Cuiming , Di Silvestro Giuseppe
Published: August 2005

Step heating melt polycondensation was adopted in the preparation of polyamides based on 1,16‐octadecane diacid and α,ω(CH2)2n diamines (n = 1–6). The structure was confirmed by various spectroscopic techniques (IR, Raman, 1H‐NMR, and 13C‐NMR). High molecular masses were obtained only in the presence of an excess of diamine and when the diamine possessed low volatility. The molecular masses were between (0.94 and 2.1) × 104 Da for all polyamides under consideration. An excellent correlation between size exclusion chromatography and 1H‐NMR data was demonstrated in the measurement of the degree of polymerization. The melting temperatures of the polyamides decreased from polyamide 12 18 to polyamide 2 18 as the amide density along the molecular chain declined. No significant variation was observed in the glass‐transition and decomposition temperatures of the polyamides that were obtained. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1565–1571, 2005
Effect of intercalated hydrotalcite on swelling and mechanical behavior for poly(acrylic acid‐co‐N‐isopropylacrylamide)/hydrotalcite nanocomposite hydrogels
Authors: Lee Wen‐Fu , Chen Yung‐Chu
Published: August 2005

A series of nanocomposite hydrogels were prepared from acrylic acid (AA), N‐isopropylacrylamide (NIPAAm), and intercalated hydrotalcite (IHT) by photopolymerization. The influence of the intercalating content of 2‐acrylamido‐2‐methyl propane sulfonic acid (AMPS) in HT on the swelling and mechanical properties for poly(AA‐co‐NIPAAm)/IHT nanocomposite hydrogels was investigated. The results showed that the higher the content of the AMPS‐HT was, the higher the swelling ratio of the gels and the higher the content of the intercalating agent was, the lower swelling ratio. It was also demonstrated that the swelling ratio of the gel was not affected by the counterion in HT. The gel strength and crosslinking density were not enhanced by adding AMPS‐HT into the gel composition, but the maximum effective crosslink density and shear modulus of the nanocomposite hydrogels were increased with an increase of the content of the intercalating agent in HT. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1572–1580, 2005
Improving oxygen barrier properties of poly(ethylene terephthalate) by incorporating isophthalate. I. Effect of orientation
Authors: Liu R. Y. F. , Hu Y. S. , Hibbs M. R. , Collard D. M. , Schiraldi D. A. , Hiltner A. , Baer E.
Published: August 2005

The present study examined poly(ethylene terephthalate) (PET) and a series of statistical and blocky copolymers in which up to 30% of the terephthalate was replaced with isophthalate by copolymerization and melt blending, respectively. Some level of transesterification during processing of melt blends resulted in blocky copolymers, as confirmed by NMR. Random and blocky copolymers exhibited similar properties in the glassy state, including a single glass transition, due to miscibility of the blocks. However, random copolymerization effectively retarded cold‐crystallization from the glass whereas blocky copolymers readily cold‐crystallized to a crystallinity level close to that of PET. The polymers were oriented at four temperatures in the vicinity of the Tg and characterized by oxygen transport, wide‐angle X‐ray diffraction, positron annihilation lifetime spectroscopy, and infrared spectroscopy. Orientation of all the copolymers resulted in property changes consistent with strain‐induced crystallization. However, blocky copolymers oriented more easily than random copolymers of the same composition and after orientation exhibited slightly lower oxygen permeability, higher density, and higher fraction trans conformers. Analysis of oxygen solubility based on free volume concepts led to a two‐phase model from which the amount of crystallinity and the amorphous phase density were extracted. Dedensification of the amorphous phase correlated with the draw temperature. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1615–1628, 2005
Steady flow and dynamic viscoelastic behavior of nylon 1313 using parallel‐plate rheometer and capillary rheometer
Authors: Wang Yudong , Zhao Qingxiang , Liu Minying , Wang Zhimin , Liu Yukun , Cao Shaokui , Zhao Tianzeng
Published: August 2005

In this study, a novel nylon with long alkane segments (also called nylon 1313), which was synthesized using 1,13‐tridecanedioic acid in our laboratory, has been characterized. Different rheological behaviors of nylon 1313 have been presented using steady shear, creep recovery, and dynamic tests. The time‐temperature effects have also been investigated. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1643–1651, 2005
Cellulose fibers modified by silicon dioxide nanoparticles
Authors: Kulpinski Piotr
Published: August 2005

The sol–gel method is one of the most suitable ways for producing glasses, glass films, glass fibers, and glass nanoparticles. The relatively mild reaction conditions and simplicity of the sol–gel method make it an excellent tool for producing substances with precisely tailored properties. This technique opens the possibility for the synthesis of various new compounds, including pH sensors, ion sensors, bioactive nanoparticles, dyes carriers, and so forth. An attempt was made to combine the sol–gel technique with the advanced technology in the production of cellulose fibers in order to obtain fibers with new and unique properties. Cellulose fibers were prepared with N‐methylmorpholine‐N‐oxide as the direct solvent. The obtained fibers contained up to 30% (w/w) silicon dioxide nanoparticles. In order to observe the influence of the modifier on the fibers, their mechanical properties were examined. Modified fibers were also examined by means of thermogravimetry, wide‐angle X‐ray scattering, and 29Si‐NMR solid‐state spectroscopy. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1793–1798, 2005
Changes induced in silk‐like polyester properties by alkoxides treatment
Authors: Raslan W. M. , Bendak A.
Published: August 2005

The action of alkali treatment in both aqueous and alcoholic media is investigated to attain silk‐like polyester fabric. The use of alkoxide solutions is more effective on polyester fabric. Rapid loss in weight up to 15–20% occurs at ambient conditions. Immersion and padding techniques are applied. The effect of treatment on some properties of polyester fabric are given through measurements of tensile strength, drapability, permeability, density gradient, crystallinity, thermogravimetric analysis, and scanning electron microscopy. Optimization of the treatment conditions is also suggested. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1829–1837, 2005
Thermal aging properties and chemical resistance of blends of natural rubber and epoxidized low molecular weight natural rubber
Authors: Akinlabi A. K. , Okieimen F. E. , Aigbodion A. I.
Published: August 2005

Studies into solvent resistance and aging properties of blends of natural rubber and epoxidized low molecular weight natural rubber were carried out. Vulcanization of the blends using the semi‐efficient vulcanization (semi‐EV) system was found to have curing advantages over conventional vulcanization (CV) and efficient vulcanization (EV) systems. The rheological properties (cure time, t90, and scorch time, t2), solvent resistances, and aging properties of the vulcanizates were found to improve as the level of epoxidized low molecular weight natural rubber in the blends increases. The mechanical properties of the blends were also found to be within the accepted level for NR vulcanizates. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1733–1739, 2005
Morphological and electromechanical studies of fibers coated with electrically conductive polymer
Authors: Xue P. , Tao X. M.
Published: August 2005

Electrically conductive fibers have been prepared by polymerization of pyrrole on surfaces of commercial polymer fibers. Thickness and morphology of the conducting thin film on the surface of the fibers were examined by scanning probe microscopy, indicating a strong dependence of the substrate's nature, in addition to the processing conditions. Electromechanical property was investigated by an electromechanical testing system, showing that a smooth and uniform coating and the matched mechanical properties will lead to a satisfied performance of conductive fiber sensors. The difference in the behavior of two types of composite fibers was investigated by scanning electron microscopy in situ observations. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1844–1854, 2005
Static uniaxial compression of polyisoprene–montmorillonite nanocomposites monitored by 1H spin–lattice relaxation time constants
Authors: Poliskie G. M. , Cohen R. E. , Gleason K. K.
Published: August 2005

Previous work has focused on the use of microscopy to explore the mechanisms of deformation in polymer nanocomposites. That technique creates a qualitative representation that may not be statistically representative of the bulk properties. This paper illustrates the utility of solid‐state NMR, which inherently measures bulk behavior, to both identify and quantify mechanisms of deformation. Specifically, in this study, increases in the interfacial area of various modifications of Cloisite clay in 1,4‐cis polyisoprene nanocomposites were monitored during uniaxial compression. Interaction of the Fe+3 in the clay with the polymer decreases the polymer's 1H spin–lattice relaxation time constant (T1). In some of the nanocomposites, the increase in the interfacial area of the clay platelets was observed by a decrease in the polymer's T1 with successive amounts of strain. The observation of these changes with static 1H‐NMR is limited by the dispersion of the clay. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1806–1813, 2005
DNA‐loaded porous polyethersulfone particles for environmental applications II. Utilization
Authors: Zhao Changsheng , Yang Kaiguang , Wen Xian , Li Fan , Zheng Benxiang , Nomizu Motoyoshi , Nishi Norio
Published: August 2005

DNA‐loaded porous polyethersulfone (PES) particles are fabricated using a liquid–liquid phase separation technique. The particles are then used for environmental applications. Both the DNA‐loaded porous PES particles and the DNA‐loaded PES porous particle column could accumulate and remove DNA intercalating pollutants, such as ethidium bromide, acridine orange, endocrine disruptors, and heavy metal ions. The microsphere column shows more high removal efficiency. These results proved that the DNA‐loaded porous particles have the potential to serve as absorbents for environmental applications. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1674–1678, 2005
Biodegradable polymers based on renewable resources VIII. Environmental and enzymatic degradability of copolycarbonates containing 1,4 : 3,6‐dianhydrohexitols
Authors: Yokoe Makito , Aoi Keigo , Okada Masahiko
Published: August 2005

Environmental and enzymatic degradations were investigated on a series of copolycarbonates consisting of equimolar amounts of 1,4 : 3,6‐dianhydrohexitols (1,4 : 3,6‐dianhydro‐D‐glucitol (1a) and 1,4 : 3,6‐dianhydro‐D‐mannitol (1b)) and alkylene diols (1,4‐butanediol, 1,6‐hexanediol, 1,8‐octanediol, and 1,10‐decanediol) or oligo(ethylene glycol)s (di‐, tri‐, and tetraethylene glycols). Fourteen different copolycarbonates with number average molecular weights in the range of 1.1–4.2 × 104 were prepared by solution polycondensation as described in our previous article. Biodegradability of the copolycarbonates was assessed by soil burial degradation tests in composted soil at 27 °C and by enzymatic degradation tests in a phosphate buffer solution at 37 °C. In general, biodegradability of the copolycarbonates increased with increasing chain lengths of the methylene groups of alkylene diols or of the oxyethylene groups of the oligo(ethylene glycol)s. SEM observations of the film surfaces of polymers recovered from soil burial indicated that the copolycarbonates were degraded by microorganisms in soil. In enzymatic degradation, the copolycarbonates containing alkylene diol components showed high degradability with Pseudomonas sp. lipase, whereas the copolycarbonates containing oligo(ethylene glycol) components were not degraded at all. The enzymatic degradability of the copolycarbonates is discussed with reference to the geometrical structure around the carbonate linkages and the microstructure and hydrophobicity of the polymer chains. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1679–1687, 2005
Vulcanization kinetics of nitrile rubber/layered clay nanocomposites
Authors: Choi Dongcheol , Kader M. Abdul , Cho Baik‐Hwan , Huh Yang‐il , Nah Changwoon
Published: August 2005

Cure kinetic studies on nitrile rubber(NBR)‐layered clay nanocomposites, prepared by a melt mixing process, was investigated using a cure rheometer and differential scanning calorimeter (DSC). The characterization of the structure of the nanocomposites of uncured and cured samples was performed using X‐ray diffraction. The results showed that the interlayer spacing of cured nanocomposites was smaller than that of the uncured sample due to partial removal of organoclay from the interlayer spacing. The cure characterization showed a marked decrease in the scorch time of the NBR/organoclay system without affecting the optimum cure time and torque values due to the accelerating and plasticizing effect of organoclay. DSC analysis showed a reduction in cure time and increase in enthalpy of curing for the compounds added with organoclay. There was a little change in cure behavior of the NBR/unmodified clay system. NBR/clay nanocomposite showed the suitability of autocatalytic model for analyzing the cure parameters of rubber/clay nanocomposites. The activation energy of curing of NBR/O‐MMT nanocomposites was lower than that of pristine NBR. The kinetic parameters determined from the model equation showed close fitting with the experimental results, indicating the suitability of autocatalytic model for cure characterization. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1688–1696, 2005
Synthesis and photopolymerization of oxetanes derived from bisphenol A
Authors: Verstegen E. J. K. , Kloosterboer J. G. , Lub J.
Published: August 2005

A series of new dioxetanes derived from bisphenol A has been synthesized. Polymers were obtained by photopolymerization. The polymerization shrinkage of these relatively fast polymerizing dioxetane monomers was <3%, much less than that of dimethacrylates of a comparable molecular weight. The rates of polymerization compare favorably with that of the diglycidylether of bisphenol A, which also exhibits a low shrinkage. The relationship between the chemical structure and the temperature of maximum mechanical loss was investigated. Some of the new polymers exhibit temperatures of maximum mechanical loss sufficiently high to be useful for precision optical components made by photoreplication. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1697–1707, 2005
Degradation of acrylonitrile–ammonium itaconate copolymers
Authors: Hou Chen , Qu Rongjun , Qun Wang , Ying Liang , Wang Chengguo
Published: August 2005

Acrylonitrile–ammonium itaconate copolymers were prepared by H2O/dimethyl formamide suspension polymerization technique. Differential scanning calorimetry results of the degradation of acrylonitrile–ammonium itaconate copolymers in air are presented. The apparent activation energy of degradation of the copolymer was calculated using the Kissinger method. Effects of copolymerization conditions on the apparent activation energy of copolymer were studied. Increasing the dimethyl formamide concentration in the solvent mixture leads to a rapid increase in the degradation apparent activation energy of acrylonitrile–ammonium itaconate copolymer. The value of the degradation apparent activation energy of the copolymer synthesized in dimethyl formamide solvent increases up to 168.3 kJ mol−1. The apparent activation energy decreases quickly along with an increase in ammonium itaconate concentration, and this change becomes less prominent as the weight ratio of ammonium itaconate/acrylonitrile goes beyond 6/94, ΔEa = 89.4 ± 2.0 kJ mol−1. The apparent activation energy shows a trend of increase with increasing copolymerization temperature. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1708–1711, 2005