bluuebunny/crossref_metadata_2025 huggingface dataset:
Férfiak és nők a munka világában. Nemi szerepek a munkahelyen
Authors: Nguyen Luu Lan Anh
Published: May 2005

A nők karrierlehetőségeinek lassú, de biztosnak tűnő bővülése ellenére még mindig nyilvánvaló a munkapiaci nemi szegregáció, a fizetésbeli különbség, a nők elenyésző jelenléte a vezetés felsőbb szintjein. A releváns szakirodalom áttekintésével a tanulmány bemutatja a munkahelyi egyenlőtlenségek lehetséges magyarázatait és a változtatás néhány lehetőségét. A vélt vagy az eltérő szocializáció során kialakult tényleges nemi különbségek, a nemi sztereotípiák és nemi szerepelvárások, illetve a szervezeti sajátosságok együttesen, egymást áthatva fejtik ki hatásukat a nők és a férfiak eltérő munkapiaci helyzetére, előidézve a nemi szegregációt, az üvegplafon- vagy éppen az üvegfaljelenséget. A tanulmány kitér azokra a kihívásokra, amelyekkel elsősorban a női munkavállalónak, különösen a vezetői pozícióban levő nőknek kell szembenézniük és amelyekkel csak kisebb mértékben vagy egyáltalán nem találkoznak a férfiak. Meg kell találniuk a kényes egyensúlyt egyrészt a sokszor egymással nehezen összeegyeztethető, családdal kapcsolatos teendők és a munka között, másrészt a női és a vezető szerepnek való megfelelés egymásnak ellenmondó követelményei között. A fentiek elemzésében jelentős szerepet kap a társadalmi nem és a státus, a hatalom közötti viszony, valamint ennek hatása a nők munkapiaci helyzetére.
A méretnövekedésből származó konfliktusok
Authors: Tóth Györgyi
Published: May 2005

A tanulmány a szervezeti növekedés humán aspektusait vizsgálja. A létszám növekedése a vállalat szinte minden területén jelentős változást okoz az egyén számára, hiszen változik a szervezeti struktúra, ami hatással van a kommunikációra, a személyes kapcsolatokra, a munkával való elégedettségre, a munkamegosztásra is. Az egyén számára a változás egyaránt jár pozitív és negatív következményekkel. Egy elővizsgálat keretében került felmérésre, hogy a szervezet mérete alapján mely területeken jelenik meg eltérés a kisebb, illetve nagyobb cégek dolgozóinak megítélésében, illetve milyen előnyökkel és hátrányokkal jellemezhetők a kisebb, illetve nagyobb vállalatok. Az elővizsgálatban nyert eredményekre épül a tanulmány második vizsgálata, mely a növekedés egyénre gyakorolt hatását igyekszik tetten érni. A fő vizsgálat alapfeltevése az, hogy a létszámnövekedést a szervezet tagjai összességében inkább negatívan élik meg. Az eredmények megerősítik a kiinduló hipotézist, annak ellenére, hogy a növekedés során a nagyvállalatok előnyeit is megemlítik a megkérdezettek. A vizsgálatok alapján feltételezhető, hogy a személyes kapcsolatok megromlása és a változással szembeni ellenállás együttesen tehető felelőssé a növekedés ilyen negatív megítéléséért.
A teljesítményértékelő rendszerrel kapcsolatos attitűdök feltárása egy magyar nagyvállalatnál
Authors: Domján Mónika
Published: May 2005

A Richter Gedeon Vegyészeti Gyár Rt.-nél 2000-ben került sor a teljesítményértékelő rendszer - röviden TÉR - bevezetésére. A vizsgálatok elvégzése idején, 2001 tavaszán a második értékelés zajlott le a vállalatnál, ezért 2001-ben a „monitorozás” során elsősorban arra koncentráltunk, hogy feltárjuk a rendszerrel szembeni ellenállás mögött meghúzódó tényezőket. A visszajelzések, vélemények begyűjtésére kiscsoportos beszélgetéseket szerveztünk, majd az ott felvetődött témák alapján kérdőíves vizsgálatot végeztünk, amely a teljesítményértékelő rendszerrel kapcsolatos attitűdök feltárását célozta. Ebben az írásban az elméleti ismeretek és a gyakorlati tapasztalatok alapján levonható következtetések és tanulságok kerülnek megfogalmazásra.
Grasping the connectivity of random functional graphs
Authors: Romero David , Zertuche Federico
Published: May 2005

Afunctional graphis a directed graph where every node has out-degree one (loops allowed). This paper deals with connectivity aspects of random functional graphs, like the expected number and size of connected components, cycles, and trajectories. Both exact and asymptotic formulas are provided.
On an extension of the Hardy-Hilbert theorem
Authors: Weijian J. , Mingzhe G. , Xuemei G.
Published: May 2005

A weighted Hardy-Hilbert’s inequality with the parameter
λ
of form \documentclass{aastex}
\usepackage{amsbsy}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{bm}
\usepackage{mathrsfs}
\usepackage{pifont}
\usepackage{stmaryrd}
\usepackage{textcomp}
\usepackage{upgreek}
\usepackage{portland,xspace}
\usepackage{amsmath,amsxtra}
\usepackage{bbm}
\pagestyle{empty}
\DeclareMathSizes{10}{9}{7}{6}
\begin{document}
$$\sum\limits_{m = 1}^\infty {\sum\limits_{n = 1}^\infty {\frac{{a_m b_n }}{{(m + n)^\lambda }}} < B^* (\lambda )\left( {\sum\limits_{n = 1}^\infty {n^{1 - \lambda } a_{a_n }^p } } \right)^{{1 \mathord{\left/ {\vphantom {1 p}} \right. \kern-\nulldelimiterspace} p}} \left( {\sum\limits_{n = 1}^\infty {n^{1 - \lambda } b_n^q } } \right)^q }$$
\end{document} is established by introducing two parameters s and λ, where \documentclass{aastex}
\usepackage{amsbsy}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{bm}
\usepackage{mathrsfs}
\usepackage{pifont}
\usepackage{stmaryrd}
\usepackage{textcomp}
\usepackage{upgreek}
\usepackage{portland,xspace}
\usepackage{amsmath,amsxtra}
\usepackage{bbm}
\pagestyle{empty}
\DeclareMathSizes{10}{9}{7}{6}
\begin{document}
$$\tfrac{1}{p} + \tfrac{1}{q} = 1,p \geqq q > 1,1 - \tfrac{q}{p} < \lambda \leqq 2,B^* (\lambda ) = B(\lambda - (1 - \tfrac{{2 - \lambda }}{p}),1 - \tfrac{{2 - \lambda }}{p})$$
\end{document} is the beta function.
B
*(λ) is proved to be best possible. A stronger form of this inequality is obtained by means of the Euler-Maclaurin summation formula.
Graph of unbounded multipliers
Authors: Amini Massoud
Published: May 2005

We consider the unbounded operators affiliated with a C*-algebra and study the problem of when these elements belong to the (unbounded) multiplier algebra of the Pedersen's ideal of the C*-algebra.
A sharp estimate for multilinear Bochner-Riesz operator
Authors: Wu B. S. , Liu L. Z.
Published: May 2005

We establish a sharp estimate for some multilinear operator related to Bochner--Riesz operator. As an application, we obtain the weighted norm inequality and L log L type estimate for the multilinear operator.
New upper bounds on Enomoto Katona’s coding type problem
Authors: Quistorff J.
Published: May 2005

Let
n, k
∈ ℕ with
2k
≦
n
and
X
be an
n
-set. Consider the space \documentclass{aastex}
\usepackage{amsbsy}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{bm}
\usepackage{mathrsfs}
\usepackage{pifont}
\usepackage{stmaryrd}
\usepackage{textcomp}
\usepackage{upgreek}
\usepackage{portland,xspace}
\usepackage{amsmath,amsxtra}
\usepackage{bbm}
\pagestyle{empty}
\DeclareMathSizes{10}{9}{7}{6}
\begin{document}
$$\mathcal{R}: = \left\{ {\{ A,B\} \subseteqq \left( {_k^X } \right)|A \cap B = \not 0} \right\}$$
\end{document} equipped with \documentclass{aastex}
\usepackage{amsbsy}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{bm}
\usepackage{mathrsfs}
\usepackage{pifont}
\usepackage{stmaryrd}
\usepackage{textcomp}
\usepackage{upgreek}
\usepackage{portland,xspace}
\usepackage{amsmath,amsxtra}
\usepackage{bbm}
\pagestyle{empty}
\DeclareMathSizes{10}{9}{7}{6}
\begin{document}
$$d^\mathcal{R} (\{ A,B\} ,\{ S,T\} ): = \min \{ |A\backslash S| + |B\backslash T|,|A\backslash T| + |B\backslash S|\} .$$
\end{document} Given
d
∈ ℕ with
d
≦
2k
, the coding type problem is the determination of the maximum cardinality of a subset
C
⊆
R
with
dR
({
A, B
}, {
S, T
}) ≧
d
for all distinct {
A, B
}, {
S, T
} ∈
C
. Here new upper bounds on this problem are given. Some are modifications of a well-known bound, some are based on ideas of classical coding theory in the Hamming space. New records are achieved if
n
is small relative to fc, the diameter of (
R,dR
) is determined and tables with the presently known best upper bounds are given.
On the generalizations of the polar inertia momentum of the closed curves obtained kinematically
Authors: Yüce S. , Düldül M , Kuruoğu N.
Published: May 2005

In this paper we give some general results for the polar inertia momentums, given by [2], of the closed orbit curves obtained during the one-parameter closed planar motions.
On the correlation of binary sequences
Authors: Gyarmati Katalin
Published: May 2005

C. Mauduit conjectured that C2(E)CN3(EN) ?? Nc always holds with some constant 1/2< c = 1. This will be proved for c=2/3, more exactly if for a sequence EN =C {-1,+1}N we have C2 (EN) << N2/3 then  C3 (EN) ??  N1/2. Indeed, a more general theorem is proved, involving correlation measures.
A note on the fractional calculus in Banach spaces
Authors: Salem Hussein A. H. , El-Sayed A. M. A. , Moustafa O. L.
Published: May 2005

O'Regan fixed point theorem is used to establish an existence result for the fractional order integral equation x(t) = g(t)+ ?Iaf(.,x(.))(t), t?[0,1], a ? 0, where the vector-valued functionf is nonlinear weakly-weakly continuous. Moreover, existence of weak solutions to the Cauchy problem  dx/dt = f(t, x (t)), t ? [0,1], x(0) = x0, is obtained as a corollary.
Endpoint estimates for multilinear operators of some sublinear operators on Herz and Herz type Hardy spaces
Authors: Liu L.
Published: May 2005

In this paper the endpoint estimates for some multilinear operators related to certain sublinear integral operators on Herz and Herz type Hardy spaces are obtained. The operators include Littlewood-Paley operator and Marcinkiewicz operator.
Asymptotic formulas for Dirichlet boundary value problems
Authors: Yilmaz Bülent , Veliev O. A.
Published: May 2005

In this article we obtain asymptotic formulas of arbitrary order for eigenfunctions and eigenvalues of the nonselfadjoint Sturm-Liouville operators with Dirichlet boundary conditions, when the potential is a summable function. Then using these we compute the main part of the eigenvalues in special cases.
Almost sure limit theorems for random allocations
Authors: Fazekas István , Chuprunov Alexey
Published: May 2005

Almost sure limit theorems are presented for random allocations. A general almost sure limit theorem is proved for arrays of random variables. It is applied to obtain almost sure versions of the central limit theorem for the number of empty boxes when the parameters are in the central domain. Almost sure versions of the Poisson limit theorem in the left domain are also proved.
On the approximation of quadratic algebraic numbers
Authors: H.-Molnár Sándor
Published: May 2005

In the paper we construct such second order linear recursive sequences G and H of rational integers that with their terms |a -Gn+1 /H n| < 1/ (\sqrtvDH2n) holds for every positive integer n, where a denotes a real quadratic algebraic integer of discriminant D. An approximating sequence of the form Gn+1 /Hn is also given for a  if it is only a real quadratic algebraic number (not an algebraic integer), but in this case the approximating constant is not the best.
A method to find the best bounds in a multivariate discrete moment problem if the basis structure is given
Authors: Mádi-Nagy Gergely
Published: May 2005

The multivariate discrete moment problem (MDMP) is to find the minimum and/or maximum of the expected value of a function of a random vector which has a discrete finite support.  The probability distribution is unknown, but some of the moments are given. The MDMP has been initiated by Prékopa who developed a linear rogramming methodology to solve it. The central results in this respect concern the structure of the dual feasible bases. These bases provide us with bounds without any numerical difficulty (which is arising in the usual solution methods). In this paper we shortly summarize the properties of the above mentioned basis structures, and then we show a new method which allows us to get the basis corresponding to the best bound out of the known structures by optimizing independently on each variable. We illustrate the efficiency of this method by numerical examples.
Closures of discrete sets in compact spaces
Authors: Dow Alan
Published: May 2005

We consider the question of whether a compact space will always have a discrete subset whose closure has the same cardinality as the whole space. We obtain many positive results for compact spaces of countable tightness and a consistent negative result for a space of tightness and density ?1.
On the rate of convergence of some integral operators for functions of bounded variation
Authors: Agratini Octavian
Published: May 2005

In the present paper we define a general class Bn,a, a =1, of Durrmeyer-Bézier type of linear positive operators. Our main aim is to estimate the rate of pointwise convergence for functions f at those points x at which the one-sided limits f(x+) and f(x-) exist. As regards these functions defined on an interval J certain conditions are required. We discuss two distinct cases: Int (J)=(0,8) and Int (J)=(0,1).
Assaying Aspects of Attention and Impulse Control in Mice Using the 5‐Choice Serial Reaction Time Task
Authors: Humby Trevor , Wilkinson Lawrence , Dawson Gerry
Published: May 2005

First developed in the 1980s by Trevor Robbins in Cambridge to investigate attentional function in rats, the 5‐choice serial reaction time task involves continuous scanning by the subject across a spatial array of visual stimuli. On detecting a brief stimulus at one of five locations, the subject must make a nose poke in order to collect a reward. The task has also been conducted successfully in several strains of mice, including transgenic models. This unit presents the procedures required to run the task in mice, outlining the expected results at each stage of training and presenting examples of the most common manipulations used to dissociate behavior further.
Chemoconvulsant Model of Chronic Spontaneous Seizures
Authors: Hellier Jennifer L. , Dudek F. Edward
Published: May 2005

Animal models of injury‐induced epilepsy may provide insight into the mechanisms of acquired epilepsy. Previous animal models of temporal lobe epilepsy (TLE) were produced by acute treatments that often have high mortality rates and/or are associated with a low proportion of animals developing spontaneous, chronic motor seizures. In this unit, a protocol is provided for inducing chronic epilepsy in rats using multiple, low‐dose, intraperitoneal injections of an excitotoxic agent, kainic acid. This protocol reliably induces TLE in nearly all treated rats (97% had at least two observed spontaneous motor seizures) with a relatively low mortality rate (<15%). This modified chemoconvulsant treatment protocol (i.e., multiple low doses) is efficient and relatively simple, and the properties of the chronic epileptic state appear similar to those of severe human TLE.
Rule Out (R/O) Arteriovenous Malformation
Authors: Conrad L. Kirkland , Thibodeau Steven , Grant Ellen
Published: May 2005

When imaging patients for intracranial arteriovenous malformations, the goals are: (1) to determine if an arteriovenous malformation is present; (2) to assess size, shape, and location of the nidus; (3) to determine potential arterial feeders and venous drainage routes (including screening for aneurysms on arterial feeders); and (4) to determine the state of the surrounding brain parenchyma, including the identification of intracranial hemorrhage. A post‐contrast 3‐D spoiled gradient echo (SPGR) sequence is used for sequences 1 to 3. Standard MR imaging sequences are used to evaluate the brain parenchyma. The protocol contained within this unit can be used for the evaluation of stable patients. In order to perform the optional sequences with perfusion and diffusion studies, a scanner with echoplanar capabilities is required; however, the standard anatomical MR imaging sequences included in the protocols do not require these faster gradients.
Preparation, Culture, and Immortalization of Mouse Embryonic Fibroblasts
Authors: Xu Jianming
Published: May 2005

Genetically manipulated transgenic and gene‐targeted mouse models are indispensible tools used in defining the role of genes in development and organ function. Similarly, cells isolated from these mice bear the same genetic alterations and therefore can be extremely useful for studying the molecular and cellular mechanisms and regulatory gene networks involving the mutated gene under well defined culture conditions. In this unit, detailed protocols regarding isolation of mouse embryonic fibroblasts (MEFs) from mouse embryos, culture of MEFs, and immortalization of MEFs are described. These protocols should be particularly useful to those investigators who intend to establish primarily cultured MEFs and to immortalize primary MEFs into stable cell cultures with a permanent growth feature from wild‐type and mutant mouse embryos.
Isolation and Immortalization of Lymphocytes
Authors: Ling Paul D. , Huls Helen M.
Published: May 2005

Recent advances in Genomics and Proteomics have necessitated a constant supply of DNA derived from specific genotypes. Lymphoblastoid cell lines (LCLs) are of great practical value as an unlimited source of stable genomic DNA and viable cells, which can be used to perform a variety of biochemical and molecular studies. LCLs are typically generated by infection of primary lymphocytes with Epstein‐Barr virus (EBV). In this unit, we describe simple procedures for production of EBV, isolation of lymphocytes, EBV infection of lymphocytes, and isolation of the resulting LCLs.
Metaphase Chromosome Preparation from Cultured Peripheral Blood Cells
Authors: Bangs Charles D. , Donlon Timothy A.
Published: May 2005

Chromosome preparations currently provide the only direct view of the genome as a whole. Although molecular methods allow a more detailed analysis of specific regions of the genome, the study of genetics is not complete without an appreciation of the metaphase cell. The stimulated T cell system described in this unit is the most widely used means of obtaining large numbers of mitotic cells for genetic analyses. Synchronization of the cell cycle in culture is described, combined with direct inhibition of chromosome condensation, to yield longer high‐resolution prophase or prometaphase preparations. Such preparations are used for detailed analysis of microdeletions or subtle rearrangements, fine breakpoint analysis, and refined mapping. Microscope slide preparation of mitotic chromosomes from harvested cell culture suspensions is also explained in the support protocol.
ZAP‐70 Staining in Chronic Lymphocytic Leukemia
Authors: Villamor Neus
Published: May 2005

Chronic lymphocytic leukemia (CLL) is the most common chronic leukemia in Western countries. The disease has an extremely variable clinical course, and several prognostic features have been identified to assess individual risk. The configuration of the immunoglobulin variable heavy‐chain gene (IgVH) is a strong predictor of the outcome. CLL patients with unmutated IgVH status have an aggressive clinical course and a short survival. Unfortunately, analysis of IgVH gene configuration is not available in most clinical laboratories. A small number of genes are differentially expressed between unmutated IgVH and mutated IgVH clinical forms of CLL. One of these genes is ZAP‐70, which is detected in leukemic cells from patients with the unmutated IgVH form of CLL. Flow cytometry presents advantages over other methods to detect ZAP‐70, and its quantification by flow cytometry has proved its predictive value. This unit focuses on protocols to quantify ZAP‐70 by flow cytometry in CLL.
Three‐Dimensional Visualization of Blood and Lymphatic Vasculature in Tissue Whole Mounts Using Confocal Microscopy
Authors: Eichten Alexandra , Jennifer Shen H.‐C. , Coussens Lisa M.
Published: May 2005

Two vascular systems, cardiovascular and lymphatic, maintain appropriate interstitial and intravascular fluid volume in the body. Each is endowed with innate physiologic response capabilities activated upon tissue or organ “damage.” Chronic activation following pathologic assault, however, can contribute to pathogenesis. Three‐dimensional visualization of vasculature in whole tissues using confocal microscopy is a valuable tool for examining cellular and architectural changes accompanying altered vascular function. The relative affinities of plant lectins for carbohydrate moieties present on luminal surfaces of endothelial cells can be used to characterize endothelium in distinctive physiologic and pathologic states. Perivascular cells that wrap around blood endothelial cells can be visualized using antibodies immunoreactive with α‐smooth muscle actin. Similarly, lymphatic endothelial cells can be detected by antibodies immunoreactive to the hyaluronan receptor LYVE‐1. Together, these approaches allow functional and morphological analysis of blood vasculature distinct from endothelial cells within the lymphatic vascular network and surrounding support cells.
Cover Picture: Microscopic Evidence for Spatially Inhomogeneous Charge Trapping in Pentacene (Adv. Mater. 11/2005)
Authors: Muller E. M. , Marohn J. A.
Published: May 2005

Trapped charge has been observed in polycrystalline pentacene films by electric force microscopy in work reported by Muller and Marohn on p. 1410. The cover shows an optical fiber watching the motion of a metal‐coated cantilever hovering over a polycrystalline pentacene film. The film occupies the 6.5  μm gap in a working field‐effect transistor. Trapped charge (dark blue and black areas in the pentacene) appears as large patches randomly distributed throughout the device, implying that long‐lived traps in polycrystalline pentacene are not correlated with grain boundaries.
Inside Front Cover: Polarized‐Light‐Emitting Quantum‐Rod Diodes (Adv. Mater. 11/2005)
Authors: Hikmet R. A. M. , Chin P. T. K. , Talapin D. V. , Weller H.
Published: May 2005

Polarized‐light‐emitting quantum‐rod diodes have been successfully produced using thin layers of quantum rods oriented by a rubbing technique, as shown on the inside cover. Hikmet and co‐workers report on p. 1436 that diode emission at 620 nm with a luminance efficiency of 0.65 cd A–1 and an external quantum efficiency of 0.49 % is obtained. Light emitted polarized parallel to the long axis of the rods is 1.5 times more intense than that polarized perpendicular to the rods.
Titelbild: Confined Electron‐Transfer Reactions within a Molecular Metal Oxide “Trojan Horse” (Angew. Chem. 22/2005)
Authors: Long De‐Liang , Abbas Hamera , Kögerler Paul , Cronin Leroy
Published: May 2005

Bei thermischer Stimulation scheiden die beiden Templat‐Sulfitionen, die in den im Titelbild gezeigten, als “Trojanisches Pferd” fungierenden Polyoxometallatcluster eingebettet sind, Elektronen‐“Soldaten” an die Clusteroberfläche ab, wobei die Farbe der Verbindung von Farblos nach Blau umschlägt (Hintergrund). Die partielle Reduktion der Clusterhülle erfolgt parallel zur Oxidation der Sulfit‐ zu Sulfationen. Einzelheiten zu dieser gekoppelten strukturellen und elektronischen Umlagerung finden sich in der Zuschrift von L. Cronin et al. auf S. 3481 ff.
Cover Picture: Confined Electron‐Transfer Reactions within a Molecular Metal Oxide “Trojan Horse” (Angew. Chem. Int. Ed. 22/2005)
Authors: Long De‐Liang , Abbas Hamera , Kögerler Paul , Cronin Leroy
Published: May 2005

Upon thermal stimulation the two templating sulfite anions embedded in the “Trojan Horse” polyoxometalate cluster shown in the cover picture release electron “soldiers” to the cluster's surface, turning the cluster from colorless to blue (background). The formation of the mixed‐valence cluster shell is commensurate with the oxidation of the sulfite to sulfate anions. More details about this coupled structural and electronic rearrangement are given in the Communication by L. Cronin et al. on page 3415 ff.
Thermal behavior and morphology of polycaproamide (PCA)/cationic dyeable polycaproamide (CD‐PCA) polyblended filaments
Authors: Hsiao Keven , Jue Zhi‐Feng , Tsen Wen‐Chin , Shu Yao‐Chi
Published: May 2005

Polycaproamide (PCA) polymer and cationic dyeable polycaproamide (CD‐PCA) polymer were blended mechanically in the proportions of 75/25, 50/50, and 25/75 in a melt twin‐screw extruder to prepare three PCA/CD‐PCA polyblended polymers. Blends of PCA and CD‐PCA were spun into filaments. The molar ratio of 5‐sodium sulfonate dimethyl isophthalate (5‐SSDMI) for CD‐PCA polymer was 1.99%. This study investigated the physical properties of PCA/CD‐PCA polyblended filaments using gel permeation chromatograph (GPC), nuclear magnetic resonance (NMR), gas chromatography (GC), potentiometer, thermogravimetric analysis (TGA), a rheometer, differential scanning calorimetry (DSC), the density gradient method, wide‐angle X‐ray diffraction (WAXD), extension stress‐strain measurement, and scanning electron microscope (SEM). Flow behavior of PCA/CD‐PCA polyblends exhibited positive‐deviation blends (PDB), and the 50/50 blend of PCA/CD‐PCA showed a maximum value of the melt viscosity. Experimental results of the DSC indicated PCA and CD‐PCA molecules easily formed miscible domains. The crystallinities of PCA/CD‐PCA polyblended filaments decreased as the 5‐SSDMI content increased. Tenacities/densities of PCA/CD‐PCA polyblended filaments were also found to decline as the 5‐SSDMI content increased. The surface of PCA/CD‐PCA polyblended filament exhibited a uniform morphology from the SEM data. PCA and CD‐PCA polymers were proved to be a compatible system. The weight loss percentages of the PCA/CD‐PCA polyblended filaments increased as the 5‐SSDMI content increased in aqueous NaOH solution. The porous morphology of a larger size from 0.01 to 2 μm in diameter was observed after alkali treatment of PCA/CD‐PCA polyblended filament. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1220–1226, 2005
Multiscale morphological analysis of commingled PP/unidirectional glass fiber composites: Experiment and theory
Authors: Dubouloz‐Monnet F. , Mélé P. , Albérola N. D.
Published: May 2005

Quantitative 2D image processing has been performed to assess the morphology of commingled polypropylene composites reinforced by a range of glass fiber contents. Quantitative morphological probes, derived from both local and global analyses, point out the heterogeneous dispersion of unidirectional fibers within the polymer matrix, i.e., the presence of aggregates. It is found that more than 86% of fibers are packed into aggregates at a maximum packing fraction of 0.84 whatever the filler content. Moreover, accounting for these morphological characteristics and based on the percolation concept, prediction of the morphology behavior of such composites is proposed. A good agreement between theory and experiment is found. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1038–1050, 2005
Rheological behavior of polymer melts with natural fibers
Authors: Steller Ryszard T.
Published: May 2005

Flow behavior of polymer liquids filled with short fibers (particulate fillers) was theoretically analyzed from the point of view of the free volume theory. Assuming that the filler addition changes the occupied volume, while the temperature variations cause mainly the free volume changes, a general expression describing the viscosity of the system as a function of the filter content, temperature variations, and rheological properties of the pure polymer liquid was derived. If the viscosity curve of the unfilled polymer is described by the Carreau equation, the corresponding viscosity curve of the filled polymer is also represented by an equation of Carreau type. However, this equation has other values of Newtonian viscosity and the power exponent in comparison with the initial equation. Both parameters depend on the filler content and temperature. The derived equation predicts a viscosity rise and a stronger non‐Newtonian behavior of the system with increasing filler content. The temperature rise exerts an opposite effect on the rheological behavior. The theoretical predictions are in good accordance with viscosity measurements for low‐density polyethylene and polystyrene melts filled with short cotton, flax, and hemp fibers. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1401–1409, 2005
Evaluation of Alfa grass soda lignin as a filler for novolak molding powder
Authors: Hattali Samir , Benaboura Ahmed , Dumarçay Stéphane , Gérardin Philippe
Published: May 2005

Behavior of Alpha grass soda lignin was investigated for the preparation of novolak molding powders. Thermal analysis of the different investigated formulations indicated that molding powders prepared from Alpha grass soda lignin were more resistant to thermal degradation compared to a standard formulation prepared from wood flour. Limiting oxygen index determined for the different composites confirmed the higher thermal stability of Alpha grass soda lignin composites. Mechanical properties tested either from Shore hardness tests or from impact strength measurements revealed a slight decrease of mechanical properties for composites prepared from Alpha grass soda lignin. All these results showed the possibility to replace imported wood flours by locally available Alpha grass soda lignin to obtain phenolic composites with quite similar properties. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1065–1068, 2005
Antimicrobial finishing of acrilan fabrics with cetylpyridinium chloride: Affected properties and structures
Authors: Cai Zaisheng , Sun Gang
Published: May 2005

Durable antimicrobial acrilan fabrics were prepared by using cetylpyridinium chloride (CPC) in a chemical finishing process. The CPC could form ionic interactions with anionic groups on acrilan fibers, which contribute to durable antimicrobial functions. Reaction conditions such as pH, temperature, and time of the chemical treatment affected exhaustion of CPC and antimicrobial properties. However, the pH conditions of the finishing bath also impacted mechanical properties and color of the fabrics, particularly under alkaline conditions. Although a more alkaline condition is preferred for durable antimicrobial functions, high pH reduces tensile strength and results in yellowing of acrilan fibers. The yellowing of the acrilan fibers is caused by the hydrolysis of acrylonitrle groups and induced formation of conjugated CN systems in the polymers. The conjugated systems were characterized by FTIR. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1227–1236, 2005
Proton‐exchange membranes via the grafting of styrene and acrylic acid onto fluorinated ethylene propylene copolymer by a preirradiation technique. III. Thermal and mechanical properties of the membranes and their sulfonated derivatives
Authors: Phadnis S. , Patri M. , Chandrasekhar L. , Deb P. C.
Published: May 2005

Polymer electrolyte membranes were prepared via the grafting of styrene and acrylic acid onto fluorinated ethylene propylene copolymer with a preirradiation technique and subsequent sulfonation. The thermal and mechanical properties of the grafted membranes and their sulfonated derivatives were dependent on the degree of grafting. The grafted membranes showed a two‐step degradation pattern, whereas their sulfonated derivatives showed a three‐step degradation pattern. The glass‐transition temperature and crystallinity percentage of the membranes were determined with differential scanning calorimetry. With an increase in the degree of grafting and sulfonation, the glass‐transition temperature increased, whereas the crystallinity percentage decreased. The tensile strength and elongation decreased with the degree of grafting and sulfonation. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1418–1425, 2005
Synthesis of amphiphilic graft copolymers of SBS with acrylamide and study of their properties
Authors: Xie Hong‐Quan , Deng Ji‐Chen , Xie Dong
Published: May 2005

Graft copolymerization of SBS in the form of sodium ionomer with acrylamide in emulsion using benzoyl peroxide as initiator and sodium ionomer of maleated SBS as a self‐emulsifier, which can form a stable cyclohexane/water emulsion with AM without using any other emulsifier, was carried out. Factors affecting the graft copolymerization were studied. The grafting % can reach about 15%. Emulsifying properties of sodium ionomer of maleated SBS and the graft copolymer, as well as the compatibilizing effect of the graft copolymer in blending polyvinyl chloride (PVC) with SBS, were studied. The sodium ionomer of maleated SBS, the graft copolymers, and the blends were characterized with IR and DSC. The results showed that water absorbency and emulsifying volume increase obviously after graft copolymerization with AM. 0.2 g of the graft copolymer containing 14 wt % PAM grafts can emulsify a mixture of 30 mL toluene and 70 mL water completely. The graft copolymer can be used as an effective compatibilizer in the blending of PVC and SBS, more effective than the sodium ionomer of maleated SBS. Only 2 wt % of the copolymer based on the blend used in blending is enough to raise the tensile strength three times. The blends with weigh ratios of PVC/SBS at 3/7–4/6 in the presence of the graft copolymer behave as thermoplastic elastomers with a tensile strength of 14 MPa, an ultimate elongation of 750%, and a permanent set of 17%. Glass transition temperatures of the blend shifted inward in the presence of the graft copolymer. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1248–1253, 2005
Copolymerization of glycidol with functionalized phenyl glycidyl ethers
Authors: Royappa A. Timothy , McDaniel Randall L.
Published: May 2005

Various copolymers of glycidol with phenyl‐containing comonomers (glycidyl 2‐methylphenyl ether, 2‐biphenylyl glycidyl ether, 4‐tert‐butylphenyl glycidyl ether, methoxyphenyl glycidyl ether, and p‐nitrophenyl glycidyl ether) were synthesized by cationic ring‐opening polymerization, for possible use as nanoparticle coatings. The copolymerization involving p‐nitrophenyl glycidyl ether produced p‐nitrophenol as a byproduct. The copolymers were found to have relatively low average molecular weights and high polydispersities, with glass‐transition temperatures in the −20 to +10°C range (approximately). © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1462–1466, 2005
Synthesis and characterization of a kind of poly(3‐butylthiophene methine) with azo side groups
Authors: Meng Ling‐Jie , Wu Hong‐Cai , Gao Chao , Yi Wen‐Hui
Published: May 2005

To enhance the third nonlinear optical properties of poly(thiophene methine), we synthesized a new kind of poly(3‐butylthiophene methine) with azo side groups: poly[(3‐butylthiophene‐2,5‐diyl)‐p‐(N,N‐dimethylamino)azobenzylidenequinomethane] (PBTDMABQ). PBTDMABQ and its intermediate product were characterized with IR, ultraviolet–visible, and 1H‐NMR spectroscopy. The band gaps of PBTDMABQ were calculated to be 1.94 and 2.06 eV with two different models. The thermal stability, determined by thermogravimetric analysis, indicated that PBTDMABQ decomposed above 345°C. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1261–1265, 2005
Development of novel functional conducting elastomer blends containing butyl rubber and low‐density polyethylene for current switching, temperature sensor, and EMI shielding effectiveness applications
Authors: El‐Tantawy Farid
Published: May 2005

A new class of functional conductive butyl rubber (IIR) with different loadings of low‐density polyethylene (PE) was prepared by roll mixing in a milling at a rotor speed of 24 rpm. To understand the filler dispersion and filler/matrix interaction, the network structure of the specimens was examined by evaluating of the crosslinking density, volume fraction of elastomer, interparticle distance among conductive phases, interfacial area per unit volume, torque rheometer, hardness, tensile strength, elongation at break, X‐ray, glass transition temperature, thermal gravemetry, differential scanning calorimetry, degree of crystallinity, and SEM microanalysis. Static conductivity, mobility carrier's concentration, number of charge carriers, and thermoelectric power as a function of PE content were investigated. The temperature dependence of the electrical conductivity as well as the conduction mechanism of IIR–PE blends were also analyzed. The isothermal resistance stability test was examined by displaying the resistance–time curve at certain temperatures. The relationship between current and DC applied voltage was measured for all samples. The self‐electrical heater with PE content of 10 wt % exhibited the highest nonlinearity. The thermal stability was tested by means of temperature–time curve at certain applied power, on and off, for two cycles. Dielectric constant and relative loss factor of the blends are reported. The applicability of the rubber system for switching current, temperature sensor, and electromagnetic shielding effectiveness (EMI) was examined. The experimental results of EMI were compared with theoretical predictions. The results of the present study indicate that these blends are suitable for switching current, temperature‐sensitive sensor, and EMI shielding effectiveness applications with good thermal stability for consumer products. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1125–1138, 2005
New methods for acylation of pure and sawdust‐extracted cellulose by fatty acid derivatives—Thermal and mechanical analyses of cellulose‐based plastic films
Authors: Joly Nicolas , Granet Robert , Branland Pierre , Verneuil Bernard , Krausz Pierre
Published: May 2005

This work deals with the synthesis of cellulosic plastic films obtained in homogeneous conditions by microwave‐induced acylation of commercial or chestnut tree sawdust cellulose by fatty acids. The acylation reaction was studied according to N,N‐dimethyl‐4‐aminopyridine (DMAP) amount, DMAP simultaneously playing the role of catalyst and proton trapping base. This study clearly showed that DMAP does not influence degrees of substitution (DS), massic, and molar yields. Plastic films synthesized in the absence of DMAP showed a decrease in mechanical behavior. Organic (tributylamine) or inorganic bases (CaCO3, Na2CO3) were then added to replace DMAP basic activity, and no changes were observed. Concerning thermal and mechanical properties of plastics obtained with various bases, glass transition temperatures (Tg) and degradation temperature (Td) were found constant whatever the base, and the best mechanical properties were obtained for films synthesized in the presence of CaCO3. The same remarks were made concerning the valorization of chestnut tree sawdust cellulose. Microbial biodegradation of plastic films with DS = 2.2 led to a loss of their mechanical behaviors. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1266–1278, 2005
Effects of nano calcium carbonate modified by a lanthanum compound on the properties of polypropylene
Authors: Guo Tao , Wang Lianshi , Zhang Anqiang , Cai Tongmin
Published: May 2005

The surface modification of nano calcium carbonate (nCaCO3) particles was carried out with a soluble compound of lanthanum via a coating process of chemical deposition, and nCaCO3 particles covered with a compound of lanthanum (nCaCO3La) were prepared. The polypropylene (PP)/nCaCO3 and PP/nCaCO3La composites were prepared with a two‐roll mill. The measurements of the mechanical properties showed that the impact strength of the composites increased at first and then decreased with the addition of fillers, and the tensile strength was reduced at the same time. The impact strength of PP/nCaCO3La was higher than that of PP/nCaCO3, and the impact strength of PP/nCaCO35La was three times that of virgin PP. Transmission electron microscopy and scanning electron microscopy showed that nCaCO3La dispersed well in the PP matrix, the size distribution of the particles was uniform, and nCaCO3La adhered to the PP matrix very closely. The crystallization properties of virgin PP and its composites were studied with differential scanning calorimetry and wide‐angle X‐ray diffraction. The results showed that the β‐PP phase easily formed with the addition of the lanthanum compound. In comparison with virgin PP, the addition of nCaCO3La led to a higher crystallization temperature. The size of the crystallites increased with the addition of nCaCO3La, and the nucleation of PP crystalline was also improved. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1154–1160, 2005
Polymerization of a hydantoinylsiloxane on particles of silicon dioxide to produce a biocidal sand
Authors: Liang J. , Wu R. , Huang T. S. , Worley S. D.
Published: May 2005

The monomer 3‐triethoxysilylpropyl‐5,5‐dimethylhydantoin has been polymerized on the surfaces of sand particles to produce an adhered film that, upon chlorination with dilute sodium hypochlorite bleach, becomes biocidal. The biocidal efficacy of this coated sand has been demonstrated in a cartridge filter experiment against the bacterial pathogens Staphylococcus aureus and Escherichia coli. Complete inactivation was observed within 1 min of contact for the former bacterium and in the interval of 1–5 min for the latter. Upon a loss of biocidal activity due to the depletion of bound chlorine, the coated sand particles can be recharged by further exposure to dilute bleach. Synthetic methods and test data are presented. Potential uses of biocidal sand include disinfection and odor control in water treatment facilities and recirculating baths. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1161–1166, 2005
Effect of solvent on morphology of electrospinning ethyl cellulose fibers
Authors: Wu Xiaohui , Wang Linge , Yu Hui , Huang Yong
Published: May 2005

The influence of the composition of a multicomponent solvent on the surface morphology and diameter distribution of ethyl cellulose fibers produced by electrospinning technology was investigated. The results showed that the average diameter of the fibers using the multicomponent solvent was thinner than when using either of the two components and the diameter distribution of the fibers became narrower. Tiny tubercles formed on the fiber surface, which may improve the specific surface area and broaden the applications. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1292–1297, 2005
Amphiphilic cycloterpolymers of diallyldimethylammonium chloride, diallyloctadecylammonium chloride, and sulfur dioxide
Authors: Ali Sk. Asrof , Umar Yunusa , Abu‐Sharkh B. F.
Published: May 2005

A hydrophilic monomer (diallyldimethylammonium chloride), a hydrophobic monomer (diallyloctadecylammonium chloride), and sulfur dioxide are cycloterpolymerized in dimethylsulfoxide using azobisisobutyronitrile as the initiator to afford water‐soluble cationic polyelectrolytes having a five‐membered cyclic structure on the polymeric backbone. The molecular weights of the polymers containing varying amounts of the hydrophobic monomer (0–7.5 mol %) are determined by light‐scattering experiments. The solution properties of the series of cationic polyelectrolytes are investigated by viscometric techniques. A polymer concentration (C*HA) of <1 g/dL is required for the manifestation of hydrophobic associations in these terpolymers containing C18 hydrophobic pendents. This is a notable improvement over the C*HA values (ca. 15–17 g/dL) for the associating cyclopolymers having a pendant length of C10 to C14. The polymer solutions exhibit a sharp increase in viscosity with increasing polymer concentrations in salt‐free as well as salt‐added solutions. The presence of sodium chloride is shown to enhance the hydrophobic association tremendously. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1298–1306, 2005
Synthesis and properties of soluble polypyrrole doped with dodecylbenzenesulfonate and combined with polymeric additive poly(ethylene glycol)
Authors: Lim H. K. , Lee S. O. , Song K. J. , Kim S. G. , Kim K. H.
Published: May 2005

Soluble polypyrrole (PPy) samples advanced in electrical conductivity σ were chemically synthesized with dodecylbenzenesulfonate (DBS) sodium salt as a dopant, with poly(ethylene glycol) (PEG) as an additive, and with ammonium persulfate as an oxidant. The PPy–DBS–PEG samples were soluble in organic solvents (N‐methylpyrrolinone and m‐cresol). The greater the molar percentage ratio was of DBS, the greater the solubility was of synthesized PPy composites (PPy–DBS–PEG). The maximum electrical conductivity at room temperature for PPy–DBS–PEG was 1.02 S/cm, which was in fact the true conductivity of 100/10 (mol %) PPy/DBS. The chemical composition and doping level of PPy–DBS–PEG were determined by elemental analysis. The results of Fourier transform infrared spectroscopy were used for the structural characterization of PPy–DBS–PEG. The scanning electron microscopy results showed that the electrical conductivity was related to the morphology of PPy–DBS–PEG. According to thermogravimetric analysis, PPy–DBS–PEG was more thermostable than PPy–DBS. Electron spin resonance measurements showed that the polaron and bipolaron acted as charge carriers of PPy–DBS–PEG. According to the temperature dependence of the electrical conductivity, PPy–DBS–PEG was a semiconductor and followed the three‐dimensional variable‐range hopping model. The improved electrical conductivity apparently resulted from the reduction of the crosslinking and structural defects of the PPy chains. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1170–1175, 2005
Polyurethane and carboxylated polysulfone blend ultrafiltration membranes. I. Preparation and characterization
Authors: Latha C. S. , Shanthanalakshmi D. , Mohan D. , Balu K. , Kumarasamy M. D. K.
Published: May 2005

Polysulfone was functionalized by carboxylation and blended with polyurethane (ether type). Blend membranes were prepared in the presence and absence of the additive poly(ethylene glycol) 600 and subjected to ultrafiltration characterizations such as compaction, pure water flux, water content, and hydraulic resistance. Morphological studies of the membranes were performed with scanning electron microscopy. The effects of the polymer composition and additive concentrations on the above parameters were analyzed and the results compared. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1307–1315, 2005
Properties and preparation of thermoplastic polyurethane/silica hybrid using sol–gel process
Authors: Lai S.‐M. , Wang C.‐K. , Shen H.‐F.
Published: May 2005

A thermoplastic polyurethane elastomer/silica hybrid (TPU/SiO2) was prepared using the sol–gel process. This work was undertaken to investigate the thermal and physical properties of this type of hybrid by employing different catalyst systems during sol–gel processing. Two types of catalyst systems including acetic acid (HOAc) and hydrochloric acid (HCl) were used to prepare sol particles. The mixing of the sol solution and TPU solution was then carried out to form a TPU/silica hybrid. Fourier transform IR spectra and dynamic mechanical properties were recorded to depict the enhanced interfacial interaction. Thermogravimetric analysis was used to determine the actual silica content forming in the hybrid and to evaluate the heat resistance of the hybrid. Mechanical properties such as the tensile strength and cutting strength were investigated at various concentrations of in situ silica. The tensile strength increased at all concentrations of silica. In contrast, the cutting strength decreased, probably because of a reduction of the energy dissipation from silica as physical crosslinks. The HOAc catalyzed system showed better optical properties than the HCl catalyzed system. The fracture surface was revealed through scanning electron microscopy to observe the degree of dispersion of SiO2, which in turn confirmed the results for the optical and mechanical properties. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1316–1325, 2005