bluuebunny/crossref_metadata_2025_split huggingface dataset:
Toughening of Polystyrene with Ethylene‐Propylene‐Diene Terpolymer (EPDM) Compatibilized by Styrene‐Butadiene‐Styrene Block Copolymer (SBS)
Authors: Fang Zhengping , Guo Zhenghong , Zha Linlin 
Published: August 2004

AbstractSummary: Polystyrene (PS) was toughened with ethylene‐propylene‐diene terpolymer (EPDM) in the presence of styrene‐butadiene‐styrene block copolymer (SBS). Incorporation of SBS into the PS/EPDM blends clearly improved the impact properties. For PS/EPDM/SBS (mass ratio: 69/21/10) blends, the notched Charpy impact strength reached a maximum value of 26.3 kJ/m2. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) showed that SBS was distributed on the interface between PS and EPDM. Butanone extraction and FTIR analysis found that there was a grafting reaction between PS and EPDM phase during melt compounding. Shearing and processing rheological behaviors of blends were evaluated with a Haake capillary rheometer and a torque rheometer, respectively.
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Poly(acrylonitrile‐butadiene‐styrene)/Poly(ether ether ketone) Blends: an Attempt Towards a Polymer Reinforced Polymer Composite
Authors: Nandan Bhanu , Kandpal Laxmi D. , Mathur Gyanesh N. 
Published: August 2004

AbstractSummary: Blends of poly(acrylonitrile‐butadiene‐styrene) (ABS) and poly(ether ether ketone) (PEEK), in which PEEK has been used as a reinforcing medium for the ABS matrix in ratios up to 20 wt.‐% of the blend, were prepared by melt mixing using a laboratory mixer. All the blend compositions were processed at the ABS processing temperature so that the PEEK was dispersed in the ABS matrix without actually melting. Differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA) studies revealed that the glass transition temperature (Tg) of the ABS phase in the blend did not show any appreciable change with composition. The dynamic storage modulus measured by DMA was found to be higher for the blend as compared to pure ABS due to reinforcement of the matrix by PEEK. The tensile strength and modulus behavior of these blends were found to follow the curves predicted using models proposed for composite systems having perfect adhesion, which shows the presence of some physical interaction between the blend components. The good tensile properties of the blend have been correlated with the observed morphology. The disperse phase in the blend has been found to be present in extremely small (sub‐micron) dimensions, which not only provides more surface area for possible interactions between the blend components but also result in efficient stress transfer between the matrix and the dispersed phase during the tensile tests. The thermal stability of the blends was investigated using thermogravimetric analysis (TGA). TGA further revealed that the constituents degraded at their respective decomposition temperatures.SEM micrograph of tensile fractured surface of an ABS/PEEK 90/10 blend.magnified imageSEM micrograph of tensile fractured surface of an ABS/PEEK 90/10 blend.
Hypoelliptic systems connected with Newton's polyhedron
Authors: Bouzar Chikh , Volevich Leonid 
Published: August 2004

AbstractWe introduce a general class of hypoelliptic systems of partial differential operators with variable coefficients generalizing the so‐called multi‐quasi‐elliptic differential operators. We study the regularity of solutions of these systems. More complete results are obtained in the case of two independent variables. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Atomic decomposition for the vorticity of a viscous flow in the whole space
Authors: Brandolese Lorenzo 
Published: August 2004

AbstractWe show that the vorticity of a viscous flow in ℝ3 admits an atomic decomposition of the form ω(x, t) = $ \textstyle \sum ^\infty _{k = 1} $ ωk(x – xk, t), with localized and oscillating building blocks ωk, if such a property is satisfied at the beginning of the evolution. We also study the long time behavior of an isolated coherent structure and the special behavior of flows with highly oscillating vorticities. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Local growth envelopes of spaces of generalized smoothness: the subcriticalcase
Authors: Caetano António M. , Moura Susana D. 
Published: August 2004

AbstractThe concept of local growth envelope (ℰLGA, u) of the quasi‐normed function space A is applied to the spaces of generalized smoothness B(s,ψ) pq (ℝn) and F(s,ψ)pq (ℝn) and it is shown that the influence of the function ψ, which is a fine tuning of the main smoothness parameter s, is strong enough in order to show up in the corresponding growth envelopes. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Leprosy and the peripheral nervous system: Basic and clinical aspects
Authors: Ooi Winnie W. , Srinivasan Jayashri 
Published: August 2004

AbstractLeprosy is one of the most common causes of nontraumatic peripheral neuropathy in the developing world. The causative agent,Mycobacterium leprae, has a predilection for Schwann cells, where the organism multiplies unimpeded by organism‐specific host immunity, resulting in destruction of myelin, secondary inflammatory changes, and destruction of the nerve architecture. The cardinal diagnostic features of leprosy are anesthetic skin lesions, neuropathy, and positive skin smears for the bacilli. However, patients may rarely present without skin lesions in pure neuritic leprosy. Electrodiagnostic findings early in the disease reveal demyelinating features, such as slowing of conduction velocity and prolongation of latencies, but as the disease progresses secondary axonal damage commonly ensues. Electrodiagnostic studies are also useful to monitor for toxicity secondary to therapy, particularly thalidomide‐associated neuropathy. Nerve biopsy of a sensory cutaneous nerve is sometimes essential to confirm a diagnosis of leprosy. Significant advances in understanding of the pathogenesis, mapping of the genome, and other advances in molecular biology may result in better preventive and therapeutic modalities, and the goal of eradicating leprosy as a global problem may yet be realized. Muscle Nerve 30: 393–409, 2004
ParCYCLIC: finite element modelling of earthquake liquefaction response on parallel computers
Authors: Peng Jun , Lu Jinchi , Law Kincho H. , Elgamal Ahmed 
Published: August 2004

AbstractThis paper presents the computational procedures and solution strategy employed in ParCYCLIC, a parallel non‐linear finite element program developed based on an existing serial code CYCLIC for the analysis of cyclic seismically‐induced liquefaction problems. In ParCYCLIC, finite elements are employed within an incremental plasticity, coupled solid–fluid formulation. A constitutive model developed for simulating liquefaction‐induced deformations is a main component of this analysis framework. The elements of the computational strategy, designed for distributed‐memory message‐passing parallel computer systems, include: (a) an automatic domain decomposer to partition the finite element mesh; (b) nodal ordering strategies to minimize storage space for the matrix coefficients; (c) an efficient scheme for the allocation of sparse matrix coefficients among the processors; and (d) a parallel sparse direct solver. Application of ParCYCLIC to simulate 3‐D geotechnical experimental models is demonstrated. The computational results show excellent parallel performance and scalability of ParCYCLIC on parallel computers with a large number of processors. Copyright © 2004 John Wiley & Sons, Ltd.
Stresses due to vertical subsurface loading for an inhomogeneous cross‐anisotropic half‐space
Authors: Wang Cheng‐Der , Pan Ernian 
Published: August 2004

AbstractIn this article, we present the solutions for the stresses induced by four different loads associated with an axially loaded pile in a continuously inhomogeneous cross‐anisotropic half‐space. The planes of cross‐anisotropy are parallel to the horizontal surface of the half‐space, and the Young's and shear moduli are assumed to vary exponentially with depth. The four loading types are: an embedded point load for an end‐bearing pile, uniform skin friction, linear variation of skin friction, and non‐linear parabolic variation of skin friction for a friction pile. The solutions for the stresses due to the pile load are expressed in terms of the Hankel integral and are obtained from the point load solutions of the same inhomogeneous cross‐anisotropic half‐space which were derived recently by the authors (Int. J. Rock Mech. Min. Sci. 2003; 40(5):667–685). A numerical procedure is proposed to carry out the integral. For the special case of homogeneous isotropic and cross‐anisotropic half‐space, the stresses predicted by the numerical procedure agree well with the solutions of Geddes and Wang (Geotechnique 1966; 16(3):231–255; Soils Found. 2003; 43(5):41–52). An illustrative example is also given to investigate the effect of soil inhomogeneity, the type and degree of soil anisotropy, and the four different loading types on the vertical normal stress. The presented solutions are more realistic in simulating the actual stratum of loading problem in many areas of engineering practice. Copyright © 2004 John Wiley & Sons, Ltd.
Tensile properties and creep response of polypropylene fibre composites with variation of fibre diameter
Authors: Houshyar S , Shanks RA 
Published: August 2004

AbstractThe mechanical properties and morphology of polypropylene (PP) long‐fibre reinforced random poly(propylene‐co‐ethylene) (PPE) composites (50/50 % vol/vol) have been investigated with reference to the fibre diameter with constant length. There is an improvement in the mechanical properties of PPE matrix by incorporation of long PP fibres into the matrix. The elastic modulus of the composite increased with decrease in the fibre diameter to 50 µm, to 0.91 GPa, which was 5 times higher than for pure PPE. However, composite stiffness decreased with decreasing fibre diameter of less than 50 µm and this is discussed in term of the fibre stiffness, packing, stress concentration and aspect ratio. Creep resistance of the composites showed the same behaviour. Morphology of the composites was investigated using scanning electron microscopy. This showed that there was a thin layer of matrix on the reinforcement, which was attributed to good impregnation and wetting of the fibres. Moreover, prediction of tensile modulus using the Cox model correlated well with experimental data. Copyright © 2004 Society of Chemical Industry
Exciton–phonon interaction and Raman spectra of [(CH3)2NH2]5Cd2CuCl11 crystals
Authors: Kapustianik V. , Batiuk A. , Czapla Z. , Podsiadła D. , Czupiński O. , Eliyachevskyy Yu. , Rudyk V. 
Published: August 2004

AbstractTemperature evolution of the exciton–phonon interaction (EPI) in ((CH3)2NH2)5Cd2CuCl11 solid solution was studied on the basis of absorption spectroscopy data. The obtained values of effective phonon energies were compared with the data of Raman spectroscopy. It is shown that the (T) and E′ parameters of Urbach's rule show the continuous anomalous change characteristic of the second‐order phase transition at T1 = 176 K. The anomalous behaviour of the EPI and other spectral parameters at T0 = 310–315 K was related to the complex co‐operative effect involving weakening of the hydrogen bonds and variation of the Jahn–Teller distortion of metal–halogen polyhedra with temperature. This process takes place only within the copper–chlorine sublattice and due to this would be hardly related to the usual phase transition. At the same time, the considered temperature change of the tetragonal distortion of the metal–halogen octahedra is followed by nonfulfillment of Urbach's rule in the temperature range T T0. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electronic and structural properties of strontium chalcogenides SrS, SrSe and SrTe
Authors: Rached D. , Rabah M. , Benkhettou N. , Soudini B. , Abid H. 
Published: August 2004

AbstractWe present the results of a first‐principles study of the electronic and structural properties of strontium chalcogenides, SrS, SrSe and SrTe. The computational method is based on the full‐potential linear muffin‐tin orbitals method (FP‐LMTO) augmented by a plane‐wave basis (PLW). The exchange and correlation energy is described in the local density approximation (LDA) using the Perdew–Wang parameterization including a generalized gradient approximation (GGA). The calculated results of the structural properties are given for the NaCl (B1) and CsCl (B2) structures. We have also carried out band‐structure calculations for the three considered compound, but only for the NaCl (B1) structure. A reasonable agreement is found from the comparison of our results with other theoretical calculations and experimental data. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Basal stacking faults and (10&1macr;2) twin energies by a semi‐empirical tight‐binding method for zinc and cadmium
Authors: Béré A. , Chen J. , Hairie A. , Nouet G. , Paumier E. 
Published: August 2004

AbstractThe study of extended defects requires atomic modelisation able to give theoretical values characterizing the defects to be compared to experimental observations. In the case of zinc and cadmium which are hexagonal metals with high c/a ratio, such a comparison is still controversial due to the difficulty of using known potentials. A previously developed semi‐empirical tight‐binding method is now applied to calculate the energy of extended defects in Zn and Cd. A good correlation is obtained for hypothetical polytypes and for basal stacking faults. For the (10&1macr;2) twin, two possible interfaces are found and discussed with respect to the experimental results. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Oxygen transmission rates of packages at ambient, chill and freezing temperatures measured by the AOIR method
Authors: Larsen Hanne 
Published: August 2004

AbstractThe ambient oxygen ingress rate (AOIR) method is an alternative or supplementary method to Ox‐Tran for measuring the oxygen transmission rate (OTR) of packages. The method has high capacity, requires relatively inexpensive equipment and measures OTR at different temperatures and humidity conditions. The aim of this study was, on the one hand, to study the effect of temperature on the OTR for packages produced from different polymer materials and laminates, and on the other hand to evaluate the suitability of the AOIR method at freezing temperature conditions. The OTR for 10 packages with different polymer compositions was measured at 23°C, 6°C and −25°C. The AOIR method was shown to be a reliable test method for measuring OTR of packages at all the applied test conditions, also at frozen storage temperature. The OTR for the packages decreased with lower temperatures, especially for the packages with the highest OTR values at 23°C. In order to avoid higher packaging expenses than necessary to obtain the required shelf‐life for different food products, the OTR for alternative packages should be measured at the temperature and humidity conditions of intended use. Copyright © 2004 John Wiley & Sons, Ltd.
Assessment of oxygen levels in convenience‐style muscle‐based sous vide products through optical means and impact on shelf‐life stability
Authors: O'Mahony Fiach C. , O'Riordan Tomás C. , Papkovskaia Natalia , Ogurtsov Vladimir I. , Kerry Joe P. , Papkovsky Dmitri B. 
Published: August 2004

AbstractAn optical oxygen analyser was used in two small‐scale industrial trials to non‐destructively assess the quality of packaged convenience foods and packaging process. Beef lasagne packed under 70% vacuum and cooked under standard sous vide conditions was monitored for residual oxygen, using disposable sensors incorporated in each pack and a benchtop optical oxygen analyser. High levels of residual oxygen close to ambient were determined in the majority of packs after packaging, as opposed to anticipated levels of 4–5%. Residual oxygen was monitored over product shelf‐life (4 weeks at +4–10°C) along with measurement of microbial growth and lipid oxidation in food by conventional destructive methods. Oxygen levels in packs went down to almost zero between weeks 2 and 3 indicating deterioration of packaged product. Correlation between oxygen profiles and the rate of microbial growth and lipid oxidation was established. The optical oxygen sensor system was shown to provide valuable information about performance of the packaging process, product storage conditions and food quality in a convenient and cost‐efficient fashion and non‐destructively. Copyright © 2004 John Wiley & Sons, Ltd.
Heat penetration characteristics and shelf‐life studies of mushrooms in brine processed in retort pouches
Authors: Chandrasekar V. , Gopal T. K. Srinivasa , Rai R. D. 
Published: August 2004

AbstractWhite button mushrooms were washed, blanched and cut longitudinally into two halves. 100 g mushroom halves was placed into each retort pouch and 90 ml hot brine (2% salt, 0.1% citric acid) was added. Retort pouches (105 µm thick) had an outer polyester layer (12.5 µm), a middle aluminium layer (12.5 µm) and an inner cast polypropylene layer (80 µm); pouch size was 20 × 16 cm, seal size 10 mm and lip size 4 mm. Pouches were fixed with thermocouples for recording the core temperature of the mushroom pieces, using a data recorder and a computer. After sealing and over‐pressure retorting at F0 = 9.6, the pouches were stored at the ambient conditions. The heat penetration parameters were calculated. The heating curve obtained was logarithmic in nature. Sensory evaluation of mushroom curry prepared from the stored mushrooms showed that the product had high acceptability (7.9 on a scale of 10) which reduced very slightly (to 7.5) during storage for 12 months. No deformity, leakage or spoilage was noticed and the product remained sterile and acceptable even after 12 months of storage at the ambient conditions (20–30°C). Copyright © 2004 John Wiley & Sons, Ltd.
A design database for moulded pulp packaging structure
Authors: Ma X. , Soh A.K. , Wang B. 
Published: August 2004

AbstractIn this study, a structural factor approach is developed to allow a modular design method be used for the packaging design of thin‐walled structures. Numerical simulations of the structural units are carried out to evaluate the influence of the structural factors under static loading, by using the commercial finite element code ABAQUS/Explicit. Empirical relations between the load‐bearing capacity of structural units and structural factors are established based on numerical simulations. A database is then constructed that has the ability to provide valuable information for the loading performances of different structural units. Copyright © 2004 John Wiley & Sons, Ltd.
Dynamic, open inquiry in biology learning
Authors: Zion M. , Slezak M. , Shapira D. , Link E. , Bashan N. , Brumer M. , Orian T. , Nussinowitz R. , Court D. , Agrest B. , Mendelovici R. , Valanides N. 
Published: August 2004

AbstractIn the new biology‐learning curriculum for Israeli high schools, known as Biomind, students experience “open‐inquiry.'' This paper describes a qualitative action research project that was performed in order to investigate the characteristics of the open inquiry learning process. Specifically, the research investigates this process in terms of the concepts of evidence, affective aspects, and other aspects that may emerge by following the open inquiry process. This paper also discusses how the findings from the open inquiry process can be used for further curriculum improvement.This research characterized the open inquiry as a dynamic inquiry learning process. The main criteria for characterizing the dynamic inquiry are learning as a process, changes occurring during the research, procedural understanding, and affective points of view. The paper further suggests methods of documenting the dynamic inquiry process. This documentation can assist in understanding the inquiry process from both the cognitive and metacognitive points of view. The educational and research processes described here contributed both to improving the curriculum and to establishing an infrastructure through which the science education community can emphasize dynamic aspects of science in open inquiry learning. © 2004 Wiley Periodicals, Inc. Sci Ed. 88:728–753, 2004
A framework for capturing the relationship between usability and software architecture
Authors: Folmer Eelke , van Gurp Jilles , Bosch Jan 
Published: August 2004

AbstractUsability is increasingly recognized as an essential factor that determines the success of software systems. Practice shows that for current software systems, most usability issues are detected during testing and deployment. Fixing usability issues during this late stage of the development proves to be very costly. Some usability‐improving modifications such as usability patterns may have architectural implications. We believe that the software architecture may restrict usability. The high costs associated with fixing usability issues during late‐stage development prevent developers from making the necessary adjustments for meeting all the usability requirements. To improve upon this situation, we have investigated the relationship between usability and software architecture to gain a better understanding of how the architecture restricts the level of usability. Our article makes a number of contributions; a framework is presented that expresses the relationship between usability and software architecture. The framework consists of an integrated set of design solutions such as usability patterns and usability properties that have been identified in various cases in industry, modern day software and literature surveys. These solutions, in most cases, have a positive effect on usability but are difficult to retrofit into applications because they have architectural impact. Our framework may be used to guide and inform the architectural design phase. This may decrease development costs by reducing the amount of usability issues that need to be fixed during the later stages of development. Copyright © 2004 John Wiley & Sons, Ltd.
Separation in theory, coordination in practice – teaching HCI and SE
Authors: Clemmensen Torkil , Nørbjerg Jacob 
Published: August 2004

AbstractThe lack of shared perspective, techniques and notations between the disciplines of Software Engineering and Human–Computer Interaction creates challenges for practice as well as teaching in information systems development. In this article, we argue that the ‘gaps’ between the two disciplines are caused not only by different language and concepts but also by differences in the disciplines' basic assumptions, goals and theories. Reconciling these differences through common notations, techniques or life cycles will therefore require considerable effort and provide only dubious benefits. Instead we propose, using our own teaching as an example, that a reasonable way forward is to teach the two disciplines as separate subjects while at the same time emphasizing their mutual dependencies and meeting points in practical systems development—in theory as well as in practice. Results from applying this approach during a second‐year undergraduate program are presented, and ideas for further separation and coordination of HCI/SE in university‐level courses are discussed. Copyright © 2004 John Wiley & Sons, Ltd.