19 research outputs found

    Az adverbiumok mondattani és jelentéstani kérdései = The syntax and syntax-semantics interface of adverbial modification

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    A határozószók és a határozók alaktani, mondattani és funkcionális kérdéseit vizsgáltuk a generatív nyelvelmélet keretében, főként magyar anyag alapján. Olyan leírásra törekedtünk, melyből a különféle határozófajták mondattani viselkedése, hatóköre, valamint hangsúlyozása egyaránt következik. A különféle határozótípusok PP-ként való elemzésének lehetőségét bizonyítottuk. A határozók mondatbeli elhelyezése tekintetében a specifikálói pozíció (Cinque 1999) ellen és az adjunkciós elemzés (Ernst 2002) mellett érveltünk. Megmutattuk, hogy a határozók szórendjének levezetéséhez bal- és jobboldali adjunkció feltételezése egyaránt szükséges. A különféle határozófajták szórendi helyét mondattani, jelentéstani és prozódiai tényezők összjátékával magyaráztuk. A jelentéstani tényezők között pl. a határozók inkorporálhatóságát korlátozó típusmegszorítást, a negatív határozók kötelező fókuszálását előidéző skaláris megszorítást, egyes határozófajták és igefajták komplex eseményszerkezetének inkompatibilitását vizsgáltuk. Az ige mögötti határozók szórendjét befolyásoló prozódiai tényező például a növekvő összetevők törvénye. Megfigyeltük az intonációskifejezés- újraelemzés kiváltódásának feltételeit és jelentéstani következményeit is. A helyhatározói igekötők egy típusát a mozgatási láncok sajátos fonológiai megvalósulásaként (a fonológiailag redukált kópia inkorporációjaként) elemeztük. A tárgykörben mintegy 60 tanulmányt publikáltunk. Adverbs and Adverbial Adjuncts at the Interfaces (489 old.) c. könyvünket kiadja a Mouton de Gruyter (Berlin). | This project has aimed to clarify (on the basis of mainly Hungarian data) basic issues concerning the category "adverb", the function "adverbial", and the grammar of adverbial modification. We have argued for the PP analysis of adverbials, and have claimed that they enter the derivation via left- and right-adjunction. Their merge-in position is determined by the interplay of syntactic, semantic, and prosodic factors. The semantically motivated constraints discussed also include a type restriction affecting adverbials semantically incorporated into the verbal predicate, an obligatory focus position for scalar adverbs representing negative values of bidirectional scales, cooccurrence restrictions between verbs and adverbials involving incompatible subevents, etc. The order and interpretation of adverbials in the postverbal domain is shown to be affected by such phonologically motivated constraints as the Law of Growing Constituents, and by intonation-phrase restructuring. The shape of the light-headed chain arising in the course of locative PP incorporation is determined by morpho-phonological requirements. The types of adverbs and adverbials analyzed include locatives, temporals, comitatives, epistemic adverbs, adverbs of degree, manner, counting, and frequency, quantificational adverbs, and adverbial participles. We have published about 60 studies; our book Adverbs and Adverbial Adjuncts at the Interfaces (pp. 489) is published in the series Interface Explorations of Mouton de Gruyter, Berlin

    Deformation and failure of sugarcane bagasse reinforced PP

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    Polypropylene composites were prepared from sugarcane bagasse fibers by extrusion and injection molding. Wood flour was used as reference filler in the study. The fiber content of the composites changed between 0 and 30 wt% in 5 wt% steps. Maleated polypropylene was used as coupling agent to improve interfacial adhesion. Mechanical properties were characterized by tensile and fracture testing, while local deformation processes were followed by acoustic emission and instrumented impact testing, as well as by the analysis of scanning electron micrographs. The results showed that sugarcane bagasse fibers reinforce polypropylene similarly to other natural fibers. They increases stiffness, but decrease tensile yield stress, tensile strength and deformability. Increased interfacial adhesion leads to the considerable improvement of reinforcement. Bagasse fiber and wood flour filled composites have very similar properties. The impact resistance of the composites increased in the presence of both fibers compared to the neat matrix. Debonding is the dominating process in the absence of the coupling agent, while mainly fiber fracture occurs in its presence. Increased plastic deformation after debonding results in slightly improved impact resistance

    DEFORMATION AND FAILURE BEHAVIOUR OF SUGARCANE BAGASSE REINFORCED PP

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    Polypropylene composites were prepared from sugarcane bagasse fibers by extrusion and injection molding. Wood flour was used as reference filler in the study. The fiber content of the composites changed between 0 and 30 wt% in 5 wt% steps. A maleated polypropylene was used as coupling agent to improve interfacial adhesion. Mechanical properties were characterized by tensile and fracture testing, while local deformation processes were followed by acoustic emission and instrumented impact testing as well as by the analysis of scanning electron micrographs. The results showed that sugarcane bagasse fibers reinforce polypropylene similarly to other natural fibers. They increases stiffness, but decreases tensile yield stress, tensile strength and deformability. Increased interfacial adhesion leads to the considerable improvement of reinforcement. Bagasse fiber and wood flour filled composites have very similar properties. The impact resistance of the composites increased in the presence of both fibers compared to the neat matrix. Debonding is the dominating process in the absence of the coupling agent, while mainly fiber fracture occurs in its presence. Increased plastic deformation after debonding results in slightly improved impact resistance

    Reinforcement of polypropylene with alkali-treated sugarcane bagasse fibers: Mechanism and consequences

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    Polypropylene composites were prepared from neat and alkali-treated sugarcane bagasse fibers. The results showed that alkali treatment leads to an increase in composite stiffness and strength. A maximum is achieved in these properties at around 5 wt% NaOH content of the treating solution. The increase in properties was assigned to the improvement in inherent fiber characteristics. Acoustic emission testing and electron microscopy showed that the two main local deformation processes related to the fibers are their fracture and debonding; the latter is accompanied by the shear yielding of the matrix. Increased inherent strength of the fibers results in an increase in the fracture initiation stress and fracture energy of the composites. Interfacial adhesion has a slight effect on stiffness, but more significant on strength and impact resistance. Changing adhesion modifies the relative importance of local deformation processes, the number of debonding events decreases, while fiber fracture increases with increasing adhesion. Increased interfacial adhesion improves stress transfer and the load bearing capacity of the fibers as well, but suppresses matrix yielding. Alkali treatment increases inherent fiber strength, which can be directly correlated with composite strength

    Alkali treatment of lignocellulosic fibers extracted from sugarcane bagasse: Composition, structure, properties

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    Lignocellulosic fibers extracted from sugarcane bagasse were treated with NaOH solutions of different concentration (0-40 wt%) to study the effect of alkali treatment on the composition, structure and properties of the fibers. Composition was determined by the van Soest method, structure was characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM), while mechanical properties by tensile testing. Hemicellulose and lignin content decrease, while cellulose content goes through a maximum as a function of alkali concentration. Crystallinity changes only slightly and microfibril angle (MFA) remains constant thus structural effects and especially MFA are not the primary reasons for changing properties. The Youngs modulus of the fibers shows a slight maximum at around 2-4 wt% NaOH content, while tensile strength goes through a much more pronounced one at around 5-8 wt%. Direct correlation between structure and mechanical properties was not found indicating that composition is more important in the determination of properties than structure. Regression analysis proved that the combination of several compositional variables determines mechanical properties in a non-linear manner. The improvement in fiber properties was explained with the dissolution of weak amorphous fractions and the relative increase of cellulose content

    Alkali treatment of lignocellulosic fibers extracted from sugarcane bagasse: Composition, structure, properties

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    This work reported the study on the effect of alkali treatment using NaOH solutions of different concentration (0-40 wt.%) of sugarcane bagasse fibers on their composition, structure and properties. The results evidenced that treatment modifies the composition, structure and properties of the fibers. The content of hemicellulose and lignin reduce, while cellulose content turns through a maximum as a function of NaOH concentration. A small change in crystallinity was identified and microfibril angle (MFA) remained constant thus structural effects and especially MFA were not the main reasons for altering the properties. The stiffness of the fibers shows a slight maximum at around 2-4 wt.% NaOH content, while a much more pronounced strength found at around 5-8 wt.%. Direct correlation between structure and mechanical properties was not found, indicating that composition is more essential in the determination of properties than structure. The optimum concentration of the treating solution is around 5 wt% NaOH content, if the time of treatment is fixed at 1 hour

    Deformation and failure of sugarcane bagasse reinforced PP

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    Polypropylene composites were prepared from sugarcane bagasse fibers by extrusion and injection molding. Wood flour was used as reference filler in the study. The fiber content of the composites changed between 0 and 30 wt% in 5 wt% steps. Maleated polypropylene was used as coupling agent to improve interfacial adhesion. Mechanical properties were characterized by tensile and fracture testing, while local deformation processes were followed by acoustic emission and instrumented impact testing, as well as by the analysis of scanning electron micrographs. The results showed that sugarcane bagasse fibers reinforce polypropylene similarly to other natural fibers. They increases stiffness, but decrease tensile yield stress, tensile strength and deformability. Increased interfacial adhesion leads to the considerable improvement of reinforcement. Bagasse fiber and wood flour filled composites have very similar properties. The impact resistance of the composites increased in the presence of both fibers compared to the neat matrix. Debonding is the dominating process in the absence of the coupling agent, while mainly fiber fracture occurs in its presence. Increased plastic deformation after debonding results in slightly improved impact resistance
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