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The development of sub-micro filler enhanced polymer composites
No full textSub-micro silica flakes and graphite reinforced polymer composites have been developed in this research. The sub-micro polymer composites are designed to overcome problems associated with nanocomposite technology. Apart from the high cost of production, the other major problem in nanocomposites is reduced efficiency in mechanical reinforcement at high filler loadings. The surface area of nano-fillers in high filler loaded composites is too high resulting in insufficient polymer molecules to wet the filler surface and hence increased filler agglomeration occurs. Increasing filler dimension into the sub-micro range can avoid such difficulties. The dimension of fillers in the sub-micro range also has the advantage of utilising modern polymer processing technologies.
In this thesis, sub-micro composite reinforcement has been studied through the identification of suitable fillers, modelling of sub-micro composites and experimental validation of model predictions. The processing methodology, effects of filler loading, aspect ratio and compatibility of filler with matrix are also investigated. In addition, rheology, crystallisation, fracture toughness and the thermodynamic behaviour of submicro filler reinforced polymer composites are studied. The investigation was primarily focused on various combinations of single-layered silica flakes and multi-layered graphite sheets reinforced nylon-6 and polypropylene. The predicted Young's modulus and strengths of developed composites are as high as 3.3 GPa and 81 MPa at 5wt% silica flake content as well as 11.75 GPa and 301MPa at 30wt% flake fraction, respectively. Experimental results show that tensile modulus and strengths of the submicro composites produced agree well with modelling data at low filler loading. They are, however, much lower than the predictions in the high filler loading range due to the breakage of silica flakes during composite processing. In spite of filler breakage, the tensile modulus and strength of 5wt% silica flake reinforced N6 improved 68% and 67% respectively, compared to the N6. The tensile strength is also 38% higher than thatof 5wt% clay/N6 nanocomposites. The tensile modulus of 30wt% silica flake reinforced N6 improved over 240% which is similar to the achievement of 30wt% glass fibre/N6 composites. In addition, the fracture toughness and thermal deflection temperature of a silica flake/N6 composite improved by 17% at 5wt% and 20.3 oC at 10wt% filler content respectively.
For multi-layered graphite sheet reinforced polypropylene sub-micro composites, mechanical properties are a function of both filler thickness and filler loading. Over 112% improvement in Young's modulus has been achieved with a composite produced via a multi-extrusion method at 20wt% filler loading, compared with the pure polymer.
The crystallinities of all sub-micro composites produced are either similar to or lower than those of pure polymers. This implies that the major contribution to the improvement of mechanical properties is from sub-micro fillers. In addition, the crystallisation rate and crystallisation temperature of sub-micro composites are increased when compared with base polymers due to the nucleation effect of fillers. The introduction of sub-micro fillers into nylon-6 and polypropylene did not result in significant change in rheology. This may be associated with flake breakage and relatively poor interfacial bonding at the filler/polymer interface.
In summary, this work demonstrates the potential of sub-micro filler enhanced composites in improving major engineering properties. It also proves that the sub-micro approach can fill the gap between nano and fibre reinforcement
sj-docx-1-tej-10.1177_20417314221125310 – Supplemental material for Expanding tubular microvessels on stiff substrates with endothelial cells and pericytes from the same adult tissue
No full textSupplemental material, sj-docx-1-tej-10.1177_20417314221125310 for Expanding tubular microvessels on stiff substrates with endothelial cells and pericytes from the same adult tissue by Xiuyue Song, Yali Yu, Yu Leng, Lei Ma, Jie Mu, Zihan Wang, Yalan Xu, Hai Zhu, Xuefeng Qiu, Peifeng Li, Jing Li and Dong Wang in Journal of Tissue Engineering</p
Wen hua shi ying dui gan zhi de ying xiang: bian hua gan zhi, xin qi mu biao jian ce he xu huan mo shi shi bie de san fang mian de zheng ju
No full textXu, Yi.Thesis Ph.D. Chinese University of Hong Kong 2015.Includes bibliographical references (leaves 48-54).Abstracts also in Chinese.Title from PDF title page (viewed on 05, January, 2017).Xu, Yi
Data For "Recommending Scientific Datasets Using Author Networks in Ensemble Methods"
No full textData for paper "Recommending Scientific Datasets Using Author Networks in Ensemble Methods" which is accepted by Data Science Journal. These data contains 1)MAKG (Microsoft Academic Knowledge Graph) co-author network (HDT/RDF format), 2)MAKG paper/dataset title collection (HDT/RDF format), 3) MAKG paper/dataset abstract collection (HDT/RDF format)
Vibrationally Excited Level Identification and FIR Laser Line Prediction by the "Ritz" and "LaseRitz" Programs
No full text G. Moruzzi and Li-Hong Xu, Ohio State University 49th International Symposium on Molecular Spectroscopy, TD04, p. 122 (1994).Author Institution: Università di Pisa, Piazza Torricelli 2, I-56100 Pisa, Italy; National Institute of Standards and Technology, Gaithersburg, MD 20899 U.S.A.Following last year's Columbus , we have continued our work on an interactive computer program for automating assignment of the Fourier-Transform methanol spectrum. Two new features have been developed. (1) A new routine has been incorporated in the Ritz program for the identification of small-amplitude vibrationally excited levels starting from the known energies of the ground-vibrational levels. We have been testing this routine in the region for . (2)A new LaseRitz program has been written for predicting FIR laser lines using known energies of the ground and the vibrationally excited levels. The simplified float chart of the interactive program is presented below
Xu Guangqi shi 'Pi wang' de zuo zhe ma?
No full textDeals with the question whether or not Xu Guangqi (1562-1633) is the author of the Christian, anti-Buddhist essay 'Pi wang'status: Publishe
1 Hz dynamical strain waves during the 2011 Tohoku Mw9.0 earthquake from high-rate GNSS
No full textThis set of movie files is generated by this author with the GEONET GPS raw data provided by the Geospatial Information Authority (GSI) of JapanThe movie files uploaded on 2025/02/21 have been updated from GPS time to UTC time. The new files are listed as follows: 「S1F1movieEastComponentStrainsFUTC.avi」「S1F2movieNorthComponentStrainsFUTC.avi」「S1F3movieDilatationsFUTC.avi」「S1F4moviePrincipalStrainsUTC.avi」「S1F5movieMaximumShearFUTC.avi」「S1F6movie2ndMainStrainInvariantsFUTC.avi」.1.
Xu Shen's graphic analysis revisited
No full textInternational audienceLike other writing systems, the Chinese writing is based on a limited number of basic elements. Compared to the 26 letters of the alphabet, or the 70 hiragana and katakana signs for (modern) Japanese, the precise number of basic units is unknown in the Chinese case. It is almost never touched upon, or varies a lot, not only between specialists and corpora, but even within the same corpus. In trying to elucidate the reason for such a different treatment in the case of the Chinese script, one cannot but focus on the first author who developed a proper analysis of the script. When Xu Shen wrote the Shuo wen jie zi , the first dictionary of Chinese characters compiled at the end of the first century, he provided a systematic analysis of more than 9 000 characters. Considering that their structure was best brought out by the older style of graphs known as the small seal script, he based his analysis on this older style, which kept graphemes more clearly apart. If compound characters can include more than 10 basic graphemes, Xu Shen basically only retained 2 main constituents to which he attributed a phonetic or a semantic function. Most characters (about 86% in Shuowen) consist in the combination of a semantic and a phonetic constituent (). In these cases, Xu Shen's distinction between semantic and phonetic constituents considerably simplified the graphic analysis. Once a constituent is attributed a phonetic function, there is no need to try to understand its meaning in a character (or provide ad hoc interpretations for it). But what about semantic compound characters without identifiable phonetic constituent, included in the other 14% characters in Shuo wen jie zi? The study of semantic compound characters is more complex and, at times, more subjective, but it allows a better understanding of Xu Shen's motivation. I shall present the different strategies and formulae (X, X, X , X Y, etc.,) employed by Xu Shen in these cases, with concrete examples, and discuss the interpretation of the relative location of the constituents (such as for example in :). The latter as well as the different kinds of motivated explanations, Xu Shen often adds, show that the graphic analysis is designed to ascertain the gloss of the character. We will see that even though Xu Shen provided some graphic analyses with 3, 4 or even 5 constituents, in most cases, he basically retained 2 main semantic constituents. Systematic and sound as it may appear, Xu Shen's analysis in terms of constituents, clearly motivated by the semantic interpretation of the characters, has eluded the fundamental question concerning the basic units of the Chinese writing system
A Realization Optimality-Theoretic approach to full and partial identity of forms
No full textIn this paper we present a Realization Optimality-Theoretic account of full and partial identity of forms, i.e., paradigmatic syncretism and cases in which lexemes share the same inflectional formative. Our approach involves both output-to-output correspondence constraints and realization constraints that associate morphosyntactic feature values with morphophonological forms. We show that Realization Optimality Theory (Xu 2007) offers a unified account of these phenomena. Additionally, we argue that Realization Optimality Theory has advantages over several alternative approaches such as feature impoverishment-plus-insertion (Noyer 1998), rules of referral (Zwicky 1985, Stump 1993), and two different models of OT morphology proposed by Müller (2007, 2008). We argue for an autonomous morphological component and also discuss related issues such as the morphology-phonology interface. We suggest that morphology and phonology are distinct components of the grammatical architecture; morphology precedes phonology by default while the morphological and phonological components overlapThe definitive version of this paper was published in Morphological Autonomy: Perspectives from Romance Inflectional Morphology (2011).Xu, Z., Arnoff, M. (2011), Morphological Autonomy: Perspectives from Romance Inflectional Morphology, in: Martin Maiden et al (eds.). Oxford: Oxford University Press.ISBN: 978-0-19-958998-2 (Published book
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