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Journal of Wuhan University of Technology(Materials science) 2005年第B12期20卷 10-12页

作者： s Deb ja Roether Department of Biomaterials King's College London School of Dentistry at the Guy's King's & St Thomas Hospital Guy's Tower Guy's Hospital London Bridge London SE 1 9RT UK

Bioactive bone cements based on a paste-paste system for orthopaedic applications were developed consisting of hydroxyapatite （ HA ） filler panicles in a methacrylate matrix comprising urethane dimethacrylate （ UDMA ） and triethylene glycol dimethacrylate （ TEGDMA ）. To improve the interface between inorganic filler and organic matrix the HA panicles were subjected to two different surface treatment methods, using polyacrylic acid （PAA） and γ-methacryloxy propyl trimethoxy silane （γMPs）. The aim of the present study was to determine the influence of surface treatment and the inclusion of multifunctional methacrylates on the mechanical properties, namely 3-point flexural strength （Fs） and fracture toughness of the cements and the effect of ageing in simulated body fluid. Comparing the mechanical properties of the two cements, the γMPs- HA cement showed that the fracture toughness of the experimental bone cements were significantly greater （ p 〈 0.001） compared to that of the PMMA cement, whereas PAA-HA containing cement had strength vollues around 20% lower. interestingly, PAA was found to be more effective in improving the interface as the PAA treated HA cement （ UTHAPPA ） maintained its strength on immersion in sBF, suggesting that PAA provided a coupling, which was less sensitive to moisture, a similar trend was also observed with the inclusion of the carboxyl containing multifunctional methacrylates.

关键词： bioactive bone cements coupling agents composites polyacrylic acid

Association between Tropical Convection and Boreal Wintertime Extratropical Circulation in 1982/83 and 1988/89

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Advances in Atmospheric sciences 2003年第4期20卷 593-603页

作者： ja-Yeon MOON Kyung-ja HA Climate Research Laboratory Meteorological Research InstituteSeoul156-720KoreaDepartment of Atmospheric SciencesPusan National UniversityPusan609-735Korea

Boreal wintertime extratropical circulation is studied in relation to the tropical convection during the 1982/83 El Niño and 1988/89 La Niña. The anomaly structure of 1982/83 and 1988/89 over the extratropics reveals remarkably different features as the longitudinal tropical forcing region changes. The Rossby wave source (Positive) shows the largest maximum over East Asia in both years due to the persistent heating from the western Pacific warm pool area. However, the sink term shows contrasting features over the subtropics and extratropics between the two years. in the El Niño year, enhanced tropical convection over the eastern Pacific produces the Rossby wave sink at 10°N and shifted eastward over the North Pacific, while in the La Niña year, the sink area is shifted westward over the North Pacific. The contrasting features between the two events in mean-eddy interaction appears especially over the downstream area of the East Asian Jet. The extension (retraction) of the meanflow eastward (westward) to the east (west) of the dateline is related with the effect of the westward (eastward) E-vector and the strengthening (weakening) of the negative anomalies of the barotropic growth of kinetic energy. Hence, almost opposite characteristics between the two events can explain the close relationship of tropical convection and the extratropical internal variability.

关键词： tropical convection extratropical circulation rossby wave source mean-eddy interaction

Ductile Phase Toughened Brittle Materials

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Journal of Materials science & Technology 1996年第2期12卷 124-134页

作者： sun, XD Yeomans, ja UNiV sURREY DEPT MAT SCI & ENGNGUILDFORD GU2 5XHSURREYENGLAND

Toughening of brittle materials by the inclusion of ductile phases is governed by several important factors which include ceramic-ductile phase interfacial bond strength, physical and chemical compatibility between ceramic and ductile phase, geometry and mechanical properties of ductile phase. The present understanding of the effect of these factors on toughening is reviewed and clarified. Continuous ductile phases (network, fibre or plate) are found to be more efficient for the toughening of brittle materials than discrete ductile particles. However, ductile particle toughened brittle materials have the advantages of material homogeneity, isotropy, and particularly better high temperature properties. it has been demonstrated that the influence of interfacial bond strength is determined by the geometry of the ductile phase in the composites. For the comparatively continuous ductile phase, such as ductile network, fibre or plate, comparatively weak interfacial bond strength can promote partial debonding of the brittle matrix-ductile phase interface during crack propagation and is beneficial for toughening. For discrete particulate ductile phase toughened brittle materials, the small gauge length of the ductile phase often results in the ductile phase pull-out during crack propagation which is the main limitation to toughening. Thus strong bond strength is required to ensure the bridging of the crack by the ductile phase. The coefficient of thermal expansion (CTE) mismatch between matrix and ductile phase has also been correlated with the geometry of the ductile phase. in most of the ceramic/metal systems, the CTE of the ductile metal phase is greater than that of the ceramic matrix. in the case of ductile network, fibre or plate, the residual stress created by the CTE mismatch can contribute to toughening through its influence on the initial crack opening stress while the bridging of the crack by the ductile phase is still ensured. However, for discrete ductile parti

关键词： Brittleness

ON TRANsMissiON PROBLEM FOR KiRCHHOFF TYPE WAVE EQUATiON WiTH A LOCALiZED NONLiNEAR DissiPATiON iN BOUNDED DOMAiN

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Acta Mathematica scientia 2012年第3期32卷 893-906页

作者： Jeong ja Bae Department of Mathematics Dongeui UniversityPusan 614-714Korea

in this article, we consider the global existence and decay rates of solutions for the transmission problem of Kirchhoff type wave equations consisting of two physi- cally different types of materials, one component is a Kirchhoff type wave equation with nonlinear time dependent localized dissipation which is effective only on a neighborhood of certain part of the boundary, while the other is a Kirchhoff type wave equation with nonlinear memory.

关键词： Existence of solution uniform decay transmission problem Kirchhoff type wave equation boundary value problem localized dissipation

On Uniform Decay for Transmission Problem of Kirchhoff Type Viscoelastic Wave Equation

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Acta Mathematica sinica,English series 2010年第7期26卷 1197-1206页

作者： Jeong ja BAE Department of Mathematics Dongeui University

in this paper we consider the large time behavior of solutions to an n-dimensional transmission problem for two Kirchhoff type viscoelastic wave equations, that is, the wave propagation over bodies consisting of two physically different types of materials. One component is a simple elastic part while the other is a viscoelastic component endowed with a long range memory. We show that the dissipation produced by the viscoelastic part is strong enough to produce exponential or polynomial decay of the solution

关键词： existence of solution uniform decay wave equation boundary value problem a priori estimates

GLOBAL EXisTENCE FOR THE NONHOMOGENEOUs QUAsiLiNEAR WAVE EQUATiON WiTH A LOCALiZED WEAKLY NONLiNEAR DissiPATiON iN EXTERiOR DOMAiNs

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Acta Mathematica scientia 2009年第5期29卷 1203-1215页

作者： Jeong ja Bae Department of Mathematics University of Ulsan

it is proved that the global existence for the nonhomogeneous quasilinear wave equation with a localized weakly nonlinear dissipation in exterior domains.

关键词： quasilinear wave equation localized weakly nonlinear dissipation exterior domains

Post-translational modifications of prostaglandin-endoperoxide synthase 2 in colorectal cancer:An update

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World Journal of Gastroenterology 2018年第48期24卷 5454-5461页

作者： Rafael i jaén Patricia Prieto Marta Casado Paloma Martín-sanz Lisardo Boscá Department of Metabolism and Physiopathology of inflammatory Diseases Instituto de Investigaciones Biomédicas Alberto Sols (CSIC-UAM) Department of Biomedicine Instituto de Biomedicina de Valencia (CSIC) Centro de investigación Biomédica en Red de Enfermedades Cardiovasculares y Hepáticas y DigestivasISCⅢ Unidad Asociada iiBMULPGC Universidad de las Palmas de Gran Canaria (ULPGC)

The biosynthesis of prostanoids is involved in both physiological and pathological processes. The expression of prostaglandin-endoperoxide synthase 2(PTGs2; also known as COX-2) has been traditionally associated to the onset of several pathologies, from inflammation to cardiovascular, gastrointestinal and oncologic events. For this reason, the search of selective PTGs2 inhibitors has been a focus for therapeutic interventions. in addition to the classic non-steroidal anti-inflammatory drugs, selective and specific PTGs2 inhibitors, termed coxibs, have been generated and widely used. PTGs2 activity is less restrictive in terms of substrate specificity than the homeostatic counterpart PTGs1, and it accounts for the elevated prostanoid synthesis that accompanies several pathologies. The main regulation of PTGs2 occurs at the transcription level. in addition to this, the stability of the mRNA is finely regulated through the interaction with several cytoplasmic elements, ranging from specificmicroR NAs to proteins that control mR NA degradation. Moreover, the protein has been recognized to be the substrate for several post-translational modifications that affect both the enzyme activity and the targeting for degradation via proteasomal and non-proteasomal mechanisms. Among these modifications, phosphorylation, glycosylation and covalent modifications by reactive lipidic intermediates and by free radicals associated to the proinflammatory condition appear to be the main changes. identification of these post-translational modifications is relevant to better understand the role of PTGs2 in several pathologies and to establish a correct analysis of the potential function of this protein in diseases progress. Finally, these modifications can be used as biomarkers to establish correlations with other parameters, including the immunomodulation dependent on molecular pathological epidemiology determinants, which may provide a better frame for potential therapeutic interventions.

关键词： Prostaglandins Prostaglandin-endoperoxide synthase 2 Post-translational modifications Glycosylation Colorectal cancer inflammation

Nuclear Planetology:Especially Concerning the Moon and Mars

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Research in Astronomy and Astrophysics 2012年第10期12卷 1313-1380页

作者： Kyeong ja Kim Nobuyuki Hasebe Korea institute of Geoscience and Mineral Resources Daejeon305-350 Korea Research institute for science and Engineering Waseda UniversityShinjukuTokyo 169-8555 Japan

To approach basic scientific questions on the origin and evolution of plan- etary bodies such as planets, their satellites and asteroids, one needs data on their chemical composition. The measurements of gamma-rays, X-rays and neutrons emit- ted from their surface materials provide information on abundances of major elements and naturally radioactive gamma-ray emitters. Neutron spectroscopy can provide sen- sitive maps of hydrogen- and carbon-containing compounds, even if buried, and can uniquely identify layers of carbon-dioxide frost. Nuclear spectroscopy, as a means of compositional analysis, has been applied via orbital and lander spacecraft to extrater- restrial planetary bodies： the Moon, Venus, Mars, Mercury and asteroids. The knowl- edge of their chemical abundances, especially concerning the Moon and Mars, has greatly increased in recent years. This paper describes the principle of nuclear spec- troscopy, nuclear planetary instruments carried on planetary missions so far, and the nature of observational results and findings of the Moon and Mars, recently obtained by nuclear spectroscopy.

关键词： nuclear planetology: planetary remote sensing -- elemental mapping --nuclear science payloads -- chemical abundance

sensitivity to Combustible Gas for ZnO Thin Films

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Journal of Materials science & Technology 1997年第4期13卷 302-305页

作者： Tan, GL Wu, ja Wu, XJ Dept. of Materials science and Engineering Zhejiang University Hangzhou 310027 China

A fine polycrystalline ZnO thin film with 0.3 similar to 0.6 mu m grain size was obtained by sol-gel process and a consequential heat treatment at 500 degrees C. The process of preparing ZnO thin film was analysed. The sensitivity and conductivity of ZnO thin films as combustible gas (CO, CH4, H-2) sensor as well as the influence of catalyst and pH value of the precursor on its sensitivity were studied in detail. The structure characteristics of ZnO thin film by different process were investigated by X-ray diffraction, thermal analysis and photoelectron spectrometer. The atomic ratio of Zn to O on the surface of ZnO thin film was found to be 1.14:1 measured from XPs result. The conductivity of the thin film increases greatly when doped with Al3+ ion but decreases while doped with Na+ ion.

关键词： Zinc oxide

Multirange Fractal Analysis on the Negative Correlation between Fractal Dimension of Fractured surface and Toughness of Materials

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Journal of Materials science & Technology 1996年第4期12卷 318-320页

作者： Lung, CW Jiang, ja Zhang, CH international Centre for Materials Physics Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China

Applying the concept of multirange fractals, a new explanation to the Williford's multifractal curve on the relationship of fractal dimension with fracture properties in materials has been given. it shows the importance of factorizing out the effect of fractal structure from other physical causes and separating the appropriate range of scale from multirange fractals.

关键词： Fracture