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Characterization of AL-Y alloy thin films deposited by direct current magnetron sputtering

Journal of Vacuum science & Technology B: Microelectronics Processing and Phenomena 1997年第6期15卷 1990-1990页

作者： Liu, Y. Singh, R. Poole, K. Diefendorf, R.J. Harriss, J. Cannon, K. Materials Science and Engineering Program Clemson University Clemson South Carolina 29634 Department of Electrical and Computer Engineering Materials Science and Engineering Program Clemson University Clemson South Carolina 29634 Department of Ceramic Engineering and Materials Science and Engineering Program Clemson University Clemson South Carolina 29634 Department of Electrical and Computer Engineering Clemson University Clemson South Carolina 29634 Cryovac North America W. R. Grace & Co. Duncan South Carolina 29334

Thin films of Al-1.27 wt %Y were deposited by dc magnetron sputtering. Adding yttrium to the aluminum drastically reduced the metal’s grain size and also improve the uniformity of grain size distribution. Upon annealing at a temperature of 450 °C for 30 min, grain growth was insignificant, while the electrical resistance dropped from 6.05 to 2.95 μΩ cm. The as deposited films consisted of Al4Y and α-Al supersaturated with yttrium. After annealing, β-Al3Y precipitated instead of α-Al3Y. The Al–Y films had much higher resistance to hillock formation than did Al-1 wt %Si films.

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Optical fiber mechanical testing techniques

Optical fiber mechanical testing techniques

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Fiber Optics Reliability and Testing: A Critical Review 1993

作者： John Matthewson, M. Rutgers Univ. Fiber Optic Materials Research Program Department of Ceramic Science and Engineering PiscatawayNJ08855 United States

This paper reviews the common techniques for mechanical testing of optical fiber specimens and compares and contrasts their attributes. Any technique must be able to grip the specimens without causing failure at the grips. The techniques generally fall into two categories;uniaxial tensile testing in which the fibers must be gripped carefully, and bending techniques which reduce the local stress at the grips. The former techniques generally give results that are easier to interpret due to the homogeneous stress field but are experimentally the least convenient. In contrast, bending techniques are experimentally convenient, but due to the inhomogeneous nature of the stress field developed and the short fiber test lengths, may not be as useful as tension for some purposes. © COPYRIGHT SPIE. Downloading of the abstract is permitted for personal use only.

关键词： Tensile testing

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Optical fiber reliability models

Optical fiber reliability models

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Fiber Optics Reliability and Testing: A Critical Review 1993

作者： John Matthewson, M. Rutgers Univ. Fiber Optic Materials Research Program Department of Ceramic Science and Engineering PiscatawayNJ08855 United States

Systems containing optical fiber have design lives on the order of decades so that models for assessing the mechanical reliability of the fiber must rely on extrapolations from accelerated short term testing. Such extrapolations are only valid if all relevant mechanisms are fully understood. The physical processes giving rise to mechanical degradation are reviewed and it is shown that no single model describes all situations. In particular, strong "pristine" fiber can behave quite differently from weaker fiber. Additionally, two degradation regimes are identified, one which is stress assisted (fatigue) and one which can occur even in the absence of applied stress (aging). Recent advances in understanding these phenomena are discussed and promising areas for future work are proposed. © COPYRIGHT SPIE. Downloading of the abstract is permitted for personal use only.

关键词： Optical fibers

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Utilization of ornamental rock waste as a catalytic support for α-MoO₃ in biodiesel production

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Scientific reports 2025年第1期15卷 19152页

作者： H B Sales M S Oliveira A L Silva H L Pereira A C F M Costa M C F Alves Laboratory of Ceramic Materials Synthesis (LabSMac) Graduate Program in Materials Science and Engineering (PPGCEMat) Academic Unit of Materials Engineering (UAEMa) Federal University of Campina Grande (UFCG) Rua Aprígio Veloso 882 Bodocongó 58.429-900 Campina Grande PB Brazil. herbet_bezerra@***. Laboratory of Ceramic Materials Synthesis (LabSMac) Graduate Program in Materials Science and Engineering (PPGCEMat) Academic Unit of Materials Engineering (UAEMa) Federal University of Campina Grande (UFCG) Rua Aprígio Veloso 882 Bodocongó 58.429-900 Campina Grande PB Brazil. Laboratory of Inorganic Materials for Environmental Catalysis Research Department of Chemistry (MATIPECA) Graduate Program in Chemistry (PPGQ) DQ State University of Paraíba (UEPB) Rua Baraúnas 351 Universitário 58.429-500 Campina Grande PB Brazil.

This study aimed to explore the use of ornamental stone waste as a support for the α-MoO₃ catalyst to develop efficient and sustainable heterogeneous systems for biodiesel production. The catalysts were characterized using physicochemical techniques including X-ray diffraction with Rietveld refinement, FTIR and Raman spectroscopy, scanning electron microscopy with EDS, transmission electron microscopy, nitrogen adsorption/desorption (BET method), particle size distribution, ammonia temperature-programmed desorption (TPD-NH₃), magnetic measurements, and gas chromatography to analyze simultaneous transesterification/esterification (TES) reactions and quantify methyl and ethyl esters. XRD patterns revealed crystalline phases such as mica-biotite, ferro-tschermakite, albite, quartz, and iron-magnesium silicates-components of the catalytic support-as well as orthorhombic α-MoO₃ phases, also confirmed in the heterogeneous systems. FTIR and Raman analyses showed characteristic vibrational bands, while SEM images displayed irregular agglomerates, corroborated by TEM. Nitrogen adsorption isotherms indicated mesoporous structures with surface areas ranging from 0.615 to 3.87 m²/g. Particle size analysis showed D₅₀ values between 5.02 and 20.00 μm, with total acidity ranging from 77.0 to 245 µmol/g of NH₃. Magnetic tests indicated ferrimagnetic behavior. The catalytic performance confirmed the effectiveness of the waste as a support for α-MoO₃, particularly in the system containing 40% Mo ions (40%σ-MoO₃:Waste), which achieved conversions between 78% and 95%. These findings highlight the environmental and technological potential of the studied catalysts, reinforcing the economic viability and ecological relevance of reusing industrial waste in the sustainable production of biodiesel from waste oils.

关键词： And sustainability Green technology Heterogeneous catalysis Industrial waste MoO₃ Waste oils

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Influence of Biomimetic Apatite Coating on the Biobehavior of TiO_(2)Scaffolds

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Journal of Bionic engineering 2024年第4期21卷 1975-1986页

作者： Shima Mahtabian Seyed Mehdi Mirhadi Nahid Hassanzadeh Nemati Melika Sharifi Fariborz Tavangarian Department of Biomedical Engineering University of DelawareNewarkDE19716USA Department of Ceramic Engineering Islamic Azad University(Shahreza Branch)ShahrezaIsfahan86145-311Iran Department of Biomedical Engineering Islamic Azad University(Science and Research Branch)TehranIran Mechanical Engineering Program School of ScienceEngineering and TechnologyPennsylvania State UniversityHarrisburgMiddletownPA17057USA Department of Materials Science&Engineering Islamic Azad University(Najaf Abad Branch)Najaf AbadIsfahan***Iran Biomedical Engineering Department Pennsylvania State UniversityState CollegeUniversity ParkPennsylvania16802USA

Immersion of scaffolds in Simulated Body Fluid(10SBF)is a standardized method for evaluating their bioactivity,simulating in vivo conditions where apatite deposits can be formed on the surface of scaffold,facilitating bone integration and ensuring their suitability for bone implant purposes,ultimately contributing to long-term implant *** effect of apatite deposition on bioactivity and cell behavior of TiO_(2)scaffolds was *** were soaked in 10SBF for different durations to form HAP layer on their *** results proved the development of a hydroxyapatite film resembling the mineral composition of bone Extracellular Matrix(ECM)on the TiO_(2)*** XRD test findings showed the presence of hydroxyapatite layer similar to bone at the depth of 10 nm.A decrease in the specific surface area(18.913 m^(2)g^(−1)),the total pore volume(0.045172 cm^(3)g^(−1)(at p/p0=0.990)),and the mean pore diameter(9.5537 nm),were observed by BET analysis which confirmed the formation of the apatite *** was found that titania scaffolds with HAP coating promoted human osteosarcoma bone cell(MG63)cell attachment and *** seems that immersing the scaffolds in 10SBF to form HAP coating before utilizing them for bone tissue engineering applications might be a good strategy to promote bioactivity,cell attachment,and implant fixation.

关键词： Titania Hierarchical meso/macro porous 10SBF Biomimetic apatite Coating

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Fiber lifetime predictions

Fiber lifetime predictions

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Fiber Optic Components and Reliability 1991

作者： Matthewson, M.J. Rutgers University Fiber Optic Materials Research Program Department of Ceramic Science and Engineering P. O. Box 909 PiscatawayNJ08855-0909 United States

A computer program is described that can analyze optical fiber fatigue data from a variety of fatigue experiments and for a variety of crack growth kinetics models and can then predict long term static fatigue behavior. The key feature of the program is its' ability to analyze the statistical uncertainty in the predictions due to scatter in the data to which the models are fitted. It is shown that uncertainty in the lifetime predictions is often dominated by the uncertainty in the choice of the appropriate crack growth model. It is therefore concluded that a range of models should be considered when making lifetime predictions. © 1991 SPIE. All rights reserved.

关键词： Growth kinetics

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THE INFLUENCE OF SOLUBILITY ON THE RELIABILITY OF OPTICAL FIBER

THE INFLUENCE OF SOLUBILITY ON THE RELIABILITY OF OPTICAL FI...

引用

CONF ON OPTICAL MATERIALS AND TESTING : BENIGN AND ADVERSE ENVIRONMENTS

作者： MATTHEWSON, MJ RONDINELLA, VV KURKJIAN, CR Rutgers University Fiber Optic Materials Research Program Department of Ceramic Science and Engineering Piscataway 08855 NJ United States ATandT Bell Laboratories 600 Mountain Avenue Murray Hill 07974 NJ United States

ISBN: (纸本)0819409707

Recent advances in the understanding of reliability of silica optical fiber indicate that the chemical durability of the fiber can control the long duration lifetime both under stress-induced fatigue and zerostress aging conditions. In particular, dissolution of surface material produces strength degrading surface roughness. These mechanisms are discussed and strategies for improving reliability by inhibiting dissolution are examined. As an example, a modified polymer coating formulation is described that is shown to increase the lifetime of the fiber by up to a factor of thirty-fold. Strategies for improving the strength and durability of non-oxide fibers using a similar approach are also discussed. © 1993 SPIE. All rights reserved.

关键词： Optical fibers

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Metastable States During Devitrification of a Zr70Pd20Cu10 Metallic Glass

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MRS Online Proceedings Library 2004年第1期805卷 218-228页

作者： Kramer, M. J. Sordelet, D. J. Metal and Ceramic Sciences Program Ames Laboratory (USDOE) Department of Materials Science and Engineering Iowa State University Ames USA

High energy synchrotron x-rays (124.63 keV) are used to investigate the initial stages of the devitrification for the Zr70Pd20Cu10 metallic glass prepared by melt-spinning (MS). Due to the excellent signal:noise, we are able to determine the initial nucleating phase by analyzing the differences in the total scattering function S(Q) as a function of time at a temperature ~ 50 K below the crystallization temperature. The alloy undergoes a structural relaxation prior to nucleation and growth. Devitrification proceeds from nucleation of the icosahedral phase. The differential pair distribution function (dPDF) indicates that the as-quenched alloy may have icosahedral-like order which undergoes local rearrangement to true icosahedral order at an annealing temperature 50 K below the crystallization temperature. More importantly, time-resolved high-energy synchrotron is shown to have excellent sensitivity to the initial atomic rearrangements preceding nucleation in metallic glasses.

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Emergent process methods for high technology ceramics

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Materials science and engineering 1985年第1期75卷 217-218页

作者： G.L. Messing Ceramic Science and Engineering Program Department of Materials and Engineering The Pennsylvania State University University Park PA 16802 U.S.A.

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Microcellular Al2O3 ceramics from wood for filter applications

Microcellular Al2O3 ceramics from wood for filter applicatio...

引用

作者： Rambo, Carlos Renato Andrade, Tarcisio Fey, Tobias Sieber, Heino Martinelli, Antônio Eduardo Greil, Peter Materials Science and Engineering Graduate Program-PGMAT Chemical Engineering Department-EQA Federal University of Santa Catarina 88040-900 Florianópolis SC Brazil Materials Science and Engineering Graduate Program-PPGCEM UFRN-Federal University of Rio Grande Do Norte 59072-970 Natal RN Brazil Department of Materials Science Glass and Ceramics University of Erlangen-Nuremberg D-91058 Erlangen Germany American Ceramic Society

Microcellular biomorphous Al2O3 was produced by Al-vapor infiltration in pyrolyzed rattan and pine wood-derived biocarbon preforms. At 1600°C the biocarbon preforms reacted with gaseous aluminum to form Al4C3. After oxidation in air at temperatures between 1550° and 1650°C, for 3 h, the biocarbon preforms were fully converted into α-Al2O3. Owing to the high anisotropy of biomorphous Al2O3, the compressive strength behavior was strongly dependent on the loading direction. The compressive strength of the specimens (0.1-11 MPa) is strongly dependent on their overall porosity and their behavior could be explained using the Gibson-Ashby model. The Darcian permeability (k1), as well as the non-Darcian permeability (k 2), increased with an increase of the total porosity. The Darcian permeability of biomorphous Al2O3 was found to be in the range of 1-8 × 10-9 m2, which is in the order of magnitude of gas filters, and, therefore, suitable for several technological applications. © 2008 The American ceramic Society.

关键词： Wood products

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