bluuebunny/crossref_metadata_2025_split huggingface dataset:
A General Method for Determining the Mechanical Properties Needed for the Computer Analysis of Polymeric Structures Subjected to Changes in Temperature and Relative Humidity
Authors: Mecklenburg Marion F. , Tumosa Charles S. , McCormick-Goodhart Mark H. 
Published: March 2011

ABSTRACTThis study examines the methods for determining the effects of temperature and relative humidity (RH) on the dimensional and mechanical properties of artists' materials. Using both of these properties, typical cultural objects, such as paintings and photographs can be modeled on the computer to correlate the magnitude of developed stresses to environmental changes. Comparing these calculated stresses with the measured strength of the materials provides the opportunity to assess the potential risk from damage due to environmental change. Recognizing that the mechanical properties of polymeric materials are functions of the rate of the application of load, the time they are subjected to a load, the temperature and the relative humidity, it becomes a question of identifying those parameters that are the most important in determining the correct information needed for computer modeling.
Effects of Water on the Mechanical Properties of Paper and their Relationship to the Treatment of Paper
Authors: Vitale Timothy 
Published: March 2011

ABSTRACTThrough a series of experiments the mechanical properties of paper are explored. Hydrogen bonding is fundamental to the performance of paper and its disruption results in distinctive stress-strain behavior. Stress-strain curves were generated from which tensile strength, Young's modulus, percent stretch, and work (tensile energy absorption) were obtained.It was found that the contribution of the fiber to the mechanical properties of paper is primarily elastic. Fibers are many times stronger than paper. Only fibers which have been severely deteriorated show measurable changes in stress-strain behavior. Fiber deterioration results in characteristically different stress-strain behavior than that which results from disruption of interfiber bonding.Water immersion results in the disruption of interfiber bonds in paper, leaving only 2-3% of dry tensile strength. Interfiber bonds make a profound contribution to the mechanical properties of the paper. Aqueous treatment is shown to be a radical treatment, altering the original dried-in properties of the sheet. The release of structural bonds and dried-in strains during wetting and the subsequent reformation of interfiber bonds during drying are shown to be independent of water purity, be it ultrapure water, tap water, or water containing washing aids such as Ca(OH)2, NaOH, CaCO3 or Na2CO3.The effects of immersion in organic solvents was explored. Solvents have effects on mechanical properties which are approximately proportional to the degree of swelling caused by the solvent. Water, the liquid which caused the greatest swelling of the liquids evaluated, is shown to be the most disruptive liquid followed by methanol and acetone; toluene caused virtually no change.To explore the behavior of interfiber bonds paper was taken through a solvent exchange process. A sample was immersed in water and then taken through separate ethanol and acetone immersions to toluene, and dried. The result was a sheet with little bonding and decreases in all mechanical properties. To explore the surface tension and capillary action effects of water, the solvent-exchanged sheet was re-immersed in water. Upon drying, interfiber bonding was reintroduced which resulted in the regain of mechanical properties lost.A paradigm for the mechanical behavior of paper is developed. Fibers contribute elastic behavior and interfiber bonds are a principal source of plastic behavior.
Terracottas Around Clodion: Chemical and Mineralogical Studies and Thermoluminescence Analysis
Authors: Saltron Frédéric , Bouquillon Anne , Querré Guirec 
Published: March 2011

ABSTRACTForty one terracottas by Clodion, Marin and P. Michel, all french sculptors of the XVIIIth century, have been analyzed in the L.R.M.F.Two different kinds of analysis have been performed.The results obtained by thermoluminescence allowed to partition the works between one group contemporaneous with the Clodion period and the other one consisting of posterior works. Although the lowest limit in the use of thermoluminescence seems to be reached, the conclusions are, more often than not, in agreement with the hypotheses of the curator.X-Ray diffractometry, microprobe analysis and ion-beam methods (PIXE) have led to distinguish between siliceous pastes corresponding to artifacts created in Paris and carbonated pastes gathering terracottas made during the italian stays of the artists.
White Incrustation on Pottery From Neolithic Tell Samovodene, Bulgaria
Authors: Gencheva Julia 
Published: March 2011

ABSTRACTTwelve samples of lime plaster were examined, including a white incrustation on vessels and religious tables and the contents of a large vessel filled with the white substance. These materials are from Tell Samovodene, Bulgaria which was inhabited during the Neolithic period between 5750 and 5400 B.C. Crystal-optical analysis, X-ray diffraction, emission spectroscopy and scanning electron microscopy (SEM) were used in the analysis. It was established that the white contents of the vessel consisted of slaked lime which had been carbonized in antiquity. The white incrustation was shown to be a lime plaster, composed of slaked lime and quartz. We are continuing investigation of the kiln, found on the periphery of the tell; preliminary data suggest the kiln was used for lime burning.
Preliminary Analysis of the Masonry of the Hagia Sophia Basilica, Istanbul
Authors: Livingston Richard A. , Stutzman P.E. , Mark R. , Erdik M. 
Published: March 2011

ABSTRACTSpecimens of brick and mortar taken from the Hagia Sophia Basilica in Istanbul, Turkey, are being analyzed as part of an investigation of the construction history and present state of structural stability of the building. The analysis, covering both chemical composition and physical properties, involves a suite of instrumental methods including quantitative X-ray diffraction, thermal analysis, and automated image analysis of polished sections under SEM. These conventional methods are being supplemented by neutron diffraction and neutron and Xray small angle scattering. Preliminary results suggest the presence of cementitious materials including plombierite and tetracalcium aluminum carbonate in the mortar as well as calcium carbonate. The mortar contains significant amount of brick dust and also large chunks of brick as coarse aggregate. Given the pozzolanic nature of brick dust, it is possible that the mortar is actually not a conventional carbonated lime material, but rather a proto-concrete. The type of masonry construction involving very wide mortar joints, comparable to the width of the bricks, suggests that the Byzantine architects took advantage of this property of the mortar. This sophisticated materials technology may help to explain how the Basilica was constructed in such a short time period, and also to allow us to understand and model subsequent structural problems, including major deformations of the main piers. Also, the feasibility of dating by radiocarbon and thermoluminescence methods is being investigated to determine which parts of the elaborate buttress system are the original Byzantine structure as opposed to later Ottoman additions.
Theophilus and the Composition of Medieval Glass
Authors: Freestone Ian C. 
Published: March 2011

ABSTRACTCurrent understanding of medieval glass composition is compared with the instructions for the preparation and use of glass outlined by Theophilus in the early twelfth century. The points are illustrated by analyses of glasses from a range of objects and locations. They include the Westminster Retable, the pavement at Cluny Cathedral, Romanesque Mosan enamels on copper, Abbey windows from San Vincenzo in Italy and early enamelled glass vessels which are likely to have been made in Venice.
Physical and Cultural Constraint of Innovation in the Late Prehistoric Metallurgy of Cerro Huaringa, Peru
Authors: Epstein Stephen M. 
Published: March 2011

ABSTRACTThe arsenical copper smelting technology reconstructed from the archaeological record at the late prehistoric industrial site of Cerro Huaringa, Peru, remained unchanged for the six centuries preceding the Spanish Conquest. This lack of technological innovation is argued to be a result of the physical constraints imposed by a cultural commitment to human breath as the source of draft.
From Theophilus to C.S.Smith: Discovery of an Eleventh Century AD Bell-Casting Mold From Venosa (Southern Italy)
Authors: Vidale M. , Vaccaro A. Melucco , Salvatore M.R. , Micheli M. , Balista C. 
Published: March 2011

ABSTRACTThe recent discovery and excavation of the remains of a well preserved mold for bell-casting below the floor of the medieval church of the SS. Trinita′ of Venosa (southern Italy) provides a singular opportunity to reconstruct aspects of ancient bell-making technology and to compare the new archaeological data with the textual evidence on the same subject written by the famous monk Theophilus in the XIth chapter of his treatise “De Diversis Artibus”. Stratigraphical excavation and video-endoscopic inspection of the mold's interior allowed a preliminary reconstruction of the structure and use of this unique craft installation.
Restoration of Antique Church Bells: A Case Study
Authors: Ramos G. , Castro M.C. , Amadevilla I. , Gonzalez-Tirado C. , Castano V.M. 
Published: March 2011

ABSTRACTA 17th century bell, from Santuario-Mapethe (Mexico) was restored by using welding techniques. The work included the acoustical characterization of the bell before and after the actual welding as well as the analysis of the composition of the alloy originally employed, so a material as similar as possible to the original would be employed for the restoration. The advantages and disadvantages of the methods are discussed.
A Basic Study of Use-Wear “Polish” on Early Rice Paddy Farming Tools
Authors: Yamada Shoh 
Published: March 2011

ABSTRACTThe analysis of use-wear “polish” variation and differences according to rock types contributes to the study of the “polish” formation process. The examination of the polished surface on andesite, rhyolite and a hard variety of slate with the SEM and optical light microscope thows that the polished surfaces are produced by mild wear. This provides a basis for use-wear analysis of stone farming tools made of these rocks, which come from early Japanese rice paddy cultivation contexts.
Analysis of Medieval Fresco Pigments From the Georgian Republic
Authors: Dneprovskaya Marie 
Published: March 2011

ABSTRACTThe mineral composition of pigments from mural paintings of the 12th and 13th centuries in the grotto monasteries of Bertubani and Udabno (David-Caredga) were investigated. Apart from traditional pigments, many examples of brown-black plattnerite (PbO2) were found. They were generated by bacteriological oxidation of white lead. This oxidation process has caused great damage to the original painting color. It is necessary to investigate and to remember the potential influence of bacteria on painting pigments while conducting conservation and restoration as well as art historical analysis.
The Use of Epoxy Resins in Field Projects for Stone Stabilization
Authors: Selwitz Charles M. 
Published: March 2011

ABSTRACTThe direct application of epoxy resins to deteriorating stone often encounters problems of penetration and color formation. Conservation scientists have worked around these problems by using organic solvents as carriers and have successfully consolidated stone with epoxy resins in a large number of projects. Work in Poland, Czechoslovakia, Italy and the United States is described. In Europe the methodology has evolved to treat objects of moderate size and isolated parts of buildings while in the United States procedures have been developed for stabilizing large portions of major buildings.
Microstructures of B72 Acrylic Resin/Mtmos Composites
Authors: Wheeler George Segan , Wolkow Eugene , Gafney Harry 
Published: March 2011

ABSTRACTGels prepared from solutions of B72 acrylic resin and methyltrimethoxysilane (MTMOS) are examined by SEM. Four initial mixtures - 0,2,5 and 10% w/v B72/MTMOS - produced gels whose fractured surfaces exhibit distinct features. Scanning electron microscopy shows that neat MTMOS produces a glass-like gel while the addition of B72 creates MTMOS-derived spheres in a “connective tissue” of acrylic resin. These particle sphere/acrylic resin solids are mechanically weak composites.
Molecular Dynamics Simulations of Low-Energy Atom-Surface Interactions
Authors: Sprague J. A. , Gilmore C. M. 
Published: March 2011

ABSTRACTMolecular dynamics simulations of the deposition of atoms on crystalline surfaces have been conducted using the embedded atom method. The following atom-substrate combinations have been employed: 0.1 - 40 eV Ag deposited on (111) and (100) Ag substrates; 0.1 eV Ag deposited on (100) Cu; and 0.1 eV Cu deposited on (100) Ag. The purpose of the calculations for Ag atoms deposited on Ag substrates was to investigate the effects of adatom arrival energy and substrate orientation on the interactions of low-energy atoms with crystal surfaces. The goal of tile Ag oil Cu and Cu on Ag calculations was to observe the mechanisms producing thepreviously-reported asymmetry in epitaxy for these systems. The Ag on Ag deposition simulations demonstrated that the effects of increased atom arrival energies in promoting layerby- layer film growth and producing diffuse substrate-filn interfaces (mixing) were basically the same on the (100) and (111) surfaces. At 0. 1 eV, representative of thennal evaporation, the degree of island formation on the (100) substrate was essentially tile same as previously reported for a (111) Ag substrate. At a given atom arrival energy between 10 and 40 eV, both the redistribution into full monolayers and the mixing by surface exchange interactions were seen to occur more readily on the close-packed (111) growth surface than on the more open (100) surface. The mixing was a stronger function of crystallographic orientation. Cu was observed to grow on (100) Ag as a (100)-oriented film, with the initial film layers transfonned essentially to the bcc structure by a Bain distortion, in agreement with various experimental results. The distortion of the film layers resulted in large-amplitude soft-mode (low-frequency) lattice vibrations. Ag was observed to grow on (100) Cu as a (111)-oriented film, as experimentally observed, with the <110>-type orientations of film and substrate parallel, as predicted by previous calculations of interfacial energy.
Characterization of Ti Alloys Bombarded by keV Deuterium Ions
Authors: Chambers G.P. , Hubler G. K. , Sprague J.A. , Grabowski K.S. 
Published: March 2011

ABSTRACTThin Ti films have been bombarded at room temperature with 350–500 eV deuterium ions at current densities up to 0.5 mA/cm2. Analysis using scanning electron microscopy, x-ray diffraction, transmission electron microscopy, and secondary ion mass spectroscopy were carried out before and after bombardment. It was determined that deuterium diffuses rapidly throughout the Ti film, that the films were in a state of high compressive stress, and that the TiD2 phase was formed. No evidence of deuterium gas bubbles was found.
Epitaxial Growth of ZnTe and ZnSe on GaAs by Pulsed Laser Deposition
Authors: Rajakarunanayake Y. , Luo Y. , Aydinli A. , Lavalle N , Compaan A. 
Published: March 2011

ABSTRACTWe report the successful growth of ZnTe and ZnSe epitaxial layers on GaAs by pulsed laser deposition. A frequency doubled Nd:YAG laser was used to ablate/evaporate II-VI bulk targets and pressed powder targets in an ultra high vacuum enclosure. For typical growth temperatures in the range 200°-400°C x-ray analysis of the layers revealed sharp <100> peaks with no evidence of growth in other orientations. Polarization dependent Raman spectroscopy was also used to further characterize the epitaxial layers, by verifying the selection rules for backscattering from <100> oriented films. The low temperature photoluminescence spectra show distinct near-band-edge features indicating high crystalline quality. The photoluminescence of the films grown from bulk targets was superior to that of films grown from pressed powder targets, indicating that the use of high purity bulk targets is critical. Our results indicate that pulsed laser deposition is a promising new growth technique for the fabrication of II-VI epitaxial layers with unique advantages.
Pulsed Laser Deposition of CdTe, HgCdTe, and β-SiC Thin Films on Silicon
Authors: Fenner D.B. , Li O. , Morrison P.W. , Cosgrove J. , Lynds L. , Johansson M.E. , Stoner B.R. , Glass J.T. , Xu Peirong , Zhang Hong 
Published: March 2011

ABSTRACTThe successful methods for laser ablation and deposition of epitaxial thin films of metal oxides, especially the high-temperature superconductors (HTSC), have been adapted to pulsed laser deposition (PLD) of the narrow-band compound semiconductor HgCdTe, and the wide-band semiconductor β-SiC. Useful film quality is readily obtained in both cases: the HgCdTe films on CdTe wafers function in IR photodetection and the 3-SiC is epitaxial on both Si (100) and (111) wafers.
Ion-Beam Reactive Sputter Deposition of MgO Thin Films on Silicon and Sapphire Substrates
Authors: Chow Alice F. , Rou Shang Hsieh , Lichtenwalner Daniel J. , Auciello Orlando , Kingon Angus I. 
Published: March 2011

ABSTRACTMgO thin films were deposited on silicon and sapphire substrates using ion-beam reactive sputtering. Films have been analyzed using x-ray diffraction, transmission electron microscopy, and atomic force microscopy. Highly oriented (100) MgO films have been obtained on Si (100) substrates. The in-plane orientation is predominantly [100]MgO//[100]Si, although a twist of up to ±10° between grains is observed. Epitaxial films of MgO were deposited on four different orientations of sapphire. The MgO film orientation was (111) on c-cut (0001) Al2O3 and exhibited double positioning boundaries in TEM analysis. On r-cut (1102) Al2O3, the MgO appeared to be oriented (730) with tilt and twist of ±2° between the grains. Epitaxial MgO films oriented (110) and (111) were obtained on m-cut (1010) and a-cut (1120) sapphire orientations, respectively. In-plane directions were extracted from TEM analysis on all the samples. Atomic force microscopy revealed fairly smooth MgO films on sapphire, varying from 0.35 nm average roughness for the MgO film on the m-cut substrate to 0.80 nm on the r-cut substrate.
Influence of Low-Dose Ion-Beam Mixing on CoSi2 Formation
Authors: Dehm Ikasko C. , Ryssel H. 
Published: March 2011

ABSTRACTIn this study, the critical dose for ion-beam mixing of Co and Si with Ge-ions which results in homogenous CoSi2 formation after rapid thermal annealing was found. For this purpose, Co was deposited by sputtering on chemically cleaned, <100>-oriented Si and subsequently mixed with Ge ions at doses in the range of 2. 1014 to 1. 1015 cm−2. Silicidation was performed in a rapid thermal annealing (RTA) system at temperatures between 700° and 100°C. Rutherford backscattering measurements showed that annealing at 700°C results in an incomplete reaction when ion-beam mixing at a dose of 2.1014 cm−2 or no ion-beam mixing was performed. After annealing at 1000°C, TEM samples revealed an inhomogeneous CoSi2 film consisting of large grains embedded in the Si. Mixing at doses at or above 5.1014 cm−2 and subsequent RTA at 700°C resulted in uniform CoSi2 layers. Higher annealing temperatures cause larger grains and resistivity values as low as 18 μΩcm. Therefore, we demonstrated that the critical dose leading to complete formation of smooth CoSi2 films with abrupt interface is 5.1014 cm−2 which is nearly the same value as the amorphization dose of Ge in Si.
Modification of The Optical Properties of Al2O3 by Ion Implantation
Authors: White C. W. , Thomas D. K. , Zuhr R. A. , McCallum J. C. , Pogany A. , Haglund R. F. , Magruder R. H. , Yang L. 
Published: March 2011

ABSTRACTThe implantation of Au into A1203 followed by thermal annealing at 1100°C leads to dramatic changes in the optical properties. The linear and nonlinear optical properties are correlated to the presence of small Au precipitates which form during annealing.
Crystallization Phenomenon Induced by Proton Beam Irradiation using Large Area Ion Implantation for Polycrystalline Silicon Thin Film Transistors
Authors: Yoshinouchi A. , Morita T. , Tsuchimoto S. 
Published: March 2011

ABSTRACTCrystallization induced by proton beam irradiation using large area ion implantation at low temperature (less than 600°C) have been investigated. Phosphine gas containing hydrogen of more than 95% is discharged by RF power of 100W. Both phosphorus ions and protons are accelerated by a potential of 100kV and implanted into polycrystalline silicon (poly-Si) layers. At a range of beyond 2×1015 ions/cm2 P1 ions dose, amorphous phase is primarily formed and then changes into polycrystals again and its grain sizes grow up to 50nm in average diameter. The crystallization is found to occur simultaneously with phosphorus doping and to depend on the amount of the irradiated protons. This technique enables us to eliminate the activation annealing process for implanted dopant.
Depth Dependence and Chemical Effects in Ion Mixing of Ni on SiO2
Authors: Banwell T. C. , Nicolet M.-A. 
Published: March 2011

ABSTRACTWe report on our studies of Ni transport induced by 290 keV Xe irradiation of thin Ni films evaporated on thermally grown SiO2 at Xe fluences of 1015–1016 cm−2 and at temperatures of 77–750 K during irradiation. A simple etching technique was used to remove the free Ni leaving the SiO2 layer with incorporated Xe and Ni, whose profiles are directly measured using 2 MeV He+ backscattering spectrometry.Marker experiments are used to verify the selectivity of the etching procedure. An apparent discontinuity in the Ni concentration across the Ni-SiO2 interface may produce the high selectivity observed within our etching process. Features associated with both cascade mixing and recoil implantation are readily discernible in the residual metal profiles. An exponential tail is evident beyond ∼ 500 Å of the SiO2 and is insensitive to temperature. within 500 Å of the surface the Ni profile demonstrates a strong temperature dependence which affects both the cascade mixing and recoil implantation processes. These profiles show favorable agreement with theory for samples implanted at temperatures of ≤ 300 K, while deviations in the high temperature behavior suggest a way chemical effects may alter the collision processes.
Amorphization of Garnet by Ion Implantation
Authors: Guzman A. M. , Yoshiie T. , Bauer C. L. , Kryder M. H. 
Published: March 2011

ABSTRACTAmorphization by ion implantation has been investigated in films of (SmYGdTm)3Ga0.4Fe4.6O12 garnet by transmission electron microscopy, incorporating a special cross-sectioning technique. These films were produced by liquid phase epitaxy on (111) garnet substrates and subsequently implanted with ions of deuterium at 60 keV and doses ranging from 0.50 to 4.5×1016 D2+/cm2 and ions of oxygen at 110 keV and doses ranging from 0.95 to 8.6×1014O+/cm2. The amorphization process proceeds in separate stages involving the formation of isolated amorphous regions, merging of these regions into a continuous band and subsequent propagation of the amorphous band toward the implanted surface. Details of these processes are interpreted in terms of various atomic displacement mechanisms.