scholarly journals Islamic Copper-Based Metal Artefacts from the Garb Al-Andalus. A Multidisciplinary Approach on the Alcáçova of Mārtulah (Mértola, South of Portugal)

2021 ◽  
Author(s):  
Carlo Emanuele Bottaini ◽  
Susana Gómez-Martínez ◽  
Rui Bordalo ◽  
Massimo Beltrame ◽  
José Mirão ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Multidisciplinary Approach ◽  
Ternary Alloys ◽  
Metal Consumption ◽  
Archaeological Excavation ◽  
Economic Implications ◽  
X Ray ◽  
Metal Artefacts ◽  
Scrap Metals ◽  
Scanning Electron

Abstract A multidisciplinary approach has been applied to investigate the production technology of a collection of copper-based artefacts found during archaeological excavation campaigns carried out in the Almohad neighbourhood of Mārtulah, the Islamic name of modern Mértola (South of Portugal). In stark contrast to other Islamic materials found in the same site such as common and finely decorated pottery, glass, and bone artefacts, metal objects have received less attention despite the number of artefacts recovered. This study focuses on the chemical characterisation of 172 copper-based artefacts dating back to the 12th and the first half of the 13th centuries. The artefacts are daily use objects and consist of personal ornaments (earrings, rings, and casket ornaments), tools (spindles, spatulas, and oil lamp sticks) and artefacts with unknown functions. X-ray fluorescence Spectroscopy (XRF) and Scanning Electron Microscopy coupled with Energy Dispersive X-ray Spectroscopy (SEM/EDS), provided information not only about technological issues, as well as on the socio-economic implications of metal consumption at Islamic Mértola. The results revealed that metals were produced with a variety of Cu-based alloys, namely unalloyed copper, brasses, bronzes, and ternary alloys, by mixing Cu, Zn and Sn and Pb without any apparent consistency, as a likely result of recurrent recycling and mixing scrap metals practices or use of minerals available locally.

scholarly journals Multidisciplinary Approach Applied to the Diagnosis of the Facade of the Arciprestal Church of Santa María de Morella (Castellón, Spain)

Scanning ◽  
2019 ◽  
Vol 2019 ◽  
pp. 1-14
Author(s):  
Livio Ferrazza ◽  
María T. Pastor Valls ◽  
Gemma M. Contreras Zamorano ◽  
David Juanes Barber ◽  
Roxana Radvan ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Multidisciplinary Approach ◽  
Polarized Light ◽  
Second Phase ◽  
Wall Paintings ◽  
Preventive Conservation ◽  
X Ray ◽  
Santa Maria ◽  
Scanning Electron

This paper deals with the development of a multidisciplinary study on the current state of conservation of the facade of the Arciprestal Church of Santa María de Morella (Castellón, Spain), a work of the Gothic period of great historical and artistic value. The aim of this diagnosis was to undertake the preventive conservation actions required and increase the knowledge about the conservation of paintings on stones. During the diagnosis scanning, electron microscopy was demonstrated to be a valuable analytical method for wall paintings on stone. The facade, which since its construction has not undergone major architectural changes, has reached our days as it was configured in its creation, adding the traces of the passage of time and interventions that have suffered polychromies. Because of the conservation situation, it was decided to have an interdisciplinary project for the structural study of the work, an exhaustive study of the materials and their state of conservation. The study of the materials includes the identification of stone supports, mortars, the pictorial technique of the original and added polychromies, and the superficial patinas. On-site studies were carried out by ground penetration radar (GPR) and X-ray fluorescence (XRF). Among the techniques used in laboratory were optical polarized light microscopy (MO-LP), X-ray diffraction (XRD), scanning electron microscopy with microanalysis (SEM-EDX) and Fourier-transform infrared spectroscopy (FTIR). The study allowed to determine the different pathologies of alteration and degradation of stone substrate and polychromies, chromatic alterations, biological patinas, etc. During this study, it was demonstrated that the diagnosis of wall paintings is a complex issue that needs to be addressed in a multidisciplinary approach, where scanning electron microscopy with microanalysis is the key methodology to get a deeper understanding of subsurface characterization of wall paintings and highlight the weathering processes. In a second phase of previous studies, this technique (SEM) has been used in assessing the viability of consolidation systems and cleaning both the stone and the polychrome.

Synthesis of ternary alloys Mg2Ni0.75Pd0.25 and studies on its surface properties

1990 ◽  
Vol 5 (7) ◽  
pp. 1431-1434 ◽  
Author(s):  
Zhang Yunshi ◽  
Ji Jianhua ◽  
Yuan Huatang ◽  
Chen Shengchang ◽  
Wang Da ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Surface Properties ◽  
Ternary Alloy ◽  
Ternary Alloys ◽  
Diffusion Method ◽  
X Ray ◽  
Bet Method ◽  
Scanning Electron

The ternary alloy Mg2Ni0.75Pd0.25 was made by the Replacement-Diffusion Method (RDM). Using x-ray analysis, scanning electron microscopy, AES analysis, and the BET method, the authors were able to characterize the structure of the alloy and study its surface properties. It has been found that the alloy thus obtained has excellent surface properties compared to that prepared metallurgically.

Mechanical and tribological studies of sintered nickel-based ternary alloys

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Bukola Joseph Babalola ◽  
Ojo Jeremiah Akinribide ◽  
Olukayode Samuel Akinwamide ◽  
Peter Apata Olubambi
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Ternary Alloys ◽  
Tribological Characteristics ◽  
Indentation Hardness ◽  
Elemental Distribution ◽  
Content Type ◽  
X Ray ◽  
Mechanical And Tribological Characteristics ◽  
Scanning Electron

Purpose During the operation of nickel-based alloys as blades and discs in turbines, the sliding activity between metallic surfaces is subjected to structural and compositional changes. In as much as friction and wear are influenced by interacting surfaces, it is necessary to investigate these effects. This study aims to understand better the mechanical and tribological characteristics of Ni-17Cr-10X (X = Mo, W, Ta) ternary alloy systems developed via spark plasma sintering (SPS) technique. Design/methodology/approach Nickel-based ternary alloys were fabricated via SPS technique at 50 MPa, 1100 °C, 100 °C/min and a dwell time of 10 mins. Scanning electron microscopy, X-Ray diffraction, energy dispersive X-ray spectroscopy, nanoindentation techniques and tribometer were used to assess the microstructure, phase composition, elemental dispersion, mechanical and tribological characteristics of the sintered nickel-based alloys. Findings The outcome of the investigation showed that the Ni-17Cr10Mo alloy exhibited the highest indentation hardness value of 8045 MPa, elastic modulus value of 386 GPa and wear resistance. At the same time, Ni-17Cr10W possessed the least mechanical and wear properties. Originality/value It can be shown that the SPS technique is efficient in the development of nickel-based alloys with good elemental distribution and without defects such as segregation of alloying elements, non-metallic inclusions. This is evident from the scanning electron microscopy micrographs.

Sem Studies of Co-Cr-Mo Surgical Implant Alloy Corrosion Behavior

1982 ◽  
Vol 40 ◽  
pp. 520-521
Author(s):  
Ann Chidester Van Orden ◽  
John L. Chidester ◽  
Anna C. Fraker ◽  
Pei Sung
Keyword(s):  
Electron Microscopy ◽  
Corrosion Behavior ◽  
Anodic Polarization ◽  
Saline Solution ◽  
Saturated Calomel Electrode ◽  
Physiological Saline ◽  
X Ray ◽  
Physiological Saline Solution ◽  
Scanning Electron

The influence of small variations in the composition on the corrosion behavior of Co-Cr-Mo alloys has been studied using scanning electron microscopy (SEM), energy dispersive x-ray analysis (EDX), and electrochemical measurements. SEM and EDX data were correlated with data from in vitro corrosion measurements involving repassivation and also potentiostatic anodic polarization measurements. Specimens studied included the four alloys shown in Table 1. Corrosion tests were conducted in Hanks' physiological saline solution which has a pH of 7.4 and was held at a temperature of 37°C. Specimens were mechanically polished to a surface finish with 0.05 µm A1203, then exposed to the solution and anodically polarized at a rate of 0.006 v/min. All voltages were measured vs. the saturated calomel electrode (s.c.e.).. Specimens had breakdown potentials near 0.47V vs. s.c.e.

Identification of calcium oxalate crystals in dried or fixed tobacco leaf

1984 ◽  
Vol 42 ◽  
pp. 288-289
Author(s):  
Vicki L. Baliga ◽  
Mary Ellen Counts
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Calcium Oxalate ◽  
Growth And Development ◽  
Polarized Light ◽  
Calcium Oxalate Crystals ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Scanning Electron

Calcium is an important element in the growth and development of plants and one form of calcium is calcium oxalate. Calcium oxalate has been found in leaf seed, stem material plant tissue culture, fungi and lichen using one or more of the following methods—polarized light microscopy (PLM), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and x-ray diffraction.Two methods are presented here for qualitatively estimating calcium oxalate in dried or fixed tobacco (Nicotiana) leaf from different stalk positions using PLM. SEM, coupled with energy dispersive x-ray spectrometry (EDS), and powder x-ray diffraction were used to verify that the crystals observed in the dried leaf with PLM were calcium oxalate.

Use of SEM, X-ray analysis and TEM to localize Fe3+ reduction in roots

1988 ◽  
Vol 46 ◽  
pp. 392-393 ◽  
Author(s):  
William P. Wergin ◽  
P. F. Bell ◽  
Rufus L. Chaney
Keyword(s):  
Electron Microscopy ◽  
Root Hairs ◽  
Rapid Reduction ◽  
X Ray ◽  
Physical Evidence ◽  
Transmission Electron ◽  
Young Root ◽  
Insoluble Precipitate ◽  
Uptake And Transport ◽  
Scanning Electron

In dicotyledons, Fe3+ must be reduced to Fe2+ before uptake and transport of this essential macronutrient can occur. Ambler et al demonstrated that reduction along the root could be observed by the formation of a stain, Prussian blue (PB), Fe4 [Fe(CN)6]3 n H2O (where n = 14-16). This stain, which is an insoluble precipitate, forms at the reduction site when the nutrient solution contains Fe3+ and ferricyanide. In 1972, Chaney et al proposed a model which suggested that the Fe3+ reduction site occurred outside the cell membrane; however, no physical evidence to support the model was presented at that time. A more recent study using the PB stain indicates that rapid reduction of Fe3+ occurs in a region of the root containing young root hairs. Furthermore the most pronounced activity occurs in plants that are deficient in Fe. To more precisely localize the site of Fe3+ reduction, scanning electron microscopy (SEM), x-ray analysis, and transmission electron microscopy (TEM) were utilized to examine the distribution of the PB precipitate that was induced to form in roots.

Scanning Electron Microscopy and X-Ray Analyses of Dental Tissues from a Hibernator

1976 ◽  
Vol 34 ◽  
pp. 178-179
Author(s):  
M. L. Zimny ◽  
A. C. Haller
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Body Temperature ◽  
Ground Squirrel ◽  
Alveolar Bone ◽  
X Ray ◽  
Dental Tissues ◽  
Bone Minerals ◽  
Apical Tooth ◽  
Scanning Electron

During hibernation the ground squirrel is immobile, body temperature reduced and metabolism depressed. Hibernation has been shown to affect dental tissues varying degrees, although not much work has been done in this area. In limited studies, it has been shown that hibernation results in (1) mobilization of bone minerals; (2) deficient dentinogenesis and degeneration of alveolar bone; (3) presence of calculus and tears in the cementum; and (4) aggrevation of caries and pulpal and apical tooth abscesses. The purpose of this investigation was to study the effects of hibernation on dental tissues employing scanning electron microscopy (SEM) and related x-ray analyses.

Scanning Electron Microscopy and x-ray analysis of microparticles and early hydration effects

1995 ◽  
Vol 53 ◽  
pp. 692-693
Author(s):  
Yun Lu ◽  
David C. Joy
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
High Resolution ◽  
Morphological Development ◽  
Early Hydration ◽  
X Ray ◽  
Blended Cements ◽  
Powder Particles ◽  
Chemical Wastes ◽  
Scanning Electron

High resolution scanning electron microscopy (SEM) and energy dispersive x-ray analysis (EDXA) were performed to investigate microparticles in blended cements and their hydration products containing sodium-rich chemical wastes. The physical appearance of powder particles and the morphological development at different hydration stages were characterized by using high resolution SEM Hitachi S-900 and by SEM S-800 with a EDX spectrometer. Microparticles were dispersed on the sample holder and glued by 1% palomino solution. Hydrated bulk samples were dehydrated by acetone and mounted on the holder by silver paste. Both fracture surfaces and flat cutting sections of hydrating samples were prepared and examined. Some specimens were coated with an 3 nm thick Au-Pd or Cr layer to provide good conducting surfaces. For high resolution SEM S-900 observations the accelerating voltage of electrons was 1-2 KeV to protect the electron charging. Microchemical analyses were carried out by S800/EDS equipped with a LINK detector of take-off angle =40°.

Defects of Platelet Function Recognized by X-Ray Imaging and Scanning Electron Microscopy

1985 ◽  
Vol 43 ◽  
pp. 610-613
Author(s):  
M.G. Baldini ◽  
S. Morinaga ◽  
D. Minasian ◽  
R. Feder ◽  
D. Sayre ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Cell Biology ◽  
Imaging Technique ◽  
Human Platelets ◽  
X Rays ◽  
X Ray ◽  
X Ray Imaging ◽  
Complex Phenomena ◽  
Scanning Electron

Contact X-ray imaging is presently developing as an important imaging technique in cell biology. Our recent studies on human platelets have demonstrated that the cytoskeleton of these cells contains photondense structures which can preferentially be imaged by soft X-ray imaging. Our present research has dealt with platelet activation, i.e., the complex phenomena which precede platelet appregation and are associated with profound changes in platelet cytoskeleton. Human platelets suspended in plasma were used. Whole cell mounts were fixed and dehydrated, then exposed to a stationary source of soft X-rays as previously described. Developed replicas and respective grids were studied by scanning electron microscopy (SEM).

Environmental scanning electron microscopy of fresh human gallstones reveals new morphologies of precipitated calcium salts

1992 ◽  
Vol 50 (2) ◽  
pp. 1322-1323
Author(s):  
Howard S. Kaufman ◽  
Keith D. Lillemoe ◽  
John T. Mastovich ◽  
Henry A. Pitt
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Environmental Scanning Electron Microscopy ◽  
Environmental Scanning ◽  
X Ray Diffraction ◽  
Calcium Salts ◽  
Cholesterol Gallstones ◽  
X Ray ◽  
Ca Carbonate ◽  
Scanning Electron

Gallstones contain precipitated cholesterol, calcium salts, and proteins. Calcium (Ca) bilirubinate, palmitate, phosphate, and carbonate occurring in gallstones have variable morphologies but characteristic windowless energy dispersive x-ray (EDX) spectra. Previous studies of gallstone microstructure and composition using scanning electron microscopy (SEM) with EDX have been limited to dehydrated samples. In this state, Ca bilirubinates appear as either glassy masses, which predominate in black pigment stones, or as clusters, which are found mostly in cholesterol gallstones. The three polymorphs of Ca carbonate, calcite, vaterite, and aragonite, have been identified in gallstones by x-ray diffraction, however; the morphologies of these crystals vary in the literature. The purpose of this experiment was to study fresh gallstones by environmental SEM (ESEM) to determine if dehydration affects gallstone Ca salt morphology.Gallstones and bile were obtained fresh at cholecystectomy from 6 patients. To prevent dehydration, stones were stored in bile at 37°C. All samples were studied within 4 days of procurement.

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