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In the present study, the CALPHAD (CALculation of PHAse Diagrams) methodology and thermodynamic data were used to calculate the equilibrium phase diagram of the Zr-Fe-Al system. Furthermore, the information for the enthalpy of mixing (ΔHmix) and the atomic radius of the constituent elements, in terms of the generalized topological instability factor (λ), were combined with the ternary phase diagram to predict compositions with high Glass Forming Ability (GFA). Compositions with a Zr content ranging from 67 to 73 at. % were proposed and later produced by rapid cooling using suction casting. The obtained results revealed that 12 out of the initial 14 compositions were successfully made into glassy structures with a critical diameter ranging from 0.5 to 2.5 mm. The achieved results show good agreement between the predictions made and the experimental results, and the corresponding λ value obtained for the highest GFA was used to identify the optimum area of interest for producing Zr-Fe-Al metallic glasses. It is believed that the proposed computational approach can be used as a guideline to predict glass forming areas/compositions in even other systems. [ABSTRACT FROM AUTHOR]

The article provides information on an English translation of Antonio Neri's "L'arte vetraria" (The art of glass), presented by physician Christopher Merrett to his fellow members of the Royal Society at the meeting of the Society on October 8, 1662 in London, England. Topics discussed include an inventory of materials relevant to glassmaking, dedicatory remarks by Neri in his treatise, and a microhistory of glass as both industrial commodity and tangible curiosity in early modern England.

It has long been assumed that lead glazing technology preceded glassmaking in the Western world and that the technological transfer was from glazes to glass. Here, we present new evidence for the reverse, the indigenous innovation of glassmaking and its transfer to glazes in early Islamic al-Andalus (Spain). Compositional analyses show that Islamic lead glazes from Córdoba are intimately related to a distinct type of high-lead glass, suggesting a connection between the two technologies. The archaeological remains from a pottery workshop indicate that the glazing process initially involved the production of a lead glass and is not linked to earlier Roman or other contemporary glazing technologies. The data also demonstrate that the potters not only used the same materials and techniques but borrowed stylistic and decorative models from glassmaking. [ABSTRACT FROM AUTHOR]

This essay considers the emergence of post-industrial China through an examination of the 'social' and 'antisocial' lives of an industrial glass-forming machine. By reviewing the process through which glass-forming technology developed in China, the closure of industrial glass manufacturing in Shanghai, and the adoption of an abandoned glassforming machine by the Shanghai Museum of Glass, the essay reflects on the ways in which one formerly industrial district has begun to negotiate its multiple and sometimes conflicting identities. [ABSTRACT FROM AUTHOR]

The article discusses research articles published in "Science" journals, including finding evidence of dating the origin of the Maya calendar, increasing the actuation stress of a hydrogel, and synthesis of delicate glass parts. The articles published in other journals include healing by gene therapy, racial discrimination against African American drivers in the US, and plant control of mammalian cells.

The present article is dedicated to periods in the ancient history of glass-making when the art blossomed: the beginnings in the second millennium BCE in Mesopotamia and Egypt, and the first century CE, when glassblowing spread in the Roman Empire. While the appreciation of glass during these times has been generally acknowledged, the details of what glass really meant have been little studied. This article broadly looks at the mentalities that could have shaped ancient opinions about glass. For the early period, the focus is on the relation of these cultures to stone, the natural model for glass, as becomes apparent in the Mesopotamian epic Ninurta and the Stones. For the Roman period, texts by Pliny the Elder, Seneca, and others are discussed. The article aims at showing the fascinating diversity of potential meanings of glass in the ancient world. [ABSTRACT FROM AUTHOR]

In this work, a series of dense arc-sprayed Fe-B-Si-Nb-Cr-Mo glassy coatings were developed. The effects of Cr and Mo on glass formation and mechanical properties were explored in details. The coatings have a full glassy state. Thermal stability of the coatings increases remarkably with addition Cr and Mo. The onset crystallization temperature ( T x ) increases from 797 K to 912 K. The hardness increases from 16.4 GPa to 18.7 GPa. The relatively wear resistance of the FeBSiNbCrMo glassy coating is about 7.8 times and 1.5 times that of Q235 steel and the FeBSiNb coating, respectively. The corrosion resistance in 3.5 wt% NaCl solution reveals that the FeBSiNbCrMo glassy coating has the lowest I corr and the highest fitted R t . An attempt has been established to discuss correlations between structural characteristics and mechanical properties of the coatings with different elements. [ABSTRACT FROM AUTHOR]

Abstract: The research on manuscripts provides useful information about the artistic/technical production and the scientific development in the past. However, the reproduction of the ancient recipes is difficult because most of them are described generally or they hide essential information to preserve the production secrets. In this study, four different recipes from the medieval Manuscript H‐490 (École de Médicine of Montpellier University, France) were reproduced. The raw materials and the production process of each recipe were discussed from the point of view of the glassmaking, and the final products were characterized. The recipe (31) indicated the preparation of a white glaze, similar to Islamic frits. The recipes (32) and (33) explained the preparation of an “unbreakable” glass; however, the characterization of the final products showed that no changes in the hardness of the glass were obtained. And the recipe (34) described the preparation of a green glass which was successfully obtained. [ABSTRACT FROM AUTHOR]

Pliny the Elder describes the discovery of a process for making natron glass, which was widely used for much of the first millennium BC and AD. His account of glassmaking with natron has since been corroborated by analyses of archaeological glass and the discovery of large-scale glass production sites where natron glass was made and then exported. Analyses of Egyptian natron have shown it to be a complex mixture of different sodium compounds, and previous experiments to make glass with Egyptian natron have been unsuccessful. Here, natron from el-Barnugi in the Egyptian Nile delta, a site which also probably supplied Roman glassmakers, is used to produce glass. The experiments show that high-quality glass, free of unreacted batch or bubbles, could have been produced from natron in its unprocessed form in a single stage, that larger quantities of natron would be required than has previously been anticipated, that the presence of different sodium-containing compounds in the deposit aided melting, and that negligible waste is produced. The implications for the identification of glass production sites, for the organisation of trade and for the supply of natron within and outside Egypt are discussed in the light of Pliny’s accounts. [ABSTRACT FROM AUTHOR]

In a number of industries (ferrous and nonferrous metallurgy, glass-making and silicate-producing technologies), interaction between refractory materials with melts results in sequences of reaction zonation (reaction columns) that show all principal features of diffusion-controlled metasomatic zoning. However, in contrast to the latter, reaction melt is generated together with crystalline phases in the rear zones of the columns. This melt is neither mechanically displaced melt that affects the refractory materials, nor produced by melting. The process generating this melt is most adequately defined as replacement by melt. The principal characteristics of the zoning are discussed below with reference to the corrosion of chromite-periclase refractory materials with melted slag in nickel-producing metallurgy. Similarities between the relations observed under different conditions and in different systems and the evolutionary dynamics of the process, specifics of melt generation and changes in its composition in the zones are demonstrated below with the use of data on other technologies and their experimental modeling. The mechanism of melt replacement is applicable to describing natural reaction processes of magma interaction with host rocks (magmatic replacement), with the following unobvious implications. (1) It is reasonable to expect that the minerals of the rocks should host melt inclusions. (2) It is reasonable to expect that certain minerals should be found in two distinct populations: (i) those in equilibrium with melt in the reaction column and (ii) those crystallizing from the cooling melt. (3) Two or more zones of the column can consist of the same minerals, but their proportions should be different. (4) Plastic deformations in the rear zones of the column (magmatic replacement) should be associated with brittle ones in the pristine host rocks and frontal (metasomatic) zones. (5) In contrast to the rocks of metasomatic columns, the material of magmatic-replacement zones can flow through fractures cutting across the host metasomatic rocks and thereby intersect the outer metasomatic zones. [ABSTRACT FROM AUTHOR]

A study to determine suitability of the low grade Kalambaina limestone deposit for glass making has been carried out. Samples were collected from four different locations. The representative samples were analyzed and characterized to determine the chemical composition, mineral phase and microstructural morphology using X-ray fluorescence (XRF), X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM) respectively. The results of the XRF showed thatthe deposit consists of 45.66 wt% CaO, 0.38 wt% MgO, 0.35 wt% Fe2O3, 0.22 wt% Al2O3, 1.13 wt% SiO2, 0.19 wt% TiO2 and the amount of material lost on ignition was 42.99% (LOI). Qualitative and quantitative XRD analyses revealed that calcite was the dominant mineral followed by quartz which occurred as the lesser phase. The percentages of calcite and quartz in the sample were99.23 wt% and 0.77 wt% respectively. SEM/EDS analysis depicted the major elemental composition of thedeposit and then the SEM-micrograph demonstrated the spherical calcite dust as dominant phase. The composition of the limestone deposit compared favorably with standard except for high concentration of iron oxide (0.35 wt%) which is objectionable but the concentration of iron oxide is still tolerable for making green container glass (0.96 wt%). Notwithstanding, low grade Kalambaina limestone can be upgraded through beneficiation to minimize the iron oxide concentration. [ABSTRACT FROM AUTHOR]

The published data on sulfate-containing glass in silicate, borate, and phosphate systems are reviewed. The experimental data confirm the presence of [SO] groups in an isolated state in all systems, but the possible amount of SO in the glass composition is considerably higher in borate and phosphate systems. [ABSTRACT FROM AUTHOR]

Qasr al rabbah is an exceptional site that lies on the main Trajan road (the royal road) which passing between Debaan and Karak, also provides unique evidence of the characteristics that illustrate its importance in ancient time. X-ray fluorescence (XRF) on Roman glass was chosen as a reliable technique to obtain and identify the raw materials, including the type of modifiers that were used as well as the colorants and opacifiers used in Roman glass objects. Forteen glass samples have been analyzed using XRF technique and statistical analysis both descriptive and multivariate. The study revealed two groups of glass in the same region. The obtained results indicated the use of Natron as fluxing agent with alkali contents as well as using the soda ash too as a second type. Two compositional groups have been identified in this study, potash soda lime silicate K2O (Na2O)-CaOSiO2 (K2O/Na2O>1), soda potash lime silicate Na2O (K2O)-CaO-SiO2 (K2O/Na2O<1) and potash silicate K2O-SiO2 glass systems, respectively. According to the visual inspection of the assemblage different corrosion effects are noted. A few glass fragments show a significantly higher degree of corrosion. It is the only sample in which a silver iridescent and a browning layer have been formed. Biocorrosion also appear as an additional weathering factor. Moreover, the inner surfaces of the walls of some colorless sherds demonstrate high polymerization, which is not noted on the outside surfaces of the same samples. The glass samples slightly tinted in yellow-green by the natural sand impurities, was evidently and heavily corroded and gave indeed Na concentrations well below what was expected from the known historical glassmaking. [ABSTRACT FROM AUTHOR]

A total of 1496 investigated colourless glass analyses have been collected with the aim of achieving a clear geographical, typological, chronological and compositional overview on this particular type of glass. Based on manganese and antimony contents, four main groups were characterised: naturally colourless, Mn-decoloured, Sb-decoloured and Mn/Sb-decoloured. Main achievements relates to the chronological distribution of manganese and antimony technologies, the former being associated to a long lasting technology which culminated during the Late Antique period while the latter being practically absent after the 8 century AD, being at its acme during the Roman imperial period. Except for naturally colourless glass, glass-making technology mostly implied the use of impure sands and natron, relegating the other components to a virtually irrelevant presence, except during the Late Antique and Medieval periods. [ABSTRACT FROM AUTHOR]

The quality of the glass melt is determined by thermal and compositional homogeneity across the feeding channel. Achieving that homogeneity with stirrers made from precious metals as well as from refractory is a widespread method used in the glass industry. Homogenization of glass melts by stirring happens under laminar flow conditions due to the low Reynolds-numbers at typical stirring temperatures and viscosities. As the glass viscosity conditions do not permit turbulence, good homogenization is hard to achieve. Compositional and thermal differences such as cords cannot be fully dispersed, they can only be stretched and folded until they are virtually invisible. This poses the question: What stirrer geometry is fluiddynamically efficient as well as considering a multitude of other requirements such as low precious metal weight, longevity and robustness. In a project carried out by Umicore Platinum Engineered Materials, the flow inside a stirring cell was studied by computational fluid dynamics and predominantly by physical simulation in order to develop an advanced stirring device. Cord was simulated by colored tracer liquid at different locations in a glucose model and different stirring concepts were tested and compared. The exercise revealed valuable insight into how the glass flow should be affected and what geometry an efficient stirrer should have when it can be made from oxide dispersion strengthened PtRh-alloy. Finally, the study led to the development of the ARCtwister, a modular, self-supporting stirrer made from fine grain stabilized FKS®PtRh-alloy. The stirrer creates a unique S-curved flow characteristic moving the glass volume vertically. It also transports the glass horizontally from the outside to the bowl center and vice-versa. This concept provides very efficient homogenization, even at low speeds. Its combination of stiff stirring members, tubes, arcuated blades and helices creates an extremely rigid framework allowing for thin precious metal wall thicknesses. [ABSTRACT FROM AUTHOR]

A radiotracer investigation was carried out in a glass production unit in a glass industry. Lanthanum-140 as lanthanium oxide mixed with silica was used as a radiotracer to trace the molten glass in various sections of the unit. Residence time distributions of molten glass were measured and analyzed to identify the flow abnormities. The flow parameters such as breakthrough time, mean residence time, homogenization time, dead volume and flow patterns in different sections of the unit were obtained from the measured RTD data. The results of the investigation were used to improve and optimize the operation of the glass production unit. [ABSTRACT FROM AUTHOR]

Chinese ancient lead-barium glass has drawn lots of scholars’ attentions to its peculiar composition and mysterious technology. In the absence of exact historical documents about lead-barium glass-making, it is extremely difficult to study the origin and development of this kind of glass. In order to clarify the raw material adopted in glass-making process, a series of simulation experiments was conducted to produce lead-barium glass under varying mineral conditions. According to the results of the experiments and comparative analysis of archaeological samples and natural mineral raw materials, such as barite and witherite, it is possible to come to the conclusion that ancient Chinese craftsmen could only use witherite as barium-containing material to make the lead-barium glass. Moreover, the existence of barium carbonate ore in China was the most fundamental internal factor of the origin of lead-barium glass from the viewpoint of mineral resources. A better understanding of raw material of this ancient glass and improved identification of the product of lead-barium glass in the Chinese ancient society will aid in the recovery and analysis of glass artifacts and further efforts to reconstruct this mysterious technology. [ABSTRACT FROM AUTHOR]

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We present a detailed description of the layered structure developing in the walls of Egyptian Late Bronze Age glass-making vessels, and in similar vessels successfully replicated in laboratory experiments. The analyses show that this layered discolouration and change in ceramic composition is due to the interaction of the glass batch with the vessel during firing. The formation of this visually striking and easy to recognise pattern is due to the chloride content of primary glass batches and does not occur in vessels used to re-melt existing glass. Thus, we argue that these discolourations can be used as a reliable and easy field guide to identify glassmaking waste among Late Bronze Age ceramic assemblages, hopefully increasing the currently very small number of identified LBA glassmaking workshops. [ABSTRACT FROM AUTHOR]

The article discuses the role of alumina-zirconia-silica (AZS) refractories in soda-lime glass and determines the major properties for fuse- cast AZS to ensure high quality glass manufacturing. Specifically, it examines the key role of internal structure of AZS blocks, chemistry-redox and microstructure in glass contact properties.

The applicability of laser ablation multi-collector inductively coupled plasma-mass spectrometry (LA-MC-ICP-MS) for the determination of the B isotopic composition in Roman glasses was investigated. The δ 11 B values thus obtained provide information on the natron flux used during the glass-making process. The glass samples used for this purpose were previously characterized using pneumatic nebulization (PN) MC-ICP-MS. Unfortunately, this method is time-consuming and labor-intensive and consumes some 100 mg of sample, which is a rather high amount for ancient materials. Therefore, the use of the less invasive and faster LA-MC-ICP-MS approach was explored. In this work, the results for 29 Roman glasses and 4 home-made glasses obtained using both techniques were compared to assess the suitability of LA-MC-ICP-MS in this context. The results are in excellent agreement within experimental uncertainty. No difference in overall mass discrimination was observed between the Roman glasses, NIST SRM 610 reference glass and B6 obsidian. The expanded uncertainty of the LA-MC-ICP-MS approach was estimated to be < 2‰, which is similar to that obtained upon sample digestion and PN-MC-ICP-MS measurement. [ABSTRACT FROM AUTHOR]

The capability of producing multiple containers with different weights on the same machine line can give the glass plant more flexibility to organize production jobs, save cost on mold equipment, and reduce production loss due to job changes. To meet this need, Bucher Emhart glass has developed the multi gob weight control system, including multi weight feeder and the knowledge for how it can be applied. This paper presents the recent development of a model based setup algorithm for the Multi Gob Weight System. The algorithm makes the multi gob weight set up procedure quick, accurate, and easy for the end user. Plant trial results are included to validate the effectiveness of the setup algorithm implementation. [ABSTRACT FROM AUTHOR]

Dissolved gases in glass melts are known to influence properties of the melts as well as the resulting glass and dissolved water is thought to be one of the most influential of all the dissolved gases. In this work, the effect of vacuum processing and the ensuing changes in dissolved water concentration on various physical properties of soda-lime-silica glasses were studied. Glass melts with varying dissolved water concentration were prepared by melting frit at atmospheric and sub-atmospheric (»100 torr) pressures at 1450°C. The physical properties of these melts and the resulting glasses were determined by rotating spindle viscometry, beam bending viscometry, and spectroscopy. The densities of the glass samples were also determined. Results from these experiments are discussed in relation to prior work in the field and the implications of changes in properties on the glass making process are discussed. [ABSTRACT FROM AUTHOR]

This article focuses on identifying concrete behavior under high triaxial loading. The study is carried out within a more general context of understanding the behavior of concrete under impact. The effect of coarse aggregate shape and composition on concrete under high triaxial compression is examined by means of a very high-capacity triaxial press. The shape effect is further investigated using rolled aggregates, crushed aggregates and glass balls. The influence of aggregate composition is determined on concretes mixed with siliceous aggregates, glass aggregates and limestone aggregates. These analyses specifically indicate that coarse aggregate shape exerts no influence on the concrete response at high confinement. Moreover, concrete behaves like a non-cohesive granular stacking that seems to be governed by the compacted cement matrix provided a sufficiently high aggregate strength. Otherwise, a lower aggregate strength serves to weaken this granular stacking. At an intermediate level of confinement, the shear strength of concrete is mainly controlled by aggregates strength; however, irregularly-shaped coarse aggregates slightly increase the overall strength of concrete. [ABSTRACT FROM AUTHOR]

The recent developments of energy storage devices are concerned with larger energy storage ability, low loss and good temperature stability. It has a great technological importance in engineering science. The dielectric materials like ceramics and glass ceramics have great interest in electronic ceramic industry due to above concern. The ceramic dielectrics are used as a capacitive element in electronic circuits. The perovskite glass ceramics have very high dielectric constant and low dielectric loss. The high dielectric constant in glass ceramics is attributed to space charge polarization. In order to produce glass ceramics of high dielectric constant, barium titanate glass ceramics is the first discovered ferroelectric perovskite. In this review article, we are summarizing the dielectric behavior of perovskite glass ceramics such as BaTiO, SrTiO, PbTiO, (Ba,Sr)TiO and (Pb,Sr)TiO. [ABSTRACT FROM AUTHOR]

The article presents abstracts related to industrial archaeology which include benefits and challenges of conserving industrial buildings, increasing demand for farm gas engines and evidence for glass-making.

Requirements imposed on the quality of Dinas refractory (silica refractory) and mortar intended for the masonry of the roof of a high-capacity glassmaking furnace are formulated. A calculation of the parameters of a curved roof with width of the span 9 m using only wedge-shaped articles is presented. The efficiency requirements of the thermal insulation of the roof are determined. Anovel structure of thermal insulation based on the use of molded and unmolded articles is developed.With an average reheat temperature of the roof of 1486°C, the specific heat flow into the environment is 544 W/m, which is 33.4 - 57.6% below the indicators of well-known designs for the thermal insulation of the roof of a glassmaking furnace. [ABSTRACT FROM AUTHOR]

An analytical review of the literature on changes in glassmaking processes, diathermancy of molten glass and light transmission of glass as a function of the redox potential of the raw material and batch is given. Experimental data on the effect of the redox potentials (RP) of batches and cullet on the color of glasses with commercial compositions are presented. The conditions for transformations and equilibrium of iron oxides in glassmaking are examined. [ABSTRACT FROM AUTHOR]

The materials of glass vessels for making glass produced by different manufacturers are investigated. Conclusions concerning the reasons for fracturing of the vessels are drawn on the basis of data from dilatometric analysis as well as optical and electronic microscopy. [ABSTRACT FROM AUTHOR]

A novel three-cycle scheme is proposed for recovering heat from the flue gases in glassmaking furnaces. The theoretical principles validating the correctness of prescribing the main initial data for calculating a three-cycle regenerator are formulated. An example of the development of a three-cycle regenerator for a glassmaking furnace with a horseshoe flame configuration is presented. [ABSTRACT FROM AUTHOR]

The article discusses glass industry history in the eastern empire of Herodian Israel and its impact on the west Roman world. Topics include glass blowing technology influenced by tastes and preferences reducing the prices of glassware and making it available to the common man, production sites and shipping interconnection of raw materials leading to sophisticated system of marketing and manufacturing, and shift from Hellenistic glass casting techniques to kiln sagging methods.

The article discusses the artisanal glassmaking industry in Antwerp, Belgium during the early modern period, with particular focus on the determination of value of glass pieces. Other topics include the spread of the glass industry from Venice, Italy, the translations of various Italian technical works on glassmaking subjects such as recipes, alchemy, and chalcedony glass, and how these translations were used to build the glass industry and increase Antwerp's influence as a world cultural center.

Abstract: In this study, rice husk was used as a biomass raw material as a substitute for commercial silica in glass making. The mass fraction of silica in rice husk ash (RHA) derived from rice husk powder by combustion at 1000 °C for 2 h was found to be as high as 96%, comparable to that of commercial silica. To make the rice husk glass a more value-added product, the addition of green photoluminescent (PL) pigments into rice husk glass was attempted. Green PL pigment was found to withstand high temperatures while maintaining its photoluminescent properties. Experiments were performed to add the PL pigment using two different methods, namely layering and mixing techniques. For the layering technique, the PL rice husk glass was produced by spreading the PL pigment between two layers of casted rice husk glass, resulting in a sandwich-like structure. On the other hand, through the mixing technique, the PL pigment was mixed directly into the molten glass. PL rice husk glass produced using the layering technique yielded a more preferable product. Some PL pigments were decomposed at high temperature during the glass making process, causing the pigment to lose its PL properties. As a result, the layering technique, which involved a lower level of decomposition of the PL pigment, was preferred to produce a PL rice husk glass with better PL properties compared to the mixing technique, which exposed more PL pigment to high temperature attack. [Copyright &y& Elsevier]

The aim of this work is to examine whether it is possible to find chemical markers that allow a distinction to be made between the imported black glossed 'Campanian A' and the Sicilian imitation (end of fourth to first century bc) of these productions by carrying out quantitative chemical microanalysis of the slip using the SEM- EDS technique. The efficiency of the proposed analytical method has been tested on a set of ceramic samples corresponding to Sicilian black gloss imitations whose ceramic body has already been characterized petrographically by thin-section microscopy and chemically by XRF. The analytical data point to Na2O as a suitable chemical marker to distinguish between original 'Campanian A' imported from the Gulf of Naples area and Sicilian imitations of the same forms of Hellenistic pottery. In order to verify the above result, the enrichment factors ( EFs) between the raw clays, the corresponding ceramic body and black gloss slip were calculated. Some differences in the patterns of EFs between original 'Campanian A' and Sicilian imitations were recognized and explained. Therefore, the obtained results can help to accomplish a first distinction between imported and local material on a firm analytical basis, working on a statistically significant number of individuals. [ABSTRACT FROM AUTHOR]

Yellow and colorless ancient glasses, which were once used to decorate the Temple of the Emerald Buddha, Bangkok, Thailand, around 150 years ago, are studied to unravel the long-lost glass-making recipes and manufacturing techniques. Analyses of chemical compositions, using synchrotron x-ray fluorescence (SRXRF), indicate that the Thai ancient glasses are soda lime silica glasses (60 % SiO; 10 % NaO; 10 % CaO) bearing lead oxide between 2-16 %. Iron (1.5-9.4 % FeO) and manganese (1.7 % MnO) are present in larger abundance than the other 3 d transition metals detected (0.04-0.2 %). K-edge x-ray absorption near edge spectroscopy (XANES) and extended x-ray absorption fine structure spectroscopy (EXAFS) provide conclusive evidence on the oxidation states of Fe being 3+ and Mn being 2+ and on short-length tetrahedral structures around the cations. This suggests that iron is used as a yellow colorant with manganese as a decolorant. L-edge XANES results reveal the oxidation states of lead as 2+. The results from this work provide information crucial for replicating these decorative glasses for the future restoration of the Temple of the Emerald Buddha. [ABSTRACT FROM AUTHOR]

The provenancing of Roman natron glass is one of the most challenging problems in the field of archaeometry. Although the use of Sr and Nd isotope ratios and trace element signatures as an indication of provenance has proven promising, there are still many unknowns. In this study, the influence of the different raw materials on the final Sr isotopic composition of Roman natron glass is examined. It is shown that the 87Sr/86Sr ratio in natron glass is significantly influenced by the silicate fraction of the sand used and does not always provide a clear indication of the lime source used. [ABSTRACT FROM AUTHOR]

The process of making float-glass in large-tonnage glassmaking furnaces is analyzed. The optimal values of the rate and duration of melting and cooling of the molten glass are determined. It is shown that the melting time of the glass is 48 - 72 h and depends on the content of the cullet in the batch. The glass melt remains chemically and structurally uniform with cooling rates 10 - 12 K/h and cooling times 20 - 24 h, which yields glass of optimal quality. [ABSTRACT FROM AUTHOR]

This work describes the experimental results related to several series of circular cross-section concrete columns reinforced by composite materials glass/polyester. The columns have been wrapped externally with several plies, and subjected to classical static uniaxial compression loading, and a novel compressive technique consisting in repeated loading steps. The authors identify in particular two specific composite layups (bidirectional fabrics (0/90)2 and (+30/−60)2), the first providing the highest time to failure, the second showing an increase up to 70% in strengthening efficiency compared with non-reinforced columns. Six hybrid composite jacket configurations have also been investigated. The authors also provide a cost analysis of the different types of layups used to wrap the columns, showing the enhanced mechanical/cost effectiveness of the reinforcements proposed in this article. [ABSTRACT FROM AUTHOR]

Yüzey işlemleriyle malzemenin sertlik, süneklik ve yorulma gibi mekanik özellikleri yanında sürtünme ve aşınma, oksidasyon ve korozyona karşı dayanıklılık özellikleri geliştirilmektedir. Sürtünerek çalışan makina elemanlarında belirli bir süre sonra ortaya çıkan aşınma problemlerini azaltmak için birçok yüzey iyileştirme teknikleri uygulanmaktadır. Yaşanan malzeme ve ürün kayıplarını, cam şekillendirme makinalarında minimuma indirmek ve söz konusu bu nedenlerden kaynaklanan duruş ve üretim kayıplarını azaltmak amacı ile gerçekleştirilen bu çalışmada; cam üretim makinalarında kullanılan kalıp kollarının malzemelerine alternatif malzeme ve kaplama türleri denenmiştir. Cam şekillendirme makinalarında mevcut kalıp kolu malzemesi olan AISI 420 kalite çeliğe alternatif olarak seçilen yüzeyi kaplanmış (nitrokarbürleme, sert krom kaplama, akımsız nikel kaplama ve borlama) üç farklı kalitede çelik (AISI 1040, AISI 4140 ve AISI 5140 kalite çelikler) malzeme, kalıp kollarındaki gerçek aşınma şartlarını simule edebilecek şekilde tasarlanan laboratuvar deneyleri için standart numuneler olarak hazırlanmıştır. Hazırlanan numunelere, metal-metal deneyleri yapılarak aşınma davranışları incelenmiştir. Oda sıcaklığında yapılan deneylerde nem ve sıcaklık sabit tutulmuştur. Metal-metal aşınma deneylerinde, pimlere M2 kalite takım çeliği üzerinde aşınma testi uygulanmıştır. Farklı kalitede çelikten imal edilmiş olan kaplanmış taban malzemelerine uygulanan disk üstünde pim deneyi sonucunda kullanılmakta olan sert krom kaplı ve kaplamasız AISI 420 kalite çeliğin bor kaplı AISI 4140 kalite çelik malzemeye göre aşınma oranının sırasıyla yaklaşık 18.67 ve 184 kat daha çok olduğu tespit edilmiştir. Laboratuvar deneylerinin sonucunda AISI 4140 kalite çelik malzeme üzerine borlama ön plana çıkmış ve kalıp kollarının çalışma koşullarında aşınmaya en dayanıklı kaplama ve taban malzemesi olarak borlanmış AISI 4140 kalite çelik kabul edilmiştir. [ABSTRACT FROM AUTHOR]